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
| ; Test for a subtle bug when computing analyses during inlining and mutating
; the SCC structure. Without care, this can fail to invalidate analyses.
;
; RUN: opt < %s -passes='cgscc(inline,function(verify<domtree>))' -debug-pass-manager -S 2>&1 | FileCheck %s
; First we check that the passes run in the way we expect. Otherwise this test
; may stop testing anything.
;
; CHECK-LABEL: Starting llvm::Module pass manager run.
; CHECK: Running pass: InlinerPass on (test1_f, test1_g, test1_h)
; CHECK: Running analysis: DominatorTreeAnalysis on test1_f
; CHECK: Running analysis: DominatorTreeAnalysis on test1_g
; CHECK: Invalidating all non-preserved analyses for: (test1_f)
; CHECK: Invalidating all non-preserved analyses for: test1_f
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_f
; CHECK: Invalidating analysis: LoopAnalysis on test1_f
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_f
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_f
; CHECK: Invalidating all non-preserved analyses for: (test1_g, test1_h)
; CHECK: Invalidating all non-preserved analyses for: test1_g
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_g
; CHECK: Invalidating analysis: LoopAnalysis on test1_g
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_g
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_g
; CHECK: Invalidating all non-preserved analyses for: test1_h
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_h
; CHECK: Invalidating analysis: LoopAnalysis on test1_h
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_h
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_h
; CHECK-NOT: Invalidating analysis:
; CHECK: Starting llvm::Function pass manager run.
; CHECK-NEXT: Running pass: DominatorTreeVerifierPass on test1_g
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_g
; CHECK-NEXT: Finished llvm::Function pass manager run.
; CHECK-NOT: Invalidating analysis:
; CHECK: Starting llvm::Function pass manager run.
; CHECK-NEXT: Running pass: DominatorTreeVerifierPass on test1_h
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_h
; CHECK-NEXT: Finished llvm::Function pass manager run.
; CHECK-NOT: Invalidating analysis:
; CHECK: Running pass: DominatorTreeVerifierPass on test1_f
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_f
; An external function used to control branches.
declare i1 @flag()
; CHECK-LABEL: declare i1 @flag()
; The utility function with interesting control flow that gets inlined below to
; perturb the dominator tree.
define internal void @callee() {
entry:
%ptr = alloca i8
%flag = call i1 @flag()
br i1 %flag, label %then, label %else
then:
store volatile i8 42, i8* %ptr
br label %return
else:
store volatile i8 -42, i8* %ptr
br label %return
return:
ret void
}
; The 'test1_' prefixed functions work to carefully test that incrementally
; reducing an SCC in the inliner cannot accidentially leave stale function
; analysis results due to failing to invalidate them for all the functions.
; The inliner visits this last function. It can't actually break any cycles
; here, but because we visit this function we compute fresh analyses for it.
; These analyses are then invalidated when we inline callee disrupting the
; CFG, and it is important that they be freed.
define void @test1_h() {
; CHECK-LABEL: define void @test1_h()
entry:
call void @test1_g()
; CHECK: call void @test1_g()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; We visit this function second and here we inline the edge to 'test1_f'
; separating it into its own SCC. The current SCC is now just 'test1_g' and
; 'test1_h'.
define void @test1_g() {
; CHECK-LABEL: define void @test1_g()
entry:
; This edge gets inlined away.
call void @test1_f()
; CHECK-NOT: call void @test1_f()
; CHECK: call void @test1_g()
; We force this edge to survive inlining.
call void @test1_h() noinline
; CHECK: call void @test1_h()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; We visit this function first in the inliner, and while we inline callee
; perturbing the CFG, we don't inline anything else and the SCC structure
; remains in tact.
define void @test1_f() {
; CHECK-LABEL: define void @test1_f()
entry:
; We force this edge to survive inlining.
call void @test1_g() noinline
; CHECK: call void @test1_g()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; The 'test2_' prefixed code works to carefully trigger forming an SCC with
; a dominator tree for one of the functions but not the other and without even
; a function analysis manager proxy for the SCC that things get merged into.
; Without proper handling when updating the call graph this will find a stale
; dominator tree.
@test2_global = external global i32, align 4
define void @test2_hoge(i1 (i32*)* %arg) {
; CHECK-LABEL: define void @test2_hoge(
bb:
%tmp2 = call zeroext i1 %arg(i32* @test2_global)
; CHECK: call zeroext i1 %arg(
br label %bb3
bb3:
%tmp5 = call zeroext i1 %arg(i32* @test2_global)
; CHECK: call zeroext i1 %arg(
br i1 %tmp5, label %bb3, label %bb6
bb6:
ret void
}
define zeroext i1 @test2_widget(i32* %arg) {
; CHECK-LABEL: define zeroext i1 @test2_widget(
bb:
%tmp1 = alloca i8, align 1
%tmp2 = alloca i32, align 4
call void @test2_quux()
; CHECK-NOT: call
;
; CHECK: call zeroext i1 @test2_widget(i32* @test2_global)
; CHECK-NEXT: br label %[[NEW_BB:.*]]
;
; CHECK: [[NEW_BB]]:
; CHECK-NEXT: call zeroext i1 @test2_widget(i32* @test2_global)
;
; CHECK: {{.*}}:
call void @test2_hoge.1(i32* %arg)
; CHECK-NEXT: call void @test2_hoge.1(
%tmp4 = call zeroext i1 @test2_barney(i32* %tmp2)
%tmp5 = zext i1 %tmp4 to i32
store i32 %tmp5, i32* %tmp2, align 4
%tmp6 = call zeroext i1 @test2_barney(i32* null)
call void @test2_ham(i8* %tmp1)
; CHECK: call void @test2_ham(
call void @test2_quux()
; CHECK-NOT: call
;
; CHECK: call zeroext i1 @test2_widget(i32* @test2_global)
; CHECK-NEXT: br label %[[NEW_BB:.*]]
;
; CHECK: [[NEW_BB]]:
; CHECK-NEXT: call zeroext i1 @test2_widget(i32* @test2_global)
;
; CHECK: {{.*}}:
ret i1 true
; CHECK-NEXT: ret i1 true
}
define internal void @test2_quux() {
; CHECK-NOT: @test2_quux
bb:
call void @test2_hoge(i1 (i32*)* @test2_widget)
ret void
}
declare void @test2_hoge.1(i32*)
declare zeroext i1 @test2_barney(i32*)
declare void @test2_ham(i8*)
|