Index: llvm/trunk/test/Analysis/RegionInfo/outgoing_edge.ll =================================================================== --- llvm/trunk/test/Analysis/RegionInfo/outgoing_edge.ll +++ llvm/trunk/test/Analysis/RegionInfo/outgoing_edge.ll @@ -0,0 +1,33 @@ +; REQUIRES: asserts +; RUN: opt -regions -analyze < %s | FileCheck %s +; RUN: opt < %s -passes='print' 2>&1 | FileCheck %s + +; While working on improvements to the region info analysis, this test +; case caused an incorrect region bb2 => bb3 to be detected. It is incorrect +; because bb2 has an outgoing edge to bb4. This is interesting because +; bb2 dom bb3 and bb3 pdom bb2, which should have been enough to prevent incoming +; forward edges into the region and outgoing forward edges from the region. + +define void @meread_() nounwind { +bb: + br label %bb1 + +bb1: ; preds = %bb4, %bb + br label %bb2 + +bb2: ; preds = %bb1 + br i1 true, label %bb3, label %bb4 + +bb3: ; preds = %bb2 + br i1 true, label %bb4, label %bb5 + +bb4: ; preds = %bb3, %bb2 + br label %bb1 + +bb5: ; preds = %bb3 + ret void + } + +; CHECK: [0] bb => +; CHECK-NEXT: [1] bb1 => bb5 +; CHECK-NEXT: End region tree