diff options
Diffstat (limited to 'llvm/test/Transforms')
| -rw-r--r-- | llvm/test/Transforms/InstSimplify/assume.ll | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstSimplify/assume.ll b/llvm/test/Transforms/InstSimplify/assume.ll index 2487a9c8bb1..2edcc0c2367 100644 --- a/llvm/test/Transforms/InstSimplify/assume.ll +++ b/llvm/test/Transforms/InstSimplify/assume.ll @@ -10,5 +10,41 @@ define void @test1() { } +; The alloca guarantees that the low bits of %a are zero because of alignment. +; The assume says the opposite. The assume is processed last, so that's the +; return value. There's no way to win (we can't undo transforms that happened +; based on half-truths), so just don't crash. + +define i64 @PR31809() { +; CHECK-LABEL: @PR31809( +; CHECK-NEXT: ret i64 3 +; + %a = alloca i32 + %t1 = ptrtoint i32* %a to i64 + %cond = icmp eq i64 %t1, 3 + call void @llvm.assume(i1 %cond) + ret i64 %t1 +} + +; Similar to above: there's no way to know which assumption is truthful, +; so just don't crash. The second icmp+assume gets processed later, so that +; determines the return value. This can be improved by permanently invalidating +; the cached assumptions for this function. + +define i8 @conflicting_assumptions(i8 %x) { +; CHECK-LABEL: @conflicting_assumptions( +; CHECK-NEXT: call void @llvm.assume(i1 false) +; CHECK-NEXT: [[COND2:%.*]] = icmp eq i8 %x, 4 +; CHECK-NEXT: call void @llvm.assume(i1 [[COND2]]) +; CHECK-NEXT: ret i8 5 +; + %add = add i8 %x, 1 + %cond1 = icmp eq i8 %x, 3 + call void @llvm.assume(i1 %cond1) + %cond2 = icmp eq i8 %x, 4 + call void @llvm.assume(i1 %cond2) + ret i8 %add +} + declare void @llvm.assume(i1) nounwind |
