1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
| ; RUN: opt -objc-arc-contract -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64"
declare i8* @llvm.objc.retain(i8*)
declare void @llvm.objc.release(i8*)
declare void @use_pointer(i8*)
@x = external global i8*
; CHECK-LABEL: define void @test0(
; CHECK: entry:
; CHECK-NEXT: tail call void @llvm.objc.storeStrong(i8** @x, i8* %p) [[NUW:#[0-9]+]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test0(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Don't do this if the load is volatile.
; CHECK-LABEL: define void @test1(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load volatile i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test1(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load volatile i8*, i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Don't do this if the store is volatile.
; CHECK-LABEL: define void @test2(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: store volatile i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test2(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
store volatile i8* %0, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Don't do this if there's a use of the old pointer value between the store
; and the release.
; CHECK-LABEL: define void @test3(i8* %newValue) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @llvm.objc.retain(i8* %newValue) [[NUW]]
; CHECK-NEXT: %x1 = load i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %x0, i8** @x, align 8
; CHECK-NEXT: tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %x1) [[NUW]], !clang.imprecise_release !0
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test3(i8* %newValue) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
store i8* %newValue, i8** @x, align 8
tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
ret void
}
; Like test3, but with an icmp use instead of a call, for good measure.
; CHECK-LABEL: define i1 @test4(i8* %newValue, i8* %foo) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @llvm.objc.retain(i8* %newValue) [[NUW]]
; CHECK-NEXT: %x1 = load i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %x0, i8** @x, align 8
; CHECK-NEXT: %t = icmp eq i8* %x1, %foo
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %x1) [[NUW]], !clang.imprecise_release !0
; CHECK-NEXT: ret i1 %t
; CHECK-NEXT: }
define i1 @test4(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
store i8* %newValue, i8** @x, align 8
%t = icmp eq i8* %x1, %foo
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Do form an llvm.objc.storeStrong here, because the use is before the store.
; CHECK-LABEL: define i1 @test5(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @llvm.objc.storeStrong(i8** @x, i8* %newValue) [[NUW]]
; CHECK: }
define i1 @test5(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Like test5, but the release is before the store.
; CHECK-LABEL: define i1 @test6(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @llvm.objc.storeStrong(i8** @x, i8* %newValue) [[NUW]]
; CHECK: }
define i1 @test6(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
; Like test0, but there's no store, so don't form an llvm.objc.storeStrong.
; CHECK-LABEL: define void @test7(
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test7(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Like test0, but there's no retain, so don't form an llvm.objc.storeStrong.
; CHECK-LABEL: define void @test8(
; CHECK-NEXT: entry:
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %p, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test8(i8* %p) {
entry:
%tmp = load i8*, i8** @x, align 8
store i8* %p, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Make sure that we properly handle release that *may* release our new
; value in between the retain and the store. We need to be sure that
; this we can safely move the retain to the store. This specific test
; makes sure that we properly handled a release of an unrelated
; pointer.
;
; CHECK-LABEL: define i1 @test9(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK-NOT: llvm.objc.storeStrong
define i1 @test9(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
tail call void @llvm.objc.release(i8* %unrelated_ptr) nounwind, !clang.imprecise_release !0
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
; Make sure that we don't perform the optimization when we just have a call.
;
; CHECK-LABEL: define i1 @test10(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK-NOT: llvm.objc.storeStrong
define i1 @test10(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
call void @use_pointer(i8* %unrelated_ptr)
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
; Make sure we form the store strong if the use in between the retain
; and the store does not touch reference counts.
; CHECK-LABEL: define i1 @test11(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK: llvm.objc.storeStrong
define i1 @test11(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%t = icmp eq i8* %newValue, %foo
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
; Make sure that we form the store strong even if there are bitcasts on
; the pointers.
; CHECK-LABEL: define void @test12(
; CHECK: entry:
; CHECK-NEXT: %p16 = bitcast i8** @x to i16**
; CHECK-NEXT: %tmp16 = load i16*, i16** %p16, align 8
; CHECK-NEXT: %tmp8 = bitcast i16* %tmp16 to i8*
; CHECK-NEXT: %p32 = bitcast i8** @x to i32**
; CHECK-NEXT: %v32 = bitcast i8* %p to i32*
; CHECK-NEXT: %0 = bitcast i16** %p16 to i8**
; CHECK-NEXT: tail call void @llvm.objc.storeStrong(i8** %0, i8* %p)
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test12(i8* %p) {
entry:
%retain = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%p16 = bitcast i8** @x to i16**
%tmp16 = load i16*, i16** %p16, align 8
%tmp8 = bitcast i16* %tmp16 to i8*
%p32 = bitcast i8** @x to i32**
%v32 = bitcast i8* %retain to i32*
store i32* %v32, i32** %p32, align 8
tail call void @llvm.objc.release(i8* %tmp8) nounwind
ret void
}
; This used to crash.
; CHECK-LABEL: define i8* @test13(
; CHECK: tail call void @llvm.objc.storeStrong(i8** %{{.*}}, i8* %[[NEW:.*]])
; CHECK-NEXT: ret i8* %[[NEW]]
define i8* @test13(i8* %a0, i8* %a1, i8** %addr, i8* %new) {
%old = load i8*, i8** %addr, align 8
call void @llvm.objc.release(i8* %old)
%retained = call i8* @llvm.objc.retain(i8* %new)
store i8* %retained, i8** %addr, align 8
ret i8* %retained
}
!0 = !{}
; CHECK: attributes [[NUW]] = { nounwind }
|