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/Basic/LangStandard.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/DependencyDirectivesSourceMinimizer.h"
19 #include "clang/Lex/HeaderSearch.h"
20 #include "clang/Lex/Preprocessor.h"
21 #include "clang/Lex/PreprocessorOptions.h"
22 #include "clang/Sema/TemplateInstCallback.h"
23 #include "clang/Serialization/ASTReader.h"
24 #include "clang/Serialization/ASTWriter.h"
25 #include "llvm/Support/FileSystem.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/Path.h"
28 #include "llvm/Support/YAMLTraits.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <memory>
31 #include <system_error>
32 
33 using namespace clang;
34 
35 namespace {
36 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
37   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
38                                         : nullptr;
39 }
40 
41 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
42   if (Action.hasCodeCompletionSupport() &&
43       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
44     CI.createCodeCompletionConsumer();
45 
46   if (!CI.hasSema())
47     CI.createSema(Action.getTranslationUnitKind(),
48                   GetCodeCompletionConsumer(CI));
49 }
50 } // namespace
51 
52 //===----------------------------------------------------------------------===//
53 // Custom Actions
54 //===----------------------------------------------------------------------===//
55 
56 std::unique_ptr<ASTConsumer>
57 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
58   return std::make_unique<ASTConsumer>();
59 }
60 
61 void InitOnlyAction::ExecuteAction() {
62 }
63 
64 //===----------------------------------------------------------------------===//
65 // AST Consumer Actions
66 //===----------------------------------------------------------------------===//
67 
68 std::unique_ptr<ASTConsumer>
69 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
70   if (std::unique_ptr<raw_ostream> OS =
71           CI.createDefaultOutputFile(false, InFile))
72     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
73   return nullptr;
74 }
75 
76 std::unique_ptr<ASTConsumer>
77 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
78   const FrontendOptions &Opts = CI.getFrontendOpts();
79   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
80                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
81                          Opts.ASTDumpLookups, Opts.ASTDumpFormat);
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 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
96   std::string Sysroot;
97   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
98     return nullptr;
99 
100   std::string OutputFile;
101   std::unique_ptr<raw_pwrite_stream> OS =
102       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
103   if (!OS)
104     return nullptr;
105 
106   if (!CI.getFrontendOpts().RelocatablePCH)
107     Sysroot.clear();
108 
109   const auto &FrontendOpts = CI.getFrontendOpts();
110   auto Buffer = std::make_shared<PCHBuffer>();
111   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
112   Consumers.push_back(std::make_unique<PCHGenerator>(
113       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
114       FrontendOpts.ModuleFileExtensions,
115       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
116       FrontendOpts.IncludeTimestamps, +CI.getLangOpts().CacheGeneratedPCH));
117   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
118       CI, InFile, OutputFile, std::move(OS), Buffer));
119 
120   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
121 }
122 
123 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
124                                                     std::string &Sysroot) {
125   Sysroot = CI.getHeaderSearchOpts().Sysroot;
126   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
127     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
128     return false;
129   }
130 
131   return true;
132 }
133 
134 std::unique_ptr<llvm::raw_pwrite_stream>
135 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
136                                     std::string &OutputFile) {
137   // We use createOutputFile here because this is exposed via libclang, and we
138   // must disable the RemoveFileOnSignal behavior.
139   // We use a temporary to avoid race conditions.
140   std::unique_ptr<raw_pwrite_stream> OS =
141       CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
142                           /*RemoveFileOnSignal=*/false, InFile,
143                           /*Extension=*/"", /*UseTemporary=*/true);
144   if (!OS)
145     return nullptr;
146 
147   OutputFile = CI.getFrontendOpts().OutputFile;
148   return OS;
149 }
150 
151 bool GeneratePCHAction::shouldEraseOutputFiles() {
152   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
153     return false;
154   return ASTFrontendAction::shouldEraseOutputFiles();
155 }
156 
157 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
158   CI.getLangOpts().CompilingPCH = true;
159   return true;
160 }
161 
162 std::unique_ptr<ASTConsumer>
163 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
164                                         StringRef InFile) {
165   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
166   if (!OS)
167     return nullptr;
168 
169   std::string OutputFile = CI.getFrontendOpts().OutputFile;
170   std::string Sysroot;
171 
172   auto Buffer = std::make_shared<PCHBuffer>();
173   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
174 
175   Consumers.push_back(std::make_unique<PCHGenerator>(
176       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
177       CI.getFrontendOpts().ModuleFileExtensions,
178       /*AllowASTWithErrors=*/false,
179       /*IncludeTimestamps=*/
180       +CI.getFrontendOpts().BuildingImplicitModule,
181       /*ShouldCacheASTInMemory=*/
182       +CI.getFrontendOpts().BuildingImplicitModule));
183   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
184       CI, InFile, OutputFile, std::move(OS), Buffer));
185   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
186 }
187 
188 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
189     CompilerInstance &CI) {
190   if (!CI.getLangOpts().Modules) {
191     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
192     return false;
193   }
194 
195   return GenerateModuleAction::BeginSourceFileAction(CI);
196 }
197 
198 std::unique_ptr<raw_pwrite_stream>
199 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
200                                                     StringRef InFile) {
201   // If no output file was provided, figure out where this module would go
202   // in the module cache.
203   if (CI.getFrontendOpts().OutputFile.empty()) {
204     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
205     if (ModuleMapFile.empty())
206       ModuleMapFile = InFile;
207 
208     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
209     CI.getFrontendOpts().OutputFile =
210         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
211                                    ModuleMapFile);
212   }
213 
214   // We use createOutputFile here because this is exposed via libclang, and we
215   // must disable the RemoveFileOnSignal behavior.
216   // We use a temporary to avoid race conditions.
217   return CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
218                              /*RemoveFileOnSignal=*/false, InFile,
219                              /*Extension=*/"", /*UseTemporary=*/true,
220                              /*CreateMissingDirectories=*/true);
221 }
222 
223 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
224     CompilerInstance &CI) {
225   if (!CI.getLangOpts().ModulesTS && !CI.getLangOpts().CPlusPlusModules) {
226     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
227     return false;
228   }
229 
230   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
231 
232   return GenerateModuleAction::BeginSourceFileAction(CI);
233 }
234 
235 std::unique_ptr<raw_pwrite_stream>
236 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
237                                                 StringRef InFile) {
238   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
239 }
240 
241 bool GenerateHeaderModuleAction::PrepareToExecuteAction(
242     CompilerInstance &CI) {
243   if (!CI.getLangOpts().Modules) {
244     CI.getDiagnostics().Report(diag::err_header_module_requires_modules);
245     return false;
246   }
247 
248   auto &Inputs = CI.getFrontendOpts().Inputs;
249   if (Inputs.empty())
250     return GenerateModuleAction::BeginInvocation(CI);
251 
252   auto Kind = Inputs[0].getKind();
253 
254   // Convert the header file inputs into a single module input buffer.
255   SmallString<256> HeaderContents;
256   ModuleHeaders.reserve(Inputs.size());
257   for (const FrontendInputFile &FIF : Inputs) {
258     // FIXME: We should support re-compiling from an AST file.
259     if (FIF.getKind().getFormat() != InputKind::Source || !FIF.isFile()) {
260       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
261           << (FIF.isFile() ? FIF.getFile()
262                            : FIF.getBuffer()->getBufferIdentifier());
263       return true;
264     }
265 
266     HeaderContents += "#include \"";
267     HeaderContents += FIF.getFile();
268     HeaderContents += "\"\n";
269     ModuleHeaders.push_back(FIF.getFile());
270   }
271   Buffer = llvm::MemoryBuffer::getMemBufferCopy(
272       HeaderContents, Module::getModuleInputBufferName());
273 
274   // Set that buffer up as our "real" input.
275   Inputs.clear();
276   Inputs.push_back(FrontendInputFile(Buffer.get(), Kind, /*IsSystem*/false));
277 
278   return GenerateModuleAction::PrepareToExecuteAction(CI);
279 }
280 
281 bool GenerateHeaderModuleAction::BeginSourceFileAction(
282     CompilerInstance &CI) {
283   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderModule);
284 
285   // Synthesize a Module object for the given headers.
286   auto &HS = CI.getPreprocessor().getHeaderSearchInfo();
287   SmallVector<Module::Header, 16> Headers;
288   for (StringRef Name : ModuleHeaders) {
289     const DirectoryLookup *CurDir = nullptr;
290     const FileEntry *FE = HS.LookupFile(
291         Name, SourceLocation(), /*Angled*/ false, nullptr, CurDir,
292         None, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr);
293     if (!FE) {
294       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
295         << Name;
296       continue;
297     }
298     Headers.push_back({Name, FE});
299   }
300   HS.getModuleMap().createHeaderModule(CI.getLangOpts().CurrentModule, Headers);
301 
302   return GenerateModuleAction::BeginSourceFileAction(CI);
303 }
304 
305 std::unique_ptr<raw_pwrite_stream>
306 GenerateHeaderModuleAction::CreateOutputFile(CompilerInstance &CI,
307                                              StringRef InFile) {
308   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
309 }
310 
311 SyntaxOnlyAction::~SyntaxOnlyAction() {
312 }
313 
314 std::unique_ptr<ASTConsumer>
315 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
316   return std::make_unique<ASTConsumer>();
317 }
318 
319 std::unique_ptr<ASTConsumer>
320 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
321                                         StringRef InFile) {
322   return std::make_unique<ASTConsumer>();
323 }
324 
325 std::unique_ptr<ASTConsumer>
326 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
327   return std::make_unique<ASTConsumer>();
328 }
329 
330 void VerifyPCHAction::ExecuteAction() {
331   CompilerInstance &CI = getCompilerInstance();
332   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
333   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
334   std::unique_ptr<ASTReader> Reader(new ASTReader(
335       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
336       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
337       Sysroot.empty() ? "" : Sysroot.c_str(),
338       /*DisableValidation*/ false,
339       /*AllowPCHWithCompilerErrors*/ false,
340       /*AllowConfigurationMismatch*/ true,
341       /*ValidateSystemInputs*/ true));
342 
343   Reader->ReadAST(getCurrentFile(),
344                   Preamble ? serialization::MK_Preamble
345                            : serialization::MK_PCH,
346                   SourceLocation(),
347                   ASTReader::ARR_ConfigurationMismatch);
348 }
349 
350 namespace {
351 struct TemplightEntry {
352   std::string Name;
353   std::string Kind;
354   std::string Event;
355   std::string DefinitionLocation;
356   std::string PointOfInstantiation;
357 };
358 } // namespace
359 
360 namespace llvm {
361 namespace yaml {
362 template <> struct MappingTraits<TemplightEntry> {
363   static void mapping(IO &io, TemplightEntry &fields) {
364     io.mapRequired("name", fields.Name);
365     io.mapRequired("kind", fields.Kind);
366     io.mapRequired("event", fields.Event);
367     io.mapRequired("orig", fields.DefinitionLocation);
368     io.mapRequired("poi", fields.PointOfInstantiation);
369   }
370 };
371 } // namespace yaml
372 } // namespace llvm
373 
374 namespace {
375 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
376   using CodeSynthesisContext = Sema::CodeSynthesisContext;
377 
378 public:
379   void initialize(const Sema &) override {}
380 
381   void finalize(const Sema &) override {}
382 
383   void atTemplateBegin(const Sema &TheSema,
384                        const CodeSynthesisContext &Inst) override {
385     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
386   }
387 
388   void atTemplateEnd(const Sema &TheSema,
389                      const CodeSynthesisContext &Inst) override {
390     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
391   }
392 
393 private:
394   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
395     switch (Kind) {
396     case CodeSynthesisContext::TemplateInstantiation:
397       return "TemplateInstantiation";
398     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
399       return "DefaultTemplateArgumentInstantiation";
400     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
401       return "DefaultFunctionArgumentInstantiation";
402     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
403       return "ExplicitTemplateArgumentSubstitution";
404     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
405       return "DeducedTemplateArgumentSubstitution";
406     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
407       return "PriorTemplateArgumentSubstitution";
408     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
409       return "DefaultTemplateArgumentChecking";
410     case CodeSynthesisContext::ExceptionSpecEvaluation:
411       return "ExceptionSpecEvaluation";
412     case CodeSynthesisContext::ExceptionSpecInstantiation:
413       return "ExceptionSpecInstantiation";
414     case CodeSynthesisContext::DeclaringSpecialMember:
415       return "DeclaringSpecialMember";
416     case CodeSynthesisContext::DefiningSynthesizedFunction:
417       return "DefiningSynthesizedFunction";
418     case CodeSynthesisContext::Memoization:
419       return "Memoization";
420     }
421     return "";
422   }
423 
424   template <bool BeginInstantiation>
425   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
426                                     const CodeSynthesisContext &Inst) {
427     std::string YAML;
428     {
429       llvm::raw_string_ostream OS(YAML);
430       llvm::yaml::Output YO(OS);
431       TemplightEntry Entry =
432           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
433       llvm::yaml::EmptyContext Context;
434       llvm::yaml::yamlize(YO, Entry, true, Context);
435     }
436     Out << "---" << YAML << "\n";
437   }
438 
439   template <bool BeginInstantiation>
440   static TemplightEntry getTemplightEntry(const Sema &TheSema,
441                                           const CodeSynthesisContext &Inst) {
442     TemplightEntry Entry;
443     Entry.Kind = toString(Inst.Kind);
444     Entry.Event = BeginInstantiation ? "Begin" : "End";
445     if (auto *NamedTemplate = dyn_cast_or_null<NamedDecl>(Inst.Entity)) {
446       llvm::raw_string_ostream OS(Entry.Name);
447       NamedTemplate->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
448       const PresumedLoc DefLoc =
449         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
450       if(!DefLoc.isInvalid())
451         Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
452                                    std::to_string(DefLoc.getLine()) + ":" +
453                                    std::to_string(DefLoc.getColumn());
454     }
455     const PresumedLoc PoiLoc =
456         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
457     if (!PoiLoc.isInvalid()) {
458       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
459                                    std::to_string(PoiLoc.getLine()) + ":" +
460                                    std::to_string(PoiLoc.getColumn());
461     }
462     return Entry;
463   }
464 };
465 } // namespace
466 
467 std::unique_ptr<ASTConsumer>
468 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
469   return std::make_unique<ASTConsumer>();
470 }
471 
472 void TemplightDumpAction::ExecuteAction() {
473   CompilerInstance &CI = getCompilerInstance();
474 
475   // This part is normally done by ASTFrontEndAction, but needs to happen
476   // before Templight observers can be created
477   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
478   // here so the source manager would be initialized.
479   EnsureSemaIsCreated(CI, *this);
480 
481   CI.getSema().TemplateInstCallbacks.push_back(
482       std::make_unique<DefaultTemplateInstCallback>());
483   ASTFrontendAction::ExecuteAction();
484 }
485 
486 namespace {
487   /// AST reader listener that dumps module information for a module
488   /// file.
489   class DumpModuleInfoListener : public ASTReaderListener {
490     llvm::raw_ostream &Out;
491 
492   public:
493     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
494 
495 #define DUMP_BOOLEAN(Value, Text)                       \
496     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
497 
498     bool ReadFullVersionInformation(StringRef FullVersion) override {
499       Out.indent(2)
500         << "Generated by "
501         << (FullVersion == getClangFullRepositoryVersion()? "this"
502                                                           : "a different")
503         << " Clang: " << FullVersion << "\n";
504       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
505     }
506 
507     void ReadModuleName(StringRef ModuleName) override {
508       Out.indent(2) << "Module name: " << ModuleName << "\n";
509     }
510     void ReadModuleMapFile(StringRef ModuleMapPath) override {
511       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
512     }
513 
514     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
515                              bool AllowCompatibleDifferences) override {
516       Out.indent(2) << "Language options:\n";
517 #define LANGOPT(Name, Bits, Default, Description) \
518       DUMP_BOOLEAN(LangOpts.Name, Description);
519 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
520       Out.indent(4) << Description << ": "                   \
521                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
522 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
523       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
524 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
525 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
526 #include "clang/Basic/LangOptions.def"
527 
528       if (!LangOpts.ModuleFeatures.empty()) {
529         Out.indent(4) << "Module features:\n";
530         for (StringRef Feature : LangOpts.ModuleFeatures)
531           Out.indent(6) << Feature << "\n";
532       }
533 
534       return false;
535     }
536 
537     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
538                            bool AllowCompatibleDifferences) override {
539       Out.indent(2) << "Target options:\n";
540       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
541       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
542       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
543 
544       if (!TargetOpts.FeaturesAsWritten.empty()) {
545         Out.indent(4) << "Target features:\n";
546         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
547              I != N; ++I) {
548           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
549         }
550       }
551 
552       return false;
553     }
554 
555     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
556                                bool Complain) override {
557       Out.indent(2) << "Diagnostic options:\n";
558 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
559 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
560       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
561 #define VALUE_DIAGOPT(Name, Bits, Default) \
562       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
563 #include "clang/Basic/DiagnosticOptions.def"
564 
565       Out.indent(4) << "Diagnostic flags:\n";
566       for (const std::string &Warning : DiagOpts->Warnings)
567         Out.indent(6) << "-W" << Warning << "\n";
568       for (const std::string &Remark : DiagOpts->Remarks)
569         Out.indent(6) << "-R" << Remark << "\n";
570 
571       return false;
572     }
573 
574     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
575                                  StringRef SpecificModuleCachePath,
576                                  bool Complain) override {
577       Out.indent(2) << "Header search options:\n";
578       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
579       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
580       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
581       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
582                    "Use builtin include directories [-nobuiltininc]");
583       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
584                    "Use standard system include directories [-nostdinc]");
585       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
586                    "Use standard C++ include directories [-nostdinc++]");
587       DUMP_BOOLEAN(HSOpts.UseLibcxx,
588                    "Use libc++ (rather than libstdc++) [-stdlib=]");
589       return false;
590     }
591 
592     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
593                                  bool Complain,
594                                  std::string &SuggestedPredefines) override {
595       Out.indent(2) << "Preprocessor options:\n";
596       DUMP_BOOLEAN(PPOpts.UsePredefines,
597                    "Uses compiler/target-specific predefines [-undef]");
598       DUMP_BOOLEAN(PPOpts.DetailedRecord,
599                    "Uses detailed preprocessing record (for indexing)");
600 
601       if (!PPOpts.Macros.empty()) {
602         Out.indent(4) << "Predefined macros:\n";
603       }
604 
605       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
606              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
607            I != IEnd; ++I) {
608         Out.indent(6);
609         if (I->second)
610           Out << "-U";
611         else
612           Out << "-D";
613         Out << I->first << "\n";
614       }
615       return false;
616     }
617 
618     /// Indicates that a particular module file extension has been read.
619     void readModuleFileExtension(
620            const ModuleFileExtensionMetadata &Metadata) override {
621       Out.indent(2) << "Module file extension '"
622                     << Metadata.BlockName << "' " << Metadata.MajorVersion
623                     << "." << Metadata.MinorVersion;
624       if (!Metadata.UserInfo.empty()) {
625         Out << ": ";
626         Out.write_escaped(Metadata.UserInfo);
627       }
628 
629       Out << "\n";
630     }
631 
632     /// Tells the \c ASTReaderListener that we want to receive the
633     /// input files of the AST file via \c visitInputFile.
634     bool needsInputFileVisitation() override { return true; }
635 
636     /// Tells the \c ASTReaderListener that we want to receive the
637     /// input files of the AST file via \c visitInputFile.
638     bool needsSystemInputFileVisitation() override { return true; }
639 
640     /// Indicates that the AST file contains particular input file.
641     ///
642     /// \returns true to continue receiving the next input file, false to stop.
643     bool visitInputFile(StringRef Filename, bool isSystem,
644                         bool isOverridden, bool isExplicitModule) override {
645 
646       Out.indent(2) << "Input file: " << Filename;
647 
648       if (isSystem || isOverridden || isExplicitModule) {
649         Out << " [";
650         if (isSystem) {
651           Out << "System";
652           if (isOverridden || isExplicitModule)
653             Out << ", ";
654         }
655         if (isOverridden) {
656           Out << "Overridden";
657           if (isExplicitModule)
658             Out << ", ";
659         }
660         if (isExplicitModule)
661           Out << "ExplicitModule";
662 
663         Out << "]";
664       }
665 
666       Out << "\n";
667 
668       return true;
669     }
670 
671     /// Returns true if this \c ASTReaderListener wants to receive the
672     /// imports of the AST file via \c visitImport, false otherwise.
673     bool needsImportVisitation() const override { return true; }
674 
675     /// If needsImportVisitation returns \c true, this is called for each
676     /// AST file imported by this AST file.
677     void visitImport(StringRef ModuleName, StringRef Filename) override {
678       Out.indent(2) << "Imports module '" << ModuleName
679                     << "': " << Filename.str() << "\n";
680     }
681 #undef DUMP_BOOLEAN
682   };
683 }
684 
685 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
686   // The Object file reader also supports raw ast files and there is no point in
687   // being strict about the module file format in -module-file-info mode.
688   CI.getHeaderSearchOpts().ModuleFormat = "obj";
689   return true;
690 }
691 
692 void DumpModuleInfoAction::ExecuteAction() {
693   // Set up the output file.
694   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
695   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
696   if (!OutputFileName.empty() && OutputFileName != "-") {
697     std::error_code EC;
698     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
699                                            llvm::sys::fs::OF_Text));
700   }
701   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
702 
703   Out << "Information for module file '" << getCurrentFile() << "':\n";
704   auto &FileMgr = getCompilerInstance().getFileManager();
705   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
706   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
707   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
708                 Magic[2] == 'C' && Magic[3] == 'H');
709   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
710 
711   Preprocessor &PP = getCompilerInstance().getPreprocessor();
712   DumpModuleInfoListener Listener(Out);
713   HeaderSearchOptions &HSOpts =
714       PP.getHeaderSearchInfo().getHeaderSearchOpts();
715   ASTReader::readASTFileControlBlock(
716       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
717       /*FindModuleFileExtensions=*/true, Listener,
718       HSOpts.ModulesValidateDiagnosticOptions);
719 }
720 
721 //===----------------------------------------------------------------------===//
722 // Preprocessor Actions
723 //===----------------------------------------------------------------------===//
724 
725 void DumpRawTokensAction::ExecuteAction() {
726   Preprocessor &PP = getCompilerInstance().getPreprocessor();
727   SourceManager &SM = PP.getSourceManager();
728 
729   // Start lexing the specified input file.
730   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
731   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
732   RawLex.SetKeepWhitespaceMode(true);
733 
734   Token RawTok;
735   RawLex.LexFromRawLexer(RawTok);
736   while (RawTok.isNot(tok::eof)) {
737     PP.DumpToken(RawTok, true);
738     llvm::errs() << "\n";
739     RawLex.LexFromRawLexer(RawTok);
740   }
741 }
742 
743 void DumpTokensAction::ExecuteAction() {
744   Preprocessor &PP = getCompilerInstance().getPreprocessor();
745   // Start preprocessing the specified input file.
746   Token Tok;
747   PP.EnterMainSourceFile();
748   do {
749     PP.Lex(Tok);
750     PP.DumpToken(Tok, true);
751     llvm::errs() << "\n";
752   } while (Tok.isNot(tok::eof));
753 }
754 
755 void PreprocessOnlyAction::ExecuteAction() {
756   Preprocessor &PP = getCompilerInstance().getPreprocessor();
757 
758   // Ignore unknown pragmas.
759   PP.IgnorePragmas();
760 
761   Token Tok;
762   // Start parsing the specified input file.
763   PP.EnterMainSourceFile();
764   do {
765     PP.Lex(Tok);
766   } while (Tok.isNot(tok::eof));
767 }
768 
769 void PrintPreprocessedAction::ExecuteAction() {
770   CompilerInstance &CI = getCompilerInstance();
771   // Output file may need to be set to 'Binary', to avoid converting Unix style
772   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
773   //
774   // Look to see what type of line endings the file uses. If there's a
775   // CRLF, then we won't open the file up in binary mode. If there is
776   // just an LF or CR, then we will open the file up in binary mode.
777   // In this fashion, the output format should match the input format, unless
778   // the input format has inconsistent line endings.
779   //
780   // This should be a relatively fast operation since most files won't have
781   // all of their source code on a single line. However, that is still a
782   // concern, so if we scan for too long, we'll just assume the file should
783   // be opened in binary mode.
784   bool BinaryMode = true;
785   bool InvalidFile = false;
786   const SourceManager& SM = CI.getSourceManager();
787   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
788                                                      &InvalidFile);
789   if (!InvalidFile) {
790     const char *cur = Buffer->getBufferStart();
791     const char *end = Buffer->getBufferEnd();
792     const char *next = (cur != end) ? cur + 1 : end;
793 
794     // Limit ourselves to only scanning 256 characters into the source
795     // file.  This is mostly a sanity check in case the file has no
796     // newlines whatsoever.
797     if (end - cur > 256) end = cur + 256;
798 
799     while (next < end) {
800       if (*cur == 0x0D) {  // CR
801         if (*next == 0x0A)  // CRLF
802           BinaryMode = false;
803 
804         break;
805       } else if (*cur == 0x0A)  // LF
806         break;
807 
808       ++cur;
809       ++next;
810     }
811   }
812 
813   std::unique_ptr<raw_ostream> OS =
814       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
815   if (!OS) return;
816 
817   // If we're preprocessing a module map, start by dumping the contents of the
818   // module itself before switching to the input buffer.
819   auto &Input = getCurrentInput();
820   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
821     if (Input.isFile()) {
822       (*OS) << "# 1 \"";
823       OS->write_escaped(Input.getFile());
824       (*OS) << "\"\n";
825     }
826     getCurrentModule()->print(*OS);
827     (*OS) << "#pragma clang module contents\n";
828   }
829 
830   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
831                            CI.getPreprocessorOutputOpts());
832 }
833 
834 void PrintPreambleAction::ExecuteAction() {
835   switch (getCurrentFileKind().getLanguage()) {
836   case Language::C:
837   case Language::CXX:
838   case Language::ObjC:
839   case Language::ObjCXX:
840   case Language::OpenCL:
841   case Language::CUDA:
842   case Language::HIP:
843     break;
844 
845   case Language::Unknown:
846   case Language::Asm:
847   case Language::LLVM_IR:
848   case Language::RenderScript:
849     // We can't do anything with these.
850     return;
851   }
852 
853   // We don't expect to find any #include directives in a preprocessed input.
854   if (getCurrentFileKind().isPreprocessed())
855     return;
856 
857   CompilerInstance &CI = getCompilerInstance();
858   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
859   if (Buffer) {
860     unsigned Preamble =
861         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
862     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
863   }
864 }
865 
866 void DumpCompilerOptionsAction::ExecuteAction() {
867   CompilerInstance &CI = getCompilerInstance();
868   std::unique_ptr<raw_ostream> OSP =
869       CI.createDefaultOutputFile(false, getCurrentFile());
870   if (!OSP)
871     return;
872 
873   raw_ostream &OS = *OSP;
874   const Preprocessor &PP = CI.getPreprocessor();
875   const LangOptions &LangOpts = PP.getLangOpts();
876 
877   // FIXME: Rather than manually format the JSON (which is awkward due to
878   // needing to remove trailing commas), this should make use of a JSON library.
879   // FIXME: Instead of printing enums as an integral value and specifying the
880   // type as a separate field, use introspection to print the enumerator.
881 
882   OS << "{\n";
883   OS << "\n\"features\" : [\n";
884   {
885     llvm::SmallString<128> Str;
886 #define FEATURE(Name, Predicate)                                               \
887   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
888       .toVector(Str);
889 #include "clang/Basic/Features.def"
890 #undef FEATURE
891     // Remove the newline and comma from the last entry to ensure this remains
892     // valid JSON.
893     OS << Str.substr(0, Str.size() - 2);
894   }
895   OS << "\n],\n";
896 
897   OS << "\n\"extensions\" : [\n";
898   {
899     llvm::SmallString<128> Str;
900 #define EXTENSION(Name, Predicate)                                             \
901   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
902       .toVector(Str);
903 #include "clang/Basic/Features.def"
904 #undef EXTENSION
905     // Remove the newline and comma from the last entry to ensure this remains
906     // valid JSON.
907     OS << Str.substr(0, Str.size() - 2);
908   }
909   OS << "\n]\n";
910 
911   OS << "}";
912 }
913 
914 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
915   CompilerInstance &CI = getCompilerInstance();
916   SourceManager &SM = CI.getPreprocessor().getSourceManager();
917   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
918 
919   llvm::SmallString<1024> Output;
920   llvm::SmallVector<minimize_source_to_dependency_directives::Token, 32> Toks;
921   if (minimizeSourceToDependencyDirectives(
922           FromFile->getBuffer(), Output, Toks, &CI.getDiagnostics(),
923           SM.getLocForStartOfFile(SM.getMainFileID()))) {
924     assert(CI.getDiagnostics().hasErrorOccurred() &&
925            "no errors reported for failure");
926 
927     // Preprocess the source when verifying the diagnostics to capture the
928     // 'expected' comments.
929     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
930       // Make sure we don't emit new diagnostics!
931       CI.getDiagnostics().setSuppressAllDiagnostics();
932       Preprocessor &PP = getCompilerInstance().getPreprocessor();
933       PP.EnterMainSourceFile();
934       Token Tok;
935       do {
936         PP.Lex(Tok);
937       } while (Tok.isNot(tok::eof));
938     }
939     return;
940   }
941   llvm::outs() << Output;
942 }
943