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
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes='simple-loop-unswitch<nontrivial>' -S < %s | FileCheck %s
; RUN: opt -passes='loop(simple-loop-unswitch<nontrivial>),verify<loops>' -S < %s | FileCheck %s
declare void @may_exit()
declare void @throw_npe()
; It is illegal to preserve make_implicit notion of the condition being
; unswitched because we may exit loop before we reach the condition, so
; there is no guarantee that following implicit branch always means getting
; to throw_npe block.
define i32 @test_should_drop_make_implicit(ptr %p1, ptr %p2) {
; CHECK-LABEL: @test_should_drop_make_implicit(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[P2:%.*]], null
; CHECK-NEXT: [[NULL_CHECK_FR:%.*]] = freeze i1 [[NULL_CHECK]]
; CHECK-NEXT: br i1 [[NULL_CHECK_FR]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]]
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: [[X_US:%.*]] = load i32, ptr [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND_US]], label [[SIDE_EXIT_SPLIT_US:%.*]], label [[NULL_CHECK_BLOCK_US:%.*]]
; CHECK: null_check_block.us:
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: side_exit.split.us:
; CHECK-NEXT: br label [[SIDE_EXIT:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P1]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND]], label [[SIDE_EXIT_SPLIT:%.*]], label [[NULL_CHECK_BLOCK:%.*]]
; CHECK: null_check_block:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: side_exit.split:
; CHECK-NEXT: br label [[SIDE_EXIT]]
; CHECK: side_exit:
; CHECK-NEXT: ret i32 0
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA2:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA2]]
;
entry:
%null_check = icmp eq ptr %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, ptr %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %side_exit_cond, label %side_exit, label %null_check_block
null_check_block:
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
side_exit:
ret i32 0
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here make.implicit notion may be preserved because we always get to throw_npe
; after following true branch. This is a trivial unswitch.
define i32 @test_may_keep_make_implicit_trivial(ptr %p1, ptr %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_trivial(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[THROW_NPE:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[SIDE_EXIT_BLOCK:%.*]]
; CHECK: side_exit_block:
; CHECK-NEXT: br i1 [[SIDE_EXIT_COND]], label [[SIDE_EXIT:%.*]], label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: side_exit:
; CHECK-NEXT: ret i32 0
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA2:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA2]]
;
entry:
%null_check = icmp eq ptr %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, ptr %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %side_exit_block, !make.implicit !0
side_exit_block:
br i1 %side_exit_cond, label %side_exit, label %backedge
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
side_exit:
ret i32 0
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
define i32 @test_may_keep_make_implicit_non_trivial(ptr %p1, ptr %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_non_trivial(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: [[X_US:%.*]] = load i32, ptr [[P1:%.*]], align 4
; CHECK-NEXT: [[INNER_BLOCK_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br i1 [[INNER_BLOCK_COND_US]], label [[INNER_BLOCK_US:%.*]], label [[NULL_CHECK_BLOCK_US:%.*]]
; CHECK: inner_block.us:
; CHECK-NEXT: br label [[NULL_CHECK_BLOCK_US]]
; CHECK: null_check_block.us:
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P1]], align 4
; CHECK-NEXT: [[INNER_BLOCK_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br i1 [[INNER_BLOCK_COND]], label [[INNER_BLOCK:%.*]], label [[NULL_CHECK_BLOCK:%.*]]
; CHECK: inner_block:
; CHECK-NEXT: br label [[NULL_CHECK_BLOCK]]
; CHECK: null_check_block:
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq ptr %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, ptr %p1
%inner_block_cond = icmp eq i32 %x, 0
br i1 %inner_block_cond, label %inner_block, label %null_check_block
inner_block:
br label %null_check_block
null_check_block:
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here make.implicit notion should be dropped because of exiting call.
define i32 @test_should_drop_make_implicit_exiting_call(ptr %p1, ptr %p2) {
; CHECK-LABEL: @test_should_drop_make_implicit_exiting_call(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[P2:%.*]], null
; CHECK-NEXT: [[NULL_CHECK_FR:%.*]] = freeze i1 [[NULL_CHECK]]
; CHECK-NEXT: br i1 [[NULL_CHECK_FR]], label [[ENTRY_SPLIT_US:%.*]], label [[ENTRY_SPLIT:%.*]]
; CHECK: entry.split.us:
; CHECK-NEXT: br label [[LOOP_US:%.*]]
; CHECK: loop.us:
; CHECK-NEXT: [[IV_US:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT_US]] ]
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: [[X_US:%.*]] = load i32, ptr [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND_US:%.*]] = icmp eq i32 [[X_US]], 0
; CHECK-NEXT: br label [[THROW_NPE_SPLIT_US:%.*]]
; CHECK: throw_npe.split.us:
; CHECK-NEXT: br label [[THROW_NPE:%.*]]
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P1]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq ptr %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
call void @may_exit()
%x = load i32, ptr %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
; Here exiting call goes after the null check, so make.implicit may be preserved.
define i32 @test_may_keep_make_implicit_exiting_call(ptr %p1, ptr %p2) {
; CHECK-LABEL: @test_may_keep_make_implicit_exiting_call(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq ptr [[P2:%.*]], null
; CHECK-NEXT: br i1 [[NULL_CHECK]], label [[THROW_NPE:%.*]], label [[ENTRY_SPLIT:%.*]], !make.implicit !0
; CHECK: entry.split:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY_SPLIT]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[X:%.*]] = load i32, ptr [[P1:%.*]], align 4
; CHECK-NEXT: [[SIDE_EXIT_COND:%.*]] = icmp eq i32 [[X]], 0
; CHECK-NEXT: br label [[BACKEDGE]]
; CHECK: backedge:
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = icmp slt i32 [[IV_NEXT]], 10000
; CHECK-NEXT: call void @may_exit()
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: throw_npe:
; CHECK-NEXT: call void @throw_npe()
; CHECK-NEXT: unreachable
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA1:%.*]] = phi i32 [ [[X]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA1]]
;
entry:
%null_check = icmp eq ptr %p2, null
br label %loop
loop:
%iv = phi i32 [0, %entry], [%iv.next, %backedge]
%x = load i32, ptr %p1
%side_exit_cond = icmp eq i32 %x, 0
br i1 %null_check, label %throw_npe, label %backedge, !make.implicit !0
backedge:
%iv.next = add i32 %iv,1
%loop_cond = icmp slt i32 %iv.next, 10000
call void @may_exit()
br i1 %loop_cond, label %loop, label %exit
throw_npe:
call void @throw_npe()
unreachable
exit:
ret i32 %x
}
!0 = !{}
|
