1 //===--- FrontendActions.cpp ----------------------------------------------===//
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 #include "clang/Frontend/FrontendActions.h"
11 #include "clang/AST/ASTConsumer.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Frontend/ASTConsumers.h"
14 #include "clang/Frontend/CompilerInstance.h"
15 #include "clang/Frontend/FrontendDiagnostic.h"
16 #include "clang/Frontend/MultiplexConsumer.h"
17 #include "clang/Frontend/Utils.h"
18 #include "clang/Lex/HeaderSearch.h"
19 #include "clang/Lex/Preprocessor.h"
20 #include "clang/Lex/PreprocessorOptions.h"
21 #include "clang/Sema/TemplateInstCallback.h"
22 #include "clang/Serialization/ASTReader.h"
23 #include "clang/Serialization/ASTWriter.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 #include "llvm/Support/Path.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include "llvm/Support/YAMLTraits.h"
29 #include <memory>
30 #include <system_error>
31 
32 using namespace clang;
33 
34 namespace {
35 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
36   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
37                                         : nullptr;
38 }
39 
40 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
41   if (Action.hasCodeCompletionSupport() &&
42       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
43     CI.createCodeCompletionConsumer();
44 
45   if (!CI.hasSema())
46     CI.createSema(Action.getTranslationUnitKind(),
47                   GetCodeCompletionConsumer(CI));
48 }
49 } // namespace
50 
51 //===----------------------------------------------------------------------===//
52 // Custom Actions
53 //===----------------------------------------------------------------------===//
54 
55 std::unique_ptr<ASTConsumer>
56 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
57   return llvm::make_unique<ASTConsumer>();
58 }
59 
60 void InitOnlyAction::ExecuteAction() {
61 }
62 
63 //===----------------------------------------------------------------------===//
64 // AST Consumer Actions
65 //===----------------------------------------------------------------------===//
66 
67 std::unique_ptr<ASTConsumer>
68 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
69   if (std::unique_ptr<raw_ostream> OS =
70           CI.createDefaultOutputFile(false, InFile))
71     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
72   return nullptr;
73 }
74 
75 std::unique_ptr<ASTConsumer>
76 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
77   return CreateASTDumper(nullptr /*Dump to stdout.*/,
78                          CI.getFrontendOpts().ASTDumpFilter,
79                          CI.getFrontendOpts().ASTDumpDecls,
80                          CI.getFrontendOpts().ASTDumpAll,
81                          CI.getFrontendOpts().ASTDumpLookups);
82 }
83 
84 std::unique_ptr<ASTConsumer>
85 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
86   return CreateASTDeclNodeLister();
87 }
88 
89 std::unique_ptr<ASTConsumer>
90 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
91   return CreateASTViewer();
92 }
93 
94 std::unique_ptr<ASTConsumer>
95 DeclContextPrintAction::CreateASTConsumer(CompilerInstance &CI,
96                                           StringRef InFile) {
97   return CreateDeclContextPrinter();
98 }
99 
100 std::unique_ptr<ASTConsumer>
101 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
102   std::string Sysroot;
103   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
104     return nullptr;
105 
106   std::string OutputFile;
107   std::unique_ptr<raw_pwrite_stream> OS =
108       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
109   if (!OS)
110     return nullptr;
111 
112   if (!CI.getFrontendOpts().RelocatablePCH)
113     Sysroot.clear();
114 
115   const auto &FrontendOpts = CI.getFrontendOpts();
116   auto Buffer = std::make_shared<PCHBuffer>();
117   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
118   Consumers.push_back(llvm::make_unique<PCHGenerator>(
119                         CI.getPreprocessor(), OutputFile, Sysroot,
120                         Buffer, FrontendOpts.ModuleFileExtensions,
121                         CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
122                         FrontendOpts.IncludeTimestamps));
123   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
124       CI, InFile, OutputFile, std::move(OS), Buffer));
125 
126   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
127 }
128 
129 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
130                                                     std::string &Sysroot) {
131   Sysroot = CI.getHeaderSearchOpts().Sysroot;
132   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
133     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
134     return false;
135   }
136 
137   return true;
138 }
139 
140 std::unique_ptr<llvm::raw_pwrite_stream>
141 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
142                                     std::string &OutputFile) {
143   // We use createOutputFile here because this is exposed via libclang, and we
144   // must disable the RemoveFileOnSignal behavior.
145   // We use a temporary to avoid race conditions.
146   std::unique_ptr<raw_pwrite_stream> OS =
147       CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
148                           /*RemoveFileOnSignal=*/false, InFile,
149                           /*Extension=*/"", /*useTemporary=*/true);
150   if (!OS)
151     return nullptr;
152 
153   OutputFile = CI.getFrontendOpts().OutputFile;
154   return OS;
155 }
156 
157 bool GeneratePCHAction::shouldEraseOutputFiles() {
158   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
159     return false;
160   return ASTFrontendAction::shouldEraseOutputFiles();
161 }
162 
163 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
164   CI.getLangOpts().CompilingPCH = true;
165   return true;
166 }
167 
168 std::unique_ptr<ASTConsumer>
169 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
170                                         StringRef InFile) {
171   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
172   if (!OS)
173     return nullptr;
174 
175   std::string OutputFile = CI.getFrontendOpts().OutputFile;
176   std::string Sysroot;
177 
178   auto Buffer = std::make_shared<PCHBuffer>();
179   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
180 
181   Consumers.push_back(llvm::make_unique<PCHGenerator>(
182                         CI.getPreprocessor(), OutputFile, Sysroot,
183                         Buffer, CI.getFrontendOpts().ModuleFileExtensions,
184                         /*AllowASTWithErrors=*/false,
185                         /*IncludeTimestamps=*/
186                           +CI.getFrontendOpts().BuildingImplicitModule));
187   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
188       CI, InFile, OutputFile, std::move(OS), Buffer));
189   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
190 }
191 
192 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
193     CompilerInstance &CI) {
194   if (!CI.getLangOpts().Modules) {
195     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
196     return false;
197   }
198 
199   return GenerateModuleAction::BeginSourceFileAction(CI);
200 }
201 
202 std::unique_ptr<raw_pwrite_stream>
203 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
204                                                     StringRef InFile) {
205   // If no output file was provided, figure out where this module would go
206   // in the module cache.
207   if (CI.getFrontendOpts().OutputFile.empty()) {
208     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
209     if (ModuleMapFile.empty())
210       ModuleMapFile = InFile;
211 
212     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
213     CI.getFrontendOpts().OutputFile =
214         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
215                                    ModuleMapFile);
216   }
217 
218   // We use createOutputFile here because this is exposed via libclang, and we
219   // must disable the RemoveFileOnSignal behavior.
220   // We use a temporary to avoid race conditions.
221   return CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
222                              /*RemoveFileOnSignal=*/false, InFile,
223                              /*Extension=*/"", /*useTemporary=*/true,
224                              /*CreateMissingDirectories=*/true);
225 }
226 
227 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
228     CompilerInstance &CI) {
229   if (!CI.getLangOpts().ModulesTS) {
230     CI.getDiagnostics().Report(diag::err_module_interface_requires_modules_ts);
231     return false;
232   }
233 
234   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
235 
236   return GenerateModuleAction::BeginSourceFileAction(CI);
237 }
238 
239 std::unique_ptr<raw_pwrite_stream>
240 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
241                                                 StringRef InFile) {
242   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
243 }
244 
245 SyntaxOnlyAction::~SyntaxOnlyAction() {
246 }
247 
248 std::unique_ptr<ASTConsumer>
249 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
250   return llvm::make_unique<ASTConsumer>();
251 }
252 
253 std::unique_ptr<ASTConsumer>
254 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
255                                         StringRef InFile) {
256   return llvm::make_unique<ASTConsumer>();
257 }
258 
259 std::unique_ptr<ASTConsumer>
260 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
261   return llvm::make_unique<ASTConsumer>();
262 }
263 
264 void VerifyPCHAction::ExecuteAction() {
265   CompilerInstance &CI = getCompilerInstance();
266   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
267   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
268   std::unique_ptr<ASTReader> Reader(new ASTReader(
269       CI.getPreprocessor(), &CI.getASTContext(), CI.getPCHContainerReader(),
270       CI.getFrontendOpts().ModuleFileExtensions,
271       Sysroot.empty() ? "" : Sysroot.c_str(),
272       /*DisableValidation*/ false,
273       /*AllowPCHWithCompilerErrors*/ false,
274       /*AllowConfigurationMismatch*/ true,
275       /*ValidateSystemInputs*/ true));
276 
277   Reader->ReadAST(getCurrentFile(),
278                   Preamble ? serialization::MK_Preamble
279                            : serialization::MK_PCH,
280                   SourceLocation(),
281                   ASTReader::ARR_ConfigurationMismatch);
282 }
283 
284 namespace {
285 struct TemplightEntry {
286   std::string Name;
287   std::string Kind;
288   std::string Event;
289   std::string DefinitionLocation;
290   std::string PointOfInstantiation;
291 };
292 } // namespace
293 
294 namespace llvm {
295 namespace yaml {
296 template <> struct MappingTraits<TemplightEntry> {
297   static void mapping(IO &io, TemplightEntry &fields) {
298     io.mapRequired("name", fields.Name);
299     io.mapRequired("kind", fields.Kind);
300     io.mapRequired("event", fields.Event);
301     io.mapRequired("orig", fields.DefinitionLocation);
302     io.mapRequired("poi", fields.PointOfInstantiation);
303   }
304 };
305 } // namespace yaml
306 } // namespace llvm
307 
308 namespace {
309 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
310   using CodeSynthesisContext = Sema::CodeSynthesisContext;
311 
312 public:
313   void initialize(const Sema &) override {}
314 
315   void finalize(const Sema &) override {}
316 
317   void atTemplateBegin(const Sema &TheSema,
318                        const CodeSynthesisContext &Inst) override {
319     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
320   }
321 
322   void atTemplateEnd(const Sema &TheSema,
323                      const CodeSynthesisContext &Inst) override {
324     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
325   }
326 
327 private:
328   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
329     switch (Kind) {
330     case CodeSynthesisContext::TemplateInstantiation:
331       return "TemplateInstantiation";
332     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
333       return "DefaultTemplateArgumentInstantiation";
334     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
335       return "DefaultFunctionArgumentInstantiation";
336     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
337       return "ExplicitTemplateArgumentSubstitution";
338     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
339       return "DeducedTemplateArgumentSubstitution";
340     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
341       return "PriorTemplateArgumentSubstitution";
342     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
343       return "DefaultTemplateArgumentChecking";
344     case CodeSynthesisContext::ExceptionSpecInstantiation:
345       return "ExceptionSpecInstantiation";
346     case CodeSynthesisContext::DeclaringSpecialMember:
347       return "DeclaringSpecialMember";
348     case CodeSynthesisContext::DefiningSynthesizedFunction:
349       return "DefiningSynthesizedFunction";
350     case CodeSynthesisContext::Memoization:
351       return "Memoization";
352     }
353     return "";
354   }
355 
356   template <bool BeginInstantiation>
357   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
358                                     const CodeSynthesisContext &Inst) {
359     std::string YAML;
360     {
361       llvm::raw_string_ostream OS(YAML);
362       llvm::yaml::Output YO(OS);
363       TemplightEntry Entry =
364           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
365       llvm::yaml::EmptyContext Context;
366       llvm::yaml::yamlize(YO, Entry, true, Context);
367     }
368     Out << "---" << YAML << "\n";
369   }
370 
371   template <bool BeginInstantiation>
372   static TemplightEntry getTemplightEntry(const Sema &TheSema,
373                                           const CodeSynthesisContext &Inst) {
374     TemplightEntry Entry;
375     Entry.Kind = toString(Inst.Kind);
376     Entry.Event = BeginInstantiation ? "Begin" : "End";
377     if (auto *NamedTemplate = dyn_cast_or_null<NamedDecl>(Inst.Entity)) {
378       llvm::raw_string_ostream OS(Entry.Name);
379       NamedTemplate->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
380       const PresumedLoc DefLoc =
381         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
382       if(!DefLoc.isInvalid())
383         Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
384                                    std::to_string(DefLoc.getLine()) + ":" +
385                                    std::to_string(DefLoc.getColumn());
386     }
387     const PresumedLoc PoiLoc =
388         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
389     if (!PoiLoc.isInvalid()) {
390       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
391                                    std::to_string(PoiLoc.getLine()) + ":" +
392                                    std::to_string(PoiLoc.getColumn());
393     }
394     return Entry;
395   }
396 };
397 } // namespace
398 
399 std::unique_ptr<ASTConsumer>
400 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
401   return llvm::make_unique<ASTConsumer>();
402 }
403 
404 void TemplightDumpAction::ExecuteAction() {
405   CompilerInstance &CI = getCompilerInstance();
406 
407   // This part is normally done by ASTFrontEndAction, but needs to happen
408   // before Templight observers can be created
409   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
410   // here so the source manager would be initialized.
411   EnsureSemaIsCreated(CI, *this);
412 
413   CI.getSema().TemplateInstCallbacks.push_back(
414       llvm::make_unique<DefaultTemplateInstCallback>());
415   ASTFrontendAction::ExecuteAction();
416 }
417 
418 namespace {
419   /// AST reader listener that dumps module information for a module
420   /// file.
421   class DumpModuleInfoListener : public ASTReaderListener {
422     llvm::raw_ostream &Out;
423 
424   public:
425     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
426 
427 #define DUMP_BOOLEAN(Value, Text)                       \
428     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
429 
430     bool ReadFullVersionInformation(StringRef FullVersion) override {
431       Out.indent(2)
432         << "Generated by "
433         << (FullVersion == getClangFullRepositoryVersion()? "this"
434                                                           : "a different")
435         << " Clang: " << FullVersion << "\n";
436       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
437     }
438 
439     void ReadModuleName(StringRef ModuleName) override {
440       Out.indent(2) << "Module name: " << ModuleName << "\n";
441     }
442     void ReadModuleMapFile(StringRef ModuleMapPath) override {
443       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
444     }
445 
446     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
447                              bool AllowCompatibleDifferences) override {
448       Out.indent(2) << "Language options:\n";
449 #define LANGOPT(Name, Bits, Default, Description) \
450       DUMP_BOOLEAN(LangOpts.Name, Description);
451 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
452       Out.indent(4) << Description << ": "                   \
453                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
454 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
455       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
456 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
457 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
458 #include "clang/Basic/LangOptions.def"
459 
460       if (!LangOpts.ModuleFeatures.empty()) {
461         Out.indent(4) << "Module features:\n";
462         for (StringRef Feature : LangOpts.ModuleFeatures)
463           Out.indent(6) << Feature << "\n";
464       }
465 
466       return false;
467     }
468 
469     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
470                            bool AllowCompatibleDifferences) override {
471       Out.indent(2) << "Target options:\n";
472       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
473       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
474       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
475 
476       if (!TargetOpts.FeaturesAsWritten.empty()) {
477         Out.indent(4) << "Target features:\n";
478         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
479              I != N; ++I) {
480           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
481         }
482       }
483 
484       return false;
485     }
486 
487     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
488                                bool Complain) override {
489       Out.indent(2) << "Diagnostic options:\n";
490 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
491 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
492       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
493 #define VALUE_DIAGOPT(Name, Bits, Default) \
494       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
495 #include "clang/Basic/DiagnosticOptions.def"
496 
497       Out.indent(4) << "Diagnostic flags:\n";
498       for (const std::string &Warning : DiagOpts->Warnings)
499         Out.indent(6) << "-W" << Warning << "\n";
500       for (const std::string &Remark : DiagOpts->Remarks)
501         Out.indent(6) << "-R" << Remark << "\n";
502 
503       return false;
504     }
505 
506     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
507                                  StringRef SpecificModuleCachePath,
508                                  bool Complain) override {
509       Out.indent(2) << "Header search options:\n";
510       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
511       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
512       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
513       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
514                    "Use builtin include directories [-nobuiltininc]");
515       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
516                    "Use standard system include directories [-nostdinc]");
517       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
518                    "Use standard C++ include directories [-nostdinc++]");
519       DUMP_BOOLEAN(HSOpts.UseLibcxx,
520                    "Use libc++ (rather than libstdc++) [-stdlib=]");
521       return false;
522     }
523 
524     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
525                                  bool Complain,
526                                  std::string &SuggestedPredefines) override {
527       Out.indent(2) << "Preprocessor options:\n";
528       DUMP_BOOLEAN(PPOpts.UsePredefines,
529                    "Uses compiler/target-specific predefines [-undef]");
530       DUMP_BOOLEAN(PPOpts.DetailedRecord,
531                    "Uses detailed preprocessing record (for indexing)");
532 
533       if (!PPOpts.Macros.empty()) {
534         Out.indent(4) << "Predefined macros:\n";
535       }
536 
537       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
538              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
539            I != IEnd; ++I) {
540         Out.indent(6);
541         if (I->second)
542           Out << "-U";
543         else
544           Out << "-D";
545         Out << I->first << "\n";
546       }
547       return false;
548     }
549 
550     /// Indicates that a particular module file extension has been read.
551     void readModuleFileExtension(
552            const ModuleFileExtensionMetadata &Metadata) override {
553       Out.indent(2) << "Module file extension '"
554                     << Metadata.BlockName << "' " << Metadata.MajorVersion
555                     << "." << Metadata.MinorVersion;
556       if (!Metadata.UserInfo.empty()) {
557         Out << ": ";
558         Out.write_escaped(Metadata.UserInfo);
559       }
560 
561       Out << "\n";
562     }
563 #undef DUMP_BOOLEAN
564   };
565 }
566 
567 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
568   // The Object file reader also supports raw ast files and there is no point in
569   // being strict about the module file format in -module-file-info mode.
570   CI.getHeaderSearchOpts().ModuleFormat = "obj";
571   return true;
572 }
573 
574 void DumpModuleInfoAction::ExecuteAction() {
575   // Set up the output file.
576   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
577   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
578   if (!OutputFileName.empty() && OutputFileName != "-") {
579     std::error_code EC;
580     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
581                                            llvm::sys::fs::F_Text));
582   }
583   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
584 
585   Out << "Information for module file '" << getCurrentFile() << "':\n";
586   auto &FileMgr = getCompilerInstance().getFileManager();
587   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
588   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
589   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
590                 Magic[2] == 'C' && Magic[3] == 'H');
591   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
592 
593   Preprocessor &PP = getCompilerInstance().getPreprocessor();
594   DumpModuleInfoListener Listener(Out);
595   HeaderSearchOptions &HSOpts =
596       PP.getHeaderSearchInfo().getHeaderSearchOpts();
597   ASTReader::readASTFileControlBlock(
598       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
599       /*FindModuleFileExtensions=*/true, Listener,
600       HSOpts.ModulesValidateDiagnosticOptions);
601 }
602 
603 //===----------------------------------------------------------------------===//
604 // Preprocessor Actions
605 //===----------------------------------------------------------------------===//
606 
607 void DumpRawTokensAction::ExecuteAction() {
608   Preprocessor &PP = getCompilerInstance().getPreprocessor();
609   SourceManager &SM = PP.getSourceManager();
610 
611   // Start lexing the specified input file.
612   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
613   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
614   RawLex.SetKeepWhitespaceMode(true);
615 
616   Token RawTok;
617   RawLex.LexFromRawLexer(RawTok);
618   while (RawTok.isNot(tok::eof)) {
619     PP.DumpToken(RawTok, true);
620     llvm::errs() << "\n";
621     RawLex.LexFromRawLexer(RawTok);
622   }
623 }
624 
625 void DumpTokensAction::ExecuteAction() {
626   Preprocessor &PP = getCompilerInstance().getPreprocessor();
627   // Start preprocessing the specified input file.
628   Token Tok;
629   PP.EnterMainSourceFile();
630   do {
631     PP.Lex(Tok);
632     PP.DumpToken(Tok, true);
633     llvm::errs() << "\n";
634   } while (Tok.isNot(tok::eof));
635 }
636 
637 void GeneratePTHAction::ExecuteAction() {
638   CompilerInstance &CI = getCompilerInstance();
639   std::unique_ptr<raw_pwrite_stream> OS =
640       CI.createDefaultOutputFile(true, getCurrentFile());
641   if (!OS)
642     return;
643 
644   CacheTokens(CI.getPreprocessor(), OS.get());
645 }
646 
647 void PreprocessOnlyAction::ExecuteAction() {
648   Preprocessor &PP = getCompilerInstance().getPreprocessor();
649 
650   // Ignore unknown pragmas.
651   PP.IgnorePragmas();
652 
653   Token Tok;
654   // Start parsing the specified input file.
655   PP.EnterMainSourceFile();
656   do {
657     PP.Lex(Tok);
658   } while (Tok.isNot(tok::eof));
659 }
660 
661 void PrintPreprocessedAction::ExecuteAction() {
662   CompilerInstance &CI = getCompilerInstance();
663   // Output file may need to be set to 'Binary', to avoid converting Unix style
664   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
665   //
666   // Look to see what type of line endings the file uses. If there's a
667   // CRLF, then we won't open the file up in binary mode. If there is
668   // just an LF or CR, then we will open the file up in binary mode.
669   // In this fashion, the output format should match the input format, unless
670   // the input format has inconsistent line endings.
671   //
672   // This should be a relatively fast operation since most files won't have
673   // all of their source code on a single line. However, that is still a
674   // concern, so if we scan for too long, we'll just assume the file should
675   // be opened in binary mode.
676   bool BinaryMode = true;
677   bool InvalidFile = false;
678   const SourceManager& SM = CI.getSourceManager();
679   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
680                                                      &InvalidFile);
681   if (!InvalidFile) {
682     const char *cur = Buffer->getBufferStart();
683     const char *end = Buffer->getBufferEnd();
684     const char *next = (cur != end) ? cur + 1 : end;
685 
686     // Limit ourselves to only scanning 256 characters into the source
687     // file.  This is mostly a sanity check in case the file has no
688     // newlines whatsoever.
689     if (end - cur > 256) end = cur + 256;
690 
691     while (next < end) {
692       if (*cur == 0x0D) {  // CR
693         if (*next == 0x0A)  // CRLF
694           BinaryMode = false;
695 
696         break;
697       } else if (*cur == 0x0A)  // LF
698         break;
699 
700       ++cur;
701       ++next;
702     }
703   }
704 
705   std::unique_ptr<raw_ostream> OS =
706       CI.createDefaultOutputFile(BinaryMode, getCurrentFile());
707   if (!OS) return;
708 
709   // If we're preprocessing a module map, start by dumping the contents of the
710   // module itself before switching to the input buffer.
711   auto &Input = getCurrentInput();
712   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
713     if (Input.isFile()) {
714       (*OS) << "# 1 \"";
715       OS->write_escaped(Input.getFile());
716       (*OS) << "\"\n";
717     }
718     // FIXME: Include additional information here so that we don't need the
719     // original source files to exist on disk.
720     getCurrentModule()->print(*OS);
721     (*OS) << "#pragma clang module contents\n";
722   }
723 
724   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
725                            CI.getPreprocessorOutputOpts());
726 }
727 
728 void PrintPreambleAction::ExecuteAction() {
729   switch (getCurrentFileKind().getLanguage()) {
730   case InputKind::C:
731   case InputKind::CXX:
732   case InputKind::ObjC:
733   case InputKind::ObjCXX:
734   case InputKind::OpenCL:
735   case InputKind::CUDA:
736   case InputKind::HIP:
737     break;
738 
739   case InputKind::Unknown:
740   case InputKind::Asm:
741   case InputKind::LLVM_IR:
742   case InputKind::RenderScript:
743     // We can't do anything with these.
744     return;
745   }
746 
747   // We don't expect to find any #include directives in a preprocessed input.
748   if (getCurrentFileKind().isPreprocessed())
749     return;
750 
751   CompilerInstance &CI = getCompilerInstance();
752   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
753   if (Buffer) {
754     unsigned Preamble =
755         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
756     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
757   }
758 }
759 
760 void DumpCompilerOptionsAction::ExecuteAction() {
761   CompilerInstance &CI = getCompilerInstance();
762   std::unique_ptr<raw_ostream> OSP =
763       CI.createDefaultOutputFile(false, getCurrentFile());
764   if (!OSP)
765     return;
766 
767   raw_ostream &OS = *OSP;
768   const Preprocessor &PP = CI.getPreprocessor();
769   const LangOptions &LangOpts = PP.getLangOpts();
770 
771   // FIXME: Rather than manually format the JSON (which is awkward due to
772   // needing to remove trailing commas), this should make use of a JSON library.
773   // FIXME: Instead of printing enums as an integral value and specifying the
774   // type as a separate field, use introspection to print the enumerator.
775 
776   OS << "{\n";
777   OS << "\n\"features\" : [\n";
778   {
779     llvm::SmallString<128> Str;
780 #define FEATURE(Name, Predicate)                                               \
781   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
782       .toVector(Str);
783 #include "clang/Basic/Features.def"
784 #undef FEATURE
785     // Remove the newline and comma from the last entry to ensure this remains
786     // valid JSON.
787     OS << Str.substr(0, Str.size() - 2);
788   }
789   OS << "\n],\n";
790 
791   OS << "\n\"extensions\" : [\n";
792   {
793     llvm::SmallString<128> Str;
794 #define EXTENSION(Name, Predicate)                                             \
795   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
796       .toVector(Str);
797 #include "clang/Basic/Features.def"
798 #undef EXTENSION
799     // Remove the newline and comma from the last entry to ensure this remains
800     // valid JSON.
801     OS << Str.substr(0, Str.size() - 2);
802   }
803   OS << "\n]\n";
804 
805   OS << "}";
806 }
807