New Test-Case for Region Analysis

[nandini12396]

Summary

While working on improvements to region info analysis, this test case caused an incorrect region bb2 => bb3 to be detected.

[grosser]

Thank you Nandini!

llvm/trunk/test/Analysis/RegionInfo/outgoing_edge_1.ll

+; REQUIRES: asserts
+; RUN: opt -regions -analyze < %s | FileCheck %s
+; RUN: opt < %s -passes='print<regions>' 2>&1 | FileCheck %s
+
+; While working on improvements to region info analysis, this test
+; case caused an incorrect region bb2 => bb3 to be detected.
+
+define internal i8 @main_read() nounwind {
+bb:
+   br label %bb1
+
+bb1:
+   br i1 true, label %bb2, label %bb7
+
+bb2:
+  br i1 true, label %bb4, label %bb3
+
+bb3:
+  br i1 true, label %bb4, label %bb8
+
+bb4:
+   br label %bb5
+
+bb5:
+   br label %bb6
+
+bb6:
+   br label %bb1
+
+bb7:
+   br label %bb5
+
+bb8:
+   ret i8 1
+}
+
+; CHECK:    [0] bb => <Function Return>
+; CHECK-NEXT: [1] bb1 => bb8
+; CHECK-NEXT: End Region tree