Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- PreprocessingRecord.h - Record of Preprocessing ----------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

//  This file defines the PreprocessingRecord class, which maintains a record

//  of what occurred during preprocessing.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_LEX_PREPROCESSINGRECORD_H

#define LLVM_CLANG_LEX_PREPROCESSINGRECORD_H

#include "clang/Basic/IdentifierTable.h"

#include "clang/Basic/LLVM.h"

#include "clang/Basic/SourceLocation.h"

#include "clang/Lex/PPCallbacks.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/PointerUnion.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/iterator.h"

#include "llvm/ADT/iterator_range.h"

#include "llvm/Support/Allocator.h"

#include "llvm/Support/Compiler.h"

#include <cassert>

#include <cstddef>

#include <iterator>

#include <optional>

#include <utility>

#include <vector>

namespace clang {

class PreprocessingRecord;

} // namespace clang

/// Allocates memory within a Clang preprocessing record.

void *operator new(size_t bytes, clang::PreprocessingRecord &PR,

                   unsigned alignment = 8) noexcept;

/// Frees memory allocated in a Clang preprocessing record.

void operator delete(void *ptr, clang::PreprocessingRecord &PR,

                     unsigned) noexcept;

namespace clang {

class IdentifierInfo;

class MacroInfo;

class SourceManager;

class Token;

  /// Base class that describes a preprocessed entity, which may be a

  /// preprocessor directive or macro expansion.

  class PreprocessedEntity {

  public:

    /// The kind of preprocessed entity an object describes.

    enum EntityKind {

      /// Indicates a problem trying to load the preprocessed entity.

      InvalidKind,

      /// A macro expansion.

      MacroExpansionKind,

      /// \defgroup Preprocessing directives

      /// @{

      /// A macro definition.

      MacroDefinitionKind,

      /// An inclusion directive, such as \c \#include, \c

      /// \#import, or \c \#include_next.

      InclusionDirectiveKind,

      /// @}

      FirstPreprocessingDirective = MacroDefinitionKind,

      LastPreprocessingDirective = InclusionDirectiveKind

    };

  private:

    /// The kind of preprocessed entity that this object describes.

    EntityKind Kind;

    /// The source range that covers this preprocessed entity.

    SourceRange Range;

  protected:

    friend class PreprocessingRecord;

    PreprocessedEntity(EntityKind Kind, SourceRange Range)

        : Kind(Kind), Range(Range) {}

  public:

    /// Retrieve the kind of preprocessed entity stored in this object.

    EntityKind getKind() const { return Kind; }

    /// Retrieve the source range that covers this entire preprocessed

    /// entity.

    SourceRange getSourceRange() const LLVM_READONLY { return Range; }

    /// Returns true if there was a problem loading the preprocessed

    /// entity.

    bool isInvalid() const { return Kind == InvalidKind; }

    // Only allow allocation of preprocessed entities using the allocator

    // in PreprocessingRecord or by doing a placement new.

    void *operator new(size_t bytes, PreprocessingRecord &PR,

                       unsigned alignment = 8) noexcept {

      return ::operator new(bytes, PR, alignment);

    }

    void *operator new(size_t bytes, void *mem) noexcept { return mem; }

    void operator delete(void *ptr, PreprocessingRecord &PR,

                         unsigned alignment) noexcept {

      return ::operator delete(ptr, PR, alignment);

    }

    void operator delete(void *, std::size_t) noexcept {}

    void operator delete(void *, void *) noexcept {}

  private:

    // Make vanilla 'new' and 'delete' illegal for preprocessed entities.

    void *operator new(size_t bytes) noexcept;

    void operator delete(void *data) noexcept;

  };

  /// Records the presence of a preprocessor directive.

  class PreprocessingDirective : public PreprocessedEntity {

  public:

    PreprocessingDirective(EntityKind Kind, SourceRange Range)

        : PreprocessedEntity(Kind, Range) {}

    // Implement isa/cast/dyncast/etc.

    static bool classof(const PreprocessedEntity *PD) {

      return PD->getKind() >= FirstPreprocessingDirective &&

             PD->getKind() <= LastPreprocessingDirective;

    }

  };

  /// Record the location of a macro definition.

  class MacroDefinitionRecord : public PreprocessingDirective {

    /// The name of the macro being defined.

    const IdentifierInfo *Name;

  public:

    explicit MacroDefinitionRecord(const IdentifierInfo *Name,

                                   SourceRange Range)

        : PreprocessingDirective(MacroDefinitionKind, Range), Name(Name) {}

    /// Retrieve the name of the macro being defined.

    const IdentifierInfo *getName() const { return Name; }

    /// Retrieve the location of the macro name in the definition.

    SourceLocation getLocation() const { return getSourceRange().getBegin(); }

    // Implement isa/cast/dyncast/etc.

    static bool classof(const PreprocessedEntity *PE) {

      return PE->getKind() == MacroDefinitionKind;

    }

  };

  /// Records the location of a macro expansion.

  class MacroExpansion : public PreprocessedEntity {

    /// The definition of this macro or the name of the macro if it is

    /// a builtin macro.

    llvm::PointerUnion<IdentifierInfo *, MacroDefinitionRecord *> NameOrDef;

  public:

    MacroExpansion(IdentifierInfo *BuiltinName, SourceRange Range)

        : PreprocessedEntity(MacroExpansionKind, Range),

          NameOrDef(BuiltinName) {}

    MacroExpansion(MacroDefinitionRecord *Definition, SourceRange Range)

        : PreprocessedEntity(MacroExpansionKind, Range), NameOrDef(Definition) {

    }

    /// True if it is a builtin macro.

    bool isBuiltinMacro() const { return NameOrDef.is<IdentifierInfo *>(); }

    /// The name of the macro being expanded.

    const IdentifierInfo *getName() const {

      if (MacroDefinitionRecord *Def = getDefinition())

        return Def->getName();

      return NameOrDef.get<IdentifierInfo *>();

    }

    /// The definition of the macro being expanded. May return null if

    /// this is a builtin macro.

    MacroDefinitionRecord *getDefinition() const {

      return NameOrDef.dyn_cast<MacroDefinitionRecord *>();

    }

    // Implement isa/cast/dyncast/etc.

    static bool classof(const PreprocessedEntity *PE) {

      return PE->getKind() == MacroExpansionKind;

    }

  };

  /// Record the location of an inclusion directive, such as an

  /// \c \#include or \c \#import statement.

  class InclusionDirective : public PreprocessingDirective {

  public:

    /// The kind of inclusion directives known to the

    /// preprocessor.

    enum InclusionKind {

      /// An \c \#include directive.

      Include,

      /// An Objective-C \c \#import directive.

      Import,

      /// A GNU \c \#include_next directive.

      IncludeNext,

      /// A Clang \c \#__include_macros directive.

      IncludeMacros

    };

  private:

    /// The name of the file that was included, as written in

    /// the source.

    StringRef FileName;

    /// Whether the file name was in quotation marks; otherwise, it was

    /// in angle brackets.

    unsigned InQuotes : 1;

    /// The kind of inclusion directive we have.

    ///

    /// This is a value of type InclusionKind.

    unsigned Kind : 2;

    /// Whether the inclusion directive was automatically turned into

    /// a module import.

    unsigned ImportedModule : 1;

    /// The file that was included.

    OptionalFileEntryRef File;

  public:

    InclusionDirective(PreprocessingRecord &PPRec, InclusionKind Kind,

                       StringRef FileName, bool InQuotes, bool ImportedModule,

                       OptionalFileEntryRef File, SourceRange Range);

    /// Determine what kind of inclusion directive this is.

    InclusionKind getKind() const { return static_cast<InclusionKind>(Kind); }

    /// Retrieve the included file name as it was written in the source.

    StringRef getFileName() const { return FileName; }

    /// Determine whether the included file name was written in quotes;

    /// otherwise, it was written in angle brackets.

    bool wasInQuotes() const { return InQuotes; }

    /// Determine whether the inclusion directive was automatically

    /// turned into a module import.

    bool importedModule() const { return ImportedModule; }

    /// Retrieve the file entry for the actual file that was included

    /// by this directive.

    OptionalFileEntryRef getFile() const { return File; }

    // Implement isa/cast/dyncast/etc.

    static bool classof(const PreprocessedEntity *PE) {

      return PE->getKind() == InclusionDirectiveKind;

    }

  };

  /// An abstract class that should be subclassed by any external source

  /// of preprocessing record entries.

  class ExternalPreprocessingRecordSource {

  public:

    virtual ~ExternalPreprocessingRecordSource();

    /// Read a preallocated preprocessed entity from the external source.

    ///

    /// \returns null if an error occurred that prevented the preprocessed

    /// entity from being loaded.

    virtual PreprocessedEntity *ReadPreprocessedEntity(unsigned Index) = 0;

    /// Returns a pair of [Begin, End) indices of preallocated

    /// preprocessed entities that \p Range encompasses.

    virtual std::pair<unsigned, unsigned>

        findPreprocessedEntitiesInRange(SourceRange Range) = 0;

    /// Optionally returns true or false if the preallocated preprocessed

    /// entity with index \p Index came from file \p FID.

    virtual std::optional<bool> isPreprocessedEntityInFileID(unsigned Index,

                                                             FileID FID) {

      return std::nullopt;

    }

    /// Read a preallocated skipped range from the external source.

    virtual SourceRange ReadSkippedRange(unsigned Index) = 0;

  };

  /// A record of the steps taken while preprocessing a source file,

  /// including the various preprocessing directives processed, macros

  /// expanded, etc.

  class PreprocessingRecord : public PPCallbacks {

    SourceManager &SourceMgr;

    /// Allocator used to store preprocessing objects.

    llvm::BumpPtrAllocator BumpAlloc;

    /// The set of preprocessed entities in this record, in order they

    /// were seen.

    std::vector<PreprocessedEntity *> PreprocessedEntities;

    /// The set of preprocessed entities in this record that have been

    /// loaded from external sources.

    ///

    /// The entries in this vector are loaded lazily from the external source,

    /// and are referenced by the iterator using negative indices.

    std::vector<PreprocessedEntity *> LoadedPreprocessedEntities;

    /// The set of ranges that were skipped by the preprocessor,

    std::vector<SourceRange> SkippedRanges;

    bool SkippedRangesAllLoaded = true;

    /// Global (loaded or local) ID for a preprocessed entity.

    /// Negative values are used to indicate preprocessed entities

    /// loaded from the external source while non-negative values are used to

    /// indicate preprocessed entities introduced by the current preprocessor.

    /// Value -1 corresponds to element 0 in the loaded entities vector,

    /// value -2 corresponds to element 1 in the loaded entities vector, etc.

    /// Value 0 is an invalid value, the index to local entities is 1-based,

    /// value 1 corresponds to element 0 in the local entities vector,

    /// value 2 corresponds to element 1 in the local entities vector, etc.

    class PPEntityID {

      friend class PreprocessingRecord;

      int ID = 0;

      explicit PPEntityID(int ID) : ID(ID) {}

    public:

      PPEntityID() = default;

    };

    static PPEntityID getPPEntityID(unsigned Index, bool isLoaded) {

      return isLoaded ? PPEntityID(-int(Index)-1) : PPEntityID(Index+1);

    }

    /// Mapping from MacroInfo structures to their definitions.

    llvm::DenseMap<const MacroInfo *, MacroDefinitionRecord *> MacroDefinitions;

    /// External source of preprocessed entities.

    ExternalPreprocessingRecordSource *ExternalSource = nullptr;

    /// Retrieve the preprocessed entity at the given ID.

    PreprocessedEntity *getPreprocessedEntity(PPEntityID PPID);

    /// Retrieve the loaded preprocessed entity at the given index.

    PreprocessedEntity *getLoadedPreprocessedEntity(unsigned Index);

    /// Determine the number of preprocessed entities that were

    /// loaded (or can be loaded) from an external source.

    unsigned getNumLoadedPreprocessedEntities() const {

      return LoadedPreprocessedEntities.size();

    }

    /// Returns a pair of [Begin, End) indices of local preprocessed

    /// entities that \p Range encompasses.

    std::pair<unsigned, unsigned>

      findLocalPreprocessedEntitiesInRange(SourceRange Range) const;

    unsigned findBeginLocalPreprocessedEntity(SourceLocation Loc) const;

    unsigned findEndLocalPreprocessedEntity(SourceLocation Loc) const;

    /// Allocate space for a new set of loaded preprocessed entities.

    ///

    /// \returns The index into the set of loaded preprocessed entities, which

    /// corresponds to the first newly-allocated entity.

    unsigned allocateLoadedEntities(unsigned NumEntities);

    /// Allocate space for a new set of loaded preprocessed skipped

    /// ranges.

    ///

    /// \returns The index into the set of loaded preprocessed ranges, which

    /// corresponds to the first newly-allocated range.

    unsigned allocateSkippedRanges(unsigned NumRanges);

    /// Ensures that all external skipped ranges have been loaded.

    void ensureSkippedRangesLoaded();

    /// Register a new macro definition.

    void RegisterMacroDefinition(MacroInfo *Macro, MacroDefinitionRecord *Def);

  public:

    /// Construct a new preprocessing record.

    explicit PreprocessingRecord(SourceManager &SM);

    /// Allocate memory in the preprocessing record.

    void *Allocate(unsigned Size, unsigned Align = 8) {

      return BumpAlloc.Allocate(Size, Align);

    }

    /// Deallocate memory in the preprocessing record.

    void Deallocate(void *Ptr) {}

    size_t getTotalMemory() const;

    SourceManager &getSourceManager() const { return SourceMgr; }

    /// Iteration over the preprocessed entities.

    ///

    /// In a complete iteration, the iterator walks the range [-M, N),

    /// where negative values are used to indicate preprocessed entities

    /// loaded from the external source while non-negative values are used to

    /// indicate preprocessed entities introduced by the current preprocessor.

    /// However, to provide iteration in source order (for, e.g., chained

    /// precompiled headers), dereferencing the iterator flips the negative

    /// values (corresponding to loaded entities), so that position -M

    /// corresponds to element 0 in the loaded entities vector, position -M+1

    /// corresponds to element 1 in the loaded entities vector, etc. This

    /// gives us a reasonably efficient, source-order walk.

    ///

    /// We define this as a wrapping iterator around an int. The

    /// iterator_adaptor_base class forwards the iterator methods to basic

    /// integer arithmetic.

    class iterator : public llvm::iterator_adaptor_base<

                         iterator, int, std::random_access_iterator_tag,

                         PreprocessedEntity *, int, PreprocessedEntity *,

                         PreprocessedEntity *> {

      friend class PreprocessingRecord;

      PreprocessingRecord *Self;

      iterator(PreprocessingRecord *Self, int Position)

          : iterator::iterator_adaptor_base(Position), Self(Self) {}

    public:

      iterator() : iterator(nullptr, 0) {}

      PreprocessedEntity *operator*() const {

        bool isLoaded = this->I < 0;

        unsigned Index = isLoaded ?

            Self->LoadedPreprocessedEntities.size() + this->I : this->I;

        PPEntityID ID = Self->getPPEntityID(Index, isLoaded);

        return Self->getPreprocessedEntity(ID);

      }

      PreprocessedEntity *operator->() const { return **this; }

    };

    /// Begin iterator for all preprocessed entities.

    iterator begin() {

      return iterator(this, -(int)LoadedPreprocessedEntities.size());

    }

    /// End iterator for all preprocessed entities.

    iterator end() {

      return iterator(this, PreprocessedEntities.size());

    }

    /// Begin iterator for local, non-loaded, preprocessed entities.

    iterator local_begin() {

      return iterator(this, 0);

    }

    /// End iterator for local, non-loaded, preprocessed entities.

    iterator local_end() {

      return iterator(this, PreprocessedEntities.size());

    }

    /// iterator range for the given range of loaded

    /// preprocessed entities.

    llvm::iterator_range<iterator> getIteratorsForLoadedRange(unsigned start,

                                                              unsigned count) {

      unsigned end = start + count;

      assert(end <= LoadedPreprocessedEntities.size());

      return llvm::make_range(

          iterator(this, int(start) - LoadedPreprocessedEntities.size()),

          iterator(this, int(end) - LoadedPreprocessedEntities.size()));

    }

    /// Returns a range of preprocessed entities that source range \p R

    /// encompasses.

    ///

    /// \param R the range to look for preprocessed entities.

    llvm::iterator_range<iterator>

    getPreprocessedEntitiesInRange(SourceRange R);

    /// Returns true if the preprocessed entity that \p PPEI iterator

    /// points to is coming from the file \p FID.

    ///

    /// Can be used to avoid implicit deserializations of preallocated

    /// preprocessed entities if we only care about entities of a specific file

    /// and not from files \#included in the range given at

    /// \see getPreprocessedEntitiesInRange.

    bool isEntityInFileID(iterator PPEI, FileID FID);

    /// Add a new preprocessed entity to this record.

    PPEntityID addPreprocessedEntity(PreprocessedEntity *Entity);

    /// Set the external source for preprocessed entities.

    void SetExternalSource(ExternalPreprocessingRecordSource &Source);

    /// Retrieve the external source for preprocessed entities.

    ExternalPreprocessingRecordSource *getExternalSource() const {

      return ExternalSource;

    }

    /// Retrieve the macro definition that corresponds to the given

    /// \c MacroInfo.

    MacroDefinitionRecord *findMacroDefinition(const MacroInfo *MI);

    /// Retrieve all ranges that got skipped while preprocessing.

    const std::vector<SourceRange> &getSkippedRanges() {

      ensureSkippedRangesLoaded();

      return SkippedRanges;

    }

  private:

    friend class ASTReader;

    friend class ASTWriter;

    void MacroExpands(const Token &Id, const MacroDefinition &MD,

                      SourceRange Range, const MacroArgs *Args) override;

    void MacroDefined(const Token &Id, const MacroDirective *MD) override;

    void MacroUndefined(const Token &Id, const MacroDefinition &MD,

                        const MacroDirective *Undef) override;

    void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,

                            StringRef FileName, bool IsAngled,

                            CharSourceRange FilenameRange,

                            OptionalFileEntryRef File, StringRef SearchPath,

                            StringRef RelativePath, const Module *Imported,

                            SrcMgr::CharacteristicKind FileType) override;

    void Ifdef(SourceLocation Loc, const Token &MacroNameTok,

               const MacroDefinition &MD) override;

    void Ifndef(SourceLocation Loc, const Token &MacroNameTok,

                const MacroDefinition &MD) override;

    using PPCallbacks::Elifdef;

    using PPCallbacks::Elifndef;

    void Elifdef(SourceLocation Loc, const Token &MacroNameTok,

                 const MacroDefinition &MD) override;

    void Elifndef(SourceLocation Loc, const Token &MacroNameTok,

                  const MacroDefinition &MD) override;

    /// Hook called whenever the 'defined' operator is seen.

    void Defined(const Token &MacroNameTok, const MacroDefinition &MD,

                 SourceRange Range) override;

    void SourceRangeSkipped(SourceRange Range,

                            SourceLocation EndifLoc) override;

    void addMacroExpansion(const Token &Id, const MacroInfo *MI,

                           SourceRange Range);

    /// Cached result of the last \see getPreprocessedEntitiesInRange

    /// query.

    struct {

      SourceRange Range;

      std::pair<int, int> Result;

    } CachedRangeQuery;

    std::pair<int, int> getPreprocessedEntitiesInRangeSlow(SourceRange R);

  };

} // namespace clang

inline void *operator new(size_t bytes, clang::PreprocessingRecord &PR,

                          unsigned alignment) noexcept {

  return PR.Allocate(bytes, alignment);

}

inline void operator delete(void *ptr, clang::PreprocessingRecord &PR,

                            unsigned) noexcept {

  PR.Deallocate(ptr);

}

#endif // LLVM_CLANG_LEX_PREPROCESSINGRECORD_H