- //===- ASTWriter.h - AST File Writer ----------------------------*- 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 ASTWriter class, which writes an AST file 
- //  containing a serialized representation of a translation unit. 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_CLANG_SERIALIZATION_ASTWRITER_H 
- #define LLVM_CLANG_SERIALIZATION_ASTWRITER_H 
-   
- #include "clang/AST/ASTMutationListener.h" 
- #include "clang/AST/Decl.h" 
- #include "clang/AST/Type.h" 
- #include "clang/Basic/LLVM.h" 
- #include "clang/Basic/Module.h" 
- #include "clang/Basic/SourceLocation.h" 
- #include "clang/Sema/Sema.h" 
- #include "clang/Sema/SemaConsumer.h" 
- #include "clang/Serialization/ASTBitCodes.h" 
- #include "clang/Serialization/ASTDeserializationListener.h" 
- #include "clang/Serialization/PCHContainerOperations.h" 
- #include "clang/Serialization/SourceLocationEncoding.h" 
- #include "llvm/ADT/ArrayRef.h" 
- #include "llvm/ADT/DenseMap.h" 
- #include "llvm/ADT/DenseSet.h" 
- #include "llvm/ADT/MapVector.h" 
- #include "llvm/ADT/STLExtras.h" 
- #include "llvm/ADT/SetVector.h" 
- #include "llvm/ADT/SmallVector.h" 
- #include "llvm/ADT/StringRef.h" 
- #include "llvm/Bitstream/BitstreamWriter.h" 
- #include <cassert> 
- #include <cstddef> 
- #include <cstdint> 
- #include <ctime> 
- #include <memory> 
- #include <queue> 
- #include <string> 
- #include <utility> 
- #include <vector> 
-   
- namespace clang { 
-   
- class ASTContext; 
- class ASTReader; 
- class Attr; 
- class CXXRecordDecl; 
- class FileEntry; 
- class FPOptionsOverride; 
- class FunctionDecl; 
- class HeaderSearch; 
- class HeaderSearchOptions; 
- class IdentifierResolver; 
- class LangOptions; 
- class MacroDefinitionRecord; 
- class MacroInfo; 
- class Module; 
- class InMemoryModuleCache; 
- class ModuleFileExtension; 
- class ModuleFileExtensionWriter; 
- class NamedDecl; 
- class ObjCInterfaceDecl; 
- class PreprocessingRecord; 
- class Preprocessor; 
- class RecordDecl; 
- class Sema; 
- class SourceManager; 
- class Stmt; 
- class StoredDeclsList; 
- class SwitchCase; 
- class Token; 
-   
- /// Writes an AST file containing the contents of a translation unit. 
- /// 
- /// The ASTWriter class produces a bitstream containing the serialized 
- /// representation of a given abstract syntax tree and its supporting 
- /// data structures. This bitstream can be de-serialized via an 
- /// instance of the ASTReader class. 
- class ASTWriter : public ASTDeserializationListener, 
-                   public ASTMutationListener { 
- public: 
-   friend class ASTDeclWriter; 
-   friend class ASTRecordWriter; 
-   
-   using RecordData = SmallVector<uint64_t, 64>; 
-   using RecordDataImpl = SmallVectorImpl<uint64_t>; 
-   using RecordDataRef = ArrayRef<uint64_t>; 
-   
- private: 
-   /// Map that provides the ID numbers of each type within the 
-   /// output stream, plus those deserialized from a chained PCH. 
-   /// 
-   /// The ID numbers of types are consecutive (in order of discovery) 
-   /// and start at 1. 0 is reserved for NULL. When types are actually 
-   /// stored in the stream, the ID number is shifted by 2 bits to 
-   /// allow for the const/volatile qualifiers. 
-   /// 
-   /// Keys in the map never have const/volatile qualifiers. 
-   using TypeIdxMap = llvm::DenseMap<QualType, serialization::TypeIdx, 
-                                     serialization::UnsafeQualTypeDenseMapInfo>; 
-   
-   using LocSeq = SourceLocationSequence; 
-   
-   /// The bitstream writer used to emit this precompiled header. 
-   llvm::BitstreamWriter &Stream; 
-   
-   /// The buffer associated with the bitstream. 
-   const SmallVectorImpl<char> &Buffer; 
-   
-   /// The PCM manager which manages memory buffers for pcm files. 
-   InMemoryModuleCache &ModuleCache; 
-   
-   /// The ASTContext we're writing. 
-   ASTContext *Context = nullptr; 
-   
-   /// The preprocessor we're writing. 
-   Preprocessor *PP = nullptr; 
-   
-   /// The reader of existing AST files, if we're chaining. 
-   ASTReader *Chain = nullptr; 
-   
-   /// The module we're currently writing, if any. 
-   Module *WritingModule = nullptr; 
-   
-   /// The offset of the first bit inside the AST_BLOCK. 
-   uint64_t ASTBlockStartOffset = 0; 
-   
-   /// The range representing all the AST_BLOCK. 
-   std::pair<uint64_t, uint64_t> ASTBlockRange; 
-   
-   /// The base directory for any relative paths we emit. 
-   std::string BaseDirectory; 
-   
-   /// Indicates whether timestamps should be written to the produced 
-   /// module file. This is the case for files implicitly written to the 
-   /// module cache, where we need the timestamps to determine if the module 
-   /// file is up to date, but not otherwise. 
-   bool IncludeTimestamps; 
-   
-   /// Indicates when the AST writing is actively performing 
-   /// serialization, rather than just queueing updates. 
-   bool WritingAST = false; 
-   
-   /// Indicates that we are done serializing the collection of decls 
-   /// and types to emit. 
-   bool DoneWritingDeclsAndTypes = false; 
-   
-   /// Indicates that the AST contained compiler errors. 
-   bool ASTHasCompilerErrors = false; 
-   
-   /// Mapping from input file entries to the index into the 
-   /// offset table where information about that input file is stored. 
-   llvm::DenseMap<const FileEntry *, uint32_t> InputFileIDs; 
-   
-   /// Stores a declaration or a type to be written to the AST file. 
-   class DeclOrType { 
-   public: 
-     DeclOrType(Decl *D) : Stored(D), IsType(false) {} 
-     DeclOrType(QualType T) : Stored(T.getAsOpaquePtr()), IsType(true) {} 
-   
-     bool isType() const { return IsType; } 
-     bool isDecl() const { return !IsType; } 
-   
-     QualType getType() const { 
-       assert(isType() && "Not a type!"); 
-       return QualType::getFromOpaquePtr(Stored); 
-     } 
-   
-     Decl *getDecl() const { 
-       assert(isDecl() && "Not a decl!"); 
-       return static_cast<Decl *>(Stored); 
-     } 
-   
-   private: 
-     void *Stored; 
-     bool IsType; 
-   }; 
-   
-   /// The declarations and types to emit. 
-   std::queue<DeclOrType> DeclTypesToEmit; 
-   
-   /// The first ID number we can use for our own declarations. 
-   serialization::DeclID FirstDeclID = serialization::NUM_PREDEF_DECL_IDS; 
-   
-   /// The decl ID that will be assigned to the next new decl. 
-   serialization::DeclID NextDeclID = FirstDeclID; 
-   
-   /// Map that provides the ID numbers of each declaration within 
-   /// the output stream, as well as those deserialized from a chained PCH. 
-   /// 
-   /// The ID numbers of declarations are consecutive (in order of 
-   /// discovery) and start at 2. 1 is reserved for the translation 
-   /// unit, while 0 is reserved for NULL. 
-   llvm::DenseMap<const Decl *, serialization::DeclID> DeclIDs; 
-   
-   /// Offset of each declaration in the bitstream, indexed by 
-   /// the declaration's ID. 
-   std::vector<serialization::DeclOffset> DeclOffsets; 
-   
-   /// The offset of the DECLTYPES_BLOCK. The offsets in DeclOffsets 
-   /// are relative to this value. 
-   uint64_t DeclTypesBlockStartOffset = 0; 
-   
-   /// Sorted (by file offset) vector of pairs of file offset/DeclID. 
-   using LocDeclIDsTy = 
-       SmallVector<std::pair<unsigned, serialization::DeclID>, 64>; 
-   struct DeclIDInFileInfo { 
-     LocDeclIDsTy DeclIDs; 
-   
-     /// Set when the DeclIDs vectors from all files are joined, this 
-     /// indicates the index that this particular vector has in the global one. 
-     unsigned FirstDeclIndex; 
-   }; 
-   using FileDeclIDsTy = 
-       llvm::DenseMap<FileID, std::unique_ptr<DeclIDInFileInfo>>; 
-   
-   /// Map from file SLocEntries to info about the file-level declarations 
-   /// that it contains. 
-   FileDeclIDsTy FileDeclIDs; 
-   
-   void associateDeclWithFile(const Decl *D, serialization::DeclID); 
-   
-   /// The first ID number we can use for our own types. 
-   serialization::TypeID FirstTypeID = serialization::NUM_PREDEF_TYPE_IDS; 
-   
-   /// The type ID that will be assigned to the next new type. 
-   serialization::TypeID NextTypeID = FirstTypeID; 
-   
-   /// Map that provides the ID numbers of each type within the 
-   /// output stream, plus those deserialized from a chained PCH. 
-   /// 
-   /// The ID numbers of types are consecutive (in order of discovery) 
-   /// and start at 1. 0 is reserved for NULL. When types are actually 
-   /// stored in the stream, the ID number is shifted by 2 bits to 
-   /// allow for the const/volatile qualifiers. 
-   /// 
-   /// Keys in the map never have const/volatile qualifiers. 
-   TypeIdxMap TypeIdxs; 
-   
-   /// Offset of each type in the bitstream, indexed by 
-   /// the type's ID. 
-   std::vector<serialization::UnderalignedInt64> TypeOffsets; 
-   
-   /// The first ID number we can use for our own identifiers. 
-   serialization::IdentID FirstIdentID = serialization::NUM_PREDEF_IDENT_IDS; 
-   
-   /// The identifier ID that will be assigned to the next new identifier. 
-   serialization::IdentID NextIdentID = FirstIdentID; 
-   
-   /// Map that provides the ID numbers of each identifier in 
-   /// the output stream. 
-   /// 
-   /// The ID numbers for identifiers are consecutive (in order of 
-   /// discovery), starting at 1. An ID of zero refers to a NULL 
-   /// IdentifierInfo. 
-   llvm::MapVector<const IdentifierInfo *, serialization::IdentID> IdentifierIDs; 
-   
-   /// The first ID number we can use for our own macros. 
-   serialization::MacroID FirstMacroID = serialization::NUM_PREDEF_MACRO_IDS; 
-   
-   /// The identifier ID that will be assigned to the next new identifier. 
-   serialization::MacroID NextMacroID = FirstMacroID; 
-   
-   /// Map that provides the ID numbers of each macro. 
-   llvm::DenseMap<MacroInfo *, serialization::MacroID> MacroIDs; 
-   
-   struct MacroInfoToEmitData { 
-     const IdentifierInfo *Name; 
-     MacroInfo *MI; 
-     serialization::MacroID ID; 
-   }; 
-   
-   /// The macro infos to emit. 
-   std::vector<MacroInfoToEmitData> MacroInfosToEmit; 
-   
-   llvm::DenseMap<const IdentifierInfo *, uint32_t> 
-       IdentMacroDirectivesOffsetMap; 
-   
-   /// @name FlushStmt Caches 
-   /// @{ 
-   
-   /// Set of parent Stmts for the currently serializing sub-stmt. 
-   llvm::DenseSet<Stmt *> ParentStmts; 
-   
-   /// Offsets of sub-stmts already serialized. The offset points 
-   /// just after the stmt record. 
-   llvm::DenseMap<Stmt *, uint64_t> SubStmtEntries; 
-   
-   /// @} 
-   
-   /// Offsets of each of the identifier IDs into the identifier 
-   /// table. 
-   std::vector<uint32_t> IdentifierOffsets; 
-   
-   /// The first ID number we can use for our own submodules. 
-   serialization::SubmoduleID FirstSubmoduleID = 
-       serialization::NUM_PREDEF_SUBMODULE_IDS; 
-   
-   /// The submodule ID that will be assigned to the next new submodule. 
-   serialization::SubmoduleID NextSubmoduleID = FirstSubmoduleID; 
-   
-   /// The first ID number we can use for our own selectors. 
-   serialization::SelectorID FirstSelectorID = 
-       serialization::NUM_PREDEF_SELECTOR_IDS; 
-   
-   /// The selector ID that will be assigned to the next new selector. 
-   serialization::SelectorID NextSelectorID = FirstSelectorID; 
-   
-   /// Map that provides the ID numbers of each Selector. 
-   llvm::MapVector<Selector, serialization::SelectorID> SelectorIDs; 
-   
-   /// Offset of each selector within the method pool/selector 
-   /// table, indexed by the Selector ID (-1). 
-   std::vector<uint32_t> SelectorOffsets; 
-   
-   /// Mapping from macro definitions (as they occur in the preprocessing 
-   /// record) to the macro IDs. 
-   llvm::DenseMap<const MacroDefinitionRecord *, 
-                  serialization::PreprocessedEntityID> MacroDefinitions; 
-   
-   /// Cache of indices of anonymous declarations within their lexical 
-   /// contexts. 
-   llvm::DenseMap<const Decl *, unsigned> AnonymousDeclarationNumbers; 
-   
-   /// An update to a Decl. 
-   class DeclUpdate { 
-     /// A DeclUpdateKind. 
-     unsigned Kind; 
-     union { 
-       const Decl *Dcl; 
-       void *Type; 
-       SourceLocation::UIntTy Loc; 
-       unsigned Val; 
-       Module *Mod; 
-       const Attr *Attribute; 
-     }; 
-   
-   public: 
-     DeclUpdate(unsigned Kind) : Kind(Kind), Dcl(nullptr) {} 
-     DeclUpdate(unsigned Kind, const Decl *Dcl) : Kind(Kind), Dcl(Dcl) {} 
-     DeclUpdate(unsigned Kind, QualType Type) 
-         : Kind(Kind), Type(Type.getAsOpaquePtr()) {} 
-     DeclUpdate(unsigned Kind, SourceLocation Loc) 
-         : Kind(Kind), Loc(Loc.getRawEncoding()) {} 
-     DeclUpdate(unsigned Kind, unsigned Val) : Kind(Kind), Val(Val) {} 
-     DeclUpdate(unsigned Kind, Module *M) : Kind(Kind), Mod(M) {} 
-     DeclUpdate(unsigned Kind, const Attr *Attribute) 
-           : Kind(Kind), Attribute(Attribute) {} 
-   
-     unsigned getKind() const { return Kind; } 
-     const Decl *getDecl() const { return Dcl; } 
-     QualType getType() const { return QualType::getFromOpaquePtr(Type); } 
-   
-     SourceLocation getLoc() const { 
-       return SourceLocation::getFromRawEncoding(Loc); 
-     } 
-   
-     unsigned getNumber() const { return Val; } 
-     Module *getModule() const { return Mod; } 
-     const Attr *getAttr() const { return Attribute; } 
-   }; 
-   
-   using UpdateRecord = SmallVector<DeclUpdate, 1>; 
-   using DeclUpdateMap = llvm::MapVector<const Decl *, UpdateRecord>; 
-   
-   /// Mapping from declarations that came from a chained PCH to the 
-   /// record containing modifications to them. 
-   DeclUpdateMap DeclUpdates; 
-   
-   using FirstLatestDeclMap = llvm::DenseMap<Decl *, Decl *>; 
-   
-   /// Map of first declarations from a chained PCH that point to the 
-   /// most recent declarations in another PCH. 
-   FirstLatestDeclMap FirstLatestDecls; 
-   
-   /// Declarations encountered that might be external 
-   /// definitions. 
-   /// 
-   /// We keep track of external definitions and other 'interesting' declarations 
-   /// as we are emitting declarations to the AST file. The AST file contains a 
-   /// separate record for these declarations, which are provided to the AST 
-   /// consumer by the AST reader. This is behavior is required to properly cope with, 
-   /// e.g., tentative variable definitions that occur within 
-   /// headers. The declarations themselves are stored as declaration 
-   /// IDs, since they will be written out to an EAGERLY_DESERIALIZED_DECLS 
-   /// record. 
-   SmallVector<serialization::DeclID, 16> EagerlyDeserializedDecls; 
-   SmallVector<serialization::DeclID, 16> ModularCodegenDecls; 
-   
-   /// DeclContexts that have received extensions since their serialized 
-   /// form. 
-   /// 
-   /// For namespaces, when we're chaining and encountering a namespace, we check 
-   /// if its primary namespace comes from the chain. If it does, we add the 
-   /// primary to this set, so that we can write out lexical content updates for 
-   /// it. 
-   llvm::SmallSetVector<const DeclContext *, 16> UpdatedDeclContexts; 
-   
-   /// Keeps track of declarations that we must emit, even though we're 
-   /// not guaranteed to be able to find them by walking the AST starting at the 
-   /// translation unit. 
-   SmallVector<const Decl *, 16> DeclsToEmitEvenIfUnreferenced; 
-   
-   /// The set of Objective-C class that have categories we 
-   /// should serialize. 
-   llvm::SetVector<ObjCInterfaceDecl *> ObjCClassesWithCategories; 
-   
-   /// The set of declarations that may have redeclaration chains that 
-   /// need to be serialized. 
-   llvm::SmallVector<const Decl *, 16> Redeclarations; 
-   
-   /// A cache of the first local declaration for "interesting" 
-   /// redeclaration chains. 
-   llvm::DenseMap<const Decl *, const Decl *> FirstLocalDeclCache; 
-   
-   /// Mapping from SwitchCase statements to IDs. 
-   llvm::DenseMap<SwitchCase *, unsigned> SwitchCaseIDs; 
-   
-   /// The number of statements written to the AST file. 
-   unsigned NumStatements = 0; 
-   
-   /// The number of macros written to the AST file. 
-   unsigned NumMacros = 0; 
-   
-   /// The number of lexical declcontexts written to the AST 
-   /// file. 
-   unsigned NumLexicalDeclContexts = 0; 
-   
-   /// The number of visible declcontexts written to the AST 
-   /// file. 
-   unsigned NumVisibleDeclContexts = 0; 
-   
-   /// A mapping from each known submodule to its ID number, which will 
-   /// be a positive integer. 
-   llvm::DenseMap<const Module *, unsigned> SubmoduleIDs; 
-   
-   /// A list of the module file extension writers. 
-   std::vector<std::unique_ptr<ModuleFileExtensionWriter>> 
-       ModuleFileExtensionWriters; 
-   
-   /// Mapping from a source location entry to whether it is affecting or not. 
-   llvm::BitVector IsSLocAffecting; 
-   
-   /// Mapping from \c FileID to an index into the FileID adjustment table. 
-   std::vector<FileID> NonAffectingFileIDs; 
-   std::vector<unsigned> NonAffectingFileIDAdjustments; 
-   
-   /// Mapping from an offset to an index into the offset adjustment table. 
-   std::vector<SourceRange> NonAffectingRanges; 
-   std::vector<SourceLocation::UIntTy> NonAffectingOffsetAdjustments; 
-   
-   /// Collects input files that didn't affect compilation of the current module, 
-   /// and initializes data structures necessary for leaving those files out 
-   /// during \c SourceManager serialization. 
-   void collectNonAffectingInputFiles(); 
-   
-   /// Returns an adjusted \c FileID, accounting for any non-affecting input 
-   /// files. 
-   FileID getAdjustedFileID(FileID FID) const; 
-   /// Returns an adjusted number of \c FileIDs created within the specified \c 
-   /// FileID, accounting for any non-affecting input files. 
-   unsigned getAdjustedNumCreatedFIDs(FileID FID) const; 
-   /// Returns an adjusted \c SourceLocation, accounting for any non-affecting 
-   /// input files. 
-   SourceLocation getAdjustedLocation(SourceLocation Loc) const; 
-   /// Returns an adjusted \c SourceRange, accounting for any non-affecting input 
-   /// files. 
-   SourceRange getAdjustedRange(SourceRange Range) const; 
-   /// Returns an adjusted \c SourceLocation offset, accounting for any 
-   /// non-affecting input files. 
-   SourceLocation::UIntTy getAdjustedOffset(SourceLocation::UIntTy Offset) const; 
-   /// Returns an adjustment for offset into SourceManager, accounting for any 
-   /// non-affecting input files. 
-   SourceLocation::UIntTy getAdjustment(SourceLocation::UIntTy Offset) const; 
-   
-   /// Retrieve or create a submodule ID for this module. 
-   unsigned getSubmoduleID(Module *Mod); 
-   
-   /// Write the given subexpression to the bitstream. 
-   void WriteSubStmt(Stmt *S); 
-   
-   void WriteBlockInfoBlock(); 
-   void WriteControlBlock(Preprocessor &PP, ASTContext &Context, 
-                          StringRef isysroot); 
-   
-   /// Write out the signature and diagnostic options, and return the signature. 
-   ASTFileSignature writeUnhashedControlBlock(Preprocessor &PP, 
-                                              ASTContext &Context); 
-   
-   /// Calculate hash of the pcm content. 
-   static std::pair<ASTFileSignature, ASTFileSignature> 
-   createSignature(StringRef AllBytes, StringRef ASTBlockBytes); 
-   
-   void WriteInputFiles(SourceManager &SourceMgr, HeaderSearchOptions &HSOpts); 
-   void WriteSourceManagerBlock(SourceManager &SourceMgr, 
-                                const Preprocessor &PP); 
-   void writeIncludedFiles(raw_ostream &Out, const Preprocessor &PP); 
-   void WritePreprocessor(const Preprocessor &PP, bool IsModule); 
-   void WriteHeaderSearch(const HeaderSearch &HS); 
-   void WritePreprocessorDetail(PreprocessingRecord &PPRec, 
-                                uint64_t MacroOffsetsBase); 
-   void WriteSubmodules(Module *WritingModule); 
-   
-   void WritePragmaDiagnosticMappings(const DiagnosticsEngine &Diag, 
-                                      bool isModule); 
-   
-   unsigned TypeExtQualAbbrev = 0; 
-   void WriteTypeAbbrevs(); 
-   void WriteType(QualType T); 
-   
-   bool isLookupResultExternal(StoredDeclsList &Result, DeclContext *DC); 
-   bool isLookupResultEntirelyExternal(StoredDeclsList &Result, DeclContext *DC); 
-   
-   void GenerateNameLookupTable(const DeclContext *DC, 
-                                llvm::SmallVectorImpl<char> &LookupTable); 
-   uint64_t WriteDeclContextLexicalBlock(ASTContext &Context, DeclContext *DC); 
-   uint64_t WriteDeclContextVisibleBlock(ASTContext &Context, DeclContext *DC); 
-   void WriteTypeDeclOffsets(); 
-   void WriteFileDeclIDsMap(); 
-   void WriteComments(); 
-   void WriteSelectors(Sema &SemaRef); 
-   void WriteReferencedSelectorsPool(Sema &SemaRef); 
-   void WriteIdentifierTable(Preprocessor &PP, IdentifierResolver &IdResolver, 
-                             bool IsModule); 
-   void WriteDeclUpdatesBlocks(RecordDataImpl &OffsetsRecord); 
-   void WriteDeclContextVisibleUpdate(const DeclContext *DC); 
-   void WriteFPPragmaOptions(const FPOptionsOverride &Opts); 
-   void WriteOpenCLExtensions(Sema &SemaRef); 
-   void WriteCUDAPragmas(Sema &SemaRef); 
-   void WriteObjCCategories(); 
-   void WriteLateParsedTemplates(Sema &SemaRef); 
-   void WriteOptimizePragmaOptions(Sema &SemaRef); 
-   void WriteMSStructPragmaOptions(Sema &SemaRef); 
-   void WriteMSPointersToMembersPragmaOptions(Sema &SemaRef); 
-   void WritePackPragmaOptions(Sema &SemaRef); 
-   void WriteFloatControlPragmaOptions(Sema &SemaRef); 
-   void WriteModuleFileExtension(Sema &SemaRef, 
-                                 ModuleFileExtensionWriter &Writer); 
-   
-   unsigned DeclParmVarAbbrev = 0; 
-   unsigned DeclContextLexicalAbbrev = 0; 
-   unsigned DeclContextVisibleLookupAbbrev = 0; 
-   unsigned UpdateVisibleAbbrev = 0; 
-   unsigned DeclRecordAbbrev = 0; 
-   unsigned DeclTypedefAbbrev = 0; 
-   unsigned DeclVarAbbrev = 0; 
-   unsigned DeclFieldAbbrev = 0; 
-   unsigned DeclEnumAbbrev = 0; 
-   unsigned DeclObjCIvarAbbrev = 0; 
-   unsigned DeclCXXMethodAbbrev = 0; 
-   
-   unsigned DeclRefExprAbbrev = 0; 
-   unsigned CharacterLiteralAbbrev = 0; 
-   unsigned IntegerLiteralAbbrev = 0; 
-   unsigned ExprImplicitCastAbbrev = 0; 
-   
-   void WriteDeclAbbrevs(); 
-   void WriteDecl(ASTContext &Context, Decl *D); 
-   
-   ASTFileSignature WriteASTCore(Sema &SemaRef, StringRef isysroot, 
-                                 Module *WritingModule); 
-   
- public: 
-   /// Create a new precompiled header writer that outputs to 
-   /// the given bitstream. 
-   ASTWriter(llvm::BitstreamWriter &Stream, SmallVectorImpl<char> &Buffer, 
-             InMemoryModuleCache &ModuleCache, 
-             ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions, 
-             bool IncludeTimestamps = true); 
-   ~ASTWriter() override; 
-   
-   ASTContext &getASTContext() const { 
-     assert(Context && "requested AST context when not writing AST"); 
-     return *Context; 
-   } 
-   
-   const LangOptions &getLangOpts() const; 
-   
-   /// Get a timestamp for output into the AST file. The actual timestamp 
-   /// of the specified file may be ignored if we have been instructed to not 
-   /// include timestamps in the output file. 
-   time_t getTimestampForOutput(const FileEntry *E) const; 
-   
-   /// Write a precompiled header for the given semantic analysis. 
-   /// 
-   /// \param SemaRef a reference to the semantic analysis object that processed 
-   /// the AST to be written into the precompiled header. 
-   /// 
-   /// \param WritingModule The module that we are writing. If null, we are 
-   /// writing a precompiled header. 
-   /// 
-   /// \param isysroot if non-empty, write a relocatable file whose headers 
-   /// are relative to the given system root. If we're writing a module, its 
-   /// build directory will be used in preference to this if both are available. 
-   /// 
-   /// \return the module signature, which eventually will be a hash of 
-   /// the module but currently is merely a random 32-bit number. 
-   ASTFileSignature WriteAST(Sema &SemaRef, StringRef OutputFile, 
-                             Module *WritingModule, StringRef isysroot, 
-                             bool hasErrors = false, 
-                             bool ShouldCacheASTInMemory = false); 
-   
-   /// Emit a token. 
-   void AddToken(const Token &Tok, RecordDataImpl &Record); 
-   
-   /// Emit a AlignPackInfo. 
-   void AddAlignPackInfo(const Sema::AlignPackInfo &Info, 
-                         RecordDataImpl &Record); 
-   
-   /// Emit a FileID. 
-   void AddFileID(FileID FID, RecordDataImpl &Record); 
-   
-   /// Emit a source location. 
-   void AddSourceLocation(SourceLocation Loc, RecordDataImpl &Record, 
-                          LocSeq *Seq = nullptr); 
-   
-   /// Emit a source range. 
-   void AddSourceRange(SourceRange Range, RecordDataImpl &Record, 
-                       LocSeq *Seq = nullptr); 
-   
-   /// Emit a reference to an identifier. 
-   void AddIdentifierRef(const IdentifierInfo *II, RecordDataImpl &Record); 
-   
-   /// Get the unique number used to refer to the given selector. 
-   serialization::SelectorID getSelectorRef(Selector Sel); 
-   
-   /// Get the unique number used to refer to the given identifier. 
-   serialization::IdentID getIdentifierRef(const IdentifierInfo *II); 
-   
-   /// Get the unique number used to refer to the given macro. 
-   serialization::MacroID getMacroRef(MacroInfo *MI, const IdentifierInfo *Name); 
-   
-   /// Determine the ID of an already-emitted macro. 
-   serialization::MacroID getMacroID(MacroInfo *MI); 
-   
-   uint32_t getMacroDirectivesOffset(const IdentifierInfo *Name); 
-   
-   /// Emit a reference to a type. 
-   void AddTypeRef(QualType T, RecordDataImpl &Record); 
-   
-   /// Force a type to be emitted and get its ID. 
-   serialization::TypeID GetOrCreateTypeID(QualType T); 
-   
-   /// Determine the type ID of an already-emitted type. 
-   serialization::TypeID getTypeID(QualType T) const; 
-   
-   /// Find the first local declaration of a given local redeclarable 
-   /// decl. 
-   const Decl *getFirstLocalDecl(const Decl *D); 
-   
-   /// Is this a local declaration (that is, one that will be written to 
-   /// our AST file)? This is the case for declarations that are neither imported 
-   /// from another AST file nor predefined. 
-   bool IsLocalDecl(const Decl *D) { 
-     if (D->isFromASTFile()) 
-       return false; 
-     auto I = DeclIDs.find(D); 
-     return (I == DeclIDs.end() || 
-             I->second >= serialization::NUM_PREDEF_DECL_IDS); 
-   }; 
-   
-   /// Emit a reference to a declaration. 
-   void AddDeclRef(const Decl *D, RecordDataImpl &Record); 
-   
-   /// Force a declaration to be emitted and get its ID. 
-   serialization::DeclID GetDeclRef(const Decl *D); 
-   
-   /// Determine the declaration ID of an already-emitted 
-   /// declaration. 
-   serialization::DeclID getDeclID(const Decl *D); 
-   
-   unsigned getAnonymousDeclarationNumber(const NamedDecl *D); 
-   
-   /// Add a string to the given record. 
-   void AddString(StringRef Str, RecordDataImpl &Record); 
-   
-   /// Convert a path from this build process into one that is appropriate 
-   /// for emission in the module file. 
-   bool PreparePathForOutput(SmallVectorImpl<char> &Path); 
-   
-   /// Add a path to the given record. 
-   void AddPath(StringRef Path, RecordDataImpl &Record); 
-   
-   /// Emit the current record with the given path as a blob. 
-   void EmitRecordWithPath(unsigned Abbrev, RecordDataRef Record, 
-                           StringRef Path); 
-   
-   /// Add a version tuple to the given record 
-   void AddVersionTuple(const VersionTuple &Version, RecordDataImpl &Record); 
-   
-   /// Retrieve or create a submodule ID for this module, or return 0 if 
-   /// the submodule is neither local (a submodle of the currently-written module) 
-   /// nor from an imported module. 
-   unsigned getLocalOrImportedSubmoduleID(const Module *Mod); 
-   
-   /// Note that the identifier II occurs at the given offset 
-   /// within the identifier table. 
-   void SetIdentifierOffset(const IdentifierInfo *II, uint32_t Offset); 
-   
-   /// Note that the selector Sel occurs at the given offset 
-   /// within the method pool/selector table. 
-   void SetSelectorOffset(Selector Sel, uint32_t Offset); 
-   
-   /// Record an ID for the given switch-case statement. 
-   unsigned RecordSwitchCaseID(SwitchCase *S); 
-   
-   /// Retrieve the ID for the given switch-case statement. 
-   unsigned getSwitchCaseID(SwitchCase *S); 
-   
-   void ClearSwitchCaseIDs(); 
-   
-   unsigned getTypeExtQualAbbrev() const { 
-     return TypeExtQualAbbrev; 
-   } 
-   
-   unsigned getDeclParmVarAbbrev() const { return DeclParmVarAbbrev; } 
-   unsigned getDeclRecordAbbrev() const { return DeclRecordAbbrev; } 
-   unsigned getDeclTypedefAbbrev() const { return DeclTypedefAbbrev; } 
-   unsigned getDeclVarAbbrev() const { return DeclVarAbbrev; } 
-   unsigned getDeclFieldAbbrev() const { return DeclFieldAbbrev; } 
-   unsigned getDeclEnumAbbrev() const { return DeclEnumAbbrev; } 
-   unsigned getDeclObjCIvarAbbrev() const { return DeclObjCIvarAbbrev; } 
-   unsigned getDeclCXXMethodAbbrev() const { return DeclCXXMethodAbbrev; } 
-   
-   unsigned getDeclRefExprAbbrev() const { return DeclRefExprAbbrev; } 
-   unsigned getCharacterLiteralAbbrev() const { return CharacterLiteralAbbrev; } 
-   unsigned getIntegerLiteralAbbrev() const { return IntegerLiteralAbbrev; } 
-   unsigned getExprImplicitCastAbbrev() const { return ExprImplicitCastAbbrev; } 
-   
-   bool hasChain() const { return Chain; } 
-   ASTReader *getChain() const { return Chain; } 
-   
-   bool isWritingStdCXXNamedModules() const { 
-     return WritingModule && WritingModule->isModulePurview(); 
-   } 
-   
- private: 
-   // ASTDeserializationListener implementation 
-   void ReaderInitialized(ASTReader *Reader) override; 
-   void IdentifierRead(serialization::IdentID ID, IdentifierInfo *II) override; 
-   void MacroRead(serialization::MacroID ID, MacroInfo *MI) override; 
-   void TypeRead(serialization::TypeIdx Idx, QualType T) override; 
-   void SelectorRead(serialization::SelectorID ID, Selector Sel) override; 
-   void MacroDefinitionRead(serialization::PreprocessedEntityID ID, 
-                            MacroDefinitionRecord *MD) override; 
-   void ModuleRead(serialization::SubmoduleID ID, Module *Mod) override; 
-   
-   // ASTMutationListener implementation. 
-   void CompletedTagDefinition(const TagDecl *D) override; 
-   void AddedVisibleDecl(const DeclContext *DC, const Decl *D) override; 
-   void AddedCXXImplicitMember(const CXXRecordDecl *RD, const Decl *D) override; 
-   void AddedCXXTemplateSpecialization( 
-       const ClassTemplateDecl *TD, 
-       const ClassTemplateSpecializationDecl *D) override; 
-   void AddedCXXTemplateSpecialization( 
-       const VarTemplateDecl *TD, 
-       const VarTemplateSpecializationDecl *D) override; 
-   void AddedCXXTemplateSpecialization(const FunctionTemplateDecl *TD, 
-                                       const FunctionDecl *D) override; 
-   void ResolvedExceptionSpec(const FunctionDecl *FD) override; 
-   void DeducedReturnType(const FunctionDecl *FD, QualType ReturnType) override; 
-   void ResolvedOperatorDelete(const CXXDestructorDecl *DD, 
-                               const FunctionDecl *Delete, 
-                               Expr *ThisArg) override; 
-   void CompletedImplicitDefinition(const FunctionDecl *D) override; 
-   void InstantiationRequested(const ValueDecl *D) override; 
-   void VariableDefinitionInstantiated(const VarDecl *D) override; 
-   void FunctionDefinitionInstantiated(const FunctionDecl *D) override; 
-   void DefaultArgumentInstantiated(const ParmVarDecl *D) override; 
-   void DefaultMemberInitializerInstantiated(const FieldDecl *D) override; 
-   void AddedObjCCategoryToInterface(const ObjCCategoryDecl *CatD, 
-                                     const ObjCInterfaceDecl *IFD) override; 
-   void DeclarationMarkedUsed(const Decl *D) override; 
-   void DeclarationMarkedOpenMPThreadPrivate(const Decl *D) override; 
-   void DeclarationMarkedOpenMPDeclareTarget(const Decl *D, 
-                                             const Attr *Attr) override; 
-   void DeclarationMarkedOpenMPAllocate(const Decl *D, const Attr *A) override; 
-   void RedefinedHiddenDefinition(const NamedDecl *D, Module *M) override; 
-   void AddedAttributeToRecord(const Attr *Attr, 
-                               const RecordDecl *Record) override; 
- }; 
-   
- /// AST and semantic-analysis consumer that generates a 
- /// precompiled header from the parsed source code. 
- class PCHGenerator : public SemaConsumer { 
-   const Preprocessor &PP; 
-   std::string OutputFile; 
-   std::string isysroot; 
-   Sema *SemaPtr; 
-   std::shared_ptr<PCHBuffer> Buffer; 
-   llvm::BitstreamWriter Stream; 
-   ASTWriter Writer; 
-   bool AllowASTWithErrors; 
-   bool ShouldCacheASTInMemory; 
-   
- protected: 
-   ASTWriter &getWriter() { return Writer; } 
-   const ASTWriter &getWriter() const { return Writer; } 
-   SmallVectorImpl<char> &getPCH() const { return Buffer->Data; } 
-   
- public: 
-   PCHGenerator(const Preprocessor &PP, InMemoryModuleCache &ModuleCache, 
-                StringRef OutputFile, StringRef isysroot, 
-                std::shared_ptr<PCHBuffer> Buffer, 
-                ArrayRef<std::shared_ptr<ModuleFileExtension>> Extensions, 
-                bool AllowASTWithErrors = false, bool IncludeTimestamps = true, 
-                bool ShouldCacheASTInMemory = false); 
-   ~PCHGenerator() override; 
-   
-   void InitializeSema(Sema &S) override { SemaPtr = &S; } 
-   void HandleTranslationUnit(ASTContext &Ctx) override; 
-   ASTMutationListener *GetASTMutationListener() override; 
-   ASTDeserializationListener *GetASTDeserializationListener() override; 
-   bool hasEmittedPCH() const { return Buffer->IsComplete; } 
- }; 
-   
- } // namespace clang 
-   
- #endif // LLVM_CLANG_SERIALIZATION_ASTWRITER_H 
-