diff options
Diffstat (limited to 'llvm/test/Transforms/InstCombine/select.ll')
| -rw-r--r-- | llvm/test/Transforms/InstCombine/select.ll | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/select.ll b/llvm/test/Transforms/InstCombine/select.ll index d625f3b1b33..d1d8b888713 100644 --- a/llvm/test/Transforms/InstCombine/select.ll +++ b/llvm/test/Transforms/InstCombine/select.ll @@ -1236,3 +1236,41 @@ define i32 @test75(i32 %x) { ; CHECK-NEXT: [[SEL:%[a-z0-9]+]] = select i1 [[CMP]], i32 68, i32 %x ; CHECK-NEXT: ret i32 [[SEL]] } + +@under_aligned = external global i32, align 1 + +define i32 @test76(i1 %flag, i32* %x) { +; The load here must not be speculated around the select. One side of the +; select is trivially dereferencable but may have a lower alignment than the +; load does. +; CHECK-LABEL: @test76( +; CHECK: store i32 0, i32* %x +; CHECK: %[[P:.*]] = select i1 %flag, i32* @under_aligned, i32* %x +; CHECK: load i32* %[[P]] + + store i32 0, i32* %x + %p = select i1 %flag, i32* @under_aligned, i32* %x + %v = load i32* %p + ret i32 %v +} + +declare void @scribble_on_memory(i32*) + +define i32 @test77(i1 %flag, i32* %x) { +; The load here must not be speculated around the select. One side of the +; select is trivially dereferencable but may have a lower alignment than the +; load does. +; CHECK-LABEL: @test77( +; CHECK: %[[A:.*]] = alloca i32, align 1 +; CHECK: call void @scribble_on_memory(i32* %[[A]]) +; CHECK: store i32 0, i32* %x +; CHECK: %[[P:.*]] = select i1 %flag, i32* %[[A]], i32* %x +; CHECK: load i32* %[[P]] + + %under_aligned = alloca i32, align 1 + call void @scribble_on_memory(i32* %under_aligned) + store i32 0, i32* %x + %p = select i1 %flag, i32* %under_aligned, i32* %x + %v = load i32* %p + ret i32 %v +} |
