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
| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt %s -instcombine -S | FileCheck %s
declare void @use8(i8)
declare void @use1(i1)
declare void @llvm.assume(i1)
define i1 @t0(i8 %base, i8 %offset) {
; CHECK-LABEL: @t0(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp ule i8 %adjusted, %base
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
; We need to produce extra instruction, so one of icmp's must go away.
define i1 @t1_oneuse0(i8 %base, i8 %offset) {
; CHECK-LABEL: @t1_oneuse0(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[NOT_NULL:%.*]] = icmp ne i8 [[ADJUSTED]], 0
; CHECK-NEXT: call void @use1(i1 [[NOT_NULL]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
call void @use1(i1 %not_null)
%no_underflow = icmp ule i8 %adjusted, %base
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
define i1 @t2_oneuse1(i8 %base, i8 %offset) {
; CHECK-LABEL: @t2_oneuse1(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[NO_UNDERFLOW:%.*]] = icmp ule i8 [[ADJUSTED]], [[BASE]]
; CHECK-NEXT: call void @use1(i1 [[NO_UNDERFLOW]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp ule i8 %adjusted, %base
call void @use1(i1 %no_underflow)
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
define i1 @n3_oneuse2_bad(i8 %base, i8 %offset) {
; CHECK-LABEL: @n3_oneuse2_bad(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[NOT_NULL:%.*]] = icmp ne i8 [[ADJUSTED]], 0
; CHECK-NEXT: call void @use1(i1 [[NOT_NULL]])
; CHECK-NEXT: [[NO_UNDERFLOW:%.*]] = icmp ule i8 [[ADJUSTED]], [[BASE]]
; CHECK-NEXT: call void @use1(i1 [[NO_UNDERFLOW]])
; CHECK-NEXT: [[R:%.*]] = and i1 [[NOT_NULL]], [[NO_UNDERFLOW]]
; CHECK-NEXT: ret i1 [[R]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
call void @use1(i1 %not_null)
%no_underflow = icmp ule i8 %adjusted, %base
call void @use1(i1 %no_underflow)
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
define i1 @t4_commutativity0(i8 %base, i8 %offset) {
; CHECK-LABEL: @t4_commutativity0(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp ule i8 %adjusted, %base
%r = and i1 %no_underflow, %not_null ; swapped
ret i1 %r
}
define i1 @t5_commutativity1(i8 %base, i8 %offset) {
; CHECK-LABEL: @t5_commutativity1(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp uge i8 %base, %adjusted ; swapped
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
define i1 @t6_commutativity3(i8 %base, i8 %offset) {
; CHECK-LABEL: @t6_commutativity3(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[OFFSET]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp uge i8 %base, %adjusted ; swapped
%r = and i1 %no_underflow, %not_null ; swapped
ret i1 %r
}
; We could have the opposite question, did we get null or overflow happened?
define i1 @t7(i8 %base, i8 %offset) {
; CHECK-LABEL: @t7(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = add i8 [[ADJUSTED]], -1
; CHECK-NEXT: [[TMP2:%.*]] = icmp uge i8 [[TMP1]], [[BASE]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp eq i8 %adjusted, 0
%no_underflow = icmp ugt i8 %adjusted, %base
%r = or i1 %not_null, %no_underflow
ret i1 %r
}
; The comparison can be with any of the values being added.
define i1 @t8(i8 %base, i8 %offset) {
; CHECK-LABEL: @t8(
; CHECK-NEXT: [[ADJUSTED:%.*]] = add i8 [[BASE:%.*]], [[OFFSET:%.*]]
; CHECK-NEXT: call void @use8(i8 [[ADJUSTED]])
; CHECK-NEXT: [[TMP1:%.*]] = sub i8 0, [[BASE]]
; CHECK-NEXT: [[TMP2:%.*]] = icmp ult i8 [[TMP1]], [[OFFSET]]
; CHECK-NEXT: ret i1 [[TMP2]]
;
%adjusted = add i8 %base, %offset
call void @use8(i8 %adjusted)
%not_null = icmp ne i8 %adjusted, 0
%no_underflow = icmp ule i8 %adjusted, %offset
%r = and i1 %not_null, %no_underflow
ret i1 %r
}
|