[SLP]Initial support for non-power-of-2 (but still whole register) number of elements in operands.

Patch adds basic support for non-power-of-2 number of elements in
operands. The patch still requires that this number addresses whole
registers.

Reviewers: RKSimon, preames

Reviewed By: preames

Pull Request: https://github.com/llvm/llvm-project/pull/107273
This commit is contained in:
Alexey Bataev
2024-09-25 10:43:27 -04:00
parent fea159671a
commit 1bfca99909
3 changed files with 108 additions and 39 deletions

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@@ -2538,7 +2538,19 @@ public:
unsigned getNumberOfParts(Type *Tp) {
std::pair<InstructionCost, MVT> LT = getTypeLegalizationCost(Tp);
return LT.first.isValid() ? *LT.first.getValue() : 0;
if (!LT.first.isValid())
return 0;
// Try to find actual number of parts for non-power-of-2 elements as
// ceil(num-of-elements/num-of-subtype-elements).
if (auto *FTp = dyn_cast<FixedVectorType>(Tp);
Tp && LT.second.isFixedLengthVector() &&
!has_single_bit(FTp->getNumElements())) {
if (auto *SubTp = dyn_cast_if_present<FixedVectorType>(
EVT(LT.second).getTypeForEVT(Tp->getContext()));
SubTp && SubTp->getElementType() == FTp->getElementType())
return divideCeil(FTp->getNumElements(), SubTp->getNumElements());
}
return *LT.first.getValue();
}
InstructionCost getAddressComputationCost(Type *Ty, ScalarEvolution *,

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@@ -260,6 +260,20 @@ static FixedVectorType *getWidenedType(Type *ScalarTy, unsigned VF) {
VF * getNumElements(ScalarTy));
}
/// Returns the number of elements of the given type \p Ty, not less than \p Sz,
/// which forms type, which splits by \p TTI into whole vector types during
/// legalization.
static unsigned getFullVectorNumberOfElements(const TargetTransformInfo &TTI,
Type *Ty, unsigned Sz) {
if (!isValidElementType(Ty))
return bit_ceil(Sz);
// Find the number of elements, which forms full vectors.
const unsigned NumParts = TTI.getNumberOfParts(getWidenedType(Ty, Sz));
if (NumParts == 0 || NumParts >= Sz)
return bit_ceil(Sz);
return bit_ceil(divideCeil(Sz, NumParts)) * NumParts;
}
static void transformScalarShuffleIndiciesToVector(unsigned VecTyNumElements,
SmallVectorImpl<int> &Mask) {
// The ShuffleBuilder implementation use shufflevector to splat an "element".
@@ -394,7 +408,7 @@ static bool isVectorLikeInstWithConstOps(Value *V) {
/// total number of elements \p Size and number of registers (parts) \p
/// NumParts.
static unsigned getPartNumElems(unsigned Size, unsigned NumParts) {
return PowerOf2Ceil(divideCeil(Size, NumParts));
return std::min<unsigned>(Size, bit_ceil(divideCeil(Size, NumParts)));
}
/// Returns correct remaining number of elements, considering total amount \p
@@ -1222,6 +1236,22 @@ static bool doesNotNeedToSchedule(ArrayRef<Value *> VL) {
(all_of(VL, isUsedOutsideBlock) || all_of(VL, areAllOperandsNonInsts));
}
/// Returns true if widened type of \p Ty elements with size \p Sz represents
/// full vector type, i.e. adding extra element results in extra parts upon type
/// legalization.
static bool hasFullVectorsOrPowerOf2(const TargetTransformInfo &TTI, Type *Ty,
unsigned Sz) {
if (Sz <= 1)
return false;
if (!isValidElementType(Ty) && !isa<FixedVectorType>(Ty))
return false;
if (has_single_bit(Sz))
return true;
const unsigned NumParts = TTI.getNumberOfParts(getWidenedType(Ty, Sz));
return NumParts > 0 && NumParts < Sz && has_single_bit(Sz / NumParts) &&
Sz % NumParts == 0;
}
namespace slpvectorizer {
/// Bottom Up SLP Vectorizer.
@@ -3311,6 +3341,15 @@ private:
/// Return true if this is a non-power-of-2 node.
bool isNonPowOf2Vec() const {
bool IsNonPowerOf2 = !has_single_bit(Scalars.size());
return IsNonPowerOf2;
}
/// Return true if this is a node, which tries to vectorize number of
/// elements, forming whole vectors.
bool
hasNonWholeRegisterOrNonPowerOf2Vec(const TargetTransformInfo &TTI) const {
bool IsNonPowerOf2 = !hasFullVectorsOrPowerOf2(
TTI, getValueType(Scalars.front()), Scalars.size());
assert((!IsNonPowerOf2 || ReuseShuffleIndices.empty()) &&
"Reshuffling not supported with non-power-of-2 vectors yet.");
return IsNonPowerOf2;
@@ -3430,8 +3469,10 @@ private:
Last->State = EntryState;
// FIXME: Remove once support for ReuseShuffleIndices has been implemented
// for non-power-of-two vectors.
assert((has_single_bit(VL.size()) || ReuseShuffleIndices.empty()) &&
"Reshuffling scalars not yet supported for nodes with padding");
assert(
(hasFullVectorsOrPowerOf2(*TTI, getValueType(VL.front()), VL.size()) ||
ReuseShuffleIndices.empty()) &&
"Reshuffling scalars not yet supported for nodes with padding");
Last->ReuseShuffleIndices.append(ReuseShuffleIndices.begin(),
ReuseShuffleIndices.end());
if (ReorderIndices.empty()) {
@@ -4412,7 +4453,8 @@ BoUpSLP::findReusedOrderedScalars(const BoUpSLP::TreeEntry &TE) {
return std::nullopt;
auto *VecTy = getWidenedType(ScalarTy, NumScalars);
int NumParts = TTI->getNumberOfParts(VecTy);
if (NumParts == 0 || NumParts >= NumScalars)
if (NumParts == 0 || NumParts >= NumScalars ||
VecTy->getNumElements() % NumParts != 0)
NumParts = 1;
SmallVector<int> ExtractMask;
SmallVector<int> Mask;
@@ -5269,7 +5311,7 @@ BoUpSLP::getReorderingData(const TreeEntry &TE, bool TopToBottom) {
// node.
if (!TE.ReuseShuffleIndices.empty()) {
// FIXME: Support ReuseShuffleIndices for non-power-of-two vectors.
assert(!TE.isNonPowOf2Vec() &&
assert(!TE.hasNonWholeRegisterOrNonPowerOf2Vec(*TTI) &&
"Reshuffling scalars not yet supported for nodes with padding");
if (isSplat(TE.Scalars))
@@ -5509,7 +5551,7 @@ BoUpSLP::getReorderingData(const TreeEntry &TE, bool TopToBottom) {
}
// FIXME: Remove the non-power-of-two check once findReusedOrderedScalars
// has been auditted for correctness with non-power-of-two vectors.
if (!TE.isNonPowOf2Vec())
if (!TE.hasNonWholeRegisterOrNonPowerOf2Vec(*TTI))
if (std::optional<OrdersType> CurrentOrder = findReusedOrderedScalars(TE))
return CurrentOrder;
}
@@ -5662,8 +5704,8 @@ void BoUpSLP::reorderTopToBottom() {
});
// Reorder the graph nodes according to their vectorization factor.
for (unsigned VF = VectorizableTree.front()->getVectorFactor(); VF > 1;
VF = bit_ceil(VF) / 2) {
for (unsigned VF = VectorizableTree.front()->getVectorFactor();
!VFToOrderedEntries.empty() && VF > 1; VF -= 2 - (VF & 1U)) {
auto It = VFToOrderedEntries.find(VF);
if (It == VFToOrderedEntries.end())
continue;
@@ -5671,6 +5713,9 @@ void BoUpSLP::reorderTopToBottom() {
// used order and reorder scalar elements in the nodes according to this
// mostly used order.
ArrayRef<TreeEntry *> OrderedEntries = It->second.getArrayRef();
// Delete VF entry upon exit.
auto Cleanup = make_scope_exit([&]() { VFToOrderedEntries.erase(It); });
// All operands are reordered and used only in this node - propagate the
// most used order to the user node.
MapVector<OrdersType, unsigned,
@@ -6413,7 +6458,8 @@ static void gatherPossiblyVectorizableLoads(
if (NumScalars > 1) {
auto *VecTy = getWidenedType(ScalarTy, NumScalars);
NumParts = TTI.getNumberOfParts(VecTy);
if (NumParts == 0 || NumParts >= NumScalars)
if (NumParts == 0 || NumParts >= NumScalars ||
VecTy->getNumElements() % NumParts != 0)
NumParts = 1;
}
unsigned VF = PowerOf2Ceil(NumScalars / NumParts);
@@ -7529,25 +7575,26 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
UniqueValues.emplace_back(V);
}
size_t NumUniqueScalarValues = UniqueValues.size();
if (NumUniqueScalarValues == VL.size()) {
bool IsFullVectors = hasFullVectorsOrPowerOf2(
*TTI, UniqueValues.front()->getType(), NumUniqueScalarValues);
if (NumUniqueScalarValues == VL.size() &&
(VectorizeNonPowerOf2 || IsFullVectors)) {
ReuseShuffleIndices.clear();
} else {
// FIXME: Reshuffing scalars is not supported yet for non-power-of-2 ops.
if ((UserTreeIdx.UserTE && UserTreeIdx.UserTE->isNonPowOf2Vec()) ||
!llvm::has_single_bit(VL.size())) {
if ((UserTreeIdx.UserTE &&
UserTreeIdx.UserTE->hasNonWholeRegisterOrNonPowerOf2Vec(*TTI)) ||
!has_single_bit(VL.size())) {
LLVM_DEBUG(dbgs() << "SLP: Reshuffling scalars not yet supported "
"for nodes with padding.\n");
newTreeEntry(VL, std::nullopt /*not vectorized*/, S, UserTreeIdx);
return false;
}
LLVM_DEBUG(dbgs() << "SLP: Shuffle for reused scalars.\n");
if (NumUniqueScalarValues <= 1 ||
(UniquePositions.size() == 1 && all_of(UniqueValues,
[](Value *V) {
return isa<UndefValue>(V) ||
!isConstant(V);
})) ||
!llvm::has_single_bit<uint32_t>(NumUniqueScalarValues)) {
if (NumUniqueScalarValues <= 1 || !IsFullVectors ||
(UniquePositions.size() == 1 && all_of(UniqueValues, [](Value *V) {
return isa<UndefValue>(V) || !isConstant(V);
}))) {
if (DoNotFail && UniquePositions.size() > 1 &&
NumUniqueScalarValues > 1 && S.MainOp->isSafeToRemove() &&
all_of(UniqueValues, [=](Value *V) {
@@ -7555,7 +7602,9 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
areAllUsersVectorized(cast<Instruction>(V),
UserIgnoreList);
})) {
unsigned PWSz = PowerOf2Ceil(UniqueValues.size());
// Find the number of elements, which forms full vectors.
unsigned PWSz = getFullVectorNumberOfElements(
*TTI, UniqueValues.front()->getType(), UniqueValues.size());
if (PWSz == VL.size()) {
ReuseShuffleIndices.clear();
} else {
@@ -9793,9 +9842,6 @@ public:
return nullptr;
Value *VecBase = nullptr;
ArrayRef<Value *> VL = E->Scalars;
// If the resulting type is scalarized, do not adjust the cost.
if (NumParts == VL.size())
return nullptr;
// Check if it can be considered reused if same extractelements were
// vectorized already.
bool PrevNodeFound = any_of(
@@ -9911,7 +9957,8 @@ public:
assert(!CommonMask.empty() && "Expected non-empty common mask.");
auto *MaskVecTy = getWidenedType(ScalarTy, Mask.size());
unsigned NumParts = TTI.getNumberOfParts(MaskVecTy);
if (NumParts == 0 || NumParts >= Mask.size())
if (NumParts == 0 || NumParts >= Mask.size() ||
MaskVecTy->getNumElements() % NumParts != 0)
NumParts = 1;
unsigned SliceSize = getPartNumElems(Mask.size(), NumParts);
const auto *It =
@@ -9928,7 +9975,8 @@ public:
assert(!CommonMask.empty() && "Expected non-empty common mask.");
auto *MaskVecTy = getWidenedType(ScalarTy, Mask.size());
unsigned NumParts = TTI.getNumberOfParts(MaskVecTy);
if (NumParts == 0 || NumParts >= Mask.size())
if (NumParts == 0 || NumParts >= Mask.size() ||
MaskVecTy->getNumElements() % NumParts != 0)
NumParts = 1;
unsigned SliceSize = getPartNumElems(Mask.size(), NumParts);
const auto *It =
@@ -10450,7 +10498,7 @@ BoUpSLP::getEntryCost(const TreeEntry *E, ArrayRef<Value *> VectorizedVals,
InsertMask[Idx] = I + 1;
}
unsigned VecScalarsSz = PowerOf2Ceil(NumElts);
if (NumOfParts > 0)
if (NumOfParts > 0 && NumOfParts < NumElts)
VecScalarsSz = PowerOf2Ceil((NumElts + NumOfParts - 1) / NumOfParts);
unsigned VecSz = (1 + OffsetEnd / VecScalarsSz - OffsetBeg / VecScalarsSz) *
VecScalarsSz;
@@ -13579,7 +13627,8 @@ ResTy BoUpSLP::processBuildVector(const TreeEntry *E, Type *ScalarTy,
Type *OrigScalarTy = GatheredScalars.front()->getType();
auto *VecTy = getWidenedType(ScalarTy, GatheredScalars.size());
unsigned NumParts = TTI->getNumberOfParts(VecTy);
if (NumParts == 0 || NumParts >= GatheredScalars.size())
if (NumParts == 0 || NumParts >= GatheredScalars.size() ||
VecTy->getNumElements() % NumParts != 0)
NumParts = 1;
if (!all_of(GatheredScalars, IsaPred<UndefValue>)) {
// Check for gathered extracts.
@@ -17785,7 +17834,7 @@ bool SLPVectorizerPass::tryToVectorizeList(ArrayRef<Value *> VL, BoUpSLP &R,
for (unsigned I = NextInst; I < MaxInst; ++I) {
unsigned ActualVF = std::min(MaxInst - I, VF);
if (!has_single_bit(ActualVF))
if (!hasFullVectorsOrPowerOf2(*TTI, ScalarTy, ActualVF))
continue;
if (MaxVFOnly && ActualVF < MaxVF)

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@@ -1,21 +1,29 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -passes=slp-vectorizer -S -mtriple=riscv64-unknown-linux -mattr=+v -slp-threshold=-100 | FileCheck %s
; RUN: opt < %s -passes=slp-vectorizer -S -mtriple=riscv64-unknown-linux -mattr=+v -slp-threshold=-100 | FileCheck %s --check-prefix=RISCV
; RUN: opt < %s -passes=slp-vectorizer -S -mtriple=x86_64-unknown-linux -slp-threshold=-100 | FileCheck %s
; RUN: opt < %s -passes=slp-vectorizer -S -mtriple=aarch64-unknown-linux -slp-threshold=-100 | FileCheck %s
; REQUIRES: aarch64-registered-target, x86-registered-target, riscv-registered-target
define i64 @test(ptr %p) {
; RISCV-LABEL: @test(
; RISCV-NEXT: entry:
; RISCV-NEXT: [[ARRAYIDX_4:%.*]] = getelementptr inbounds i64, ptr [[P:%.*]], i64 4
; RISCV-NEXT: [[TMP0:%.*]] = load <4 x i64>, ptr [[P]], align 4
; RISCV-NEXT: [[TMP1:%.*]] = load <2 x i64>, ptr [[ARRAYIDX_4]], align 4
; RISCV-NEXT: [[TMP2:%.*]] = shufflevector <4 x i64> [[TMP0]], <4 x i64> poison, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 0, i32 0>
; RISCV-NEXT: [[TMP3:%.*]] = call <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64> [[TMP2]], <4 x i64> [[TMP0]], i64 0)
; RISCV-NEXT: [[TMP4:%.*]] = call <8 x i64> @llvm.vector.insert.v8i64.v2i64(<8 x i64> [[TMP3]], <2 x i64> [[TMP1]], i64 4)
; RISCV-NEXT: [[TMP5:%.*]] = mul <8 x i64> [[TMP4]], <i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42>
; RISCV-NEXT: [[TMP6:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP5]])
; RISCV-NEXT: ret i64 [[TMP6]]
;
; CHECK-LABEL: @test(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ARRAYIDX_4:%.*]] = getelementptr inbounds i64, ptr [[P:%.*]], i64 4
; CHECK-NEXT: [[TMP0:%.*]] = load <4 x i64>, ptr [[P]], align 4
; CHECK-NEXT: [[TMP1:%.*]] = load <2 x i64>, ptr [[ARRAYIDX_4]], align 4
; CHECK-NEXT: [[TMP2:%.*]] = shufflevector <4 x i64> [[TMP0]], <4 x i64> poison, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 0, i32 0>
; CHECK-NEXT: [[TMP3:%.*]] = call <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64> [[TMP2]], <4 x i64> [[TMP0]], i64 0)
; CHECK-NEXT: [[TMP4:%.*]] = call <8 x i64> @llvm.vector.insert.v8i64.v2i64(<8 x i64> [[TMP3]], <2 x i64> [[TMP1]], i64 4)
; CHECK-NEXT: [[TMP5:%.*]] = mul <8 x i64> [[TMP4]], <i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42>
; CHECK-NEXT: [[TMP6:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP5]])
; CHECK-NEXT: ret i64 [[TMP6]]
; CHECK-NEXT: [[TMP0:%.*]] = load <6 x i64>, ptr [[P:%.*]], align 4
; CHECK-NEXT: [[TMP1:%.*]] = shufflevector <6 x i64> [[TMP0]], <6 x i64> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 0, i32 0>
; CHECK-NEXT: [[TMP2:%.*]] = mul <8 x i64> [[TMP1]], <i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42, i64 42>
; CHECK-NEXT: [[TMP3:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP2]])
; CHECK-NEXT: ret i64 [[TMP3]]
;
entry:
%arrayidx.1 = getelementptr inbounds i64, ptr %p, i64 1