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
|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -instsimplify < %s | FileCheck %s
declare void @bar(i8* %a, i8* nonnull noundef %b)
declare void @bar_without_noundef(i8* %a, i8* nonnull %b)
; 'y' must be nonnull.
define i1 @caller1(i8* %x, i8* %y) {
; CHECK-LABEL: @caller1(
; CHECK-NEXT: call void @bar(i8* [[X:%.*]], i8* [[Y:%.*]])
; CHECK-NEXT: ret i1 false
;
call void @bar(i8* %x, i8* %y)
%null_check = icmp eq i8* %y, null
ret i1 %null_check
}
; Don't know anything about 'y'.
define i1 @caller1_maybepoison(i8* %x, i8* %y) {
; CHECK-LABEL: @caller1_maybepoison(
; CHECK-NEXT: call void @bar_without_noundef(i8* [[X:%.*]], i8* [[Y:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[Y]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
call void @bar_without_noundef(i8* %x, i8* %y)
%null_check = icmp eq i8* %y, null
ret i1 %null_check
}
; Don't know anything about 'y'.
define i1 @caller2(i8* %x, i8* %y) {
; CHECK-LABEL: @caller2(
; CHECK-NEXT: call void @bar(i8* [[Y:%.*]], i8* [[X:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[Y]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
call void @bar(i8* %y, i8* %x)
%null_check = icmp eq i8* %y, null
ret i1 %null_check
}
; 'y' must be nonnull.
define i1 @caller3(i8* %x, i8* %y) {
; CHECK-LABEL: @caller3(
; CHECK-NEXT: call void @bar(i8* [[X:%.*]], i8* [[Y:%.*]])
; CHECK-NEXT: ret i1 true
;
call void @bar(i8* %x, i8* %y)
%null_check = icmp ne i8* %y, null
ret i1 %null_check
}
; FIXME: The call is guaranteed to execute, so 'y' must be nonnull throughout.
define i1 @caller4(i8* %x, i8* %y) {
; CHECK-LABEL: @caller4(
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp ne i8* [[Y:%.*]], null
; CHECK-NEXT: call void @bar(i8* [[X:%.*]], i8* [[Y]])
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%null_check = icmp ne i8* %y, null
call void @bar(i8* %x, i8* %y)
ret i1 %null_check
}
; The call to bar() does not dominate the null check, so no change.
define i1 @caller5(i8* %x, i8* %y) {
; CHECK-LABEL: @caller5(
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[Y:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[T:%.*]], label [[F:%.*]]
; CHECK: t:
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
; CHECK: f:
; CHECK-NEXT: call void @bar(i8* [[X:%.*]], i8* [[Y]])
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%null_check = icmp eq i8* %y, null
br i1 %null_check, label %t, label %f
t:
ret i1 %null_check
f:
call void @bar(i8* %x, i8* %y)
ret i1 %null_check
}
; Make sure that an invoke works similarly to a call.
declare i32 @esfp(...)
define i1 @caller6(i8* %x, i8* %y) personality i8* bitcast (i32 (...)* @esfp to i8*){
; CHECK-LABEL: @caller6(
; CHECK-NEXT: invoke void @bar(i8* [[X:%.*]], i8* nonnull [[Y:%.*]])
; CHECK-NEXT: to label [[CONT:%.*]] unwind label [[EXC:%.*]]
; CHECK: cont:
; CHECK-NEXT: ret i1 false
; CHECK: exc:
; CHECK-NEXT: [[LP:%.*]] = landingpad { i8*, i32 }
; CHECK-NEXT: filter [0 x i8*] zeroinitializer
; CHECK-NEXT: unreachable
;
invoke void @bar(i8* %x, i8* nonnull %y)
to label %cont unwind label %exc
cont:
%null_check = icmp eq i8* %y, null
ret i1 %null_check
exc:
%lp = landingpad { i8*, i32 }
filter [0 x i8*] zeroinitializer
unreachable
}
declare i8* @returningPtr(i8* returned %p)
define i1 @nonnullReturnTest(i8* nonnull %x) {
; CHECK-LABEL: @nonnullReturnTest(
; CHECK-NEXT: [[X2:%.*]] = call i8* @returningPtr(i8* [[X:%.*]])
; CHECK-NEXT: ret i1 false
;
%x2 = call i8* @returningPtr(i8* %x)
%null_check = icmp eq i8* %x2, null
ret i1 %null_check
}
define i1 @unknownReturnTest(i8* %x) {
; CHECK-LABEL: @unknownReturnTest(
; CHECK-NEXT: [[X2:%.*]] = call i8* @returningPtr(i8* [[X:%.*]])
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[X2]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%x2 = call i8* @returningPtr(i8* %x)
%null_check = icmp eq i8* %x2, null
ret i1 %null_check
}
; Make sure that if load/store happened, the pointer is nonnull.
define i32 @test_null_after_store(i32* %0) {
; CHECK-LABEL: @test_null_after_store(
; CHECK-NEXT: store i32 123, i32* [[TMP0:%.*]], align 4
; CHECK-NEXT: ret i32 2
;
store i32 123, i32* %0, align 4
%2 = icmp eq i32* %0, null
%3 = select i1 %2, i32 1, i32 2
ret i32 %3
}
define i32 @test_null_after_load(i32* %0) {
; CHECK-LABEL: @test_null_after_load(
; CHECK-NEXT: ret i32 1
;
%2 = load i32, i32* %0, align 4
%3 = icmp eq i32* %0, null
%4 = select i1 %3, i32 %2, i32 1
ret i32 %4
}
; Make sure that different address space does not affect null pointer check.
define i32 @test_null_after_store_addrspace(i32 addrspace(1)* %0) {
; CHECK-LABEL: @test_null_after_store_addrspace(
; CHECK-NEXT: store i32 123, i32 addrspace(1)* [[TMP0:%.*]], align 4
; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i32 addrspace(1)* [[TMP0]], null
; CHECK-NEXT: [[TMP3:%.*]] = select i1 [[TMP2]], i32 1, i32 2
; CHECK-NEXT: ret i32 [[TMP3]]
;
store i32 123, i32 addrspace(1)* %0, align 4
%2 = icmp eq i32 addrspace(1)* %0, null
%3 = select i1 %2, i32 1, i32 2
ret i32 %3
}
define i32 @test_null_after_load_addrspace(i32 addrspace(1)* %0) {
; CHECK-LABEL: @test_null_after_load_addrspace(
; CHECK-NEXT: [[TMP2:%.*]] = load i32, i32 addrspace(1)* [[TMP0:%.*]], align 4
; CHECK-NEXT: [[TMP3:%.*]] = icmp eq i32 addrspace(1)* [[TMP0]], null
; CHECK-NEXT: [[TMP4:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 1
; CHECK-NEXT: ret i32 [[TMP4]]
;
%2 = load i32, i32 addrspace(1)* %0, align 4
%3 = icmp eq i32 addrspace(1)* %0, null
%4 = select i1 %3, i32 %2, i32 1
ret i32 %4
}
; Make sure if store happened after the check, nullptr check is not removed.
declare i8* @func(i64)
define i8* @test_load_store_after_check(i8* %0) {
; CHECK-LABEL: @test_load_store_after_check(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP1:%.*]] = call i8* @func(i64 0)
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[TMP1]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[RETURN:%.*]], label [[IF_END:%.*]]
; CHECK: if.end:
; CHECK-NEXT: store i8 7, i8* [[TMP1]], align 1
; CHECK-NEXT: br label [[RETURN]]
; CHECK: return:
; CHECK-NEXT: [[RETVAL_0:%.*]] = phi i8* [ [[TMP1]], [[IF_END]] ], [ null, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i8* [[RETVAL_0]]
;
entry:
%1 = call i8* @func(i64 0)
%null_check = icmp eq i8* %1, null
br i1 %null_check, label %return, label %if.end
if.end:
store i8 7, i8* %1
br label %return
return:
%retval.0 = phi i8* [ %1, %if.end ], [ null, %entry ]
ret i8* %retval.0
}
|
