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comparison clang/lib/Lex/Preprocessor.cpp @ 150:1d019706d866

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author anatofuz
date Thu, 13 Feb 2020 15:10:13 +0900
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147:c2174574ed3a 150:1d019706d866
1 //===- Preprocessor.cpp - C Language Family Preprocessor Implementation ---===//
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 //===----------------------------------------------------------------------===//
8 //
9 // This file implements the Preprocessor interface.
10 //
11 //===----------------------------------------------------------------------===//
12 //
13 // Options to support:
14 // -H - Print the name of each header file used.
15 // -d[DNI] - Dump various things.
16 // -fworking-directory - #line's with preprocessor's working dir.
17 // -fpreprocessed
18 // -dependency-file,-M,-MM,-MF,-MG,-MP,-MT,-MQ,-MD,-MMD
19 // -W*
20 // -w
21 //
22 // Messages to emit:
23 // "Multiple include guards may be useful for:\n"
24 //
25 //===----------------------------------------------------------------------===//
26
27 #include "clang/Lex/Preprocessor.h"
28 #include "clang/Basic/Builtins.h"
29 #include "clang/Basic/FileManager.h"
30 #include "clang/Basic/FileSystemStatCache.h"
31 #include "clang/Basic/IdentifierTable.h"
32 #include "clang/Basic/LLVM.h"
33 #include "clang/Basic/LangOptions.h"
34 #include "clang/Basic/Module.h"
35 #include "clang/Basic/SourceLocation.h"
36 #include "clang/Basic/SourceManager.h"
37 #include "clang/Basic/TargetInfo.h"
38 #include "clang/Lex/CodeCompletionHandler.h"
39 #include "clang/Lex/ExternalPreprocessorSource.h"
40 #include "clang/Lex/HeaderSearch.h"
41 #include "clang/Lex/LexDiagnostic.h"
42 #include "clang/Lex/Lexer.h"
43 #include "clang/Lex/LiteralSupport.h"
44 #include "clang/Lex/MacroArgs.h"
45 #include "clang/Lex/MacroInfo.h"
46 #include "clang/Lex/ModuleLoader.h"
47 #include "clang/Lex/Pragma.h"
48 #include "clang/Lex/PreprocessingRecord.h"
49 #include "clang/Lex/PreprocessorLexer.h"
50 #include "clang/Lex/PreprocessorOptions.h"
51 #include "clang/Lex/ScratchBuffer.h"
52 #include "clang/Lex/Token.h"
53 #include "clang/Lex/TokenLexer.h"
54 #include "llvm/ADT/APInt.h"
55 #include "llvm/ADT/ArrayRef.h"
56 #include "llvm/ADT/DenseMap.h"
57 #include "llvm/ADT/STLExtras.h"
58 #include "llvm/ADT/SmallString.h"
59 #include "llvm/ADT/SmallVector.h"
60 #include "llvm/ADT/StringRef.h"
61 #include "llvm/ADT/StringSwitch.h"
62 #include "llvm/Support/Capacity.h"
63 #include "llvm/Support/ErrorHandling.h"
64 #include "llvm/Support/MemoryBuffer.h"
65 #include "llvm/Support/raw_ostream.h"
66 #include <algorithm>
67 #include <cassert>
68 #include <memory>
69 #include <string>
70 #include <utility>
71 #include <vector>
72
73 using namespace clang;
74
75 LLVM_INSTANTIATE_REGISTRY(PragmaHandlerRegistry)
76
77 ExternalPreprocessorSource::~ExternalPreprocessorSource() = default;
78
79 Preprocessor::Preprocessor(std::shared_ptr<PreprocessorOptions> PPOpts,
80 DiagnosticsEngine &diags, LangOptions &opts,
81 SourceManager &SM, HeaderSearch &Headers,
82 ModuleLoader &TheModuleLoader,
83 IdentifierInfoLookup *IILookup, bool OwnsHeaders,
84 TranslationUnitKind TUKind)
85 : PPOpts(std::move(PPOpts)), Diags(&diags), LangOpts(opts),
86 FileMgr(Headers.getFileMgr()), SourceMgr(SM),
87 ScratchBuf(new ScratchBuffer(SourceMgr)), HeaderInfo(Headers),
88 TheModuleLoader(TheModuleLoader), ExternalSource(nullptr),
89 // As the language options may have not been loaded yet (when
90 // deserializing an ASTUnit), adding keywords to the identifier table is
91 // deferred to Preprocessor::Initialize().
92 Identifiers(IILookup), PragmaHandlers(new PragmaNamespace(StringRef())),
93 TUKind(TUKind), SkipMainFilePreamble(0, true),
94 CurSubmoduleState(&NullSubmoduleState) {
95 OwnsHeaderSearch = OwnsHeaders;
96
97 // Default to discarding comments.
98 KeepComments = false;
99 KeepMacroComments = false;
100 SuppressIncludeNotFoundError = false;
101
102 // Macro expansion is enabled.
103 DisableMacroExpansion = false;
104 MacroExpansionInDirectivesOverride = false;
105 InMacroArgs = false;
106 ArgMacro = nullptr;
107 InMacroArgPreExpansion = false;
108 NumCachedTokenLexers = 0;
109 PragmasEnabled = true;
110 ParsingIfOrElifDirective = false;
111 PreprocessedOutput = false;
112
113 // We haven't read anything from the external source.
114 ReadMacrosFromExternalSource = false;
115
116 BuiltinInfo = std::make_unique<Builtin::Context>();
117
118 // "Poison" __VA_ARGS__, __VA_OPT__ which can only appear in the expansion of
119 // a macro. They get unpoisoned where it is allowed.
120 (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned();
121 SetPoisonReason(Ident__VA_ARGS__,diag::ext_pp_bad_vaargs_use);
122 if (getLangOpts().CPlusPlus2a) {
123 (Ident__VA_OPT__ = getIdentifierInfo("__VA_OPT__"))->setIsPoisoned();
124 SetPoisonReason(Ident__VA_OPT__,diag::ext_pp_bad_vaopt_use);
125 } else {
126 Ident__VA_OPT__ = nullptr;
127 }
128
129 // Initialize the pragma handlers.
130 RegisterBuiltinPragmas();
131
132 // Initialize builtin macros like __LINE__ and friends.
133 RegisterBuiltinMacros();
134
135 if(LangOpts.Borland) {
136 Ident__exception_info = getIdentifierInfo("_exception_info");
137 Ident___exception_info = getIdentifierInfo("__exception_info");
138 Ident_GetExceptionInfo = getIdentifierInfo("GetExceptionInformation");
139 Ident__exception_code = getIdentifierInfo("_exception_code");
140 Ident___exception_code = getIdentifierInfo("__exception_code");
141 Ident_GetExceptionCode = getIdentifierInfo("GetExceptionCode");
142 Ident__abnormal_termination = getIdentifierInfo("_abnormal_termination");
143 Ident___abnormal_termination = getIdentifierInfo("__abnormal_termination");
144 Ident_AbnormalTermination = getIdentifierInfo("AbnormalTermination");
145 } else {
146 Ident__exception_info = Ident__exception_code = nullptr;
147 Ident__abnormal_termination = Ident___exception_info = nullptr;
148 Ident___exception_code = Ident___abnormal_termination = nullptr;
149 Ident_GetExceptionInfo = Ident_GetExceptionCode = nullptr;
150 Ident_AbnormalTermination = nullptr;
151 }
152
153 // If using a PCH where a #pragma hdrstop is expected, start skipping tokens.
154 if (usingPCHWithPragmaHdrStop())
155 SkippingUntilPragmaHdrStop = true;
156
157 // If using a PCH with a through header, start skipping tokens.
158 if (!this->PPOpts->PCHThroughHeader.empty() &&
159 !this->PPOpts->ImplicitPCHInclude.empty())
160 SkippingUntilPCHThroughHeader = true;
161
162 if (this->PPOpts->GeneratePreamble)
163 PreambleConditionalStack.startRecording();
164
165 ExcludedConditionalDirectiveSkipMappings =
166 this->PPOpts->ExcludedConditionalDirectiveSkipMappings;
167 if (ExcludedConditionalDirectiveSkipMappings)
168 ExcludedConditionalDirectiveSkipMappings->clear();
169
170 MaxTokens = LangOpts.MaxTokens;
171 }
172
173 Preprocessor::~Preprocessor() {
174 assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
175
176 IncludeMacroStack.clear();
177
178 // Destroy any macro definitions.
179 while (MacroInfoChain *I = MIChainHead) {
180 MIChainHead = I->Next;
181 I->~MacroInfoChain();
182 }
183
184 // Free any cached macro expanders.
185 // This populates MacroArgCache, so all TokenLexers need to be destroyed
186 // before the code below that frees up the MacroArgCache list.
187 std::fill(TokenLexerCache, TokenLexerCache + NumCachedTokenLexers, nullptr);
188 CurTokenLexer.reset();
189
190 // Free any cached MacroArgs.
191 for (MacroArgs *ArgList = MacroArgCache; ArgList;)
192 ArgList = ArgList->deallocate();
193
194 // Delete the header search info, if we own it.
195 if (OwnsHeaderSearch)
196 delete &HeaderInfo;
197 }
198
199 void Preprocessor::Initialize(const TargetInfo &Target,
200 const TargetInfo *AuxTarget) {
201 assert((!this->Target || this->Target == &Target) &&
202 "Invalid override of target information");
203 this->Target = &Target;
204
205 assert((!this->AuxTarget || this->AuxTarget == AuxTarget) &&
206 "Invalid override of aux target information.");
207 this->AuxTarget = AuxTarget;
208
209 // Initialize information about built-ins.
210 BuiltinInfo->InitializeTarget(Target, AuxTarget);
211 HeaderInfo.setTarget(Target);
212
213 // Populate the identifier table with info about keywords for the current language.
214 Identifiers.AddKeywords(LangOpts);
215 }
216
217 void Preprocessor::InitializeForModelFile() {
218 NumEnteredSourceFiles = 0;
219
220 // Reset pragmas
221 PragmaHandlersBackup = std::move(PragmaHandlers);
222 PragmaHandlers = std::make_unique<PragmaNamespace>(StringRef());
223 RegisterBuiltinPragmas();
224
225 // Reset PredefinesFileID
226 PredefinesFileID = FileID();
227 }
228
229 void Preprocessor::FinalizeForModelFile() {
230 NumEnteredSourceFiles = 1;
231
232 PragmaHandlers = std::move(PragmaHandlersBackup);
233 }
234
235 void Preprocessor::DumpToken(const Token &Tok, bool DumpFlags) const {
236 llvm::errs() << tok::getTokenName(Tok.getKind()) << " '"
237 << getSpelling(Tok) << "'";
238
239 if (!DumpFlags) return;
240
241 llvm::errs() << "\t";
242 if (Tok.isAtStartOfLine())
243 llvm::errs() << " [StartOfLine]";
244 if (Tok.hasLeadingSpace())
245 llvm::errs() << " [LeadingSpace]";
246 if (Tok.isExpandDisabled())
247 llvm::errs() << " [ExpandDisabled]";
248 if (Tok.needsCleaning()) {
249 const char *Start = SourceMgr.getCharacterData(Tok.getLocation());
250 llvm::errs() << " [UnClean='" << StringRef(Start, Tok.getLength())
251 << "']";
252 }
253
254 llvm::errs() << "\tLoc=<";
255 DumpLocation(Tok.getLocation());
256 llvm::errs() << ">";
257 }
258
259 void Preprocessor::DumpLocation(SourceLocation Loc) const {
260 Loc.print(llvm::errs(), SourceMgr);
261 }
262
263 void Preprocessor::DumpMacro(const MacroInfo &MI) const {
264 llvm::errs() << "MACRO: ";
265 for (unsigned i = 0, e = MI.getNumTokens(); i != e; ++i) {
266 DumpToken(MI.getReplacementToken(i));
267 llvm::errs() << " ";
268 }
269 llvm::errs() << "\n";
270 }
271
272 void Preprocessor::PrintStats() {
273 llvm::errs() << "\n*** Preprocessor Stats:\n";
274 llvm::errs() << NumDirectives << " directives found:\n";
275 llvm::errs() << " " << NumDefined << " #define.\n";
276 llvm::errs() << " " << NumUndefined << " #undef.\n";
277 llvm::errs() << " #include/#include_next/#import:\n";
278 llvm::errs() << " " << NumEnteredSourceFiles << " source files entered.\n";
279 llvm::errs() << " " << MaxIncludeStackDepth << " max include stack depth\n";
280 llvm::errs() << " " << NumIf << " #if/#ifndef/#ifdef.\n";
281 llvm::errs() << " " << NumElse << " #else/#elif.\n";
282 llvm::errs() << " " << NumEndif << " #endif.\n";
283 llvm::errs() << " " << NumPragma << " #pragma.\n";
284 llvm::errs() << NumSkipped << " #if/#ifndef#ifdef regions skipped\n";
285
286 llvm::errs() << NumMacroExpanded << "/" << NumFnMacroExpanded << "/"
287 << NumBuiltinMacroExpanded << " obj/fn/builtin macros expanded, "
288 << NumFastMacroExpanded << " on the fast path.\n";
289 llvm::errs() << (NumFastTokenPaste+NumTokenPaste)
290 << " token paste (##) operations performed, "
291 << NumFastTokenPaste << " on the fast path.\n";
292
293 llvm::errs() << "\nPreprocessor Memory: " << getTotalMemory() << "B total";
294
295 llvm::errs() << "\n BumpPtr: " << BP.getTotalMemory();
296 llvm::errs() << "\n Macro Expanded Tokens: "
297 << llvm::capacity_in_bytes(MacroExpandedTokens);
298 llvm::errs() << "\n Predefines Buffer: " << Predefines.capacity();
299 // FIXME: List information for all submodules.
300 llvm::errs() << "\n Macros: "
301 << llvm::capacity_in_bytes(CurSubmoduleState->Macros);
302 llvm::errs() << "\n #pragma push_macro Info: "
303 << llvm::capacity_in_bytes(PragmaPushMacroInfo);
304 llvm::errs() << "\n Poison Reasons: "
305 << llvm::capacity_in_bytes(PoisonReasons);
306 llvm::errs() << "\n Comment Handlers: "
307 << llvm::capacity_in_bytes(CommentHandlers) << "\n";
308 }
309
310 Preprocessor::macro_iterator
311 Preprocessor::macro_begin(bool IncludeExternalMacros) const {
312 if (IncludeExternalMacros && ExternalSource &&
313 !ReadMacrosFromExternalSource) {
314 ReadMacrosFromExternalSource = true;
315 ExternalSource->ReadDefinedMacros();
316 }
317
318 // Make sure we cover all macros in visible modules.
319 for (const ModuleMacro &Macro : ModuleMacros)
320 CurSubmoduleState->Macros.insert(std::make_pair(Macro.II, MacroState()));
321
322 return CurSubmoduleState->Macros.begin();
323 }
324
325 size_t Preprocessor::getTotalMemory() const {
326 return BP.getTotalMemory()
327 + llvm::capacity_in_bytes(MacroExpandedTokens)
328 + Predefines.capacity() /* Predefines buffer. */
329 // FIXME: Include sizes from all submodules, and include MacroInfo sizes,
330 // and ModuleMacros.
331 + llvm::capacity_in_bytes(CurSubmoduleState->Macros)
332 + llvm::capacity_in_bytes(PragmaPushMacroInfo)
333 + llvm::capacity_in_bytes(PoisonReasons)
334 + llvm::capacity_in_bytes(CommentHandlers);
335 }
336
337 Preprocessor::macro_iterator
338 Preprocessor::macro_end(bool IncludeExternalMacros) const {
339 if (IncludeExternalMacros && ExternalSource &&
340 !ReadMacrosFromExternalSource) {
341 ReadMacrosFromExternalSource = true;
342 ExternalSource->ReadDefinedMacros();
343 }
344
345 return CurSubmoduleState->Macros.end();
346 }
347
348 /// Compares macro tokens with a specified token value sequence.
349 static bool MacroDefinitionEquals(const MacroInfo *MI,
350 ArrayRef<TokenValue> Tokens) {
351 return Tokens.size() == MI->getNumTokens() &&
352 std::equal(Tokens.begin(), Tokens.end(), MI->tokens_begin());
353 }
354
355 StringRef Preprocessor::getLastMacroWithSpelling(
356 SourceLocation Loc,
357 ArrayRef<TokenValue> Tokens) const {
358 SourceLocation BestLocation;
359 StringRef BestSpelling;
360 for (Preprocessor::macro_iterator I = macro_begin(), E = macro_end();
361 I != E; ++I) {
362 const MacroDirective::DefInfo
363 Def = I->second.findDirectiveAtLoc(Loc, SourceMgr);
364 if (!Def || !Def.getMacroInfo())
365 continue;
366 if (!Def.getMacroInfo()->isObjectLike())
367 continue;
368 if (!MacroDefinitionEquals(Def.getMacroInfo(), Tokens))
369 continue;
370 SourceLocation Location = Def.getLocation();
371 // Choose the macro defined latest.
372 if (BestLocation.isInvalid() ||
373 (Location.isValid() &&
374 SourceMgr.isBeforeInTranslationUnit(BestLocation, Location))) {
375 BestLocation = Location;
376 BestSpelling = I->first->getName();
377 }
378 }
379 return BestSpelling;
380 }
381
382 void Preprocessor::recomputeCurLexerKind() {
383 if (CurLexer)
384 CurLexerKind = CLK_Lexer;
385 else if (CurTokenLexer)
386 CurLexerKind = CLK_TokenLexer;
387 else
388 CurLexerKind = CLK_CachingLexer;
389 }
390
391 bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
392 unsigned CompleteLine,
393 unsigned CompleteColumn) {
394 assert(File);
395 assert(CompleteLine && CompleteColumn && "Starts from 1:1");
396 assert(!CodeCompletionFile && "Already set");
397
398 using llvm::MemoryBuffer;
399
400 // Load the actual file's contents.
401 bool Invalid = false;
402 const MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File, &Invalid);
403 if (Invalid)
404 return true;
405
406 // Find the byte position of the truncation point.
407 const char *Position = Buffer->getBufferStart();
408 for (unsigned Line = 1; Line < CompleteLine; ++Line) {
409 for (; *Position; ++Position) {
410 if (*Position != '\r' && *Position != '\n')
411 continue;
412
413 // Eat \r\n or \n\r as a single line.
414 if ((Position[1] == '\r' || Position[1] == '\n') &&
415 Position[0] != Position[1])
416 ++Position;
417 ++Position;
418 break;
419 }
420 }
421
422 Position += CompleteColumn - 1;
423
424 // If pointing inside the preamble, adjust the position at the beginning of
425 // the file after the preamble.
426 if (SkipMainFilePreamble.first &&
427 SourceMgr.getFileEntryForID(SourceMgr.getMainFileID()) == File) {
428 if (Position - Buffer->getBufferStart() < SkipMainFilePreamble.first)
429 Position = Buffer->getBufferStart() + SkipMainFilePreamble.first;
430 }
431
432 if (Position > Buffer->getBufferEnd())
433 Position = Buffer->getBufferEnd();
434
435 CodeCompletionFile = File;
436 CodeCompletionOffset = Position - Buffer->getBufferStart();
437
438 auto NewBuffer = llvm::WritableMemoryBuffer::getNewUninitMemBuffer(
439 Buffer->getBufferSize() + 1, Buffer->getBufferIdentifier());
440 char *NewBuf = NewBuffer->getBufferStart();
441 char *NewPos = std::copy(Buffer->getBufferStart(), Position, NewBuf);
442 *NewPos = '\0';
443 std::copy(Position, Buffer->getBufferEnd(), NewPos+1);
444 SourceMgr.overrideFileContents(File, std::move(NewBuffer));
445
446 return false;
447 }
448
449 void Preprocessor::CodeCompleteIncludedFile(llvm::StringRef Dir,
450 bool IsAngled) {
451 if (CodeComplete)
452 CodeComplete->CodeCompleteIncludedFile(Dir, IsAngled);
453 setCodeCompletionReached();
454 }
455
456 void Preprocessor::CodeCompleteNaturalLanguage() {
457 if (CodeComplete)
458 CodeComplete->CodeCompleteNaturalLanguage();
459 setCodeCompletionReached();
460 }
461
462 /// getSpelling - This method is used to get the spelling of a token into a
463 /// SmallVector. Note that the returned StringRef may not point to the
464 /// supplied buffer if a copy can be avoided.
465 StringRef Preprocessor::getSpelling(const Token &Tok,
466 SmallVectorImpl<char> &Buffer,
467 bool *Invalid) const {
468 // NOTE: this has to be checked *before* testing for an IdentifierInfo.
469 if (Tok.isNot(tok::raw_identifier) && !Tok.hasUCN()) {
470 // Try the fast path.
471 if (const IdentifierInfo *II = Tok.getIdentifierInfo())
472 return II->getName();
473 }
474
475 // Resize the buffer if we need to copy into it.
476 if (Tok.needsCleaning())
477 Buffer.resize(Tok.getLength());
478
479 const char *Ptr = Buffer.data();
480 unsigned Len = getSpelling(Tok, Ptr, Invalid);
481 return StringRef(Ptr, Len);
482 }
483
484 /// CreateString - Plop the specified string into a scratch buffer and return a
485 /// location for it. If specified, the source location provides a source
486 /// location for the token.
487 void Preprocessor::CreateString(StringRef Str, Token &Tok,
488 SourceLocation ExpansionLocStart,
489 SourceLocation ExpansionLocEnd) {
490 Tok.setLength(Str.size());
491
492 const char *DestPtr;
493 SourceLocation Loc = ScratchBuf->getToken(Str.data(), Str.size(), DestPtr);
494
495 if (ExpansionLocStart.isValid())
496 Loc = SourceMgr.createExpansionLoc(Loc, ExpansionLocStart,
497 ExpansionLocEnd, Str.size());
498 Tok.setLocation(Loc);
499
500 // If this is a raw identifier or a literal token, set the pointer data.
501 if (Tok.is(tok::raw_identifier))
502 Tok.setRawIdentifierData(DestPtr);
503 else if (Tok.isLiteral())
504 Tok.setLiteralData(DestPtr);
505 }
506
507 SourceLocation Preprocessor::SplitToken(SourceLocation Loc, unsigned Length) {
508 auto &SM = getSourceManager();
509 SourceLocation SpellingLoc = SM.getSpellingLoc(Loc);
510 std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(SpellingLoc);
511 bool Invalid = false;
512 StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
513 if (Invalid)
514 return SourceLocation();
515
516 // FIXME: We could consider re-using spelling for tokens we see repeatedly.
517 const char *DestPtr;
518 SourceLocation Spelling =
519 ScratchBuf->getToken(Buffer.data() + LocInfo.second, Length, DestPtr);
520 return SM.createTokenSplitLoc(Spelling, Loc, Loc.getLocWithOffset(Length));
521 }
522
523 Module *Preprocessor::getCurrentModule() {
524 if (!getLangOpts().isCompilingModule())
525 return nullptr;
526
527 return getHeaderSearchInfo().lookupModule(getLangOpts().CurrentModule);
528 }
529
530 //===----------------------------------------------------------------------===//
531 // Preprocessor Initialization Methods
532 //===----------------------------------------------------------------------===//
533
534 /// EnterMainSourceFile - Enter the specified FileID as the main source file,
535 /// which implicitly adds the builtin defines etc.
536 void Preprocessor::EnterMainSourceFile() {
537 // We do not allow the preprocessor to reenter the main file. Doing so will
538 // cause FileID's to accumulate information from both runs (e.g. #line
539 // information) and predefined macros aren't guaranteed to be set properly.
540 assert(NumEnteredSourceFiles == 0 && "Cannot reenter the main file!");
541 FileID MainFileID = SourceMgr.getMainFileID();
542
543 // If MainFileID is loaded it means we loaded an AST file, no need to enter
544 // a main file.
545 if (!SourceMgr.isLoadedFileID(MainFileID)) {
546 // Enter the main file source buffer.
547 EnterSourceFile(MainFileID, nullptr, SourceLocation());
548
549 // If we've been asked to skip bytes in the main file (e.g., as part of a
550 // precompiled preamble), do so now.
551 if (SkipMainFilePreamble.first > 0)
552 CurLexer->SetByteOffset(SkipMainFilePreamble.first,
553 SkipMainFilePreamble.second);
554
555 // Tell the header info that the main file was entered. If the file is later
556 // #imported, it won't be re-entered.
557 if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))
558 HeaderInfo.IncrementIncludeCount(FE);
559 }
560
561 // Preprocess Predefines to populate the initial preprocessor state.
562 std::unique_ptr<llvm::MemoryBuffer> SB =
563 llvm::MemoryBuffer::getMemBufferCopy(Predefines, "<built-in>");
564 assert(SB && "Cannot create predefined source buffer");
565 FileID FID = SourceMgr.createFileID(std::move(SB));
566 assert(FID.isValid() && "Could not create FileID for predefines?");
567 setPredefinesFileID(FID);
568
569 // Start parsing the predefines.
570 EnterSourceFile(FID, nullptr, SourceLocation());
571
572 if (!PPOpts->PCHThroughHeader.empty()) {
573 // Lookup and save the FileID for the through header. If it isn't found
574 // in the search path, it's a fatal error.
575 const DirectoryLookup *CurDir;
576 Optional<FileEntryRef> File = LookupFile(
577 SourceLocation(), PPOpts->PCHThroughHeader,
578 /*isAngled=*/false, /*FromDir=*/nullptr, /*FromFile=*/nullptr, CurDir,
579 /*SearchPath=*/nullptr, /*RelativePath=*/nullptr,
580 /*SuggestedModule=*/nullptr, /*IsMapped=*/nullptr,
581 /*IsFrameworkFound=*/nullptr);
582 if (!File) {
583 Diag(SourceLocation(), diag::err_pp_through_header_not_found)
584 << PPOpts->PCHThroughHeader;
585 return;
586 }
587 setPCHThroughHeaderFileID(
588 SourceMgr.createFileID(*File, SourceLocation(), SrcMgr::C_User));
589 }
590
591 // Skip tokens from the Predefines and if needed the main file.
592 if ((usingPCHWithThroughHeader() && SkippingUntilPCHThroughHeader) ||
593 (usingPCHWithPragmaHdrStop() && SkippingUntilPragmaHdrStop))
594 SkipTokensWhileUsingPCH();
595 }
596
597 void Preprocessor::setPCHThroughHeaderFileID(FileID FID) {
598 assert(PCHThroughHeaderFileID.isInvalid() &&
599 "PCHThroughHeaderFileID already set!");
600 PCHThroughHeaderFileID = FID;
601 }
602
603 bool Preprocessor::isPCHThroughHeader(const FileEntry *FE) {
604 assert(PCHThroughHeaderFileID.isValid() &&
605 "Invalid PCH through header FileID");
606 return FE == SourceMgr.getFileEntryForID(PCHThroughHeaderFileID);
607 }
608
609 bool Preprocessor::creatingPCHWithThroughHeader() {
610 return TUKind == TU_Prefix && !PPOpts->PCHThroughHeader.empty() &&
611 PCHThroughHeaderFileID.isValid();
612 }
613
614 bool Preprocessor::usingPCHWithThroughHeader() {
615 return TUKind != TU_Prefix && !PPOpts->PCHThroughHeader.empty() &&
616 PCHThroughHeaderFileID.isValid();
617 }
618
619 bool Preprocessor::creatingPCHWithPragmaHdrStop() {
620 return TUKind == TU_Prefix && PPOpts->PCHWithHdrStop;
621 }
622
623 bool Preprocessor::usingPCHWithPragmaHdrStop() {
624 return TUKind != TU_Prefix && PPOpts->PCHWithHdrStop;
625 }
626
627 /// Skip tokens until after the #include of the through header or
628 /// until after a #pragma hdrstop is seen. Tokens in the predefines file
629 /// and the main file may be skipped. If the end of the predefines file
630 /// is reached, skipping continues into the main file. If the end of the
631 /// main file is reached, it's a fatal error.
632 void Preprocessor::SkipTokensWhileUsingPCH() {
633 bool ReachedMainFileEOF = false;
634 bool UsingPCHThroughHeader = SkippingUntilPCHThroughHeader;
635 bool UsingPragmaHdrStop = SkippingUntilPragmaHdrStop;
636 Token Tok;
637 while (true) {
638 bool InPredefines =
639 (CurLexer && CurLexer->getFileID() == getPredefinesFileID());
640 switch (CurLexerKind) {
641 case CLK_Lexer:
642 CurLexer->Lex(Tok);
643 break;
644 case CLK_TokenLexer:
645 CurTokenLexer->Lex(Tok);
646 break;
647 case CLK_CachingLexer:
648 CachingLex(Tok);
649 break;
650 case CLK_LexAfterModuleImport:
651 LexAfterModuleImport(Tok);
652 break;
653 }
654 if (Tok.is(tok::eof) && !InPredefines) {
655 ReachedMainFileEOF = true;
656 break;
657 }
658 if (UsingPCHThroughHeader && !SkippingUntilPCHThroughHeader)
659 break;
660 if (UsingPragmaHdrStop && !SkippingUntilPragmaHdrStop)
661 break;
662 }
663 if (ReachedMainFileEOF) {
664 if (UsingPCHThroughHeader)
665 Diag(SourceLocation(), diag::err_pp_through_header_not_seen)
666 << PPOpts->PCHThroughHeader << 1;
667 else if (!PPOpts->PCHWithHdrStopCreate)
668 Diag(SourceLocation(), diag::err_pp_pragma_hdrstop_not_seen);
669 }
670 }
671
672 void Preprocessor::replayPreambleConditionalStack() {
673 // Restore the conditional stack from the preamble, if there is one.
674 if (PreambleConditionalStack.isReplaying()) {
675 assert(CurPPLexer &&
676 "CurPPLexer is null when calling replayPreambleConditionalStack.");
677 CurPPLexer->setConditionalLevels(PreambleConditionalStack.getStack());
678 PreambleConditionalStack.doneReplaying();
679 if (PreambleConditionalStack.reachedEOFWhileSkipping())
680 SkipExcludedConditionalBlock(
681 PreambleConditionalStack.SkipInfo->HashTokenLoc,
682 PreambleConditionalStack.SkipInfo->IfTokenLoc,
683 PreambleConditionalStack.SkipInfo->FoundNonSkipPortion,
684 PreambleConditionalStack.SkipInfo->FoundElse,
685 PreambleConditionalStack.SkipInfo->ElseLoc);
686 }
687 }
688
689 void Preprocessor::EndSourceFile() {
690 // Notify the client that we reached the end of the source file.
691 if (Callbacks)
692 Callbacks->EndOfMainFile();
693 }
694
695 //===----------------------------------------------------------------------===//
696 // Lexer Event Handling.
697 //===----------------------------------------------------------------------===//
698
699 /// LookUpIdentifierInfo - Given a tok::raw_identifier token, look up the
700 /// identifier information for the token and install it into the token,
701 /// updating the token kind accordingly.
702 IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier) const {
703 assert(!Identifier.getRawIdentifier().empty() && "No raw identifier data!");
704
705 // Look up this token, see if it is a macro, or if it is a language keyword.
706 IdentifierInfo *II;
707 if (!Identifier.needsCleaning() && !Identifier.hasUCN()) {
708 // No cleaning needed, just use the characters from the lexed buffer.
709 II = getIdentifierInfo(Identifier.getRawIdentifier());
710 } else {
711 // Cleaning needed, alloca a buffer, clean into it, then use the buffer.
712 SmallString<64> IdentifierBuffer;
713 StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer);
714
715 if (Identifier.hasUCN()) {
716 SmallString<64> UCNIdentifierBuffer;
717 expandUCNs(UCNIdentifierBuffer, CleanedStr);
718 II = getIdentifierInfo(UCNIdentifierBuffer);
719 } else {
720 II = getIdentifierInfo(CleanedStr);
721 }
722 }
723
724 // Update the token info (identifier info and appropriate token kind).
725 Identifier.setIdentifierInfo(II);
726 if (getLangOpts().MSVCCompat && II->isCPlusPlusOperatorKeyword() &&
727 getSourceManager().isInSystemHeader(Identifier.getLocation()))
728 Identifier.setKind(tok::identifier);
729 else
730 Identifier.setKind(II->getTokenID());
731
732 return II;
733 }
734
735 void Preprocessor::SetPoisonReason(IdentifierInfo *II, unsigned DiagID) {
736 PoisonReasons[II] = DiagID;
737 }
738
739 void Preprocessor::PoisonSEHIdentifiers(bool Poison) {
740 assert(Ident__exception_code && Ident__exception_info);
741 assert(Ident___exception_code && Ident___exception_info);
742 Ident__exception_code->setIsPoisoned(Poison);
743 Ident___exception_code->setIsPoisoned(Poison);
744 Ident_GetExceptionCode->setIsPoisoned(Poison);
745 Ident__exception_info->setIsPoisoned(Poison);
746 Ident___exception_info->setIsPoisoned(Poison);
747 Ident_GetExceptionInfo->setIsPoisoned(Poison);
748 Ident__abnormal_termination->setIsPoisoned(Poison);
749 Ident___abnormal_termination->setIsPoisoned(Poison);
750 Ident_AbnormalTermination->setIsPoisoned(Poison);
751 }
752
753 void Preprocessor::HandlePoisonedIdentifier(Token & Identifier) {
754 assert(Identifier.getIdentifierInfo() &&
755 "Can't handle identifiers without identifier info!");
756 llvm::DenseMap<IdentifierInfo*,unsigned>::const_iterator it =
757 PoisonReasons.find(Identifier.getIdentifierInfo());
758 if(it == PoisonReasons.end())
759 Diag(Identifier, diag::err_pp_used_poisoned_id);
760 else
761 Diag(Identifier,it->second) << Identifier.getIdentifierInfo();
762 }
763
764 /// Returns a diagnostic message kind for reporting a future keyword as
765 /// appropriate for the identifier and specified language.
766 static diag::kind getFutureCompatDiagKind(const IdentifierInfo &II,
767 const LangOptions &LangOpts) {
768 assert(II.isFutureCompatKeyword() && "diagnostic should not be needed");
769
770 if (LangOpts.CPlusPlus)
771 return llvm::StringSwitch<diag::kind>(II.getName())
772 #define CXX11_KEYWORD(NAME, FLAGS) \
773 .Case(#NAME, diag::warn_cxx11_keyword)
774 #define CXX2A_KEYWORD(NAME, FLAGS) \
775 .Case(#NAME, diag::warn_cxx2a_keyword)
776 #include "clang/Basic/TokenKinds.def"
777 ;
778
779 llvm_unreachable(
780 "Keyword not known to come from a newer Standard or proposed Standard");
781 }
782
783 void Preprocessor::updateOutOfDateIdentifier(IdentifierInfo &II) const {
784 assert(II.isOutOfDate() && "not out of date");
785 getExternalSource()->updateOutOfDateIdentifier(II);
786 }
787
788 /// HandleIdentifier - This callback is invoked when the lexer reads an
789 /// identifier. This callback looks up the identifier in the map and/or
790 /// potentially macro expands it or turns it into a named token (like 'for').
791 ///
792 /// Note that callers of this method are guarded by checking the
793 /// IdentifierInfo's 'isHandleIdentifierCase' bit. If this method changes, the
794 /// IdentifierInfo methods that compute these properties will need to change to
795 /// match.
796 bool Preprocessor::HandleIdentifier(Token &Identifier) {
797 assert(Identifier.getIdentifierInfo() &&
798 "Can't handle identifiers without identifier info!");
799
800 IdentifierInfo &II = *Identifier.getIdentifierInfo();
801
802 // If the information about this identifier is out of date, update it from
803 // the external source.
804 // We have to treat __VA_ARGS__ in a special way, since it gets
805 // serialized with isPoisoned = true, but our preprocessor may have
806 // unpoisoned it if we're defining a C99 macro.
807 if (II.isOutOfDate()) {
808 bool CurrentIsPoisoned = false;
809 const bool IsSpecialVariadicMacro =
810 &II == Ident__VA_ARGS__ || &II == Ident__VA_OPT__;
811 if (IsSpecialVariadicMacro)
812 CurrentIsPoisoned = II.isPoisoned();
813
814 updateOutOfDateIdentifier(II);
815 Identifier.setKind(II.getTokenID());
816
817 if (IsSpecialVariadicMacro)
818 II.setIsPoisoned(CurrentIsPoisoned);
819 }
820
821 // If this identifier was poisoned, and if it was not produced from a macro
822 // expansion, emit an error.
823 if (II.isPoisoned() && CurPPLexer) {
824 HandlePoisonedIdentifier(Identifier);
825 }
826
827 // If this is a macro to be expanded, do it.
828 if (MacroDefinition MD = getMacroDefinition(&II)) {
829 auto *MI = MD.getMacroInfo();
830 assert(MI && "macro definition with no macro info?");
831 if (!DisableMacroExpansion) {
832 if (!Identifier.isExpandDisabled() && MI->isEnabled()) {
833 // C99 6.10.3p10: If the preprocessing token immediately after the
834 // macro name isn't a '(', this macro should not be expanded.
835 if (!MI->isFunctionLike() || isNextPPTokenLParen())
836 return HandleMacroExpandedIdentifier(Identifier, MD);
837 } else {
838 // C99 6.10.3.4p2 says that a disabled macro may never again be
839 // expanded, even if it's in a context where it could be expanded in the
840 // future.
841 Identifier.setFlag(Token::DisableExpand);
842 if (MI->isObjectLike() || isNextPPTokenLParen())
843 Diag(Identifier, diag::pp_disabled_macro_expansion);
844 }
845 }
846 }
847
848 // If this identifier is a keyword in a newer Standard or proposed Standard,
849 // produce a warning. Don't warn if we're not considering macro expansion,
850 // since this identifier might be the name of a macro.
851 // FIXME: This warning is disabled in cases where it shouldn't be, like
852 // "#define constexpr constexpr", "int constexpr;"
853 if (II.isFutureCompatKeyword() && !DisableMacroExpansion) {
854 Diag(Identifier, getFutureCompatDiagKind(II, getLangOpts()))
855 << II.getName();
856 // Don't diagnose this keyword again in this translation unit.
857 II.setIsFutureCompatKeyword(false);
858 }
859
860 // If this is an extension token, diagnose its use.
861 // We avoid diagnosing tokens that originate from macro definitions.
862 // FIXME: This warning is disabled in cases where it shouldn't be,
863 // like "#define TY typeof", "TY(1) x".
864 if (II.isExtensionToken() && !DisableMacroExpansion)
865 Diag(Identifier, diag::ext_token_used);
866
867 // If this is the 'import' contextual keyword following an '@', note
868 // that the next token indicates a module name.
869 //
870 // Note that we do not treat 'import' as a contextual
871 // keyword when we're in a caching lexer, because caching lexers only get
872 // used in contexts where import declarations are disallowed.
873 //
874 // Likewise if this is the C++ Modules TS import keyword.
875 if (((LastTokenWasAt && II.isModulesImport()) ||
876 Identifier.is(tok::kw_import)) &&
877 !InMacroArgs && !DisableMacroExpansion &&
878 (getLangOpts().Modules || getLangOpts().DebuggerSupport) &&
879 CurLexerKind != CLK_CachingLexer) {
880 ModuleImportLoc = Identifier.getLocation();
881 ModuleImportPath.clear();
882 ModuleImportExpectsIdentifier = true;
883 CurLexerKind = CLK_LexAfterModuleImport;
884 }
885 return true;
886 }
887
888 void Preprocessor::Lex(Token &Result) {
889 ++LexLevel;
890
891 // We loop here until a lex function returns a token; this avoids recursion.
892 bool ReturnedToken;
893 do {
894 switch (CurLexerKind) {
895 case CLK_Lexer:
896 ReturnedToken = CurLexer->Lex(Result);
897 break;
898 case CLK_TokenLexer:
899 ReturnedToken = CurTokenLexer->Lex(Result);
900 break;
901 case CLK_CachingLexer:
902 CachingLex(Result);
903 ReturnedToken = true;
904 break;
905 case CLK_LexAfterModuleImport:
906 ReturnedToken = LexAfterModuleImport(Result);
907 break;
908 }
909 } while (!ReturnedToken);
910
911 if (Result.is(tok::unknown) && TheModuleLoader.HadFatalFailure)
912 return;
913
914 if (Result.is(tok::code_completion) && Result.getIdentifierInfo()) {
915 // Remember the identifier before code completion token.
916 setCodeCompletionIdentifierInfo(Result.getIdentifierInfo());
917 setCodeCompletionTokenRange(Result.getLocation(), Result.getEndLoc());
918 // Set IdenfitierInfo to null to avoid confusing code that handles both
919 // identifiers and completion tokens.
920 Result.setIdentifierInfo(nullptr);
921 }
922
923 // Update ImportSeqState to track our position within a C++20 import-seq
924 // if this token is being produced as a result of phase 4 of translation.
925 if (getLangOpts().CPlusPlusModules && LexLevel == 1 &&
926 !Result.getFlag(Token::IsReinjected)) {
927 switch (Result.getKind()) {
928 case tok::l_paren: case tok::l_square: case tok::l_brace:
929 ImportSeqState.handleOpenBracket();
930 break;
931 case tok::r_paren: case tok::r_square:
932 ImportSeqState.handleCloseBracket();
933 break;
934 case tok::r_brace:
935 ImportSeqState.handleCloseBrace();
936 break;
937 case tok::semi:
938 ImportSeqState.handleSemi();
939 break;
940 case tok::header_name:
941 case tok::annot_header_unit:
942 ImportSeqState.handleHeaderName();
943 break;
944 case tok::kw_export:
945 ImportSeqState.handleExport();
946 break;
947 case tok::identifier:
948 if (Result.getIdentifierInfo()->isModulesImport()) {
949 ImportSeqState.handleImport();
950 if (ImportSeqState.afterImportSeq()) {
951 ModuleImportLoc = Result.getLocation();
952 ModuleImportPath.clear();
953 ModuleImportExpectsIdentifier = true;
954 CurLexerKind = CLK_LexAfterModuleImport;
955 }
956 break;
957 }
958 LLVM_FALLTHROUGH;
959 default:
960 ImportSeqState.handleMisc();
961 break;
962 }
963 }
964
965 LastTokenWasAt = Result.is(tok::at);
966 --LexLevel;
967
968 if (LexLevel == 0 && !Result.getFlag(Token::IsReinjected)) {
969 ++TokenCount;
970 if (OnToken)
971 OnToken(Result);
972 }
973 }
974
975 /// Lex a header-name token (including one formed from header-name-tokens if
976 /// \p AllowConcatenation is \c true).
977 ///
978 /// \param FilenameTok Filled in with the next token. On success, this will
979 /// be either a header_name token. On failure, it will be whatever other
980 /// token was found instead.
981 /// \param AllowMacroExpansion If \c true, allow the header name to be formed
982 /// by macro expansion (concatenating tokens as necessary if the first
983 /// token is a '<').
984 /// \return \c true if we reached EOD or EOF while looking for a > token in
985 /// a concatenated header name and diagnosed it. \c false otherwise.
986 bool Preprocessor::LexHeaderName(Token &FilenameTok, bool AllowMacroExpansion) {
987 // Lex using header-name tokenization rules if tokens are being lexed from
988 // a file. Just grab a token normally if we're in a macro expansion.
989 if (CurPPLexer)
990 CurPPLexer->LexIncludeFilename(FilenameTok);
991 else
992 Lex(FilenameTok);
993
994 // This could be a <foo/bar.h> file coming from a macro expansion. In this
995 // case, glue the tokens together into an angle_string_literal token.
996 SmallString<128> FilenameBuffer;
997 if (FilenameTok.is(tok::less) && AllowMacroExpansion) {
998 bool StartOfLine = FilenameTok.isAtStartOfLine();
999 bool LeadingSpace = FilenameTok.hasLeadingSpace();
1000 bool LeadingEmptyMacro = FilenameTok.hasLeadingEmptyMacro();
1001
1002 SourceLocation Start = FilenameTok.getLocation();
1003 SourceLocation End;
1004 FilenameBuffer.push_back('<');
1005
1006 // Consume tokens until we find a '>'.
1007 // FIXME: A header-name could be formed starting or ending with an
1008 // alternative token. It's not clear whether that's ill-formed in all
1009 // cases.
1010 while (FilenameTok.isNot(tok::greater)) {
1011 Lex(FilenameTok);
1012 if (FilenameTok.isOneOf(tok::eod, tok::eof)) {
1013 Diag(FilenameTok.getLocation(), diag::err_expected) << tok::greater;
1014 Diag(Start, diag::note_matching) << tok::less;
1015 return true;
1016 }
1017
1018 End = FilenameTok.getLocation();
1019
1020 // FIXME: Provide code completion for #includes.
1021 if (FilenameTok.is(tok::code_completion)) {
1022 setCodeCompletionReached();
1023 Lex(FilenameTok);
1024 continue;
1025 }
1026
1027 // Append the spelling of this token to the buffer. If there was a space
1028 // before it, add it now.
1029 if (FilenameTok.hasLeadingSpace())
1030 FilenameBuffer.push_back(' ');
1031
1032 // Get the spelling of the token, directly into FilenameBuffer if
1033 // possible.
1034 size_t PreAppendSize = FilenameBuffer.size();
1035 FilenameBuffer.resize(PreAppendSize + FilenameTok.getLength());
1036
1037 const char *BufPtr = &FilenameBuffer[PreAppendSize];
1038 unsigned ActualLen = getSpelling(FilenameTok, BufPtr);
1039
1040 // If the token was spelled somewhere else, copy it into FilenameBuffer.
1041 if (BufPtr != &FilenameBuffer[PreAppendSize])
1042 memcpy(&FilenameBuffer[PreAppendSize], BufPtr, ActualLen);
1043
1044 // Resize FilenameBuffer to the correct size.
1045 if (FilenameTok.getLength() != ActualLen)
1046 FilenameBuffer.resize(PreAppendSize + ActualLen);
1047 }
1048
1049 FilenameTok.startToken();
1050 FilenameTok.setKind(tok::header_name);
1051 FilenameTok.setFlagValue(Token::StartOfLine, StartOfLine);
1052 FilenameTok.setFlagValue(Token::LeadingSpace, LeadingSpace);
1053 FilenameTok.setFlagValue(Token::LeadingEmptyMacro, LeadingEmptyMacro);
1054 CreateString(FilenameBuffer, FilenameTok, Start, End);
1055 } else if (FilenameTok.is(tok::string_literal) && AllowMacroExpansion) {
1056 // Convert a string-literal token of the form " h-char-sequence "
1057 // (produced by macro expansion) into a header-name token.
1058 //
1059 // The rules for header-names don't quite match the rules for
1060 // string-literals, but all the places where they differ result in
1061 // undefined behavior, so we can and do treat them the same.
1062 //
1063 // A string-literal with a prefix or suffix is not translated into a
1064 // header-name. This could theoretically be observable via the C++20
1065 // context-sensitive header-name formation rules.
1066 StringRef Str = getSpelling(FilenameTok, FilenameBuffer);
1067 if (Str.size() >= 2 && Str.front() == '"' && Str.back() == '"')
1068 FilenameTok.setKind(tok::header_name);
1069 }
1070
1071 return false;
1072 }
1073
1074 /// Collect the tokens of a C++20 pp-import-suffix.
1075 void Preprocessor::CollectPpImportSuffix(SmallVectorImpl<Token> &Toks) {
1076 // FIXME: For error recovery, consider recognizing attribute syntax here
1077 // and terminating / diagnosing a missing semicolon if we find anything
1078 // else? (Can we leave that to the parser?)
1079 unsigned BracketDepth = 0;
1080 while (true) {
1081 Toks.emplace_back();
1082 Lex(Toks.back());
1083
1084 switch (Toks.back().getKind()) {
1085 case tok::l_paren: case tok::l_square: case tok::l_brace:
1086 ++BracketDepth;
1087 break;
1088
1089 case tok::r_paren: case tok::r_square: case tok::r_brace:
1090 if (BracketDepth == 0)
1091 return;
1092 --BracketDepth;
1093 break;
1094
1095 case tok::semi:
1096 if (BracketDepth == 0)
1097 return;
1098 break;
1099
1100 case tok::eof:
1101 return;
1102
1103 default:
1104 break;
1105 }
1106 }
1107 }
1108
1109
1110 /// Lex a token following the 'import' contextual keyword.
1111 ///
1112 /// pp-import: [C++20]
1113 /// import header-name pp-import-suffix[opt] ;
1114 /// import header-name-tokens pp-import-suffix[opt] ;
1115 /// [ObjC] @ import module-name ;
1116 /// [Clang] import module-name ;
1117 ///
1118 /// header-name-tokens:
1119 /// string-literal
1120 /// < [any sequence of preprocessing-tokens other than >] >
1121 ///
1122 /// module-name:
1123 /// module-name-qualifier[opt] identifier
1124 ///
1125 /// module-name-qualifier
1126 /// module-name-qualifier[opt] identifier .
1127 ///
1128 /// We respond to a pp-import by importing macros from the named module.
1129 bool Preprocessor::LexAfterModuleImport(Token &Result) {
1130 // Figure out what kind of lexer we actually have.
1131 recomputeCurLexerKind();
1132
1133 // Lex the next token. The header-name lexing rules are used at the start of
1134 // a pp-import.
1135 //
1136 // For now, we only support header-name imports in C++20 mode.
1137 // FIXME: Should we allow this in all language modes that support an import
1138 // declaration as an extension?
1139 if (ModuleImportPath.empty() && getLangOpts().CPlusPlusModules) {
1140 if (LexHeaderName(Result))
1141 return true;
1142 } else {
1143 Lex(Result);
1144 }
1145
1146 // Allocate a holding buffer for a sequence of tokens and introduce it into
1147 // the token stream.
1148 auto EnterTokens = [this](ArrayRef<Token> Toks) {
1149 auto ToksCopy = std::make_unique<Token[]>(Toks.size());
1150 std::copy(Toks.begin(), Toks.end(), ToksCopy.get());
1151 EnterTokenStream(std::move(ToksCopy), Toks.size(),
1152 /*DisableMacroExpansion*/ true, /*IsReinject*/ false);
1153 };
1154
1155 // Check for a header-name.
1156 SmallVector<Token, 32> Suffix;
1157 if (Result.is(tok::header_name)) {
1158 // Enter the header-name token into the token stream; a Lex action cannot
1159 // both return a token and cache tokens (doing so would corrupt the token
1160 // cache if the call to Lex comes from CachingLex / PeekAhead).
1161 Suffix.push_back(Result);
1162
1163 // Consume the pp-import-suffix and expand any macros in it now. We'll add
1164 // it back into the token stream later.
1165 CollectPpImportSuffix(Suffix);
1166 if (Suffix.back().isNot(tok::semi)) {
1167 // This is not a pp-import after all.
1168 EnterTokens(Suffix);
1169 return false;
1170 }
1171
1172 // C++2a [cpp.module]p1:
1173 // The ';' preprocessing-token terminating a pp-import shall not have
1174 // been produced by macro replacement.
1175 SourceLocation SemiLoc = Suffix.back().getLocation();
1176 if (SemiLoc.isMacroID())
1177 Diag(SemiLoc, diag::err_header_import_semi_in_macro);
1178
1179 // Reconstitute the import token.
1180 Token ImportTok;
1181 ImportTok.startToken();
1182 ImportTok.setKind(tok::kw_import);
1183 ImportTok.setLocation(ModuleImportLoc);
1184 ImportTok.setIdentifierInfo(getIdentifierInfo("import"));
1185 ImportTok.setLength(6);
1186
1187 auto Action = HandleHeaderIncludeOrImport(
1188 /*HashLoc*/ SourceLocation(), ImportTok, Suffix.front(), SemiLoc);
1189 switch (Action.Kind) {
1190 case ImportAction::None:
1191 break;
1192
1193 case ImportAction::ModuleBegin:
1194 // Let the parser know we're textually entering the module.
1195 Suffix.emplace_back();
1196 Suffix.back().startToken();
1197 Suffix.back().setKind(tok::annot_module_begin);
1198 Suffix.back().setLocation(SemiLoc);
1199 Suffix.back().setAnnotationEndLoc(SemiLoc);
1200 Suffix.back().setAnnotationValue(Action.ModuleForHeader);
1201 LLVM_FALLTHROUGH;
1202
1203 case ImportAction::ModuleImport:
1204 case ImportAction::SkippedModuleImport:
1205 // We chose to import (or textually enter) the file. Convert the
1206 // header-name token into a header unit annotation token.
1207 Suffix[0].setKind(tok::annot_header_unit);
1208 Suffix[0].setAnnotationEndLoc(Suffix[0].getLocation());
1209 Suffix[0].setAnnotationValue(Action.ModuleForHeader);
1210 // FIXME: Call the moduleImport callback?
1211 break;
1212 case ImportAction::Failure:
1213 assert(TheModuleLoader.HadFatalFailure &&
1214 "This should be an early exit only to a fatal error");
1215 Result.setKind(tok::eof);
1216 CurLexer->cutOffLexing();
1217 EnterTokens(Suffix);
1218 return true;
1219 }
1220
1221 EnterTokens(Suffix);
1222 return false;
1223 }
1224
1225 // The token sequence
1226 //
1227 // import identifier (. identifier)*
1228 //
1229 // indicates a module import directive. We already saw the 'import'
1230 // contextual keyword, so now we're looking for the identifiers.
1231 if (ModuleImportExpectsIdentifier && Result.getKind() == tok::identifier) {
1232 // We expected to see an identifier here, and we did; continue handling
1233 // identifiers.
1234 ModuleImportPath.push_back(std::make_pair(Result.getIdentifierInfo(),
1235 Result.getLocation()));
1236 ModuleImportExpectsIdentifier = false;
1237 CurLexerKind = CLK_LexAfterModuleImport;
1238 return true;
1239 }
1240
1241 // If we're expecting a '.' or a ';', and we got a '.', then wait until we
1242 // see the next identifier. (We can also see a '[[' that begins an
1243 // attribute-specifier-seq here under the C++ Modules TS.)
1244 if (!ModuleImportExpectsIdentifier && Result.getKind() == tok::period) {
1245 ModuleImportExpectsIdentifier = true;
1246 CurLexerKind = CLK_LexAfterModuleImport;
1247 return true;
1248 }
1249
1250 // If we didn't recognize a module name at all, this is not a (valid) import.
1251 if (ModuleImportPath.empty() || Result.is(tok::eof))
1252 return true;
1253
1254 // Consume the pp-import-suffix and expand any macros in it now, if we're not
1255 // at the semicolon already.
1256 SourceLocation SemiLoc = Result.getLocation();
1257 if (Result.isNot(tok::semi)) {
1258 Suffix.push_back(Result);
1259 CollectPpImportSuffix(Suffix);
1260 if (Suffix.back().isNot(tok::semi)) {
1261 // This is not an import after all.
1262 EnterTokens(Suffix);
1263 return false;
1264 }
1265 SemiLoc = Suffix.back().getLocation();
1266 }
1267
1268 // Under the Modules TS, the dot is just part of the module name, and not
1269 // a real hierarchy separator. Flatten such module names now.
1270 //
1271 // FIXME: Is this the right level to be performing this transformation?
1272 std::string FlatModuleName;
1273 if (getLangOpts().ModulesTS || getLangOpts().CPlusPlusModules) {
1274 for (auto &Piece : ModuleImportPath) {
1275 if (!FlatModuleName.empty())
1276 FlatModuleName += ".";
1277 FlatModuleName += Piece.first->getName();
1278 }
1279 SourceLocation FirstPathLoc = ModuleImportPath[0].second;
1280 ModuleImportPath.clear();
1281 ModuleImportPath.push_back(
1282 std::make_pair(getIdentifierInfo(FlatModuleName), FirstPathLoc));
1283 }
1284
1285 Module *Imported = nullptr;
1286 if (getLangOpts().Modules) {
1287 Imported = TheModuleLoader.loadModule(ModuleImportLoc,
1288 ModuleImportPath,
1289 Module::Hidden,
1290 /*IsInclusionDirective=*/false);
1291 if (Imported)
1292 makeModuleVisible(Imported, SemiLoc);
1293 }
1294 if (Callbacks)
1295 Callbacks->moduleImport(ModuleImportLoc, ModuleImportPath, Imported);
1296
1297 if (!Suffix.empty()) {
1298 EnterTokens(Suffix);
1299 return false;
1300 }
1301 return true;
1302 }
1303
1304 void Preprocessor::makeModuleVisible(Module *M, SourceLocation Loc) {
1305 CurSubmoduleState->VisibleModules.setVisible(
1306 M, Loc, [](Module *) {},
1307 [&](ArrayRef<Module *> Path, Module *Conflict, StringRef Message) {
1308 // FIXME: Include the path in the diagnostic.
1309 // FIXME: Include the import location for the conflicting module.
1310 Diag(ModuleImportLoc, diag::warn_module_conflict)
1311 << Path[0]->getFullModuleName()
1312 << Conflict->getFullModuleName()
1313 << Message;
1314 });
1315
1316 // Add this module to the imports list of the currently-built submodule.
1317 if (!BuildingSubmoduleStack.empty() && M != BuildingSubmoduleStack.back().M)
1318 BuildingSubmoduleStack.back().M->Imports.insert(M);
1319 }
1320
1321 bool Preprocessor::FinishLexStringLiteral(Token &Result, std::string &String,
1322 const char *DiagnosticTag,
1323 bool AllowMacroExpansion) {
1324 // We need at least one string literal.
1325 if (Result.isNot(tok::string_literal)) {
1326 Diag(Result, diag::err_expected_string_literal)
1327 << /*Source='in...'*/0 << DiagnosticTag;
1328 return false;
1329 }
1330
1331 // Lex string literal tokens, optionally with macro expansion.
1332 SmallVector<Token, 4> StrToks;
1333 do {
1334 StrToks.push_back(Result);
1335
1336 if (Result.hasUDSuffix())
1337 Diag(Result, diag::err_invalid_string_udl);
1338
1339 if (AllowMacroExpansion)
1340 Lex(Result);
1341 else
1342 LexUnexpandedToken(Result);
1343 } while (Result.is(tok::string_literal));
1344
1345 // Concatenate and parse the strings.
1346 StringLiteralParser Literal(StrToks, *this);
1347 assert(Literal.isAscii() && "Didn't allow wide strings in");
1348
1349 if (Literal.hadError)
1350 return false;
1351
1352 if (Literal.Pascal) {
1353 Diag(StrToks[0].getLocation(), diag::err_expected_string_literal)
1354 << /*Source='in...'*/0 << DiagnosticTag;
1355 return false;
1356 }
1357
1358 String = std::string(Literal.GetString());
1359 return true;
1360 }
1361
1362 bool Preprocessor::parseSimpleIntegerLiteral(Token &Tok, uint64_t &Value) {
1363 assert(Tok.is(tok::numeric_constant));
1364 SmallString<8> IntegerBuffer;
1365 bool NumberInvalid = false;
1366 StringRef Spelling = getSpelling(Tok, IntegerBuffer, &NumberInvalid);
1367 if (NumberInvalid)
1368 return false;
1369 NumericLiteralParser Literal(Spelling, Tok.getLocation(), *this);
1370 if (Literal.hadError || !Literal.isIntegerLiteral() || Literal.hasUDSuffix())
1371 return false;
1372 llvm::APInt APVal(64, 0);
1373 if (Literal.GetIntegerValue(APVal))
1374 return false;
1375 Lex(Tok);
1376 Value = APVal.getLimitedValue();
1377 return true;
1378 }
1379
1380 void Preprocessor::addCommentHandler(CommentHandler *Handler) {
1381 assert(Handler && "NULL comment handler");
1382 assert(llvm::find(CommentHandlers, Handler) == CommentHandlers.end() &&
1383 "Comment handler already registered");
1384 CommentHandlers.push_back(Handler);
1385 }
1386
1387 void Preprocessor::removeCommentHandler(CommentHandler *Handler) {
1388 std::vector<CommentHandler *>::iterator Pos =
1389 llvm::find(CommentHandlers, Handler);
1390 assert(Pos != CommentHandlers.end() && "Comment handler not registered");
1391 CommentHandlers.erase(Pos);
1392 }
1393
1394 bool Preprocessor::HandleComment(Token &result, SourceRange Comment) {
1395 bool AnyPendingTokens = false;
1396 for (std::vector<CommentHandler *>::iterator H = CommentHandlers.begin(),
1397 HEnd = CommentHandlers.end();
1398 H != HEnd; ++H) {
1399 if ((*H)->HandleComment(*this, Comment))
1400 AnyPendingTokens = true;
1401 }
1402 if (!AnyPendingTokens || getCommentRetentionState())
1403 return false;
1404 Lex(result);
1405 return true;
1406 }
1407
1408 ModuleLoader::~ModuleLoader() = default;
1409
1410 CommentHandler::~CommentHandler() = default;
1411
1412 CodeCompletionHandler::~CodeCompletionHandler() = default;
1413
1414 void Preprocessor::createPreprocessingRecord() {
1415 if (Record)
1416 return;
1417
1418 Record = new PreprocessingRecord(getSourceManager());
1419 addPPCallbacks(std::unique_ptr<PPCallbacks>(Record));
1420 }