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
|
//===--- TypeTraits.cpp - clang-tidy---------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "TypeTraits.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclCXX.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
namespace clang {
namespace tidy {
namespace utils {
namespace type_traits {
namespace {
bool classHasTrivialCopyAndDestroy(QualType Type) {
auto *Record = Type->getAsCXXRecordDecl();
return Record && Record->hasDefinition() &&
!Record->hasNonTrivialCopyConstructor() &&
!Record->hasNonTrivialDestructor();
}
bool hasDeletedCopyConstructor(QualType Type) {
auto *Record = Type->getAsCXXRecordDecl();
if (!Record || !Record->hasDefinition())
return false;
for (const auto *Constructor : Record->ctors()) {
if (Constructor->isCopyConstructor() && Constructor->isDeleted())
return true;
}
return false;
}
} // namespace
llvm::Optional<bool> isExpensiveToCopy(QualType Type,
const ASTContext &Context) {
if (Type->isDependentType() || Type->isIncompleteType())
return llvm::None;
return !Type.isTriviallyCopyableType(Context) &&
!classHasTrivialCopyAndDestroy(Type) &&
!hasDeletedCopyConstructor(Type) &&
!Type->isObjCLifetimeType();
}
bool recordIsTriviallyDefaultConstructible(const RecordDecl &RecordDecl,
const ASTContext &Context) {
const auto *ClassDecl = dyn_cast<CXXRecordDecl>(&RecordDecl);
// Non-C++ records are always trivially constructible.
if (!ClassDecl)
return true;
// It is impossible to determine whether an ill-formed decl is trivially
// constructible.
if (RecordDecl.isInvalidDecl())
return false;
// A class with a user-provided default constructor is not trivially
// constructible.
if (ClassDecl->hasUserProvidedDefaultConstructor())
return false;
// A polymorphic class is not trivially constructible
if (ClassDecl->isPolymorphic())
return false;
// A class is trivially constructible if it has a trivial default constructor.
if (ClassDecl->hasTrivialDefaultConstructor())
return true;
// If all its fields are trivially constructible and have no default
// initializers.
for (const FieldDecl *Field : ClassDecl->fields()) {
if (Field->hasInClassInitializer())
return false;
if (!isTriviallyDefaultConstructible(Field->getType(), Context))
return false;
}
// If all its direct bases are trivially constructible.
for (const CXXBaseSpecifier &Base : ClassDecl->bases()) {
if (!isTriviallyDefaultConstructible(Base.getType(), Context))
return false;
if (Base.isVirtual())
return false;
}
return true;
}
// Based on QualType::isTrivial.
bool isTriviallyDefaultConstructible(QualType Type, const ASTContext &Context) {
if (Type.isNull())
return false;
if (Type->isArrayType())
return isTriviallyDefaultConstructible(Context.getBaseElementType(Type),
Context);
// Return false for incomplete types after skipping any incomplete array
// types which are expressly allowed by the standard and thus our API.
if (Type->isIncompleteType())
return false;
if (Context.getLangOpts().ObjCAutoRefCount) {
switch (Type.getObjCLifetime()) {
case Qualifiers::OCL_ExplicitNone:
return true;
case Qualifiers::OCL_Strong:
case Qualifiers::OCL_Weak:
case Qualifiers::OCL_Autoreleasing:
return false;
case Qualifiers::OCL_None:
if (Type->isObjCLifetimeType())
return false;
break;
}
}
QualType CanonicalType = Type.getCanonicalType();
if (CanonicalType->isDependentType())
return false;
// As an extension, Clang treats vector types as Scalar types.
if (CanonicalType->isScalarType() || CanonicalType->isVectorType())
return true;
if (const auto *RT = CanonicalType->getAs<RecordType>()) {
return recordIsTriviallyDefaultConstructible(*RT->getDecl(), Context);
}
// No other types can match.
return false;
}
// Based on QualType::isDestructedType.
bool isTriviallyDestructible(QualType Type) {
if (Type.isNull())
return false;
if (Type->isIncompleteType())
return false;
if (Type.getCanonicalType()->isDependentType())
return false;
return Type.isDestructedType() == QualType::DK_none;
}
bool hasNonTrivialMoveConstructor(QualType Type) {
auto *Record = Type->getAsCXXRecordDecl();
return Record && Record->hasDefinition() &&
Record->hasNonTrivialMoveConstructor();
}
bool hasNonTrivialMoveAssignment(QualType Type) {
auto *Record = Type->getAsCXXRecordDecl();
return Record && Record->hasDefinition() &&
Record->hasNonTrivialMoveAssignment();
}
} // namespace type_traits
} // namespace utils
} // namespace tidy
} // namespace clang
|
