5412 Commits

Author SHA1 Message Date
Sam Tebbs
795e35a653
Reland "[LoopVectorizer] Add support for partial reductions" with non-phi operand fix. (#121744)
This relands the reverted #120721 with a fix for cases where neither
reduction operand are the reduction phi. Only
63114239cc8d26225a0ef9920baacfc7cc00fc58 and
63114239cc8d26225a0ef9920baacfc7cc00fc58 are new on top of the reverted
PR.

---------

Co-authored-by: Nicholas Guy <nicholas.guy@arm.com>
2025-01-13 11:20:35 +00:00
Mel Chen
56a37a3c76
[SLPVectorizer] Refactor HorizontalReduction::createOp (NFC) (#121549)
This patch simplifies select-based integer min/max reductions by
utilizing `llvm::getMinMaxReductionPredicate`, and generates
intrinsic-based min/max reductions by utilizing
`llvm::getMinMaxReductionIntrinsicOp`.
2025-01-13 16:11:31 +08:00
Florian Hahn
8df64ed777 [LV] Don't consider IV increments uniform if exit value is used outside.
In some cases, there might be a chain of uniform instructions producing
the exit value. To generate correct code in all cases, consider the IV
increment not uniform, if there are users outside the loop.

Instead, let VPlan narrow the IV, if possible using the logic from
3ff1d01985752.

Test case from #122602 verified with Alive2:
    https://alive2.llvm.org/ce/z/bA4EGj

Fixes https://github.com/llvm/llvm-project/issues/122496.
Fixes https://github.com/llvm/llvm-project/issues/122602.
2025-01-12 22:03:21 +00:00
Florian Hahn
3ff1d01985 Recommit "[VPlan] Try to narrow wide and replicating recipes to uniform recipes."
This reverts commit 0ebb3ac7c92c4c1c44e7f3d17832d75ec5a42a67.

Re-applies commit with typos fixed.
2025-01-12 20:10:28 +00:00
Florian Hahn
0ebb3ac7c9 Revert "[VPlan] Try to narrow wide and replicating recipes to uniform recipes."
This reverts commit 1afba19913253dda865a8e57b37b9f4dabead1ac.

Typo breaking the build
2025-01-12 19:37:45 +00:00
Florian Hahn
1afba19913 [VPlan] Try to narrow wide and replicating recipes to uniform recipes.
Use the existing VPlan-based analysis to identify recipes that only have
their first lane demanded and transform them to uniform recpliate
recipes. This simplifies the generated code in some places and prepares
for fixing https://github.com/llvm/llvm-project/issues/122496.
2025-01-12 19:32:01 +00:00
Florian Hahn
7f59b4e998
[VPlan] Skip non-induction phi recipes in legalizeAndOptimizeInductions.
The body of the loop only applies to wide induction recipes, skip any other
header phi recipes up-frond
2025-01-11 20:33:02 +00:00
Vasileios Porpodas
25b90c4ef6 [SandboxVec][SeedCollector][NFC] Remove redundant 'else' and move the assertion within the 'if' 2025-01-10 14:54:44 -08:00
vporpo
9248428db7
[SandboxVec][DAG][NFC] Refactor setNextNode() and setPrevNode() (#122363)
This patch updates DAG's `setNextNode()` and `setPrevNode()` to update
both nodes of the link.
2025-01-10 13:32:33 -08:00
Han-Kuan Chen
35e76b6a4f Revert "[SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (#120198)"
This reverts commit f3d6cdc5aebafac3961d4fccbd2ca0e302c6082c.
2025-01-10 10:09:54 -08:00
Alexey Bataev
681c83a2f9 [SLP]Fix mask generation after cost estimation
When estimating the cost of entries shuffles for buildvectors, need to
rebuild original mask, not a generated submask, used for subregisters
analysis.

Fixes #122430
2025-01-10 09:32:35 -08:00
Alex MacLean
986f2ac48f
[SLPVectorizer] minor tweaks around lambdas for compatibility with older compilers (#122348)
Older version of msvc do not have great lambda support and are not able
to handle uses of class data or lambdas with implicit return types in
some cases. These minor changes improve the sources compatibility with
older msvc and don't hurt readability either.
2025-01-10 09:18:28 -08:00
Alexey Bataev
3c9c94a24f Revert "[SLP]Fix mask generation after cost estimation"
This reverts commit 547ba9730bf05df3383150f730a689f2c8336206 to fix
buildbots reported in
https://lab.llvm.org/buildbot/#/builders/123/builds/11370, https://lab.llvm.org/buildbot/#/builders/133/builds/9492
2025-01-10 08:46:42 -08:00
Alexey Bataev
547ba9730b [SLP]Fix mask generation after cost estimation
When estimating the cost of entries shuffles for buildvectors, need to
rebuild original mask, not a generated submask, used for subregisters
analysis.

Fixes #122430
2025-01-10 08:17:56 -08:00
Mel Chen
e0f14e11c7
[SLPVectorizer] Refine the scope of RdxOpcode in HorizontalReduction::createOp (NFC) (#122239)
This patch is one part of unifying IAnyOf and FAnyOf reduction. #118393
The related patch is #118777.
2025-01-10 16:01:36 +08:00
Han-Kuan Chen
f3d6cdc5ae [SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (#120198)
Add TreeEntry::hasState.
Add assert for getTreeEntry.
Remove the OpValue parameter from the canReuseExtract function.
Remove the Opcode parameter from the ComputeMaxBitWidth lambda function.
2025-01-09 23:41:52 -08:00
Han-Kuan Chen
5454ac28b3 Revert "[SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (#120198)"
This reverts commit 760f550de25792db83cd39c88ef57ab6d80a41a0.
2025-01-09 18:41:47 -08:00
Han-Kuan Chen
36b423e0f8
[SLP] NFC. Refactor getSameOpcode and reduce for loop iterations. (#122241)
Replace Cnt and AltIndex with MainOp and AltOp.
Reduce the number of iterations in the for loop.
2025-01-10 09:06:07 +08:00
Han-Kuan Chen
760f550de2
[SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (#120198)
Add TreeEntry::hasState.
Add assert for getTreeEntry.
Remove the OpValue parameter from the canReuseExtract function.
Remove the Opcode parameter from the ComputeMaxBitWidth lambda function.
2025-01-10 09:05:39 +08:00
Florian Hahn
7ffb691595
[VPlan] Remove dead ToRemove (NFC). 2025-01-09 22:02:32 +00:00
vporpo
6312beef78
[SandboxVec][BottomUpVec] Use SeedCollector and slice seeds (#120826)
With this patch we switch from the temporary dummy seeds to actual seeds
provided by the seed collector.
The seeds get sliced and each slice is used as the starting point for
vectorization.
2025-01-09 11:53:48 -08:00
Alexey Bataev
5ff36748cf [SLP]Fix mask processing for reused gathered scalars
Need to sync the mask between cost and actual emission to avoid bugs in
mask calculation

Fixes #122324
2025-01-09 11:24:48 -08:00
Florian Hahn
b0697dc1de
[LV] Only check isVectorizableEarlyExitLoop with multiple exits. (#121994)
Currently we emit early-exit related debug messages/remarks even when
there is a single exit. Update to only check isVectorizableEarlyExitLoop
if there isn't a single exit block.

PR: https://github.com/llvm/llvm-project/pull/121994
2025-01-09 12:05:19 +00:00
Benjamin Maxwell
f88ef1bd1b
[LV] Teach LoopVectorizationLegality about struct vector calls (#119221)
This is a split-off from #109833 and only adds code relating to checking
if a struct-returning call can be vectorized.

This initial patch only allows the case where all users of the struct
return are `extractvalue` operations that can be widened.

```
%call = tail call { float, float } @foo(float %in_val)
%extract_a = extractvalue { float, float } %call, 0
%extract_b = extractvalue { float, float } %call, 1
```

Note: The tests require the VFABI changes from #119000 to pass.
2025-01-09 09:27:29 +00:00
Alexey Bataev
5b76a2e51b [SLP]Correctly calculate mask for the inserted vector 2025-01-08 15:18:06 -08:00
Alexey Bataev
0d921f96d4 [SLP][NFC]Introduce and use createInsertVector helper function, NFC 2025-01-08 14:26:13 -08:00
David Green
676c641718
[VectorCombine] Use getInstructionCost to cost Shuffle. (#122068)
This allows it to produce a more accurate cost for the shuffle, using
the more accurate calls to getShuffleCost in getInstructionCost. It
helps fix some of the regressions from vector combine a little while
ago, now that we have better subvector extract costs.
2025-01-08 20:48:40 +00:00
Alexey Bataev
1160994602 [SLP]Fix a crash for very long GEP chains
Need to check if the GEP bases are equal and return false early. Also,
need to return false if the lookup is too deep, considering bases equal
too. Fixes a crash in the assertion.
2025-01-08 06:47:41 -08:00
Luke Lau
f0d5104c94
[VPlan] Handle some VPInstructions in may{Read,Write}FromMemory (#120058)
This just copies the same conservative definition from mayWriteToMemory,
and enables more VPInstructions to be hoisted out in LICM.

I think this should give more accurate costs, and I was able to build
llvm-test-suite without the legacy-vplan cost model assertion going off.
2025-01-08 15:17:26 +08:00
Vyacheslav Klochkov
9184c42869
[LoadStoreVectorizer] Postprocess and merge equivalence classes (#121861)
This patch introduces a new method:

void Vectorizer::mergeEquivalenceClasses(EquivalenceClassMap &EQClasses)
const;

The method is called at the end of
Vectorizer::collectEquivalenceClasses() and is needed to merge
equivalence classes that differ only by their underlying objects (UO1
and UO2), where UO1 is 1-level-indirection underlying base for UO2. This
situation arises due to the limited lookup depth used during the search
of underlying bases with llvm::getUnderlyingObject(ptr).

Using any fixed lookup depth can result into creation of multiple
equivalence classes that only differ by 1-level indirection bases.

The new approach merges equivalence classes if they have adjacent bases
(1-level indirection). If a series of equivalence classes form ladder
formed of 1-step/level indirections, they are all merged into a single
equivalence class. This provides more opportunities for the load-store
vectorizer to generate better vectors.

---------

Signed-off-by: Klochkov, Vyacheslav N <vyacheslav.n.klochkov@intel.com>
2025-01-07 17:17:26 -08:00
Florian Hahn
0eaa69eb23
[VPlan] Handle VPExpandSCEVRecipe in isUniformAfterVectorization.
VPExpandSCEVRecipes must be placed in the entry and are alway uniform.
This fixes a crash by always identifying them as uniform, even if the
main vector loop region has been removed.

Fixes https://github.com/llvm/llvm-project/issues/121897.
2025-01-07 21:35:09 +00:00
Florian Mayer
ef391dbc29
[LV] Drop incorrect inbounds for reverse vector pointer when folding tail (#120730)
When folding the tail, we may compute an address that we don't in the
original scalar loop and it may not be inbounds. Drop Inbounds in that
case.
2025-01-07 06:14:01 -08:00
Simon Pilgrim
a5e129ccde [CostModel][X86] getVectorInstrCost - correctly cost v4f32 insertelement into index 0
This is just the MOVSS instruction (SSE41 INSERTPS is still necessary for index != 0)

This exposed an issue in VectorCombine::foldInsExtFNeg - we need to use the more general SK_PermuteTwoSrc shuffle kind to allow getShuffleCost to match other shuffle kinds (not just SK_Select).
2025-01-07 12:23:45 +00:00
Florian Hahn
f9369cc602
[VPlan] Make sure last IV increment value is available if needed.
Legalize extract-from-ends using uniform VPReplicateRecipe of wide
inductions to use regular VPReplicateRecipe, so the correct end value
is available.

Fixes https://github.com/llvm/llvm-project/issues/121745.
2025-01-06 22:40:41 +00:00
Simon Pilgrim
d993b11b86 [VectorCombine] Remove superfluous whitespace from debug log comment. NFC. 2025-01-06 15:37:15 +00:00
David Sherwood
1feeeb47e5
[LoopVectorize][NFC] Move "LV: Selecting VF" debug output (#120744)
Move the debug output that prints out the selected VF from
selectVectorizationFactor -> computeBestVF. This means that the output
will still be written even after removing the assert for the legacy and
vplan cost models matching.
2025-01-06 10:39:34 +00:00
Yingwei Zheng
a77346bad0
[IRBuilder] Refactor FMF interface (#121657)
Up to now, the only way to set specified FMF flags in IRBuilder is to
use `FastMathFlagGuard`. It makes the code ugly and hard to maintain.

This patch introduces a helper class `FMFSource` to replace the original
parameter `Instruction *FMFSource` in IRBuilder. To maximize the
compatibility, it accepts an instruction or a specified FMF.
This patch also removes the use of `FastMathFlagGuard` in some simple
cases.

Compile-time impact:
https://llvm-compile-time-tracker.com/compare.php?from=f87a9db8322643ccbc324e317a75b55903129b55&to=9397e712f6010be15ccf62f12740e9b4a67de2f4&stat=instructions%3Au
2025-01-06 14:37:04 +08:00
Florian Hahn
f4230b4332
[VPlan] Add and use debug location for VPScalarCastRecipe.
Update the recipe it always take a debug location and set it.
2025-01-05 20:08:51 +00:00
Florian Hahn
f48884ded8
[VPlan] Remove loop region in optimizeForVFAndUF. (#108378)
Update optimizeForVFAndUF to completely remove the vector loop region
when possible. At the moment, we cannot remove the region if it contains

* widened IVs: the recipe is needed to generate the step vector
* reductions: ComputeReductionResults requires the reduction phi recipe
for codegen.

Both cases can be addressed by more explicit modeling.

The patch also includes a number of updates to allow executing VPlans
without a vector loop region.

Depends on https://github.com/llvm/llvm-project/pull/110004
2025-01-05 15:50:42 +00:00
Simon Pilgrim
054e7c5971 [VectorCombine] foldInsExtVectorToShuffle - ignore shuffle costs for 'identity' insertion masks
<u,1,u,u> 'inplace' single src shuffles can be treated as free identity shuffles - ignore any shuffle cost (similar to what we already do in other folds like foldShuffleOfShuffles) - eventually getShuffleCost should just return TCC_Free in these cases but in a lot of the targets' shuffle cost logic this currently ends up treated as a generic SK_PermuteSingleSrc.

We still want to generate the shuffle as it will help further shuffle folds with the additional PoisonMaskElem 'undemanded' elements.
2025-01-05 13:02:31 +00:00
Florian Hahn
df4a615c98
[VPlan] Convert induction increment check to be VPlan-based.
Check the VPlan directly to determine if a VPValue is an optimiziable IV
or IV use instead of checking the underlying IR instructions.

Split off from https://github.com/llvm/llvm-project/pull/112147. This
refactoring enables moving IV end value creation from the legacy
fixupIVUsers to a VPlan-based transform.

There is one case we now won't optimize, that is IVs with subtracts and
non-constant steps. But as this is a minor optimization and doesn't
impact correctness, the benefits of performing the check in VPlan should
outweigh the missed case.
2025-01-05 11:16:01 +00:00
Luke Lau
7700695739
[VPlan] Fix crash with EVL tail folding intrinsic with no corresponding VP (#121542)
This fixes a crash when building SPEC CPU 2017 with EVL tail folding
when widening @llvm.log10 intrinsics.

@llvm.log10 and some other intrinsics don't have a corresponding VP
intrinsic, so this fixes the crash by removing the assert and bailing
instead.
2025-01-05 11:41:56 +08:00
Florian Hahn
b95cce9904
[VPlan] Update wide induction inc recipes to use same step as Wide IV.
Update wide induction increments to use the same step as the corresponding
wide induction. This enables detecting induction increments directly in
VPlan and removes redundant splats.
2025-01-04 20:04:59 +00:00
Florian Hahn
20d491bb99
[VPlan] Remove re-using vector PH in VPBasicBlock::execute (NFC).
Remove logic to re-use the previous basic block for the vector pre
header from VPBasicBlock::execute. The preheader is now modeled as
VPIRBasicBlock, so the code is no longer needed.

Split off from https://github.com/llvm/llvm-project/pull/108378.
2025-01-03 19:56:44 +00:00
Florian Hahn
11c6af666b
[VPlan] Fix name ExitVPBB -> MiddleVPBB (NFC).
ExitVPBB actually refers to the middle block, clarify name.
2025-01-03 19:28:03 +00:00
Han-Kuan Chen
c50370c67a
[SLP] NFC. Use InstructionsState::valid if users just want to know whether VL has same opcode. (#120217)
Add assert for InstructionsState::getOpcode.
Use InstructionsState::getOpcode only when necessary.
2025-01-04 00:44:57 +08:00
Simon Pilgrim
e3ec5a7286
[VectorCombine] foldShuffleOfBinops - fold shuffle(binop(shuffle(x),shuffle(z)),binop(shuffle(y),shuffle(w)) -> binop(shuffle(x,z),shuffle(y,w)) (#120984)
Some patterns (in particular horizontal style patterns) can end up with shuffles straddling both sides of a binop/cmp.

Where individually the folds aren't worth it, by merging the (oneuse) shuffles we can notably reduce the net instruction count and cost.

One of the final steps towards finally addressing #34072
2025-01-03 10:29:07 +00:00
Florian Hahn
5f5792aedb
[VPlan] Use removeDeadRecipes in optimizeForVFAndUF (NFCI)
Split off from https://github.com/llvm/llvm-project/pull/108378.
2025-01-02 20:10:46 +00:00
Simon Pilgrim
035e64c0ec [VectorCombine] eraseInstruction - ensure we reattempt to fold other users of an erased instruction's operands (REAPPLIED)
As we're reducing the use count of the operands its more likely that they will now fold, as they were previously being prevented by a m_OneUse check, or the cost of retaining the extra instruction had been too high.

This is necessary for some upcoming patches, although the only change so far is instruction ordering as it allows some SSE folds of 256/512-bit with 128-bit subvectors to occur earlier in foldShuffleToIdentity as the subvector concats are free.

Reapplied with a fix for foldSingleElementStore/scalarizeLoadExtract which were replacing/removing memory operations - we need to ensure that the worklist is populated in the correct order so all users of the old memory operations are erased first, so there are no remaining users of the loads when its time to remove them as well.

Pulled out of #120984
2025-01-02 18:19:02 +00:00
Simon Pilgrim
f739aa4004 [VectorCombine] replaceValue - add "VC: Replacing" debug message to help the log show replacement for old/new. 2025-01-02 17:23:13 +00:00