This results in small increases in the size of the .debug_loc section
and the number of unique source variables in a stage2 build of opt.
llvm-svn: 325301
Summary:
The behavior described in Coroutines TS `[dcl.fct.def.coroutine]/7`
allows coroutine parameters to be passed into allocator functions.
The instructions to store values into the alloca'd parameters must not
be moved past the frame allocation, otherwise uninitialized values are
passed to the allocator.
Test Plan: `check-llvm`
Reviewers: rsmith, GorNishanov, eric_niebler
Reviewed By: GorNishanov
Subscribers: compnerd, EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D43000
llvm-svn: 325285
The variable name 'AllowReassociate' is a lie at this point because
it's set to 'isFast()' which is more than the 'reassoc' FMF after
rL317488.
In D41286, we showed that this transform may be valid even with strict
math by brute force checking every 32-bit float result.
There's a potential problem here because we're replacing with a tan()
libcall rather than a hypothetical LLVM tan intrinsic. So we might
set errno when we should be guaranteed not to do that. But that's
independent of this change.
llvm-svn: 325247
Move computeLoopSafetyInfo, defined in Transforms/Utils/LoopUtils.h,
into the corresponding LoopUtils.cpp, as opposed to LICM where it resides
at the moment. This will allow other functions from Transforms/Utils
to reference it.
llvm-svn: 325151
The select may have been preventing a division by zero or INT_MIN/-1 so removing it might not be safe.
Fixes PR36362.
Differential Revision: https://reviews.llvm.org/D43276
llvm-svn: 325148
This keeps with our current usage of 'match' and is easier to see that
the optional NSW only applies in the non-constant operand case.
llvm-svn: 325140
Summary:
Reversed loads are handled as gathering. But we can just reshuffle
these values. Patch adds support for vectorization of reversed loads.
Reviewers: RKSimon, spatel, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43022
llvm-svn: 325134
For basic blocks with instructions between the beginning of the block
and a call we have to duplicate the instructions before the call in all
split blocks and add PHI nodes for uses of the duplicated instructions
after the call.
Currently, the threshold for the number of instructions before a call
is quite low, to keep the impact on binary size low.
Reviewers: junbuml, mcrosier, davidxl, davide
Reviewed By: junbuml
Differential Revision: https://reviews.llvm.org/D41860
llvm-svn: 325126
We can use incremental dominator tree updates to avoid re-calculating
the dominator tree after interchanging 2 loops.
Reviewers: dmgreen, kuhar
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D43176
llvm-svn: 325122
Preserve debug info from a dead 'and' instruction with a constant.
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D43163
llvm-svn: 325119
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.
Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html
I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.
Differential Revision: https://reviews.llvm.org/D42123
llvm-svn: 325102
This preserves an additional 581 unique source variables in a stage2
build of clang (according to `llvm-dwarfdump --statistics`). It
increases the size of the .debug_loc section by 0.1% (or 87139 bytes).
Differential Revision: https://reviews.llvm.org/D43255
llvm-svn: 325063
This replaces the bit-tracking based fold that did the same thing,
but it only worked for scalars and not directly.
There is no evidence in existing regression tests that the greater
power of bit-tracking was needed here, but we should be aware of
this potential loss of optimization.
llvm-svn: 325062
This is both a functional improvement for vectors and an
efficiency improvement for scalars. The existing code below
the new folds does the same thing for scalars, but in an
indirect and expensive way.
llvm-svn: 325048
According to `llvm-dwarfdump --statistics` this salvages 43 additional
unique source variables in a stage2 build of clang. It increases the
size of the .debug_loc section by 0.002% (or 2864 bytes).
Differential Revision: https://reviews.llvm.org/D43220
llvm-svn: 325035
For basic blocks with instructions between the beginning of the block
and a call we have to duplicate the instructions before the call in all
split blocks and add PHI nodes for uses of the duplicated instructions
after the call.
Currently, the threshold for the number of instructions before a call
is quite low, to keep the impact on binary size low.
Reviewers: junbuml, mcrosier, davidxl, davide
Reviewed By: junbuml
Differential Revision: https://reviews.llvm.org/D41860
llvm-svn: 325001
In cases where the OuterMostLoopLatchBI only has a single successor,
accessing the second successor will fail.
This fixes a failure when building the test-suite with loop-interchange
enabled.
Reviewers: mcrosier, karthikthecool, davide
Reviewed by: karthikthecool
Differential Revision: https://reviews.llvm.org/D42906
llvm-svn: 324994
We already try to salvage debug values from no-op bitcasts and inttoptr
instructions: we should handle ptrtoint instructions as well.
This saves an additional 24,444 debug values in a stage2 build of clang,
and (according to llvm-dwarfdump --statistics) provides an additional
289 unique source variables.
llvm-svn: 324982
Here are the number of additional debug values salvaged in a stage2
build of clang:
63 SALVAGE: MUL
1250 SALVAGE: SDIV
(No values were salvaged from `srem` instructions in this experiment,
but it's a simple case to handle so we might as well.)
llvm-svn: 324976
Here are the number of additional debug values salvaged in a stage2
build of clang:
1912 SALVAGE: ASHR
405 SALVAGE: LSHR
249 SALVAGE: SHL
llvm-svn: 324975
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
InstCombine pass to cease using the deprecated MemoryIntrinsic::getAlignment() method, and
instead we use the separate getSourceAlignment and getDestAlignment APIs to simplify
the source and destination alignment attributes separately.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
Reviewers: majnemer, bollu, efriedma
Reviewed By: efriedma
Subscribers: efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D42871
llvm-svn: 324960
It caused assertion failure
Assertion failed: (!DD.IsLambda && !MergeDD.IsLambda && "faked up lambda definition?"), function MergeDefinitionData, file /Users/buildslave/jenkins/workspace/clang-stage1-configure-RA/llvm/tools/clang/lib/Serialization/ASTReaderDecl.cpp, line 1675.
on the second stage build bots.
llvm-svn: 324932
This is similar to the instsimplify fold added with D42385
( rL323716 )
...but this can't be in instsimplify because we're creating/morphing
a different instruction.
llvm-svn: 324927
Update BlockColors after splitting predecessors. Do not allow splitting
EHPad for sinking when the BlockColors is not empty, so we can
simply assign predecessor's color to the new block.
Fixes PR36184
llvm-svn: 324916
Summary:
For better vectorization result we should take into consideration the
cost of the user insertelement instructions when we try to
vectorize sequences that build the whole vector. I.e. if we have the
following scalar code:
```
<Scalar code>
insertelement <ScalarCode>, ...
```
we should consider the cost of the last `insertelement ` instructions as
the cost of the scalar code.
Reviewers: RKSimon, spatel, hfinkel, mkuper
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D42657
llvm-svn: 324893
Add GraphTraits definitions to the FunctionSummary and ModuleSummaryIndex classes. These GraphTraits will be used to construct find SCC's in ThinLTO analysis passes.
llvm-svn: 324854
The related cases for (X * Y) / X were handled in rL124487.
https://rise4fun.com/Alive/6k9
The division in these tests is subsequently eliminated by existing instcombines
for 1/X.
llvm-svn: 324843
Summary:
If -pass-remarks=loop-vectorize, atomic ops will be seen by
analyzeInterleaving(), even though canVectorizeMemory() == false. This
is because we are requesting extra analysis instead of bailing out.
In such a case, we end up with a Group in both Load- and StoreGroups,
and then we'll try to access freed memory when traversing LoadGroups after having had released the Group when iterating over StoreGroups.
The fix is to include mayWriteToMemory() when validating that two
instructions are the same kind of memory operation.
Reviewers: mssimpso, davidxl
Reviewed By: davidxl
Subscribers: hsaito, fhahn, llvm-commits
Differential Revision: https://reviews.llvm.org/D43064
llvm-svn: 324786
Extend salvageDebugInfo to preserve the debug info from a dead 'or'
with a constant.
Patch by Ismail Badawi!
Differential Revision: https://reviews.llvm.org/D43129
llvm-svn: 324764
Summary:
For symbols that has linkonce_odr linkage and unnamed_addr, it can be
auto hide by linker to avoid weak external symbols. Teach ThinLTO to
perform auto hide so it can safely promote linkonce_odr to weak symbols
without breaking this nice property.
Reviewers: tejohnson, mehdi_amini
Reviewed By: tejohnson
Subscribers: inglorion, eraman, rnk, pcc, llvm-commits
Differential Revision: https://reviews.llvm.org/D43130
llvm-svn: 324757
Summary:
Kernel addresses have 0xFF in the most significant byte.
A tag can not be pushed there with OR (tag << 56);
use AND ((tag << 56) | 0x00FF..FF) instead.
Reviewers: kcc, andreyknvl
Subscribers: srhines, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D42941
llvm-svn: 324691
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
DataFlowSanitizer pass to cease using the old get/setAlignment() API of MemoryIntrinsic
in favour of getting source & dest specific alignments through the new API.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324654
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
AddressSanitizer pass to cease using The old IRBuilder CreateMemCpy single-alignment API
in favour of the new API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324653
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
MemorySanitizer pass to cease using the old IRBuilder CreateMemCpy single-alignment APIs
in favour of the new API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324642
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
LoopIdiom pass to cease using the old IRBuilder CreateMemCpy single-alignment APIs in
favour of the new API that allows setting source and destination alignments independently.
This allows us to be slightly more aggressive in setting the alignment of memcpy calls that
loop idiom creates.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324626
Refactor getLogBase2Vector into getLogBase2 to accept all scalars/vectors. Generalize from ConstantDataVector to support all constant vectors.
llvm-svn: 324603
Summary:
GVN hoist pass is using PostDominatorTree analysis, therefore the analysis
should be listed in the pass initialization as a dependency.
Reviewed By: sebpop
Differential Revision: https://reviews.llvm.org/D43007
Author: ashlykov <arkady.shlykov@intel.com>
llvm-svn: 324597
Add support of uge and sge latch condition to Loop Prediction for
reverse loops.
Reviewers: apilipenko, mkazantsev, sanjoy, anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42837
llvm-svn: 324589
With fix: reimplemented.
Original commit message:
Recently introduced convertToDeclaration is very similar
to code used in filterModule function.
Patch reuses it to reduce duplication.
Differential revision: https://reviews.llvm.org/D42971
llvm-svn: 324574
The commit rL308422 introduces a restriction for folding unconditional
branches. Specifically if empty block with unconditional branch leads to
header of the loop then elimination of this basic block is prohibited.
However it seems this condition is redundantly strict.
If elimination of this basic block does not introduce more back edges
then we can eliminate this block.
The patch implements this relax of restriction.
The test profile/Linux/counter_promo_nest.c in compiler-rt project
is updated to meet this change.
Reviewers: efriedma, mcrosier, pacxx, hsung, davidxl
Reviewed By: pacxx
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42691
llvm-svn: 324572
Summary:
Loops with inequality comparers, such as:
// unsigned bound
for (unsigned i = 1; i < bound; ++i) {...}
have getSmallConstantMaxTripCount report a large maximum static
trip count - in this case, 0xffff fffe. However, profiling info
may show that the trip count is much smaller, and thus
counter-recommend vectorization.
This change:
- flips loop-vectorize-with-block-frequency on by default.
- validates profiled loop frequency data supports vectorization,
when static info appears to not counter-recommend it. Absence
of profile data means we rely on static data, just as we've
done so far.
Reviewers: twoh, mkuper, davidxl, tejohnson, Ayal
Reviewed By: davidxl
Subscribers: bkramer, llvm-commits
Differential Revision: https://reviews.llvm.org/D42946
llvm-svn: 324543
Recently introduced convertToDeclaration is very similar
to code used in filterModule function.
Patch reuses it to reduce duplication.
Differential revision: https://reviews.llvm.org/D42971
llvm-svn: 324455
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
DeadStoreElimination pass to cease using the old getAlignment() API of MemoryIntrinsic
in favour of getting dest specific alignments through the new API.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324402
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
InferAddressSpaces pass to cease using:
1) The old getAlignment() API of MemoryIntrinsic in favour of getting source & dest specific
alignments through the new API.
2) The old IRBuilder CreateMemCpy/CreateMemMove single-alignment APIs in favour of the new
API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324395
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
InlineFunction pass to ceause using the old IRBuilder CreateMemCpy single-alignment API
in favour of the new API that allows setting source and destination alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324384
- Fix condition for detecting that a complex basic block was the first in
the chain.
- Add tests.
This was caught by buildbots when submitting rL324319.
llvm-svn: 324341
It is better to update pointer of the DISuprogram before we call RAUW for
still live arguments of the function, because with the change reviewed in
D42541 in RAUW we compare DISubprograms rather than functions itself.
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D42794
llvm-svn: 324335
If the inline asm provides the definition of a symbol, this can result
in duplicate symbol errors.
Differential Revision: https://reviews.llvm.org/D42944
llvm-svn: 324313
In the motivating case from PR35681 and represented by the macro-fuse-cmp test:
https://bugs.llvm.org/show_bug.cgi?id=35681
...there's a 37 -> 31 byte size win for the loop because we eliminate the big base
address offsets.
SPEC2017 on Ryzen shows no significant perf difference.
Differential Revision: https://reviews.llvm.org/D42607
llvm-svn: 324289
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
LowerMemIntrinsics pass to cease using the old getAlignment() API of MemoryIntrinsic in
favour of getting source & dest specific alignments through the new API.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324278
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
SimplifyLibCalls pass to cease using the old IRBuilder createMemCpy/createMemMove
single-alignment APIs in favour of the new API that allows setting source and destination
alignments independently.
Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, r3L24148 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.
Reference
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
llvm-svn: 324273
This is the instcombine part of unsigned saturation canonicalization.
Backend patches already commited:
https://reviews.llvm.org/D37510https://reviews.llvm.org/D37534
It converts unsigned saturated subtraction patterns to forms recognized
by the backend:
(a > b) ? a - b : 0 -> ((a > b) ? a : b) - b)
(b < a) ? a - b : 0 -> ((a > b) ? a : b) - b)
(b > a) ? 0 : a - b -> ((a > b) ? a : b) - b)
(a < b) ? 0 : a - b -> ((a > b) ? a : b) - b)
((a > b) ? b - a : 0) -> - ((a > b) ? a : b) - b)
((b < a) ? b - a : 0) -> - ((a > b) ? a : b) - b)
((b > a) ? 0 : b - a) -> - ((a > b) ? a : b) - b)
((a < b) ? 0 : b - a) -> - ((a > b) ? a : b) - b)
Patch by Yulia Koval!
Differential Revision: https://reviews.llvm.org/D41480
llvm-svn: 324255
There was a logic hole in D42739 / rL324014 because we're not accounting for select and phi
instructions that might have repeated operands. This is likely a source of an infinite loop.
I haven't manufactured a test case to prove that, but it should be safe to speculatively limit
this transform to binops while we try to create that test.
llvm-svn: 324252
This broke the Chromium build; see PR36238.
> This patch is an enhancement to propagate dbg.value information when
> Phis are created on behalf of LCSSA. I noticed a case where a value
> carried across a loop was reported as <optimized out>.
>
> Specifically this case:
>
> int bar(int x, int y) {
> return x + y;
> }
>
> int foo(int size) {
> int val = 0;
> for (int i = 0; i < size; ++i) {
> val = bar(val, i); // Both val and i are correct
> }
> return val; // <optimized out>
> }
>
> In the above case, after all of the interesting computation completes
> our value is reported as "optimized out." This change will add a
> dbg.value to correct this.
>
> This patch also moves the dbg.value insertion routine from
> LoopRotation.cpp into Local.cpp, so that we can share it in both places
> (LoopRotation and LCSSA).
>
> Patch by Matt Davis!
>
> Differential Revision: https://reviews.llvm.org/D42551
llvm-svn: 324247
Summary:
This complements the fixes in r323633 and r324075 which drop the
definitions of dead functions and variables, respectively.
Fixes PR36208.
Reviewers: grimar, rafael
Subscribers: mehdi_amini, llvm-commits, inglorion
Differential Revision: https://reviews.llvm.org/D42856
llvm-svn: 324242
The patch causes the failure of the test
compiler-rt/test/profile/Linux/counter_promo_nest.c
To unblock buildbot, revert the patch while investigation is in progress.
Differential Revision: https://reviews.llvm.org/D42691
llvm-svn: 324214
The commit rL308422 introduces a restriction for folding unconditional
branches. Specifically if empty block with unconditional branch leads to
header of the loop then elimination of this basic block is prohibited.
However it seems this condition is redundantly strict.
If elimination of this basic block does not introduce more back edges
then we can eliminate this block.
The patch implements this relax of restriction.
Reviewers: efriedma, mcrosier, pacxx, hsung, davidxl
Reviewed By: pacxx
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42691
llvm-svn: 324208
ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check
that SCEV is available at entry point of the loop. It is incorrect and fixed by patch.
To bugs additionally fixed:
assert is moved after the check whether loop is not a nullptr.
Usage of isLoopEntryGuardedByCond in ScalarEvolution::isImpliedCondOperandsViaNoOverflow
is guarded by isAvailableAtLoopEntry.
Reviewers: sanjoy, mkazantsev, anna, dorit, reames
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42417
llvm-svn: 324204
When using the partial inliner, we might have attributes for forwarded
varargs, but the CodeExtractor does not create an empty argument
attribute set for regular arguments in that case, because it does not know
of the additional arguments. So in case we have attributes for VarArgs, we
also have to make sure we create (empty) attributes for all regular arguments.
This fixes PR36210.
llvm-svn: 324197
The type-shrinking logic in reduction detection, although narrow in scope, is
also rather ad-hoc, which has led to bugs (e.g., PR35734). This patch modifies
the approach to rely on the demanded bits and value tracking analyses, if
available. We currently perform type-shrinking separately for reductions and
other instructions in the loop. Long-term, we should probably think about
computing minimal bit widths in a more complete way for the loops we want to
vectorize.
PR35734
Differential Revision: https://reviews.llvm.org/D42309
llvm-svn: 324195
This, in instcombine, allows conversions to i8/i16/i32 (very
common cases) even if the resulting type is not legal according
to the data layout. This can often open up extra combine
opportunities.
Differential Revision: https://reviews.llvm.org/D42424
llvm-svn: 324174
Summary:
When creating the debug fragments for a SRA'd variable, use the types'
allocation sizes. This fixes issues where the pass would emit too small
fragments, placed at the wrong offset, for padded types.
An example of this is long double on x86. The type is represented using
x86_fp80, which is 10 bytes, but the value is aligned to 12/16 bytes.
The padding is included in the type's DW_AT_byte_size attribute;
therefore, the fragments should also include that. Newer GCC releases
(I tested 7.2.0) emit 12/16-byte pieces for long double. Earlier
releases, e.g. GCC 5.5.0, behaved as LLVM did, i.e. by emitting a
10-byte piece, followed by an empty 2/6-byte piece for the padding.
Failing to cover all `DW_AT_byte_size' bytes of a value with non-empty
pieces results in the value being printed as <optimized out> by GDB.
Patch by: David Stenberg
Reviewers: aprantl, JDevlieghere
Reviewed By: aprantl, JDevlieghere
Subscribers: llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D42807
llvm-svn: 324066
This is the enhancement suggested in D42536 to fix a shortcoming in
regular InstCombine's canEvaluate* functionality.
When we have multiple uses of a value, but they're all in one instruction, we can
allow that expression to be narrowed or widened for the same cost as a single-use
value.
AFAICT, this can only matter for multiply: sub/and/or/xor/select would be simplified
away if the operands are the same value; add becomes shl; shifts with a variable shift
amount aren't handled.
Differential Revision: https://reviews.llvm.org/D42739
llvm-svn: 324014
This, in instcombine, allows conversions to i8/i16/i32 (very
common cases) even if the resulting type is not legal according
to the data layout. This can often open up extra combine
opportunities.
Differential Revision: https://reviews.llvm.org/D42424
llvm-svn: 323951
Summary:
Before emitting code for scaled registers, we prevent
SCEVExpander from hoisting any scaled addressing mode
by emitting all the bases first. However, these bases
are being forced to the final type, resulting in some
odd code.
For example, if the type of the base is an integer and
the final type is a pointer, we will emit an inttoptr
for the base, a ptrtoint for the scale, and then a
'reverse' GEP where the GEP pointer is actually the base
integer and the index is the pointer. It's more intuitive
to use the pointer as a pointer and the integer as index.
Patch by: Bevin Hansson
Reviewers: atrick, qcolombet, sanjoy
Reviewed By: qcolombet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42103
llvm-svn: 323946
For very, very large global initializers which can be statically evaluated, the
code would create vectors of temporary Constants, modifying them in place,
before committing the resulting Constant aggregate to the global's initializer
value. This had effectively O(n^2) complexity in the size of the global
initializer and would cause memory and non-termination issues compiling some
workloads.
This change performs the static initializer evaluation and creation in batches,
once for each global in the evaluated IR memory. The existing code is maintained
as a last resort when the initializers are more complex than simple values in a
large aggregate. This should theoretically by NFC, no test as the example case
is massive. The existing test cases pass with this, as well as the llvm test
suite.
To give an example, consider the following C++ code adapted from the clang
regression tests:
struct S {
int n = 10;
int m = 2 * n;
S(int a) : n(a) {}
};
template<typename T>
struct U {
T *r = &q;
T q = 42;
U *p = this;
};
U<S> e;
The global static constructor for 'e' will need to initialize 'r' and 'p' of
the outer struct, while also initializing the inner 'q' structs 'n' and 'm'
members. This batch algorithm will simply use general CommitValueTo() method
to handle the complex nested S struct initialization of 'q', before
processing the outermost members in a single batch. Using CommitValueTo() to
handle member in the outer struct is inefficient when the struct/array is
very large as we end up creating and destroy constant arrays for each
initialization.
For the above case, we expect the following IR to be generated:
%struct.U = type { %struct.S*, %struct.S, %struct.U* }
%struct.S = type { i32, i32 }
@e = global %struct.U { %struct.S* gep inbounds (%struct.U, %struct.U* @e,
i64 0, i32 1),
%struct.S { i32 42, i32 84 }, %struct.U* @e }
The %struct.S { i32 42, i32 84 } inner initializer is treated as a complex
constant expression, while the other two elements of @e are "simple".
Differential Revision: https://reviews.llvm.org/D42612
llvm-svn: 323933
This covers the case where TruncInst leaf node is a constant expression.
See PR36121 for more details.
Differential Revision: https://reviews.llvm.org/D42622
llvm-svn: 323926
If you have a long chain of select instructions created from something
like `int* p = &g; if (foo()) p += 4; if (foo2()) p += 4;` etc., a naive
recursive visitor will recursively visit each select twice, which is
O(2^N) in the number of select instructions. Use the visited set to cut
off recursion in this case.
(No testcase because this doesn't actually change the behavior, just the
time.)
Differential Revision: https://reviews.llvm.org/D42451
llvm-svn: 323910
Because dead code may contain non-standard IR that causes infinite looping or crashes in underlying analysis.
See PR36134 for more details.
Differential Revision: https://reviews.llvm.org/D42683
llvm-svn: 323862
Summary:
This is exposed during ThinLTO compilation, when we import an alias by
creating a clone of the aliasee. Without this fix the debug type is
unnecessarily cloned and we get a duplicate, undoing the uniquing.
Fixes PR36089.
Reviewers: mehdi_amini, pcc
Subscribers: eraman, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D41669
llvm-svn: 323813
candidates with coldcc attribute.
This recommits r322721 reverted due to sanitizer memory leak build bot failures.
Original commit message:
This patch adds support for the coldcc calling convention for Power.
This changes the set of non-volatile registers. It includes a pass to stress
test the implementation by marking all static directly called functions with
the coldcc attribute through the option -enable-coldcc-stress-test. It also
includes an option, -ppc-enable-coldcc, to add the coldcc attribute to
functions which are cold at all call sites based on BlockFrequencyInfo when
the containing function does not call any non cold functions.
Differential Revision: https://reviews.llvm.org/D38413
llvm-svn: 323778
Summary:
There's an asymmetry in the definitions of findBaseDefiningValueOfVector() and
findBaseDefiningValue() of RS4GC. The later handles call and invoke instructions,
and the former does not. This appears to be simple oversight. This patch remedies
the oversight by adding the call and invoke cases to findBaseDefiningValueOfVector().
Reviewers: DaniilSuchkov, anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42653
llvm-svn: 323764
Summary:
The JumpThreading pass has several locations where to the variable name LI
refers to a LoadInst type. This is confusing and inhibits the ability to use
LI for LoopInfo as a member of the JumpThreading class. Minor formatting
and comments were also altered to reflect this change.
Reviewers: dberlin, kuba, spop, sebpop
Reviewed by: sebpop
Subscribers: sebpop, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D42601
llvm-svn: 323695
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323662
This pretty much reverts r322006, except that we keep the test,
because we work around the issue exposed in a different way (a
recursion limit in value tracking). There's still probably some
sequence that exposes this problem, and the proper way to fix that
for somebody who has time is outlined in the code review.
llvm-svn: 323630
A cast from A to B is eliminable if its result is casted to C, and if
the pair of casts could just be expressed as a single cast. E.g here,
%c1 is eliminable:
%c1 = zext i16 %A to i32
%c2 = sext i32 %c1 to i64
InstCombine optimizes away eliminable casts. This patch teaches it to
insert a dbg.value intrinsic pointing to the final result, so that local
variables pointing to the eliminable result are preserved.
Differential Revision: https://reviews.llvm.org/D42566
llvm-svn: 323570
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323530
- using qualified pointer addrspace in intrinsics class to avoid .f32 mangling
- changed too common atomic mangling to ds
- added missing intrinsics to AMDGPUTTIImpl::getTgtMemIntrinsic
Reviewed by: b-sumner
Differential Revision: https://reviews.llvm.org/D42383
llvm-svn: 323516
Inserting a dbg.value instruction at the start of a basic block with a
landingpad instruction triggers a verifier failure. We should be OK if
we insert the instruction a bit later.
Speculative fix for the bot failure described here:
https://reviews.llvm.org/D42551
llvm-svn: 323482
Summary:
The intent of this is to allow the code to be used with ThinLTO. In
Thinlink phase, a traditional Callgraph can not be computed even though
all the necessary information (nodes and edges of a call graph) is
available. This is due to the fact that CallGraph class is closely tied
to the IR. This patch first extends GraphTraits to add a CallGraphTraits
graph. This is then used to implement a version of counts propagation
on a generic callgraph.
Reviewers: davidxl
Subscribers: mehdi_amini, tejohnson, llvm-commits
Differential Revision: https://reviews.llvm.org/D42311
llvm-svn: 323475
This patch is an enhancement to propagate dbg.value information when
Phis are created on behalf of LCSSA. I noticed a case where a value
carried across a loop was reported as <optimized out>.
Specifically this case:
int bar(int x, int y) {
return x + y;
}
int foo(int size) {
int val = 0;
for (int i = 0; i < size; ++i) {
val = bar(val, i); // Both val and i are correct
}
return val; // <optimized out>
}
In the above case, after all of the interesting computation completes
our value is reported as "optimized out." This change will add a
dbg.value to correct this.
This patch also moves the dbg.value insertion routine from
LoopRotation.cpp into Local.cpp, so that we can share it in both places
(LoopRotation and LCSSA).
Patch by Matt Davis!
Differential Revision: https://reviews.llvm.org/D42551
llvm-svn: 323472
Right now clang uses "_n" suffix for some user space callbacks and "N" for the matching kernel ones. There's no need for this and it actually breaks kernel build with inline instrumentation. Use the same callback names for user space and the kernel (and also make them consistent with the names GCC uses).
Patch by Andrey Konovalov.
Differential Revision: https://reviews.llvm.org/D42423
llvm-svn: 323470
It was reverted after buildbot regressions.
Original commit message:
This allows relative block frequency of call edges to be passed
to the thinlink stage where it will be used to compute synthetic
entry counts of functions.
llvm-svn: 323460
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323441
This is guarded by shouldChangeType(), so the tests show that
we don't do the fold if the narrower type is not legal. Note
that there is a proposal (D42424) that would change the results
for the specific cases shown in these tests. That difference is
also discussed in PR35792:
https://bugs.llvm.org/show_bug.cgi?id=35792
Alive proofs for the cases handled here as well as the bitwise
logic binops that we should already do better on:
https://rise4fun.com/Alive/c97https://rise4fun.com/Alive/Lc5Ehttps://rise4fun.com/Alive/kdf
llvm-svn: 323437
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323430
Summary:
When creating the debug fragments for a SRA'd struct, use the fields'
offsets, taken from the struct layout, as the offsets for the resulting
fragments. This fixes an issue where GlobalOpt would emit fragments with
incorrect offsets for padded fields.
This should solve PR36016.
Patch by David Stenberg.
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42489
llvm-svn: 323411
It causes regressions in various OpenGL test suites.
Keep the test cases introduced by r321751 as XFAIL, and add a test case
for the regression.
Change-Id: I90b4cc354f68cebe5fcef1f2422dc8fe1c6d3514
Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=36015
llvm-svn: 323355
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323348
Combine expression patterns to form expressions with fewer, simple instructions.
This pass does not modify the CFG.
For example, this pass reduce width of expressions post-dominated by TruncInst
into smaller width when applicable.
It differs from instcombine pass in that it contains pattern optimization that
requires higher complexity than the O(1), thus, it should run fewer times than
instcombine pass.
Differential Revision: https://reviews.llvm.org/D38313
llvm-svn: 323321
This patch removes assert that SCEV is able to prove that a value is
non-negative. In fact, SCEV can sometimes be unable to do this because
its cache does not update properly. This assert will be returned once this
problem is resolved.
llvm-svn: 323309
Summary:
Currently, there is no way to extract a basic block from a function easily. This patch
extends llvm-extract to extract the specified basic block(s).
Reviewers: loladiro, rafael, bogner
Reviewed By: bogner
Subscribers: hintonda, mgorny, qcolombet, llvm-commits
Differential Revision: https://reviews.llvm.org/D41638
llvm-svn: 323266
Summary:
If the same value is going to be vectorized several times in the same
tree entry, this entry is considered to be a gather entry and cost of
this gather is counter as cost of InsertElementInstrs for each gathered
value. But we can consider these elements as ShuffleInstr with
SK_PermuteSingle shuffle kind.
Reviewers: spatel, RKSimon, mkuper, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38697
llvm-svn: 323246
Summary:
This patch is adding remark messages to the LoopVersioning LICM pass,
which will be useful for optimization remark emitter (ORE) infrastructure.
Patch by: Deepak Porwal
Reviewers: anemet, ashutosh.nema, eastig
Subscribers: eastig, vivekvpandya, fhahn, llvm-commits
llvm-svn: 323183
Currently ASan instrumentation pass forces callback
instrumentation when applied to the kernel.
This patch changes the current behavior to allow
using inline instrumentation in this case.
Authored by andreyknvl. Reviewed in:
https://reviews.llvm.org/D42384
llvm-svn: 323140
ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check
that SCEV is available at entry point of the loop. It is incorrect and fixed by patch.
Reviewers: sanjoy, mkazantsev, anna, dorit
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42165
llvm-svn: 323077
...when the shift is known to not overflow with the matching
signed-ness of the division.
This closes an optimization gap caused by canonicalizing mul
by power-of-2 to shl as shown in PR35709:
https://bugs.llvm.org/show_bug.cgi?id=35709
Patch by Anton Bikineev!
Differential Revision: https://reviews.llvm.org/D42032
llvm-svn: 323068
We already had the pointer being stored to in the MemLoc, reuse that code. In merging cases, it turned out the interface of the getLocForWrite had become inconsitent with other related utilities. Fix that by making sure the input passes hasAnalyzableWrite as well.
llvm-svn: 323056
to @objc_autorelease if its operand is a PHI and the PHI has an
equivalent value that is used by a return instruction.
For example, ARC optimizer shouldn't replace the call in the following
example, as doing so breaks the AutoreleaseRV/RetainRV optimization:
%v1 = bitcast i32* %v0 to i8*
br label %bb3
bb2:
%v3 = bitcast i32* %v2 to i8*
br label %bb3
bb3:
%p = phi i8* [ %v1, %bb1 ], [ %v3, %bb2 ]
%retval = phi i32* [ %v0, %bb1 ], [ %v2, %bb2 ] ; equivalent to %p
%v4 = tail call i8* @objc_autoreleaseReturnValue(i8* %p)
ret i32* %retval
Also, make sure ObjCARCContract replaces @objc_autoreleaseReturnValue's
operand uses with its value so that the call gets tail-called.
rdar://problem/15894705
llvm-svn: 323009
Summary:
If the vectorized tree has truncate to minimum required bit width and
the vector type of the cast operation after the truncation is the same
as the vector type of the cast operands, count cost of the vector cast
operation as 0, because this cast will be later removed.
Also, if the vectorization tree root operations are integer cast operations, do not consider them as candidates for truncation. It will just create extra number of the same vector/scalar operations, which will be removed by instcombiner.
Reviewers: RKSimon, spatel, mkuper, hfinkel, mssimpso
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41948
llvm-svn: 322946
Three (or more) operand getelementptrs could plausibly also be handled, but
handling only two-operand fits in easily with the existing BinaryOperator
handling.
Differential Revision: https://reviews.llvm.org/D39958
llvm-svn: 322930
Summary:
-hwasan-mapping-offset defines the non-zero shadow base address.
-hwasan-kernel disables calls to __hwasan_init in module constructors.
Unlike ASan, -hwasan-kernel does not force callback instrumentation.
This is controlled separately with -hwasan-instrument-with-calls.
Reviewers: kcc
Subscribers: srhines, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D42141
llvm-svn: 322785
Summary:
The class wraps a uint64_t and an enum to represent the type of profile
count (real and synthetic) with some helper methods.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41883
llvm-svn: 322771
candidates with coldcc attribute.
This patch adds support for the coldcc calling convention for Power.
This changes the set of non-volatile registers. It includes a pass to stress
test the implementation by marking all static directly called functions with
the coldcc attribute through the option -enable-coldcc-stress-test. It also
includes an option, -ppc-enable-coldcc, to add the coldcc attribute to
functions which are cold at all call sites based on BlockFrequencyInfo when
the containing function does not call any non cold functions.
Differential Revision: https://reviews.llvm.org/D38413
llvm-svn: 322721
I was comparing the demanded-bits implementations between InstCombine
and TargetLowering as part of investigating questions in D42088 and
noticed that this was wrong in IR. We were losing all of the prior
known bits when we got back to the 'zext'.
llvm-svn: 322662
This removes some duplication from splitCallSite and makes it easier to
add additional code dealing with each predecessor. It also allows us to
split for more than 2 predecessors, although that is not enabled for
now.
Reviewers: junbuml, mcrosier, davidxl, davide
Reviewed By: junbuml
Differential Revision: https://reviews.llvm.org/D41858
llvm-svn: 322599
Summary: Sometimes vectorization of insertelement instructions with extractelement operands may produce an extra shuffle operation, if these operands are in the reverse order. Patch tries to improve this situation by the reordering of the operands to remove this extra shuffle operation.
Reviewers: mkuper, hfinkel, RKSimon, spatel
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D33954
llvm-svn: 322579
This patch fixes the assertion failure in SROA reported in PR35657.
PR35657 reports the assertion failure due to r319522 (splitting for non-whole-alloca slices), but this problem can happen even without r319522.
The problem exists in a check for reusing an existing alloca when rewriting partitions. As the original comment said, we can reuse the existing alloca if the new alloca has the same type and offset with the existing one. But the code checks only type of the alloca and then check the offset using an assert.
In a corner case with out-of-bounds access (e.g. @PR35657 function added in unit test), it is possible that the two allocas have the same type but different offsets.
This patch makes the check of the offset in the if condition, and re-enables the splitting for non-whole-alloca slices.
Differential Revision: https://reviews.llvm.org/D41981
llvm-svn: 322533
Summary:
This method is supposed to be called for IVs that have casts in their use-def
chains that are completely ignored after vectorization under PSE. However, for
truncates of such IVs the same InductionDescriptor is used during
creation/widening of both original IV based on PHINode and new IV based on
TruncInst.
This leads to unintended second call to recordVectorLoopValueForInductionCast
with a VectorLoopVal set to the newly created IV for a trunc and causes an
assert due to attempt to store new information for already existing entry in the
map. This is wrong and should not be done.
Fixes PR35773.
Reviewers: dorit, Ayal, mssimpso
Reviewed By: dorit
Subscribers: RKSimon, dim, dcaballe, hsaito, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D41913
llvm-svn: 322473
Summary:
In preparation for https://reviews.llvm.org/D41675 this NFC changes this
prototype of MemIntrinsicInst::setAlignment() to accept an unsigned instead
of a Constant.
llvm-svn: 322403
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 322401
Currently, IRC contains `Begin` and `Step` as SCEVs and `End` as value.
Aside from that, `End` can also be `nullptr` which can be later conditionally
converted into a non-null SCEV.
To make this logic more transparent, this patch makes `End` a SCEV and
calculates it early, so that it is never a null.
Differential Revision: https://reviews.llvm.org/D39590
llvm-svn: 322364
This is a fix for PR35884.
When we want to delete dead loop we must clean uses in unreachable blocks
otherwise we'll get an assert during deletion of instructions from the loop.
Reviewers: anna, davide
Reviewed By: anna
Subscribers: llvm-commits, lebedev.ri
Differential Revision: https://reviews.llvm.org/D41943
llvm-svn: 322357
Summary:
Very basic stack instrumentation using tagged pointers.
Tag for N'th alloca in a function is built as XOR of:
* base tag for the function, which is just some bits of SP (poor
man's random)
* small constant which is a function of N.
Allocas are aligned to 16 bytes. On every ReturnInst allocas are
re-tagged to catch use-after-return.
This implementation has a bunch of issues that will be taken care of
later:
1. lifetime intrinsics referring to tagged pointers are not
recognized in SDAG. This effectively disables stack coloring.
2. Generated code is quite inefficient. There is one extra
instruction at each memory access that adds the base tag to the
untagged alloca address. It would be better to keep tagged SP in a
callee-saved register and address allocas as an offset of that XOR
retag, but that needs better coordination between hwasan
instrumentation pass and prologue/epilogue insertion.
3. Lifetime instrinsics are ignored and use-after-scope is not
implemented. This would be harder to do than in ASan, because we
need to use a differently tagged pointer depending on which
lifetime.start / lifetime.end the current instruction is dominated
/ post-dominated.
Reviewers: kcc, alekseyshl
Subscribers: srhines, kubamracek, javed.absar, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D41602
llvm-svn: 322324
While updating clang tests for having clang set dso_local I noticed
that:
- There are *a lot* of tests to update.
- Many of the updates are redundant.
They are redundant because a GV is "obviously dso_local". This patch
starts formalizing that a bit by requiring that internal and private
GVs be dso_local too. Since they all are, we don't have to print
dso_local to the textual representation, making it a bit more compact
and easier to read.
llvm-svn: 322317
LoadInst isn't enough; we need to include intrinsics that perform loads too.
All side-effecting intrinsics and such are already covered by the isSafe
check, so we just need to care about things that read from memory.
D41960, originally from D33179.
llvm-svn: 322311
parent function
Ideally we should merge the attributes from the functions somehow, but
this is obviously an improvement over taking random attributes from the
caller which will trip up the verifier if they're nonsensical for an
unary intrinsic call.
llvm-svn: 322284
The function can take a significant amount of time on some
complicated test cases, but for the currently only use of
the function we can stop the initialization much earlier
when we find out we are going to discard the result anyway
in the caller of the function.
Adding configurable cut-off points so that we avoid wasting time.
NFCI.
llvm-svn: 322248
Summary:
LowerTypeTests moves some function definitions from individual object
files to the merged module, leaving a stub to be called in the merged
module's jump table. If an alias was pointing to such a function
definition LowerTypeTests would fail because the alias would be left
without a definition to point to.
This change 1) emits information about aliases to the ThinLTO summary,
2) replaces aliases pointing to function definitions that are moved to
the merged module with function declarations, and 3) re-emits those
aliases in the merged module pointing to the correct function
definitions.
The patch does not correctly fix all possible mis-uses of aliases in
LowerTypeTests. For example, it does not handle aliases with a different
type from the pointed to function.
The addition of alias data increases the size of Chrome build artifacts
by less than 1%.
Reviewers: pcc
Reviewed By: pcc
Subscribers: mehdi_amini, eraman, mgrang, llvm-commits, eugenis, kcc
Differential Revision: https://reviews.llvm.org/D41741
llvm-svn: 322139
Summary:
When performing constant propagation for call instructions we have historically replaced all uses of the return from a call, but not removed the call itself. This is required for correctness if the calls have side effects, however the compiler should be able to safely remove calls that don't have side effects.
This allows the compiler to completely fold away calls to functions that have no side effects if the inputs are constant and the output can be determined at compile time.
Reviewers: davide, sanjoy, bruno, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38856
llvm-svn: 322125
Summary:
This pass synthesizes function entry counts by traversing the callgraph
and using the relative block frequencies of the callsites. The intended
use of these counts is in inlining to determine hot/cold callsites in
the absence of profile information.
The pass is split into two files with the code that propagates the
counts in a callgraph in a Utils file. I plan to add support for
propagation in the thinlto link phase and the propagation code will be
shared and hence this split. I did not add support to the old PM since
hot callsite determination in inlining is not possible in old PM
(although we could use hot callee heuristic with synthetic counts in the
old PM it is not worth the effort tuning it)
Reviewers: davidxl, silvas
Subscribers: mgorny, mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D41604
llvm-svn: 322110
Because of potential UB (known bits conflicts with an llvm.assume),
we have to check rather than assert here because InstSimplify doesn't
kill the compare:
https://bugs.llvm.org/show_bug.cgi?id=35846
llvm-svn: 322104
EarlyCSE did not try to salvage debug info during erasing of instructions.
This change fixes it.
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D41496
llvm-svn: 322083
This is an attempt of fixing PR35807.
Due to the non-standard definition of dominance in LLVM, where uses in
unreachable blocks are dominated by anything, you can have, in an
unreachable block:
%patatino = OP1 %patatino, CONSTANT
When `SimplifyInstruction` receives a PHI where an incoming value is of
the aforementioned form, in some cases, loops indefinitely.
What I propose here instead is keeping track of the incoming values
from unreachable blocks, and replacing them with undef. It fixes this
case, and it seems to be good regardless (even if we can't prove that
the value is constant, as it's coming from an unreachable block, we
can ignore it).
Differential Revision: https://reviews.llvm.org/D41812
llvm-svn: 322006
There is precedence for factorization transforms in instcombine for FP ops with fast-math.
We also have similar logic in foldSPFofSPF().
It would take more work to add this to reassociate because that's specialized for binops,
and min/max are not binops (or even single instructions). Also, I don't have evidence that
larger min/max trees than this exist in real code, but if we find that's true, we might
want to reorganize where/how we do this optimization.
In the motivating example from https://bugs.llvm.org/show_bug.cgi?id=35717 , we have:
int test(int xc, int xm, int xy) {
int xk;
if (xc < xm)
xk = xc < xy ? xc : xy;
else
xk = xm < xy ? xm : xy;
return xk;
}
This patch solves that problem because we recognize more min/max patterns after rL321672
https://rise4fun.com/Alive/Qjnehttps://rise4fun.com/Alive/3yg
Differential Revision: https://reviews.llvm.org/D41603
llvm-svn: 321998
Summary:
Fixes the bug with incorrect handling of InsertValue|InsertElement
instrucions in SLP vectorizer. Currently, we may use incorrect
ExtractElement instructions as the operands of the original
InsertValue|InsertElement instructions.
Reviewers: mkuper, hfinkel, RKSimon, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41767
llvm-svn: 321994
Summary:
If the vectorized value is marked as extra reduction argument, its users
are not considered as external users. Patch fixes this.
Reviewers: mkuper, hfinkel, RKSimon, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41786
llvm-svn: 321993
The approach was never discussed, I wasn't able to reproduce this
non-determinism, and the original author went AWOL.
After a discussion on the ML, Philip suggested to revert this.
llvm-svn: 321974
Another small step forward to move VPlan stuff outside of LoopVectorize.cpp.
VPlanBuilder.h is renamed to LoopVectorizationPlanner.h
LoopVectorizationPlanner class is moved from LoopVectorize.cpp to
LoopVectorizationPlanner.h LoopVectorizationCostModel::VectorizationFactor
class is moved to LoopVectorizationPlanner.h (used by the planner class) ---
this needs further streamlining work in later patches and thus all I did was
take it out of the CostModel class and moved to the header file. The callback
function had to stay inside LoopVectorize.cpp since it calls an
InnerLoopVectorizer member function declared in it. Next Steps: Make
InnerLoopVectorizer, LoopVectorizationCostModel, and other classes more modular
and more aligned with VPlan direction, in small increments.
Previous step was: r320900 (https://reviews.llvm.org/D41045)
Patch by Hideki Saito, thanks!
Differential Revision: https://reviews.llvm.org/D41420
llvm-svn: 321962
In addition to target-dependent attributes, we can also preserve a
white-listed subset of target independent function attributes. The white-list
excludes problematic attributes, most prominently:
* attributes related to memory accesses, as alloca instructions
could be moved in/out of the extracted block
* control-flow dependent attributes, like no_return or thunk, as the
relerelevant instructions might or might not get extracted.
Thanks @efriedma and @aemerson for providing a set of attributes that cannot be
propagated.
Reviewers: efriedma, davidxl, davide, silvas
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D41334
llvm-svn: 321961
If the varargs are not accessed by a function, we can inline the
function.
Reviewers: dblaikie, chandlerc, davide, efriedma, rnk, hfinkel
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D41335
llvm-svn: 321940
In the minimal case, this won't remove instructions, but it still improves
uses of existing values.
In the motivating example from PR35834, it does remove instructions, and
sets that case up to be optimized by something like D41603:
https://reviews.llvm.org/D41603
llvm-svn: 321936
Having a single call to findDbgUsers() allows salvageDebugInfo() to
return earlier.
Differential Revision: https://reviews.llvm.org/D41787
llvm-svn: 321915
Besides the bug of omitting the inverse transform of max(~a, ~b) --> ~min(a, b),
the use checking and operand creation were off. We were potentially creating
repeated identical instructions of existing values. This led to infinite
looping after I added the extra folds.
By using the simpler m_Not matcher and not creating new 'not' ops for a and b,
we avoid that problem. It's possible that not using IsFreeToInvert() here is
more limiting than the simpler matcher, but there are no tests for anything
more exotic. It's also possible that we should relax the use checking further
to handle a case like PR35834:
https://bugs.llvm.org/show_bug.cgi?id=35834
...but we can make that a follow-up if it is needed.
llvm-svn: 321882
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 321825
This came up during discussions in llvm-commits for
rL321653: Check for unreachable preds before updating LI in
UpdateAnalysisInformation
The assert provides hints to passes to require both DT and LI if we plan on
updating LI through this function.
Tests run: make check
llvm-svn: 321805
The work order was changed in r228186 from SCC order
to RPO with an arbitrary sorting function. The sorting
function attempted to move inner loop nodes earlier. This
was was apparently relying on an assumption that every block
in a given loop / the same loop depth would be seen before
visiting another loop. In the broken testcase, a block
outside of the loop was encountered before moving onto
another block in the same loop. The testcase would then
structurize such that one blocks unconditional successor
could never be reached.
Revert to plain RPO for the analysis phase. This fixes
detecting edges as backedges that aren't really.
The processing phase does use another visited set, and
I'm unclear on whether the order there is as important.
An arbitrary order doesn't work, and triggers some infinite
loops. The reversed RPO list seems to work and is closer
to the order that was used before, minus the arbitary
custom sorting.
A few of the changed tests now produce smaller code,
and a few are slightly worse looking.
llvm-svn: 321751
Summary:
We are incorrectly updating the LI when loop-simplify generates
dedicated exit blocks for a loop. The issue is that there's an implicit
assumption that the Preds passed into UpdateAnalysisInformation are
reachable. However, this is not true and breaks LI by incorrectly
updating the header of a loop.
One such case is when we generate dedicated exits when the exit block is
a landing pad (through SplitLandingPadPredecessors). There maybe other
cases as well, since we do not guarantee that Preds passed in are
reachable basic blocks.
The added test case shows how loop-simplify breaks LI for the outer loop (and DT in turn)
after we try to generate the LoopSimplifyForm.
Reviewers: davide, chandlerc, sanjoy
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41519
llvm-svn: 321653
`RewriteStatepointsForGC` iterates over function blocks and their predecessors
in order of declaration. One of outcomes of this is that callsites are placed in
arbitrary order which has nothing to do with travelsar order.
On the other hand, function `recomputeLiveInValues` asserts that bases are
added to `Info.PointerToBase` before their deried pointers are updated. But
if call sites are processed in order different from RPOT, this is not necessarily
true. We cannot guarantee that the base was placed there before every
pointer derived from it. All we can guarantee is that this base was marked as
known base by this point.
This patch replaces the fact that we assert from checking that the base was
added to the map with assert that the base was marked as known base.
Differential Revision: https://reviews.llvm.org/D41593
llvm-svn: 321517
This reverts r321138. It seems there are still underlying issues with
memdep. PR35519 seems to still be present if debug info is enabled. We
end up losing a memcpy. Somehow during store to memset merging, we
insert the memset after the memcpy or fail to update the memdep analysis
to account for the newly inserted memset of a pair.
Reduced test case:
#include <assert.h>
#include <stdio.h>
#include <string>
#include <utility>
#include <vector>
void do_push_back(
std::vector<std::pair<std::string, std::vector<std::string>>>* crls) {
crls->push_back(std::make_pair(std::string(), std::vector<std::string>()));
}
int __attribute__((optnone)) main() {
// Put some data in the vector and then remove it so we take the push_back
// fast path.
std::vector<std::pair<std::string, std::vector<std::string>>> crl_set;
crl_set.push_back({"asdf", {}});
crl_set.pop_back();
printf("first word in vector storage: %p\n", *(void**)crl_set.data());
// Do the push_back which may fail to initialize the data.
do_push_back(&crl_set);
auto* first = &crl_set.back().first;
printf("first word in vector storage (should be zero): %p\n",
*(void**)crl_set.data());
assert(first->empty());
puts("ok");
}
Compile with libc++, enable optimizations, and enable debug info:
$ clang++ -stdlib=libc++ -g -O2 t.cpp -o t.exe -Wl,-rpath=llvm/build/lib
This program will assert with this change.
llvm-svn: 321510
By following the single predecessors of the predecessors of the call
site, we do not need to restrict the control flow.
Reviewed By: junbuml, davide
Differential Revision: https://reviews.llvm.org/D40729
llvm-svn: 321413
This code was originally removed and replace with an assertion
because believed unnecessary. It turns out there was simply
no test coverage for this case, and the constant folder doesn't
yet know about patterns like `br undef %label1, %label2`.
Presumably at some point the constant folder might learn about
these patterns, but it's a broader change.
A testcase will be added to make sure this doesn't regress again
in the future.
Fixes PR35723.
llvm-svn: 321402
If after if-conversion, most of the instructions in this new BB construct a long and slow dependence chain, it may be slower than cmp/branch, even if the branch has a high miss rate, because the control dependence is transformed into data dependence, and control dependence can be speculated, and thus, the second part can execute in parallel with the first part on modern OOO processor.
This patch checks for the long dependence chain, and give up if-conversion if find one.
Differential Revision: https://reviews.llvm.org/D39352
llvm-svn: 321377
Summary:
This replaces calls to getEntryCount().hasValue() with hasProfileData
that does the same thing. This refactoring is useful to do before adding
synthetic function entry counts but also a useful cleanup IMO even
otherwise. I have used hasProfileData instead of hasRealProfileData as
David had earlier suggested since I think profile implies "real" and I
use the phrase "synthetic entry count" and not "synthetic profile count"
but I am fine calling it hasRealProfileData if you prefer.
Reviewers: davidxl, silvas
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41461
llvm-svn: 321331
If a block has N predecessors, then the current algorithm will try to
sink common code to this block N times (whenever we visit a
predecessor). Every attempt to sink the common code includes going
through all predecessors, so the complexity of the algorithm becomes
O(N^2).
With this patch we try to sink common code only when we visit the block
itself. With this, the complexity goes down to O(N).
As a side effect, the moment the code is sunk is slightly different than
before (the order of simplifications has been changed), that's why I had
to adjust two tests (note that neither of the tests is supposed to test
SimplifyCFG):
* test/CodeGen/AArch64/arm64-jumptable.ll - changes in this test mimic
the changes that previous implementation of SimplifyCFG would do.
* test/CodeGen/ARM/avoid-cpsr-rmw.ll - in this test I disabled common
code sinking by a command line flag.
llvm-svn: 321236
This patch modifies the indirect call promotion utilities by exposing and using
an unconditional call promotion interface. The unconditional promotion
interface (i.e., call promotion without creating an if-then-else) can be used
if it's known that an indirect call has only one possible callee. The existing
conditional promotion interface uses this unconditional interface to promote an
indirect call after it has been versioned and placed within the "then" block.
A consequence of unconditional promotion is that the fix-up operations for phi
nodes in the normal destination of invoke instructions are changed. This is
necessary because the existing implementation assumed that an invoke had been
versioned, creating a "merge" block where a return value bitcast could be
placed. In the new implementation, the edge between a promoted invoke's parent
block and its normal destination is split if needed to add a bitcast for the
return value. If the invoke is also versioned, the phi node merging the return
value of the promoted and original invoke instructions is placed in the "merge"
block.
Differential Revision: https://reviews.llvm.org/D40751
llvm-svn: 321210
Summary: Very similar to AddressSanitizer, with the exception of the error type encoding.
Reviewers: kcc, alekseyshl
Subscribers: cfe-commits, kubamracek, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D41417
llvm-svn: 321203
canVectorize is only checking if the loop has a normalized pre-header if DoExtraAnalysis is true.
This doesn't make sense to me because reporting analysis information shouldn't alter legality
checks. This is probably the result of a last minute minor change before committing (?).
Patch by Diego Caballero.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D40973
llvm-svn: 321172
This teaches memcpyopt to make a non-local memdep query when a local query
indicates that the dependency is non-local. This notably allows it to
eliminate many more llvm.memcpy calls in common Rust code, often by 20-30%.
This is r319482 and r319483, along with fixes for PR35519: fix the
optimization that merges stores into memsets to preserve cached memdep
info, and fix memdep's non-local caching strategy to not assume that larger
queries are always more conservative than smaller ones.
Fixes PR28958 and PR35519.
Differential Revision: https://reviews.llvm.org/D40802
llvm-svn: 321138
PRE in JumpThreading should not be able to hoist copy of non-speculable loads across
instructions that don't always transfer execution to their successors, otherwise they may
introduce an unsafe load which otherwise would not be executed.
The same problem for GVN was fixed as rL316975.
Differential Revision: https://reviews.llvm.org/D40347
llvm-svn: 321063
Summary:
In r277849, getEntryCount was changed to return None when the entry
count was 0, specifically for SamplePGO where it means no samples were
recorded. However, for instrumentation PGO a 0 entry count should be
returned directly, since it does mean that the function was completely
cold. Otherwise we end up treating these functions conservatively
in isFunctionEntryCold() and isColdBB().
Instead, for SamplePGO use -1 when there are no samples, and change
getEntryCount to return None when the value is -1.
Reviewers: danielcdh, davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41307
llvm-svn: 321018
This patch introduce a switch to control splitting of non-whole-alloca slices with default off.
The switch will be default on again after fixing an issue reported in PR35657.
llvm-svn: 320958
If the loop operand type is int8 then there will be no residual loop for the
unknown size expansion. Dont create the residual-size and bytes-copied values
when they are not needed.
llvm-svn: 320929
We want to do this for 2 reasons:
1. Value tracking does not recognize the ashr variant, so it would fail to match for cases like D39766.
2. DAGCombiner does better at producing optimal codegen when we have the cmp+sel pattern.
More detail about what happens in the backend:
1. DAGCombiner has a generic transform for all targets to convert the scalar cmp+sel variant of abs
into the shift variant. That is the opposite of this IR canonicalization.
2. DAGCombiner has a generic transform for all targets to convert the vector cmp+sel variant of abs
into either an ABS node or the shift variant. That is again the opposite of this IR canonicalization.
3. DAGCombiner has a generic transform for all targets to convert the exact shift variants produced by #1 or #2
into an ISD::ABS node. Note: It would be an efficiency improvement if we had #1 go directly to an ABS node
when that's legal/custom.
4. The pattern matching above is incomplete, so it is possible to escape the intended/optimal codegen in a
variety of ways.
a. For #2, the vector path is missing the case for setlt with a '1' constant.
b. For #3, we are missing a match for commuted versions of the shift variants.
5. Therefore, this IR canonicalization can only help get us to the optimal codegen. The version of cmp+sel
produced by this patch will be recognized in the DAG and converted to an ABS node when possible or the
shift sequence when not.
6. In the following examples with this patch applied, we may get conditional moves rather than the shift
produced by the generic DAGCombiner transforms. The conditional move is created using a target-specific
decision for any given target. Whether it is optimal or not for a particular subtarget may be up for debate.
define i32 @abs_shifty(i32 %x) {
%signbit = ashr i32 %x, 31
%add = add i32 %signbit, %x
%abs = xor i32 %signbit, %add
ret i32 %abs
}
define i32 @abs_cmpsubsel(i32 %x) {
%cmp = icmp slt i32 %x, zeroinitializer
%sub = sub i32 zeroinitializer, %x
%abs = select i1 %cmp, i32 %sub, i32 %x
ret i32 %abs
}
define <4 x i32> @abs_shifty_vec(<4 x i32> %x) {
%signbit = ashr <4 x i32> %x, <i32 31, i32 31, i32 31, i32 31>
%add = add <4 x i32> %signbit, %x
%abs = xor <4 x i32> %signbit, %add
ret <4 x i32> %abs
}
define <4 x i32> @abs_cmpsubsel_vec(<4 x i32> %x) {
%cmp = icmp slt <4 x i32> %x, zeroinitializer
%sub = sub <4 x i32> zeroinitializer, %x
%abs = select <4 x i1> %cmp, <4 x i32> %sub, <4 x i32> %x
ret <4 x i32> %abs
}
> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=x86_64 -mattr=avx
> abs_shifty:
> movl %edi, %eax
> negl %eax
> cmovll %edi, %eax
> retq
>
> abs_cmpsubsel:
> movl %edi, %eax
> negl %eax
> cmovll %edi, %eax
> retq
>
> abs_shifty_vec:
> vpabsd %xmm0, %xmm0
> retq
>
> abs_cmpsubsel_vec:
> vpabsd %xmm0, %xmm0
> retq
>
> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=aarch64
> abs_shifty:
> cmp w0, #0 // =0
> cneg w0, w0, mi
> ret
>
> abs_cmpsubsel:
> cmp w0, #0 // =0
> cneg w0, w0, mi
> ret
>
> abs_shifty_vec:
> abs v0.4s, v0.4s
> ret
>
> abs_cmpsubsel_vec:
> abs v0.4s, v0.4s
> ret
>
> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=powerpc64le
> abs_shifty:
> srawi 4, 3, 31
> add 3, 3, 4
> xor 3, 3, 4
> blr
>
> abs_cmpsubsel:
> srawi 4, 3, 31
> add 3, 3, 4
> xor 3, 3, 4
> blr
>
> abs_shifty_vec:
> vspltisw 3, -16
> vspltisw 4, 15
> vsubuwm 3, 4, 3
> vsraw 3, 2, 3
> vadduwm 2, 2, 3
> xxlxor 34, 34, 35
> blr
>
> abs_cmpsubsel_vec:
> vspltisw 3, -16
> vspltisw 4, 15
> vsubuwm 3, 4, 3
> vsraw 3, 2, 3
> vadduwm 2, 2, 3
> xxlxor 34, 34, 35
> blr
>
Differential Revision: https://reviews.llvm.org/D40984
llvm-svn: 320921
Changes to the original scalar loop during LV code gen cause the return value
of Legal->isConsecutivePtr() to be inconsistent with the return value during
legal/cost phases (further analysis and information of the bug is in D39346).
This patch is an alternative fix to PR34965 following the CM_Widen approach
proposed by Ayal and Gil in D39346. It extends InstWidening enum with
CM_Widen_Reverse to properly record the widening decision for consecutive
reverse memory accesses and, consequently, get rid of the
Legal->isConsetuviePtr() call in LV code gen. I think this is a simpler/cleaner
solution to PR34965 than the one in D39346.
Fixes PR34965.
Patch by Diego Caballero, thanks!
Differential Revision: https://reviews.llvm.org/D40742
llvm-svn: 320913
When unsafe algerbra is allowed calls to cabs(r) can be replaced by:
sqrt(creal(r)*creal(r) + cimag(r)*cimag(r))
Patch by Paul Walker, thanks!
Differential Revision: https://reviews.llvm.org/D40069
llvm-svn: 320901
This is a small step forward to move VPlan stuff to where it should belong (i.e., VPlan.*):
1. VP*Recipe classes in LoopVectorize.cpp are moved to VPlan.h.
2. Many of VP*Recipe::print() and execute() definitions are still left in
LoopVectorize.cpp since they refer to things declared in LoopVectorize.cpp. To
be moved to VPlan.cpp at a later time.
3. InterleaveGroup class is moved from anonymous namespace to llvm namespace.
Referencing it in anonymous namespace from VPlan.h ended up in warning.
Patch by Hideki Saito, thanks!
Differential Revision: https://reviews.llvm.org/D41045
llvm-svn: 320900
Summary:
This implements a missing feature to allow importing of aliases, which
was previously disabled because alias cannot be available_externally.
We instead import an alias as a copy of its aliasee.
Some additional work was required in the IndexBitcodeWriter for the
distributed build case, to ensure that the aliasee has a value id
in the distributed index file (i.e. even when it is not being
imported directly).
This is a performance win in codes that have many aliases, e.g. C++
applications that have many constructor and destructor aliases.
Reviewers: pcc
Subscribers: mehdi_amini, inglorion, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D40747
llvm-svn: 320895
This recommits r320823 reverted due to the test failure in sink-foldable.ll and
an unused variable. Added "REQUIRES: aarch64-registered-target" in the test
and removed unused variable.
Original commit message:
Continue trying to sink an instruction if its users in the loop is foldable.
This will allow the instruction to be folded in the loop by decoupling it from
the user outside of the loop.
Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier
Reviewed By: hfinkel
Subscribers: javed.absar, bmakam, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D37076
llvm-svn: 320858
The original memcpy expansion inserted the loop basic block inbetween
the 2 new basic blocks created by splitting the original block the memcpy
call was in. This commit makes the new memcpy expansion do the same to keep the
layout of the IR matching between the old and new implementations.
Differential Review: https://reviews.llvm.org/D41197
llvm-svn: 320848
This recommit r320823 after fixing a test failure.
Original commit message:
Continue trying to sink an instruction if its users in the loop is foldable.
This will allow the instruction to be folded in the loop by decoupling it from
the user outside of the loop.
Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier
Reviewed By: hfinkel
Subscribers: javed.absar, bmakam, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D37076
llvm-svn: 320833
Summary:
Continue trying to sink an instruction if its users in the loop is foldable.
This will allow the instruction to be folded in the loop by decoupling it from
the user outside of the loop.
Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier
Reviewed By: hfinkel
Subscribers: javed.absar, bmakam, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D37076
llvm-svn: 320823
Summary:
The port is nearly straightforward.
The only complication is related to the analyses handling,
since one of the analyses used in this module pass is domtree,
which is a function analysis. That requires asking for the results
of each function and disallows a single interface for run-on-module
pass action.
Decided to copy-paste the main body of this pass.
Most of its code is requesting analyses anyway, so not that much
of a copy-paste.
The rest of the code movement is to transform all the implementation
helper functions like stripNonValidData into non-member statics.
Extended all the related LLVM tests with new-pass-manager use.
No failures.
Reviewers: sanjoy, anna, reames
Reviewed By: anna
Subscribers: skatkov, llvm-commits
Differential Revision: https://reviews.llvm.org/D41162
llvm-svn: 320796
This should solve:
https://bugs.llvm.org/show_bug.cgi?id=34603
...by preventing SimplifyCFG from altering redundant instructions before early-cse has a chance to run.
It changes the default (canonical-forming) behavior of SimplifyCFG, so we're only doing the
sinking transform later in the optimization pipeline.
Differential Revision: https://reviews.llvm.org/D38566
llvm-svn: 320749
In SLPVectorizer, the vector build instructions (insertvalue for aggregate type) is passed to BoUpSLP.buildTree, it is treated as UserIgnoreList, so later in cost estimation, the cost of these instructions are not counted.
For aggregate value, later usage are more likely to be done in scalar registers, either used as individual scalars or used as a whole for function call or return value. Ignore scalar extraction instructions may cause too aggressive vectorization for aggregate values, and slow down performance. So for vectorization of aggregate value, the scalar extraction instructions are required in cost estimation.
Differential Revision: https://reviews.llvm.org/D41139
llvm-svn: 320736
Summary:
Passing AliasAnalysis results instead of nullptr appears to work just fine.
A couple new-pass-manager tests updated to align with new order of analyses.
Reviewers: chandlerc, spatel, craig.topper
Reviewed By: chandlerc
Subscribers: mehdi_amini, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D41203
llvm-svn: 320687
D30041 extended SCEVPredicateRewriter to improve handling of Phi nodes whose
update chain involves casts; PSCEV can now build an AddRecurrence for some
forms of such phi nodes, under the proper runtime overflow test. This means
that we can identify such phi nodes as an induction, and the loop-vectorizer
can now vectorize such inductions, however inefficiently. The vectorizer
doesn't know that it can ignore the casts, and so it vectorizes them.
This patch records the casts in the InductionDescriptor, so that they could
be marked to be ignored for cost calculation (we use VecValuesToIgnore for
that) and ignored for vectorization/widening/scalarization (i.e. treated as
TriviallyDead).
In addition to marking all these casts to be ignored, we also need to make
sure that each cast is mapped to the right vector value in the vector loop body
(be it a widened, vectorized, or scalarized induction). So whenever an
induction phi is mapped to a vector value (during vectorization/widening/
scalarization), we also map the respective cast instruction (if exists) to that
vector value. (If the phi-update sequence of an induction involves more than one
cast, then the above mapping to vector value is relevant only for the last cast
of the sequence as we allow only the "last cast" to be used outside the
induction update chain itself).
This is the last step in addressing PR30654.
llvm-svn: 320672
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 320612
w.r.t. the paper
"A Practical Improvement to the Partial Redundancy Elimination in SSA Form"
(https://sites.google.com/site/jongsoopark/home/ssapre.pdf)
Proper dominance check was missing here, so having a loopinfo should not be required.
Committing this diff as this fixes the bug, if there are
further concerns, I'll be happy to work on them.
Differential Revision: https://reviews.llvm.org/D39781
llvm-svn: 320607
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.
This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
Reviewed By: Ayal
Subscribers: mgrang, dcaballe, hans, mzolotukhin
Differential Revision: https://reviews.llvm.org/D36130
llvm-svn: 320548
Summary:
This change makes the call site creation more general if any of the
arguments is predicated on a condition in the call site's predecessors.
If we find a callsite, that potentially can be split, we collect the set
of conditions for the call site's predecessors (currently only 2
predecessors are allowed). To do that, we traverse each predecessor's
predecessors as long as it only has single predecessors and record the
condition, if it is relevant to the call site. For each condition, we
also check if the condition is taken or not. In case it is not taken,
we record the inverse predicate.
We use the recorded conditions to create the new call sites and split
the basic block.
This has 2 benefits: (1) it is slightly easier to see what is going on
(IMO) and (2) we can easily extend it to handle more complex control
flow.
Reviewers: davidxl, junbuml
Reviewed By: junbuml
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40728
llvm-svn: 320547
Summary: This brings CPU overhead on bzip2 down from 5.5x to 2x.
Reviewers: kcc, alekseyshl
Subscribers: kubamracek, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D41137
llvm-svn: 320538
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320525
This algorithm (explained more in the source code) takes into account
global redundancies by building a "pair map" to find common subexprs.
The primary motivation of this is to handle situations like
foo = (a * b) * c
bar = (a * d) * c
where we currently don't identify that "a * c" is redundant.
Accordingly, it prioritizes the emission of a * c so that CSE
can remove the redundant calculation later.
Does not change the actual reassociation algorithm -- only the
order in which the reassociated operand chain is reconstructed.
Gives ~1.5% floating point math instruction count reduction on
a large offline suite of graphics shaders.
llvm-svn: 320515
Summary:
The PGO gen/use passes currently fail with an assert failure if there's a
critical edge whose source is an IndirectBr instruction and that edge
needs to be instrumented.
To avoid this in certain cases, split IndirectBr critical edges in the PGO
gen/use passes. This works for blocks with single indirectbr predecessors,
but not for those with multiple indirectbr predecessors (splitting an
IndirectBr critical edge isn't always possible.)
Reviewers: davidxl, xur
Reviewed By: davidxl
Subscribers: efriedma, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D40699
llvm-svn: 320511
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320510
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320499
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320496
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320488
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320483
Summary:
Currently, in InstCombineLoadStoreAlloca, we have simplification
rules for the following cases:
1. load off a null
2. load off a GEP with null base
3. store to a null
This patch adds support for the fourth case which is store into a
GEP with null base. Since this is UB as well (and directly analogous to
the load off a GEP with null base), we can substitute the stored val
with undef in instcombine, so that SimplifyCFG can optimize this code
into unreachable code.
Note: Right now, simplifyCFG hasn't been taught about optimizing
this to unreachable and adding an llvm.trap (this is already done for
the above 3 cases).
Reviewers: majnemer, hfinkel, sanjoy, davide
Reviewed by: sanjoy, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41026
llvm-svn: 320480
VecValuesToIgnore holds values that will not appear in the vectorized loop.
We should therefore ignore their cost when VF > 1.
Differential Revision: https://reviews.llvm.org/D40883
llvm-svn: 320463
Summary:
This solves PR35616.
We don't want the compiler to generate different code when we compile
with/without -g, so we now ignore debug intrinsics when determining if
the optimization can trigger or not.
Reviewers: junbuml
Subscribers: davide, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D41068
llvm-svn: 320460
The tests fail (opt asserts) on Windows.
> Summary:
> If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
> &V2)))), bitcast)`, but the load is used in other instructions, it leads
> to looping in InstCombiner. Patch adds additional check that all users
> of the load instructions are stores and then replaces all uses of load
> instruction by the new one with new type.
>
> Reviewers: RKSimon, spatel, majnemer
>
> Subscribers: llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320421
The function stack poisioner conditionally stores local variables
either in an alloca or in malloc'ated memory, which has the
unfortunate side-effect, that the actual address of the variable is
only materialized when the variable is accessed, which means that
those variables are mostly invisible to the debugger even when
compiling without optimizations.
This patch stores the address of the local stack base into an alloca,
which can be referred to by the debug info and is available throughout
the function. This adds one extra pointer-sized alloca to each stack
frame (but mem2reg can optimize it away again when optimizations are
enabled, yielding roughly the same debug info quality as before in
optimized code).
rdar://problem/30433661
Differential Revision: https://reviews.llvm.org/D41034
llvm-svn: 320415
Summary:
If we have pattern `store (load(bitcast(select (cmp(V1, V2), &V1,
&V2)))), bitcast)`, but the load is used in other instructions, it leads
to looping in InstCombiner. Patch adds additional check that all users
of the load instructions are stores and then replaces all uses of load
instruction by the new one with new type.
Reviewers: RKSimon, spatel, majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41072
llvm-svn: 320407
This patch introduces getShadowOriginPtr(), a method that obtains both the shadow and origin pointers for an address as a Value pair.
The existing callers of getShadowPtr() and getOriginPtr() are updated to use getShadowOriginPtr().
The rationale for this change is to simplify KMSAN instrumentation implementation.
In KMSAN origins tracking is always enabled, and there's no direct mapping between the app memory and the shadow/origin pages.
Both the shadow and the origin pointer for a given address are obtained by calling a single runtime hook from the instrumentation,
therefore it's easier to work with those pointers together.
Reviewed at https://reviews.llvm.org/D40835.
llvm-svn: 320373
Summary:
Reuse the Linux new mapping as it is.
Sponsored by <The NetBSD Foundation>
Reviewers: joerg, eugenis, vitalybuka
Reviewed By: vitalybuka
Subscribers: llvm-commits, #sanitizers
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D41022
llvm-svn: 320219
Summary:
This is LLVM instrumentation for the new HWASan tool. It is basically
a stripped down copy of ASan at this point, w/o stack or global
support. Instrumenation adds a global constructor + runtime callbacks
for every load and store.
HWASan comes with its own IR attribute.
A brief design document can be found in
clang/docs/HardwareAssistedAddressSanitizerDesign.rst (submitted earlier).
Reviewers: kcc, pcc, alekseyshl
Subscribers: srhines, mehdi_amini, mgorny, javed.absar, eraman, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D40932
llvm-svn: 320217
Summary:
If a partially inlined function has debug info, we have to add debug
locations to the call instruction calling the outlined function.
We use the debug location of the first instruction in the outlined
function, as the introduced call transfers control to this statement and
there is no other equivalent line in the source code.
We also use the same debug location for the branch instruction added
to jump from artificial entry block for the outlined function, which just
jumps to the first actual basic block of the outlined function.
Reviewers: davide, aprantl, rriddle, dblaikie, danielcdh, wmi
Reviewed By: aprantl, rriddle, danielcdh
Subscribers: eraman, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D40413
llvm-svn: 320199
Causes unexpected memory issue with New PM this time.
The new PM invalidates BPI but not BFI, leaving the
reference to BPI from BFI invalid.
Abandon this patch. There is a more general solution
which also handles runtime infinite loop (but not statically).
llvm-svn: 320180
Summary:
If we have the code like this:
```
float a, b;
a = std::max(a ,b);
```
it is converted into something like this:
```
%call = call dereferenceable(4) float* @_ZSt3maxIfERKT_S2_S2_(float* nonnull dereferenceable(4) %a.addr, float* nonnull dereferenceable(4) %b.addr)
%1 = bitcast float* %call to i32*
%2 = load i32, i32* %1, align 4
%3 = bitcast float* %a.addr to i32*
store i32 %2, i32* %3, align 4
```
After inlinning this code is converted to the next:
```
%1 = load float, float* %a.addr
%2 = load float, float* %b.addr
%cmp.i = fcmp fast olt float %1, %2
%__b.__a.i = select i1 %cmp.i, float* %a.addr, float* %b.addr
%3 = bitcast float* %__b.__a.i to i32*
%4 = load i32, i32* %3, align 4
%5 = bitcast float* %arrayidx to i32*
store i32 %4, i32* %5, align 4
```
This pattern is not recognized as minmax pattern.
Patch solves this problem by converting sequence
```
store (bitcast, (load bitcast (select ((cmp V1, V2), &V1, &V2))))
```
to a sequence
```
store (,load (select((cmp V1, V2), &V1, &V2)))
```
After this the code is recognized as minmax pattern.
Reviewers: RKSimon, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40304
llvm-svn: 320157
In more recent Linux kernels with 47 bit VMAs the layout of virtual memory
for powerpc64 changed causing the address sanitizer to not work properly. This
patch adds support for 47 bit VMA kernels for powerpc64 and fixes up test
cases.
https://reviews.llvm.org/D40907
There is an associated patch for compiler-rt.
Tested on several 4.x and 3.x kernel releases.
llvm-svn: 320109
Summary:
Make enum ModRefInfo an enum class. Changes to ModRefInfo values should
be done using inline wrappers.
This should prevent future bit-wise opearations from being added, which can be more error-prone.
Reviewers: sanjoy, dberlin, hfinkel, george.burgess.iv
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40933
llvm-svn: 320107
As a new access is generated spanning across multiple fields, we need to
propagate alias info from all the fields to form the most generic alias info.
rdar://35602528
Differential Revision: https://reviews.llvm.org/D40617
llvm-svn: 319979
This patch factors out the main code transformation utilities in the pgo-driven
indirect call promotion pass and places them in Transforms/Utils. The change is
intended to be a non-functional change, letting non-pgo-driven passes share a
common implementation with the existing pgo-driven pass.
The common utilities are used to conditionally promote indirect call sites to
direct call sites. They perform the underlying transformation, and do not
consider profile information. The pgo-specific details (e.g., the computation
of branch weight metadata) have been left in the indirect call promotion pass.
Differential Revision: https://reviews.llvm.org/D40658
llvm-svn: 319963
Summary:
There is no need to replace the original call instruction if no
VarArgs need to be forwarded.
Reviewers: davide, rnk, majnemer, efriedma
Reviewed By: efriedma
Subscribers: eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D40412
llvm-svn: 319947
This caused PR35519.
> [memcpyopt] Teach memcpyopt to optimize across basic blocks
>
> This teaches memcpyopt to make a non-local memdep query when a local query
> indicates that the dependency is non-local. This notably allows it to
> eliminate many more llvm.memcpy calls in common Rust code, often by 20-30%.
>
> Fixes PR28958.
>
> Differential Revision: https://reviews.llvm.org/D38374
>
> [memcpyopt] Commit file missed in r319482.
>
> This change was meant to be included with r319482 but was accidentally
> omitted.
llvm-svn: 319873
Summary:
The aim is to make ModRefInfo checks and changes more intuitive
and less error prone using inline methods that abstract the bit operations.
Ideally ModRefInfo would become an enum class, but that change will require
a wider set of changes into FunctionModRefBehavior.
Reviewers: sanjoy, george.burgess.iv, dberlin, hfinkel
Subscribers: nlopes, llvm-commits
Differential Revision: https://reviews.llvm.org/D40749
llvm-svn: 319821
This uses ConstantRange::makeGuaranteedNoWrapRegion's newly-added handling for subtraction to allow CVP to remove some subtraction overflow checks.
Differential Revision: https://reviews.llvm.org/D40039
llvm-svn: 319807
Summary:
A true or false result is expected from a comparison, but it seems the possibility of undef was overlooked, which could lead to a failed assert. This is fixed by this patch by bailing out if we encounter undef.
The bug is old and the assert has been there since the end of 2014, so it seems this is unusual enough to forego optimization.
Patch by JesperAntonsson.
Reviewers: spatel, eeckstein, hans
Reviewed By: hans
Subscribers: uabelho, llvm-commits
Differential Revision: https://reviews.llvm.org/D40639
llvm-svn: 319768
Summary:
Move splitIndirectCriticalEdges() from CodeGenPrepare to BasicBlockUtils.h so
that it can be called from other places.
Reviewers: davidxl
Reviewed By: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40750
llvm-svn: 319689
(This reapplies r314253. r314253 was reverted on r314482 because of a
correctness regression on P100, but that regression was identified to be
something else.)
Summary:
Don't bail out on constant divisors for divisions that can be narrowed without
introducing control flow . This gives us a 32 bit multiply instead of an
emulated 64 bit multiply in the generated PTX assembly.
Reviewers: jlebar
Subscribers: jholewinski, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38265
llvm-svn: 319677
Summary:
Currently, we only support predication for forward loops with step
of 1. This patch enables loop predication for reverse or
countdownLoops, which satisfy the following conditions:
1. The step of the IV is -1.
2. The loop has a singe latch as B(X) = X <pred>
latchLimit with pred as s> or u>
3. The IV of the guard is the decrement
IV of the latch condition (Guard is: G(X) = X-1 u< guardLimit).
This patch was downstream for a while and is the last series of patches
that's from our LP implementation downstream.
Reviewers: apilipenko, mkazantsev, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40353
llvm-svn: 319659
Turns out we can have comparisons which are indirect users of the induction variable that we can make invariant. In this case, there is no loop invariant value contributing and we'd fail an assert.
The test case was found by a java fuzzer and reduced. It's a real cornercase. You have to have a static loop which we've already proven only executes once, but haven't broken the backedge on, and an inner phi whose result can be constant folded by SCEV using exit count reasoning but not proven by isKnownPredicate. To my knowledge, only the fuzzer has hit this case.
llvm-svn: 319583
It causes builds to fail with "Instruction does not dominate all uses" (PR35497).
> Patch tries to improve vectorization of the following code:
>
> void add1(int * __restrict dst, const int * __restrict src) {
> *dst++ = *src++;
> *dst++ = *src++ + 1;
> *dst++ = *src++ + 2;
> *dst++ = *src++ + 3;
> }
> Allows to vectorize even if the very first operation is not a binary add, but just a load.
>
> Fixed issues related to previous commit.
>
> Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev
>
> Reviewed By: ABataev, RKSimon
>
> Subscribers: llvm-commits, RKSimon
>
> Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 319550
Summary:
A true or false result is expected from a comparison, but it seems the possibility of undef was overlooked, which could lead to a failed assert. This is fixed by this patch by bailing out if we encounter undef.
The bug is old and the assert has been there since the end of 2014, so it seems this is unusual enough to forego optimization.
Patch by: JesperAntonsson
Reviewers: spatel, eeckstein, hans
Reviewed By: hans
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40639
llvm-svn: 319537
Patch tries to improve vectorization of the following code:
void add1(int * __restrict dst, const int * __restrict src) {
*dst++ = *src++;
*dst++ = *src++ + 1;
*dst++ = *src++ + 2;
*dst++ = *src++ + 3;
}
Allows to vectorize even if the very first operation is not a binary add, but just a load.
Fixed issues related to previous commit.
Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev
Reviewed By: ABataev, RKSimon
Subscribers: llvm-commits, RKSimon
Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 319531
These command line options are not intended for public use, and often
don't even make sense in the context of a particular tool anyway. About
90% of them are already hidden, but when people add new options they
forget to hide them, so if you were to make a brand new tool today, link
against one of LLVM's libraries, and run tool -help you would get a
bunch of junk that doesn't make sense for the tool you're writing.
This patch hides these options. The real solution is to not have
libraries defining command line options, but that's a much larger effort
and not something I'm prepared to take on.
Differential Revision: https://reviews.llvm.org/D40674
llvm-svn: 319505
If the thin module has no references to an internal global in the
merged module, we need to make sure to preserve that property if the
global is a member of a comdat group, as otherwise promotion can end
up adding global symbols to the comdat, which is not allowed.
This situation can arise if the external global in the thin module
has dead constant users, which would cause use_empty() to return
false and would cause us to try to promote it. To prevent this from
happening, discard the dead constant users before asking whether a
global is empty.
Differential Revision: https://reviews.llvm.org/D40593
llvm-svn: 319494
This teaches memcpyopt to make a non-local memdep query when a local query
indicates that the dependency is non-local. This notably allows it to
eliminate many more llvm.memcpy calls in common Rust code, often by 20-30%.
Fixes PR28958.
Differential Revision: https://reviews.llvm.org/D38374
llvm-svn: 319482
Currently, SROA splits loads and stores only when they are accessing the whole alloca.
This patch relaxes this limitation to allow splitting a load/store if all other loads and stores to the alloca are disjoint to or fully included in the current load/store. If there is no other load or store that crosses the boundary of the current load/store, the current splitting implementation works as is.
The whole-alloca loads and stores meet this new condition and so they are still splittable.
Here is a simplified motivating example.
struct record {
long long a;
int b;
int c;
};
int func(struct record r) {
for (int i = 0; i < r.c; i++)
r.b++;
return r.b;
}
When updating r.b (or r.c as well), LLVM generates redundant instructions on some platforms (such as x86_64, ppc64); here, r.b and r.c are packed into one 64-bit GPR when the struct is passed as a method argument.
With this patch, the above example is compiled into only few instructions without loop.
Without the patch, unnecessary loop-carried dependency is introduced by SROA and the loop cannot be eliminated by the later optimizers.
Differential Revision: https://reviews.llvm.org/D32998
llvm-svn: 319407
Support for outlining multiple regions of each function is added, as well as some basic heuristics to determine which regions are good to outline. Outline candidates limited to regions that are single-entry & single-exit. We also avoid outlining regions that produce live-exit variables, which may inhibit some forms of code motion (like commoning).
Fallback to the regular partial inlining scheme is retained when either i) no regions are identified for outlining in the function, or ii) the outlined function could not be inlined in any of its callers.
Differential Revision: https://reviews.llvm.org/D38190
llvm-svn: 319398
An alloca may be larger than a variable that is described to be stored
there. Don't create a dbg.value for fragments that are outside of the
variable.
This fixes PR35447.
https://bugs.llvm.org/show_bug.cgi?id=35447
llvm-svn: 319230
This is needed for cases when the memory access is not as big as the width of
the data type. For instance, storing i1 (1 bit) would be done in a byte (8
bits).
Using 'BitSize >> 3' (or '/ 8') would e.g. give the memory access of an i1 a
size of 0, which for instance makes alias analysis return NoAlias even when
it shouldn't.
There are no tests as this was done as a follow-up to the bugfix for the case
where this was discovered (r318824). This handles more similar cases.
Review: Björn Petterson
https://reviews.llvm.org/D40339
llvm-svn: 319173
The core idea is to (re-)introduce some redundancies where their cost is
hidden by the cost of materializing immediates for constant operands of
PHI nodes. When the cost of the redundancies is covered by this,
avoiding materializing the immediate has numerous benefits:
1) Less register pressure
2) Potential for further folding / combining
3) Potential for more efficient instructions due to immediate operand
As a motivating example, consider the remarkably different cost on x86
of a SHL instruction with an immediate operand versus a register
operand.
This pattern turns up surprisingly frequently, but is somewhat rarely
obvious as a significant performance problem.
The pass is entirely target independent, but it does rely on the target
cost model in TTI to decide when to speculate things around the PHI
node. I've included x86-focused tests, but any target that sets up its
immediate cost model should benefit from this pass.
There is probably more that can be done in this space, but the pass
as-is is enough to get some important performance on our internal
benchmarks, and should be generally performance neutral, but help with
more extensive benchmarking is always welcome.
One awkward part is that this pass has to be scheduled after
*everything* that can eliminate these kinds of redundancies. This
includes SimplifyCFG, GVN, etc. I'm open to suggestions about better
places to put this. We could in theory make it part of the codegen pass
pipeline, but there doesn't really seem to be a good reason for that --
it isn't "lowering" in any sense and only relies on pretty standard cost
model based TTI queries, so it seems to fit well with the "optimization"
pipeline model. Still, further thoughts on the pipeline position are
welcome.
I've also only implemented this in the new pass manager. If folks are
very interested, I can try to add it to the old PM as well, but I didn't
really see much point (my use case is already switched over to the new
PM).
I've tested this pretty heavily without issue. A wide range of
benchmarks internally show no change outside the noise, and I don't see
any significant changes in SPEC either. However, the size class
computation in tcmalloc is substantially improved by this, which turns
into a 2% to 4% win on the hottest path through tcmalloc for us, so
there are definitely important cases where this is going to make
a substantial difference.
Differential revision: https://reviews.llvm.org/D37467
llvm-svn: 319164
Summary:
I think we do not need to analyze debug intrinsics here, as they should
not impact codegen. This has 2 benefits: 1) slightly less work to do and
2) avoiding generating optimization remarks for converting calls to
debug intrinsics to tail calls, which are not really helpful for users.
Based on work by Sander de Smalen.
Reviewers: davide, trentxintong, aprantl
Reviewed By: aprantl
Subscribers: llvm-commits, JDevlieghere
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D40440
llvm-svn: 319158
This is to address a problem similar to those in D37460 for Scalar PRE. We should not
PRE across an instruction that may not pass execution to its successor unless it is safe
to speculatively execute it.
Differential Revision: https://reviews.llvm.org/D38619
llvm-svn: 319147
Revert "[SROA] Propagate !range metadata when moving loads."
Revert "[Mem2Reg] Clang-format unformatted parts of this file. NFCI."
Davide says they broke a bot.
llvm-svn: 319131
This tries to propagate !range metadata to a pre-existing load
when a load is optimized out. This is done instead of adding an
assume because converting loads to and from assumes creates a
lot of IR.
Patch by Ariel Ben-Yehuda.
Differential Revision: https://reviews.llvm.org/D37216
llvm-svn: 319096
enum TailCallKind { TCK_None = 0, TCK_Tail = 1, TCK_MustTail = 2,
TCK_NoTail = 3 };
TCK_NoTail is greater than TCK_Tail so taking the min does not do the
correct thing.
rdar://35639547
llvm-svn: 319075
MSan used to insert the shadow check of the store pointer operand
_after_ the shadow of the value operand has been written.
This happens to work in the userspace, as the whole shadow range is
always mapped. However in the kernel the shadow page may not exist, so
the bug may cause a crash.
This patch moves the address check in front of the shadow access.
llvm-svn: 318901
In a lambda where we expect to have result within bounds, add respective `nsw/nuw` flags to
help SCEV just in case if it fails to figure them out on its own.
Differential Revision: https://reviews.llvm.org/D40168
llvm-svn: 318898
After the dataflow algorithm proves that an argument is constant,
it replaces it value with the integer constant and drops the lattice
value associated to the DEF.
e.g. in the example we have @f() that's called twice:
call @f(undef, ...)
call @f(2, ...)
`undef` MEET 2 = 2 so we replace the argument and all its uses with
the constant 2.
Shortly after, tryToReplaceWithConstantRange() tries to get the lattice
value for the argument we just replaced, causing an assertion.
This function is a little peculiar as it runs when we're doing replacement
and not as part of the solver but still queries the solver.
The fix is that of checking whether we replaced the value already and
get a temporary lattice value for the constant.
Thanks to Zhendong Su for the report!
Fixes PR35357.
llvm-svn: 318817
Summary:
First step in adding MemorySSA as dependency for loop pass manager.
Adding the dependency under a flag.
New pass manager: MSSA pointer in LoopStandardAnalysisResults can be null.
Legacy and new pass manager: Use cl::opt EnableMSSALoopDependency. Disabled by default.
Reviewers: sanjoy, davide, gberry
Subscribers: mehdi_amini, Prazek, llvm-commits
Differential Revision: https://reviews.llvm.org/D40274
llvm-svn: 318772
properlyDominates() shouldn't be used as sort key. It causes different output between stdlibc++ and libc++.
Instead, I introduced RPOT. In most cases, it works for CSE.
llvm-svn: 318743
Summary:
Add the following heuristics for irreducible loop metadata:
- When an irreducible loop header is missing the loop header weight metadata,
give it the minimum weight seen among other headers.
- Annotate indirectbr targets with the loop header weight metadata (as they are
likely to become irreducible loop headers after indirectbr tail duplication.)
These greatly improve the accuracy of the block frequency info of the Python
interpreter loop (eg. from ~3-16x off down to ~40-55% off) and the Python
performance (eg. unpack_sequence from ~50% slower to ~8% faster than GCC) due to
better register allocation under PGO.
Reviewers: davidxl
Reviewed By: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39980
llvm-svn: 318693
Summary:
SROA can fail in rewriting alloca but still rewrite a phi resulting
in dead instruction elimination. The Changed flag was not being set
correctly, resulting in downstream passes using stale analyses.
The included test case will assert during the second BDCE pass as a
result.
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39921
llvm-svn: 318677
Summary:
This change reverts r318575 and changes FindDynamicShadowStart() to
keep the memory range it found mapped PROT_NONE to make sure it is
not reused. We also skip MemoryRangeIsAvailable() check, because it
is (a) unnecessary, and (b) would fail anyway.
Reviewers: pcc, vitalybuka, kcc
Subscribers: srhines, kubamracek, mgorny, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D40203
llvm-svn: 318666
This patch adds a new abstraction layer to VPlan and leverages it to model the planned
instructions that manipulate masks (AND, OR, NOT), introduced during predication.
The new VPValue and VPUser classes model how data flows into, through and out
of a VPlan, forming the vertices of a planned Def-Use graph. The new
VPInstruction class is a generic single-instruction Recipe that models a
planned instruction along with its opcode, operands and users. See
VectorizationPlan.rst for more details.
Differential Revision: https://reviews.llvm.org/D38676
llvm-svn: 318645
In rL316552, we ban intersection of unsigned latch range with signed range check and vice
versa, unless the entire range check iteration space is known positive. It was a correct
functional fix that saved us from dealing with ambiguous values, but it also appeared
to be a very restrictive limitation. In particular, in the following case:
loop:
%iv = phi i32 [ 0, %preheader ], [ %iv.next, %latch]
%iv.offset = add i32 %iv, 10
%rc = icmp slt i32 %iv.offset, %len
br i1 %rc, label %latch, label %deopt
latch:
%iv.next = add i32 %iv, 11
%cond = icmp i32 ult %iv.next, 100
br it %cond, label %loop, label %exit
Here, the unsigned iteration range is `[0, 100)`, and the safe range for range
check is `[-10, %len - 10)`. For unsigned iteration spaces, we use unsigned
min/max functions for range intersection. Given this, we wanted to avoid dealing
with `-10` because it is interpreted as a very big unsigned value. Semantically, range
check's safe range goes through unsigned border, so in fact it is two disjoint
ranges in IV's iteration space. Intersection of such ranges is not trivial, so we prohibited
this case saying that we are not allowed to intersect such ranges.
What semantics of this safe range actually means is that we can start from `-10` and go
up increasing the `%iv` by one until we reach `%len - 10` (for simplicity let's assume that
`%len - 10` is a reasonably big positive value).
In particular, this safe iteration space includes `0, 1, 2, ..., %len - 11`. So if we were able to return
safe iteration space `[0, %len - 10)`, we could safely intersect it with IV's iteration space. All
values in this range are non-negative, so using signed/unsigned min/max for them is unambiguous.
In this patch, we alter the algorithm of safe range calculation so that it returnes a subset of the
original safe space which is represented by one continuous range that does not go through wrap.
In order to reach this, we use modified SCEV substraction function. It can be imagined as a function
that substracts by `1` (or `-1`) as long as the further substraction does not cause a wrap in IV iteration
space. This allows us to perform IRCE in many situations when we deal with IV space and range check
of different types (in terms of signed/unsigned).
We apply this approach for both matching and not matching types of IV iteration space and the
range check. One implication of this is that now IRCE became smarter in detection of empty safe
ranges. For example, in this case:
loop:
%iv = phi i32 [ %begin, %preheader ], [ %iv.next, %latch]
%iv.offset = sub i32 %iv, 10
%rc = icmp ult i32 %iv.offset, %len
br i1 %rc, label %latch, label %deopt
latch:
%iv.next = add i32 %iv, 11
%cond = icmp i32 ult %iv.next, 100
br it %cond, label %loop, label %exit
If `%len` was less than 10 but SCEV failed to trivially prove that `%begin - 10 >u %len- 10`,
we could end up executing entire loop in safe preloop while the main loop was still generated,
but never executed. Now, cutting the ranges so that if both `begin - 10` and `%len - 10` overflow,
we have a trivially empty range of `[0, 0)`. This in some cases prevents us from meaningless optimization.
Differential Revision: https://reviews.llvm.org/D39954
llvm-svn: 318639
As the first test shows, we could transform an llvm intrinsic which never sets errno
into a libcall which could set errno (even though it's marked readnone?), so that's
not ideal.
It's possible that we can also transform a libcall which could set errno to an
intrinsic given the fast-math-flags constraint, but that's deferred to determine
exactly which set of FMF are needed.
Differential Revision: https://reviews.llvm.org/D40150
llvm-svn: 318628
Summary:
With this patch I tried to reduce the complexity of the code sightly, by
removing some indirection. Please let me know what you think.
Reviewers: junbuml, mcrosier, davidxl
Reviewed By: junbuml
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40037
llvm-svn: 318593
We were not doing that for large shadow granularity. Also add more
stack frame layout tests for large shadow granularity.
Differential Revision: https://reviews.llvm.org/D39475
llvm-svn: 318581
Revert the following commits:
r318369 [asan] Fallback to non-ifunc dynamic shadow on android<22.
r318235 [asan] Prevent rematerialization of &__asan_shadow.
r317948 [sanitizer] Remove unnecessary attribute hidden.
r317943 [asan] Use dynamic shadow on 32-bit Android.
MemoryRangeIsAvailable() reads /proc/$PID/maps into an mmap-ed buffer
that may overlap with the address range that we plan to use for the
dynamic shadow mapping. This is causing random startup crashes.
llvm-svn: 318575
Summary: This change fix PR35342 by replacing only the current use with undef in unreachable blocks.
Reviewers: efriedma, mcrosier, igor-laevsky
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40184
llvm-svn: 318551
making it no longer even remotely simple.
The pass will now be more of a "full loop unswitching" pass rather than
anything substantively simpler than any other approach. I plan to rename
it accordingly once the dust settles.
The key ideas of the new loop unswitcher are carried over for
non-trivial unswitching:
1) Fully unswitch a branch or switch instruction from inside of a loop to
outside of it.
2) Update the CFG and IR. This avoids needing to "remember" the
unswitched branches as well as avoiding excessively cloning and
reliance on complex parts of simplify-cfg to cleanup the cfg.
3) Update the analyses (where we can) rather than just blowing them away
or relying on something else updating them.
Sadly, #3 is somewhat compromised here as the dominator tree updates
were too complex for me to want to reason about. I will need to make
another attempt to do this now that we have a nice dynamic update API
for dominators. However, we do adhere to #3 w.r.t. LoopInfo.
This approach also adds an important principls specific to non-trivial
unswitching: not *all* of the loop will be duplicated when unswitching.
This fact allows us to compute the cost in terms of how much *duplicate*
code is inserted rather than just on raw size. Unswitching conditions
which essentialy partition loops will work regardless of the total loop
size.
Some remaining issues that I will be addressing in subsequent commits:
- Handling unstructured control flow.
- Unswitching 'switch' cases instead of just branches.
- Moving to the dynamic update API for dominators.
Some high-level, interesting limitationsV that folks might want to push
on as follow-ups but that I don't have any immediate plans around:
- We could be much more clever about not cloning things that will be
deleted. In fact, we should be able to delete *nothing* and do
a minimal number of clones.
- There are many more interesting selection criteria for which branch to
unswitch that we might want to look at. One that I'm interested in
particularly are a set of conditions which all exit the loop and which
can be merged into a single unswitched test of them.
Differential revision: https://reviews.llvm.org/D34200
llvm-svn: 318549
The logic of replacing of a couple `RANGE_CHECK_LOWER + RANGE_CHECK_UPPER`
into `RANGE_CHECK_BOTH` in fact duplicates the logic of range intersection which
happens when we calculate safe iteration space. Effectively, the result of intersection of
these ranges doesn't differ from the range of merged range check.
We chose to remove duplicating logic in favor of code simplicity.
Differential Revision: https://reviews.llvm.org/D39589
llvm-svn: 318508
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
The requirement is that shadow memory must be aligned to page
boundaries (4k in this case). Use a closed form equation that always
satisfies this requirement.
Differential Revision: https://reviews.llvm.org/D39471
llvm-svn: 318421
// trunc (binop X, C) --> binop (trunc X, C')
// trunc (binop (ext X), Y) --> binop X, (trunc Y)
I'm grouping sub with the other binops because that makes the code simpler
and the transforms are valid:
https://rise4fun.com/Alive/UeF
...so even though we don't expect a sub with constant Op1 or any of the
other opcodes with constant Op0 due to canonicalization rules, we might as
well handle those situations if non-canonical code somehow reaches this
point (it should just make instcombine more efficient in reaching its
end goal).
This should solve the problem that later manifests in the vectorizers in
PR35295:
https://bugs.llvm.org/show_bug.cgi?id=35295
llvm-svn: 318404
Fix a couple places where the minimum alignment/size should be a
function of the shadow granularity:
- alignment of AllGlobals
- the minimum left redzone size on the stack
Added a test to verify that the metadata_array is properly aligned
for shadow scale of 5, to be enabled when we add build support
for testing shadow scale of 5.
Differential Revision: https://reviews.llvm.org/D39470
llvm-svn: 318395
When expanding exit conditions for pre- and postloops, we may end up expanding a
recurrency from the loop to in its loop's preheader. This produces incorrect IR.
This patch ensures that IRCE uses SCEVExpander correctly and only expands code which
is safe to expand in this particular location.
Differentian Revision: https://reviews.llvm.org/D39234
llvm-svn: 318381
Note that one-use and shouldChangeType() are checked ahead of the switch.
Without the narrowing folds, we can produce inferior vector code as shown in PR35299:
https://bugs.llvm.org/show_bug.cgi?id=35299
llvm-svn: 318323
InstCombine salvages debug info for every instruction it erases from its
worklist, but it wasn't doing it during its initial DCE when populating
its worklist. This fixes that.
This should help improve availability of 'this' in optimized debug info
when casts are necessary.
llvm-svn: 318320
Summary:
Added more remarks to SLP pass, in particular "missed" optimization remarks.
Also proposed several tests for new functionality.
Patch by Vladimir Miloserdov!
For reference you may look at: https://reviews.llvm.org/rL302811
Reviewers: anemet, fhahn
Reviewed By: anemet
Subscribers: javed.absar, lattner, petecoup, yakush, llvm-commits
Differential Revision: https://reviews.llvm.org/D38367
llvm-svn: 318307
Summary:
This patch optimizes a binop sandwiched between 2 selects with the same condition. Since we know its only used by the select we can propagate the appropriate input value from the earlier select.
As I'm writing this I realize I may need to avoid doing this for division in case the select was protecting a divide by zero?
Reviewers: spatel, majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39999
llvm-svn: 318267
It crashes building sqlite; see reply on the llvm-commits thread.
> [SLPVectorizer] Failure to beneficially vectorize 'copyable' elements in integer binary ops.
>
> Patch tries to improve vectorization of the following code:
>
> void add1(int * __restrict dst, const int * __restrict src) {
> *dst++ = *src++;
> *dst++ = *src++ + 1;
> *dst++ = *src++ + 2;
> *dst++ = *src++ + 3;
> }
> Allows to vectorize even if the very first operation is not a binary add, but just a load.
>
> Fixed issues related to previous commit.
>
> Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev
>
> Reviewed By: ABataev, RKSimon
>
> Subscribers: llvm-commits, RKSimon
>
> Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 318239
Simplifying a loop latch changes the IR and we need to make sure the pass manager knows to invalidate analysis passes if that happened.
PR35210 discovered a case where we failed to invalidate the post dominator tree after this simplification because we no changes other than simplifying the loop latch.
Fixes PR35210.
Differential Revision: https://reviews.llvm.org/D40035
llvm-svn: 318237
Summary:
In the mode when ASan shadow base is computed as the address of an
external global (__asan_shadow, currently on android/arm32 only),
regalloc prefers to rematerialize this value to save register spills.
Even in -Os. On arm32 it is rather expensive (2 loads + 1 constant
pool entry).
This changes adds an inline asm in the function prologue to suppress
this behavior. It reduces AsanTest binary size by 7%.
Reviewers: pcc, vitalybuka
Subscribers: aemerson, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40048
llvm-svn: 318235
Summary:
Instcombine (and probably other passes) sometimes want to change the
type of an alloca. To do this, they generally create a new alloca with
the desired type, create a bitcast to make the new pointer type match
the old pointer type, replace all uses with the cast, and then simplify
the casts. We already knew how to salvage dbg.value instructions when
removing casts, but we can extend it to cover dbg.addr and dbg.declare.
Fixes a debug info quality issue uncovered in Chromium in
http://crbug.com/784609
Reviewers: aprantl, vsk
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40042
llvm-svn: 318203
Clang implements the -finstrument-functions flag inherited from GCC, which
inserts calls to __cyg_profile_func_{enter,exit} on function entry and exit.
This is useful for getting a trace of how the functions in a program are
executed. Normally, the calls remain even if a function is inlined into another
function, but it is useful to be able to turn this off for users who are
interested in a lower-level trace, i.e. one that reflects what functions are
called post-inlining. (We use this to generate link order files for Chromium.)
LLVM already has a pass for inserting similar instrumentation calls to
mcount(), which it does after inlining. This patch renames and extends that
pass to handle calls both to mcount and the cygprofile functions, before and/or
after inlining as controlled by function attributes.
Differential Revision: https://reviews.llvm.org/D39287
llvm-svn: 318195
Patch tries to improve vectorization of the following code:
void add1(int * __restrict dst, const int * __restrict src) {
*dst++ = *src++;
*dst++ = *src++ + 1;
*dst++ = *src++ + 2;
*dst++ = *src++ + 3;
}
Allows to vectorize even if the very first operation is not a binary add, but just a load.
Fixed issues related to previous commit.
Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev
Reviewed By: ABataev, RKSimon
Subscribers: llvm-commits, RKSimon
Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 318193
This patch is part of D38676.
The patch introduces two new Recipes to handle instructions whose vectorization
involves masking. These Recipes take VPlan-level masks in D38676, but still rely
on ILV's existing createEdgeMask(), createBlockInMask() in this patch.
VPBlendRecipe handles intra-loop phi nodes, which are vectorized as a sequence
of SELECTs. Its execute() code is refactored out of ILV::widenPHIInstruction(),
which now handles only loop-header phi nodes.
VPWidenMemoryInstructionRecipe handles load/store which are to be widened
(but are not part of an Interleave Group). In this patch it simply calls
ILV::vectorizeMemoryInstruction on execute().
Differential Revision: https://reviews.llvm.org/D39068
llvm-svn: 318149
Registers it and everything, updates all the references, etc.
Next patch will add support to Clang's `-fexperimental-new-pass-manager`
path to actually enable BoundsChecking correctly.
Differential Revision: https://reviews.llvm.org/D39084
llvm-svn: 318128
a legacy and new PM pass.
This essentially moves the class state to parameters and re-shuffles the
code to make that reasonable. It also does some minor cleanups along the
way and leaves some comments.
Differential Revision: https://reviews.llvm.org/D39081
llvm-svn: 318124
Summary:
If a compare instruction is same or inverse of the compare in the
branch of the loop latch, then return a constant evolution node.
This shall facilitate computations of loop exit counts in cases
where compare appears in the evolution chain of induction variables.
Will fix PR 34538
Reviewers: sanjoy, hfinkel, junryoungju
Reviewed By: sanjoy, junryoungju
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38494
llvm-svn: 318050
In more recent Linux kernels (including those with 47 bit VMAs) the layout of
virtual memory for powerpc64 changed causing the memory sanitizer to not
work properly. This patch adjusts a bit mask in the memory sanitizer to work
on the newer kernels while continuing to work on the older ones as well.
This is the non-runtime part of the patch and finishes it. ref: r317802
Tested on several 4.x and 3.x kernel releases.
llvm-svn: 318045
Summary:
This patch extends the partial inliner to support inlining parts of
vararg functions, if the vararg handling is done in the outlined part.
It adds a `ForwardVarArgsTo` argument to InlineFunction. If it is
non-null, all varargs passed to the inlined function will be added to
all calls to `ForwardVarArgsTo`.
The partial inliner takes care to only pass `ForwardVarArgsTo` if the
varargs handing is done in the outlined function. It checks that vastart
is not part of the function to be inlined.
`test/Transforms/CodeExtractor/PartialInlineNoInline.ll` (already part
of the repo) checks we do not do partial inlining if vastart is used in
a basic block that will be inlined.
Reviewers: davide, davidxl, grosser
Reviewed By: davide, davidxl, grosser
Subscribers: gyiu, grosser, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D39607
llvm-svn: 318028
Summary:
This patch adds an early out to visitICmpInst if we are looking at a compare as part of an integer absolute value idiom. Similar is already done for min/max.
In the particular case I observed in a benchmark we had an absolute value of a load from an indexed global. We simplified the compare using foldCmpLoadFromIndexedGlobal into a magic bit vector, a shift, and an and. But the load result was still used for the select and the negate part of the absolute valute idiom. So we overcomplicated the code and lost the ability to recognize it as an absolute value.
I've chosen a simpler case for the test here.
Reviewers: spatel, davide, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39766
llvm-svn: 317994
Summary:
The following kernel change has moved ET_DYN base to 0x4000000 on arm32:
https://marc.info/?l=linux-kernel&m=149825162606848&w=2
Switch to dynamic shadow base to avoid such conflicts in the future.
Reserve shadow memory in an ifunc resolver, but don't use it in the instrumentation
until PR35221 is fixed. This will eventually let use save one load per function.
Reviewers: kcc
Subscribers: aemerson, srhines, kubamracek, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D39393
llvm-svn: 317943
Summary:
The specification of the @llvm.memcpy.element.unordered.atomic intrinsic requires
that the pointer arguments have alignments of at least the element size. The existing
IRBuilder interface to create a call to this intrinsic does not allow for providing
the alignment of these pointer args. Having an interface that makes it easy to
construct invalid intrinsic calls doesn't seem sensible, so this patch simply
adds the requirement that one provide the argument alignments when using IRBuilder
to create atomic memcpy calls.
llvm-svn: 317918
Summary:
This adds logic to CVP to remove some overflow checks. It uses LVI to remove
operations with at least one constant. Specifically, this can remove many
overflow intrinsics immediately following an overflow check in the source code,
such as:
if (x < INT_MAX)
... x + 1 ...
Patch by Joel Galenson!
Reviewers: sanjoy, regehr
Reviewed By: sanjoy
Subscribers: fhahn, pirama, srhines, llvm-commits
Differential Revision: https://reviews.llvm.org/D39483
llvm-svn: 317911
Summary:
This wrapper checks if there is at least one non-zero weight before
setting the metadata.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39872
llvm-svn: 317845
When the Constant Hoisting pass moves expensive constants into a
common block, it would assign a debug location equal to the last use
of that constant. While this is certainly intuitive, it places the
constant in an out-of-order location, according to the debug location
information. This produces out-of-order stepping when debugging
programs affected by this pass.
This patch creates in-order stepping behavior by merging the debug
locations for hoisted constants, and the new insertion point.
Patch by Matthew Voss!
Differential Revision: https://reviews.llvm.org/D38088
llvm-svn: 317827
Summary:
The analysis of the store sequence goes in straight order - from the
first store to the last. Bu the best opportunity for vectorization will
happen if we're going to use reverse order - from last store to the
first. It may be best because usually users have some initialization
part + further processing and this first initialization may confuse
SLP vectorizer.
Reviewers: RKSimon, hfinkel, mkuper, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39606
llvm-svn: 317821
The toxic stew of created values named 'tmp' and tests that already have
values named 'tmp' and CHECK lines looking for values named 'tmp' causes
bad things to happen in our test line auto-generation scripts because it
wants to use 'TMP' as a prefix for unnamed values. Use less 'tmp' to
avoid that.
llvm-svn: 317818
We must patch all existing incoming values of Phi node,
otherwise it is possible that we can see poison
where program does not expect to see it.
This is the similar what GVN does.
The added test test/Transforms/GVN/PRE/pre-jt-add.ll shows an
example of wrong optimization done by jump threading due to
GVN PRE did not patch existing incoming value.
Reviewers: mkazantsev, wmi, dberlin, davide
Reviewed By: dberlin
Subscribers: efriedma, llvm-commits
Differential Revision: https://reviews.llvm.org/D39637
llvm-svn: 317768
This patch implements Chandler's idea [0] for supporting languages that
require support for infinite loops with side effects, such as Rust, providing
part of a solution to bug 965 [1].
Specifically, it adds an `llvm.sideeffect()` intrinsic, which has no actual
effect, but which appears to optimization passes to have obscure side effects,
such that they don't optimize away loops containing it. It also teaches
several optimization passes to ignore this intrinsic, so that it doesn't
significantly impact optimization in most cases.
As discussed on llvm-dev [2], this patch is the first of two major parts.
The second part, to change LLVM's semantics to have defined behavior
on infinite loops by default, with a function attribute for opting into
potential-undefined-behavior, will be implemented and posted for review in
a separate patch.
[0] http://lists.llvm.org/pipermail/llvm-dev/2015-July/088103.html
[1] https://bugs.llvm.org/show_bug.cgi?id=965
[2] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118632.html
Differential Revision: https://reviews.llvm.org/D38336
llvm-svn: 317729
Summary:
In ThinLTO compilation, we exit populateModulePassManager early and
were not adding PM extension passes meant to run at the end of the
pipeline. This includes sanitizer passes. Add these passes before
the early exit.
A test will be added to projects/compiler-rt.
Reviewers: pcc
Subscribers: mehdi_amini, inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D39565
llvm-svn: 317714
Patch tries to improve vectorization of the following code:
void add1(int * __restrict dst, const int * __restrict src) {
*dst++ = *src++;
*dst++ = *src++ + 1;
*dst++ = *src++ + 2;
*dst++ = *src++ + 3;
}
Allows to vectorize even if the very first operation is not a binary add, but just a load.
Fixed PR34619 and other issues related to previous commit.
Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev
Reviewed By: ABataev, RKSimon
Subscribers: llvm-commits, RKSimon
Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 317618
The hexagon test should be fixed now.
Original commit message:
This pulls shifts through a select+binop with a constant where the select conditionally executes the binop. We already do this for just the binop, but not with the select.
This can allow us to get the select closer to other selects to enable removing one.
Differential Revision: https://reviews.llvm.org/D39222
llvm-svn: 317600
Blockaddresses refer to the function itself, therefore replacing them
would cause an assertion in doRAUW.
Fixes https://bugs.llvm.org/show_bug.cgi?id=35201
This was found when trying CFI on a proprietary kernel by Dmitry Mikulin.
Differential Revision: https://reviews.llvm.org/D39695
llvm-svn: 317527
This broke the CodeGen/Hexagon/loop-idiom/pmpy-mod.ll test on a bunch of buildbots.
> This pulls shifts through a select+binop with a constant where the select conditionally executes the binop. We already do this for just the binop, but not with the select.
>
> This can allow us to get the select closer to other selects to enable removing one.
>
> Differential Revision: https://reviews.llvm.org/D39222
>
> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317510 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-svn: 317518
This pulls shifts through a select+binop with a constant where the select conditionally executes the binop. We already do this for just the binop, but not with the select.
This can allow us to get the select closer to other selects to enable removing one.
Differential Revision: https://reviews.llvm.org/D39222
llvm-svn: 317510
Summary: When computing the SUM for indirect call promotion, if the callsite is already promoted in the profile, it will be promoted before ICP. In the current implementation, ICP only sees remaining counts in SUM. This may cause extra indirect call targets being promoted. This patch updates the SUM to include the counts already promoted earlier. This way we do not end up promoting too many indirect call targets.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D38763
llvm-svn: 317502
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/107104.html
and again more recently:
http://lists.llvm.org/pipermail/llvm-dev/2017-October/118118.html
...this is a step in cleaning up our fast-math-flags implementation in IR to better match
the capabilities of both clang's user-visible flags and the backend's flags for SDNode.
As proposed in the above threads, we're replacing the 'UnsafeAlgebra' bit (which had the
'umbrella' meaning that all flags are set) with a new bit that only applies to algebraic
reassociation - 'AllowReassoc'.
We're also adding a bit to allow approximations for library functions called 'ApproxFunc'
(this was initially proposed as 'libm' or similar).
...and we're out of bits. 7 bits ought to be enough for anyone, right? :) FWIW, I did
look at getting this out of SubclassOptionalData via SubclassData (spacious 16-bits),
but that's apparently already used for other purposes. Also, I don't think we can just
add a field to FPMathOperator because Operator is not intended to be instantiated.
We'll defer movement of FMF to another day.
We keep the 'fast' keyword. I thought about removing that, but seeing IR like this:
%f.fast = fadd reassoc nnan ninf nsz arcp contract afn float %op1, %op2
...made me think we want to keep the shortcut synonym.
Finally, this change is binary incompatible with existing IR as seen in the
compatibility tests. This statement:
"Newer releases can ignore features from older releases, but they cannot miscompile
them. For example, if nsw is ever replaced with something else, dropping it would be
a valid way to upgrade the IR."
( http://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility )
...provides the flexibility we want to make this change without requiring a new IR
version. Ie, we're not loosening the FP strictness of existing IR. At worst, we will
fail to optimize some previously 'fast' code because it's no longer recognized as
'fast'. This should get fixed as we audit/squash all of the uses of 'isFast()'.
Note: an inter-dependent clang commit to use the new API name should closely follow
commit.
Differential Revision: https://reviews.llvm.org/D39304
llvm-svn: 317488
Now that we have a way to mark GlobalValues as local we can use the symbol
resolutions that the linker plugin provides as part of lto/thinlto link
step to refine the compilers view on what symbols will end up being local.
Originally commited as r317374, but reverted in r317395 to update some missed
tests.
Differential Revision: https://reviews.llvm.org/D35702
llvm-svn: 317408
This preserves the debug info for the cast operation in the original location.
rdar://problem/33460652
Reapplied r317340 with the test moved into an ARM-specific directory.
llvm-svn: 317375
Now that we have a way to mark GlobalValues as local we can use the symbol
resolutions that the linker plugin provides as part of lto/thinlto link
step to refine the compilers view on what symbols will end up being local.
Differential Revision: https://reviews.llvm.org/D35702
llvm-svn: 317374
Merging conditional stores tries to check to see if the code is if convertible after the store is moved. But the store hasn't been moved yet so its being counted against the threshold.
The patch adds 1 to the threshold comparison to make sure we don't count the store. I've adjusted a test to use a lower threshold to ensure we still do that conversion with the lower threshold.
Differential Revision: https://reviews.llvm.org/D39570
llvm-svn: 317368
This recommit r317351 after fixing a buildbot failure.
Original commit message:
Summary:
This change add a pass which tries to split a call-site to pass
more constrained arguments if its argument is predicated in the control flow
so that we can expose better context to the later passes (e.g, inliner, jump
threading, or IPA-CP based function cloning, etc.).
As of now we support two cases :
1) If a call site is dominated by an OR condition and if any of its arguments
are predicated on this OR condition, try to split the condition with more
constrained arguments. For example, in the code below, we try to split the
call site since we can predicate the argument (ptr) based on the OR condition.
Split from :
if (!ptr || c)
callee(ptr);
to :
if (!ptr)
callee(null ptr) // set the known constant value
else if (c)
callee(nonnull ptr) // set non-null attribute in the argument
2) We can also split a call-site based on constant incoming values of a PHI
For example,
from :
BB0:
%c = icmp eq i32 %i1, %i2
br i1 %c, label %BB2, label %BB1
BB1:
br label %BB2
BB2:
%p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ]
call void @bar(i32 %p)
to
BB0:
%c = icmp eq i32 %i1, %i2
br i1 %c, label %BB2-split0, label %BB1
BB1:
br label %BB2-split1
BB2-split0:
call void @bar(i32 0)
br label %BB2
BB2-split1:
call void @bar(i32 1)
br label %BB2
BB2:
%p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ]
llvm-svn: 317362
Summary:
This change add a pass which tries to split a call-site to pass
more constrained arguments if its argument is predicated in the control flow
so that we can expose better context to the later passes (e.g, inliner, jump
threading, or IPA-CP based function cloning, etc.).
As of now we support two cases :
1) If a call site is dominated by an OR condition and if any of its arguments
are predicated on this OR condition, try to split the condition with more
constrained arguments. For example, in the code below, we try to split the
call site since we can predicate the argument (ptr) based on the OR condition.
Split from :
if (!ptr || c)
callee(ptr);
to :
if (!ptr)
callee(null ptr) // set the known constant value
else if (c)
callee(nonnull ptr) // set non-null attribute in the argument
2) We can also split a call-site based on constant incoming values of a PHI
For example,
from :
BB0:
%c = icmp eq i32 %i1, %i2
br i1 %c, label %BB2, label %BB1
BB1:
br label %BB2
BB2:
%p = phi i32 [ 0, %BB0 ], [ 1, %BB1 ]
call void @bar(i32 %p)
to
BB0:
%c = icmp eq i32 %i1, %i2
br i1 %c, label %BB2-split0, label %BB1
BB1:
br label %BB2-split1
BB2-split0:
call void @bar(i32 0)
br label %BB2
BB2-split1:
call void @bar(i32 1)
br label %BB2
BB2:
%p = phi i32 [ 0, %BB2-split0 ], [ 1, %BB2-split1 ]
Reviewers: davidxl, huntergr, chandlerc, mcrosier, eraman, davide
Reviewed By: davidxl
Subscribers: sdesmalen, ashutosh.nema, fhahn, mssimpso, aemerson, mgorny, mehdi_amini, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D39137
llvm-svn: 317351
Summary:
The current LICM allows sinking an instruction only when it is exposed to exit
blocks through a trivially replacable PHI of which all incoming values are the
same instruction. This change enhance LICM to sink a sinkable instruction
through non-trivially replacable PHIs by spliting predecessors of loop
exits.
Reviewers: hfinkel, majnemer, davidxl, bmakam, mcrosier, danielcdh, efriedma, jtony
Reviewed By: efriedma
Subscribers: nemanjai, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D37163
llvm-svn: 317335
Summary:
Refactored the code to separate out common functions that are being
reused.
This is to reduce the changes for changes coming up wrt loop
predication with reverse loops.
This refactoring is what we have in our downstream code.
llvm-svn: 317324
Summary:
Also added a reserve() method to MapVector since we want to use that from
ADCE.
DenseMap does not provide deterministic iteration order so with that
we will handle the members of BlockInfo in random order, eventually
leading to random order of the blocks in the predecessor lists.
Without this change, I get the same predecessor order in about 90% of the
time when I compile a certain reproducer and in 10% I get a different one.
No idea how to make a proper test case for this.
Reviewers: kuhar, david2050
Reviewed By: kuhar
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39593
llvm-svn: 317323
Summary:
InlineFunction can fail, for example when trying to inline vararg
fuctions. In those cases, we do not want to bump partial inlining
counters or set AnyInlined to true, because this could leave an unused
function hanging around.
Reviewers: davidxl, davide, gyiu
Reviewed By: davide
Subscribers: llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D39581
llvm-svn: 317314
Summary:
Currently the block frequency analysis is an approximation for irreducible
loops.
The new irreducible loop metadata is used to annotate the irreducible loop
headers with their header weights based on the PGO profile (currently this is
approximated to be evenly weighted) and to help improve the accuracy of the
block frequency analysis for irreducible loops.
This patch is a basic support for this.
Reviewers: davidxl
Reviewed By: davidxl
Subscribers: mehdi_amini, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D39028
llvm-svn: 317278
Summary:
This patch allows us to predicate range checks that have a type narrower than
the latch check type. We leverage SCEV analysis to identify a truncate for the
latchLimit and latchStart.
There is also safety checks in place which requires the start and limit to be
known at compile time. We require this to make sure that the SCEV truncate expr
for the IV corresponding to the latch does not cause us to lose information
about the IV range.
Added tests show the loop predication over range checks that are of various
types and are narrower than the latch type.
This enhancement has been in our downstream tree for a while.
Reviewers: apilipenko, sanjoy, mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39500
llvm-svn: 317269
The original change was reverted in rL317217 because of the failure in
the RS4GC testcase. I couldn't reproduce the failure on my local machine
(macbook) but could reproduce it on a linux box.
The failure was around removing the uses of invariant.start. The fix
here is to just RAUW undef (which was the first implementation in D39388).
This is perfectly valid IR as discussed in the review.
llvm-svn: 317225
Summary:
Invariant.start on memory locations has the property that the memory
location is unchanging. However, this is not true in the face of
rewriting statepoints for GC.
Teach RS4GC about removing invariant.start so that optimizations after
RS4GC does not incorrect sink a load from the memory location past a
statepoint.
Added test showcasing the issue.
Reviewers: reames, apilipenko, dneilson
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39388
llvm-svn: 317215
undefined reference to `llvm::TargetPassConfig::ID' on
clang-ppc64le-linux-multistage
This reverts commit eea333c33fa73ad225ef28607795984829f65688.
llvm-svn: 317213
Summary:
This is mostly a noop (most of the test diffs are renamed blocks).
There are a few temporary register renames (eax<->ecx) and a few blocks are
shuffled around.
See the discussion in PR33325 for more details.
Reviewers: spatel
Subscribers: mgorny
Differential Revision: https://reviews.llvm.org/D39456
llvm-svn: 317211
Summary:
SpeculativelyExecuteBB can flatten the CFG by doing
speculative execution followed by a select instruction.
When the speculatively executed BB contained dbg intrinsics
the result could be a little bit weird, since those dbg
intrinsics were inserted before the select in the flattened
CFG. So when single stepping in the debugger, printing the
value of the variable referenced in the dbg intrinsic, it
could happen that it looked like the variable had values
that never actually were assigned to the variable.
This patch simply discards all dbg intrinsics that were found
in the speculatively executed BB.
Reviewers: aprantl, chandlerc, craig.topper
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39494
llvm-svn: 317198
Summary: In the compile phase of SamplePGO+ThinLTO, ICP is not invoked. Instead, indirect call targets will be included as function metadata for ThinIndex to buidl the call graph. This should not only include functions defined in other modules, but also functions defined in the same module, otherwise ThinIndex may find the callee dead and eliminate it, while ICP in backend will revive the symbol, which leads to undefined symbol.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D39480
llvm-svn: 317118
This is necessary because DCE is applied to full LTO modules. Without
this change, a reference from a dead ThinLTO global to a dead full
LTO global will result in an undefined reference at link time.
This problem is only observable when --gc-sections is disabled, or
when targeting COFF, as the COFF port of lld requires all symbols to
have a definition even if all references are dead (this is consistent
with link.exe).
This change also adds an EliminateAvailableExternally pass at -O0. This
is necessary to handle the situation on Windows where a non-prevailing
copy of a linkonce_odr function has an SEH filter function; any
such filters must be DCE'd because they will contain a call to the
llvm.localrecover intrinsic, passing as an argument the address of the
function that the filter belongs to, and llvm.localrecover requires
this function to be defined locally.
Fixes PR35142.
Differential Revision: https://reviews.llvm.org/D39484
llvm-svn: 317108
This patch reverts rL311205 that was initially a wrong fix. The real problem
was in intersection of signed and unsigned ranges (see rL316552), and the
patch being reverted masked the problem instead of fixing it.
By now, the test against which rL311205 was made works OK even without this
code. This revert patch also contains a test case that demonstrates incorrect
behavior caused by rL311205: it is caused by incorrect choise of signed max
instead of unsigned.
llvm-svn: 317088
Summary:
By replacing branches to CommonExitBlock, we remove the node from
CommonExitBlock's predecessors, invalidating the iterator. The problem
is exposed when the common exit block has multiple predecessors and
needs to sink lifetime info. The modification in the test case trigger
the issue.
Reviewers: davidxl, davide, wmi
Reviewed By: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39112
llvm-svn: 317084
This formulation might be slightly slower since I eagerly compute the cheap replacements. If anyone sees this having a compile time impact, let me know and I'll use lazy population instead.
llvm-svn: 317048
Currently the selects are created with the names of their inputs concatenated together. It's possible to get cases that chain these selects together resulting in long names due to multiple levels of concatenation. Our internal branch of llvm managed to generate names over 100000 characters in length on a particular test due to an extreme compounding of the names.
This patch changes the name to a generic name that is not dependent on its inputs.
Differential Revision: https://reviews.llvm.org/D39440
llvm-svn: 317024
If a select instruction tests the returned flag of a cmpxchg instruction and
selects between the returned value of the cmpxchg instruction and its compare
operand, the result of the select will always be equal to its false value.
Differential Revision: https://reviews.llvm.org/D39383
llvm-svn: 316994
The optimisation remarks for loop unrolling with an unrolled remainder looks something like:
test.c:7:18: remark: completely unrolled loop with 3 iterations [-Rpass=loop-unroll]
C[i] += A[i*N+j];
^
test.c:6:9: remark: unrolled loop by a factor of 4 with run-time trip count [-Rpass=loop-unroll]
for(int j = 0; j < N; j++)
^
This removes the first of the two messages.
Differential revision: https://reviews.llvm.org/D38725
llvm-svn: 316986
Rename `Offset`, `Scale`, `Length` into `Begin`, `Step`, `End` respectively
to make naming of similar entities for Ranges and Range Checks more
consistent.
Differential Revision: https://reviews.llvm.org/D39414
llvm-svn: 316979
As noted in the nice block comment, the previous code didn't actually handle multi-entry loops correctly, it just assumed SCEV didn't analyze such loops. Given SCEV has comments to the contrary, that seems a bit suspect. More importantly, the pass actually requires loopsimplify form which ensures a loop-preheader is available. Remove the excessive generaility and shorten the code greatly.
Note that we do successfully analyze many multi-entry loops, but we do so by converting them to single entry loops. See the added test case.
llvm-svn: 316976
This patch fixes the miscompile that happens when PRE hoists loads across guards and
other instructions that don't always pass control flow to their successors. PRE is now prohibited
to hoist across such instructions because there is no guarantee that the load standing after such
instruction is still valid before such instruction. For example, a load from under a guard may be
invalid before the guard in the following case:
int array[LEN];
...
guard(0 <= index && index < LEN);
use(array[index]);
Differential Revision: https://reviews.llvm.org/D37460
llvm-svn: 316975
Previously, the code returned early from the *function* when it couldn't find a free expansion, it should be returning from the *transform*. I don't have a test case, noticed this via inspection.
As a follow up, I'm going to revisit the logic in the extract function. I think that essentially the whole helper routine can be replaced with SCEVExpander, but I wanted to do that in a series of separate commits.
llvm-svn: 316974
Issue found by llvm-isel-fuzzer on OSS fuzz, https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=3725
If anyone actually cares about > 64 bit arithmetic, there's a lot more to do in this area. There's a bunch of obviously wrong code in the same function. I don't have the time to fix all of them and am just using this to understand what the workflow for fixing fuzzer cases might look like.
llvm-svn: 316967
InferAddressSpaces assumes the pointee type of addrspacecast
is the same as the operand, which is not always true and causes
invalid IR.
This bug cause build failure in HCC.
This patch fixes that.
Differential Revision: https://reviews.llvm.org/D39432
llvm-svn: 316957
It's not guaranteed. There's a bug open to sort them in predecessor
order, but it won't happen anytime soon. In the meanwhile, passes
will have to do an O(#preds) scan. Such is life.
llvm-svn: 316953
Summary:
For reference, see: http://lists.llvm.org/pipermail/llvm-dev/2017-August/116589.html
This patch fleshes out the instruction class hierarchy with respect to atomic and
non-atomic memory intrinsics. With this change, the relevant part of the class
hierarchy becomes:
IntrinsicInst
-> MemIntrinsicBase (methods-only class)
-> MemIntrinsic (non-atomic intrinsics)
-> MemSetInst
-> MemTransferInst
-> MemCpyInst
-> MemMoveInst
-> AtomicMemIntrinsic (atomic intrinsics)
-> AtomicMemSetInst
-> AtomicMemTransferInst
-> AtomicMemCpyInst
-> AtomicMemMoveInst
-> AnyMemIntrinsic (both atomicities)
-> AnyMemSetInst
-> AnyMemTransferInst
-> AnyMemCpyInst
-> AnyMemMoveInst
This involves some class renaming:
ElementUnorderedAtomicMemCpyInst -> AtomicMemCpyInst
ElementUnorderedAtomicMemMoveInst -> AtomicMemMoveInst
ElementUnorderedAtomicMemSetInst -> AtomicMemSetInst
A script for doing this renaming in downstream trees is included below.
An example of where the Any* classes should be used in LLVM is when reasoning
about the effects of an instruction (ex: aliasing).
---
Script for renaming AtomicMem* classes:
PREFIXES="[<,([:space:]]"
CLASSES="MemIntrinsic|MemTransferInst|MemSetInst|MemMoveInst|MemCpyInst"
SUFFIXES="[;)>,[:space:]]"
REGEX="(${PREFIXES})ElementUnorderedAtomic(${CLASSES})(${SUFFIXES})"
REGEX2="visitElementUnorderedAtomic(${CLASSES})"
FILES=$( grep -E "(${REGEX}|${REGEX2})" -r . | tr ':' ' ' | awk '{print $1}' | sort | uniq )
SED_SCRIPT="s~${REGEX}~\1Atomic\2\3~g"
SED_SCRIPT2="s~${REGEX2}~visitAtomic\1~g"
for f in $FILES; do
echo "Processing: $f"
sed -i ".bak" -E "${SED_SCRIPT};${SED_SCRIPT2};${EA_SED_SCRIPT};${EA_SED_SCRIPT2}" $f
done
Reviewers: sanjoy, deadalnix, apilipenko, anna, skatkov, mkazantsev
Reviewed By: sanjoy
Subscribers: hfinkel, jholewinski, arsenm, sdardis, nhaehnle, JDevlieghere, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38419
llvm-svn: 316950
- Targets that want to support memcmp expansions now return the list of
supported load sizes.
- Expansion codegen does not assume that all power-of-two load sizes
smaller than the max load size are valid. For examples, this is not the
case for x86(32bit)+sse2.
Fixes PR34887.
llvm-svn: 316905
This version of the patch includes a fix addressing a stage2 LTO buildbot
failure and addressed some additional nits.
Original commit message:
This updates the SCCP solver to use of the ValueElement lattice for
parameters, which provides integer range information. The range
information is used to remove unneeded icmp instructions.
For the following function, f() can be optimized to ret i32 2 with
this change
source_filename = "sccp.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @main() local_unnamed_addr #0 {
entry:
%call = tail call fastcc i32 @f(i32 1)
%call1 = tail call fastcc i32 @f(i32 47)
%add3 = add nsw i32 %call, %call1
ret i32 %add3
}
; Function Attrs: noinline norecurse nounwind readnone uwtable
define internal fastcc i32 @f(i32 %x) unnamed_addr #1 {
entry:
%c1 = icmp sle i32 %x, 100
%cmp = icmp sgt i32 %x, 300
%. = select i1 %cmp, i32 1, i32 2
ret i32 %.
}
attributes #1 = { noinline }
Reviewers: davide, sanjoy, efriedma, dberlin
Reviewed By: davide, dberlin
Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D36656
llvm-svn: 316891
This version of the patch includes a fix addressing a stage2 LTO buildbot
failure and addressed some additional nits.
Original commit message:
This updates the SCCP solver to use of the ValueElement lattice for
parameters, which provides integer range information. The range
information is used to remove unneeded icmp instructions.
For the following function, f() can be optimized to ret i32 2 with
this change
source_filename = "sccp.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @main() local_unnamed_addr #0 {
entry:
%call = tail call fastcc i32 @f(i32 1)
%call1 = tail call fastcc i32 @f(i32 47)
%add3 = add nsw i32 %call, %call1
ret i32 %add3
}
; Function Attrs: noinline norecurse nounwind readnone uwtable
define internal fastcc i32 @f(i32 %x) unnamed_addr #1 {
entry:
%c1 = icmp sle i32 %x, 100
%cmp = icmp sgt i32 %x, 300
%. = select i1 %cmp, i32 1, i32 2
ret i32 %.
}
attributes #1 = { noinline }
Reviewers: davide, sanjoy, efriedma, dberlin
Reviewed By: davide, dberlin
Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D36656
llvm-svn: 316887
This is no-functional-change-intended.
This is repackaging the functionality of D30333 (defer switch-to-lookup-tables) and
D35411 (defer folding unconditional branches) with pass parameters rather than a named
"latesimplifycfg" pass. Now that we have individual options to control the functionality,
we could decouple when these fire (but that's an independent patch if desired).
The next planned step would be to add another option bit to disable the sinking transform
mentioned in D38566. This should also make it clear that the new pass manager needs to
be updated to limit simplifycfg in the same way as the old pass manager.
Differential Revision: https://reviews.llvm.org/D38631
llvm-svn: 316835
Summary:
We shouldn't do this transformation if the function is marked nobuitlin.
We were only checking that the return type is floating point, we really should be checking the argument types and argument count as well. This can be accomplished by using the other version of getLibFunc that takes the Function and not just the name.
We should also be checking TLI::has since sqrtf is a macro on Windows.
Fixes PR32559.
Reviewers: hfinkel, spatel, davide, efriedma
Reviewed By: davide, efriedma
Subscribers: efriedma, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D39381
llvm-svn: 316819
This is a follow up change for D37569.
Currently the transformation is limited to the case when:
* The loop has a single latch with the condition of the form: ++i <pred> latchLimit, where <pred> is u<, u<=, s<, or s<=.
* The step of the IV used in the latch condition is 1.
* The IV of the latch condition is the same as the post increment IV of the guard condition.
* The guard condition is of the form i u< guardLimit.
This patch enables the transform in the case when the latch is
latchStart + i <pred> latchLimit, where <pred> is u<, u<=, s<, or s<=.
And the guard is
guardStart + i u< guardLimit
Reviewed By: anna
Differential Revision: https://reviews.llvm.org/D39097
llvm-svn: 316768
Summary: There are certain requirements for debug location of debug intrinsics, e.g. the scope of the DILocalVariable should be the same as the scope of its debug location. As a result, we should not add discriminator encoding for debug intrinsics.
Reviewers: dblaikie, aprantl
Reviewed By: aprantl
Subscribers: JDevlieghere, aprantl, bjope, sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D39343
llvm-svn: 316703
When going to explain this to someone else, I got tripped up by the complicated meaning of IsKnownNonEscapingObject in load-store promotion. Extract a helper routine and clarify naming/scopes to make this a bit more obvious.
llvm-svn: 316699
Summary:
We no longer add vectors of pointers as candidates for
load/store vectorization. It does not seem to work anyway,
but without this patch we can end up in asserts when trying
to create casts between an integer type and the pointer of
vectors type.
The test case I've added used to assert like this when trying to
cast between i64 and <2 x i16*>:
opt: ../lib/IR/Instructions.cpp:2565: Assertion `castIsValid(op, S, Ty) && "Invalid cast!"' failed.
#0 PrintStackTraceSignalHandler(void*)
#1 SignalHandler(int)
#2 __restore_rt
#3 __GI_raise
#4 __GI_abort
#5 __GI___assert_fail
#6 llvm::CastInst::Create(llvm::Instruction::CastOps, llvm::Value*, llvm::Type*, llvm::Twine const&, llvm::Instruction*)
#7 llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>::CreateBitOrPointerCast(llvm::Value*, llvm::Type*, llvm::Twine const&)
#8 Vectorizer::vectorizeStoreChain(llvm::ArrayRef<llvm::Instruction*>, llvm::SmallPtrSet<llvm::Instruction*, 16u>*)
Reviewers: arsenm
Reviewed By: arsenm
Subscribers: nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D39296
llvm-svn: 316665
Summary:
The code comments indicate that no effort has been spent on
handling load/stores when the size isn't a multiple of the
byte size correctly. However, the code only avoided types
smaller than 8 bits. So for example a load of an i28 could
still be considered as a candidate for vectorization.
This patch adjusts the code to behave according to the code
comment.
The test case used to hit the following assert when
trying to use "cast" an i32 to i28 using CreateBitOrPointerCast:
opt: ../lib/IR/Instructions.cpp:2565: Assertion `castIsValid(op, S, Ty) && "Invalid cast!"' failed.
#0 PrintStackTraceSignalHandler(void*)
#1 SignalHandler(int)
#2 __restore_rt
#3 __GI_raise
#4 __GI_abort
#5 __GI___assert_fail
#6 llvm::CastInst::Create(llvm::Instruction::CastOps, llvm::Value*, llvm::Type*, llvm::Twine const&, llvm::Instruction*)
#7 llvm::IRBuilder<llvm::ConstantFolder, llvm::IRBuilderDefaultInserter>::CreateBitOrPointerCast(llvm::Value*, llvm::Type*, llvm::Twine const&)
#8 (anonymous namespace)::Vectorizer::vectorizeLoadChain(llvm::ArrayRef<llvm::Instruction*>, llvm::SmallPtrSet<llvm::Instruction*, 16u>*)
Reviewers: arsenm
Reviewed By: arsenm
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39295
llvm-svn: 316663
Summary: For some irreducible CFG the domtree nodes might be dead, do not update domtree for dead nodes.
Reviewers: kuhar, dberlin, hfinkel
Reviewed By: kuhar
Subscribers: llvm-commits, mcrosier
Differential Revision: https://reviews.llvm.org/D38960
llvm-svn: 316582
This patch adds a new pass for attaching !callees metadata to indirect call
sites. The pass propagates values to call sites by performing an IPSCCP-like
analysis using the generic sparse propagation solver. For indirect call sites
having a small set of possible callees, the attached metadata indicates what
those callees are. The metadata can be used to facilitate optimizations like
intersecting the function attributes of the possible callees, refining the call
graph, performing indirect call promotion, etc.
Differential Revision: https://reviews.llvm.org/D37355
llvm-svn: 316576
IRCE for unsigned latch conditions was temporarily disabled by rL314881. The motivating
example contained an unsigned latch condition and a signed range check. One of the safe
iteration ranges was `[1, SINT_MAX + 1]`. Its right border was incorrectly interpreted as a negative
value in `IntersectRange` function, this lead to a miscompile under which we deleted a range check
without inserting a postloop where it was needed.
This patch brings back IRCE for unsigned latch conditions. Now we treat range intersection more
carefully. If the latch condition was unsigned, we only try to consider a range check for deletion if:
1. The range check is also unsigned, or
2. Safe iteration range of the range check lies within `[0, SINT_MAX]`.
The same is done for signed latch.
Values from `[0, SINT_MAX]` are unambiguous, these values are non-negative under any interpretation,
and all values of a range intersected with such range are also non-negative.
We also use signed/unsigned min/max functions for range intersection depending on type of the
latch condition.
Differential Revision: https://reviews.llvm.org/D38581
llvm-svn: 316552
For a SCEV range, this patch replaces the naive emptiness check for SCEV ranges
which looks like `Begin == End` with a SCEV check. The range is guaranteed to be
empty of `Begin >= End`. We should filter such ranges out and do not try to perform
IRCE for them.
For example, we can get such range when intersecting range `[A, B)` and `[C, D)`
where `A < B < C < D`. The resulting range is `[max(A, C), min(B, D)) = [C, B)`.
This range is empty, but its `Begin` does not match with `End`.
Making IRCE for an empty range is basically safe but unprofitable because we
never actually get into the main loop where the range checks are supposed to
be eliminated. This patch uses SCEV mechanisms to treat loops with proved
`Begin >= End` as empty.
Differential Revision: https://reviews.llvm.org/D39082
llvm-svn: 316550
If particular target supports volatile memory access operations, we can
avoid AS casting to generic AS. Currently it's only enabled in NVPTX for
loads and stores that access global & shared AS.
Differential Revision: https://reviews.llvm.org/D39026
llvm-svn: 316495
Summary:
Kill the thread if operand 0 == false.
llvm.amdgcn.wqm.vote can be applied to the operand.
Also allow kill in all shader stages.
Reviewers: arsenm, nhaehnle
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D38544
llvm-svn: 316427
The `BasicBlock::getFirstInsertionPt` call may return `std::end` for the
BB. Dereferencing the end iterator results in an assertion failure
"(!NodePtr->isKnownSentinel()), function operator*". Ensure that the
returned iterator is valid before dereferencing it. If the end is
returned, move one position backward to get a valid insertion point.
llvm-svn: 316401
Summary:
The elts of ActivePreds which is defined as a SmallPtrSet are copied
into Blocks using std::copy. This makes the resultant order of Blocks
non-deterministic. We cannot simply sort Blocks as they need to match
the corresponding Values. So a better approach is to define ActivePreds
as SmallSetVector.
This fixes the following failures in
http://lab.llvm.org:8011/builders/reverse-iteration:
LLVM :: Transforms/GVNSink/indirect-call.ll
LLVM :: Transforms/GVNSink/sink-common-code.ll
LLVM :: Transforms/GVNSink/struct.ll
Reviewers: dberlin, jmolloy, bkramer, efriedma
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39025
llvm-svn: 316369
As discussed in D39011:
https://reviews.llvm.org/D39011
...replacing constants with a variable is inverting the transform done
by other IR passes, so we definitely don't want to do this early.
In fact, it's questionable whether this transform belongs in SimplifyCFG
at all. I'll look at moving this to codegen as a follow-up step.
llvm-svn: 316298
The missed canonicalization/optimization in the motivating test from PR34471 leads to very different codegen:
int switcher(int x) {
switch(x) {
case 17: return 17;
case 19: return 19;
case 42: return 42;
default: break;
}
return 0;
}
int comparator(int x) {
if (x == 17) return 17;
if (x == 19) return 19;
if (x == 42) return 42;
return 0;
}
For the first example, we use a bit-test optimization to avoid a series of compare-and-branch:
https://godbolt.org/g/BivDsw
Differential Revision: https://reviews.llvm.org/D39011
llvm-svn: 316293
The way that splitInnerLoopHeader splits blocks requires that
the induction PHI will be the first PHI in the inner loop
header. This makes sure that is actually the case when there
are both IV and reduction phis.
Differential Revision: https://reviews.llvm.org/D38682
llvm-svn: 316261
MergeFunctions uses (through FunctionComparator) a map of GlobalValues
to identifiers because it needs to compare functions and globals
do not have an inherent total order. Thus, FunctionComparator
(through GlobalNumberState) has a ValueMap<GlobalValue *>.
r315852 added a RAUW on globals that may have been previously
encountered by the FunctionComparator, which would replace
a GlobalValue * key with a ConstantExpr *, which is illegal.
This commit adjusts that code path to remove the function being
replaced from the ValueMap as well.
llvm-svn: 316145
Summary:
If a compare instruction is same or inverse of the compare in the
branch of the loop latch, then return a constant evolution node.
Currently scope of evaluation is limited to SCEV computation for
PHI nodes.
This shall facilitate computations of loop exit counts in cases
where compare appears in the evolution chain of induction variables.
Will fix PR 34538
Reviewers: sanjoy, hfinkel, junryoungju
Reviewed By: junryoungju
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38494
llvm-svn: 316054
Summary:
std::unordered_multimap happens to be very slow when the number of elements
grows large. On one of our internal applications we observed a 17x compile time
improvement from changing it to DenseMap.
Reviewers: mehdi_amini, serge-sans-paille, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38916
llvm-svn: 316045
This patch reverts rL315440 because of the bug described at
https://bugs.llvm.org/show_bug.cgi?id=34937
The fix for the bug is on review as D38944, but not yet ready. Given this is a regression reverting until a fix is ready is called for.
Max would have done the revert himself, but is having trouble doing a build of fresh LLVM for some reason. I did the build and test to ensure the revert worked as expected on his behalf.
llvm-svn: 315974
above PHI instructions.
ARC optimizer has an optimization that moves a call to an ObjC runtime
function above a phi instruction when the phi has a null operand and is
an argument passed to the function call. This optimization should not
kick in when the runtime function is an objc_release that releases an
object with precise lifetime semantics.
rdar://problem/34959669
llvm-svn: 315914
Summary:
The following transformation for cmp instruction:
icmp smin(x, PositiveValue), 0 -> icmp x, 0
should only be done after checking for min/max to prevent infinite
looping caused by a reverse canonicalization. That is why this
transformation was moved to place after the mentioned check.
Reviewers: spatel, efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38934
Patch by: Artur Gainullin <artur.gainullin@intel.com>
llvm-svn: 315895
This can result in significant code size savings in some cases,
e.g. an interrupt table all filled with the same assembly stub
in a certain Cortex-M BSP results in code blowup by a factor of 2.5.
Differential Revision: https://reviews.llvm.org/D34806
llvm-svn: 315853
This reduces code size for constructs like vtables or interrupt
tables that refer to functions in global initializers.
Differential Revision: https://reviews.llvm.org/D34805
llvm-svn: 315852
This avoid code duplication and allow us to add the disable unroll metadata elsewhere.
Differential Revision: https://reviews.llvm.org/D38928
llvm-svn: 315850
It is possible for both a base and a derived class to be satisfied
with a unique vtable. If a program contains casts of the same pointer
to both of those types, the CFI checks will be lowered to this
(with ThinLTO):
if (p != &__typeid_base_global_addr)
trap();
if (p != &__typeid_derived_global_addr)
trap();
The optimizer may then use the first condition combined
with the assumption that __typeid_base_global_addr and
__typeid_derived_global_addr may not alias to optimize away the second
comparison, resulting in an unconditional trap.
This patch fixes the bug by giving imported globals the type [0 x i8]*,
which prevents the optimizer from assuming that they do not alias.
Differential Revision: https://reviews.llvm.org/D38873
llvm-svn: 315753
This patch moves some common utility functions out of IPSCCP and makes them
available globally. The functions determine if interprocedural data-flow
analyses can propagate information through function returns, arguments, and
global variables.
Differential Revision: https://reviews.llvm.org/D37638
llvm-svn: 315719
Summary:
In RS4GC it is possible that a base pointer is contained in a vector that
has undergone a bitcast from one element-pointertype to another. We teach
RS4GC how to look through bitcasts of vector types when looking for a base
pointer.
Reviewers: anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38849
llvm-svn: 315694
Significantly reduces performancei (~30%) of gipfeli
(https://github.com/google/gipfeli)
I have not yet managed to reproduce this regression with the open-source
version of the benchmark on github, but will work with others to get a
reproducer to you later today.
llvm-svn: 315680
Summary:
This patch adds processing of binary operations when the def of operands are in
the same block (i.e. local processing).
Earlier we bailed out in such cases (the bail out was introduced in rL252032)
because LVI at that time was more precise about context at the end of basic
blocks, which implied local def and use analysis didn't benefit CVP.
Since then we've added support for LVI in presence of assumes and guards. The
test cases added show how local def processing in CVP helps adding more
information to the ashr, sdiv, srem and add operators.
Note: processCmp which suffers from the same problem will
be handled in a later patch.
Reviewers: philip, apilipenko, SjoerdMeijer, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38766
llvm-svn: 315634
This is a follow up for the loop predication change 313981 to support ule, sle latch predicates.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D38177
llvm-svn: 315616
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.
Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.
Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.
Differential Revision: https://reviews.llvm.org/D38406
llvm-svn: 315590
This reverts commit 4e4ee1c507e2707bb3c208e1e1b6551c3015cbf5.
This is failing due to some code that isn't built on MSVC
so I didn't catch. Not immediately obvious how to fix this
at first glance, so I'm reverting for now.
llvm-svn: 315536
There's a lot of misuse of Twine scattered around LLVM. This
ranges in severity from benign (returning a Twine from a function
by value that is just a string literal) to pretty sketchy (storing
a Twine by value in a class). While there are some uses for
copying Twines, most of the very compelling ones are confined
to the Twine class implementation itself, and other uses are
either dubious or easily worked around.
This patch makes Twine's copy constructor private, and fixes up
all callsites.
Differential Revision: https://reviews.llvm.org/D38767
llvm-svn: 315530
parameterized emit() calls
Summary: This is not functional change to adopt new emit() API added in r313691.
Reviewed By: anemet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38285
llvm-svn: 315476
This patch fixes the miscompile that happens when PRE hoists loads across guards and
other instructions that don't always pass control flow to their successors. PRE is now prohibited
to hoist across such instructions because there is no guarantee that the load standing after such
instruction is still valid before such instruction. For example, a load from under a guard may be
invalid before the guard in the following case:
int array[LEN];
...
guard(0 <= index && index < LEN);
use(array[index]);
Differential Revision: https://reviews.llvm.org/D37460
llvm-svn: 315440
Sinking of unordered atomic load into loop must be disallowed because it turns
a single load into multiple loads. The relevant section of the documentation
is: http://llvm.org/docs/Atomics.html#unordered, specifically the Notes for
Optimizers section. Here is the full text of this section:
> Notes for optimizers
> In terms of the optimizer, this **prohibits any transformation that
> transforms a single load into multiple loads**, transforms a store into
> multiple stores, narrows a store, or stores a value which would not be
> stored otherwise. Some examples of unsafe optimizations are narrowing
> an assignment into a bitfield, rematerializing a load, and turning loads
> and stores into a memcpy call. Reordering unordered operations is safe,
> though, and optimizers should take advantage of that because unordered
> operations are common in languages that need them.
Patch by Daniil Suchkov!
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D38392
llvm-svn: 315438
IRCE should not apply when the safe iteration range is proved to be empty.
In this case we do unneeded job creating pre/post loops and then never
go to the main loop.
This patch makes IRCE not apply to empty safe ranges, adds test for this
situation and also modifies one of existing tests where it used to happen
slightly.
Reviewed By: anna
Differential Revision: https://reviews.llvm.org/D38577
llvm-svn: 315437
Summary: In the current implementation, we only have accurate profile count for standalone symbols. For inlined functions, we do not have entry count data because it's not available in LBR. In this patch, we use the first instruction's frequency to estimiate the function's entry count, especially for inlined functions. This may be inaccurate due to debug info in optimized code. However, this is a better estimate than the static 80/20 estimation we have in the current implementation.
Reviewers: tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits, aprantl
Differential Revision: https://reviews.llvm.org/D38478
llvm-svn: 315369
Eliminate inttype phi with inttoptr/ptrtoint.
This version fixed a bug in finding the matching
phi -- the order of the incoming blocks may be
different (triggered in self build on Windows).
A new test case is added.
llvm-svn: 315272
There's at least one bug here - this code can fail with vector types (PR34856).
It's also being called for FREM; I'm still trying to understand how that is valid.
llvm-svn: 315127
This appears to be miscompiling Clang, as shown on two Windows bootstrap
bots:
http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/7611http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/6870
Nothing else is in the blame list. Both emit errors on this valid code
in the Windows ucrt headers:
C:\...\ucrt\malloc.h:95:32: error: invalid operands to binary expression ('char *' and 'int')
_Ptr = (char*)_Ptr + _ALLOCA_S_MARKER_SIZE;
~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~
I am attempting to reproduce this now.
This reverts r315044
llvm-svn: 315108
Summary: stripPointerCast is not reliably returning the value that's being type-casted. Instead it may look further at function attributes to further propagate the value. Instead of relying on stripPOintercast, the more reliable solution is to directly use the pointer to the promoted direct call.
Reviewers: tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D38603
llvm-svn: 315077
This is a vestige from the GCC-3 days, which disables IPO passes
when set. I don't think anybody actually uses it as there are
several IPO passes which still run with this flag set and
nobody complained/noticed. This reduces the delta between
current and new pass manager and allows us to easily review
the difference when we decide to flip the switch (or audit
which passes should run, FWIW).
llvm-svn: 315043
Summary:
If the extracted region has multiple exported data flows toward the same BB which is not included in the region, correct resotre instructions and PHI nodes won't be generated inside the exitStub. The solution is simply put the restore instructions right after the definition of output values instead of putting in exitStub.
Unittest for this bug is included.
Author: myhsu
Reviewers: chandlerc, davide, lattner, silvas, davidxl, wmi, kuhar
Subscribers: dberlin, kuhar, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D37902
llvm-svn: 315041
It is possible for two modules to define the same set of external
symbols without causing a duplicate symbol error at link time,
as long as each of the symbols is a comdat member. So we cannot
use them as part of a unique id for the module.
Differential Revision: https://reviews.llvm.org/D38602
llvm-svn: 315026
Summary: In SamplePGO, when an indirect call is promoted in the profiled binary, before profile annotation, it will be promoted and inlined. For the original indirect call, the current implementation will not mark VP profile on it. This is an issue when profile becomes stale. This patch annotates VP prof on indirect calls during annotation.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D38477
llvm-svn: 315016
The inliner performs some kind of dead code elimination as it goes,
but there are cases that are not really caught by it. We might
at some point consider teaching the inliner about them, but it
is OK for now to run GlobalOpt + GlobalDCE in tandem as their
benefits generally outweight the cost, making the whole pipeline
faster.
This fixes PR34652.
Differential Revision: https://reviews.llvm.org/D38154
llvm-svn: 314997
When ignoring a load that participates in an interleaved group, make sure to
move a cast that needs to sink after it.
Testcase derived from reproducer of PR34743.
Differential Revision: https://reviews.llvm.org/D38338
llvm-svn: 314986
Instead of trying to keep LastWidenRecipe updated after creating each recipe,
have tryToWiden() retrieve the last recipe of the current VPBasicBlock and check
if it's a VPWidenRecipe when attempting to extend its range. This ensures that
such extensions, optimized to maintain the original instruction order, do so
only when the instructions are to maintain their relative order. The latter does
not always hold, e.g., when a cast needs to sink to unravel first order
recurrence (r306884).
Testcase derived from reproducer of PR34711.
Differential Revision: https://reviews.llvm.org/D38339
llvm-svn: 314981
We were using an i1 type and then zero extending to a vector. Instead just create the 0/1 directly as a ConstantInt with the correct type. No need to ask ConstantExpr to zero extend for us.
This bug is a bit tricky to hit because it requires us to visit a zext of an icmp that would normally be simplified to true/false, but that icmp hasnt' been visited yet. In the test case this zext and icmp were created by visiting a udiv and due to worklist ordering we got to the zext first.
Fixes PR34841.
llvm-svn: 314971
Summary: This is to avoid e.g. merging two cheap icmps if the target is not going to expand to something nice later.
Reviewers: dberlin, spatel
Subscribers: davide, nemanjai
Differential Revision: https://reviews.llvm.org/D38232
llvm-svn: 314970
We can support ashr similar to lshr, if we know that none of the shifted in bits are used. In that case SimplifyDemandedBits would normally convert it to lshr. But that conversion doesn't happen if the shift has additional users.
Differential Revision: https://reviews.llvm.org/D38521
llvm-svn: 314945
This is a follow-up to https://reviews.llvm.org/D38138.
I fixed the capitalization of some functions because we're changing those
lines anyway and that helped verify that we weren't accidentally dropping
any options by using default param values.
llvm-svn: 314930
Recommitting r314517 with the fix for handling ConstantExpr.
Original commit message:
Currently, getGEPCost() returns TCC_FREE whenever a GEP is a legal addressing
mode in the target. However, since it doesn't check its actual users, it will
return FREE even in cases where the GEP cannot be folded away as a part of
actual addressing mode. For example, if an user of the GEP is a call
instruction taking the GEP as a parameter, then the GEP may not be folded in
isel.
llvm-svn: 314923
We have found some corner cases connected to range intersection where IRCE makes
a bad thing when the latch condition is unsigned. The fix for that will go as a follow up.
This patch temporarily disables IRCE for unsigned latch conditions until the issue is fixed.
The unsigned latch conditions were introduced to IRCE by rL310027.
Differential Revision: https://reviews.llvm.org/D38529
llvm-svn: 314881
All the buildbots are red, e.g.
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-lld/builds/2436/
> Summary:
> This patch tries to vectorize loads of consecutive memory accesses, accessed
> in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
> which was reverted back due to some basic issue with representing the 'use mask' of
> jumbled accesses.
>
> This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
>
> Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
>
> Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
>
> Reviewed By: Ayal
>
> Subscribers: hans, mzolotukhin
>
> Differential Revision: https://reviews.llvm.org/D36130
llvm-svn: 314824
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.
This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
Reviewed By: Ayal
Subscribers: hans, mzolotukhin
Differential Revision: https://reviews.llvm.org/D36130
llvm-svn: 314806
Apparently this works by virtue of the fact that the pointers are pointers to the APInts stored inside of the ConstantInt objects. But I really don't think we should be relying on that.
llvm-svn: 314761
Summary: If the merged instruction is call instruction, we need to set the scope to the closes common scope between 2 locations, otherwise it will cause trouble when the call is getting inlined.
Reviewers: dblaikie, aprantl
Reviewed By: dblaikie, aprantl
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D37877
llvm-svn: 314694
Summary: This currently uses ConstantExpr to do its math, but as noted in a TODO it can all be done directly on APInt.
Reviewers: spatel, majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38440
llvm-svn: 314640
And follow-up r314585.
Leads to segfaults. I'll forward reproduction instructions to the patch
author.
Also, for a recommit, still add the original patch description.
Otherwise, it becomes really tedious to find out what a patch actually
does. The fact that it is a recommit with a fix is somewhat secondary.
llvm-svn: 314622
Summary: In SamplePGO ThinLTO compile phase, we will not invoke ICP as it may introduce confusion to the 2nd annotation. This patch extracted that logic and makes it clearer before profile annotation. In the mean time, we need to make function importing process both inlined callsites as well as not promoted indirect callsites.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, mehdi_amini, llvm-commits, inglorion
Differential Revision: https://reviews.llvm.org/D38094
llvm-svn: 314619
This patch will eliminate redundant intptr/ptrtoint that pessimizes
analyses such as SCEV, AA and will make optimization passes such
as auto-vectorization more powerful.
Differential revision: http://reviews.llvm.org/D37832
llvm-svn: 314561
When type shrinking reductions, we should insert the truncations and extends at
the end of the loop latch block. Previously, these instructions were inserted
at the end of the loop header block. The difference is only a problem for loops
with predicated instructions (e.g., conditional stores and instructions that
may divide by zero). For these instructions, we create new basic blocks inside
the vectorized loop, which cause the loop header and latch to no longer be the
same block. This should fix PR34687.
Reference: https://bugs.llvm.org/show_bug.cgi?id=34687
llvm-svn: 314542
The type of a SCEVConstant may not match the corresponding LLVM Value.
In this case, we skip the constant folding for now.
TODO: Replace ConstantInt Zero by ConstantPointerNull
llvm-svn: 314531
Summary:
Currently, getGEPCost() returns TCC_FREE whenever a GEP is a legal addressing mode in the target.
However, since it doesn't check its actual users, it will return FREE even in cases
where the GEP cannot be folded away as a part of actual addressing mode.
For example, if an user of the GEP is a call instruction taking the GEP as a parameter,
then the GEP may not be folded in isel.
Reviewers: hfinkel, efriedma, mcrosier, jingyue, haicheng
Reviewed By: hfinkel
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38085
llvm-svn: 314517
JumpThreading now preserves dominance and lazy value information across the
entire pass. The pass manager is also informed of this preservation with
the goal of DT and LVI being recalculated fewer times overall during
compilation.
This change prepares JumpThreading for enhanced opportunities; particularly
those across loop boundaries.
Patch by: Brian Rzycki <b.rzycki@samsung.com>,
Sebastian Pop <s.pop@samsung.com>
Differential revision: https://reviews.llvm.org/D37528
llvm-svn: 314435
Summary:
And now that we no longer have to explicitly free() the Loop instances, we can
(with more ease) use the destructor of LoopBase to do what LoopBase::clear() was
doing.
Reviewers: chandlerc
Subscribers: mehdi_amini, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38201
llvm-svn: 314375
This reverts r314017 and similar code added in later commits. It seems to not work for pointer compares and is causing a bot failure for the last several days.
llvm-svn: 314360
reductions.
If both operands of the newly created SelectInst are Undefs the
resulting operation is also Undef, not SelectInst. It may cause crashes
when trying to propagate IR flags because function expects exactly
SelectInst instruction, nothing else.
llvm-svn: 314323
These changes faciliate positive behavior for arithmetic based select
expressions that match its translation criteria, keeping code size gated to
neutral or improved scenarios.
Patch by Michael Berg <michael_c_berg@apple.com>!
Differential Revision: https://reviews.llvm.org/D38263
llvm-svn: 314320
This was intended to be no-functional-change, but it's not - there's a test diff.
So I thought I should stop here and post it as-is to see if this looks like what was expected
based on the discussion in PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603
Notes:
1. The test improvement occurs because the existing 'LateSimplifyCFG' marker is not carried
through the recursive calls to 'SimplifyCFG()->SimplifyCFGOpt().run()->SimplifyCFG()'.
The parameter isn't passed down, so we pick up the default value from the function signature
after the first level. I assumed that was a bug, so I've passed 'Options' down in all of the
'SimplifyCFG' calls.
2. I split 'LateSimplifyCFG' into 2 bits: ConvertSwitchToLookupTable and KeepCanonicalLoops.
This would theoretically allow us to differentiate the transforms controlled by those params
independently.
3. We could stash the optional AssumptionCache pointer and 'LoopHeaders' pointer in the struct too.
I just stopped here to minimize the diffs.
4. Similarly, I stopped short of messing with the pass manager layer. I have another question that
could wait for the follow-up: why is the new pass manager creating the pass with LateSimplifyCFG
set to true no matter where in the pipeline it's creating SimplifyCFG passes?
// Create an early function pass manager to cleanup the output of the
// frontend.
EarlyFPM.addPass(SimplifyCFGPass());
-->
/// \brief Construct a pass with the default thresholds
/// and switch optimizations.
SimplifyCFGPass::SimplifyCFGPass()
: BonusInstThreshold(UserBonusInstThreshold),
LateSimplifyCFG(true) {} <-- switches get converted to lookup tables and loops may not be in canonical form
If this is unintended, then it's possible that the current behavior of dropping the 'LateSimplifyCFG'
setting via recursion was masking this bug.
Differential Revision: https://reviews.llvm.org/D38138
llvm-svn: 314308
This patch tries to transform cases like:
for (unsigned i = 0; i < N; i += 2) {
bool c0 = (i & 0x1) == 0;
bool c1 = ((i + 1) & 0x1) == 1;
}
To
for (unsigned i = 0; i < N; i += 2) {
bool c0 = true;
bool c1 = true;
}
This commit also update test/Transforms/IndVarSimplify/replace-srem-by-urem.ll to prevent constant folding.
Differential Revision: https://reviews.llvm.org/D38272
llvm-svn: 314266
Summary:
Don't bail out on constant divisors for divisions that can be narrowed without
introducing control flow . This gives us a 32 bit multiply instead of an
emulated 64 bit multiply in the generated PTX assembly.
Reviewers: jlebar
Subscribers: jholewinski, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38265
llvm-svn: 314253
If this transformation succeeds, we're going to remove our dependency on the shift by rewriting the and. So it doesn't matter how many uses the shift has.
This distributes the one use check to other transforms in foldICmpAndConstConst that do need it.
Differential Revision: https://reviews.llvm.org/D38206
llvm-svn: 314233
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074
In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.
Original commit message (authored by Filipe Cabecinhas):
This fixes PR31777.
If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.
In the future we should also support vectors of integers. And maybe
float/double if we can.
Differential Revision: https://reviews.llvm.org/D30703
llvm-svn: 314206
Usually the frontend communicates the size of wchar_t via metadata and
we can optimize wcslen (and possibly other calls in the future). In
cases without the wchar_size metadata we would previously try to guess
the correct size based on the target triple; however this is fragile to
keep up to date and may miss users manually changing the size via flags.
Better be safe and stop guessing and optimizing if the frontend didn't
communicate the size.
Differential Revision: https://reviews.llvm.org/D38106
llvm-svn: 314185
Summary:
Sanitizer blacklist entries currently apply to all sanitizers--there
is no way to specify that an entry should only apply to a specific
sanitizer. This is important for Control Flow Integrity since there are
several different CFI modes that can be enabled at once. For maximum
security, CFI blacklist entries should be scoped to only the specific
CFI mode(s) that entry applies to.
Adding section headers to SpecialCaseLists allows users to specify more
information about list entries, like sanitizer names or other metadata,
like so:
[section1]
fun:*fun1*
[section2|section3]
fun:*fun23*
The section headers are regular expressions. For backwards compatbility,
blacklist entries entered before a section header are put into the '[*]'
section so that blacklists without sections retain the same behavior.
SpecialCaseList has been modified to also accept a section name when
matching against the blacklist. It has also been modified so the
follow-up change to clang can define a derived class that allows
matching sections by SectionMask instead of by string.
Reviewers: pcc, kcc, eugenis, vsk
Reviewed By: eugenis, vsk
Subscribers: vitalybuka, llvm-commits
Differential Revision: https://reviews.llvm.org/D37924
llvm-svn: 314170
All this optimization cares about is knowing how many low bits of LHS is known to be zero and whether that means that the result is 0 or greater than the RHS constant. It doesn't matter where the zeros in the low bits came from. So we don't need to specifically look for an AND. Instead we can use known bits.
Differential Revision: https://reviews.llvm.org/D38195
llvm-svn: 314153
The 1st attempt at this:
https://reviews.llvm.org/rL314117
was reverted at:
https://reviews.llvm.org/rL314118
because of bot fails for clang tests that were checking optimized IR. That should be fixed with:
https://reviews.llvm.org/rL314144
...so try again.
Original commit message:
The transform to convert an extract-of-a-select-of-vectors was added at:
https://reviews.llvm.org/rL194013
And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>
Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.
The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.
The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.
Differential Revision: https://reviews.llvm.org/D38006
llvm-svn: 314147
Since now SCEV can handle 'urem', an 'urem' is a better canonical form than an 'srem' because it has well-defined behavior
This is a follow up of D34598
Differential Revision: https://reviews.llvm.org/D38072
llvm-svn: 314125
The transform to convert an extract-of-a-select-of-vectors was added at:
rL194013
And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>
Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.
The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.
The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.
Differential Revision: https://reviews.llvm.org/D38006
llvm-svn: 314117
The result of the isSignBitCheck isn't used anywhere else and this allows us to share the m_APInt call in the likely case that it isn't a sign bit check.
llvm-svn: 314018
We've found a serious issue with the current implementation of loop predication.
The current implementation relies on SCEV and this turned out to be problematic.
To fix the problem we had to rework the pass substantially. We have had the
reworked implementation in our downstream tree for a while. This is the initial
patch of the series of changes to upstream the new implementation.
For now the transformation is limited to the following case:
* The loop has a single latch with either ult or slt icmp condition.
* The step of the IV used in the latch condition is 1.
* The IV of the latch condition is the same as the post increment IV of the guard condition.
* The guard condition is ult.
See the review or the LoopPredication.cpp header for the details about the
problem and the new implementation.
Reviewed By: sanjoy, mkazantsev
Differential Revision: https://reviews.llvm.org/D37569
llvm-svn: 313981
The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+ if (DII == InsertBefore)
+ InsertBefore = &*std::next(InsertBefore->getIterator());
DII->eraseFromParent();
I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.
The reduced C test case for this was:
void useit(int*);
static inline void inlineme() {
int x[2];
useit(x);
}
void f() {
inlineme();
inlineme();
}
llvm-svn: 313905
.. as well as the two subsequent changes r313826 and r313875.
This leads to segfaults in combination with ASAN. Will forward repro
instructions to the original author (rnk).
llvm-svn: 313876
Summary:
There already was code that tried to remove the dbg.declare, but that code
was placed after we had called
I->replaceAllUsesWith(UndefValue::get(I->getType()));
on the alloca, so when we searched for the relevant dbg.declare, we
couldn't find it.
Now we do the search before we call RAUW so there is a chance to find it.
An existing testcase needed update due to this. Two dbg.declare with undef
were removed and then suddenly one of the two CHECKS failed.
Before this patch we got
call void @llvm.dbg.declare(metadata i24* undef, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15
call void @llvm.dbg.declare(metadata %struct.prog_src_register* undef, metadata !14, metadata !DIExpression()), !dbg !15
call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 32)), !dbg !15
call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15
and with it we get
call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 32)), !dbg !15
call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15
However, the CHECKs in the testcase checked things in a silly order, so
they only passed since they found things in the first dbg.declare. Now
we changed the order of the checks and the test passes.
Reviewers: rnk
Reviewed By: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37900
llvm-svn: 313875
This patch contains fix for reverted commit
rL312318 which was causing failure due to use
of unchecked dyn_cast to CIInit.
Patch by: Nikola Prica.
llvm-svn: 313870
Revert the patch causing the functional failures.
The patch owner is notified with test cases which fail.
Test case has been provided to Maxim offline.
llvm-svn: 313857
I noticed this inefficiency while investigating PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603
This fix will likely push another bug (we don't maintain state of 'LateSimplifyCFG')
into hiding, but I'll try to clean that up with a follow-up patch anyway.
llvm-svn: 313829
Summary:
This implements the design discussed on llvm-dev for better tracking of
variables that live in memory through optimizations:
http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html
This is tracked as PR34136
llvm.dbg.addr is intended to be produced and used in almost precisely
the same way as llvm.dbg.declare is today, with the exception that it is
control-dependent. That means that dbg.addr should always have a
position in the instruction stream, and it will allow passes that
optimize memory operations on local variables to insert llvm.dbg.value
calls to reflect deleted stores. See SourceLevelDebugging.rst for more
details.
The main drawback to generating DBG_VALUE machine instrs is that they
usually cause LLVM to emit a location list for DW_AT_location. The next
step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE
ranges as not needing a location list, and possibly start setting
DW_AT_start_offset for variables whose lifetimes begin mid-scope.
Reviewers: aprantl, dblaikie, probinson
Subscribers: eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37768
llvm-svn: 313825
We already did (X & C2) > C1 --> (X & C2) != 0, if any bit set in (X & C2) will produce a result greater than C1. But there is an equivalent inverse condition with <= C1 (which will be canonicalized to < C1+1)
Differential Revision: https://reviews.llvm.org/D38065
llvm-svn: 313819
This broke the buildbots, e.g.
http://bb.pgr.jp/builders/test-llvm-i686-linux-RA/builds/391
> Summary:
> This patch tries to vectorize loads of consecutive memory accesses, accessed
> in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
> which was reverted back due to some basic issue with representing the 'use mask'
> jumbled accesses.
>
> This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
>
> Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
>
> Subscribers: mzolotukhin
>
> Reviewed By: ayal
>
> Differential Revision: https://reviews.llvm.org/D36130
>
> Review comments updated accordingly
>
> Change-Id: I22ab0a8a9bac9d49d74baa81a08e1e486f5e75f0
>
> Added a TODO for sortLoadAccesses API
>
> Change-Id: I3c679bf1865422d1b45e17ea28f1992bca660b58
>
> Modified the TODO for sortLoadAccesses API
>
> Change-Id: Ie64a66cb5f9e2a7610438abb0e750c6e090f9565
>
> Review comment update for using OpdNum to insert the mask in respective location
>
> Change-Id: I016d0c1b29874e979efc0205bbf078991f92edce
>
> Fixes '-Wsign-compare warning' in LoopAccessAnalysis.cpp and code rebase
>
> Change-Id: I64b2ea5e68c1d7b6a028f5ef8251c5a97333f89b
llvm-svn: 313781
In these cases, two selects have constant selectable operands for
both the true and false components and have the same conditional
expression.
We then create two arithmetic operations of the same type and feed a
final select operation using the result of the true arithmetic for the true
operand and the result of the false arithmetic for the false operand and reuse
the original conditionl expression.
The arithmetic operations are naturally folded as a consequence, leaving
only the newly formed select to replace the old arithmetic operation.
Patch by: Michael Berg <michael_c_berg@apple.com>
Differential Revision: https://reviews.llvm.org/D37019
llvm-svn: 313774
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask'
jumbled accesses.
This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
Subscribers: mzolotukhin
Reviewed By: ayal
Differential Revision: https://reviews.llvm.org/D36130
Review comments updated accordingly
Change-Id: I22ab0a8a9bac9d49d74baa81a08e1e486f5e75f0
Added a TODO for sortLoadAccesses API
Change-Id: I3c679bf1865422d1b45e17ea28f1992bca660b58
Modified the TODO for sortLoadAccesses API
Change-Id: Ie64a66cb5f9e2a7610438abb0e750c6e090f9565
Review comment update for using OpdNum to insert the mask in respective location
Change-Id: I016d0c1b29874e979efc0205bbf078991f92edce
Fixes '-Wsign-compare warning' in LoopAccessAnalysis.cpp and code rebase
Change-Id: I64b2ea5e68c1d7b6a028f5ef8251c5a97333f89b
llvm-svn: 313771
Summary:
The fix for dead stripping analysis in the case of SamplePGO indirect
calls to local functions (r313151) introduced the possibility of an
infinite loop.
Make sure we check for the value being already live after we update it
for SamplePGO indirect call handling.
Reviewers: danielcdh
Subscribers: mehdi_amini, inglorion, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D38086
llvm-svn: 313766
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.
This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
Reviewed By: Ayal
Subscribers: mzolotukhin
Differential Revision: https://reviews.llvm.org/D36130
Commit after rebase for patch D36130
Change-Id: I8add1c265455669ef288d880f870a9522c8c08ab
llvm-svn: 313736
Summary:
With this change:
- Methods in LoopBase trip an assert if the receiver has been invalidated
- LoopBase::clear frees up the memory held the LoopBase instance
This change also shuffles things around as necessary to work with this stricter invariant.
Reviewers: chandlerc
Subscribers: mehdi_amini, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38055
llvm-svn: 313708
Summary:
See comment for why I think this is a good idea.
This change also:
- Removes an SCEV test case. The SCEV test was not testing anything useful (most of it was `#if 0` ed out) and it would need to be updated to deal with a private ~Loop::Loop.
- Updates the loop pass manager test case to deal with a private ~Loop::Loop.
- Renames markAsRemoved to markAsErased to contrast with removeLoop, via the usual remove vs. erase idiom we already have for instructions and basic blocks.
Reviewers: chandlerc
Subscribers: mehdi_amini, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D37996
llvm-svn: 313695
In the lambda we are now returning the remark by value so we need to preserve
its type in the insertion operator. This requires making the insertion
operator generic.
I've also converted a few cases to use the new API. It seems to work pretty
well. See the LoopUnroller for a slightly more interesting case.
llvm-svn: 313691
Summary: In the ThinLTO compilation, if a function is inlined in the profiling binary, we need to inline it before annotation. If the callee is not available in the primary module, a first step is needed to import that callee function. For the current implementation, if the call is an indirect call, which has been promoted to >1 targets and inlined, SamplePGO will only import one target with the largest sample count. This patch fixed the bug to import all targets instead.
Reviewers: tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D36637
llvm-svn: 313678
Summary: Fix the bug when promoted call return type mismatches with the promoted function, we should not try to inline it. Otherwise it may lead to compiler crash.
Reviewers: davidxl, tejohnson, eraman
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D38018
llvm-svn: 313658
I've moved the test cases from the InstCombine optimizations to the backend to keep the coverage we had there. It covered every possible immediate so I've preserved the resulting shuffle mask for each of those immediates.
llvm-svn: 313450
CostModel.
The original patch added support for horizontal min/max reductions to
the SLP vectorizer.
This patch causes LLVM to miscompile fairly simple signed min
reductions. I have attached a test progrom to http://llvm.org/PR34635
that shows the behavior change after this patch. We found this in a test
for the open source Eigen library, but also in other code.
Unfortunately, the revert is moderately challenging. It required
reverting:
r313042: [SLP] Test with multiple uses of conditional op and wrong parent.
r312853: [SLP] Fix buildbots, NFC.
r312793: [SLP] Fix the warning about paths not returning the value, NFC.
r312791: [SLP] Support for horizontal min/max reduction.
And even then, I had to completely skip reverting the changes to TTI and
CostModel because r312832 rewrote so much of this code. Plus, the cost
modeling changes aren implicated in the miscompile, so they should be
fine and will just not be used until this gets re-introduced.
llvm-svn: 313409
It enables OptimizationRemarkEmitter::allowExtraAnalysis and MachineOptimizationRemarkEmitter::allowExtraAnalysis to return true not only for -fsave-optimization-record but when specific remarks are requested with
command line options.
The diagnostic handler used to be callback now this patch adds a class
DiagnosticHandler. It has virtual method to provide custom diagnostic handler
and methods to control which particular remarks are enabled.
However LLVM-C API users can still provide callback function for diagnostic handler.
llvm-svn: 313390
It enables OptimizationRemarkEmitter::allowExtraAnalysis and MachineOptimizationRemarkEmitter::allowExtraAnalysis to return true not only for -fsave-optimization-record but when specific remarks are requested with
command line options.
The diagnostic handler used to be callback now this patch adds a class
DiagnosticHandler. It has virtual method to provide custom diagnostic handler
and methods to control which particular remarks are enabled.
However LLVM-C API users can still provide callback function for diagnostic handler.
llvm-svn: 313382
Add a profitability heuristic to enable runtime unrolling of multi-exit
loop: There can be atmost two unique exit blocks for the loop and the
second exit block should be a deoptimizing block. Also, there can be one
other exiting block other than the latch exiting block. The reason for
the latter is so that we limit the number of branches in the unrolled
code to being at most the unroll factor. Deoptimizing blocks are rarely
taken so these additional number of branches created due to the
unrolling are predictable, since one of their target is the deopt block.
Reviewers: apilipenko, reames, evstupac, mkuper
Subscribers: llvm-commits
Reviewed by: reames
Differential Revision: https://reviews.llvm.org/D35380
llvm-svn: 313363
During runtime unrolling on loops with multiple exits, we update the
exit blocks with the correct phi values from both original and remainder
loop.
In this process, we lookup the VMap for the mapped incoming phi values,
but did not update the VMap if a default entry was generated in the VMap
during the lookup. This default value is generated when constants or
values outside the current loop are looked up.
This patch fixes the assertion failure when null entries are present in
the VMap because of this lookup. Added a testcase that showcases the
problem.
llvm-svn: 313358
Patch tries to improve vectorization of the following code:
void add1(int * __restrict dst, const int * __restrict src) {
*dst++ = *src++;
*dst++ = *src++ + 1;
*dst++ = *src++ + 2;
*dst++ = *src++ + 3;
}
Allows to vectorize even if the very first operation is not a binary add, but just a load.
Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev, davide
Subscribers: llvm-commits, RKSimon
Differential Revision: https://reviews.llvm.org/D28907
llvm-svn: 313348
Summary: Move to LoopUtils method that collects all children of a node inside a loop.
Reviewers: majnemer, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37870
llvm-svn: 313322
Summary: SampleProfileLoader inlines hot functions if it is inlined in the profiled binary. However, the inline needs to be guarded by legality check, otherwise it could lead to correctness issues.
Reviewers: eraman, davidxl
Reviewed By: eraman
Subscribers: vitalybuka, sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D37779
llvm-svn: 313277
This patch fixes pr34283, which exposed that the computation of
maximum legal width for vectorization was wrong, because it relied
on MaxInterleaveFactor to obtain the maximum stride used in the loop,
however not all strided accesses in the loop have an interleave-group
associated with them.
Instead of recording the maximum stride in the loop, which can be over
conservative (e.g. if the access with the maximum stride is not involved
in the dependence limitation), this patch tracks the actual maximum legal
width imposed by accesses that are involved in dependencies.
Differential Revision: https://reviews.llvm.org/D37507
llvm-svn: 313237
This reland includes a fix for the LowerTypeTests pass so that it
looks past aliases when determining which type identifiers are live.
Differential Revision: https://reviews.llvm.org/D37842
llvm-svn: 313229
This broke Chromium's CFI build; see crbug.com/765004.
> We were previously handling aliases during dead stripping by adding
> the aliased global's "original name" GUID to the worklist. This will
> lead to incorrect behaviour if the global has local linkage because
> the original name GUID will not correspond to the global's GUID in
> the summary.
>
> Because an alias is just another name for the global that it
> references, there is no need to mark the referenced global as used,
> or to follow references from any other copies of the global. So all
> we need to do is to follow references from the aliasee's summary
> instead of the alias.
>
> Differential Revision: https://reviews.llvm.org/D37789
llvm-svn: 313222
Summary: SampleProfileLoader inlines hot functions if it is inlined in the profiled binary. However, the inline needs to be guarded by legality check, otherwise it could lead to correctness issues.
Reviewers: eraman, davidxl
Reviewed By: eraman
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D37779
llvm-svn: 313195
These are changes to reduce redundant computations when calculating a
feasible vectorization factor:
1. early return when target has no vector registers
2. don't compute register usage for the default VF.
Suggested during review for D37702.
llvm-svn: 313176
Summary:
Added text options to -pgo-view-counts and -pgo-view-raw-counts that dump block frequency and branch probability info in text.
This is useful when the graph is very large and complex (the dot command crashes, lines/edges too close to tell apart, hard to navigate without textual search) or simply when text is preferred.
Reviewers: davidxl
Reviewed By: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37776
llvm-svn: 313159
We were previously handling aliases during dead stripping by adding
the aliased global's "original name" GUID to the worklist. This will
lead to incorrect behaviour if the global has local linkage because
the original name GUID will not correspond to the global's GUID in
the summary.
Because an alias is just another name for the global that it
references, there is no need to mark the referenced global as used,
or to follow references from any other copies of the global. So all
we need to do is to follow references from the aliasee's summary
instead of the alias.
Differential Revision: https://reviews.llvm.org/D37789
llvm-svn: 313157
Summary:
SamplePGO indirect call profiles record the target as the original GUID
for statics. The importer had special handling to map to the normal GUID
in that case. The dead global analysis needs the same treatment or
inconsistencies arise, resulting in linker unsats due to some dead
symbols being exported and kept, leaving in references to other dead
symbols that are removed.
This can happen when a SamplePGO profile collected by one binary is used
for a different binary, so the indirect call profiles may not accurately
reflect live targets.
Reviewers: danielcdh
Subscribers: mehdi_amini, inglorion, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D37783
llvm-svn: 313151
When converting a PHI into a series of 'select' instructions to combine the
incoming values together according their edge masks, initialize the first
value to the incoming value In0 of the first predecessor, instead of
generating a redundant assignment 'select(Cond[0], In0, In0)'. The latter
fails when the Cond[0] mask is null, representing a full mask, which can
happen only when there's a single incoming value.
No functional changes intended nor expected other than surviving null Cond[0]'s.
This fix follows D35725, which introduced using null to represent full masks.
Differential Revision: https://reviews.llvm.org/D37619
llvm-svn: 313119
Factor out the reachability such that multiple queries to find reachability of values are fast. This is based on finding
the ANTIC points
in the CFG which do not change during hoisting. The ANTIC points are basically the dominance-frontiers in the inverse
graph. So we introduce a data structure (CHI nodes)
to keep track of values flowing out of a basic block. We only do this for values with multiple occurrences in the
function as they are the potential hoistable candidates.
This patch allows us to hoist instructions to a basic block with >2 successors, as well as deal with infinite loops in a
trivial way.
Relevant test cases are added to show the functionality as well as regression fixes from PR32821.
Regression from previous GVNHoist:
We do not hoist fully redundant expressions because fully redundant expressions are already handled by NewGVN
Differential Revision: https://reviews.llvm.org/D35918
Reviewers: dberlin, sebpop, gberry,
llvm-svn: 313116
Summary:
This should improve optimized debug info for address-taken variables at
the cost of inaccurate debug info in some situations.
We patched this into clang and deployed this change to Chromium
developers, and this significantly improved debuggability of optimized
code. The long-term solution to PR34136 seems more and more like it's
going to take a while, so I would like to commit this change under a
flag so that it can be used as a stop-gap measure.
This flag should really help so for C++ aggregates like std::string and
std::vector, which are typically address-taken, even after inlining, and
cannot be SROA-ed.
Reviewers: aprantl, dblaikie, probinson, dberlin
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D36596
llvm-svn: 313108
Summary: This change passes down ACT to SampleProfileLoader for the new PM. Also remove the default value for SampleProfileLoader class as it is not used.
Reviewers: eraman, davidxl
Reviewed By: eraman
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D37773
llvm-svn: 313080
Summary:
The current promoteLoopAccessesToScalars method receives an AliasSet, but
the information used is in fact a list of Value*, known to must alias.
Create the list ahead of time to make this method independent of the AliasSet class.
While there is no functionality change, this adds overhead for creating
a set of Value*, when promotion would normally exit earlier.
This is meant to be as a first refactoring step in order to start replacing
AliasSetTracker with MemorySSA.
And while the end goal is to redesign LICM, the first few steps will focus on
adding MemorySSA as an alternative to the AliasSetTracker using most of the
existing functionality.
Reviewers: mkuper, danielcdh, dberlin
Subscribers: sanjoy, chandlerc, gberry, davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D35439
llvm-svn: 313075
Summary:
When the MaxVectorSize > ConstantTripCount, we should just clamp the
vectorization factor to be the ConstantTripCount.
This vectorizes loops where the TinyTripCountThreshold >= TripCount < MaxVF.
Earlier we were finding the maximum vector width, which could be greater than
the trip count itself. The Loop vectorizer does all the work for generating a
vectorizable loop, but in the end we would always choose the scalar loop (since
the VF > trip count). This allows us to choose the VF keeping in mind the trip
count if available.
This is a fix on top of rL312472.
Reviewers: Ayal, zvi, hfinkel, dneilson
Reviewed by: Ayal
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37702
llvm-svn: 313046
Not all targets support the use of absolute symbols to export
constants. In particular, ARM has a wide variety of constant encodings
that cannot currently be relocated by linkers. So instead of exporting
the constants using symbols, export them directly in the summary.
The values of the constants are left as zeroes on targets that support
symbolic exports.
This may result in more cache misses when targeting those architectures
as a result of arbitrary changes in constant values, but this seems
somewhat unavoidable for now.
Differential Revision: https://reviews.llvm.org/D37407
llvm-svn: 312967
It now knows the tricks of both functions.
Also, fix a bug that considered allocas of non-zero address space to be always non null
Differential Revision: https://reviews.llvm.org/D37628
llvm-svn: 312869
This is intended to be a superset of the functionality from D31037 (EarlyCSE) but implemented
as an independent pass, so there's no stretching of scope and feature creep for an existing pass.
I also proposed a weaker version of this for SimplifyCFG in D30910. And I initially had almost
this same functionality as an addition to CGP in the motivating example of PR31028:
https://bugs.llvm.org/show_bug.cgi?id=31028
The advantage of positioning this ahead of SimplifyCFG in the pass pipeline is that it can allow
more flattening. But it needs to be after passes (InstCombine) that could sink a div/rem and
undo the hoisting that is done here.
Decomposing remainder may allow removing some code from the backend (PPC and possibly others).
Differential Revision: https://reviews.llvm.org/D37121
llvm-svn: 312862
SLP vectorizer supports horizontal reductions for Add/FAdd binary
operations. Patch adds support for horizontal min/max reductions.
Function getReductionCost() is split to getArithmeticReductionCost() for
binary operation reductions and getMinMaxReductionCost() for min/max
reductions.
Patch fixes PR26956.
Differential revision: https://reviews.llvm.org/D27846
llvm-svn: 312791
This is required when targeting COFF, as the comdat name must match
one of the names of the symbols in the comdat.
Differential Revision: https://reviews.llvm.org/D37550
llvm-svn: 312767
r312318 - Debug info for variables whose type is shrinked to bool
r312325, r312424, r312489 - Test case for r312318
Revision 312318 introduced a null dereference bug.
Details in https://bugs.llvm.org/show_bug.cgi?id=34490
llvm-svn: 312758
Consider this type of a loop:
for (...) {
...
if (...) continue;
...
}
Normally, the "continue" would branch to the loop control code that
checks whether the loop should continue iterating and which contains
the (often) unique loop latch branch. In certain cases jump threading
can "thread" the inner branch directly to the loop header, creating
a second loop latch. Loop canonicalization would then transform this
loop into a loop nest. The problem with this is that in such a loop
nest neither loop is countable even if the original loop was. This
may inhibit subsequent loop optimizations and be detrimental to
performance.
Differential Revision: https://reviews.llvm.org/D36404
llvm-svn: 312664
This is a preliminary step towards solving the remaining part of PR27145 - IR for isfinite():
https://bugs.llvm.org/show_bug.cgi?id=27145
In order to solve that one more generally, we need to add matching for and/or of fcmp ord/uno
with a constant operand.
But while looking at those patterns, I realized we were missing a canonicalization for nonzero
constants. Rather than limiting to just folds for constants, we're adding a general value
tracking method for this based on an existing DAG helper.
By transforming everything to 0.0, we can simplify the existing code in foldLogicOfFCmps()
and pick up missing vector folds.
Differential Revision: https://reviews.llvm.org/D37427
llvm-svn: 312591
Instead of creating a Constant and then calling m_APInt with it (which will always return true). Just create an APInt initially, and use that for the checks in isSelect01 function. If it turns out we do need the Constant, create it from the APInt.
This is a refactor for a future patch that will do some more checks of the constant values here.
llvm-svn: 312517
Summary:
Improve how MaxVF is computed while taking into account that MaxVF should not be larger than the loop's trip count.
Other than saving on compile-time by pruning the possible MaxVF candidates, this patch fixes pr34438 which exposed the following flow:
1. Short trip count identified -> Don't bail out, set OptForSize:=True to avoid tail-loop and runtime checks.
2. Compute MaxVF returned 16 on a target supporting AVX512.
3. OptForSize -> choose VF:=MaxVF.
4. Bail out because TripCount = 8, VF = 16, TripCount % VF !=0 means we need a tail loop.
With this patch step 2. will choose MaxVF=8 based on TripCount.
Reviewers: Ayal, dorit, mkuper, hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D37425
llvm-svn: 312472
Debug information can be, and was, corrupted when the runtime
remainder loop was fully unrolled. This is because a !null node can
be created instead of a unique one describing the loop. In this case,
the original node gets incorrectly updated with the NewLoopID
metadata.
In the case when the remainder loop is going to be quickly fully
unrolled, there isn't the need to add loop metadata for it anyway.
Differential Revision: https://reviews.llvm.org/D37338
llvm-svn: 312471
In addition to removing chunks of duplicated code, we don't
want these to diverge. If there's a fold for one, there
should be a fold of the other via DeMorgan's Laws.
llvm-svn: 312420
We had these locals:
Value *Op0RHS = LHS->getOperand(1);
Value *Op1LHS = RHS->getOperand(0);
...so we confusingly transposed the meaning of left/right and op0/op1.
llvm-svn: 312418
This makes it easier to see that they're almost duplicates.
As with the similar icmp functions, there should be identical
folds for both logic ops because those are DeMorganized variants.
llvm-svn: 312415
Summary:
After a discussion with Rekka, i believe this (or a small variant)
should fix the remaining phi-of-ops problems.
Rekka's algorithm for completeness relies on looking up expressions
that should have no leader, and expecting it to fail (IE looking up
expressions that can't exist in a predecessor, and expecting it to
find nothing).
Unfortunately, sometimes these expressions can be simplified to
constants, but we need the lookup to fail anyway. Additionally, our
simplifier outsmarts this by taking these "not quite right"
expressions, and simplifying them into other expressions or walking
through phis, etc. In the past, we've sometimes been able to find
leaders for these expressions, incorrectly.
This change causes us to not to try to phi of ops such expressions.
We determine safety by seeing if they depend on a phi node in our
block.
This is not perfect, we can do a bit better, but this should be a
"correctness start" that we can then improve. It also requires a
bunch of caching that i'll eventually like to eliminate.
The right solution, longer term, to the simplifier issues, is to make
the query interface for the instruction simplifier/constant folder
have the flags we need, so that we can keep most things going, but
turn off the possibly-invalid parts (threading through phis, etc).
This is an issue in another wrong code bug as well.
Reviewers: davide, mcrosier
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D37175
llvm-svn: 312401
This patch teaches decomposeBitTestICmp to look through truncate instructions on the input to the compare. If a truncate is found it will now return the pre-truncated Value and appropriately extend the APInt mask.
This allows some code to be removed from InstSimplify that was doing this functionality.
This allows InstCombine's bit test combining code to match a pre-truncate Value with the same Value appear with an 'and' on another icmp. Or it allows us to combine a truncate to i16 and a truncate to i8. This also required removing the type check from the beginning of getMaskedTypeForICmpPair, but I believe that's ok because we still have to find two values from the input to each icmp that are equal before we'll do any transformation. So the type check was really just serving as an early out.
There was one user of decomposeBitTestICmp that didn't want to look through truncates, so I've added a flag to prevent that behavior when necessary.
Differential Revision: https://reviews.llvm.org/D37158
llvm-svn: 312382
A future patch will make the code look through truncates feeding the compare. So the compares might be different types but the pretruncated types might be the same.
This should be safe because we still require the same Value* to be used truncated or not in both compares. So that serves to ensure the types are the same.
llvm-svn: 312381
Previously we used the type from the LHS of the compare, but a future patch will change decomposeBitTestICmp to look through truncates so it will return a pretruncated Value* and the type needs to match that.
llvm-svn: 312380
Summary: When we backtranslate expressions, we can't use the predicateinfo, since we are evaluating them in a different context.
Reviewers: davide, mcrosier
Subscribers: sanjoy, Prazek, llvm-commits
Differential Revision: https://reviews.llvm.org/D37174
llvm-svn: 312352
Summary:
LoopVectorizer is creating casts between vec<ptr> and vec<float> types
on ARM when compiling OpenCV. Since, tIs is illegal to directly cast a
floating point type to a pointer type even if the types have same size
causing a crash. Fix the crash using a two-step casting by bitcasting
to integer and integer to pointer/float.
Fixes PR33804.
Reviewers: mkuper, Ayal, dlj, rengolin, srhines
Reviewed By: rengolin
Subscribers: aemerson, kristof.beyls, mkazantsev, Meinersbur, rengolin, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35498
llvm-svn: 312331
This patch provides such debug information for integer
variables whose type is shrinked to bool by providing
dwarf expression which returns either constant initial
value or other value.
Patch by Nikola Prica.
Differential Revision: https://reviews.llvm.org/D35994
llvm-svn: 312318
comparisons into memcmp.
Thanks to recent improvements in the LLVM codegen, the memcmp is typically
inlined as a chain of efficient hardware comparisons.
This typically benefits C++ member or nonmember operator==().
For now this is disabled by default until:
- https://bugs.llvm.org/show_bug.cgi?id=33329 is complete
- Benchmarks show that this is always useful.
Differential Revision:
https://reviews.llvm.org/D33987
llvm-svn: 312315
The BasicBlock passed to FindPredecessorRetainWithSafePath should be the
parent block of Autorelease. This fixes a crash that occurs in
FindDependencies when StartInst is not in StartBB.
rdar://problem/33866381
llvm-svn: 312266
Recurse instead of returning on the first found optimization. Also, return early in the caller
instead of continuing because that allows another round of simplification before we might
potentially lose undef information from a shuffle mask by eliminating the shuffle.
As noted in the review, we could probably do better and be more efficient by moving all of
demanded elements into a separate pass, but this is yet another quick fix to instcombine.
Differential Revision: https://reviews.llvm.org/D37236
llvm-svn: 312248
Current implementation of parseLoopStructure interprets the latch comparison as a
comarison against `iv.next`. If the actual comparison is made against the `iv` current value
then the loop may be rejected, because this misinterpretation leads to incorrect evaluation
of the latch start value.
This patch teaches the IRCE to distinguish this kind of loops and perform the optimization
for them. Now we use `IndVarBase` variable which can be either next or current value of the
induction variable (previously we used `IndVarNext` which was always the value on next iteration).
Differential Revision: https://reviews.llvm.org/D36215
llvm-svn: 312221
Renaming as a preparation step to generalizing IRCE for comparison not only against
the next value of an indvar, but also against the current.
Differential Revision: https://reviews.llvm.org/D36509
llvm-svn: 312215
This code is double-dead:
1. We simplify all selects with constant true/false condition in InstSimplify.
I've minimized/moved the tests to show that works as expected.
2. All remaining vector selects with a constant condition are canonicalized to
shufflevector, so we really can't see this pattern.
llvm-svn: 312123
Summary:
If the first insertelement instruction has multiple users and inserts at
position 0, we can re-use this instruction when folding a chain of
insertelement instructions. As we need to generate the first
insertelement instruction anyways, this should be a strict improvement.
We could get rid of the restriction of inserting at position 0 by
creating a different shufflemask, but it is probably worth to keep the
first insertelement instruction with position 0, as this is easier to do
efficiently than at other positions I think.
Reviewers: grosser, mkuper, fpetrogalli, efriedma
Reviewed By: fpetrogalli
Subscribers: gareevroman, llvm-commits
Differential Revision: https://reviews.llvm.org/D37064
llvm-svn: 312110
Summary:
When jumptable encoding does not match target code encoding (arm vs
thumb), a veneer is inserted by the linker. We can not avoid this
in all cases, because entries within one jumptable must have the same
encoding, but we can make it less common by selecting the jumptable
encoding to match the majority of its targets.
This change only covers FullLTO, and not ThinLTO.
Reviewers: pcc
Subscribers: aemerson, mehdi_amini, javed.absar, kristof.beyls, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D37171
llvm-svn: 312054
Summary:
Cross-DSO CFI needs all __cfi_check exports to use the same encoding
(ARM vs Thumb).
Reviewers: pcc
Subscribers: aemerson, srhines, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37243
llvm-svn: 312052
This is to fix PR34257. rL309059 takes an early return when FindLIVLoopCondition
fails to find a loop invariant condition. This is wrong and it will disable loop
unswitch for select. The patch fixes the bug.
Differential Revision: https://reviews.llvm.org/D36985
llvm-svn: 312045
Summary:
If SimplifyCFG pass is able to merge conditional stores into single one,
it loses the alignment. This may lead to incorrect codegen. Patch
sets the alignment of the new instruction if it is set in the original
one.
Reviewers: jmolloy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36841
llvm-svn: 312030
This patch adds splat support to transformZExtICmp. The test cases are vector versions of tests that failed when commenting out parts of the existing scalar code.
One test didn't vectorize optimize properly due to another bug so a TODO has been added.
Differential Revision: https://reviews.llvm.org/D37253
llvm-svn: 312023
Summary:
Remove some code that was no longer needed. The first FIXME is
stale since we long ago started using the index to drive importing,
rather than doing force importing based on linkage type. And
now with r309278, we no longer import any aliases.
Reviewers: dblaikie
Subscribers: inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D37266
llvm-svn: 312019
Summary: We originally assume that in pgo-icp, the promoted direct call will never be null after strip point casts. However, stripPointerCasts is so smart that it could possibly return the value of the function call if it knows that the return value is always an argument. In this case, the returned value cannot cast to Instruction. In this patch, null check is added to ensure null pointer will not be accessed.
Reviewers: tejohnson, xur, davidxl, djasper
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D37252
llvm-svn: 312005
As suggested in D37121, here's a wrapper for removeFromParent() + insertAfter(),
but implemented using moveBefore() for symmetry/efficiency.
Differential Revision: https://reviews.llvm.org/D37239
llvm-svn: 312001
When LSR processes code like
int accumulator = 0;
for (int i = 0; i < N; i++) {
accummulator += i;
use((double) accummulator);
}
It may decide to replace integer `accumulator` with a double Shadow IV to get rid
of casts. The problem with that is that the `accumulator`'s value may overflow.
Starting from this moment, the behavior of integer and double accumulators
will differ.
This patch strenghtens up the conditions of Shadow IV mechanism applicability.
We only allow it for IVs that are proved to be `AddRec`s with `nsw`/`nuw` flag.
Differential Revision: https://reviews.llvm.org/D37209
llvm-svn: 311986
This was pretty close to working already. While I was here I went ahead and passed the ICmpInst pointer from the caller instead of doing a dyn_cast that can never fail.
Differential Revision: https://reviews.llvm.org/D37237
llvm-svn: 311960
In r311742 we marked the PCs array as used so it wouldn't be dead
stripped, but left the guard and 8-bit counters arrays alone since
these are referenced by the coverage instrumentation. This doesn't
quite work if we want the indices of the PCs array to match the other
arrays though, since elements can still end up being dead and
disappear.
Instead, we mark all three of these arrays as used so that they'll be
consistent with one another.
llvm-svn: 311959
Be more consistent with CreateFunctionLocalArrayInSection in the API
of CreatePCArray, and assign the member variable in the caller like we
do for the guard and 8-bit counter arrays.
This also tweaks the order of method declarations to match the order
of definitions in the file.
llvm-svn: 311955
We were handling some vectors in foldSelectIntoOp, but not if the operand of the bin op was any kind of vector constant. This patch fixes it to treat vector splats the same as scalars.
Differential Revision: https://reviews.llvm.org/D37232
llvm-svn: 311940
When peeling kicks in, it updates the loop preheader.
Later, a successful full unroll of the loop needs to update a PHI
which i-th argument comes from the loop preheader, so it'd better look
at the correct block. Fixes PR33437.
Differential Revision: https://reviews.llvm.org/D37153
llvm-svn: 311922
Summary:
Currently, a phi node is created in the normal destination to unify the return values from promoted calls and the original indirect call. This patch makes this phi node to be created only when the return value has uses.
This patch is necessary to generate valid code, as compiler crashes with the attached test case without this patch. Without this patch, an illegal phi node that has no incoming value from `entry`/`catch` is created in `cleanup` block.
I think existing implementation is good as far as there is at least one use of the original indirect call. `insertCallRetPHI` creates a new phi node in the normal destination block only when the original indirect call dominates its use and the normal destination block. Otherwise, `fixupPHINodeForNormalDest` will handle the unification of return values naturally without creating a new phi node. However, if there's no use, `insertCallRetPHI` still creates a new phi node even when the original indirect call does not dominate the normal destination block, because `getCallRetPHINode` returns false.
Reviewers: xur, davidxl, danielcdh
Reviewed By: xur
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37176
llvm-svn: 311906
Original commit r311077 of D32871 was reverted in r311304 due to failures
reported in PR34248.
This recommit fixes PR34248 by restricting the packing of predicated scalars
into vectors only when vectorizing, avoiding doing so when unrolling w/o
vectorizing. Added a test derived from the reproducer of PR34248.
llvm-svn: 311849
Prior to this change (and after r311371), we computed it
unconditionally, causin gsevere compile time regressions (in some
cases, 5 to 10x).
llvm-svn: 311804
Just create an all 1s demanded mask and continue recursing like normal. The recursive calls should be able to handle an all 1s mask and do the right thing.
The only time we should care about knowing whether the upper bit was demanded is when we need to know if we should clear the NSW/NUW flags.
Now that we have a consistent path through the code for all cases, use KnownBits::computeForAddSub to compute the known bits at the end since we already have the LHS and RHS.
My larger goal here is to move the code that turns add into xor if only 1 bit is demanded and no bits below it are non-zero from InstCombiner::OptAndOp to here. This will allow it to be more general instead of just looking for 'add' and 'and' with constant RHS.
Differential Revision: https://reviews.llvm.org/D36486
llvm-svn: 311789
Summary:
SimplifyIndVar may introduce zext instructions to widen arguments of the
loop exit check. They should not prevent us from splitting the loop at
the induction variable, but maybe the check should be more conservative,
e.g. making sure it only extends arguments used by a comparison?
Reviewers: karthikthecool, mcrosier, mzolotukhin
Reviewed By: mcrosier
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D34879
llvm-svn: 311783
There are cases where AShr have better chance to be optimized than LShr, especially when the demanded bits are not known to be Zero, and also known to be similar to the sign bit.
Differential Revision: https://reviews.llvm.org/D36936
llvm-svn: 311773
Summary:
Add musttail to any resume instructions that is immediately followed by a
suspend (i.e. ret). We do this even in -O0 to support guaranteed tail call
for symmetrical coroutine control transfer (C++ Coroutines TS extension).
This transformation is done only in the resume part of the coroutine that has
identical signature and calling convention as the coro.resume call.
Reviewers: GorNishanov
Reviewed By: GorNishanov
Subscribers: EricWF, majnemer, llvm-commits
Differential Revision: https://reviews.llvm.org/D37125
llvm-svn: 311751
There are 3 small independent changes here:
1. Account for multiple uses in the pattern matching: avoid the transform if it increases the instruction count.
2. Add a missing fold for the case where the numerator is the constant: http://rise4fun.com/Alive/E2p
3. Enable all folds for vector types.
There's still one more potential change - use "shouldChangeType()" to keep from transforming to an illegal integer type.
Differential Revision: https://reviews.llvm.org/D36988
llvm-svn: 311726
Summary:
When reassociating an expression, do not drop the instruction's
original debug location in case the replacement location is
missing.
The debug location must at least not be dropped for inlinable
callsites of debug-info-bearing functions in debug-info-bearing
functions. Failing to do so would result in an "inlinable function "
"call in a function with debug info must have a !dbg location"
error in the verifier.
As preserving the original debug location is not expected
to result in overly jumpy debug line information, it is
preserved for all other cases too.
This fixes PR34231:
https://bugs.llvm.org/show_bug.cgi?id=34231
Original patch by David Stenberg
Reviewers: davide, craig.topper, mcrosier, dblaikie, aprantl
Reviewed By: davide, aprantl
Subscribers: aprantl
Differential Revision: https://reviews.llvm.org/D36865
llvm-svn: 311642
Current PGO only annotates the edge weight for branch and switch instructions
with profile counts. We should also annotate the indirectbr instruction as
all the information is there. This patch enables the annotating for indirectbr
instructions. Also uses this annotation in branch probability analysis.
Differential Revision: https://reviews.llvm.org/D37074
llvm-svn: 311604
The lowering isn't really an optimization, so optnone shouldn't make a
difference. ARM relies on the pass running when using "-mthread-model
single", because in that mode, it doesn't run AtomicExpand. See bug for
more details.
Differential Revision: https://reviews.llvm.org/D37040
llvm-svn: 311565
Summary:
If a coroutine outer calls another coroutine inner and the inner coroutine body is inlined into the outer, coro.begin from the inner coroutine should be considered for spilling if accessed across suspends.
Prior to this change, coroutine frame building code was not considering any coro.begins for spilling.
With this change, we only ignore coro.begin for the current coroutine, but, any coro.begins that were inlined into the current coroutine are eligible for spills.
Fixes PR34267
Reviewers: GorNishanov
Subscribers: qcolombet, llvm-commits, EricWF
Differential Revision: https://reviews.llvm.org/D37062
llvm-svn: 311556
..if the resulting subtract will be broken up later. This can cause us to get
into an infinite loop.
x + (-5.0 * y) -> x - (5.0 * y) ; Canonicalize neg const
x - (5.0 * y) -> x + (0 - (5.0 * y)) ; Break up subtract
x + (0 - (5.0 * y)) -> x + (-5.0 * y) ; Replace 0-X with X*-1.
PR34078
llvm-svn: 311554
InstCombine folds instructions with irrelevant conditions to undef.
This, as Nuno confirmed is a bug.
(see https://bugs.llvm.org/show_bug.cgi?id=33409#c1 )
Given the original motivation for the change is that of removing an
USE, we now fold to false instead (which reaches the same goal
without undesired side effects).
Fixes PR33409.
Differential Revision: https://reviews.llvm.org/D36975
llvm-svn: 311540
Looks like for 'and' and 'or' we end up performing at least some of the transformations this is bocking in a round about way anyway.
For 'and sext(cmp1), sext(cmp2) we end up later turning it into 'select cmp1, sext(cmp2), 0'. Then we optimize that back to sext (and cmp1, cmp2). This is the same result we would have gotten if shouldOptimizeCast hadn't blocked it. We do something analogous for 'or'.
With this patch we allow that transformation to happen directly in foldCastedBitwiseLogic. And we now support the same thing for 'xor'. This is definitely opening up many other cases, but since we already went around it for some cases hopefully it's ok.
Differential Revision: https://reviews.llvm.org/D36213
llvm-svn: 311508
We can't reuse the llvm.assume instruction's bitcast because it may not
dominate every user of the vtable pointer.
Differential Revision: https://reviews.llvm.org/D36994
llvm-svn: 311491
Summary:
Use the initialexec TLS type and eliminate calls to the TLS
wrapper. Fixes the sanitizer-x86_64-linux-fuzzer bot failure.
Reviewers: vitalybuka, kcc
Reviewed By: kcc
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37026
llvm-svn: 311490
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.
This is reapplies the original patch r311057 that was reverted in r311381.
The previous version wasn't using the batch update api for updating dominators,
which in vary rare cases caused assertion failures.
This also fixes PR34258.
Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki
Reviewed By: davide
Subscribers: grandinj, zhendongsu, llvm-commits, david2050
Differential Revision: https://reviews.llvm.org/D35869
llvm-svn: 311467
I don't think there's any reason to have them scattered about and on all 4 operands. We already have an early check that both compares must be the same type. And within a given compare the LHS and RHS must have the same type. Beyond that I don't think there's anyway this function returns anything valid for pointer types. So let's just return early and be done with it.
Differential Revision: https://reviews.llvm.org/D36561
llvm-svn: 311383
Currently, the inline cost model will bail once the inline cost exceeds the
inline threshold in order to avoid unnecessary compile-time. However, when
debugging it is useful to compute the full cost, so this command line option
is added to override the default behavior.
I took over this work from Chad Rosier (mcrosier@codeaurora.org).
Differential Revision: https://reviews.llvm.org/D35850
llvm-svn: 311371
The 1st try was reverted because it could inf-loop by creating a dead instruction.
Fixed that to not happen and added a test case to verify.
Original commit message:
Try to fold:
memcmp(X, C, ConstantLength) == 0 --> load X == *C
Without this change, we're unnecessarily checking the alignment of the constant data,
so we miss the transform in the first 2 tests in the patch.
I noted this shortcoming of LibCallSimpifier in one of the recent CGP memcmp expansion
patches. This doesn't help the example in:
https://bugs.llvm.org/show_bug.cgi?id=34032#c13
...directly, but it's worth short-circuiting more of these simple cases since we're
already trying to do that.
The benefit of transforming to load+cmp is that existing IR analysis/transforms may
further simplify that code. For example, if the load of the variable is common to
multiple memcmp calls, CSE can remove the duplicate instructions.
Differential Revision: https://reviews.llvm.org/D36922
llvm-svn: 311366
This is similar to what was already done in foldSelectICmpAndOr. Ultimately I'd like to see if we can call foldSelectICmpAnd from foldSelectIntoOp if we detect a power of 2 constant. This would allow us to remove foldSelectICmpAndOr entirely.
Differential Revision: https://reviews.llvm.org/D36498
llvm-svn: 311362
Summary:
This updates the Inliner to only add a single Optimization
Remark when Inlining, rather than an Analysis Remark and an
Optimization Remark.
Fixes https://bugs.llvm.org/show_bug.cgi?id=33786
Reviewers: anemet, davidxl, chandlerc
Reviewed By: anemet
Subscribers: haicheng, fhahn, mehdi_amini, dblaikie, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D36054
llvm-svn: 311349
Summary:
If the bitsToClear from the LHS of an 'and' comes back non-zero, but all of those bits are known zero on the RHS, we can reset bitsToClear.
Without this, the 'or' in the modified test case blocks the transform because it has non-zero bits in its RHS in those bits.
Reviewers: spatel, majnemer, davide
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36944
llvm-svn: 311343
Try to fold:
memcmp(X, C, ConstantLength) == 0 --> load X == *C
Without this change, we're unnecessarily checking the alignment of the constant data,
so we miss the transform in the first 2 tests in the patch.
I noted this shortcoming of LibCallSimpifier in one of the recent CGP memcmp expansion
patches. This doesn't help the example in:
https://bugs.llvm.org/show_bug.cgi?id=34032#c13
...directly, but it's worth short-circuiting more of these simple cases since we're
already trying to do that.
The benefit of transforming to load+cmp is that existing IR analysis/transforms may
further simplify that code. For example, if the load of the variable is common to
multiple memcmp calls, CSE can remove the duplicate instructions.
Differential Revision: https://reviews.llvm.org/D36922
llvm-svn: 311333
Added a separate metadata to indicate when the loop
has already been vectorized instead of setting width and count to 1.
Patch written by Divya Shanmughan and Aditya Kumar
Differential Revision: https://reviews.llvm.org/D36220
llvm-svn: 311281
Summary:
This updates the Inliner to only add a single Optimization
Remark when Inlining, rather than an Analysis Remark and an
Optimization Remark.
Fixes https://bugs.llvm.org/show_bug.cgi?id=33786
Reviewers: anemet, davidxl, chandlerc
Reviewed By: anemet
Subscribers: haicheng, fhahn, mehdi_amini, dblaikie, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D36054
llvm-svn: 311273
Summary:
Follow up to fix in r311023, which fixed the case where the combined
index is written to disk. The same samplePGO logic exists for the
in-memory index when computing imports, so we need to filter out
GlobalVariable summaries there too.
Reviewers: davidxl
Subscribers: inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D36919
llvm-svn: 311254
a function into itself.
We tried to fix this before in r306495 but that got reverted as the
assert was actually hit.
This fixes the original bug (which we seem to have lost track of with
the revert) by blocking a second remapping when the function being
inlined is also the caller and the remapping could succeed but
erroneously.
The included test case would actually load from an inlined copy of the
alloca before this change, failing to load the stored value and
miscompiling.
Many thanks to Richard Smith for diagnosing a user miscompile to this
bug, and to Kyle for the first attempt and initial analysis and David Li
for remembering the issue and how to fix it and suggesting the patch.
I'm just stitching it together and landing it. =]
llvm-svn: 311229
Clamp function was too optimistic when choosing signed or unsigned min/max function for calculations.
In fact, `!IsSignedPredicate` guarantees us that `Smallest` and `Greatest` can be compared safely using unsigned
predicates, but we did not check this for `S` which can in theory be negative.
This patch makes Clamp use signed min/max for cases when it fails to prove `S` being non-negative,
and it adds a test where such situation may lead to incorrect conditions calculation.
Differential Revision: https://reviews.llvm.org/D36873
llvm-svn: 311205
Summary:
Memcpy intrinsics have size argument of any integer type, like i32 or i64.
Fixed size type along with its value when cloning the intrinsic.
Reviewers: davidxl, xur
Reviewed By: davidxl
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D36844
llvm-svn: 311188
Summary:
Augment SanitizerCoverage to insert maximum stack depth tracing for
use by libFuzzer. The new instrumentation is enabled by the flag
-fsanitize-coverage=stack-depth and is compatible with the existing
trace-pc-guard coverage. The user must also declare the following
global variable in their code:
thread_local uintptr_t __sancov_lowest_stack
https://bugs.llvm.org/show_bug.cgi?id=33857
Reviewers: vitalybuka, kcc
Reviewed By: vitalybuka
Subscribers: kubamracek, hiraditya, cfe-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D36839
llvm-svn: 311186
Summary: This patch teaches LoopRotate to use the new incremental API to update the DominatorTree.
Reviewers: dberlin, davide, grosser, sanjoy
Reviewed By: dberlin, davide
Subscribers: hiraditya, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D35581
llvm-svn: 311125
Summary:
This patch makes LoopUnswitch use new incremental API for updating dominators.
It also updates SplitCriticalEdge, as it is called in LoopUnswitch.
There doesn't seem to be any noticeable performance difference when bootstrapping clang with this patch.
Reviewers: dberlin, davide, sanjoy, grosser, chandlerc
Reviewed By: davide, grosser
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35528
llvm-svn: 311093
In the case where dfsan provides a custom wrapper for a function,
shadow parameters are added for each parameter of the function.
These parameters are i16s. For targets which do not consider this
a legal type, the lack of sign extension information would cause
LLVM to generate anyexts around their usage with phi variables
and calling convention logic.
Address this by introducing zero exts for each shadow parameter.
Reviewers: pcc, slthakur
Differential Revision: https://reviews.llvm.org/D33349
llvm-svn: 311087
VPlan is an ongoing effort to refactor and extend the Loop Vectorizer. This
patch introduces the VPlan model into LV and uses it to represent the vectorized
code and drive the generation of vectorized IR.
In this patch VPlan models the vectorized loop body: the vectorized control-flow
is represented using VPlan's Hierarchical CFG, with predication refactored from
being a post-vectorization-step into a vectorization planning step modeling
if-then VPRegionBlocks, and generating code inline with non-predicated code. The
vectorized code within each VPBasicBlock is represented as a sequence of
Recipes, each responsible for modelling and generating a sequence of IR
instructions. To keep the size of this commit manageable the Recipes in this
patch are coarse-grained and capture large chunks of LV's code-generation logic.
The constructed VPlans are dumped in dot format under -debug.
This commit retains current vectorizer output, except for minor instruction
reorderings; see associated modifications to lit tests.
For further details on the VPlan model see docs/Proposals/VectorizationPlan.rst
and its references.
Authors: Gil Rapaport and Ayal Zaks
Differential Revision: https://reviews.llvm.org/D32871
llvm-svn: 311077
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.
I didn't notice any performance impact when bootstrapping clang with this patch.
The patch was originally committed in r311039 and reverted in r311049.
This revision fixes the problem with not adding a dependency on the
DominatorTreeWrapperPass for the LegacyPassManager.
Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki
Reviewed By: davide
Subscribers: grandinj, zhendongsu, llvm-commits, david2050
Differential Revision: https://reviews.llvm.org/D35869
llvm-svn: 311057
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.
I didn't notice any performance impact when bootstrapping clang with this patch.
Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki
Reviewed By: davide
Subscribers: grandinj, zhendongsu, llvm-commits, david2050
Differential Revision: https://reviews.llvm.org/D35869
llvm-svn: 311039
Summary:
Mark LoopDataPrefetch and AArch64FalkorHWPFFix passes as preserving
ScalarEvolution since they do not alter loop structure and should not
alter any SCEV values (though LoopDataPrefetch may introduce new
instructions that won't have cached SCEV values yet).
This can result in slight code differences, mainly w.r.t. nsw/nuw flags
on SCEVs, since these are computed somewhat lazily when a zext/sext
instruction is encountered. As a result, passes after the modified
passes may see SCEVs with more nsw/nuw flags present.
Reviewers: sanjoy, anemet
Subscribers: aemerson, rengolin, mzolotukhin, javed.absar, kristof.beyls, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D36716
llvm-svn: 311032
To clear assumptions that are potentially invalid after trivialization, we need
to walk the use/def chain. Normally, the only way to reach an instruction with
an unsized type is via an instruction that has side effects (or otherwise will
demand its input bits). That would stop the walk. However, if we have a
readnone function that returns an unsized type (e.g., void), we must avoid
asking for the demanded bits of the function call's return value. A
void-returning readnone function is always dead (and so we can stop walking the
use/def chain here), but the check is necessary to avoid asserting.
Fixes PR34211.
llvm-svn: 311014
Summary: When we move then-else code to if, we need to merge its debug info, otherwise the hoisted instruction may have inaccurate debug info attached.
Reviewers: aprantl, probinson, dblaikie, echristo, loladiro
Reviewed By: aprantl
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D36778
llvm-svn: 310985
We were only allowing ConstantInt before. This patch allows splat of ConstantInt too.
Differential Revision: https://reviews.llvm.org/D36763
llvm-svn: 310970
Narrow ops are better for bit-tracking, and in the case of vectors,
may enable better codegen.
As the trunc test shows, this can allow follow-on simplifications.
There's a block of code in visitTrunc that deals with shifted ops
with FIXME comments. It may be possible to remove some of that now,
but I want to make sure there are no problems with this step first.
http://rise4fun.com/Alive/Y3a
Name: hoist_ashr_ahead_of_sext_1
%s = sext i8 %x to i32
%r = ashr i32 %s, 3 ; shift value is < than source bit width
=>
%a = ashr i8 %x, 3
%r = sext i8 %a to i32
Name: hoist_ashr_ahead_of_sext_2
%s = sext i8 %x to i32
%r = ashr i32 %s, 8 ; shift value is >= than source bit width
=>
%a = ashr i8 %x, 7 ; so clamp this shift value
%r = sext i8 %a to i32
Name: junc_the_trunc
%a = sext i16 %v to i32
%s = ashr i32 %a, 18
%t = trunc i32 %s to i16
=>
%t = ashr i16 %v, 15
llvm-svn: 310942
Summary:
This patch teaches PostDominatorTree about infinite loops. It is built on top of D29705 by @dberlin which includes a very detailed motivation for this change.
What's new is that the patch also teaches the incremental updater how to deal with reverse-unreachable regions and how to properly maintain and verify tree roots. Before that, the incremental algorithm sometimes ended up preserving reverse-unreachable regions after updates that wouldn't appear in the tree if it was constructed from scratch on the same CFG.
This patch makes the following assumptions:
- A sequence of updates should produce the same tree as a recalculating it.
- Any sequence of the same updates should lead to the same tree.
- Siblings and roots are unordered.
The last two properties are essential to efficiently perform batch updates in the future.
When it comes to the first one, we can decide later that the consistency between freshly built tree and an updated one doesn't matter match, as there are many correct ways to pick roots in infinite loops, and to relax this assumption. That should enable us to recalculate postdominators less frequently.
This patch is pretty conservative when it comes to incremental updates on reverse-unreachable regions and ends up recalculating the whole tree in many cases. It should be possible to improve the performance in many cases, if we decide that it's important enough.
That being said, my experiments showed that reverse-unreachable are very rare in the IR emitted by clang when bootstrapping clang. Here are the statistics I collected by analyzing IR between passes and after each removePredecessor call:
```
# functions: 52283
# samples: 337609
# reverse unreachable BBs: 216022
# BBs: 247840796
Percent reverse-unreachable: 0.08716159869015269 %
Max(PercRevUnreachable) in a function: 87.58620689655172 %
# > 25 % samples: 471 ( 0.1395104988314885 % samples )
... in 145 ( 0.27733680163724345 % functions )
```
Most of the reverse-unreachable regions come from invalid IR where it wouldn't be possible to construct a PostDomTree anyway.
I would like to commit this patch in the next week in order to be able to complete the work that depends on it before the end of my internship, so please don't wait long to voice your concerns :).
Reviewers: dberlin, sanjoy, grosser, brzycki, davide, chandlerc, hfinkel
Reviewed By: dberlin
Subscribers: nhaehnle, javed.absar, kparzysz, uabelho, jlebar, hiraditya, llvm-commits, dberlin, david2050
Differential Revision: https://reviews.llvm.org/D35851
llvm-svn: 310940
Two minor savings: avoid copying the SinkAfter map and avoid moving a cast if it
is not needed.
Differential Revision: https://reviews.llvm.org/D36408
llvm-svn: 310910
This recommits r310869, with the moved files and no extra changes.
Original commit message:
This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.
I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.
I also had to make decomposeBitTest support vectors since InstSimplify needs that.
As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.
Differential Revision: https://reviews.llvm.org/D36593
llvm-svn: 310889
Failed to add the two files that moved. And then added an extra change I didn't mean to while trying to fix that. Reverting everything.
llvm-svn: 310873
This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.
I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.
I also had to make decomposeBitTest support vectors since InstSimplify needs that.
As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.
Differential Revision: https://reviews.llvm.org/D36593
llvm-svn: 310869
This change let us schedule a bundle with different opcodes in it, for example : [ load, add, add, add ]
Reviewers: mkuper, RKSimon, ABataev, mzolotukhin, spatel, filcab
Subscribers: llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D36518
llvm-svn: 310847
The assert was added with r310779 and is usually correct,
but as the test shows, not always. The 'volatile' on the
load is needed to expose the faulty path because without
it, DemandedBits would return that the load is just dead
rather than not demanded, and so we wouldn't hit the
bogus assert.
Also, since the lambda is just a single-line now, get rid
of it and inline the DB.isAllOnesValue() calls.
This should fix (prevent execution of a faulty assert):
https://bugs.llvm.org/show_bug.cgi?id=34179
llvm-svn: 310842
On some targets, the penalty of executing runtime unrolling checks
and then not the unrolled loop can be significantly detrimental to
performance. This results in the need to be more conservative with
the unroll count, keeping a trip count of 2 reduces the overhead as
well as increasing the chance of the unrolled body being executed. But
being conservative leaves performance gains on the table.
This patch enables the unrolling of the remainder loop introduced by
runtime unrolling. This can help reduce the overhead of misunrolled
loops because the cost of non-taken branches is much less than the
cost of the backedge that would normally be executed in the remainder
loop. This allows larger unroll factors to be used without suffering
performance loses with smaller iteration counts.
Differential Revision: https://reviews.llvm.org/D36309
llvm-svn: 310824
Summary:
These functions were overly complicated. The body of this function was rechecking for an And operation to find the constant, but we already knew we were looking at two Ands ORed together and the pieces are in variables. We already had earlier nearby code that checked for ConstantInts. So just inline the remaining parts into the earlier code.
Next step is to use m_APInt instead of ConstantInt.
Reviewers: spatel, efriedma, davide, majnemer
Reviewed By: spatel
Subscribers: zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D36439
llvm-svn: 310806
Updating remark API to newer OptimizationDiagnosticInfo API. This
allows remarks to show up in diagnostic yaml file, and enables use
of opt-viewer tool.
Hotness information for remarks (L505 and L751) do not display hotness
information, most likely due to profile information not being
propagated yet. Unsure if this is the desired outcome.
Patch by Tarun Rajendran.
Differential Revision: https://reviews.llvm.org/D36127
llvm-svn: 310763
This also corrects the description to match what was actually implemented. The old comment said X^(C1|C2), but it implemented X^((C1|C2)&~(C1&C2)). I believe ((C1|C2)&~(C1&C2)) is equivalent to (C1^C2).
Differential Revision: https://reviews.llvm.org/D36505
llvm-svn: 310658
We used to try to truncate the constant vector to vXi1, but if it's already i1 this would fail. Instead we now use IRBuilder::getZExtOrTrunc which should check the type and only create a trunc if needed. I believe this should trigger constant folding in the IRBuilder and ultimately do the same thing just with the additional type check.
llvm-svn: 310639
Sometimes it would be nice to stop InstCombine mid way through its combining to see the current IR. By using a debug counter we can place an upper limit on how many instructions to process.
This will also allow skipping the first X combines, but that has the potential to change later combines since earlier canonicalizations might have been skipped.
Differential Revision: https://reviews.llvm.org/D36553
llvm-svn: 310638
This make it consistent with STATISTIC which it will often appears near.
While there move one DEBUG_COUNTER instance out of an anonymous namespace. It's already declaring a static variable so the namespace is unnecessary.
llvm-svn: 310637
This implementation of SanitizerCoverage instrumentation inserts different
callbacks depending on constantness of operands:
1. If both operands are non-const, then a usual
__sanitizer_cov_trace_cmp[1248] call is inserted.
2. If exactly one operand is const, then a
__sanitizer_cov_trace_const_cmp[1248] call is inserted. The first
argument of the call is always the constant one.
3. If both operands are const, then no callback is inserted.
This separation comes useful in fuzzing when tasks like "find one operand
of the comparison in input arguments and replace it with the other one"
have to be done. The new instrumentation allows us to not waste time on
searching the constant operands in the input.
Patch by Victor Chibotaru.
llvm-svn: 310600
I couldn't find any smaller folds to help the cases in:
https://bugs.llvm.org/show_bug.cgi?id=34046
after:
rL310141
The truncated rotate-by-variable patterns elude all of the existing transforms because
of multiple uses and knowledge about demanded bits and knownbits that doesn't exist
without the whole pattern. So we need an unfortunately large pattern match. But by
simplifying this pattern in IR, the backend is already able to generate
rolb/rolw/rorb/rorw for x86 using its existing rotate matching logic (although
there is a likely extraneous 'and' of the rotate amount).
Note that rotate-by-constant doesn't have this problem - smaller folds should already
produce the narrow IR ops.
Differential Revision: https://reviews.llvm.org/D36395
llvm-svn: 310509
Summary:
Instrumentation to copy byval arguments is now correctly inserted
after the dynamic shadow base is loaded.
Reviewers: vitalybuka, eugenis
Reviewed By: vitalybuka
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D36533
llvm-svn: 310503
isLegalAddressingMode() has recently gained the extra optional Instruction*
parameter, and therefore it can now do the job that previously only
isFoldableMemAccess() could do.
The SystemZ implementation of isLegalAddressingMode() has gained the
functionality of checking for offsets, which used to be done with
isFoldableMemAccess().
The isFoldableMemAccess() hook has been removed everywhere.
Review: Quentin Colombet, Ulrich Weigand
https://reviews.llvm.org/D35933
llvm-svn: 310463
In the recursive call to isAMCompletelyFolded(), the passed offset should be
the sum of F.BaseOffset and Fixup.Offset.
Review: Quentin Colombet.
llvm-svn: 310462
When a new phi is generated for scalarpre of an expression, the phiTranslate cache
will become stale: Before PRE, the candidate expression must not be available in a
predecessor block, and phitranslate will cache the information. After PRE, the
expression will become available in all predecessor blocks, so the related entries
in phiTranslate cache becomes stale. The patch will simply remove the stale entries
so phiTranslate can be recomputed next time.
The stale entries in phitranslate cache will not affect correctness but will cause
missing PRE opportunity for later instructions.
Differential Revision: https://reviews.llvm.org/D36124
llvm-svn: 310421
Summary: Currently, ICP checks the count against a fixed value to see if it is hot enough to be promoted. This does not work for SamplePGO because sampled count may be much smaller. This patch uses PSI to check if the count is hot enough to be promoted.
Reviewers: davidxl, tejohnson, eraman
Reviewed By: davidxl
Subscribers: sanjoy, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D36341
llvm-svn: 310416
We already support pulling through an add with constant RHS. We can do the same for subtract.
Differential Revision: https://reviews.llvm.org/D36443
llvm-svn: 310407
Summary:
When vectorizing fcmps we can trip on incorrect cast assertion when setting the
FastMathFlags after generating the vectorized FCmp.
This can happen if the FCmp can be folded to true or false directly. The fix
here is to set the FastMathFlag using the FastMathFlagBuilder *before* creating
the FCmp Instruction. This is what's done by other optimizations such as
InstCombine.
Added a test case which trips on cast assertion without this patch.
Reviewers: Ayal, mssimpso, mkuper, gilr
Reviewed by: Ayal, mssimpso
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D36244
llvm-svn: 310389
results when a loop is completely removed.
This is very hard to manifest as a visible bug. You need to arrange for
there to be a subsequent allocation of a 'Loop' object which gets the
exact same address as the one which the unroll deleted, and you need the
LoopAccessAnalysis results to be significant in the way that they're
stale. And you need a million other things to align.
But when it does, you get a deeply mysterious crash due to actually
finding a stale analysis result. This fixes the issue and tests for it
by directly checking we successfully invalidate things. I have not been
able to get *any* test case to reliably trigger this. Changes to LLVM
itself caused the only test case I ever had to cease to crash.
I've looked pretty extensively at less brittle ways of fixing this and
they are actually very, very hard to do. This is a somewhat strange and
unusual case as we have a pass which is deleting an IR unit, but is not
running within that IR unit's pass framework (which is what handles this
cleanly for the normal loop unroll). And where there isn't a definitive
way to clear *all* of the stale cache entries. And where the pass *is*
updating the core analysis that provides the IR units!
For example, we don't have any of these problems with Function analyses
because it is easy to clear out function analyses when the functions
themselves may have been deleted -- we clear an entire module's worth!
But that is too heavy of a hammer down here in the LoopAnalysisManager
layer.
A better long-term solution IMO is to require that AnalysisManager's
make their keys durable to this kind of thing. Specifically, when
caching an analysis for one IR unit that is conceptually "owned" by
a higher level IR unit, the AnalysisManager should incorporate this into
its data structures so that we can reliably clear these results without
having to teach each and every pass to do so manually as we do here. But
that is a change for another day as it will be a fairly invasive change
to the AnalysisManager infrastructure. Until then, this fortunately
seems to be quite rare.
llvm-svn: 310333
The root cause of reverting was fixed - PR33514.
Summary:
The patch makes instruction count the highest priority for
LSR solution for X86 (previously registers had highest priority).
Reviewers: qcolombet
Differential Revision: http://reviews.llvm.org/D30562
From: Evgeny Stupachenko <evstupac@gmail.com>
<evgeny.v.stupachenko@intel.com>
llvm-svn: 310289
Note the original code I deleted incorrectly listed this as (X | C1) & C2 --> (X & C2^(C1&C2)) | C1 Which is only valid if C1 is a subset of C2. This relied on SimplifyDemandedBits to remove any extra bits from C1 before we got to that code.
My new implementation avoids relying on that behavior so that it can be naively verified with alive.
Differential Revision: https://reviews.llvm.org/D36384
llvm-svn: 310272
Patch tries to improve two-pass vectorization analysis, existing in SLP vectorizer. What it does:
1. Defines key nodes, that are the vectorization roots. Previously vectorization started if StoreInst or ReturnInst is found. For now, the vectorization started for all Instructions with no users and void types (Terminators, StoreInst) + CallInsts.
2. CmpInsts, InsertElementInsts and InsertValueInsts are stored in the
array. This array is processed only after the vectorization of the
first-after-these instructions key node is finished. Vectorization goes
in reverse order to try to vectorize as much code as possible.
Reviewers: mzolotukhin, Ayal, mkuper, gilr, hfinkel, RKSimon
Subscribers: ashahid, anemet, RKSimon, mssimpso, llvm-commits
Differential Revision: https://reviews.llvm.org/D29826
llvm-svn: 310260
Summary:
Patch tries to improve two-pass vectorization analysis, existing in SLP vectorizer. What it does:
1. Defines key nodes, that are the vectorization roots. Previously vectorization started if StoreInst or ReturnInst is found. For now, the vectorization started for all Instructions with no users and void types (Terminators, StoreInst) + CallInsts.
2. CmpInsts, InsertElementInsts and InsertValueInsts are stored in the array. This array is processed only after the vectorization of the first-after-these instructions key node is finished. Vectorization goes in reverse order to try to vectorize as much code as possible.
Reviewers: mzolotukhin, Ayal, mkuper, gilr, hfinkel, RKSimon
Subscribers: ashahid, anemet, RKSimon, mssimpso, llvm-commits
Differential Revision: https://reviews.llvm.org/D29826
llvm-svn: 310255
While here, rename `i` to `Rank` as the latter is more
self-explanatory (and this code also uses `I` two lines below to
identify an Instruction).
llvm-svn: 310238
Unfortunately, it looks like there's some other missed optimizations in the generated code for some of these cases. I'll try to look at some of those next.
llvm-svn: 310184
Previously we were always trying to emit the zext or truncate before any shift. This meant if the 'and' mask was larger than the size of the truncate we would skip the transformation.
Now we shift the result of the and right first leaving the bit within the range of the truncate.
This matches what we are doing in foldSelectICmpAndOr for the same problem.
llvm-svn: 310159
Summary:
The bug was uncovered after fix of PR23384 (part 3 of 3).
The patch restricts pointer multiplication in SCEV computaion for ICmpZero.
Reviewers: qcolombet
Differential Revision: http://reviews.llvm.org/D36170
From: Evgeny Stupachenko <evstupac@gmail.com>
<evgeny.v.stupachenko@intel.com>
llvm-svn: 310092
The frontend may have requested a higher alignment for any reason, and
downstream optimizations may already have taken advantage of it. We
should keep the same alignment when moving the allocation from the
parameter area to the local variable area.
Fixes PR34038
llvm-svn: 310071
Summary:
The (not (sext)) case is really (xor (sext), -1) which should have been simplified to (sext (xor, 1)) before we got here. So we shouldn't need to handle it.
With that taken care of we only need to two cases so don't need the swap anymore. This makes us in sync with the equivalent code in visitOr so inline this to match.
Reviewers: spatel, eli.friedman, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36240
llvm-svn: 310063
Name: narrow_shift
Pre: C1 < 8
%zx = zext i8 %x to i32
%l = lshr i32 %zx, C1
=>
%narrowC = trunc i32 C1 to i8
%ns = lshr i8 %x, %narrowC
%l = zext i8 %ns to i32
http://rise4fun.com/Alive/jIV
This isn't directly applicable to PR34046 as written, but we
need to have more narrowing folds like this to be sure that
rotate patterns are recognized.
llvm-svn: 310060
Summary:
This fixes PR31777.
If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.
In the future we should also support vectors of integers. And maybe
float/double if we can.
Reviewers: hfinkel, junbuml, jfb, RKSimon, bkramer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30703
llvm-svn: 310055
Summary:
This commit allows matchSelectPattern to recognize clamp of float
arguments in the presence of FMF the same way as already done for
integers.
This case is a little different though. With integers, given the
min/max pattern is recognized, DAGBuilder starts selecting MIN/MAX
"automatically". That is not the case for float, because for them only
full FMINNAN/FMINNUM/FMAXNAN/FMAXNUM ISD nodes exist and they do care
about NaNs. On the other hand, some backends (e.g. X86) have only
FMIN/FMAX nodes that do not care about NaNS and the former NAN/NUM
nodes are illegal thus selection is not happening. So I decided to do
such kind of transformation in IR (InstCombiner) instead of
complicating the logic in the backend.
Reviewers: spatel, jmolloy, majnemer, efriedma, craig.topper
Reviewed By: efriedma
Subscribers: hiraditya, javed.absar, n.bozhenov, llvm-commits
Patch by Andrei Elovikov <andrei.elovikov@intel.com>
Differential Revision: https://reviews.llvm.org/D33186
llvm-svn: 310054
This is similar to what we are doing in "regular" SROA and creates
DW_OP_LLVM_fragment operations to describe the resulting variables.
rdar://problem/33654891
llvm-svn: 310014
Summary:
Detect when the working set size of a profiled application is huge,
by comparing the number of counts required to reach the hot percentile
in the profile summary to a large threshold*.
When the working set size is determined to be huge, disable peeling
to avoid bloating the working set further.
*Note that the selected threshold (15K) is significantly larger than the
largest working set value in SPEC cpu2006 (which is gcc at around 11K).
Reviewers: davidxl
Subscribers: mehdi_amini, mzolotukhin, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D36288
llvm-svn: 310005
Summary:
Peeling should not occur during the full unrolling invocation early
in the pipeline, but rather later with partial and runtime loop
unrolling. The later loop unrolling invocation will also eventually
utilize profile summary and branch frequency information, which
we would like to use to control peeling. And for ThinLTO we want
to delay peeling until the backend (post thin link) phase, just as
we do for most types of unrolling.
Ensure peeling doesn't occur during the full unrolling invocation
by adding a parameter to the shared implementation function, similar
to the way partial and runtime loop unrolling are disabled.
Performance results for ThinLTO suggest this has a neutral to positive
effect on some internal benchmarks.
Reviewers: chandlerc, davidxl
Subscribers: mzolotukhin, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D36258
llvm-svn: 309966
Summary:
This is largely NFC*, in preparation for utilizing ProfileSummaryInfo
and BranchFrequencyInfo analyses. In this patch I am only doing the
splitting for the New PM, but I can do the same for the legacy PM as
a follow-on if this looks good.
*Not NFC since for partial unrolling we lose the updates done to the
loop traversal (adding new sibling and child loops) - according to
Chandler this is not very useful for partial unrolling, but it also
means that the debugging flag -unroll-revisit-child-loops no longer
works for partial unrolling.
Reviewers: chandlerc
Subscribers: mehdi_amini, mzolotukhin, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D36157
llvm-svn: 309886
As far as I can tell this should be handled by foldCastedBitwiseLogic which is called later in visitXor.
Differential Revision: https://reviews.llvm.org/D36214
llvm-svn: 309882
This adds support for sext in foldLogicCastConstant. This is a prerequisite for D36214.
Differential Revision: https://reviews.llvm.org/D36234
llvm-svn: 309880
Summary:
This patch makes LoopDeletion use the incremental DominatorTree API.
We modify LoopDeletion to perform the deletion in 5 steps:
1. Create a new dummy edge from the preheader to the exit, by adding a conditional branch.
2. Inform the DomTree about the new edge.
3. Remove the conditional branch and replace it with an unconditional edge to the exit. This removes the edge to the loop header, making it unreachable.
4. Inform the DomTree about the deleted edge.
5. Remove the unreachable block from the function.
Creating the dummy conditional branch is necessary to perform incremental DomTree update.
We should consider using the batch updater when it's ready.
Reviewers: dberlin, davide, grosser, sanjoy
Reviewed By: dberlin, grosser
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35391
llvm-svn: 309850
Summary:
Currently most of the time vectors of extractelement instructions are
treated as scalars that must be gathered into vectors. But in some
cases, like when we have extractelement instructions from single vector
with different constant indeces or from 2 vectors of the same size, we
can treat this operations as shuffle of a single vector or blending of 2
vectors.
```
define <2 x i8> @g(<2 x i8> %x, <2 x i8> %y) {
%x0 = extractelement <2 x i8> %x, i32 0
%y1 = extractelement <2 x i8> %y, i32 1
%x0x0 = mul i8 %x0, %x0
%y1y1 = mul i8 %y1, %y1
%ins1 = insertelement <2 x i8> undef, i8 %x0x0, i32 0
%ins2 = insertelement <2 x i8> %ins1, i8 %y1y1, i32 1
ret <2 x i8> %ins2
}
```
can be converted to something like
```
define <2 x i8> @g(<2 x i8> %x, <2 x i8> %y) {
%1 = shufflevector <2 x i8> %x, <2 x i8> %y, <2 x i32> <i32 0, i32 3>
%2 = mul <2 x i8> %1, %1
ret <2 x i8> %2
}
```
Currently this type of conversion is considered as high cost
transformation.
Reviewers: mzolotukhin, delena, mkuper, hfinkel, RKSimon
Subscribers: ashahid, RKSimon, spatel, llvm-commits
Differential Revision: https://reviews.llvm.org/D30200
llvm-svn: 309812
infinite-inlining across multiple runs of the inliner by keeping a tiny
history of internal-to-SCC inlining decisions.
This is still a bit gross, but I don't yet have any fundamentally better
ideas and numerous people are blocked on this to use new PM and ThinLTO
together.
The core of the idea is to detect when we are about to do an inline that
has a chance of re-splitting an SCC which we have split before with
a similar inlining step. That is a critical component in the inlining
forming a cycle and so far detects all of the various cyclic patterns
I can come up with as well as the original real-world test case (which
comes from a ThinLTO build of libunwind).
I've added some tests that I think really demonstrate what is going on
here. They are essentially state machines that march the inliner through
various steps of a cycle and check that we stop when the cycle is closed
and that we actually did do inlining to form that cycle.
A lot of thanks go to Eric Christopher and Sanjoy Das for the help
understanding this issue and improving the test cases.
The biggest "yuck" here is the layering issue -- the CGSCC pass manager
is providing somewhat magical state to the inliner for it to use to make
itself converge. This isn't great, but I don't honestly have a lot of
better ideas yet and at least seems nicely isolated.
I have tested this patch, and it doesn't block *any* inlining on the
entire LLVM test suite and SPEC, so it seems sufficiently narrowly
targeted to the issue at hand.
We have come up with hypothetical issues that this patch doesn't cover,
but so far none of them are practical and we don't have a viable
solution yet that covers the hypothetical stuff, so proceeding here in
the interim. Definitely an area that we will be back and revisiting in
the future.
Differential Revision: https://reviews.llvm.org/D36188
llvm-svn: 309784
Summary:
As far as I can tell the earlier call getLimitedValue will guaranteed ShiftAmt is saturated to BitWidth-1 preventing it from ever being equal or greater than BitWidth.
At one point in the past the getLimitedValue call was only passed BitWidth not BitWidth - 1. This would have allowed the equality case to get here. And in fact this check was initially added as just BitWidth == ShiftAmt, but was changed shortly after to include > which should have never been possible.
Reviewers: spatel, majnemer, davide
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36123
llvm-svn: 309690
To the best of my knowledge -metarenamer is used in two cases:
1) obfuscate names, when e.g. they contain informations that
can't be shared.
2) Improve clarity of the textual IR for testcases.
One of the usecases if getting the output of `opt` and passing it
to the lli interpreter to run the test. If metarenamer renames
@main, lli can't find an entry point.
llvm-svn: 309657
Summary:
Adding part of the changes in D30369 (needed to make progress):
Current patch updates AliasAnalysis and MemoryLocation, but does _not_ clean up MemorySSA.
Original summary from D30369, by dberlin:
Currently, we have instructions which affect memory but have no memory
location. If you call, for example, MemoryLocation::get on a fence,
it asserts. This means things specifically have to avoid that. It
also means we end up with a copy of each API, one taking a memory
location, one not.
This starts to fix that.
We add MemoryLocation::getOrNone as a new call, and reimplement the
old asserting version in terms of it.
We make MemoryLocation optional in the (Instruction, MemoryLocation)
version of getModRefInfo, and kill the old one argument version in
favor of passing None (it had one caller). Now both can handle fences
because you can just use MemoryLocation::getOrNone on an instruction
and it will return a correct answer.
We use all this to clean up part of MemorySSA that had to handle this difference.
Note that literally every actual getModRefInfo interface we have could be made private and replaced with:
getModRefInfo(Instruction, Optional<MemoryLocation>)
and
getModRefInfo(Instruction, Optional<MemoryLocation>, Instruction, Optional<MemoryLocation>)
and delegating to the right ones, if we wanted to.
I have not attempted to do this yet.
Reviewers: dberlin, davide, dblaikie
Subscribers: sanjoy, hfinkel, chandlerc, llvm-commits
Differential Revision: https://reviews.llvm.org/D35441
llvm-svn: 309641
D33925 added a control flow simplification for -O2 --lto-O0 builds that
manually splits blocks and reassigns conditional branches but does not
correctly update phi nodes. If the else case being branched to had
incoming phi nodes the control-flow simplification would leave phi nodes
in that BB with an unhandled predecessor.
Patch by Vlad Tsyrklevich!
Differential Revision: https://reviews.llvm.org/D36012
llvm-svn: 309621
This intrinsic clears the upper bits starting at a specified index. If the index is a constant we can do some simplifications.
This could be in InstSimplify, but we don't handle any target specific intrinsics there today.
Differential Revision: https://reviews.llvm.org/D36069
llvm-svn: 309604
This patch adds simplification support for the BEXTR/BEXTRI intrinsics to match gcc. This only supports cases that fold to 0 or can be fully constant folded. Theoretically we could support converting to AND if the shift part is unused or to only a shift if the mask doesn't modify any bits after an equivalent shl. gcc doesn't do these transformations either.
I put this in InstCombine, but it could be done in InstSimplify. It would be the first target specific intrinsic in InstSimplify.
Differential Revision: https://reviews.llvm.org/D36063
llvm-svn: 309603
The Loop Vectorizer generates redundant operations when manipulating masks:
AND with true, OR with false, compare equal to true. Instead of relying on
a subsequent pass to clean them up, this patch avoids generating them.
Use null (no-mask) to represent all-one full masks, instead of a constant
all-one vector, following the convention of masked gathers and scatters.
Preparing for a follow-up VPlan patch in which these mask manipulating
operations are modeled using recipes.
Differential Revision: https://reviews.llvm.org/D35725
llvm-svn: 309558
Summary:
Since r293359, most dump() function are only defined when
`!defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)` holds. print() functions
only used by dump() functions are now unused in release builds,
generating lots of warnings. This patch only defines some print()
functions if they are used.
Reviewers: MatzeB
Reviewed By: MatzeB
Subscribers: arsenm, mzolotukhin, nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D35949
llvm-svn: 309553
Summary:
Without any information about the called function, we cannot be sure
that it is safe to interchange loops which contain function calls. For
example there could be dependences that prevent interchanging between
accesses in the called function and the loops. Even functions without any
parameters could cause problems, as they could access memory using
global pointers.
For now, I think it is only safe to interchange loops with calls marked
as readnone.
With this patch, the LLVM test suite passes with `-O3 -mllvm
-enable-loopinterchange` and LoopInterchangeProfitability::isProfitable
returning true for all loops. check-llvm and check-clang also pass when
bootstrapped in a similar fashion, although only 3 loops got
interchanged.
Reviewers: karthikthecool, blitz.opensource, hfinkel, mcrosier, mkuper
Reviewed By: mcrosier
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35489
llvm-svn: 309547
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951
llvm-svn: 309426
Summary:
After some changes in SLP vectorizer we missed some additional checks to
limit the instructions for vectorization. We should not perform analysis
of the instructions if the parent of instruction is not the same as the
parent of the first instruction in the tree or it was analyzed already.
Subscribers: mzolotukhin
Differential Revision: https://reviews.llvm.org/D34881
llvm-svn: 309425
Recommit after workaround the bug PR31652.
Three bugs fixed in previous recommits: The first one is to use CurrentBlock
instead of PREInstr's Parent as param of performScalarPREInsertion because
the Parent of a clone instruction may be uninitialized. The second one is stop
PRE when CurrentBlock to its predecessor is a backedge and an operand of CurInst
is defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available. The third one is an out-of-bound
array access in a flipped if guard.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
llvm-svn: 309397
JumpThreading claims to preserve LVI, but it doesn't preserve
the analyses which LVI holds a reference to (e.g. the Dominator).
In the current pass manager infrastructure, after JT runs, the
PM frees these analyses (including DominatorTree) but preserves
LVI.
CorrelatedValuePropagation runs immediately after and queries
a corrupted domtree, causing weird miscompiles.
This commit disables the preservation of LVI for the time being.
Eventually, we should either move LVI to a proper dependency
tracking mechanism (i.e. an analyses shouldn't hold references
to other analyses and compute them on demand if needed), or
we should teach all the passes preserving LVI to preserve the
analyses LVI depends on.
The new pass manager has a mechanism to invalidate LVI in case
one of the analyses it depends on becomes invalid, so this problem
shouldn't exist (at least not in this immediate form), but handling
of analyses holding references is still a very delicate subject.
Fixes PR33917 (and rustc).
llvm-svn: 309355
Summary: The original 3.0 hot mupltiplier is too small, and would prevent hot callsites from being inline. This patch increases the hot multilier to 10.0
Reviewers: davidxl, tejohnson
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D35969
llvm-svn: 309344
The alias support was dead code since 2011. It was last touched
in r124182, where it was reintroduced after being removed
in r110434, and since then it was gated behind a HasGlobalAliases
flag that was permanently stuck as `false`.
It is also broken. I'm not sure if it bitrotted or was just broken
in the first place because it appears to have never been tested,
but the following IR results in a crash:
define internal i32 @a(i32 %a, i32 %b) unnamed_addr {
%c = add i32 %a, %b
%d = xor i32 %a, %c
ret i32 %c
}
define internal i32 @b(i32 %a, i32 %b) unnamed_addr {
%c = add i32 %a, %b
%d = xor i32 %a, %c
ret i32 %c
}
It seems safe to remove buggy untested code that no one cared about
for seven years.
Differential Revision: https://reviews.llvm.org/D34802
llvm-svn: 309313
Summary:
Pointer difference simplifications currently happen only if input GEPs don't have other uses or their indexes are all constants, to avoid duplicating indexing arithmetic.
This patch enables cases with exactly one non-constant index among input GEPs to happen where there is no duplicated arithmetic or code size increase even if input GEPs have other uses.
For example, this patch allows "(&A[42][i]-&A[42][0])" --> "i", which didn't happen previously, if the input GEP(s) have other uses.
Reviewers: sanjoy, bkramer
Reviewed By: sanjoy
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D35499
llvm-svn: 309304
This is a module pass so for the old PM, we can't use ORE, the function
analysis pass. Instead ORE is created on the fly.
A few notes:
- isPromotionLegal is folded in the caller since we want to emit the Function
in the remark but we can only do that if the symbol table look-up succeeded.
- There was good test coverage for remarks in this pass.
- promoteIndirectCall uses ORE conditionally since it's also used from
SampleProfile which does not use ORE yet.
Fixes PR33792.
Differential Revision: https://reviews.llvm.org/D35929
llvm-svn: 309294
Summary:
It is possible for some passes to materialize a call to a libcall (ex: ldexp, exp2, etc),
but these passes will not mark the call as a gc-leaf-function. All libcalls are
actually gc-leaf-functions, so we change llvm::callsGCLeafFunction() to tell us that
available libcalls are equivalent to gc-leaf-function calls.
Reviewers: sanjoy, anna, reames
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35840
llvm-svn: 309291
Summary:
Until a more advanced version of importing can be implemented for
aliases (one that imports an alias as an available_externally definition
of the aliasee), skip the narrow subset of cases that was possible but
came at a cost: aliases of linkonce_odr functions could be imported
because the linkonce_odr function could be safely duplicated from the
source module. This came/comes at the cost of not being able to 'home'
imported linkonce functions (they had to be emitted linkonce_odr in all
the destination modules (even if they weren't used by an alias) rather
than as available_externally - causing extra object size).
Tangentially, this also was the only reason ThinLTO would emit multiple
CUs in to the resulting DWARF - which happens to be a problem for
Fission (there's a fix for this in GDB but not released yet, etc).
(actually it's not the only reason - but I'm sending a patch to fix the
other reason shortly)
There's no reason to believe this particularly narrow alias importing
was especially/meaningfully important, only that it was /possible/ to
implement in this way. When a more general solution is done, it should
still satisfy the DWARF concerns above, since the import will still be
available_externally, and thus not create extra CUs.
Since now all aliases are treated the same, I removed/simplified some
test cases since they were testing corner cases where there are no
longer any corners.
Reviewers: tejohnson, mehdi_amini
Differential Revision: https://reviews.llvm.org/D35875
llvm-svn: 309278
Summary:
This changes SimplifyLibCalls to use the new OptimizationRemarkEmitter
API.
In fact, as SimplifyLibCalls is only ever called via InstCombine,
(as far as I can tell) the OptimizationRemarkEmitter is added there,
and then passed through to SimplifyLibCalls later.
I have avoided changing any remark text.
This closes PR33787
Patch by Sam Elliott!
Reviewers: anemet, davide
Reviewed By: anemet
Subscribers: davide, mehdi_amini, eraman, fhahn, llvm-commits
Differential Revision: https://reviews.llvm.org/D35608
llvm-svn: 309158
This is a workaround for the bug described in PR31652 and
http://lists.llvm.org/pipermail/llvm-dev/2017-July/115497.html. The temporary
solution is to add a function EqualityPropUnSafe. In EqualityPropUnSafe, for
some simple patterns we can know the equality comparison may contains undef,
so we regard such comparison as unsafe and will not do loop-unswitching for
them. We also need to disable the select simplification when one of select
operand is undef and its result feeds into equality comparison.
The patch cannot clear the safety issue caused by the bug, but it can suppress
the issue from happening to some extent.
Differential Revision: https://reviews.llvm.org/D35811
llvm-svn: 309059
it when safe.
Very often the BE count is the trip count minus one, and the plus one
here should fold with that minus one. But because the BE count might in
theory be UINT_MAX or some such, adding one before we extend could in
some cases wrap to zero and break when we scale things.
This patch checks to see if it would be safe to add one because the
specific case that would cause this is guarded for prior to entering the
preheader. This should handle essentially all of the common loop idioms
coming out of C/C++ code once canonicalized by LLVM.
Before this patch, both forms of loop in the added test cases ended up
subtracting one from the size, extending it, scaling it up by 8 and then
adding 8 back onto it. This is really silly, and it turns out made it
all the way into generated code very often, so this is a surprisingly
important cleanup to do.
Many thanks to Sanjoy for showing me how to do this with SCEV.
Differential Revision: https://reviews.llvm.org/D35758
llvm-svn: 308968
Summary:
The remaining non range-based for loops do not iterate over full ranges,
so leave them as they are.
Reviewers: karthikthecool, blitz.opensource, mcrosier, mkuper, aemerson
Reviewed By: aemerson
Subscribers: aemerson, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35777
llvm-svn: 308872
Summary: Currently the ThinLTO minimized bitcode file only strip the debug info, but there is still a lot of information in the minimized bit code file that will be not used for thin linker. In this patch, most of the extra information is striped to reduce the minimized bitcode file. Now only ModuleVersion, ModuleInfo, ModuleGlobalValueSummary, ModuleHash, Symtab and Strtab are left. Now the minimized bitcode file size is reduced to 15%-30% of the debug info stripped bitcode file size.
Reviewers: danielcdh, tejohnson, pcc
Reviewed By: pcc
Subscribers: mehdi_amini, aprantl, inglorion, eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D35334
llvm-svn: 308760
Separated out the profitability from the safety analysis for multiexit
loop unrolling. Currently, this is an NFC because profitability is true
only if the unroll-runtime-multi-exit is set to true (off-by-default).
This is to ease adding the profitability heuristic up for review at
D35380.
llvm-svn: 308753
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.
In order to achieve this, the following common code changes were made:
* New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
LSR should do instruction-based addressing evaluations by calling
isLegalAddressingMode() with the Instruction pointers.
* In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
not just loads or stores.
SystemZ changes:
* isLSRCostLess() implemented with Insns first, and without ImmCost.
* New function supportedAddressingMode() that is a helper for TTI methods
looking at Instructions passed via pointers.
Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262https://reviews.llvm.org/D35049
llvm-svn: 308729
Previously we were (mis)handling jump table members with a prevailing
definition in a full LTO module and a non-prevailing definition in a
ThinLTO module by dropping type metadata on those functions entirely,
which would cause type tests involving such functions to fail.
This patch causes us to drop metadata only if we are about to replace
it with metadata from cfi.functions.
We also want to replace metadata for available_externally functions,
which can arise in the opposite scenario (prevailing ThinLTO
definition, non-prevailing full LTO definition). The simplest way
to handle that is to remove the definition; there's little value in
keeping it around at this point (i.e. after most optimization passes
have already run) and later code will try to use the function's linkage
to create an alias, which would result in invalid IR if the function
is available_externally.
Fixes PR33832.
Differential Revision: https://reviews.llvm.org/D35604
llvm-svn: 308642
Large CFGs can cause us to blow up the stack because we would have a
recursive step for each basic block in a region.
Instead, create a worklist and iterate it. This limits the stack usage
to something more manageable.
Differential Revision: https://reviews.llvm.org/D35609
llvm-svn: 308582
If OpValue is non-null, we only consider operations similar to OpValue
when intersecting.
Differential Revision: https://reviews.llvm.org/D35292
llvm-svn: 308428
Summary:
When simplifying unconditional branches from empty blocks, we pre-test if the
BB belongs to a set of loop headers and keep the block to prevent passes from
destroying canonical loop structure. However, the current algorithm fails if
the destination of the branch is a loop header. Especially when such a loop's
latch block is folded into loop header it results in additional backedges and
LoopSimplify turns it into a nested loop which prevent later optimizations
from being applied (e.g., loop unrolling and loop interleaving).
This patch augments the existing algorithm by further checking if the
destination of the branch belongs to a set of loop headers and defer
eliminating it if yes to LateSimplifyCFG.
Fixes PR33605: https://bugs.llvm.org/show_bug.cgi?id=33605
Reviewers: efriedma, mcrosier, pacxx, hsung, davidxl
Reviewed By: efriedma
Subscribers: ashutosh.nema, gberry, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D35411
llvm-svn: 308422
Generate a single test to decide if there are enough iterations to jump to the
vectorized loop, or else go to the scalar remainder loop. This test compares the
Scalar Trip Count: if STC < VF * UF go to the scalar loop. If
requiresScalarEpilogue() holds, at-least one iteration must remain scalar; the
rest can be used to form vector iterations. So in this case the test checks
instead if (STC - 1) < VF * UF by comparing STC <= VF * UF, and going to the
scalar loop if so. Otherwise the vector loop is entered for at-least one vector
iteration.
This test covers the case where incrementing the backedge-taken count will
overflow leading to an incorrect trip count of zero. In this (rare) case we will
also avoid the vector loop and jump to the scalar loop.
This patch simplifies the existing tests and effectively removes the basic-block
originally named "min.iters.checked", leaving the single test in block
"vector.ph".
Original observation and initial patch by Evgeny Stupachenko.
Differential Revision: https://reviews.llvm.org/D34150
llvm-svn: 308421
functions.
In the prior commit, we provide ordering to the LCG between functions
and library function definitions that they might begin to call through
transformations. But we still would delete these library functions from
the call graph if they became dead during inlining.
While this immediately crashed, it also exposed a loss of information.
We shouldn't remove definitions of library functions that can still
usefully participate in the LCG-powered CGSCC optimization process. If
new call edges are formed, we want to have definitions to be called.
We can still remove these functions if truly dead using global-dce, etc,
but removing them during the CGSCC walk is premature.
This fixes a crash in the new PM when optimizing some unusual libraries
that end up with "internal" lib functions such as the code in the "R"
language's libraries.
llvm-svn: 308417
Summary: Currently, when GVN creates a load and when InstCombine creates a new store for unreachable Load, the DebugLoc info gets lost.
Reviewers: dberlin, davide, aprantl
Reviewed By: aprantl
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D34639
llvm-svn: 308404
Summary:
ASan determines the stack layout from alloca instructions. Since
arguments marked as "byval" do not have an explicit alloca instruction, ASan
does not produce red zones for them. This commit produces an explicit alloca
instruction and copies the byval argument into the allocated memory so that red
zones are produced.
Submitted on behalf of @morehouse (Matt Morehouse)
Reviewers: eugenis, vitalybuka
Reviewed By: eugenis
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D34789
llvm-svn: 308387
Coverage hooks that take less-than-64-bit-integers as parameters need the
zeroext parameter attribute (http://llvm.org/docs/LangRef.html#paramattrs)
to make sure they are properly extended by the x86_64 ABI.
llvm-svn: 308296
In some particular cases eq/ne conditions can be turned into equivalent
slt/sgt conditions. This patch teaches parseLoopStructure to handle some
of these cases.
Differential Revision: https://reviews.llvm.org/D35010
llvm-svn: 308264
Rename the enum value from X86_64_Win64 to plain Win64.
The symbol exposed in the textual IR is changed from 'x86_64_win64cc'
to 'win64cc', but the numeric value is kept, keeping support for
old bitcode.
Differential Revision: https://reviews.llvm.org/D34474
llvm-svn: 308208
This reverts commit r308114 (and follow on fixes to test).
There is a linking failure in a ThinLTO bot:
http://green.lab.llvm.org/green/job/clang-stage2-configure-Rthinlto_build/3663/
(and undefined reference). It seems like it must be a second order
effect of the heuristic change I made, and may take some time to try
to reproduce locally and track down. Therefore, reverting for now.
llvm-svn: 308206
This restores r308078/r308079 with a fix for bot non-determinisim (make
sure we run llvm-lto in single threaded mode so the debug output doesn't get
interleaved).
llvm-svn: 308114
Summary:
If one side simplifies to the identity value for inner opcode, we can replace the value with just the operation that can't be simplified.
I've removed a couple now unneeded special cases in visitAnd and visitOr. There are probably other cases I missed.
Reviewers: spatel, majnemer, hfinkel, dberlin
Reviewed By: spatel
Subscribers: grandinj, llvm-commits, spatel
Differential Revision: https://reviews.llvm.org/D35451
llvm-svn: 308111
that appears to exhibit non-determinism and is flaking on the bots
pretty consistently.
r308078: [ThinLTO] Ensure we always select the same function copy to import
r308079: Require asserts in new test that uses debug flag
llvm-svn: 308095
Summary:
Check if the first eligible callee is under the instruction threshold.
Checking this on the first eligible callee ensures that we don't end
up selecting different callees to import when we invoke this routine
with different thresholds due to reaching the callee via paths that
are shallower or hotter (when there are multiple copies, i.e. with
weak or linkonce linkage). We don't want to leave the decision of which
copy to import up to the backend.
Reviewers: mehdi_amini
Subscribers: inglorion, fhahn, llvm-commits
Differential Revision: https://reviews.llvm.org/D35436
llvm-svn: 308078
Summary:
When checking for memory dependencies between calls using MemorySSA,
handle cases where the calls have no MemoryAccess associated with them
because the AA analysis being used has determined that the call does not
read/write memory.
Fixes PR33756
Reviewers: dberlin, davide
Subscribers: mcrosier, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D35317
llvm-svn: 308051
Add the following pattern to TryToUnfoldSelectInCurrBB()
bb:
%p = phi [0, %bb1], [1, %bb2], [0, %bb3], [1, %bb4], ...
%c = cmp %p, 0
%s = select %c, trueval, falseval
The Select in the above pattern will be unfolded and then jump-threaded. The
current implementation does not allow CMP in the middle of PHI and Select.
Differential Revision: https://reviews.llvm.org/D34762
llvm-svn: 308050
Summary:
DominatorTreeBase used to have IsPostDominators (bool) member to indicate if the tree is a dominator or a postdominator tree. This made it possible to switch between the two 'modes' at runtime, but it isn't used in practice anywhere.
This patch makes IsPostDominator a template argument. This way, it is easier to switch between different algorithms at compile-time based on this argument and design external utilities around it. It also makes it impossible to incidentally assign a postdominator tree to a dominator tree (and vice versa), and to further simplify template code in GenericDominatorTreeConstruction.
Reviewers: dberlin, sanjoy, davide, grosser
Reviewed By: dberlin
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35315
llvm-svn: 308040
When iterating through loop
for (int i = INT_MAX; i > 0; i--)
We fail to generate the pre-loop for it. It happens because we use the
overflown value in a comparison predicate when identifying whether or not
we need it.
In old logic, we used SLE predicate against Greatest value which exceeds all
seen values of the IV and might be overflown. Now we use the GreatestSeen
value of this IV with SLT predicate.
Also added a test that ensures that a pre-loop is generated for such loops.
Differential Revision: https://reviews.llvm.org/D35347
llvm-svn: 308001
Summary:
When we runtime unroll with multiple exit blocks, we also need to update the
immediate dominators of the immediate successors of the exit blocks.
Reviewers: reames, mkuper, mzolotukhin, apilipenko
Reviewed by: mzolotukhin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35304
llvm-svn: 307909
This is an incremental change to the promotion feature.
There are two problems with the current behavior:
1) loops with multiple exiting blocks are totally disabled
2) a counter update can only be promoted one level up in
the loop nest -- which does help much for short trip
count inner loops inside a high trip-count outer loops.
Due to this limitation, we still saw very large profile
count fluctuations from run to run for the affected loops
which are usually very hot.
This patch adds the support for promotion counters iteratively
across the loop nest. It also turns on the promotion for
loops with multiple exiting blocks (with a limit).
For single-threaded applications, the performance impact is flat
on average. For instance, dealII improves, but povray regresses.
llvm-svn: 307863
Refactored the code and separated out a function
`canSafelyUnrollMultiExitLoop` to reduce redundant checks and make it
easier to add profitability heuristics later.
Added tests to runtime unrolling to make sure that unrolling for
multi-exit loops is not done unless the option
-unroll-runtime-multi-exit is true.
llvm-svn: 307843
Where is is needed (at the end of headers that define it), be
consistent about its use.
Also fix a few header guards that I found in the process.
Differential Revision: https://reviews.llvm.org/D34916
llvm-svn: 307840
Summary:
LoopRotate manually updates the DoomTree by iterating over all predecessors of a basic block and computing the Nearest Common Dominator.
When a predecessor happens to be unreachable, `DT.findNearestCommonDominator` returns nullptr.
This patch teaches LoopRotate to handle this case and fixes [[ https://bugs.llvm.org/show_bug.cgi?id=33701 | PR33701 ]].
In the future, LoopRotate should be taught to use the new incremental API for updating the DomTree.
Reviewers: dberlin, davide, uabelho, grosser
Subscribers: efriedma, mzolotukhin
Differential Revision: https://reviews.llvm.org/D35074
llvm-svn: 307828
This normally indicates mixed CFI + non-CFI compilation, and will
result in us treating the function in the same way as a function
defined outside of the LTO unit.
Part of PR33752.
Differential Revision: https://reviews.llvm.org/D35281
llvm-svn: 307744
[GlobalOpt] Remove unreachable blocks before optimizing a function.
While the change is presumably correct, it exposes a latent bug
in DI which breaks on of the CFI checks. I'll analyze it further
and try to understand what's going on.
llvm-svn: 307729
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
This is fine as nothing in the code relies on leader and memory
leader being the same for a given congruency class. Ack'ed by
Dan.
Fixes PR33720.
llvm-svn: 307699
The loop structure for the outer loop does not contain the epilog
preheader when we try to unroll inner loop with multiple exits and
epilog code is generated. For now, we just bail out in such cases.
Added a test case that shows the problem. Without this bailout, we would
trip on assert saying LCSSA form is incorrect for outer loop.
llvm-svn: 307676
querying for analysis results on a function declaration rather than
a definition.
The only reason this worked previously is by chance -- because the way
we got alias analysis results with the legacy PM, we happened to not
compute a dominator tree and so we happened to not hit an assert even
though it didn't make any real sense. Now we bail out before trying to
compute alias analysis so that we don't hit these asserts.
llvm-svn: 307625
Summary:
As metioned in https://reviews.llvm.org/D34576, checkings in
`collectConstantCandidates` can be replaced by using
`llvm::canReplaceOperandWithVariable`.
The only special case is that `collectConstantCandidates` return false for
all `IntrinsicInst` but it is safe for us to collect constant candidates from
`IntrinsicInst`.
Reviewers: pirama, efriedma, srhines
Reviewed By: efriedma
Subscribers: llvm-commits, javed.absar
Differential Revision: https://reviews.llvm.org/D34921
llvm-svn: 307587
When unrolling under multiple exits which is under off-by-default option,
the assert that checks for VMap entry in loop exit values is too strong.
(assert if VMap entry did not exist, the value should be a
constant). However, values derived from
constants or from values outside loop, does not have a VMap entry too.
Removed the assert and added a testcase showcasing the property for
non-constant values.
llvm-svn: 307542
Summary:
This solves PR33641.
When removing a dead argument we must also handle possibly existing calls
to llvm.dbg.value that use the removed argument. Now we change the use
of the otherwise dead argument to an undef for some other pass to cleanup
later.
If the calls are left untouched, they will later on cause errors:
"function-local metadata used in wrong function"
since the ArgumentPromotion rewrites the code by creating a new function
with the wanted signature, but the metadata is not recreated so the new
function may then erroneously use metadata from the old function.
Reviewers: mstorsjo, rnk, arsenm
Reviewed By: rnk
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D34874
llvm-svn: 307521
the invalidation propagation logic from an SCC to a Function.
I wrote the infrastructure to test this but didn't actually use it in
the unit test where it was designed to be used. =[ My bad. Once
I actually added it to the test case I discovered that it also hadn't
been properly implemented, so I've implemented it. The logic in the FAM
proxy for an SCC pass to propagate invalidation follows the same ideas
as the FAM proxy for a Module pass, but the implementation is a bit
different to reflect the fact that it is forwarding just for an SCC.
However, implementing this correctly uncovered a surprising "bug" (it
was conservatively correct but relatively very expensive) in how we
handle invalidation when splitting one SCC into multiple SCCs. We did an
eager invalidation when in reality we should be deferring invaliadtion
for the *current* SCC to the CGSCC pass manager and just invaliating the
newly constructed SCCs. Otherwise we end up invalidating too much too
soon. This was exposed by the inliner test case that I've updated. Now,
we invalidate *just* the split off '(test1_f)' SCC when doing the CG
update, and then the inliner finishes and invalidates the '(test1_g,
test1_h)' SCC's analyses. The first few attempts at fixing this hit
still more bugs, but all of those are covered by existing tests. For
example, the inliner should also preserve the FAM proxy to avoid
unnecesasry invalidation, and this is safe because the CG update
routines it uses handle any necessary adjustments to the FAM proxy.
Finally, the unittests for the CGSCC pass manager needed a bunch of
updates where we weren't correctly preserving the FAM proxy because it
hadn't been fully implemented and failing to preserve it didn't matter.
Note that this doesn't yet fix the current crasher due to MemSSA finding
a stale dominator tree, but without this the fix to that crasher doesn't
really make any sense when testing because it relies on the proxy
behavior.
llvm-svn: 307487
I recently changed m_One and m_AllOnes to use Constant::isOneValue/isAllOnesValue which work on floating point values too. The original implementation looked specifically for ConstantInt scalars and splats. So I'm guessing we are accidentally trying to issue sext/zexts on floating point types now.
Hopefully I figure out how to reproduce the failure from the PR soon.
llvm-svn: 307486
The patch was reverted due to a bug. The bug was that if the IV is the 2nd operand of the icmp
instruction, then the "Pred" variable gets swapped and differs from the instruction's predicate.
In this patch we use the original predicate to do the transformation.
Also added a test case that exercises this situation.
Differentian Revision: https://reviews.llvm.org/D35107
llvm-svn: 307477
Previously the InstCombiner class contained a pointer to an IR builder that had been passed to the constructor. Sometimes this would be passed to helper functions as either a pointer or the pointer would be dereferenced to be passed by reference.
This patch makes it a reference everywhere including the InstCombiner class itself so there is more inconsistency. This a large, but mechanical patch. I've done very minimal formatting changes on it despite what clang-format wanted to do.
llvm-svn: 307451
Summary: For interative sample-pgo, if a hot call site is inlined in the profiling binary, we should inline it in before profile annotation in the backend. Before that, the compile phase first collects all GUIDs that needs to be imported and creates virtual "hot" call edge in the summary. However, "hot" is not good enough to guarantee the callsites get inlined. This patch introduces "critical" call edge, and assign much higher importing threshold for those edges.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, mehdi_amini, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D35096
llvm-svn: 307439
With the NFC refactoring in rL307417 (git SHA 987dd01), all the logic
is in place to support multiple exit/exiting blocks when prolog
remainder is generated.
This patch removed the assert that multiple exit blocks unrolling is only
supported when epilog remainder is generated.
Also, added test runs and checks with PROLOG prefix in
runtime-loop-multiple-exits.ll test cases.
llvm-svn: 307435
Summary:
This is an addon to the change rl304488 cloning fixes. (Originally rl304226 reverted rl304228 and reapplied rl304488 https://reviews.llvm.org/D33655)
rl304488 works great when DILocalVariables that comes from the inlined function has a 'unique-ed' type, but,
in the case when the variable type is distinct we will create a second DILocalVariable in the scope of the original function that was inlined.
Consider cloning of the following function:
```
define private void @f() !dbg !5 {
%1 = alloca i32, !dbg !11
call void @llvm.dbg.declare(metadata i32* %1, metadata !14, metadata !12), !dbg !18
ret void, !dbg !18
}
!14 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !17) ; came from an inlined function
!15 = distinct !DISubprogram(name: "inlined", linkageName: "inlined", scope: null, file: !6, line: 8, type: !7, isLocal: true, isDefinition: true, scopeLine: 9, isOptimized: false, unit: !0, variables: !16)
!16 = !{!14}
!17 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
```
Without this fix, when function 'f' is cloned, we will create another DILocalVariable for "inlined", due to its type being distinct.
```
define private void @f.1() !dbg !23 {
%1 = alloca i32, !dbg !26
call void @llvm.dbg.declare(metadata i32* %1, metadata !28, metadata !12), !dbg !30
ret void, !dbg !30
}
!14 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !17)
!15 = distinct !DISubprogram(name: "inlined", linkageName: "inlined", scope: null, file: !6, line: 8, type: !7, isLocal: true, isDefinition: true, scopeLine: 9, isOptimized: false, unit: !0, variables: !16)
!16 = !{!14}
!17 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
;
!28 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !29) ; OOPS second DILocalVariable
!29 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
```
Now we have two DILocalVariable for "inlined" within the same scope. This result in assert in AsmPrinter/DwarfDebug.h:131: void llvm::DbgVariable::addMMIEntry(const llvm::DbgVariable &): Assertion `V.Var == Var && "conflicting variable"' failed.
(Full example: See: https://bugs.llvm.org/show_bug.cgi?id=33492)
In this change we prevent duplication of types so that when a metadata for DILocalVariable is cloned it will get uniqued to the same metadate node as an original variable.
Reviewers: loladiro, dblaikie, aprantl, echristo
Reviewed By: loladiro
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D35106
llvm-svn: 307418
Minor refactoring to use the preexisting loop exit that's already
calculated. We do not need to recompute the loop exit in ConnectProlog.
Apart from avoiding redundant computation, this is required for
supporting multiple loop exits when Prolog remainder loops are generated.
llvm-svn: 307417
InferAddressSpaces does not check address space in collectFlatAddressExpressions,
which causes values with non flat address space put into Postorder and causes
assertion in cloneValueWithNewAddressSpace.
This patch fixes assertion in OpenCL 2.0 conformance test generic_address_space
subtest for amdgcn target.
Differential Revision: https://reviews.llvm.org/D34991
llvm-svn: 307349
Adds loop expansions for known-size and unknown-sized memcpy calls, allowing the
target to provide the operand types through TTI callbacks. The default values
for the TTI callbacks use int8 operand types and matches the existing behaviour
if they aren't overridden by the target.
Differential revision: https://reviews.llvm.org/D32536
llvm-svn: 307346
Revert "Copy arguments passed by value into explicit allocas for ASan."
Revert "[asan] Add end-to-end tests for overflows of byval arguments."
Build failure on lldb-x86_64-ubuntu-14.04-buildserver.
Test failure on clang-cmake-aarch64-42vma and sanitizer-x86_64-linux-android.
llvm-svn: 307345
ASan determines the stack layout from alloca instructions. Since
arguments marked as "byval" do not have an explicit alloca instruction, ASan
does not produce red zones for them. This commit produces an explicit alloca
instruction and copies the byval argument into the allocated memory so that red
zones are produced.
Patch by Matt Morehouse.
Differential revision: https://reviews.llvm.org/D34789
llvm-svn: 307342
Using profile information to guide consthoisting is generally helpful for
performance, so the patch turns it on by default. No compile time or perf
regression were found using spec2000 and spec2006 on x86. Some significant
improvement (>20%) was seen on internal benchmarks.
Differential Revision: https://reviews.llvm.org/D35063
llvm-svn: 307338
The patch is to adjust the strategy of frequency based consthoisting:
Previously when the candidate block has the same frequency with the existing
blocks containing a const, it will not hoist the const to the candidate block.
For that case, now we change the strategy to hoist the const if only existing
blocks have more than one block member. This is helpful for reducing code size.
Differential Revision: https://reviews.llvm.org/D35084
llvm-svn: 307328
This is the same as r304719 but for ThinLTO.
The substantial difference is that in this case we don't have
whole visibility, just the summary.
In the LTO case, when we got the resolution for the input file we
could just see if the linker told us whether a symbol was linker
redefined (using --wrap or --defsym) and switch the linkage directly
for the GV.
Here, we have the summary. So, we record that the linkage changed
from <whatever it was> to $weakany to prevent IPOs across this symbol
boundaries and actually just switch the linkage at FunctionImport time.
This patch should also fixes the lld bits (as all the scaffolding for
communicating if a symbol is linker redefined should be there & should
be the same), but I'll make sure to add some tests there as well.
Fixes PR33192.
Differential Revision: https://reviews.llvm.org/D35064
llvm-svn: 307303
Summary:
`Instruction::Switch`: only first operand can be set to a non-constant value.
`Instruction::InsertValue` both the first and the second operand can be set to a non-constant value.
`Instruction::Alloca` return true for non-static allocation.
Reviewers: efriedma
Reviewed By: efriedma
Subscribers: srhines, pirama, llvm-commits
Differential Revision: https://reviews.llvm.org/D34905
llvm-svn: 307294
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.
llvm-svn: 307292
Currently, we do not support multiple exiting blocks to the
latch exit block. However, this bailout wasn't triggered when we had a
unique exit block (which is the latch exit), with multiple exiting
blocks to that unique exit.
Moved the bailout so that it's triggered in both cases and added
testcase.
llvm-svn: 307291
Summary: In this code we got to Dom by following the predecessor link of BB. So it stands to reason that BB should also show up as a successor of Dom's terminator right? There isn't a way to have the CFG connect in only one direction is there?
Reviewers: jmolloy, davide, mcrosier
Reviewed By: mcrosier
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D35025
llvm-svn: 307276
Bswap isn't a simple operation so we need to make sure we are really removing a call to it before doing these simplifications.
For the case when both LHS and RHS are bswaps I've allowed it to be moved if either LHS or RHS has a single use since that at least allows us to move it later where it might find another bswap to combine with and it decreases the use count on the other side so maybe the other user can be optimized.
Differential Revision: https://reviews.llvm.org/D34974
llvm-svn: 307273
When the formulae search space is huge, LSR uses a series of heuristic to keep
pruning the search space until the number of possible solutions are within
certain limit.
The big hammer of the series of heuristics is NarrowSearchSpaceByPickingWinnerRegs,
which picks the register which is used by the most LSRUses and deletes the other
formulae which don't use the register. This is a effective way to prune the search
space, but quite often not a good way to keep the best solution. We saw cases before
that the heuristic pruned the best formula candidate out of search space.
To relieve the problem, we introduce a new heuristic called
NarrowSearchSpaceByFilterFormulaWithSameScaledReg. The basic idea is in order to
reduce the search space while keeping the best formula, we want to keep as many
formulae with different Scale and ScaledReg as possible. That is because the central
idea of LSR is to choose a group of loop induction variables and use those induction
variables to represent LSRUses. An induction variable candidate is often represented
by the Scale and ScaledReg in a formula. If we have more formulae with different
ScaledReg and Scale to choose, we have better opportunity to find the best solution.
That is why we believe pruning search space by only keeping the best formula with the
same Scale and ScaledReg should be more effective than PickingWinnerReg. And we use
two criteria to choose the best formula with the same Scale and ScaledReg. The first
criteria is to select the formula using less non shared registers, and the second
criteria is to select the formula with less cost got from RateFormula. The patch
implements the heuristic before NarrowSearchSpaceByPickingWinnerRegs, which is the
last resort.
Testing shows we get 1.8% and 2% on two internal benchmarks on x86. llvm nightly
testsuite performance is neutral. We also tried lsr-exp-narrow and it didn't help
on the two improved internal cases we saw.
Differential Revision: https://reviews.llvm.org/D34583
llvm-svn: 307269
It seems that the patch was reverted by mistake. Clang testing showed failure of the
MathExtras.SaturatingMultiply test, however I was unable to reproduce the issue on the
fresh code base and was able to confirm that the transformation introduced by the change
does not happen in the said test. This gives a strong confidence that the actual reason of
the failure of the initial patch was somewhere else, and that problem now seems to be
fixed. Re-submitting the change to confirm that.
llvm-svn: 307244
Summary:
GlobalExtensions is dereferenced twice, once for iteration and then a check if it is empty.
As a ManagedStatic this dereference forces it's construction which is unnecessary.
Reviewers: efriedma, davide, mehdi_amini
Reviewed By: mehdi_amini
Subscribers: chapuni, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D33381
llvm-svn: 307229
LLVM's definition of dominance allows instructions that are cyclic
in unreachable blocks, e.g.:
%pat = select i1 %condition, @global, i16* %pat
because any instruction dominates an instruction in a block that's
not reachable from entry.
So, remove unreachable blocks from the function, because a) there's
no point in analyzing them and b) GlobalOpt should otherwise grow
some more complicated logic to break these cycles.
Differential Revision: https://reviews.llvm.org/D35028
llvm-svn: 307215
This adds exact flags to AShr/LShr flags where we can statically
prove it is valid using the range of induction variables. This
allows further optimisations to remove extra loads.
Differential Revision: https://reviews.llvm.org/D34207
llvm-svn: 307157
This patch seems to cause failures of test MathExtras.SaturatingMultiply on
multiple buildbots. Reverting until the reason of that is clarified.
Differential Revision: https://reviews.llvm.org/rL307126
llvm-svn: 307135
-If there is a IndVar which is known to be non-negative, and there is a value which is also non-negative,
then signed and unsigned comparisons between them produce the same result. Both of those can be
seen in the same loop. To allow other optimizations to simplify them, we turn all instructions like
%c = icmp slt i32 %iv, %b
to
%c = icmp ult i32 %iv, %b
if both %iv and %b are known to be non-negative.
Differential Revision: https://reviews.llvm.org/D34979
llvm-svn: 307126
Summary: This makes it easier to find out which limitation prevented this pass from doing its work.
Reviewers: karthikthecool, mzolotukhin, efriedma, mcrosier
Reviewed By: mcrosier
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D34940
llvm-svn: 307035
This reverts commit r306313. This breaks selfhost at -O3 and PR33652.
Let me know if you need additional information on reproducing the issue.
llvm-svn: 307021
We assumed the constant was a scalar when creating the replacement operand.
Also, improve tests for this fold and move the tests for this fold to their own file.
I'll move the related and missing tests to this file as a follow-up.
llvm-svn: 306985
I noticed this missed bswap optimization in the CGP memcmp() expansion,
and then I saw that we don't have the fold in InstCombine.
Differential Revision: https://reviews.llvm.org/D34763
llvm-svn: 306980
Summary:
I came across this while thinking about what would happen if one of the operands in this xor pattern was itself a inverted (A & ~B) ^ (~A & B)-> (A^B).
The patterns here assume that the (~a | ~b) will be demorganed to ~(a & b) first. Though I wonder if there's a multiple use case that would prevent the demorgan.
Reviewers: spatel
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34870
llvm-svn: 306967
This commit pretty much rolls back the logic added in r306495
as in the testcase provided we simplify an `icmp` looking through
a PHI that hasn't been mapped yet.
I think instsimplify shouldn't do threading over select/phis or
just looking through phis in general, but this is what we have
now. Also, add a test to prevent this from happening in case somebody
wants to modify this code again.
Briefly discussed with Kyle Butt (thanks Kyle!).
llvm-svn: 306938
With fix for use-after-free errors. We can't add the new branch and
remove the old one until we are done with the Builder constructed for
the block.
llvm-svn: 306937
Summary:
vectorizer-maximize-bandwidth is generally useful in terms of performance. I've tested the impact of changing this to default on speccpu benchmarks on sandybridge machines. The result shows non-negative impact:
spec/2006/fp/C++/444.namd 26.84 -0.31%
spec/2006/fp/C++/447.dealII 46.19 +0.89%
spec/2006/fp/C++/450.soplex 42.92 -0.44%
spec/2006/fp/C++/453.povray 38.57 -2.25%
spec/2006/fp/C/433.milc 24.54 -0.76%
spec/2006/fp/C/470.lbm 41.08 +0.26%
spec/2006/fp/C/482.sphinx3 47.58 -0.99%
spec/2006/int/C++/471.omnetpp 22.06 +1.87%
spec/2006/int/C++/473.astar 22.65 -0.12%
spec/2006/int/C++/483.xalancbmk 33.69 +4.97%
spec/2006/int/C/400.perlbench 33.43 +1.70%
spec/2006/int/C/401.bzip2 23.02 -0.19%
spec/2006/int/C/403.gcc 32.57 -0.43%
spec/2006/int/C/429.mcf 40.35 +0.27%
spec/2006/int/C/445.gobmk 26.96 +0.06%
spec/2006/int/C/456.hmmer 24.4 +0.19%
spec/2006/int/C/458.sjeng 27.91 -0.08%
spec/2006/int/C/462.libquantum 57.47 -0.20%
spec/2006/int/C/464.h264ref 46.52 +1.35%
geometric mean +0.29%
The regression on 453.povray seems real, but is due to secondary effects as all hot functions are bit-identical with and without the flag.
I started this patch to consult upstream opinions on this. It will be greatly appreciated if the community can help test the performance impact of this change on other architectures so that we can decided if this should be target-dependent.
Reviewers: hfinkel, mkuper, davidxl, chandlerc
Reviewed By: chandlerc
Subscribers: rengolin, sanjoy, javed.absar, bjope, dorit, magabari, RKSimon, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33341
llvm-svn: 306933
We aren't looking through any levels of IR here so I don't think we need the power of a matcher or the temporary variable it requires.
llvm-svn: 306885
Check if a single cast is preventing handling a first-order-recurrence Phi,
because the scheduling constraints it imposes on the first-order-recurrence
shuffle are infeasible; but they can be made feasible by moving the cast
downwards. Record such casts and move them when vectorizing the loop.
Differential Revision: https://reviews.llvm.org/D33058
llvm-svn: 306884
This patch appends the name of the function to the switch generated lookup
table. This will ease the visual debugging in identifying the function the table
is generated from.
Differential Revision: https://reviews.llvm.org/D34817
llvm-svn: 306867
Summary:
Runtime unrolling is done for loops with a single exit block and a
single exiting block (and this exiting block should be the latch block).
This patch adds logic to support unrolling in the presence of multiple exit
blocks (which also means multiple exiting blocks).
Currently this is under an off-by-default option and is supported when
epilog code is generated. Support in presence of prolog code will be in
a future patch (we just need to add more tests, and update comments).
This patch is essentially an implementation patch. I have not added any
heuristic (in terms of branches added or code size) to decide when
this should be enabled.
Reviewers: mkuper, sanjoy, reames, evstupac
Reviewed by: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33001
llvm-svn: 306846
It may be detrimental to vectorize loops with very small trip count, as various
costs of the vectorized loop body as well as enclosing overheads including
runtime tests and scalar iterations may outweigh the gains of vectorizing. The
current cost model measures the cost of the vectorized loop body only, expecting
it will amortize other costs, and loops with known or expected very small trip
counts are not vectorized at all. This patch allows loops with very small trip
counts to be vectorized, but under OptForSize constraints, which ensure the cost
of the loop body is dominant, having no runtime guards nor scalar iterations.
Patch inspired by D32451.
Differential Revision: https://reviews.llvm.org/D34373
llvm-svn: 306803
There are two conditions ORed here with similar checks and each contain two matches that must be true for the if to succeed. With the commutable match on the first half of the OR then both ifs basically have the same first part and only the second part distinguishs. With this change we move the commutable match to second half and make the first half unique.
This caused some tests to change because we now produce a commuted result, but this shouldn't matter in practice.
llvm-svn: 306800
It served us well, helped kick-start much of the vectorization efforts
in LLVM, etc. Its time has come and past. Back in 2014:
http://lists.llvm.org/pipermail/llvm-dev/2014-November/079091.html
Time to actually let go and move forward. =]
I've updated the release notes both about the removal and the
deprecation of the corresponding C API.
llvm-svn: 306797
In rL300494 there was an attempt to deal with excessive compile time on
invocations of getSign/ZeroExtExpr using local caching. This approach only
helps if we request the same SCEV multiple times throughout recursion. But
in the bug PR33431 we see a case where we request different values all the time,
so caching does not help and the size of the cache grows enormously.
In this patch we remove the local cache for this methods and add the recursion
depth limit instead, as we do for arithmetics. This gives us a guarantee that the
invocation sequence is limited and reasonably short.
Differential Revision: https://reviews.llvm.org/D34273
llvm-svn: 306785
The style guide states that the explicit `inline`
should not be used with inline methods. classof is
very common inline method with a fair amount on
inconsistency:
$ git grep classof ./include | grep inline | wc -l
230
$ git grep classof ./include | grep -v inline | wc -l
257
I chose to target this method rather the larger change
since this method is easily cargo-culted (I did it at
least once). I considered doing the larger change and
removing all occurrences but that would be a much larger
change.
Differential Revision: https://reviews.llvm.org/D33906
llvm-svn: 306731
Summary:
Indices for GEPs that index into a struct type should always be
constants. This added more checks in `collectConstantCandidates:` which make
sure constants for GEP pointer type are not hoisted.
This fixed Bug https://bugs.llvm.org/show_bug.cgi?id=33538
Reviewers: ributzka, rnk
Reviewed By: ributzka
Subscribers: efriedma, llvm-commits, srhines, javed.absar, pirama
Differential Revision: https://reviews.llvm.org/D34576
llvm-svn: 306704
Summary:
As discussed on the mailing list it is legal to propagate TBAA to loads/stores
from/to smaller regions of a larger load tagged with TBAA. Do so for
(load->extractvalue)=>(gep->load) and similar foldings.
Reviewed By: sanjoy
Differential Revision: https://reviews.llvm.org/D31954
llvm-svn: 306615
r306381 caused PR33613, by reversing the order in which insertelements were
generated per unroll part. This patch fixes PR33613 by retraining this order,
placing each set of insertelements per part immediately after the last scalar
being packed for this part. Includes a test case derived from PR33613.
Reference: https://bugs.llvm.org/show_bug.cgi?id=33613
Differential Revision: https://reviews.llvm.org/D34760
llvm-svn: 306575
Summary:
I was testing using this expansion logic in other cases besides
NVPTX, and found some runtime failures due to the lack of a check
for a zero length memcpy/memset before the loop. There is already
such a check in the memmove expansion code though.
Reviewers: hfinkel
Subscribers: jholewinski, wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D34707
llvm-svn: 306541
Summary:
This commit allows matchSelectPattern to recognize clamp of float
arguments in the presence of FMF the same way as already done for
integers.
This case is a little different though. With integers, given the
min/max pattern is recognized, DAGBuilder starts selecting MIN/MAX
"automatically". That is not the case for float, because for them only
full FMINNAN/FMINNUM/FMAXNAN/FMAXNUM ISD nodes exist and they do care
about NaNs. On the other hand, some backends (e.g. X86) have only
FMIN/FMAX nodes that do not care about NaNS and the former NAN/NUM
nodes are illegal thus selection is not happening. So I decided to do
such kind of transformation in IR (InstCombiner) instead of
complicating the logic in the backend.
Reviewers: spatel, jmolloy, majnemer, efriedma, craig.topper
Reviewed By: efriedma
Subscribers: hiraditya, javed.absar, n.bozhenov, llvm-commits
Patch by Andrei Elovikov <andrei.elovikov@intel.com>
Differential Revision: https://reviews.llvm.org/D33186
llvm-svn: 306525
A slightly more efficient way to get constant, we avoid resolving in getSCEV and excessive
invocations, and we don't create a ConstantInt if 'true' branch is taken.
Differential Revision: https://reviews.llvm.org/D34672
llvm-svn: 306503
When simplifying an instruction that has been re-mapped, it should never
simplify to an instruction in the original function. In the edge case
where we are inlining a function into itself, the existing code led to
incorrect behavior. Replace the incorrect code with an assert verifying
that we never expect simplification to produce an instruction in the old
function, unless the functions are the same.
Differential Revision: https://reviews.llvm.org/D33850
llvm-svn: 306495
The check to see if we can propagate the nsw flag used m_ConstantInt(uint64_t*&) which doesn't work with splat vectors and has a restriction that the bitwidth of the ConstantInt must be 64-bits are less.
This patch changes it to use m_APInt to remove both these issues
Differential Revision: https://reviews.llvm.org/D34699
llvm-svn: 306457
BlockAddress are only valid within their function context, which does not
interact well with CodeExtractor. Detect this case and prevent it.
Differential Revision: https://reviews.llvm.org/D33839
llvm-svn: 306448
SROA assumes alloca address space is 0, which causes assertion. This patch fixes that.
Differential Revision: https://reviews.llvm.org/D34104
llvm-svn: 306440
This canonicalization was suggested in D33172 as a way to make InstCombine behavior more uniform.
We have this transform for icmp+br, so unless there's some reason that icmp+select should be
treated differently, we should do the same thing here.
The benefit comes from increasing the chances of creating identical instructions. This is shown in
the tests in logical-select.ll (PR32791). InstCombine doesn't fold those directly, but EarlyCSE
can simplify the identical cmps, and then InstCombine can fold the selects together.
The possible regression for the tests in select.ll raises questions about poison/undef:
http://lists.llvm.org/pipermail/llvm-dev/2017-May/113261.html
...but that transform is just as likely to be triggered by this canonicalization as it is to be
missed, so we're just pointing out a commutation deficiency in the pattern matching:
https://reviews.llvm.org/rL228409
Differential Revision: https://reviews.llvm.org/D34242
llvm-svn: 306435
Instead of getBackEdgeTakenCount, use getExitCount on the latch exiting block
(which is proven to be the only exiting block in the loop to be unrolled).
llvm-svn: 306410
Undoing revert 306338 after fixed bug: add metadata to the load instead of the
reverse shuffle added to it, retaining the original ValueMap implementation.
llvm-svn: 306381
This is based heavily on the work done ni D34285. I mostly wanted to do
test cleanup for the author to save them some time, but I had a really
hard time understanding why it was so hard to write better test cases
for these issues.
The problem is that because SROA does a second rewrite of the loads and
because we *don't* propagate !nonnull for non-pointer loads, we first
introduced invalid !nonnull metadata and then stripped it back off just
in time to avoid most ways of this PR manifesting. Moving to the more
careful utility only fixes this by changing the predicate to look at the
new load's type rather than the target type. However, that *does* fix
the bug, and the utility is much nicer including adding range metadata
to model the nonnull property after a conversion to an integer.
However, we have bigger problems because we don't actually propagate
*range* metadata, and the utility to do this extracted from instcombine
isn't really in good shape to do this currently. It *only* handles the
case of copying range metadata from an integer load to a pointer load.
It doesn't even handle the trivial cases of propagating from one integer
load to another when they are the same width! This utility will need to
be beefed up prior to using in this location to get the metadata to
fully survive.
And even then, we need to go and teach things to turn the range metadata
into an assume the way we do with nonnull so that when we *promote* an
integer we don't lose the information.
All of this will require a new test case that looks kind-of like
`preserve-nonnull.ll` does here but focuses on range metadata. It will
also likely require more testing because it needs to correctly handle
changes to the integer width, especially as SROA actively tries to
change the integer width!
Last but not least, I'm a little worried about hooking the range
metadata up here because the instcombine logic for converting from
a range metadata *to* a nonnull metadata node seems broken in the face
of non-zero address spaces where null is not mapped to the integer `0`.
So that probably needs to get fixed with test cases both in SROA and in
instcombine to cover it.
But this *does* extract the core PR fix from D34285 of preventing the
!nonnull metadata from being propagated in a broken state just long
enough to feed into promotion and crash value tracking.
On D34285 there is some discussion of zero-extend handling because it
isn't necessary. First, the new load size covers all of the non-undef
(ie, possibly initialized) bits. This may even extend past the original
alloca if loading those bits could produce valid data. The only way its
valid for us to zero-extend an integer load in SROA is if the original
code had a zero extend or those bits were undef. And we get to assume
things like undef *never* satifies nonnull, so non undef bits can
participate here. No need to special case the zero-extend handling, it
just falls out correctly.
The original credit goes to Ariel Ben-Yehuda! I'm mostly landing this to
save a few rounds of trivial edits fixing style issues and test case
formulation.
Differental Revision: D34285
llvm-svn: 306379
Summary:
EraseInst didn't report that it made IR changes through MadeChange.
It is essential that changes to the IR are reported correctly,
since for example ReassociatePass::run() will indicate that all
analyses are preserved otherwise.
And the CGPassManager determines if the CallGraph is up-to-date
based on status from InstructionCombiningPass::runOnFunction().
Reviewers: craig.topper, rnk, davide
Reviewed By: rnk, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34616
llvm-svn: 306368
Summary:
vectorizer-maximize-bandwidth is generally useful in terms of performance. I've tested the impact of changing this to default on speccpu benchmarks on sandybridge machines. The result shows non-negative impact:
spec/2006/fp/C++/444.namd 26.84 -0.31%
spec/2006/fp/C++/447.dealII 46.19 +0.89%
spec/2006/fp/C++/450.soplex 42.92 -0.44%
spec/2006/fp/C++/453.povray 38.57 -2.25%
spec/2006/fp/C/433.milc 24.54 -0.76%
spec/2006/fp/C/470.lbm 41.08 +0.26%
spec/2006/fp/C/482.sphinx3 47.58 -0.99%
spec/2006/int/C++/471.omnetpp 22.06 +1.87%
spec/2006/int/C++/473.astar 22.65 -0.12%
spec/2006/int/C++/483.xalancbmk 33.69 +4.97%
spec/2006/int/C/400.perlbench 33.43 +1.70%
spec/2006/int/C/401.bzip2 23.02 -0.19%
spec/2006/int/C/403.gcc 32.57 -0.43%
spec/2006/int/C/429.mcf 40.35 +0.27%
spec/2006/int/C/445.gobmk 26.96 +0.06%
spec/2006/int/C/456.hmmer 24.4 +0.19%
spec/2006/int/C/458.sjeng 27.91 -0.08%
spec/2006/int/C/462.libquantum 57.47 -0.20%
spec/2006/int/C/464.h264ref 46.52 +1.35%
geometric mean +0.29%
The regression on 453.povray seems real, but is due to secondary effects as all hot functions are bit-identical with and without the flag.
I started this patch to consult upstream opinions on this. It will be greatly appreciated if the community can help test the performance impact of this change on other architectures so that we can decided if this should be target-dependent.
Reviewers: hfinkel, mkuper, davidxl, chandlerc
Reviewed By: chandlerc
Subscribers: rengolin, sanjoy, javed.absar, bjope, dorit, magabari, RKSimon, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33341
llvm-svn: 306336
Instead of providing access to the internal MapStorage holding all Values
associated with a given Key, used for setting or resetting them all together,
ValueMap keeps its MapStorage internal; its new interface allows getting,
setting or resetting a single Value, per part or per part-and-lane.
Follows the discussion in https://reviews.llvm.org/D32871.
Differential Revision: https://reviews.llvm.org/D34473
llvm-svn: 306331
The recommit fixes three bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available. The third one is an out-of-bound
array access in a flipped if guard.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
llvm-svn: 306313
metadata out of InstCombine and into helpers.
NFC, this just exposes the logic used by InstCombine when propagating
metadata from one load instruction to another. The plan is to use this
in SROA to address PR32902.
If anyone has better ideas about how to factor this or name variables,
I'm all ears, but this seemed like a pretty good start and lets us make
progress on the PR.
This is based on a patch by Ariel Ben-Yehuda (D34285).
llvm-svn: 306267
This was reverted in r306252, but I already had the bug fixed and was
just trying to form a test case.
The original commit factored the logic for forming dedicated exits
inside of LoopSimplify into a helper that could be used elsewhere and
with an approach that required fewer intermediate data structures. See
that commit for full details including the change to the statistic, etc.
The code looked fine to me and my reviewers, but in fact didn't handle
indirectbr correctly -- it left the 'InLoopPredecessors' vector dirty.
If you have code that looks *just* right, you can end up leaking these
predecessors into a subsequent rewrite, and crash deep down when trying
to update PHI nodes for predecessors that don't exist.
I've added an assert that makes the bug much more obvious, and then
changed the code to reliably clear the vector so we don't get this bug
again in some other form as the code changes.
I've also added a test case that *does* manage to catch this while also
giving some nice positive coverage in the face of indirectbr.
The real code that found this came out of what I think is CPython's
interpreter loop, but any code with really "creative" interpreter loops
mixing indirectbr and other exit paths could manage to tickle the bug.
I was hard to reduce the original test case because in addition to
having a particular pattern of IR, the whole thing depends on the order
of the predecessors which is in turn depends on use list order. The test
case added here was designed so that in multiple different predecessor
orderings it should always end up going down the same path and tripping
the same bug. I hope. At least, it tripped it for me without
manipulating the use list order which is better than anything bugpoint
could do...
llvm-svn: 306257
Recommit NFC patch (rL306157) where I missed incrementing the basic block iterator,
which caused loop deletion tests to hang due to infinite loop.
Had reverted it in rL306162.
rL306157 commit message:
Currently, the implementation of delete dead loops has a special case
when the loop being deleted is never executed. This special case
(updating of exit block's incoming values for phis) can be
run as a prepass for non-executable loops before performing
the actual deletion.
llvm-svn: 306254
http://rise4fun.com/Alive/i8Q
A narrow bitwise logic op is obviously better than math for value tracking,
and zext is better than sext. Typically, the 'not' will be folded into an
icmp predicate.
The IR difference would even survive through codegen for x86, so we would see
worse code:
https://godbolt.org/g/C14HMF
one_or_zero(int, int): # @one_or_zero(int, int)
xorl %eax, %eax
cmpl %esi, %edi
setle %al
retq
one_or_zero_alt(int, int): # @one_or_zero_alt(int, int)
xorl %ecx, %ecx
cmpl %esi, %edi
setg %cl
movl $1, %eax
subl %ecx, %eax
retq
llvm-svn: 306243
Summary:
InstCombine replaces large allocas with small globals consts causing buffer overflows
on valid code, see PR33372.
This fix permits this optimization only if the global is dereference for alloca size.
Fixes PR33372
Reviewers: eugenis, majnemer, chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34311
llvm-svn: 306194
This reverts commit r306157.
It caused some timeouts in clang tests. Perhaps unreachable loops have
far too many phi nodes.
Reverting and investigating.
llvm-svn: 306162
Currently, the implementation of delete dead loops has a special case
when the loop being deleted is never executed. This special case
(updating of exit block's incoming values for phis) can be
run as a prepass for non-executable loops before performing
the actual deletion.
llvm-svn: 306157
Summary:
Many languages have a three way comparison idiom where comparing two values
produces not a boolean, but a tri-state value. Typical values (e.g. as used in
the lcmp/fcmp bytecodes from Java) are -1 for less than, 0 for equality, and +1
for greater than.
We actually do a great job already of converting three way comparisons into
binary comparisons when the result produced has one a single use. Unfortunately,
such values can have more than one use, and in that case, our existing
optimizations break down.
The patch adds a peephole which converts a three-way compare + test idiom into a
binary comparison on the original inputs. It focused on replacing the test on
the result of the three way compare and does nothing about removing the three
way compare itself. That's left to other optimizations (which do actually kick
in commonly.)
We currently recognize one idiom on signed integer compare. In the future, we
plan to recognize and simplify other comparison idioms on
other signed/unsigned datatypes such as floats, vectors etc.
This is a resurrection of Philip Reames' original patch:
https://reviews.llvm.org/D19452
Reviewers: majnemer, apilipenko, reames, sanjoy, mkazantsev
Reviewed by: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34278
llvm-svn: 306100
Currently JumpThreading can use LazyValueInfo to analyze an 'and' or 'or' of compare if the compare is fed by a livein of a basic block. This can be used to to prove the condition can't be met for some predecessor and the jump from that predecessor can be moved to the false path of the condition.
But if the compare is something that InstCombine turns into an add and a single compare, it can't be analyzed because the livein is now an input to the add and not the compare.
This patch adds a new method to LVI to get a ConstantRange on an edge. Then we teach jump threading to detect the add livein feeding a compare and to get the ConstantRange and propagate it.
Differential Revision: https://reviews.llvm.org/D33262
llvm-svn: 306085
I want to use the same logic as LoopSimplify to form dedicated exits in
another pass (SimpleLoopUnswitch) so I wanted to factor it out here.
I also noticed that there is a pretty significantly more efficient way
to implement this than the way the code in LoopSimplify worked. We don't
need to actually retain the set of unique exit blocks, we can just
rewrite them as we find them and use only a set to deduplicate.
This did require changing one part of LoopSimplify to not re-use the
unique set of exits, but it only used it to check that there was
a single unique exit. That part of the code is about to walk the exiting
blocks anyways, so it seemed better to rewrite it to use those exiting
blocks to compute this property on-demand.
I also had to ditch a statistic, but it doesn't seem terribly valuable.
Differential Revision: https://reviews.llvm.org/D34049
llvm-svn: 306081
Summary:
Currently, we incorrectly update exit blocks of loops when there are multiple
edges from a single exiting block to the exit block. This can happen when we
have switches as the terminator of the exiting blocks.
The fix here is to correctly update the phi nodes in the exit block, and remove
all incoming values *except* for one which is from the preheader.
Note: Currently, this error can manifest only while deleting non-executed loops. However, it
is possible to trigger this error in invariant loops, once we enhance the logic
around the exit conditions for the loop check.
Reviewers: chandlerc, dberlin, sanjoy, efriedma
Reviewed by: efriedma
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D34516
llvm-svn: 306048
Summary:
InstCombine likes to turn (icmp eq (and X, C1), 0) into (icmp slt (trunc (X)), 0) sometimes. This breaks foldSelectICmpAndOr's ability to recognize (select (icmp eq (and X, C1), 0), Y, (or Y, C2))->(or (shl (and X, C1), C3), y).
This patch tries to recover this. I had to flip around some of the early out checks so that I could create a new And instruction during the compare processing without it possibly never getting used.
Reviewers: spatel, majnemer, davide
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34184
llvm-svn: 306029
If the components of the and/or had multiple uses, this transform created an additional instruction.
This patch makes sure we remove one of the components.
Differential Revision: https://reviews.llvm.org/D34498
llvm-svn: 306027
There are 2 parts to this patch made simultaneously to avoid a regression.
We're reversing the canonicalization that moves bitwise vector ops before bitcasts.
We're moving bitwise vector ops *after* bitcasts instead. That's the 1st and 3rd hunks
of the patch. The motivation is that there's only one fold that currently depends on
the existing canonicalization (see next), but there are many folds that would
automatically benefit from the new canonicalization.
PR33138 ( https://bugs.llvm.org/show_bug.cgi?id=33138 ) shows why/how we have these
patterns in IR.
There's an or(and,andn) pattern that requires an adjustment in order to continue matching
to 'select' because the bitcast changes position. This match is unfortunately complicated
because it requires 4 logic ops with optional bitcast and sext ops.
Test diffs:
1. The bitcast.ll and bitcast-bigendian.ll changes show the most basic difference -
bitcast comes before logic.
2. There are also tests with no diffs in bitcast.ll that verify that we're still doing
folds that were enabled by the previous canonicalization.
3. icmp-xor-signbit.ll shows the payoff. We don't need to adjust existing icmp patterns
to look through bitcasts.
4. logical-select.ll contains several tests for the or(and,andn) --> select fold to
verify that we are still handling those cases. The lone diff shows the movement of
the bitcast from the new canonicalization rule.
Differential Revision: https://reviews.llvm.org/D33517
llvm-svn: 306011
Summary:
vectorizer-maximize-bandwidth is generally useful in terms of performance. I've tested the impact of changing this to default on speccpu benchmarks on sandybridge machines. The result shows non-negative impact:
spec/2006/fp/C++/444.namd 26.84 -0.31%
spec/2006/fp/C++/447.dealII 46.19 +0.89%
spec/2006/fp/C++/450.soplex 42.92 -0.44%
spec/2006/fp/C++/453.povray 38.57 -2.25%
spec/2006/fp/C/433.milc 24.54 -0.76%
spec/2006/fp/C/470.lbm 41.08 +0.26%
spec/2006/fp/C/482.sphinx3 47.58 -0.99%
spec/2006/int/C++/471.omnetpp 22.06 +1.87%
spec/2006/int/C++/473.astar 22.65 -0.12%
spec/2006/int/C++/483.xalancbmk 33.69 +4.97%
spec/2006/int/C/400.perlbench 33.43 +1.70%
spec/2006/int/C/401.bzip2 23.02 -0.19%
spec/2006/int/C/403.gcc 32.57 -0.43%
spec/2006/int/C/429.mcf 40.35 +0.27%
spec/2006/int/C/445.gobmk 26.96 +0.06%
spec/2006/int/C/456.hmmer 24.4 +0.19%
spec/2006/int/C/458.sjeng 27.91 -0.08%
spec/2006/int/C/462.libquantum 57.47 -0.20%
spec/2006/int/C/464.h264ref 46.52 +1.35%
geometric mean +0.29%
The regression on 453.povray seems real, but is due to secondary effects as all hot functions are bit-identical with and without the flag.
I started this patch to consult upstream opinions on this. It will be greatly appreciated if the community can help test the performance impact of this change on other architectures so that we can decided if this should be target-dependent.
Reviewers: hfinkel, mkuper, davidxl, chandlerc
Reviewed By: chandlerc
Subscribers: rengolin, sanjoy, javed.absar, bjope, dorit, magabari, RKSimon, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33341
llvm-svn: 305960
Summary: r305009 disables recursive inlining for indirect calls in sample loader pass. The same logic applies to direct recursive calls.
Reviewers: iteratee, davidxl
Reviewed By: iteratee
Subscribers: sanjoy, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D34456
llvm-svn: 305934
Summary:
I noticed that passing known bits across these intrinsics isn't great at capturing the information we really know. Turning known bits of the input into known bits of a count output isn't able to convey a lot of what we really know.
This patch adds range metadata to these intrinsics based on the known bits.
Currently the patch punts if we already have range metadata present.
Reviewers: spatel, RKSimon, davide, majnemer
Reviewed By: RKSimon
Subscribers: sanjoy, hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D32582
llvm-svn: 305927
Summary:
Previously this folding had no checks to see if it was going to result in less instructions. This was pointed out during the review of D34184
This patch adds code to count how many instructions its going to create vs how many its going to remove so we can make a proper decision.
Reviewers: spatel, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34437
llvm-svn: 305926
We weren't actually checking for duplicated stores, as the condition
was always actually false. This was found by Coverity, and I have
no clue how to trigger this in real-world code (although I
tried for a bit).
llvm-svn: 305867
We have a large portfolio of folds for and-of-icmps and or-of-icmps in InstSimplify and InstCombine,
but hardly anything for xor-of-icmps. Rather than trying to rethink and translate all of those folds,
we can use the truth table definition of xor:
X ^ Y --> (X | Y) & !(X & Y)
...to see if we can convert the xor to and/or and then use the existing folds.
http://rise4fun.com/Alive/J9v
Differential Revision: https://reviews.llvm.org/D33342
llvm-svn: 305792
With PR33517, it became apparent that symbol table creation can fail
when presented with malformed inputs. This patch makes that sort of
error detectable, so llvm-cov etc. can fail more gracefully.
Specifically, we now check that function names within the symbol table
aren't empty.
Testing: check-{llvm,clang,profile}, some unit test updates.
llvm-svn: 305765
Summary:
Existing heuristic uses the ratio between the function entry
frequency and the loop invocation frequency to find cold loops. However,
even if the loop executes frequently, if it has a small trip count per
each invocation, vectorization is not beneficial. On the other hand,
even if the loop invocation frequency is much smaller than the function
invocation frequency, if the trip count is high it is still beneficial
to vectorize the loop.
This patch uses estimated trip count computed from the profile metadata
as a primary metric to determine coldness of the loop. If the estimated
trip count cannot be computed, it falls back to the original heuristics.
Reviewers: Ayal, mssimpso, mkuper, danielcdh, wmi, tejohnson
Reviewed By: tejohnson
Subscribers: tejohnson, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D32451
llvm-svn: 305729
Summary:
Some optimizations in AddReachableCodeToWorklist did not update
the MadeIRChange state. This could happen both when removing
trivially dead instructions (DCE) and at constant folds.
It is essential that changes to the IR is reported correctly,
since for example InstCombinePass::run() will indicate that all
analyses are preserved otherwise.
And the CGPassManager determines if the CallGraph is up-to-date
based on status from InstructionCombiningPass::runOnFunction().
The new test case early_dce_clobbers_callgraph.ll is a reproducer
for some asserts that started to trigger after changes in the
inliner in r305245. With this patch the test case passes again.
Reviewers: sanjoy, craig.topper, dblaikie
Reviewed By: craig.topper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34346
llvm-svn: 305725
This seems to be interacting badly with ASan somehow, causing false reports of
heap-buffer overflows: PR33514.
> Summary:
> The patch makes instruction count the highest priority for
> LSR solution for X86 (previously registers had highest priority).
>
> Reviewers: qcolombet
>
> Differential Revision: http://reviews.llvm.org/D30562
>
> From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 305720
Summary:
These 4 patterns have the same one use check repeated twice for each. Once without a cast and one with. But the cast has no effect on what method is called.
For the OR case I believe it is always profitable regardless of the number of uses since we'll never increase the instruction count.
For the AND case I believe it is profitable if the pair of xors has one use such that we'll get rid of it completely. Or if the C value is something freely invertible, in which case the not doesn't cost anything.
Reviewers: spatel, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34308
llvm-svn: 305705
Summary:
Currently we don't try to do anything with vector xors.
This patch adds support for removing duplicate pairs from a chain of vector xors as its pretty easy to support. We still dont' try to combine the xors with and/ors, but I might try that in a future patch.
Reviewers: mcrosier, davide, resistor
Reviewed By: mcrosier
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34338
llvm-svn: 305704
Summary:
After a single predecessor is merged into a basic block, we need to invalidate
the LVI information for the new merged block, when LVI is not provably true for
all of instructions in the new block.
The test cases added show the correct LVI information using the LVI printer
pass.
Reviewers: reames, dberlin, davide, sanjoy
Reviewed by: dberlin, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34108
llvm-svn: 305699
Summary: use AA to tell whether a load can be moved before a call that writes to memory.
Reviewers: dberlin, davide, sanjoy, hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D34115
llvm-svn: 305698
Summary:
This allows strlen to be moved out of the loop in case its argument is
not modified in the loop in LICM.
Reviewers: hfinkel, davide, sanjoy, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34323
llvm-svn: 305641
Summary:
When we fold vector constants that are operands of phi's that feed into select,
we need to set the correct insertion point for the *new* selects that get generated.
The correct insertion point is the incoming block for the phi.
Such cases can occur with patch r298845, which fixed folding of
vector constants, but the new selects could be inserted incorrectly (as the added
test case shows).
Reviewers: majnemer, spatel, sanjoy
Reviewed by: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34162
llvm-svn: 305591
The recommit fixes two bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
llvm-svn: 305578
Summary:
Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html
This change is to alter the prototype for the atomic memcpy intrinsic. The prototype itself is being changed to more closely resemble the semantics and parameters of the llvm.memcpy intrinsic -- to ease later combination of the llvm.memcpy and atomic memcpy intrinsics. Furthermore, the name of the atomic memcpy intrinsic is being changed to make it clear that it is not a generic atomic memcpy, but specifically a memcpy is unordered atomic.
Reviewers: reames, sanjoy, efriedma
Reviewed By: reames
Subscribers: mzolotukhin, anna, llvm-commits, skatkov
Differential Revision: https://reviews.llvm.org/D33240
llvm-svn: 305558
Summary: This is the demorganed version of the case we already handle for the OR of iszero.
Reviewers: spatel
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34244
llvm-svn: 305548
Summary:
Split the PGOMemOPSizeOpt pass out from IndirectCallPromotion.cpp into
its own file.
Reviewers: davidxl
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D34248
llvm-svn: 305501
Currently we expect A to be on the same side in both Ands but nothing guarantees that.
While there also switch to using matchers for some of the code.
Differential Revision: https://reviews.llvm.org/D34230
llvm-svn: 305487
This is a fix for PR33292 that shows a case of extremely long compilation
of a single .c file with clang, with most time spent within SCEV.
We have a mechanism of limiting recursion depth for getAddExpr to avoid
long analysis in SCEV. However, there are calls from getAddExpr to getMulExpr
and back that do not propagate the info about depth. As result of this, a chain
getAddExpr -> ... .> getAddExpr -> getMulExpr -> getAddExpr -> ... -> getAddExpr
can be extremely long, with every segment of getAddExpr's being up to max depth long.
This leads either to long compilation or crash by stack overflow. We face this situation while
analyzing big SCEVs in the test of PR33292.
This patch applies the same limit on max expression depth for getAddExpr and getMulExpr.
Differential Revision: https://reviews.llvm.org/D33984
llvm-svn: 305463
This way we end up not looking at PHI args already removed.
MemSSA now goes through the updater so we can prune
it to avoid having redundant MemoryPHI arguments, but that
doesn't quite work for the general case.
Discussed with Daniel Berlin, fixes PR33406.
llvm-svn: 305409
Doing so breaks compilation of the following C program
(under -fprofile-instr-generate):
__attribute__((always_inline)) inline int foo() { return 0; }
int main() { return foo(); }
At link time, we fail because taking the address of an
available_externally function creates an undefined external reference,
which the TU cannot provide.
Emitting the function definition into the object file at all appears to
be a violation of the langref: "Globals with 'available_externally'
linkage are never emitted into the object file corresponding to the LLVM
module."
Differential Revision: https://reviews.llvm.org/D34134
llvm-svn: 305327
Summary:
Leave an updated VP metadata on the fallback memcpy intrinsic after
specialization. This can be used for later possible expansion based on
the average of the remaining values.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34164
llvm-svn: 305321
Summary: Fixes an issue using RegisterStandardPasses from a statically linked object before PassManagerBuilder::addGlobalExtension is called from a dynamic library.
Reviewers: efriedma, theraven
Reviewed By: efriedma
Subscribers: mehdi_amini, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33515
llvm-svn: 305303
This restores the order of evaluation (& conditionalized evaluation) of
isTriviallyDeadInstruction, InlineHistoryIncludes, and shouldInline
(with the addition of a shouldInline call after
isTriviallyDeadInstruction) from before r305245.
llvm-svn: 305267
Summary:
After RS4GC, we should drop metadata that is no longer valid. These metadata
is used by optimizations scheduled after RS4GC, and can cause a miscompile.
One such metadata is invariant.load which is used by LICM sinking transform.
After rewriting statepoints, the address of a load maybe relocated. With
invariant.load metadata on a load instruction, LICM sinking assumes the
loaded value (from a dererenceable address) to be invariant, and
rematerializes the load operand and the load at the exit block.
This transforms the IR to have an unrelocated use of the
address after a statepoint, which is incorrect.
Other metadata we conservatively remove are related to
dereferenceability and noalias metadata.
This patch drops such metadata on store and load instructions after
rewriting statepoints.
Reviewers: reames, sanjoy, apilipenko
Reviewed by: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33756
llvm-svn: 305234
Summary:
Use MemorySSA for memory dependency checking in the EarlyCSE pass at the
start of the function simplification portion of the pipeline. We rely
on the fact that GVNHoist runs just after this pass of EarlyCSE to
amortize the MemorySSA construction cost since GVNHoist uses MemorySSA
and EarlyCSE preserves it.
This is turned off by default. A follow-up change will turn it on to
allow for easier reversion in case it breaks something.
llvm-svn: 305146
Currently there is a bug in SROA::presplitLoadsAndStores which causes assertion in
GEPOperator::accumulateConstantOffset.
Basically it does not consider the situation that the pointer operand of load or store
may be in a non-zero address space and its size may be different from the size of
a pointer in address space 0.
This patch fixes assertion when compiling Blender Cycles kernels for amdgpu backend.
Diffferential Revision: https://reviews.llvm.org/D33298
llvm-svn: 305107
Summary:
isSafeToSpeculativelyExecute is the wrong predicate to use here.
All that checks for is whether it is safe to hoist a value due to
unaligned/un-dereferencable accesses. However, not only are we doing
sinking rather than hoisting, our concern is that the location
we're loading from may have been modified. Instead forbid sinking
any load across a critical edge.
Reviewers: majnemer
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D33179
llvm-svn: 305102
This change adds an option disable-lftr to be able to disable Linear Function Test Replace optimization.
By default option is off so current behavior is not changed.
Reviewers: reames, sanjoy, wmi, andreadb, apilipenko
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33979
llvm-svn: 305055
If we're shrinking a binary operation, it may be the case that the new
operations wraps where the old didn't. If this happens, the behavior
should be well-defined. So, we can't always carry wrapping flags with us
when we shrink operations.
If we do, we get incorrect optimizations in cases like:
void foo(const unsigned char *from, unsigned char *to, int n) {
for (int i = 0; i < n; i++)
to[i] = from[i] - 128;
}
which gets optimized to:
void foo(const unsigned char *from, unsigned char *to, int n) {
for (int i = 0; i < n; i++)
to[i] = from[i] | 128;
}
Because:
- InstCombine turned `sub i32 %from.i, 128` into
`add nuw nsw i32 %from.i, 128`.
- LoopVectorize vectorized the add to be `add nuw nsw <16 x i8>` with a
vector full of `i8 128`s
- InstCombine took advantage of the fact that the newly-shrunken add
"couldn't wrap", and changed the `add` to an `or`.
InstCombine seems happy to figure out whether we can add nuw/nsw on its
own, so I just decided to drop the flags. There are already a number of
places in LoopVectorize where we rely on InstCombine to clean up.
llvm-svn: 305053
Other comments/implications are that this isn't intended behavior (nor
perserved/reimplemented in the new inliner) & complicates fixing the
'inlining' of trivially dead calls without consulting the cost function
first.
llvm-svn: 305052
Summary: This matches the behavior we already had for compares and makes us consistent everywhere.
Reviewers: dberlin, hfinkel, spatel
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33604
llvm-svn: 305049
Since D17854 LinkerSubsectionsViaSymbols is unnecessary.
It is interfering with ThinLTO implementation of CFI-ICall, where
the aliases used on the !LinkerSubsectionsViaSymbols branch are
needed to export jump tables to ThinLTO backends.
This is the second attempt to land this change after fixing PR33316.
llvm-svn: 305031
This is to prepare to allow for dead stripping of globals in the
merged modules.
Differential Revision: https://reviews.llvm.org/D33921
llvm-svn: 305027
Summary: Early-inlining of recursive call makes the code size bloat exponentially. We should not disable it.
Reviewers: davidxl, dnovillo, iteratee
Reviewed By: iteratee
Subscribers: iteratee, llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D34017
llvm-svn: 305009
The zero heuristic assumes that integers are more likely positive than negative,
but this also has the effect of assuming that strcmp return values are more
likely positive than negative. Given that for nonzero strcmp return values it's
the ordering of arguments that determines the sign of the result there's no
reason to assume that's true.
Fix this by inspecting the LHS of the compare and using TargetLibraryInfo to
decide if it's strcmp-like, and if so only assume that nonzero is more likely
than zero i.e. strings are more often different than the same. This causes a
slight code generation change in the spec2006 benchmark 403.gcc, but with no
noticeable performance impact. The intent of this patch is to allow better
optimisation of dhrystone on Cortex-M cpus, but currently it won't as there are
also some changes that need to be made to if-conversion.
Differential Revision: https://reviews.llvm.org/D33934
llvm-svn: 304970
This was discussed in D33338. We have larger pattern-matching ending in a truncate that
we can reduce or remove by handling these smaller patterns first. Further motivation is
that narrower shift ops are easier for value tracking and zext is better than sext.
http://rise4fun.com/Alive/rhh
Name: boolshift
%sext = sext i1 %x to i8
%r = lshr i8 %sext, 7
=>
%r = zext i1 %x to i8
Name: noboolshift
%sext = sext i3 %x to i8
%r = lshr i8 %sext, 7
=>
%sh = lshr i3 %x, 2
%r = zext i3 %sh to i8
Differential Revision: https://reviews.llvm.org/D33879
llvm-svn: 304939
This makes it so that the code quality for CFI checks when compiling
with -O2 and linking with --lto-O0 is similar to that of the rest of
the code.
Reduces the size of a chrome binary built with -O2/--lto-O0 by
about 750KB.
Differential Revision: https://reviews.llvm.org/D33925
llvm-svn: 304921
I believe this code used to use APInt references which would have worked. But then they were changed to pointers to allow m_APInt to be used.
llvm-svn: 304875
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
Summary:
The patch makes instruction count the highest priority for
LSR solution for X86 (previously registers had highest priority).
Reviewers: qcolombet
Differential Revision: http://reviews.llvm.org/D30562
From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 304824
1. When there is no perfect iteration order, we can't let phi nodes
put themselves in terms of things that come later in the iteration
order, or we will endlessly cycle (the normal RPO algorithm clears the
hashtable to avoid this issue).
2. We are sometimes erasing the wrong expression (causing pessimism)
because our equality says loads and stores are the same.
We introduce an exact equality function and use it when erasing to
make sure we erase only identical expressions, not equivalent ones.
llvm-svn: 304807
Summary:
Expanding the loop idiom test for memcpy to also recognize
unordered atomic memcpy. The only difference for recognizing
an unordered atomic memcpy and instead of a normal memcpy is
that the loads and/or stores involved are unordered atomic operations.
Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html
Patch by Daniel Neilson!
Reviewers: reames, anna, skatkov
Reviewed By: reames, anna
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33243
llvm-svn: 304806
Summary:
We were canonizalizing the pre loop (into loop-simplify form) before
the post loop blocks were added into parent loop. This is incorrect when IRCE is
done on a subloop. The post-loop blocks are created, but not yet added to the
parent loop. So, loop-simplification on the pre-loop incorrectly updates
LoopInfo.
This patch corrects the ordering so that pre and post loop blocks are added to
parent loop (if any), and then the loops are canonicalized to LCSSA and
LoopSimplifyForm.
Reviewers: reames, sanjoy, apilipenko
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33846
llvm-svn: 304800
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
Summary:
This problem stems from the fact that instructions are allocated using new
in LLVM, i.e. there is no relationship that can be derived by just looking
at the pointer value.
This interface dispatches to appropriate dominance check given 2 instructions,
i.e. in case the instructions are in the same basic block, ordered basicblock
(with instruction numbering and caching) are used. Otherwise, dominator tree
is used.
This is a preparation patch for https://reviews.llvm.org/D32720
Reviewers: dberlin, hfinkel, davide
Subscribers: davide, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33380
llvm-svn: 304764
Summary:
The patch guard all instruction cost calculations with InsnCosts (-lsr-insns-cost) option.
Currently even if the option set to false we calculate and print (in debug mode) instruction costs.
Reviewers: qcolombet
Differential Revision: http://reviews.llvm.org/D33914
From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 304746
This fixes a bug that can cause extractelements with operands that
haven't been defined yet to be inserted at a wrong point when
optimising insertelements.
Patch by Karl Hylen.
Differential Revision: https://reviews.llvm.org/D33449
llvm-svn: 304701
Following the request made in https://reviews.llvm.org/D32871,
scalarizeInstruction() which is no longer overridden by InnerLoopUnroller is
hereby made non-virtual in InnerLoopVectorizer.
Should have been part of r297580 originally.
llvm-svn: 304685
Fixed some comments, added an additional description of the algorithms,
improved readability of the code.
Differential revision: https://reviews.llvm.org/D33320
llvm-svn: 304616
We'd called this "vm state" in the early days, but have long since standardized on calling it "deopt" in line with the operand bundle tag. Fix a few cases we'd missed.
llvm-svn: 304607
Minor optimization but mostly simplifies my debugging so I'm not dealing
with empty SCCNodeSets while investigating issues in this optimization.
llvm-svn: 304597
Summary:
Fixed some comments, added an additional description of the algorithms,
improved readability of the code.
Reviewers: anemet
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33320
llvm-svn: 304593
Summary:
As shown in the test case, SROA was crashing when trying to split
stores (to the alloca) of loads (from anywhere), because it assumed
the pointer operand to the loads and stores had to have the same
address space. This isn't the case. Make sure to use the correct
pointer type for both the load and the store.
Reviewed By: yaxunl
Differential Revision: https://reviews.llvm.org/D32593
llvm-svn: 304585
Since D17854 LinkerSubsectionsViaSymbols is unnecessary.
It is interfering with ThinLTO implementation of CFI-ICall, where
the aliases used on the !LinkerSubsectionsViaSymbols branch are
needed to export jump tables to ThinLTO backends.
llvm-svn: 304582
Summary:
Optimization passes may remove llvm.coro.suspend intrinsic while leaving matching llvm.coro.save intrinsic orphaned.
Make sure we clean up orphaned coro.saves. The bug manifested with a crash similar to this:
```
llvm_unreachable("Unknown type!");
llvm::MVT::getVT (Ty=0x489518, HandleUnknown=false)
llvm::EVT::getEVT
llvm::TargetLoweringBase::getValueType
llvm::ComputeValueVTs
llvm::SelectionDAGBuilder::visitTargetIntrinsic
```
Reviewers: GorNishanov
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D33817
llvm-svn: 304518
builtin_expect applied on && or || expressions were not
handled properly before. With this patch, the problem is fixed.
Differential Revision: http://reviews.llvm.org/D33164
llvm-svn: 304517
This was rL304226, reverted in 304228 due to a clang assertion failure
on the build bots. That problem should have been addressed by clang
commit rL304470.
llvm-svn: 304488
Replace GVFlags::LiveRoot with GVFlags::Live and use that instead of
all the DeadSymbols sets. This is refactoring in order to make
liveness information available in the RegularLTO pipeline.
llvm-svn: 304466
The lowerer wrongly assumes the ICMP instruction
1) always has a constant operand;
2) the operand has value 0.
It also assumes the expected value can only be one, thus
other values other than one will be considered 'zero'.
This leads to wrong profile annotation when other integer values
are used other than 0, 1 in the comparison or in the expect intrinsic.
Also missing is handling of equal predicate.
This patch fixes all the above problems.
Differential Revision: http://reviews.llvm.org/D33757
llvm-svn: 304453
Summary:
Sort OpsToRename before iterating to make iteration order deterministic.
Thanks to Daniel Berlin for the sorting logic.
Reviewers: dberlin, RKSimon, efriedma, davide
Reviewed By: dberlin, davide
Subscribers: sanjoy, davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D33265
llvm-svn: 304447
Summary: Also see D33429 for other ThinLTO + New PM related changes.
Reviewers: davide, chandlerc, tejohnson
Subscribers: mehdi_amini, Prazek, cfe-commits, inglorion, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D33525
llvm-svn: 304378
Summary:
Fairly straightforward patch to fill in some of the holes in the
attributes API with respect to accessing parameter/argument attributes.
The patch aims to step further towards encapsulating the
idx+FirstArgIndex pattern to access these attributes to within the
AttributeList.
Patch by Daniel Neilson!
Reviewers: rnk, chandlerc, pete, javed.absar, reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33355
llvm-svn: 304329
This reverts commit r304310.
It caused build failures in polly and mingw
due to undefined reference to
llvm::RTLIB::getMEMCPY_ELEMENT_ATOMIC.
llvm-svn: 304315
This patch does an inline expansion of memcmp.
It changes the memcmp library call into an inline expansion when the size is
known at compile time and is under a target specified threshold.
This expansion is implemented in CodeGenPrepare and expands into straight line
code. The target specifies a maximum load size and the expansion works by using
this size to load the two sources, compare, and exit early if a difference is
found. It also has a special case when the memcmp result is used in a compare
to zero equality.
Differential Revision: https://reviews.llvm.org/D28637
llvm-svn: 304313
Summary:
Expanding the loop idiom test for memcpy to also recognize unordered atomic memcpy.
The only difference for recognizing
an unordered atomic memcpy and instead of a normal memcpy is
that the loads and/or stores involved are unordered atomic operations.
Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html
Patch by Daniel Neilson!
Reviewers: reames, anna, skatkov
Reviewed By: reames
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33243
llvm-svn: 304310
r303763 caused build failures in some out-of-tree tests due to an assertion in
TTI. The original patch updated cost estimates for induction variable update
instructions marked for scalarization. However, it didn't consider that the
incoming value of an induction variable phi node could be a cast instruction.
This caused queries for cast instruction costs with a mix of vector and scalar
types. This patch includes a fix for cast instructions and the test case from
PR33193.
The fix was suggested by Jonas Paulsson <paulsson@linux.vnet.ibm.com>.
Reference: https://bugs.llvm.org/show_bug.cgi?id=33193
Original Differential Revision: https://reviews.llvm.org/D33457
llvm-svn: 304235
Summary:
In rL302576, DISubprograms gained the constraint that a !dbg attachments to functions must
have a 1:1 mapping to DISubprograms. As part of that change, the function cloning support
was adjusted to attempt to enforce this invariant during cloning. However, there
were several problems with the implementation. Part of these were fixed in rL304079.
However, there was a more fundamental problem with these changes, namely that it
bypasses the matadata value map, causing the cloned metadata to be a mix of metadata
pointing to the new suprogram (where manual code was added to fix those up) and the
old suprogram (where this was not the case). This mismatch could cause a number of
different assertion failures in the DWARF emitter. Some of these are given at
https://github.com/JuliaLang/julia/issues/22069, but some others have been observed
as well. Attempt to rectify this by partially reverting the manual DI metadata fixup,
and instead using the standard value map approach. To retain the desired semantics
of not duplicating the compilation unit and inlined subprograms, explicitly freeze
these in the value map.
Reviewers: dblaikie, aprantl, GorNishanov, echristo
Reviewed By: aprantl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33655
llvm-svn: 304226
Summary:
I believe https://reviews.llvm.org/rL302576 introduced two bugs:
1) it produces duplicate distinct variables for every: dbg.value describing the same variable.
To fix the problme I switched form getDistinct() to get() in DebugLoc.cpp: auto reparentVar = [&](DILocalVariable *Var) {
return DILocalVariable::getDistinct(
2) It passes NewFunction plain name as a linkagename parameter to Subprogram constructor. Breaks assert in:
|| DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
#
(Edit: reproducer added)
Here how https://reviews.llvm.org/rL302576 broke coroutine debug info.
Coroutine body of the original function is split into several parts by cloning and removing unneeded code.
All parts describe the original function and variables present in the original function.
For a simple case, prior to Split, original function has these two blocks:
```
PostSpill: ; preds = %AllocaSpillBB
call void @llvm.dbg.value(metadata i32 %x, i64 0, metadata !14, metadata !15), !dbg !13
store i32 %x, i32* %x.addr, align 4
...
and
sw.epilog: ; preds = %sw.bb
%x.addr.reload.addr = getelementptr inbounds %f.Frame, %f.Frame* %FramePtr, i32 0, i32 4, !dbg !20
%4 = load i32, i32* %x.addr.reload.addr, align 4, !dbg !20
call void @llvm.dbg.value(metadata i32 %4, i64 0, metadata !14, metadata !15), !dbg !13!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)
```
Note that in two blocks different expression represent the same original user variable X.
Before rL302576, for every cloned function there was exactly one cloned DILocalVariable(name: "x" as in:
```
define i8* @f(i32 %x) #0 !dbg !6 {
...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
...
!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)
define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
!28 = !DILocalVariable(name: "x", arg: 1, scope: !25, file: !7, line: 55, type: !11)
```
After rL302576, for every cloned function there were as many DILocalVariable(name: "x" as there were "call void @llvm.dbg.value" for that variable.
This was causing asserts in VerifyDebugInfo and AssemblyPrinter.
Example:
```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
!29 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!39 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!41 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
```
Second problem:
Prior to rL302576, all clones were described by DISubprogram referring to original function.
```
define i8* @f(i32 %x) #0 !dbg !6 {
...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
```
After rL302576, DISubprogram for clones is of two minds, plain name refers to the original name, linkageName refers to plain name of the clone.
```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
```
I think the assumption in AsmPrinter is that both name and linkageName should refer to the same entity. It asserts here when they are not:
```
|| DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
```
After this fix, behavior (with respect to coroutines) reverts to exactly as it was before and therefore making them debuggable again, or even more importantly, compilable, with "-g"
Reviewers: dblaikie, echristo, aprantl
Reviewed By: dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33614
llvm-svn: 304079
The recommit is to fix a bug about ExtractValue and InsertValue ops. For those
ops, some varargs inside GVN::Expression are not value numbers but raw index
numbers. It is wrong to do phi-translate for raw index numbers, and the fix is
to stop doing that.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
llvm-svn: 304050
The whole-program-devirt pass needs to run at -O0 because only it
knows about the llvm.type.checked.load intrinsic: it needs to both
lower the intrinsic itself and handle it in the summary.
Differential Revision: https://reviews.llvm.org/D33571
llvm-svn: 304019
Every other place in InstCombine that uses these methods in ValueTracking already pass this information. This makes the remaining sites consistent.
Differential Revision: https://reviews.llvm.org/D33567
llvm-svn: 304018
We have wrappers for several other ValueTracking methods that take care of passing all of the analysis and assumption cache parameters. This extends it to isKnownToBeAPowerOfTwo.
llvm-svn: 303924
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
llvm-svn: 303923
There's probably a lot more like this (see also comments in D33338 about responsibility),
but I suspect we don't usually get a visible manifestation.
Given the recent interest in improving InstCombine efficiency, another potential micro-opt
that could be repeated several times in this function: morph the existing icmp pred/operands
instead of creating a new instruction.
llvm-svn: 303860
This patch provides an initial prototype for a pass that sinks instructions based on GVN information, similar to GVNHoist. It is not yet ready for commiting but I've uploaded it to gather some initial thoughts.
This pass attempts to sink instructions into successors, reducing static
instruction count and enabling if-conversion.
We use a variant of global value numbering to decide what can be sunk.
Consider:
[ %a1 = add i32 %b, 1 ] [ %c1 = add i32 %d, 1 ]
[ %a2 = xor i32 %a1, 1 ] [ %c2 = xor i32 %c1, 1 ]
\ /
[ %e = phi i32 %a2, %c2 ]
[ add i32 %e, 4 ]
GVN would number %a1 and %c1 differently because they compute different
results - the VN of an instruction is a function of its opcode and the
transitive closure of its operands. This is the key property for hoisting
and CSE.
What we want when sinking however is for a numbering that is a function of
the *uses* of an instruction, which allows us to answer the question "if I
replace %a1 with %c1, will it contribute in an equivalent way to all
successive instructions?". The (new) PostValueTable class in GVN provides this
mapping.
This pass has some shown really impressive improvements especially for codesize already on internal benchmarks, so I have high hopes it can replace all the sinking logic in SimplifyCFG.
Differential revision: https://reviews.llvm.org/D24805
llvm-svn: 303850
pass.
The original logic only considered direct successors of the hoisted
domtree nodes, but that isn't really enough. If there are other basic
blocks that are completely within the subtree, their successors could
just as easily be impacted by the hoisting.
The more I think about it, the more I think the correct update here is
to hoist every block on the dominance frontier which has an idom in the
chain we hoist across. However, this is subtle enough that I'd
definitely appreciate some more eyes on it.
Sadly, if this is the correct algorithm, it requires computing a (highly
localized) dominance frontier. I've done this in the simplest (IE, least
code) way I could come up with, but that may be too naive. Suggestions
welcome here, dominance update algorithms are not an area I've studied
much, so I don't have strong opinions.
In good news, with this patch, turning on simple unswitch passes the
LLVM test suite for me with asserts enabled.
Differential Revision: https://reviews.llvm.org/D32740
llvm-svn: 303843
having it internally allocate the loop.
This is a much more flexible API and necessary in the new loop unswitch
to reasonably support both new and old PMs in common code. It also just
seems like a cleaner separation of concerns.
NFC, this should just be a pure refactoring.
Differential Revision: https://reviews.llvm.org/D33528
llvm-svn: 303834
Coverage instrumentation which does not instrument full post-dominators
and full-dominators may skip valid paths, as the reasoning for skipping
blocks may become circular.
This patch fixes that, by only skipping
full post-dominators with multiple predecessors, as such predecessors by
definition can not be full-dominators.
llvm-svn: 303827
Summary:
Frontend generates store instructions after allocas, for example:
```
define i8* @f(i64 %this) "coroutine.presplit"="1" personality i32 0 {
entry:
%this.addr = alloca i64
store i64 %this, i64* %this.addr
..
%hdl = call i8* @llvm.coro.begin(token %id, i8* %alloc)
```
Such instructions may require spilling into coro.frame, but, coro-frame address is only available after coro.begin and thus needs to be moved after coro.begin.
The only instructions that should not be moved are the arguments of coro.begin and all of their operands.
Reviewers: GorNishanov, majnemer
Reviewed By: GorNishanov
Subscribers: llvm-commits, EricWF
Differential Revision: https://reviews.llvm.org/D33527
llvm-svn: 303825
The swapped operands in the first test is a manifestation of an
inefficiency for vectors that doesn't exist for scalars because
the IRBuilder checks for an all-ones mask for scalars, but not
vectors.
llvm-svn: 303818
While there avoid resizing the DemandedMask twice. Make a copy into a separate variable instead. This potentially removes an allocation on large bit widths.
With the use of the zextOrTrunc methods on APInt and KnownBits these can be made almost source identical. The only difference is the zero of the upper bits for ZExt. This is similar to how its done in computeKnownBits in ValueTracking.
llvm-svn: 303791
The current code created a NewBits mask and used it as a mask several times. One of them just before a call to trunc making it unnecessary. A call to getActiveBits can get us the same information for the case. We also ORed with this mask later when we should have just sign extended the known bits.
We also called trunc on the guaranteed to be zero KnownZeros/Ones masks entering this code. Creating appropriately sized temporary APInts is probably better.
Differential Revision: https://reviews.llvm.org/D32098
llvm-svn: 303779
This continues the changes started when computeSignBit was replaced with this new version of computeKnowBits.
Differential Revision: https://reviews.llvm.org/D33431
llvm-svn: 303773
For non-uniform instructions marked for scalarization, we should update
`VectorTy` when computing instruction costs to reflect the scalar type. In
addition to determining instruction costs, this type is also used to signal
that all instructions in the loop will be scalarized. This currently affects
memory instructions and non-pointer induction variables and their updates. (We
also mark GEPs scalar after vectorization, but their cost is computed together
with memory instructions.) For scalarized induction updates, this patch also
scales the scalar cost by the vectorization factor, corresponding to each
induction step.
llvm-svn: 303763
The loop vectorizer usually vectorizes any instruction it can and then
extracts the elements for a scalarized use. On SystemZ, all elements
containing addresses must be extracted into address registers (GRs). Since
this extraction is not free, it is better to have the address in a suitable
register to begin with. By forcing address arithmetic instructions and loads
of addresses to be scalar after vectorization, two benefits result:
* No need to extract the register
* LSR optimizations trigger (LSR isn't handling vector addresses currently)
Benchmarking show improvements on SystemZ with this new behaviour.
Any other target could try this by returning false in the new hook
prefersVectorizedAddressing().
Review: Renato Golin, Elena Demikhovsky, Ulrich Weigand
https://reviews.llvm.org/D32422
llvm-svn: 303744
Otherwise we don't revisit an instruction that could be simplified,
and when we verify, we discover there's something that changed, i.e.
what we had wasn't a maximal fixpoint.
Fixes PR32836.
llvm-svn: 303715
Instead of using the SCCP homegrown one. We should eventually
make the private SCCP version disappear, but that wont' be today.
PR33143 tracks this issue.
Add braces for consistency while here. No functional change intended.
llvm-svn: 303706
Coverage instrumentation has an optimization not to instrument extra
blocks, if the pass is already "accounted for" by a
successor/predecessor basic block.
However (https://github.com/google/sanitizers/issues/783) this
reasoning may become circular, which stops valid paths from having
coverage.
In the worst case this can cause fuzzing to stop working entirely.
This change simplifies logic to something which trivially can not have
such circular reasoning, as losing valid paths does not seem like a
good trade-off for a ~15% decrease in the # of instrumented basic blocks.
llvm-svn: 303698
Summary:
Before this change, AttributeLists stored a pair of index and
AttributeSet. This is memory efficient if most arguments do not have
attributes. However, it requires doing a search over the pairs to test
an argument or function attribute. Profiling shows that this loop was
0.76% of the time in 'opt -O2' of sqlite3.c, because LLVM constantly
tests values for nullability.
This was worth about 2.5% of mid-level optimization cycles on the
sqlite3 amalgamation. Here are the full perf results:
https://reviews.llvm.org/P7995
Here are just the before and after cycle counts:
```
$ perf stat -r 5 ./opt_before -O2 sqlite3.bc -o /dev/null
13,274,181,184 cycles # 3.047 GHz ( +- 0.28% )
$ perf stat -r 5 ./opt_after -O2 sqlite3.bc -o /dev/null
12,906,927,263 cycles # 3.043 GHz ( +- 0.51% )
```
This patch *does not* change the indices used to query attributes, as
requested by reviewers. Tracking whether an index is usable for array
indexing is a huge pain that affects many of the internal APIs, so it
would be good to come back later and do a cleanup to remove this
internal adjustment.
Reviewers: pete, chandlerc
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D32819
llvm-svn: 303654
This patch builds over https://reviews.llvm.org/rL303349 and replaces
the use of the condition only if it is safe to do so.
We should not blindly RAUW the condition if experimental.guard or assume
is a use of that
condition. This is because LVI may have used the guard/assume to
identify the
value of the condition, and RUAWing will fold the guard/assume and uses
before the guards/assumes.
Reviewers: sanjoy, reames, trentxintong, mkazantsev
Reviewed by: sanjoy, reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33257
llvm-svn: 303633
The default behavior of -Rpass-analysis=loop-vectorizer is to report only the
first reason encountered for not vectorizing, if one is found, at which time the
vectorizer aborts its handling of the loop. This patch allows multiple reasons
for not vectorizing to be identified and reported, at the potential expense of
additional compile-time, under allowExtraAnalysis which can currently be turned
on by Clang's -fsave-optimization-record and opt's -pass-remarks-missed.
Removed from LoopVectorizationLegality::canVectorize() the redundant checking
and reporting if we CantComputeNumberOfIterations, as LAI::canAnalyzeLoop() also
does that. This redundancy is caught by a lit test once multiple reasons are
reported.
Patch initially developed by Dror Barak.
Differential Revision: https://reviews.llvm.org/D33396
llvm-svn: 303613
Summary:
With instrumentation profiling, when updating the VP metadata after
an inline, VP metadata on the inlined copy was inadvertantly having
all counts zeroed out. This was causing indirect calls from code inlined
during the call step to be marked as cold in the ThinLTO summaries and
not imported.
The CallerBFI needs to be passed down so that the CallSiteCount can be
computed from the profile summary info. With Sample PGO this was working
since the count is extracted from the branch weight metadata on the
call being inlined (even before we stopped looking at metadata for
non-sample PGO in r302844 this largely wasn't working for instrumentation
PGO since only promoted indirect calls would be getting inlined and have
the metadata).
Added an instrumentation PGO test and renamed the sample PGO test.
Reviewers: danielcdh, eraman
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D33389
llvm-svn: 303574
Summary:
Fix naming conventions and const correctness.
This completes the changes made in rL303029.
Patch by Yoav Ben-Shalom.
Reviewers: craig.topper
Reviewed By: craig.topper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33377
llvm-svn: 303529
Otherwise we end up miscompiling, transforming:
define i8 @tinky() {
%sext = sext i1 1 to i16
%hibit = lshr i16 %sext, 15
%tr = trunc i16 %hibit to i8
ret i8 %tr
}
into:
%sext = sext i1 1 to i8
ret i8 %sext
and the first get folded to ret i8 1, while the second gets folded
to ret i8 -1.
Eventually we should get rid of this transform entirely, but for now,
this at least fixes a know correctness bug.
Differential Revision: https://reviews.llvm.org/D33338
llvm-svn: 303513
Summary: This allows pthread_self to be pulled out of a loop by LICM.
Reviewers: hfinkel, arsenm, davide
Reviewed By: davide
Subscribers: davide, wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D32782
llvm-svn: 303495
In the case where we have an operand defined by a lod of the
same memory location. Historically this was a VariableExpression
because we wanted to make sure they ended up in the same class,
but if we create the right expression, they end up in the same
class anyway.
Fixes PR32897. Thanks to Dan for the detailed discussion and the
fix suggestion.
llvm-svn: 303475
This was here because we don't want to switch leaders too much,
in order to avoid fixpoint(ing) issue, but it's not sure if it
matters in practice.
A first step towards fixing PR32897.
llvm-svn: 303473
Refactor the strlen optimization code to work for both strlen and wcslen.
This especially helps with programs in the wild where people pass
L"string"s to const std::wstring& function parameters and the wstring
constructor gets inlined.
This also fixes a lingerind API problem/bug in getConstantStringInfo()
where zeroinitializers would always give you an empty string (without a
length) back regardless of the actual length of the initializer which
did not work well in the TrimAtNul==false causing the PR mentioned
below.
Note that the fixed getConstantStringInfo() needed fixes to SelectionDAG
memcpy lowering and may lead to some cases for out-of-bounds
zeroinitializer accesses not getting optimized anymore. So some code
with UB may produce out of bound memory reads now instead of just
producing zeros.
The refactoring "accidentally" fixes http://llvm.org/PR32124
Differential Revision: https://reviews.llvm.org/D32839
llvm-svn: 303461
This is a complicated bug involving two issues:
1. What do we do with phi nodes when we prove all arguments are not
live?
2. When is it safe to use value leaders to determine if we can ignore
an argumnet?
llvm-svn: 303453
Summary:
NewGVN: Handle equivalence between phi of ops and op of phis.
This makes our GVN mostly-complete. It would be complete, modulo some
deliberate choices we make. This means it detects roughly all herband
equivalences in polynomial time, including cases notoriously hard for
other GVN's to detect. It also detects a very large swath of the
cases we currently rely on instcombine to detect that involve folding
upwards through phis.
Fixes PR 31125, 31463, PR 31868
Reviewers: davide
Subscribers: Prazek, llvm-commits
Differential Revision: https://reviews.llvm.org/D32151
llvm-svn: 303444
Summary:
This NFC simply refactors the return value of LoopIdiomRecognize::isLegalStore() from bool to an enumeration, and
removes the return-through-parameter mechanism that the function was using. This function is constructed such that it will
only ever recognize a single store idiom (memset, memset_pattern, or memcpy), and never a combination of these. As such it
makes much more sense for the return value to be the single idiom that the store matches, rather than
having a separate argument-return for each idiom -- it's cleaner, and makes it clearer that
only a single idiom can be matched.
Patch by Daniel Neilson!
Reviewers: anna, sanjoy, davide, haicheng
Reviewed By: anna, haicheng
Subscribers: haicheng, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D33359
llvm-svn: 303434
We can have cycles between PHIs and this causes singleReachablePhi()
to call itself indefintely (until we run out of stack). The proper
solution would be that of computing SCCs, but it's not worth for
now, so just keep a visited set and give up when we find a cycle.
Thanks to Dan for the discussion/help with this.
Fixes PR33014.
llvm-svn: 303393
Also, fix the old-style capitalization of the related functions
and move them to the 'private' section of the class since they
are just helpers of the visit* functions.
As shown in the post-commit comments for D32143, we are missing
folds for xor-of-icmps.
llvm-svn: 303381
Summary:
Implements PR889
Removing the virtual table pointer from Value saves 1% of RSS when doing
LTO of llc on Linux. The impact on time was positive, but too noisy to
conclusively say that performance improved. Here is a link to the
spreadsheet with the original data:
https://docs.google.com/spreadsheets/d/1F4FHir0qYnV0MEp2sYYp_BuvnJgWlWPhWOwZ6LbW7W4/edit?usp=sharing
This change makes it invalid to directly delete a Value, User, or
Instruction pointer. Instead, such code can be rewritten to a null check
and a call Value::deleteValue(). Value objects tend to have their
lifetimes managed through iplist, so for the most part, this isn't a big
deal. However, there are some places where LLVM deletes values, and
those places had to be migrated to deleteValue. I have also created
llvm::unique_value, which has a custom deleter, so it can be used in
place of std::unique_ptr<Value>.
I had to add the "DerivedUser" Deleter escape hatch for MemorySSA, which
derives from User outside of lib/IR. Code in IR cannot include MemorySSA
headers or call the MemoryAccess object destructors without introducing
a circular dependency, so we need some level of indirection.
Unfortunately, no class derived from User may have any virtual methods,
because adding a virtual method would break User::getHungOffOperands(),
which assumes that it can find the use list immediately prior to the
User object. I've added a static_assert to the appropriate OperandTraits
templates to help people avoid this trap.
Reviewers: chandlerc, mehdi_amini, pete, dberlin, george.burgess.iv
Reviewed By: chandlerc
Subscribers: krytarowski, eraman, george.burgess.iv, mzolotukhin, Prazek, nlewycky, hans, inglorion, pcc, tejohnson, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D31261
llvm-svn: 303362
The testcase in PR33077 generates a LSR Use Formula with two SCEVAddRecExprs for the same
loop. Such uncommon formula will become non-canonical after GenerateTruncates adds sign
extension to the ScaledReg of the Formula, and it will break the assertion that every
Formula to be inserted is canonical.
The fix is to call canonicalize for the raw Formula generated by GenerateTruncates
before inserting it.
llvm-svn: 303361
Summary:
We have a bug when RAUWing the condition if experimental.guard or assumes is a use of that
condition. This is because LazyValueInfo may have used the guards/assumes to identify the
value of the condition at the end of the block. RAUW replaces the uses
at the guard/assume as well as uses before the guard/assume. Both of
these are incorrect.
For now, disable RAUW for conditions and fix the logic as a next
step: https://reviews.llvm.org/D33257
Reviewers: sanjoy, reames, trentxintong
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33279
llvm-svn: 303349
Summary:
There are several places in the codebase that try to calculate a maximum value in a Statistic object. We currently do this in one of two ways:
MaxNumFoo = std::max(MaxNumFoo, NumFoo);
or
MaxNumFoo = (MaxNumFoo > NumFoo) ? MaxNumFoo : NumFoo;
The first version reads from MaxNumFoo one time and uncontionally rwrites to it. The second version possibly reads it twice depending on the result of the first compare. But we have no way of knowing if the value was changed by another thread between the reads and the writes.
This patch adds a method to the Statistic object that can ensure that we only store if our value is the max and the previous max didn't change after we read it. If it changed we'll recheck if our value should still be the max or not and try again.
This spawned from an audit I'm trying to do of all places we uses the implicit conversion to unsigned on the Statistics objects. See my previous thread on llvm-dev https://groups.google.com/forum/#!topic/llvm-dev/yfvxiorKrDQ
Reviewers: dberlin, chandlerc, hfinkel, dblaikie
Reviewed By: chandlerc
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D33301
llvm-svn: 303318
I believe this technically fixes a multithreaded race condition in this code. But my primary concern was as part of looking at removing the ability to treat Statistics like a plain unsigned. There are many weird operations on Statistics in the codebase.
llvm-svn: 303314
The missing optimization for xor-of-icmps still needs to be added, but by
being more efficient (not generating unnecessary logic ops with constants)
we avoid the bug.
See discussion in post-commit comments:
https://reviews.llvm.org/D32143
llvm-svn: 303312
As noted in the post-commit comments in D32143, we should be
catching the constant operand cases sooner to be more efficient
and less likely to expose a missing fold.
llvm-svn: 303309
There should be a slight efficiency improvement from handling icmp/fcmp with one matcher and reducing duplicated code.
The larger motivation is that there are questions about how predicate canonicalization is handled, and the refactoring
should make it easier if we want to change any of that behavior.
1. As noted in the code comment, we've chosen 3 of the 16 FCMP preds as not canonical. Why those 3? It goes back to
rL32751 from what I can tell, but I'm not sure if there's a justification for that rule.
2. We currently do not canonicalize integer select conditions. Should we use the same rule that applies to branches
for selects?
3. We currently do canonicalize some FP select conditions, and those rules would conflict with the rule shown here.
Should one or both be changed?
No-functional-change-intended, but adding tests anyway because there's no coverage for most of the predicates.
Differential Revision: https://reviews.llvm.org/D33247
llvm-svn: 303261
If we need to spill the result of the PHI instruction, we insert the spill after
all of the PHIs and EHPads, however, in a catchswitch block there is no
room to insert the spill. Make room by splitting away catchswitch into a separate
block.
Before the fix:
catch.dispatch:
%val = phi i32 [ 1, %if.then ], [ 2, %if.else ]
%switch = catchswitch within none [label %catch] unwind label %cleanuppad
After:
catch.dispatch:
%val = phi i32 [ 1, %if.then ], [ 2, %if.else ]
%tok = cleanuppad within none []
; spill goes here
cleanupret from %tok unwind label %catch.dispatch.switch
catch.dispatch.switch:
%switch = catchswitch within none [label %catch] unwind label %cleanuppad
https://reviews.llvm.org/D31846
llvm-svn: 303232
CTLZ idiom recognition (r303102).
Summary:
The following case:
i = 1;
if(n)
while (n >>= 1)
i++;
use(i);
Was converted to:
i = 1;
if(n)
i += builtin_ctlz(n >> 1, false);
use(i);
Which is not correct. The patch make it:
i = 1;
if(n)
i += builtin_ctlz(n >> 1, true);
use(i);
From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 303212
Summary:
RewritePHIs algorithm used in building of CoroFrame inserts a placeholder
```
%placeholder = phi [%val]
```
on every edge leading to a block starting with PHI node with multiple incoming edges,
so that if one of the incoming values was spilled and need to be reloaded, we have a
place to insert a reload. We use SplitEdge helper function to split the incoming edge.
SplitEdge function does not deal with unwind edges comping into a block with an EHPad.
This patch adds an ehAwareSplitEdge function that can correctly split the unwind edge.
For landing pads, we clone the landing pad into every edge block and replace the original
landing pad with a PHI collection the values from all incoming landing pads.
For WinEH pads, we keep the original EHPad in place and insert cleanuppad/cleapret in the
edge blocks.
Reviewers: majnemer, rnk
Reviewed By: majnemer
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D31845
llvm-svn: 303172
This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.
Differential Revision: https://reviews.llvm.org/D33162
llvm-svn: 303134
There's no need (& a bit incorrect) to mask off the high bits of the
register reference when describing a simple bool value.
Reviewers: aprantl
Differential Revision: https://reviews.llvm.org/D31062
llvm-svn: 303117
ARM Neon has native support for half-sized vector registers (64 bits). This
is beneficial for example for 2D and 3D graphics. This patch adds the option
to lower MinVecRegSize from 128 via a TTI in the SLP Vectorizer.
*** Performance Analysis
This change was motivated by some internal benchmarks but it is also
beneficial on SPEC and the LLVM testsuite.
The results are with -O3 and PGO. A negative percentage is an improvement.
The testsuite was run with a sample size of 4.
** SPEC
* CFP2006/482.sphinx3 -3.34%
A pretty hot loop is SLP vectorized resulting in nice instruction reduction.
This used to be a +22% regression before rL299482.
* CFP2000/177.mesa -3.34%
* CINT2000/256.bzip2 +6.97%
My current plan is to extend the fix in rL299482 to i16 which brings the
regression down to +2.5%. There are also other problems with the codegen in
this loop so there is further room for improvement.
** LLVM testsuite
* SingleSource/Benchmarks/Misc/ReedSolomon -10.75%
There are multiple small SLP vectorizations outside the hot code. It's a bit
surprising that it adds up to 10%. Some of this may be code-layout noise.
* MultiSource/Benchmarks/VersaBench/beamformer/beamformer -8.40%
The opt-viewer screenshot can be seen at F3218284. We start at a colder store
but the tree leads us into the hottest loop.
* MultiSource/Applications/lambda-0.1.3/lambda -2.68%
* MultiSource/Benchmarks/Bullet/bullet -2.18%
This is using 3D vectors.
* SingleSource/Benchmarks/Shootout-C++/Shootout-C++-lists +6.67%
Noise, binary is unchanged.
* MultiSource/Benchmarks/Ptrdist/anagram/anagram +4.90%
There is an additional SLP in the cold code. The test runs for ~1sec and
prints out over 2000 lines. This is most likely noise.
* MultiSource/Applications/aha/aha +1.63%
* MultiSource/Applications/JM/lencod/lencod +1.41%
* SingleSource/Benchmarks/Misc/richards_benchmark +1.15%
Differential Revision: https://reviews.llvm.org/D31965
llvm-svn: 303116
Summary:
The following loops should be recognized:
i = 0;
while (n) {
n = n >> 1;
i++;
body();
}
use(i);
And replaced with builtin_ctlz(n) if body() is empty or
for CPUs that have CTLZ instruction converted to countable:
for (j = 0; j < builtin_ctlz(n); j++) {
n = n >> 1;
i++;
body();
}
use(builtin_ctlz(n));
Reviewers: rengolin, joerg
Differential Revision: http://reviews.llvm.org/D32605
From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 303102
verifyMemoryCongruency() filters out trivially dead MemoryDef(s),
as we find them immediately dead, before moving from TOP to a new
congruence class.
This fixes the same problem for PHI(s) skipping MemoryPhis if all
the operands are dead.
Differential Revision: https://reviews.llvm.org/D33044
llvm-svn: 303100
Summary:
Merge overflow computation for signed add,
appearing both in InstCombine and ValueTracking.
As part of the merge,
cleanup the interface for overflow checks in InstCombine.
Patch by Yoav Ben-Shalom.
Reviewers: craig.topper, majnemer
Reviewed By: craig.topper
Subscribers: takuto.ikuta, llvm-commits
Differential Revision: https://reviews.llvm.org/D32946
llvm-svn: 303029
Summary:
If the Worklist build causes an IR change this change flag currently factors into the flag for running another iteration of the iteration loop. But only changes during processing should trigger another loop.
This patch captures the worklist creation change flag into the outside the loop flag currently used for DbgDeclares and only sends that flag up to the caller. Rerunning the loop only depends on IC.run() now.
This uses the debug output of InstCombine to determine if one or two iterations run. I couldn't think of a better way to detect it since the second spurious iteration shoudn't make any visible changes. Just wasted computation.
I can do a pre-commit of the test case with the CHECK-NOT as a CHECK if this is an ok way to check this.
This is a subset of D31678 as I'm still not sure how to verify the analysis behavior for that.
Reviewers: davide, majnemer, spatel, chandlerc
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32453
llvm-svn: 302982
Implemented frequency based cost/saving analysis
and related options.
The pass is now in a state ready to be turne on
in the pipeline (in follow up).
Differential Revision: http://reviews.llvm.org/D32783
llvm-svn: 302967
This patch adds min/max population count, leading/trailing zero/one bit counting methods.
The min methods return answers based on bits that are known without considering unknown bits. The max methods give answers taking into account the largest count that unknown bits could give.
Differential Revision: https://reviews.llvm.org/D32931
llvm-svn: 302925
This code was missing a check for stores, so we were thinking the
congruency class didn't have any memory members, and reset the
memory leader.
Differential Revision: https://reviews.llvm.org/D33056
llvm-svn: 302905
invariant PHI inputs and to rewrite PHI nodes during the actual
unswitching.
The checking is quite easy, but rewriting the PHI nodes is somewhat
surprisingly challenging. This should handle both branches and switches.
I think this is now a full featured trivial unswitcher, and more full
featured than the trivial cases in the old pass while still being (IMO)
somewhat simpler in how it works.
Next up is to verify its correctness in more widespread testing, and
then to add non-trivial unswitching.
Thanks to Davide and Sanjoy for the excellent review. There is one
remaining question that I may address in a follow-up patch (see the
review thread for details) but it isn't related to the functionality
specifically.
Differential Revision: https://reviews.llvm.org/D32699
llvm-svn: 302867
The approach I followed was to emit the remark after getTreeCost concludes
that SLP is profitable. I initially tried emitting them after the
vectorizeRootInstruction calls in vectorizeChainsInBlock but I vaguely
remember missing a few cases for example in HorizontalReduction::tryToReduce.
ORE is placed in BoUpSLP so that it's available from everywhere (notably
HorizontalReduction::tryToReduce).
We use the first instruction in the root bundle as the locator for the remark.
In order to get a sense how far the tree is spanning I've include the size of
the tree in the remark. This is not perfect of course but it gives you at
least a rough idea about the tree. Then you can follow up with -view-slp-tree
to really see the actual tree.
llvm-svn: 302811
Introduce LoopVectorizationPlanner.executePlan(), replacing ILV.vectorize() and
refactoring ILV.vectorizeLoop(). Method collectDeadInstructions() is moved from
ILV to LVP. These changes facilitate building VPlans and using them to generate
code, following https://reviews.llvm.org/D28975 and its tentative breakdown.
Method ILV.createEmptyLoop() is renamed ILV.createVectorizedLoopSkeleton() to
improve clarity; it's contents remain intact.
Differential Revision: https://reviews.llvm.org/D32200
llvm-svn: 302790
It turned out that MSan was incorrectly calculating the shadow for int comparisons: it was done by truncating the result of (Shadow1 OR Shadow2) to i1, effectively rendering all bits except LSB useless.
This approach doesn't work e.g. in the case where the values being compared are even (i.e. have the LSB of the shadow equal to zero).
Instead, if CreateShadowCast() has to cast a bigger int to i1, we replace the truncation with an ICMP to 0.
This patch doesn't affect the code generated for SPEC 2006 binaries, i.e. there's no performance impact.
For the test case reported in PR32842 MSan with the patch generates a slightly more efficient code:
orq %rcx, %rax
jne .LBB0_6
, instead of:
orl %ecx, %eax
testb $1, %al
jne .LBB0_6
llvm-svn: 302787
// (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
This canonicalization was added at:
https://reviews.llvm.org/rL7264
By moving xors out/down, we can more easily combine constants. I'm adding
tests that do not change with this patch, so we can verify that those kinds
of transforms are still happening.
This is no-functional-change-intended because there's a later fold:
// (X^C)|Y -> (X|Y)^C iff Y&C == 0
...and demanded-bits appears to guarantee that any fold that would have
hit the fold we're removing here would be caught by that 2nd fold.
Similar reasoning was used in:
https://reviews.llvm.org/rL299384
The larger motivation for removing this code is that it could interfere with
the fix for PR32706:
https://bugs.llvm.org/show_bug.cgi?id=32706
Ie, we're not checking if the 'xor' is actually a 'not', so we could reverse
a 'not' optimization and cause an infinite loop by altering an 'xor X, -1'.
Differential Revision: https://reviews.llvm.org/D33050
llvm-svn: 302733
This fixes a ubsan bot failure after r302597, which made getProfileCount
non-static, but ended up invoking it on a null ProfileSummaryInfo object
in some cases from buildModuleSummaryIndex.
Most testing passed because the non-static getProfileCount currently
doesn't access any member variables, but I found this when testing a
follow on patch (D32877) that adds a member variable access.
llvm-svn: 302705
This is another step towards favoring 'not' ops over random 'xor' in IR:
https://bugs.llvm.org/show_bug.cgi?id=32706
This transformation may have occurred in longer IR sequences using computeKnownBits,
but that could be much more expensive to calculate.
As the scalar result shows, we do not currently favor 'not' in all cases. The 'not'
created by the transform is transformed again (unnecessarily). Vectors don't have
this problem because vectors are (wrongly) excluded from several other combines.
llvm-svn: 302659
This pass doesn't correctly handle testing for when it is legal to hoist
arbitrary instructions. The whitelist happens to make it safe, so before
it is removed the pass's legality checks will need to be enhanced.
Details have been added to the code review thread for the patch.
llvm-svn: 302640
This pass uses a new target hook to decide whether or not to expand a particular
intrinsic to the shuffevector sequence.
Differential Revision: https://reviews.llvm.org/D32245
llvm-svn: 302631
This change is required because the notion of count is different for
sample profiling and getProfileCount will need to determine the
underlying profile type.
Differential revision: https://reviews.llvm.org/D33012
llvm-svn: 302597
Summary:
This fixes the immediate crash caused by introducing an incorrect inttoptr
before attempting the conversion. There may still be a legality
check missing somewhere earlier for non-integral pointers, but this change
seems necessary in any case.
Reviewers: sanjoy, dberlin
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32623
llvm-svn: 302587
The AArch64 instruction set has a few "widening" instructions (e.g., uaddl,
saddl, uaddw, etc.) that take one or more doubleword operands and produce
quadword results. The operands are automatically sign- or zero-extended as
appropriate. However, in LLVM IR, these extends are explicit. This patch
updates TTI to consider these widening instructions as single operations whose
cost is attached to the arithmetic instruction. It marks extends that are part
of a widening operation "free" and applies a sub-target specified overhead
(zero by default) to the arithmetic instructions.
Differential Revision: https://reviews.llvm.org/D32706
llvm-svn: 302582
The motivation for getting rid of dyn_castNotVal is to allow fixing:
https://bugs.llvm.org/show_bug.cgi?id=32706
So this was supposed to be functional-change-intended for the case
of inverting constants and applying DeMorgan. However, I can't find
any cases where that pattern will actually get to matchDeMorgansLaws()
because we have other folds in visitAnd/visitOr that do the same
thing. So this ends up just being a clean-up patch with slight efficiency
improvement, but no-functional-change-intended.
llvm-svn: 302581
As recently discussed on llvm-dev [1], this patch makes it illegal for
two Functions to point to the same DISubprogram and updates
FunctionCloner to also clone the debug info of a function to conform
to the new requirement. To simplify the implementation it also factors
out the creation of inlineAt locations from the Inliner into a
general-purpose utility in DILocation.
[1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
<rdar://problem/31926379>
Differential Revision: https://reviews.llvm.org/D32975
This reapplies r302469 with a fix for a bot failure (reparentDebugInfo
now checks for the case the orig and new function are identical).
llvm-svn: 302576
Summary:
Since I will post patch with some changes to
replaceDominatedUsesWith, it would be good to avoid
duplicating code again.
Reviewers: davide, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32798
llvm-svn: 302575
Use variadic templates instead of relying on <cstdarg> + sentinel.
This enforces better type checking and makes code more readable.
Differential Revision: https://reviews.llvm.org/D32541
llvm-svn: 302571
The way we currently define congruency for two PHIExpression(s) is:
1) The operands to the phi functions are congruent
2) The PHIs are defined in the same BasicBlock.
NewGVN works under the assumption that phi operands are in predecessor
order, or at least in some consistent order. OTOH, is valid IR:
patatino:
%meh = phi i16 [ %0, %winky ], [ %conv1, %tinky ]
%banana = phi i16 [ %0, %tinky ], [ %conv1, %winky ]
br label %end
and the in-memory representations of the two SSA registers have an
inconsistent order. This violation of NewGVN assumptions results into
two PHIs found congruent when they're not. While we think it's useful
to have always a consistent order enforced, let's fix this in NewGVN
sorting uses in predecessor order before creating a PHI expression.
Differential Revision: https://reviews.llvm.org/D32990
llvm-svn: 302552
The comment says to avoid the case where zero bits are shifted into the truncated value,
but the code checks that the shift is smaller than the truncated value instead of the
number of bits added by the sign extension. Fixing this allows a shift by more than the
value size to be introduced, which is undefined behavior, so the shift is capped at the
value size minus one, which has the expected behavior of filling the value with the sign
bit.
Patch by Jacob Young!
Differential Revision: https://reviews.llvm.org/D32285
llvm-svn: 302548
This caused PR32977.
Original commit message:
> Make it illegal for two Functions to point to the same DISubprogram
>
> As recently discussed on llvm-dev [1], this patch makes it illegal for
> two Functions to point to the same DISubprogram and updates
> FunctionCloner to also clone the debug info of a function to conform
> to the new requirement. To simplify the implementation it also factors
> out the creation of inlineAt locations from the Inliner into a
> general-purpose utility in DILocation.
>
> [1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
> <rdar://problem/31926379>
>
> Differential Revision: https://reviews.llvm.org/D32975
llvm-svn: 302533
Summary:
In first order recurrence vectorization, when the previous value is a phi node, we need to
set the insertion point to the first non-phi node.
We can have the previous value being a phi node, due to the generation of new
IVs as part of trunc optimization [1].
[1] https://reviews.llvm.org/rL294967
Reviewers: mssimpso, mkuper
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D32969
llvm-svn: 302532
- This change allows targets to opt-in to using them instead of the log2
shufflevector algorithm.
- The SLP and Loop vectorizers have the common code to do shuffle reductions
factored out into LoopUtils, and now have a unified interface for generating
reductions regardless of the preference of the target. LoopUtils now uses TTI
to determine what kind of reductions the target wants to handle.
- For CodeGen, basic legalization support is added.
Differential Revision: https://reviews.llvm.org/D30086
llvm-svn: 302514
As recently discussed on llvm-dev [1], this patch makes it illegal for
two Functions to point to the same DISubprogram and updates
FunctionCloner to also clone the debug info of a function to conform
to the new requirement. To simplify the implementation it also factors
out the creation of inlineAt locations from the Inliner into a
general-purpose utility in DILocation.
[1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
<rdar://problem/31926379>
Differential Revision: https://reviews.llvm.org/D32975
llvm-svn: 302469
This is another step towards getting rid of dyn_castNotVal,
so we can recommit:
https://reviews.llvm.org/rL300977
As the tests show, we were missing the lshr case for constants
and both ashr/lshr vector splat folds. The ashr case with constant
was being performed inefficiently in 2 steps. It's also possible
there was a latent bug in that case because we can't do that fold
if the constant is positive:
http://rise4fun.com/Alive/Bge
llvm-svn: 302465
Previously SimplifyCFG used getSetSize which returns an APInt that is 1 bit wider than the ConstantRange's bit width. In the reasonably common case that the ConstantRange is 64-bits wide, this requires returning a 65-bit APInt. APInt's can only store 64-bits without a memory allocation so this is inefficient.
The new method takes the 8 as an input and tells if the range contains more than that many elements without requiring any wider math.
llvm-svn: 302385
We can simplify (or (icmp X, C1), (icmp X, C2)) to 'true' or one of the icmps in many cases.
I had to check some of these with Alive to prove to myself it's right, but everything seems
to check out. Eg, the deleted code in instcombine was completely ignoring predicates with
mismatched signedness.
This is a follow-up to:
https://reviews.llvm.org/rL301260https://reviews.llvm.org/D32143
llvm-svn: 302370
wcslen is part of the C99 and C++98 standards.
- This introduces the function to TargetLibraryInfo.
- Also set attributes for wcslen in llvm::inferLibFuncAttributes().
Differential Revision: https://reviews.llvm.org/D32837
llvm-svn: 302278
This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown.
Differential Revision: https://reviews.llvm.org/D32637
llvm-svn: 302262
Loop Idiom recognition was generating memset in a case that
would result generating a division operation to an unsafe location.
Differential Revision: https://reviews.llvm.org/D32674
llvm-svn: 302238
Compares always return a scalar integer or vector of integers. isIntegerTy returns false for vectors, but that's not completely obvious. So using isVectorTy is less confusing.
llvm-svn: 302198
This fixes a regression since SVN rev 273808 (which was supposed to
not change functionality).
The regression caused miscompilations (noted in the wild when targeting
AArch64) on platforms with 32 bit long.
Differential Revision: https://reviews.llvm.org/D32850
llvm-svn: 302137
When profiling a no-op incremental link of Chromium I found that the functions
computeImportForFunction and computeDeadSymbols were consuming roughly 10% of
the profile. The goal of this change is to improve the performance of those
functions by changing the map lookups that they were previously doing into
pointer dereferences.
This is achieved by changing the ValueInfo data structure to be a pointer to
an element of the global value map owned by ModuleSummaryIndex, and changing
reference lists in the GlobalValueSummary to hold ValueInfos instead of GUIDs.
This means that a ValueInfo will take a client directly to the summary list
for a given GUID.
Differential Revision: https://reviews.llvm.org/D32471
llvm-svn: 302108
Change checkRippleForAdd from a heuristic to a full check -
if it is provable that the add does not overflow return true, otherwise false.
Patch by Yoav Ben-Shalom
Differential Revision: https://reviews.llvm.org/D32686
llvm-svn: 302093
This patch adds isConstant and getConstant for determining if KnownBits represents a constant value and to retrieve the value. Use them to simplify code.
Differential Revision: https://reviews.llvm.org/D32785
llvm-svn: 302091
This patch adds zext, sext, and trunc methods to KnownBits and uses them where possible.
Differential Revision: https://reviews.llvm.org/D32784
llvm-svn: 302088
Summary:
Do three things to help with that:
- Add AttributeList::FirstArgIndex, which is an enumerator currently set
to 1. It allows us to change the indexing scheme with fewer changes.
- Add addParamAttr/removeParamAttr. This just shortens addAttribute call
sites that would otherwise need to spell out FirstArgIndex.
- Remove some attribute-specific getters and setters from Function that
take attribute list indices. Most of these were only used from
BuildLibCalls, and doesNotAlias was only used to test or set if the
return value is malloc-like.
I'm happy to split the patch, but I think they are probably easier to
review when taken together.
This patch should be NFC, but it sets the stage to change the indexing
scheme to this, which is more convenient when indexing into an array:
0: func attrs
1: retattrs
2...: arg attrs
Reviewers: chandlerc, pete, javed.absar
Subscribers: david2050, llvm-commits
Differential Revision: https://reviews.llvm.org/D32811
llvm-svn: 302060
Summary:
Cloning basic blocks in the loop for runtime loop unroller depends on loop being
in rotated form (i.e. loop latch target is the exit block).
Assert that this is true, so that callers of runtime loop unroller pass in
canonical loops.
The single caller of this function has that check recently added:
https://reviews.llvm.org/rL301239
Reviewers: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32801
llvm-svn: 302058
Summary:
Currently, loop deletion deletes loop where the only values
that are used outside the loop are loop-invariant.
This patch adds logic to delete loops where the loop is proven to be
never executed (i.e. the only predecessor of the loop preheader has a
constant conditional branch as terminator, and the preheader is not the
taken target). This will remove loops that become dead after
loop-unswitching generates constant conditional branches.
The next steps are:
1. moving the loop deletion implementation to LoopUtils.
2. Add logic in loop-simplifyCFG which will support changing conditional
constant branches to unconditional branches. If loops become unreachable in this
process, they can be removed using `deleteDeadLoop` function.
Reviewers: chandlerc, efriedma, sanjoy, reames
Reviewed by: sanjoy
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D32494
llvm-svn: 302015
This was originally checked in here:
https://reviews.llvm.org/rL301923
And reverted here:
https://reviews.llvm.org/rL301924
Because there's a clang test that would fail after this. I fixed/removed the
offending CHECK lines in:
https://reviews.llvm.org/rL301928
So let's try this again. Original commit message:
This is the fold that causes the infinite loop in BoringSSL
(https://github.com/google/boringssl/blob/master/crypto/cipher/e_rc2.c)
when we fix instcombine demanded bits to prefer 'not' ops as in https://reviews.llvm.org/D32255.
There are 2 or 3 problems with dyn_castNotVal, and I don't think we can
reinstate https://reviews.llvm.org/D32255 until dyn_castNotVal is completely eliminated.
1. As shown here, it transforms 'not' into random xor. This transform is harmful to SCEV and codegen because 'not' can often be folded while random xor cannot.
2. It does not transform vector constants. This is actually a good thing, but if you don't believe the above argument, then we shouldn't have excluded vectors.
3. It tries to avoid transforming not(not(X)). That's nice, but it doesn't match the greedy nature of instcombine. If we DeMorganize a pattern that has an extra 'not' in it: ~(~(~X) & Y) --> (~X | ~Y)
That's just another case of DeMorgan, so we should trust that we'll fold that pattern too: (~X | ~ Y) --> ~(X & Y)
Differential Revision: https://reviews.llvm.org/D32665
llvm-svn: 301929
This is the fold that causes the infinite loop in BoringSSL
(https://github.com/google/boringssl/blob/master/crypto/cipher/e_rc2.c)
when we fix instcombine demanded bits to prefer 'not' ops as in D32255.
There are 2 or 3 problems with dyn_castNotVal, and I don't think we can
reinstate D32255 until dyn_castNotVal is completely eliminated.
1. As shown here, it transforms 'not' into random xor. This transform is
harmful to SCEV and codegen because 'not' can often be folded while
random xor cannot.
2. It does not transform vector constants. This is actually a good thing,
but if you don't believe the above argument, then we shouldn't have
excluded vectors.
3. It tries to avoid transforming not(not(X)). That's nice, but it doesn't
match the greedy nature of instcombine. If we DeMorganize a pattern
that has an extra 'not' in it:
~(~(~X) & Y) --> (~X | ~Y)
That's just another case of DeMorgan, so we should trust that we'll fold
that pattern too:
(~X | ~ Y) --> ~(X & Y)
Differential Revision: https://reviews.llvm.org/D32665
llvm-svn: 301923
In the testcase attached, we believe %tmp1 implies %tmp4.
where:
br i1 %tmp1, label %bb2, label %bb7
br i1 %tmp4, label %bb5, label %bb7
because Wwhile looking at PredicateInfo stuffs we end up calling
isImpliedTrueByMatchingCmp() with the arguments backwards.
Differential Revision: https://reviews.llvm.org/D32718
llvm-svn: 301849
If we have ~(~X & Y), it only makes sense to transform it to (X | ~Y) when we do not need
the intermediate (~X & Y) value. In that case, we would need an extra instruction to
generate ~Y + 'or' (as shown in the test changes).
It's ok if we have multiple uses of ~X or Y, however. In those cases, we may not reduce the
instruction count or critical path, but we might improve throughput because we can generate
~X and ~Y in parallel. Whether that actually makes perf sense or not for a target is something
we can't answer in IR.
Differential Revision: https://reviews.llvm.org/D32703
llvm-svn: 301848
We may not be able to rewrite indirect branch target, but we also want to take it into
account when folding, i.e. if it and all its successor's predecessors go to the same
destination, we can fold, i.e. no need to thread.
llvm-svn: 301816
Summary: [JumpThread] Do RAUW in case Cond folds to a constant in the CFG
Reviewers: sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32407
llvm-svn: 301804
Summary:
programUndefinedIfPoison makes more sense, given what the function
does; and I'm about to add a function with a name similar to
isKnownNotFullPoison (so do the rename to avoid confusion).
Reviewers: broune, majnemer, bjarke.roune
Reviewed By: broune
Subscribers: mcrosier, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D30444
llvm-svn: 301776
Summary: This patch adds isNegative, isNonNegative for querying whether the sign bit is known. It also adds makeNegative and makeNonNegative for controlling the sign bit.
Reviewers: RKSimon, spatel, davide
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32651
llvm-svn: 301747
retainAutoreleasedReturnValue that retains the returned value.
This commit fixes a bug in ARC optimizer where it moves a release
between a call and a retainAutoreleasedReturnValue, causing the returned
object to be released before the retainAutoreleasedReturnValue can
retain it.
This commit accomplishes that by doing a lookahead and checking whether
the call prevents the release from moving upwards. In the long term, we
should treat the region between the retainAutoreleasedReturnValue and
the call as a critical section and disallow moving anything there
(possibly using operand bundles).
rdar://problem/20449878
llvm-svn: 301724
I fixed my miscompile in r301722 and I hope I don't have to take
a look at this code again now that Chandler has a new LoopUnswitch
pass, but maybe this could be of use for somebody else in the
meanwhile.
llvm-svn: 301723
This broke the Clang build. (Clang-side patch missing?)
Original commit message:
> [IR] Make add/remove Attributes use AttrBuilder instead of
> AttributeList
>
> This change cleans up call sites and avoids creating temporary
> AttributeList objects.
>
> NFC
llvm-svn: 301712
While looking at pure addressing expressions, it's possible
for the value to appear later in Postorder.
I haven't been able to come up with a testcase where this
exhibits an actual issue, but if you insert a dump before
the value map lookup, a few testcases crash.
llvm-svn: 301705
Eliminates some more cases where some subset of the addressing
computation remains flat. Some cases with addrspacecasts
in nested constant expressions are still left behind however.
llvm-svn: 301704
While debugging a miscompile I realized loopunswitch doesn't
put newlines when printing the instruction being replacement.
Ending up with a single line with many instruction replaced isn't
the best for readability and/or mental sanity.
llvm-svn: 301692
The method is called "get *Param* Alignment", and is only used for
return values exactly once, so it should take argument indices, not
attribute indices.
Avoids confusing code like:
IsSwiftError = CS->paramHasAttr(ArgIdx, Attribute::SwiftError);
Alignment = CS->getParamAlignment(ArgIdx + 1);
Add getRetAlignment to handle the one case in Value.cpp that wants the
return value alignment.
This is a potentially breaking change for out-of-tree backends that do
their own call lowering.
llvm-svn: 301682
This eliminates many extra 'Idx' induction variables in loops over
arguments in CodeGen/ and Target/. It also reduces the number of places
where we assume that ReturnIndex is 0 and that we should add one to
argument numbers to get the corresponding attribute list index.
NFC
llvm-svn: 301666
Summary:
Skip memops if the total value profiled count is 0, we can't correctly
scale up the counts and there is no point anyway.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32624
llvm-svn: 301645
This is a follow up to the fix in r298360 to improve the handling of debug
values when redundant LEAs are removed. The fix in r298360 effectively
discarded the debug values. This patch now attempts to preserve the debug
values by using the DWARF DW_OP_stack_value operation via prependDIExpr.
Moved functions appendOffset and prependDIExpr from Local.cpp to
DebugInfoMetadata.cpp and made them available as static member functions of
DIExpression.
Differential Revision: https://reviews.llvm.org/D31604
llvm-svn: 301630
EarlyCSE should not just ignore assumes. It should use the fact that its condition is true for all dominated instructions.
Reviewers: sanjoy, reames, apilipenko, anna, skatkov
Reviewed By: reames, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32482
llvm-svn: 301625
If a condition is calculated only once, and there are multiple guards on this condition, we should be able
to remove all guards dominated by the first of them. This patch allows EarlyCSE to try to find the condition
of a guard among the known values, and if it is true, remove the guard. Otherwise we keep the guard and
mark its condition as 'true' for future consideration.
Reviewers: sanjoy, reames, apilipenko, skatkov, anna, dberlin
Reviewed By: reames, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32476
llvm-svn: 301623
Use a combination of !associated, comdat, @llvm.compiler.used and
custom sections to allow dead stripping of globals and their asan
metadata. Sometimes.
Currently this works on LLD, which supports SHF_LINK_ORDER with
sh_link pointing to the associated section.
This also works on BFD, which seems to treat comdats as
all-or-nothing with respect to linker GC. There is a weird quirk
where the "first" global in each link is never GC-ed because of the
section symbols.
At this moment it does not work on Gold (as in the globals are never
stripped).
This is a second re-land of r298158. This time, this feature is
limited to -fdata-sections builds.
llvm-svn: 301587
When possible, put ASan ctor/dtor in comdat.
The only reason not to is global registration, which can be
TU-specific. This is not the case when there are no instrumented
globals. This is also limited to ELF targets, because MachO does
not have comdat, and COFF linkers may GC comdat constructors.
The benefit of this is a lot less __asan_init() calls: one per DSO
instead of one per TU. It's also necessary for the upcoming
gc-sections-for-globals change on Linux, where multiple references to
section start symbols trigger quadratic behaviour in gold linker.
This is a second re-land of r298756. This time with a flag to disable
the whole thing to avoid a bug in the gold linker:
https://sourceware.org/bugzilla/show_bug.cgi?id=19002
llvm-svn: 301586
Currently, this pass only focuses on *trivial* loop unswitching. At that
reduced problem it remains significantly better than the current loop
unswitch:
- Old pass is worse than cubic complexity. New pass is (I think) linear.
- New pass is much simpler in its design by focusing on full unswitching. (See
below for details on this).
- New pass doesn't carry state for thresholds between pass iterations.
- New pass doesn't carry state for correctness (both miscompile and
infloop) between pass iterations.
- New pass produces substantially better code after unswitching.
- New pass can handle more trivial unswitch cases.
- New pass doesn't recompute the dominator tree for the entire function
and instead incrementally updates it.
I've ported all of the trivial unswitching test cases from the old pass
to the new one to make sure that major functionality isn't lost in the
process. For several of the test cases I've worked to improve the
precision and rigor of the CHECKs, but for many I've just updated them
to handle the new IR produced.
My initial motivation was the fact that the old pass carried state in
very unreliable ways between pass iterations, and these mechansims were
incompatible with the new pass manager. However, I discovered many more
improvements to make along the way.
This pass makes two very significant assumptions that enable most of these
improvements:
1) Focus on *full* unswitching -- that is, completely removing whatever
control flow construct is being unswitched from the loop. In the case
of trivial unswitching, this means removing the trivial (exiting)
edge. In non-trivial unswitching, this means removing the branch or
switch itself. This is in opposition to *partial* unswitching where
some part of the unswitched control flow remains in the loop. Partial
unswitching only really applies to switches and to folded branches.
These are very similar to full unrolling and partial unrolling. The
full form is an effective canonicalization, the partial form needs
a complex cost model, cannot be iterated, isn't canonicalizing, and
should be a separate pass that runs very late (much like unrolling).
2) Leverage LLVM's Loop machinery to the fullest. The original unswitch
dates from a time when a great deal of LLVM's loop infrastructure was
missing, ineffective, and/or unreliable. As a consequence, a lot of
complexity was added which we no longer need.
With these two overarching principles, I think we can build a fast and
effective unswitcher that fits in well in the new PM and in the
canonicalization pipeline. Some of the remaining functionality around
partial unswitching may not be relevant today (not many test cases or
benchmarks I can find) but if they are I'd like to add support for them
as a separate layer that runs very late in the pipeline.
Purely to make reviewing and introducing this code more manageable, I've
split this into first a trivial-unswitch-only pass and in the next patch
I'll add support for full non-trivial unswitching against a *fixed*
threshold, exactly like full unrolling. I even plan to re-use the
unrolling thresholds, as these are incredibly similar cost tradeoffs:
we're cloning a loop body in order to end up with simplified control
flow. We should only do that when the total growth is reasonably small.
One of the biggest changes with this pass compared to the previous one
is that previously, each individual trivial exiting edge from a switch
was unswitched separately as a branch. Now, we unswitch the entire
switch at once, with cases going to the various destinations. This lets
us unswitch multiple exiting edges in a single operation and also avoids
numerous extremely bad behaviors, where we would introduce 1000s of
branches to test for thousands of possible values, all of which would
take the exact same exit path bypassing the loop. Now we will use
a switch with 1000s of cases that can be efficiently lowered into
a jumptable. This avoids relying on somehow forming a switch out of the
branches or getting horrible code if that fails for any reason.
Another significant change is that this pass actively updates the CFG
based on unswitching. For trivial unswitching, this is actually very
easy because of the definition of loop simplified form. Doing this makes
the code coming out of loop unswitch dramatically more friendly. We
still should run loop-simplifycfg (at the least) after this to clean up,
but it will have to do a lot less work.
Finally, this pass makes much fewer attempts to simplify instructions
based on the unswitch. Something like loop-instsimplify, instcombine, or
GVN can be used to do increasingly powerful simplifications based on the
now dominating predicate. The old simplifications are things that
something like loop-instsimplify should get today or a very, very basic
loop-instcombine could get. Keeping that logic separate is a big
simplifying technique.
Most of the code in this pass that isn't in the old one has to do with
achieving specific goals:
- Updating the dominator tree as we go
- Unswitching all cases in a switch in a single step.
I think it is still shorter than just the trivial unswitching code in
the old pass despite having this functionality.
Differential Revision: https://reviews.llvm.org/D32409
llvm-svn: 301576
Just calling dropAllReferences leaves pointers to the ConstantExpr
behind, so we would eventually crash with a null pointer dereference.
Differential Revision: https://reviews.llvm.org/D32551
llvm-svn: 301575
Summary:
Misc improvements to debug output. Fix a couple typos and also dump the
value profile before we make any profitability checks.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32607
llvm-svn: 301574
also a discussion about exactly what we should do prior to re-enabling
it.
The current bug is http://llvm.org/PR32821 and the discussion about this
is in the review thread for r300200.
llvm-svn: 301505
This patch introduces a new KnownBits struct that wraps the two APInt used by computeKnownBits. This allows us to treat them as more of a unit.
Initially I've just altered the signatures of computeKnownBits and InstCombine's simplifyDemandedBits to pass a KnownBits reference instead of two separate APInt references. I'll do similar to the SelectionDAG version of computeKnownBits/simplifyDemandedBits as a separate patch.
I've added a constructor that allows initializing both APInts to the same bit width with a starting value of 0. This reduces the repeated pattern of initializing both APInts. Once place default constructed the APInts so I added a default constructor for those cases.
Going forward I would like to add more methods that will work on the pairs. For example trunc, zext, and sext occur on both APInts together in several places. We should probably add a clear method that can be used to clear both pieces. Maybe a method to check for conflicting information. A method to return (Zero|One) so we don't write it out everywhere. Maybe a method for (Zero|One).isAllOnesValue() to determine if all bits are known. I'm sure there are many other methods we can come up with.
Differential Revision: https://reviews.llvm.org/D32376
llvm-svn: 301432
Commits were:
"Use WeakVH instead of WeakTrackingVH in AliasSetTracker's UnkownInsts"
"Add a new WeakVH value handle; NFC"
"Rename WeakVH to WeakTrackingVH; NFC"
The changes assumed pointers are 8 byte aligned on all architectures.
llvm-svn: 301429
Summary:
I plan to use WeakVH to mean "nulls itself out on deletion, but does
not track RAUW" in a subsequent commit.
Reviewers: dblaikie, davide
Reviewed By: davide
Subscribers: arsenm, mehdi_amini, mcrosier, mzolotukhin, jfb, llvm-commits, nhaehnle
Differential Revision: https://reviews.llvm.org/D32266
llvm-svn: 301424
Summary:
Otherwise we might end up with some empty basic blocks or
single-entry-single-exit basic blocks.
This fixes PR32085
Reviewers: chandlerc, danielcdh
Subscribers: mehdi_amini, RKSimon, llvm-commits
Differential Revision: https://reviews.llvm.org/D30468
llvm-svn: 301395
The code I've removed here exists in ExpandBinOp in InstSimplify which we call into before SimplifyUsingDistributiveLaws. The code in InstSimplify looks to have been copied from here.
I verified this code doesn't fire on any lit tests. Not that that proves its definitely dead.
Differential Revision: https://reviews.llvm.org/D32472
llvm-svn: 301341
This patch uses various APInt methods to reduce temporary APInt creation.
This should be all of the unrelated cleanups that got buried in D32376(creating a KnownBits struct) as well as some pointed out by Simon during the review of that. Plus a few improvements to use counting instead of masking.
I've left out any places where we do something like (KnownZero & KnownOne) != 0 as I plan to add a helper method to KnownBits to ask that question and didn't want to thrash that code an additional time.
Differential Revision: https://reviews.llvm.org/D32495
llvm-svn: 301338
The matching here wasn't able to handle all the possible commutes. It always assumed the not would be on the left of the xor, but that's not guaranteed.
Differential Revision: https://reviews.llvm.org/D32474
llvm-svn: 301316
One of the fast-math optimizations is to replace calls to standard double
functions with their float equivalents, e.g. exp -> expf. However, this can
cause infinite loops for the following:
float expf(float val) { return (float) exp((double) val); }
A similar inline declaration exists in the MinGW-w64 math.h header file which
when compiled with -O2/3 and fast-math generates infinite loops.
So this fix checks that the calling function to the standard double function
that is being replaced does not match the float equivalent.
Differential Revision: https://reviews.llvm.org/D31806
llvm-svn: 301304
This patch is part of D28975's breakdown.
Genreating the control-flow to guard predicated instructions modified to
only use SplitBlockAndInsertIfThen() for producing the if-then construct.
Differential Revision: https://reviews.llvm.org/D32224
llvm-svn: 301293
We need to do this to prevent a miscompile which sinks an objc_retain
past an objc_release that releases the object objc_retain retains. This
happens because the top-down and bottom-up traversals each determines
the insert point for retain or release individually without knowing
where the other instruction is moved.
For example, when the following IR is fed to the ARC optimizer, the
top-down traversal decides to insert objc_retain right before
objc_release and the bottom-up traversal decides to insert objc_release
right after clang.arc.use.
(IR before ARC optimizer)
%11 = call i8* @objc_retain(i8* %10)
call void (...) @clang.arc.use(%0* %5)
call void @llvm.dbg.value(...)
call void @objc_release(i8* %6)
This reverses the order of objc_release and objc_retain, which causes
the object to be destructed prematurely.
(IR after ARC optimizer)
call void (...) @clang.arc.use(%0* %5)
call void @objc_release(i8* %6)
call void @llvm.dbg.value(...)
%11 = call i8* @objc_retain(i8* %10)
rdar://problem/30530580
llvm-svn: 301289
We can simplify (and (icmp X, C1), (icmp X, C2)) to one of the icmps in many cases.
I had to check some of these with Alive to prove to myself it's right, but everything
seems to check out. Eg, the code in instcombine was completely ignoring predicates with
mismatched signedness.
Handling or-of-icmps would be a follow-up step.
Differential Revision: https://reviews.llvm.org/D32143
llvm-svn: 301260
Summary:
Ensure that the new merge BB (which contains the rest of the original BB
after the mem op being optimized) gets a profile frequency, in case
there are additional mem ops later in the BB. Otherwise they get skipped
as the merge BB looks cold.
Reviewers: davidxl, xur
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32447
llvm-svn: 301244
This reverts commit r300732. This breaks a few tests.
I think the problem is related to adding more uses of
the condition that don't yet exist at this point.
llvm-svn: 301242
The current Loop Unroll implementation works with loops having a
single latch that contains a conditional branch to a block outside
the loop (the other successor is, by defition of latch, the header).
If this precondition doesn't hold, avoid unrolling the loop as
the code is not ready to handle such circumstances.
Differential Revision: https://reviews.llvm.org/D32261
llvm-svn: 301239
This is a straight cut and paste, but there's a bigger problem: if this
fold exists for simplifyOr, there should be a DeMorganized version for
simplifyAnd. But more than that, we have a patchwork of ad hoc logic
optimizations in InstCombine. There should be some structure to ensure
that we're not missing sibling folds across and/or/xor.
llvm-svn: 301213
When the location description of a source variable involves arithmetic
on the value itself, it needs to be marked with DW_OP_stack_value since it
is not describing the variable's location, but rather its value.
This is a follow-up to r297971 and fixes the source testcase quoted in
the comment in debuginfo-dce.ll.
rdar://problem/30725338
This reapplies r301093 without modifications.
llvm-svn: 301210
There is logic to track the expected number of instructions
produced. It thought in this case an instruction would
be necessary to negate the result, but here it folded
into a ConstantExpr fneg when the non-undef value operand
was cancelled out by the second fsub.
I'm not sure why we don't fold constant FP ops with undef currently,
but I think that would also avoid this problem.
llvm-svn: 301199
Summary:
Instead of keeping a variable indicating whether there are early exits
in the loop. We keep all the early exits. This improves LICM's ability to
move instructions out of the loop based on is-guaranteed-to-execute.
I am going to update compilation time as well soon.
Reviewers: hfinkel, sanjoy, efriedma, mkuper
Reviewed By: hfinkel
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D32433
llvm-svn: 301196
Summary:
The return value of these intrinsics should always have 0 bits for
inactive threads. This means that when all arguments are constant
and the comparison evaluates to true, the intrinsic should return
the current exec mask.
Fixes some GL_ARB_shader_ballot tests.
Reviewers: arsenm
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D32344
llvm-svn: 301195
We handled all of the commuted variants for plain xor already,
although they were scattered around and sometimes folded less
efficiently using distributive laws. We had no folds for not-xor.
Handling all of these patterns consistently is part of trying to
reinstate:
https://reviews.llvm.org/rL300977
llvm-svn: 301144
Summary:
In case all predecessor go to a single successor of current BB. We want to fold (not thread).
I failed to update the phi nodes properly in the last patch https://reviews.llvm.org/rL300657.
Phi nodes values are per predecessor in LLVM.
Reviewers: sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32400
llvm-svn: 301139
There's probably some better way to write this that eliminates the
code duplication without hurting readability, but at least this
eliminates the logic holes and is hopefully slightly more efficient
than creating new instructions.
llvm-svn: 301129
This reverts commit r301105, 4, 3 and 1, as a follow up of the previous
revert, which broke even more bots.
For reference:
Revert "[APInt] Use operator<<= where possible. NFC"
Revert "[APInt] Use operator<<= instead of shl where possible. NFC"
Revert "[APInt] Use ashInPlace where possible."
PR32754.
llvm-svn: 301111
... in the per-TU -O0 pipeline.
The problem is that there could be passes registered using
`addExtensionsToPM()` introducing unnamed globals.
Asan is an example, but there may be others. Building cppcheck
with `-flto=thin` and `-fsanitize=address` triggers an assertion
while we're reading bitcode (in lib/LTO), as the BitcodeReader
assumes there are no unnamed globals (because the namer has run).
Unfortunately I wasn't able to find an easy way to test this.
I added a comment in the hope nobody moves this again.
llvm-svn: 301102
When the location description of a source variable involves arithmetic
on the value itself, it needs to be marked with DW_OP_stack_value since it
is not describing the variable's location, but rather its value.
This is a follow-up to r297971 and fixes the source testcase quoted in
the comment in debuginfo-dce.ll.
rdar://problem/30725338
llvm-svn: 301093
The later uses of dyn_castNotVal in this block are either
incomplete (doesn't handle vector constants) or overstepping
(shouldn't handle constants at all), but this first use is
just unnecessary. 'I' is obviously not a constant, and it
can't be a not-of-a-not because that would already be
instsimplified.
llvm-svn: 301088
The bug was introduced by r301018 "[InstCombine] fadd double (sitofp x), y check that the promotion is valid". The patch didn't expect that fadd can be on vectors not necessarily scalars. Add vector support along with the test.
llvm-svn: 301070
Fixes leaving intermediate flat addressing computations
where a GEP instruction's source is a constant expression.
Still leaves behind a trivial addrspacecast + gep pair that
instcombine is able to handle, which ideally could be folded
here directly.
llvm-svn: 301044
Doing these transformations check that the result of integer addition is representable in the FP type.
(fadd double (sitofp x), fpcst) --> (sitofp (add int x, intcst))
(fadd double (sitofp x), (sitofp y)) --> (sitofp (add int x, y))
This is a fix for https://bugs.llvm.org//show_bug.cgi?id=27036
Reviewed By: andrew.w.kaylor, scanon, spatel
Differential Revision: https://reviews.llvm.org/D31182
llvm-svn: 301018
Currently we choose PostBB as the single successor of QFB, but its possible that QTB's single successor is QFB which would make QFB the correct choice.
Differential Revision: https://reviews.llvm.org/D32323
llvm-svn: 300992
places based on it.
Existing constant hoisting pass will merge a group of contants in a small range
and hoist the const materialization code to the common dominator of their uses.
However, if the uses are all in cold pathes, existing implementation may hoist
the materialization code from cold pathes to a hot place. This may hurt performance.
The patch introduces BFI to the pass and selects the best insertion places based
on it.
The change is controlled by an option consthoist-with-block-frequency which is
off by default for now.
Differential Revision: https://reviews.llvm.org/D28962
llvm-svn: 300989
Phi nodes in non-header blocks are converted to select instructions after
if-conversion. This patch updates the cost model to account for the selects.
Differential Revision: https://reviews.llvm.org/D31906
llvm-svn: 300980
CodeExtractor looks up the dominator node corresponding to return blocks
when splitting them. If one of these blocks is unreachable, there's no
node in the Dom and CodeExtractor crashes because it doesn't check
for domtree node validity.
In theory, we could add just a check for skipping null DTNodes in
`splitReturnBlock` but the fix I propose here is slightly different. To the
best of my knowledge, unreachable blocks are irrelevant for the algorithm,
therefore we can just skip them when building the candidate set in the
constructor.
Differential Revision: https://reviews.llvm.org/D32335
llvm-svn: 300946
The demanded mask and the constant should always be the same width for all callers today.
Also stop copying the demanded mask as its passed in. We should avoid allocating memory unless we are going to do something. The final AND to create the new constant will take care of it.
llvm-svn: 300927
getSignBit is a static function that creates an APInt with only the sign bit set. getSignMask seems like a better name to convey its functionality. In fact several places use it and then store in an APInt named SignMask.
Differential Revision: https://reviews.llvm.org/D32108
llvm-svn: 300856
This question comes up in many places in SimplifyDemandedBits. This makes it easy to ask without allocating additional temporary APInts.
The BitVector class provides a similar functionality through its (IMHO badly named) test(const BitVector&) method. Though its output polarity is reversed.
I've provided one example use case in this patch. I plan to do more as a follow up.
Differential Revision: https://reviews.llvm.org/D32258
llvm-svn: 300851
Currently we don't explicitly process ConstantDataSequential, ConstantAggregateZero, or ConstantVector, or Undef before applying the Depth limit. Instead they occur after the depth check in the non-instruction path.
For the constant types that we do handle, the code is replicated from computeKnownBits.
This patch fixes the missing constant handling and the reduces the amount of code by just using computeKnownBits directly for any type of Constant.
Differential Revision: https://reviews.llvm.org/D32123
llvm-svn: 300849
This change is correct because the verifier requires that at most one
argument be marked 'sret'.
NFC, removes a use of AttributeList slot APIs.
llvm-svn: 300784
This is preparation for a clang change to improve the [[nodiscard]] warning to not be ignored on methods that return a class marked [[nodiscard]] that are defined in the class itself. See D32207.
We should consider adding wrapper methods to APInt that return the overflow flag directly and discard the APInt result. This would eliminate the void casts and the need to create a bool before the call to pass to the out param.
llvm-svn: 300758
The most common case for a branch condition is
a single use compare. Directly invert the branch
predicate rather than adding a lot of xor i1 true
which the DAG will have to fold later.
This produces nicer to read structurizer output.
This produces some random changes in codegen
due to the DAG swapping branch conditions itself,
and then does a poor job of dealing with those
inverts.
llvm-svn: 300732
Summary:
See http://llvm.org/docs/LangRef.html#non-integral-pointer-type
The NewGVN test does not fail without these changes (perhaps it does
try to coerce pointers <-> integers to begin with?), but I added the
test case anyway.
Reviewers: dberlin
Subscribers: mcrosier, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D32208
llvm-svn: 300730
This should simplify the call sites, which typically want to tweak one
attribute at a time. It should also avoid creating ephemeral
AttributeLists that live forever.
llvm-svn: 300718
Summary: In case all predecessor go to a single successor of current BB. We want to fold (not thread).
Reviewers: efriedma, sanjoy
Reviewed By: sanjoy
Subscribers: dberlin, majnemer, llvm-commits
Differential Revision: https://reviews.llvm.org/D30869
llvm-svn: 300657
In tryToVectorizeList, under a very limited circumstance (when entered
from tryToVectorizePair), the values may be reordered (swapped) and the
SLP tree is built with the new order. This extends that to the case when
starting from phis in vectorizeChainsInBlock when there are exactly two
phis. The textual order of phi nodes shouldn't really matter. Without
this change, the loop body in the accompnaying test case is fully vectorized
when we swap the orde of the phis but not with this order. While this
doesn't solve the phi-ordering problem in a general way (for more than 2
phis), this is simple fix that piggybacks on an existing mechanism and
is useful in cases like multiplying two complex numbers.
Differential revision: https://reviews.llvm.org/D32065
llvm-svn: 300574
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.
This adds an lshrInPlace(const APInt &) version as well.
Differential Revision: https://reviews.llvm.org/D32155
llvm-svn: 300566
This patch is part of D28975's breakdown.
Add caching for block masks similar to the cache already used for edge masks,
replacing generation per user with reusing the first generated value which
dominates all uses.
Differential Revision: https://reviews.llvm.org/D32054
llvm-svn: 300557
Before this patch, we always called method 'findCalleeFunctionSamples()' on
intrinsic calls. However, intrinsic calls like llvm.dbg.value() are not viable
candidates for obvious reasons.
No functional change intended.
Differential Revision: https://reviews.llvm.org/D32008
llvm-svn: 300541
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
- describe a variable in a register
- consist of only a DW_OP_reg
2. Memory location descriptions
- describe the address of a variable
3. Implicit location descriptions
- describe the value of a variable
- end with DW_OP_stack_value & friends
The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident. This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.
This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.
There are two major changes in this patch:
I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8
DBG_VALUE, RAX --> DW_OP_reg0 +0
DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0
All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.
https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>
Differential Revision: https://reviews.llvm.org/D31439
llvm-svn: 300522
Summary: If there is suffix added in the function name (e.g. module hash added by thinLTO), we will not be able to find a match in profile as the suffix does not exist in profile. This patch build a map from function name to Function *. The map includes the entry for the stripped function name so that inlineHotFunctions can find the corresponding function to promote/inline.
Reviewers: davidxl, dnovillo, tejohnson
Reviewed By: davidxl
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D31952
llvm-svn: 300507
The use list is a linked list so getNumUses requires a linear scan through the whole list. hasNUses will stop scanning at N and see if that is the end.
llvm-svn: 300505
So, `cast<Instruction>` is not guaranteed to succeed. Change the
code so that we create a new constant and use it in the newly
created instruction, as it's done in other places in InstCombine.
OK'ed by Sanjay/Craig. Fixes PR32686.
llvm-svn: 300495
Add a top-level STRTAB block containing a string table blob, and start storing
strings for module codes FUNCTION, GLOBALVAR, ALIAS, IFUNC and COMDAT in
the string table.
This change allows us to share names between globals and comdats as well
as between modules, and improves the efficiency of loading bitcode files by
no longer using a bit encoding for symbol names. Once we start writing the
irsymtab to the bitcode file we will also be able to share strings between
it and the module.
On my machine, link time for Chromium for Linux with ThinLTO decreases by
about 7% for no-op incremental builds or about 1% for full builds. Total
bitcode file size decreases by about 3%.
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2017-April/111732.html
Differential Revision: https://reviews.llvm.org/D31838
llvm-svn: 300464
Causes some VGPR usage improvements in shaderdb, but
introduces some SGPR spilling regressions due to random
scheduling changes later.
llvm-svn: 300453
This patch is a generalization of the improvement introduced in rL296898.
Previously, we were able to peel one iteration of a loop to get rid of a Phi that becomes
an invariant on the 2nd iteration. In more general case, if a Phi becomes invariant after
N iterations, we can peel N times and turn it into invariant.
In order to do this, we for every Phi in loop's header we define the Invariant Depth value
which is calculated as follows:
Given %x = phi <Inputs from above the loop>, ..., [%y, %back.edge].
If %y is a loop invariant, then Depth(%x) = 1.
If %y is a Phi from the loop header, Depth(%x) = Depth(%y) + 1.
Otherwise, Depth(%x) is infinite.
Notice that if we peel a loop, all Phis with Depth = 1 become invariants,
and all other Phis with finite depth decrease the depth by 1.
Thus, peeling N first iterations allows us to turn all Phis with Depth <= N
into invariants.
Reviewers: reames, apilipenko, mkuper, skatkov, anna, sanjoy
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31613
llvm-svn: 300446
When peeling loops basing on phis becoming invariants, we make a wrong loop size check.
UP.Threshold should be compared against the total numbers of instructions after the transformation,
which is equal to 2 * LoopSize in case of peeling one iteration.
We should also check that the maximum allowed number of peeled iterations is not zero.
Reviewers: sanjoy, anna, reames, mkuper
Reviewed By: mkuper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31753
llvm-svn: 300441
If we already called computeKnownBits for the RHS being a constant power of 2, we've already computed everything we can and should just stop. I think previously we would still recurse if we had determined the result was negative or had not determined the sign bit at all.
llvm-svn: 300432
This patch adds new optimization (Folding cmp(sub(a,b),0) into cmp(a,b))
to instCombineCall pass and was written specific for X86 CMP intrinsics.
Differential Revision: https://reviews.llvm.org/D31398
llvm-svn: 300422
This is a version of D32090 that unifies all of the
`getInstrProf*SectionName` helper functions. (Note: the build failures
which D32090 would have addressed were fixed with r300352.)
We should unify these helper functions because they are hard to use in
their current form. E.g we recently introduced more helpers to fix
section naming for COFF files. This scheme doesn't totally succeed at
hiding low-level details about section naming, so we should switch to an
API that is easier to maintain.
This is not an NFC commit because it fixes llvm-cov's testing support
for COFF files (this falls out of the API change naturally). This is an
area where we lack tests -- I will see about adding one as a follow up.
Testing: check-clang, check-profile, check-llvm.
Differential Revision: https://reviews.llvm.org/D32097
llvm-svn: 300381
When checking if we should return a constant, we create some temporary APInts to see if we know all bits. But the exact computations we do are needed in several other locations in the same code.
This patch moves them to named temporaries so we can reuse them.
Ideally we'd write directly to KnownZero/One, but we currently seem to only write those variables after all the simplifications checks and I didn't want to change that with this patch.
Differential Revision: https://reviews.llvm.org/D32094
llvm-svn: 300376
This avoids the confusing 'CS.paramHasAttr(ArgNo + 1, Foo)' pattern.
Previously we were testing return value attributes with index 0, so I
introduced hasReturnAttr() for that use case.
llvm-svn: 300367
...when C1 differs from C2 by one bit and C1 <u C2:
http://rise4fun.com/Alive/Vuo
And move related folds to a helper function. This reduces code duplication and
will make it easier to remove the scalar-only restriction as a follow-up step.
llvm-svn: 300364
Vedant Kumar