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
|
; RUN: opt -S -basic-aa -licm -licm-n2-threshold=0 -enable-mssa-loop-dependency=false %s | FileCheck %s
; RUN: opt -S -basic-aa -licm -licm-n2-threshold=0 -enable-mssa-loop-dependency=true -verify-memoryssa %s | FileCheck %s --check-prefix=ALIAS-N2
; RUN: opt -licm -basic-aa -licm-n2-threshold=200 < %s -S | FileCheck %s --check-prefix=ALIAS-N2
; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=0 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s
; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=0 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop-mssa(licm)' < %s -S | FileCheck %s --check-prefix=ALIAS-N2
; RUN: opt -aa-pipeline=basic-aa -licm-n2-threshold=200 -passes='require<aa>,require<targetir>,require<scalar-evolution>,require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck %s --check-prefix=ALIAS-N2
declare i32 @foo() readonly argmemonly nounwind
declare i32 @foo2() readonly nounwind
declare i32 @bar(i32* %loc2) readonly argmemonly nounwind
define void @test(i32* %loc) {
; CHECK-LABEL: @test
; CHECK: @foo
; CHECK-LABEL: loop:
; ALIAS-N2-LABEL: @test
; ALIAS-N2: @foo
; ALIAS-N2-LABEL: loop:
br label %loop
loop:
%res = call i32 @foo()
store i32 %res, i32* %loc
br label %loop
}
; Negative test: show argmemonly is required
define void @test_neg(i32* %loc) {
; CHECK-LABEL: @test_neg
; CHECK-LABEL: loop:
; CHECK: @foo
; ALIAS-N2-LABEL: @test_neg
; ALIAS-N2-LABEL: loop:
; ALIAS-N2: @foo
br label %loop
loop:
%res = call i32 @foo2()
store i32 %res, i32* %loc
br label %loop
}
define void @test2(i32* noalias %loc, i32* noalias %loc2) {
; CHECK-LABEL: @test2
; CHECK: @bar
; CHECK-LABEL: loop:
; ALIAS-N2-LABEL: @test2
; ALIAS-N2: @bar
; ALIAS-N2-LABEL: loop:
br label %loop
loop:
%res = call i32 @bar(i32* %loc2)
store i32 %res, i32* %loc
br label %loop
}
; Negative test: %might clobber gep
define void @test3(i32* %loc) {
; CHECK-LABEL: @test3
; CHECK-LABEL: loop:
; CHECK: @bar
; ALIAS-N2-LABEL: @test3
; ALIAS-N2-LABEL: loop:
; ALIAS-N2: @bar
br label %loop
loop:
%res = call i32 @bar(i32* %loc)
%gep = getelementptr i32, i32 *%loc, i64 1000000
store i32 %res, i32* %gep
br label %loop
}
; Negative test: %loc might alias %loc2
define void @test4(i32* %loc, i32* %loc2) {
; CHECK-LABEL: @test4
; CHECK-LABEL: loop:
; CHECK: @bar
; ALIAS-N2-LABEL: @test4
; ALIAS-N2-LABEL: loop:
; ALIAS-N2: @bar
br label %loop
loop:
%res = call i32 @bar(i32* %loc2)
store i32 %res, i32* %loc
br label %loop
}
declare i32 @foo_new(i32*) readonly
; With the default AST mechanism used by LICM for alias analysis,
; we clump foo_new with bar.
; With the N2 Alias analysis diagnostic tool, we are able to hoist the
; argmemonly bar call out of the loop.
; Using MemorySSA we can also hoist bar.
define void @test5(i32* %loc2, i32* noalias %loc) {
; ALIAS-N2-LABEL: @test5
; ALIAS-N2: @bar
; ALIAS-N2-LABEL: loop:
; CHECK-LABEL: @test5
; CHECK-LABEL: loop:
; CHECK: @bar
br label %loop
loop:
%res1 = call i32 @bar(i32* %loc2)
%res = call i32 @foo_new(i32* %loc2)
store volatile i32 %res1, i32* %loc
br label %loop
}
; memcpy doesn't write to it's source argument, so loads to that location
; can still be hoisted
define void @test6(i32* noalias %loc, i32* noalias %loc2) {
; CHECK-LABEL: @test6
; CHECK: %val = load i32, i32* %loc2
; CHECK-LABEL: loop:
; CHECK: @llvm.memcpy
; ALIAS-N2-LABEL: @test6
; ALIAS-N2: %val = load i32, i32* %loc2
; ALIAS-N2-LABEL: loop:
; ALIAS-N2: @llvm.memcpy
br label %loop
loop:
%val = load i32, i32* %loc2
store i32 %val, i32* %loc
%dest = bitcast i32* %loc to i8*
%src = bitcast i32* %loc2 to i8*
call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dest, i8* %src, i64 8, i1 false)
br label %loop
}
define void @test7(i32* noalias %loc, i32* noalias %loc2) {
; CHECK-LABEL: @test7
; CHECK: %val = load i32, i32* %loc2
; CHECK-LABEL: loop:
; CHECK: @custom_memcpy
; ALIAS-N2-LABEL: @test7
; ALIAS-N2: %val = load i32, i32* %loc2
; ALIAS-N2-LABEL: loop:
; ALIAS-N2: @custom_memcpy
br label %loop
loop:
%val = load i32, i32* %loc2
store i32 %val, i32* %loc
%dest = bitcast i32* %loc to i8*
%src = bitcast i32* %loc2 to i8*
call void @custom_memcpy(i8* %dest, i8* %src)
br label %loop
}
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i1)
declare void @custom_memcpy(i8* nocapture writeonly, i8* nocapture readonly) argmemonly nounwind
|
