[llvm] [SLP]Model reduction_add(ext(<n x i1>)) as ext(ctpop(bitcast <n x i1> to int n)) (PR #116875)
Alexey Bataev via llvm-commits
llvm-commits at lists.llvm.org
Tue Nov 19 13:26:40 PST 2024
https://github.com/alexey-bataev updated https://github.com/llvm/llvm-project/pull/116875
>From 75a6cd459d9bac4266d7cdb8764fd08cbaef5d5c Mon Sep 17 00:00:00 2001
From: Alexey Bataev <a.bataev at outlook.com>
Date: Tue, 19 Nov 2024 20:54:10 +0000
Subject: [PATCH] =?UTF-8?q?[=F0=9D=98=80=F0=9D=97=BD=F0=9D=97=BF]=20initia?=
=?UTF-8?q?l=20version?=
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Created using spr 1.3.5
---
.../Transforms/Vectorize/SLPVectorizer.cpp | 107 +++++++++++++-----
.../X86/alternate-cmp-swapped-pred.ll | 5 +-
.../zext-incoming-for-neg-icmp.ll | 5 +-
3 files changed, 86 insertions(+), 31 deletions(-)
diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index e70627b6afc10d..fe5099d68024c3 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -1371,6 +1371,18 @@ class BoUpSLP {
return MinBWs.at(VectorizableTree.front().get()).second;
}
+ /// Returns reduction bitwidth and signedness, if it does not match the
+ /// original requested size.
+ std::optional<std::pair<unsigned, bool>> getReductionBitWidthAndSign() const {
+ if (ReductionBitWidth == 0 ||
+ ReductionBitWidth ==
+ DL->getTypeSizeInBits(
+ VectorizableTree.front()->Scalars.front()->getType()))
+ return std::nullopt;
+ return std::make_pair(ReductionBitWidth,
+ MinBWs.at(VectorizableTree.front().get()).second);
+ }
+
/// Builds external uses of the vectorized scalars, i.e. the list of
/// vectorized scalars to be extracted, their lanes and their scalar users. \p
/// ExternallyUsedValues contains additional list of external uses to handle
@@ -17885,24 +17897,37 @@ void BoUpSLP::computeMinimumValueSizes() {
// Add reduction ops sizes, if any.
if (UserIgnoreList &&
isa<IntegerType>(VectorizableTree.front()->Scalars.front()->getType())) {
- for (Value *V : *UserIgnoreList) {
- auto NumSignBits = ComputeNumSignBits(V, *DL, 0, AC, nullptr, DT);
- auto NumTypeBits = DL->getTypeSizeInBits(V->getType());
- unsigned BitWidth1 = NumTypeBits - NumSignBits;
- if (!isKnownNonNegative(V, SimplifyQuery(*DL)))
- ++BitWidth1;
- unsigned BitWidth2 = BitWidth1;
- if (!RecurrenceDescriptor::isIntMinMaxRecurrenceKind(::getRdxKind(V))) {
- auto Mask = DB->getDemandedBits(cast<Instruction>(V));
- BitWidth2 = Mask.getBitWidth() - Mask.countl_zero();
+ // Convert vector_reduce_add(ZExt(<n x i1>)) to
+ // ZExtOrTrunc(ctpop(bitcast <n x i1> to in)).
+ if (all_of(*UserIgnoreList,
+ [](Value *V) {
+ return cast<Instruction>(V)->getOpcode() == Instruction::Add;
+ }) &&
+ VectorizableTree.front()->State == TreeEntry::Vectorize &&
+ VectorizableTree.front()->getOpcode() == Instruction::ZExt &&
+ cast<CastInst>(VectorizableTree.front()->getMainOp())->getSrcTy() ==
+ Builder.getInt1Ty()) {
+ ReductionBitWidth = 1;
+ } else {
+ for (Value *V : *UserIgnoreList) {
+ auto NumSignBits = ComputeNumSignBits(V, *DL, 0, AC, nullptr, DT);
+ auto NumTypeBits = DL->getTypeSizeInBits(V->getType());
+ unsigned BitWidth1 = NumTypeBits - NumSignBits;
+ if (!isKnownNonNegative(V, SimplifyQuery(*DL)))
+ ++BitWidth1;
+ unsigned BitWidth2 = BitWidth1;
+ if (!RecurrenceDescriptor::isIntMinMaxRecurrenceKind(::getRdxKind(V))) {
+ auto Mask = DB->getDemandedBits(cast<Instruction>(V));
+ BitWidth2 = Mask.getBitWidth() - Mask.countl_zero();
+ }
+ ReductionBitWidth =
+ std::max(std::min(BitWidth1, BitWidth2), ReductionBitWidth);
}
- ReductionBitWidth =
- std::max(std::min(BitWidth1, BitWidth2), ReductionBitWidth);
- }
- if (ReductionBitWidth < 8 && ReductionBitWidth > 1)
- ReductionBitWidth = 8;
+ if (ReductionBitWidth < 8 && ReductionBitWidth > 1)
+ ReductionBitWidth = 8;
- ReductionBitWidth = bit_ceil(ReductionBitWidth);
+ ReductionBitWidth = bit_ceil(ReductionBitWidth);
+ }
}
bool IsTopRoot = NodeIdx == 0;
while (NodeIdx < VectorizableTree.size() &&
@@ -19758,8 +19783,8 @@ class HorizontalReduction {
// Estimate cost.
InstructionCost TreeCost = V.getTreeCost(VL);
- InstructionCost ReductionCost =
- getReductionCost(TTI, VL, IsCmpSelMinMax, ReduxWidth, RdxFMF);
+ InstructionCost ReductionCost = getReductionCost(
+ TTI, VL, IsCmpSelMinMax, RdxFMF, V.getReductionBitWidthAndSign());
InstructionCost Cost = TreeCost + ReductionCost;
LLVM_DEBUG(dbgs() << "SLP: Found cost = " << Cost
<< " for reduction\n");
@@ -19864,10 +19889,12 @@ class HorizontalReduction {
createStrideMask(I, ScalarTyNumElements, VL.size());
Value *Lane = Builder.CreateShuffleVector(VectorizedRoot, Mask);
ReducedSubTree = Builder.CreateInsertElement(
- ReducedSubTree, emitReduction(Lane, Builder, TTI), I);
+ ReducedSubTree,
+ emitReduction(Lane, Builder, TTI, RdxRootInst->getType()), I);
}
} else {
- ReducedSubTree = emitReduction(VectorizedRoot, Builder, TTI);
+ ReducedSubTree = emitReduction(VectorizedRoot, Builder, TTI,
+ RdxRootInst->getType());
}
if (ReducedSubTree->getType() != VL.front()->getType()) {
assert(ReducedSubTree->getType() != VL.front()->getType() &&
@@ -20048,12 +20075,13 @@ class HorizontalReduction {
private:
/// Calculate the cost of a reduction.
- InstructionCost getReductionCost(TargetTransformInfo *TTI,
- ArrayRef<Value *> ReducedVals,
- bool IsCmpSelMinMax, unsigned ReduxWidth,
- FastMathFlags FMF) {
+ InstructionCost getReductionCost(
+ TargetTransformInfo *TTI, ArrayRef<Value *> ReducedVals,
+ bool IsCmpSelMinMax, FastMathFlags FMF,
+ const std::optional<std::pair<unsigned, bool>> BitwidthAndSign) {
TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput;
Type *ScalarTy = ReducedVals.front()->getType();
+ unsigned ReduxWidth = ReducedVals.size();
FixedVectorType *VectorTy = getWidenedType(ScalarTy, ReduxWidth);
InstructionCost VectorCost = 0, ScalarCost;
// If all of the reduced values are constant, the vector cost is 0, since
@@ -20112,8 +20140,22 @@ class HorizontalReduction {
VecTy, APInt::getAllOnes(ScalarTyNumElements), /*Insert*/ true,
/*Extract*/ false, TTI::TCK_RecipThroughput);
} else {
- VectorCost = TTI->getArithmeticReductionCost(RdxOpcode, VectorTy, FMF,
- CostKind);
+ auto [Bitwidth, IsSigned] =
+ BitwidthAndSign.value_or(std::make_pair(0u, false));
+ if (RdxKind == RecurKind::Add && Bitwidth == 1) {
+ // Represent vector_reduce_add(ZExt(<n x i1>)) to
+ // ZExtOrTrunc(ctpop(bitcast <n x i1> to in)).
+ auto *IntTy = IntegerType::get(ScalarTy->getContext(), ReduxWidth);
+ IntrinsicCostAttributes ICA(Intrinsic::ctpop, IntTy, {IntTy}, FMF);
+ VectorCost =
+ TTI->getCastInstrCost(Instruction::BitCast, IntTy,
+ getWidenedType(ScalarTy, ReduxWidth),
+ TTI::CastContextHint::None, CostKind) +
+ TTI->getIntrinsicInstrCost(ICA, CostKind);
+ } else {
+ VectorCost = TTI->getArithmeticReductionCost(RdxOpcode, VectorTy,
+ FMF, CostKind);
+ }
}
}
ScalarCost = EvaluateScalarCost([&]() {
@@ -20150,11 +20192,22 @@ class HorizontalReduction {
/// Emit a horizontal reduction of the vectorized value.
Value *emitReduction(Value *VectorizedValue, IRBuilderBase &Builder,
- const TargetTransformInfo *TTI) {
+ const TargetTransformInfo *TTI, Type *DestTy) {
assert(VectorizedValue && "Need to have a vectorized tree node");
assert(RdxKind != RecurKind::FMulAdd &&
"A call to the llvm.fmuladd intrinsic is not handled yet");
+ auto *FTy = cast<FixedVectorType>(VectorizedValue->getType());
+ if (FTy->getScalarType() == Builder.getInt1Ty() &&
+ RdxKind == RecurKind::Add &&
+ DestTy->getScalarType() != FTy->getScalarType()) {
+ // Convert vector_reduce_add(ZExt(<n x i1>)) to
+ // ZExtOrTrunc(ctpop(bitcast <n x i1> to in)).
+ Value *V = Builder.CreateBitCast(
+ VectorizedValue, Builder.getIntNTy(FTy->getNumElements()));
+ ++NumVectorInstructions;
+ return Builder.CreateUnaryIntrinsic(Intrinsic::ctpop, V);
+ }
++NumVectorInstructions;
return createSimpleReduction(Builder, VectorizedValue, RdxKind);
}
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/alternate-cmp-swapped-pred.ll b/llvm/test/Transforms/SLPVectorizer/X86/alternate-cmp-swapped-pred.ll
index ecf85159efdfbd..f00b846bf4f5bd 100644
--- a/llvm/test/Transforms/SLPVectorizer/X86/alternate-cmp-swapped-pred.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/alternate-cmp-swapped-pred.ll
@@ -11,8 +11,9 @@ define i16 @test(i16 %call37) {
; CHECK-NEXT: [[TMP2:%.*]] = icmp slt <8 x i16> [[SHUFFLE]], zeroinitializer
; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt <8 x i16> [[SHUFFLE]], zeroinitializer
; CHECK-NEXT: [[TMP4:%.*]] = shufflevector <8 x i1> [[TMP2]], <8 x i1> [[TMP3]], <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 12, i32 5, i32 6, i32 7>
-; CHECK-NEXT: [[TMP5:%.*]] = zext <8 x i1> [[TMP4]] to <8 x i16>
-; CHECK-NEXT: [[TMP6:%.*]] = call i16 @llvm.vector.reduce.add.v8i16(<8 x i16> [[TMP5]])
+; CHECK-NEXT: [[TMP8:%.*]] = bitcast <8 x i1> [[TMP4]] to i8
+; CHECK-NEXT: [[TMP7:%.*]] = call i8 @llvm.ctpop.i8(i8 [[TMP8]])
+; CHECK-NEXT: [[TMP6:%.*]] = zext i8 [[TMP7]] to i16
; CHECK-NEXT: [[OP_RDX:%.*]] = add i16 [[TMP6]], 0
; CHECK-NEXT: ret i16 [[OP_RDX]]
;
diff --git a/llvm/test/Transforms/SLPVectorizer/zext-incoming-for-neg-icmp.ll b/llvm/test/Transforms/SLPVectorizer/zext-incoming-for-neg-icmp.ll
index 89fcc7e983749b..303e31dfa5e64a 100644
--- a/llvm/test/Transforms/SLPVectorizer/zext-incoming-for-neg-icmp.ll
+++ b/llvm/test/Transforms/SLPVectorizer/zext-incoming-for-neg-icmp.ll
@@ -14,8 +14,9 @@ define i32 @test(i32 %a, i8 %b, i8 %c) {
; CHECK-NEXT: [[TMP8:%.*]] = zext <4 x i8> [[TMP2]] to <4 x i16>
; CHECK-NEXT: [[TMP9:%.*]] = sext <4 x i8> [[TMP4]] to <4 x i16>
; CHECK-NEXT: [[TMP5:%.*]] = icmp sle <4 x i16> [[TMP8]], [[TMP9]]
-; CHECK-NEXT: [[TMP6:%.*]] = zext <4 x i1> [[TMP5]] to <4 x i32>
-; CHECK-NEXT: [[TMP7:%.*]] = call i32 @llvm.vector.reduce.add.v4i32(<4 x i32> [[TMP6]])
+; CHECK-NEXT: [[TMP10:%.*]] = bitcast <4 x i1> [[TMP5]] to i4
+; CHECK-NEXT: [[TMP11:%.*]] = call i4 @llvm.ctpop.i4(i4 [[TMP10]])
+; CHECK-NEXT: [[TMP7:%.*]] = zext i4 [[TMP11]] to i32
; CHECK-NEXT: [[OP_RDX:%.*]] = add i32 [[TMP7]], [[A]]
; CHECK-NEXT: ret i32 [[OP_RDX]]
;
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