[llvm] e335e8a - [InstCombine] Update instcombine for vectorOps to use new shufflevector semantics
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Tue May 16 23:58:51 PDT 2023
Author: ManuelJBrito
Date: 2023-05-17T07:56:45+01:00
New Revision: e335e8a43287b8258c719d7a21c4264b0550c554
URL: https://github.com/llvm/llvm-project/commit/e335e8a43287b8258c719d7a21c4264b0550c554
DIFF: https://github.com/llvm/llvm-project/commit/e335e8a43287b8258c719d7a21c4264b0550c554.diff
LOG: [InstCombine] Update instcombine for vectorOps to use new shufflevector semantics
This patch updates the transformations in InstCombineVectorOps to use the new
hufflevector semantics that say that undefined values in the mask yield poison.
To prevent miscompilations we have to match with m_Poison instead of m_Undef.
Otherwise, we might introduce poison where there was previously undef.
Differential Revision: https://reviews.llvm.org/D150039
Added:
Modified:
llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
llvm/test/Transforms/InstCombine/broadcast.ll
llvm/test/Transforms/InstCombine/vec_shuffle-inseltpoison.ll
llvm/test/Transforms/InstCombine/vec_shuffle.ll
llvm/test/Transforms/SLPVectorizer/X86/pr49081.ll
Removed:
################################################################################
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
index d39840643cfea..4bab964aa14d6 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
@@ -640,11 +640,11 @@ static bool collectSingleShuffleElements(Value *V, Value *LHS, Value *RHS,
return false;
unsigned InsertedIdx = cast<ConstantInt>(IdxOp)->getZExtValue();
- if (isa<UndefValue>(ScalarOp)) { // inserting undef into vector.
+ if (isa<PoisonValue>(ScalarOp)) { // inserting poison into vector.
// We can handle this if the vector we are inserting into is
// transitively ok.
if (collectSingleShuffleElements(VecOp, LHS, RHS, Mask)) {
- // If so, update the mask to reflect the inserted undef.
+ // If so, update the mask to reflect the inserted poison.
Mask[InsertedIdx] = -1;
return true;
}
@@ -1240,11 +1240,11 @@ static Instruction *foldInsSequenceIntoSplat(InsertElementInst &InsElt) {
if (FirstIE == &InsElt)
return nullptr;
- // If we are not inserting into an undef vector, make sure we've seen an
+ // If we are not inserting into a poison vector, make sure we've seen an
// insert into every element.
// TODO: If the base vector is not undef, it might be better to create a splat
// and then a select-shuffle (blend) with the base vector.
- if (!match(FirstIE->getOperand(0), m_Undef()))
+ if (!match(FirstIE->getOperand(0), m_Poison()))
if (!ElementPresent.all())
return nullptr;
@@ -1255,7 +1255,7 @@ static Instruction *foldInsSequenceIntoSplat(InsertElementInst &InsElt) {
if (!cast<ConstantInt>(FirstIE->getOperand(2))->isZero())
FirstIE = InsertElementInst::Create(PoisonVec, SplatVal, Zero, "", &InsElt);
- // Splat from element 0, but replace absent elements with undef in the mask.
+ // Splat from element 0, but replace absent elements with poison in the mask.
SmallVector<int, 16> Mask(NumElements, 0);
for (unsigned i = 0; i != NumElements; ++i)
if (!ElementPresent[i])
@@ -3060,7 +3060,7 @@ Instruction *InstCombinerImpl::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
for (unsigned i = 0; i < VWidth; ++i) {
int eltMask;
if (Mask[i] < 0) {
- // This element is an undef value.
+ // This element is a poison value.
eltMask = -1;
} else if (Mask[i] < (int)LHSWidth) {
// This element is from left hand side vector operand.
@@ -3069,27 +3069,27 @@ Instruction *InstCombinerImpl::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
// new mask value for the element.
if (newLHS != LHS) {
eltMask = LHSMask[Mask[i]];
- // If the value selected is an undef value, explicitly specify it
+ // If the value selected is an poison value, explicitly specify it
// with a -1 mask value.
- if (eltMask >= (int)LHSOp0Width && isa<UndefValue>(LHSOp1))
+ if (eltMask >= (int)LHSOp0Width && isa<PoisonValue>(LHSOp1))
eltMask = -1;
} else
eltMask = Mask[i];
} else {
// This element is from right hand side vector operand
//
- // If the value selected is an undef value, explicitly specify it
+ // If the value selected is a poison value, explicitly specify it
// with a -1 mask value. (case 1)
- if (match(RHS, m_Undef()))
+ if (match(RHS, m_Poison()))
eltMask = -1;
// If RHS is going to be replaced (case 3 or 4), calculate the
// new mask value for the element.
else if (newRHS != RHS) {
eltMask = RHSMask[Mask[i]-LHSWidth];
- // If the value selected is an undef value, explicitly specify it
+ // If the value selected is an poison value, explicitly specify it
// with a -1 mask value.
if (eltMask >= (int)RHSOp0Width) {
- assert(match(RHSShuffle->getOperand(1), m_Undef()) &&
+ assert(match(RHSShuffle->getOperand(1), m_Poison()) &&
"should have been check above");
eltMask = -1;
}
@@ -3120,7 +3120,7 @@ Instruction *InstCombinerImpl::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
// or is a splat, do the replacement.
if (isSplat || newMask == LHSMask || newMask == RHSMask || newMask == Mask) {
if (!newRHS)
- newRHS = UndefValue::get(newLHS->getType());
+ newRHS = PoisonValue::get(newLHS->getType());
return new ShuffleVectorInst(newLHS, newRHS, newMask);
}
diff --git a/llvm/test/Transforms/InstCombine/broadcast.ll b/llvm/test/Transforms/InstCombine/broadcast.ll
index 6f820430c466d..5e5c3d6a03380 100644
--- a/llvm/test/Transforms/InstCombine/broadcast.ll
+++ b/llvm/test/Transforms/InstCombine/broadcast.ll
@@ -76,8 +76,9 @@ define <4 x float> @good5(float %v) {
define <4 x float> @splat_undef1(float %arg) {
; CHECK-LABEL: @splat_undef1(
-; CHECK-NEXT: [[TMP1:%.*]] = insertelement <4 x float> poison, float [[ARG:%.*]], i64 0
-; CHECK-NEXT: [[T6:%.*]] = shufflevector <4 x float> [[TMP1]], <4 x float> poison, <4 x i32> <i32 poison, i32 0, i32 0, i32 0>
+; CHECK-NEXT: [[T4:%.*]] = insertelement <4 x float> undef, float [[ARG:%.*]], i64 1
+; CHECK-NEXT: [[T5:%.*]] = insertelement <4 x float> [[T4]], float [[ARG:%.*]], i64 2
+; CHECK-NEXT: [[T6:%.*]] = insertelement <4 x float> [[T5]], float [[ARG:%.*]], i64 3
; CHECK-NEXT: ret <4 x float> [[T6]]
;
%t = insertelement <4 x float> undef, float %arg, i32 1
@@ -92,7 +93,8 @@ define <4 x float> @splat_undef1(float %arg) {
define <4 x float> @splat_undef2(float %arg) {
; CHECK-LABEL: @splat_undef2(
; CHECK-NEXT: [[T:%.*]] = insertelement <4 x float> undef, float [[ARG:%.*]], i64 0
-; CHECK-NEXT: [[T6:%.*]] = shufflevector <4 x float> [[T]], <4 x float> poison, <4 x i32> <i32 0, i32 poison, i32 0, i32 0>
+; CHECK-NEXT: [[T5:%.*]] = insertelement <4 x float> [[T]], float [[ARG:%.*]], i64 2
+; CHECK-NEXT: [[T6:%.*]] = insertelement <4 x float> [[T5]], float [[ARG:%.*]], i64 3
; CHECK-NEXT: ret <4 x float> [[T6]]
;
%t = insertelement <4 x float> undef, float %arg, i32 0
@@ -131,8 +133,9 @@ define <1 x float> @bad4(float %arg) {
define <4 x float> @splat_undef3(float %arg) {
; CHECK-LABEL: @splat_undef3(
; CHECK-NEXT: [[T:%.*]] = insertelement <4 x float> undef, float [[ARG:%.*]], i64 0
-; CHECK-NEXT: [[T4:%.*]] = shufflevector <4 x float> [[T]], <4 x float> poison, <4 x i32> <i32 0, i32 0, i32 poison, i32 poison>
-; CHECK-NEXT: [[T6:%.*]] = shufflevector <4 x float> [[T]], <4 x float> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT: [[T4:%.*]] = insertelement <4 x float> [[T]], float [[ARG:%.*]], i64 1
+; CHECK-NEXT: [[T5:%.*]] = insertelement <4 x float> [[T4]], float [[ARG:%.*]], i64 2
+; CHECK-NEXT: [[T6:%.*]] = insertelement <4 x float> [[T5]], float [[ARG:%.*]], i64 3
; CHECK-NEXT: [[T7:%.*]] = fadd <4 x float> [[T6]], [[T4]]
; CHECK-NEXT: ret <4 x float> [[T7]]
;
diff --git a/llvm/test/Transforms/InstCombine/vec_shuffle-inseltpoison.ll b/llvm/test/Transforms/InstCombine/vec_shuffle-inseltpoison.ll
index 65f1ab290dfa9..f664c3e78914c 100644
--- a/llvm/test/Transforms/InstCombine/vec_shuffle-inseltpoison.ll
+++ b/llvm/test/Transforms/InstCombine/vec_shuffle-inseltpoison.ll
@@ -152,7 +152,7 @@ define <4 x i32> @test10(<4 x i32> %t5) {
define <8 x i8> @test11(<16 x i8> %t6) {
; CHECK-LABEL: @test11(
-; CHECK-NEXT: [[T3:%.*]] = shufflevector <16 x i8> [[T6:%.*]], <16 x i8> undef, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+; CHECK-NEXT: [[T3:%.*]] = shufflevector <16 x i8> [[T6:%.*]], <16 x i8> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
; CHECK-NEXT: ret <8 x i8> [[T3]]
;
%t1 = shufflevector <16 x i8> %t6, <16 x i8> poison, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
diff --git a/llvm/test/Transforms/InstCombine/vec_shuffle.ll b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
index b67c0de6ccb01..0081da2c0aad7 100644
--- a/llvm/test/Transforms/InstCombine/vec_shuffle.ll
+++ b/llvm/test/Transforms/InstCombine/vec_shuffle.ll
@@ -158,7 +158,7 @@ define <4 x i32> @test10(<4 x i32> %t5) {
define <8 x i8> @test11(<16 x i8> %t6) {
; CHECK-LABEL: @test11(
-; CHECK-NEXT: [[T3:%.*]] = shufflevector <16 x i8> [[T6:%.*]], <16 x i8> undef, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
+; CHECK-NEXT: [[T3:%.*]] = shufflevector <16 x i8> [[T6:%.*]], <16 x i8> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
; CHECK-NEXT: ret <8 x i8> [[T3]]
;
%t1 = shufflevector <16 x i8> %t6, <16 x i8> undef, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/pr49081.ll b/llvm/test/Transforms/SLPVectorizer/X86/pr49081.ll
index 9be8fb76ecb5e..740bf71f60e44 100644
--- a/llvm/test/Transforms/SLPVectorizer/X86/pr49081.ll
+++ b/llvm/test/Transforms/SLPVectorizer/X86/pr49081.ll
@@ -8,7 +8,7 @@ define dso_local <4 x float> @foo(<4 x i32> %0) {
; CHECK-NEXT: [[TMP2:%.*]] = extractelement <4 x i32> [[TMP0:%.*]], i64 1
; CHECK-NEXT: [[TMP3:%.*]] = sitofp i32 [[TMP2]] to float
; CHECK-NEXT: [[TMP4:%.*]] = insertelement <4 x float> undef, float [[TMP3]], i64 0
-; CHECK-NEXT: [[TMP5:%.*]] = shufflevector <4 x float> [[TMP4]], <4 x float> poison, <4 x i32> <i32 0, i32 0, i32 poison, i32 poison>
+; CHECK-NEXT: [[TMP5:%.*]] = insertelement <4 x float> [[TMP4]], float [[TMP3]], i64 1
; CHECK-NEXT: [[TMP6:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> poison, <2 x i32> <i32 2, i32 3>
; CHECK-NEXT: [[TMP7:%.*]] = sitofp <2 x i32> [[TMP6]] to <2 x float>
; CHECK-NEXT: [[TMP8:%.*]] = shufflevector <2 x float> [[TMP7]], <2 x float> poison, <4 x i32> <i32 0, i32 1, i32 poison, i32 poison>
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