xref: /llvm-project/llvm/test/Transforms/JumpThreading/pr15851_hang.ll (revision 07e34d2de565a88da2724d52cdcf47b4bca873db)
1; RUN: opt -S -passes=jump-threading < %s | FileCheck %s
2
3; CHECK-LABEL: @f(
4; CHECK-LABEL: entry
5; CHECK-NEXT: ret void
6;
7; JumpThreading must detect the next two blocks are unreachable from entry
8; and leave them alone. A subsequent pass will remove them from @f.
9;
10; CHECK: for.cond1:
11; CHECK-NEXT: phi
12; CHECK-NEXT: icmp
13; CHECK-NEXT: br i1 %cmp, label %for.body, label %for.cond1
14; CHECK: for.body:
15; CHECK-NEXT: add
16; CHECK-NEXT: icmp
17; CHECK-NEXT: br i1 %a, label %for.cond1, label %for.cond1
18
19define void @f() {
20entry:
21  ret void
22
23for.cond1:
24  %i.025 = phi i32 [ %inc, %for.body ], [ %inc, %for.body ], [ 1, %for.cond1 ]
25  %cmp = icmp slt i32 %i.025, 2
26  br i1 %cmp, label %for.body, label %for.cond1
27
28for.body:
29  %inc = add nsw i32 %i.025, 0
30  %a = icmp ugt i32 %inc, 2
31  br i1 %a, label %for.cond1, label %for.cond1
32}
33