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| author | Florian Hahn <flo@fhahn.com> | 2021-08-05 14:50:37 +0100 |
|---|---|---|
| committer | Florian Hahn <flo@fhahn.com> | 2021-08-05 15:36:31 +0100 |
| commit | 38b098be6605494cc7308ea9b08f920c4c3fe4ce (patch) | |
| tree | ce5228511d05adf512574de1298d290aef532e9c | |
| parent | 06206a8cd1b1538e265f79e245c34180c640e334 (diff) | |
| download | llvm-38b098be6605494cc7308ea9b08f920c4c3fe4ce.tar.gz | |
[VectorCombine] Limit scalarization known non-poison indices.
We can only trust the range of the index if it is guaranteed
non-poison.
Fixes PR50949.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D107364
| -rw-r--r-- | llvm/lib/Transforms/Vectorize/VectorCombine.cpp | 3 | ||||
| -rw-r--r-- | llvm/test/Transforms/VectorCombine/load-insert-store.ll | 10 |
2 files changed, 9 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Vectorize/VectorCombine.cpp b/llvm/lib/Transforms/Vectorize/VectorCombine.cpp index d18bcd34620c..e138e890acb2 100644 --- a/llvm/lib/Transforms/Vectorize/VectorCombine.cpp +++ b/llvm/lib/Transforms/Vectorize/VectorCombine.cpp @@ -781,6 +781,9 @@ static bool canScalarizeAccess(FixedVectorType *VecTy, Value *Idx, if (auto *C = dyn_cast<ConstantInt>(Idx)) return C->getValue().ult(VecTy->getNumElements()); + if (!isGuaranteedNotToBePoison(Idx, &AC)) + return false; + APInt Zero(Idx->getType()->getScalarSizeInBits(), 0); APInt MaxElts(Idx->getType()->getScalarSizeInBits(), VecTy->getNumElements()); ConstantRange ValidIndices(Zero, MaxElts); diff --git a/llvm/test/Transforms/VectorCombine/load-insert-store.ll b/llvm/test/Transforms/VectorCombine/load-insert-store.ll index 93ad6e7a4a86..5c3f1659e35f 100644 --- a/llvm/test/Transforms/VectorCombine/load-insert-store.ll +++ b/llvm/test/Transforms/VectorCombine/load-insert-store.ll @@ -310,9 +310,10 @@ entry: define void @insert_store_nonconst_index_known_valid_by_and_but_may_be_poison(<16 x i8>* %q, i8 zeroext %s, i32 %idx) { ; CHECK-LABEL: @insert_store_nonconst_index_known_valid_by_and_but_may_be_poison( ; CHECK-NEXT: entry: +; CHECK-NEXT: [[TMP0:%.*]] = load <16 x i8>, <16 x i8>* [[Q:%.*]], align 16 ; CHECK-NEXT: [[IDX_CLAMPED:%.*]] = and i32 [[IDX:%.*]], 7 -; CHECK-NEXT: [[TMP0:%.*]] = getelementptr inbounds <16 x i8>, <16 x i8>* [[Q:%.*]], i32 0, i32 [[IDX_CLAMPED]] -; CHECK-NEXT: store i8 [[S:%.*]], i8* [[TMP0]], align 1 +; CHECK-NEXT: [[VECINS:%.*]] = insertelement <16 x i8> [[TMP0]], i8 [[S:%.*]], i32 [[IDX_CLAMPED]] +; CHECK-NEXT: store <16 x i8> [[VECINS]], <16 x i8>* [[Q]], align 16 ; CHECK-NEXT: ret void ; entry: @@ -412,9 +413,10 @@ entry: define void @insert_store_nonconst_index_known_valid_by_urem_but_may_be_poison(<16 x i8>* %q, i8 zeroext %s, i32 %idx) { ; CHECK-LABEL: @insert_store_nonconst_index_known_valid_by_urem_but_may_be_poison( ; CHECK-NEXT: entry: +; CHECK-NEXT: [[TMP0:%.*]] = load <16 x i8>, <16 x i8>* [[Q:%.*]], align 16 ; CHECK-NEXT: [[IDX_CLAMPED:%.*]] = urem i32 [[IDX:%.*]], 16 -; CHECK-NEXT: [[TMP0:%.*]] = getelementptr inbounds <16 x i8>, <16 x i8>* [[Q:%.*]], i32 0, i32 [[IDX_CLAMPED]] -; CHECK-NEXT: store i8 [[S:%.*]], i8* [[TMP0]], align 1 +; CHECK-NEXT: [[VECINS:%.*]] = insertelement <16 x i8> [[TMP0]], i8 [[S:%.*]], i32 [[IDX_CLAMPED]] +; CHECK-NEXT: store <16 x i8> [[VECINS]], <16 x i8>* [[Q]], align 16 ; CHECK-NEXT: ret void ; entry: |