1 //===--- FrontendActions.cpp ----------------------------------------------===//
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 #include "clang/Frontend/FrontendActions.h"
10 #include "clang/AST/ASTConsumer.h"
11 #include "clang/Basic/FileManager.h"
12 #include "clang/Frontend/ASTConsumers.h"
13 #include "clang/Frontend/CompilerInstance.h"
14 #include "clang/Frontend/FrontendDiagnostic.h"
15 #include "clang/Frontend/MultiplexConsumer.h"
16 #include "clang/Frontend/Utils.h"
17 #include "clang/Lex/HeaderSearch.h"
18 #include "clang/Lex/Preprocessor.h"
19 #include "clang/Lex/PreprocessorOptions.h"
20 #include "clang/Sema/TemplateInstCallback.h"
21 #include "clang/Serialization/ASTReader.h"
22 #include "clang/Serialization/ASTWriter.h"
23 #include "llvm/Support/FileSystem.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Support/Path.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include "llvm/Support/YAMLTraits.h"
28 #include <memory>
29 #include <system_error>
30 
31 using namespace clang;
32 
33 namespace {
34 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
35   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
36                                         : nullptr;
37 }
38 
39 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
40   if (Action.hasCodeCompletionSupport() &&
41       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
42     CI.createCodeCompletionConsumer();
43 
44   if (!CI.hasSema())
45     CI.createSema(Action.getTranslationUnitKind(),
46                   GetCodeCompletionConsumer(CI));
47 }
48 } // namespace
49 
50 //===----------------------------------------------------------------------===//
51 // Custom Actions
52 //===----------------------------------------------------------------------===//
53 
54 std::unique_ptr<ASTConsumer>
55 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
56   return llvm::make_unique<ASTConsumer>();
57 }
58 
59 void InitOnlyAction::ExecuteAction() {
60 }
61 
62 //===----------------------------------------------------------------------===//
63 // AST Consumer Actions
64 //===----------------------------------------------------------------------===//
65 
66 std::unique_ptr<ASTConsumer>
67 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
68   if (std::unique_ptr<raw_ostream> OS =
69           CI.createDefaultOutputFile(false, InFile))
70     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
71   return nullptr;
72 }
73 
74 std::unique_ptr<ASTConsumer>
75 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
76   const FrontendOptions &Opts = CI.getFrontendOpts();
77   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
78                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
79                          Opts.ASTDumpLookups, Opts.ASTDumpFormat);
80 }
81 
82 std::unique_ptr<ASTConsumer>
83 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
84   return CreateASTDeclNodeLister();
85 }
86 
87 std::unique_ptr<ASTConsumer>
88 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
89   return CreateASTViewer();
90 }
91 
92 std::unique_ptr<ASTConsumer>
93 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
94   std::string Sysroot;
95   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
96     return nullptr;
97 
98   std::string OutputFile;
99   std::unique_ptr<raw_pwrite_stream> OS =
100       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
101   if (!OS)
102     return nullptr;
103 
104   if (!CI.getFrontendOpts().RelocatablePCH)
105     Sysroot.clear();
106 
107   const auto &FrontendOpts = CI.getFrontendOpts();
108   auto Buffer = std::make_shared<PCHBuffer>();
109   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
110   Consumers.push_back(llvm::make_unique<PCHGenerator>(
111       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
112       FrontendOpts.ModuleFileExtensions,
113       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
114       FrontendOpts.IncludeTimestamps, +CI.getLangOpts().CacheGeneratedPCH));
115   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
116       CI, InFile, OutputFile, std::move(OS), Buffer));
117 
118   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
119 }
120 
121 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
122                                                     std::string &Sysroot) {
123   Sysroot = CI.getHeaderSearchOpts().Sysroot;
124   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
125     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
126     return false;
127   }
128 
129   return true;
130 }
131 
132 std::unique_ptr<llvm::raw_pwrite_stream>
133 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
134                                     std::string &OutputFile) {
135   // We use createOutputFile here because this is exposed via libclang, and we
136   // must disable the RemoveFileOnSignal behavior.
137   // We use a temporary to avoid race conditions.
138   std::unique_ptr<raw_pwrite_stream> OS =
139       CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
140                           /*RemoveFileOnSignal=*/false, InFile,
141                           /*Extension=*/"", /*useTemporary=*/true);
142   if (!OS)
143     return nullptr;
144 
145   OutputFile = CI.getFrontendOpts().OutputFile;
146   return OS;
147 }
148 
149 bool GeneratePCHAction::shouldEraseOutputFiles() {
150   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
151     return false;
152   return ASTFrontendAction::shouldEraseOutputFiles();
153 }
154 
155 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
156   CI.getLangOpts().CompilingPCH = true;
157   return true;
158 }
159 
160 std::unique_ptr<ASTConsumer>
161 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
162                                         StringRef InFile) {
163   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
164   if (!OS)
165     return nullptr;
166 
167   std::string OutputFile = CI.getFrontendOpts().OutputFile;
168   std::string Sysroot;
169 
170   auto Buffer = std::make_shared<PCHBuffer>();
171   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
172 
173   Consumers.push_back(llvm::make_unique<PCHGenerator>(
174       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
175       CI.getFrontendOpts().ModuleFileExtensions,
176       /*AllowASTWithErrors=*/false,
177       /*IncludeTimestamps=*/
178       +CI.getFrontendOpts().BuildingImplicitModule,
179       /*ShouldCacheASTInMemory=*/
180       +CI.getFrontendOpts().BuildingImplicitModule));
181   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
182       CI, InFile, OutputFile, std::move(OS), Buffer));
183   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
184 }
185 
186 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
187     CompilerInstance &CI) {
188   if (!CI.getLangOpts().Modules) {
189     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
190     return false;
191   }
192 
193   return GenerateModuleAction::BeginSourceFileAction(CI);
194 }
195 
196 std::unique_ptr<raw_pwrite_stream>
197 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
198                                                     StringRef InFile) {
199   // If no output file was provided, figure out where this module would go
200   // in the module cache.
201   if (CI.getFrontendOpts().OutputFile.empty()) {
202     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
203     if (ModuleMapFile.empty())
204       ModuleMapFile = InFile;
205 
206     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
207     CI.getFrontendOpts().OutputFile =
208         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
209                                    ModuleMapFile);
210   }
211 
212   // We use createOutputFile here because this is exposed via libclang, and we
213   // must disable the RemoveFileOnSignal behavior.
214   // We use a temporary to avoid race conditions.
215   return CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
216                              /*RemoveFileOnSignal=*/false, InFile,
217                              /*Extension=*/"", /*useTemporary=*/true,
218                              /*CreateMissingDirectories=*/true);
219 }
220 
221 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
222     CompilerInstance &CI) {
223   if (!CI.getLangOpts().ModulesTS && !CI.getLangOpts().CPlusPlusModules) {
224     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
225     return false;
226   }
227 
228   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
229 
230   return GenerateModuleAction::BeginSourceFileAction(CI);
231 }
232 
233 std::unique_ptr<raw_pwrite_stream>
234 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
235                                                 StringRef InFile) {
236   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
237 }
238 
239 bool GenerateHeaderModuleAction::PrepareToExecuteAction(
240     CompilerInstance &CI) {
241   if (!CI.getLangOpts().Modules) {
242     CI.getDiagnostics().Report(diag::err_header_module_requires_modules);
243     return false;
244   }
245 
246   auto &Inputs = CI.getFrontendOpts().Inputs;
247   if (Inputs.empty())
248     return GenerateModuleAction::BeginInvocation(CI);
249 
250   auto Kind = Inputs[0].getKind();
251 
252   // Convert the header file inputs into a single module input buffer.
253   SmallString<256> HeaderContents;
254   ModuleHeaders.reserve(Inputs.size());
255   for (const FrontendInputFile &FIF : Inputs) {
256     // FIXME: We should support re-compiling from an AST file.
257     if (FIF.getKind().getFormat() != InputKind::Source || !FIF.isFile()) {
258       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
259           << (FIF.isFile() ? FIF.getFile()
260                            : FIF.getBuffer()->getBufferIdentifier());
261       return true;
262     }
263 
264     HeaderContents += "#include \"";
265     HeaderContents += FIF.getFile();
266     HeaderContents += "\"\n";
267     ModuleHeaders.push_back(FIF.getFile());
268   }
269   Buffer = llvm::MemoryBuffer::getMemBufferCopy(
270       HeaderContents, Module::getModuleInputBufferName());
271 
272   // Set that buffer up as our "real" input.
273   Inputs.clear();
274   Inputs.push_back(FrontendInputFile(Buffer.get(), Kind, /*IsSystem*/false));
275 
276   return GenerateModuleAction::PrepareToExecuteAction(CI);
277 }
278 
279 bool GenerateHeaderModuleAction::BeginSourceFileAction(
280     CompilerInstance &CI) {
281   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderModule);
282 
283   // Synthesize a Module object for the given headers.
284   auto &HS = CI.getPreprocessor().getHeaderSearchInfo();
285   SmallVector<Module::Header, 16> Headers;
286   for (StringRef Name : ModuleHeaders) {
287     const DirectoryLookup *CurDir = nullptr;
288     const FileEntry *FE = HS.LookupFile(
289         Name, SourceLocation(), /*Angled*/ false, nullptr, CurDir,
290         None, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr);
291     if (!FE) {
292       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
293         << Name;
294       continue;
295     }
296     Headers.push_back({Name, FE});
297   }
298   HS.getModuleMap().createHeaderModule(CI.getLangOpts().CurrentModule, Headers);
299 
300   return GenerateModuleAction::BeginSourceFileAction(CI);
301 }
302 
303 std::unique_ptr<raw_pwrite_stream>
304 GenerateHeaderModuleAction::CreateOutputFile(CompilerInstance &CI,
305                                              StringRef InFile) {
306   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
307 }
308 
309 SyntaxOnlyAction::~SyntaxOnlyAction() {
310 }
311 
312 std::unique_ptr<ASTConsumer>
313 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
314   return llvm::make_unique<ASTConsumer>();
315 }
316 
317 std::unique_ptr<ASTConsumer>
318 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
319                                         StringRef InFile) {
320   return llvm::make_unique<ASTConsumer>();
321 }
322 
323 std::unique_ptr<ASTConsumer>
324 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
325   return llvm::make_unique<ASTConsumer>();
326 }
327 
328 void VerifyPCHAction::ExecuteAction() {
329   CompilerInstance &CI = getCompilerInstance();
330   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
331   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
332   std::unique_ptr<ASTReader> Reader(new ASTReader(
333       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
334       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
335       Sysroot.empty() ? "" : Sysroot.c_str(),
336       /*DisableValidation*/ false,
337       /*AllowPCHWithCompilerErrors*/ false,
338       /*AllowConfigurationMismatch*/ true,
339       /*ValidateSystemInputs*/ true));
340 
341   Reader->ReadAST(getCurrentFile(),
342                   Preamble ? serialization::MK_Preamble
343                            : serialization::MK_PCH,
344                   SourceLocation(),
345                   ASTReader::ARR_ConfigurationMismatch);
346 }
347 
348 namespace {
349 struct TemplightEntry {
350   std::string Name;
351   std::string Kind;
352   std::string Event;
353   std::string DefinitionLocation;
354   std::string PointOfInstantiation;
355 };
356 } // namespace
357 
358 namespace llvm {
359 namespace yaml {
360 template <> struct MappingTraits<TemplightEntry> {
361   static void mapping(IO &io, TemplightEntry &fields) {
362     io.mapRequired("name", fields.Name);
363     io.mapRequired("kind", fields.Kind);
364     io.mapRequired("event", fields.Event);
365     io.mapRequired("orig", fields.DefinitionLocation);
366     io.mapRequired("poi", fields.PointOfInstantiation);
367   }
368 };
369 } // namespace yaml
370 } // namespace llvm
371 
372 namespace {
373 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
374   using CodeSynthesisContext = Sema::CodeSynthesisContext;
375 
376 public:
377   void initialize(const Sema &) override {}
378 
379   void finalize(const Sema &) override {}
380 
381   void atTemplateBegin(const Sema &TheSema,
382                        const CodeSynthesisContext &Inst) override {
383     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
384   }
385 
386   void atTemplateEnd(const Sema &TheSema,
387                      const CodeSynthesisContext &Inst) override {
388     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
389   }
390 
391 private:
392   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
393     switch (Kind) {
394     case CodeSynthesisContext::TemplateInstantiation:
395       return "TemplateInstantiation";
396     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
397       return "DefaultTemplateArgumentInstantiation";
398     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
399       return "DefaultFunctionArgumentInstantiation";
400     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
401       return "ExplicitTemplateArgumentSubstitution";
402     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
403       return "DeducedTemplateArgumentSubstitution";
404     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
405       return "PriorTemplateArgumentSubstitution";
406     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
407       return "DefaultTemplateArgumentChecking";
408     case CodeSynthesisContext::ExceptionSpecEvaluation:
409       return "ExceptionSpecEvaluation";
410     case CodeSynthesisContext::ExceptionSpecInstantiation:
411       return "ExceptionSpecInstantiation";
412     case CodeSynthesisContext::DeclaringSpecialMember:
413       return "DeclaringSpecialMember";
414     case CodeSynthesisContext::DefiningSynthesizedFunction:
415       return "DefiningSynthesizedFunction";
416     case CodeSynthesisContext::Memoization:
417       return "Memoization";
418     }
419     return "";
420   }
421 
422   template <bool BeginInstantiation>
423   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
424                                     const CodeSynthesisContext &Inst) {
425     std::string YAML;
426     {
427       llvm::raw_string_ostream OS(YAML);
428       llvm::yaml::Output YO(OS);
429       TemplightEntry Entry =
430           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
431       llvm::yaml::EmptyContext Context;
432       llvm::yaml::yamlize(YO, Entry, true, Context);
433     }
434     Out << "---" << YAML << "\n";
435   }
436 
437   template <bool BeginInstantiation>
438   static TemplightEntry getTemplightEntry(const Sema &TheSema,
439                                           const CodeSynthesisContext &Inst) {
440     TemplightEntry Entry;
441     Entry.Kind = toString(Inst.Kind);
442     Entry.Event = BeginInstantiation ? "Begin" : "End";
443     if (auto *NamedTemplate = dyn_cast_or_null<NamedDecl>(Inst.Entity)) {
444       llvm::raw_string_ostream OS(Entry.Name);
445       NamedTemplate->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
446       const PresumedLoc DefLoc =
447         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
448       if(!DefLoc.isInvalid())
449         Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
450                                    std::to_string(DefLoc.getLine()) + ":" +
451                                    std::to_string(DefLoc.getColumn());
452     }
453     const PresumedLoc PoiLoc =
454         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
455     if (!PoiLoc.isInvalid()) {
456       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
457                                    std::to_string(PoiLoc.getLine()) + ":" +
458                                    std::to_string(PoiLoc.getColumn());
459     }
460     return Entry;
461   }
462 };
463 } // namespace
464 
465 std::unique_ptr<ASTConsumer>
466 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
467   return llvm::make_unique<ASTConsumer>();
468 }
469 
470 void TemplightDumpAction::ExecuteAction() {
471   CompilerInstance &CI = getCompilerInstance();
472 
473   // This part is normally done by ASTFrontEndAction, but needs to happen
474   // before Templight observers can be created
475   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
476   // here so the source manager would be initialized.
477   EnsureSemaIsCreated(CI, *this);
478 
479   CI.getSema().TemplateInstCallbacks.push_back(
480       llvm::make_unique<DefaultTemplateInstCallback>());
481   ASTFrontendAction::ExecuteAction();
482 }
483 
484 namespace {
485   /// AST reader listener that dumps module information for a module
486   /// file.
487   class DumpModuleInfoListener : public ASTReaderListener {
488     llvm::raw_ostream &Out;
489 
490   public:
491     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
492 
493 #define DUMP_BOOLEAN(Value, Text)                       \
494     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
495 
496     bool ReadFullVersionInformation(StringRef FullVersion) override {
497       Out.indent(2)
498         << "Generated by "
499         << (FullVersion == getClangFullRepositoryVersion()? "this"
500                                                           : "a different")
501         << " Clang: " << FullVersion << "\n";
502       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
503     }
504 
505     void ReadModuleName(StringRef ModuleName) override {
506       Out.indent(2) << "Module name: " << ModuleName << "\n";
507     }
508     void ReadModuleMapFile(StringRef ModuleMapPath) override {
509       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
510     }
511 
512     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
513                              bool AllowCompatibleDifferences) override {
514       Out.indent(2) << "Language options:\n";
515 #define LANGOPT(Name, Bits, Default, Description) \
516       DUMP_BOOLEAN(LangOpts.Name, Description);
517 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
518       Out.indent(4) << Description << ": "                   \
519                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
520 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
521       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
522 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
523 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
524 #include "clang/Basic/LangOptions.def"
525 
526       if (!LangOpts.ModuleFeatures.empty()) {
527         Out.indent(4) << "Module features:\n";
528         for (StringRef Feature : LangOpts.ModuleFeatures)
529           Out.indent(6) << Feature << "\n";
530       }
531 
532       return false;
533     }
534 
535     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
536                            bool AllowCompatibleDifferences) override {
537       Out.indent(2) << "Target options:\n";
538       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
539       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
540       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
541 
542       if (!TargetOpts.FeaturesAsWritten.empty()) {
543         Out.indent(4) << "Target features:\n";
544         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
545              I != N; ++I) {
546           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
547         }
548       }
549 
550       return false;
551     }
552 
553     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
554                                bool Complain) override {
555       Out.indent(2) << "Diagnostic options:\n";
556 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
557 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
558       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
559 #define VALUE_DIAGOPT(Name, Bits, Default) \
560       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
561 #include "clang/Basic/DiagnosticOptions.def"
562 
563       Out.indent(4) << "Diagnostic flags:\n";
564       for (const std::string &Warning : DiagOpts->Warnings)
565         Out.indent(6) << "-W" << Warning << "\n";
566       for (const std::string &Remark : DiagOpts->Remarks)
567         Out.indent(6) << "-R" << Remark << "\n";
568 
569       return false;
570     }
571 
572     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
573                                  StringRef SpecificModuleCachePath,
574                                  bool Complain) override {
575       Out.indent(2) << "Header search options:\n";
576       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
577       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
578       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
579       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
580                    "Use builtin include directories [-nobuiltininc]");
581       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
582                    "Use standard system include directories [-nostdinc]");
583       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
584                    "Use standard C++ include directories [-nostdinc++]");
585       DUMP_BOOLEAN(HSOpts.UseLibcxx,
586                    "Use libc++ (rather than libstdc++) [-stdlib=]");
587       return false;
588     }
589 
590     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
591                                  bool Complain,
592                                  std::string &SuggestedPredefines) override {
593       Out.indent(2) << "Preprocessor options:\n";
594       DUMP_BOOLEAN(PPOpts.UsePredefines,
595                    "Uses compiler/target-specific predefines [-undef]");
596       DUMP_BOOLEAN(PPOpts.DetailedRecord,
597                    "Uses detailed preprocessing record (for indexing)");
598 
599       if (!PPOpts.Macros.empty()) {
600         Out.indent(4) << "Predefined macros:\n";
601       }
602 
603       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
604              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
605            I != IEnd; ++I) {
606         Out.indent(6);
607         if (I->second)
608           Out << "-U";
609         else
610           Out << "-D";
611         Out << I->first << "\n";
612       }
613       return false;
614     }
615 
616     /// Indicates that a particular module file extension has been read.
617     void readModuleFileExtension(
618            const ModuleFileExtensionMetadata &Metadata) override {
619       Out.indent(2) << "Module file extension '"
620                     << Metadata.BlockName << "' " << Metadata.MajorVersion
621                     << "." << Metadata.MinorVersion;
622       if (!Metadata.UserInfo.empty()) {
623         Out << ": ";
624         Out.write_escaped(Metadata.UserInfo);
625       }
626 
627       Out << "\n";
628     }
629 
630     /// Tells the \c ASTReaderListener that we want to receive the
631     /// input files of the AST file via \c visitInputFile.
632     bool needsInputFileVisitation() override { return true; }
633 
634     /// Tells the \c ASTReaderListener that we want to receive the
635     /// input files of the AST file via \c visitInputFile.
636     bool needsSystemInputFileVisitation() override { return true; }
637 
638     /// Indicates that the AST file contains particular input file.
639     ///
640     /// \returns true to continue receiving the next input file, false to stop.
641     bool visitInputFile(StringRef Filename, bool isSystem,
642                         bool isOverridden, bool isExplicitModule) override {
643 
644       Out.indent(2) << "Input file: " << Filename;
645 
646       if (isSystem || isOverridden || isExplicitModule) {
647         Out << " [";
648         if (isSystem) {
649           Out << "System";
650           if (isOverridden || isExplicitModule)
651             Out << ", ";
652         }
653         if (isOverridden) {
654           Out << "Overridden";
655           if (isExplicitModule)
656             Out << ", ";
657         }
658         if (isExplicitModule)
659           Out << "ExplicitModule";
660 
661         Out << "]";
662       }
663 
664       Out << "\n";
665 
666       return true;
667     }
668 
669     /// Returns true if this \c ASTReaderListener wants to receive the
670     /// imports of the AST file via \c visitImport, false otherwise.
671     bool needsImportVisitation() const override { return true; }
672 
673     /// If needsImportVisitation returns \c true, this is called for each
674     /// AST file imported by this AST file.
675     void visitImport(StringRef ModuleName, StringRef Filename) override {
676       Out.indent(2) << "Imports module '" << ModuleName
677                     << "': " << Filename.str() << "\n";
678     }
679 #undef DUMP_BOOLEAN
680   };
681 }
682 
683 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
684   // The Object file reader also supports raw ast files and there is no point in
685   // being strict about the module file format in -module-file-info mode.
686   CI.getHeaderSearchOpts().ModuleFormat = "obj";
687   return true;
688 }
689 
690 void DumpModuleInfoAction::ExecuteAction() {
691   // Set up the output file.
692   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
693   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
694   if (!OutputFileName.empty() && OutputFileName != "-") {
695     std::error_code EC;
696     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
697                                            llvm::sys::fs::F_Text));
698   }
699   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
700 
701   Out << "Information for module file '" << getCurrentFile() << "':\n";
702   auto &FileMgr = getCompilerInstance().getFileManager();
703   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
704   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
705   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
706                 Magic[2] == 'C' && Magic[3] == 'H');
707   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
708 
709   Preprocessor &PP = getCompilerInstance().getPreprocessor();
710   DumpModuleInfoListener Listener(Out);
711   HeaderSearchOptions &HSOpts =
712       PP.getHeaderSearchInfo().getHeaderSearchOpts();
713   ASTReader::readASTFileControlBlock(
714       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
715       /*FindModuleFileExtensions=*/true, Listener,
716       HSOpts.ModulesValidateDiagnosticOptions);
717 }
718 
719 //===----------------------------------------------------------------------===//
720 // Preprocessor Actions
721 //===----------------------------------------------------------------------===//
722 
723 void DumpRawTokensAction::ExecuteAction() {
724   Preprocessor &PP = getCompilerInstance().getPreprocessor();
725   SourceManager &SM = PP.getSourceManager();
726 
727   // Start lexing the specified input file.
728   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
729   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
730   RawLex.SetKeepWhitespaceMode(true);
731 
732   Token RawTok;
733   RawLex.LexFromRawLexer(RawTok);
734   while (RawTok.isNot(tok::eof)) {
735     PP.DumpToken(RawTok, true);
736     llvm::errs() << "\n";
737     RawLex.LexFromRawLexer(RawTok);
738   }
739 }
740 
741 void DumpTokensAction::ExecuteAction() {
742   Preprocessor &PP = getCompilerInstance().getPreprocessor();
743   // Start preprocessing the specified input file.
744   Token Tok;
745   PP.EnterMainSourceFile();
746   do {
747     PP.Lex(Tok);
748     PP.DumpToken(Tok, true);
749     llvm::errs() << "\n";
750   } while (Tok.isNot(tok::eof));
751 }
752 
753 void PreprocessOnlyAction::ExecuteAction() {
754   Preprocessor &PP = getCompilerInstance().getPreprocessor();
755 
756   // Ignore unknown pragmas.
757   PP.IgnorePragmas();
758 
759   Token Tok;
760   // Start parsing the specified input file.
761   PP.EnterMainSourceFile();
762   do {
763     PP.Lex(Tok);
764   } while (Tok.isNot(tok::eof));
765 }
766 
767 void PrintPreprocessedAction::ExecuteAction() {
768   CompilerInstance &CI = getCompilerInstance();
769   // Output file may need to be set to 'Binary', to avoid converting Unix style
770   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
771   //
772   // Look to see what type of line endings the file uses. If there's a
773   // CRLF, then we won't open the file up in binary mode. If there is
774   // just an LF or CR, then we will open the file up in binary mode.
775   // In this fashion, the output format should match the input format, unless
776   // the input format has inconsistent line endings.
777   //
778   // This should be a relatively fast operation since most files won't have
779   // all of their source code on a single line. However, that is still a
780   // concern, so if we scan for too long, we'll just assume the file should
781   // be opened in binary mode.
782   bool BinaryMode = true;
783   bool InvalidFile = false;
784   const SourceManager& SM = CI.getSourceManager();
785   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
786                                                      &InvalidFile);
787   if (!InvalidFile) {
788     const char *cur = Buffer->getBufferStart();
789     const char *end = Buffer->getBufferEnd();
790     const char *next = (cur != end) ? cur + 1 : end;
791 
792     // Limit ourselves to only scanning 256 characters into the source
793     // file.  This is mostly a sanity check in case the file has no
794     // newlines whatsoever.
795     if (end - cur > 256) end = cur + 256;
796 
797     while (next < end) {
798       if (*cur == 0x0D) {  // CR
799         if (*next == 0x0A)  // CRLF
800           BinaryMode = false;
801 
802         break;
803       } else if (*cur == 0x0A)  // LF
804         break;
805 
806       ++cur;
807       ++next;
808     }
809   }
810 
811   std::unique_ptr<raw_ostream> OS =
812       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
813   if (!OS) return;
814 
815   // If we're preprocessing a module map, start by dumping the contents of the
816   // module itself before switching to the input buffer.
817   auto &Input = getCurrentInput();
818   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
819     if (Input.isFile()) {
820       (*OS) << "# 1 \"";
821       OS->write_escaped(Input.getFile());
822       (*OS) << "\"\n";
823     }
824     getCurrentModule()->print(*OS);
825     (*OS) << "#pragma clang module contents\n";
826   }
827 
828   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
829                            CI.getPreprocessorOutputOpts());
830 }
831 
832 void PrintPreambleAction::ExecuteAction() {
833   switch (getCurrentFileKind().getLanguage()) {
834   case InputKind::C:
835   case InputKind::CXX:
836   case InputKind::ObjC:
837   case InputKind::ObjCXX:
838   case InputKind::OpenCL:
839   case InputKind::CUDA:
840   case InputKind::HIP:
841     break;
842 
843   case InputKind::Unknown:
844   case InputKind::Asm:
845   case InputKind::LLVM_IR:
846   case InputKind::RenderScript:
847     // We can't do anything with these.
848     return;
849   }
850 
851   // We don't expect to find any #include directives in a preprocessed input.
852   if (getCurrentFileKind().isPreprocessed())
853     return;
854 
855   CompilerInstance &CI = getCompilerInstance();
856   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
857   if (Buffer) {
858     unsigned Preamble =
859         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
860     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
861   }
862 }
863 
864 void DumpCompilerOptionsAction::ExecuteAction() {
865   CompilerInstance &CI = getCompilerInstance();
866   std::unique_ptr<raw_ostream> OSP =
867       CI.createDefaultOutputFile(false, getCurrentFile());
868   if (!OSP)
869     return;
870 
871   raw_ostream &OS = *OSP;
872   const Preprocessor &PP = CI.getPreprocessor();
873   const LangOptions &LangOpts = PP.getLangOpts();
874 
875   // FIXME: Rather than manually format the JSON (which is awkward due to
876   // needing to remove trailing commas), this should make use of a JSON library.
877   // FIXME: Instead of printing enums as an integral value and specifying the
878   // type as a separate field, use introspection to print the enumerator.
879 
880   OS << "{\n";
881   OS << "\n\"features\" : [\n";
882   {
883     llvm::SmallString<128> Str;
884 #define FEATURE(Name, Predicate)                                               \
885   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
886       .toVector(Str);
887 #include "clang/Basic/Features.def"
888 #undef FEATURE
889     // Remove the newline and comma from the last entry to ensure this remains
890     // valid JSON.
891     OS << Str.substr(0, Str.size() - 2);
892   }
893   OS << "\n],\n";
894 
895   OS << "\n\"extensions\" : [\n";
896   {
897     llvm::SmallString<128> Str;
898 #define EXTENSION(Name, Predicate)                                             \
899   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
900       .toVector(Str);
901 #include "clang/Basic/Features.def"
902 #undef EXTENSION
903     // Remove the newline and comma from the last entry to ensure this remains
904     // valid JSON.
905     OS << Str.substr(0, Str.size() - 2);
906   }
907   OS << "\n]\n";
908 
909   OS << "}";
910 }
911