//===- ModuleFile.h - Module file description -------------------*- 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 Module class, which describes a module that has
 
//  been loaded from an AST file.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_SERIALIZATION_MODULEFILE_H
 
#define LLVM_CLANG_SERIALIZATION_MODULEFILE_H
 
 
 
#include "clang/Basic/FileManager.h"
 
#include "clang/Basic/Module.h"
 
#include "clang/Basic/SourceLocation.h"
 
#include "clang/Serialization/ASTBitCodes.h"
 
#include "clang/Serialization/ContinuousRangeMap.h"
 
#include "clang/Serialization/ModuleFileExtension.h"
 
#include "llvm/ADT/BitVector.h"
 
#include "llvm/ADT/DenseMap.h"
 
#include "llvm/ADT/PointerIntPair.h"
 
#include "llvm/ADT/SetVector.h"
 
#include "llvm/ADT/SmallVector.h"
 
#include "llvm/ADT/StringRef.h"
 
#include "llvm/Bitstream/BitstreamReader.h"
 
#include "llvm/Support/Endian.h"
 
#include <cassert>
 
#include <cstdint>
 
#include <memory>
 
#include <string>
 
#include <vector>
 
 
 
namespace clang {
 
 
 
namespace serialization {
 
 
 
/// Specifies the kind of module that has been loaded.
 
enum ModuleKind {
 
  /// File is an implicitly-loaded module.
 
  MK_ImplicitModule,
 
 
 
  /// File is an explicitly-loaded module.
 
  MK_ExplicitModule,
 
 
 
  /// File is a PCH file treated as such.
 
  MK_PCH,
 
 
 
  /// File is a PCH file treated as the preamble.
 
  MK_Preamble,
 
 
 
  /// File is a PCH file treated as the actual main file.
 
  MK_MainFile,
 
 
 
  /// File is from a prebuilt module path.
 
  MK_PrebuiltModule
 
};
 
 
 
/// The input file info that has been loaded from an AST file.
 
struct InputFileInfo {
 
  std::string Filename;
 
  uint64_t ContentHash;
 
  off_t StoredSize;
 
  time_t StoredTime;
 
  bool Overridden;
 
  bool Transient;
 
  bool TopLevelModuleMap;
 
};
 
 
 
/// The input file that has been loaded from this AST file, along with
 
/// bools indicating whether this was an overridden buffer or if it was
 
/// out-of-date or not-found.
 
class InputFile {
 
  enum {
 
    Overridden = 1,
 
    OutOfDate = 2,
 
    NotFound = 3
 
  };
 
  llvm::PointerIntPair<const FileEntryRef::MapEntry *, 2, unsigned> Val;
 
 
 
public:
 
  InputFile() = default;
 
 
 
  InputFile(FileEntryRef File, bool isOverridden = false,
 
            bool isOutOfDate = false) {
 
    assert(!(isOverridden && isOutOfDate) &&
 
           "an overridden cannot be out-of-date");
 
    unsigned intVal = 0;
 
    if (isOverridden)
 
      intVal = Overridden;
 
    else if (isOutOfDate)
 
      intVal = OutOfDate;
 
    Val.setPointerAndInt(&File.getMapEntry(), intVal);
 
  }
 
 
 
  static InputFile getNotFound() {
 
    InputFile File;
 
    File.Val.setInt(NotFound);
 
    return File;
 
  }
 
 
 
  OptionalFileEntryRefDegradesToFileEntryPtr getFile() const {
 
    if (auto *P = Val.getPointer())
 
      return FileEntryRef(*P);
 
    return std::nullopt;
 
  }
 
  bool isOverridden() const { return Val.getInt() == Overridden; }
 
  bool isOutOfDate() const { return Val.getInt() == OutOfDate; }
 
  bool isNotFound() const { return Val.getInt() == NotFound; }
 
};
 
 
 
/// Information about a module that has been loaded by the ASTReader.
 
///
 
/// Each instance of the Module class corresponds to a single AST file, which
 
/// may be a precompiled header, precompiled preamble, a module, or an AST file
 
/// of some sort loaded as the main file, all of which are specific formulations
 
/// of the general notion of a "module". A module may depend on any number of
 
/// other modules.
 
class ModuleFile {
 
public:
 
  ModuleFile(ModuleKind Kind, unsigned Generation)
 
      : Kind(Kind), Generation(Generation) {}
 
  ~ModuleFile();
 
 
 
  // === General information ===
 
 
 
  /// The index of this module in the list of modules.
 
  unsigned Index = 0;
 
 
 
  /// The type of this module.
 
  ModuleKind Kind;
 
 
 
  /// The file name of the module file.
 
  std::string FileName;
 
 
 
  /// The name of the module.
 
  std::string ModuleName;
 
 
 
  /// The base directory of the module.
 
  std::string BaseDirectory;
 
 
 
  std::string getTimestampFilename() const {
 
    return FileName + ".timestamp";
 
  }
 
 
 
  /// The original source file name that was used to build the
 
  /// primary AST file, which may have been modified for
 
  /// relocatable-pch support.
 
  std::string OriginalSourceFileName;
 
 
 
  /// The actual original source file name that was used to
 
  /// build this AST file.
 
  std::string ActualOriginalSourceFileName;
 
 
 
  /// The file ID for the original source file that was used to
 
  /// build this AST file.
 
  FileID OriginalSourceFileID;
 
 
 
  std::string ModuleMapPath;
 
 
 
  /// Whether this precompiled header is a relocatable PCH file.
 
  bool RelocatablePCH = false;
 
 
 
  /// Whether timestamps are included in this module file.
 
  bool HasTimestamps = false;
 
 
 
  /// Whether the top-level module has been read from the AST file.
 
  bool DidReadTopLevelSubmodule = false;
 
 
 
  /// The file entry for the module file.
 
  OptionalFileEntryRefDegradesToFileEntryPtr File;
 
 
 
  /// The signature of the module file, which may be used instead of the size
 
  /// and modification time to identify this particular file.
 
  ASTFileSignature Signature;
 
 
 
  /// The signature of the AST block of the module file, this can be used to
 
  /// unique module files based on AST contents.
 
  ASTFileSignature ASTBlockHash;
 
 
 
  /// The bit vector denoting usage of each header search entry (true = used).
 
  llvm::BitVector SearchPathUsage;
 
 
 
  /// Whether this module has been directly imported by the
 
  /// user.
 
  bool DirectlyImported = false;
 
 
 
  /// The generation of which this module file is a part.
 
  unsigned Generation;
 
 
 
  /// The memory buffer that stores the data associated with
 
  /// this AST file, owned by the InMemoryModuleCache.
 
  llvm::MemoryBuffer *Buffer;
 
 
 
  /// The size of this file, in bits.
 
  uint64_t SizeInBits = 0;
 
 
 
  /// The global bit offset (or base) of this module
 
  uint64_t GlobalBitOffset = 0;
 
 
 
  /// The bit offset of the AST block of this module.
 
  uint64_t ASTBlockStartOffset = 0;
 
 
 
  /// The serialized bitstream data for this file.
 
  StringRef Data;
 
 
 
  /// The main bitstream cursor for the main block.
 
  llvm::BitstreamCursor Stream;
 
 
 
  /// The source location where the module was explicitly or implicitly
 
  /// imported in the local translation unit.
 
  ///
 
  /// If module A depends on and imports module B, both modules will have the
 
  /// same DirectImportLoc, but different ImportLoc (B's ImportLoc will be a
 
  /// source location inside module A).
 
  ///
 
  /// WARNING: This is largely useless. It doesn't tell you when a module was
 
  /// made visible, just when the first submodule of that module was imported.
 
  SourceLocation DirectImportLoc;
 
 
 
  /// The source location where this module was first imported.
 
  SourceLocation ImportLoc;
 
 
 
  /// The first source location in this module.
 
  SourceLocation FirstLoc;
 
 
 
  /// The list of extension readers that are attached to this module
 
  /// file.
 
  std::vector<std::unique_ptr<ModuleFileExtensionReader>> ExtensionReaders;
 
 
 
  /// The module offset map data for this file. If non-empty, the various
 
  /// ContinuousRangeMaps described below have not yet been populated.
 
  StringRef ModuleOffsetMap;
 
 
 
  // === Input Files ===
 
 
 
  /// The cursor to the start of the input-files block.
 
  llvm::BitstreamCursor InputFilesCursor;
 
 
 
  /// Offsets for all of the input file entries in the AST file.
 
  const llvm::support::unaligned_uint64_t *InputFileOffsets = nullptr;
 
 
 
  /// The input files that have been loaded from this AST file.
 
  std::vector<InputFile> InputFilesLoaded;
 
 
 
  /// The input file infos that have been loaded from this AST file.
 
  std::vector<InputFileInfo> InputFileInfosLoaded;
 
 
 
  // All user input files reside at the index range [0, NumUserInputFiles), and
 
  // system input files reside at [NumUserInputFiles, InputFilesLoaded.size()).
 
  unsigned NumUserInputFiles = 0;
 
 
 
  /// If non-zero, specifies the time when we last validated input
 
  /// files.  Zero means we never validated them.
 
  ///
 
  /// The time is specified in seconds since the start of the Epoch.
 
  uint64_t InputFilesValidationTimestamp = 0;
 
 
 
  // === Source Locations ===
 
 
 
  /// Cursor used to read source location entries.
 
  llvm::BitstreamCursor SLocEntryCursor;
 
 
 
  /// The bit offset to the start of the SOURCE_MANAGER_BLOCK.
 
  uint64_t SourceManagerBlockStartOffset = 0;
 
 
 
  /// The number of source location entries in this AST file.
 
  unsigned LocalNumSLocEntries = 0;
 
 
 
  /// The base ID in the source manager's view of this module.
 
  int SLocEntryBaseID = 0;
 
 
 
  /// The base offset in the source manager's view of this module.
 
  SourceLocation::UIntTy SLocEntryBaseOffset = 0;
 
 
 
  /// Base file offset for the offsets in SLocEntryOffsets. Real file offset
 
  /// for the entry is SLocEntryOffsetsBase + SLocEntryOffsets[i].
 
  uint64_t SLocEntryOffsetsBase = 0;
 
 
 
  /// Offsets for all of the source location entries in the
 
  /// AST file.
 
  const uint32_t *SLocEntryOffsets = nullptr;
 
 
 
  /// SLocEntries that we're going to preload.
 
  SmallVector<uint64_t, 4> PreloadSLocEntries;
 
 
 
  /// Remapping table for source locations in this module.
 
  ContinuousRangeMap<SourceLocation::UIntTy, SourceLocation::IntTy, 2>
 
      SLocRemap;
 
 
 
  // === Identifiers ===
 
 
 
  /// The number of identifiers in this AST file.
 
  unsigned LocalNumIdentifiers = 0;
 
 
 
  /// Offsets into the identifier table data.
 
  ///
 
  /// This array is indexed by the identifier ID (-1), and provides
 
  /// the offset into IdentifierTableData where the string data is
 
  /// stored.
 
  const uint32_t *IdentifierOffsets = nullptr;
 
 
 
  /// Base identifier ID for identifiers local to this module.
 
  serialization::IdentID BaseIdentifierID = 0;
 
 
 
  /// Remapping table for identifier IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> IdentifierRemap;
 
 
 
  /// Actual data for the on-disk hash table of identifiers.
 
  ///
 
  /// This pointer points into a memory buffer, where the on-disk hash
 
  /// table for identifiers actually lives.
 
  const unsigned char *IdentifierTableData = nullptr;
 
 
 
  /// A pointer to an on-disk hash table of opaque type
 
  /// IdentifierHashTable.
 
  void *IdentifierLookupTable = nullptr;
 
 
 
  /// Offsets of identifiers that we're going to preload within
 
  /// IdentifierTableData.
 
  std::vector<unsigned> PreloadIdentifierOffsets;
 
 
 
  // === Macros ===
 
 
 
  /// The cursor to the start of the preprocessor block, which stores
 
  /// all of the macro definitions.
 
  llvm::BitstreamCursor MacroCursor;
 
 
 
  /// The number of macros in this AST file.
 
  unsigned LocalNumMacros = 0;
 
 
 
  /// Base file offset for the offsets in MacroOffsets. Real file offset for
 
  /// the entry is MacroOffsetsBase + MacroOffsets[i].
 
  uint64_t MacroOffsetsBase = 0;
 
 
 
  /// Offsets of macros in the preprocessor block.
 
  ///
 
  /// This array is indexed by the macro ID (-1), and provides
 
  /// the offset into the preprocessor block where macro definitions are
 
  /// stored.
 
  const uint32_t *MacroOffsets = nullptr;
 
 
 
  /// Base macro ID for macros local to this module.
 
  serialization::MacroID BaseMacroID = 0;
 
 
 
  /// Remapping table for macro IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> MacroRemap;
 
 
 
  /// The offset of the start of the set of defined macros.
 
  uint64_t MacroStartOffset = 0;
 
 
 
  // === Detailed PreprocessingRecord ===
 
 
 
  /// The cursor to the start of the (optional) detailed preprocessing
 
  /// record block.
 
  llvm::BitstreamCursor PreprocessorDetailCursor;
 
 
 
  /// The offset of the start of the preprocessor detail cursor.
 
  uint64_t PreprocessorDetailStartOffset = 0;
 
 
 
  /// Base preprocessed entity ID for preprocessed entities local to
 
  /// this module.
 
  serialization::PreprocessedEntityID BasePreprocessedEntityID = 0;
 
 
 
  /// Remapping table for preprocessed entity IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> PreprocessedEntityRemap;
 
 
 
  const PPEntityOffset *PreprocessedEntityOffsets = nullptr;
 
  unsigned NumPreprocessedEntities = 0;
 
 
 
  /// Base ID for preprocessed skipped ranges local to this module.
 
  unsigned BasePreprocessedSkippedRangeID = 0;
 
 
 
  const PPSkippedRange *PreprocessedSkippedRangeOffsets = nullptr;
 
  unsigned NumPreprocessedSkippedRanges = 0;
 
 
 
  // === Header search information ===
 
 
 
  /// The number of local HeaderFileInfo structures.
 
  unsigned LocalNumHeaderFileInfos = 0;
 
 
 
  /// Actual data for the on-disk hash table of header file
 
  /// information.
 
  ///
 
  /// This pointer points into a memory buffer, where the on-disk hash
 
  /// table for header file information actually lives.
 
  const char *HeaderFileInfoTableData = nullptr;
 
 
 
  /// The on-disk hash table that contains information about each of
 
  /// the header files.
 
  void *HeaderFileInfoTable = nullptr;
 
 
 
  // === Submodule information ===
 
 
 
  /// The number of submodules in this module.
 
  unsigned LocalNumSubmodules = 0;
 
 
 
  /// Base submodule ID for submodules local to this module.
 
  serialization::SubmoduleID BaseSubmoduleID = 0;
 
 
 
  /// Remapping table for submodule IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> SubmoduleRemap;
 
 
 
  // === Selectors ===
 
 
 
  /// The number of selectors new to this file.
 
  ///
 
  /// This is the number of entries in SelectorOffsets.
 
  unsigned LocalNumSelectors = 0;
 
 
 
  /// Offsets into the selector lookup table's data array
 
  /// where each selector resides.
 
  const uint32_t *SelectorOffsets = nullptr;
 
 
 
  /// Base selector ID for selectors local to this module.
 
  serialization::SelectorID BaseSelectorID = 0;
 
 
 
  /// Remapping table for selector IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> SelectorRemap;
 
 
 
  /// A pointer to the character data that comprises the selector table
 
  ///
 
  /// The SelectorOffsets table refers into this memory.
 
  const unsigned char *SelectorLookupTableData = nullptr;
 
 
 
  /// A pointer to an on-disk hash table of opaque type
 
  /// ASTSelectorLookupTable.
 
  ///
 
  /// This hash table provides the IDs of all selectors, and the associated
 
  /// instance and factory methods.
 
  void *SelectorLookupTable = nullptr;
 
 
 
  // === Declarations ===
 
 
 
  /// DeclsCursor - This is a cursor to the start of the DECLTYPES_BLOCK block.
 
  /// It has read all the abbreviations at the start of the block and is ready
 
  /// to jump around with these in context.
 
  llvm::BitstreamCursor DeclsCursor;
 
 
 
  /// The offset to the start of the DECLTYPES_BLOCK block.
 
  uint64_t DeclsBlockStartOffset = 0;
 
 
 
  /// The number of declarations in this AST file.
 
  unsigned LocalNumDecls = 0;
 
 
 
  /// Offset of each declaration within the bitstream, indexed
 
  /// by the declaration ID (-1).
 
  const DeclOffset *DeclOffsets = nullptr;
 
 
 
  /// Base declaration ID for declarations local to this module.
 
  serialization::DeclID BaseDeclID = 0;
 
 
 
  /// Remapping table for declaration IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> DeclRemap;
 
 
 
  /// Mapping from the module files that this module file depends on
 
  /// to the base declaration ID for that module as it is understood within this
 
  /// module.
 
  ///
 
  /// This is effectively a reverse global-to-local mapping for declaration
 
  /// IDs, so that we can interpret a true global ID (for this translation unit)
 
  /// as a local ID (for this module file).
 
  llvm::DenseMap<ModuleFile *, serialization::DeclID> GlobalToLocalDeclIDs;
 
 
 
  /// Array of file-level DeclIDs sorted by file.
 
  const serialization::DeclID *FileSortedDecls = nullptr;
 
  unsigned NumFileSortedDecls = 0;
 
 
 
  /// Array of category list location information within this
 
  /// module file, sorted by the definition ID.
 
  const serialization::ObjCCategoriesInfo *ObjCCategoriesMap = nullptr;
 
 
 
  /// The number of redeclaration info entries in ObjCCategoriesMap.
 
  unsigned LocalNumObjCCategoriesInMap = 0;
 
 
 
  /// The Objective-C category lists for categories known to this
 
  /// module.
 
  SmallVector<uint64_t, 1> ObjCCategories;
 
 
 
  // === Types ===
 
 
 
  /// The number of types in this AST file.
 
  unsigned LocalNumTypes = 0;
 
 
 
  /// Offset of each type within the bitstream, indexed by the
 
  /// type ID, or the representation of a Type*.
 
  const UnderalignedInt64 *TypeOffsets = nullptr;
 
 
 
  /// Base type ID for types local to this module as represented in
 
  /// the global type ID space.
 
  serialization::TypeID BaseTypeIndex = 0;
 
 
 
  /// Remapping table for type IDs in this module.
 
  ContinuousRangeMap<uint32_t, int, 2> TypeRemap;
 
 
 
  // === Miscellaneous ===
 
 
 
  /// Diagnostic IDs and their mappings that the user changed.
 
  SmallVector<uint64_t, 8> PragmaDiagMappings;
 
 
 
  /// List of modules which depend on this module
 
  llvm::SetVector<ModuleFile *> ImportedBy;
 
 
 
  /// List of modules which this module depends on
 
  llvm::SetVector<ModuleFile *> Imports;
 
 
 
  /// Determine whether this module was directly imported at
 
  /// any point during translation.
 
  bool isDirectlyImported() const { return DirectlyImported; }
 
 
 
  /// Is this a module file for a module (rather than a PCH or similar).
 
  bool isModule() const {
 
    return Kind == MK_ImplicitModule || Kind == MK_ExplicitModule ||
 
           Kind == MK_PrebuiltModule;
 
  }
 
 
 
  /// Dump debugging output for this module.
 
  void dump();
 
};
 
 
 
} // namespace serialization
 
 
 
} // namespace clang
 
 
 
#endif // LLVM_CLANG_SERIALIZATION_MODULEFILE_H