xref: /llvm-project/clang/lib/AST/DeclFriend.cpp (revision 63d9ef5e37539b8920eb6c93524e4be2c33a510c)
1 //===- DeclFriend.cpp - C++ Friend Declaration AST Node Implementation ----===//
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 implements the AST classes related to C++ friend
10 // declarations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/DeclFriend.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclBase.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/Basic/LLVM.h"
21 #include <cassert>
22 #include <cstddef>
23 
24 using namespace clang;
25 
26 void FriendDecl::anchor() {}
27 
28 FriendDecl *FriendDecl::getNextFriendSlowCase() {
29   return cast_or_null<FriendDecl>(
30                            NextFriend.get(getASTContext().getExternalSource()));
31 }
32 
33 FriendDecl *
34 FriendDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L,
35                    FriendUnion Friend, SourceLocation FriendL,
36                    SourceLocation EllipsisLoc,
37                    ArrayRef<TemplateParameterList *> FriendTypeTPLists) {
38 #ifndef NDEBUG
39   if (const auto *D = dyn_cast<NamedDecl *>(Friend)) {
40     assert(isa<FunctionDecl>(D) ||
41            isa<CXXRecordDecl>(D) ||
42            isa<FunctionTemplateDecl>(D) ||
43            isa<ClassTemplateDecl>(D));
44 
45     // As a temporary hack, we permit template instantiation to point
46     // to the original declaration when instantiating members.
47     assert(D->getFriendObjectKind() ||
48            (cast<CXXRecordDecl>(DC)->getTemplateSpecializationKind()));
49     // These template parameters are for friend types only.
50     assert(FriendTypeTPLists.empty());
51   }
52 #endif
53 
54   std::size_t Extra =
55       FriendDecl::additionalSizeToAlloc<TemplateParameterList *>(
56           FriendTypeTPLists.size());
57   auto *FD = new (C, DC, Extra)
58       FriendDecl(DC, L, Friend, FriendL, EllipsisLoc, FriendTypeTPLists);
59   cast<CXXRecordDecl>(DC)->pushFriendDecl(FD);
60   return FD;
61 }
62 
63 FriendDecl *FriendDecl::CreateDeserialized(ASTContext &C, GlobalDeclID ID,
64                                            unsigned FriendTypeNumTPLists) {
65   std::size_t Extra =
66       additionalSizeToAlloc<TemplateParameterList *>(FriendTypeNumTPLists);
67   return new (C, ID, Extra) FriendDecl(EmptyShell(), FriendTypeNumTPLists);
68 }
69 
70 FriendDecl *CXXRecordDecl::getFirstFriend() const {
71   ExternalASTSource *Source = getParentASTContext().getExternalSource();
72   Decl *First = data().FirstFriend.get(Source);
73   return First ? cast<FriendDecl>(First) : nullptr;
74 }
75