xref: /llvm-project/clang/lib/Frontend/FrontendActions.cpp (revision ec527b21bb4196355184aa95ef31aa561b8e8b7b) 
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 <optional>
37 #include <system_error>
38 
39 using namespace clang;
40 
41 namespace {
42 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
43   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
44                                         : nullptr;
45 }
46 
47 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
48   if (Action.hasCodeCompletionSupport() &&
49       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
50     CI.createCodeCompletionConsumer();
51 
52   if (!CI.hasSema())
53     CI.createSema(Action.getTranslationUnitKind(),
54                   GetCodeCompletionConsumer(CI));
55 }
56 } // namespace
57 
58 //===----------------------------------------------------------------------===//
59 // Custom Actions
60 //===----------------------------------------------------------------------===//
61 
62 std::unique_ptr<ASTConsumer>
63 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
64   return std::make_unique<ASTConsumer>();
65 }
66 
67 void InitOnlyAction::ExecuteAction() {
68 }
69 
70 // Basically PreprocessOnlyAction::ExecuteAction.
71 void ReadPCHAndPreprocessAction::ExecuteAction() {
72   Preprocessor &PP = getCompilerInstance().getPreprocessor();
73 
74   // Ignore unknown pragmas.
75   PP.IgnorePragmas();
76 
77   Token Tok;
78   // Start parsing the specified input file.
79   PP.EnterMainSourceFile();
80   do {
81     PP.Lex(Tok);
82   } while (Tok.isNot(tok::eof));
83 }
84 
85 std::unique_ptr<ASTConsumer>
86 ReadPCHAndPreprocessAction::CreateASTConsumer(CompilerInstance &CI,
87                                               StringRef InFile) {
88   return std::make_unique<ASTConsumer>();
89 }
90 
91 //===----------------------------------------------------------------------===//
92 // AST Consumer Actions
93 //===----------------------------------------------------------------------===//
94 
95 std::unique_ptr<ASTConsumer>
96 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
97   if (std::unique_ptr<raw_ostream> OS =
98           CI.createDefaultOutputFile(false, InFile))
99     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
100   return nullptr;
101 }
102 
103 std::unique_ptr<ASTConsumer>
104 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
105   const FrontendOptions &Opts = CI.getFrontendOpts();
106   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
107                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
108                          Opts.ASTDumpLookups, Opts.ASTDumpDeclTypes,
109                          Opts.ASTDumpFormat);
110 }
111 
112 std::unique_ptr<ASTConsumer>
113 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
114   return CreateASTDeclNodeLister();
115 }
116 
117 std::unique_ptr<ASTConsumer>
118 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
119   return CreateASTViewer();
120 }
121 
122 std::unique_ptr<ASTConsumer>
123 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
124   std::string Sysroot;
125   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
126     return nullptr;
127 
128   std::string OutputFile;
129   std::unique_ptr<raw_pwrite_stream> OS =
130       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
131   if (!OS)
132     return nullptr;
133 
134   if (!CI.getFrontendOpts().RelocatablePCH)
135     Sysroot.clear();
136 
137   const auto &FrontendOpts = CI.getFrontendOpts();
138   auto Buffer = std::make_shared<PCHBuffer>();
139   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
140   Consumers.push_back(std::make_unique<PCHGenerator>(
141       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
142       FrontendOpts.ModuleFileExtensions,
143       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
144       FrontendOpts.IncludeTimestamps, FrontendOpts.BuildingImplicitModule,
145       +CI.getLangOpts().CacheGeneratedPCH));
146   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
147       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
148 
149   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
150 }
151 
152 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
153                                                     std::string &Sysroot) {
154   Sysroot = CI.getHeaderSearchOpts().Sysroot;
155   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
156     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
157     return false;
158   }
159 
160   return true;
161 }
162 
163 std::unique_ptr<llvm::raw_pwrite_stream>
164 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
165                                     std::string &OutputFile) {
166   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
167   std::unique_ptr<raw_pwrite_stream> OS = CI.createDefaultOutputFile(
168       /*Binary=*/true, InFile, /*Extension=*/"", /*RemoveFileOnSignal=*/false);
169   if (!OS)
170     return nullptr;
171 
172   OutputFile = CI.getFrontendOpts().OutputFile;
173   return OS;
174 }
175 
176 bool GeneratePCHAction::shouldEraseOutputFiles() {
177   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
178     return false;
179   return ASTFrontendAction::shouldEraseOutputFiles();
180 }
181 
182 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
183   CI.getLangOpts().CompilingPCH = true;
184   return true;
185 }
186 
187 std::vector<std::unique_ptr<ASTConsumer>>
188 GenerateModuleAction::CreateMultiplexConsumer(CompilerInstance &CI,
189                                               StringRef InFile) {
190   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
191   if (!OS)
192     return {};
193 
194   std::string OutputFile = CI.getFrontendOpts().OutputFile;
195   std::string Sysroot;
196 
197   auto Buffer = std::make_shared<PCHBuffer>();
198   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
199 
200   Consumers.push_back(std::make_unique<PCHGenerator>(
201       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
202       CI.getFrontendOpts().ModuleFileExtensions,
203       /*AllowASTWithErrors=*/
204       +CI.getFrontendOpts().AllowPCMWithCompilerErrors,
205       /*IncludeTimestamps=*/
206       +CI.getFrontendOpts().BuildingImplicitModule &&
207           +CI.getFrontendOpts().IncludeTimestamps,
208       /*BuildingImplicitModule=*/+CI.getFrontendOpts().BuildingImplicitModule,
209       /*ShouldCacheASTInMemory=*/
210       +CI.getFrontendOpts().BuildingImplicitModule));
211   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
212       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
213   return Consumers;
214 }
215 
216 std::unique_ptr<ASTConsumer>
217 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
218                                         StringRef InFile) {
219   std::vector<std::unique_ptr<ASTConsumer>> Consumers =
220       CreateMultiplexConsumer(CI, InFile);
221   if (Consumers.empty())
222     return nullptr;
223 
224   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
225 }
226 
227 bool GenerateModuleAction::shouldEraseOutputFiles() {
228   return !getCompilerInstance().getFrontendOpts().AllowPCMWithCompilerErrors &&
229          ASTFrontendAction::shouldEraseOutputFiles();
230 }
231 
232 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
233     CompilerInstance &CI) {
234   if (!CI.getLangOpts().Modules) {
235     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
236     return false;
237   }
238 
239   return GenerateModuleAction::BeginSourceFileAction(CI);
240 }
241 
242 std::unique_ptr<raw_pwrite_stream>
243 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
244                                                     StringRef InFile) {
245   // If no output file was provided, figure out where this module would go
246   // in the module cache.
247   if (CI.getFrontendOpts().OutputFile.empty()) {
248     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
249     if (ModuleMapFile.empty())
250       ModuleMapFile = InFile;
251 
252     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
253     CI.getFrontendOpts().OutputFile =
254         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
255                                    ModuleMapFile);
256   }
257 
258   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
259   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, /*Extension=*/"",
260                                     /*RemoveFileOnSignal=*/false,
261                                     /*CreateMissingDirectories=*/true,
262                                     /*ForceUseTemporary=*/true);
263 }
264 
265 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
266     CompilerInstance &CI) {
267   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
268 
269   return GenerateModuleAction::BeginSourceFileAction(CI);
270 }
271 
272 std::unique_ptr<ASTConsumer>
273 GenerateModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
274                                                  StringRef InFile) {
275   CI.getHeaderSearchOpts().ModulesSkipDiagnosticOptions = true;
276   CI.getHeaderSearchOpts().ModulesSkipHeaderSearchPaths = true;
277 
278   std::vector<std::unique_ptr<ASTConsumer>> Consumers =
279       CreateMultiplexConsumer(CI, InFile);
280   if (Consumers.empty())
281     return nullptr;
282 
283   if (CI.getFrontendOpts().GenReducedBMI &&
284       !CI.getFrontendOpts().ModuleOutputPath.empty()) {
285     Consumers.push_back(std::make_unique<ReducedBMIGenerator>(
286         CI.getPreprocessor(), CI.getModuleCache(),
287         CI.getFrontendOpts().ModuleOutputPath));
288   }
289 
290   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
291 }
292 
293 std::unique_ptr<raw_pwrite_stream>
294 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
295                                                 StringRef InFile) {
296   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
297 }
298 
299 std::unique_ptr<ASTConsumer>
300 GenerateReducedModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
301                                                         StringRef InFile) {
302   return std::make_unique<ReducedBMIGenerator>(CI.getPreprocessor(),
303                                                CI.getModuleCache(),
304                                                CI.getFrontendOpts().OutputFile);
305 }
306 
307 bool GenerateHeaderUnitAction::BeginSourceFileAction(CompilerInstance &CI) {
308   if (!CI.getLangOpts().CPlusPlusModules) {
309     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
310     return false;
311   }
312   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderUnit);
313   return GenerateModuleAction::BeginSourceFileAction(CI);
314 }
315 
316 std::unique_ptr<raw_pwrite_stream>
317 GenerateHeaderUnitAction::CreateOutputFile(CompilerInstance &CI,
318                                            StringRef InFile) {
319   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
320 }
321 
322 SyntaxOnlyAction::~SyntaxOnlyAction() {
323 }
324 
325 std::unique_ptr<ASTConsumer>
326 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
327   return std::make_unique<ASTConsumer>();
328 }
329 
330 std::unique_ptr<ASTConsumer>
331 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
332                                         StringRef InFile) {
333   return std::make_unique<ASTConsumer>();
334 }
335 
336 std::unique_ptr<ASTConsumer>
337 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
338   return std::make_unique<ASTConsumer>();
339 }
340 
341 void VerifyPCHAction::ExecuteAction() {
342   CompilerInstance &CI = getCompilerInstance();
343   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
344   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
345   std::unique_ptr<ASTReader> Reader(new ASTReader(
346       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
347       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
348       Sysroot.empty() ? "" : Sysroot.c_str(),
349       DisableValidationForModuleKind::None,
350       /*AllowASTWithCompilerErrors*/ false,
351       /*AllowConfigurationMismatch*/ true,
352       /*ValidateSystemInputs*/ true));
353 
354   Reader->ReadAST(getCurrentFile(),
355                   Preamble ? serialization::MK_Preamble
356                            : serialization::MK_PCH,
357                   SourceLocation(),
358                   ASTReader::ARR_ConfigurationMismatch);
359 }
360 
361 namespace {
362 struct TemplightEntry {
363   std::string Name;
364   std::string Kind;
365   std::string Event;
366   std::string DefinitionLocation;
367   std::string PointOfInstantiation;
368 };
369 } // namespace
370 
371 namespace llvm {
372 namespace yaml {
373 template <> struct MappingTraits<TemplightEntry> {
374   static void mapping(IO &io, TemplightEntry &fields) {
375     io.mapRequired("name", fields.Name);
376     io.mapRequired("kind", fields.Kind);
377     io.mapRequired("event", fields.Event);
378     io.mapRequired("orig", fields.DefinitionLocation);
379     io.mapRequired("poi", fields.PointOfInstantiation);
380   }
381 };
382 } // namespace yaml
383 } // namespace llvm
384 
385 namespace {
386 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
387   using CodeSynthesisContext = Sema::CodeSynthesisContext;
388 
389 public:
390   void initialize(const Sema &) override {}
391 
392   void finalize(const Sema &) override {}
393 
394   void atTemplateBegin(const Sema &TheSema,
395                        const CodeSynthesisContext &Inst) override {
396     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
397   }
398 
399   void atTemplateEnd(const Sema &TheSema,
400                      const CodeSynthesisContext &Inst) override {
401     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
402   }
403 
404 private:
405   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
406     switch (Kind) {
407     case CodeSynthesisContext::TemplateInstantiation:
408       return "TemplateInstantiation";
409     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
410       return "DefaultTemplateArgumentInstantiation";
411     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
412       return "DefaultFunctionArgumentInstantiation";
413     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
414       return "ExplicitTemplateArgumentSubstitution";
415     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
416       return "DeducedTemplateArgumentSubstitution";
417     case CodeSynthesisContext::LambdaExpressionSubstitution:
418       return "LambdaExpressionSubstitution";
419     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
420       return "PriorTemplateArgumentSubstitution";
421     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
422       return "DefaultTemplateArgumentChecking";
423     case CodeSynthesisContext::ExceptionSpecEvaluation:
424       return "ExceptionSpecEvaluation";
425     case CodeSynthesisContext::ExceptionSpecInstantiation:
426       return "ExceptionSpecInstantiation";
427     case CodeSynthesisContext::DeclaringSpecialMember:
428       return "DeclaringSpecialMember";
429     case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
430       return "DeclaringImplicitEqualityComparison";
431     case CodeSynthesisContext::DefiningSynthesizedFunction:
432       return "DefiningSynthesizedFunction";
433     case CodeSynthesisContext::RewritingOperatorAsSpaceship:
434       return "RewritingOperatorAsSpaceship";
435     case CodeSynthesisContext::Memoization:
436       return "Memoization";
437     case CodeSynthesisContext::ConstraintsCheck:
438       return "ConstraintsCheck";
439     case CodeSynthesisContext::ConstraintSubstitution:
440       return "ConstraintSubstitution";
441     case CodeSynthesisContext::ConstraintNormalization:
442       return "ConstraintNormalization";
443     case CodeSynthesisContext::RequirementParameterInstantiation:
444       return "RequirementParameterInstantiation";
445     case CodeSynthesisContext::ParameterMappingSubstitution:
446       return "ParameterMappingSubstitution";
447     case CodeSynthesisContext::RequirementInstantiation:
448       return "RequirementInstantiation";
449     case CodeSynthesisContext::NestedRequirementConstraintsCheck:
450       return "NestedRequirementConstraintsCheck";
451     case CodeSynthesisContext::InitializingStructuredBinding:
452       return "InitializingStructuredBinding";
453     case CodeSynthesisContext::MarkingClassDllexported:
454       return "MarkingClassDllexported";
455     case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
456       return "BuildingBuiltinDumpStructCall";
457     case CodeSynthesisContext::BuildingDeductionGuides:
458       return "BuildingDeductionGuides";
459     case CodeSynthesisContext::TypeAliasTemplateInstantiation:
460       return "TypeAliasTemplateInstantiation";
461     }
462     return "";
463   }
464 
465   template <bool BeginInstantiation>
466   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
467                                     const CodeSynthesisContext &Inst) {
468     std::string YAML;
469     {
470       llvm::raw_string_ostream OS(YAML);
471       llvm::yaml::Output YO(OS);
472       TemplightEntry Entry =
473           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
474       llvm::yaml::EmptyContext Context;
475       llvm::yaml::yamlize(YO, Entry, true, Context);
476     }
477     Out << "---" << YAML << "\n";
478   }
479 
480   static void printEntryName(const Sema &TheSema, const Decl *Entity,
481                              llvm::raw_string_ostream &OS) {
482     auto *NamedTemplate = cast<NamedDecl>(Entity);
483 
484     PrintingPolicy Policy = TheSema.Context.getPrintingPolicy();
485     // FIXME: Also ask for FullyQualifiedNames?
486     Policy.SuppressDefaultTemplateArgs = false;
487     NamedTemplate->getNameForDiagnostic(OS, Policy, true);
488 
489     if (!OS.str().empty())
490       return;
491 
492     Decl *Ctx = Decl::castFromDeclContext(NamedTemplate->getDeclContext());
493     NamedDecl *NamedCtx = dyn_cast_or_null<NamedDecl>(Ctx);
494 
495     if (const auto *Decl = dyn_cast<TagDecl>(NamedTemplate)) {
496       if (const auto *R = dyn_cast<RecordDecl>(Decl)) {
497         if (R->isLambda()) {
498           OS << "lambda at ";
499           Decl->getLocation().print(OS, TheSema.getSourceManager());
500           return;
501         }
502       }
503       OS << "unnamed " << Decl->getKindName();
504       return;
505     }
506 
507     assert(NamedCtx && "NamedCtx cannot be null");
508 
509     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
510       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
511          << " ";
512       if (Decl->getFunctionScopeDepth() > 0)
513         OS << "(at depth " << Decl->getFunctionScopeDepth() << ") ";
514       OS << "of ";
515       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
516       return;
517     }
518 
519     if (const auto *Decl = dyn_cast<TemplateTypeParmDecl>(NamedTemplate)) {
520       if (const Type *Ty = Decl->getTypeForDecl()) {
521         if (const auto *TTPT = dyn_cast_or_null<TemplateTypeParmType>(Ty)) {
522           OS << "unnamed template type parameter " << TTPT->getIndex() << " ";
523           if (TTPT->getDepth() > 0)
524             OS << "(at depth " << TTPT->getDepth() << ") ";
525           OS << "of ";
526           NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
527           return;
528         }
529       }
530     }
531 
532     if (const auto *Decl = dyn_cast<NonTypeTemplateParmDecl>(NamedTemplate)) {
533       OS << "unnamed template non-type parameter " << Decl->getIndex() << " ";
534       if (Decl->getDepth() > 0)
535         OS << "(at depth " << Decl->getDepth() << ") ";
536       OS << "of ";
537       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
538       return;
539     }
540 
541     if (const auto *Decl = dyn_cast<TemplateTemplateParmDecl>(NamedTemplate)) {
542       OS << "unnamed template template parameter " << Decl->getIndex() << " ";
543       if (Decl->getDepth() > 0)
544         OS << "(at depth " << Decl->getDepth() << ") ";
545       OS << "of ";
546       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
547       return;
548     }
549 
550     llvm_unreachable("Failed to retrieve a name for this entry!");
551     OS << "unnamed identifier";
552   }
553 
554   template <bool BeginInstantiation>
555   static TemplightEntry getTemplightEntry(const Sema &TheSema,
556                                           const CodeSynthesisContext &Inst) {
557     TemplightEntry Entry;
558     Entry.Kind = toString(Inst.Kind);
559     Entry.Event = BeginInstantiation ? "Begin" : "End";
560     llvm::raw_string_ostream OS(Entry.Name);
561     printEntryName(TheSema, Inst.Entity, OS);
562     const PresumedLoc DefLoc =
563         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
564     if (!DefLoc.isInvalid())
565       Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
566                                  std::to_string(DefLoc.getLine()) + ":" +
567                                  std::to_string(DefLoc.getColumn());
568     const PresumedLoc PoiLoc =
569         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
570     if (!PoiLoc.isInvalid()) {
571       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
572                                    std::to_string(PoiLoc.getLine()) + ":" +
573                                    std::to_string(PoiLoc.getColumn());
574     }
575     return Entry;
576   }
577 };
578 } // namespace
579 
580 std::unique_ptr<ASTConsumer>
581 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
582   return std::make_unique<ASTConsumer>();
583 }
584 
585 void TemplightDumpAction::ExecuteAction() {
586   CompilerInstance &CI = getCompilerInstance();
587 
588   // This part is normally done by ASTFrontEndAction, but needs to happen
589   // before Templight observers can be created
590   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
591   // here so the source manager would be initialized.
592   EnsureSemaIsCreated(CI, *this);
593 
594   CI.getSema().TemplateInstCallbacks.push_back(
595       std::make_unique<DefaultTemplateInstCallback>());
596   ASTFrontendAction::ExecuteAction();
597 }
598 
599 namespace {
600   /// AST reader listener that dumps module information for a module
601   /// file.
602   class DumpModuleInfoListener : public ASTReaderListener {
603     llvm::raw_ostream &Out;
604 
605   public:
606     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
607 
608 #define DUMP_BOOLEAN(Value, Text)                       \
609     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
610 
611     bool ReadFullVersionInformation(StringRef FullVersion) override {
612       Out.indent(2)
613         << "Generated by "
614         << (FullVersion == getClangFullRepositoryVersion()? "this"
615                                                           : "a different")
616         << " Clang: " << FullVersion << "\n";
617       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
618     }
619 
620     void ReadModuleName(StringRef ModuleName) override {
621       Out.indent(2) << "Module name: " << ModuleName << "\n";
622     }
623     void ReadModuleMapFile(StringRef ModuleMapPath) override {
624       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
625     }
626 
627     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
628                              bool AllowCompatibleDifferences) override {
629       Out.indent(2) << "Language options:\n";
630 #define LANGOPT(Name, Bits, Default, Description) \
631       DUMP_BOOLEAN(LangOpts.Name, Description);
632 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
633       Out.indent(4) << Description << ": "                   \
634                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
635 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
636       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
637 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
638 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
639 #include "clang/Basic/LangOptions.def"
640 
641       if (!LangOpts.ModuleFeatures.empty()) {
642         Out.indent(4) << "Module features:\n";
643         for (StringRef Feature : LangOpts.ModuleFeatures)
644           Out.indent(6) << Feature << "\n";
645       }
646 
647       return false;
648     }
649 
650     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
651                            bool AllowCompatibleDifferences) override {
652       Out.indent(2) << "Target options:\n";
653       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
654       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
655       Out.indent(4) << "  TuneCPU: " << TargetOpts.TuneCPU << "\n";
656       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
657 
658       if (!TargetOpts.FeaturesAsWritten.empty()) {
659         Out.indent(4) << "Target features:\n";
660         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
661              I != N; ++I) {
662           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
663         }
664       }
665 
666       return false;
667     }
668 
669     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
670                                bool Complain) override {
671       Out.indent(2) << "Diagnostic options:\n";
672 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
673 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
674       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
675 #define VALUE_DIAGOPT(Name, Bits, Default) \
676       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
677 #include "clang/Basic/DiagnosticOptions.def"
678 
679       Out.indent(4) << "Diagnostic flags:\n";
680       for (const std::string &Warning : DiagOpts->Warnings)
681         Out.indent(6) << "-W" << Warning << "\n";
682       for (const std::string &Remark : DiagOpts->Remarks)
683         Out.indent(6) << "-R" << Remark << "\n";
684 
685       return false;
686     }
687 
688     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
689                                  StringRef SpecificModuleCachePath,
690                                  bool Complain) override {
691       Out.indent(2) << "Header search options:\n";
692       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
693       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
694       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
695       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
696                    "Use builtin include directories [-nobuiltininc]");
697       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
698                    "Use standard system include directories [-nostdinc]");
699       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
700                    "Use standard C++ include directories [-nostdinc++]");
701       DUMP_BOOLEAN(HSOpts.UseLibcxx,
702                    "Use libc++ (rather than libstdc++) [-stdlib=]");
703       return false;
704     }
705 
706     bool ReadHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
707                                bool Complain) override {
708       Out.indent(2) << "Header search paths:\n";
709       Out.indent(4) << "User entries:\n";
710       for (const auto &Entry : HSOpts.UserEntries)
711         Out.indent(6) << Entry.Path << "\n";
712       Out.indent(4) << "System header prefixes:\n";
713       for (const auto &Prefix : HSOpts.SystemHeaderPrefixes)
714         Out.indent(6) << Prefix.Prefix << "\n";
715       Out.indent(4) << "VFS overlay files:\n";
716       for (const auto &Overlay : HSOpts.VFSOverlayFiles)
717         Out.indent(6) << Overlay << "\n";
718       return false;
719     }
720 
721     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
722                                  bool ReadMacros, bool Complain,
723                                  std::string &SuggestedPredefines) override {
724       Out.indent(2) << "Preprocessor options:\n";
725       DUMP_BOOLEAN(PPOpts.UsePredefines,
726                    "Uses compiler/target-specific predefines [-undef]");
727       DUMP_BOOLEAN(PPOpts.DetailedRecord,
728                    "Uses detailed preprocessing record (for indexing)");
729 
730       if (ReadMacros) {
731         Out.indent(4) << "Predefined macros:\n";
732       }
733 
734       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
735              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
736            I != IEnd; ++I) {
737         Out.indent(6);
738         if (I->second)
739           Out << "-U";
740         else
741           Out << "-D";
742         Out << I->first << "\n";
743       }
744       return false;
745     }
746 
747     /// Indicates that a particular module file extension has been read.
748     void readModuleFileExtension(
749            const ModuleFileExtensionMetadata &Metadata) override {
750       Out.indent(2) << "Module file extension '"
751                     << Metadata.BlockName << "' " << Metadata.MajorVersion
752                     << "." << Metadata.MinorVersion;
753       if (!Metadata.UserInfo.empty()) {
754         Out << ": ";
755         Out.write_escaped(Metadata.UserInfo);
756       }
757 
758       Out << "\n";
759     }
760 
761     /// Tells the \c ASTReaderListener that we want to receive the
762     /// input files of the AST file via \c visitInputFile.
763     bool needsInputFileVisitation() override { return true; }
764 
765     /// Tells the \c ASTReaderListener that we want to receive the
766     /// input files of the AST file via \c visitInputFile.
767     bool needsSystemInputFileVisitation() override { return true; }
768 
769     /// Indicates that the AST file contains particular input file.
770     ///
771     /// \returns true to continue receiving the next input file, false to stop.
772     bool visitInputFile(StringRef Filename, bool isSystem,
773                         bool isOverridden, bool isExplicitModule) override {
774 
775       Out.indent(2) << "Input file: " << Filename;
776 
777       if (isSystem || isOverridden || isExplicitModule) {
778         Out << " [";
779         if (isSystem) {
780           Out << "System";
781           if (isOverridden || isExplicitModule)
782             Out << ", ";
783         }
784         if (isOverridden) {
785           Out << "Overridden";
786           if (isExplicitModule)
787             Out << ", ";
788         }
789         if (isExplicitModule)
790           Out << "ExplicitModule";
791 
792         Out << "]";
793       }
794 
795       Out << "\n";
796 
797       return true;
798     }
799 
800     /// Returns true if this \c ASTReaderListener wants to receive the
801     /// imports of the AST file via \c visitImport, false otherwise.
802     bool needsImportVisitation() const override { return true; }
803 
804     /// If needsImportVisitation returns \c true, this is called for each
805     /// AST file imported by this AST file.
806     void visitImport(StringRef ModuleName, StringRef Filename) override {
807       Out.indent(2) << "Imports module '" << ModuleName
808                     << "': " << Filename.str() << "\n";
809     }
810 #undef DUMP_BOOLEAN
811   };
812 }
813 
814 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
815   // The Object file reader also supports raw ast files and there is no point in
816   // being strict about the module file format in -module-file-info mode.
817   CI.getHeaderSearchOpts().ModuleFormat = "obj";
818   return true;
819 }
820 
821 static StringRef ModuleKindName(Module::ModuleKind MK) {
822   switch (MK) {
823   case Module::ModuleMapModule:
824     return "Module Map Module";
825   case Module::ModuleInterfaceUnit:
826     return "Interface Unit";
827   case Module::ModuleImplementationUnit:
828     return "Implementation Unit";
829   case Module::ModulePartitionInterface:
830     return "Partition Interface";
831   case Module::ModulePartitionImplementation:
832     return "Partition Implementation";
833   case Module::ModuleHeaderUnit:
834     return "Header Unit";
835   case Module::ExplicitGlobalModuleFragment:
836     return "Global Module Fragment";
837   case Module::ImplicitGlobalModuleFragment:
838     return "Implicit Module Fragment";
839   case Module::PrivateModuleFragment:
840     return "Private Module Fragment";
841   }
842   llvm_unreachable("unknown module kind!");
843 }
844 
845 void DumpModuleInfoAction::ExecuteAction() {
846   assert(isCurrentFileAST() && "dumping non-AST?");
847   // Set up the output file.
848   CompilerInstance &CI = getCompilerInstance();
849   StringRef OutputFileName = CI.getFrontendOpts().OutputFile;
850   if (!OutputFileName.empty() && OutputFileName != "-") {
851     std::error_code EC;
852     OutputStream.reset(new llvm::raw_fd_ostream(
853         OutputFileName.str(), EC, llvm::sys::fs::OF_TextWithCRLF));
854   }
855   llvm::raw_ostream &Out = OutputStream ? *OutputStream : llvm::outs();
856 
857   Out << "Information for module file '" << getCurrentFile() << "':\n";
858   auto &FileMgr = CI.getFileManager();
859   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
860   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
861   bool IsRaw = Magic.starts_with("CPCH");
862   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
863 
864   Preprocessor &PP = CI.getPreprocessor();
865   DumpModuleInfoListener Listener(Out);
866   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
867 
868   // The FrontendAction::BeginSourceFile () method loads the AST so that much
869   // of the information is already available and modules should have been
870   // loaded.
871 
872   const LangOptions &LO = getCurrentASTUnit().getLangOpts();
873   if (LO.CPlusPlusModules && !LO.CurrentModule.empty()) {
874     ASTReader *R = getCurrentASTUnit().getASTReader().get();
875     unsigned SubModuleCount = R->getTotalNumSubmodules();
876     serialization::ModuleFile &MF = R->getModuleManager().getPrimaryModule();
877     Out << "  ====== C++20 Module structure ======\n";
878 
879     if (MF.ModuleName != LO.CurrentModule)
880       Out << "  Mismatched module names : " << MF.ModuleName << " and "
881           << LO.CurrentModule << "\n";
882 
883     struct SubModInfo {
884       unsigned Idx;
885       Module *Mod;
886       Module::ModuleKind Kind;
887       std::string &Name;
888       bool Seen;
889     };
890     std::map<std::string, SubModInfo> SubModMap;
891     auto PrintSubMapEntry = [&](std::string Name, Module::ModuleKind Kind) {
892       Out << "    " << ModuleKindName(Kind) << " '" << Name << "'";
893       auto I = SubModMap.find(Name);
894       if (I == SubModMap.end())
895         Out << " was not found in the sub modules!\n";
896       else {
897         I->second.Seen = true;
898         Out << " is at index #" << I->second.Idx << "\n";
899       }
900     };
901     Module *Primary = nullptr;
902     for (unsigned Idx = 0; Idx <= SubModuleCount; ++Idx) {
903       Module *M = R->getModule(Idx);
904       if (!M)
905         continue;
906       if (M->Name == LO.CurrentModule) {
907         Primary = M;
908         Out << "  " << ModuleKindName(M->Kind) << " '" << LO.CurrentModule
909             << "' is the Primary Module at index #" << Idx << "\n";
910         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, true}});
911       } else
912         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, false}});
913     }
914     if (Primary) {
915       if (!Primary->submodules().empty())
916         Out << "   Sub Modules:\n";
917       for (auto *MI : Primary->submodules()) {
918         PrintSubMapEntry(MI->Name, MI->Kind);
919       }
920       if (!Primary->Imports.empty())
921         Out << "   Imports:\n";
922       for (auto *IMP : Primary->Imports) {
923         PrintSubMapEntry(IMP->Name, IMP->Kind);
924       }
925       if (!Primary->Exports.empty())
926         Out << "   Exports:\n";
927       for (unsigned MN = 0, N = Primary->Exports.size(); MN != N; ++MN) {
928         if (Module *M = Primary->Exports[MN].getPointer()) {
929           PrintSubMapEntry(M->Name, M->Kind);
930         }
931       }
932     }
933 
934     // Emit the macro definitions in the module file so that we can know how
935     // much definitions in the module file quickly.
936     // TODO: Emit the macro definition bodies completely.
937     if (auto FilteredMacros = llvm::make_filter_range(
938             R->getPreprocessor().macros(),
939             [](const auto &Macro) { return Macro.first->isFromAST(); });
940         !FilteredMacros.empty()) {
941       Out << "   Macro Definitions:\n";
942       for (/*<IdentifierInfo *, MacroState> pair*/ const auto &Macro :
943            FilteredMacros)
944         Out << "     " << Macro.first->getName() << "\n";
945     }
946 
947     // Now let's print out any modules we did not see as part of the Primary.
948     for (const auto &SM : SubModMap) {
949       if (!SM.second.Seen && SM.second.Mod) {
950         Out << "  " << ModuleKindName(SM.second.Kind) << " '" << SM.first
951             << "' at index #" << SM.second.Idx
952             << " has no direct reference in the Primary\n";
953       }
954     }
955     Out << "  ====== ======\n";
956   }
957 
958   // The reminder of the output is produced from the listener as the AST
959   // FileCcontrolBlock is (re-)parsed.
960   ASTReader::readASTFileControlBlock(
961       getCurrentFile(), FileMgr, CI.getModuleCache(),
962       CI.getPCHContainerReader(),
963       /*FindModuleFileExtensions=*/true, Listener,
964       HSOpts.ModulesValidateDiagnosticOptions);
965 }
966 
967 //===----------------------------------------------------------------------===//
968 // Preprocessor Actions
969 //===----------------------------------------------------------------------===//
970 
971 void DumpRawTokensAction::ExecuteAction() {
972   Preprocessor &PP = getCompilerInstance().getPreprocessor();
973   SourceManager &SM = PP.getSourceManager();
974 
975   // Start lexing the specified input file.
976   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
977   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
978   RawLex.SetKeepWhitespaceMode(true);
979 
980   Token RawTok;
981   RawLex.LexFromRawLexer(RawTok);
982   while (RawTok.isNot(tok::eof)) {
983     PP.DumpToken(RawTok, true);
984     llvm::errs() << "\n";
985     RawLex.LexFromRawLexer(RawTok);
986   }
987 }
988 
989 void DumpTokensAction::ExecuteAction() {
990   Preprocessor &PP = getCompilerInstance().getPreprocessor();
991   // Start preprocessing the specified input file.
992   Token Tok;
993   PP.EnterMainSourceFile();
994   do {
995     PP.Lex(Tok);
996     PP.DumpToken(Tok, true);
997     llvm::errs() << "\n";
998   } while (Tok.isNot(tok::eof));
999 }
1000 
1001 void PreprocessOnlyAction::ExecuteAction() {
1002   Preprocessor &PP = getCompilerInstance().getPreprocessor();
1003 
1004   // Ignore unknown pragmas.
1005   PP.IgnorePragmas();
1006 
1007   Token Tok;
1008   // Start parsing the specified input file.
1009   PP.EnterMainSourceFile();
1010   do {
1011     PP.Lex(Tok);
1012   } while (Tok.isNot(tok::eof));
1013 }
1014 
1015 void PrintPreprocessedAction::ExecuteAction() {
1016   CompilerInstance &CI = getCompilerInstance();
1017   // Output file may need to be set to 'Binary', to avoid converting Unix style
1018   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>) on Windows.
1019   //
1020   // Look to see what type of line endings the file uses. If there's a
1021   // CRLF, then we won't open the file up in binary mode. If there is
1022   // just an LF or CR, then we will open the file up in binary mode.
1023   // In this fashion, the output format should match the input format, unless
1024   // the input format has inconsistent line endings.
1025   //
1026   // This should be a relatively fast operation since most files won't have
1027   // all of their source code on a single line. However, that is still a
1028   // concern, so if we scan for too long, we'll just assume the file should
1029   // be opened in binary mode.
1030 
1031   bool BinaryMode = false;
1032   if (llvm::Triple(LLVM_HOST_TRIPLE).isOSWindows()) {
1033     BinaryMode = true;
1034     const SourceManager &SM = CI.getSourceManager();
1035     if (std::optional<llvm::MemoryBufferRef> Buffer =
1036             SM.getBufferOrNone(SM.getMainFileID())) {
1037       const char *cur = Buffer->getBufferStart();
1038       const char *end = Buffer->getBufferEnd();
1039       const char *next = (cur != end) ? cur + 1 : end;
1040 
1041       // Limit ourselves to only scanning 256 characters into the source
1042       // file.  This is mostly a check in case the file has no
1043       // newlines whatsoever.
1044       if (end - cur > 256)
1045         end = cur + 256;
1046 
1047       while (next < end) {
1048         if (*cur == 0x0D) {  // CR
1049           if (*next == 0x0A) // CRLF
1050             BinaryMode = false;
1051 
1052           break;
1053         } else if (*cur == 0x0A) // LF
1054           break;
1055 
1056         ++cur;
1057         ++next;
1058       }
1059     }
1060   }
1061 
1062   std::unique_ptr<raw_ostream> OS =
1063       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
1064   if (!OS) return;
1065 
1066   // If we're preprocessing a module map, start by dumping the contents of the
1067   // module itself before switching to the input buffer.
1068   auto &Input = getCurrentInput();
1069   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
1070     if (Input.isFile()) {
1071       (*OS) << "# 1 \"";
1072       OS->write_escaped(Input.getFile());
1073       (*OS) << "\"\n";
1074     }
1075     getCurrentModule()->print(*OS);
1076     (*OS) << "#pragma clang module contents\n";
1077   }
1078 
1079   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
1080                            CI.getPreprocessorOutputOpts());
1081 }
1082 
1083 void PrintPreambleAction::ExecuteAction() {
1084   switch (getCurrentFileKind().getLanguage()) {
1085   case Language::C:
1086   case Language::CXX:
1087   case Language::ObjC:
1088   case Language::ObjCXX:
1089   case Language::OpenCL:
1090   case Language::OpenCLCXX:
1091   case Language::CUDA:
1092   case Language::HIP:
1093   case Language::HLSL:
1094   case Language::CIR:
1095     break;
1096 
1097   case Language::Unknown:
1098   case Language::Asm:
1099   case Language::LLVM_IR:
1100   case Language::RenderScript:
1101     // We can't do anything with these.
1102     return;
1103   }
1104 
1105   // We don't expect to find any #include directives in a preprocessed input.
1106   if (getCurrentFileKind().isPreprocessed())
1107     return;
1108 
1109   CompilerInstance &CI = getCompilerInstance();
1110   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
1111   if (Buffer) {
1112     unsigned Preamble =
1113         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
1114     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
1115   }
1116 }
1117 
1118 void DumpCompilerOptionsAction::ExecuteAction() {
1119   CompilerInstance &CI = getCompilerInstance();
1120   std::unique_ptr<raw_ostream> OSP =
1121       CI.createDefaultOutputFile(false, getCurrentFile());
1122   if (!OSP)
1123     return;
1124 
1125   raw_ostream &OS = *OSP;
1126   const Preprocessor &PP = CI.getPreprocessor();
1127   const LangOptions &LangOpts = PP.getLangOpts();
1128 
1129   // FIXME: Rather than manually format the JSON (which is awkward due to
1130   // needing to remove trailing commas), this should make use of a JSON library.
1131   // FIXME: Instead of printing enums as an integral value and specifying the
1132   // type as a separate field, use introspection to print the enumerator.
1133 
1134   OS << "{\n";
1135   OS << "\n\"features\" : [\n";
1136   {
1137     llvm::SmallString<128> Str;
1138 #define FEATURE(Name, Predicate)                                               \
1139   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1140       .toVector(Str);
1141 #include "clang/Basic/Features.def"
1142 #undef FEATURE
1143     // Remove the newline and comma from the last entry to ensure this remains
1144     // valid JSON.
1145     OS << Str.substr(0, Str.size() - 2);
1146   }
1147   OS << "\n],\n";
1148 
1149   OS << "\n\"extensions\" : [\n";
1150   {
1151     llvm::SmallString<128> Str;
1152 #define EXTENSION(Name, Predicate)                                             \
1153   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1154       .toVector(Str);
1155 #include "clang/Basic/Features.def"
1156 #undef EXTENSION
1157     // Remove the newline and comma from the last entry to ensure this remains
1158     // valid JSON.
1159     OS << Str.substr(0, Str.size() - 2);
1160   }
1161   OS << "\n]\n";
1162 
1163   OS << "}";
1164 }
1165 
1166 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
1167   CompilerInstance &CI = getCompilerInstance();
1168   SourceManager &SM = CI.getPreprocessor().getSourceManager();
1169   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
1170 
1171   llvm::SmallVector<dependency_directives_scan::Token, 16> Tokens;
1172   llvm::SmallVector<dependency_directives_scan::Directive, 32> Directives;
1173   if (scanSourceForDependencyDirectives(
1174           FromFile.getBuffer(), Tokens, Directives, &CI.getDiagnostics(),
1175           SM.getLocForStartOfFile(SM.getMainFileID()))) {
1176     assert(CI.getDiagnostics().hasErrorOccurred() &&
1177            "no errors reported for failure");
1178 
1179     // Preprocess the source when verifying the diagnostics to capture the
1180     // 'expected' comments.
1181     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
1182       // Make sure we don't emit new diagnostics!
1183       CI.getDiagnostics().setSuppressAllDiagnostics(true);
1184       Preprocessor &PP = getCompilerInstance().getPreprocessor();
1185       PP.EnterMainSourceFile();
1186       Token Tok;
1187       do {
1188         PP.Lex(Tok);
1189       } while (Tok.isNot(tok::eof));
1190     }
1191     return;
1192   }
1193   printDependencyDirectivesAsSource(FromFile.getBuffer(), Directives,
1194                                     llvm::outs());
1195 }
1196 
1197 void GetDependenciesByModuleNameAction::ExecuteAction() {
1198   CompilerInstance &CI = getCompilerInstance();
1199   Preprocessor &PP = CI.getPreprocessor();
1200   SourceManager &SM = PP.getSourceManager();
1201   FileID MainFileID = SM.getMainFileID();
1202   SourceLocation FileStart = SM.getLocForStartOfFile(MainFileID);
1203   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1204   IdentifierInfo *ModuleID = PP.getIdentifierInfo(ModuleName);
1205   Path.push_back(std::make_pair(ModuleID, FileStart));
1206   auto ModResult = CI.loadModule(FileStart, Path, Module::Hidden, false);
1207   PPCallbacks *CB = PP.getPPCallbacks();
1208   CB->moduleImport(SourceLocation(), Path, ModResult);
1209 }
1210