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1; REQUIRES: asserts
2; RUN: opt -regions -analyze -enable-new-pm=0 < %s | FileCheck %s
3; RUN: opt < %s -passes='print<regions>' 2>&1 | FileCheck %s
4
5; While working on improvements to the region info analysis, this test
6; case caused an incorrect region bb2 => bb3 to be detected. It is incorrect
7; because bb2 has an outgoing edge to bb4. This is interesting because
8; bb2 dom bb3 and bb3 pdom bb2, which should have been enough to prevent incoming
9; forward edges into the region and outgoing forward edges from the region.
10
11define void @meread_() nounwind {
12bb:
13   br label %bb1
14
15bb1:                                              ; preds = %bb4, %bb
16   br label %bb2
17
18bb2:                                              ; preds = %bb1
19  br i1 true, label %bb3, label %bb4
20
21bb3:                                              ; preds = %bb2
22  br i1 true, label %bb4, label %bb5
23
24bb4:                                              ; preds = %bb3, %bb2
25   br label %bb1
26
27bb5:                                              ; preds = %bb3
28   ret void
29 }
30
31; CHECK:      [0] bb => <Function Return>
32; CHECK-NEXT:   [1] bb1 => bb5
33; CHECK-NEXT: End region tree
34