These simplifications were previously enabled only with isFast(), but that
is more restrictive than required. Since r317488, FMF has 'reassoc' to
control these cases at a finer level.
llvm-svn: 330089
As demonstrated by the regression tests added in this patch, the
following cases are valid cases:
1. A Function with no DISubprogram attached, but various debug info
related to its instructions, coming, for instance, from an inlined
function, also defined somewhere else in the same module;
2. ... or coming exclusively from the functions inlined and eliminated
from the module entirely.
The ValueMap shared between CloneFunctionInto calls within CloneModule
needs to contain identity mappings for all of the DISubprogram's to
prevent them from being duplicated by MapMetadata / RemapInstruction
calls, this is achieved via DebugInfoFinder collecting all the
DISubprogram's. However, CloneFunctionInto was missing calls into
DebugInfoFinder for functions w/o DISubprogram's attached, but still
referring DISubprogram's from within (case 1). This patch fixes that.
The fix above, however, exposes another issue: if a module contains a
DISubprogram referenced only indirectly from other debug info
metadata, but not attached to any Function defined within the module
(case 2), cloning such a module causes a DICompileUnit duplication: it
will be moved in indirecty via a DISubprogram by DebugInfoFinder first
(because of the first bug fix described above), without being
self-mapped within the shared ValueMap, and then will be copied during
named metadata cloning. So this patch makes sure DebugInfoFinder
visits DICompileUnit's referenced from DISubprogram's as it goes w/o
re-processing llvm.dbg.cu list over and over again for every function
cloned, and makes sure that CloneFunctionInto self-maps
DICompileUnit's referenced from the entire function, not just its own
DISubprogram attached that may also be missing.
The most convenient way of tesing CloneModule I found is to rely on
CloneModule call from `opt -run-twice`, instead of writing tedious
unit tests. That feature has a couple of properties that makes it hard
to use for this purpose though:
1. CloneModule doesn't copy source filename, making `opt -run-twice`
report it as a difference.
2. `opt -run-twice` does the second run on the original module, not
its clone, making the result of cloning completely invisible in opt's
actual output with and without `-run-twice` both, which directly
contradicts `opt -run-twice`s own error message.
This patch fixes this as well.
Reviewed By: aprantl
Reviewers: loladiro, GorNishanov, espindola, echristo, dexonsmith
Subscribers: vsk, debug-info, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D45593
llvm-svn: 330069
The function getMinimumVF(ElemWidth) will return the minimum VF for
a vector with elements of size ElemWidth bits. This value will only
apply to targets for which TTI::shouldMaximizeVectorBandwidth returns
true. The value of 0 indicates that there is no minimum VF.
Differential Revision: https://reviews.llvm.org/D45271
llvm-svn: 330062
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: kcc, pcc, danielcdh, jmolloy, sanjoy, dberlin, ruiu
Reviewed By: ruiu
Subscribers: ruiu, llvm-commits
Differential Revision: https://reviews.llvm.org/D45142
llvm-svn: 330059
Summary:
The fold added in D45108 did not account for the fact that
the and instruction is commutative, and if the mask is a variable,
the mask variable and the fold variable may be swapped.
I have noticed this by accident when looking into [[ https://bugs.llvm.org/show_bug.cgi?id=6773 | PR6773 ]]
This extends/generalizes that fold, so it is handled too.
Reviewers: spatel, craig.topper
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45539
llvm-svn: 330001
This completes the work started in r329604 and r329605 when we changed clang to no longer use the intrinsics.
We lost some InstCombine SimplifyDemandedBit optimizations through this change as we aren't able to fold 'and', bitcast, shuffle very well.
llvm-svn: 329990
Created a helper function to query for non negative SCEVs. Uses the
SGE predicate to catch constants that could be interpreted as
negative.
Differential Revision: https://reviews.llvm.org/D45481
llvm-svn: 329907
We're already removing allocsize attributes from Functions that we
remove args from, since removing arguments from a function may make the
allocsize attribute incorrect. It appears we forgot to also remove them
from callsites.
Without this, I get verifier errors on `@Test2`.
It probably wouldn't be too hard to make DAE properly update allocsize
attributes instead of dropping them, but I can't think of a scenario
where that'd be useful in practice.
llvm-svn: 329868
The standard says that the order of evaluation of an expression
s[x] = foo()
is unspecified. In our case, we first create an empty entry in the map,
then call foo(), then store its return value to the created entry. The
problem is that foo uses the map as a cache, so if it finds that there
is an entry in the map, it stops computation. This change explicitly
sets the order, thus fixing this heisenbug.
llvm-svn: 329864
With -fno-plt, for example, calls to printf when getting converted to puts
still use the PLT. This patch checks for the metadata "RtLibUseGOT" and
annotates the declaration with the right attributes.
Differential Revision: https://reviews.llvm.org/D45180
llvm-svn: 329768
This is based on an example that was recently posted on llvm-dev:
void *propagate_null(void* b, int* g) {
if (!b) {
return 0;
}
(*g)++;
return b;
}
https://godbolt.org/g/xYk3qG
The original code or constant propagation in other passes has obscured the fact
that the phi can be removed completely.
Differential Revision: https://reviews.llvm.org/D45448
llvm-svn: 329755
Summary:
Another clean up, following D43208.
Interleaved memory access analysis/optimization has nothing to do with vectorization legality. It doesn't really belong there. On the other hand, cost model certainly has to know about it.
In principle, vectorization should proceed like Legality ==> Optimization ==> CostModel ==> CodeGen, and this change just does that,
by moving the interleaved access analysis/decision out of Legal, and run it just before CostModel object is created.
After this, I can move LoopVectorizationLegality and Hints/Requirements classes into it's own header file, making it shareable within Transform tree. I have the patch already but I don't want to mix with this change. Eventual goal is to move to Analysis tree, but I first need to move RecurrenceDescriptor/InductionDescriptor from Transform/Util/LoopUtil.* to Analysis.
Reviewers: rengolin, hfinkel, mkuper, dcaballe, sguggill, fhahn, aemerson
Reviewed By: rengolin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45072
llvm-svn: 329645
Summary:
SSAUpdater is a bottleneck in JumpThreading, and this patch improves the
situation by using SSAUpdaterBulk instead.
Compile time impact: no noticable changes on CTMark, a big improvement
on the test from PR16756.
Reviewers: dberlin, davide, MatzeB
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D44282
llvm-svn: 329644
Summary:
SSAUpdater is a bottleneck in a number of passes, and one of the reasons
is that it performs a lot of unnecessary computations (DT/IDF) over and
over again. This patch adds a new SSAUpdaterBulk that uses existing DT
and avoids recomputing IDF when possible.
Reviewers: dberlin, davide, MatzeB
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D44282
llvm-svn: 329643
Without the fast math flags, the llvm.experimental.vector.reduce.fadd/fmul intrinsic expansions must be expanded in order.
This patch scalarizes the reduction, applying the accumulator at the start of the sequence: ((((Acc + Scl[0]) + Scl[1]) + Scl[2]) + ) ... + Scl[NumElts-1]
Differential Revision: https://reviews.llvm.org/D45366
llvm-svn: 329585
Summary:
We do not try to move the instructions and split the block till we
know the blocks can be split, i.e. BCE-cmp-insts can be separated from
non-BCE-cmp-insts.
Reviewers: davide, courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44443
llvm-svn: 329564
In IRCE, we have a very old legacy check that works when we collect comparisons that we
treat as range checks. It ensures that the value against which the indvar is compared is
loop invariant and is also positive.
This latter condition remained there since the times when IRCE was only able to handle
signed latch comparison. As the optimization evolved, it now learned how to intersect
signed or unsigned ranges, and this logic has no reliance on the fact that the right border
of each range should be positive.
The old implementation of this non-negativity check was also naive enough and just looked
into ranges (while most of other IRCE logic tries to use power of SCEV implications), so this
check did not allow to deal with the most simple case that looks like follows:
int size; // not known non-negative
int length; //known non-negative;
i = 0;
if (size != 0) {
do {
range_check(i < size);
range_check(i < length);
++i;
} while (i < size)
}
In this case, even if from some dominating conditions IRCE could parse loop
structure, it could only remove the range check against `length` and simply
ignored the check against `size`.
In this patch we remove this obsolete check. It will allow IRCE to pick comparison
against `size` as a potential range check and then let Range Intersection logic
decide whether it is OK to eliminate it or not.
Differential Revision: https://reviews.llvm.org/D45362
Reviewed By: samparker
llvm-svn: 329547
Summary:
Fixing an issue where initializations of globals where constructors use
casts were silently translated to 0-initialization.
Reviewers: davidxl, evgeny777
Reviewed By: evgeny777
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45198
llvm-svn: 329409
Inserting instrumentation between a musttail call and ret instruction
would create invalid IR. Instead, treat musttail calls as function
exits.
llvm-svn: 329385
This restores what was lost with rL73243 but without
re-introducing the bug that was present in the old code.
Note that we already have these transforms if the ops are
marked 'fast' (and I assume that's happening somewhere in
the code added with rL170471), but we clearly don't need
all of 'fast' for these transforms.
llvm-svn: 329362
Summary:
This is a fix to PR37005.
Essentially, rL328539 ([InstCombine] reassociate loop invariant GEP chains to enable LICM) contains a bug
whereby it will convert:
%src = getelementptr inbounds i8, i8* %base, <2 x i64> %val
%res = getelementptr inbounds i8, <2 x i8*> %src, i64 %val2
into:
%src = getelementptr inbounds i8, i8* %base, i64 %val2
%res = getelementptr inbounds i8, <2 x i8*> %src, <2 x i64> %val
By swapping the index operands if the GEPs are in a loop, and %val is loop variant while %val2
is loop invariant.
This fix recreates new GEP instructions if the index operand swap would result in the type
of %src changing from vector to scalar, or vice versa.
Reviewers: sebpop, spatel
Reviewed By: sebpop
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45287
llvm-svn: 329331
LoopInterchange relies on LoopInfo being up-to-date, so we should
preserve it after interchanging. This patch updates restructureLoops to
move the BBs of the interchanged loops to the right place.
Reviewers: davide, efriedma, karthikthecool, mcrosier
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D45278
llvm-svn: 329264
Summary:
If the callsite is inside landing pad, do not perform callsite splitting.
Callsite splitting uses utility function llvm::DuplicateInstructionsInSplitBetween, which eventually calls llvm::SplitEdge. llvm::SplitEdge calls llvm::SplitCriticalEdge with an assumption that the function returns nullptr only when the target edge is not a critical edge (and further assumes that if the return value was not nullptr, the predecessor of the original target edge always has a single successor because critical edge splitting was successful). However, this assumtion is not true because SplitCriticalEdge returns nullptr if the destination block is a landing pad. This invalid assumption results assertion failure.
Fundamental solution might be fixing llvm::SplitEdge to not to rely on the invalid assumption. However, it'll involve a lot of work because current API assumes that llvm::SplitEdge never fails. Instead, this patch makes callsite splitting to not to attempt splitting if the callsite is in a landing pad.
Attached test case will crash with assertion failure without the fix.
Reviewers: fhahn, junbuml, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45130
llvm-svn: 329250
Sometimes instead of storing addresses as is, the kernel stores the address of
a page and an offset within that page, and then computes the actual address
when it needs to make an access. Because of this the pointer tag gets lost
(gets set to 0xff). The solution is to ignore all accesses tagged with 0xff.
This patch adds a -hwasan-match-all-tag flag to hwasan, which allows to ignore
accesses through pointers with a particular pointer tag value for validity.
Patch by Andrey Konovalov.
Differential Revision: https://reviews.llvm.org/D44827
llvm-svn: 329228
Fixes cases like the new test @nonuniform. In that test, %cc itself
is a uniform value; however, when reading it after the end of the loop in
basic block %if, its value is effectively non-uniform, so the branch is
non-uniform.
This problem was encountered in
https://bugs.freedesktop.org/show_bug.cgi?id=103743; however, this change
in itself is not sufficient to fix that bug, as there is another issue
in the AMDGPU backend.
As discovered after committing an earlier version of this change, this
exposes a subtle interaction between this pass and DivergenceAnalysis:
since we remove and re-create branch instructions, we can no longer rely
on DivergenceAnalysis for branches in subregions that were already
processed by the pass.
Explicitly remove branch instructions from DivergenceAnalysis to
avoid dangling pointers as a matter of defensive programming, and
change how we detect non-uniform subregions.
Change-Id: I32bbffece4a32f686fab54964dae1a5dd72949d4
Differential Revision: https://reviews.llvm.org/D43743
llvm-svn: 329165
Summary:
Currently merge conditional stores can't handle cases where PostBB (the block we need to move the store to) has more than 2 predecessors.
This patch removes that restriction by creating a new block with only the 2 predecessors we care about and an unconditional branch to the original block. This provides a place to put the store.
Reviewers: efriedma, jmolloy, ABataev
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39760
llvm-svn: 329142
The tests marked with 'FIXME' require loosening the check
in SimplifyAssociativeOrCommutative() to optimize completely;
that's still checking isFast() in Instruction::isAssociative().
llvm-svn: 329121
Summary:
If an alloca need to be stored in the coroutine frame and it has an alignment specified and the alignment does not match the natural alignment of the alloca type. Insert appropriate padding into the coroutine frame to make sure that it gets requested alignment.
For example for a packet type (which natural alignment is 1), but alloca alignment is 8, we may need to insert a padding field with required number of bytes to make sure it is properly aligned.
```
%PackedStruct = type <{ i64 }>
...
%data = alloca %PackedStruct, align 8
```
If the previous field in the coroutine frame had alignment 2, we would have [6 x i8] inserted before %PackedStruct in the coroutine frame:
```
%f.Frame = type { ..., i16, [6 x i8], %PackedStruct }
```
Reviewers: rnk, lewissbaker, modocache
Reviewed By: modocache
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D45221
llvm-svn: 329112
It also updates test/Transforms/LoopInterchange/call-instructions.ll
to use accesses where we can prove dependence after D35430.
Reviewers: sebpop, karthikthecool, blitz.opensource
Reviewed By: sebpop
Differential Revision: https://reviews.llvm.org/D45206
llvm-svn: 329111
Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.
Reviewers: pcc, kcc, kubamracek
Reviewed By: pcc, kcc
Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D44800
llvm-svn: 329108
Summary:
Folding patterns like:
%vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
%cast = bitcast <4 x i8> %vec to i32
%cond = icmp eq i32 %cast, 0
into:
%ext = extractelement <4 x i8> %insvec, i32 0
%cond = icmp eq i32 %ext, 0
Combined with existing rules, this allows us to fold patterns like:
%insvec = insertelement <4 x i8> undef, i8 %val, i32 0
%vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
%cast = bitcast <4 x i8> %vec to i32
%cond = icmp eq i32 %cast, 0
into:
%cond = icmp eq i8 %val, 0
When we construct a splat vector via a shuffle, and bitcast the vector into an integer type for comparison against an integer constant. Then we can simplify the the comparison to compare the splatted value against the integer constant.
Reviewers: spatel, anna, mkazantsev
Reviewed By: spatel
Subscribers: efriedma, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D44997
llvm-svn: 329087
Summary:
If the load/extractelement/extractvalue instructions are not originally
consecutive, the SLP vectorizer is unable to vectorize them. Patch
allows reordering of such instructions.
Patch does not support reordering of the repeated instruction, this must
be handled in the separate patch.
Reviewers: RKSimon, spatel, hfinkel, mkuper, Ayal, ashahid
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43776
llvm-svn: 329085
The primary issue here is that using NDEBUG alone isn't enough to guard
debug printing -- instead the DEBUG() macro needs to be used so that the
specific pass debug logging check is employed. Without this, every
asserts-enabled build was printing out information when it hit this.
I also fixed another place where we had multiple statements in a DEBUG
macro to use {}s to be a bit cleaner. And I fixed a place that used
errs() rather than dbgs().
llvm-svn: 329082
The default assembly handling mode may introduce false positives in the
cases when MSan doesn't understand that the assembly call initializes
the memory pointed to by one of its arguments.
We introduce the conservative mode, which initializes the first
|sizeof(type)| bytes for every |type*| pointer passed into the
assembly statement.
llvm-svn: 329054
The primary issue here is that using NDEBUG alone isn't enough to guard
debug printing -- instead the DEBUG() macro needs to be used so that the
specific pass debug logging check is employed. Without this, every
asserts-enabled build was printing out information when it hit this.
I also fixed another place where we had multiple statements in a DEBUG
macro to use {}s to be a bit cleaner. And I fixed a place that used
`errs()` rather than `dbgs()`.
llvm-svn: 329046
For Hexagon, peeling loops with small runtime trip count is beneficial for our
benchmarks. We set PeelCount in HexagonTargetInfo.cpp and we use PeelCount set
by the target for computing the desired peel count.
Differential Revision: https://reviews.llvm.org/D44880
llvm-svn: 329042
We use two approaches for determining the minimum bitwidth.
* Demanded bits
* Value tracking
If demanded bits doesn't result in a narrower type, we then try value tracking.
We need this if we want to root SLP trees with the indices of getelementptr
instructions since all the bits of the indices are demanded.
But there is a missing piece though. We need to be able to distinguish "demanded
and shrinkable" from "demanded and not shrinkable". For example, the bits of %i
in
%i = sext i32 %e1 to i64
%gep = getelementptr inbounds i64, i64* %p, i64 %i
are demanded, but we can shrink %i's type to i32 because it won't change the
result of the getelementptr. On the other hand, in
%tmp15 = sext i32 %tmp14 to i64
%tmp16 = insertvalue { i64, i64 } undef, i64 %tmp15, 0
it doesn't make sense to shrink %tmp15 and we can skip the value tracking.
Ideas are from Matthew Simpson!
Differential Revision: https://reviews.llvm.org/D44868
llvm-svn: 329035
Summary:
When attempting to split a coroutine with 'hidden' visibility (for
example, a C++ coroutine that is inlined when compiled with the option
'-fvisibility-inlines-hidden'), LLVM would hit an assertion in
include/llvm/IR/GlobalValue.h:240: "local linkage requires default
visibility". The issue is that the visibility is copied from the source
of the function split in the `CloneFunctionInto` function, but the linkage
is not. To fix, create the new function first with external linkage,
then copy the linkage from the original function *after* `CloneFunctionInto`
is called.
Since `GlobalValue::setLinkage` in turn calls `maybeSetDsoLocal`, the
explicit call to `setDSOLocal` can be removed in CoroSplit.cpp.
Test Plan: check-llvm
Reviewers: GorNishanov, lewissbaker, EricWF, majnemer, rnk
Reviewed By: rnk
Subscribers: llvm-commits, eric_niebler
Differential Revision: https://reviews.llvm.org/D44185
llvm-svn: 329033
Summary:
The cast simplifications that instcombine does here do not make any
attempt to obey the verifier rules for musttail calls. Therefore we have
to disable them.
Reviewers: efriedma, majnemer, pcc
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D45186
llvm-svn: 329027
Some Function level metadatas, such as function entry count, are not cloned in
DeadArgumentElim. This happens a lot in lto/thinlto because of DeadArgumentElim
after internalization.
This patch clones the metadatas in the original function to the new function.
Differential Revision: https://reviews.llvm.org/D44127
llvm-svn: 328991
Summary:
A recent addition to Coroutines TS (https://wg21.link/p0913) adds a pre-defined coroutine noop_coroutine that does nothing.
To implement this feature, we implemented an llvm.coro.noop intrinsic that returns a coroutine handle to a coroutine that does nothing when resumed or destroyed.
Reviewers: EricWF, modocache, rnk, lewissbaker
Reviewed By: modocache
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45114
llvm-svn: 328986
Summary:
If the load/extractelement/extractvalue instructions are not originally
consecutive, the SLP vectorizer is unable to vectorize them. Patch
allows reordering of such instructions.
Reviewers: RKSimon, spatel, hfinkel, mkuper, Ayal, ashahid
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43776
llvm-svn: 328980
Summary:
Adds -import-cutoff=N which will stop importing during the thin link
after N imports. Default is -1 (no limit).
Reviewers: wmi
Subscribers: inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D45127
llvm-svn: 328934
If a loop has a loop exiting latch, it can be profitable
to rotate the loop if it leads to the simplification of
a phi node. Perform rotation in these cases even if loop
rotate itself didnt simplify the loop to get there.
Differential Revision: https://reviews.llvm.org/D44199
llvm-svn: 328933
This patch resolves link errors when the address of a static function is taken, and that function is uninstrumented by DFSan.
This change resolves bug 36314.
Patch by Sam Kerner!
Differential Revision: https://reviews.llvm.org/D44784
llvm-svn: 328890
For Hexagon, peeling loops with small runtime trip count is beneficial for our
benchmarks. We set PeelCount in HexagonTargetInfo.cpp and we use PeelCount set
by the target for computing the desired peel count.
Differential Revision: https://reviews.llvm.org/D44880
llvm-svn: 328854
In r312664 (D36404), JumpThreading stopped threading edges into
loop headers. Unfortunately, I observed a significant performance
regression as a result of this change. Upon further investigation,
the problematic pattern looked something like this (after
many high level optimizations):
while (true) {
bool cond = ...;
if (!cond) {
<body>
}
if (cond)
break;
}
Now, naturally we want jump threading to essentially eliminate the
second if check and hook up the edges appropriately. However, the
above mentioned change, prevented it from doing this because it would
have to thread an edge into the loop header.
Upon further investigation, what is happening is that since both branches
are threadable, JumpThreading picks one of them at arbitrarily. In my
case, because of the way that the IR ended up, it tended to pick
the one to the loop header, bailing out immediately after. However,
if it had picked the one to the exit block, everything would have
worked out fine (because the only remaining branch would then be folded,
not thraded which is acceptable).
Thus, to fix this problem, we can simply eliminate loop headers from
consideration as possible threading targets earlier, to make sure that
if there are multiple eligible branches, we can still thread one of
the ones that don't target a loop header.
Patch by Keno Fischer!
Differential Revision: https://reviews.llvm.org/D42260
llvm-svn: 328798
The existing LoopRotation.cpp is implemented as one of loop passes instead of
being a utility. The user cannot easily perform the loop rotation selectively
(or on demand) under different optimization level. For example, the loop
rotation is needed as part of the logic to convert a loop into a loop with
bottom test for a transformation. If the loop rotation is simply added as a
loop pass before the transformation, the pass is skipped if it is compiled at
–O0 or if it is explicitly disabled by the user, causing the compiler to
generate incorrect code. Furthermore, as a loop pass it will rotate all loops
instead of just the relevant loops.
We provide a utility interface for the loop rotation so that the loop rotation
can be called on demand. The changeset is as follows:
- Create a new file lib/Transforms/Utils/LoopRotationUtils.cpp and move the main
implementation of class LoopRotate into this file.
- Create a new file llvm/include/Transform/Utils/LoopRotationUtils.h with the
interface LoopRotation(...).
- Original LoopRotation.cpp is changed to use the utility function LoopRotation
in LoopRotationUtils.cpp. This is done in the same way community did for
mem-to-reg implementation.
Patch by Jin Lin!
Differential Revision: https://reviews.llvm.org/D44595
llvm-svn: 328766
Otherwise the definitions can't see the extern C declarations and get
name mangled, making it impossible for users to call them. This breaks
the Go bindings.
llvm-svn: 328765
This is a step towards the upcoming KMSAN implementation patch.
KMSAN is going to prepend a special basic block containing
tool-specific calls to each function. Because we still want to
instrument the original entry block, we'll need to store it in
ActualFnStart.
For MSan this will still be F.getEntryBlock(), whereas for KMSAN
it'll contain the second BB.
llvm-svn: 328697
This is a step towards the upcoming KMSAN implementation patch.
The isStore argument is to be used by getShadowOriginPtrKernel(),
it is ignored by getShadowOriginPtrUserspace().
Depending on whether a memory access is a load or a store, KMSAN
instruments it with different functions, __msan_metadata_ptr_for_load_X()
and __msan_metadata_ptr_for_store_X().
Those functions may return different values for a single address,
which is necessary in the case the runtime library decides to ignore
particular accesses.
llvm-svn: 328692
Fixed counter/weight overflow that leads to an assertion. Also fixed the help
string for pgo-emit-branch-prob option.
Differential Revision: https://reviews.llvm.org/D44809
llvm-svn: 328653
We check `canPeel` twice: when evaluating the number of iterations to be peeled
and within the method `peelLoop` that performs peeling. This method is only
executed if the calculated peel count is positive. Thus, the check in `peelLoop` can
never fail. This patch replaces this check with an assert.
Differential Revision: https://reviews.llvm.org/D44919
Reviewed By: fhahn
llvm-svn: 328615
As a follow-up to r328480, this updates the logic for the decreasing
safety checks in a similar manner:
- CanBeMax is replaced by CannotBeMaxInLoop which queries
isLoopEntryGuardedByCond on the maximum value.
- SumCanReachMin is replaced by isSafeDecreasingBound which includes
some logic from parseLoopStructure and, again, has been updated to
use isLoopEntryGuardedByCond on the given bounds.
Differential Revision: https://reviews.llvm.org/D44776
llvm-svn: 328613
This change brings performance of zlib up by 10%. The example below is from a
hot loop in longest_match() from zlib.
do.body:
%cur_match.addr.0 = phi i32 [ %cur_match, %entry ], [ %2, %do.cond ]
%idx.ext = zext i32 %cur_match.addr.0 to i64
%add.ptr = getelementptr inbounds i8, i8* %win, i64 %idx.ext
%add.ptr2 = getelementptr inbounds i8, i8* %add.ptr, i64 %idx.ext1
%add.ptr3 = getelementptr inbounds i8, i8* %add.ptr2, i64 -1
In this example %idx.ext1 is a loop invariant. It will be moved above the use of
loop induction variable %idx.ext such that it can be hoisted out of the loop by
LICM. The operands that have dependences carried by the loop will be sinked down
in the GEP chain. This patch will produce the following output:
do.body:
%cur_match.addr.0 = phi i32 [ %cur_match, %entry ], [ %2, %do.cond ]
%idx.ext = zext i32 %cur_match.addr.0 to i64
%add.ptr = getelementptr inbounds i8, i8* %win, i64 %idx.ext1
%add.ptr2 = getelementptr inbounds i8, i8* %add.ptr, i64 -1
%add.ptr3 = getelementptr inbounds i8, i8* %add.ptr2, i64 %idx.ext
llvm-svn: 328539
This replaces a large chunk of code that was looking for compound
patterns that include these sub-patterns. Existing tests ensure that
all of the previous examples are still folded as expected.
We still need to loosen the FMF check.
llvm-svn: 328502
Implement TTI interface for targets to indicate that the LSR should give
priority to post-incrementing addressing modes.
Combination of patches by Sebastian Pop and Brendon Cahoon.
Differential Revision: https://reviews.llvm.org/D44758
llvm-svn: 328490
Current logic of loop SCEV invalidation in Loop Unroller implicitly relies on
fact that exit count of outer loops cannot rely on exiting blocks of
inner loops, which is true in current implementation of backedge taken count
calculation but is wrong in general. As result, when we only forget the loop that
we have just unrolled, we may still have cached data for its outer loops (in particular,
exit counts) which keeps references on blocks of inner loop that could have been
changed or even deleted.
The attached test demonstrates a situaton when after unrolling of innermost loop
the outermost loop contains a dangling pointer on non-existant block. The problem
shows up when we apply patch https://reviews.llvm.org/D44677 that makes SCEV
smarter about exit count calculation. I am not sure if the bug exists without this patch,
it appears that now it is accidentally correct just because in practice exact backedge
taken count for outer loops with complex control flow inside is never calculated.
But when SCEV learns to do so, this problem shows up.
This patch replaces existing logic of SCEV loop invalidation with a correct one, which
happens to be invalidation of outermost loop (which also leads to invalidation of all
loops inside of it). It is the only way to ensure that no outer loop keeps dangling pointers
on removed blocks, or just outdated information that has changed after unrolling.
Differential Revision: https://reviews.llvm.org/D44818
Reviewed By: samparker
llvm-svn: 328483
CanBeMin is currently used which will report true for any unknown
values, but often a check is performed outside the loop which covers
this situation:
for (int i = 0; i < N; ++i)
...
if (N > 0)
for (int i = 0; i < N; ++i)
...
So I've add 'LoopGuardedAgainstMin' which reports whether N is
greater than the minimum value which then allows loop with a variable
loop count to be optimised. I've also moved the increasing bound
checking into its own function and replaced SumCanReachMax is another
isLoopEntryGuardedByCond function.
llvm-svn: 328480
Summary:
This was motivated by absence of PrunEH functionality in new PM.
It was decided that a proper way to do PruneEH is to add NoUnwind inference
into PostOrderFunctionAttrs and then perform normal SimplifyCFG on top.
This change generalizes attribute handling implemented for (a removal of)
Convergent attribute, by introducing a generic builder-like class
AttributeInferer
It registers all the attribute inference requests, storing per-attribute
predicates into a vector, and then goes through an SCC Node, scanning all
the instructions for not breaking attribute assumptions.
The main idea is that as soon all the instructions from all the functions
of SCC Node conform to attribute assumptions then we are free to infer
the attribute as set for all the functions of SCC Node.
It handles two distinct cases of attributes:
- those that might break due to derefinement of the function code
for these attributes we are allowed to apply inference only if all the
functions are "exact definitions". Example - NoUnwind.
- those that do not care about derefinement
for these attributes we are allowed to apply inference as soon as we see
any function definition. Example - removal of Convergent attribute.
Also in this commit:
* Converted all the FunctionAttrs tests to use FileCheck and added new-PM
invocations to them
* FunctionAttrs/convergent.ll test demonstrates a difference in behavior between
new and old PM implementations. Marked with FIXME.
* PruneEH tests were converted to new-PM as well, using function-attrs+simplify-cfg
combo as intended
* some of "other" tests were updated since function-attrs now infers 'nounwind'
even for old PM pipeline
* -disable-nounwind-inference hidden option added as a possible workaround for a supposedly
rare case when nounwind being inferred by default presents a problem
Reviewers: chandlerc, jlebar
Reviewed By: jlebar
Subscribers: eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D44415
llvm-svn: 328377
Summary:
Porting HWASan to Linux x86-64, first of the three patches, LLVM part.
The approach is similar to ARM case, trap signal is used to communicate
memory tag check failure. int3 instruction is used to generate a signal,
access parameters are stored in nop [eax + offset] instruction immediately
following the int3 one.
One notable difference is that x86-64 has to untag the pointer before use
due to the lack of feature comparable to ARM's TBI (Top Byte Ignore).
Reviewers: eugenis
Subscribers: kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D44699
llvm-svn: 328342
When building the SLP tree, we look for reuse among the vectorized tree
entries. However, each gather sequence is represented by a unique tree entry,
even though the sequence may be identical to another one. This means, for
example, that a gather sequence with two uses will be counted twice when
computing the cost of the tree. We should only count the cost of the definition
of a gather sequence rather than its uses. During code generation, the
redundant gather sequences are emitted, but we optimize them away with CSE. So
it looks like this problem just affects the cost model.
Differential Revision: https://reviews.llvm.org/D44742
llvm-svn: 328316
For comparisons with parameters, we can use the ParamState lattice
elements which also provide constant range information. This improves
the code for PR33253 further and gets us closer to use
ValueLatticeElement for all values.
Also, as we are using the range information in the solver directly, we
do not need tryToReplaceWithConstantRange afterwards anymore.
Reviewers: dberlin, mssimpso, davide, efriedma
Reviewed By: mssimpso
Differential Revision: https://reviews.llvm.org/D43762
llvm-svn: 328307
Loop peeling also has an impact on the induction variables, so we should
benefit from induction variable simplification after peeling too.
Reviewers: sanjoy, bogner, mzolotukhin, efriedma
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D43878
llvm-svn: 328301
Transforms/Scalar/SCCP.cpp implemented both the Scalar and IPO SCCP, but
this meant Transforms/Scalar including Transfroms/IPO headers, creating
a circular dependency. (IPO depends on Scalar already) - so move the IPO
SCCP shims out into IPO and the basic library implementation accessible
from Scalar/SCCP.h to be used from the IPO/SCCP.cpp implementation.
llvm-svn: 328250
Summary:
When building with libFuzzer, converting control flow to selects or
obscuring the original operands of CMPs reduces the effectiveness of
libFuzzer's heuristics.
This patch provides an attribute to disable or modify certain optimizations
for optimal fuzzing signal.
Provides a less aggressive alternative to https://reviews.llvm.org/D44057.
Reviewers: vitalybuka, davide, arsenm, hfinkel
Reviewed By: vitalybuka
Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc
Differential Revision: https://reviews.llvm.org/D44232
llvm-svn: 328214
Summary:
LoopPredication is not profitable when the loop is known to always exit
through some block other than the latch block.
A coarse grained latch check can cause loop predication to predicate the
loop, and unconditionally deoptimize.
However, without predicating the loop, the guard may never fail within the
loop during the dynamic execution because the non-latch loop termination
condition exits the loop before the latch condition causes the loop to
exit.
We teach LP about this using BranchProfileInfo pass.
Reviewers: apilipenko, skatkov, mkazantsev, reames
Reviewed by: skatkov
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44667
llvm-svn: 328210
The dominator tree analysis can be preserved easily.
Some other kinds of analysis can probably be preserved
too.
Reviewers: junbuml, dberlin
Reviewed By: dberlin
Differential Revision: https://reviews.llvm.org/D43173
llvm-svn: 328206
DuplicateInstructionsInSplitBetween can preserve the DT by passing
through DT to SplitEdge.
Reviewers: sanjoy, junbuml, anna, kuhar
Reviewed By: kuhar
Differential Revision: https://reviews.llvm.org/D44629
llvm-svn: 328189
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
llvm-svn: 328165
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
MemCpyOpt 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.
We also add a few tests to fill gaps in the testing of this pass.
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, rL324960, rL325816, rL327398, rL327421 )
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: 328097
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Backed out for causing performance regressions. Re-landing
because we've determined that these regressions were noise.
Original Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 328096
The inline assembly generated for the ARC autorelease elision marker
must have a funclet token if it's emitted inside a funclet, otherwise
the inline assembly (and all subsequent code in the funclet) will be
marked unreachable by WinEHPrepare.
Note that this only applies for the non-O0 case, since at O0, clang
emits the autorelease elision marker itself rather than deferring to the
backend. The fix for clang is handled in a separate change.
Differential Revision: https://reviews.llvm.org/D44641
llvm-svn: 328042