If the liveness of a physical register was invalid, this
was attempting to iterate the subregisters of all register
uses of the instruction, which would assert when it
encountered an implicit virtual register operand.
llvm-svn: 340763
I noticed this along with the patterns in D51125, but when the index is variable,
we don't convert insertelement into a build_vector.
For x86, that means these get expanded at legalization time into the loading/spilling
code that we see in the tests. I think it's always better to avoid going to memory on
these, and we get the optimal 'broadcast' if it's available.
I suspect other targets may want to look at enabling the hook. AArch64 and AMDGPU have
regression tests that would be affected (although I did not check what would happen in
those cases). In the most basic cases shown here, AArch64 would probably do much
better with a splat.
Differential Revision: https://reviews.llvm.org/D51186
llvm-svn: 340705
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.
All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.
llvm-svn: 340701
The core get and set routines move to the `Instruction` class. These
routines are only valid to call on instructions which are terminators.
The iterator and *generic* range based access move to `CFG.h` where all
the other generic successor and predecessor access lives. While moving
the iterator here, simplify it using the iterator utilities LLVM
provides and updates coding style as much as reasonable. The APIs remain
pointer-heavy when they could better use references, and retain the odd
behavior of `operator*` and `operator->` that is common in LLVM
iterators. Adjusting this API, if desired, should be a follow-up step.
Non-generic range iteration is added for the two instructions where
there is an especially easy mechanism and where there was code
attempting to use the range accessor from a specific subclass:
`indirectbr` and `br`. In both cases, the successors are contiguous
operands and can be easily iterated via the operand list.
This is the first major patch in removing the `TerminatorInst` type from
the IR's instruction type hierarchy. This change was discussed in an RFC
here and was pretty clearly positive:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123407.html
There will be a series of much more mechanical changes following this
one to complete this move.
Differential Revision: https://reviews.llvm.org/D47467
llvm-svn: 340698
Summary:
Previously the value being stored is the last operand in SDNode. This causes the type legalizer to visit the mask operand before the value operand. The type legalizer was more complicated because of this since we want the type of the value to drive the decisions.
This patch moves the value to be the first operand so we visit it first during type legalization. It also simplifies the type legalization code accordingly.
X86 is currently the only in tree target that uses this SDNode. Not sure if there are any users out of tree.
Reviewers: RKSimon, delena, hfinkel, eli.friedman
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D50402
llvm-svn: 340689
Summary:
If any of the bundled instructions are marked as FrameSetup
or FrameDestroy, then that property is set on the BUNDLE
instruction as well.
As long as the scheduler/packetizer aren't mixing
prologue/epilogue instructions (i.e. all the bundled
instructions have the same property) then this simply gives
the bundle the correct property (so when using a bundle
iterator in late passes a bundle will be correctly identified
as FrameSetup/FrameDestroy).
When for example bundling a mix of FrameSetup instructions
with non-FrameSetup instructions it could be discussed if
the bundle should have the property or not. The choice here
has been to set these properties on the BUNDLE instruction if
any of the bundled instructions have the property set.
Reviewers: #debug-info, kparzysz
Reviewed By: kparzysz
Subscribers: vsk, thegameg, llvm-commits
Differential Revision: https://reviews.llvm.org/D50637
llvm-svn: 340680
Summary:
When computeIntervals is looking through COPY instruction to
extend the location mapping for a debug variable it did not
handle subregisters correctly.
For example
DBG_VALUE debug-use %0.sub_8bit_hi, ...
%1:gr16 = COPY %0
was transformed into
DBG_VALUE debug-use %0.sub_8bit_hi, ...
%1:gr16 = COPY %0
DBG_VALUE debug-use %1, ...
So the subregister index was missing in the added DBG_VALUE.
As long as the subreg refered to the least significant bits
of the superreg, then I guess we could get the correct
result in a debugger even when referring to the superreg.
But as in the example above when the subreg refers to other
parts of the superreg, then debuginfo would be incorrect.
I'm not sure exactly how to fix this properly, so this patch
just avoids looking through the COPY when there is a subreg
involved (for more info, see the FIXME added in the code).
Reviewers: rnk, aprantl
Reviewed By: aprantl
Subscribers: JDevlieghere, llvm-commits
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D50788
llvm-svn: 340679
Otherwise, the debug info is incorrect. On its own, this is mostly
harmless, but the safe-stack also later inlines the call to
__safestack_pointer_address, which leads to debug info with the wrong
scope, which eventually causes an assertion failure (and incorrect debug
info in release mode).
Differential Revision: https://reviews.llvm.org/D51075
llvm-svn: 340651
Firstly, require the symbol to be used within the module. If a
symbol is unused within a module, then by definition it cannot be
address-significant within that module. This condition is useful on all
platforms because it could make symbol tables smaller -- without this
change, emitting an address-significance table could cause otherwise
unused undefined symbols to be added to the object file.
But this change is necessary with COFF specifically in order to
preserve the property that an unreferenced undefined symbol in an IR
module does not result in a link failure. This is already the case for
ELF because ELF linkers only reject links with unresolved symbols if
there is a relocation to that symbol, but COFF linkers require all
undefined symbols to be resolved regardless of relocations. So if
a module contains an unreferenced undefined symbol, we need to make
sure not to add it to the address-significance table (and thus the
symbol table) in case it doesn't end up resolved at link time.
Secondly, do not add dllimport symbols to the table. These symbols
won't be able to be resolved because their definitions live in another
module and are accessed via the IAT, and the address-significance
table has no effect on other modules anyway. It wouldn't make sense
to add the IAT entry symbol to the address-significance table either
because the IAT entry isn't address-significant -- the generated code
never takes its address.
Differential Revision: https://reviews.llvm.org/D51199
llvm-svn: 340648
My previoust test case had skipped CUs from one TU out of a two-TU LTO
scenario, which meant the CU index wasn't needed (as it was unambiguous
which CU a table entry applied to) - expanding the test to use 3 TUs,
skipping one (so long as it's not the last one) shows the indexes are
miscomputed. Fix that with a little indirection for the index.
llvm-svn: 340646
Previously we allowed the store to be Custom. But without knowing for sure that the Custom handling won't split the store, we shouldn't convert a volatile store. We also probably shouldn't be creating a store the requires custom handling after LegalizeOps. This could lead to an infinite loop if the custom handling was to insert a bitcast. Though I guess isStoreBitCastBeneficial could be used to block such a loop.
The test changes here are due to the volatile part of this. The stores in the test are all volatile and i32 stores are marked custom, So we are no longer converting them
This is related to D50491 where I was trying to allow some bitcasting of volatile loads
Differential Revision: https://reviews.llvm.org/D50578
llvm-svn: 340626
Having the KnownBits as an output parameter is kind of awkward to use
and a holdover from when it was two separate APInts. Instead, just
return a KnownBits object.
I'm leaving the existing interface in place for now, since updating
the callers all at once would be thousands of lines of diff.
llvm-svn: 340594
Summary:
I got "Use not jointly dominated by defs" when removePartialRedundancy
attempted to prune then re-extend a subrange whose only liveness was a
dead def at the copy being removed.
V2: Removed junk from test. Improved comment.
V3: Addressed minor review comments.
Subscribers: MatzeB, qcolombet, nhaehnle, llvm-commits
Differential Revision: https://reviews.llvm.org/D50914
Change-Id: I6f894e9f517f71e921e0c6d81d28c5f344db8dad
llvm-svn: 340549
This patch's test case relies on debug prints which isn't generally an
OK way to test stuff in LLVM and fails whenever asserts aren't enabled.
I've send a heads-up to the commit and detailed comments on the review.
llvm-svn: 340513
In lib/CodeGen/LiveDebugVariables.cpp, it uses std::prev(MBBI) to
get DebugValue's SlotIndex. However, the previous instruction may be
also a debug instruction. It could not use a debug instruction to query
SlotIndex in mi2iMap.
Scan all debug instructions and use the first debug instruction to query
SlotIndex for following debug instructions. Only handle DBG_VALUE in
handleDebugValue().
Differential Revision: https://reviews.llvm.org/D50621
llvm-svn: 340508
This solves the motivating case from:
https://bugs.llvm.org/show_bug.cgi?id=38527
If we are legalizing an FP vector op that maps to 1 of the LLVM intrinsics that mimic libm calls,
but we're going to end up with scalar libcalls for that vector type anyway, then we should unroll
the vector op into scalars before widening. This avoids libcalls because we've lost the knowledge
that some of the scalar elements are undef.
Differential Revision: https://reviews.llvm.org/D50791
llvm-svn: 340469
The inline sequence is very long (about 70 bytes on Thumb1), so it's
not really a good idea to inline it, especially when optimizing for
size.
Differential Revision: https://reviews.llvm.org/D47917
llvm-svn: 340458
Instead of asserting that the function doesn't have any unreachable
code, just ignore it for the purpose of computing liveness.
Differential Revision: https://reviews.llvm.org/D51070
llvm-svn: 340456
CodeGenPrepare has a strategy for moving dbg.values so that a value's
definition always dominates its debug users. This cleanup was happening
too early (before certain CGP transforms were run), resulting in some
dbg.value use-before-def errors.
Perform this cleanup as late as possible to avoid use-before-def.
llvm-svn: 340370
In optimizeSelectInst, when scanning for candidate selects to rewrite
into branches, scan past debug intrinsics. This makes the debug-enabled
and non-debug paths through optimizeSelectInst more congruent.
NFC because every select is eventually visited either way.
llvm-svn: 340368
Summary:
Computing the remaining latency can be very expensive especially
on graphs of N nodes where the number of edges approaches N^2.
This reduces the compile time of a pathological case with the
AMDGPU backend from ~7.5 seconds to ~3 seconds. This test case has
a basic block with 2655 stores, each with somewhere between 500
and 1500 successors and predecessors.
Reviewers: atrick, MatzeB, airlied, mareko
Reviewed By: mareko
Subscribers: tpr, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D50486
llvm-svn: 340346
Summary:
Catchpads and cleanuppads are not funclet entries; they are only EH
scope entries. We already dont't set `isEHFuncletEntry` for catchpads.
This patch does the same thing for cleanuppads.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50654
llvm-svn: 340330
Summary:
When RegisterCoalescer::reMaterializeTrivialDef is substituting
a register use in a DBG_VALUE instruction, and the old register
is a subreg, and the new register is a physical register,
then we need to use substPhysReg in order to extract the correct
subreg.
Reviewers: wmi, aprantl
Reviewed By: wmi
Subscribers: hiraditya, MatzeB, qcolombet, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D50844
llvm-svn: 340326
Summary:
So far, `isReturn` property is used to mean both a return instruction
from a functon and the end of an EH scope, a scope that starts with a EH
scope entry BB and ends with a catchret or a cleanupret instruction.
Because WinEH uses funclets, all EH-scope-ending instructions are also
real return instruction from a function. But for wasm, they only serve
as the end marker of an EH scope but not a return instruction that
exits a function. This mismatch caused incorrect prolog and epilog
generation in wasm EH scopes. This patch fixes this.
This patch is in the same vein with rL333045, which splits
`MachineBasicBlock::isEHFuncletEntry` into `isEHFuncletEntry` and
`isEHScopeEntry`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D50653
llvm-svn: 340325
In removeCopyByCommutingDef, segments from the source live range are
copied into (and merged with) the segments of the target live range.
This is performed for all subranges of the source interval. It can
happen that there will be subranges of the target interval that had
no corresponding subranges in the source interval, and in such cases
these subrages will not be updated. Since the copy being coalesced
is about to be removed, these ranges need to be updated by removing
the segments that are started by the copy.
llvm-svn: 340318
This reverts commit d1341152d91398e9a882ba2ee924147ea2f9b589.
This patch originally made use of Nested MachineIRBuilder buildInstr
calls, and since order of argument processing is not well defined, the
instructions were built slightly in a different order (still correct).
I've removed the nested buildInstr calls to have a defined order now.
Patch was tested by Mikael.
llvm-svn: 340309
Summary:
Previously a BUNDLE instruction inherited the DebugLoc from the
first instruction in the bundle, even if that DebugLoc had no
DILocation. With this commit this is changed into selecting the
first DebugLoc that has a DILocation, by searching among the
bundled instructions.
The idea is to reduce amount of bundles that are lacking
debug locations.
Reviewers: #debug-info, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: JDevlieghere, mattd, llvm-commits
Differential Revision: https://reviews.llvm.org/D50639
llvm-svn: 340267
During combining, ReduceLoadWdith is used to combine AND nodes that
mask loads into narrow loads. This patch allows the mask to be a
shifted constant. This results in a narrow load which is then left
shifted to compensate for the new offset.
Differential Revision: https://reviews.llvm.org/D50432
llvm-svn: 340261
This reduces most of the sdiv stages (the MULHS, shifts etc.) to just zero/identity values and use the numerator scale factor to multiply by +1/-1.
llvm-svn: 340260
Summary:
RegisterCoalescer::reMaterializeTrivialDef used to assert that
the input register was live in. But as shown by the new
coalesce-dead-lanes.mir test case that seems to be a valid
scenario. We now return false instead of the assert, simply
avoiding to remat the dead def.
Normally a COPY of an undef value is eliminated by
eliminateUndefCopy(). Although we only do that when the
destination isn't a physical register. So the situation
above should be limited to the case when we copy an undef
value to a physical register.
Reviewers: kparzysz, wmi, tpr
Reviewed By: kparzysz
Subscribers: MatzeB, qcolombet, tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D50842
llvm-svn: 340255
1. Change the software pipeliner to use unknown size instead of dropping
memory operands. It used to do it before, but MachineInstr::mayAlias
did not handle it correctly.
2. Recognize UnknownSize in MachineInstr::mayAlias.
3. Print and parse UnknownSize in MIR.
Differential Revision: https://reviews.llvm.org/D50339
llvm-svn: 340208
getTargetCustom() requires values for "Kind" in the constructor
that are not in the PSVKind enum. Passing a value that is not inside
an enum as an argument to a constructor of the type of the enum is
UB. Changing to the underlying type of the enum would solve the UB
Differential Revision: https://reviews.llvm.org/D50909
llvm-svn: 340200
This reverts commit 7debc334e6421bb5251ef8f18e97166dfc7dd787.
I missed updating legalizer-info-validation.mir as I had assertions
turned off in my build and that specific test requires asserts. Fixed it
now.
llvm-svn: 340197
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.
Handle the case where the sign bit extends to only part of the small elements.
llvm-svn: 340169
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.
The next step would be to support cases where the large elements aren't all sign bits, and determine the small element equivalent based on the demanded elements.
llvm-svn: 340143
Summary:
I believe this restores the behavior we had before r339147.
Fixes PR38622.
Reviewers: RKSimon, chandlerc, spatel
Reviewed By: chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D50936
llvm-svn: 340120
There are two forms for label debug information in DWARF format.
1. Labels in a non-inlined function:
DW_TAG_label
DW_AT_name
DW_AT_decl_file
DW_AT_decl_line
DW_AT_low_pc
2. Labels in an inlined function:
DW_TAG_label
DW_AT_abstract_origin
DW_AT_low_pc
We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.
The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.
We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.
It also generates label debug information under global isel.
Differential Revision: https://reviews.llvm.org/D45556
llvm-svn: 340039
This patch performs a widening transformation of bitwise atomicrmw
{or,xor,and} and applies it prior to tryExpandAtomicRMW. This operates
similarly to convertCmpXchgToIntegerType. For these operations, the i8/i16
atomicrmw can be implemented in terms of the 32-bit atomicrmw by appropriately
manipulating the operands. There is no functional change for the handling of
partword or/xor, but the transformation for partword 'and' is new.
The advantage of performing this transformation early is that the same
code-path can be used regardless of the approach used to expand the atomicrmw
(AtomicExpansionKind). i.e. the same logic is used for
AtomicExpansionKind::CmpXchg and can also be used by the intrinsic-based
expansion in D47882.
Differential Revision: https://reviews.llvm.org/D48129
llvm-svn: 340027
Add support for cases where only some c1+c2 results exceed the max bitshift, clamping accordingly.
Differential Revision: https://reviews.llvm.org/D35722
llvm-svn: 340010
https://reviews.llvm.org/D50401
Add opcodes for llvm.intrinsic.trunc, round, and update the IRTranslator
for the same.
Reviewed by: dsanders.
llvm-svn: 339977
well as MIR parsing support for `MCSymbol` `MachineOperand`s.
The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.
The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.
The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.
The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.
However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.
Differential Revision: https://reviews.llvm.org/D50833
llvm-svn: 339962
When nodes are reassociated the vector-reduction flag gets lost.
The test case is here is what would happen if you had a sum of absolute differences loop that started with a non-zero but contant sum and that loop was unrolled. The vectorizer will generate a constant vector for the initial value. And DAGCombiner reassociate tries to move it down the addition tree erasing the vector-reduction flag. Interestingly this moves constants the opposite direction of the reassociate IR pass.
I've chosen to just punt on the reassociate, but I suppose we could maybe preserve the flag if both nodes have it set.
Differential Revision: https://reviews.llvm.org/D50827
llvm-svn: 339946
a generically extensible collection of extra info attached to
a `MachineInstr`.
The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.
Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.
I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).
Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.
This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.
The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.
Differential Revision: https://reviews.llvm.org/D50701
llvm-svn: 339940
In cases where the debugger load time is a worthwhile tradeoff (or less
costly - such as loading from a DWP instead of a variety of DWOs
(possibly over a high-latency/distributed filesystem)) against object
file size, it can be reasonable to disable pubnames and corresponding
gdb-index creation in the linker.
A backend-flag version of this was implemented for NVPTX in
D44385/r327994 - which was fine for NVPTX which wouldn't mix-and-match
CUs. Now that it's going to be a user-facing option (likely powered by
"-gno-pubnames", the same as GCC) it should be encoded in the
DICompileUnit so it can vary per-CU.
After this, likely the NVPTX support should be migrated to the metadata
& the previous flag implementation should be removed.
Reviewers: aprantl
Differential Revision: https://reviews.llvm.org/D50213
llvm-svn: 339939
Each use of a value should be jointly dominated by the union of defs and
undefs. It can happen that it will only be jointly dominated by undefs,
and that is still legal. Make sure that the verifier is aware of that.
llvm-svn: 339924
There is no way in the universe, that doing a full-width division in
software will be faster than doing overflowing multiplication in
software in the first place, especially given that this same full-width
multiplication needs to be done anyway.
This patch replaces the previous implementation with a direct lowering
into an overflowing multiplication algorithm based on half-width
operations.
Correctness of the algorithm was verified by exhaustively checking the
output of this algorithm for overflowing multiplication of 16 bit
integers against an obviously correct widening multiplication. Baring
any oversights introduced by porting the algorithm to DAG, confidence in
correctness of this algorithm is extremely high.
Following table shows the change in both t = runtime and s = space. The
change is expressed as a multiplier of original, so anything under 1 is
“better” and anything above 1 is worse.
+-------+-----------+-----------+-------------+-------------+
| Arch | u64*u64 t | u64*u64 s | u128*u128 t | u128*u128 s |
+-------+-----------+-----------+-------------+-------------+
| X64 | - | - | ~0.5 | ~0.64 |
| i686 | ~0.5 | ~0.6666 | ~0.05 | ~0.9 |
| armv7 | - | ~0.75 | - | ~1.4 |
+-------+-----------+-----------+-------------+-------------+
Performance numbers have been collected by running overflowing
multiplication in a loop under `perf` on two x86_64 (one Intel Haswell,
other AMD Ryzen) based machines. Size numbers have been collected by
looking at the size of function containing an overflowing multiply in
a loop.
All in all, it can be seen that both performance and size has improved
except in the case of armv7 where code size has regressed for 128-bit
multiply. u128*u128 overflowing multiply on 32-bit platforms seem to
benefit from this change a lot, taking only 5% of the time compared to
original algorithm to calculate the same thing.
The final benefit of this change is that LLVM is now capable of lowering
the overflowing unsigned multiply for integers of any bit-width as long
as the target is capable of lowering regular multiplication for the same
bit-width. Previously, 128-bit overflowing multiply was the widest
possible.
Patch by Simonas Kazlauskas!
Differential Revision: https://reviews.llvm.org/D50310
llvm-svn: 339922
This patch refactors the existing TargetLowering::BuildSDIV base implementation to support non-uniform constant vector denominators.
This is the last patch necessary to close PR36545
Differential Revision: https://reviews.llvm.org/D50765
llvm-svn: 339908
This patch fixes PR38125.
Instruction extension types are recorded in PromotedInsts, it can be used later in function canGetThrough. If an instruction has two users with different extension types, it will be inserted into PromotedInsts two times in function promoteOperandForOther. The second one overwrites the first one, and the final extension type is wrong, later causes problem in canGetThrough.
This patch changes the simple bool extension type to 2-bit enum type, add a BothExtension type in addition to zero/sign extension. When an user sees BothExtension for an instruction, it actually knows nothing about how that instruction is extended.
Differential Revision: https://reviews.llvm.org/D49512
llvm-svn: 339822
Subregister liveness applies selectively to register classes with certain
properties. Make sure that when it's enabled, it applies to a given virtual
register (in virtual register rewriter).
llvm-svn: 339784
This patch refactors the existing BuildExactSDIV implementation to support non-uniform constant vector denominators.
Differential Revision: https://reviews.llvm.org/D50392
llvm-svn: 339756
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.
Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.
This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.
This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.
As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]
Differential Revision: https://reviews.llvm.org/D50680
llvm-svn: 339740
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.
To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.
Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)
Differential Revision: https://reviews.llvm.org/D50667
llvm-svn: 339734
Flags in DIBasicType will be used to pass attributes used in
DW_TAG_base_type, such as DW_AT_endianity.
Patch by Chirag Patel!
Differential Revision: https://reviews.llvm.org/D49610
llvm-svn: 339714
There are two forms for label debug information in DWARF format.
1. Labels in a non-inlined function:
DW_TAG_label
DW_AT_name
DW_AT_decl_file
DW_AT_decl_line
DW_AT_low_pc
2. Labels in an inlined function:
DW_TAG_label
DW_AT_abstract_origin
DW_AT_low_pc
We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.
The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.
We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.
It also generates label debug information under global isel.
Differential Revision: https://reviews.llvm.org/D45556
llvm-svn: 339676
Fix SelectionDAG::computeKnownBits asserting when handling EXTRACT_SUBVECTOR
when zero extending the demanded elements mask if it is already as long as the
source vector.
Differential Revision: https://reviews.llvm.org/D49574
llvm-svn: 339600
This is another variation of PR38533. In this case, the result type of the bitcast is legal and 16-bits wide, but not a scalar integer. So we need to emit the convert to i16 and then bitcast it to the true result type. This new bitcast will be further type legalized if necessary.
llvm-svn: 339536
Previously if the result type was a vector, we emitted a FP_TO_FP16 with a vector result type which isn't valid.
This is basically the opposite case of the root cause of PR38533.
llvm-svn: 339535
Fixes PR37524.
The exception handling encodings for x86_64 in kernel code model
has been changed with r309884. Restore it to correct ones. These
encodings include PersonalityEncoding, LSDAEncoding and
TTypeEncoding.
Differential Revision: https://reviews.llvm.org/D50490
llvm-svn: 339534
We were checking for all bits being Known by checking Known.Zero|Known.One, but if all the bits are known then the value should be a Constant and we can just check for that instead.
llvm-svn: 339509
The previous name sounds like it inserts cfguard implementation, but it
really just emits the table of address-taken functions. Change the name
to better reflect that.
Clang will be updated in the next commit.
llvm-svn: 339419
Summary:
The TType encoding, LSDA encoding, and personality encoding are all
passed explicitly by CodeGen to the assembler through .cfi_* directives,
so only the AsmPrinter needs to know about them.
The FDE CFI encoding however, controls the encoding of the label
implicitly created by the .cfi_startproc directive. That directive seems
to be special in that it doesn't take an encoding, so the assembler just
has to know how to encode one DSO-local label reference from .eh_frame
to .text.
As a result, it looks like MC will continue to have to know when the
large code model is in use. Perhaps we could invent a '.cfi_startproc
[large]' flag so that this knowledge doesn't need to pollute the
assembler.
Reviewers: davide, lliu0, JDevlieghere
Subscribers: hiraditya, fedor.sergeev, llvm-commits
Differential Revision: https://reviews.llvm.org/D50533
llvm-svn: 339397
Similar to rL337966 - if the DAGCombiner's rotate matching was
working as expected, I don't think we'd see any test diffs here.
AArch only goes right, and PPC only goes left.
x86 has both, so no diffs there.
Differential Revision: https://reviews.llvm.org/D50091
llvm-svn: 339359
Summary: This change provides a common optimization path for both Unsafe and FMF driven optimization for this fsub fold adding reassociation, as it the flag that most closely represents the translation
Reviewers: spatel, wristow, arsenm
Reviewed By: spatel
Subscribers: wdng
Differential Revision: https://reviews.llvm.org/D50195
llvm-svn: 339357
Summary:
The interface to get size and spill size of a register
was moved from MCRegisterInfo to TargetRegisterInfo over
a year ago. Afaik the old interface has bee around
to give out-of-tree targets a chance to adapt to the
new interface.
One problem with the old MCRegisterClass::PhysRegSize was that
it represented the size of a register as "size in bits" / 8.
So a register had to be a multiple of eight bits wide for the
size to be correct (and the byte size for the target needed to
be eight bits).
Reviewers: kparzysz, qcolombet
Reviewed By: kparzysz
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47199
llvm-svn: 339350
isNegatibleForFree() should not matter here (as the test diffs show)
because it's always a win to replace an fsub+fadd with fneg. The
problem in D50195 persists because either (1) we are doing these
folds in the wrong order or (2) we're missing another fold for fadd.
llvm-svn: 339299
I don't know if it's possible to expose this diff in a test,
but we should always try simplifications (no new nodes created)
before more complicated transforms for efficiency (similar to
what we do in IR).
llvm-svn: 339298
When using APPLE extensions, don't duplicate the compiler invocation's
flags both in AT_producer and AT_APPLE_flags.
Differential revision: https://reviews.llvm.org/D50453
llvm-svn: 339268
The isConstOrConstSplat result is only used in a ISD::matchUnaryPredicate call which can perform the equivalent iteration just as quickly.
llvm-svn: 339262
Summary:
Currently, in line with GCC, when specifying reserved registers like sp or pc on an inline asm() clobber list, we don't always preserve the original value across the statement. And in general, overwriting reserved registers can have surprising results.
For example:
```
extern int bar(int[]);
int foo(int i) {
int a[i]; // VLA
asm volatile(
"mov r7, #1"
:
:
: "r7"
);
return 1 + bar(a);
}
```
Compiled for thumb, this gives:
```
$ clang --target=arm-arm-none-eabi -march=armv7a -c test.c -o - -S -O1 -mthumb
...
foo:
.fnstart
@ %bb.0: @ %entry
.save {r4, r5, r6, r7, lr}
push {r4, r5, r6, r7, lr}
.setfp r7, sp, #12
add r7, sp, #12
.pad #4
sub sp, #4
movs r1, #7
add.w r0, r1, r0, lsl #2
bic r0, r0, #7
sub.w r0, sp, r0
mov sp, r0
@APP
mov.w r7, #1
@NO_APP
bl bar
adds r0, #1
sub.w r4, r7, #12
mov sp, r4
pop {r4, r5, r6, r7, pc}
...
```
r7 is used as the frame pointer for thumb targets, and this function needs to restore the SP from the FP because of the variable-length stack allocation a. r7 is clobbered by the inline assembly (and r7 is included in the clobber list), but LLVM does not preserve the value of the frame pointer across the assembly block.
This type of behavior is similar to GCC's and has been discussed on the bugtracker: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=11807 . No consensus seemed to have been reached on the way forward. Clang behavior has briefly been discussed on the CFE mailing (starting here: http://lists.llvm.org/pipermail/cfe-dev/2018-July/058392.html). I've opted for following Eli Friedman's advice to print warnings when there are reserved registers on the clobber list so as not to diverge from GCC behavior for now.
The patch uses MachineRegisterInfo's target-specific knowledge of reserved registers, just before we convert the inline asm string in the AsmPrinter.
If we find a reserved register, we print a warning:
```
repro.c:6:7: warning: inline asm clobber list contains reserved registers: R7 [-Winline-asm]
"mov r7, #1"
^
```
Reviewers: eli.friedman, olista01, javed.absar, efriedma
Reviewed By: efriedma
Subscribers: efriedma, eraman, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D49727
llvm-svn: 339257
Provide a pass-through of the numerator for divide by one cases - this is the same approach we take in DAGCombiner::visitSDIVLike.
I investigated whether we could achieve this by magic MULHU/SRL values but nothing appeared to work as we don't have a way for MULHU(x,c) -> x
llvm-svn: 339254
As requested in D50392, this is a minor refactor to BuildExactSDIV to stop taking the uniform constant APInt divisor and instead extract it locally.
I also cleanup the operands and valuetypes to better match BuildUDiv (and BuildSDIV in the near future).
llvm-svn: 339246
Summary: Extend fix for PR34170 to support inline assembly with multiple output operands that do not naturally go in the register class it is constrained to (eg. double in a 32-bit GPR as in the PR).
Reviewers: bogner, t.p.northover, lattner, javed.absar, efriedma
Reviewed By: efriedma
Subscribers: efriedma, tra, eraman, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D45437
llvm-svn: 339225
Scatter could have multiple identical indices. We need to maintain sequential order. We get this right in LegalizeVectorTypes, but not in this code.
Differential Revision: https://reviews.llvm.org/D50374
llvm-svn: 339157
This was missed in D50185.
NFC until we add actual non-uniform support to BuildSDIV (similar BuildUDIV support in D49248) - for now it just early outs.
llvm-svn: 339147
This fixes an inconsistency in code generation when compiling with or
without debug information (-g). When debug information is available in
an empty block, the original test would fail, resulting in possibly
different code.
Patch by: Jeroen Dobbelaere
Differential revision: https://reviews.llvm.org/D49467
llvm-svn: 339129
Summary:
The accelerator tables use the debug_str section to store their strings.
However, they do not support the indirect method of access that is
available for the debug_info section (DW_FORM_strx et al.).
Currently our code is assuming that all strings can/will be referenced
indirectly, and puts all of them into the debug_str_offsets section.
This is generally true for regular (unsplit) dwarf, but in the DWO case,
most of the strings in the debug_str section will only be used from the
accelerator tables. Therefore the contents of the debug_str_offsets
section will be largely unused and bloating the main executable.
This patch rectifies this by teaching the DwarfStringPool to
differentiate between strings accessed directly and indirectly. When a
user inserts a string into the pool it has to declare whether that
string will be referenced directly or not. If at least one user requsts
indirect access, that string will be assigned an index ID and put into
debug_str_offsets table. Otherwise, the offset table is skipped.
This approach reduces the overall binary size (when compiled with
-gdwarf-5 -gsplit-dwarf) in my tests by about 2% (debug_str_offsets is
shrunk by 99%).
Reviewers: probinson, dblaikie, JDevlieghere
Subscribers: aprantl, mgrang, llvm-commits
Differential Revision: https://reviews.llvm.org/D49493
llvm-svn: 339122
This patch refactors the existing TargetLowering::BuildUDIV base implementation to support non-uniform constant vector denominators.
It also includes a fold for MULHU by pow2 constants to SRL which can now more readily occur from BuildUDIV.
Differential Revision: https://reviews.llvm.org/D49248
llvm-svn: 339121
Src0 doesn't really convey any meaning to what the operand is. Passthru matches what's used in the documentation for the intrinsic this comes from.
llvm-svn: 339101
This assert fires when attempting to extract a subregister from the
global PIC base register. This virtual register SD node is not in the
VRBaseMap, so we shouldn't call getVR to look it up there. If this is a
RegisterSDNode, we should be able to use the virtual register directly.
Fixes PR38385
llvm-svn: 339056
for all the uses from the same def is done.
We run into a compile time problem with flex generated code combined with
`-fno-jump-tables`. The cause is that machineLICM hoists a lot of invariants
outside of a big loop, and drastically increases the compile time in global
register splitting and copy coalescing. https://reviews.llvm.org/D49353
relieves the problem in global splitting. This patch is to handle the problem
in copy coalescing.
About the situation where the problem in copy coalescing happens. After
machineLICM, we have several defs outside of a big loop with hundreds or
thousands of uses inside the loop. Rematerialization in copy coalescing
happens for each use and everytime rematerialization is done, shrinkToUses
will be called to update the huge live interval. Because we have 'n' uses
for a def, and each live interval update will have at least 'n' complexity,
the total update work is n^2.
To fix the problem, we try to do the live interval update work in a collective
way. If a def has many copylike uses larger than a threshold, each time
rematerialization is done for one of those uses, we won't do the live interval
update in time but delay that work until rematerialization for all those uses
are completed, so we only have to do the live interval update work once.
Delaying the live interval update could potentially change the copy coalescing
result, so we hope to limit that change to those defs with many
(like above a hundred) copylike uses, and the cutoff can be adjusted by the
option -mllvm -late-remat-update-threshold=xxx.
Differential Revision: https://reviews.llvm.org/D49519
llvm-svn: 339035
In the past, DbgInfoIntrinsic has a strong assumption that these
intrinsics all have variables and expressions attached to them.
However, it is too strong to derive the class for other debug entities.
Now, it has problems for debug labels.
In order to make DbgInfoIntrinsic as a base class for 'debug info', I
create a class for 'variable debug info', DbgVariableIntrinsic.
DbgDeclareInst, DbgAddrIntrinsic, and DbgValueInst will be derived from it.
Differential Revision: https://reviews.llvm.org/D50220
llvm-svn: 338984
Add a parameter for testing specifically for
sNaNs - at least one instruction pattern on AMDGPU
needs to check specifically for this.
Also handle more cases, and add a target hook
for custom nodes, similar to the hooks for known
bits.
llvm-svn: 338910
First step towards a BuildSDIV equivalent to D49248 for non-uniform vector support - this just pushes the splat detection down into TargetLowering::BuildSDIV where its still used.
Differential Revision: https://reviews.llvm.org/D50185
llvm-svn: 338838
At least on ELF, it's impossible to tell from the object file whether
two globals with the same section marking were merged: the merged global
uses "private" linkage to hide its symbol, and the aliases look like
regular symbols. I can't think of any other reason to disallow it.
(Of course, we can only merge globals in the same section.)
The weird alignment handling matches AsmPrinter; our alignment handling
for global variables should probably be refactored.
Differential Revision: https://reviews.llvm.org/D49822
llvm-svn: 338791
In expansion of FCOPYSIGN, the shift node is missing when the two
operands of FCOPYSIGN are of the same size. We should always generate
shift node (if the required shift bit is not zero) to put the sign
bit into the right position, regardless of the size of underlying
types.
Differential Revision: https://reviews.llvm.org/D49973
llvm-svn: 338665
AArch64 ELF ABI does not define a static relocation type for TLS offset within
a module, which makes it impossible for compiler to generate a valid
DW_AT_location content for thread local variables. Currently LLVM generates an
invalid R_AARCH64_ABS64 relocation at the DW_AT_location field for a TLS
variable. That causes trouble for linker because thread local variable does
not have an absolute address at link time. AArch64 GCC solves the problem by
not generating DW_AT_location for thread local variables. We should do the
same in LLVM.
Differential Revision: https://reviews.llvm.org/D43860
llvm-svn: 338655
Summary:
Added an option that allows to emit only '.loc' and '.file' kind debug
directives, but disables emission of the DWARF sections. Required for
NVPTX target to support profiling. It requires '.loc' and '.file'
directives, but does not require any DWARF sections for the profiler.
Reviewers: probinson, echristo, dblaikie
Subscribers: aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46021
llvm-svn: 338616
The bug is visible in the constant-folded x86 tests. We can't use the
negated shift amount when the type is not power-of-2:
https://rise4fun.com/Alive/US1r
...so in that case, use the regular lowering that includes a select
to guard against a shift-by-bitwidth. This path is improved by only
calculating the modulo shift amount once now.
Also, improve the rotate (with power-of-2 size) lowering to use
a negate rather than subtract from bitwidth. This improves the
codegen whether we have a rotate instruction or not (although
we can still see that we're not matching to a legal rotate in
all cases).
llvm-svn: 338592
There is nothing x86-specific about this code, so it'd be nice to make this available for other targets to use in the future (and get it out of X86ISelLowering!).
Differential Revision: https://reviews.llvm.org/D50083
llvm-svn: 338586
Getting the DWARF types section is only implemented for ELF object
files. We already disabled emitting debug types in clang (r337717), but
now we also report an fatal error (rather than crashing) when trying to
obtain this section in MC. Additionally we ignore the generate debug
types flag for unsupported target triples.
See PR38190 for more information.
Differential revision: https://reviews.llvm.org/D50057
llvm-svn: 338527
This revision implements support for generating DWARFv5 .debug_addr section.
The implementation is pretty straight-forward: we just check the dwarf version
and emit section header if needed.
Reviewers: aprantl, dblaikie, probinson
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D50005
llvm-svn: 338487
Previously we were just visiting the blocks in the function in IR order, which
is rather arbitrary. Therefore we wouldn't always visit defs before uses, but
the translation code relies on this assumption in some places.
Only codegen change seen in tests is an elision of a redundant copy.
Fixes PR38396
llvm-svn: 338476
Call shouldOutlineFromFunctionByDefault, isFunctionSafeToOutlineFrom,
getOutliningType, and getMachineOutlinerMBBFlags using the correct
TargetInstrInfo. And don't create a MachineFunction for a function
declaration.
The call to getOutliningCandidateInfo is still a little weird, but at
least the weirdness is explicitly called out.
Differential Revision: https://reviews.llvm.org/D49880
llvm-svn: 338465
Correct the address space for the inserted argument
stack slot.
AMDGPU seems to not do anything with this information,
so I don't think this was breaking anything.
llvm-svn: 338428
There are two forms for label debug information in DWARF format.
1. Labels in a non-inlined function:
DW_TAG_label
DW_AT_name
DW_AT_decl_file
DW_AT_decl_line
DW_AT_low_pc
2. Labels in an inlined function:
DW_TAG_label
DW_AT_abstract_origin
DW_AT_low_pc
We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.
The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.
We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.
It also generates label debug information under global isel.
Differential Revision: https://reviews.llvm.org/D45556
llvm-svn: 338390