clang  11.0.0git
Tokens.cpp
Go to the documentation of this file.
1 //===- Tokens.cpp - collect tokens from preprocessing ---------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Basic/Diagnostic.h"
12 #include "clang/Basic/LLVM.h"
16 #include "clang/Basic/TokenKinds.h"
17 #include "clang/Lex/PPCallbacks.h"
18 #include "clang/Lex/Preprocessor.h"
19 #include "clang/Lex/Token.h"
20 #include "llvm/ADT/ArrayRef.h"
21 #include "llvm/ADT/None.h"
22 #include "llvm/ADT/Optional.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/ErrorHandling.h"
26 #include "llvm/Support/FormatVariadic.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include <algorithm>
29 #include <cassert>
30 #include <iterator>
31 #include <string>
32 #include <utility>
33 #include <vector>
34 
35 using namespace clang;
36 using namespace clang::syntax;
37 
38 namespace {
39 // Finds the smallest consecutive subsuquence of Toks that covers R.
41 getTokensCovering(llvm::ArrayRef<syntax::Token> Toks, SourceRange R,
42  const SourceManager &SM) {
43  if (R.isInvalid())
44  return {};
45  const syntax::Token *Begin =
46  llvm::partition_point(Toks, [&](const syntax::Token &T) {
47  return SM.isBeforeInTranslationUnit(T.location(), R.getBegin());
48  });
49  const syntax::Token *End =
50  llvm::partition_point(Toks, [&](const syntax::Token &T) {
51  return !SM.isBeforeInTranslationUnit(R.getEnd(), T.location());
52  });
53  if (Begin > End)
54  return {};
55  return {Begin, End};
56 }
57 
58 // Finds the smallest expansion range that contains expanded tokens First and
59 // Last, e.g.:
60 // #define ID(x) x
61 // ID(ID(ID(a1) a2))
62 // ~~ -> a1
63 // ~~ -> a2
64 // ~~~~~~~~~ -> a1 a2
65 SourceRange findCommonRangeForMacroArgs(const syntax::Token &First,
66  const syntax::Token &Last,
67  const SourceManager &SM) {
68  SourceRange Res;
69  auto FirstLoc = First.location(), LastLoc = Last.location();
70  // Keep traversing up the spelling chain as longs as tokens are part of the
71  // same expansion.
72  while (!FirstLoc.isFileID() && !LastLoc.isFileID()) {
73  auto ExpInfoFirst = SM.getSLocEntry(SM.getFileID(FirstLoc)).getExpansion();
74  auto ExpInfoLast = SM.getSLocEntry(SM.getFileID(LastLoc)).getExpansion();
75  // Stop if expansions have diverged.
76  if (ExpInfoFirst.getExpansionLocStart() !=
77  ExpInfoLast.getExpansionLocStart())
78  break;
79  // Do not continue into macro bodies.
80  if (!ExpInfoFirst.isMacroArgExpansion() ||
81  !ExpInfoLast.isMacroArgExpansion())
82  break;
83  FirstLoc = SM.getImmediateSpellingLoc(FirstLoc);
84  LastLoc = SM.getImmediateSpellingLoc(LastLoc);
85  // Update the result afterwards, as we want the tokens that triggered the
86  // expansion.
87  Res = {FirstLoc, LastLoc};
88  }
89  // Normally mapping back to expansion location here only changes FileID, as
90  // we've already found some tokens expanded from the same macro argument, and
91  // they should map to a consecutive subset of spelled tokens. Unfortunately
92  // SourceManager::isBeforeInTranslationUnit discriminates sourcelocations
93  // based on their FileID in addition to offsets. So even though we are
94  // referring to same tokens, SourceManager might tell us that one is before
95  // the other if they've got different FileIDs.
96  return SM.getExpansionRange(CharSourceRange(Res, true)).getAsRange();
97 }
98 
99 } // namespace
100 
101 syntax::Token::Token(SourceLocation Location, unsigned Length,
103  : Location(Location), Length(Length), Kind(Kind) {
104  assert(Location.isValid());
105 }
106 
108  : Token(T.getLocation(), T.getLength(), T.getKind()) {
109  assert(!T.isAnnotation());
110 }
111 
112 llvm::StringRef syntax::Token::text(const SourceManager &SM) const {
113  bool Invalid = false;
114  const char *Start = SM.getCharacterData(location(), &Invalid);
115  assert(!Invalid);
116  return llvm::StringRef(Start, length());
117 }
118 
120  assert(location().isFileID() && "must be a spelled token");
121  FileID File;
122  unsigned StartOffset;
123  std::tie(File, StartOffset) = SM.getDecomposedLoc(location());
124  return FileRange(File, StartOffset, StartOffset + length());
125 }
126 
128  const syntax::Token &First,
129  const syntax::Token &Last) {
130  auto F = First.range(SM);
131  auto L = Last.range(SM);
132  assert(F.file() == L.file() && "tokens from different files");
133  assert((F == L || F.endOffset() <= L.beginOffset()) &&
134  "wrong order of tokens");
135  return FileRange(F.file(), F.beginOffset(), L.endOffset());
136 }
137 
138 llvm::raw_ostream &syntax::operator<<(llvm::raw_ostream &OS, const Token &T) {
139  return OS << T.str();
140 }
141 
142 FileRange::FileRange(FileID File, unsigned BeginOffset, unsigned EndOffset)
143  : File(File), Begin(BeginOffset), End(EndOffset) {
144  assert(File.isValid());
145  assert(BeginOffset <= EndOffset);
146 }
147 
149  unsigned Length) {
150  assert(BeginLoc.isValid());
151  assert(BeginLoc.isFileID());
152 
153  std::tie(File, Begin) = SM.getDecomposedLoc(BeginLoc);
154  End = Begin + Length;
155 }
157  SourceLocation EndLoc) {
158  assert(BeginLoc.isValid());
159  assert(BeginLoc.isFileID());
160  assert(EndLoc.isValid());
161  assert(EndLoc.isFileID());
162  assert(SM.getFileID(BeginLoc) == SM.getFileID(EndLoc));
163  assert(SM.getFileOffset(BeginLoc) <= SM.getFileOffset(EndLoc));
164 
165  std::tie(File, Begin) = SM.getDecomposedLoc(BeginLoc);
166  End = SM.getFileOffset(EndLoc);
167 }
168 
169 llvm::raw_ostream &syntax::operator<<(llvm::raw_ostream &OS,
170  const FileRange &R) {
171  return OS << llvm::formatv("FileRange(file = {0}, offsets = {1}-{2})",
172  R.file().getHashValue(), R.beginOffset(),
173  R.endOffset());
174 }
175 
176 llvm::StringRef FileRange::text(const SourceManager &SM) const {
177  bool Invalid = false;
178  StringRef Text = SM.getBufferData(File, &Invalid);
179  if (Invalid)
180  return "";
181  assert(Begin <= Text.size());
182  assert(End <= Text.size());
183  return Text.substr(Begin, length());
184 }
185 
187  return getTokensCovering(expandedTokens(), R, *SourceMgr);
188 }
189 
191  return CharSourceRange(
192  SourceRange(SM.getComposedLoc(File, Begin), SM.getComposedLoc(File, End)),
193  /*IsTokenRange=*/false);
194 }
195 
196 std::pair<const syntax::Token *, const TokenBuffer::Mapping *>
197 TokenBuffer::spelledForExpandedToken(const syntax::Token *Expanded) const {
198  assert(Expanded);
199  assert(ExpandedTokens.data() <= Expanded &&
200  Expanded < ExpandedTokens.data() + ExpandedTokens.size());
201 
202  auto FileIt = Files.find(
203  SourceMgr->getFileID(SourceMgr->getExpansionLoc(Expanded->location())));
204  assert(FileIt != Files.end() && "no file for an expanded token");
205 
206  const MarkedFile &File = FileIt->second;
207 
208  unsigned ExpandedIndex = Expanded - ExpandedTokens.data();
209  // Find the first mapping that produced tokens after \p Expanded.
210  auto It = llvm::partition_point(File.Mappings, [&](const Mapping &M) {
211  return M.BeginExpanded <= ExpandedIndex;
212  });
213  // Our token could only be produced by the previous mapping.
214  if (It == File.Mappings.begin()) {
215  // No previous mapping, no need to modify offsets.
216  return {&File.SpelledTokens[ExpandedIndex - File.BeginExpanded],
217  /*Mapping=*/nullptr};
218  }
219  --It; // 'It' now points to last mapping that started before our token.
220 
221  // Check if the token is part of the mapping.
222  if (ExpandedIndex < It->EndExpanded)
223  return {&File.SpelledTokens[It->BeginSpelled], /*Mapping=*/&*It};
224 
225  // Not part of the mapping, use the index from previous mapping to compute the
226  // corresponding spelled token.
227  return {
228  &File.SpelledTokens[It->EndSpelled + (ExpandedIndex - It->EndExpanded)],
229  /*Mapping=*/nullptr};
230 }
231 
232 const TokenBuffer::Mapping *
233 TokenBuffer::mappingStartingBeforeSpelled(const MarkedFile &F,
234  const syntax::Token *Spelled) {
235  assert(F.SpelledTokens.data() <= Spelled);
236  unsigned SpelledI = Spelled - F.SpelledTokens.data();
237  assert(SpelledI < F.SpelledTokens.size());
238 
239  auto It = llvm::partition_point(F.Mappings, [SpelledI](const Mapping &M) {
240  return M.BeginSpelled <= SpelledI;
241  });
242  if (It == F.Mappings.begin())
243  return nullptr;
244  --It;
245  return &*It;
246 }
247 
250  if (Spelled.empty())
251  return {};
252  assert(Spelled.front().location().isFileID());
253 
254  auto FID = sourceManager().getFileID(Spelled.front().location());
255  auto It = Files.find(FID);
256  assert(It != Files.end());
257 
258  const MarkedFile &File = It->second;
259  // `Spelled` must be a subrange of `File.SpelledTokens`.
260  assert(File.SpelledTokens.data() <= Spelled.data());
261  assert(&Spelled.back() <=
262  File.SpelledTokens.data() + File.SpelledTokens.size());
263 #ifndef NDEBUG
264  auto T1 = Spelled.back().location();
265  auto T2 = File.SpelledTokens.back().location();
266  assert(T1 == T2 || sourceManager().isBeforeInTranslationUnit(T1, T2));
267 #endif
268 
269  auto *FrontMapping = mappingStartingBeforeSpelled(File, &Spelled.front());
270  unsigned SpelledFrontI = &Spelled.front() - File.SpelledTokens.data();
271  assert(SpelledFrontI < File.SpelledTokens.size());
272  unsigned ExpandedBegin;
273  if (!FrontMapping) {
274  // No mapping that starts before the first token of Spelled, we don't have
275  // to modify offsets.
276  ExpandedBegin = File.BeginExpanded + SpelledFrontI;
277  } else if (SpelledFrontI < FrontMapping->EndSpelled) {
278  // This mapping applies to Spelled tokens.
279  if (SpelledFrontI != FrontMapping->BeginSpelled) {
280  // Spelled tokens don't cover the entire mapping, returning empty result.
281  return {}; // FIXME: support macro arguments.
282  }
283  // Spelled tokens start at the beginning of this mapping.
284  ExpandedBegin = FrontMapping->BeginExpanded;
285  } else {
286  // Spelled tokens start after the mapping ends (they start in the hole
287  // between 2 mappings, or between a mapping and end of the file).
288  ExpandedBegin =
289  FrontMapping->EndExpanded + (SpelledFrontI - FrontMapping->EndSpelled);
290  }
291 
292  auto *BackMapping = mappingStartingBeforeSpelled(File, &Spelled.back());
293  unsigned SpelledBackI = &Spelled.back() - File.SpelledTokens.data();
294  unsigned ExpandedEnd;
295  if (!BackMapping) {
296  // No mapping that starts before the last token of Spelled, we don't have to
297  // modify offsets.
298  ExpandedEnd = File.BeginExpanded + SpelledBackI + 1;
299  } else if (SpelledBackI < BackMapping->EndSpelled) {
300  // This mapping applies to Spelled tokens.
301  if (SpelledBackI + 1 != BackMapping->EndSpelled) {
302  // Spelled tokens don't cover the entire mapping, returning empty result.
303  return {}; // FIXME: support macro arguments.
304  }
305  ExpandedEnd = BackMapping->EndExpanded;
306  } else {
307  // Spelled tokens end after the mapping ends.
308  ExpandedEnd =
309  BackMapping->EndExpanded + (SpelledBackI - BackMapping->EndSpelled) + 1;
310  }
311 
312  assert(ExpandedBegin < ExpandedTokens.size());
313  assert(ExpandedEnd < ExpandedTokens.size());
314  // Avoid returning empty ranges.
315  if (ExpandedBegin == ExpandedEnd)
316  return {};
317  return {llvm::makeArrayRef(ExpandedTokens.data() + ExpandedBegin,
318  ExpandedTokens.data() + ExpandedEnd)};
319 }
320 
322  auto It = Files.find(FID);
323  assert(It != Files.end());
324  return It->second.SpelledTokens;
325 }
326 
328  assert(Loc.isFileID());
329  const auto *Tok = llvm::partition_point(
330  spelledTokens(SourceMgr->getFileID(Loc)),
331  [&](const syntax::Token &Tok) { return Tok.location() < Loc; });
332  if (!Tok || Tok->location() != Loc)
333  return nullptr;
334  return Tok;
335 }
336 
337 std::string TokenBuffer::Mapping::str() const {
338  return std::string(
339  llvm::formatv("spelled tokens: [{0},{1}), expanded tokens: [{2},{3})",
340  BeginSpelled, EndSpelled, BeginExpanded, EndExpanded));
341 }
342 
345  // Mapping an empty range is ambiguous in case of empty mappings at either end
346  // of the range, bail out in that case.
347  if (Expanded.empty())
348  return llvm::None;
349 
350  const syntax::Token *BeginSpelled;
351  const Mapping *BeginMapping;
352  std::tie(BeginSpelled, BeginMapping) =
353  spelledForExpandedToken(&Expanded.front());
354 
355  const syntax::Token *LastSpelled;
356  const Mapping *LastMapping;
357  std::tie(LastSpelled, LastMapping) =
358  spelledForExpandedToken(&Expanded.back());
359 
360  FileID FID = SourceMgr->getFileID(BeginSpelled->location());
361  // FIXME: Handle multi-file changes by trying to map onto a common root.
362  if (FID != SourceMgr->getFileID(LastSpelled->location()))
363  return llvm::None;
364 
365  const MarkedFile &File = Files.find(FID)->second;
366 
367  // If both tokens are coming from a macro argument expansion, try and map to
368  // smallest part of the macro argument. BeginMapping && LastMapping check is
369  // only for performance, they are a prerequisite for Expanded.front() and
370  // Expanded.back() being part of a macro arg expansion.
371  if (BeginMapping && LastMapping &&
372  SourceMgr->isMacroArgExpansion(Expanded.front().location()) &&
373  SourceMgr->isMacroArgExpansion(Expanded.back().location())) {
374  auto CommonRange = findCommonRangeForMacroArgs(Expanded.front(),
375  Expanded.back(), *SourceMgr);
376  // It might be the case that tokens are arguments of different macro calls,
377  // in that case we should continue with the logic below instead of returning
378  // an empty range.
379  if (CommonRange.isValid())
380  return getTokensCovering(File.SpelledTokens, CommonRange, *SourceMgr);
381  }
382 
383  // Do not allow changes that doesn't cover full expansion.
384  unsigned BeginExpanded = Expanded.begin() - ExpandedTokens.data();
385  unsigned EndExpanded = Expanded.end() - ExpandedTokens.data();
386  if (BeginMapping && BeginExpanded != BeginMapping->BeginExpanded)
387  return llvm::None;
388  if (LastMapping && LastMapping->EndExpanded != EndExpanded)
389  return llvm::None;
390  // All is good, return the result.
391  return llvm::makeArrayRef(
392  BeginMapping ? File.SpelledTokens.data() + BeginMapping->BeginSpelled
393  : BeginSpelled,
394  LastMapping ? File.SpelledTokens.data() + LastMapping->EndSpelled
395  : LastSpelled + 1);
396 }
397 
400  assert(Spelled);
401  assert(Spelled->location().isFileID() && "not a spelled token");
402  auto FileIt = Files.find(SourceMgr->getFileID(Spelled->location()));
403  assert(FileIt != Files.end() && "file not tracked by token buffer");
404 
405  auto &File = FileIt->second;
406  assert(File.SpelledTokens.data() <= Spelled &&
407  Spelled < (File.SpelledTokens.data() + File.SpelledTokens.size()));
408 
409  unsigned SpelledIndex = Spelled - File.SpelledTokens.data();
410  auto M = llvm::partition_point(File.Mappings, [&](const Mapping &M) {
411  return M.BeginSpelled < SpelledIndex;
412  });
413  if (M == File.Mappings.end() || M->BeginSpelled != SpelledIndex)
414  return llvm::None;
415 
416  Expansion E;
417  E.Spelled = llvm::makeArrayRef(File.SpelledTokens.data() + M->BeginSpelled,
418  File.SpelledTokens.data() + M->EndSpelled);
419  E.Expanded = llvm::makeArrayRef(ExpandedTokens.data() + M->BeginExpanded,
420  ExpandedTokens.data() + M->EndExpanded);
421  return E;
422 }
426  assert(Loc.isFileID());
427 
428  auto *Right = llvm::partition_point(
429  Tokens, [&](const syntax::Token &Tok) { return Tok.location() < Loc; });
430  bool AcceptRight = Right != Tokens.end() && Right->location() <= Loc;
431  bool AcceptLeft =
432  Right != Tokens.begin() && (Right - 1)->endLocation() >= Loc;
433  return llvm::makeArrayRef(Right - (AcceptLeft ? 1 : 0),
434  Right + (AcceptRight ? 1 : 0));
435 }
436 
439  const syntax::TokenBuffer &Tokens) {
440  return spelledTokensTouching(
441  Loc, Tokens.spelledTokens(Tokens.sourceManager().getFileID(Loc)));
442 }
443 
444 const syntax::Token *
447  for (const syntax::Token &Tok : spelledTokensTouching(Loc, Tokens)) {
448  if (Tok.kind() == tok::identifier)
449  return &Tok;
450  }
451  return nullptr;
452 }
453 
454 const syntax::Token *
456  const syntax::TokenBuffer &Tokens) {
458  Loc, Tokens.spelledTokens(Tokens.sourceManager().getFileID(Loc)));
459 }
460 
461 std::vector<const syntax::Token *>
463  auto FileIt = Files.find(FID);
464  assert(FileIt != Files.end() && "file not tracked by token buffer");
465  auto &File = FileIt->second;
466  std::vector<const syntax::Token *> Expansions;
467  auto &Spelled = File.SpelledTokens;
468  for (auto Mapping : File.Mappings) {
469  const syntax::Token *Token = &Spelled[Mapping.BeginSpelled];
470  if (Token->kind() == tok::TokenKind::identifier)
471  Expansions.push_back(Token);
472  }
473  return Expansions;
474 }
475 
476 std::vector<syntax::Token> syntax::tokenize(const FileRange &FR,
477  const SourceManager &SM,
478  const LangOptions &LO) {
479  std::vector<syntax::Token> Tokens;
480  IdentifierTable Identifiers(LO);
481  auto AddToken = [&](clang::Token T) {
482  // Fill the proper token kind for keywords, etc.
483  if (T.getKind() == tok::raw_identifier && !T.needsCleaning() &&
484  !T.hasUCN()) { // FIXME: support needsCleaning and hasUCN cases.
485  clang::IdentifierInfo &II = Identifiers.get(T.getRawIdentifier());
486  T.setIdentifierInfo(&II);
487  T.setKind(II.getTokenID());
488  }
489  Tokens.push_back(syntax::Token(T));
490  };
491 
492  auto SrcBuffer = SM.getBufferData(FR.file());
493  Lexer L(SM.getLocForStartOfFile(FR.file()), LO, SrcBuffer.data(),
494  SrcBuffer.data() + FR.beginOffset(),
495  // We can't make BufEnd point to FR.endOffset, as Lexer requires a
496  // null terminated buffer.
497  SrcBuffer.data() + SrcBuffer.size());
498 
499  clang::Token T;
500  while (!L.LexFromRawLexer(T) && L.getCurrentBufferOffset() < FR.endOffset())
501  AddToken(T);
502  // LexFromRawLexer returns true when it parses the last token of the file, add
503  // it iff it starts within the range we are interested in.
504  if (SM.getFileOffset(T.getLocation()) < FR.endOffset())
505  AddToken(T);
506  return Tokens;
507 }
508 
509 std::vector<syntax::Token> syntax::tokenize(FileID FID, const SourceManager &SM,
510  const LangOptions &LO) {
511  return tokenize(syntax::FileRange(FID, 0, SM.getFileIDSize(FID)), SM, LO);
512 }
513 
514 /// Records information reqired to construct mappings for the token buffer that
515 /// we are collecting.
517 public:
518  CollectPPExpansions(TokenCollector &C) : Collector(&C) {}
519 
520  /// Disabled instance will stop reporting anything to TokenCollector.
521  /// This ensures that uses of the preprocessor after TokenCollector::consume()
522  /// is called do not access the (possibly invalid) collector instance.
523  void disable() { Collector = nullptr; }
524 
525  void MacroExpands(const clang::Token &MacroNameTok, const MacroDefinition &MD,
526  SourceRange Range, const MacroArgs *Args) override {
527  if (!Collector)
528  return;
529  const auto &SM = Collector->PP.getSourceManager();
530  // Only record top-level expansions that directly produce expanded tokens.
531  // This excludes those where:
532  // - the macro use is inside a macro body,
533  // - the macro appears in an argument to another macro.
534  // However macro expansion isn't really a tree, it's token rewrite rules,
535  // so there are other cases, e.g.
536  // #define B(X) X
537  // #define A 1 + B
538  // A(2)
539  // Both A and B produce expanded tokens, though the macro name 'B' comes
540  // from an expansion. The best we can do is merge the mappings for both.
541 
542  // The *last* token of any top-level macro expansion must be in a file.
543  // (In the example above, see the closing paren of the expansion of B).
544  if (!Range.getEnd().isFileID())
545  return;
546  // If there's a current expansion that encloses this one, this one can't be
547  // top-level.
548  if (LastExpansionEnd.isValid() &&
549  !SM.isBeforeInTranslationUnit(LastExpansionEnd, Range.getEnd()))
550  return;
551 
552  // If the macro invocation (B) starts in a macro (A) but ends in a file,
553  // we'll create a merged mapping for A + B by overwriting the endpoint for
554  // A's startpoint.
555  if (!Range.getBegin().isFileID()) {
556  Range.setBegin(SM.getExpansionLoc(Range.getBegin()));
557  assert(Collector->Expansions.count(Range.getBegin().getRawEncoding()) &&
558  "Overlapping macros should have same expansion location");
559  }
560 
561  Collector->Expansions[Range.getBegin().getRawEncoding()] = Range.getEnd();
562  LastExpansionEnd = Range.getEnd();
563  }
564  // FIXME: handle directives like #pragma, #include, etc.
565 private:
566  TokenCollector *Collector;
567  /// Used to detect recursive macro expansions.
568  SourceLocation LastExpansionEnd;
569 };
570 
571 /// Fills in the TokenBuffer by tracing the run of a preprocessor. The
572 /// implementation tracks the tokens, macro expansions and directives coming
573 /// from the preprocessor and:
574 /// - for each token, figures out if it is a part of an expanded token stream,
575 /// spelled token stream or both. Stores the tokens appropriately.
576 /// - records mappings from the spelled to expanded token ranges, e.g. for macro
577 /// expansions.
578 /// FIXME: also properly record:
579 /// - #include directives,
580 /// - #pragma, #line and other PP directives,
581 /// - skipped pp regions,
582 /// - ...
583 
585  // Collect the expanded token stream during preprocessing.
586  PP.setTokenWatcher([this](const clang::Token &T) {
587  if (T.isAnnotation())
588  return;
589  DEBUG_WITH_TYPE("collect-tokens", llvm::dbgs()
590  << "Token: "
591  << syntax::Token(T).dumpForTests(
592  this->PP.getSourceManager())
593  << "\n"
594 
595  );
596  Expanded.push_back(syntax::Token(T));
597  });
598  // And locations of macro calls, to properly recover boundaries of those in
599  // case of empty expansions.
600  auto CB = std::make_unique<CollectPPExpansions>(*this);
601  this->Collector = CB.get();
602  PP.addPPCallbacks(std::move(CB));
603 }
604 
605 /// Builds mappings and spelled tokens in the TokenBuffer based on the expanded
606 /// token stream.
608 public:
609  Builder(std::vector<syntax::Token> Expanded, PPExpansions CollectedExpansions,
610  const SourceManager &SM, const LangOptions &LangOpts)
611  : Result(SM), CollectedExpansions(std::move(CollectedExpansions)), SM(SM),
612  LangOpts(LangOpts) {
613  Result.ExpandedTokens = std::move(Expanded);
614  }
615 
617  assert(!Result.ExpandedTokens.empty());
618  assert(Result.ExpandedTokens.back().kind() == tok::eof);
619 
620  // Tokenize every file that contributed tokens to the expanded stream.
621  buildSpelledTokens();
622 
623  // The expanded token stream consists of runs of tokens that came from
624  // the same source (a macro expansion, part of a file etc).
625  // Between these runs are the logical positions of spelled tokens that
626  // didn't expand to anything.
627  while (NextExpanded < Result.ExpandedTokens.size() - 1 /* eof */) {
628  // Create empty mappings for spelled tokens that expanded to nothing here.
629  // May advance NextSpelled, but NextExpanded is unchanged.
630  discard();
631  // Create mapping for a contiguous run of expanded tokens.
632  // Advances NextExpanded past the run, and NextSpelled accordingly.
633  unsigned OldPosition = NextExpanded;
634  advance();
635  if (NextExpanded == OldPosition)
636  diagnoseAdvanceFailure();
637  }
638  // If any tokens remain in any of the files, they didn't expand to anything.
639  // Create empty mappings up until the end of the file.
640  for (const auto &File : Result.Files)
641  discard(File.first);
642 
643 #ifndef NDEBUG
644  for (auto &pair : Result.Files) {
645  auto &mappings = pair.second.Mappings;
646  assert(llvm::is_sorted(mappings, [](const TokenBuffer::Mapping &M1,
647  const TokenBuffer::Mapping &M2) {
648  return M1.BeginSpelled < M2.BeginSpelled &&
649  M1.EndSpelled < M2.EndSpelled &&
650  M1.BeginExpanded < M2.BeginExpanded &&
651  M1.EndExpanded < M2.EndExpanded;
652  }));
653  }
654 #endif
655 
656  return std::move(Result);
657  }
658 
659 private:
660  // Consume a sequence of spelled tokens that didn't expand to anything.
661  // In the simplest case, skips spelled tokens until finding one that produced
662  // the NextExpanded token, and creates an empty mapping for them.
663  // If Drain is provided, skips remaining tokens from that file instead.
664  void discard(llvm::Optional<FileID> Drain = llvm::None) {
666  Drain ? SM.getLocForEndOfFile(*Drain)
667  : SM.getExpansionLoc(
668  Result.ExpandedTokens[NextExpanded].location());
669  FileID File = SM.getFileID(Target);
670  const auto &SpelledTokens = Result.Files[File].SpelledTokens;
671  auto &NextSpelled = this->NextSpelled[File];
672 
673  TokenBuffer::Mapping Mapping;
674  Mapping.BeginSpelled = NextSpelled;
675  // When dropping trailing tokens from a file, the empty mapping should
676  // be positioned within the file's expanded-token range (at the end).
677  Mapping.BeginExpanded = Mapping.EndExpanded =
678  Drain ? Result.Files[*Drain].EndExpanded : NextExpanded;
679  // We may want to split into several adjacent empty mappings.
680  // FlushMapping() emits the current mapping and starts a new one.
681  auto FlushMapping = [&, this] {
682  Mapping.EndSpelled = NextSpelled;
683  if (Mapping.BeginSpelled != Mapping.EndSpelled)
684  Result.Files[File].Mappings.push_back(Mapping);
685  Mapping.BeginSpelled = NextSpelled;
686  };
687 
688  while (NextSpelled < SpelledTokens.size() &&
689  SpelledTokens[NextSpelled].location() < Target) {
690  // If we know mapping bounds at [NextSpelled, KnownEnd] (macro expansion)
691  // then we want to partition our (empty) mapping.
692  // [Start, NextSpelled) [NextSpelled, KnownEnd] (KnownEnd, Target)
693  SourceLocation KnownEnd = CollectedExpansions.lookup(
694  SpelledTokens[NextSpelled].location().getRawEncoding());
695  if (KnownEnd.isValid()) {
696  FlushMapping(); // Emits [Start, NextSpelled)
697  while (NextSpelled < SpelledTokens.size() &&
698  SpelledTokens[NextSpelled].location() <= KnownEnd)
699  ++NextSpelled;
700  FlushMapping(); // Emits [NextSpelled, KnownEnd]
701  // Now the loop contitues and will emit (KnownEnd, Target).
702  } else {
703  ++NextSpelled;
704  }
705  }
706  FlushMapping();
707  }
708 
709  // Consumes the NextExpanded token and others that are part of the same run.
710  // Increases NextExpanded and NextSpelled by at least one, and adds a mapping
711  // (unless this is a run of file tokens, which we represent with no mapping).
712  void advance() {
713  const syntax::Token &Tok = Result.ExpandedTokens[NextExpanded];
714  SourceLocation Expansion = SM.getExpansionLoc(Tok.location());
715  FileID File = SM.getFileID(Expansion);
716  const auto &SpelledTokens = Result.Files[File].SpelledTokens;
717  auto &NextSpelled = this->NextSpelled[File];
718 
719  if (Tok.location().isFileID()) {
720  // A run of file tokens continues while the expanded/spelled tokens match.
721  while (NextSpelled < SpelledTokens.size() &&
722  NextExpanded < Result.ExpandedTokens.size() &&
723  SpelledTokens[NextSpelled].location() ==
724  Result.ExpandedTokens[NextExpanded].location()) {
725  ++NextSpelled;
726  ++NextExpanded;
727  }
728  // We need no mapping for file tokens copied to the expanded stream.
729  } else {
730  // We found a new macro expansion. We should have its spelling bounds.
731  auto End = CollectedExpansions.lookup(Expansion.getRawEncoding());
732  assert(End.isValid() && "Macro expansion wasn't captured?");
733 
734  // Mapping starts here...
735  TokenBuffer::Mapping Mapping;
736  Mapping.BeginExpanded = NextExpanded;
737  Mapping.BeginSpelled = NextSpelled;
738  // ... consumes spelled tokens within bounds we captured ...
739  while (NextSpelled < SpelledTokens.size() &&
740  SpelledTokens[NextSpelled].location() <= End)
741  ++NextSpelled;
742  // ... consumes expanded tokens rooted at the same expansion ...
743  while (NextExpanded < Result.ExpandedTokens.size() &&
744  SM.getExpansionLoc(
745  Result.ExpandedTokens[NextExpanded].location()) == Expansion)
746  ++NextExpanded;
747  // ... and ends here.
748  Mapping.EndExpanded = NextExpanded;
749  Mapping.EndSpelled = NextSpelled;
750  Result.Files[File].Mappings.push_back(Mapping);
751  }
752  }
753 
754  // advance() is supposed to consume at least one token - if not, we crash.
755  void diagnoseAdvanceFailure() {
756 #ifndef NDEBUG
757  // Show the failed-to-map token in context.
758  for (unsigned I = (NextExpanded < 10) ? 0 : NextExpanded - 10;
759  I < NextExpanded + 5 && I < Result.ExpandedTokens.size(); ++I) {
760  const char *L =
761  (I == NextExpanded) ? "!! " : (I < NextExpanded) ? "ok " : " ";
762  llvm::errs() << L << Result.ExpandedTokens[I].dumpForTests(SM) << "\n";
763  }
764 #endif
765  llvm_unreachable("Couldn't map expanded token to spelled tokens!");
766  }
767 
768  /// Initializes TokenBuffer::Files and fills spelled tokens and expanded
769  /// ranges for each of the files.
770  void buildSpelledTokens() {
771  for (unsigned I = 0; I < Result.ExpandedTokens.size(); ++I) {
772  const auto &Tok = Result.ExpandedTokens[I];
773  auto FID = SM.getFileID(SM.getExpansionLoc(Tok.location()));
774  auto It = Result.Files.try_emplace(FID);
775  TokenBuffer::MarkedFile &File = It.first->second;
776 
777  // The eof token should not be considered part of the main-file's range.
778  File.EndExpanded = Tok.kind() == tok::eof ? I : I + 1;
779 
780  if (!It.second)
781  continue; // we have seen this file before.
782  // This is the first time we see this file.
783  File.BeginExpanded = I;
784  File.SpelledTokens = tokenize(FID, SM, LangOpts);
785  }
786  }
787 
788  TokenBuffer Result;
789  unsigned NextExpanded = 0; // cursor in ExpandedTokens
790  llvm::DenseMap<FileID, unsigned> NextSpelled; // cursor in SpelledTokens
791  PPExpansions CollectedExpansions;
792  const SourceManager &SM;
793  const LangOptions &LangOpts;
794 };
795 
797  PP.setTokenWatcher(nullptr);
798  Collector->disable();
799  return Builder(std::move(Expanded), std::move(Expansions),
800  PP.getSourceManager(), PP.getLangOpts())
801  .build();
802 }
803 
804 std::string syntax::Token::str() const {
805  return std::string(llvm::formatv("Token({0}, length = {1})",
806  tok::getTokenName(kind()), length()));
807 }
808 
809 std::string syntax::Token::dumpForTests(const SourceManager &SM) const {
810  return std::string(llvm::formatv("Token(`{0}`, {1}, length = {2})", text(SM),
811  tok::getTokenName(kind()), length()));
812 }
813 
814 std::string TokenBuffer::dumpForTests() const {
815  auto PrintToken = [this](const syntax::Token &T) -> std::string {
816  if (T.kind() == tok::eof)
817  return "<eof>";
818  return std::string(T.text(*SourceMgr));
819  };
820 
821  auto DumpTokens = [this, &PrintToken](llvm::raw_ostream &OS,
823  if (Tokens.empty()) {
824  OS << "<empty>";
825  return;
826  }
827  OS << Tokens[0].text(*SourceMgr);
828  for (unsigned I = 1; I < Tokens.size(); ++I) {
829  if (Tokens[I].kind() == tok::eof)
830  continue;
831  OS << " " << PrintToken(Tokens[I]);
832  }
833  };
834 
835  std::string Dump;
836  llvm::raw_string_ostream OS(Dump);
837 
838  OS << "expanded tokens:\n"
839  << " ";
840  // (!) we do not show '<eof>'.
841  DumpTokens(OS, llvm::makeArrayRef(ExpandedTokens).drop_back());
842  OS << "\n";
843 
844  std::vector<FileID> Keys;
845  for (auto F : Files)
846  Keys.push_back(F.first);
847  llvm::sort(Keys);
848 
849  for (FileID ID : Keys) {
850  const MarkedFile &File = Files.find(ID)->second;
851  auto *Entry = SourceMgr->getFileEntryForID(ID);
852  if (!Entry)
853  continue; // Skip builtin files.
854  OS << llvm::formatv("file '{0}'\n", Entry->getName())
855  << " spelled tokens:\n"
856  << " ";
857  DumpTokens(OS, File.SpelledTokens);
858  OS << "\n";
859 
860  if (File.Mappings.empty()) {
861  OS << " no mappings.\n";
862  continue;
863  }
864  OS << " mappings:\n";
865  for (auto &M : File.Mappings) {
866  OS << llvm::formatv(
867  " ['{0}'_{1}, '{2}'_{3}) => ['{4}'_{5}, '{6}'_{7})\n",
868  PrintToken(File.SpelledTokens[M.BeginSpelled]), M.BeginSpelled,
869  M.EndSpelled == File.SpelledTokens.size()
870  ? "<eof>"
871  : PrintToken(File.SpelledTokens[M.EndSpelled]),
872  M.EndSpelled, PrintToken(ExpandedTokens[M.BeginExpanded]),
873  M.BeginExpanded, PrintToken(ExpandedTokens[M.EndExpanded]),
874  M.EndExpanded);
875  }
876  }
877  return OS.str();
878 }
SourceLocation getLocForStartOfFile(FileID FID) const
Return the source location corresponding to the first byte of the specified file. ...
llvm::StringRef text(const SourceManager &SM) const
Gets the substring that this FileRange refers to.
Definition: Tokens.cpp:176
const SourceManager & sourceManager() const
Definition: Tokens.h:301
Lexer - This provides a simple interface that turns a text buffer into a stream of tokens...
Definition: Lexer.h:76
unsigned getRawEncoding() const
When a SourceLocation itself cannot be used, this returns an (opaque) 32-bit integer encoding for it...
SourceLocation getLocForEndOfFile(FileID FID) const
Return the source location corresponding to the last byte of the specified file.
llvm::ArrayRef< syntax::Token > spelledTokensTouching(SourceLocation Loc, const syntax::TokenBuffer &Tokens)
The spelled tokens that overlap or touch a spelling location Loc.
Definition: Tokens.cpp:438
Defines the SourceManager interface.
TokenBuffer build() &&
Definition: Tokens.cpp:616
llvm::raw_ostream & operator<<(llvm::raw_ostream &OS, NodeKind K)
For debugging purposes.
Definition: Nodes.cpp:13
bool isBeforeInTranslationUnit(SourceLocation LHS, SourceLocation RHS) const
Determines the order of 2 source locations in the translation unit.
const char * getCharacterData(SourceLocation SL, bool *Invalid=nullptr) const
Return a pointer to the start of the specified location in the appropriate spelling MemoryBuffer...
A description of the current definition of a macro.
Definition: MacroInfo.h:564
std::string str() const
For debugging purposes.
Definition: Tokens.cpp:804
std::vector< const syntax::Token * > macroExpansions(FileID FID) const
Get all tokens that expand a macro in FID.
Definition: Tokens.cpp:462
StringRef getBufferData(FileID FID, bool *Invalid=nullptr) const
Return a StringRef to the source buffer data for the specified FileID.
A token coming directly from a file or from a macro invocation.
Definition: Tokens.h:104
FileRange(FileID File, unsigned BeginOffset, unsigned EndOffset)
EXPECTS: File.isValid() && Begin <= End.
Definition: Tokens.cpp:142
void setBegin(SourceLocation b)
llvm::Optional< llvm::ArrayRef< syntax::Token > > spelledForExpanded(llvm::ArrayRef< syntax::Token > Expanded) const
Returns the subrange of spelled tokens corresponding to AST node spanning Expanded.
Definition: Tokens.cpp:344
CollectPPExpansions(TokenCollector &C)
Definition: Tokens.cpp:518
This interface provides a way to observe the actions of the preprocessor as it does its thing...
Definition: PPCallbacks.h:35
bool isAnnotation() const
Return true if this is any of tok::annot_* kind tokens.
Definition: Token.h:120
One of these records is kept for each identifier that is lexed.
Definition: Format.h:2679
unsigned getHashValue() const
const syntax::Token * spelledTokenAt(SourceLocation Loc) const
Returns the spelled Token starting at Loc, if there are no such tokens returns nullptr.
Definition: Tokens.cpp:327
Records information reqired to construct mappings for the token buffer that we are collecting...
Definition: Tokens.cpp:516
llvm::ArrayRef< syntax::Token > expandedTokens() const
All tokens produced by the preprocessor after all macro replacements, directives, etc...
Definition: Tokens.h:191
Token - This structure provides full information about a lexed token.
Definition: Token.h:34
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:54
llvm::ArrayRef< syntax::Token > Spelled
Definition: Tokens.h:270
SourceLocation getComposedLoc(FileID FID, unsigned Offset) const
Form a SourceLocation from a FileID and Offset pair.
llvm::Optional< Expansion > expansionStartingAt(const syntax::Token *Spelled) const
If Spelled starts a mapping (e.g.
Definition: Tokens.cpp:399
tok::TokenKind getTokenID() const
If this is a source-language token (e.g.
const FormatToken & Tok
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
SourceLocation getExpansionLoc(SourceLocation Loc) const
Given a SourceLocation object Loc, return the expansion location referenced by the ID...
SourceLocation location() const
Location of the first character of a token.
Definition: Tokens.h:112
CharSourceRange toCharRange(const SourceManager &SM) const
Convert to the clang range.
Definition: Tokens.cpp:190
Defines the Diagnostic-related interfaces.
void setTokenWatcher(llvm::unique_function< void(const clang::Token &)> F)
Register a function that would be called on each token in the final expanded token stream...
unsigned getFileIDSize(FileID FID) const
The size of the SLocEntry that FID represents.
LLVM_NODISCARD TokenBuffer consume() &&
Finalizes token collection.
Definition: Tokens.cpp:796
Builder(std::vector< syntax::Token > Expanded, PPExpansions CollectedExpansions, const SourceManager &SM, const LangOptions &LangOpts)
Definition: Tokens.cpp:609
Dump out preprocessed tokens.
unsigned length() const
Definition: Tokens.h:117
bool isValid() const
SourceLocation getImmediateSpellingLoc(SourceLocation Loc) const
Given a SourceLocation object, return the spelling location referenced by the ID. ...
Defines the clang::LangOptions interface.
llvm::StringRef text(const SourceManager &SM) const
Get the substring covered by the token.
Definition: Tokens.cpp:112
SourceLocation End
Represents a character-granular source range.
Implements an efficient mapping from strings to IdentifierInfo nodes.
MacroArgs - An instance of this class captures information about the formal arguments specified to a ...
Definition: MacroArgs.h:29
void disable()
Disabled instance will stop reporting anything to TokenCollector.
Definition: Tokens.cpp:523
Defines the clang::Preprocessor interface.
SourceLocation Begin
Defines the clang::IdentifierInfo, clang::IdentifierTable, and clang::Selector interfaces.
bool isInvalid() const
SourceLocation getEnd() const
#define SM(sm)
Definition: Cuda.cpp:62
unsigned length() const
Definition: Tokens.h:67
float __ovld __cnfn length(float p)
Return the length of vector p, i.e., sqrt(p.x2 + p.y 2 + ...)
SourceManager & getSourceManager() const
Definition: Preprocessor.h:919
TokenCollector(Preprocessor &P)
Adds the hooks to collect the tokens.
Definition: Tokens.cpp:584
const syntax::Token * spelledIdentifierTouching(SourceLocation Loc, llvm::ArrayRef< syntax::Token > Tokens)
The identifier token that overlaps or touches a spelling location Loc.
Definition: Tokens.cpp:445
unsigned getFileOffset(SourceLocation SpellingLoc) const
Returns the offset from the start of the file that the specified SourceLocation represents.
Kind
Encodes a location in the source.
IdentifierInfo & get(StringRef Name)
Return the identifier token info for the specified named identifier.
llvm::SmallVector< llvm::ArrayRef< syntax::Token >, 1 > expandedForSpelled(llvm::ArrayRef< syntax::Token > Spelled) const
Find the subranges of expanded tokens, corresponding to Spelled.
Definition: Tokens.cpp:249
std::string dumpForTests(const SourceManager &SM) const
Definition: Tokens.cpp:809
tok::TokenKind kind() const
Definition: Tokens.h:110
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:25
static ParseState advance(ParseState S, size_t N)
Definition: Parsing.cpp:145
FileID file() const
Definition: Tokens.h:61
An opaque identifier used by SourceManager which refers to a source file (MemoryBuffer) along with it...
SourceRange getAsRange() const
unsigned beginOffset() const
Start is a start offset (inclusive) in the corresponding file.
Definition: Tokens.h:63
Dataflow Directional Tag Classes.
bool isValid() const
Return true if this is a valid SourceLocation object.
A half-open character range inside a particular file, the start offset is included and the end offset...
Definition: Tokens.h:51
FileID getFileID(SourceLocation SpellingLoc) const
Return the FileID for a SourceLocation.
Collects tokens for the main file while running the frontend action.
Definition: Tokens.h:402
std::vector< syntax::Token > tokenize(FileID FID, const SourceManager &SM, const LangOptions &LO)
Lex the text buffer, corresponding to FID, in raw mode and record the resulting spelled tokens...
Definition: Tokens.cpp:509
CharSourceRange getExpansionRange(SourceLocation Loc) const
Given a SourceLocation object, return the range of tokens covered by the expansion in the ultimate fi...
Defines the PPCallbacks interface.
Defines the clang::TokenKind enum and support functions.
const SrcMgr::SLocEntry & getSLocEntry(FileID FID, bool *Invalid=nullptr) const
Defines the clang::SourceLocation class and associated facilities.
Builds mappings and spelled tokens in the TokenBuffer based on the expanded token stream...
Definition: Tokens.cpp:607
An expansion produced by the preprocessor, includes macro expansions and preprocessor directives...
Definition: Tokens.h:269
Token(SourceLocation Location, unsigned Length, tok::TokenKind Kind)
Definition: Tokens.cpp:101
unsigned kind
All of the diagnostics that can be emitted by the frontend.
Definition: DiagnosticIDs.h:60
const char * getTokenName(TokenKind Kind) LLVM_READNONE
Determines the name of a token as used within the front end.
Definition: TokenKinds.cpp:24
static Decl::Kind getKind(const Decl *D)
Definition: DeclBase.cpp:996
std::string dumpForTests() const
Definition: Tokens.cpp:814
StringRef Text
Definition: Format.cpp:2019
llvm::ArrayRef< syntax::Token > spelledTokens(FileID FID) const
Lexed tokens of a file before preprocessing.
Definition: Tokens.cpp:321
A list of tokens obtained by preprocessing a text buffer and operations to map between the expanded a...
Definition: Tokens.h:175
FileRange range(const SourceManager &SM) const
Gets a range of this token.
Definition: Tokens.cpp:119
A trivial tuple used to represent a source range.
llvm::ArrayRef< syntax::Token > Expanded
Definition: Tokens.h:271
unsigned endOffset() const
End offset (exclusive) in the corresponding file.
Definition: Tokens.h:65
SourceLocation getBegin() const
void addPPCallbacks(std::unique_ptr< PPCallbacks > C)
This class handles loading and caching of source files into memory.
void MacroExpands(const clang::Token &MacroNameTok, const MacroDefinition &MD, SourceRange Range, const MacroArgs *Args) override
Called by Preprocessor::HandleMacroExpandedIdentifier when a macro invocation is found.
Definition: Tokens.cpp:525
std::pair< FileID, unsigned > getDecomposedLoc(SourceLocation Loc) const
Decompose the specified location into a raw FileID + Offset pair.
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:128