xref: /llvm-project/llvm/test/Transforms/SimplifyCFG/div-rem-pairs.ll (revision d1d129356909af2f6fefd6f1b9335a39fe172e9a)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S < %s | FileCheck %s
3
4; We could hoist the div/rem in these tests because it's safe to do so.
5; PR31028 - https://bugs.llvm.org/show_bug.cgi?id=31028
6; ...but since there's a separate pass for that, don't bother.
7
8define i32 @hoist_sdiv(i32 %a, i32 %b) {
9; CHECK-LABEL: @hoist_sdiv(
10; CHECK-NEXT:  entry:
11; CHECK-NEXT:    [[REM:%.*]] = srem i32 [[A:%.*]], [[B:%.*]]
12; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[REM]], 42
13; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
14; CHECK:       if:
15; CHECK-NEXT:    [[DIV:%.*]] = sdiv i32 [[A]], [[B]]
16; CHECK-NEXT:    br label [[END]]
17; CHECK:       end:
18; CHECK-NEXT:    [[RET:%.*]] = phi i32 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
19; CHECK-NEXT:    ret i32 [[RET]]
20;
21entry:
22  %rem = srem i32 %a, %b
23  %cmp = icmp eq i32 %rem, 42
24  br i1 %cmp, label %if, label %end
25
26if:
27  %div = sdiv i32 %a, %b
28  br label %end
29
30end:
31  %ret = phi i32 [ %div, %if ], [ 3, %entry ]
32  ret i32 %ret
33}
34
35define i64 @hoist_udiv(i64 %a, i64 %b) {
36; CHECK-LABEL: @hoist_udiv(
37; CHECK-NEXT:  entry:
38; CHECK-NEXT:    [[REM:%.*]] = urem i64 [[A:%.*]], [[B:%.*]]
39; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i64 [[REM]], 42
40; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
41; CHECK:       if:
42; CHECK-NEXT:    [[DIV:%.*]] = udiv i64 [[A]], [[B]]
43; CHECK-NEXT:    br label [[END]]
44; CHECK:       end:
45; CHECK-NEXT:    [[RET:%.*]] = phi i64 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
46; CHECK-NEXT:    ret i64 [[RET]]
47;
48entry:
49  %rem = urem i64 %a, %b
50  %cmp = icmp eq i64 %rem, 42
51  br i1 %cmp, label %if, label %end
52
53if:
54  %div = udiv i64 %a, %b
55  br label %end
56
57end:
58  %ret = phi i64 [ %div, %if ], [ 3, %entry ]
59  ret i64 %ret
60}
61
62define i16 @hoist_srem(i16 %a, i16 %b) {
63; CHECK-LABEL: @hoist_srem(
64; CHECK-NEXT:  entry:
65; CHECK-NEXT:    [[DIV:%.*]] = sdiv i16 [[A:%.*]], [[B:%.*]]
66; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i16 [[DIV]], 42
67; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
68; CHECK:       if:
69; CHECK-NEXT:    [[REM:%.*]] = srem i16 [[A]], [[B]]
70; CHECK-NEXT:    br label [[END]]
71; CHECK:       end:
72; CHECK-NEXT:    [[RET:%.*]] = phi i16 [ [[REM]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
73; CHECK-NEXT:    ret i16 [[RET]]
74;
75entry:
76  %div = sdiv i16 %a, %b
77  %cmp = icmp eq i16 %div, 42
78  br i1 %cmp, label %if, label %end
79
80if:
81  %rem = srem i16 %a, %b
82  br label %end
83
84end:
85  %ret = phi i16 [ %rem, %if ], [ 3, %entry ]
86  ret i16 %ret
87}
88
89define i8 @hoist_urem(i8 %a, i8 %b) {
90; CHECK-LABEL: @hoist_urem(
91; CHECK-NEXT:  entry:
92; CHECK-NEXT:    [[DIV:%.*]] = udiv i8 [[A:%.*]], [[B:%.*]]
93; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i8 [[DIV]], 42
94; CHECK-NEXT:    br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
95; CHECK:       if:
96; CHECK-NEXT:    [[REM:%.*]] = urem i8 [[A]], [[B]]
97; CHECK-NEXT:    br label [[END]]
98; CHECK:       end:
99; CHECK-NEXT:    [[RET:%.*]] = phi i8 [ [[REM]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
100; CHECK-NEXT:    ret i8 [[RET]]
101;
102entry:
103  %div = udiv i8 %a, %b
104  %cmp = icmp eq i8 %div, 42
105  br i1 %cmp, label %if, label %end
106
107if:
108  %rem = urem i8 %a, %b
109  br label %end
110
111end:
112  %ret = phi i8 [ %rem, %if ], [ 3, %entry ]
113  ret i8 %ret
114}
115
116