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
|
// RUN: %clang_cc1 -no-opaque-pointers %s -fno-rtti -triple=i386-pc-win32 -emit-llvm -o %t.ll -fdump-vtable-layouts >%t
// RUN: FileCheck %s < %t
// RUN: FileCheck --check-prefix=BITCODE %s < %t.ll
namespace test1 {
struct A {
virtual void g();
// Add an extra virtual method so it's easier to check for the absence of thunks.
virtual void h();
};
struct B {
virtual void g(); // Collides with A::g if both are bases of some class.
};
// Overrides methods of two bases at the same time, thus needing thunks.
struct X : A, B {
// CHECK-LABEL: VFTable for 'test1::A' in 'test1::X' (2 entries).
// CHECK-NEXT: 0 | void test1::X::g()
// CHECK-NEXT: 1 | void test1::A::h()
// CHECK-LABEL: VFTable for 'test1::B' in 'test1::X' (1 entry).
// CHECK-NEXT: 0 | void test1::X::g()
// CHECK-NEXT: [this adjustment: -4 non-virtual]
// CHECK-LABEL: Thunks for 'void test1::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -4 non-virtual]
// CHECK-LABEL: VFTable indices for 'test1::X' (1 entry).
// CHECK-NEXT: 0 | void test1::X::g()
// BITCODE-DAG: @"??_7X@test1@@6BA@1@@"
// BITCODE-DAG: @"??_7X@test1@@6BB@1@@"
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test2 {
struct A {
virtual void f();
};
struct B {
virtual void g();
virtual void h();
};
struct C {
virtual void g();
};
struct X : A, B, C {
// CHECK-LABEL: VFTable for 'test2::A' in 'test2::X' (1 entry).
// CHECK-NEXT: 0 | void test2::A::f()
// CHECK-LABEL: VFTable for 'test2::B' in 'test2::X' (2 entries).
// CHECK-NEXT: 0 | void test2::X::g()
// CHECK-NEXT: 1 | void test2::B::h()
// CHECK-LABEL: VFTable for 'test2::C' in 'test2::X' (1 entry).
// CHECK-NEXT: 0 | void test2::X::g()
// CHECK-NEXT: [this adjustment: -4 non-virtual]
// CHECK-LABEL: Thunks for 'void test2::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -4 non-virtual]
// CHECK-LABEL: VFTable indices for 'test2::X' (1 entry).
// CHECK-NEXT: via vfptr at offset 4
// CHECK-NEXT: 0 | void test2::X::g()
// BITCODE-DAG: @"??_7X@test2@@6BA@1@@"
// BITCODE-DAG: @"??_7X@test2@@6BB@1@@"
// BITCODE-DAG: @"??_7X@test2@@6BC@1@@"
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test3 {
struct A {
virtual void f();
};
struct B {
virtual void g();
virtual void h();
};
struct C: A, B {
// Overrides only the left child's method (A::f), needs no thunks.
virtual void f();
};
struct D: A, B {
// Overrides only the right child's method (B::g),
// needs this adjustment but not thunks.
virtual void g();
};
// Overrides methods of two bases at the same time, thus needing thunks.
struct X: C, D {
// CHECK-LABEL: VFTable for 'test3::A' in 'test3::C' in 'test3::X' (1 entry).
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-LABEL: VFTable for 'test3::B' in 'test3::C' in 'test3::X' (2 entries).
// CHECK-NEXT: 0 | void test3::X::g()
// CHECK-NEXT: 1 | void test3::B::h()
// CHECK-LABEL: VFTable for 'test3::A' in 'test3::D' in 'test3::X' (1 entry).
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-NEXT: [this adjustment: -8 non-virtual]
// CHECK-LABEL: Thunks for 'void test3::X::f()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -8 non-virtual]
// CHECK-LABEL: VFTable for 'test3::B' in 'test3::D' in 'test3::X' (2 entries).
// CHECK-NEXT: 0 | void test3::X::g()
// CHECK-NEXT: [this adjustment: -8 non-virtual]
// CHECK-NEXT: 1 | void test3::B::h()
// CHECK-LABEL: Thunks for 'void test3::X::g()' (1 entry).
// CHECK-NEXT: 0 | [this adjustment: -8 non-virtual]
// CHECK-LABEL: VFTable indices for 'test3::X' (2 entries).
// CHECK-NEXT: via vfptr at offset 0
// CHECK-NEXT: 0 | void test3::X::f()
// CHECK-NEXT: via vfptr at offset 4
// CHECK-NEXT: 0 | void test3::X::g()
virtual void f();
virtual void g();
} x;
void build_vftable(X *obj) { obj->g(); }
}
namespace test4 {
struct A {
virtual void foo();
};
struct B {
virtual int filler();
virtual int operator-();
virtual int bar();
};
struct C : public A, public B {
virtual int filler();
virtual int operator-();
virtual int bar();
};
// BITCODE-LABEL: define {{.*}}"?ffun@test4@@YAXAAUC@1@@Z
void ffun(C &c) {
// BITCODE: [[THIS1:%.+]] = bitcast %"struct.test4::C"* {{.*}} to i8*
// BITCODE: [[THIS2:%.+]] = getelementptr inbounds i8, i8* [[THIS1]], i32 4
// BITCODE: call x86_thiscallcc {{.*}}(i8* noundef [[THIS2]])
c.bar();
}
// BITCODE-LABEL: define {{.*}}"?fop@test4@@YAXAAUC@1@@Z
void fop(C &c) {
// BITCODE: [[THIS1:%.+]] = bitcast %"struct.test4::C"* {{.*}} to i8*
// BITCODE: [[THIS2:%.+]] = getelementptr inbounds i8, i8* [[THIS1]], i32 4
// BITCODE: call x86_thiscallcc {{.*}}(i8* noundef [[THIS2]])
-c;
}
}
namespace pr30293 {
struct NonTrivial {
~NonTrivial();
int x;
};
struct A { virtual void f(); };
struct B { virtual void __cdecl g(NonTrivial); };
struct C final : A, B {
void f() override;
void __cdecl g(NonTrivial) override;
};
C *whatsthis;
void C::f() { g(NonTrivial()); }
void C::g(NonTrivial o) {
whatsthis = this;
}
// BITCODE-LABEL: define dso_local void @"?g@C@pr30293@@UAAXUNonTrivial@2@@Z"(<{ i8*, %"struct.pr30293::NonTrivial" }>* inalloca(<{ i8*, %"struct.pr30293::NonTrivial" }>) %0)
// BITCODE: %[[thisaddr:[^ ]*]] = getelementptr inbounds <{ i8*, %"struct.pr30293::NonTrivial" }>, <{ i8*, %"struct.pr30293::NonTrivial" }>* {{.*}}, i32 0, i32 0
// BITCODE: %[[thisaddr1:[^ ]*]] = bitcast i8** %[[thisaddr]] to %"struct.pr30293::C"**
// BITCODE: %[[this1:[^ ]*]] = load %"struct.pr30293::C"*, %"struct.pr30293::C"** %[[thisaddr1]], align 4
// BITCODE: %[[this2:[^ ]*]] = bitcast %"struct.pr30293::C"* %[[this1]] to i8*
// BITCODE: %[[this3:[^ ]*]] = getelementptr inbounds i8, i8* %[[this2]], i32 -4
// BITCODE: %[[this4:[^ ]*]] = bitcast i8* %[[this3]] to %"struct.pr30293::C"*
// BITCODE: store %"struct.pr30293::C"* %[[this4]], %"struct.pr30293::C"** @"?whatsthis@pr30293@@3PAUC@1@A", align 4
}
|
