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
|
; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
; RUN: opt -disable-output "-passes=print<scalar-evolution>" %s 2>&1 | FileCheck %s
; If m is constant, exact-not-taken is umin(n, m)
; https://alive2.llvm.org/ce/z/ZTNXgY
define void @logical_and_m_const(i32 %n) {
; CHECK-LABEL: 'logical_and_m_const'
; CHECK-NEXT: Classifying expressions for: @logical_and_m_const
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,3) S: [0,3) Exits: (2 umin %n) LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,4) S: [1,4) Exits: (1 + (2 umin %n))<nuw><nsw> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 %cond_i2, i1 false
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_and_m_const
; CHECK-NEXT: Loop %loop: backedge-taken count is (2 umin %n)
; CHECK-NEXT: Loop %loop: max backedge-taken count is 2
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is (2 umin %n)
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp ult i32 %i, %n
%cond_i2 = icmp ult i32 %i, 2
%cond = select i1 %cond_i, i1 %cond_i2, i1 false
br i1 %cond, label %loop, label %exit
exit:
ret void
}
; exact-not-taken is umin(2, m) because m participates in the exit branch condition.
; https://alive2.llvm.org/ce/z/rCVMmp
define void @logical_and_nonzero(i32 %m) {
; CHECK-LABEL: 'logical_and_nonzero'
; CHECK-NEXT: Classifying expressions for: @logical_and_nonzero
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,3) S: [0,3) Exits: (2 umin %m) LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,4) S: [1,4) Exits: (1 + (2 umin %m))<nuw><nsw> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 %cond_i2, i1 false
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_and_nonzero
; CHECK-NEXT: Loop %loop: backedge-taken count is (2 umin %m)
; CHECK-NEXT: Loop %loop: max backedge-taken count is 2
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is (2 umin %m)
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp ult i32 %i, 2
%cond_i2 = icmp ult i32 %i, %m
%cond = select i1 %cond_i, i1 %cond_i2, i1 false
br i1 %cond, label %loop, label %exit
exit:
ret void
}
; exact-not-taken cannot be umin(0, m) because m never participates in the exit branch condition.
; https://alive2.llvm.org/ce/z/rlaN4a
; Instead, it should be just 0.
define void @logical_and_zero(i32 %m) {
; CHECK-LABEL: 'logical_and_zero'
; CHECK-NEXT: Classifying expressions for: @logical_and_zero
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,1) S: [0,1) Exits: 0 LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,2) S: [1,2) Exits: 1 LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 %cond_i2, i1 false
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_and_zero
; CHECK-NEXT: Loop %loop: backedge-taken count is 0
; CHECK-NEXT: Loop %loop: max backedge-taken count is 0
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is 0
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp ult i32 %i, 0
%cond_i2 = icmp ult i32 %i, %m
%cond = select i1 %cond_i, i1 %cond_i2, i1 false
br i1 %cond, label %loop, label %exit
exit:
ret void
}
; exact-not-taken is umax(n, m) because both conditions (cond_i, cond_i2) participate in branching,
; preventing them from being poison.
; https://alive2.llvm.org/ce/z/8_p-zu
; Currently SCEV is conservative in this case and simply returns unknown.
define void @logical_and_inversed(i32 %n, i32 %m) {
; CHECK-LABEL: 'logical_and_inversed'
; CHECK-NEXT: Classifying expressions for: @logical_and_inversed
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 %cond_i2, i1 false
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_and_inversed
; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable max backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable predicated backedge-taken count.
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp uge i32 %i, %n
%cond_i2 = icmp uge i32 %i, %m
%cond = select i1 %cond_i, i1 %cond_i2, i1 false
br i1 %cond, label %exit, label %loop
exit:
ret void
}
; If m is constant, exact-not-taken is umin(n, m)
; https://alive2.llvm.org/ce/z/RQmJiq
define void @logical_or_m_const(i32 %n) {
; CHECK-LABEL: 'logical_or_m_const'
; CHECK-NEXT: Classifying expressions for: @logical_or_m_const
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,3) S: [0,3) Exits: (2 umin %n) LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,4) S: [1,4) Exits: (1 + (2 umin %n))<nuw><nsw> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 true, i1 %cond_i2
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_or_m_const
; CHECK-NEXT: Loop %loop: backedge-taken count is (2 umin %n)
; CHECK-NEXT: Loop %loop: max backedge-taken count is 2
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is (2 umin %n)
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp uge i32 %i, %n
%cond_i2 = icmp uge i32 %i, 2
%cond = select i1 %cond_i, i1 true, i1 %cond_i2
br i1 %cond, label %exit, label %loop
exit:
ret void
}
; exact-not-taken is umin(2, m) because m participates in exit branch condition.
; https://alive2.llvm.org/ce/z/zcHS_d
define void @logical_or_nonzero(i32 %m) {
; CHECK-LABEL: 'logical_or_nonzero'
; CHECK-NEXT: Classifying expressions for: @logical_or_nonzero
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,3) S: [0,3) Exits: (2 umin %m) LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,4) S: [1,4) Exits: (1 + (2 umin %m))<nuw><nsw> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 true, i1 %cond_i2
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_or_nonzero
; CHECK-NEXT: Loop %loop: backedge-taken count is (2 umin %m)
; CHECK-NEXT: Loop %loop: max backedge-taken count is 2
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is (2 umin %m)
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp uge i32 %i, 2
%cond_i2 = icmp uge i32 %i, %m
%cond = select i1 %cond_i, i1 true, i1 %cond_i2
br i1 %cond, label %exit, label %loop
exit:
ret void
}
; exact-not-taken cannot be umin(0, m) because m does not participate in exit branch condition.
; https://alive2.llvm.org/ce/z/-dUmmc
; Instead, exact-not-taken should be just 0.
define void @logical_or_zero(i32 %m) {
; CHECK-LABEL: 'logical_or_zero'
; CHECK-NEXT: Classifying expressions for: @logical_or_zero
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: [0,1) S: [0,1) Exits: 0 LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: [1,2) S: [1,2) Exits: 1 LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 true, i1 %cond_i2
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_or_zero
; CHECK-NEXT: Loop %loop: backedge-taken count is 0
; CHECK-NEXT: Loop %loop: max backedge-taken count is 0
; CHECK-NEXT: Loop %loop: Predicated backedge-taken count is 0
; CHECK-NEXT: Predicates:
; CHECK: Loop %loop: Trip multiple is 1
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp uge i32 %i, 0
%cond_i2 = icmp uge i32 %i, %m
%cond = select i1 %cond_i, i1 true, i1 %cond_i2
br i1 %cond, label %exit, label %loop
exit:
ret void
}
; exact-not-taken is umax(n, m) because both conditions (cond_i, cond_i2) participate in branching,
; preventing them from being poison.
; https://alive2.llvm.org/ce/z/VaCu9C
; Currently SCEV is conservative in this case and simply returns unknown.
define void @logical_or_inversed(i32 %n, i32 %m) {
; CHECK-LABEL: 'logical_or_inversed'
; CHECK-NEXT: Classifying expressions for: @logical_or_inversed
; CHECK-NEXT: %i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; CHECK-NEXT: --> {0,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %i.next = add i32 %i, 1
; CHECK-NEXT: --> {1,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
; CHECK-NEXT: %cond = select i1 %cond_i, i1 true, i1 %cond_i2
; CHECK-NEXT: --> %cond U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
; CHECK-NEXT: Determining loop execution counts for: @logical_or_inversed
; CHECK-NEXT: Loop %loop: Unpredictable backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable max backedge-taken count.
; CHECK-NEXT: Loop %loop: Unpredictable predicated backedge-taken count.
;
entry:
br label %loop
loop:
%i = phi i32 [0, %entry], [%i.next, %loop]
%i.next = add i32 %i, 1
%cond_i = icmp ult i32 %i, %n
%cond_i2 = icmp ult i32 %i, %m
%cond = select i1 %cond_i, i1 true, i1 %cond_i2
br i1 %cond, label %loop, label %exit
exit:
ret void
}
|
