xref: /llvm-project/clang/lib/Frontend/FrontendActions.cpp (revision 6213aa5e58a7d32bdc82dd40322fb1bab83c4783)
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/Config/llvm-config.h" // for LLVM_HOST_TRIPLE
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/FileSystem.h"
32 #include "llvm/Support/MemoryBuffer.h"
33 #include "llvm/Support/Path.h"
34 #include "llvm/Support/YAMLTraits.h"
35 #include "llvm/Support/raw_ostream.h"
36 #include <memory>
37 #include <optional>
38 #include <system_error>
39 
40 using namespace clang;
41 
42 namespace {
43 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
44   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
45                                         : nullptr;
46 }
47 
48 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
49   if (Action.hasCodeCompletionSupport() &&
50       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
51     CI.createCodeCompletionConsumer();
52 
53   if (!CI.hasSema())
54     CI.createSema(Action.getTranslationUnitKind(),
55                   GetCodeCompletionConsumer(CI));
56 }
57 } // namespace
58 
59 //===----------------------------------------------------------------------===//
60 // Custom Actions
61 //===----------------------------------------------------------------------===//
62 
63 std::unique_ptr<ASTConsumer>
64 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
65   return std::make_unique<ASTConsumer>();
66 }
67 
68 void InitOnlyAction::ExecuteAction() {
69 }
70 
71 // Basically PreprocessOnlyAction::ExecuteAction.
72 void ReadPCHAndPreprocessAction::ExecuteAction() {
73   Preprocessor &PP = getCompilerInstance().getPreprocessor();
74 
75   // Ignore unknown pragmas.
76   PP.IgnorePragmas();
77 
78   Token Tok;
79   // Start parsing the specified input file.
80   PP.EnterMainSourceFile();
81   do {
82     PP.Lex(Tok);
83   } while (Tok.isNot(tok::eof));
84 }
85 
86 std::unique_ptr<ASTConsumer>
87 ReadPCHAndPreprocessAction::CreateASTConsumer(CompilerInstance &CI,
88                                               StringRef InFile) {
89   return std::make_unique<ASTConsumer>();
90 }
91 
92 //===----------------------------------------------------------------------===//
93 // AST Consumer Actions
94 //===----------------------------------------------------------------------===//
95 
96 std::unique_ptr<ASTConsumer>
97 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
98   if (std::unique_ptr<raw_ostream> OS =
99           CI.createDefaultOutputFile(false, InFile))
100     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
101   return nullptr;
102 }
103 
104 std::unique_ptr<ASTConsumer>
105 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
106   const FrontendOptions &Opts = CI.getFrontendOpts();
107   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
108                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
109                          Opts.ASTDumpLookups, Opts.ASTDumpDeclTypes,
110                          Opts.ASTDumpFormat);
111 }
112 
113 std::unique_ptr<ASTConsumer>
114 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
115   return CreateASTDeclNodeLister();
116 }
117 
118 std::unique_ptr<ASTConsumer>
119 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
120   return CreateASTViewer();
121 }
122 
123 std::unique_ptr<ASTConsumer>
124 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
125   std::string Sysroot;
126   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
127     return nullptr;
128 
129   std::string OutputFile;
130   std::unique_ptr<raw_pwrite_stream> OS =
131       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
132   if (!OS)
133     return nullptr;
134 
135   if (!CI.getFrontendOpts().RelocatablePCH)
136     Sysroot.clear();
137 
138   const auto &FrontendOpts = CI.getFrontendOpts();
139   auto Buffer = std::make_shared<PCHBuffer>();
140   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
141   Consumers.push_back(std::make_unique<PCHGenerator>(
142       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
143       FrontendOpts.ModuleFileExtensions,
144       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
145       FrontendOpts.IncludeTimestamps, FrontendOpts.BuildingImplicitModule,
146       +CI.getLangOpts().CacheGeneratedPCH));
147   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
148       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
149 
150   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
151 }
152 
153 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
154                                                     std::string &Sysroot) {
155   Sysroot = CI.getHeaderSearchOpts().Sysroot;
156   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
157     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
158     return false;
159   }
160 
161   return true;
162 }
163 
164 std::unique_ptr<llvm::raw_pwrite_stream>
165 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
166                                     std::string &OutputFile) {
167   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
168   std::unique_ptr<raw_pwrite_stream> OS = CI.createDefaultOutputFile(
169       /*Binary=*/true, InFile, /*Extension=*/"", /*RemoveFileOnSignal=*/false);
170   if (!OS)
171     return nullptr;
172 
173   OutputFile = CI.getFrontendOpts().OutputFile;
174   return OS;
175 }
176 
177 bool GeneratePCHAction::shouldEraseOutputFiles() {
178   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
179     return false;
180   return ASTFrontendAction::shouldEraseOutputFiles();
181 }
182 
183 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
184   CI.getLangOpts().CompilingPCH = true;
185   return true;
186 }
187 
188 std::vector<std::unique_ptr<ASTConsumer>>
189 GenerateModuleAction::CreateMultiplexConsumer(CompilerInstance &CI,
190                                               StringRef InFile) {
191   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
192   if (!OS)
193     return {};
194 
195   std::string OutputFile = CI.getFrontendOpts().OutputFile;
196   std::string Sysroot;
197 
198   auto Buffer = std::make_shared<PCHBuffer>();
199   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
200 
201   Consumers.push_back(std::make_unique<PCHGenerator>(
202       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
203       CI.getFrontendOpts().ModuleFileExtensions,
204       /*AllowASTWithErrors=*/
205       +CI.getFrontendOpts().AllowPCMWithCompilerErrors,
206       /*IncludeTimestamps=*/
207       +CI.getFrontendOpts().BuildingImplicitModule &&
208           +CI.getFrontendOpts().IncludeTimestamps,
209       /*BuildingImplicitModule=*/+CI.getFrontendOpts().BuildingImplicitModule,
210       /*ShouldCacheASTInMemory=*/
211       +CI.getFrontendOpts().BuildingImplicitModule));
212   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
213       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
214   return Consumers;
215 }
216 
217 std::unique_ptr<ASTConsumer>
218 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
219                                         StringRef InFile) {
220   std::vector<std::unique_ptr<ASTConsumer>> Consumers =
221       CreateMultiplexConsumer(CI, InFile);
222   if (Consumers.empty())
223     return nullptr;
224 
225   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
226 }
227 
228 bool GenerateModuleAction::shouldEraseOutputFiles() {
229   return !getCompilerInstance().getFrontendOpts().AllowPCMWithCompilerErrors &&
230          ASTFrontendAction::shouldEraseOutputFiles();
231 }
232 
233 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
234     CompilerInstance &CI) {
235   if (!CI.getLangOpts().Modules) {
236     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
237     return false;
238   }
239 
240   return GenerateModuleAction::BeginSourceFileAction(CI);
241 }
242 
243 std::unique_ptr<raw_pwrite_stream>
244 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
245                                                     StringRef InFile) {
246   // If no output file was provided, figure out where this module would go
247   // in the module cache.
248   if (CI.getFrontendOpts().OutputFile.empty()) {
249     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
250     if (ModuleMapFile.empty())
251       ModuleMapFile = InFile;
252 
253     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
254     CI.getFrontendOpts().OutputFile =
255         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
256                                    ModuleMapFile);
257   }
258 
259   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
260   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, /*Extension=*/"",
261                                     /*RemoveFileOnSignal=*/false,
262                                     /*CreateMissingDirectories=*/true,
263                                     /*ForceUseTemporary=*/true);
264 }
265 
266 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
267     CompilerInstance &CI) {
268   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
269 
270   return GenerateModuleAction::BeginSourceFileAction(CI);
271 }
272 
273 std::unique_ptr<ASTConsumer>
274 GenerateModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
275                                                  StringRef InFile) {
276   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
277 
278   if (CI.getFrontendOpts().GenReducedBMI &&
279       !CI.getFrontendOpts().ModuleOutputPath.empty()) {
280     Consumers.push_back(std::make_unique<ReducedBMIGenerator>(
281         CI.getPreprocessor(), CI.getModuleCache(),
282         CI.getFrontendOpts().ModuleOutputPath));
283   }
284 
285   Consumers.push_back(std::make_unique<CXX20ModulesGenerator>(
286       CI.getPreprocessor(), CI.getModuleCache(),
287       CI.getFrontendOpts().OutputFile));
288 
289   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
290 }
291 
292 std::unique_ptr<raw_pwrite_stream>
293 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
294                                                 StringRef InFile) {
295   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
296 }
297 
298 std::unique_ptr<ASTConsumer>
299 GenerateReducedModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
300                                                         StringRef InFile) {
301   return std::make_unique<ReducedBMIGenerator>(CI.getPreprocessor(),
302                                                CI.getModuleCache(),
303                                                CI.getFrontendOpts().OutputFile);
304 }
305 
306 bool GenerateHeaderUnitAction::BeginSourceFileAction(CompilerInstance &CI) {
307   if (!CI.getLangOpts().CPlusPlusModules) {
308     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
309     return false;
310   }
311   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderUnit);
312   return GenerateModuleAction::BeginSourceFileAction(CI);
313 }
314 
315 std::unique_ptr<raw_pwrite_stream>
316 GenerateHeaderUnitAction::CreateOutputFile(CompilerInstance &CI,
317                                            StringRef InFile) {
318   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
319 }
320 
321 SyntaxOnlyAction::~SyntaxOnlyAction() {
322 }
323 
324 std::unique_ptr<ASTConsumer>
325 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
326   return std::make_unique<ASTConsumer>();
327 }
328 
329 std::unique_ptr<ASTConsumer>
330 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
331                                         StringRef InFile) {
332   return std::make_unique<ASTConsumer>();
333 }
334 
335 std::unique_ptr<ASTConsumer>
336 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
337   return std::make_unique<ASTConsumer>();
338 }
339 
340 void VerifyPCHAction::ExecuteAction() {
341   CompilerInstance &CI = getCompilerInstance();
342   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
343   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
344   std::unique_ptr<ASTReader> Reader(new ASTReader(
345       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
346       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
347       Sysroot.empty() ? "" : Sysroot.c_str(),
348       DisableValidationForModuleKind::None,
349       /*AllowASTWithCompilerErrors*/ false,
350       /*AllowConfigurationMismatch*/ true,
351       /*ValidateSystemInputs*/ true));
352 
353   Reader->ReadAST(getCurrentFile(),
354                   Preamble ? serialization::MK_Preamble
355                            : serialization::MK_PCH,
356                   SourceLocation(),
357                   ASTReader::ARR_ConfigurationMismatch);
358 }
359 
360 namespace {
361 struct TemplightEntry {
362   std::string Name;
363   std::string Kind;
364   std::string Event;
365   std::string DefinitionLocation;
366   std::string PointOfInstantiation;
367 };
368 } // namespace
369 
370 namespace llvm {
371 namespace yaml {
372 template <> struct MappingTraits<TemplightEntry> {
373   static void mapping(IO &io, TemplightEntry &fields) {
374     io.mapRequired("name", fields.Name);
375     io.mapRequired("kind", fields.Kind);
376     io.mapRequired("event", fields.Event);
377     io.mapRequired("orig", fields.DefinitionLocation);
378     io.mapRequired("poi", fields.PointOfInstantiation);
379   }
380 };
381 } // namespace yaml
382 } // namespace llvm
383 
384 namespace {
385 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
386   using CodeSynthesisContext = Sema::CodeSynthesisContext;
387 
388 public:
389   void initialize(const Sema &) override {}
390 
391   void finalize(const Sema &) override {}
392 
393   void atTemplateBegin(const Sema &TheSema,
394                        const CodeSynthesisContext &Inst) override {
395     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
396   }
397 
398   void atTemplateEnd(const Sema &TheSema,
399                      const CodeSynthesisContext &Inst) override {
400     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
401   }
402 
403 private:
404   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
405     switch (Kind) {
406     case CodeSynthesisContext::TemplateInstantiation:
407       return "TemplateInstantiation";
408     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
409       return "DefaultTemplateArgumentInstantiation";
410     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
411       return "DefaultFunctionArgumentInstantiation";
412     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
413       return "ExplicitTemplateArgumentSubstitution";
414     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
415       return "DeducedTemplateArgumentSubstitution";
416     case CodeSynthesisContext::LambdaExpressionSubstitution:
417       return "LambdaExpressionSubstitution";
418     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
419       return "PriorTemplateArgumentSubstitution";
420     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
421       return "DefaultTemplateArgumentChecking";
422     case CodeSynthesisContext::ExceptionSpecEvaluation:
423       return "ExceptionSpecEvaluation";
424     case CodeSynthesisContext::ExceptionSpecInstantiation:
425       return "ExceptionSpecInstantiation";
426     case CodeSynthesisContext::DeclaringSpecialMember:
427       return "DeclaringSpecialMember";
428     case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
429       return "DeclaringImplicitEqualityComparison";
430     case CodeSynthesisContext::DefiningSynthesizedFunction:
431       return "DefiningSynthesizedFunction";
432     case CodeSynthesisContext::RewritingOperatorAsSpaceship:
433       return "RewritingOperatorAsSpaceship";
434     case CodeSynthesisContext::Memoization:
435       return "Memoization";
436     case CodeSynthesisContext::ConstraintsCheck:
437       return "ConstraintsCheck";
438     case CodeSynthesisContext::ConstraintSubstitution:
439       return "ConstraintSubstitution";
440     case CodeSynthesisContext::ConstraintNormalization:
441       return "ConstraintNormalization";
442     case CodeSynthesisContext::RequirementParameterInstantiation:
443       return "RequirementParameterInstantiation";
444     case CodeSynthesisContext::ParameterMappingSubstitution:
445       return "ParameterMappingSubstitution";
446     case CodeSynthesisContext::RequirementInstantiation:
447       return "RequirementInstantiation";
448     case CodeSynthesisContext::NestedRequirementConstraintsCheck:
449       return "NestedRequirementConstraintsCheck";
450     case CodeSynthesisContext::InitializingStructuredBinding:
451       return "InitializingStructuredBinding";
452     case CodeSynthesisContext::MarkingClassDllexported:
453       return "MarkingClassDllexported";
454     case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
455       return "BuildingBuiltinDumpStructCall";
456     case CodeSynthesisContext::BuildingDeductionGuides:
457       return "BuildingDeductionGuides";
458     case CodeSynthesisContext::TypeAliasTemplateInstantiation:
459       return "TypeAliasTemplateInstantiation";
460     case CodeSynthesisContext::PartialOrderingTTP:
461       return "PartialOrderingTTP";
462     }
463     return "";
464   }
465 
466   template <bool BeginInstantiation>
467   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
468                                     const CodeSynthesisContext &Inst) {
469     std::string YAML;
470     {
471       llvm::raw_string_ostream OS(YAML);
472       llvm::yaml::Output YO(OS);
473       TemplightEntry Entry =
474           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
475       llvm::yaml::EmptyContext Context;
476       llvm::yaml::yamlize(YO, Entry, true, Context);
477     }
478     Out << "---" << YAML << "\n";
479   }
480 
481   static void printEntryName(const Sema &TheSema, const Decl *Entity,
482                              llvm::raw_string_ostream &OS) {
483     auto *NamedTemplate = cast<NamedDecl>(Entity);
484 
485     PrintingPolicy Policy = TheSema.Context.getPrintingPolicy();
486     // FIXME: Also ask for FullyQualifiedNames?
487     Policy.SuppressDefaultTemplateArgs = false;
488     NamedTemplate->getNameForDiagnostic(OS, Policy, true);
489 
490     if (!OS.str().empty())
491       return;
492 
493     Decl *Ctx = Decl::castFromDeclContext(NamedTemplate->getDeclContext());
494     NamedDecl *NamedCtx = dyn_cast_or_null<NamedDecl>(Ctx);
495 
496     if (const auto *Decl = dyn_cast<TagDecl>(NamedTemplate)) {
497       if (const auto *R = dyn_cast<RecordDecl>(Decl)) {
498         if (R->isLambda()) {
499           OS << "lambda at ";
500           Decl->getLocation().print(OS, TheSema.getSourceManager());
501           return;
502         }
503       }
504       OS << "unnamed " << Decl->getKindName();
505       return;
506     }
507 
508     assert(NamedCtx && "NamedCtx cannot be null");
509 
510     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
511       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
512          << " ";
513       if (Decl->getFunctionScopeDepth() > 0)
514         OS << "(at depth " << Decl->getFunctionScopeDepth() << ") ";
515       OS << "of ";
516       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
517       return;
518     }
519 
520     if (const auto *Decl = dyn_cast<TemplateTypeParmDecl>(NamedTemplate)) {
521       if (const Type *Ty = Decl->getTypeForDecl()) {
522         if (const auto *TTPT = dyn_cast_or_null<TemplateTypeParmType>(Ty)) {
523           OS << "unnamed template type parameter " << TTPT->getIndex() << " ";
524           if (TTPT->getDepth() > 0)
525             OS << "(at depth " << TTPT->getDepth() << ") ";
526           OS << "of ";
527           NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
528           return;
529         }
530       }
531     }
532 
533     if (const auto *Decl = dyn_cast<NonTypeTemplateParmDecl>(NamedTemplate)) {
534       OS << "unnamed template non-type parameter " << Decl->getIndex() << " ";
535       if (Decl->getDepth() > 0)
536         OS << "(at depth " << Decl->getDepth() << ") ";
537       OS << "of ";
538       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
539       return;
540     }
541 
542     if (const auto *Decl = dyn_cast<TemplateTemplateParmDecl>(NamedTemplate)) {
543       OS << "unnamed template template parameter " << Decl->getIndex() << " ";
544       if (Decl->getDepth() > 0)
545         OS << "(at depth " << Decl->getDepth() << ") ";
546       OS << "of ";
547       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
548       return;
549     }
550 
551     llvm_unreachable("Failed to retrieve a name for this entry!");
552     OS << "unnamed identifier";
553   }
554 
555   template <bool BeginInstantiation>
556   static TemplightEntry getTemplightEntry(const Sema &TheSema,
557                                           const CodeSynthesisContext &Inst) {
558     TemplightEntry Entry;
559     Entry.Kind = toString(Inst.Kind);
560     Entry.Event = BeginInstantiation ? "Begin" : "End";
561     llvm::raw_string_ostream OS(Entry.Name);
562     printEntryName(TheSema, Inst.Entity, OS);
563     const PresumedLoc DefLoc =
564         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
565     if (!DefLoc.isInvalid())
566       Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
567                                  std::to_string(DefLoc.getLine()) + ":" +
568                                  std::to_string(DefLoc.getColumn());
569     const PresumedLoc PoiLoc =
570         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
571     if (!PoiLoc.isInvalid()) {
572       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
573                                    std::to_string(PoiLoc.getLine()) + ":" +
574                                    std::to_string(PoiLoc.getColumn());
575     }
576     return Entry;
577   }
578 };
579 } // namespace
580 
581 std::unique_ptr<ASTConsumer>
582 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
583   return std::make_unique<ASTConsumer>();
584 }
585 
586 void TemplightDumpAction::ExecuteAction() {
587   CompilerInstance &CI = getCompilerInstance();
588 
589   // This part is normally done by ASTFrontEndAction, but needs to happen
590   // before Templight observers can be created
591   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
592   // here so the source manager would be initialized.
593   EnsureSemaIsCreated(CI, *this);
594 
595   CI.getSema().TemplateInstCallbacks.push_back(
596       std::make_unique<DefaultTemplateInstCallback>());
597   ASTFrontendAction::ExecuteAction();
598 }
599 
600 namespace {
601   /// AST reader listener that dumps module information for a module
602   /// file.
603   class DumpModuleInfoListener : public ASTReaderListener {
604     llvm::raw_ostream &Out;
605 
606   public:
607     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
608 
609 #define DUMP_BOOLEAN(Value, Text)                       \
610     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
611 
612     bool ReadFullVersionInformation(StringRef FullVersion) override {
613       Out.indent(2)
614         << "Generated by "
615         << (FullVersion == getClangFullRepositoryVersion()? "this"
616                                                           : "a different")
617         << " Clang: " << FullVersion << "\n";
618       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
619     }
620 
621     void ReadModuleName(StringRef ModuleName) override {
622       Out.indent(2) << "Module name: " << ModuleName << "\n";
623     }
624     void ReadModuleMapFile(StringRef ModuleMapPath) override {
625       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
626     }
627 
628     bool ReadLanguageOptions(const LangOptions &LangOpts,
629                              StringRef ModuleFilename, bool Complain,
630                              bool AllowCompatibleDifferences) override {
631       Out.indent(2) << "Language options:\n";
632 #define LANGOPT(Name, Bits, Default, Description) \
633       DUMP_BOOLEAN(LangOpts.Name, Description);
634 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
635       Out.indent(4) << Description << ": "                   \
636                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
637 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
638       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
639 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
640 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
641 #include "clang/Basic/LangOptions.def"
642 
643       if (!LangOpts.ModuleFeatures.empty()) {
644         Out.indent(4) << "Module features:\n";
645         for (StringRef Feature : LangOpts.ModuleFeatures)
646           Out.indent(6) << Feature << "\n";
647       }
648 
649       return false;
650     }
651 
652     bool ReadTargetOptions(const TargetOptions &TargetOpts,
653                            StringRef ModuleFilename, bool Complain,
654                            bool AllowCompatibleDifferences) override {
655       Out.indent(2) << "Target options:\n";
656       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
657       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
658       Out.indent(4) << "  TuneCPU: " << TargetOpts.TuneCPU << "\n";
659       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
660 
661       if (!TargetOpts.FeaturesAsWritten.empty()) {
662         Out.indent(4) << "Target features:\n";
663         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
664              I != N; ++I) {
665           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
666         }
667       }
668 
669       return false;
670     }
671 
672     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
673                                StringRef ModuleFilename,
674                                bool Complain) override {
675       Out.indent(2) << "Diagnostic options:\n";
676 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
677 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
678       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
679 #define VALUE_DIAGOPT(Name, Bits, Default) \
680       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
681 #include "clang/Basic/DiagnosticOptions.def"
682 
683       Out.indent(4) << "Diagnostic flags:\n";
684       for (const std::string &Warning : DiagOpts->Warnings)
685         Out.indent(6) << "-W" << Warning << "\n";
686       for (const std::string &Remark : DiagOpts->Remarks)
687         Out.indent(6) << "-R" << Remark << "\n";
688 
689       return false;
690     }
691 
692     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
693                                  StringRef ModuleFilename,
694                                  StringRef SpecificModuleCachePath,
695                                  bool Complain) override {
696       Out.indent(2) << "Header search options:\n";
697       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
698       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
699       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
700       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
701                    "Use builtin include directories [-nobuiltininc]");
702       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
703                    "Use standard system include directories [-nostdinc]");
704       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
705                    "Use standard C++ include directories [-nostdinc++]");
706       DUMP_BOOLEAN(HSOpts.UseLibcxx,
707                    "Use libc++ (rather than libstdc++) [-stdlib=]");
708       return false;
709     }
710 
711     bool ReadHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
712                                bool Complain) override {
713       Out.indent(2) << "Header search paths:\n";
714       Out.indent(4) << "User entries:\n";
715       for (const auto &Entry : HSOpts.UserEntries)
716         Out.indent(6) << Entry.Path << "\n";
717       Out.indent(4) << "System header prefixes:\n";
718       for (const auto &Prefix : HSOpts.SystemHeaderPrefixes)
719         Out.indent(6) << Prefix.Prefix << "\n";
720       Out.indent(4) << "VFS overlay files:\n";
721       for (const auto &Overlay : HSOpts.VFSOverlayFiles)
722         Out.indent(6) << Overlay << "\n";
723       return false;
724     }
725 
726     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
727                                  StringRef ModuleFilename, bool ReadMacros,
728                                  bool Complain,
729                                  std::string &SuggestedPredefines) override {
730       Out.indent(2) << "Preprocessor options:\n";
731       DUMP_BOOLEAN(PPOpts.UsePredefines,
732                    "Uses compiler/target-specific predefines [-undef]");
733       DUMP_BOOLEAN(PPOpts.DetailedRecord,
734                    "Uses detailed preprocessing record (for indexing)");
735 
736       if (ReadMacros) {
737         Out.indent(4) << "Predefined macros:\n";
738       }
739 
740       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
741              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
742            I != IEnd; ++I) {
743         Out.indent(6);
744         if (I->second)
745           Out << "-U";
746         else
747           Out << "-D";
748         Out << I->first << "\n";
749       }
750       return false;
751     }
752 
753     /// Indicates that a particular module file extension has been read.
754     void readModuleFileExtension(
755            const ModuleFileExtensionMetadata &Metadata) override {
756       Out.indent(2) << "Module file extension '"
757                     << Metadata.BlockName << "' " << Metadata.MajorVersion
758                     << "." << Metadata.MinorVersion;
759       if (!Metadata.UserInfo.empty()) {
760         Out << ": ";
761         Out.write_escaped(Metadata.UserInfo);
762       }
763 
764       Out << "\n";
765     }
766 
767     /// Tells the \c ASTReaderListener that we want to receive the
768     /// input files of the AST file via \c visitInputFile.
769     bool needsInputFileVisitation() override { return true; }
770 
771     /// Tells the \c ASTReaderListener that we want to receive the
772     /// input files of the AST file via \c visitInputFile.
773     bool needsSystemInputFileVisitation() override { return true; }
774 
775     /// Indicates that the AST file contains particular input file.
776     ///
777     /// \returns true to continue receiving the next input file, false to stop.
778     bool visitInputFile(StringRef Filename, bool isSystem,
779                         bool isOverridden, bool isExplicitModule) override {
780 
781       Out.indent(2) << "Input file: " << Filename;
782 
783       if (isSystem || isOverridden || isExplicitModule) {
784         Out << " [";
785         if (isSystem) {
786           Out << "System";
787           if (isOverridden || isExplicitModule)
788             Out << ", ";
789         }
790         if (isOverridden) {
791           Out << "Overridden";
792           if (isExplicitModule)
793             Out << ", ";
794         }
795         if (isExplicitModule)
796           Out << "ExplicitModule";
797 
798         Out << "]";
799       }
800 
801       Out << "\n";
802 
803       return true;
804     }
805 
806     /// Returns true if this \c ASTReaderListener wants to receive the
807     /// imports of the AST file via \c visitImport, false otherwise.
808     bool needsImportVisitation() const override { return true; }
809 
810     /// If needsImportVisitation returns \c true, this is called for each
811     /// AST file imported by this AST file.
812     void visitImport(StringRef ModuleName, StringRef Filename) override {
813       Out.indent(2) << "Imports module '" << ModuleName
814                     << "': " << Filename.str() << "\n";
815     }
816 #undef DUMP_BOOLEAN
817   };
818 }
819 
820 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
821   // The Object file reader also supports raw ast files and there is no point in
822   // being strict about the module file format in -module-file-info mode.
823   CI.getHeaderSearchOpts().ModuleFormat = "obj";
824   return true;
825 }
826 
827 static StringRef ModuleKindName(Module::ModuleKind MK) {
828   switch (MK) {
829   case Module::ModuleMapModule:
830     return "Module Map Module";
831   case Module::ModuleInterfaceUnit:
832     return "Interface Unit";
833   case Module::ModuleImplementationUnit:
834     return "Implementation Unit";
835   case Module::ModulePartitionInterface:
836     return "Partition Interface";
837   case Module::ModulePartitionImplementation:
838     return "Partition Implementation";
839   case Module::ModuleHeaderUnit:
840     return "Header Unit";
841   case Module::ExplicitGlobalModuleFragment:
842     return "Global Module Fragment";
843   case Module::ImplicitGlobalModuleFragment:
844     return "Implicit Module Fragment";
845   case Module::PrivateModuleFragment:
846     return "Private Module Fragment";
847   }
848   llvm_unreachable("unknown module kind!");
849 }
850 
851 void DumpModuleInfoAction::ExecuteAction() {
852   CompilerInstance &CI = getCompilerInstance();
853 
854   // Don't process files of type other than module to avoid crash
855   if (!isCurrentFileAST()) {
856     CI.getDiagnostics().Report(diag::err_file_is_not_module)
857         << getCurrentFile();
858     return;
859   }
860 
861   // Set up the output file.
862   StringRef OutputFileName = CI.getFrontendOpts().OutputFile;
863   if (!OutputFileName.empty() && OutputFileName != "-") {
864     std::error_code EC;
865     OutputStream.reset(new llvm::raw_fd_ostream(
866         OutputFileName.str(), EC, llvm::sys::fs::OF_TextWithCRLF));
867   }
868   llvm::raw_ostream &Out = OutputStream ? *OutputStream : llvm::outs();
869 
870   Out << "Information for module file '" << getCurrentFile() << "':\n";
871   auto &FileMgr = CI.getFileManager();
872   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
873   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
874   bool IsRaw = Magic.starts_with("CPCH");
875   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
876 
877   Preprocessor &PP = CI.getPreprocessor();
878   DumpModuleInfoListener Listener(Out);
879   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
880 
881   // The FrontendAction::BeginSourceFile () method loads the AST so that much
882   // of the information is already available and modules should have been
883   // loaded.
884 
885   const LangOptions &LO = getCurrentASTUnit().getLangOpts();
886   if (LO.CPlusPlusModules && !LO.CurrentModule.empty()) {
887     ASTReader *R = getCurrentASTUnit().getASTReader().get();
888     unsigned SubModuleCount = R->getTotalNumSubmodules();
889     serialization::ModuleFile &MF = R->getModuleManager().getPrimaryModule();
890     Out << "  ====== C++20 Module structure ======\n";
891 
892     if (MF.ModuleName != LO.CurrentModule)
893       Out << "  Mismatched module names : " << MF.ModuleName << " and "
894           << LO.CurrentModule << "\n";
895 
896     struct SubModInfo {
897       unsigned Idx;
898       Module *Mod;
899       Module::ModuleKind Kind;
900       std::string &Name;
901       bool Seen;
902     };
903     std::map<std::string, SubModInfo> SubModMap;
904     auto PrintSubMapEntry = [&](std::string Name, Module::ModuleKind Kind) {
905       Out << "    " << ModuleKindName(Kind) << " '" << Name << "'";
906       auto I = SubModMap.find(Name);
907       if (I == SubModMap.end())
908         Out << " was not found in the sub modules!\n";
909       else {
910         I->second.Seen = true;
911         Out << " is at index #" << I->second.Idx << "\n";
912       }
913     };
914     Module *Primary = nullptr;
915     for (unsigned Idx = 0; Idx <= SubModuleCount; ++Idx) {
916       Module *M = R->getModule(Idx);
917       if (!M)
918         continue;
919       if (M->Name == LO.CurrentModule) {
920         Primary = M;
921         Out << "  " << ModuleKindName(M->Kind) << " '" << LO.CurrentModule
922             << "' is the Primary Module at index #" << Idx << "\n";
923         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, true}});
924       } else
925         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, false}});
926     }
927     if (Primary) {
928       if (!Primary->submodules().empty())
929         Out << "   Sub Modules:\n";
930       for (auto *MI : Primary->submodules()) {
931         PrintSubMapEntry(MI->Name, MI->Kind);
932       }
933       if (!Primary->Imports.empty())
934         Out << "   Imports:\n";
935       for (auto *IMP : Primary->Imports) {
936         PrintSubMapEntry(IMP->Name, IMP->Kind);
937       }
938       if (!Primary->Exports.empty())
939         Out << "   Exports:\n";
940       for (unsigned MN = 0, N = Primary->Exports.size(); MN != N; ++MN) {
941         if (Module *M = Primary->Exports[MN].getPointer()) {
942           PrintSubMapEntry(M->Name, M->Kind);
943         }
944       }
945     }
946 
947     // Emit the macro definitions in the module file so that we can know how
948     // much definitions in the module file quickly.
949     // TODO: Emit the macro definition bodies completely.
950     if (auto FilteredMacros = llvm::make_filter_range(
951             R->getPreprocessor().macros(),
952             [](const auto &Macro) { return Macro.first->isFromAST(); });
953         !FilteredMacros.empty()) {
954       Out << "   Macro Definitions:\n";
955       for (/*<IdentifierInfo *, MacroState> pair*/ const auto &Macro :
956            FilteredMacros)
957         Out << "     " << Macro.first->getName() << "\n";
958     }
959 
960     // Now let's print out any modules we did not see as part of the Primary.
961     for (const auto &SM : SubModMap) {
962       if (!SM.second.Seen && SM.second.Mod) {
963         Out << "  " << ModuleKindName(SM.second.Kind) << " '" << SM.first
964             << "' at index #" << SM.second.Idx
965             << " has no direct reference in the Primary\n";
966       }
967     }
968     Out << "  ====== ======\n";
969   }
970 
971   // The reminder of the output is produced from the listener as the AST
972   // FileCcontrolBlock is (re-)parsed.
973   ASTReader::readASTFileControlBlock(
974       getCurrentFile(), FileMgr, CI.getModuleCache(),
975       CI.getPCHContainerReader(),
976       /*FindModuleFileExtensions=*/true, Listener,
977       HSOpts.ModulesValidateDiagnosticOptions);
978 }
979 
980 //===----------------------------------------------------------------------===//
981 // Preprocessor Actions
982 //===----------------------------------------------------------------------===//
983 
984 void DumpRawTokensAction::ExecuteAction() {
985   Preprocessor &PP = getCompilerInstance().getPreprocessor();
986   SourceManager &SM = PP.getSourceManager();
987 
988   // Start lexing the specified input file.
989   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
990   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
991   RawLex.SetKeepWhitespaceMode(true);
992 
993   Token RawTok;
994   RawLex.LexFromRawLexer(RawTok);
995   while (RawTok.isNot(tok::eof)) {
996     PP.DumpToken(RawTok, true);
997     llvm::errs() << "\n";
998     RawLex.LexFromRawLexer(RawTok);
999   }
1000 }
1001 
1002 void DumpTokensAction::ExecuteAction() {
1003   Preprocessor &PP = getCompilerInstance().getPreprocessor();
1004   // Start preprocessing the specified input file.
1005   Token Tok;
1006   PP.EnterMainSourceFile();
1007   do {
1008     PP.Lex(Tok);
1009     PP.DumpToken(Tok, true);
1010     llvm::errs() << "\n";
1011   } while (Tok.isNot(tok::eof));
1012 }
1013 
1014 void PreprocessOnlyAction::ExecuteAction() {
1015   Preprocessor &PP = getCompilerInstance().getPreprocessor();
1016 
1017   // Ignore unknown pragmas.
1018   PP.IgnorePragmas();
1019 
1020   Token Tok;
1021   // Start parsing the specified input file.
1022   PP.EnterMainSourceFile();
1023   do {
1024     PP.Lex(Tok);
1025   } while (Tok.isNot(tok::eof));
1026 }
1027 
1028 void PrintPreprocessedAction::ExecuteAction() {
1029   CompilerInstance &CI = getCompilerInstance();
1030   // Output file may need to be set to 'Binary', to avoid converting Unix style
1031   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>) on Windows.
1032   //
1033   // Look to see what type of line endings the file uses. If there's a
1034   // CRLF, then we won't open the file up in binary mode. If there is
1035   // just an LF or CR, then we will open the file up in binary mode.
1036   // In this fashion, the output format should match the input format, unless
1037   // the input format has inconsistent line endings.
1038   //
1039   // This should be a relatively fast operation since most files won't have
1040   // all of their source code on a single line. However, that is still a
1041   // concern, so if we scan for too long, we'll just assume the file should
1042   // be opened in binary mode.
1043 
1044   bool BinaryMode = false;
1045   if (llvm::Triple(LLVM_HOST_TRIPLE).isOSWindows()) {
1046     BinaryMode = true;
1047     const SourceManager &SM = CI.getSourceManager();
1048     if (std::optional<llvm::MemoryBufferRef> Buffer =
1049             SM.getBufferOrNone(SM.getMainFileID())) {
1050       const char *cur = Buffer->getBufferStart();
1051       const char *end = Buffer->getBufferEnd();
1052       const char *next = (cur != end) ? cur + 1 : end;
1053 
1054       // Limit ourselves to only scanning 256 characters into the source
1055       // file.  This is mostly a check in case the file has no
1056       // newlines whatsoever.
1057       if (end - cur > 256)
1058         end = cur + 256;
1059 
1060       while (next < end) {
1061         if (*cur == 0x0D) {  // CR
1062           if (*next == 0x0A) // CRLF
1063             BinaryMode = false;
1064 
1065           break;
1066         } else if (*cur == 0x0A) // LF
1067           break;
1068 
1069         ++cur;
1070         ++next;
1071       }
1072     }
1073   }
1074 
1075   std::unique_ptr<raw_ostream> OS =
1076       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
1077   if (!OS) return;
1078 
1079   // If we're preprocessing a module map, start by dumping the contents of the
1080   // module itself before switching to the input buffer.
1081   auto &Input = getCurrentInput();
1082   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
1083     if (Input.isFile()) {
1084       (*OS) << "# 1 \"";
1085       OS->write_escaped(Input.getFile());
1086       (*OS) << "\"\n";
1087     }
1088     getCurrentModule()->print(*OS);
1089     (*OS) << "#pragma clang module contents\n";
1090   }
1091 
1092   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
1093                            CI.getPreprocessorOutputOpts());
1094 }
1095 
1096 void PrintPreambleAction::ExecuteAction() {
1097   switch (getCurrentFileKind().getLanguage()) {
1098   case Language::C:
1099   case Language::CXX:
1100   case Language::ObjC:
1101   case Language::ObjCXX:
1102   case Language::OpenCL:
1103   case Language::OpenCLCXX:
1104   case Language::CUDA:
1105   case Language::HIP:
1106   case Language::HLSL:
1107   case Language::CIR:
1108     break;
1109 
1110   case Language::Unknown:
1111   case Language::Asm:
1112   case Language::LLVM_IR:
1113   case Language::RenderScript:
1114     // We can't do anything with these.
1115     return;
1116   }
1117 
1118   // We don't expect to find any #include directives in a preprocessed input.
1119   if (getCurrentFileKind().isPreprocessed())
1120     return;
1121 
1122   CompilerInstance &CI = getCompilerInstance();
1123   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
1124   if (Buffer) {
1125     unsigned Preamble =
1126         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
1127     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
1128   }
1129 }
1130 
1131 void DumpCompilerOptionsAction::ExecuteAction() {
1132   CompilerInstance &CI = getCompilerInstance();
1133   std::unique_ptr<raw_ostream> OSP =
1134       CI.createDefaultOutputFile(false, getCurrentFile());
1135   if (!OSP)
1136     return;
1137 
1138   raw_ostream &OS = *OSP;
1139   const Preprocessor &PP = CI.getPreprocessor();
1140   const LangOptions &LangOpts = PP.getLangOpts();
1141 
1142   // FIXME: Rather than manually format the JSON (which is awkward due to
1143   // needing to remove trailing commas), this should make use of a JSON library.
1144   // FIXME: Instead of printing enums as an integral value and specifying the
1145   // type as a separate field, use introspection to print the enumerator.
1146 
1147   OS << "{\n";
1148   OS << "\n\"features\" : [\n";
1149   {
1150     llvm::SmallString<128> Str;
1151 #define FEATURE(Name, Predicate)                                               \
1152   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1153       .toVector(Str);
1154 #include "clang/Basic/Features.def"
1155 #undef FEATURE
1156     // Remove the newline and comma from the last entry to ensure this remains
1157     // valid JSON.
1158     OS << Str.substr(0, Str.size() - 2);
1159   }
1160   OS << "\n],\n";
1161 
1162   OS << "\n\"extensions\" : [\n";
1163   {
1164     llvm::SmallString<128> Str;
1165 #define EXTENSION(Name, Predicate)                                             \
1166   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1167       .toVector(Str);
1168 #include "clang/Basic/Features.def"
1169 #undef EXTENSION
1170     // Remove the newline and comma from the last entry to ensure this remains
1171     // valid JSON.
1172     OS << Str.substr(0, Str.size() - 2);
1173   }
1174   OS << "\n]\n";
1175 
1176   OS << "}";
1177 }
1178 
1179 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
1180   CompilerInstance &CI = getCompilerInstance();
1181   SourceManager &SM = CI.getPreprocessor().getSourceManager();
1182   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
1183 
1184   llvm::SmallVector<dependency_directives_scan::Token, 16> Tokens;
1185   llvm::SmallVector<dependency_directives_scan::Directive, 32> Directives;
1186   if (scanSourceForDependencyDirectives(
1187           FromFile.getBuffer(), Tokens, Directives, &CI.getDiagnostics(),
1188           SM.getLocForStartOfFile(SM.getMainFileID()))) {
1189     assert(CI.getDiagnostics().hasErrorOccurred() &&
1190            "no errors reported for failure");
1191 
1192     // Preprocess the source when verifying the diagnostics to capture the
1193     // 'expected' comments.
1194     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
1195       // Make sure we don't emit new diagnostics!
1196       CI.getDiagnostics().setSuppressAllDiagnostics(true);
1197       Preprocessor &PP = getCompilerInstance().getPreprocessor();
1198       PP.EnterMainSourceFile();
1199       Token Tok;
1200       do {
1201         PP.Lex(Tok);
1202       } while (Tok.isNot(tok::eof));
1203     }
1204     return;
1205   }
1206   printDependencyDirectivesAsSource(FromFile.getBuffer(), Directives,
1207                                     llvm::outs());
1208 }
1209 
1210 void GetDependenciesByModuleNameAction::ExecuteAction() {
1211   CompilerInstance &CI = getCompilerInstance();
1212   Preprocessor &PP = CI.getPreprocessor();
1213   SourceManager &SM = PP.getSourceManager();
1214   FileID MainFileID = SM.getMainFileID();
1215   SourceLocation FileStart = SM.getLocForStartOfFile(MainFileID);
1216   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1217   IdentifierInfo *ModuleID = PP.getIdentifierInfo(ModuleName);
1218   Path.push_back(std::make_pair(ModuleID, FileStart));
1219   auto ModResult = CI.loadModule(FileStart, Path, Module::Hidden, false);
1220   PPCallbacks *CB = PP.getPPCallbacks();
1221   CB->moduleImport(SourceLocation(), Path, ModResult);
1222 }
1223