1//===- ASTCommon.h - Common stuff for ASTReader/ASTWriter -*- C++ -*-=========//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file defines common functions that both ASTReader and ASTWriter use.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_LIB_SERIALIZATION_ASTCOMMON_H
14#define LLVM_CLANG_LIB_SERIALIZATION_ASTCOMMON_H
15
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/DeclFriend.h"
18#include "clang/Serialization/ASTBitCodes.h"
19
20namespace clang {
21
22namespace serialization {
23
24enum DeclUpdateKind {
25  UPD_CXX_ADDED_IMPLICIT_MEMBER,
26  UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION,
27  UPD_CXX_ADDED_ANONYMOUS_NAMESPACE,
28  UPD_CXX_ADDED_FUNCTION_DEFINITION,
29  UPD_CXX_ADDED_VAR_DEFINITION,
30  UPD_CXX_POINT_OF_INSTANTIATION,
31  UPD_CXX_INSTANTIATED_CLASS_DEFINITION,
32  UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT,
33  UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER,
34  UPD_CXX_RESOLVED_DTOR_DELETE,
35  UPD_CXX_RESOLVED_EXCEPTION_SPEC,
36  UPD_CXX_DEDUCED_RETURN_TYPE,
37  UPD_DECL_MARKED_USED,
38  UPD_MANGLING_NUMBER,
39  UPD_STATIC_LOCAL_NUMBER,
40  UPD_DECL_MARKED_OPENMP_THREADPRIVATE,
41  UPD_DECL_MARKED_OPENMP_ALLOCATE,
42  UPD_DECL_MARKED_OPENMP_DECLARETARGET,
43  UPD_DECL_EXPORTED,
44  UPD_ADDED_ATTR_TO_RECORD
45};
46
47TypeIdx TypeIdxFromBuiltin(const BuiltinType *BT);
48
49template <typename IdxForTypeTy>
50TypeID MakeTypeID(ASTContext &Context, QualType T, IdxForTypeTy IdxForType) {
51  if (T.isNull())
52    return PREDEF_TYPE_NULL_ID;
53
54  unsigned FastQuals = T.getLocalFastQualifiers();
55  T.removeLocalFastQualifiers();
56
57  if (T.hasLocalNonFastQualifiers())
58    return IdxForType(T).asTypeID(FastQuals);
59
60  assert(!T.hasLocalQualifiers());
61
62  if (const BuiltinType *BT = dyn_cast<BuiltinType>(T.getTypePtr()))
63    return TypeIdxFromBuiltin(BT).asTypeID(FastQuals);
64
65  if (T == Context.AutoDeductTy)
66    return TypeIdx(PREDEF_TYPE_AUTO_DEDUCT).asTypeID(FastQuals);
67  if (T == Context.AutoRRefDeductTy)
68    return TypeIdx(PREDEF_TYPE_AUTO_RREF_DEDUCT).asTypeID(FastQuals);
69
70  return IdxForType(T).asTypeID(FastQuals);
71}
72
73unsigned ComputeHash(Selector Sel);
74
75/// Retrieve the "definitive" declaration that provides all of the
76/// visible entries for the given declaration context, if there is one.
77///
78/// The "definitive" declaration is the only place where we need to look to
79/// find information about the declarations within the given declaration
80/// context. For example, C++ and Objective-C classes, C structs/unions, and
81/// Objective-C protocols, categories, and extensions are all defined in a
82/// single place in the source code, so they have definitive declarations
83/// associated with them. C++ namespaces, on the other hand, can have
84/// multiple definitions.
85const DeclContext *getDefinitiveDeclContext(const DeclContext *DC);
86
87/// Determine whether the given declaration kind is redeclarable.
88bool isRedeclarableDeclKind(unsigned Kind);
89
90/// Determine whether the given declaration needs an anonymous
91/// declaration number.
92bool needsAnonymousDeclarationNumber(const NamedDecl *D);
93
94/// Visit each declaration within \c DC that needs an anonymous
95/// declaration number and call \p Visit with the declaration and its number.
96template<typename Fn> void numberAnonymousDeclsWithin(const DeclContext *DC,
97                                                      Fn Visit) {
98  unsigned Index = 0;
99  for (Decl *LexicalD : DC->decls()) {
100    // For a friend decl, we care about the declaration within it, if any.
101    if (auto *FD = dyn_cast<FriendDecl>(LexicalD))
102      LexicalD = FD->getFriendDecl();
103
104    auto *ND = dyn_cast_or_null<NamedDecl>(LexicalD);
105    if (!ND || !needsAnonymousDeclarationNumber(ND))
106      continue;
107
108    Visit(ND, Index++);
109  }
110}
111
112/// Determine whether the given declaration will be included in the per-module
113/// initializer if it needs to be eagerly handed to the AST consumer. If so, we
114/// should not hand it to the consumer when deserializing it, nor include it in
115/// the list of eagerly deserialized declarations.
116inline bool isPartOfPerModuleInitializer(const Decl *D) {
117  if (isa<ImportDecl>(D))
118    return true;
119  // Template instantiations are notionally in an "instantiation unit" rather
120  // than in any particular translation unit, so they need not be part of any
121  // particular (sub)module's per-module initializer.
122  if (auto *VD = dyn_cast<VarDecl>(D))
123    return !isTemplateInstantiation(VD->getTemplateSpecializationKind());
124  return false;
125}
126
127} // namespace serialization
128
129} // namespace clang
130
131#endif
132