diff options
Diffstat (limited to 'test/Transforms/JumpThreading/assume.ll')
| -rw-r--r-- | test/Transforms/JumpThreading/assume.ll | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/test/Transforms/JumpThreading/assume.ll b/test/Transforms/JumpThreading/assume.ll index 53010b71c7285..3a039676e172b 100644 --- a/test/Transforms/JumpThreading/assume.ll +++ b/test/Transforms/JumpThreading/assume.ll @@ -56,6 +56,50 @@ return: ; preds = %entry, %if.then ret i32 %retval.0 } +@g = external global i32 + +; Check that we do prove a fact using an assume within the block. +; FIXME: We can fold the assume based on the semantics of assume. +; CHECK-LABEL: @can_fold_assume +; CHECK: %notnull = icmp ne i32* %array, null +; CHECK-NEXT: call void @llvm.assume(i1 %notnull) +; CHECK-NEXT: ret void +define void @can_fold_assume(i32* %array) { + %notnull = icmp ne i32* %array, null + call void @llvm.assume(i1 %notnull) + br i1 %notnull, label %normal, label %error + +normal: + ret void + +error: + store atomic i32 0, i32* @g unordered, align 4 + ret void +} + +declare void @f(i1) +declare void @exit() +; We can fold the assume but not the uses before the assume. +define void @dont_fold_incorrectly(i32* %array) { +; CHECK-LABEL:@dont_fold_incorrectly +; CHECK: @f(i1 %notnull) +; CHECK-NEXT: exit() +; CHECK-NEXT: assume(i1 %notnull) +; CHECK-NEXT: ret void + %notnull = icmp ne i32* %array, null + call void @f(i1 %notnull) + call void @exit() + call void @llvm.assume(i1 %notnull) + br i1 %notnull, label %normal, label %error + +normal: + ret void + +error: + store atomic i32 0, i32* @g unordered, align 4 + ret void +} + ; Function Attrs: nounwind declare void @llvm.assume(i1) #1 |