clang/lib/AST/DeclFriend.cpp

   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/Decl.h"
  16 #include "clang/AST/DeclBase.h"
  17 #include "clang/AST/DeclCXX.h"
  18 #include "clang/AST/ASTContext.h"
  19 #include "clang/AST/DeclTemplate.h"
  20 #include "clang/Basic/LLVM.h"
  21 #include "llvm/Support/Casting.h"
  22 #include <cassert>
  23 #include <cstddef>
  24
  25 using namespace clang;
  26
  27 void FriendDecl::anchor() {}
  28
  29 FriendDecl *FriendDecl::getNextFriendSlowCase() {
  30   return cast_or_null<FriendDecl>(
  31                            NextFriend.get(getASTContext().getExternalSource()));
  32 }
  33
  34 FriendDecl *FriendDecl::Create(ASTContext &C, DeclContext *DC,
  35                                SourceLocation L,
  36                                FriendUnion Friend,
  37                                SourceLocation FriendL,
  38                           ArrayRef<TemplateParameterList *> FriendTypeTPLists) {
  39 #ifndef NDEBUG
  40   if (Friend.is<NamedDecl *>()) {
  41     const auto *D = Friend.get<NamedDecl*>();
  42     assert(isa<FunctionDecl>(D) ||
  43            isa<CXXRecordDecl>(D) ||
  44            isa<FunctionTemplateDecl>(D) ||
  45            isa<ClassTemplateDecl>(D));
  46
  47     // As a temporary hack, we permit template instantiation to point
  48     // to the original declaration when instantiating members.
  49     assert(D->getFriendObjectKind() ||
  50            (cast<CXXRecordDecl>(DC)->getTemplateSpecializationKind()));
  51     // These template parameters are for friend types only.
  52     assert(FriendTypeTPLists.empty());
  53   }
  54 #endif
  55
  56   std::size_t Extra =
  57       FriendDecl::additionalSizeToAlloc<TemplateParameterList *>(
  58           FriendTypeTPLists.size());
  59   auto *FD = new (C, DC, Extra) FriendDecl(DC, L, Friend, FriendL,
  60                                            FriendTypeTPLists);
  61   cast<CXXRecordDecl>(DC)->pushFriendDecl(FD);
  62   return FD;
  63 }
  64
  65 FriendDecl *FriendDecl::CreateDeserialized(ASTContext &C, unsigned ID,
  66                                            unsigned FriendTypeNumTPLists) {
  67   std::size_t Extra =
  68       additionalSizeToAlloc<TemplateParameterList *>(FriendTypeNumTPLists);
  69   return new (C, ID, Extra) FriendDecl(EmptyShell(), FriendTypeNumTPLists);
  70 }
  71
  72 FriendDecl *CXXRecordDecl::getFirstFriend() const {
  73   ExternalASTSource *Source = getParentASTContext().getExternalSource();
  74   Decl *First = data().FirstFriend.get(Source);
  75   return First ? cast<FriendDecl>(First) : nullptr;
  76 }