diff options
Diffstat (limited to 'llvm/test/Transforms/InstCombine/redundant-left-shift-input-masking-pr49778.ll')
| -rw-r--r-- | llvm/test/Transforms/InstCombine/redundant-left-shift-input-masking-pr49778.ll | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/redundant-left-shift-input-masking-pr49778.ll b/llvm/test/Transforms/InstCombine/redundant-left-shift-input-masking-pr49778.ll new file mode 100644 index 000000000000..8d70733ed03d --- /dev/null +++ b/llvm/test/Transforms/InstCombine/redundant-left-shift-input-masking-pr49778.ll @@ -0,0 +1,20 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -instcombine -S | FileCheck %s + +; PR49778: this should not be folded to 0. +define i32 @src(i1 %x2) { +; CHECK-LABEL: @src( +; CHECK-NEXT: [[X13:%.*]] = zext i1 [[X2:%.*]] to i32 +; CHECK-NEXT: [[_7:%.*]] = shl i32 -1, [[X13]] +; CHECK-NEXT: [[MASK:%.*]] = xor i32 [[_7]], -1 +; CHECK-NEXT: [[_8:%.*]] = and i32 [[MASK]], [[X13]] +; CHECK-NEXT: [[_9:%.*]] = shl i32 [[_8]], [[X13]] +; CHECK-NEXT: ret i32 [[_9]] +; + %x13 = zext i1 %x2 to i32 + %_7 = shl i32 4294967295, %x13 + %mask = xor i32 %_7, 4294967295 + %_8 = and i32 %mask, %x13 + %_9 = shl i32 %_8, %x13 + ret i32 %_9 +} |