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