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/DependencyDirectivesScanner.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     case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
484       return "BuildingBuiltinDumpStructCall";
485     }
486     return "";
487   }
488 
489   template <bool BeginInstantiation>
490   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
491                                     const CodeSynthesisContext &Inst) {
492     std::string YAML;
493     {
494       llvm::raw_string_ostream OS(YAML);
495       llvm::yaml::Output YO(OS);
496       TemplightEntry Entry =
497           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
498       llvm::yaml::EmptyContext Context;
499       llvm::yaml::yamlize(YO, Entry, true, Context);
500     }
501     Out << "---" << YAML << "\n";
502   }
503 
504   static void printEntryName(const Sema &TheSema, const Decl *Entity,
505                              llvm::raw_string_ostream &OS) {
506     auto *NamedTemplate = cast<NamedDecl>(Entity);
507 
508     PrintingPolicy Policy = TheSema.Context.getPrintingPolicy();
509     // FIXME: Also ask for FullyQualifiedNames?
510     Policy.SuppressDefaultTemplateArgs = false;
511     NamedTemplate->getNameForDiagnostic(OS, Policy, true);
512 
513     if (!OS.str().empty())
514       return;
515 
516     Decl *Ctx = Decl::castFromDeclContext(NamedTemplate->getDeclContext());
517     NamedDecl *NamedCtx = dyn_cast_or_null<NamedDecl>(Ctx);
518 
519     if (const auto *Decl = dyn_cast<TagDecl>(NamedTemplate)) {
520       if (const auto *R = dyn_cast<RecordDecl>(Decl)) {
521         if (R->isLambda()) {
522           OS << "lambda at ";
523           Decl->getLocation().print(OS, TheSema.getSourceManager());
524           return;
525         }
526       }
527       OS << "unnamed " << Decl->getKindName();
528       return;
529     }
530 
531     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
532       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
533          << " ";
534       if (Decl->getFunctionScopeDepth() > 0)
535         OS << "(at depth " << Decl->getFunctionScopeDepth() << ") ";
536       OS << "of ";
537       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
538       return;
539     }
540 
541     if (const auto *Decl = dyn_cast<TemplateTypeParmDecl>(NamedTemplate)) {
542       if (const Type *Ty = Decl->getTypeForDecl()) {
543         if (const auto *TTPT = dyn_cast_or_null<TemplateTypeParmType>(Ty)) {
544           OS << "unnamed template type parameter " << TTPT->getIndex() << " ";
545           if (TTPT->getDepth() > 0)
546             OS << "(at depth " << TTPT->getDepth() << ") ";
547           OS << "of ";
548           NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
549           return;
550         }
551       }
552     }
553 
554     if (const auto *Decl = dyn_cast<NonTypeTemplateParmDecl>(NamedTemplate)) {
555       OS << "unnamed template non-type parameter " << Decl->getIndex() << " ";
556       if (Decl->getDepth() > 0)
557         OS << "(at depth " << Decl->getDepth() << ") ";
558       OS << "of ";
559       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
560       return;
561     }
562 
563     if (const auto *Decl = dyn_cast<TemplateTemplateParmDecl>(NamedTemplate)) {
564       OS << "unnamed template template parameter " << Decl->getIndex() << " ";
565       if (Decl->getDepth() > 0)
566         OS << "(at depth " << Decl->getDepth() << ") ";
567       OS << "of ";
568       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
569       return;
570     }
571 
572     llvm_unreachable("Failed to retrieve a name for this entry!");
573     OS << "unnamed identifier";
574   }
575 
576   template <bool BeginInstantiation>
577   static TemplightEntry getTemplightEntry(const Sema &TheSema,
578                                           const CodeSynthesisContext &Inst) {
579     TemplightEntry Entry;
580     Entry.Kind = toString(Inst.Kind);
581     Entry.Event = BeginInstantiation ? "Begin" : "End";
582     llvm::raw_string_ostream OS(Entry.Name);
583     printEntryName(TheSema, Inst.Entity, OS);
584     const PresumedLoc DefLoc =
585         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
586     if (!DefLoc.isInvalid())
587       Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
588                                  std::to_string(DefLoc.getLine()) + ":" +
589                                  std::to_string(DefLoc.getColumn());
590     const PresumedLoc PoiLoc =
591         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
592     if (!PoiLoc.isInvalid()) {
593       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
594                                    std::to_string(PoiLoc.getLine()) + ":" +
595                                    std::to_string(PoiLoc.getColumn());
596     }
597     return Entry;
598   }
599 };
600 } // namespace
601 
602 std::unique_ptr<ASTConsumer>
603 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
604   return std::make_unique<ASTConsumer>();
605 }
606 
607 void TemplightDumpAction::ExecuteAction() {
608   CompilerInstance &CI = getCompilerInstance();
609 
610   // This part is normally done by ASTFrontEndAction, but needs to happen
611   // before Templight observers can be created
612   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
613   // here so the source manager would be initialized.
614   EnsureSemaIsCreated(CI, *this);
615 
616   CI.getSema().TemplateInstCallbacks.push_back(
617       std::make_unique<DefaultTemplateInstCallback>());
618   ASTFrontendAction::ExecuteAction();
619 }
620 
621 namespace {
622   /// AST reader listener that dumps module information for a module
623   /// file.
624   class DumpModuleInfoListener : public ASTReaderListener {
625     llvm::raw_ostream &Out;
626 
627   public:
628     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
629 
630 #define DUMP_BOOLEAN(Value, Text)                       \
631     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
632 
633     bool ReadFullVersionInformation(StringRef FullVersion) override {
634       Out.indent(2)
635         << "Generated by "
636         << (FullVersion == getClangFullRepositoryVersion()? "this"
637                                                           : "a different")
638         << " Clang: " << FullVersion << "\n";
639       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
640     }
641 
642     void ReadModuleName(StringRef ModuleName) override {
643       Out.indent(2) << "Module name: " << ModuleName << "\n";
644     }
645     void ReadModuleMapFile(StringRef ModuleMapPath) override {
646       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
647     }
648 
649     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
650                              bool AllowCompatibleDifferences) override {
651       Out.indent(2) << "Language options:\n";
652 #define LANGOPT(Name, Bits, Default, Description) \
653       DUMP_BOOLEAN(LangOpts.Name, Description);
654 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
655       Out.indent(4) << Description << ": "                   \
656                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
657 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
658       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
659 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
660 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
661 #include "clang/Basic/LangOptions.def"
662 
663       if (!LangOpts.ModuleFeatures.empty()) {
664         Out.indent(4) << "Module features:\n";
665         for (StringRef Feature : LangOpts.ModuleFeatures)
666           Out.indent(6) << Feature << "\n";
667       }
668 
669       return false;
670     }
671 
672     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
673                            bool AllowCompatibleDifferences) override {
674       Out.indent(2) << "Target options:\n";
675       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
676       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
677       Out.indent(4) << "  TuneCPU: " << TargetOpts.TuneCPU << "\n";
678       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
679 
680       if (!TargetOpts.FeaturesAsWritten.empty()) {
681         Out.indent(4) << "Target features:\n";
682         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
683              I != N; ++I) {
684           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
685         }
686       }
687 
688       return false;
689     }
690 
691     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
692                                bool Complain) override {
693       Out.indent(2) << "Diagnostic options:\n";
694 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
695 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
696       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
697 #define VALUE_DIAGOPT(Name, Bits, Default) \
698       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
699 #include "clang/Basic/DiagnosticOptions.def"
700 
701       Out.indent(4) << "Diagnostic flags:\n";
702       for (const std::string &Warning : DiagOpts->Warnings)
703         Out.indent(6) << "-W" << Warning << "\n";
704       for (const std::string &Remark : DiagOpts->Remarks)
705         Out.indent(6) << "-R" << Remark << "\n";
706 
707       return false;
708     }
709 
710     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
711                                  StringRef SpecificModuleCachePath,
712                                  bool Complain) override {
713       Out.indent(2) << "Header search options:\n";
714       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
715       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
716       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
717       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
718                    "Use builtin include directories [-nobuiltininc]");
719       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
720                    "Use standard system include directories [-nostdinc]");
721       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
722                    "Use standard C++ include directories [-nostdinc++]");
723       DUMP_BOOLEAN(HSOpts.UseLibcxx,
724                    "Use libc++ (rather than libstdc++) [-stdlib=]");
725       return false;
726     }
727 
728     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
729                                  bool Complain,
730                                  std::string &SuggestedPredefines) override {
731       Out.indent(2) << "Preprocessor options:\n";
732       DUMP_BOOLEAN(PPOpts.UsePredefines,
733                    "Uses compiler/target-specific predefines [-undef]");
734       DUMP_BOOLEAN(PPOpts.DetailedRecord,
735                    "Uses detailed preprocessing record (for indexing)");
736 
737       if (!PPOpts.Macros.empty()) {
738         Out.indent(4) << "Predefined macros:\n";
739       }
740 
741       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
742              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
743            I != IEnd; ++I) {
744         Out.indent(6);
745         if (I->second)
746           Out << "-U";
747         else
748           Out << "-D";
749         Out << I->first << "\n";
750       }
751       return false;
752     }
753 
754     /// Indicates that a particular module file extension has been read.
755     void readModuleFileExtension(
756            const ModuleFileExtensionMetadata &Metadata) override {
757       Out.indent(2) << "Module file extension '"
758                     << Metadata.BlockName << "' " << Metadata.MajorVersion
759                     << "." << Metadata.MinorVersion;
760       if (!Metadata.UserInfo.empty()) {
761         Out << ": ";
762         Out.write_escaped(Metadata.UserInfo);
763       }
764 
765       Out << "\n";
766     }
767 
768     /// Tells the \c ASTReaderListener that we want to receive the
769     /// input files of the AST file via \c visitInputFile.
770     bool needsInputFileVisitation() override { return true; }
771 
772     /// Tells the \c ASTReaderListener that we want to receive the
773     /// input files of the AST file via \c visitInputFile.
774     bool needsSystemInputFileVisitation() override { return true; }
775 
776     /// Indicates that the AST file contains particular input file.
777     ///
778     /// \returns true to continue receiving the next input file, false to stop.
779     bool visitInputFile(StringRef Filename, bool isSystem,
780                         bool isOverridden, bool isExplicitModule) override {
781 
782       Out.indent(2) << "Input file: " << Filename;
783 
784       if (isSystem || isOverridden || isExplicitModule) {
785         Out << " [";
786         if (isSystem) {
787           Out << "System";
788           if (isOverridden || isExplicitModule)
789             Out << ", ";
790         }
791         if (isOverridden) {
792           Out << "Overridden";
793           if (isExplicitModule)
794             Out << ", ";
795         }
796         if (isExplicitModule)
797           Out << "ExplicitModule";
798 
799         Out << "]";
800       }
801 
802       Out << "\n";
803 
804       return true;
805     }
806 
807     /// Returns true if this \c ASTReaderListener wants to receive the
808     /// imports of the AST file via \c visitImport, false otherwise.
809     bool needsImportVisitation() const override { return true; }
810 
811     /// If needsImportVisitation returns \c true, this is called for each
812     /// AST file imported by this AST file.
813     void visitImport(StringRef ModuleName, StringRef Filename) override {
814       Out.indent(2) << "Imports module '" << ModuleName
815                     << "': " << Filename.str() << "\n";
816     }
817 #undef DUMP_BOOLEAN
818   };
819 }
820 
821 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
822   // The Object file reader also supports raw ast files and there is no point in
823   // being strict about the module file format in -module-file-info mode.
824   CI.getHeaderSearchOpts().ModuleFormat = "obj";
825   return true;
826 }
827 
828 static StringRef ModuleKindName(Module::ModuleKind MK) {
829   switch (MK) {
830   case Module::ModuleMapModule:
831     return "Module Map Module";
832   case Module::ModuleInterfaceUnit:
833     return "Interface Unit";
834   case Module::ModulePartitionInterface:
835     return "Partition Interface";
836   case Module::ModulePartitionImplementation:
837     return "Partition Implementation";
838   case Module::ModuleHeaderUnit:
839     return "Header Unit";
840   case Module::GlobalModuleFragment:
841     return "Global Module Fragment";
842   case Module::PrivateModuleFragment:
843     return "Private Module Fragment";
844   }
845   llvm_unreachable("unknown module kind!");
846 }
847 
848 void DumpModuleInfoAction::ExecuteAction() {
849   assert(isCurrentFileAST() && "dumping non-AST?");
850   // Set up the output file.
851   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
852   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
853   if (!OutputFileName.empty() && OutputFileName != "-") {
854     std::error_code EC;
855     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
856                                            llvm::sys::fs::OF_TextWithCRLF));
857     OutputStream = OutFile.get();
858   }
859   llvm::raw_ostream &Out = OutputStream ? *OutputStream : llvm::outs();
860 
861   Out << "Information for module file '" << getCurrentFile() << "':\n";
862   auto &FileMgr = getCompilerInstance().getFileManager();
863   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
864   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
865   bool IsRaw = (Magic.size() >= 4 && Magic[0] == 'C' && Magic[1] == 'P' &&
866                 Magic[2] == 'C' && Magic[3] == 'H');
867   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
868 
869   Preprocessor &PP = getCompilerInstance().getPreprocessor();
870   DumpModuleInfoListener Listener(Out);
871   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
872 
873   // The FrontendAction::BeginSourceFile () method loads the AST so that much
874   // of the information is already available and modules should have been
875   // loaded.
876 
877   const LangOptions &LO = getCurrentASTUnit().getLangOpts();
878   if (LO.CPlusPlusModules && !LO.CurrentModule.empty()) {
879 
880     ASTReader *R = getCurrentASTUnit().getASTReader().get();
881     unsigned SubModuleCount = R->getTotalNumSubmodules();
882     serialization::ModuleFile &MF = R->getModuleManager().getPrimaryModule();
883     Out << "  ====== C++20 Module structure ======\n";
884 
885     if (MF.ModuleName != LO.CurrentModule)
886       Out << "  Mismatched module names : " << MF.ModuleName << " and "
887           << LO.CurrentModule << "\n";
888 
889     struct SubModInfo {
890       unsigned Idx;
891       Module *Mod;
892       Module::ModuleKind Kind;
893       std::string &Name;
894       bool Seen;
895     };
896     std::map<std::string, SubModInfo> SubModMap;
897     auto PrintSubMapEntry = [&](std::string Name, Module::ModuleKind Kind) {
898       Out << "    " << ModuleKindName(Kind) << " '" << Name << "'";
899       auto I = SubModMap.find(Name);
900       if (I == SubModMap.end())
901         Out << " was not found in the sub modules!\n";
902       else {
903         I->second.Seen = true;
904         Out << " is at index #" << I->second.Idx << "\n";
905       }
906     };
907     Module *Primary = nullptr;
908     for (unsigned Idx = 0; Idx <= SubModuleCount; ++Idx) {
909       Module *M = R->getModule(Idx);
910       if (!M)
911         continue;
912       if (M->Name == LO.CurrentModule) {
913         Primary = M;
914         Out << "  " << ModuleKindName(M->Kind) << " '" << LO.CurrentModule
915             << "' is the Primary Module at index #" << Idx << "\n";
916         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, true}});
917       } else
918         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, false}});
919     }
920     if (Primary) {
921       if (!Primary->submodules().empty())
922         Out << "   Sub Modules:\n";
923       for (auto MI : Primary->submodules()) {
924         PrintSubMapEntry(MI->Name, MI->Kind);
925       }
926       if (!Primary->Imports.empty())
927         Out << "   Imports:\n";
928       for (auto IMP : Primary->Imports) {
929         PrintSubMapEntry(IMP->Name, IMP->Kind);
930       }
931       if (!Primary->Exports.empty())
932         Out << "   Exports:\n";
933       for (unsigned MN = 0, N = Primary->Exports.size(); MN != N; ++MN) {
934         if (Module *M = Primary->Exports[MN].getPointer()) {
935           PrintSubMapEntry(M->Name, M->Kind);
936         }
937       }
938     }
939     // Now let's print out any modules we did not see as part of the Primary.
940     for (auto SM : SubModMap) {
941       if (!SM.second.Seen && SM.second.Mod) {
942         Out << "  " << ModuleKindName(SM.second.Kind) << " '" << SM.first
943             << "' at index #" << SM.second.Idx
944             << " has no direct reference in the Primary\n";
945       }
946     }
947     Out << "  ====== ======\n";
948   }
949 
950   // The reminder of the output is produced from the listener as the AST
951   // FileCcontrolBlock is (re-)parsed.
952   ASTReader::readASTFileControlBlock(
953       getCurrentFile(), FileMgr, getCompilerInstance().getPCHContainerReader(),
954       /*FindModuleFileExtensions=*/true, Listener,
955       HSOpts.ModulesValidateDiagnosticOptions);
956 }
957 
958 //===----------------------------------------------------------------------===//
959 // Preprocessor Actions
960 //===----------------------------------------------------------------------===//
961 
962 void DumpRawTokensAction::ExecuteAction() {
963   Preprocessor &PP = getCompilerInstance().getPreprocessor();
964   SourceManager &SM = PP.getSourceManager();
965 
966   // Start lexing the specified input file.
967   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
968   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
969   RawLex.SetKeepWhitespaceMode(true);
970 
971   Token RawTok;
972   RawLex.LexFromRawLexer(RawTok);
973   while (RawTok.isNot(tok::eof)) {
974     PP.DumpToken(RawTok, true);
975     llvm::errs() << "\n";
976     RawLex.LexFromRawLexer(RawTok);
977   }
978 }
979 
980 void DumpTokensAction::ExecuteAction() {
981   Preprocessor &PP = getCompilerInstance().getPreprocessor();
982   // Start preprocessing the specified input file.
983   Token Tok;
984   PP.EnterMainSourceFile();
985   do {
986     PP.Lex(Tok);
987     PP.DumpToken(Tok, true);
988     llvm::errs() << "\n";
989   } while (Tok.isNot(tok::eof));
990 }
991 
992 void PreprocessOnlyAction::ExecuteAction() {
993   Preprocessor &PP = getCompilerInstance().getPreprocessor();
994 
995   // Ignore unknown pragmas.
996   PP.IgnorePragmas();
997 
998   Token Tok;
999   // Start parsing the specified input file.
1000   PP.EnterMainSourceFile();
1001   do {
1002     PP.Lex(Tok);
1003   } while (Tok.isNot(tok::eof));
1004 }
1005 
1006 void PrintPreprocessedAction::ExecuteAction() {
1007   CompilerInstance &CI = getCompilerInstance();
1008   // Output file may need to be set to 'Binary', to avoid converting Unix style
1009   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>) on Windows.
1010   //
1011   // Look to see what type of line endings the file uses. If there's a
1012   // CRLF, then we won't open the file up in binary mode. If there is
1013   // just an LF or CR, then we will open the file up in binary mode.
1014   // In this fashion, the output format should match the input format, unless
1015   // the input format has inconsistent line endings.
1016   //
1017   // This should be a relatively fast operation since most files won't have
1018   // all of their source code on a single line. However, that is still a
1019   // concern, so if we scan for too long, we'll just assume the file should
1020   // be opened in binary mode.
1021 
1022   bool BinaryMode = false;
1023   if (llvm::Triple(LLVM_HOST_TRIPLE).isOSWindows()) {
1024     BinaryMode = true;
1025     const SourceManager &SM = CI.getSourceManager();
1026     if (llvm::Optional<llvm::MemoryBufferRef> Buffer =
1027             SM.getBufferOrNone(SM.getMainFileID())) {
1028       const char *cur = Buffer->getBufferStart();
1029       const char *end = Buffer->getBufferEnd();
1030       const char *next = (cur != end) ? cur + 1 : end;
1031 
1032       // Limit ourselves to only scanning 256 characters into the source
1033       // file.  This is mostly a check in case the file has no
1034       // newlines whatsoever.
1035       if (end - cur > 256)
1036         end = cur + 256;
1037 
1038       while (next < end) {
1039         if (*cur == 0x0D) {  // CR
1040           if (*next == 0x0A) // CRLF
1041             BinaryMode = false;
1042 
1043           break;
1044         } else if (*cur == 0x0A) // LF
1045           break;
1046 
1047         ++cur;
1048         ++next;
1049       }
1050     }
1051   }
1052 
1053   std::unique_ptr<raw_ostream> OS =
1054       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
1055   if (!OS) return;
1056 
1057   // If we're preprocessing a module map, start by dumping the contents of the
1058   // module itself before switching to the input buffer.
1059   auto &Input = getCurrentInput();
1060   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
1061     if (Input.isFile()) {
1062       (*OS) << "# 1 \"";
1063       OS->write_escaped(Input.getFile());
1064       (*OS) << "\"\n";
1065     }
1066     getCurrentModule()->print(*OS);
1067     (*OS) << "#pragma clang module contents\n";
1068   }
1069 
1070   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
1071                            CI.getPreprocessorOutputOpts());
1072 }
1073 
1074 void PrintPreambleAction::ExecuteAction() {
1075   switch (getCurrentFileKind().getLanguage()) {
1076   case Language::C:
1077   case Language::CXX:
1078   case Language::ObjC:
1079   case Language::ObjCXX:
1080   case Language::OpenCL:
1081   case Language::OpenCLCXX:
1082   case Language::CUDA:
1083   case Language::HIP:
1084   case Language::HLSL:
1085     break;
1086 
1087   case Language::Unknown:
1088   case Language::Asm:
1089   case Language::LLVM_IR:
1090   case Language::RenderScript:
1091     // We can't do anything with these.
1092     return;
1093   }
1094 
1095   // We don't expect to find any #include directives in a preprocessed input.
1096   if (getCurrentFileKind().isPreprocessed())
1097     return;
1098 
1099   CompilerInstance &CI = getCompilerInstance();
1100   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
1101   if (Buffer) {
1102     unsigned Preamble =
1103         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
1104     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
1105   }
1106 }
1107 
1108 void DumpCompilerOptionsAction::ExecuteAction() {
1109   CompilerInstance &CI = getCompilerInstance();
1110   std::unique_ptr<raw_ostream> OSP =
1111       CI.createDefaultOutputFile(false, getCurrentFile());
1112   if (!OSP)
1113     return;
1114 
1115   raw_ostream &OS = *OSP;
1116   const Preprocessor &PP = CI.getPreprocessor();
1117   const LangOptions &LangOpts = PP.getLangOpts();
1118 
1119   // FIXME: Rather than manually format the JSON (which is awkward due to
1120   // needing to remove trailing commas), this should make use of a JSON library.
1121   // FIXME: Instead of printing enums as an integral value and specifying the
1122   // type as a separate field, use introspection to print the enumerator.
1123 
1124   OS << "{\n";
1125   OS << "\n\"features\" : [\n";
1126   {
1127     llvm::SmallString<128> Str;
1128 #define FEATURE(Name, Predicate)                                               \
1129   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1130       .toVector(Str);
1131 #include "clang/Basic/Features.def"
1132 #undef FEATURE
1133     // Remove the newline and comma from the last entry to ensure this remains
1134     // valid JSON.
1135     OS << Str.substr(0, Str.size() - 2);
1136   }
1137   OS << "\n],\n";
1138 
1139   OS << "\n\"extensions\" : [\n";
1140   {
1141     llvm::SmallString<128> Str;
1142 #define EXTENSION(Name, Predicate)                                             \
1143   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1144       .toVector(Str);
1145 #include "clang/Basic/Features.def"
1146 #undef EXTENSION
1147     // Remove the newline and comma from the last entry to ensure this remains
1148     // valid JSON.
1149     OS << Str.substr(0, Str.size() - 2);
1150   }
1151   OS << "\n]\n";
1152 
1153   OS << "}";
1154 }
1155 
1156 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
1157   CompilerInstance &CI = getCompilerInstance();
1158   SourceManager &SM = CI.getPreprocessor().getSourceManager();
1159   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
1160 
1161   llvm::SmallVector<dependency_directives_scan::Token, 16> Tokens;
1162   llvm::SmallVector<dependency_directives_scan::Directive, 32> Directives;
1163   if (scanSourceForDependencyDirectives(
1164           FromFile.getBuffer(), Tokens, Directives, &CI.getDiagnostics(),
1165           SM.getLocForStartOfFile(SM.getMainFileID()))) {
1166     assert(CI.getDiagnostics().hasErrorOccurred() &&
1167            "no errors reported for failure");
1168 
1169     // Preprocess the source when verifying the diagnostics to capture the
1170     // 'expected' comments.
1171     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
1172       // Make sure we don't emit new diagnostics!
1173       CI.getDiagnostics().setSuppressAllDiagnostics(true);
1174       Preprocessor &PP = getCompilerInstance().getPreprocessor();
1175       PP.EnterMainSourceFile();
1176       Token Tok;
1177       do {
1178         PP.Lex(Tok);
1179       } while (Tok.isNot(tok::eof));
1180     }
1181     return;
1182   }
1183   printDependencyDirectivesAsSource(FromFile.getBuffer(), Directives,
1184                                     llvm::outs());
1185 }
1186 
1187 void GetDependenciesByModuleNameAction::ExecuteAction() {
1188   CompilerInstance &CI = getCompilerInstance();
1189   Preprocessor &PP = CI.getPreprocessor();
1190   SourceManager &SM = PP.getSourceManager();
1191   FileID MainFileID = SM.getMainFileID();
1192   SourceLocation FileStart = SM.getLocForStartOfFile(MainFileID);
1193   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1194   IdentifierInfo *ModuleID = PP.getIdentifierInfo(ModuleName);
1195   Path.push_back(std::make_pair(ModuleID, FileStart));
1196   auto ModResult = CI.loadModule(FileStart, Path, Module::Hidden, false);
1197   PPCallbacks *CB = PP.getPPCallbacks();
1198   CB->moduleImport(SourceLocation(), Path, ModResult);
1199 }
1200