path: root/include/clang/Basic/SourceLocation.h

//===--- SourceLocation.h - Compact identifier for Source Files -*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief Defines the clang::SourceLocation class and associated facilities.
///
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_SOURCELOCATION_H
#define LLVM_CLANG_SOURCELOCATION_H

#include "clang/Basic/LLVM.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/PointerLikeTypeTraits.h"
#include <cassert>
#include <functional>
#include <string>
#include <utility>

namespace llvm {
  class MemoryBuffer;
  template <typename T> struct DenseMapInfo;
  template <typename T> struct isPodLike;
}

namespace clang {

class SourceManager;

/// \brief An opaque identifier used by SourceManager which refers to a
/// source file (MemoryBuffer) along with its \#include path and \#line data.
///
class FileID {
  /// \brief A mostly-opaque identifier, where 0 is "invalid", >0 is 
  /// this module, and <-1 is something loaded from another module.
  int ID;
public:
  FileID() : ID(0) {}

  bool isInvalid() const { return ID == 0; }

  bool operator==(const FileID &RHS) const { return ID == RHS.ID; }
  bool operator<(const FileID &RHS) const { return ID < RHS.ID; }
  bool operator<=(const FileID &RHS) const { return ID <= RHS.ID; }
  bool operator!=(const FileID &RHS) const { return !(*this == RHS); }
  bool operator>(const FileID &RHS) const { return RHS < *this; }
  bool operator>=(const FileID &RHS) const { return RHS <= *this; }

  static FileID getSentinel() { return get(-1); }
  unsigned getHashValue() const { return static_cast<unsigned>(ID); }

private:
  friend class SourceManager;
  friend class ASTWriter;
  friend class ASTReader;
  
  static FileID get(int V) {
    FileID F;
    F.ID = V;
    return F;
  }
  int getOpaqueValue() const { return ID; }
};


/// \brief Encodes a location in the source. The SourceManager can decode this
/// to get at the full include stack, line and column information.
///
/// Technically, a source location is simply an offset into the manager's view
/// of the input source, which is all input buffers (including macro
/// expansions) concatenated in an effectively arbitrary order. The manager
/// actually maintains two blocks of input buffers. One, starting at offset
/// 0 and growing upwards, contains all buffers from this module. The other,
/// starting at the highest possible offset and growing downwards, contains
/// buffers of loaded modules.
///
/// In addition, one bit of SourceLocation is used for quick access to the
/// information whether the location is in a file or a macro expansion.
///
/// It is important that this type remains small. It is currently 32 bits wide.
class SourceLocation {
  unsigned ID;
  friend class SourceManager;
  friend class ASTReader;
  friend class ASTWriter;
  enum {
    MacroIDBit = 1U << 31
  };
public:

  SourceLocation() : ID(0) {}

  bool isFileID() const  { return (ID & MacroIDBit) == 0; }
  bool isMacroID() const { return (ID & MacroIDBit) != 0; }

  /// \brief Return true if this is a valid SourceLocation object.
  ///
  /// Invalid SourceLocations are often used when events have no corresponding
  /// location in the source (e.g. a diagnostic is required for a command line
  /// option).
  bool isValid() const { return ID != 0; }
  bool isInvalid() const { return ID == 0; }

private:
  /// \brief Return the offset into the manager's global input view.
  unsigned getOffset() const {
    return ID & ~MacroIDBit;
  }

  static SourceLocation getFileLoc(unsigned ID) {
    assert((ID & MacroIDBit) == 0 && "Ran out of source locations!");
    SourceLocation L;
    L.ID = ID;
    return L;
  }

  static SourceLocation getMacroLoc(unsigned ID) {
    assert((ID & MacroIDBit) == 0 && "Ran out of source locations!");
    SourceLocation L;
    L.ID = MacroIDBit | ID;
    return L;
  }
public:

  /// \brief Return a source location with the specified offset from this
  /// SourceLocation.
  SourceLocation getLocWithOffset(int Offset) const {
    assert(((getOffset()+Offset) & MacroIDBit) == 0 && "offset overflow");
    SourceLocation L;
    L.ID = ID+Offset;
    return L;
  }

  /// \brief When a SourceLocation itself cannot be used, this returns
  /// an (opaque) 32-bit integer encoding for it.
  ///
  /// This should only be passed to SourceLocation::getFromRawEncoding, it
  /// should not be inspected directly.
  unsigned getRawEncoding() const { return ID; }

  /// \brief Turn a raw encoding of a SourceLocation object into
  /// a real SourceLocation.
  ///
  /// \see getRawEncoding.
  static SourceLocation getFromRawEncoding(unsigned Encoding) {
    SourceLocation X;
    X.ID = Encoding;
    return X;
  }

  /// \brief When a SourceLocation itself cannot be used, this returns
  /// an (opaque) pointer encoding for it.
  ///
  /// This should only be passed to SourceLocation::getFromPtrEncoding, it
  /// should not be inspected directly.
  void* getPtrEncoding() const {
    // Double cast to avoid a warning "cast to pointer from integer of different
    // size".
    return (void*)(uintptr_t)getRawEncoding();
  }

  /// \brief Turn a pointer encoding of a SourceLocation object back
  /// into a real SourceLocation.
  static SourceLocation getFromPtrEncoding(const void *Encoding) {
    return getFromRawEncoding((unsigned)(uintptr_t)Encoding);
  }

  void print(raw_ostream &OS, const SourceManager &SM) const;
  LLVM_ATTRIBUTE_USED std::string printToString(const SourceManager &SM) const;
  void dump(const SourceManager &SM) const;
};

inline bool operator==(const SourceLocation &LHS, const SourceLocation &RHS) {
  return LHS.getRawEncoding() == RHS.getRawEncoding();
}

inline bool operator!=(const SourceLocation &LHS, const SourceLocation &RHS) {
  return !(LHS == RHS);
}

inline bool operator<(const SourceLocation &LHS, const SourceLocation &RHS) {
  return LHS.getRawEncoding() < RHS.getRawEncoding();
}

/// \brief A trival tuple used to represent a source range.
class SourceRange {
  SourceLocation B;
  SourceLocation E;
public:
  SourceRange(): B(SourceLocation()), E(SourceLocation()) {}
  SourceRange(SourceLocation loc) : B(loc), E(loc) {}
  SourceRange(SourceLocation begin, SourceLocation end) : B(begin), E(end) {}

  SourceLocation getBegin() const { return B; }
  SourceLocation getEnd() const { return E; }

  void setBegin(SourceLocation b) { B = b; }
  void setEnd(SourceLocation e) { E = e; }

  bool isValid() const { return B.isValid() && E.isValid(); }
  bool isInvalid() const { return !isValid(); }

  bool operator==(const SourceRange &X) const {
    return B == X.B && E == X.E;
  }

  bool operator!=(const SourceRange &X) const {
    return B != X.B || E != X.E;
  }
};
  
/// \brief Represents a character-granular source range.
///
/// The underlying SourceRange can either specify the starting/ending character
/// of the range, or it can specify the start of the range and the start of the
/// last token of the range (a "token range").  In the token range case, the
/// size of the last token must be measured to determine the actual end of the
/// range.
class CharSourceRange { 
  SourceRange Range;
  bool IsTokenRange;
public:
  CharSourceRange() : IsTokenRange(false) {}
  CharSourceRange(SourceRange R, bool ITR) : Range(R), IsTokenRange(ITR) {}

  static CharSourceRange getTokenRange(SourceRange R) {
    return CharSourceRange(R, true);
  }

  static CharSourceRange getCharRange(SourceRange R) {
    return CharSourceRange(R, false);