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/AST/Decl.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Basic/LangStandard.h"
14 #include "clang/Basic/Module.h"
15 #include "clang/Basic/TargetInfo.h"
16 #include "clang/Frontend/ASTConsumers.h"
17 #include "clang/Frontend/CompilerInstance.h"
18 #include "clang/Frontend/FrontendDiagnostic.h"
19 #include "clang/Frontend/MultiplexConsumer.h"
20 #include "clang/Frontend/Utils.h"
21 #include "clang/Lex/DependencyDirectivesSourceMinimizer.h"
22 #include "clang/Lex/HeaderSearch.h"
23 #include "clang/Lex/Preprocessor.h"
24 #include "clang/Lex/PreprocessorOptions.h"
25 #include "clang/Sema/TemplateInstCallback.h"
26 #include "clang/Serialization/ASTReader.h"
27 #include "clang/Serialization/ASTWriter.h"
28 #include "clang/Serialization/ModuleFile.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/FileSystem.h"
31 #include "llvm/Support/MemoryBuffer.h"
32 #include "llvm/Support/Path.h"
33 #include "llvm/Support/YAMLTraits.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include <memory>
36 #include <system_error>
37 
38 using namespace clang;
39 
40 namespace {
41 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
42   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
43                                         : nullptr;
44 }
45 
46 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
47   if (Action.hasCodeCompletionSupport() &&
48       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
49     CI.createCodeCompletionConsumer();
50 
51   if (!CI.hasSema())
52     CI.createSema(Action.getTranslationUnitKind(),
53                   GetCodeCompletionConsumer(CI));
54 }
55 } // namespace
56 
57 //===----------------------------------------------------------------------===//
58 // Custom Actions
59 //===----------------------------------------------------------------------===//
60 
61 std::unique_ptr<ASTConsumer>
62 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
63   return std::make_unique<ASTConsumer>();
64 }
65 
66 void InitOnlyAction::ExecuteAction() {
67 }
68 
69 // Basically PreprocessOnlyAction::ExecuteAction.
70 void ReadPCHAndPreprocessAction::ExecuteAction() {
71   Preprocessor &PP = getCompilerInstance().getPreprocessor();
72 
73   // Ignore unknown pragmas.
74   PP.IgnorePragmas();
75 
76   Token Tok;
77   // Start parsing the specified input file.
78   PP.EnterMainSourceFile();
79   do {
80     PP.Lex(Tok);
81   } while (Tok.isNot(tok::eof));
82 }
83 
84 std::unique_ptr<ASTConsumer>
85 ReadPCHAndPreprocessAction::CreateASTConsumer(CompilerInstance &CI,
86                                               StringRef InFile) {
87   return std::make_unique<ASTConsumer>();
88 }
89 
90 //===----------------------------------------------------------------------===//
91 // AST Consumer Actions
92 //===----------------------------------------------------------------------===//
93 
94 std::unique_ptr<ASTConsumer>
95 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
96   if (std::unique_ptr<raw_ostream> OS =
97           CI.createDefaultOutputFile(false, InFile))
98     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
99   return nullptr;
100 }
101 
102 std::unique_ptr<ASTConsumer>
103 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
104   const FrontendOptions &Opts = CI.getFrontendOpts();
105   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
106                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
107                          Opts.ASTDumpLookups, Opts.ASTDumpDeclTypes,
108                          Opts.ASTDumpFormat);
109 }
110 
111 std::unique_ptr<ASTConsumer>
112 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
113   return CreateASTDeclNodeLister();
114 }
115 
116 std::unique_ptr<ASTConsumer>
117 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
118   return CreateASTViewer();
119 }
120 
121 std::unique_ptr<ASTConsumer>
122 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
123   std::string Sysroot;
124   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
125     return nullptr;
126 
127   std::string OutputFile;
128   std::unique_ptr<raw_pwrite_stream> OS =
129       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
130   if (!OS)
131     return nullptr;
132 
133   if (!CI.getFrontendOpts().RelocatablePCH)
134     Sysroot.clear();
135 
136   const auto &FrontendOpts = CI.getFrontendOpts();
137   auto Buffer = std::make_shared<PCHBuffer>();
138   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
139   Consumers.push_back(std::make_unique<PCHGenerator>(
140       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
141       FrontendOpts.ModuleFileExtensions,
142       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
143       FrontendOpts.IncludeTimestamps, +CI.getLangOpts().CacheGeneratedPCH));
144   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
145       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
146 
147   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
148 }
149 
150 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
151                                                     std::string &Sysroot) {
152   Sysroot = CI.getHeaderSearchOpts().Sysroot;
153   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
154     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
155     return false;
156   }
157 
158   return true;
159 }
160 
161 std::unique_ptr<llvm::raw_pwrite_stream>
162 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
163                                     std::string &OutputFile) {
164   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
165   std::unique_ptr<raw_pwrite_stream> OS = CI.createDefaultOutputFile(
166       /*Binary=*/true, InFile, /*Extension=*/"", /*RemoveFileOnSignal=*/false);
167   if (!OS)
168     return nullptr;
169 
170   OutputFile = CI.getFrontendOpts().OutputFile;
171   return OS;
172 }
173 
174 bool GeneratePCHAction::shouldEraseOutputFiles() {
175   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
176     return false;
177   return ASTFrontendAction::shouldEraseOutputFiles();
178 }
179 
180 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
181   CI.getLangOpts().CompilingPCH = true;
182   return true;
183 }
184 
185 std::unique_ptr<ASTConsumer>
186 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
187                                         StringRef InFile) {
188   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
189   if (!OS)
190     return nullptr;
191 
192   std::string OutputFile = CI.getFrontendOpts().OutputFile;
193   std::string Sysroot;
194 
195   auto Buffer = std::make_shared<PCHBuffer>();
196   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
197 
198   Consumers.push_back(std::make_unique<PCHGenerator>(
199       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
200       CI.getFrontendOpts().ModuleFileExtensions,
201       /*AllowASTWithErrors=*/
202       +CI.getFrontendOpts().AllowPCMWithCompilerErrors,
203       /*IncludeTimestamps=*/
204       +CI.getFrontendOpts().BuildingImplicitModule,
205       /*ShouldCacheASTInMemory=*/
206       +CI.getFrontendOpts().BuildingImplicitModule));
207   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
208       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
209   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
210 }
211 
212 bool GenerateModuleAction::shouldEraseOutputFiles() {
213   return !getCompilerInstance().getFrontendOpts().AllowPCMWithCompilerErrors &&
214          ASTFrontendAction::shouldEraseOutputFiles();
215 }
216 
217 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
218     CompilerInstance &CI) {
219   if (!CI.getLangOpts().Modules) {
220     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
221     return false;
222   }
223 
224   return GenerateModuleAction::BeginSourceFileAction(CI);
225 }
226 
227 std::unique_ptr<raw_pwrite_stream>
228 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
229                                                     StringRef InFile) {
230   // If no output file was provided, figure out where this module would go
231   // in the module cache.
232   if (CI.getFrontendOpts().OutputFile.empty()) {
233     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
234     if (ModuleMapFile.empty())
235       ModuleMapFile = InFile;
236 
237     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
238     CI.getFrontendOpts().OutputFile =
239         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
240                                    ModuleMapFile);
241   }
242 
243   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
244   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, /*Extension=*/"",
245                                     /*RemoveFileOnSignal=*/false,
246                                     /*CreateMissingDirectories=*/true,
247                                     /*ForceUseTemporary=*/true);
248 }
249 
250 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
251     CompilerInstance &CI) {
252   if (!CI.getLangOpts().ModulesTS && !CI.getLangOpts().CPlusPlusModules) {
253     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
254     return false;
255   }
256 
257   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
258 
259   return GenerateModuleAction::BeginSourceFileAction(CI);
260 }
261 
262 std::unique_ptr<raw_pwrite_stream>
263 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
264                                                 StringRef InFile) {
265   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
266 }
267 
268 bool GenerateHeaderModuleAction::PrepareToExecuteAction(
269     CompilerInstance &CI) {
270   if (!CI.getLangOpts().Modules) {
271     CI.getDiagnostics().Report(diag::err_header_module_requires_modules);
272     return false;
273   }
274 
275   auto &Inputs = CI.getFrontendOpts().Inputs;
276   if (Inputs.empty())
277     return GenerateModuleAction::BeginInvocation(CI);
278 
279   auto Kind = Inputs[0].getKind();
280 
281   // Convert the header file inputs into a single module input buffer.
282   SmallString<256> HeaderContents;
283   ModuleHeaders.reserve(Inputs.size());
284   for (const FrontendInputFile &FIF : Inputs) {
285     // FIXME: We should support re-compiling from an AST file.
286     if (FIF.getKind().getFormat() != InputKind::Source || !FIF.isFile()) {
287       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
288           << (FIF.isFile() ? FIF.getFile()
289                            : FIF.getBuffer().getBufferIdentifier());
290       return true;
291     }
292 
293     HeaderContents += "#include \"";
294     HeaderContents += FIF.getFile();
295     HeaderContents += "\"\n";
296     ModuleHeaders.push_back(std::string(FIF.getFile()));
297   }
298   Buffer = llvm::MemoryBuffer::getMemBufferCopy(
299       HeaderContents, Module::getModuleInputBufferName());
300 
301   // Set that buffer up as our "real" input.
302   Inputs.clear();
303   Inputs.push_back(
304       FrontendInputFile(Buffer->getMemBufferRef(), Kind, /*IsSystem*/ false));
305 
306   return GenerateModuleAction::PrepareToExecuteAction(CI);
307 }
308 
309 bool GenerateHeaderModuleAction::BeginSourceFileAction(
310     CompilerInstance &CI) {
311   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderModule);
312 
313   // Synthesize a Module object for the given headers.
314   auto &HS = CI.getPreprocessor().getHeaderSearchInfo();
315   SmallVector<Module::Header, 16> Headers;
316   for (StringRef Name : ModuleHeaders) {
317     Optional<FileEntryRef> FE = HS.LookupFile(
318         Name, SourceLocation(), /*Angled*/ false, nullptr, nullptr, None,
319         nullptr, nullptr, nullptr, nullptr, nullptr, nullptr);
320     if (!FE) {
321       CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
322         << Name;
323       continue;
324     }
325     Headers.push_back(
326         {std::string(Name), std::string(Name), &FE->getFileEntry()});
327   }
328   HS.getModuleMap().createHeaderModule(CI.getLangOpts().CurrentModule, Headers);
329 
330   return GenerateModuleAction::BeginSourceFileAction(CI);
331 }
332 
333 std::unique_ptr<raw_pwrite_stream>
334 GenerateHeaderModuleAction::CreateOutputFile(CompilerInstance &CI,
335                                              StringRef InFile) {
336   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
337 }
338 
339 bool GenerateHeaderUnitAction::BeginSourceFileAction(CompilerInstance &CI) {
340   if (!CI.getLangOpts().CPlusPlusModules) {
341     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
342     return false;
343   }
344   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderUnit);
345   return GenerateModuleAction::BeginSourceFileAction(CI);
346 }
347 
348 std::unique_ptr<raw_pwrite_stream>
349 GenerateHeaderUnitAction::CreateOutputFile(CompilerInstance &CI,
350                                            StringRef InFile) {
351   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
352 }
353 
354 SyntaxOnlyAction::~SyntaxOnlyAction() {
355 }
356 
357 std::unique_ptr<ASTConsumer>
358 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
359   return std::make_unique<ASTConsumer>();
360 }
361 
362 std::unique_ptr<ASTConsumer>
363 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
364                                         StringRef InFile) {
365   return std::make_unique<ASTConsumer>();
366 }
367 
368 std::unique_ptr<ASTConsumer>
369 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
370   return std::make_unique<ASTConsumer>();
371 }
372 
373 void VerifyPCHAction::ExecuteAction() {
374   CompilerInstance &CI = getCompilerInstance();
375   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
376   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
377   std::unique_ptr<ASTReader> Reader(new ASTReader(
378       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
379       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
380       Sysroot.empty() ? "" : Sysroot.c_str(),
381       DisableValidationForModuleKind::None,
382       /*AllowASTWithCompilerErrors*/ false,
383       /*AllowConfigurationMismatch*/ true,
384       /*ValidateSystemInputs*/ true));
385 
386   Reader->ReadAST(getCurrentFile(),
387                   Preamble ? serialization::MK_Preamble
388                            : serialization::MK_PCH,
389                   SourceLocation(),
390                   ASTReader::ARR_ConfigurationMismatch);
391 }
392 
393 namespace {
394 struct TemplightEntry {
395   std::string Name;
396   std::string Kind;
397   std::string Event;
398   std::string DefinitionLocation;
399   std::string PointOfInstantiation;
400 };
401 } // namespace
402 
403 namespace llvm {
404 namespace yaml {
405 template <> struct MappingTraits<TemplightEntry> {
406   static void mapping(IO &io, TemplightEntry &fields) {
407     io.mapRequired("name", fields.Name);
408     io.mapRequired("kind", fields.Kind);
409     io.mapRequired("event", fields.Event);
410     io.mapRequired("orig", fields.DefinitionLocation);
411     io.mapRequired("poi", fields.PointOfInstantiation);
412   }
413 };
414 } // namespace yaml
415 } // namespace llvm
416 
417 namespace {
418 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
419   using CodeSynthesisContext = Sema::CodeSynthesisContext;
420 
421 public:
422   void initialize(const Sema &) override {}
423 
424   void finalize(const Sema &) override {}
425 
426   void atTemplateBegin(const Sema &TheSema,
427                        const CodeSynthesisContext &Inst) override {
428     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
429   }
430 
431   void atTemplateEnd(const Sema &TheSema,
432                      const CodeSynthesisContext &Inst) override {
433     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
434   }
435 
436 private:
437   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
438     switch (Kind) {
439     case CodeSynthesisContext::TemplateInstantiation:
440       return "TemplateInstantiation";
441     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
442       return "DefaultTemplateArgumentInstantiation";
443     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
444       return "DefaultFunctionArgumentInstantiation";
445     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
446       return "ExplicitTemplateArgumentSubstitution";
447     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
448       return "DeducedTemplateArgumentSubstitution";
449     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
450       return "PriorTemplateArgumentSubstitution";
451     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
452       return "DefaultTemplateArgumentChecking";
453     case CodeSynthesisContext::ExceptionSpecEvaluation:
454       return "ExceptionSpecEvaluation";
455     case CodeSynthesisContext::ExceptionSpecInstantiation:
456       return "ExceptionSpecInstantiation";
457     case CodeSynthesisContext::DeclaringSpecialMember:
458       return "DeclaringSpecialMember";
459     case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
460       return "DeclaringImplicitEqualityComparison";
461     case CodeSynthesisContext::DefiningSynthesizedFunction:
462       return "DefiningSynthesizedFunction";
463     case CodeSynthesisContext::RewritingOperatorAsSpaceship:
464       return "RewritingOperatorAsSpaceship";
465     case CodeSynthesisContext::Memoization:
466       return "Memoization";
467     case CodeSynthesisContext::ConstraintsCheck:
468       return "ConstraintsCheck";
469     case CodeSynthesisContext::ConstraintSubstitution:
470       return "ConstraintSubstitution";
471     case CodeSynthesisContext::ConstraintNormalization:
472       return "ConstraintNormalization";
473     case CodeSynthesisContext::ParameterMappingSubstitution:
474       return "ParameterMappingSubstitution";
475     case CodeSynthesisContext::RequirementInstantiation:
476       return "RequirementInstantiation";
477     case CodeSynthesisContext::NestedRequirementConstraintsCheck:
478       return "NestedRequirementConstraintsCheck";
479     case CodeSynthesisContext::InitializingStructuredBinding:
480       return "InitializingStructuredBinding";
481     case CodeSynthesisContext::MarkingClassDllexported:
482       return "MarkingClassDllexported";
483     }
484     return "";
485   }
486 
487   template <bool BeginInstantiation>
488   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
489                                     const CodeSynthesisContext &Inst) {
490     std::string YAML;
491     {
492       llvm::raw_string_ostream OS(YAML);
493       llvm::yaml::Output YO(OS);
494       TemplightEntry Entry =
495           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
496       llvm::yaml::EmptyContext Context;
497       llvm::yaml::yamlize(YO, Entry, true, Context);
498     }
499     Out << "---" << YAML << "\n";
500   }
501 
502   static void printEntryName(const Sema &TheSema, const Decl *Entity,
503                              llvm::raw_string_ostream &OS) {
504     auto *NamedTemplate = cast<NamedDecl>(Entity);
505 
506     PrintingPolicy Policy = TheSema.Context.getPrintingPolicy();
507     // FIXME: Also ask for FullyQualifiedNames?
508     Policy.SuppressDefaultTemplateArgs = false;
509     NamedTemplate->getNameForDiagnostic(OS, Policy, true);
510 
511     if (!OS.str().empty())
512       return;
513 
514     Decl *Ctx = Decl::castFromDeclContext(NamedTemplate->getDeclContext());
515     NamedDecl *NamedCtx = dyn_cast_or_null<NamedDecl>(Ctx);
516 
517     if (const auto *Decl = dyn_cast<TagDecl>(NamedTemplate)) {
518       if (const auto *R = dyn_cast<RecordDecl>(Decl)) {
519         if (R->isLambda()) {
520           OS << "lambda at ";
521           Decl->getLocation().print(OS, TheSema.getSourceManager());
522           return;
523         }
524       }
525       OS << "unnamed " << Decl->getKindName();
526       return;
527     }
528 
529     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
530       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
531          << " ";
532       if (Decl->getFunctionScopeDepth() > 0)
533         OS << "(at depth " << Decl->getFunctionScopeDepth() << ") ";
534       OS << "of ";
535       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
536       return;
537     }
538 
539     if (const auto *Decl = dyn_cast<TemplateTypeParmDecl>(NamedTemplate)) {
540       if (const Type *Ty = Decl->getTypeForDecl()) {
541         if (const auto *TTPT = dyn_cast_or_null<TemplateTypeParmType>(Ty)) {
542           OS << "unnamed template type parameter " << TTPT->getIndex() << " ";
543           if (TTPT->getDepth() > 0)
544             OS << "(at depth " << TTPT->getDepth() << ") ";
545           OS << "of ";
546           NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
547           return;
548         }
549       }
550     }
551 
552     if (const auto *Decl = dyn_cast<NonTypeTemplateParmDecl>(NamedTemplate)) {
553       OS << "unnamed template non-type parameter " << Decl->getIndex() << " ";
554       if (Decl->getDepth() > 0)
555         OS << "(at depth " << Decl->getDepth() << ") ";
556       OS << "of ";
557       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
558       return;
559     }
560 
561     if (const auto *Decl = dyn_cast<TemplateTemplateParmDecl>(NamedTemplate)) {
562       OS << "unnamed template template parameter " << Decl->getIndex() << " ";
563       if (Decl->getDepth() > 0)
564         OS << "(at depth " << Decl->getDepth() << ") ";
565       OS << "of ";
566       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
567       return;
568     }
569 
570     llvm_unreachable("Failed to retrieve a name for this entry!");
571     OS << "unnamed identifier";
572   }
573 
574   template <bool BeginInstantiation>
575   static TemplightEntry getTemplightEntry(const Sema &TheSema,
576                                           const CodeSynthesisContext &Inst) {
577     TemplightEntry Entry;
578     Entry.Kind = toString(Inst.Kind);
579     Entry.Event = BeginInstantiation ? "Begin" : "End";
580     llvm::raw_string_ostream OS(Entry.Name);
581     printEntryName(TheSema, Inst.Entity, OS);
582     const PresumedLoc DefLoc =
583         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
584     if (!DefLoc.isInvalid())
585       Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
586                                  std::to_string(DefLoc.getLine()) + ":" +
587                                  std::to_string(DefLoc.getColumn());
588     const PresumedLoc PoiLoc =
589         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
590     if (!PoiLoc.isInvalid()) {
591       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
592                                    std::to_string(PoiLoc.getLine()) + ":" +
593                                    std::to_string(PoiLoc.getColumn());
594     }
595     return Entry;
596   }
597 };
598 } // namespace
599 
600 std::unique_ptr<ASTConsumer>
601 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
602   return std::make_unique<ASTConsumer>();
603 }
604 
605 void TemplightDumpAction::ExecuteAction() {
606   CompilerInstance &CI = getCompilerInstance();
607 
608   // This part is normally done by ASTFrontEndAction, but needs to happen
609   // before Templight observers can be created
610   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
611   // here so the source manager would be initialized.
612   EnsureSemaIsCreated(CI, *this);
613 
614   CI.getSema().TemplateInstCallbacks.push_back(
615       std::make_unique<DefaultTemplateInstCallback>());
616   ASTFrontendAction::ExecuteAction();
617 }
618 
619 namespace {
620   /// AST reader listener that dumps module information for a module
621   /// file.
622   class DumpModuleInfoListener : public ASTReaderListener {
623     llvm::raw_ostream &Out;
624 
625   public:
626     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
627 
628 #define DUMP_BOOLEAN(Value, Text)                       \
629     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
630 
631     bool ReadFullVersionInformation(StringRef FullVersion) override {
632       Out.indent(2)
633         << "Generated by "
634         << (FullVersion == getClangFullRepositoryVersion()? "this"
635                                                           : "a different")
636         << " Clang: " << FullVersion << "\n";
637       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
638     }
639 
640     void ReadModuleName(StringRef ModuleName) override {
641       Out.indent(2) << "Module name: " << ModuleName << "\n";
642     }
643     void ReadModuleMapFile(StringRef ModuleMapPath) override {
644       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
645     }
646 
647     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
648                              bool AllowCompatibleDifferences) override {
649       Out.indent(2) << "Language options:\n";
650 #define LANGOPT(Name, Bits, Default, Description) \
651       DUMP_BOOLEAN(LangOpts.Name, Description);
652 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
653       Out.indent(4) << Description << ": "                   \
654                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
655 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
656       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
657 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
658 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
659 #include "clang/Basic/LangOptions.def"
660 
661       if (!LangOpts.ModuleFeatures.empty()) {
662         Out.indent(4) << "Module features:\n";
663         for (StringRef Feature : LangOpts.ModuleFeatures)
664           Out.indent(6) << Feature << "\n";
665       }
666 
667       return false;
668     }
669 
670     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
671                            bool AllowCompatibleDifferences) override {
672       Out.indent(2) << "Target options:\n";
673       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
674       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
675       Out.indent(4) << "  TuneCPU: " << TargetOpts.TuneCPU << "\n";
676       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
677 
678       if (!TargetOpts.FeaturesAsWritten.empty()) {
679         Out.indent(4) << "Target features:\n";
680         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
681              I != N; ++I) {
682           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
683         }
684       }
685 
686       return false;
687     }
688 
689     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
690                                bool Complain) override {
691       Out.indent(2) << "Diagnostic options:\n";
692 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
693 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
694       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
695 #define VALUE_DIAGOPT(Name, Bits, Default) \
696       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
697 #include "clang/Basic/DiagnosticOptions.def"
698 
699       Out.indent(4) << "Diagnostic flags:\n";
700       for (const std::string &Warning : DiagOpts->Warnings)
701         Out.indent(6) << "-W" << Warning << "\n";
702       for (const std::string &Remark : DiagOpts->Remarks)
703         Out.indent(6) << "-R" << Remark << "\n";
704 
705       return false;
706     }
707 
708     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
709                                  StringRef SpecificModuleCachePath,
710                                  bool Complain) override {
711       Out.indent(2) << "Header search options:\n";
712       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
713       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
714       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
715       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
716                    "Use builtin include directories [-nobuiltininc]");
717       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
718                    "Use standard system include directories [-nostdinc]");
719       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
720                    "Use standard C++ include directories [-nostdinc++]");
721       DUMP_BOOLEAN(HSOpts.UseLibcxx,
722                    "Use libc++ (rather than libstdc++) [-stdlib=]");
723       return false;
724     }
725 
726     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
727                                  bool Complain,
728                                  std::string &SuggestedPredefines) override {
729       Out.indent(2) << "Preprocessor options:\n";
730       DUMP_BOOLEAN(PPOpts.UsePredefines,
731                    "Uses compiler/target-specific predefines [-undef]");
732       DUMP_BOOLEAN(PPOpts.DetailedRecord,
733                    "Uses detailed preprocessing record (for indexing)");
734 
735       if (!PPOpts.Macros.empty()) {
736         Out.indent(4) << "Predefined macros:\n";
737       }
738 
739       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
740              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
741            I != IEnd; ++I) {
742         Out.indent(6);
743         if (I->second)
744           Out << "-U";
745         else
746           Out << "-D";
747         Out << I->first << "\n";
748       }
749       return false;
750     }
751 
752     /// Indicates that a particular module file extension has been read.
753     void readModuleFileExtension(
754            const ModuleFileExtensionMetadata &Metadata) override {
755       Out.indent(2) << "Module file extension '"
756                     << Metadata.BlockName << "' " << Metadata.MajorVersion
757                     << "." << Metadata.MinorVersion;
758       if (!Metadata.UserInfo.empty()) {
759         Out << ": ";
760         Out.write_escaped(Metadata.UserInfo);
761       }
762 
763       Out << "\n";
764     }
765 
766     /// Tells the \c ASTReaderListener that we want to receive the
767     /// input files of the AST file via \c visitInputFile.
768     bool needsInputFileVisitation() override { return true; }
769 
770     /// Tells the \c ASTReaderListener that we want to receive the
771     /// input files of the AST file via \c visitInputFile.
772     bool needsSystemInputFileVisitation() override { return true; }
773 
774     /// Indicates that the AST file contains particular input file.
775     ///
776     /// \returns true to continue receiving the next input file, false to stop.
777     bool visitInputFile(StringRef Filename, bool isSystem,
778                         bool isOverridden, bool isExplicitModule) override {
779 
780       Out.indent(2) << "Input file: " << Filename;
781 
782       if (isSystem || isOverridden || isExplicitModule) {
783         Out << " [";
784         if (isSystem) {
785           Out << "System";
786           if (isOverridden || isExplicitModule)
787             Out << ", ";
788         }
789         if (isOverridden) {
790           Out << "Overridden";
791           if (isExplicitModule)
792             Out << ", ";
793         }
794         if (isExplicitModule)
795           Out << "ExplicitModule";
796 
797         Out << "]";
798       }
799 
800       Out << "\n";
801 
802       return true;
803     }
804 
805     /// Returns true if this \c ASTReaderListener wants to receive the
806     /// imports of the AST file via \c visitImport, false otherwise.
807     bool needsImportVisitation() const override { return true; }
808 
809     /// If needsImportVisitation returns \c true, this is called for each
810     /// AST file imported by this AST file.
811     void visitImport(StringRef ModuleName, StringRef Filename) override {
812       Out.indent(2) << "Imports module '" << ModuleName
813                     << "': " << Filename.str() << "\n";
814     }
815 #undef DUMP_BOOLEAN
816   };
817 }
818 
819 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
820   // The Object file reader also supports raw ast files and there is no point in
821   // being strict about the module file format in -module-file-info mode.
822   CI.getHeaderSearchOpts().ModuleFormat = "obj";
823   return true;
824 }
825 
826 static StringRef ModuleKindName(Module::ModuleKind MK) {
827   switch (MK) {
828   case Module::ModuleMapModule:
829     return "Module Map Module";
830   case Module::ModuleInterfaceUnit:
831     return "Interface Unit";
832   case Module::ModulePartitionInterface:
833     return "Partition Interface";
834   case Module::ModulePartitionImplementation:
835     return "Partition Implementation";
836   case Module::ModuleHeaderUnit:
837     return "Header Unit";
838   case Module::GlobalModuleFragment:
839     return "Global Module Fragment";
840   case Module::PrivateModuleFragment:
841     return "Private Module Fragment";
842   }
843   llvm_unreachable("unknown module kind!");
844 }
845 
846 void DumpModuleInfoAction::ExecuteAction() {
847   assert(isCurrentFileAST() && "dumping non-AST?");
848   // Set up the output file.
849   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
850   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
851   if (!OutputFileName.empty() && OutputFileName != "-") {
852     std::error_code EC;
853     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
854                                            llvm::sys::fs::OF_TextWithCRLF));
855   }
856   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
857 
858   Out << "Information for module file '" << getCurrentFile() << "':\n";
859   auto &FileMgr = getCompilerInstance().getFileManager();
860   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
861   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
862   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
863                 Magic[2] == 'C' && Magic[3] == 'H');
864   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
865 
866   Preprocessor &PP = getCompilerInstance().getPreprocessor();
867   DumpModuleInfoListener Listener(Out);
868   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
869 
870   // The FrontendAction::BeginSourceFile () method loads the AST so that much
871   // of the information is already available and modules should have been
872   // loaded.
873 
874   const LangOptions &LO = getCurrentASTUnit().getLangOpts();
875   if (LO.CPlusPlusModules && !LO.CurrentModule.empty()) {
876 
877     ASTReader *R = getCurrentASTUnit().getASTReader().get();
878     unsigned SubModuleCount = R->getTotalNumSubmodules();
879     serialization::ModuleFile &MF = R->getModuleManager().getPrimaryModule();
880     Out << "  ====== C++20 Module structure ======\n";
881 
882     if (MF.ModuleName != LO.CurrentModule)
883       Out << "  Mismatched module names : " << MF.ModuleName << " and "
884           << LO.CurrentModule << "\n";
885 
886     struct SubModInfo {
887       unsigned Idx;
888       Module *Mod;
889       Module::ModuleKind Kind;
890       std::string &Name;
891       bool Seen;
892     };
893     std::map<std::string, SubModInfo> SubModMap;
894     auto PrintSubMapEntry = [&](std::string Name, Module::ModuleKind Kind) {
895       Out << "    " << ModuleKindName(Kind) << " '" << Name << "'";
896       auto I = SubModMap.find(Name);
897       if (I == SubModMap.end())
898         Out << " was not found in the sub modules!\n";
899       else {
900         I->second.Seen = true;
901         Out << " is at index #" << I->second.Idx << "\n";
902       }
903     };
904     Module *Primary = nullptr;
905     for (unsigned Idx = 0; Idx <= SubModuleCount; ++Idx) {
906       Module *M = R->getModule(Idx);
907       if (!M)
908         continue;
909       if (M->Name == LO.CurrentModule) {
910         Primary = M;
911         Out << "  " << ModuleKindName(M->Kind) << " '" << LO.CurrentModule
912             << "' is the Primary Module at index #" << Idx << "\n";
913         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, true}});
914       } else
915         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, false}});
916     }
917     if (Primary) {
918       if (!Primary->submodules().empty())
919         Out << "   Sub Modules:\n";
920       for (auto MI : Primary->submodules()) {
921         PrintSubMapEntry(MI->Name, MI->Kind);
922       }
923       if (!Primary->Imports.empty())
924         Out << "   Imports:\n";
925       for (auto IMP : Primary->Imports) {
926         PrintSubMapEntry(IMP->Name, IMP->Kind);
927       }
928       if (!Primary->Exports.empty())
929         Out << "   Exports:\n";
930       for (unsigned MN = 0, N = Primary->Exports.size(); MN != N; ++MN) {
931         if (Module *M = Primary->Exports[MN].getPointer()) {
932           PrintSubMapEntry(M->Name, M->Kind);
933         }
934       }
935     }
936     // Now let's print out any modules we did not see as part of the Primary.
937     for (auto SM : SubModMap) {
938       if (!SM.second.Seen && SM.second.Mod) {
939         Out << "  " << ModuleKindName(SM.second.Kind) << " '" << SM.first
940             << "' at index #" << SM.second.Idx
941             << " has no direct reference in the Primary\n";
942       }
943     }
944     Out << "  ====== ======\n";
945   }
946 
947   // The reminder of the output is produced from the listener as the AST
948   // FileCcontrolBlock is (re-)parsed.
949   ASTReader::readASTFileControlBlock(
950       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
951       /*FindModuleFileExtensions=*/true, Listener,
952       HSOpts.ModulesValidateDiagnosticOptions);
953 }
954 
955 //===----------------------------------------------------------------------===//
956 // Preprocessor Actions
957 //===----------------------------------------------------------------------===//
958 
959 void DumpRawTokensAction::ExecuteAction() {
960   Preprocessor &PP = getCompilerInstance().getPreprocessor();
961   SourceManager &SM = PP.getSourceManager();
962 
963   // Start lexing the specified input file.
964   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
965   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
966   RawLex.SetKeepWhitespaceMode(true);
967 
968   Token RawTok;
969   RawLex.LexFromRawLexer(RawTok);
970   while (RawTok.isNot(tok::eof)) {
971     PP.DumpToken(RawTok, true);
972     llvm::errs() << "\n";
973     RawLex.LexFromRawLexer(RawTok);
974   }
975 }
976 
977 void DumpTokensAction::ExecuteAction() {
978   Preprocessor &PP = getCompilerInstance().getPreprocessor();
979   // Start preprocessing the specified input file.
980   Token Tok;
981   PP.EnterMainSourceFile();
982   do {
983     PP.Lex(Tok);
984     PP.DumpToken(Tok, true);
985     llvm::errs() << "\n";
986   } while (Tok.isNot(tok::eof));
987 }
988 
989 void PreprocessOnlyAction::ExecuteAction() {
990   Preprocessor &PP = getCompilerInstance().getPreprocessor();
991 
992   // Ignore unknown pragmas.
993   PP.IgnorePragmas();
994 
995   Token Tok;
996   // Start parsing the specified input file.
997   PP.EnterMainSourceFile();
998   do {
999     PP.Lex(Tok);
1000   } while (Tok.isNot(tok::eof));
1001 }
1002 
1003 void PrintPreprocessedAction::ExecuteAction() {
1004   CompilerInstance &CI = getCompilerInstance();
1005   // Output file may need to be set to 'Binary', to avoid converting Unix style
1006   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>) on Windows.
1007   //
1008   // Look to see what type of line endings the file uses. If there's a
1009   // CRLF, then we won't open the file up in binary mode. If there is
1010   // just an LF or CR, then we will open the file up in binary mode.
1011   // In this fashion, the output format should match the input format, unless
1012   // the input format has inconsistent line endings.
1013   //
1014   // This should be a relatively fast operation since most files won't have
1015   // all of their source code on a single line. However, that is still a
1016   // concern, so if we scan for too long, we'll just assume the file should
1017   // be opened in binary mode.
1018 
1019   bool BinaryMode = false;
1020   if (llvm::Triple(LLVM_HOST_TRIPLE).isOSWindows()) {
1021     BinaryMode = true;
1022     const SourceManager &SM = CI.getSourceManager();
1023     if (llvm::Optional<llvm::MemoryBufferRef> Buffer =
1024             SM.getBufferOrNone(SM.getMainFileID())) {
1025       const char *cur = Buffer->getBufferStart();
1026       const char *end = Buffer->getBufferEnd();
1027       const char *next = (cur != end) ? cur + 1 : end;
1028 
1029       // Limit ourselves to only scanning 256 characters into the source
1030       // file.  This is mostly a check in case the file has no
1031       // newlines whatsoever.
1032       if (end - cur > 256)
1033         end = cur + 256;
1034 
1035       while (next < end) {
1036         if (*cur == 0x0D) {  // CR
1037           if (*next == 0x0A) // CRLF
1038             BinaryMode = false;
1039 
1040           break;
1041         } else if (*cur == 0x0A) // LF
1042           break;
1043 
1044         ++cur;
1045         ++next;
1046       }
1047     }
1048   }
1049 
1050   std::unique_ptr<raw_ostream> OS =
1051       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
1052   if (!OS) return;
1053 
1054   // If we're preprocessing a module map, start by dumping the contents of the
1055   // module itself before switching to the input buffer.
1056   auto &Input = getCurrentInput();
1057   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
1058     if (Input.isFile()) {
1059       (*OS) << "# 1 \"";
1060       OS->write_escaped(Input.getFile());
1061       (*OS) << "\"\n";
1062     }
1063     getCurrentModule()->print(*OS);
1064     (*OS) << "#pragma clang module contents\n";
1065   }
1066 
1067   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
1068                            CI.getPreprocessorOutputOpts());
1069 }
1070 
1071 void PrintPreambleAction::ExecuteAction() {
1072   switch (getCurrentFileKind().getLanguage()) {
1073   case Language::C:
1074   case Language::CXX:
1075   case Language::ObjC:
1076   case Language::ObjCXX:
1077   case Language::OpenCL:
1078   case Language::OpenCLCXX:
1079   case Language::CUDA:
1080   case Language::HIP:
1081   case Language::HLSL:
1082     break;
1083 
1084   case Language::Unknown:
1085   case Language::Asm:
1086   case Language::LLVM_IR:
1087   case Language::RenderScript:
1088     // We can't do anything with these.
1089     return;
1090   }
1091 
1092   // We don't expect to find any #include directives in a preprocessed input.
1093   if (getCurrentFileKind().isPreprocessed())
1094     return;
1095 
1096   CompilerInstance &CI = getCompilerInstance();
1097   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
1098   if (Buffer) {
1099     unsigned Preamble =
1100         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
1101     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
1102   }
1103 }
1104 
1105 void DumpCompilerOptionsAction::ExecuteAction() {
1106   CompilerInstance &CI = getCompilerInstance();
1107   std::unique_ptr<raw_ostream> OSP =
1108       CI.createDefaultOutputFile(false, getCurrentFile());
1109   if (!OSP)
1110     return;
1111 
1112   raw_ostream &OS = *OSP;
1113   const Preprocessor &PP = CI.getPreprocessor();
1114   const LangOptions &LangOpts = PP.getLangOpts();
1115 
1116   // FIXME: Rather than manually format the JSON (which is awkward due to
1117   // needing to remove trailing commas), this should make use of a JSON library.
1118   // FIXME: Instead of printing enums as an integral value and specifying the
1119   // type as a separate field, use introspection to print the enumerator.
1120 
1121   OS << "{\n";
1122   OS << "\n\"features\" : [\n";
1123   {
1124     llvm::SmallString<128> Str;
1125 #define FEATURE(Name, Predicate)                                               \
1126   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1127       .toVector(Str);
1128 #include "clang/Basic/Features.def"
1129 #undef FEATURE
1130     // Remove the newline and comma from the last entry to ensure this remains
1131     // valid JSON.
1132     OS << Str.substr(0, Str.size() - 2);
1133   }
1134   OS << "\n],\n";
1135 
1136   OS << "\n\"extensions\" : [\n";
1137   {
1138     llvm::SmallString<128> Str;
1139 #define EXTENSION(Name, Predicate)                                             \
1140   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1141       .toVector(Str);
1142 #include "clang/Basic/Features.def"
1143 #undef EXTENSION
1144     // Remove the newline and comma from the last entry to ensure this remains
1145     // valid JSON.
1146     OS << Str.substr(0, Str.size() - 2);
1147   }
1148   OS << "\n]\n";
1149 
1150   OS << "}";
1151 }
1152 
1153 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
1154   CompilerInstance &CI = getCompilerInstance();
1155   SourceManager &SM = CI.getPreprocessor().getSourceManager();
1156   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
1157 
1158   llvm::SmallString<1024> Output;
1159   llvm::SmallVector<minimize_source_to_dependency_directives::Token, 32> Toks;
1160   if (minimizeSourceToDependencyDirectives(
1161           FromFile.getBuffer(), Output, Toks, &CI.getDiagnostics(),
1162           SM.getLocForStartOfFile(SM.getMainFileID()))) {
1163     assert(CI.getDiagnostics().hasErrorOccurred() &&
1164            "no errors reported for failure");
1165 
1166     // Preprocess the source when verifying the diagnostics to capture the
1167     // 'expected' comments.
1168     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
1169       // Make sure we don't emit new diagnostics!
1170       CI.getDiagnostics().setSuppressAllDiagnostics(true);
1171       Preprocessor &PP = getCompilerInstance().getPreprocessor();
1172       PP.EnterMainSourceFile();
1173       Token Tok;
1174       do {
1175         PP.Lex(Tok);
1176       } while (Tok.isNot(tok::eof));
1177     }
1178     return;
1179   }
1180   llvm::outs() << Output;
1181 }
1182 
1183 void GetDependenciesByModuleNameAction::ExecuteAction() {
1184   CompilerInstance &CI = getCompilerInstance();
1185   Preprocessor &PP = CI.getPreprocessor();
1186   SourceManager &SM = PP.getSourceManager();
1187   FileID MainFileID = SM.getMainFileID();
1188   SourceLocation FileStart = SM.getLocForStartOfFile(MainFileID);
1189   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1190   IdentifierInfo *ModuleID = PP.getIdentifierInfo(ModuleName);
1191   Path.push_back(std::make_pair(ModuleID, FileStart));
1192   auto ModResult = CI.loadModule(FileStart, Path, Module::Hidden, false);
1193   PPCallbacks *CB = PP.getPPCallbacks();
1194   CB->moduleImport(SourceLocation(), Path, ModResult);
1195 }
1196