1//===--- SourceLocation.h - Compact identifier for Source Files -*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9///
10/// \file
11/// \brief Defines the clang::SourceLocation class and associated facilities.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_BASIC_SOURCELOCATION_H
16#define LLVM_CLANG_BASIC_SOURCELOCATION_H
17
18#include "clang/Basic/LLVM.h"
19#include "llvm/Support/Compiler.h"
20#include "llvm/Support/PointerLikeTypeTraits.h"
21#include <cassert>
22#include <functional>
23#include <string>
24#include <utility>
25
26namespace llvm {
27  class MemoryBuffer;
28  template <typename T> struct DenseMapInfo;
29  template <typename T> struct isPodLike;
30}
31
32namespace clang {
33
34class SourceManager;
35
36/// \brief An opaque identifier used by SourceManager which refers to a
37/// source file (MemoryBuffer) along with its \#include path and \#line data.
38///
39class FileID {
40  /// \brief A mostly-opaque identifier, where 0 is "invalid", >0 is
41  /// this module, and <-1 is something loaded from another module.
42  int ID;
43public:
44  FileID() : ID(0) {}
45
46  bool isValid() const { return ID != 0; }
47  bool isInvalid() const { return ID == 0; }
48
49  bool operator==(const FileID &RHS) const { return ID == RHS.ID; }
50  bool operator<(const FileID &RHS) const { return ID < RHS.ID; }
51  bool operator<=(const FileID &RHS) const { return ID <= RHS.ID; }
52  bool operator!=(const FileID &RHS) const { return !(*this == RHS); }
53  bool operator>(const FileID &RHS) const { return RHS < *this; }
54  bool operator>=(const FileID &RHS) const { return RHS <= *this; }
55
56  static FileID getSentinel() { return get(-1); }
57  unsigned getHashValue() const { return static_cast<unsigned>(ID); }
58
59private:
60  friend class SourceManager;
61  friend class ASTWriter;
62  friend class ASTReader;
63
64  static FileID get(int V) {
65    FileID F;
66    F.ID = V;
67    return F;
68  }
69  int getOpaqueValue() const { return ID; }
70};
71
72
73/// \brief Encodes a location in the source. The SourceManager can decode this
74/// to get at the full include stack, line and column information.
75///
76/// Technically, a source location is simply an offset into the manager's view
77/// of the input source, which is all input buffers (including macro
78/// expansions) concatenated in an effectively arbitrary order. The manager
79/// actually maintains two blocks of input buffers. One, starting at offset
80/// 0 and growing upwards, contains all buffers from this module. The other,
81/// starting at the highest possible offset and growing downwards, contains
82/// buffers of loaded modules.
83///
84/// In addition, one bit of SourceLocation is used for quick access to the
85/// information whether the location is in a file or a macro expansion.
86///
87/// It is important that this type remains small. It is currently 32 bits wide.
88class SourceLocation {
89  unsigned ID;
90  friend class SourceManager;
91  friend class ASTReader;
92  friend class ASTWriter;
93  enum : unsigned {
94    MacroIDBit = 1U << 31
95  };
96public:
97
98  SourceLocation() : ID(0) {}
99
100  bool isFileID() const  { return (ID & MacroIDBit) == 0; }
101  bool isMacroID() const { return (ID & MacroIDBit) != 0; }
102
103  /// \brief Return true if this is a valid SourceLocation object.
104  ///
105  /// Invalid SourceLocations are often used when events have no corresponding
106  /// location in the source (e.g. a diagnostic is required for a command line
107  /// option).
108  bool isValid() const { return ID != 0; }
109  bool isInvalid() const { return ID == 0; }
110
111private:
112  /// \brief Return the offset into the manager's global input view.
113  unsigned getOffset() const {
114    return ID & ~MacroIDBit;
115  }
116
117  static SourceLocation getFileLoc(unsigned ID) {
118    assert((ID & MacroIDBit) == 0 && "Ran out of source locations!");
119    SourceLocation L;
120    L.ID = ID;
121    return L;
122  }
123
124  static SourceLocation getMacroLoc(unsigned ID) {
125    assert((ID & MacroIDBit) == 0 && "Ran out of source locations!");
126    SourceLocation L;
127    L.ID = MacroIDBit | ID;
128    return L;
129  }
130public:
131
132  /// \brief Return a source location with the specified offset from this
133  /// SourceLocation.
134  SourceLocation getLocWithOffset(int Offset) const {
135    assert(((getOffset()+Offset) & MacroIDBit) == 0 && "offset overflow");
136    SourceLocation L;
137    L.ID = ID+Offset;
138    return L;
139  }
140
141  /// \brief When a SourceLocation itself cannot be used, this returns
142  /// an (opaque) 32-bit integer encoding for it.
143  ///
144  /// This should only be passed to SourceLocation::getFromRawEncoding, it
145  /// should not be inspected directly.
146  unsigned getRawEncoding() const { return ID; }
147
148  /// \brief Turn a raw encoding of a SourceLocation object into
149  /// a real SourceLocation.
150  ///
151  /// \see getRawEncoding.
152  static SourceLocation getFromRawEncoding(unsigned Encoding) {
153    SourceLocation X;
154    X.ID = Encoding;
155    return X;
156  }
157
158  /// \brief When a SourceLocation itself cannot be used, this returns
159  /// an (opaque) pointer encoding for it.
160  ///
161  /// This should only be passed to SourceLocation::getFromPtrEncoding, it
162  /// should not be inspected directly.
163  void* getPtrEncoding() const {
164    // Double cast to avoid a warning "cast to pointer from integer of different
165    // size".
166    return (void*)(uintptr_t)getRawEncoding();
167  }
168
169  /// \brief Turn a pointer encoding of a SourceLocation object back
170  /// into a real SourceLocation.
171  static SourceLocation getFromPtrEncoding(const void *Encoding) {
172    return getFromRawEncoding((unsigned)(uintptr_t)Encoding);
173  }
174
175  void print(raw_ostream &OS, const SourceManager &SM) const;
176  std::string printToString(const SourceManager &SM) const;
177  void dump(const SourceManager &SM) const;
178};
179
180inline bool operator==(const SourceLocation &LHS, const SourceLocation &RHS) {
181  return LHS.getRawEncoding() == RHS.getRawEncoding();
182}
183
184inline bool operator!=(const SourceLocation &LHS, const SourceLocation &RHS) {
185  return !(LHS == RHS);
186}
187
188inline bool operator<(const SourceLocation &LHS, const SourceLocation &RHS) {
189  return LHS.getRawEncoding() < RHS.getRawEncoding();
190}
191
192/// \brief A trivial tuple used to represent a source range.
193class SourceRange {
194  SourceLocation B;
195  SourceLocation E;
196public:
197  SourceRange(): B(SourceLocation()), E(SourceLocation()) {}
198  SourceRange(SourceLocation loc) : B(loc), E(loc) {}
199  SourceRange(SourceLocation begin, SourceLocation end) : B(begin), E(end) {}
200
201  SourceLocation getBegin() const { return B; }
202  SourceLocation getEnd() const { return E; }
203
204  void setBegin(SourceLocation b) { B = b; }
205  void setEnd(SourceLocation e) { E = e; }
206
207  bool isValid() const { return B.isValid() && E.isValid(); }
208  bool isInvalid() const { return !isValid(); }
209
210  bool operator==(const SourceRange &X) const {
211    return B == X.B && E == X.E;
212  }
213
214  bool operator!=(const SourceRange &X) const {
215    return B != X.B || E != X.E;
216  }
217};
218
219/// \brief Represents a character-granular source range.
220///
221/// The underlying SourceRange can either specify the starting/ending character
222/// of the range, or it can specify the start of the range and the start of the
223/// last token of the range (a "token range").  In the token range case, the
224/// size of the last token must be measured to determine the actual end of the
225/// range.
226class CharSourceRange {
227  SourceRange Range;
228  bool IsTokenRange;
229public:
230  CharSourceRange() : IsTokenRange(false) {}
231  CharSourceRange(SourceRange R, bool ITR) : Range(R), IsTokenRange(ITR) {}
232
233  static CharSourceRange getTokenRange(SourceRange R) {
234    return CharSourceRange(R, true);
235  }
236
237  static CharSourceRange getCharRange(SourceRange R) {
238    return CharSourceRange(R, false);
239  }
240
241  static CharSourceRange getTokenRange(SourceLocation B, SourceLocation E) {
242    return getTokenRange(SourceRange(B, E));
243  }
244  static CharSourceRange getCharRange(SourceLocation B, SourceLocation E) {
245    return getCharRange(SourceRange(B, E));
246  }
247
248  /// \brief Return true if the end of this range specifies the start of
249  /// the last token.  Return false if the end of this range specifies the last
250  /// character in the range.
251  bool isTokenRange() const { return IsTokenRange; }
252  bool isCharRange() const { return !IsTokenRange; }
253
254  SourceLocation getBegin() const { return Range.getBegin(); }
255  SourceLocation getEnd() const { return Range.getEnd(); }
256  SourceRange getAsRange() const { return Range; }
257
258  void setBegin(SourceLocation b) { Range.setBegin(b); }
259  void setEnd(SourceLocation e) { Range.setEnd(e); }
260
261  bool isValid() const { return Range.isValid(); }
262  bool isInvalid() const { return !isValid(); }
263};
264
265/// \brief A SourceLocation and its associated SourceManager.
266///
267/// This is useful for argument passing to functions that expect both objects.
268class FullSourceLoc : public SourceLocation {
269  const SourceManager *SrcMgr;
270public:
271  /// \brief Creates a FullSourceLoc where isValid() returns \c false.
272  explicit FullSourceLoc() : SrcMgr(nullptr) {}
273
274  explicit FullSourceLoc(SourceLocation Loc, const SourceManager &SM)
275    : SourceLocation(Loc), SrcMgr(&SM) {}
276
277  /// \pre This FullSourceLoc has an associated SourceManager.
278  const SourceManager &getManager() const {
279    assert(SrcMgr && "SourceManager is NULL.");
280    return *SrcMgr;
281  }
282
283  FileID getFileID() const;
284
285  FullSourceLoc getExpansionLoc() const;
286  FullSourceLoc getSpellingLoc() const;
287
288  unsigned getExpansionLineNumber(bool *Invalid = nullptr) const;
289  unsigned getExpansionColumnNumber(bool *Invalid = nullptr) const;
290
291  unsigned getSpellingLineNumber(bool *Invalid = nullptr) const;
292  unsigned getSpellingColumnNumber(bool *Invalid = nullptr) const;
293
294  const char *getCharacterData(bool *Invalid = nullptr) const;
295
296
297  /// \brief Return a StringRef to the source buffer data for the
298  /// specified FileID.
299  StringRef getBufferData(bool *Invalid = nullptr) const;
300
301  /// \brief Decompose the specified location into a raw FileID + Offset pair.
302  ///
303  /// The first element is the FileID, the second is the offset from the
304  /// start of the buffer of the location.
305  std::pair<FileID, unsigned> getDecomposedLoc() const;
306
307  bool isInSystemHeader() const;
308
309  /// \brief Determines the order of 2 source locations in the translation unit.
310  ///
311  /// \returns true if this source location comes before 'Loc', false otherwise.
312  bool isBeforeInTranslationUnitThan(SourceLocation Loc) const;
313
314  /// \brief Determines the order of 2 source locations in the translation unit.
315  ///
316  /// \returns true if this source location comes before 'Loc', false otherwise.
317  bool isBeforeInTranslationUnitThan(FullSourceLoc Loc) const {
318    assert(Loc.isValid());
319    assert(SrcMgr == Loc.SrcMgr && "Loc comes from another SourceManager!");
320    return isBeforeInTranslationUnitThan((SourceLocation)Loc);
321  }
322
323  /// \brief Comparison function class, useful for sorting FullSourceLocs.
324  struct BeforeThanCompare : public std::binary_function<FullSourceLoc,
325                                                         FullSourceLoc, bool> {
326    bool operator()(const FullSourceLoc& lhs, const FullSourceLoc& rhs) const {
327      return lhs.isBeforeInTranslationUnitThan(rhs);
328    }
329  };
330
331  /// \brief Prints information about this FullSourceLoc to stderr.
332  ///
333  /// This is useful for debugging.
334  void dump() const;
335
336  friend inline bool
337  operator==(const FullSourceLoc &LHS, const FullSourceLoc &RHS) {
338    return LHS.getRawEncoding() == RHS.getRawEncoding() &&
339          LHS.SrcMgr == RHS.SrcMgr;
340  }
341
342  friend inline bool
343  operator!=(const FullSourceLoc &LHS, const FullSourceLoc &RHS) {
344    return !(LHS == RHS);
345  }
346
347};
348
349/// \brief Represents an unpacked "presumed" location which can be presented
350/// to the user.
351///
352/// A 'presumed' location can be modified by \#line and GNU line marker
353/// directives and is always the expansion point of a normal location.
354///
355/// You can get a PresumedLoc from a SourceLocation with SourceManager.
356class PresumedLoc {
357  const char *Filename;
358  unsigned Line, Col;
359  SourceLocation IncludeLoc;
360public:
361  PresumedLoc() : Filename(nullptr) {}
362  PresumedLoc(const char *FN, unsigned Ln, unsigned Co, SourceLocation IL)
363    : Filename(FN), Line(Ln), Col(Co), IncludeLoc(IL) {
364  }
365
366  /// \brief Return true if this object is invalid or uninitialized.
367  ///
368  /// This occurs when created with invalid source locations or when walking
369  /// off the top of a \#include stack.
370  bool isInvalid() const { return Filename == nullptr; }
371  bool isValid() const { return Filename != nullptr; }
372
373  /// \brief Return the presumed filename of this location.
374  ///
375  /// This can be affected by \#line etc.
376  const char *getFilename() const { return Filename; }
377
378  /// \brief Return the presumed line number of this location.
379  ///
380  /// This can be affected by \#line etc.
381  unsigned getLine() const { return Line; }
382
383  /// \brief Return the presumed column number of this location.
384  ///
385  /// This cannot be affected by \#line, but is packaged here for convenience.
386  unsigned getColumn() const { return Col; }
387
388  /// \brief Return the presumed include location of this location.
389  ///
390  /// This can be affected by GNU linemarker directives.
391  SourceLocation getIncludeLoc() const { return IncludeLoc; }
392};
393
394
395}  // end namespace clang
396
397namespace llvm {
398  /// Define DenseMapInfo so that FileID's can be used as keys in DenseMap and
399  /// DenseSets.
400  template <>
401  struct DenseMapInfo<clang::FileID> {
402    static inline clang::FileID getEmptyKey() {
403      return clang::FileID();
404    }
405    static inline clang::FileID getTombstoneKey() {
406      return clang::FileID::getSentinel();
407    }
408
409    static unsigned getHashValue(clang::FileID S) {
410      return S.getHashValue();
411    }
412
413    static bool isEqual(clang::FileID LHS, clang::FileID RHS) {
414      return LHS == RHS;
415    }
416  };
417
418  template <>
419  struct isPodLike<clang::SourceLocation> { static const bool value = true; };
420  template <>
421  struct isPodLike<clang::FileID> { static const bool value = true; };
422
423  // Teach SmallPtrSet how to handle SourceLocation.
424  template<>
425  class PointerLikeTypeTraits<clang::SourceLocation> {
426  public:
427    static inline void *getAsVoidPointer(clang::SourceLocation L) {
428      return L.getPtrEncoding();
429    }
430    static inline clang::SourceLocation getFromVoidPointer(void *P) {
431      return clang::SourceLocation::getFromRawEncoding((unsigned)(uintptr_t)P);
432    }
433    enum { NumLowBitsAvailable = 0 };
434  };
435
436}  // end namespace llvm
437
438#endif
439