1; RUN: opt -S -licm < %s | FileCheck %s
2; RUN: opt -passes='require<aa>,require<targetir>,require<scalar-evolution>,loop(licm)' -S %s | FileCheck %s
3
4; UDiv is safe to speculate if the denominator is known non-zero.
5
6; CHECK-LABEL: @safe_udiv(
7; CHECK:      %div = udiv i64 %x, 2
8; CHECK-NEXT: br label %for.body
9
10define void @safe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
11entry:
12  br label %for.body
13
14for.body:                                         ; preds = %entry, %for.inc
15  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
16  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
17  %0 = load i32, i32* %arrayidx, align 4
18  %tobool = icmp eq i32 %0, 0
19  br i1 %tobool, label %for.inc, label %if.then
20
21if.then:                                          ; preds = %for.body
22  %div = udiv i64 %x, 2
23  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
24  store i64 %div, i64* %arrayidx1, align 8
25  br label %for.inc
26
27for.inc:                                          ; preds = %if.then, %for.body
28  %inc = add i64 %i.02, 1
29  %cmp = icmp slt i64 %inc, %n
30  br i1 %cmp, label %for.body, label %for.end
31
32for.end:                                          ; preds = %for.inc, %entry
33  ret void
34}
35
36; UDiv is unsafe to speculate if the denominator is not known non-zero.
37
38; CHECK-LABEL: @unsafe_udiv(
39; CHECK-NOT:  udiv
40; CHECK: for.body:
41
42define void @unsafe_udiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
43entry:
44  br label %for.body
45
46for.body:                                         ; preds = %entry, %for.inc
47  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
48  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
49  %0 = load i32, i32* %arrayidx, align 4
50  %tobool = icmp eq i32 %0, 0
51  br i1 %tobool, label %for.inc, label %if.then
52
53if.then:                                          ; preds = %for.body
54  %div = udiv i64 %x, %m
55  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
56  store i64 %div, i64* %arrayidx1, align 8
57  br label %for.inc
58
59for.inc:                                          ; preds = %if.then, %for.body
60  %inc = add i64 %i.02, 1
61  %cmp = icmp slt i64 %inc, %n
62  br i1 %cmp, label %for.body, label %for.end
63
64for.end:                                          ; preds = %for.inc, %entry
65  ret void
66}
67
68; SDiv is safe to speculate if the denominator is known non-zero and
69; known to have at least one zero bit.
70
71; CHECK-LABEL: @safe_sdiv(
72; CHECK:      %div = sdiv i64 %x, 2
73; CHECK-NEXT: br label %for.body
74
75define void @safe_sdiv(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
76entry:
77  %and = and i64 %m, -3
78  br label %for.body
79
80for.body:                                         ; preds = %entry, %for.inc
81  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
82  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
83  %0 = load i32, i32* %arrayidx, align 4
84  %tobool = icmp eq i32 %0, 0
85  br i1 %tobool, label %for.inc, label %if.then
86
87if.then:                                          ; preds = %for.body
88  %div = sdiv i64 %x, 2
89  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
90  store i64 %div, i64* %arrayidx1, align 8
91  br label %for.inc
92
93for.inc:                                          ; preds = %if.then, %for.body
94  %inc = add i64 %i.02, 1
95  %cmp = icmp slt i64 %inc, %n
96  br i1 %cmp, label %for.body, label %for.end
97
98for.end:                                          ; preds = %for.inc, %entry
99  ret void
100}
101
102; SDiv is unsafe to speculate if the denominator is not known non-zero.
103
104; CHECK-LABEL: @unsafe_sdiv_a(
105; CHECK-NOT:  sdiv
106; CHECK: for.body:
107
108define void @unsafe_sdiv_a(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
109entry:
110  %or = or i64 %m, 1
111  br label %for.body
112
113for.body:                                         ; preds = %entry, %for.inc
114  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
115  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
116  %0 = load i32, i32* %arrayidx, align 4
117  %tobool = icmp eq i32 %0, 0
118  br i1 %tobool, label %for.inc, label %if.then
119
120if.then:                                          ; preds = %for.body
121  %div = sdiv i64 %x, %or
122  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
123  store i64 %div, i64* %arrayidx1, align 8
124  br label %for.inc
125
126for.inc:                                          ; preds = %if.then, %for.body
127  %inc = add i64 %i.02, 1
128  %cmp = icmp slt i64 %inc, %n
129  br i1 %cmp, label %for.body, label %for.end
130
131for.end:                                          ; preds = %for.inc, %entry
132  ret void
133}
134
135; SDiv is unsafe to speculate if the denominator is not known to have a zero bit.
136
137; CHECK-LABEL: @unsafe_sdiv_b(
138; CHECK-NOT:  sdiv
139; CHECK: for.body:
140
141define void @unsafe_sdiv_b(i64 %x, i64 %m, i64 %n, i32* %p, i64* %q) nounwind {
142entry:
143  %and = and i64 %m, -3
144  br label %for.body
145
146for.body:                                         ; preds = %entry, %for.inc
147  %i.02 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
148  %arrayidx = getelementptr inbounds i32, i32* %p, i64 %i.02
149  %0 = load i32, i32* %arrayidx, align 4
150  %tobool = icmp eq i32 %0, 0
151  br i1 %tobool, label %for.inc, label %if.then
152
153if.then:                                          ; preds = %for.body
154  %div = sdiv i64 %x, %and
155  %arrayidx1 = getelementptr inbounds i64, i64* %q, i64 %i.02
156  store i64 %div, i64* %arrayidx1, align 8
157  br label %for.inc
158
159for.inc:                                          ; preds = %if.then, %for.body
160  %inc = add i64 %i.02, 1
161  %cmp = icmp slt i64 %inc, %n
162  br i1 %cmp, label %for.body, label %for.end
163
164for.end:                                          ; preds = %for.inc, %entry
165  ret void
166}
167
168; SDiv is unsafe to speculate inside an infinite loop.
169
170define void @unsafe_sdiv_c(i64 %a, i64 %b, i64* %p) {
171entry:
172; CHECK: entry:
173; CHECK-NOT: sdiv
174; CHECK: br label %for.body
175  br label %for.body
176
177for.body:
178  %c = icmp eq i64 %b, 0
179  br i1 %c, label %backedge, label %if.then
180
181if.then:
182  %d = sdiv i64 %a, %b
183  store i64 %d, i64* %p
184  br label %backedge
185
186backedge:
187  br label %for.body
188}
189