br-identical.ll
712 Bytes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
; RUN: opt -newgvn -S -o - %s | FileCheck %s
; RUN: opt -passes=newgvn -S -o - %s | FileCheck %s
; If a branch has two identical successors, we cannot declare either dead.
define void @widget(i1 %p) {
entry:
br label %bb2
bb2:
%t1 = phi i64 [ 0, %entry ], [ %t5, %bb7 ]
%t2 = add i64 %t1, 1
%t3 = icmp ult i64 0, %t2
br i1 %t3, label %bb3, label %bb4
bb3:
%t4 = call i64 @f()
br label %bb4
bb4:
; CHECK-NOT: phi {{.*}} undef
%foo = phi i64 [ %t4, %bb3 ], [ 0, %bb2 ]
br i1 %p, label %bb5, label %bb6
bb5:
br i1 true, label %bb7, label %bb7
bb6:
br i1 true, label %bb7, label %bb7
bb7:
%t5 = add i64 %t1, 1
br i1 %p, label %bb2, label %bb8
bb8:
ret void
}
declare i64 @f()