xref: /llvm-project/llvm/test/Transforms/SimplifyCFG/branch-cond-dont-merge.ll (revision b93ff3e5ce1ce0273c390ae5a3e829e89ee8292b)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
3
4declare void @bar()
5declare i1 @uniform_result(i1 %c)
6
7define void @dont_merge_cbranches1(i32 %V) {
8; CHECK-LABEL: @dont_merge_cbranches1(
9; CHECK-NEXT:    [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
10; CHECK-NEXT:    [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
11; CHECK-NEXT:    br i1 [[UNIFORM_COND]], label [[BB2:%.*]], label [[EXIT:%.*]], !prof [[PROF0:![0-9]+]]
12; CHECK:       bb2:
13; CHECK-NEXT:    br i1 [[DIVERGENT_COND]], label [[BB3:%.*]], label [[EXIT]]
14; CHECK:       bb3:
15; CHECK-NEXT:    call void @bar()
16; CHECK-NEXT:    br label [[EXIT]]
17; CHECK:       exit:
18; CHECK-NEXT:    ret void
19;
20  %divergent_cond = icmp ne i32 %V, 0
21  %uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
22  br i1 %uniform_cond, label %bb2, label %exit, !prof !0
23bb2:
24  br i1 %divergent_cond, label %bb3, label %exit
25bb3:
26  call void @bar( )
27  br label %exit
28exit:
29  ret void
30}
31
32define void @dont_merge_cbranches2(i32 %V) {
33; CHECK-LABEL: @dont_merge_cbranches2(
34; CHECK-NEXT:    [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
35; CHECK-NEXT:    [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
36; CHECK-NEXT:    br i1 [[UNIFORM_COND]], label [[EXIT:%.*]], label [[BB2:%.*]], !prof [[PROF1:![0-9]+]]
37; CHECK:       bb2:
38; CHECK-NEXT:    br i1 [[DIVERGENT_COND]], label [[BB3:%.*]], label [[EXIT]]
39; CHECK:       bb3:
40; CHECK-NEXT:    call void @bar()
41; CHECK-NEXT:    br label [[EXIT]]
42; CHECK:       exit:
43; CHECK-NEXT:    ret void
44;
45  %divergent_cond = icmp ne i32 %V, 0
46  %uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
47  br i1 %uniform_cond, label %exit, label %bb2, !prof !1
48bb2:
49  br i1 %divergent_cond, label %bb3, label %exit
50bb3:
51  call void @bar( )
52  br label %exit
53exit:
54  ret void
55}
56
57define void @merge_cbranches(i32 %V) {
58; CHECK-LABEL: @merge_cbranches(
59; CHECK-NEXT:    [[DIVERGENT_COND:%.*]] = icmp ne i32 [[V:%.*]], 0
60; CHECK-NEXT:    [[UNIFORM_COND:%.*]] = call i1 @uniform_result(i1 [[DIVERGENT_COND]])
61; CHECK-NEXT:    [[DIVERGENT_COND_NOT:%.*]] = xor i1 [[DIVERGENT_COND]], true
62; CHECK-NEXT:    [[BRMERGE:%.*]] = select i1 [[UNIFORM_COND]], i1 true, i1 [[DIVERGENT_COND_NOT]]
63; CHECK-NEXT:    br i1 [[BRMERGE]], label [[EXIT:%.*]], label [[BB3:%.*]], !prof [[PROF2:![0-9]+]]
64; CHECK:       bb3:
65; CHECK-NEXT:    call void @bar()
66; CHECK-NEXT:    br label [[EXIT]]
67; CHECK:       exit:
68; CHECK-NEXT:    ret void
69;
70  %divergent_cond = icmp ne i32 %V, 0
71  %uniform_cond = call i1 @uniform_result(i1 %divergent_cond)
72  br i1 %uniform_cond, label %exit, label %bb2, !prof !2
73bb2:
74  br i1 %divergent_cond, label %bb3, label %exit
75bb3:
76  call void @bar( )
77  br label %exit
78exit:
79  ret void
80}
81
82define void @uint32_overflow_test(i1 %arg, i1 %arg1) {
83; CHECK-LABEL: @uint32_overflow_test(
84; CHECK-NEXT:  bb:
85; CHECK-NEXT:    [[BRMERGE:%.*]] = select i1 [[ARG:%.*]], i1 true, i1 [[ARG1:%.*]]
86; CHECK-NEXT:    ret void
87;
88bb:
89  br i1 %arg, label %bb4, label %bb2, !prof !3
90
91bb2:
92  br i1 %arg1, label %bb4, label %bb3
93
94bb3:
95  br label %bb4
96
97bb4:
98  ret void
99}
100
101!0 = !{!"branch_weights", i32 1, i32 1000}
102!1 = !{!"branch_weights", i32 1000, i32 1}
103!2 = !{!"branch_weights", i32 3, i32 2}
104!3 = !{!"branch_weights", i32 -258677585, i32 -1212131848}
105