xref: /llvm-project/llvm/test/Transforms/NewGVN/br-identical.ll (revision 229640343e400394b315c6798c7c19e8a9bd188c)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
2; RUN: opt -passes=newgvn -S -o - %s | FileCheck %s
3
4; If a branch has two identical successors, we cannot declare either dead.
5
6define void @widget(i1 %p) {
7; CHECK-LABEL: define void @widget(
8; CHECK-SAME: i1 [[P:%.*]]) {
9; CHECK-NEXT:  entry:
10; CHECK-NEXT:    br label [[BB2:%.*]]
11; CHECK:       bb2:
12; CHECK-NEXT:    [[T1:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[T2:%.*]], [[BB7:%.*]] ]
13; CHECK-NEXT:    [[T2]] = add i64 [[T1]], 1
14; CHECK-NEXT:    [[T3:%.*]] = icmp ult i64 0, [[T2]]
15; CHECK-NEXT:    br i1 [[T3]], label [[BB3:%.*]], label [[BB4:%.*]]
16; CHECK:       bb3:
17; CHECK-NEXT:    [[T4:%.*]] = call i64 @f()
18; CHECK-NEXT:    br label [[BB4]]
19; CHECK:       bb4:
20; CHECK-NEXT:    br i1 [[P]], label [[BB5:%.*]], label [[BB6:%.*]]
21; CHECK:       bb5:
22; CHECK-NEXT:    br i1 true, label [[BB7]], label [[BB7]]
23; CHECK:       bb6:
24; CHECK-NEXT:    br i1 true, label [[BB7]], label [[BB7]]
25; CHECK:       bb7:
26; CHECK-NEXT:    br i1 [[P]], label [[BB2]], label [[BB8:%.*]]
27; CHECK:       bb8:
28; CHECK-NEXT:    ret void
29;
30entry:
31  br label %bb2
32
33bb2:
34  %t1 = phi i64 [ 0, %entry ], [ %t5, %bb7 ]
35  %t2 = add i64 %t1, 1
36  %t3 = icmp ult i64 0, %t2
37  br i1 %t3, label %bb3, label %bb4
38
39bb3:
40  %t4 = call i64 @f()
41  br label %bb4
42
43bb4:
44  %foo = phi i64 [ %t4, %bb3 ], [ 0, %bb2 ]
45  br i1 %p, label %bb5, label %bb6
46
47bb5:
48  br i1 true, label %bb7, label %bb7
49
50bb6:
51  br i1 true, label %bb7, label %bb7
52
53bb7:
54  %t5 = add i64 %t1, 1
55  br i1 %p, label %bb2, label %bb8
56
57bb8:
58  ret void
59}
60
61declare i64 @f()
62