- //===- ASTUnresolvedSet.h - Unresolved sets of declarations -----*- C++ -*-===// 
- // 
- // 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 
- // 
- //===----------------------------------------------------------------------===// 
- // 
- //  This file provides an UnresolvedSet-like class, whose contents are 
- //  allocated using the allocator associated with an ASTContext. 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_CLANG_AST_ASTUNRESOLVEDSET_H 
- #define LLVM_CLANG_AST_ASTUNRESOLVEDSET_H 
-   
- #include "clang/AST/ASTVector.h" 
- #include "clang/AST/DeclAccessPair.h" 
- #include "clang/AST/UnresolvedSet.h" 
- #include "clang/Basic/Specifiers.h" 
- #include <cassert> 
- #include <cstdint> 
-   
- namespace clang { 
-   
- class NamedDecl; 
-   
- /// An UnresolvedSet-like class which uses the ASTContext's allocator. 
- class ASTUnresolvedSet { 
-   friend class LazyASTUnresolvedSet; 
-   
-   struct DeclsTy : ASTVector<DeclAccessPair> { 
-     DeclsTy() = default; 
-     DeclsTy(ASTContext &C, unsigned N) : ASTVector<DeclAccessPair>(C, N) {} 
-   
-     bool isLazy() const { return getTag(); } 
-     void setLazy(bool Lazy) { setTag(Lazy); } 
-   }; 
-   
-   DeclsTy Decls; 
-   
- public: 
-   ASTUnresolvedSet() = default; 
-   ASTUnresolvedSet(ASTContext &C, unsigned N) : Decls(C, N) {} 
-   
-   using iterator = UnresolvedSetIterator; 
-   using const_iterator = UnresolvedSetIterator; 
-   
-   iterator begin() { return iterator(Decls.begin()); } 
-   iterator end() { return iterator(Decls.end()); } 
-   
-   const_iterator begin() const { return const_iterator(Decls.begin()); } 
-   const_iterator end() const { return const_iterator(Decls.end()); } 
-   
-   void addDecl(ASTContext &C, NamedDecl *D, AccessSpecifier AS) { 
-     Decls.push_back(DeclAccessPair::make(D, AS), C); 
-   } 
-   
-   /// Replaces the given declaration with the new one, once. 
-   /// 
-   /// \return true if the set changed 
-   bool replace(const NamedDecl *Old, NamedDecl *New, AccessSpecifier AS) { 
-     for (DeclsTy::iterator I = Decls.begin(), E = Decls.end(); I != E; ++I) { 
-       if (I->getDecl() == Old) { 
-         I->set(New, AS); 
-         return true; 
-       } 
-     } 
-     return false; 
-   } 
-   
-   void erase(unsigned I) { 
-     if (I == Decls.size() - 1) 
-       Decls.pop_back(); 
-     else 
-       Decls[I] = Decls.pop_back_val(); 
-   } 
-   
-   void clear() { Decls.clear(); } 
-   
-   bool empty() const { return Decls.empty(); } 
-   unsigned size() const { return Decls.size(); } 
-   
-   void reserve(ASTContext &C, unsigned N) { 
-     Decls.reserve(C, N); 
-   } 
-   
-   void append(ASTContext &C, iterator I, iterator E) { 
-     Decls.append(C, I.I, E.I); 
-   } 
-   
-   DeclAccessPair &operator[](unsigned I) { return Decls[I]; } 
-   const DeclAccessPair &operator[](unsigned I) const { return Decls[I]; } 
- }; 
-   
- /// An UnresolvedSet-like class that might not have been loaded from the 
- /// external AST source yet. 
- class LazyASTUnresolvedSet { 
-   mutable ASTUnresolvedSet Impl; 
-   
-   void getFromExternalSource(ASTContext &C) const; 
-   
- public: 
-   ASTUnresolvedSet &get(ASTContext &C) const { 
-     if (Impl.Decls.isLazy()) 
-       getFromExternalSource(C); 
-     return Impl; 
-   } 
-   
-   void reserve(ASTContext &C, unsigned N) { Impl.reserve(C, N); } 
-   
-   void addLazyDecl(ASTContext &C, uintptr_t ID, AccessSpecifier AS) { 
-     assert(Impl.empty() || Impl.Decls.isLazy()); 
-     Impl.Decls.setLazy(true); 
-     Impl.addDecl(C, reinterpret_cast<NamedDecl *>(ID << 2), AS); 
-   } 
- }; 
-   
- } // namespace clang 
-   
- #endif // LLVM_CLANG_AST_ASTUNRESOLVEDSET_H 
-