- //===- StmtIterator.h - Iterators for Statements ----------------*- 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 defines the StmtIterator and ConstStmtIterator classes. 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_CLANG_AST_STMTITERATOR_H 
- #define LLVM_CLANG_AST_STMTITERATOR_H 
-   
- #include <cassert> 
- #include <cstddef> 
- #include <cstdint> 
- #include <iterator> 
-   
- namespace clang { 
-   
- class Decl; 
- class Stmt; 
- class VariableArrayType; 
-   
- class StmtIteratorBase { 
- protected: 
-   enum { 
-     StmtMode = 0x0, 
-     SizeOfTypeVAMode = 0x1, 
-     DeclGroupMode = 0x2, 
-     Flags = 0x3 
-   }; 
-   
-   union { 
-     Stmt **stmt; 
-     Decl **DGI; 
-   }; 
-   uintptr_t RawVAPtr = 0; 
-   Decl **DGE; 
-   
-   StmtIteratorBase(Stmt **s) : stmt(s) {} 
-   StmtIteratorBase(const VariableArrayType *t); 
-   StmtIteratorBase(Decl **dgi, Decl **dge); 
-   StmtIteratorBase() : stmt(nullptr) {} 
-   
-   bool inDeclGroup() const { 
-     return (RawVAPtr & Flags) == DeclGroupMode; 
-   } 
-   
-   bool inSizeOfTypeVA() const { 
-     return (RawVAPtr & Flags) == SizeOfTypeVAMode; 
-   } 
-   
-   bool inStmt() const { 
-     return (RawVAPtr & Flags) == StmtMode; 
-   } 
-   
-   const VariableArrayType *getVAPtr() const { 
-     return reinterpret_cast<const VariableArrayType*>(RawVAPtr & ~Flags); 
-   } 
-   
-   void setVAPtr(const VariableArrayType *P) { 
-     assert(inDeclGroup() || inSizeOfTypeVA()); 
-     RawVAPtr = reinterpret_cast<uintptr_t>(P) | (RawVAPtr & Flags); 
-   } 
-   
-   void NextDecl(bool ImmediateAdvance = true); 
-   bool HandleDecl(Decl* D); 
-   void NextVA(); 
-   
-   Stmt*& GetDeclExpr() const; 
- }; 
-   
- template <typename DERIVED, typename REFERENCE> 
- class StmtIteratorImpl : public StmtIteratorBase { 
- protected: 
-   StmtIteratorImpl(const StmtIteratorBase& RHS) : StmtIteratorBase(RHS) {} 
-   
- public: 
-   using iterator_category = std::forward_iterator_tag; 
-   using value_type = REFERENCE; 
-   using difference_type = std::ptrdiff_t; 
-   using pointer = REFERENCE; 
-   using reference = REFERENCE; 
-   
-   StmtIteratorImpl() = default; 
-   StmtIteratorImpl(Stmt **s) : StmtIteratorBase(s) {} 
-   StmtIteratorImpl(Decl **dgi, Decl **dge) : StmtIteratorBase(dgi, dge) {} 
-   StmtIteratorImpl(const VariableArrayType *t) : StmtIteratorBase(t) {} 
-   
-   DERIVED& operator++() { 
-     if (inStmt()) 
-       ++stmt; 
-     else if (getVAPtr()) 
-       NextVA(); 
-     else 
-       NextDecl(); 
-   
-     return static_cast<DERIVED&>(*this); 
-   } 
-   
-   DERIVED operator++(int) { 
-     DERIVED tmp = static_cast<DERIVED&>(*this); 
-     operator++(); 
-     return tmp; 
-   } 
-   
-   friend bool operator==(const DERIVED &LHS, const DERIVED &RHS) { 
-     return LHS.stmt == RHS.stmt && LHS.DGI == RHS.DGI && 
-            LHS.RawVAPtr == RHS.RawVAPtr; 
-   } 
-   
-   friend bool operator!=(const DERIVED &LHS, const DERIVED &RHS) { 
-     return !(LHS == RHS); 
-   } 
-   
-   REFERENCE operator*() const { 
-     return inStmt() ? *stmt : GetDeclExpr(); 
-   } 
-   
-   REFERENCE operator->() const { return operator*(); } 
- }; 
-   
- struct ConstStmtIterator; 
-   
- struct StmtIterator : public StmtIteratorImpl<StmtIterator, Stmt*&> { 
-   explicit StmtIterator() = default; 
-   StmtIterator(Stmt** S) : StmtIteratorImpl<StmtIterator, Stmt*&>(S) {} 
-   StmtIterator(Decl** dgi, Decl** dge) 
-       : StmtIteratorImpl<StmtIterator, Stmt*&>(dgi, dge) {} 
-   StmtIterator(const VariableArrayType *t) 
-       : StmtIteratorImpl<StmtIterator, Stmt*&>(t) {} 
-   
- private: 
-   StmtIterator(const StmtIteratorBase &RHS) 
-       : StmtIteratorImpl<StmtIterator, Stmt *&>(RHS) {} 
-   
-   inline friend StmtIterator 
-   cast_away_const(const ConstStmtIterator &RHS); 
- }; 
-   
- struct ConstStmtIterator : public StmtIteratorImpl<ConstStmtIterator, 
-                                                    const Stmt*> { 
-   explicit ConstStmtIterator() = default; 
-   ConstStmtIterator(const StmtIterator& RHS) 
-       : StmtIteratorImpl<ConstStmtIterator, const Stmt*>(RHS) {} 
-   
-   ConstStmtIterator(Stmt * const *S) 
-       : StmtIteratorImpl<ConstStmtIterator, const Stmt *>( 
-             const_cast<Stmt **>(S)) {} 
- }; 
-   
- inline StmtIterator cast_away_const(const ConstStmtIterator &RHS) { 
-   return RHS; 
- } 
-   
- } // namespace clang 
-   
- #endif // LLVM_CLANG_AST_STMTITERATOR_H 
-