1//===--- Preprocess.cpp - C Language Family Preprocessor Implementation ---===//
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//  This file implements the Preprocessor interface.
11//
12//===----------------------------------------------------------------------===//
13//
14// Options to support:
15//   -H       - Print the name of each header file used.
16//   -d[DNI] - Dump various things.
17//   -fworking-directory - #line's with preprocessor's working dir.
18//   -fpreprocessed
19//   -dependency-file,-M,-MM,-MF,-MG,-MP,-MT,-MQ,-MD,-MMD
20//   -W*
21//   -w
22//
23// Messages to emit:
24//   "Multiple include guards may be useful for:\n"
25//
26//===----------------------------------------------------------------------===//
27
28#include "clang/Lex/Preprocessor.h"
29#include "clang/Lex/MacroArgs.h"
30#include "clang/Basic/FileManager.h"
31#include "clang/Basic/SourceManager.h"
32#include "clang/Basic/TargetInfo.h"
33#include "clang/Lex/CodeCompletionHandler.h"
34#include "clang/Lex/ExternalPreprocessorSource.h"
35#include "clang/Lex/HeaderSearch.h"
36#include "clang/Lex/LexDiagnostic.h"
37#include "clang/Lex/LiteralSupport.h"
38#include "clang/Lex/MacroInfo.h"
39#include "clang/Lex/ModuleLoader.h"
40#include "clang/Lex/Pragma.h"
41#include "clang/Lex/PreprocessingRecord.h"
42#include "clang/Lex/PreprocessorOptions.h"
43#include "clang/Lex/ScratchBuffer.h"
44#include "llvm/ADT/APFloat.h"
45#include "llvm/ADT/SmallString.h"
46#include "llvm/ADT/STLExtras.h"
47#include "llvm/ADT/StringExtras.h"
48#include "llvm/Support/Capacity.h"
49#include "llvm/Support/ConvertUTF.h"
50#include "llvm/Support/MemoryBuffer.h"
51#include "llvm/Support/raw_ostream.h"
52using namespace clang;
53
54//===----------------------------------------------------------------------===//
55ExternalPreprocessorSource::~ExternalPreprocessorSource() { }
56
57Preprocessor::Preprocessor(IntrusiveRefCntPtr<PreprocessorOptions> PPOpts,
58                           DiagnosticsEngine &diags, LangOptions &opts,
59                           const TargetInfo *target, SourceManager &SM,
60                           HeaderSearch &Headers, ModuleLoader &TheModuleLoader,
61                           IdentifierInfoLookup *IILookup, bool OwnsHeaders,
62                           bool DelayInitialization, bool IncrProcessing)
63    : PPOpts(PPOpts), Diags(&diags), LangOpts(opts), Target(target),
64      FileMgr(Headers.getFileMgr()), SourceMgr(SM), HeaderInfo(Headers),
65      TheModuleLoader(TheModuleLoader), ExternalSource(0),
66      Identifiers(opts, IILookup), IncrementalProcessing(IncrProcessing),
67      CodeComplete(0), CodeCompletionFile(0), CodeCompletionOffset(0),
68      CodeCompletionReached(0), SkipMainFilePreamble(0, true), CurPPLexer(0),
69      CurDirLookup(0), CurLexerKind(CLK_Lexer), Callbacks(0),
70      MacroArgCache(0), Record(0), MIChainHead(0), MICache(0),
71      DeserialMIChainHead(0) {
72  OwnsHeaderSearch = OwnsHeaders;
73
74  ScratchBuf = new ScratchBuffer(SourceMgr);
75  CounterValue = 0; // __COUNTER__ starts at 0.
76
77  // Clear stats.
78  NumDirectives = NumDefined = NumUndefined = NumPragma = 0;
79  NumIf = NumElse = NumEndif = 0;
80  NumEnteredSourceFiles = 0;
81  NumMacroExpanded = NumFnMacroExpanded = NumBuiltinMacroExpanded = 0;
82  NumFastMacroExpanded = NumTokenPaste = NumFastTokenPaste = 0;
83  MaxIncludeStackDepth = 0;
84  NumSkipped = 0;
85
86  // Default to discarding comments.
87  KeepComments = false;
88  KeepMacroComments = false;
89  SuppressIncludeNotFoundError = false;
90
91  // Macro expansion is enabled.
92  DisableMacroExpansion = false;
93  MacroExpansionInDirectivesOverride = false;
94  InMacroArgs = false;
95  InMacroArgPreExpansion = false;
96  NumCachedTokenLexers = 0;
97  PragmasEnabled = true;
98  ParsingIfOrElifDirective = false;
99  PreprocessedOutput = false;
100
101  CachedLexPos = 0;
102
103  // We haven't read anything from the external source.
104  ReadMacrosFromExternalSource = false;
105
106  // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
107  // This gets unpoisoned where it is allowed.
108  (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned();
109  SetPoisonReason(Ident__VA_ARGS__,diag::ext_pp_bad_vaargs_use);
110
111  // Initialize the pragma handlers.
112  PragmaHandlers = new PragmaNamespace(StringRef());
113  RegisterBuiltinPragmas();
114
115  // Initialize builtin macros like __LINE__ and friends.
116  RegisterBuiltinMacros();
117
118  if(LangOpts.Borland) {
119    Ident__exception_info        = getIdentifierInfo("_exception_info");
120    Ident___exception_info       = getIdentifierInfo("__exception_info");
121    Ident_GetExceptionInfo       = getIdentifierInfo("GetExceptionInformation");
122    Ident__exception_code        = getIdentifierInfo("_exception_code");
123    Ident___exception_code       = getIdentifierInfo("__exception_code");
124    Ident_GetExceptionCode       = getIdentifierInfo("GetExceptionCode");
125    Ident__abnormal_termination  = getIdentifierInfo("_abnormal_termination");
126    Ident___abnormal_termination = getIdentifierInfo("__abnormal_termination");
127    Ident_AbnormalTermination    = getIdentifierInfo("AbnormalTermination");
128  } else {
129    Ident__exception_info = Ident__exception_code = Ident__abnormal_termination = 0;
130    Ident___exception_info = Ident___exception_code = Ident___abnormal_termination = 0;
131    Ident_GetExceptionInfo = Ident_GetExceptionCode = Ident_AbnormalTermination = 0;
132  }
133
134  if (!DelayInitialization) {
135    assert(Target && "Must provide target information for PP initialization");
136    Initialize(*Target);
137  }
138}
139
140Preprocessor::~Preprocessor() {
141  assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
142
143  while (!IncludeMacroStack.empty()) {
144    delete IncludeMacroStack.back().TheLexer;
145    delete IncludeMacroStack.back().TheTokenLexer;
146    IncludeMacroStack.pop_back();
147  }
148
149  // Free any macro definitions.
150  for (MacroInfoChain *I = MIChainHead ; I ; I = I->Next)
151    I->MI.Destroy();
152
153  // Free any cached macro expanders.
154  for (unsigned i = 0, e = NumCachedTokenLexers; i != e; ++i)
155    delete TokenLexerCache[i];
156
157  for (DeserializedMacroInfoChain *I = DeserialMIChainHead ; I ; I = I->Next)
158    I->MI.Destroy();
159
160  // Free any cached MacroArgs.
161  for (MacroArgs *ArgList = MacroArgCache; ArgList; )
162    ArgList = ArgList->deallocate();
163
164  // Release pragma information.
165  delete PragmaHandlers;
166
167  // Delete the scratch buffer info.
168  delete ScratchBuf;
169
170  // Delete the header search info, if we own it.
171  if (OwnsHeaderSearch)
172    delete &HeaderInfo;
173
174  delete Callbacks;
175}
176
177void Preprocessor::Initialize(const TargetInfo &Target) {
178  assert((!this->Target || this->Target == &Target) &&
179         "Invalid override of target information");
180  this->Target = &Target;
181
182  // Initialize information about built-ins.
183  BuiltinInfo.InitializeTarget(Target);
184  HeaderInfo.setTarget(Target);
185}
186
187void Preprocessor::setPTHManager(PTHManager* pm) {
188  PTH.reset(pm);
189  FileMgr.addStatCache(PTH->createStatCache());
190}
191
192void Preprocessor::DumpToken(const Token &Tok, bool DumpFlags) const {
193  llvm::errs() << tok::getTokenName(Tok.getKind()) << " '"
194               << getSpelling(Tok) << "'";
195
196  if (!DumpFlags) return;
197
198  llvm::errs() << "\t";
199  if (Tok.isAtStartOfLine())
200    llvm::errs() << " [StartOfLine]";
201  if (Tok.hasLeadingSpace())
202    llvm::errs() << " [LeadingSpace]";
203  if (Tok.isExpandDisabled())
204    llvm::errs() << " [ExpandDisabled]";
205  if (Tok.needsCleaning()) {
206    const char *Start = SourceMgr.getCharacterData(Tok.getLocation());
207    llvm::errs() << " [UnClean='" << StringRef(Start, Tok.getLength())
208                 << "']";
209  }
210
211  llvm::errs() << "\tLoc=<";
212  DumpLocation(Tok.getLocation());
213  llvm::errs() << ">";
214}
215
216void Preprocessor::DumpLocation(SourceLocation Loc) const {
217  Loc.dump(SourceMgr);
218}
219
220void Preprocessor::DumpMacro(const MacroInfo &MI) const {
221  llvm::errs() << "MACRO: ";
222  for (unsigned i = 0, e = MI.getNumTokens(); i != e; ++i) {
223    DumpToken(MI.getReplacementToken(i));
224    llvm::errs() << "  ";
225  }
226  llvm::errs() << "\n";
227}
228
229void Preprocessor::PrintStats() {
230  llvm::errs() << "\n*** Preprocessor Stats:\n";
231  llvm::errs() << NumDirectives << " directives found:\n";
232  llvm::errs() << "  " << NumDefined << " #define.\n";
233  llvm::errs() << "  " << NumUndefined << " #undef.\n";
234  llvm::errs() << "  #include/#include_next/#import:\n";
235  llvm::errs() << "    " << NumEnteredSourceFiles << " source files entered.\n";
236  llvm::errs() << "    " << MaxIncludeStackDepth << " max include stack depth\n";
237  llvm::errs() << "  " << NumIf << " #if/#ifndef/#ifdef.\n";
238  llvm::errs() << "  " << NumElse << " #else/#elif.\n";
239  llvm::errs() << "  " << NumEndif << " #endif.\n";
240  llvm::errs() << "  " << NumPragma << " #pragma.\n";
241  llvm::errs() << NumSkipped << " #if/#ifndef#ifdef regions skipped\n";
242
243  llvm::errs() << NumMacroExpanded << "/" << NumFnMacroExpanded << "/"
244             << NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, "
245             << NumFastMacroExpanded << " on the fast path.\n";
246  llvm::errs() << (NumFastTokenPaste+NumTokenPaste)
247             << " token paste (##) operations performed, "
248             << NumFastTokenPaste << " on the fast path.\n";
249
250  llvm::errs() << "\nPreprocessor Memory: " << getTotalMemory() << "B total";
251
252  llvm::errs() << "\n  BumpPtr: " << BP.getTotalMemory();
253  llvm::errs() << "\n  Macro Expanded Tokens: "
254               << llvm::capacity_in_bytes(MacroExpandedTokens);
255  llvm::errs() << "\n  Predefines Buffer: " << Predefines.capacity();
256  llvm::errs() << "\n  Macros: " << llvm::capacity_in_bytes(Macros);
257  llvm::errs() << "\n  #pragma push_macro Info: "
258               << llvm::capacity_in_bytes(PragmaPushMacroInfo);
259  llvm::errs() << "\n  Poison Reasons: "
260               << llvm::capacity_in_bytes(PoisonReasons);
261  llvm::errs() << "\n  Comment Handlers: "
262               << llvm::capacity_in_bytes(CommentHandlers) << "\n";
263}
264
265Preprocessor::macro_iterator
266Preprocessor::macro_begin(bool IncludeExternalMacros) const {
267  if (IncludeExternalMacros && ExternalSource &&
268      !ReadMacrosFromExternalSource) {
269    ReadMacrosFromExternalSource = true;
270    ExternalSource->ReadDefinedMacros();
271  }
272
273  return Macros.begin();
274}
275
276size_t Preprocessor::getTotalMemory() const {
277  return BP.getTotalMemory()
278    + llvm::capacity_in_bytes(MacroExpandedTokens)
279    + Predefines.capacity() /* Predefines buffer. */
280    + llvm::capacity_in_bytes(Macros)
281    + llvm::capacity_in_bytes(PragmaPushMacroInfo)
282    + llvm::capacity_in_bytes(PoisonReasons)
283    + llvm::capacity_in_bytes(CommentHandlers);
284}
285
286Preprocessor::macro_iterator
287Preprocessor::macro_end(bool IncludeExternalMacros) const {
288  if (IncludeExternalMacros && ExternalSource &&
289      !ReadMacrosFromExternalSource) {
290    ReadMacrosFromExternalSource = true;
291    ExternalSource->ReadDefinedMacros();
292  }
293
294  return Macros.end();
295}
296
297/// \brief Compares macro tokens with a specified token value sequence.
298static bool MacroDefinitionEquals(const MacroInfo *MI,
299                                  ArrayRef<TokenValue> Tokens) {
300  return Tokens.size() == MI->getNumTokens() &&
301      std::equal(Tokens.begin(), Tokens.end(), MI->tokens_begin());
302}
303
304StringRef Preprocessor::getLastMacroWithSpelling(
305                                    SourceLocation Loc,
306                                    ArrayRef<TokenValue> Tokens) const {
307  SourceLocation BestLocation;
308  StringRef BestSpelling;
309  for (Preprocessor::macro_iterator I = macro_begin(), E = macro_end();
310       I != E; ++I) {
311    if (!I->second->getMacroInfo()->isObjectLike())
312      continue;
313    const MacroDirective::DefInfo
314      Def = I->second->findDirectiveAtLoc(Loc, SourceMgr);
315    if (!Def)
316      continue;
317    if (!MacroDefinitionEquals(Def.getMacroInfo(), Tokens))
318      continue;
319    SourceLocation Location = Def.getLocation();
320    // Choose the macro defined latest.
321    if (BestLocation.isInvalid() ||
322        (Location.isValid() &&
323         SourceMgr.isBeforeInTranslationUnit(BestLocation, Location))) {
324      BestLocation = Location;
325      BestSpelling = I->first->getName();
326    }
327  }
328  return BestSpelling;
329}
330
331void Preprocessor::recomputeCurLexerKind() {
332  if (CurLexer)
333    CurLexerKind = CLK_Lexer;
334  else if (CurPTHLexer)
335    CurLexerKind = CLK_PTHLexer;
336  else if (CurTokenLexer)
337    CurLexerKind = CLK_TokenLexer;
338  else
339    CurLexerKind = CLK_CachingLexer;
340}
341
342bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
343                                          unsigned CompleteLine,
344                                          unsigned CompleteColumn) {
345  assert(File);
346  assert(CompleteLine && CompleteColumn && "Starts from 1:1");
347  assert(!CodeCompletionFile && "Already set");
348
349  using llvm::MemoryBuffer;
350
351  // Load the actual file's contents.
352  bool Invalid = false;
353  const MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File, &Invalid);
354  if (Invalid)
355    return true;
356
357  // Find the byte position of the truncation point.
358  const char *Position = Buffer->getBufferStart();
359  for (unsigned Line = 1; Line < CompleteLine; ++Line) {
360    for (; *Position; ++Position) {
361      if (*Position != '\r' && *Position != '\n')
362        continue;
363
364      // Eat \r\n or \n\r as a single line.
365      if ((Position[1] == '\r' || Position[1] == '\n') &&
366          Position[0] != Position[1])
367        ++Position;
368      ++Position;
369      break;
370    }
371  }
372
373  Position += CompleteColumn - 1;
374
375  // Insert '\0' at the code-completion point.
376  if (Position < Buffer->getBufferEnd()) {
377    CodeCompletionFile = File;
378    CodeCompletionOffset = Position - Buffer->getBufferStart();
379
380    MemoryBuffer *NewBuffer =
381        MemoryBuffer::getNewUninitMemBuffer(Buffer->getBufferSize() + 1,
382                                            Buffer->getBufferIdentifier());
383    char *NewBuf = const_cast<char*>(NewBuffer->getBufferStart());
384    char *NewPos = std::copy(Buffer->getBufferStart(), Position, NewBuf);
385    *NewPos = '\0';
386    std::copy(Position, Buffer->getBufferEnd(), NewPos+1);
387    SourceMgr.overrideFileContents(File, NewBuffer);
388  }
389
390  return false;
391}
392
393void Preprocessor::CodeCompleteNaturalLanguage() {
394  if (CodeComplete)
395    CodeComplete->CodeCompleteNaturalLanguage();
396  setCodeCompletionReached();
397}
398
399/// getSpelling - This method is used to get the spelling of a token into a
400/// SmallVector. Note that the returned StringRef may not point to the
401/// supplied buffer if a copy can be avoided.
402StringRef Preprocessor::getSpelling(const Token &Tok,
403                                          SmallVectorImpl<char> &Buffer,
404                                          bool *Invalid) const {
405  // NOTE: this has to be checked *before* testing for an IdentifierInfo.
406  if (Tok.isNot(tok::raw_identifier) && !Tok.hasUCN()) {
407    // Try the fast path.
408    if (const IdentifierInfo *II = Tok.getIdentifierInfo())
409      return II->getName();
410  }
411
412  // Resize the buffer if we need to copy into it.
413  if (Tok.needsCleaning())
414    Buffer.resize(Tok.getLength());
415
416  const char *Ptr = Buffer.data();
417  unsigned Len = getSpelling(Tok, Ptr, Invalid);
418  return StringRef(Ptr, Len);
419}
420
421/// CreateString - Plop the specified string into a scratch buffer and return a
422/// location for it.  If specified, the source location provides a source
423/// location for the token.
424void Preprocessor::CreateString(StringRef Str, Token &Tok,
425                                SourceLocation ExpansionLocStart,
426                                SourceLocation ExpansionLocEnd) {
427  Tok.setLength(Str.size());
428
429  const char *DestPtr;
430  SourceLocation Loc = ScratchBuf->getToken(Str.data(), Str.size(), DestPtr);
431
432  if (ExpansionLocStart.isValid())
433    Loc = SourceMgr.createExpansionLoc(Loc, ExpansionLocStart,
434                                       ExpansionLocEnd, Str.size());
435  Tok.setLocation(Loc);
436
437  // If this is a raw identifier or a literal token, set the pointer data.
438  if (Tok.is(tok::raw_identifier))
439    Tok.setRawIdentifierData(DestPtr);
440  else if (Tok.isLiteral())
441    Tok.setLiteralData(DestPtr);
442}
443
444Module *Preprocessor::getCurrentModule() {
445  if (getLangOpts().CurrentModule.empty())
446    return 0;
447
448  return getHeaderSearchInfo().lookupModule(getLangOpts().CurrentModule);
449}
450
451//===----------------------------------------------------------------------===//
452// Preprocessor Initialization Methods
453//===----------------------------------------------------------------------===//
454
455
456/// EnterMainSourceFile - Enter the specified FileID as the main source file,
457/// which implicitly adds the builtin defines etc.
458void Preprocessor::EnterMainSourceFile() {
459  // We do not allow the preprocessor to reenter the main file.  Doing so will
460  // cause FileID's to accumulate information from both runs (e.g. #line
461  // information) and predefined macros aren't guaranteed to be set properly.
462  assert(NumEnteredSourceFiles == 0 && "Cannot reenter the main file!");
463  FileID MainFileID = SourceMgr.getMainFileID();
464
465  // If MainFileID is loaded it means we loaded an AST file, no need to enter
466  // a main file.
467  if (!SourceMgr.isLoadedFileID(MainFileID)) {
468    // Enter the main file source buffer.
469    EnterSourceFile(MainFileID, 0, SourceLocation());
470
471    // If we've been asked to skip bytes in the main file (e.g., as part of a
472    // precompiled preamble), do so now.
473    if (SkipMainFilePreamble.first > 0)
474      CurLexer->SkipBytes(SkipMainFilePreamble.first,
475                          SkipMainFilePreamble.second);
476
477    // Tell the header info that the main file was entered.  If the file is later
478    // #imported, it won't be re-entered.
479    if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))
480      HeaderInfo.IncrementIncludeCount(FE);
481  }
482
483  // Preprocess Predefines to populate the initial preprocessor state.
484  llvm::MemoryBuffer *SB =
485    llvm::MemoryBuffer::getMemBufferCopy(Predefines, "<built-in>");
486  assert(SB && "Cannot create predefined source buffer");
487  FileID FID = SourceMgr.createFileIDForMemBuffer(SB);
488  assert(!FID.isInvalid() && "Could not create FileID for predefines?");
489  setPredefinesFileID(FID);
490
491  // Start parsing the predefines.
492  EnterSourceFile(FID, 0, SourceLocation());
493}
494
495void Preprocessor::EndSourceFile() {
496  // Notify the client that we reached the end of the source file.
497  if (Callbacks)
498    Callbacks->EndOfMainFile();
499}
500
501//===----------------------------------------------------------------------===//
502// Lexer Event Handling.
503//===----------------------------------------------------------------------===//
504
505static void appendCodePoint(unsigned Codepoint,
506                            llvm::SmallVectorImpl<char> &Str) {
507  char ResultBuf[4];
508  char *ResultPtr = ResultBuf;
509  bool Res = llvm::ConvertCodePointToUTF8(Codepoint, ResultPtr);
510  (void)Res;
511  assert(Res && "Unexpected conversion failure");
512  Str.append(ResultBuf, ResultPtr);
513}
514
515static void expandUCNs(SmallVectorImpl<char> &Buf, StringRef Input) {
516  for (StringRef::iterator I = Input.begin(), E = Input.end(); I != E; ++I) {
517    if (*I != '\\') {
518      Buf.push_back(*I);
519      continue;
520    }
521
522    ++I;
523    assert(*I == 'u' || *I == 'U');
524
525    unsigned NumHexDigits;
526    if (*I == 'u')
527      NumHexDigits = 4;
528    else
529      NumHexDigits = 8;
530
531    assert(I + NumHexDigits <= E);
532
533    uint32_t CodePoint = 0;
534    for (++I; NumHexDigits != 0; ++I, --NumHexDigits) {
535      unsigned Value = llvm::hexDigitValue(*I);
536      assert(Value != -1U);
537
538      CodePoint <<= 4;
539      CodePoint += Value;
540    }
541
542    appendCodePoint(CodePoint, Buf);
543    --I;
544  }
545}
546
547/// LookUpIdentifierInfo - Given a tok::raw_identifier token, look up the
548/// identifier information for the token and install it into the token,
549/// updating the token kind accordingly.
550IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier) const {
551  assert(Identifier.getRawIdentifierData() != 0 && "No raw identifier data!");
552
553  // Look up this token, see if it is a macro, or if it is a language keyword.
554  IdentifierInfo *II;
555  if (!Identifier.needsCleaning() && !Identifier.hasUCN()) {
556    // No cleaning needed, just use the characters from the lexed buffer.
557    II = getIdentifierInfo(StringRef(Identifier.getRawIdentifierData(),
558                                     Identifier.getLength()));
559  } else {
560    // Cleaning needed, alloca a buffer, clean into it, then use the buffer.
561    SmallString<64> IdentifierBuffer;
562    StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer);
563
564    if (Identifier.hasUCN()) {
565      SmallString<64> UCNIdentifierBuffer;
566      expandUCNs(UCNIdentifierBuffer, CleanedStr);
567      II = getIdentifierInfo(UCNIdentifierBuffer);
568    } else {
569      II = getIdentifierInfo(CleanedStr);
570    }
571  }
572
573  // Update the token info (identifier info and appropriate token kind).
574  Identifier.setIdentifierInfo(II);
575  Identifier.setKind(II->getTokenID());
576
577  return II;
578}
579
580void Preprocessor::SetPoisonReason(IdentifierInfo *II, unsigned DiagID) {
581  PoisonReasons[II] = DiagID;
582}
583
584void Preprocessor::PoisonSEHIdentifiers(bool Poison) {
585  assert(Ident__exception_code && Ident__exception_info);
586  assert(Ident___exception_code && Ident___exception_info);
587  Ident__exception_code->setIsPoisoned(Poison);
588  Ident___exception_code->setIsPoisoned(Poison);
589  Ident_GetExceptionCode->setIsPoisoned(Poison);
590  Ident__exception_info->setIsPoisoned(Poison);
591  Ident___exception_info->setIsPoisoned(Poison);
592  Ident_GetExceptionInfo->setIsPoisoned(Poison);
593  Ident__abnormal_termination->setIsPoisoned(Poison);
594  Ident___abnormal_termination->setIsPoisoned(Poison);
595  Ident_AbnormalTermination->setIsPoisoned(Poison);
596}
597
598void Preprocessor::HandlePoisonedIdentifier(Token & Identifier) {
599  assert(Identifier.getIdentifierInfo() &&
600         "Can't handle identifiers without identifier info!");
601  llvm::DenseMap<IdentifierInfo*,unsigned>::const_iterator it =
602    PoisonReasons.find(Identifier.getIdentifierInfo());
603  if(it == PoisonReasons.end())
604    Diag(Identifier, diag::err_pp_used_poisoned_id);
605  else
606    Diag(Identifier,it->second) << Identifier.getIdentifierInfo();
607}
608
609/// HandleIdentifier - This callback is invoked when the lexer reads an
610/// identifier.  This callback looks up the identifier in the map and/or
611/// potentially macro expands it or turns it into a named token (like 'for').
612///
613/// Note that callers of this method are guarded by checking the
614/// IdentifierInfo's 'isHandleIdentifierCase' bit.  If this method changes, the
615/// IdentifierInfo methods that compute these properties will need to change to
616/// match.
617void Preprocessor::HandleIdentifier(Token &Identifier) {
618  assert(Identifier.getIdentifierInfo() &&
619         "Can't handle identifiers without identifier info!");
620
621  IdentifierInfo &II = *Identifier.getIdentifierInfo();
622
623  // If the information about this identifier is out of date, update it from
624  // the external source.
625  // We have to treat __VA_ARGS__ in a special way, since it gets
626  // serialized with isPoisoned = true, but our preprocessor may have
627  // unpoisoned it if we're defining a C99 macro.
628  if (II.isOutOfDate()) {
629    bool CurrentIsPoisoned = false;
630    if (&II == Ident__VA_ARGS__)
631      CurrentIsPoisoned = Ident__VA_ARGS__->isPoisoned();
632
633    ExternalSource->updateOutOfDateIdentifier(II);
634    Identifier.setKind(II.getTokenID());
635
636    if (&II == Ident__VA_ARGS__)
637      II.setIsPoisoned(CurrentIsPoisoned);
638  }
639
640  // If this identifier was poisoned, and if it was not produced from a macro
641  // expansion, emit an error.
642  if (II.isPoisoned() && CurPPLexer) {
643    HandlePoisonedIdentifier(Identifier);
644  }
645
646  // If this is a macro to be expanded, do it.
647  if (MacroDirective *MD = getMacroDirective(&II)) {
648    MacroInfo *MI = MD->getMacroInfo();
649    if (!DisableMacroExpansion) {
650      if (!Identifier.isExpandDisabled() && MI->isEnabled()) {
651        if (!HandleMacroExpandedIdentifier(Identifier, MD))
652          return;
653      } else {
654        // C99 6.10.3.4p2 says that a disabled macro may never again be
655        // expanded, even if it's in a context where it could be expanded in the
656        // future.
657        Identifier.setFlag(Token::DisableExpand);
658        if (MI->isObjectLike() || isNextPPTokenLParen())
659          Diag(Identifier, diag::pp_disabled_macro_expansion);
660      }
661    }
662  }
663
664  // If this identifier is a keyword in C++11, produce a warning. Don't warn if
665  // we're not considering macro expansion, since this identifier might be the
666  // name of a macro.
667  // FIXME: This warning is disabled in cases where it shouldn't be, like
668  //   "#define constexpr constexpr", "int constexpr;"
669  if (II.isCXX11CompatKeyword() & !DisableMacroExpansion) {
670    Diag(Identifier, diag::warn_cxx11_keyword) << II.getName();
671    // Don't diagnose this keyword again in this translation unit.
672    II.setIsCXX11CompatKeyword(false);
673  }
674
675  // C++ 2.11p2: If this is an alternative representation of a C++ operator,
676  // then we act as if it is the actual operator and not the textual
677  // representation of it.
678  if (II.isCPlusPlusOperatorKeyword())
679    Identifier.setIdentifierInfo(0);
680
681  // If this is an extension token, diagnose its use.
682  // We avoid diagnosing tokens that originate from macro definitions.
683  // FIXME: This warning is disabled in cases where it shouldn't be,
684  // like "#define TY typeof", "TY(1) x".
685  if (II.isExtensionToken() && !DisableMacroExpansion)
686    Diag(Identifier, diag::ext_token_used);
687
688  // If this is the 'import' contextual keyword, note
689  // that the next token indicates a module name.
690  //
691  // Note that we do not treat 'import' as a contextual
692  // keyword when we're in a caching lexer, because caching lexers only get
693  // used in contexts where import declarations are disallowed.
694  if (II.isModulesImport() && !InMacroArgs && !DisableMacroExpansion &&
695      getLangOpts().Modules && CurLexerKind != CLK_CachingLexer) {
696    ModuleImportLoc = Identifier.getLocation();
697    ModuleImportPath.clear();
698    ModuleImportExpectsIdentifier = true;
699    CurLexerKind = CLK_LexAfterModuleImport;
700  }
701}
702
703/// \brief Lex a token following the 'import' contextual keyword.
704///
705void Preprocessor::LexAfterModuleImport(Token &Result) {
706  // Figure out what kind of lexer we actually have.
707  recomputeCurLexerKind();
708
709  // Lex the next token.
710  Lex(Result);
711
712  // The token sequence
713  //
714  //   import identifier (. identifier)*
715  //
716  // indicates a module import directive. We already saw the 'import'
717  // contextual keyword, so now we're looking for the identifiers.
718  if (ModuleImportExpectsIdentifier && Result.getKind() == tok::identifier) {
719    // We expected to see an identifier here, and we did; continue handling
720    // identifiers.
721    ModuleImportPath.push_back(std::make_pair(Result.getIdentifierInfo(),
722                                              Result.getLocation()));
723    ModuleImportExpectsIdentifier = false;
724    CurLexerKind = CLK_LexAfterModuleImport;
725    return;
726  }
727
728  // If we're expecting a '.' or a ';', and we got a '.', then wait until we
729  // see the next identifier.
730  if (!ModuleImportExpectsIdentifier && Result.getKind() == tok::period) {
731    ModuleImportExpectsIdentifier = true;
732    CurLexerKind = CLK_LexAfterModuleImport;
733    return;
734  }
735
736  // If we have a non-empty module path, load the named module.
737  if (!ModuleImportPath.empty() && getLangOpts().Modules) {
738    Module *Imported = TheModuleLoader.loadModule(ModuleImportLoc,
739                                                  ModuleImportPath,
740                                                  Module::MacrosVisible,
741                                                  /*IsIncludeDirective=*/false);
742    if (Callbacks)
743      Callbacks->moduleImport(ModuleImportLoc, ModuleImportPath, Imported);
744  }
745}
746
747bool Preprocessor::FinishLexStringLiteral(Token &Result, std::string &String,
748                                          const char *DiagnosticTag,
749                                          bool AllowMacroExpansion) {
750  // We need at least one string literal.
751  if (Result.isNot(tok::string_literal)) {
752    Diag(Result, diag::err_expected_string_literal)
753      << /*Source='in...'*/0 << DiagnosticTag;
754    return false;
755  }
756
757  // Lex string literal tokens, optionally with macro expansion.
758  SmallVector<Token, 4> StrToks;
759  do {
760    StrToks.push_back(Result);
761
762    if (Result.hasUDSuffix())
763      Diag(Result, diag::err_invalid_string_udl);
764
765    if (AllowMacroExpansion)
766      Lex(Result);
767    else
768      LexUnexpandedToken(Result);
769  } while (Result.is(tok::string_literal));
770
771  // Concatenate and parse the strings.
772  StringLiteralParser Literal(&StrToks[0], StrToks.size(), *this);
773  assert(Literal.isAscii() && "Didn't allow wide strings in");
774
775  if (Literal.hadError)
776    return false;
777
778  if (Literal.Pascal) {
779    Diag(StrToks[0].getLocation(), diag::err_expected_string_literal)
780      << /*Source='in...'*/0 << DiagnosticTag;
781    return false;
782  }
783
784  String = Literal.GetString();
785  return true;
786}
787
788void Preprocessor::addCommentHandler(CommentHandler *Handler) {
789  assert(Handler && "NULL comment handler");
790  assert(std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler) ==
791         CommentHandlers.end() && "Comment handler already registered");
792  CommentHandlers.push_back(Handler);
793}
794
795void Preprocessor::removeCommentHandler(CommentHandler *Handler) {
796  std::vector<CommentHandler *>::iterator Pos
797  = std::find(CommentHandlers.begin(), CommentHandlers.end(), Handler);
798  assert(Pos != CommentHandlers.end() && "Comment handler not registered");
799  CommentHandlers.erase(Pos);
800}
801
802bool Preprocessor::HandleComment(Token &result, SourceRange Comment) {
803  bool AnyPendingTokens = false;
804  for (std::vector<CommentHandler *>::iterator H = CommentHandlers.begin(),
805       HEnd = CommentHandlers.end();
806       H != HEnd; ++H) {
807    if ((*H)->HandleComment(*this, Comment))
808      AnyPendingTokens = true;
809  }
810  if (!AnyPendingTokens || getCommentRetentionState())
811    return false;
812  Lex(result);
813  return true;
814}
815
816ModuleLoader::~ModuleLoader() { }
817
818CommentHandler::~CommentHandler() { }
819
820CodeCompletionHandler::~CodeCompletionHandler() { }
821
822void Preprocessor::createPreprocessingRecord() {
823  if (Record)
824    return;
825
826  Record = new PreprocessingRecord(getSourceManager());
827  addPPCallbacks(Record);
828}
829