diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/shuffle_select.ll | 10 |
2 files changed, 12 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp index 665064c4c8d..28d5f187c3d 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp @@ -1353,8 +1353,8 @@ static Instruction *foldSelectShuffle(ShuffleVectorInst &Shuf, // Canonicalize to choose from operand 0 first. unsigned NumElts = Shuf.getType()->getVectorNumElements(); if (Shuf.getMaskValue(0) >= (int)NumElts) { - assert(!isa<UndefValue>(Shuf.getOperand(1)) && - "Not expecting undef shuffle operand with select mask"); + // TODO: Can we assert that both operands of a shuffle-select are not undef + // (otherwise, it would have been folded by instsimplify? Shuf.commute(); return &Shuf; } diff --git a/llvm/test/Transforms/InstCombine/shuffle_select.ll b/llvm/test/Transforms/InstCombine/shuffle_select.ll index 991f390682a..6cda586f913 100644 --- a/llvm/test/Transforms/InstCombine/shuffle_select.ll +++ b/llvm/test/Transforms/InstCombine/shuffle_select.ll @@ -1454,3 +1454,13 @@ define <4 x i8> @or_add_2_vars(<4 x i8> %v, <4 x i8> %v1) { ret <4 x i8> %t3 } +; The undef operand is used to simplify the shuffle mask, but don't assert that too soon. + +define <4 x i32> @PR41419(<4 x i32> %v) { +; CHECK-LABEL: @PR41419( +; CHECK-NEXT: ret <4 x i32> [[V:%.*]] +; + %s = shufflevector <4 x i32> %v, <4 x i32> undef, <4 x i32> <i32 4, i32 5, i32 2, i32 7> + ret <4 x i32> %s +} + |
