1; RUN: opt < %s -S -basicaa -licm | FileCheck %s
2
3; Check that we can hoist unordered loads
4define i32 @test1(i32* nocapture %y) nounwind uwtable ssp {
5entry:
6  br label %loop
7
8loop:
9  %i = phi i32 [ %inc, %loop ], [ 0, %entry ]
10  %val = load atomic i32, i32* %y unordered, align 4
11  %inc = add nsw i32 %i, 1
12  %exitcond = icmp eq i32 %inc, %val
13  br i1 %exitcond, label %end, label %loop
14
15end:
16  ret i32 %val
17; CHECK-LABEL: define i32 @test1(
18; CHECK: load atomic
19; CHECK-NEXT: br label %loop
20}
21
22; Check that we don't sink/hoist monotonic loads
23; (Strictly speaking, it's not forbidden, but it's supposed to be possible to
24; use monotonic for spinlock-like constructs.)
25define i32 @test2(i32* nocapture %y) nounwind uwtable ssp {
26entry:
27  br label %loop
28
29loop:
30  %val = load atomic i32, i32* %y monotonic, align 4
31  %exitcond = icmp ne i32 %val, 0
32  br i1 %exitcond, label %end, label %loop
33
34end:
35  ret i32 %val
36; CHECK-LABEL: define i32 @test2(
37; CHECK: load atomic
38; CHECK-NEXT: %exitcond = icmp ne
39; CHECK-NEXT: br i1 %exitcond, label %end, label %loop
40}
41
42; Check that we hoist unordered around monotonic.
43; (The noalias shouldn't be necessary in theory, but LICM isn't quite that
44; smart yet.)
45define i32 @test3(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
46entry:
47  br label %loop
48
49loop:
50  %vala = load atomic i32, i32* %y monotonic, align 4
51  %valb = load atomic i32, i32* %x unordered, align 4
52  %exitcond = icmp ne i32 %vala, %valb
53  br i1 %exitcond, label %end, label %loop
54
55end:
56  ret i32 %vala
57; CHECK-LABEL: define i32 @test3(
58; CHECK: load atomic i32, i32* %x unordered
59; CHECK-NEXT: br label %loop
60}
61
62; Don't try to "sink" unordered stores yet; it is legal, but the machinery
63; isn't there.
64define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
65entry:
66  br label %loop
67
68loop:
69  %vala = load atomic i32, i32* %y monotonic, align 4
70  store atomic i32 %vala, i32* %x unordered, align 4
71  %exitcond = icmp ne i32 %vala, 0
72  br i1 %exitcond, label %end, label %loop
73
74end:
75  ret i32 %vala
76; CHECK-LABEL: define i32 @test4(
77; CHECK: load atomic i32, i32* %y monotonic
78; CHECK-NEXT: store atomic
79}
80