1; RUN: opt < %s -mtriple=x86_64-unknown-linux-gnu -instcombine -S | FileCheck %s
2; Checks that the select-icmp optimization is safe in two cases
3declare void @foo(i32)
4declare i32 @bar(i32)
5
6; don't replace 'cond' by 'len' in the home block ('bb') that
7; contains the select
8define void @test1(i32 %len) {
9entry:
10  br label %bb
11
12bb:
13  %cmp = icmp ult i32 %len, 8
14  %cond = select i1 %cmp, i32 %len, i32 8
15  call void @foo(i32 %cond)
16  %cmp11 = icmp eq i32 %cond, 8
17  br i1 %cmp11, label %for.end, label %bb
18
19for.end:
20  ret void
21; CHECK: select
22; CHECK: icmp eq i32 %cond, 8
23}
24
25; don't replace 'cond' by 'len' in a block ('b1') that dominates all uses
26; of the select outside the home block ('bb'), but can be reached from the home
27; block on another path ('bb -> b0 -> b1')
28define void @test2(i32 %len) {
29entry:
30  %0 = call i32 @bar(i32 %len);
31  %cmp = icmp ult i32 %len, 4
32  br i1 %cmp, label %bb, label %b1
33bb:
34  %cmp2 = icmp ult i32 %0, 2
35  %cond = select i1 %cmp2, i32 %len, i32 8
36  %cmp3 = icmp eq i32 %cond, 8
37  br i1 %cmp3, label %b0, label %b1
38
39b0:
40  call void @foo(i32 %len)
41  br label %b1
42
43b1:
44; CHECK: phi i32 [ %cond, %bb ], [ undef, %b0 ], [ %0, %entry ]
45  %1 = phi i32 [ %cond, %bb ], [ undef, %b0 ], [ %0, %entry ]
46  br label %ret
47
48ret:
49  call void @foo(i32 %1)
50  ret void
51}
52