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1; RUN: opt -loop-unswitch -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s
2; RUN: opt -loop-unswitch -simplifycfg -S < %s | FileCheck %s
3; PR5373
4
5; Loop unswitching shouldn't trivially unswitch the true case of condition %a
6; in the code here because it leads to an infinite loop. While this doesn't
7; contain any instructions with side effects, it's still a kind of side effect.
8; It can trivially unswitch on the false cas of condition %a though.
9
10; STATS: 2 loop-unswitch - Number of branches unswitched
11; STATS: 1 loop-unswitch - Number of unswitches that are trivial
12
13; CHECK: @func_16
14; CHECK-NEXT: entry:
15; CHECK-NEXT: br i1 %a, label %entry.split, label %abort0.split
16
17; CHECK: entry.split:
18; CHECK-NEXT: br i1 %b, label %cond.end.us, label %abort1
19
20; CHECK: cond.end.us:
21; CHECK-NEXT: br label %cond.end.us
22
23; CHECK: abort0.split:
24; CHECK-NEXT: call void @end0() noreturn nounwind
25; CHECK-NEXT: unreachable
26
27; CHECK: abort1:
28; CHECK-NEXT: call void @end1() noreturn nounwind
29; CHECK-NEXT: unreachable
30
31; CHECK: }
32
33define void @func_16(i1 %a, i1 %b) nounwind {
34entry:
35  br label %for.body
36
37for.body:
38  br i1 %a, label %cond.end, label %abort0
39
40cond.end:
41  br i1 %b, label %for.body, label %abort1
42
43abort0:
44  call void @end0() noreturn nounwind
45  unreachable
46
47abort1:
48  call void @end1() noreturn nounwind
49  unreachable
50}
51
52declare void @end0() noreturn
53declare void @end1() noreturn
54