1; RUN: opt -gvn -S < %s | FileCheck %s
2
3define i32 @f1(i32 %x) {
4  ; CHECK-LABEL: define i32 @f1(
5bb0:
6  %cmp = icmp eq i32 %x, 0
7  br i1 %cmp, label %bb2, label %bb1
8bb1:
9  br label %bb2
10bb2:
11  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
12  %foo = add i32 %cond, %x
13  ret i32 %foo
14  ; CHECK: bb2:
15  ; CHECK: ret i32 %x
16}
17
18define i32 @f2(i32 %x) {
19  ; CHECK-LABEL: define i32 @f2(
20bb0:
21  %cmp = icmp ne i32 %x, 0
22  br i1 %cmp, label %bb1, label %bb2
23bb1:
24  br label %bb2
25bb2:
26  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
27  %foo = add i32 %cond, %x
28  ret i32 %foo
29  ; CHECK: bb2:
30  ; CHECK: ret i32 %x
31}
32
33define i32 @f3(i32 %x) {
34  ; CHECK-LABEL: define i32 @f3(
35bb0:
36  switch i32 %x, label %bb1 [ i32 0, label %bb2]
37bb1:
38  br label %bb2
39bb2:
40  %cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
41  %foo = add i32 %cond, %x
42  ret i32 %foo
43  ; CHECK: bb2:
44  ; CHECK: ret i32 %x
45}
46
47declare void @g(i1)
48define void @f4(i8 * %x)  {
49; CHECK-LABEL: define void @f4(
50bb0:
51  %y = icmp eq i8* null, %x
52  br i1 %y, label %bb2, label %bb1
53bb1:
54  br label %bb2
55bb2:
56  %zed = icmp eq i8* null, %x
57  call void @g(i1 %zed)
58; CHECK: call void @g(i1 %y)
59  ret void
60}
61
62define double @fcmp_oeq_not_zero(double %x, double %y) {
63entry:
64  %cmp = fcmp oeq double %y, 2.0
65  br i1 %cmp, label %if, label %return
66
67if:
68  %div = fdiv double %x, %y
69  br label %return
70
71return:
72  %retval = phi double [ %div, %if ], [ %x, %entry ]
73  ret double %retval
74
75; CHECK-LABEL: define double @fcmp_oeq_not_zero(
76; CHECK: %div = fdiv double %x, 2.0
77}
78
79define double @fcmp_une_not_zero(double %x, double %y) {
80entry:
81  %cmp = fcmp une double %y, 2.0
82  br i1 %cmp, label %return, label %else
83
84else:
85  %div = fdiv double %x, %y
86  br label %return
87
88return:
89  %retval = phi double [ %div, %else ], [ %x, %entry ]
90  ret double %retval
91
92; CHECK-LABEL: define double @fcmp_une_not_zero(
93; CHECK: %div = fdiv double %x, 2.0
94}
95
96; PR22376 - We can't propagate zero constants because -0.0
97; compares equal to 0.0. If %y is -0.0 in this test case,
98; we would produce the wrong sign on the infinity return value.
99define double @fcmp_oeq_zero(double %x, double %y) {
100entry:
101  %cmp = fcmp oeq double %y, 0.0
102  br i1 %cmp, label %if, label %return
103
104if:
105  %div = fdiv double %x, %y
106  br label %return
107
108return:
109  %retval = phi double [ %div, %if ], [ %x, %entry ]
110  ret double %retval
111
112; CHECK-LABEL: define double @fcmp_oeq_zero(
113; CHECK: %div = fdiv double %x, %y
114}
115
116define double @fcmp_une_zero(double %x, double %y) {
117entry:
118  %cmp = fcmp une double %y, -0.0
119  br i1 %cmp, label %return, label %else
120
121else:
122  %div = fdiv double %x, %y
123  br label %return
124
125return:
126  %retval = phi double [ %div, %else ], [ %x, %entry ]
127  ret double %retval
128
129; CHECK-LABEL: define double @fcmp_une_zero(
130; CHECK: %div = fdiv double %x, %y
131}
132
133; We also cannot propagate a value if it's not a constant.
134; This is because the value could be 0.0 or -0.0.
135
136define double @fcmp_oeq_maybe_zero(double %x, double %y, double %z1, double %z2) {
137entry:
138 %z = fadd double %z1, %z2
139 %cmp = fcmp oeq double %y, %z
140 br i1 %cmp, label %if, label %return
141
142if:
143 %div = fdiv double %x, %z
144 br label %return
145
146return:
147 %retval = phi double [ %div, %if ], [ %x, %entry ]
148 ret double %retval
149
150; CHECK-LABEL: define double @fcmp_oeq_maybe_zero(
151; CHECK: %div = fdiv double %x, %z
152}
153
154define double @fcmp_une_maybe_zero(double %x, double %y, double %z1, double %z2) {
155entry:
156 %z = fadd double %z1, %z2
157 %cmp = fcmp une double %y, %z
158 br i1 %cmp, label %return, label %else
159
160else:
161 %div = fdiv double %x, %z
162 br label %return
163
164return:
165 %retval = phi double [ %div, %else ], [ %x, %entry ]
166 ret double %retval
167
168; CHECK-LABEL: define double @fcmp_une_maybe_zero(
169; CHECK: %div = fdiv double %x, %z
170}
171