//===- Preprocessor.h - C Language Family Preprocessor ----------*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
/// \file
 
/// Defines the clang::Preprocessor interface.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_LEX_PREPROCESSOR_H
 
#define LLVM_CLANG_LEX_PREPROCESSOR_H
 
 
 
#include "clang/Basic/Diagnostic.h"
 
#include "clang/Basic/DiagnosticIDs.h"
 
#include "clang/Basic/IdentifierTable.h"
 
#include "clang/Basic/LLVM.h"
 
#include "clang/Basic/LangOptions.h"
 
#include "clang/Basic/Module.h"
 
#include "clang/Basic/SourceLocation.h"
 
#include "clang/Basic/SourceManager.h"
 
#include "clang/Basic/TokenKinds.h"
 
#include "clang/Lex/HeaderSearch.h"
 
#include "clang/Lex/Lexer.h"
 
#include "clang/Lex/MacroInfo.h"
 
#include "clang/Lex/ModuleLoader.h"
 
#include "clang/Lex/ModuleMap.h"
 
#include "clang/Lex/PPCallbacks.h"
 
#include "clang/Lex/Token.h"
 
#include "clang/Lex/TokenLexer.h"
 
#include "llvm/ADT/ArrayRef.h"
 
#include "llvm/ADT/DenseMap.h"
 
#include "llvm/ADT/FoldingSet.h"
 
#include "llvm/ADT/FunctionExtras.h"
 
#include "llvm/ADT/PointerUnion.h"
 
#include "llvm/ADT/STLExtras.h"
 
#include "llvm/ADT/SmallPtrSet.h"
 
#include "llvm/ADT/SmallVector.h"
 
#include "llvm/ADT/StringRef.h"
 
#include "llvm/ADT/TinyPtrVector.h"
 
#include "llvm/ADT/iterator_range.h"
 
#include "llvm/Support/Allocator.h"
 
#include "llvm/Support/Casting.h"
 
#include "llvm/Support/Registry.h"
 
#include <cassert>
 
#include <cstddef>
 
#include <cstdint>
 
#include <map>
 
#include <memory>
 
#include <optional>
 
#include <string>
 
#include <utility>
 
#include <vector>
 
 
 
namespace llvm {
 
 
 
template<unsigned InternalLen> class SmallString;
 
 
 
} // namespace llvm
 
 
 
namespace clang {
 
 
 
class CodeCompletionHandler;
 
class CommentHandler;
 
class DirectoryEntry;
 
class EmptylineHandler;
 
class ExternalPreprocessorSource;
 
class FileEntry;
 
class FileManager;
 
class HeaderSearch;
 
class MacroArgs;
 
class PragmaHandler;
 
class PragmaNamespace;
 
class PreprocessingRecord;
 
class PreprocessorLexer;
 
class PreprocessorOptions;
 
class ScratchBuffer;
 
class TargetInfo;
 
 
 
namespace Builtin {
 
class Context;
 
}
 
 
 
/// Stores token information for comparing actual tokens with
 
/// predefined values.  Only handles simple tokens and identifiers.
 
class TokenValue {
 
  tok::TokenKind Kind;
 
  IdentifierInfo *II;
 
 
 
public:
 
  TokenValue(tok::TokenKind Kind) : Kind(Kind), II(nullptr) {
 
    assert(Kind != tok::raw_identifier && "Raw identifiers are not supported.");
 
    assert(Kind != tok::identifier &&
 
           "Identifiers should be created by TokenValue(IdentifierInfo *)");
 
    assert(!tok::isLiteral(Kind) && "Literals are not supported.");
 
    assert(!tok::isAnnotation(Kind) && "Annotations are not supported.");
 
  }
 
 
 
  TokenValue(IdentifierInfo *II) : Kind(tok::identifier), II(II) {}
 
 
 
  bool operator==(const Token &Tok) const {
 
    return Tok.getKind() == Kind &&
 
        (!II || II == Tok.getIdentifierInfo());
 
  }
 
};
 
 
 
/// Context in which macro name is used.
 
enum MacroUse {
 
  // other than #define or #undef
 
  MU_Other  = 0,
 
 
 
  // macro name specified in #define
 
  MU_Define = 1,
 
 
 
  // macro name specified in #undef
 
  MU_Undef  = 2
 
};
 
 
 
/// Engages in a tight little dance with the lexer to efficiently
 
/// preprocess tokens.
 
///
 
/// Lexers know only about tokens within a single source file, and don't
 
/// know anything about preprocessor-level issues like the \#include stack,
 
/// token expansion, etc.
 
class Preprocessor {
 
  friend class VAOptDefinitionContext;
 
  friend class VariadicMacroScopeGuard;
 
 
 
  llvm::unique_function<void(const clang::Token &)> OnToken;
 
  std::shared_ptr<PreprocessorOptions> PPOpts;
 
  DiagnosticsEngine        *Diags;
 
  LangOptions       &LangOpts;
 
  const TargetInfo *Target = nullptr;
 
  const TargetInfo *AuxTarget = nullptr;
 
  FileManager       &FileMgr;
 
  SourceManager     &SourceMgr;
 
  std::unique_ptr<ScratchBuffer> ScratchBuf;
 
  HeaderSearch      &HeaderInfo;
 
  ModuleLoader      &TheModuleLoader;
 
 
 
  /// External source of macros.
 
  ExternalPreprocessorSource *ExternalSource;
 
 
 
  /// A BumpPtrAllocator object used to quickly allocate and release
 
  /// objects internal to the Preprocessor.
 
  llvm::BumpPtrAllocator BP;
 
 
 
  /// Identifiers for builtin macros and other builtins.
 
  IdentifierInfo *Ident__LINE__, *Ident__FILE__;   // __LINE__, __FILE__
 
  IdentifierInfo *Ident__DATE__, *Ident__TIME__;   // __DATE__, __TIME__
 
  IdentifierInfo *Ident__INCLUDE_LEVEL__;          // __INCLUDE_LEVEL__
 
  IdentifierInfo *Ident__BASE_FILE__;              // __BASE_FILE__
 
  IdentifierInfo *Ident__FILE_NAME__;              // __FILE_NAME__
 
  IdentifierInfo *Ident__TIMESTAMP__;              // __TIMESTAMP__
 
  IdentifierInfo *Ident__COUNTER__;                // __COUNTER__
 
  IdentifierInfo *Ident_Pragma, *Ident__pragma;    // _Pragma, __pragma
 
  IdentifierInfo *Ident__identifier;               // __identifier
 
  IdentifierInfo *Ident__VA_ARGS__;                // __VA_ARGS__
 
  IdentifierInfo *Ident__VA_OPT__;                 // __VA_OPT__
 
  IdentifierInfo *Ident__has_feature;              // __has_feature
 
  IdentifierInfo *Ident__has_extension;            // __has_extension
 
  IdentifierInfo *Ident__has_builtin;              // __has_builtin
 
  IdentifierInfo *Ident__has_constexpr_builtin;    // __has_constexpr_builtin
 
  IdentifierInfo *Ident__has_attribute;            // __has_attribute
 
  IdentifierInfo *Ident__has_include;              // __has_include
 
  IdentifierInfo *Ident__has_include_next;         // __has_include_next
 
  IdentifierInfo *Ident__has_warning;              // __has_warning
 
  IdentifierInfo *Ident__is_identifier;            // __is_identifier
 
  IdentifierInfo *Ident__building_module;          // __building_module
 
  IdentifierInfo *Ident__MODULE__;                 // __MODULE__
 
  IdentifierInfo *Ident__has_cpp_attribute;        // __has_cpp_attribute
 
  IdentifierInfo *Ident__has_c_attribute;          // __has_c_attribute
 
  IdentifierInfo *Ident__has_declspec;             // __has_declspec_attribute
 
  IdentifierInfo *Ident__is_target_arch;           // __is_target_arch
 
  IdentifierInfo *Ident__is_target_vendor;         // __is_target_vendor
 
  IdentifierInfo *Ident__is_target_os;             // __is_target_os
 
  IdentifierInfo *Ident__is_target_environment;    // __is_target_environment
 
  IdentifierInfo *Ident__is_target_variant_os;
 
  IdentifierInfo *Ident__is_target_variant_environment;
 
  IdentifierInfo *Ident__FLT_EVAL_METHOD__;        // __FLT_EVAL_METHOD
 
 
 
  // Weak, only valid (and set) while InMacroArgs is true.
 
  Token* ArgMacro;
 
 
 
  SourceLocation DATELoc, TIMELoc;
 
 
 
  // FEM_UnsetOnCommandLine means that an explicit evaluation method was
 
  // not specified on the command line. The target is queried to set the
 
  // default evaluation method.
 
  LangOptions::FPEvalMethodKind CurrentFPEvalMethod =
 
      LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine;
 
 
 
  // The most recent pragma location where the floating point evaluation
 
  // method was modified. This is used to determine whether the
 
  // 'pragma clang fp eval_method' was used whithin the current scope.
 
  SourceLocation LastFPEvalPragmaLocation;
 
 
 
  LangOptions::FPEvalMethodKind TUFPEvalMethod =
 
      LangOptions::FPEvalMethodKind::FEM_UnsetOnCommandLine;
 
 
 
  // Next __COUNTER__ value, starts at 0.
 
  unsigned CounterValue = 0;
 
 
 
  enum {
 
    /// Maximum depth of \#includes.
 
    MaxAllowedIncludeStackDepth = 200
 
  };
 
 
 
  // State that is set before the preprocessor begins.
 
  bool KeepComments : 1;
 
  bool KeepMacroComments : 1;
 
  bool SuppressIncludeNotFoundError : 1;
 
 
 
  // State that changes while the preprocessor runs:
 
  bool InMacroArgs : 1;            // True if parsing fn macro invocation args.
 
 
 
  /// Whether the preprocessor owns the header search object.
 
  bool OwnsHeaderSearch : 1;
 
 
 
  /// True if macro expansion is disabled.
 
  bool DisableMacroExpansion : 1;
 
 
 
  /// Temporarily disables DisableMacroExpansion (i.e. enables expansion)
 
  /// when parsing preprocessor directives.
 
  bool MacroExpansionInDirectivesOverride : 1;
 
 
 
  class ResetMacroExpansionHelper;
 
 
 
  /// Whether we have already loaded macros from the external source.
 
  mutable bool ReadMacrosFromExternalSource : 1;
 
 
 
  /// True if pragmas are enabled.
 
  bool PragmasEnabled : 1;
 
 
 
  /// True if the current build action is a preprocessing action.
 
  bool PreprocessedOutput : 1;
 
 
 
  /// True if we are currently preprocessing a #if or #elif directive
 
  bool ParsingIfOrElifDirective;
 
 
 
  /// True if we are pre-expanding macro arguments.
 
  bool InMacroArgPreExpansion;
 
 
 
  /// Mapping/lookup information for all identifiers in
 
  /// the program, including program keywords.
 
  mutable IdentifierTable Identifiers;
 
 
 
  /// This table contains all the selectors in the program.
 
  ///
 
  /// Unlike IdentifierTable above, this table *isn't* populated by the
 
  /// preprocessor. It is declared/expanded here because its role/lifetime is
 
  /// conceptually similar to the IdentifierTable. In addition, the current
 
  /// control flow (in clang::ParseAST()), make it convenient to put here.
 
  ///
 
  /// FIXME: Make sure the lifetime of Identifiers/Selectors *isn't* tied to
 
  /// the lifetime of the preprocessor.
 
  SelectorTable Selectors;
 
 
 
  /// Information about builtins.
 
  std::unique_ptr<Builtin::Context> BuiltinInfo;
 
 
 
  /// Tracks all of the pragmas that the client registered
 
  /// with this preprocessor.
 
  std::unique_ptr<PragmaNamespace> PragmaHandlers;
 
 
 
  /// Pragma handlers of the original source is stored here during the
 
  /// parsing of a model file.
 
  std::unique_ptr<PragmaNamespace> PragmaHandlersBackup;
 
 
 
  /// Tracks all of the comment handlers that the client registered
 
  /// with this preprocessor.
 
  std::vector<CommentHandler *> CommentHandlers;
 
 
 
  /// Empty line handler.
 
  EmptylineHandler *Emptyline = nullptr;
 
 
 
public:
 
  /// The kind of translation unit we are processing.
 
  const TranslationUnitKind TUKind;
 
 
 
private:
 
  /// The code-completion handler.
 
  CodeCompletionHandler *CodeComplete = nullptr;
 
 
 
  /// The file that we're performing code-completion for, if any.
 
  const FileEntry *CodeCompletionFile = nullptr;
 
 
 
  /// The offset in file for the code-completion point.
 
  unsigned CodeCompletionOffset = 0;
 
 
 
  /// The location for the code-completion point. This gets instantiated
 
  /// when the CodeCompletionFile gets \#include'ed for preprocessing.
 
  SourceLocation CodeCompletionLoc;
 
 
 
  /// The start location for the file of the code-completion point.
 
  ///
 
  /// This gets instantiated when the CodeCompletionFile gets \#include'ed
 
  /// for preprocessing.
 
  SourceLocation CodeCompletionFileLoc;
 
 
 
  /// The source location of the \c import contextual keyword we just
 
  /// lexed, if any.
 
  SourceLocation ModuleImportLoc;
 
 
 
  /// The import path for named module that we're currently processing.
 
  SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> NamedModuleImportPath;
 
 
 
  /// Whether the import is an `@import` or a standard c++ modules import.
 
  bool IsAtImport = false;
 
 
 
  /// Whether the last token we lexed was an '@'.
 
  bool LastTokenWasAt = false;
 
 
 
  /// A position within a C++20 import-seq.
 
  class StdCXXImportSeq {
 
  public:
 
    enum State : int {
 
      // Positive values represent a number of unclosed brackets.
 
      AtTopLevel = 0,
 
      AfterTopLevelTokenSeq = -1,
 
      AfterExport = -2,
 
      AfterImportSeq = -3,
 
    };
 
 
 
    StdCXXImportSeq(State S) : S(S) {}
 
 
 
    /// Saw any kind of open bracket.
 
    void handleOpenBracket() {
 
      S = static_cast<State>(std::max<int>(S, 0) + 1);
 
    }
 
    /// Saw any kind of close bracket other than '}'.
 
    void handleCloseBracket() {
 
      S = static_cast<State>(std::max<int>(S, 1) - 1);
 
    }
 
    /// Saw a close brace.
 
    void handleCloseBrace() {
 
      handleCloseBracket();
 
      if (S == AtTopLevel && !AfterHeaderName)
 
        S = AfterTopLevelTokenSeq;
 
    }
 
    /// Saw a semicolon.
 
    void handleSemi() {
 
      if (atTopLevel()) {
 
        S = AfterTopLevelTokenSeq;
 
        AfterHeaderName = false;
 
      }
 
    }
 
 
 
    /// Saw an 'export' identifier.
 
    void handleExport() {
 
      if (S == AfterTopLevelTokenSeq)
 
        S = AfterExport;
 
      else if (S <= 0)
 
        S = AtTopLevel;
 
    }
 
    /// Saw an 'import' identifier.
 
    void handleImport() {
 
      if (S == AfterTopLevelTokenSeq || S == AfterExport)
 
        S = AfterImportSeq;
 
      else if (S <= 0)
 
        S = AtTopLevel;
 
    }
 
 
 
    /// Saw a 'header-name' token; do not recognize any more 'import' tokens
 
    /// until we reach a top-level semicolon.
 
    void handleHeaderName() {
 
      if (S == AfterImportSeq)
 
        AfterHeaderName = true;
 
      handleMisc();
 
    }
 
 
 
    /// Saw any other token.
 
    void handleMisc() {
 
      if (S <= 0)
 
        S = AtTopLevel;
 
    }
 
 
 
    bool atTopLevel() { return S <= 0; }
 
    bool afterImportSeq() { return S == AfterImportSeq; }
 
    bool afterTopLevelSeq() { return S == AfterTopLevelTokenSeq; }
 
 
 
  private:
 
    State S;
 
    /// Whether we're in the pp-import-suffix following the header-name in a
 
    /// pp-import. If so, a close-brace is not sufficient to end the
 
    /// top-level-token-seq of an import-seq.
 
    bool AfterHeaderName = false;
 
  };
 
 
 
  /// Our current position within a C++20 import-seq.
 
  StdCXXImportSeq StdCXXImportSeqState = StdCXXImportSeq::AfterTopLevelTokenSeq;
 
 
 
  /// Track whether we are in a Global Module Fragment
 
  class TrackGMF {
 
  public:
 
    enum GMFState : int {
 
      GMFActive = 1,
 
      MaybeGMF = 0,
 
      BeforeGMFIntroducer = -1,
 
      GMFAbsentOrEnded = -2,
 
    };
 
 
 
    TrackGMF(GMFState S) : S(S) {}
 
 
 
    /// Saw a semicolon.
 
    void handleSemi() {
 
      // If it is immediately after the first instance of the module keyword,
 
      // then that introduces the GMF.
 
      if (S == MaybeGMF)
 
        S = GMFActive;
 
    }
 
 
 
    /// Saw an 'export' identifier.
 
    void handleExport() {
 
      // The presence of an 'export' keyword always ends or excludes a GMF.
 
      S = GMFAbsentOrEnded;
 
    }
 
 
 
    /// Saw an 'import' identifier.
 
    void handleImport(bool AfterTopLevelTokenSeq) {
 
      // If we see this before any 'module' kw, then we have no GMF.
 
      if (AfterTopLevelTokenSeq && S == BeforeGMFIntroducer)
 
        S = GMFAbsentOrEnded;
 
    }
 
 
 
    /// Saw a 'module' identifier.
 
    void handleModule(bool AfterTopLevelTokenSeq) {
 
      // This was the first module identifier and not preceded by any token
 
      // that would exclude a GMF.  It could begin a GMF, but only if directly
 
      // followed by a semicolon.
 
      if (AfterTopLevelTokenSeq && S == BeforeGMFIntroducer)
 
        S = MaybeGMF;
 
      else
 
        S = GMFAbsentOrEnded;
 
    }
 
 
 
    /// Saw any other token.
 
    void handleMisc() {
 
      // We saw something other than ; after the 'module' kw, so not a GMF.
 
      if (S == MaybeGMF)
 
        S = GMFAbsentOrEnded;
 
    }
 
 
 
    bool inGMF() { return S == GMFActive; }
 
 
 
  private:
 
    /// Track the transitions into and out of a Global Module Fragment,
 
    /// if one is present.
 
    GMFState S;
 
  };
 
 
 
  TrackGMF TrackGMFState = TrackGMF::BeforeGMFIntroducer;
 
 
 
  /// Track the status of the c++20 module decl.
 
  ///
 
  ///   module-declaration:
 
  ///     'export'[opt] 'module' module-name module-partition[opt]
 
  ///     attribute-specifier-seq[opt] ';'
 
  ///
 
  ///   module-name:
 
  ///     module-name-qualifier[opt] identifier
 
  ///
 
  ///   module-partition:
 
  ///     ':' module-name-qualifier[opt] identifier
 
  ///
 
  ///   module-name-qualifier:
 
  ///     identifier '.'
 
  ///     module-name-qualifier identifier '.'
 
  ///
 
  /// Transition state:
 
  ///
 
  ///   NotAModuleDecl --- export ---> FoundExport
 
  ///   NotAModuleDecl --- module ---> ImplementationCandidate
 
  ///   FoundExport --- module ---> InterfaceCandidate
 
  ///   ImplementationCandidate --- Identifier ---> ImplementationCandidate
 
  ///   ImplementationCandidate --- period ---> ImplementationCandidate
 
  ///   ImplementationCandidate --- colon ---> ImplementationCandidate
 
  ///   InterfaceCandidate --- Identifier ---> InterfaceCandidate
 
  ///   InterfaceCandidate --- period ---> InterfaceCandidate
 
  ///   InterfaceCandidate --- colon ---> InterfaceCandidate
 
  ///   ImplementationCandidate --- Semi ---> NamedModuleImplementation
 
  ///   NamedModuleInterface --- Semi ---> NamedModuleInterface
 
  ///   NamedModuleImplementation --- Anything ---> NamedModuleImplementation
 
  ///   NamedModuleInterface --- Anything ---> NamedModuleInterface
 
  ///
 
  /// FIXME: We haven't handle attribute-specifier-seq here. It may not be bad
 
  /// soon since we don't support any module attributes yet.
 
  class ModuleDeclSeq {
 
    enum ModuleDeclState : int {
 
      NotAModuleDecl,
 
      FoundExport,
 
      InterfaceCandidate,
 
      ImplementationCandidate,
 
      NamedModuleInterface,
 
      NamedModuleImplementation,
 
    };
 
 
 
  public:
 
    ModuleDeclSeq() : State(NotAModuleDecl) {}
 
 
 
    void handleExport() {
 
      if (State == NotAModuleDecl)
 
        State = FoundExport;
 
      else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handleModule() {
 
      if (State == FoundExport)
 
        State = InterfaceCandidate;
 
      else if (State == NotAModuleDecl)
 
        State = ImplementationCandidate;
 
      else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handleIdentifier(IdentifierInfo *Identifier) {
 
      if (isModuleCandidate() && Identifier)
 
        Name += Identifier->getName().str();
 
      else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handleColon() {
 
      if (isModuleCandidate())
 
        Name += ":";
 
      else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handlePeriod() {
 
      if (isModuleCandidate())
 
        Name += ".";
 
      else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handleSemi() {
 
      if (!Name.empty() && isModuleCandidate()) {
 
        if (State == InterfaceCandidate)
 
          State = NamedModuleInterface;
 
        else if (State == ImplementationCandidate)
 
          State = NamedModuleImplementation;
 
        else
 
          llvm_unreachable("Unimaged ModuleDeclState.");
 
      } else if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    void handleMisc() {
 
      if (!isNamedModule())
 
        reset();
 
    }
 
 
 
    bool isModuleCandidate() const {
 
      return State == InterfaceCandidate || State == ImplementationCandidate;
 
    }
 
 
 
    bool isNamedModule() const {
 
      return State == NamedModuleInterface ||
 
             State == NamedModuleImplementation;
 
    }
 
 
 
    bool isNamedInterface() const { return State == NamedModuleInterface; }
 
 
 
    bool isImplementationUnit() const {
 
      return State == NamedModuleImplementation && !getName().contains(':');
 
    }
 
 
 
    StringRef getName() const {
 
      assert(isNamedModule() && "Can't get name from a non named module");
 
      return Name;
 
    }
 
 
 
    StringRef getPrimaryName() const {
 
      assert(isNamedModule() && "Can't get name from a non named module");
 
      return getName().split(':').first;
 
    }
 
 
 
    void reset() {
 
      Name.clear();
 
      State = NotAModuleDecl;
 
    }
 
 
 
  private:
 
    ModuleDeclState State;
 
    std::string Name;
 
  };
 
 
 
  ModuleDeclSeq ModuleDeclState;
 
 
 
  /// Whether the module import expects an identifier next. Otherwise,
 
  /// it expects a '.' or ';'.
 
  bool ModuleImportExpectsIdentifier = false;
 
 
 
  /// The identifier and source location of the currently-active
 
  /// \#pragma clang arc_cf_code_audited begin.
 
  std::pair<IdentifierInfo *, SourceLocation> PragmaARCCFCodeAuditedInfo;
 
 
 
  /// The source location of the currently-active
 
  /// \#pragma clang assume_nonnull begin.
 
  SourceLocation PragmaAssumeNonNullLoc;
 
 
 
  /// Set only for preambles which end with an active
 
  /// \#pragma clang assume_nonnull begin.
 
  ///
 
  /// When the preamble is loaded into the main file,
 
  /// `PragmaAssumeNonNullLoc` will be set to this to
 
  /// replay the unterminated assume_nonnull.
 
  SourceLocation PreambleRecordedPragmaAssumeNonNullLoc;
 
 
 
  /// True if we hit the code-completion point.
 
  bool CodeCompletionReached = false;
 
 
 
  /// The code completion token containing the information
 
  /// on the stem that is to be code completed.
 
  IdentifierInfo *CodeCompletionII = nullptr;
 
 
 
  /// Range for the code completion token.
 
  SourceRange CodeCompletionTokenRange;
 
 
 
  /// The directory that the main file should be considered to occupy,
 
  /// if it does not correspond to a real file (as happens when building a
 
  /// module).
 
  const DirectoryEntry *MainFileDir = nullptr;
 
 
 
  /// The number of bytes that we will initially skip when entering the
 
  /// main file, along with a flag that indicates whether skipping this number
 
  /// of bytes will place the lexer at the start of a line.
 
  ///
 
  /// This is used when loading a precompiled preamble.
 
  std::pair<int, bool> SkipMainFilePreamble;
 
 
 
  /// Whether we hit an error due to reaching max allowed include depth. Allows
 
  /// to avoid hitting the same error over and over again.
 
  bool HasReachedMaxIncludeDepth = false;
 
 
 
  /// The number of currently-active calls to Lex.
 
  ///
 
  /// Lex is reentrant, and asking for an (end-of-phase-4) token can often
 
  /// require asking for multiple additional tokens. This counter makes it
 
  /// possible for Lex to detect whether it's producing a token for the end
 
  /// of phase 4 of translation or for some other situation.
 
  unsigned LexLevel = 0;
 
 
 
  /// The number of (LexLevel 0) preprocessor tokens.
 
  unsigned TokenCount = 0;
 
 
 
  /// Preprocess every token regardless of LexLevel.
 
  bool PreprocessToken = false;
 
 
 
  /// The maximum number of (LexLevel 0) tokens before issuing a -Wmax-tokens
 
  /// warning, or zero for unlimited.
 
  unsigned MaxTokens = 0;
 
  SourceLocation MaxTokensOverrideLoc;
 
 
 
public:
 
  struct PreambleSkipInfo {
 
    SourceLocation HashTokenLoc;
 
    SourceLocation IfTokenLoc;
 
    bool FoundNonSkipPortion;
 
    bool FoundElse;
 
    SourceLocation ElseLoc;
 
 
 
    PreambleSkipInfo(SourceLocation HashTokenLoc, SourceLocation IfTokenLoc,
 
                     bool FoundNonSkipPortion, bool FoundElse,
 
                     SourceLocation ElseLoc)
 
        : HashTokenLoc(HashTokenLoc), IfTokenLoc(IfTokenLoc),
 
          FoundNonSkipPortion(FoundNonSkipPortion), FoundElse(FoundElse),
 
          ElseLoc(ElseLoc) {}
 
  };
 
 
 
  using IncludedFilesSet = llvm::DenseSet<const FileEntry *>;
 
 
 
private:
 
  friend class ASTReader;
 
  friend class MacroArgs;
 
 
 
  class PreambleConditionalStackStore {
 
    enum State {
 
      Off = 0,
 
      Recording = 1,
 
      Replaying = 2,
 
    };
 
 
 
  public:
 
    PreambleConditionalStackStore() = default;
 
 
 
    void startRecording() { ConditionalStackState = Recording; }
 
    void startReplaying() { ConditionalStackState = Replaying; }
 
    bool isRecording() const { return ConditionalStackState == Recording; }
 
    bool isReplaying() const { return ConditionalStackState == Replaying; }
 
 
 
    ArrayRef<PPConditionalInfo> getStack() const {
 
      return ConditionalStack;
 
    }
 
 
 
    void doneReplaying() {
 
      ConditionalStack.clear();
 
      ConditionalStackState = Off;
 
    }
 
 
 
    void setStack(ArrayRef<PPConditionalInfo> s) {
 
      if (!isRecording() && !isReplaying())
 
        return;
 
      ConditionalStack.clear();
 
      ConditionalStack.append(s.begin(), s.end());
 
    }
 
 
 
    bool hasRecordedPreamble() const { return !ConditionalStack.empty(); }
 
 
 
    bool reachedEOFWhileSkipping() const { return SkipInfo.has_value(); }
 
 
 
    void clearSkipInfo() { SkipInfo.reset(); }
 
 
 
    std::optional<PreambleSkipInfo> SkipInfo;
 
 
 
  private:
 
    SmallVector<PPConditionalInfo, 4> ConditionalStack;
 
    State ConditionalStackState = Off;
 
  } PreambleConditionalStack;
 
 
 
  /// The current top of the stack that we're lexing from if
 
  /// not expanding a macro and we are lexing directly from source code.
 
  ///
 
  /// Only one of CurLexer, or CurTokenLexer will be non-null.
 
  std::unique_ptr<Lexer> CurLexer;
 
 
 
  /// The current top of the stack what we're lexing from
 
  /// if not expanding a macro.
 
  ///
 
  /// This is an alias for CurLexer.
 
  PreprocessorLexer *CurPPLexer = nullptr;
 
 
 
  /// Used to find the current FileEntry, if CurLexer is non-null
 
  /// and if applicable.
 
  ///
 
  /// This allows us to implement \#include_next and find directory-specific
 
  /// properties.
 
  ConstSearchDirIterator CurDirLookup = nullptr;
 
 
 
  /// The current macro we are expanding, if we are expanding a macro.
 
  ///
 
  /// One of CurLexer and CurTokenLexer must be null.
 
  std::unique_ptr<TokenLexer> CurTokenLexer;
 
 
 
  /// The kind of lexer we're currently working with.
 
  enum CurLexerKind {
 
    CLK_Lexer,
 
    CLK_TokenLexer,
 
    CLK_CachingLexer,
 
    CLK_DependencyDirectivesLexer,
 
    CLK_LexAfterModuleImport
 
  } CurLexerKind = CLK_Lexer;
 
 
 
  /// If the current lexer is for a submodule that is being built, this
 
  /// is that submodule.
 
  Module *CurLexerSubmodule = nullptr;
 
 
 
  /// Keeps track of the stack of files currently
 
  /// \#included, and macros currently being expanded from, not counting
 
  /// CurLexer/CurTokenLexer.
 
  struct IncludeStackInfo {
 
    enum CurLexerKind           CurLexerKind;
 
    Module                     *TheSubmodule;
 
    std::unique_ptr<Lexer>      TheLexer;
 
    PreprocessorLexer          *ThePPLexer;
 
    std::unique_ptr<TokenLexer> TheTokenLexer;
 
    ConstSearchDirIterator      TheDirLookup;
 
 
 
    // The following constructors are completely useless copies of the default
 
    // versions, only needed to pacify MSVC.
 
    IncludeStackInfo(enum CurLexerKind CurLexerKind, Module *TheSubmodule,
 
                     std::unique_ptr<Lexer> &&TheLexer,
 
                     PreprocessorLexer *ThePPLexer,
 
                     std::unique_ptr<TokenLexer> &&TheTokenLexer,
 
                     ConstSearchDirIterator TheDirLookup)
 
        : CurLexerKind(std::move(CurLexerKind)),
 
          TheSubmodule(std::move(TheSubmodule)), TheLexer(std::move(TheLexer)),
 
          ThePPLexer(std::move(ThePPLexer)),
 
          TheTokenLexer(std::move(TheTokenLexer)),
 
          TheDirLookup(std::move(TheDirLookup)) {}
 
  };
 
  std::vector<IncludeStackInfo> IncludeMacroStack;
 
 
 
  /// Actions invoked when some preprocessor activity is
 
  /// encountered (e.g. a file is \#included, etc).
 
  std::unique_ptr<PPCallbacks> Callbacks;
 
 
 
  struct MacroExpandsInfo {
 
    Token Tok;
 
    MacroDefinition MD;
 
    SourceRange Range;
 
 
 
    MacroExpandsInfo(Token Tok, MacroDefinition MD, SourceRange Range)
 
        : Tok(Tok), MD(MD), Range(Range) {}
 
  };
 
  SmallVector<MacroExpandsInfo, 2> DelayedMacroExpandsCallbacks;
 
 
 
  /// Information about a name that has been used to define a module macro.
 
  struct ModuleMacroInfo {
 
    /// The most recent macro directive for this identifier.
 
    MacroDirective *MD;
 
 
 
    /// The active module macros for this identifier.
 
    llvm::TinyPtrVector<ModuleMacro *> ActiveModuleMacros;
 
 
 
    /// The generation number at which we last updated ActiveModuleMacros.
 
    /// \see Preprocessor::VisibleModules.
 
    unsigned ActiveModuleMacrosGeneration = 0;
 
 
 
    /// Whether this macro name is ambiguous.
 
    bool IsAmbiguous = false;
 
 
 
    /// The module macros that are overridden by this macro.
 
    llvm::TinyPtrVector<ModuleMacro *> OverriddenMacros;
 
 
 
    ModuleMacroInfo(MacroDirective *MD) : MD(MD) {}
 
  };
 
 
 
  /// The state of a macro for an identifier.
 
  class MacroState {
 
    mutable llvm::PointerUnion<MacroDirective *, ModuleMacroInfo *> State;
 
 
 
    ModuleMacroInfo *getModuleInfo(Preprocessor &PP,
 
                                   const IdentifierInfo *II) const {
 
      if (II->isOutOfDate())
 
        PP.updateOutOfDateIdentifier(const_cast<IdentifierInfo&>(*II));
 
      // FIXME: Find a spare bit on IdentifierInfo and store a
 
      //        HasModuleMacros flag.
 
      if (!II->hasMacroDefinition() ||
 
          (!PP.getLangOpts().Modules &&
 
           !PP.getLangOpts().ModulesLocalVisibility) ||
 
          !PP.CurSubmoduleState->VisibleModules.getGeneration())
 
        return nullptr;
 
 
 
      auto *Info = State.dyn_cast<ModuleMacroInfo*>();
 
      if (!Info) {
 
        Info = new (PP.getPreprocessorAllocator())
 
            ModuleMacroInfo(State.get<MacroDirective *>());
 
        State = Info;
 
      }
 
 
 
      if (PP.CurSubmoduleState->VisibleModules.getGeneration() !=
 
          Info->ActiveModuleMacrosGeneration)
 
        PP.updateModuleMacroInfo(II, *Info);
 
      return Info;
 
    }
 
 
 
  public:
 
    MacroState() : MacroState(nullptr) {}
 
    MacroState(MacroDirective *MD) : State(MD) {}
 
 
 
    MacroState(MacroState &&O) noexcept : State(O.State) {
 
      O.State = (MacroDirective *)nullptr;
 
    }
 
 
 
    MacroState &operator=(MacroState &&O) noexcept {
 
      auto S = O.State;
 
      O.State = (MacroDirective *)nullptr;
 
      State = S;
 
      return *this;
 
    }
 
 
 
    ~MacroState() {
 
      if (auto *Info = State.dyn_cast<ModuleMacroInfo*>())
 
        Info->~ModuleMacroInfo();
 
    }
 
 
 
    MacroDirective *getLatest() const {
 
      if (auto *Info = State.dyn_cast<ModuleMacroInfo*>())
 
        return Info->MD;
 
      return State.get<MacroDirective*>();
 
    }
 
 
 
    void setLatest(MacroDirective *MD) {
 
      if (auto *Info = State.dyn_cast<ModuleMacroInfo*>())
 
        Info->MD = MD;
 
      else
 
        State = MD;
 
    }
 
 
 
    bool isAmbiguous(Preprocessor &PP, const IdentifierInfo *II) const {
 
      auto *Info = getModuleInfo(PP, II);
 
      return Info ? Info->IsAmbiguous : false;
 
    }
 
 
 
    ArrayRef<ModuleMacro *>
 
    getActiveModuleMacros(Preprocessor &PP, const IdentifierInfo *II) const {
 
      if (auto *Info = getModuleInfo(PP, II))
 
        return Info->ActiveModuleMacros;
 
      return std::nullopt;
 
    }
 
 
 
    MacroDirective::DefInfo findDirectiveAtLoc(SourceLocation Loc,
 
                                               SourceManager &SourceMgr) const {
 
      // FIXME: Incorporate module macros into the result of this.
 
      if (auto *Latest = getLatest())
 
        return Latest->findDirectiveAtLoc(Loc, SourceMgr);
 
      return {};
 
    }
 
 
 
    void overrideActiveModuleMacros(Preprocessor &PP, IdentifierInfo *II) {
 
      if (auto *Info = getModuleInfo(PP, II)) {
 
        Info->OverriddenMacros.insert(Info->OverriddenMacros.end(),
 
                                      Info->ActiveModuleMacros.begin(),
 
                                      Info->ActiveModuleMacros.end());
 
        Info->ActiveModuleMacros.clear();
 
        Info->IsAmbiguous = false;
 
      }
 
    }
 
 
 
    ArrayRef<ModuleMacro*> getOverriddenMacros() const {
 
      if (auto *Info = State.dyn_cast<ModuleMacroInfo*>())
 
        return Info->OverriddenMacros;
 
      return std::nullopt;
 
    }
 
 
 
    void setOverriddenMacros(Preprocessor &PP,
 
                             ArrayRef<ModuleMacro *> Overrides) {
 
      auto *Info = State.dyn_cast<ModuleMacroInfo*>();
 
      if (!Info) {
 
        if (Overrides.empty())
 
          return;
 
        Info = new (PP.getPreprocessorAllocator())
 
            ModuleMacroInfo(State.get<MacroDirective *>());
 
        State = Info;
 
      }
 
      Info->OverriddenMacros.clear();
 
      Info->OverriddenMacros.insert(Info->OverriddenMacros.end(),
 
                                    Overrides.begin(), Overrides.end());
 
      Info->ActiveModuleMacrosGeneration = 0;
 
    }
 
  };
 
 
 
  /// For each IdentifierInfo that was associated with a macro, we
 
  /// keep a mapping to the history of all macro definitions and #undefs in
 
  /// the reverse order (the latest one is in the head of the list).
 
  ///
 
  /// This mapping lives within the \p CurSubmoduleState.
 
  using MacroMap = llvm::DenseMap<const IdentifierInfo *, MacroState>;
 
 
 
  struct SubmoduleState;
 
 
 
  /// Information about a submodule that we're currently building.
 
  struct BuildingSubmoduleInfo {
 
    /// The module that we are building.
 
    Module *M;
 
 
 
    /// The location at which the module was included.
 
    SourceLocation ImportLoc;
 
 
 
    /// Whether we entered this submodule via a pragma.
 
    bool IsPragma;
 
 
 
    /// The previous SubmoduleState.
 
    SubmoduleState *OuterSubmoduleState;
 
 
 
    /// The number of pending module macro names when we started building this.
 
    unsigned OuterPendingModuleMacroNames;
 
 
 
    BuildingSubmoduleInfo(Module *M, SourceLocation ImportLoc, bool IsPragma,
 
                          SubmoduleState *OuterSubmoduleState,
 
                          unsigned OuterPendingModuleMacroNames)
 
        : M(M), ImportLoc(ImportLoc), IsPragma(IsPragma),
 
          OuterSubmoduleState(OuterSubmoduleState),
 
          OuterPendingModuleMacroNames(OuterPendingModuleMacroNames) {}
 
  };
 
  SmallVector<BuildingSubmoduleInfo, 8> BuildingSubmoduleStack;
 
 
 
  /// Information about a submodule's preprocessor state.
 
  struct SubmoduleState {
 
    /// The macros for the submodule.
 
    MacroMap Macros;
 
 
 
    /// The set of modules that are visible within the submodule.
 
    VisibleModuleSet VisibleModules;
 
 
 
    // FIXME: CounterValue?
 
    // FIXME: PragmaPushMacroInfo?
 
  };
 
  std::map<Module *, SubmoduleState> Submodules;
 
 
 
  /// The preprocessor state for preprocessing outside of any submodule.
 
  SubmoduleState NullSubmoduleState;
 
 
 
  /// The current submodule state. Will be \p NullSubmoduleState if we're not
 
  /// in a submodule.
 
  SubmoduleState *CurSubmoduleState;
 
 
 
  /// The files that have been included.
 
  IncludedFilesSet IncludedFiles;
 
 
 
  /// The set of top-level modules that affected preprocessing, but were not
 
  /// imported.
 
  llvm::SmallSetVector<Module *, 2> AffectingClangModules;
 
 
 
  /// The set of known macros exported from modules.
 
  llvm::FoldingSet<ModuleMacro> ModuleMacros;
 
 
 
  /// The names of potential module macros that we've not yet processed.
 
  llvm::SmallVector<const IdentifierInfo *, 32> PendingModuleMacroNames;
 
 
 
  /// The list of module macros, for each identifier, that are not overridden by
 
  /// any other module macro.
 
  llvm::DenseMap<const IdentifierInfo *, llvm::TinyPtrVector<ModuleMacro *>>
 
      LeafModuleMacros;
 
 
 
  /// Macros that we want to warn because they are not used at the end
 
  /// of the translation unit.
 
  ///
 
  /// We store just their SourceLocations instead of
 
  /// something like MacroInfo*. The benefit of this is that when we are
 
  /// deserializing from PCH, we don't need to deserialize identifier & macros
 
  /// just so that we can report that they are unused, we just warn using
 
  /// the SourceLocations of this set (that will be filled by the ASTReader).
 
  using WarnUnusedMacroLocsTy = llvm::SmallDenseSet<SourceLocation, 32>;
 
  WarnUnusedMacroLocsTy WarnUnusedMacroLocs;
 
 
 
  /// This is a pair of an optional message and source location used for pragmas
 
  /// that annotate macros like pragma clang restrict_expansion and pragma clang
 
  /// deprecated. This pair stores the optional message and the location of the
 
  /// annotation pragma for use producing diagnostics and notes.
 
  using MsgLocationPair = std::pair<std::string, SourceLocation>;
 
 
 
  struct MacroAnnotationInfo {
 
    SourceLocation Location;
 
    std::string Message;
 
  };
 
 
 
  struct MacroAnnotations {
 
    std::optional<MacroAnnotationInfo> DeprecationInfo;
 
    std::optional<MacroAnnotationInfo> RestrictExpansionInfo;
 
    std::optional<SourceLocation> FinalAnnotationLoc;
 
 
 
    static MacroAnnotations makeDeprecation(SourceLocation Loc,
 
                                            std::string Msg) {
 
      return MacroAnnotations{MacroAnnotationInfo{Loc, std::move(Msg)},
 
                              std::nullopt, std::nullopt};
 
    }
 
 
 
    static MacroAnnotations makeRestrictExpansion(SourceLocation Loc,
 
                                                  std::string Msg) {
 
      return MacroAnnotations{
 
          std::nullopt, MacroAnnotationInfo{Loc, std::move(Msg)}, std::nullopt};
 
    }
 
 
 
    static MacroAnnotations makeFinal(SourceLocation Loc) {
 
      return MacroAnnotations{std::nullopt, std::nullopt, Loc};
 
    }
 
  };
 
 
 
  /// Warning information for macro annotations.
 
  llvm::DenseMap<const IdentifierInfo *, MacroAnnotations> AnnotationInfos;
 
 
 
  /// A "freelist" of MacroArg objects that can be
 
  /// reused for quick allocation.
 
  MacroArgs *MacroArgCache = nullptr;
 
 
 
  /// For each IdentifierInfo used in a \#pragma push_macro directive,
 
  /// we keep a MacroInfo stack used to restore the previous macro value.
 
  llvm::DenseMap<IdentifierInfo *, std::vector<MacroInfo *>>
 
      PragmaPushMacroInfo;
 
 
 
  // Various statistics we track for performance analysis.
 
  unsigned NumDirectives = 0;
 
  unsigned NumDefined = 0;
 
  unsigned NumUndefined = 0;
 
  unsigned NumPragma = 0;
 
  unsigned NumIf = 0;
 
  unsigned NumElse = 0;
 
  unsigned NumEndif = 0;
 
  unsigned NumEnteredSourceFiles = 0;
 
  unsigned MaxIncludeStackDepth = 0;
 
  unsigned NumMacroExpanded = 0;
 
  unsigned NumFnMacroExpanded = 0;
 
  unsigned NumBuiltinMacroExpanded = 0;
 
  unsigned NumFastMacroExpanded = 0;
 
  unsigned NumTokenPaste = 0;
 
  unsigned NumFastTokenPaste = 0;
 
  unsigned NumSkipped = 0;
 
 
 
  /// The predefined macros that preprocessor should use from the
 
  /// command line etc.
 
  std::string Predefines;
 
 
 
  /// The file ID for the preprocessor predefines.
 
  FileID PredefinesFileID;
 
 
 
  /// The file ID for the PCH through header.
 
  FileID PCHThroughHeaderFileID;
 
 
 
  /// Whether tokens are being skipped until a #pragma hdrstop is seen.
 
  bool SkippingUntilPragmaHdrStop = false;
 
 
 
  /// Whether tokens are being skipped until the through header is seen.
 
  bool SkippingUntilPCHThroughHeader = false;
 
 
 
  /// \{
 
  /// Cache of macro expanders to reduce malloc traffic.
 
  enum { TokenLexerCacheSize = 8 };
 
  unsigned NumCachedTokenLexers;
 
  std::unique_ptr<TokenLexer> TokenLexerCache[TokenLexerCacheSize];
 
  /// \}
 
 
 
  /// Keeps macro expanded tokens for TokenLexers.
 
  //
 
  /// Works like a stack; a TokenLexer adds the macro expanded tokens that is
 
  /// going to lex in the cache and when it finishes the tokens are removed
 
  /// from the end of the cache.
 
  SmallVector<Token, 16> MacroExpandedTokens;
 
  std::vector<std::pair<TokenLexer *, size_t>> MacroExpandingLexersStack;
 
 
 
  /// A record of the macro definitions and expansions that
 
  /// occurred during preprocessing.
 
  ///
 
  /// This is an optional side structure that can be enabled with
 
  /// \c createPreprocessingRecord() prior to preprocessing.
 
  PreprocessingRecord *Record = nullptr;
 
 
 
  /// Cached tokens state.
 
  using CachedTokensTy = SmallVector<Token, 1>;
 
 
 
  /// Cached tokens are stored here when we do backtracking or
 
  /// lookahead. They are "lexed" by the CachingLex() method.
 
  CachedTokensTy CachedTokens;
 
 
 
  /// The position of the cached token that CachingLex() should
 
  /// "lex" next.
 
  ///
 
  /// If it points beyond the CachedTokens vector, it means that a normal
 
  /// Lex() should be invoked.
 
  CachedTokensTy::size_type CachedLexPos = 0;
 
 
 
  /// Stack of backtrack positions, allowing nested backtracks.
 
  ///
 
  /// The EnableBacktrackAtThisPos() method pushes a position to
 
  /// indicate where CachedLexPos should be set when the BackTrack() method is
 
  /// invoked (at which point the last position is popped).
 
  std::vector<CachedTokensTy::size_type> BacktrackPositions;
 
 
 
  /// True if \p Preprocessor::SkipExcludedConditionalBlock() is running.
 
  /// This is used to guard against calling this function recursively.
 
  ///
 
  /// See comments at the use-site for more context about why it is needed.
 
  bool SkippingExcludedConditionalBlock = false;
 
 
 
  /// Keeps track of skipped range mappings that were recorded while skipping
 
  /// excluded conditional directives. It maps the source buffer pointer at
 
  /// the beginning of a skipped block, to the number of bytes that should be
 
  /// skipped.
 
  llvm::DenseMap<const char *, unsigned> RecordedSkippedRanges;
 
 
 
  void updateOutOfDateIdentifier(IdentifierInfo &II) const;
 
 
 
public:
 
  Preprocessor(std::shared_ptr<PreprocessorOptions> PPOpts,
 
               DiagnosticsEngine &diags, LangOptions &opts, SourceManager &SM,
 
               HeaderSearch &Headers, ModuleLoader &TheModuleLoader,
 
               IdentifierInfoLookup *IILookup = nullptr,
 
               bool OwnsHeaderSearch = false,
 
               TranslationUnitKind TUKind = TU_Complete);
 
 
 
  ~Preprocessor();
 
 
 
  /// Initialize the preprocessor using information about the target.
 
  ///
 
  /// \param Target is owned by the caller and must remain valid for the
 
  /// lifetime of the preprocessor.
 
  /// \param AuxTarget is owned by the caller and must remain valid for
 
  /// the lifetime of the preprocessor.
 
  void Initialize(const TargetInfo &Target,
 
                  const TargetInfo *AuxTarget = nullptr);
 
 
 
  /// Initialize the preprocessor to parse a model file
 
  ///
 
  /// To parse model files the preprocessor of the original source is reused to
 
  /// preserver the identifier table. However to avoid some duplicate
 
  /// information in the preprocessor some cleanup is needed before it is used
 
  /// to parse model files. This method does that cleanup.
 
  void InitializeForModelFile();
 
 
 
  /// Cleanup after model file parsing
 
  void FinalizeForModelFile();
 
 
 
  /// Retrieve the preprocessor options used to initialize this
 
  /// preprocessor.
 
  PreprocessorOptions &getPreprocessorOpts() const { return *PPOpts; }
 
 
 
  DiagnosticsEngine &getDiagnostics() const { return *Diags; }
 
  void setDiagnostics(DiagnosticsEngine &D) { Diags = &D; }
 
 
 
  const LangOptions &getLangOpts() const { return LangOpts; }
 
  const TargetInfo &getTargetInfo() const { return *Target; }
 
  const TargetInfo *getAuxTargetInfo() const { return AuxTarget; }
 
  FileManager &getFileManager() const { return FileMgr; }
 
  SourceManager &getSourceManager() const { return SourceMgr; }
 
  HeaderSearch &getHeaderSearchInfo() const { return HeaderInfo; }
 
 
 
  IdentifierTable &getIdentifierTable() { return Identifiers; }
 
  const IdentifierTable &getIdentifierTable() const { return Identifiers; }
 
  SelectorTable &getSelectorTable() { return Selectors; }
 
  Builtin::Context &getBuiltinInfo() { return *BuiltinInfo; }
 
  llvm::BumpPtrAllocator &getPreprocessorAllocator() { return BP; }
 
 
 
  void setExternalSource(ExternalPreprocessorSource *Source) {
 
    ExternalSource = Source;
 
  }
 
 
 
  ExternalPreprocessorSource *getExternalSource() const {
 
    return ExternalSource;
 
  }
 
 
 
  /// Retrieve the module loader associated with this preprocessor.
 
  ModuleLoader &getModuleLoader() const { return TheModuleLoader; }
 
 
 
  bool hadModuleLoaderFatalFailure() const {
 
    return TheModuleLoader.HadFatalFailure;
 
  }
 
 
 
  /// Retrieve the number of Directives that have been processed by the
 
  /// Preprocessor.
 
  unsigned getNumDirectives() const {
 
    return NumDirectives;
 
  }
 
 
 
  /// True if we are currently preprocessing a #if or #elif directive
 
  bool isParsingIfOrElifDirective() const {
 
    return ParsingIfOrElifDirective;
 
  }
 
 
 
  /// Control whether the preprocessor retains comments in output.
 
  void SetCommentRetentionState(bool KeepComments, bool KeepMacroComments) {
 
    this->KeepComments = KeepComments | KeepMacroComments;
 
    this->KeepMacroComments = KeepMacroComments;
 
  }
 
 
 
  bool getCommentRetentionState() const { return KeepComments; }
 
 
 
  void setPragmasEnabled(bool Enabled) { PragmasEnabled = Enabled; }
 
  bool getPragmasEnabled() const { return PragmasEnabled; }
 
 
 
  void SetSuppressIncludeNotFoundError(bool Suppress) {
 
    SuppressIncludeNotFoundError = Suppress;
 
  }
 
 
 
  bool GetSuppressIncludeNotFoundError() {
 
    return SuppressIncludeNotFoundError;
 
  }
 
 
 
  /// Sets whether the preprocessor is responsible for producing output or if
 
  /// it is producing tokens to be consumed by Parse and Sema.
 
  void setPreprocessedOutput(bool IsPreprocessedOutput) {
 
    PreprocessedOutput = IsPreprocessedOutput;
 
  }
 
 
 
  /// Returns true if the preprocessor is responsible for generating output,
 
  /// false if it is producing tokens to be consumed by Parse and Sema.
 
  bool isPreprocessedOutput() const { return PreprocessedOutput; }
 
 
 
  /// Return true if we are lexing directly from the specified lexer.
 
  bool isCurrentLexer(const PreprocessorLexer *L) const {
 
    return CurPPLexer == L;
 
  }
 
 
 
  /// Return the current lexer being lexed from.
 
  ///
 
  /// Note that this ignores any potentially active macro expansions and _Pragma
 
  /// expansions going on at the time.
 
  PreprocessorLexer *getCurrentLexer() const { return CurPPLexer; }
 
 
 
  /// Return the current file lexer being lexed from.
 
  ///
 
  /// Note that this ignores any potentially active macro expansions and _Pragma
 
  /// expansions going on at the time.
 
  PreprocessorLexer *getCurrentFileLexer() const;
 
 
 
  /// Return the submodule owning the file being lexed. This may not be
 
  /// the current module if we have changed modules since entering the file.
 
  Module *getCurrentLexerSubmodule() const { return CurLexerSubmodule; }
 
 
 
  /// Returns the FileID for the preprocessor predefines.
 
  FileID getPredefinesFileID() const { return PredefinesFileID; }
 
 
 
  /// \{
 
  /// Accessors for preprocessor callbacks.
 
  ///
 
  /// Note that this class takes ownership of any PPCallbacks object given to
 
  /// it.
 
  PPCallbacks *getPPCallbacks() const { return Callbacks.get(); }
 
  void addPPCallbacks(std::unique_ptr<PPCallbacks> C) {
 
    if (Callbacks)
 
      C = std::make_unique<PPChainedCallbacks>(std::move(C),
 
                                                std::move(Callbacks));
 
    Callbacks = std::move(C);
 
  }
 
  /// \}
 
 
 
  /// Get the number of tokens processed so far.
 
  unsigned getTokenCount() const { return TokenCount; }
 
 
 
  /// Get the max number of tokens before issuing a -Wmax-tokens warning.
 
  unsigned getMaxTokens() const { return MaxTokens; }
 
 
 
  void overrideMaxTokens(unsigned Value, SourceLocation Loc) {
 
    MaxTokens = Value;
 
    MaxTokensOverrideLoc = Loc;
 
  };
 
 
 
  SourceLocation getMaxTokensOverrideLoc() const { return MaxTokensOverrideLoc; }
 
 
 
  /// Register a function that would be called on each token in the final
 
  /// expanded token stream.
 
  /// This also reports annotation tokens produced by the parser.
 
  void setTokenWatcher(llvm::unique_function<void(const clang::Token &)> F) {
 
    OnToken = std::move(F);
 
  }
 
 
 
  void setPreprocessToken(bool Preprocess) { PreprocessToken = Preprocess; }
 
 
 
  bool isMacroDefined(StringRef Id) {
 
    return isMacroDefined(&Identifiers.get(Id));
 
  }
 
  bool isMacroDefined(const IdentifierInfo *II) {
 
    return II->hasMacroDefinition() &&
 
           (!getLangOpts().Modules || (bool)getMacroDefinition(II));
 
  }
 
 
 
  /// Determine whether II is defined as a macro within the module M,
 
  /// if that is a module that we've already preprocessed. Does not check for
 
  /// macros imported into M.
 
  bool isMacroDefinedInLocalModule(const IdentifierInfo *II, Module *M) {
 
    if (!II->hasMacroDefinition())
 
      return false;
 
    auto I = Submodules.find(M);
 
    if (I == Submodules.end())
 
      return false;
 
    auto J = I->second.Macros.find(II);
 
    if (J == I->second.Macros.end())
 
      return false;
 
    auto *MD = J->second.getLatest();
 
    return MD && MD->isDefined();
 
  }
 
 
 
  MacroDefinition getMacroDefinition(const IdentifierInfo *II) {
 
    if (!II->hasMacroDefinition())
 
      return {};
 
 
 
    MacroState &S = CurSubmoduleState->Macros[II];
 
    auto *MD = S.getLatest();
 
    while (MD && isa<VisibilityMacroDirective>(MD))
 
      MD = MD->getPrevious();
 
    return MacroDefinition(dyn_cast_or_null<DefMacroDirective>(MD),
 
                           S.getActiveModuleMacros(*this, II),
 
                           S.isAmbiguous(*this, II));
 
  }
 
 
 
  MacroDefinition getMacroDefinitionAtLoc(const IdentifierInfo *II,
 
                                          SourceLocation Loc) {
 
    if (!II->hadMacroDefinition())
 
      return {};
 
 
 
    MacroState &S = CurSubmoduleState->Macros[II];
 
    MacroDirective::DefInfo DI;
 
    if (auto *MD = S.getLatest())
 
      DI = MD->findDirectiveAtLoc(Loc, getSourceManager());
 
    // FIXME: Compute the set of active module macros at the specified location.
 
    return MacroDefinition(DI.getDirective(),
 
                           S.getActiveModuleMacros(*this, II),
 
                           S.isAmbiguous(*this, II));
 
  }
 
 
 
  /// Given an identifier, return its latest non-imported MacroDirective
 
  /// if it is \#define'd and not \#undef'd, or null if it isn't \#define'd.
 
  MacroDirective *getLocalMacroDirective(const IdentifierInfo *II) const {
 
    if (!II->hasMacroDefinition())
 
      return nullptr;
 
 
 
    auto *MD = getLocalMacroDirectiveHistory(II);
 
    if (!MD || MD->getDefinition().isUndefined())
 
      return nullptr;
 
 
 
    return MD;
 
  }
 
 
 
  const MacroInfo *getMacroInfo(const IdentifierInfo *II) const {
 
    return const_cast<Preprocessor*>(this)->getMacroInfo(II);
 
  }
 
 
 
  MacroInfo *getMacroInfo(const IdentifierInfo *II) {
 
    if (!II->hasMacroDefinition())
 
      return nullptr;
 
    if (auto MD = getMacroDefinition(II))
 
      return MD.getMacroInfo();
 
    return nullptr;
 
  }
 
 
 
  /// Given an identifier, return the latest non-imported macro
 
  /// directive for that identifier.
 
  ///
 
  /// One can iterate over all previous macro directives from the most recent
 
  /// one.
 
  MacroDirective *getLocalMacroDirectiveHistory(const IdentifierInfo *II) const;
 
 
 
  /// Add a directive to the macro directive history for this identifier.
 
  void appendMacroDirective(IdentifierInfo *II, MacroDirective *MD);
 
  DefMacroDirective *appendDefMacroDirective(IdentifierInfo *II, MacroInfo *MI,
 
                                             SourceLocation Loc) {
 
    DefMacroDirective *MD = AllocateDefMacroDirective(MI, Loc);
 
    appendMacroDirective(II, MD);
 
    return MD;
 
  }
 
  DefMacroDirective *appendDefMacroDirective(IdentifierInfo *II,
 
                                             MacroInfo *MI) {
 
    return appendDefMacroDirective(II, MI, MI->getDefinitionLoc());
 
  }
 
 
 
  /// Set a MacroDirective that was loaded from a PCH file.
 
  void setLoadedMacroDirective(IdentifierInfo *II, MacroDirective *ED,
 
                               MacroDirective *MD);
 
 
 
  /// Register an exported macro for a module and identifier.
 
  ModuleMacro *addModuleMacro(Module *Mod, IdentifierInfo *II, MacroInfo *Macro,
 
                              ArrayRef<ModuleMacro *> Overrides, bool &IsNew);
 
  ModuleMacro *getModuleMacro(Module *Mod, const IdentifierInfo *II);
 
 
 
  /// Get the list of leaf (non-overridden) module macros for a name.
 
  ArrayRef<ModuleMacro*> getLeafModuleMacros(const IdentifierInfo *II) const {
 
    if (II->isOutOfDate())
 
      updateOutOfDateIdentifier(const_cast<IdentifierInfo&>(*II));
 
    auto I = LeafModuleMacros.find(II);
 
    if (I != LeafModuleMacros.end())
 
      return I->second;
 
    return std::nullopt;
 
  }
 
 
 
  /// Get the list of submodules that we're currently building.
 
  ArrayRef<BuildingSubmoduleInfo> getBuildingSubmodules() const {
 
    return BuildingSubmoduleStack;
 
  }
 
 
 
  /// \{
 
  /// Iterators for the macro history table. Currently defined macros have
 
  /// IdentifierInfo::hasMacroDefinition() set and an empty
 
  /// MacroInfo::getUndefLoc() at the head of the list.
 
  using macro_iterator = MacroMap::const_iterator;
 
 
 
  macro_iterator macro_begin(bool IncludeExternalMacros = true) const;
 
  macro_iterator macro_end(bool IncludeExternalMacros = true) const;
 
 
 
  llvm::iterator_range<macro_iterator>
 
  macros(bool IncludeExternalMacros = true) const {
 
    macro_iterator begin = macro_begin(IncludeExternalMacros);
 
    macro_iterator end = macro_end(IncludeExternalMacros);
 
    return llvm::make_range(begin, end);
 
  }
 
 
 
  /// \}
 
 
 
  /// Mark the given clang module as affecting the current clang module or translation unit.
 
  void markClangModuleAsAffecting(Module *M) {
 
    assert(M->isModuleMapModule());
 
    if (!BuildingSubmoduleStack.empty()) {
 
      if (M != BuildingSubmoduleStack.back().M)
 
        BuildingSubmoduleStack.back().M->AffectingClangModules.insert(M);
 
    } else {
 
      AffectingClangModules.insert(M);
 
    }
 
  }
 
 
 
  /// Get the set of top-level clang modules that affected preprocessing, but were not
 
  /// imported.
 
  const llvm::SmallSetVector<Module *, 2> &getAffectingClangModules() const {
 
    return AffectingClangModules;
 
  }
 
 
 
  /// Mark the file as included.
 
  /// Returns true if this is the first time the file was included.
 
  bool markIncluded(const FileEntry *File) {
 
    HeaderInfo.getFileInfo(File);
 
    return IncludedFiles.insert(File).second;
 
  }
 
 
 
  /// Return true if this header has already been included.
 
  bool alreadyIncluded(const FileEntry *File) const {
 
    return IncludedFiles.count(File);
 
  }
 
 
 
  /// Get the set of included files.
 
  IncludedFilesSet &getIncludedFiles() { return IncludedFiles; }
 
  const IncludedFilesSet &getIncludedFiles() const { return IncludedFiles; }
 
 
 
  /// Return the name of the macro defined before \p Loc that has
 
  /// spelling \p Tokens.  If there are multiple macros with same spelling,
 
  /// return the last one defined.
 
  StringRef getLastMacroWithSpelling(SourceLocation Loc,
 
                                     ArrayRef<TokenValue> Tokens) const;
 
 
 
  /// Get the predefines for this processor.
 
  /// Used by some third-party tools to inspect and add predefines (see
 
  /// https://github.com/llvm/llvm-project/issues/57483).
 
  const std::string &getPredefines() const { return Predefines; }
 
 
 
  /// Set the predefines for this Preprocessor.
 
  ///
 
  /// These predefines are automatically injected when parsing the main file.
 
  void setPredefines(std::string P) { Predefines = std::move(P); }
 
 
 
  /// Return information about the specified preprocessor
 
  /// identifier token.
 
  IdentifierInfo *getIdentifierInfo(StringRef Name) const {
 
    return &Identifiers.get(Name);
 
  }
 
 
 
  /// Add the specified pragma handler to this preprocessor.
 
  ///
 
  /// If \p Namespace is non-null, then it is a token required to exist on the
 
  /// pragma line before the pragma string starts, e.g. "STDC" or "GCC".
 
  void AddPragmaHandler(StringRef Namespace, PragmaHandler *Handler);
 
  void AddPragmaHandler(PragmaHandler *Handler) {
 
    AddPragmaHandler(StringRef(), Handler);
 
  }
 
 
 
  /// Remove the specific pragma handler from this preprocessor.
 
  ///
 
  /// If \p Namespace is non-null, then it should be the namespace that
 
  /// \p Handler was added to. It is an error to remove a handler that
 
  /// has not been registered.
 
  void RemovePragmaHandler(StringRef Namespace, PragmaHandler *Handler);
 
  void RemovePragmaHandler(PragmaHandler *Handler) {
 
    RemovePragmaHandler(StringRef(), Handler);
 
  }
 
 
 
  /// Install empty handlers for all pragmas (making them ignored).
 
  void IgnorePragmas();
 
 
 
  /// Set empty line handler.
 
  void setEmptylineHandler(EmptylineHandler *Handler) { Emptyline = Handler; }
 
 
 
  EmptylineHandler *getEmptylineHandler() const { return Emptyline; }
 
 
 
  /// Add the specified comment handler to the preprocessor.
 
  void addCommentHandler(CommentHandler *Handler);
 
 
 
  /// Remove the specified comment handler.
 
  ///
 
  /// It is an error to remove a handler that has not been registered.
 
  void removeCommentHandler(CommentHandler *Handler);
 
 
 
  /// Set the code completion handler to the given object.
 
  void setCodeCompletionHandler(CodeCompletionHandler &Handler) {
 
    CodeComplete = &Handler;
 
  }
 
 
 
  /// Retrieve the current code-completion handler.
 
  CodeCompletionHandler *getCodeCompletionHandler() const {
 
    return CodeComplete;
 
  }
 
 
 
  /// Clear out the code completion handler.
 
  void clearCodeCompletionHandler() {
 
    CodeComplete = nullptr;
 
  }
 
 
 
  /// Hook used by the lexer to invoke the "included file" code
 
  /// completion point.
 
  void CodeCompleteIncludedFile(llvm::StringRef Dir, bool IsAngled);
 
 
 
  /// Hook used by the lexer to invoke the "natural language" code
 
  /// completion point.
 
  void CodeCompleteNaturalLanguage();
 
 
 
  /// Set the code completion token for filtering purposes.
 
  void setCodeCompletionIdentifierInfo(IdentifierInfo *Filter) {
 
    CodeCompletionII = Filter;
 
  }
 
 
 
  /// Set the code completion token range for detecting replacement range later
 
  /// on.
 
  void setCodeCompletionTokenRange(const SourceLocation Start,
 
                                   const SourceLocation End) {
 
    CodeCompletionTokenRange = {Start, End};
 
  }
 
  SourceRange getCodeCompletionTokenRange() const {
 
    return CodeCompletionTokenRange;
 
  }
 
 
 
  /// Get the code completion token for filtering purposes.
 
  StringRef getCodeCompletionFilter() {
 
    if (CodeCompletionII)
 
      return CodeCompletionII->getName();
 
    return {};
 
  }
 
 
 
  /// Retrieve the preprocessing record, or NULL if there is no
 
  /// preprocessing record.
 
  PreprocessingRecord *getPreprocessingRecord() const { return Record; }
 
 
 
  /// Create a new preprocessing record, which will keep track of
 
  /// all macro expansions, macro definitions, etc.
 
  void createPreprocessingRecord();
 
 
 
  /// Returns true if the FileEntry is the PCH through header.
 
  bool isPCHThroughHeader(const FileEntry *FE);
 
 
 
  /// True if creating a PCH with a through header.
 
  bool creatingPCHWithThroughHeader();
 
 
 
  /// True if using a PCH with a through header.
 
  bool usingPCHWithThroughHeader();
 
 
 
  /// True if creating a PCH with a #pragma hdrstop.
 
  bool creatingPCHWithPragmaHdrStop();
 
 
 
  /// True if using a PCH with a #pragma hdrstop.
 
  bool usingPCHWithPragmaHdrStop();
 
 
 
  /// Skip tokens until after the #include of the through header or
 
  /// until after a #pragma hdrstop.
 
  void SkipTokensWhileUsingPCH();
 
 
 
  /// Process directives while skipping until the through header or
 
  /// #pragma hdrstop is found.
 
  void HandleSkippedDirectiveWhileUsingPCH(Token &Result,
 
                                           SourceLocation HashLoc);
 
 
 
  /// Enter the specified FileID as the main source file,
 
  /// which implicitly adds the builtin defines etc.
 
  void EnterMainSourceFile();
 
 
 
  /// Inform the preprocessor callbacks that processing is complete.
 
  void EndSourceFile();
 
 
 
  /// Add a source file to the top of the include stack and
 
  /// start lexing tokens from it instead of the current buffer.
 
  ///
 
  /// Emits a diagnostic, doesn't enter the file, and returns true on error.
 
  bool EnterSourceFile(FileID FID, ConstSearchDirIterator Dir,
 
                       SourceLocation Loc, bool IsFirstIncludeOfFile = true);
 
 
 
  /// Add a Macro to the top of the include stack and start lexing
 
  /// tokens from it instead of the current buffer.
 
  ///
 
  /// \param Args specifies the tokens input to a function-like macro.
 
  /// \param ILEnd specifies the location of the ')' for a function-like macro
 
  /// or the identifier for an object-like macro.
 
  void EnterMacro(Token &Tok, SourceLocation ILEnd, MacroInfo *Macro,
 
                  MacroArgs *Args);
 
 
 
private:
 
  /// Add a "macro" context to the top of the include stack,
 
  /// which will cause the lexer to start returning the specified tokens.
 
  ///
 
  /// If \p DisableMacroExpansion is true, tokens lexed from the token stream
 
  /// will not be subject to further macro expansion. Otherwise, these tokens
 
  /// will be re-macro-expanded when/if expansion is enabled.
 
  ///
 
  /// If \p OwnsTokens is false, this method assumes that the specified stream
 
  /// of tokens has a permanent owner somewhere, so they do not need to be
 
  /// copied. If it is true, it assumes the array of tokens is allocated with
 
  /// \c new[] and the Preprocessor will delete[] it.
 
  ///
 
  /// If \p IsReinject the resulting tokens will have Token::IsReinjected flag
 
  /// set, see the flag documentation for details.
 
  void EnterTokenStream(const Token *Toks, unsigned NumToks,
 
                        bool DisableMacroExpansion, bool OwnsTokens,
 
                        bool IsReinject);
 
 
 
public:
 
  void EnterTokenStream(std::unique_ptr<Token[]> Toks, unsigned NumToks,
 
                        bool DisableMacroExpansion, bool IsReinject) {
 
    EnterTokenStream(Toks.release(), NumToks, DisableMacroExpansion, true,
 
                     IsReinject);
 
  }
 
 
 
  void EnterTokenStream(ArrayRef<Token> Toks, bool DisableMacroExpansion,
 
                        bool IsReinject) {
 
    EnterTokenStream(Toks.data(), Toks.size(), DisableMacroExpansion, false,
 
                     IsReinject);
 
  }
 
 
 
  /// Pop the current lexer/macro exp off the top of the lexer stack.
 
  ///
 
  /// This should only be used in situations where the current state of the
 
  /// top-of-stack lexer is known.
 
  void RemoveTopOfLexerStack();
 
 
 
  /// From the point that this method is called, and until
 
  /// CommitBacktrackedTokens() or Backtrack() is called, the Preprocessor
 
  /// keeps track of the lexed tokens so that a subsequent Backtrack() call will
 
  /// make the Preprocessor re-lex the same tokens.
 
  ///
 
  /// Nested backtracks are allowed, meaning that EnableBacktrackAtThisPos can
 
  /// be called multiple times and CommitBacktrackedTokens/Backtrack calls will
 
  /// be combined with the EnableBacktrackAtThisPos calls in reverse order.
 
  ///
 
  /// NOTE: *DO NOT* forget to call either CommitBacktrackedTokens or Backtrack
 
  /// at some point after EnableBacktrackAtThisPos. If you don't, caching of
 
  /// tokens will continue indefinitely.
 
  ///
 
  void EnableBacktrackAtThisPos();
 
 
 
  /// Disable the last EnableBacktrackAtThisPos call.
 
  void CommitBacktrackedTokens();
 
 
 
  /// Make Preprocessor re-lex the tokens that were lexed since
 
  /// EnableBacktrackAtThisPos() was previously called.
 
  void Backtrack();
 
 
 
  /// True if EnableBacktrackAtThisPos() was called and
 
  /// caching of tokens is on.
 
  bool isBacktrackEnabled() const { return !BacktrackPositions.empty(); }
 
 
 
  /// Lex the next token for this preprocessor.
 
  void Lex(Token &Result);
 
 
 
  /// Lex a token, forming a header-name token if possible.
 
  bool LexHeaderName(Token &Result, bool AllowMacroExpansion = true);
 
 
 
  bool LexAfterModuleImport(Token &Result);
 
  void CollectPpImportSuffix(SmallVectorImpl<Token> &Toks);
 
 
 
  void makeModuleVisible(Module *M, SourceLocation Loc);
 
 
 
  SourceLocation getModuleImportLoc(Module *M) const {
 
    return CurSubmoduleState->VisibleModules.getImportLoc(M);
 
  }
 
 
 
  /// Lex a string literal, which may be the concatenation of multiple
 
  /// string literals and may even come from macro expansion.
 
  /// \returns true on success, false if a error diagnostic has been generated.
 
  bool LexStringLiteral(Token &Result, std::string &String,
 
                        const char *DiagnosticTag, bool AllowMacroExpansion) {
 
    if (AllowMacroExpansion)
 
      Lex(Result);
 
    else
 
      LexUnexpandedToken(Result);
 
    return FinishLexStringLiteral(Result, String, DiagnosticTag,
 
                                  AllowMacroExpansion);
 
  }
 
 
 
  /// Complete the lexing of a string literal where the first token has
 
  /// already been lexed (see LexStringLiteral).
 
  bool FinishLexStringLiteral(Token &Result, std::string &String,
 
                              const char *DiagnosticTag,
 
                              bool AllowMacroExpansion);
 
 
 
  /// Lex a token.  If it's a comment, keep lexing until we get
 
  /// something not a comment.
 
  ///
 
  /// This is useful in -E -C mode where comments would foul up preprocessor
 
  /// directive handling.
 
  void LexNonComment(Token &Result) {
 
    do
 
      Lex(Result);
 
    while (Result.getKind() == tok::comment);
 
  }
 
 
 
  /// Just like Lex, but disables macro expansion of identifier tokens.
 
  void LexUnexpandedToken(Token &Result) {
 
    // Disable macro expansion.
 
    bool OldVal = DisableMacroExpansion;
 
    DisableMacroExpansion = true;
 
    // Lex the token.
 
    Lex(Result);
 
 
 
    // Reenable it.
 
    DisableMacroExpansion = OldVal;
 
  }
 
 
 
  /// Like LexNonComment, but this disables macro expansion of
 
  /// identifier tokens.
 
  void LexUnexpandedNonComment(Token &Result) {
 
    do
 
      LexUnexpandedToken(Result);
 
    while (Result.getKind() == tok::comment);
 
  }
 
 
 
  /// Parses a simple integer literal to get its numeric value.  Floating
 
  /// point literals and user defined literals are rejected.  Used primarily to
 
  /// handle pragmas that accept integer arguments.
 
  bool parseSimpleIntegerLiteral(Token &Tok, uint64_t &Value);
 
 
 
  /// Disables macro expansion everywhere except for preprocessor directives.
 
  void SetMacroExpansionOnlyInDirectives() {
 
    DisableMacroExpansion = true;
 
    MacroExpansionInDirectivesOverride = true;
 
  }
 
 
 
  /// Peeks ahead N tokens and returns that token without consuming any
 
  /// tokens.
 
  ///
 
  /// LookAhead(0) returns the next token that would be returned by Lex(),
 
  /// LookAhead(1) returns the token after it, etc.  This returns normal
 
  /// tokens after phase 5.  As such, it is equivalent to using
 
  /// 'Lex', not 'LexUnexpandedToken'.
 
  const Token &LookAhead(unsigned N) {
 
    assert(LexLevel == 0 && "cannot use lookahead while lexing");
 
    if (CachedLexPos + N < CachedTokens.size())
 
      return CachedTokens[CachedLexPos+N];
 
    else
 
      return PeekAhead(N+1);
 
  }
 
 
 
  /// When backtracking is enabled and tokens are cached,
 
  /// this allows to revert a specific number of tokens.
 
  ///
 
  /// Note that the number of tokens being reverted should be up to the last
 
  /// backtrack position, not more.
 
  void RevertCachedTokens(unsigned N) {
 
    assert(isBacktrackEnabled() &&
 
           "Should only be called when tokens are cached for backtracking");
 
    assert(signed(CachedLexPos) - signed(N) >= signed(BacktrackPositions.back())
 
         && "Should revert tokens up to the last backtrack position, not more");
 
    assert(signed(CachedLexPos) - signed(N) >= 0 &&
 
           "Corrupted backtrack positions ?");
 
    CachedLexPos -= N;
 
  }
 
 
 
  /// Enters a token in the token stream to be lexed next.
 
  ///
 
  /// If BackTrack() is called afterwards, the token will remain at the
 
  /// insertion point.
 
  /// If \p IsReinject is true, resulting token will have Token::IsReinjected
 
  /// flag set. See the flag documentation for details.
 
  void EnterToken(const Token &Tok, bool IsReinject) {
 
    if (LexLevel) {
 
      // It's not correct in general to enter caching lex mode while in the
 
      // middle of a nested lexing action.
 
      auto TokCopy = std::make_unique<Token[]>(1);
 
      TokCopy[0] = Tok;
 
      EnterTokenStream(std::move(TokCopy), 1, true, IsReinject);
 
    } else {
 
      EnterCachingLexMode();
 
      assert(IsReinject && "new tokens in the middle of cached stream");
 
      CachedTokens.insert(CachedTokens.begin()+CachedLexPos, Tok);
 
    }
 
  }
 
 
 
  /// We notify the Preprocessor that if it is caching tokens (because
 
  /// backtrack is enabled) it should replace the most recent cached tokens
 
  /// with the given annotation token. This function has no effect if
 
  /// backtracking is not enabled.
 
  ///
 
  /// Note that the use of this function is just for optimization, so that the
 
  /// cached tokens doesn't get re-parsed and re-resolved after a backtrack is
 
  /// invoked.
 
  void AnnotateCachedTokens(const Token &Tok) {
 
    assert(Tok.isAnnotation() && "Expected annotation token");
 
    if (CachedLexPos != 0 && isBacktrackEnabled())
 
      AnnotatePreviousCachedTokens(Tok);
 
  }
 
 
 
  /// Get the location of the last cached token, suitable for setting the end
 
  /// location of an annotation token.
 
  SourceLocation getLastCachedTokenLocation() const {
 
    assert(CachedLexPos != 0);
 
    return CachedTokens[CachedLexPos-1].getLastLoc();
 
  }
 
 
 
  /// Whether \p Tok is the most recent token (`CachedLexPos - 1`) in
 
  /// CachedTokens.
 
  bool IsPreviousCachedToken(const Token &Tok) const;
 
 
 
  /// Replace token in `CachedLexPos - 1` in CachedTokens by the tokens
 
  /// in \p NewToks.
 
  ///
 
  /// Useful when a token needs to be split in smaller ones and CachedTokens
 
  /// most recent token must to be updated to reflect that.
 
  void ReplacePreviousCachedToken(ArrayRef<Token> NewToks);
 
 
 
  /// Replace the last token with an annotation token.
 
  ///
 
  /// Like AnnotateCachedTokens(), this routine replaces an
 
  /// already-parsed (and resolved) token with an annotation
 
  /// token. However, this routine only replaces the last token with
 
  /// the annotation token; it does not affect any other cached
 
  /// tokens. This function has no effect if backtracking is not
 
  /// enabled.
 
  void ReplaceLastTokenWithAnnotation(const Token &Tok) {
 
    assert(Tok.isAnnotation() && "Expected annotation token");
 
    if (CachedLexPos != 0 && isBacktrackEnabled())
 
      CachedTokens[CachedLexPos-1] = Tok;
 
  }
 
 
 
  /// Enter an annotation token into the token stream.
 
  void EnterAnnotationToken(SourceRange Range, tok::TokenKind Kind,
 
                            void *AnnotationVal);
 
 
 
  /// Determine whether it's possible for a future call to Lex to produce an
 
  /// annotation token created by a previous call to EnterAnnotationToken.
 
  bool mightHavePendingAnnotationTokens() {
 
    return CurLexerKind != CLK_Lexer;
 
  }
 
 
 
  /// Update the current token to represent the provided
 
  /// identifier, in order to cache an action performed by typo correction.
 
  void TypoCorrectToken(const Token &Tok) {
 
    assert(Tok.getIdentifierInfo() && "Expected identifier token");
 
    if (CachedLexPos != 0 && isBacktrackEnabled())
 
      CachedTokens[CachedLexPos-1] = Tok;
 
  }
 
 
 
  /// Recompute the current lexer kind based on the CurLexer/
 
  /// CurTokenLexer pointers.
 
  void recomputeCurLexerKind();
 
 
 
  /// Returns true if incremental processing is enabled
 
  bool isIncrementalProcessingEnabled() const {
 
    return getLangOpts().IncrementalExtensions;
 
  }
 
 
 
  /// Enables the incremental processing
 
  void enableIncrementalProcessing(bool value = true) {
 
    // FIXME: Drop this interface.
 
    const_cast<LangOptions &>(getLangOpts()).IncrementalExtensions = value;
 
  }
 
 
 
  /// Specify the point at which code-completion will be performed.
 
  ///
 
  /// \param File the file in which code completion should occur. If
 
  /// this file is included multiple times, code-completion will
 
  /// perform completion the first time it is included. If NULL, this
 
  /// function clears out the code-completion point.
 
  ///
 
  /// \param Line the line at which code completion should occur
 
  /// (1-based).
 
  ///
 
  /// \param Column the column at which code completion should occur
 
  /// (1-based).
 
  ///
 
  /// \returns true if an error occurred, false otherwise.
 
  bool SetCodeCompletionPoint(const FileEntry *File,
 
                              unsigned Line, unsigned Column);
 
 
 
  /// Determine if we are performing code completion.
 
  bool isCodeCompletionEnabled() const { return CodeCompletionFile != nullptr; }
 
 
 
  /// Returns the location of the code-completion point.
 
  ///
 
  /// Returns an invalid location if code-completion is not enabled or the file
 
  /// containing the code-completion point has not been lexed yet.
 
  SourceLocation getCodeCompletionLoc() const { return CodeCompletionLoc; }
 
 
 
  /// Returns the start location of the file of code-completion point.
 
  ///
 
  /// Returns an invalid location if code-completion is not enabled or the file
 
  /// containing the code-completion point has not been lexed yet.
 
  SourceLocation getCodeCompletionFileLoc() const {
 
    return CodeCompletionFileLoc;
 
  }
 
 
 
  /// Returns true if code-completion is enabled and we have hit the
 
  /// code-completion point.
 
  bool isCodeCompletionReached() const { return CodeCompletionReached; }
 
 
 
  /// Note that we hit the code-completion point.
 
  void setCodeCompletionReached() {
 
    assert(isCodeCompletionEnabled() && "Code-completion not enabled!");
 
    CodeCompletionReached = true;
 
    // Silence any diagnostics that occur after we hit the code-completion.
 
    getDiagnostics().setSuppressAllDiagnostics(true);
 
  }
 
 
 
  /// The location of the currently-active \#pragma clang
 
  /// arc_cf_code_audited begin.
 
  ///
 
  /// Returns an invalid location if there is no such pragma active.
 
  std::pair<IdentifierInfo *, SourceLocation>
 
  getPragmaARCCFCodeAuditedInfo() const {
 
    return PragmaARCCFCodeAuditedInfo;
 
  }
 
 
 
  /// Set the location of the currently-active \#pragma clang
 
  /// arc_cf_code_audited begin.  An invalid location ends the pragma.
 
  void setPragmaARCCFCodeAuditedInfo(IdentifierInfo *Ident,
 
                                     SourceLocation Loc) {
 
    PragmaARCCFCodeAuditedInfo = {Ident, Loc};
 
  }
 
 
 
  /// The location of the currently-active \#pragma clang
 
  /// assume_nonnull begin.
 
  ///
 
  /// Returns an invalid location if there is no such pragma active.
 
  SourceLocation getPragmaAssumeNonNullLoc() const {
 
    return PragmaAssumeNonNullLoc;
 
  }
 
 
 
  /// Set the location of the currently-active \#pragma clang
 
  /// assume_nonnull begin.  An invalid location ends the pragma.
 
  void setPragmaAssumeNonNullLoc(SourceLocation Loc) {
 
    PragmaAssumeNonNullLoc = Loc;
 
  }
 
 
 
  /// Get the location of the recorded unterminated \#pragma clang
 
  /// assume_nonnull begin in the preamble, if one exists.
 
  ///
 
  /// Returns an invalid location if the premable did not end with
 
  /// such a pragma active or if there is no recorded preamble.
 
  SourceLocation getPreambleRecordedPragmaAssumeNonNullLoc() const {
 
    return PreambleRecordedPragmaAssumeNonNullLoc;
 
  }
 
 
 
  /// Record the location of the unterminated \#pragma clang
 
  /// assume_nonnull begin in the preamble.
 
  void setPreambleRecordedPragmaAssumeNonNullLoc(SourceLocation Loc) {
 
    PreambleRecordedPragmaAssumeNonNullLoc = Loc;
 
  }
 
 
 
  /// Set the directory in which the main file should be considered
 
  /// to have been found, if it is not a real file.
 
  void setMainFileDir(const DirectoryEntry *Dir) {
 
    MainFileDir = Dir;
 
  }
 
 
 
  /// Instruct the preprocessor to skip part of the main source file.
 
  ///
 
  /// \param Bytes The number of bytes in the preamble to skip.
 
  ///
 
  /// \param StartOfLine Whether skipping these bytes puts the lexer at the
 
  /// start of a line.
 
  void setSkipMainFilePreamble(unsigned Bytes, bool StartOfLine) {
 
    SkipMainFilePreamble.first = Bytes;
 
    SkipMainFilePreamble.second = StartOfLine;
 
  }
 
 
 
  /// Forwarding function for diagnostics.  This emits a diagnostic at
 
  /// the specified Token's location, translating the token's start
 
  /// position in the current buffer into a SourcePosition object for rendering.
 
  DiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) const {
 
    return Diags->Report(Loc, DiagID);
 
  }
 
 
 
  DiagnosticBuilder Diag(const Token &Tok, unsigned DiagID) const {
 
    return Diags->Report(Tok.getLocation(), DiagID);
 
  }
 
 
 
  /// Return the 'spelling' of the token at the given
 
  /// location; does not go up to the spelling location or down to the
 
  /// expansion location.
 
  ///
 
  /// \param buffer A buffer which will be used only if the token requires
 
  ///   "cleaning", e.g. if it contains trigraphs or escaped newlines
 
  /// \param invalid If non-null, will be set \c true if an error occurs.
 
  StringRef getSpelling(SourceLocation loc,
 
                        SmallVectorImpl<char> &buffer,
 
                        bool *invalid = nullptr) const {
 
    return Lexer::getSpelling(loc, buffer, SourceMgr, LangOpts, invalid);
 
  }
 
 
 
  /// Return the 'spelling' of the Tok token.
 
  ///
 
  /// The spelling of a token is the characters used to represent the token in
 
  /// the source file after trigraph expansion and escaped-newline folding.  In
 
  /// particular, this wants to get the true, uncanonicalized, spelling of
 
  /// things like digraphs, UCNs, etc.
 
  ///
 
  /// \param Invalid If non-null, will be set \c true if an error occurs.
 
  std::string getSpelling(const Token &Tok, bool *Invalid = nullptr) const {
 
    return Lexer::getSpelling(Tok, SourceMgr, LangOpts, Invalid);
 
  }
 
 
 
  /// Get the spelling of a token into a preallocated buffer, instead
 
  /// of as an std::string.
 
  ///
 
  /// The caller is required to allocate enough space for the token, which is
 
  /// guaranteed to be at least Tok.getLength() bytes long. The length of the
 
  /// actual result is returned.
 
  ///
 
  /// Note that this method may do two possible things: it may either fill in
 
  /// the buffer specified with characters, or it may *change the input pointer*
 
  /// to point to a constant buffer with the data already in it (avoiding a
 
  /// copy).  The caller is not allowed to modify the returned buffer pointer
 
  /// if an internal buffer is returned.
 
  unsigned getSpelling(const Token &Tok, const char *&Buffer,
 
                       bool *Invalid = nullptr) const {
 
    return Lexer::getSpelling(Tok, Buffer, SourceMgr, LangOpts, Invalid);
 
  }
 
 
 
  /// Get the spelling of a token into a SmallVector.
 
  ///
 
  /// Note that the returned StringRef may not point to the
 
  /// supplied buffer if a copy can be avoided.
 
  StringRef getSpelling(const Token &Tok,
 
                        SmallVectorImpl<char> &Buffer,
 
                        bool *Invalid = nullptr) const;
 
 
 
  /// Relex the token at the specified location.
 
  /// \returns true if there was a failure, false on success.
 
  bool getRawToken(SourceLocation Loc, Token &Result,
 
                   bool IgnoreWhiteSpace = false) {
 
    return Lexer::getRawToken(Loc, Result, SourceMgr, LangOpts, IgnoreWhiteSpace);
 
  }
 
 
 
  /// Given a Token \p Tok that is a numeric constant with length 1,
 
  /// return the character.
 
  char
 
  getSpellingOfSingleCharacterNumericConstant(const Token &Tok,
 
                                              bool *Invalid = nullptr) const {
 
    assert(Tok.is(tok::numeric_constant) &&
 
           Tok.getLength() == 1 && "Called on unsupported token");
 
    assert(!Tok.needsCleaning() && "Token can't need cleaning with length 1");
 
 
 
    // If the token is carrying a literal data pointer, just use it.
 
    if (const char *D = Tok.getLiteralData())
 
      return *D;
 
 
 
    // Otherwise, fall back on getCharacterData, which is slower, but always
 
    // works.
 
    return *SourceMgr.getCharacterData(Tok.getLocation(), Invalid);
 
  }
 
 
 
  /// Retrieve the name of the immediate macro expansion.
 
  ///
 
  /// This routine starts from a source location, and finds the name of the
 
  /// macro responsible for its immediate expansion. It looks through any
 
  /// intervening macro argument expansions to compute this. It returns a
 
  /// StringRef that refers to the SourceManager-owned buffer of the source
 
  /// where that macro name is spelled. Thus, the result shouldn't out-live
 
  /// the SourceManager.
 
  StringRef getImmediateMacroName(SourceLocation Loc) {
 
    return Lexer::getImmediateMacroName(Loc, SourceMgr, getLangOpts());
 
  }
 
 
 
  /// Plop the specified string into a scratch buffer and set the
 
  /// specified token's location and length to it.
 
  ///
 
  /// If specified, the source location provides a location of the expansion
 
  /// point of the token.
 
  void CreateString(StringRef Str, Token &Tok,
 
                    SourceLocation ExpansionLocStart = SourceLocation(),
 
                    SourceLocation ExpansionLocEnd = SourceLocation());
 
 
 
  /// Split the first Length characters out of the token starting at TokLoc
 
  /// and return a location pointing to the split token. Re-lexing from the
 
  /// split token will return the split token rather than the original.
 
  SourceLocation SplitToken(SourceLocation TokLoc, unsigned Length);
 
 
 
  /// Computes the source location just past the end of the
 
  /// token at this source location.
 
  ///
 
  /// This routine can be used to produce a source location that
 
  /// points just past the end of the token referenced by \p Loc, and
 
  /// is generally used when a diagnostic needs to point just after a
 
  /// token where it expected something different that it received. If
 
  /// the returned source location would not be meaningful (e.g., if
 
  /// it points into a macro), this routine returns an invalid
 
  /// source location.
 
  ///
 
  /// \param Offset an offset from the end of the token, where the source
 
  /// location should refer to. The default offset (0) produces a source
 
  /// location pointing just past the end of the token; an offset of 1 produces
 
  /// a source location pointing to the last character in the token, etc.
 
  SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset = 0) {
 
    return Lexer::getLocForEndOfToken(Loc, Offset, SourceMgr, LangOpts);
 
  }
 
 
 
  /// Returns true if the given MacroID location points at the first
 
  /// token of the macro expansion.
 
  ///
 
  /// \param MacroBegin If non-null and function returns true, it is set to
 
  /// begin location of the macro.
 
  bool isAtStartOfMacroExpansion(SourceLocation loc,
 
                                 SourceLocation *MacroBegin = nullptr) const {
 
    return Lexer::isAtStartOfMacroExpansion(loc, SourceMgr, LangOpts,
 
                                            MacroBegin);
 
  }
 
 
 
  /// Returns true if the given MacroID location points at the last
 
  /// token of the macro expansion.
 
  ///
 
  /// \param MacroEnd If non-null and function returns true, it is set to
 
  /// end location of the macro.
 
  bool isAtEndOfMacroExpansion(SourceLocation loc,
 
                               SourceLocation *MacroEnd = nullptr) const {
 
    return Lexer::isAtEndOfMacroExpansion(loc, SourceMgr, LangOpts, MacroEnd);
 
  }
 
 
 
  /// Print the token to stderr, used for debugging.
 
  void DumpToken(const Token &Tok, bool DumpFlags = false) const;
 
  void DumpLocation(SourceLocation Loc) const;
 
  void DumpMacro(const MacroInfo &MI) const;
 
  void dumpMacroInfo(const IdentifierInfo *II);
 
 
 
  /// Given a location that specifies the start of a
 
  /// token, return a new location that specifies a character within the token.
 
  SourceLocation AdvanceToTokenCharacter(SourceLocation TokStart,
 
                                         unsigned Char) const {
 
    return Lexer::AdvanceToTokenCharacter(TokStart, Char, SourceMgr, LangOpts);
 
  }
 
 
 
  /// Increment the counters for the number of token paste operations
 
  /// performed.
 
  ///
 
  /// If fast was specified, this is a 'fast paste' case we handled.
 
  void IncrementPasteCounter(bool isFast) {
 
    if (isFast)
 
      ++NumFastTokenPaste;
 
    else
 
      ++NumTokenPaste;
 
  }
 
 
 
  void PrintStats();
 
 
 
  size_t getTotalMemory() const;
 
 
 
  /// When the macro expander pastes together a comment (/##/) in Microsoft
 
  /// mode, this method handles updating the current state, returning the
 
  /// token on the next source line.
 
  void HandleMicrosoftCommentPaste(Token &Tok);
 
 
 
  //===--------------------------------------------------------------------===//
 
  // Preprocessor callback methods.  These are invoked by a lexer as various
 
  // directives and events are found.
 
 
 
  /// Given a tok::raw_identifier token, look up the
 
  /// identifier information for the token and install it into the token,
 
  /// updating the token kind accordingly.
 
  IdentifierInfo *LookUpIdentifierInfo(Token &Identifier) const;
 
 
 
private:
 
  llvm::DenseMap<IdentifierInfo*,unsigned> PoisonReasons;
 
 
 
public:
 
  /// Specifies the reason for poisoning an identifier.
 
  ///
 
  /// If that identifier is accessed while poisoned, then this reason will be
 
  /// used instead of the default "poisoned" diagnostic.
 
  void SetPoisonReason(IdentifierInfo *II, unsigned DiagID);
 
 
 
  /// Display reason for poisoned identifier.
 
  void HandlePoisonedIdentifier(Token & Identifier);
 
 
 
  void MaybeHandlePoisonedIdentifier(Token & Identifier) {
 
    if(IdentifierInfo * II = Identifier.getIdentifierInfo()) {
 
      if(II->isPoisoned()) {
 
        HandlePoisonedIdentifier(Identifier);
 
      }
 
    }
 
  }
 
 
 
private:
 
  /// Identifiers used for SEH handling in Borland. These are only
 
  /// allowed in particular circumstances
 
  // __except block
 
  IdentifierInfo *Ident__exception_code,
 
                 *Ident___exception_code,
 
                 *Ident_GetExceptionCode;
 
  // __except filter expression
 
  IdentifierInfo *Ident__exception_info,
 
                 *Ident___exception_info,
 
                 *Ident_GetExceptionInfo;
 
  // __finally
 
  IdentifierInfo *Ident__abnormal_termination,
 
                 *Ident___abnormal_termination,
 
                 *Ident_AbnormalTermination;
 
 
 
  const char *getCurLexerEndPos();
 
  void diagnoseMissingHeaderInUmbrellaDir(const Module &Mod);
 
 
 
public:
 
  void PoisonSEHIdentifiers(bool Poison = true); // Borland
 
 
 
  /// Callback invoked when the lexer reads an identifier and has
 
  /// filled in the tokens IdentifierInfo member.
 
  ///
 
  /// This callback potentially macro expands it or turns it into a named
 
  /// token (like 'for').
 
  ///
 
  /// \returns true if we actually computed a token, false if we need to
 
  /// lex again.
 
  bool HandleIdentifier(Token &Identifier);
 
 
 
  /// Callback invoked when the lexer hits the end of the current file.
 
  ///
 
  /// This either returns the EOF token and returns true, or
 
  /// pops a level off the include stack and returns false, at which point the
 
  /// client should call lex again.
 
  bool HandleEndOfFile(Token &Result, bool isEndOfMacro = false);
 
 
 
  /// Callback invoked when the current TokenLexer hits the end of its
 
  /// token stream.
 
  bool HandleEndOfTokenLexer(Token &Result);
 
 
 
  /// Callback invoked when the lexer sees a # token at the start of a
 
  /// line.
 
  ///
 
  /// This consumes the directive, modifies the lexer/preprocessor state, and
 
  /// advances the lexer(s) so that the next token read is the correct one.
 
  void HandleDirective(Token &Result);
 
 
 
  /// Ensure that the next token is a tok::eod token.
 
  ///
 
  /// If not, emit a diagnostic and consume up until the eod.
 
  /// If \p EnableMacros is true, then we consider macros that expand to zero
 
  /// tokens as being ok.
 
  ///
 
  /// \return The location of the end of the directive (the terminating
 
  /// newline).
 
  SourceLocation CheckEndOfDirective(const char *DirType,
 
                                     bool EnableMacros = false);
 
 
 
  /// Read and discard all tokens remaining on the current line until
 
  /// the tok::eod token is found. Returns the range of the skipped tokens.
 
  SourceRange DiscardUntilEndOfDirective();
 
 
 
  /// Returns true if the preprocessor has seen a use of
 
  /// __DATE__ or __TIME__ in the file so far.
 
  bool SawDateOrTime() const {
 
    return DATELoc != SourceLocation() || TIMELoc != SourceLocation();
 
  }
 
  unsigned getCounterValue() const { return CounterValue; }
 
  void setCounterValue(unsigned V) { CounterValue = V; }
 
 
 
  LangOptions::FPEvalMethodKind getCurrentFPEvalMethod() const {
 
    assert(CurrentFPEvalMethod != LangOptions::FEM_UnsetOnCommandLine &&
 
           "FPEvalMethod should be set either from command line or from the "
 
           "target info");
 
    return CurrentFPEvalMethod;
 
  }
 
 
 
  LangOptions::FPEvalMethodKind getTUFPEvalMethod() const {
 
    return TUFPEvalMethod;
 
  }
 
 
 
  SourceLocation getLastFPEvalPragmaLocation() const {
 
    return LastFPEvalPragmaLocation;
 
  }
 
 
 
  void setCurrentFPEvalMethod(SourceLocation PragmaLoc,
 
                              LangOptions::FPEvalMethodKind Val) {
 
    assert(Val != LangOptions::FEM_UnsetOnCommandLine &&
 
           "FPEvalMethod should never be set to FEM_UnsetOnCommandLine");
 
    // This is the location of the '#pragma float_control" where the
 
    // execution state is modifed.
 
    LastFPEvalPragmaLocation = PragmaLoc;
 
    CurrentFPEvalMethod = Val;
 
    TUFPEvalMethod = Val;
 
  }
 
 
 
  void setTUFPEvalMethod(LangOptions::FPEvalMethodKind Val) {
 
    assert(Val != LangOptions::FEM_UnsetOnCommandLine &&
 
           "TUPEvalMethod should never be set to FEM_UnsetOnCommandLine");
 
    TUFPEvalMethod = Val;
 
  }
 
 
 
  /// Retrieves the module that we're currently building, if any.
 
  Module *getCurrentModule();
 
 
 
  /// Retrieves the module whose implementation we're current compiling, if any.
 
  Module *getCurrentModuleImplementation();
 
 
 
  /// If we are preprocessing a named module.
 
  bool isInNamedModule() const { return ModuleDeclState.isNamedModule(); }
 
 
 
  /// If we are proprocessing a named interface unit.
 
  /// Note that a module implementation partition is not considered as an
 
  /// named interface unit here although it is importable
 
  /// to ease the parsing.
 
  bool isInNamedInterfaceUnit() const {
 
    return ModuleDeclState.isNamedInterface();
 
  }
 
 
 
  /// Get the named module name we're preprocessing.
 
  /// Requires we're preprocessing a named module.
 
  StringRef getNamedModuleName() const { return ModuleDeclState.getName(); }
 
 
 
  /// If we are implementing an implementation module unit.
 
  /// Note that the module implementation partition is not considered as an
 
  /// implementation unit.
 
  bool isInImplementationUnit() const {
 
    return ModuleDeclState.isImplementationUnit();
 
  }
 
 
 
  /// If we're importing a standard C++20 Named Modules.
 
  bool isInImportingCXXNamedModules() const {
 
    // NamedModuleImportPath will be non-empty only if we're importing
 
    // Standard C++ named modules.
 
    return !NamedModuleImportPath.empty() && getLangOpts().CPlusPlusModules &&
 
           !IsAtImport;
 
  }
 
 
 
  /// Allocate a new MacroInfo object with the provided SourceLocation.
 
  MacroInfo *AllocateMacroInfo(SourceLocation L);
 
 
 
  /// Turn the specified lexer token into a fully checked and spelled
 
  /// filename, e.g. as an operand of \#include.
 
  ///
 
  /// The caller is expected to provide a buffer that is large enough to hold
 
  /// the spelling of the filename, but is also expected to handle the case
 
  /// when this method decides to use a different buffer.
 
  ///
 
  /// \returns true if the input filename was in <>'s or false if it was
 
  /// in ""'s.
 
  bool GetIncludeFilenameSpelling(SourceLocation Loc,StringRef &Buffer);
 
 
 
  /// Given a "foo" or \<foo> reference, look up the indicated file.
 
  ///
 
  /// Returns std::nullopt on failure.  \p isAngled indicates whether the file
 
  /// reference is for system \#include's or not (i.e. using <> instead of "").
 
  OptionalFileEntryRef
 
  LookupFile(SourceLocation FilenameLoc, StringRef Filename, bool isAngled,
 
             ConstSearchDirIterator FromDir, const FileEntry *FromFile,
 
             ConstSearchDirIterator *CurDir, SmallVectorImpl<char> *SearchPath,
 
             SmallVectorImpl<char> *RelativePath,
 
             ModuleMap::KnownHeader *SuggestedModule, bool *IsMapped,
 
             bool *IsFrameworkFound, bool SkipCache = false,
 
             bool OpenFile = true, bool CacheFailures = true);
 
 
 
  /// Return true if we're in the top-level file, not in a \#include.
 
  bool isInPrimaryFile() const;
 
 
 
  /// Lex an on-off-switch (C99 6.10.6p2) and verify that it is
 
  /// followed by EOD.  Return true if the token is not a valid on-off-switch.
 
  bool LexOnOffSwitch(tok::OnOffSwitch &Result);
 
 
 
  bool CheckMacroName(Token &MacroNameTok, MacroUse isDefineUndef,
 
                      bool *ShadowFlag = nullptr);
 
 
 
  void EnterSubmodule(Module *M, SourceLocation ImportLoc, bool ForPragma);
 
  Module *LeaveSubmodule(bool ForPragma);
 
 
 
private:
 
  friend void TokenLexer::ExpandFunctionArguments();
 
 
 
  void PushIncludeMacroStack() {
 
    assert(CurLexerKind != CLK_CachingLexer && "cannot push a caching lexer");
 
    IncludeMacroStack.emplace_back(CurLexerKind, CurLexerSubmodule,
 
                                   std::move(CurLexer), CurPPLexer,
 
                                   std::move(CurTokenLexer), CurDirLookup);
 
    CurPPLexer = nullptr;
 
  }
 
 
 
  void PopIncludeMacroStack() {
 
    CurLexer = std::move(IncludeMacroStack.back().TheLexer);
 
    CurPPLexer = IncludeMacroStack.back().ThePPLexer;
 
    CurTokenLexer = std::move(IncludeMacroStack.back().TheTokenLexer);
 
    CurDirLookup  = IncludeMacroStack.back().TheDirLookup;
 
    CurLexerSubmodule = IncludeMacroStack.back().TheSubmodule;
 
    CurLexerKind = IncludeMacroStack.back().CurLexerKind;
 
    IncludeMacroStack.pop_back();
 
  }
 
 
 
  void PropagateLineStartLeadingSpaceInfo(Token &Result);
 
 
 
  /// Determine whether we need to create module macros for #defines in the
 
  /// current context.
 
  bool needModuleMacros() const;
 
 
 
  /// Update the set of active module macros and ambiguity flag for a module
 
  /// macro name.
 
  void updateModuleMacroInfo(const IdentifierInfo *II, ModuleMacroInfo &Info);
 
 
 
  DefMacroDirective *AllocateDefMacroDirective(MacroInfo *MI,
 
                                               SourceLocation Loc);
 
  UndefMacroDirective *AllocateUndefMacroDirective(SourceLocation UndefLoc);
 
  VisibilityMacroDirective *AllocateVisibilityMacroDirective(SourceLocation Loc,
 
                                                             bool isPublic);
 
 
 
  /// Lex and validate a macro name, which occurs after a
 
  /// \#define or \#undef.
 
  ///
 
  /// \param MacroNameTok Token that represents the name defined or undefined.
 
  /// \param IsDefineUndef Kind if preprocessor directive.
 
  /// \param ShadowFlag Points to flag that is set if macro name shadows
 
  ///                   a keyword.
 
  ///
 
  /// This emits a diagnostic, sets the token kind to eod,
 
  /// and discards the rest of the macro line if the macro name is invalid.
 
  void ReadMacroName(Token &MacroNameTok, MacroUse IsDefineUndef = MU_Other,
 
                     bool *ShadowFlag = nullptr);
 
 
 
  /// ReadOptionalMacroParameterListAndBody - This consumes all (i.e. the
 
  /// entire line) of the macro's tokens and adds them to MacroInfo, and while
 
  /// doing so performs certain validity checks including (but not limited to):
 
  ///   - # (stringization) is followed by a macro parameter
 
  /// \param MacroNameTok - Token that represents the macro name
 
  /// \param ImmediatelyAfterHeaderGuard - Macro follows an #ifdef header guard
 
  ///
 
  ///  Either returns a pointer to a MacroInfo object OR emits a diagnostic and
 
  ///  returns a nullptr if an invalid sequence of tokens is encountered.
 
  MacroInfo *ReadOptionalMacroParameterListAndBody(
 
      const Token &MacroNameTok, bool ImmediatelyAfterHeaderGuard);
 
 
 
  /// The ( starting an argument list of a macro definition has just been read.
 
  /// Lex the rest of the parameters and the closing ), updating \p MI with
 
  /// what we learn and saving in \p LastTok the last token read.
 
  /// Return true if an error occurs parsing the arg list.
 
  bool ReadMacroParameterList(MacroInfo *MI, Token& LastTok);
 
 
 
  /// Provide a suggestion for a typoed directive. If there is no typo, then
 
  /// just skip suggesting.
 
  ///
 
  /// \param Tok - Token that represents the directive
 
  /// \param Directive - String reference for the directive name
 
  void SuggestTypoedDirective(const Token &Tok, StringRef Directive) const;
 
 
 
  /// We just read a \#if or related directive and decided that the
 
  /// subsequent tokens are in the \#if'd out portion of the
 
  /// file.  Lex the rest of the file, until we see an \#endif.  If \p
 
  /// FoundNonSkipPortion is true, then we have already emitted code for part of
 
  /// this \#if directive, so \#else/\#elif blocks should never be entered. If
 
  /// \p FoundElse is false, then \#else directives are ok, if not, then we have
 
  /// already seen one so a \#else directive is a duplicate.  When this returns,
 
  /// the caller can lex the first valid token.
 
  void SkipExcludedConditionalBlock(SourceLocation HashTokenLoc,
 
                                    SourceLocation IfTokenLoc,
 
                                    bool FoundNonSkipPortion, bool FoundElse,
 
                                    SourceLocation ElseLoc = SourceLocation());
 
 
 
  /// Information about the result for evaluating an expression for a
 
  /// preprocessor directive.
 
  struct DirectiveEvalResult {
 
    /// Whether the expression was evaluated as true or not.
 
    bool Conditional;
 
 
 
    /// True if the expression contained identifiers that were undefined.
 
    bool IncludedUndefinedIds;
 
 
 
    /// The source range for the expression.
 
    SourceRange ExprRange;
 
  };
 
 
 
  /// Evaluate an integer constant expression that may occur after a
 
  /// \#if or \#elif directive and return a \p DirectiveEvalResult object.
 
  ///
 
  /// If the expression is equivalent to "!defined(X)" return X in IfNDefMacro.
 
  DirectiveEvalResult EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro);
 
 
 
  /// Process a '__has_include("path")' expression.
 
  ///
 
  /// Returns true if successful.
 
  bool EvaluateHasInclude(Token &Tok, IdentifierInfo *II);
 
 
 
  /// Process '__has_include_next("path")' expression.
 
  ///
 
  /// Returns true if successful.
 
  bool EvaluateHasIncludeNext(Token &Tok, IdentifierInfo *II);
 
 
 
  /// Get the directory and file from which to start \#include_next lookup.
 
  std::pair<ConstSearchDirIterator, const FileEntry *>
 
  getIncludeNextStart(const Token &IncludeNextTok) const;
 
 
 
  /// Install the standard preprocessor pragmas:
 
  /// \#pragma GCC poison/system_header/dependency and \#pragma once.
 
  void RegisterBuiltinPragmas();
 
 
 
  /// Register builtin macros such as __LINE__ with the identifier table.
 
  void RegisterBuiltinMacros();
 
 
 
  /// If an identifier token is read that is to be expanded as a macro, handle
 
  /// it and return the next token as 'Tok'.  If we lexed a token, return true;
 
  /// otherwise the caller should lex again.
 
  bool HandleMacroExpandedIdentifier(Token &Identifier, const MacroDefinition &MD);
 
 
 
  /// Cache macro expanded tokens for TokenLexers.
 
  //
 
  /// Works like a stack; a TokenLexer adds the macro expanded tokens that is
 
  /// going to lex in the cache and when it finishes the tokens are removed
 
  /// from the end of the cache.
 
  Token *cacheMacroExpandedTokens(TokenLexer *tokLexer,
 
                                  ArrayRef<Token> tokens);
 
 
 
  void removeCachedMacroExpandedTokensOfLastLexer();
 
 
 
  /// Determine whether the next preprocessor token to be
 
  /// lexed is a '('.  If so, consume the token and return true, if not, this
 
  /// method should have no observable side-effect on the lexed tokens.
 
  bool isNextPPTokenLParen();
 
 
 
  /// After reading "MACRO(", this method is invoked to read all of the formal
 
  /// arguments specified for the macro invocation.  Returns null on error.
 
  MacroArgs *ReadMacroCallArgumentList(Token &MacroName, MacroInfo *MI,
 
                                       SourceLocation &MacroEnd);
 
 
 
  /// If an identifier token is read that is to be expanded
 
  /// as a builtin macro, handle it and return the next token as 'Tok'.
 
  void ExpandBuiltinMacro(Token &Tok);
 
 
 
  /// Read a \c _Pragma directive, slice it up, process it, then
 
  /// return the first token after the directive.
 
  /// This assumes that the \c _Pragma token has just been read into \p Tok.
 
  void Handle_Pragma(Token &Tok);
 
 
 
  /// Like Handle_Pragma except the pragma text is not enclosed within
 
  /// a string literal.
 
  void HandleMicrosoft__pragma(Token &Tok);
 
 
 
  /// Add a lexer to the top of the include stack and
 
  /// start lexing tokens from it instead of the current buffer.
 
  void EnterSourceFileWithLexer(Lexer *TheLexer, ConstSearchDirIterator Dir);
 
 
 
  /// Set the FileID for the preprocessor predefines.
 
  void setPredefinesFileID(FileID FID) {
 
    assert(PredefinesFileID.isInvalid() && "PredefinesFileID already set!");
 
    PredefinesFileID = FID;
 
  }
 
 
 
  /// Set the FileID for the PCH through header.
 
  void setPCHThroughHeaderFileID(FileID FID);
 
 
 
  /// Returns true if we are lexing from a file and not a
 
  /// pragma or a macro.
 
  static bool IsFileLexer(const Lexer* L, const PreprocessorLexer* P) {
 
    return L ? !L->isPragmaLexer() : P != nullptr;
 
  }
 
 
 
  static bool IsFileLexer(const IncludeStackInfo& I) {
 
    return IsFileLexer(I.TheLexer.get(), I.ThePPLexer);
 
  }
 
 
 
  bool IsFileLexer() const {
 
    return IsFileLexer(CurLexer.get(), CurPPLexer);
 
  }
 
 
 
  //===--------------------------------------------------------------------===//
 
  // Caching stuff.
 
  void CachingLex(Token &Result);
 
 
 
  bool InCachingLexMode() const {
 
    // If the Lexer pointers are 0 and IncludeMacroStack is empty, it means
 
    // that we are past EOF, not that we are in CachingLex mode.
 
    return !CurPPLexer && !CurTokenLexer && !IncludeMacroStack.empty();
 
  }
 
 
 
  void EnterCachingLexMode();
 
  void EnterCachingLexModeUnchecked();
 
 
 
  void ExitCachingLexMode() {
 
    if (InCachingLexMode())
 
      RemoveTopOfLexerStack();
 
  }
 
 
 
  const Token &PeekAhead(unsigned N);
 
  void AnnotatePreviousCachedTokens(const Token &Tok);
 
 
 
  //===--------------------------------------------------------------------===//
 
  /// Handle*Directive - implement the various preprocessor directives.  These
 
  /// should side-effect the current preprocessor object so that the next call
 
  /// to Lex() will return the appropriate token next.
 
  void HandleLineDirective();
 
  void HandleDigitDirective(Token &Tok);
 
  void HandleUserDiagnosticDirective(Token &Tok, bool isWarning);
 
  void HandleIdentSCCSDirective(Token &Tok);
 
  void HandleMacroPublicDirective(Token &Tok);
 
  void HandleMacroPrivateDirective();
 
 
 
  /// An additional notification that can be produced by a header inclusion or
 
  /// import to tell the parser what happened.
 
  struct ImportAction {
 
    enum ActionKind {
 
      None,
 
      ModuleBegin,
 
      ModuleImport,
 
      HeaderUnitImport,
 
      SkippedModuleImport,
 
      Failure,
 
    } Kind;
 
    Module *ModuleForHeader = nullptr;
 
 
 
    ImportAction(ActionKind AK, Module *Mod = nullptr)
 
        : Kind(AK), ModuleForHeader(Mod) {
 
      assert((AK == None || Mod || AK == Failure) &&
 
             "no module for module action");
 
    }
 
  };
 
 
 
  OptionalFileEntryRef LookupHeaderIncludeOrImport(
 
      ConstSearchDirIterator *CurDir, StringRef &Filename,
 
      SourceLocation FilenameLoc, CharSourceRange FilenameRange,
 
      const Token &FilenameTok, bool &IsFrameworkFound, bool IsImportDecl,
 
      bool &IsMapped, ConstSearchDirIterator LookupFrom,
 
      const FileEntry *LookupFromFile, StringRef &LookupFilename,
 
      SmallVectorImpl<char> &RelativePath, SmallVectorImpl<char> &SearchPath,
 
      ModuleMap::KnownHeader &SuggestedModule, bool isAngled);
 
 
 
  // File inclusion.
 
  void HandleIncludeDirective(SourceLocation HashLoc, Token &Tok,
 
                              ConstSearchDirIterator LookupFrom = nullptr,
 
                              const FileEntry *LookupFromFile = nullptr);
 
  ImportAction
 
  HandleHeaderIncludeOrImport(SourceLocation HashLoc, Token &IncludeTok,
 
                              Token &FilenameTok, SourceLocation EndLoc,
 
                              ConstSearchDirIterator LookupFrom = nullptr,
 
                              const FileEntry *LookupFromFile = nullptr);
 
  void HandleIncludeNextDirective(SourceLocation HashLoc, Token &Tok);
 
  void HandleIncludeMacrosDirective(SourceLocation HashLoc, Token &Tok);
 
  void HandleImportDirective(SourceLocation HashLoc, Token &Tok);
 
  void HandleMicrosoftImportDirective(Token &Tok);
 
 
 
public:
 
  /// Check that the given module is available, producing a diagnostic if not.
 
  /// \return \c true if the check failed (because the module is not available).
 
  ///         \c false if the module appears to be usable.
 
  static bool checkModuleIsAvailable(const LangOptions &LangOpts,
 
                                     const TargetInfo &TargetInfo,
 
                                     DiagnosticsEngine &Diags, Module *M);
 
 
 
  // Module inclusion testing.
 
  /// Find the module that owns the source or header file that
 
  /// \p Loc points to. If the location is in a file that was included
 
  /// into a module, or is outside any module, returns nullptr.
 
  Module *getModuleForLocation(SourceLocation Loc, bool AllowTextual);
 
 
 
  /// We want to produce a diagnostic at location IncLoc concerning an
 
  /// unreachable effect at location MLoc (eg, where a desired entity was
 
  /// declared or defined). Determine whether the right way to make MLoc
 
  /// reachable is by #include, and if so, what header should be included.
 
  ///
 
  /// This is not necessarily fast, and might load unexpected module maps, so
 
  /// should only be called by code that intends to produce an error.
 
  ///
 
  /// \param IncLoc The location at which the missing effect was detected.
 
  /// \param MLoc A location within an unimported module at which the desired
 
  ///        effect occurred.
 
  /// \return A file that can be #included to provide the desired effect. Null
 
  ///         if no such file could be determined or if a #include is not
 
  ///         appropriate (eg, if a module should be imported instead).
 
  const FileEntry *getHeaderToIncludeForDiagnostics(SourceLocation IncLoc,
 
                                                    SourceLocation MLoc);
 
 
 
  bool isRecordingPreamble() const {
 
    return PreambleConditionalStack.isRecording();
 
  }
 
 
 
  bool hasRecordedPreamble() const {
 
    return PreambleConditionalStack.hasRecordedPreamble();
 
  }
 
 
 
  ArrayRef<PPConditionalInfo> getPreambleConditionalStack() const {
 
      return PreambleConditionalStack.getStack();
 
  }
 
 
 
  void setRecordedPreambleConditionalStack(ArrayRef<PPConditionalInfo> s) {
 
    PreambleConditionalStack.setStack(s);
 
  }
 
 
 
  void setReplayablePreambleConditionalStack(
 
      ArrayRef<PPConditionalInfo> s, std::optional<PreambleSkipInfo> SkipInfo) {
 
    PreambleConditionalStack.startReplaying();
 
    PreambleConditionalStack.setStack(s);
 
    PreambleConditionalStack.SkipInfo = SkipInfo;
 
  }
 
 
 
  std::optional<PreambleSkipInfo> getPreambleSkipInfo() const {
 
    return PreambleConditionalStack.SkipInfo;
 
  }
 
 
 
private:
 
  /// After processing predefined file, initialize the conditional stack from
 
  /// the preamble.
 
  void replayPreambleConditionalStack();
 
 
 
  // Macro handling.
 
  void HandleDefineDirective(Token &Tok, bool ImmediatelyAfterHeaderGuard);
 
  void HandleUndefDirective();
 
 
 
  // Conditional Inclusion.
 
  void HandleIfdefDirective(Token &Result, const Token &HashToken,
 
                            bool isIfndef, bool ReadAnyTokensBeforeDirective);
 
  void HandleIfDirective(Token &IfToken, const Token &HashToken,
 
                         bool ReadAnyTokensBeforeDirective);
 
  void HandleEndifDirective(Token &EndifToken);
 
  void HandleElseDirective(Token &Result, const Token &HashToken);
 
  void HandleElifFamilyDirective(Token &ElifToken, const Token &HashToken,
 
                                 tok::PPKeywordKind Kind);
 
 
 
  // Pragmas.
 
  void HandlePragmaDirective(PragmaIntroducer Introducer);
 
 
 
public:
 
  void HandlePragmaOnce(Token &OnceTok);
 
  void HandlePragmaMark(Token &MarkTok);
 
  void HandlePragmaPoison();
 
  void HandlePragmaSystemHeader(Token &SysHeaderTok);
 
  void HandlePragmaDependency(Token &DependencyTok);
 
  void HandlePragmaPushMacro(Token &Tok);
 
  void HandlePragmaPopMacro(Token &Tok);
 
  void HandlePragmaIncludeAlias(Token &Tok);
 
  void HandlePragmaModuleBuild(Token &Tok);
 
  void HandlePragmaHdrstop(Token &Tok);
 
  IdentifierInfo *ParsePragmaPushOrPopMacro(Token &Tok);
 
 
 
  // Return true and store the first token only if any CommentHandler
 
  // has inserted some tokens and getCommentRetentionState() is false.
 
  bool HandleComment(Token &result, SourceRange Comment);
 
 
 
  /// A macro is used, update information about macros that need unused
 
  /// warnings.
 
  void markMacroAsUsed(MacroInfo *MI);
 
 
 
  void addMacroDeprecationMsg(const IdentifierInfo *II, std::string Msg,
 
                              SourceLocation AnnotationLoc) {
 
    auto Annotations = AnnotationInfos.find(II);
 
    if (Annotations == AnnotationInfos.end())
 
      AnnotationInfos.insert(std::make_pair(
 
          II,
 
          MacroAnnotations::makeDeprecation(AnnotationLoc, std::move(Msg))));
 
    else
 
      Annotations->second.DeprecationInfo =
 
          MacroAnnotationInfo{AnnotationLoc, std::move(Msg)};
 
  }
 
 
 
  void addRestrictExpansionMsg(const IdentifierInfo *II, std::string Msg,
 
                               SourceLocation AnnotationLoc) {
 
    auto Annotations = AnnotationInfos.find(II);
 
    if (Annotations == AnnotationInfos.end())
 
      AnnotationInfos.insert(
 
          std::make_pair(II, MacroAnnotations::makeRestrictExpansion(
 
                                 AnnotationLoc, std::move(Msg))));
 
    else
 
      Annotations->second.RestrictExpansionInfo =
 
          MacroAnnotationInfo{AnnotationLoc, std::move(Msg)};
 
  }
 
 
 
  void addFinalLoc(const IdentifierInfo *II, SourceLocation AnnotationLoc) {
 
    auto Annotations = AnnotationInfos.find(II);
 
    if (Annotations == AnnotationInfos.end())
 
      AnnotationInfos.insert(
 
          std::make_pair(II, MacroAnnotations::makeFinal(AnnotationLoc)));
 
    else
 
      Annotations->second.FinalAnnotationLoc = AnnotationLoc;
 
  }
 
 
 
  const MacroAnnotations &getMacroAnnotations(const IdentifierInfo *II) const {
 
    return AnnotationInfos.find(II)->second;
 
  }
 
 
 
  void emitMacroExpansionWarnings(const Token &Identifier) const {
 
    if (Identifier.getIdentifierInfo()->isDeprecatedMacro())
 
      emitMacroDeprecationWarning(Identifier);
 
 
 
    if (Identifier.getIdentifierInfo()->isRestrictExpansion() &&
 
        !SourceMgr.isInMainFile(Identifier.getLocation()))
 
      emitRestrictExpansionWarning(Identifier);
 
  }
 
 
 
  static void processPathForFileMacro(SmallVectorImpl<char> &Path,
 
                                      const LangOptions &LangOpts,
 
                                      const TargetInfo &TI);
 
 
 
private:
 
  void emitMacroDeprecationWarning(const Token &Identifier) const;
 
  void emitRestrictExpansionWarning(const Token &Identifier) const;
 
  void emitFinalMacroWarning(const Token &Identifier, bool IsUndef) const;
 
};
 
 
 
/// Abstract base class that describes a handler that will receive
 
/// source ranges for each of the comments encountered in the source file.
 
class CommentHandler {
 
public:
 
  virtual ~CommentHandler();
 
 
 
  // The handler shall return true if it has pushed any tokens
 
  // to be read using e.g. EnterToken or EnterTokenStream.
 
  virtual bool HandleComment(Preprocessor &PP, SourceRange Comment) = 0;
 
};
 
 
 
/// Abstract base class that describes a handler that will receive
 
/// source ranges for empty lines encountered in the source file.
 
class EmptylineHandler {
 
public:
 
  virtual ~EmptylineHandler();
 
 
 
  // The handler handles empty lines.
 
  virtual void HandleEmptyline(SourceRange Range) = 0;
 
};
 
 
 
/// Registry of pragma handlers added by plugins
 
using PragmaHandlerRegistry = llvm::Registry<PragmaHandler>;
 
 
 
} // namespace clang
 
 
 
#endif // LLVM_CLANG_LEX_PREPROCESSOR_H