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1; RUN: llc -mtriple=x86_64 -o - %s | FileCheck %s
2
3define i1 @try_cmpxchg(i32* %addr, i32 %desired, i32 %new) {
4; CHECK-LABEL: try_cmpxchg:
5; CHECK: cmpxchgl
6; CHECK-NOT: cmp
7; CHECK: sete %al
8; CHECK: retq
9  %pair = cmpxchg i32* %addr, i32 %desired, i32 %new seq_cst seq_cst
10  %success = extractvalue { i32, i1 } %pair, 1
11  ret i1 %success
12}
13
14define void @cmpxchg_flow(i64* %addr, i64 %desired, i64 %new) {
15; CHECK-LABEL: cmpxchg_flow:
16; CHECK: cmpxchgq
17; CHECK-NOT: cmp
18; CHECK-NOT: set
19; CHECK: {{jne|jeq}}
20  %pair = cmpxchg i64* %addr, i64 %desired, i64 %new seq_cst seq_cst
21  %success = extractvalue { i64, i1 } %pair, 1
22  br i1 %success, label %true, label %false
23
24true:
25  call void @foo()
26  ret void
27
28false:
29  call void @bar()
30  ret void
31}
32
33define i64 @cmpxchg_sext(i32* %addr, i32 %desired, i32 %new) {
34; CHECK-LABEL: cmpxchg_sext:
35; CHECK-DAG: cmpxchgl
36; CHECK-NOT: cmpl
37; CHECK: sete %al
38; CHECK: retq
39  %pair = cmpxchg i32* %addr, i32 %desired, i32 %new seq_cst seq_cst
40  %success = extractvalue { i32, i1 } %pair, 1
41  %mask = sext i1 %success to i64
42  ret i64 %mask
43}
44
45define i32 @cmpxchg_zext(i32* %addr, i32 %desired, i32 %new) {
46; CHECK-LABEL: cmpxchg_zext:
47; CHECK: cmpxchgl
48; CHECK-NOT: cmp
49; CHECK: sete [[BYTE:%[a-z0-9]+]]
50; CHECK: movzbl [[BYTE]], %eax
51  %pair = cmpxchg i32* %addr, i32 %desired, i32 %new seq_cst seq_cst
52  %success = extractvalue { i32, i1 } %pair, 1
53  %mask = zext i1 %success to i32
54  ret i32 %mask
55}
56
57
58define i32 @cmpxchg_use_eflags_and_val(i32* %addr, i32 %offset) {
59; CHECK-LABEL: cmpxchg_use_eflags_and_val:
60; CHECK: movl (%rdi), %e[[OLDVAL:[a-z0-9]+]]
61
62; CHECK: [[LOOPBB:.?LBB[0-9]+_[0-9]+]]:
63; CHECK: leal (%r[[OLDVAL]],%rsi), [[NEW:%[a-z0-9]+]]
64; CHECK: cmpxchgl [[NEW]], (%rdi)
65; CHECK-NOT: cmpl
66; CHECK: jne [[LOOPBB]]
67
68  ; Result already in %eax
69; CHECK: retq
70entry:
71  %init = load atomic i32* %addr seq_cst, align 4
72  br label %loop
73
74loop:
75  %old = phi i32 [%init, %entry], [%oldval, %loop]
76  %new = add i32 %old, %offset
77  %pair = cmpxchg i32* %addr, i32 %old, i32 %new seq_cst seq_cst
78  %oldval = extractvalue { i32, i1 } %pair, 0
79  %success = extractvalue { i32, i1 } %pair, 1
80  br i1 %success, label %done, label %loop
81
82done:
83  ret i32 %oldval
84}
85
86declare void @foo()
87declare void @bar()
88