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::ExceptionSpecEvaluation:
345       return "ExceptionSpecEvaluation";
346     case CodeSynthesisContext::ExceptionSpecInstantiation:
347       return "ExceptionSpecInstantiation";
348     case CodeSynthesisContext::DeclaringSpecialMember:
349       return "DeclaringSpecialMember";
350     case CodeSynthesisContext::DefiningSynthesizedFunction:
351       return "DefiningSynthesizedFunction";
352     case CodeSynthesisContext::Memoization:
353       return "Memoization";
354     }
355     return "";
356   }
357 
358   template <bool BeginInstantiation>
359   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
360                                     const CodeSynthesisContext &Inst) {
361     std::string YAML;
362     {
363       llvm::raw_string_ostream OS(YAML);
364       llvm::yaml::Output YO(OS);
365       TemplightEntry Entry =
366           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
367       llvm::yaml::EmptyContext Context;
368       llvm::yaml::yamlize(YO, Entry, true, Context);
369     }
370     Out << "---" << YAML << "\n";
371   }
372 
373   template <bool BeginInstantiation>
374   static TemplightEntry getTemplightEntry(const Sema &TheSema,
375                                           const CodeSynthesisContext &Inst) {
376     TemplightEntry Entry;
377     Entry.Kind = toString(Inst.Kind);
378     Entry.Event = BeginInstantiation ? "Begin" : "End";
379     if (auto *NamedTemplate = dyn_cast_or_null<NamedDecl>(Inst.Entity)) {
380       llvm::raw_string_ostream OS(Entry.Name);
381       NamedTemplate->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
382       const PresumedLoc DefLoc =
383         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
384       if(!DefLoc.isInvalid())
385         Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
386                                    std::to_string(DefLoc.getLine()) + ":" +
387                                    std::to_string(DefLoc.getColumn());
388     }
389     const PresumedLoc PoiLoc =
390         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
391     if (!PoiLoc.isInvalid()) {
392       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
393                                    std::to_string(PoiLoc.getLine()) + ":" +
394                                    std::to_string(PoiLoc.getColumn());
395     }
396     return Entry;
397   }
398 };
399 } // namespace
400 
401 std::unique_ptr<ASTConsumer>
402 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
403   return llvm::make_unique<ASTConsumer>();
404 }
405 
406 void TemplightDumpAction::ExecuteAction() {
407   CompilerInstance &CI = getCompilerInstance();
408 
409   // This part is normally done by ASTFrontEndAction, but needs to happen
410   // before Templight observers can be created
411   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
412   // here so the source manager would be initialized.
413   EnsureSemaIsCreated(CI, *this);
414 
415   CI.getSema().TemplateInstCallbacks.push_back(
416       llvm::make_unique<DefaultTemplateInstCallback>());
417   ASTFrontendAction::ExecuteAction();
418 }
419 
420 namespace {
421   /// AST reader listener that dumps module information for a module
422   /// file.
423   class DumpModuleInfoListener : public ASTReaderListener {
424     llvm::raw_ostream &Out;
425 
426   public:
427     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
428 
429 #define DUMP_BOOLEAN(Value, Text)                       \
430     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
431 
432     bool ReadFullVersionInformation(StringRef FullVersion) override {
433       Out.indent(2)
434         << "Generated by "
435         << (FullVersion == getClangFullRepositoryVersion()? "this"
436                                                           : "a different")
437         << " Clang: " << FullVersion << "\n";
438       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
439     }
440 
441     void ReadModuleName(StringRef ModuleName) override {
442       Out.indent(2) << "Module name: " << ModuleName << "\n";
443     }
444     void ReadModuleMapFile(StringRef ModuleMapPath) override {
445       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
446     }
447 
448     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
449                              bool AllowCompatibleDifferences) override {
450       Out.indent(2) << "Language options:\n";
451 #define LANGOPT(Name, Bits, Default, Description) \
452       DUMP_BOOLEAN(LangOpts.Name, Description);
453 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
454       Out.indent(4) << Description << ": "                   \
455                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
456 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
457       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
458 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
459 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
460 #include "clang/Basic/LangOptions.def"
461 
462       if (!LangOpts.ModuleFeatures.empty()) {
463         Out.indent(4) << "Module features:\n";
464         for (StringRef Feature : LangOpts.ModuleFeatures)
465           Out.indent(6) << Feature << "\n";
466       }
467 
468       return false;
469     }
470 
471     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
472                            bool AllowCompatibleDifferences) override {
473       Out.indent(2) << "Target options:\n";
474       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
475       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
476       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
477 
478       if (!TargetOpts.FeaturesAsWritten.empty()) {
479         Out.indent(4) << "Target features:\n";
480         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
481              I != N; ++I) {
482           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
483         }
484       }
485 
486       return false;
487     }
488 
489     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
490                                bool Complain) override {
491       Out.indent(2) << "Diagnostic options:\n";
492 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
493 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
494       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
495 #define VALUE_DIAGOPT(Name, Bits, Default) \
496       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
497 #include "clang/Basic/DiagnosticOptions.def"
498 
499       Out.indent(4) << "Diagnostic flags:\n";
500       for (const std::string &Warning : DiagOpts->Warnings)
501         Out.indent(6) << "-W" << Warning << "\n";
502       for (const std::string &Remark : DiagOpts->Remarks)
503         Out.indent(6) << "-R" << Remark << "\n";
504 
505       return false;
506     }
507 
508     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
509                                  StringRef SpecificModuleCachePath,
510                                  bool Complain) override {
511       Out.indent(2) << "Header search options:\n";
512       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
513       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
514       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
515       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
516                    "Use builtin include directories [-nobuiltininc]");
517       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
518                    "Use standard system include directories [-nostdinc]");
519       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
520                    "Use standard C++ include directories [-nostdinc++]");
521       DUMP_BOOLEAN(HSOpts.UseLibcxx,
522                    "Use libc++ (rather than libstdc++) [-stdlib=]");
523       return false;
524     }
525 
526     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
527                                  bool Complain,
528                                  std::string &SuggestedPredefines) override {
529       Out.indent(2) << "Preprocessor options:\n";
530       DUMP_BOOLEAN(PPOpts.UsePredefines,
531                    "Uses compiler/target-specific predefines [-undef]");
532       DUMP_BOOLEAN(PPOpts.DetailedRecord,
533                    "Uses detailed preprocessing record (for indexing)");
534 
535       if (!PPOpts.Macros.empty()) {
536         Out.indent(4) << "Predefined macros:\n";
537       }
538 
539       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
540              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
541            I != IEnd; ++I) {
542         Out.indent(6);
543         if (I->second)
544           Out << "-U";
545         else
546           Out << "-D";
547         Out << I->first << "\n";
548       }
549       return false;
550     }
551 
552     /// Indicates that a particular module file extension has been read.
553     void readModuleFileExtension(
554            const ModuleFileExtensionMetadata &Metadata) override {
555       Out.indent(2) << "Module file extension '"
556                     << Metadata.BlockName << "' " << Metadata.MajorVersion
557                     << "." << Metadata.MinorVersion;
558       if (!Metadata.UserInfo.empty()) {
559         Out << ": ";
560         Out.write_escaped(Metadata.UserInfo);
561       }
562 
563       Out << "\n";
564     }
565 
566     /// Tells the \c ASTReaderListener that we want to receive the
567     /// input files of the AST file via \c visitInputFile.
568     bool needsInputFileVisitation() override { return true; }
569 
570     /// Tells the \c ASTReaderListener that we want to receive the
571     /// input files of the AST file via \c visitInputFile.
572     bool needsSystemInputFileVisitation() override { return true; }
573 
574     /// Indicates that the AST file contains particular input file.
575     ///
576     /// \returns true to continue receiving the next input file, false to stop.
577     bool visitInputFile(StringRef Filename, bool isSystem,
578                         bool isOverridden, bool isExplicitModule) override {
579 
580       Out.indent(2) << "Input file: " << Filename;
581 
582       if (isSystem || isOverridden || isExplicitModule) {
583         Out << " [";
584         if (isSystem) {
585           Out << "System";
586           if (isOverridden || isExplicitModule)
587             Out << ", ";
588         }
589         if (isOverridden) {
590           Out << "Overridden";
591           if (isExplicitModule)
592             Out << ", ";
593         }
594         if (isExplicitModule)
595           Out << "ExplicitModule";
596 
597         Out << "]";
598       }
599 
600       Out << "\n";
601 
602       return true;
603     }
604 
605     /// Returns true if this \c ASTReaderListener wants to receive the
606     /// imports of the AST file via \c visitImport, false otherwise.
607     bool needsImportVisitation() const override { return true; }
608 
609     /// If needsImportVisitation returns \c true, this is called for each
610     /// AST file imported by this AST file.
611     void visitImport(StringRef ModuleName, StringRef Filename) override {
612       Out.indent(2) << "Imports module '" << ModuleName
613                     << "': " << Filename.str() << "\n";
614     }
615 #undef DUMP_BOOLEAN
616   };
617 }
618 
619 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
620   // The Object file reader also supports raw ast files and there is no point in
621   // being strict about the module file format in -module-file-info mode.
622   CI.getHeaderSearchOpts().ModuleFormat = "obj";
623   return true;
624 }
625 
626 void DumpModuleInfoAction::ExecuteAction() {
627   // Set up the output file.
628   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
629   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
630   if (!OutputFileName.empty() && OutputFileName != "-") {
631     std::error_code EC;
632     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
633                                            llvm::sys::fs::F_Text));
634   }
635   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
636 
637   Out << "Information for module file '" << getCurrentFile() << "':\n";
638   auto &FileMgr = getCompilerInstance().getFileManager();
639   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
640   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
641   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
642                 Magic[2] == 'C' && Magic[3] == 'H');
643   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
644 
645   Preprocessor &PP = getCompilerInstance().getPreprocessor();
646   DumpModuleInfoListener Listener(Out);
647   HeaderSearchOptions &HSOpts =
648       PP.getHeaderSearchInfo().getHeaderSearchOpts();
649   ASTReader::readASTFileControlBlock(
650       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
651       /*FindModuleFileExtensions=*/true, Listener,
652       HSOpts.ModulesValidateDiagnosticOptions);
653 }
654 
655 //===----------------------------------------------------------------------===//
656 // Preprocessor Actions
657 //===----------------------------------------------------------------------===//
658 
659 void DumpRawTokensAction::ExecuteAction() {
660   Preprocessor &PP = getCompilerInstance().getPreprocessor();
661   SourceManager &SM = PP.getSourceManager();
662 
663   // Start lexing the specified input file.
664   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
665   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
666   RawLex.SetKeepWhitespaceMode(true);
667 
668   Token RawTok;
669   RawLex.LexFromRawLexer(RawTok);
670   while (RawTok.isNot(tok::eof)) {
671     PP.DumpToken(RawTok, true);
672     llvm::errs() << "\n";
673     RawLex.LexFromRawLexer(RawTok);
674   }
675 }
676 
677 void DumpTokensAction::ExecuteAction() {
678   Preprocessor &PP = getCompilerInstance().getPreprocessor();
679   // Start preprocessing the specified input file.
680   Token Tok;
681   PP.EnterMainSourceFile();
682   do {
683     PP.Lex(Tok);
684     PP.DumpToken(Tok, true);
685     llvm::errs() << "\n";
686   } while (Tok.isNot(tok::eof));
687 }
688 
689 void GeneratePTHAction::ExecuteAction() {
690   CompilerInstance &CI = getCompilerInstance();
691   std::unique_ptr<raw_pwrite_stream> OS =
692       CI.createDefaultOutputFile(true, getCurrentFile());
693   if (!OS)
694     return;
695 
696   CacheTokens(CI.getPreprocessor(), OS.get());
697 }
698 
699 void PreprocessOnlyAction::ExecuteAction() {
700   Preprocessor &PP = getCompilerInstance().getPreprocessor();
701 
702   // Ignore unknown pragmas.
703   PP.IgnorePragmas();
704 
705   Token Tok;
706   // Start parsing the specified input file.
707   PP.EnterMainSourceFile();
708   do {
709     PP.Lex(Tok);
710   } while (Tok.isNot(tok::eof));
711 }
712 
713 void PrintPreprocessedAction::ExecuteAction() {
714   CompilerInstance &CI = getCompilerInstance();
715   // Output file may need to be set to 'Binary', to avoid converting Unix style
716   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
717   //
718   // Look to see what type of line endings the file uses. If there's a
719   // CRLF, then we won't open the file up in binary mode. If there is
720   // just an LF or CR, then we will open the file up in binary mode.
721   // In this fashion, the output format should match the input format, unless
722   // the input format has inconsistent line endings.
723   //
724   // This should be a relatively fast operation since most files won't have
725   // all of their source code on a single line. However, that is still a
726   // concern, so if we scan for too long, we'll just assume the file should
727   // be opened in binary mode.
728   bool BinaryMode = true;
729   bool InvalidFile = false;
730   const SourceManager& SM = CI.getSourceManager();
731   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
732                                                      &InvalidFile);
733   if (!InvalidFile) {
734     const char *cur = Buffer->getBufferStart();
735     const char *end = Buffer->getBufferEnd();
736     const char *next = (cur != end) ? cur + 1 : end;
737 
738     // Limit ourselves to only scanning 256 characters into the source
739     // file.  This is mostly a sanity check in case the file has no
740     // newlines whatsoever.
741     if (end - cur > 256) end = cur + 256;
742 
743     while (next < end) {
744       if (*cur == 0x0D) {  // CR
745         if (*next == 0x0A)  // CRLF
746           BinaryMode = false;
747 
748         break;
749       } else if (*cur == 0x0A)  // LF
750         break;
751 
752       ++cur;
753       ++next;
754     }
755   }
756 
757   std::unique_ptr<raw_ostream> OS =
758       CI.createDefaultOutputFile(BinaryMode, getCurrentFile());
759   if (!OS) return;
760 
761   // If we're preprocessing a module map, start by dumping the contents of the
762   // module itself before switching to the input buffer.
763   auto &Input = getCurrentInput();
764   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
765     if (Input.isFile()) {
766       (*OS) << "# 1 \"";
767       OS->write_escaped(Input.getFile());
768       (*OS) << "\"\n";
769     }
770     // FIXME: Include additional information here so that we don't need the
771     // original source files to exist on disk.
772     getCurrentModule()->print(*OS);
773     (*OS) << "#pragma clang module contents\n";
774   }
775 
776   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
777                            CI.getPreprocessorOutputOpts());
778 }
779 
780 void PrintPreambleAction::ExecuteAction() {
781   switch (getCurrentFileKind().getLanguage()) {
782   case InputKind::C:
783   case InputKind::CXX:
784   case InputKind::ObjC:
785   case InputKind::ObjCXX:
786   case InputKind::OpenCL:
787   case InputKind::CUDA:
788   case InputKind::HIP:
789     break;
790 
791   case InputKind::Unknown:
792   case InputKind::Asm:
793   case InputKind::LLVM_IR:
794   case InputKind::RenderScript:
795     // We can't do anything with these.
796     return;
797   }
798 
799   // We don't expect to find any #include directives in a preprocessed input.
800   if (getCurrentFileKind().isPreprocessed())
801     return;
802 
803   CompilerInstance &CI = getCompilerInstance();
804   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
805   if (Buffer) {
806     unsigned Preamble =
807         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
808     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
809   }
810 }
811 
812 void DumpCompilerOptionsAction::ExecuteAction() {
813   CompilerInstance &CI = getCompilerInstance();
814   std::unique_ptr<raw_ostream> OSP =
815       CI.createDefaultOutputFile(false, getCurrentFile());
816   if (!OSP)
817     return;
818 
819   raw_ostream &OS = *OSP;
820   const Preprocessor &PP = CI.getPreprocessor();
821   const LangOptions &LangOpts = PP.getLangOpts();
822 
823   // FIXME: Rather than manually format the JSON (which is awkward due to
824   // needing to remove trailing commas), this should make use of a JSON library.
825   // FIXME: Instead of printing enums as an integral value and specifying the
826   // type as a separate field, use introspection to print the enumerator.
827 
828   OS << "{\n";
829   OS << "\n\"features\" : [\n";
830   {
831     llvm::SmallString<128> Str;
832 #define FEATURE(Name, Predicate)                                               \
833   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
834       .toVector(Str);
835 #include "clang/Basic/Features.def"
836 #undef FEATURE
837     // Remove the newline and comma from the last entry to ensure this remains
838     // valid JSON.
839     OS << Str.substr(0, Str.size() - 2);
840   }
841   OS << "\n],\n";
842 
843   OS << "\n\"extensions\" : [\n";
844   {
845     llvm::SmallString<128> Str;
846 #define EXTENSION(Name, Predicate)                                             \
847   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
848       .toVector(Str);
849 #include "clang/Basic/Features.def"
850 #undef EXTENSION
851     // Remove the newline and comma from the last entry to ensure this remains
852     // valid JSON.
853     OS << Str.substr(0, Str.size() - 2);
854   }
855   OS << "\n]\n";
856 
857   OS << "}";
858 }
859