• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1; RUN: opt -passes='loop(unswitch),verify<loops>' -S < %s | FileCheck %s
2; RUN: opt -verify-memoryssa -passes='loop-mssa(unswitch),verify<loops>' -S < %s | FileCheck %s
3
4define i32 @test(i32* %A, i1 %C) {
5entry:
6	br label %no_exit
7no_exit:		; preds = %no_exit.backedge, %entry
8	%i.0.0 = phi i32 [ 0, %entry ], [ %i.0.0.be, %no_exit.backedge ]		; <i32> [#uses=3]
9	%gep.upgrd.1 = zext i32 %i.0.0 to i64		; <i64> [#uses=1]
10	%tmp.7 = getelementptr i32, i32* %A, i64 %gep.upgrd.1		; <i32*> [#uses=4]
11	%tmp.13 = load i32, i32* %tmp.7		; <i32> [#uses=2]
12	%tmp.14 = add i32 %tmp.13, 1		; <i32> [#uses=1]
13	store i32 %tmp.14, i32* %tmp.7
14	br i1 %C, label %then, label %endif
15then:		; preds = %no_exit
16	%tmp.29 = load i32, i32* %tmp.7		; <i32> [#uses=1]
17	%tmp.30 = add i32 %tmp.29, 2		; <i32> [#uses=1]
18	store i32 %tmp.30, i32* %tmp.7
19	%inc9 = add i32 %i.0.0, 1		; <i32> [#uses=2]
20	%tmp.112 = icmp ult i32 %inc9, 100000		; <i1> [#uses=1]
21	br i1 %tmp.112, label %no_exit.backedge, label %return
22no_exit.backedge:		; preds = %endif, %then
23	%i.0.0.be = phi i32 [ %inc9, %then ], [ %inc, %endif ]		; <i32> [#uses=1]
24	br label %no_exit
25endif:		; preds = %no_exit
26	%inc = add i32 %i.0.0, 1		; <i32> [#uses=2]
27	%tmp.1 = icmp ult i32 %inc, 100000		; <i1> [#uses=1]
28	br i1 %tmp.1, label %no_exit.backedge, label %return
29return:		; preds = %endif, %then
30	ret i32 %tmp.13
31}
32
33; This simple test would normally unswitch, but should be inhibited by the presence of
34; the noduplicate call.
35
36; CHECK-LABEL: @test2(
37define i32 @test2(i32* %var) {
38  %mem = alloca i32
39  store i32 2, i32* %mem
40  %c = load i32, i32* %mem
41
42  br label %loop_begin
43
44loop_begin:
45
46  %var_val = load i32, i32* %var
47
48  switch i32 %c, label %default [
49      i32 1, label %inc
50      i32 2, label %dec
51  ]
52
53inc:
54  call void @incf() noreturn nounwind
55  br label %loop_begin
56dec:
57; CHECK: call void @decf()
58; CHECK-NOT: call void @decf()
59  call void @decf() noreturn nounwind noduplicate
60  br label %loop_begin
61default:
62  br label %loop_exit
63loop_exit:
64  ret i32 0
65; CHECK: }
66}
67
68; This simple test would normally unswitch, but should be inhibited by the presence of
69; the convergent call that is not control-dependent on the unswitch condition.
70
71; CHECK-LABEL: @test3(
72define i32 @test3(i32* %var) {
73  %mem = alloca i32
74  store i32 2, i32* %mem
75  %c = load i32, i32* %mem
76
77  br label %loop_begin
78
79loop_begin:
80
81  %var_val = load i32, i32* %var
82
83; CHECK: call void @conv()
84; CHECK-NOT: call void @conv()
85  call void @conv() convergent
86
87  switch i32 %c, label %default [
88      i32 1, label %inc
89      i32 2, label %dec
90  ]
91
92inc:
93  call void @incf() noreturn nounwind
94  br label %loop_begin
95dec:
96  call void @decf() noreturn nounwind
97  br label %loop_begin
98default:
99  br label %loop_exit
100loop_exit:
101  ret i32 0
102; CHECK: }
103}
104
105; Make sure we don't unswitch, as we can not find an input value %a
106; that will effectively unswitch 0 or 3 out of the loop.
107;
108; CHECK: define void @and_or_i2_as_switch_input(i2
109; CHECK: entry:
110; This is an indication that the loop has NOT been unswitched.
111; CHECK-NOT: icmp
112; CHECK: br
113define void @and_or_i2_as_switch_input(i2 %a) {
114entry:
115  br label %for.body
116
117for.body:
118  %i = phi i2 [ 0, %entry ], [ %inc, %for.inc ]
119  %and = and i2 %a, %i
120  %or = or i2 %and, %i
121  switch i2 %or, label %sw.default [
122    i2 0, label %sw.bb
123    i2 3, label %sw.bb1
124  ]
125
126sw.bb:
127  br label %sw.epilog
128
129sw.bb1:
130  br label %sw.epilog
131
132sw.default:
133  br label %sw.epilog
134
135sw.epilog:
136  br label %for.inc
137
138for.inc:
139  %inc = add nsw i2 %i, 1
140  %cmp = icmp slt i2 %inc, 3
141  br i1 %cmp, label %for.body, label %for.end
142
143for.end:
144  ret void
145}
146
147; Make sure we don't unswitch, as we can not find an input value %a
148; that will effectively unswitch true/false out of the loop.
149;
150; CHECK: define void @and_or_i1_as_branch_input(i1
151; CHECK: entry:
152; This is an indication that the loop has NOT been unswitched.
153; CHECK-NOT: icmp
154; CHECK: br
155define void @and_or_i1_as_branch_input(i1 %a) {
156entry:
157  br label %for.body
158
159for.body:
160  %i = phi i1 [ 0, %entry ], [ %inc, %for.inc ]
161  %and = and i1 %a, %i
162  %or = or i1 %and, %i
163  br i1 %or, label %sw.bb, label %sw.bb1
164
165sw.bb:
166  br label %sw.epilog
167
168sw.bb1:
169  br label %sw.epilog
170
171sw.epilog:
172  br label %for.inc
173
174for.inc:
175  %inc = add nsw i1 %i, 1
176  %cmp = icmp slt i1 %inc, 1
177  br i1 %cmp, label %for.body, label %for.end
178
179for.end:
180  ret void
181}
182
183declare void @incf() noreturn
184declare void @decf() noreturn
185declare void @conv() convergent
186