xref: /freebsd/contrib/llvm-project/clang/lib/Frontend/FrontendActions.cpp (revision b64c5a0ace59af62eff52bfe110a521dc73c937b) 
1 //===--- FrontendActions.cpp ----------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "clang/Frontend/FrontendActions.h"
10 #include "clang/AST/ASTConsumer.h"
11 #include "clang/AST/Decl.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Basic/LangStandard.h"
14 #include "clang/Basic/Module.h"
15 #include "clang/Basic/TargetInfo.h"
16 #include "clang/Frontend/ASTConsumers.h"
17 #include "clang/Frontend/CompilerInstance.h"
18 #include "clang/Frontend/FrontendDiagnostic.h"
19 #include "clang/Frontend/MultiplexConsumer.h"
20 #include "clang/Frontend/Utils.h"
21 #include "clang/Lex/DependencyDirectivesScanner.h"
22 #include "clang/Lex/HeaderSearch.h"
23 #include "clang/Lex/Preprocessor.h"
24 #include "clang/Lex/PreprocessorOptions.h"
25 #include "clang/Sema/TemplateInstCallback.h"
26 #include "clang/Serialization/ASTReader.h"
27 #include "clang/Serialization/ASTWriter.h"
28 #include "clang/Serialization/ModuleFile.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/FileSystem.h"
31 #include "llvm/Support/MemoryBuffer.h"
32 #include "llvm/Support/Path.h"
33 #include "llvm/Support/YAMLTraits.h"
34 #include "llvm/Support/raw_ostream.h"
35 #include <memory>
36 #include <optional>
37 #include <system_error>
38 
39 using namespace clang;
40 
41 namespace {
42 CodeCompleteConsumer *GetCodeCompletionConsumer(CompilerInstance &CI) {
43   return CI.hasCodeCompletionConsumer() ? &CI.getCodeCompletionConsumer()
44                                         : nullptr;
45 }
46 
47 void EnsureSemaIsCreated(CompilerInstance &CI, FrontendAction &Action) {
48   if (Action.hasCodeCompletionSupport() &&
49       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
50     CI.createCodeCompletionConsumer();
51 
52   if (!CI.hasSema())
53     CI.createSema(Action.getTranslationUnitKind(),
54                   GetCodeCompletionConsumer(CI));
55 }
56 } // namespace
57 
58 //===----------------------------------------------------------------------===//
59 // Custom Actions
60 //===----------------------------------------------------------------------===//
61 
62 std::unique_ptr<ASTConsumer>
63 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
64   return std::make_unique<ASTConsumer>();
65 }
66 
67 void InitOnlyAction::ExecuteAction() {
68 }
69 
70 // Basically PreprocessOnlyAction::ExecuteAction.
71 void ReadPCHAndPreprocessAction::ExecuteAction() {
72   Preprocessor &PP = getCompilerInstance().getPreprocessor();
73 
74   // Ignore unknown pragmas.
75   PP.IgnorePragmas();
76 
77   Token Tok;
78   // Start parsing the specified input file.
79   PP.EnterMainSourceFile();
80   do {
81     PP.Lex(Tok);
82   } while (Tok.isNot(tok::eof));
83 }
84 
85 std::unique_ptr<ASTConsumer>
86 ReadPCHAndPreprocessAction::CreateASTConsumer(CompilerInstance &CI,
87                                               StringRef InFile) {
88   return std::make_unique<ASTConsumer>();
89 }
90 
91 //===----------------------------------------------------------------------===//
92 // AST Consumer Actions
93 //===----------------------------------------------------------------------===//
94 
95 std::unique_ptr<ASTConsumer>
96 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
97   if (std::unique_ptr<raw_ostream> OS =
98           CI.createDefaultOutputFile(false, InFile))
99     return CreateASTPrinter(std::move(OS), CI.getFrontendOpts().ASTDumpFilter);
100   return nullptr;
101 }
102 
103 std::unique_ptr<ASTConsumer>
104 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
105   const FrontendOptions &Opts = CI.getFrontendOpts();
106   return CreateASTDumper(nullptr /*Dump to stdout.*/, Opts.ASTDumpFilter,
107                          Opts.ASTDumpDecls, Opts.ASTDumpAll,
108                          Opts.ASTDumpLookups, Opts.ASTDumpDeclTypes,
109                          Opts.ASTDumpFormat);
110 }
111 
112 std::unique_ptr<ASTConsumer>
113 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
114   return CreateASTDeclNodeLister();
115 }
116 
117 std::unique_ptr<ASTConsumer>
118 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
119   return CreateASTViewer();
120 }
121 
122 std::unique_ptr<ASTConsumer>
123 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
124   std::string Sysroot;
125   if (!ComputeASTConsumerArguments(CI, /*ref*/ Sysroot))
126     return nullptr;
127 
128   std::string OutputFile;
129   std::unique_ptr<raw_pwrite_stream> OS =
130       CreateOutputFile(CI, InFile, /*ref*/ OutputFile);
131   if (!OS)
132     return nullptr;
133 
134   if (!CI.getFrontendOpts().RelocatablePCH)
135     Sysroot.clear();
136 
137   const auto &FrontendOpts = CI.getFrontendOpts();
138   auto Buffer = std::make_shared<PCHBuffer>();
139   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
140   Consumers.push_back(std::make_unique<PCHGenerator>(
141       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
142       FrontendOpts.ModuleFileExtensions,
143       CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
144       FrontendOpts.IncludeTimestamps, FrontendOpts.BuildingImplicitModule,
145       +CI.getLangOpts().CacheGeneratedPCH));
146   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
147       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
148 
149   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
150 }
151 
152 bool GeneratePCHAction::ComputeASTConsumerArguments(CompilerInstance &CI,
153                                                     std::string &Sysroot) {
154   Sysroot = CI.getHeaderSearchOpts().Sysroot;
155   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
156     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
157     return false;
158   }
159 
160   return true;
161 }
162 
163 std::unique_ptr<llvm::raw_pwrite_stream>
164 GeneratePCHAction::CreateOutputFile(CompilerInstance &CI, StringRef InFile,
165                                     std::string &OutputFile) {
166   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
167   std::unique_ptr<raw_pwrite_stream> OS = CI.createDefaultOutputFile(
168       /*Binary=*/true, InFile, /*Extension=*/"", /*RemoveFileOnSignal=*/false);
169   if (!OS)
170     return nullptr;
171 
172   OutputFile = CI.getFrontendOpts().OutputFile;
173   return OS;
174 }
175 
176 bool GeneratePCHAction::shouldEraseOutputFiles() {
177   if (getCompilerInstance().getPreprocessorOpts().AllowPCHWithCompilerErrors)
178     return false;
179   return ASTFrontendAction::shouldEraseOutputFiles();
180 }
181 
182 bool GeneratePCHAction::BeginSourceFileAction(CompilerInstance &CI) {
183   CI.getLangOpts().CompilingPCH = true;
184   return true;
185 }
186 
187 std::vector<std::unique_ptr<ASTConsumer>>
188 GenerateModuleAction::CreateMultiplexConsumer(CompilerInstance &CI,
189                                               StringRef InFile) {
190   std::unique_ptr<raw_pwrite_stream> OS = CreateOutputFile(CI, InFile);
191   if (!OS)
192     return {};
193 
194   std::string OutputFile = CI.getFrontendOpts().OutputFile;
195   std::string Sysroot;
196 
197   auto Buffer = std::make_shared<PCHBuffer>();
198   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
199 
200   Consumers.push_back(std::make_unique<PCHGenerator>(
201       CI.getPreprocessor(), CI.getModuleCache(), OutputFile, Sysroot, Buffer,
202       CI.getFrontendOpts().ModuleFileExtensions,
203       /*AllowASTWithErrors=*/
204       +CI.getFrontendOpts().AllowPCMWithCompilerErrors,
205       /*IncludeTimestamps=*/
206       +CI.getFrontendOpts().BuildingImplicitModule &&
207           +CI.getFrontendOpts().IncludeTimestamps,
208       /*BuildingImplicitModule=*/+CI.getFrontendOpts().BuildingImplicitModule,
209       /*ShouldCacheASTInMemory=*/
210       +CI.getFrontendOpts().BuildingImplicitModule));
211   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
212       CI, std::string(InFile), OutputFile, std::move(OS), Buffer));
213   return Consumers;
214 }
215 
216 std::unique_ptr<ASTConsumer>
217 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
218                                         StringRef InFile) {
219   std::vector<std::unique_ptr<ASTConsumer>> Consumers =
220       CreateMultiplexConsumer(CI, InFile);
221   if (Consumers.empty())
222     return nullptr;
223 
224   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
225 }
226 
227 bool GenerateModuleAction::shouldEraseOutputFiles() {
228   return !getCompilerInstance().getFrontendOpts().AllowPCMWithCompilerErrors &&
229          ASTFrontendAction::shouldEraseOutputFiles();
230 }
231 
232 bool GenerateModuleFromModuleMapAction::BeginSourceFileAction(
233     CompilerInstance &CI) {
234   if (!CI.getLangOpts().Modules) {
235     CI.getDiagnostics().Report(diag::err_module_build_requires_fmodules);
236     return false;
237   }
238 
239   return GenerateModuleAction::BeginSourceFileAction(CI);
240 }
241 
242 std::unique_ptr<raw_pwrite_stream>
243 GenerateModuleFromModuleMapAction::CreateOutputFile(CompilerInstance &CI,
244                                                     StringRef InFile) {
245   // If no output file was provided, figure out where this module would go
246   // in the module cache.
247   if (CI.getFrontendOpts().OutputFile.empty()) {
248     StringRef ModuleMapFile = CI.getFrontendOpts().OriginalModuleMap;
249     if (ModuleMapFile.empty())
250       ModuleMapFile = InFile;
251 
252     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
253     CI.getFrontendOpts().OutputFile =
254         HS.getCachedModuleFileName(CI.getLangOpts().CurrentModule,
255                                    ModuleMapFile);
256   }
257 
258   // Because this is exposed via libclang we must disable RemoveFileOnSignal.
259   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, /*Extension=*/"",
260                                     /*RemoveFileOnSignal=*/false,
261                                     /*CreateMissingDirectories=*/true,
262                                     /*ForceUseTemporary=*/true);
263 }
264 
265 bool GenerateModuleInterfaceAction::BeginSourceFileAction(
266     CompilerInstance &CI) {
267   CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleInterface);
268 
269   return GenerateModuleAction::BeginSourceFileAction(CI);
270 }
271 
272 std::unique_ptr<ASTConsumer>
273 GenerateModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
274                                                  StringRef InFile) {
275   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
276 
277   if (CI.getFrontendOpts().GenReducedBMI &&
278       !CI.getFrontendOpts().ModuleOutputPath.empty()) {
279     Consumers.push_back(std::make_unique<ReducedBMIGenerator>(
280         CI.getPreprocessor(), CI.getModuleCache(),
281         CI.getFrontendOpts().ModuleOutputPath));
282   }
283 
284   Consumers.push_back(std::make_unique<CXX20ModulesGenerator>(
285       CI.getPreprocessor(), CI.getModuleCache(),
286       CI.getFrontendOpts().OutputFile));
287 
288   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
289 }
290 
291 std::unique_ptr<raw_pwrite_stream>
292 GenerateModuleInterfaceAction::CreateOutputFile(CompilerInstance &CI,
293                                                 StringRef InFile) {
294   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
295 }
296 
297 std::unique_ptr<ASTConsumer>
298 GenerateReducedModuleInterfaceAction::CreateASTConsumer(CompilerInstance &CI,
299                                                         StringRef InFile) {
300   return std::make_unique<ReducedBMIGenerator>(CI.getPreprocessor(),
301                                                CI.getModuleCache(),
302                                                CI.getFrontendOpts().OutputFile);
303 }
304 
305 bool GenerateHeaderUnitAction::BeginSourceFileAction(CompilerInstance &CI) {
306   if (!CI.getLangOpts().CPlusPlusModules) {
307     CI.getDiagnostics().Report(diag::err_module_interface_requires_cpp_modules);
308     return false;
309   }
310   CI.getLangOpts().setCompilingModule(LangOptions::CMK_HeaderUnit);
311   return GenerateModuleAction::BeginSourceFileAction(CI);
312 }
313 
314 std::unique_ptr<raw_pwrite_stream>
315 GenerateHeaderUnitAction::CreateOutputFile(CompilerInstance &CI,
316                                            StringRef InFile) {
317   return CI.createDefaultOutputFile(/*Binary=*/true, InFile, "pcm");
318 }
319 
320 SyntaxOnlyAction::~SyntaxOnlyAction() {
321 }
322 
323 std::unique_ptr<ASTConsumer>
324 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
325   return std::make_unique<ASTConsumer>();
326 }
327 
328 std::unique_ptr<ASTConsumer>
329 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
330                                         StringRef InFile) {
331   return std::make_unique<ASTConsumer>();
332 }
333 
334 std::unique_ptr<ASTConsumer>
335 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
336   return std::make_unique<ASTConsumer>();
337 }
338 
339 void VerifyPCHAction::ExecuteAction() {
340   CompilerInstance &CI = getCompilerInstance();
341   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
342   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
343   std::unique_ptr<ASTReader> Reader(new ASTReader(
344       CI.getPreprocessor(), CI.getModuleCache(), &CI.getASTContext(),
345       CI.getPCHContainerReader(), CI.getFrontendOpts().ModuleFileExtensions,
346       Sysroot.empty() ? "" : Sysroot.c_str(),
347       DisableValidationForModuleKind::None,
348       /*AllowASTWithCompilerErrors*/ false,
349       /*AllowConfigurationMismatch*/ true,
350       /*ValidateSystemInputs*/ true));
351 
352   Reader->ReadAST(getCurrentFile(),
353                   Preamble ? serialization::MK_Preamble
354                            : serialization::MK_PCH,
355                   SourceLocation(),
356                   ASTReader::ARR_ConfigurationMismatch);
357 }
358 
359 namespace {
360 struct TemplightEntry {
361   std::string Name;
362   std::string Kind;
363   std::string Event;
364   std::string DefinitionLocation;
365   std::string PointOfInstantiation;
366 };
367 } // namespace
368 
369 namespace llvm {
370 namespace yaml {
371 template <> struct MappingTraits<TemplightEntry> {
372   static void mapping(IO &io, TemplightEntry &fields) {
373     io.mapRequired("name", fields.Name);
374     io.mapRequired("kind", fields.Kind);
375     io.mapRequired("event", fields.Event);
376     io.mapRequired("orig", fields.DefinitionLocation);
377     io.mapRequired("poi", fields.PointOfInstantiation);
378   }
379 };
380 } // namespace yaml
381 } // namespace llvm
382 
383 namespace {
384 class DefaultTemplateInstCallback : public TemplateInstantiationCallback {
385   using CodeSynthesisContext = Sema::CodeSynthesisContext;
386 
387 public:
388   void initialize(const Sema &) override {}
389 
390   void finalize(const Sema &) override {}
391 
392   void atTemplateBegin(const Sema &TheSema,
393                        const CodeSynthesisContext &Inst) override {
394     displayTemplightEntry<true>(llvm::outs(), TheSema, Inst);
395   }
396 
397   void atTemplateEnd(const Sema &TheSema,
398                      const CodeSynthesisContext &Inst) override {
399     displayTemplightEntry<false>(llvm::outs(), TheSema, Inst);
400   }
401 
402 private:
403   static std::string toString(CodeSynthesisContext::SynthesisKind Kind) {
404     switch (Kind) {
405     case CodeSynthesisContext::TemplateInstantiation:
406       return "TemplateInstantiation";
407     case CodeSynthesisContext::DefaultTemplateArgumentInstantiation:
408       return "DefaultTemplateArgumentInstantiation";
409     case CodeSynthesisContext::DefaultFunctionArgumentInstantiation:
410       return "DefaultFunctionArgumentInstantiation";
411     case CodeSynthesisContext::ExplicitTemplateArgumentSubstitution:
412       return "ExplicitTemplateArgumentSubstitution";
413     case CodeSynthesisContext::DeducedTemplateArgumentSubstitution:
414       return "DeducedTemplateArgumentSubstitution";
415     case CodeSynthesisContext::LambdaExpressionSubstitution:
416       return "LambdaExpressionSubstitution";
417     case CodeSynthesisContext::PriorTemplateArgumentSubstitution:
418       return "PriorTemplateArgumentSubstitution";
419     case CodeSynthesisContext::DefaultTemplateArgumentChecking:
420       return "DefaultTemplateArgumentChecking";
421     case CodeSynthesisContext::ExceptionSpecEvaluation:
422       return "ExceptionSpecEvaluation";
423     case CodeSynthesisContext::ExceptionSpecInstantiation:
424       return "ExceptionSpecInstantiation";
425     case CodeSynthesisContext::DeclaringSpecialMember:
426       return "DeclaringSpecialMember";
427     case CodeSynthesisContext::DeclaringImplicitEqualityComparison:
428       return "DeclaringImplicitEqualityComparison";
429     case CodeSynthesisContext::DefiningSynthesizedFunction:
430       return "DefiningSynthesizedFunction";
431     case CodeSynthesisContext::RewritingOperatorAsSpaceship:
432       return "RewritingOperatorAsSpaceship";
433     case CodeSynthesisContext::Memoization:
434       return "Memoization";
435     case CodeSynthesisContext::ConstraintsCheck:
436       return "ConstraintsCheck";
437     case CodeSynthesisContext::ConstraintSubstitution:
438       return "ConstraintSubstitution";
439     case CodeSynthesisContext::ConstraintNormalization:
440       return "ConstraintNormalization";
441     case CodeSynthesisContext::RequirementParameterInstantiation:
442       return "RequirementParameterInstantiation";
443     case CodeSynthesisContext::ParameterMappingSubstitution:
444       return "ParameterMappingSubstitution";
445     case CodeSynthesisContext::RequirementInstantiation:
446       return "RequirementInstantiation";
447     case CodeSynthesisContext::NestedRequirementConstraintsCheck:
448       return "NestedRequirementConstraintsCheck";
449     case CodeSynthesisContext::InitializingStructuredBinding:
450       return "InitializingStructuredBinding";
451     case CodeSynthesisContext::MarkingClassDllexported:
452       return "MarkingClassDllexported";
453     case CodeSynthesisContext::BuildingBuiltinDumpStructCall:
454       return "BuildingBuiltinDumpStructCall";
455     case CodeSynthesisContext::BuildingDeductionGuides:
456       return "BuildingDeductionGuides";
457     case CodeSynthesisContext::TypeAliasTemplateInstantiation:
458       return "TypeAliasTemplateInstantiation";
459     }
460     return "";
461   }
462 
463   template <bool BeginInstantiation>
464   static void displayTemplightEntry(llvm::raw_ostream &Out, const Sema &TheSema,
465                                     const CodeSynthesisContext &Inst) {
466     std::string YAML;
467     {
468       llvm::raw_string_ostream OS(YAML);
469       llvm::yaml::Output YO(OS);
470       TemplightEntry Entry =
471           getTemplightEntry<BeginInstantiation>(TheSema, Inst);
472       llvm::yaml::EmptyContext Context;
473       llvm::yaml::yamlize(YO, Entry, true, Context);
474     }
475     Out << "---" << YAML << "\n";
476   }
477 
478   static void printEntryName(const Sema &TheSema, const Decl *Entity,
479                              llvm::raw_string_ostream &OS) {
480     auto *NamedTemplate = cast<NamedDecl>(Entity);
481 
482     PrintingPolicy Policy = TheSema.Context.getPrintingPolicy();
483     // FIXME: Also ask for FullyQualifiedNames?
484     Policy.SuppressDefaultTemplateArgs = false;
485     NamedTemplate->getNameForDiagnostic(OS, Policy, true);
486 
487     if (!OS.str().empty())
488       return;
489 
490     Decl *Ctx = Decl::castFromDeclContext(NamedTemplate->getDeclContext());
491     NamedDecl *NamedCtx = dyn_cast_or_null<NamedDecl>(Ctx);
492 
493     if (const auto *Decl = dyn_cast<TagDecl>(NamedTemplate)) {
494       if (const auto *R = dyn_cast<RecordDecl>(Decl)) {
495         if (R->isLambda()) {
496           OS << "lambda at ";
497           Decl->getLocation().print(OS, TheSema.getSourceManager());
498           return;
499         }
500       }
501       OS << "unnamed " << Decl->getKindName();
502       return;
503     }
504 
505     assert(NamedCtx && "NamedCtx cannot be null");
506 
507     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
508       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
509          << " ";
510       if (Decl->getFunctionScopeDepth() > 0)
511         OS << "(at depth " << Decl->getFunctionScopeDepth() << ") ";
512       OS << "of ";
513       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
514       return;
515     }
516 
517     if (const auto *Decl = dyn_cast<TemplateTypeParmDecl>(NamedTemplate)) {
518       if (const Type *Ty = Decl->getTypeForDecl()) {
519         if (const auto *TTPT = dyn_cast_or_null<TemplateTypeParmType>(Ty)) {
520           OS << "unnamed template type parameter " << TTPT->getIndex() << " ";
521           if (TTPT->getDepth() > 0)
522             OS << "(at depth " << TTPT->getDepth() << ") ";
523           OS << "of ";
524           NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
525           return;
526         }
527       }
528     }
529 
530     if (const auto *Decl = dyn_cast<NonTypeTemplateParmDecl>(NamedTemplate)) {
531       OS << "unnamed template non-type parameter " << Decl->getIndex() << " ";
532       if (Decl->getDepth() > 0)
533         OS << "(at depth " << Decl->getDepth() << ") ";
534       OS << "of ";
535       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
536       return;
537     }
538 
539     if (const auto *Decl = dyn_cast<TemplateTemplateParmDecl>(NamedTemplate)) {
540       OS << "unnamed template template parameter " << Decl->getIndex() << " ";
541       if (Decl->getDepth() > 0)
542         OS << "(at depth " << Decl->getDepth() << ") ";
543       OS << "of ";
544       NamedCtx->getNameForDiagnostic(OS, TheSema.getLangOpts(), true);
545       return;
546     }
547 
548     llvm_unreachable("Failed to retrieve a name for this entry!");
549     OS << "unnamed identifier";
550   }
551 
552   template <bool BeginInstantiation>
553   static TemplightEntry getTemplightEntry(const Sema &TheSema,
554                                           const CodeSynthesisContext &Inst) {
555     TemplightEntry Entry;
556     Entry.Kind = toString(Inst.Kind);
557     Entry.Event = BeginInstantiation ? "Begin" : "End";
558     llvm::raw_string_ostream OS(Entry.Name);
559     printEntryName(TheSema, Inst.Entity, OS);
560     const PresumedLoc DefLoc =
561         TheSema.getSourceManager().getPresumedLoc(Inst.Entity->getLocation());
562     if (!DefLoc.isInvalid())
563       Entry.DefinitionLocation = std::string(DefLoc.getFilename()) + ":" +
564                                  std::to_string(DefLoc.getLine()) + ":" +
565                                  std::to_string(DefLoc.getColumn());
566     const PresumedLoc PoiLoc =
567         TheSema.getSourceManager().getPresumedLoc(Inst.PointOfInstantiation);
568     if (!PoiLoc.isInvalid()) {
569       Entry.PointOfInstantiation = std::string(PoiLoc.getFilename()) + ":" +
570                                    std::to_string(PoiLoc.getLine()) + ":" +
571                                    std::to_string(PoiLoc.getColumn());
572     }
573     return Entry;
574   }
575 };
576 } // namespace
577 
578 std::unique_ptr<ASTConsumer>
579 TemplightDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
580   return std::make_unique<ASTConsumer>();
581 }
582 
583 void TemplightDumpAction::ExecuteAction() {
584   CompilerInstance &CI = getCompilerInstance();
585 
586   // This part is normally done by ASTFrontEndAction, but needs to happen
587   // before Templight observers can be created
588   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
589   // here so the source manager would be initialized.
590   EnsureSemaIsCreated(CI, *this);
591 
592   CI.getSema().TemplateInstCallbacks.push_back(
593       std::make_unique<DefaultTemplateInstCallback>());
594   ASTFrontendAction::ExecuteAction();
595 }
596 
597 namespace {
598   /// AST reader listener that dumps module information for a module
599   /// file.
600   class DumpModuleInfoListener : public ASTReaderListener {
601     llvm::raw_ostream &Out;
602 
603   public:
604     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
605 
606 #define DUMP_BOOLEAN(Value, Text)                       \
607     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
608 
609     bool ReadFullVersionInformation(StringRef FullVersion) override {
610       Out.indent(2)
611         << "Generated by "
612         << (FullVersion == getClangFullRepositoryVersion()? "this"
613                                                           : "a different")
614         << " Clang: " << FullVersion << "\n";
615       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
616     }
617 
618     void ReadModuleName(StringRef ModuleName) override {
619       Out.indent(2) << "Module name: " << ModuleName << "\n";
620     }
621     void ReadModuleMapFile(StringRef ModuleMapPath) override {
622       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
623     }
624 
625     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
626                              bool AllowCompatibleDifferences) override {
627       Out.indent(2) << "Language options:\n";
628 #define LANGOPT(Name, Bits, Default, Description) \
629       DUMP_BOOLEAN(LangOpts.Name, Description);
630 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
631       Out.indent(4) << Description << ": "                   \
632                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
633 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
634       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
635 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
636 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
637 #include "clang/Basic/LangOptions.def"
638 
639       if (!LangOpts.ModuleFeatures.empty()) {
640         Out.indent(4) << "Module features:\n";
641         for (StringRef Feature : LangOpts.ModuleFeatures)
642           Out.indent(6) << Feature << "\n";
643       }
644 
645       return false;
646     }
647 
648     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
649                            bool AllowCompatibleDifferences) override {
650       Out.indent(2) << "Target options:\n";
651       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
652       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
653       Out.indent(4) << "  TuneCPU: " << TargetOpts.TuneCPU << "\n";
654       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
655 
656       if (!TargetOpts.FeaturesAsWritten.empty()) {
657         Out.indent(4) << "Target features:\n";
658         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
659              I != N; ++I) {
660           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
661         }
662       }
663 
664       return false;
665     }
666 
667     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
668                                bool Complain) override {
669       Out.indent(2) << "Diagnostic options:\n";
670 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
671 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
672       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
673 #define VALUE_DIAGOPT(Name, Bits, Default) \
674       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
675 #include "clang/Basic/DiagnosticOptions.def"
676 
677       Out.indent(4) << "Diagnostic flags:\n";
678       for (const std::string &Warning : DiagOpts->Warnings)
679         Out.indent(6) << "-W" << Warning << "\n";
680       for (const std::string &Remark : DiagOpts->Remarks)
681         Out.indent(6) << "-R" << Remark << "\n";
682 
683       return false;
684     }
685 
686     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
687                                  StringRef SpecificModuleCachePath,
688                                  bool Complain) override {
689       Out.indent(2) << "Header search options:\n";
690       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
691       Out.indent(4) << "Resource dir [ -resource-dir=]: '" << HSOpts.ResourceDir << "'\n";
692       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
693       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
694                    "Use builtin include directories [-nobuiltininc]");
695       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
696                    "Use standard system include directories [-nostdinc]");
697       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
698                    "Use standard C++ include directories [-nostdinc++]");
699       DUMP_BOOLEAN(HSOpts.UseLibcxx,
700                    "Use libc++ (rather than libstdc++) [-stdlib=]");
701       return false;
702     }
703 
704     bool ReadHeaderSearchPaths(const HeaderSearchOptions &HSOpts,
705                                bool Complain) override {
706       Out.indent(2) << "Header search paths:\n";
707       Out.indent(4) << "User entries:\n";
708       for (const auto &Entry : HSOpts.UserEntries)
709         Out.indent(6) << Entry.Path << "\n";
710       Out.indent(4) << "System header prefixes:\n";
711       for (const auto &Prefix : HSOpts.SystemHeaderPrefixes)
712         Out.indent(6) << Prefix.Prefix << "\n";
713       Out.indent(4) << "VFS overlay files:\n";
714       for (const auto &Overlay : HSOpts.VFSOverlayFiles)
715         Out.indent(6) << Overlay << "\n";
716       return false;
717     }
718 
719     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
720                                  bool ReadMacros, bool Complain,
721                                  std::string &SuggestedPredefines) override {
722       Out.indent(2) << "Preprocessor options:\n";
723       DUMP_BOOLEAN(PPOpts.UsePredefines,
724                    "Uses compiler/target-specific predefines [-undef]");
725       DUMP_BOOLEAN(PPOpts.DetailedRecord,
726                    "Uses detailed preprocessing record (for indexing)");
727 
728       if (ReadMacros) {
729         Out.indent(4) << "Predefined macros:\n";
730       }
731 
732       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
733              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
734            I != IEnd; ++I) {
735         Out.indent(6);
736         if (I->second)
737           Out << "-U";
738         else
739           Out << "-D";
740         Out << I->first << "\n";
741       }
742       return false;
743     }
744 
745     /// Indicates that a particular module file extension has been read.
746     void readModuleFileExtension(
747            const ModuleFileExtensionMetadata &Metadata) override {
748       Out.indent(2) << "Module file extension '"
749                     << Metadata.BlockName << "' " << Metadata.MajorVersion
750                     << "." << Metadata.MinorVersion;
751       if (!Metadata.UserInfo.empty()) {
752         Out << ": ";
753         Out.write_escaped(Metadata.UserInfo);
754       }
755 
756       Out << "\n";
757     }
758 
759     /// Tells the \c ASTReaderListener that we want to receive the
760     /// input files of the AST file via \c visitInputFile.
761     bool needsInputFileVisitation() override { return true; }
762 
763     /// Tells the \c ASTReaderListener that we want to receive the
764     /// input files of the AST file via \c visitInputFile.
765     bool needsSystemInputFileVisitation() override { return true; }
766 
767     /// Indicates that the AST file contains particular input file.
768     ///
769     /// \returns true to continue receiving the next input file, false to stop.
770     bool visitInputFile(StringRef Filename, bool isSystem,
771                         bool isOverridden, bool isExplicitModule) override {
772 
773       Out.indent(2) << "Input file: " << Filename;
774 
775       if (isSystem || isOverridden || isExplicitModule) {
776         Out << " [";
777         if (isSystem) {
778           Out << "System";
779           if (isOverridden || isExplicitModule)
780             Out << ", ";
781         }
782         if (isOverridden) {
783           Out << "Overridden";
784           if (isExplicitModule)
785             Out << ", ";
786         }
787         if (isExplicitModule)
788           Out << "ExplicitModule";
789 
790         Out << "]";
791       }
792 
793       Out << "\n";
794 
795       return true;
796     }
797 
798     /// Returns true if this \c ASTReaderListener wants to receive the
799     /// imports of the AST file via \c visitImport, false otherwise.
800     bool needsImportVisitation() const override { return true; }
801 
802     /// If needsImportVisitation returns \c true, this is called for each
803     /// AST file imported by this AST file.
804     void visitImport(StringRef ModuleName, StringRef Filename) override {
805       Out.indent(2) << "Imports module '" << ModuleName
806                     << "': " << Filename.str() << "\n";
807     }
808 #undef DUMP_BOOLEAN
809   };
810 }
811 
812 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
813   // The Object file reader also supports raw ast files and there is no point in
814   // being strict about the module file format in -module-file-info mode.
815   CI.getHeaderSearchOpts().ModuleFormat = "obj";
816   return true;
817 }
818 
819 static StringRef ModuleKindName(Module::ModuleKind MK) {
820   switch (MK) {
821   case Module::ModuleMapModule:
822     return "Module Map Module";
823   case Module::ModuleInterfaceUnit:
824     return "Interface Unit";
825   case Module::ModuleImplementationUnit:
826     return "Implementation Unit";
827   case Module::ModulePartitionInterface:
828     return "Partition Interface";
829   case Module::ModulePartitionImplementation:
830     return "Partition Implementation";
831   case Module::ModuleHeaderUnit:
832     return "Header Unit";
833   case Module::ExplicitGlobalModuleFragment:
834     return "Global Module Fragment";
835   case Module::ImplicitGlobalModuleFragment:
836     return "Implicit Module Fragment";
837   case Module::PrivateModuleFragment:
838     return "Private Module Fragment";
839   }
840   llvm_unreachable("unknown module kind!");
841 }
842 
843 void DumpModuleInfoAction::ExecuteAction() {
844   CompilerInstance &CI = getCompilerInstance();
845 
846   // Don't process files of type other than module to avoid crash
847   if (!isCurrentFileAST()) {
848     CI.getDiagnostics().Report(diag::err_file_is_not_module)
849         << getCurrentFile();
850     return;
851   }
852 
853   // Set up the output file.
854   StringRef OutputFileName = CI.getFrontendOpts().OutputFile;
855   if (!OutputFileName.empty() && OutputFileName != "-") {
856     std::error_code EC;
857     OutputStream.reset(new llvm::raw_fd_ostream(
858         OutputFileName.str(), EC, llvm::sys::fs::OF_TextWithCRLF));
859   }
860   llvm::raw_ostream &Out = OutputStream ? *OutputStream : llvm::outs();
861 
862   Out << "Information for module file '" << getCurrentFile() << "':\n";
863   auto &FileMgr = CI.getFileManager();
864   auto Buffer = FileMgr.getBufferForFile(getCurrentFile());
865   StringRef Magic = (*Buffer)->getMemBufferRef().getBuffer();
866   bool IsRaw = Magic.starts_with("CPCH");
867   Out << "  Module format: " << (IsRaw ? "raw" : "obj") << "\n";
868 
869   Preprocessor &PP = CI.getPreprocessor();
870   DumpModuleInfoListener Listener(Out);
871   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
872 
873   // The FrontendAction::BeginSourceFile () method loads the AST so that much
874   // of the information is already available and modules should have been
875   // loaded.
876 
877   const LangOptions &LO = getCurrentASTUnit().getLangOpts();
878   if (LO.CPlusPlusModules && !LO.CurrentModule.empty()) {
879     ASTReader *R = getCurrentASTUnit().getASTReader().get();
880     unsigned SubModuleCount = R->getTotalNumSubmodules();
881     serialization::ModuleFile &MF = R->getModuleManager().getPrimaryModule();
882     Out << "  ====== C++20 Module structure ======\n";
883 
884     if (MF.ModuleName != LO.CurrentModule)
885       Out << "  Mismatched module names : " << MF.ModuleName << " and "
886           << LO.CurrentModule << "\n";
887 
888     struct SubModInfo {
889       unsigned Idx;
890       Module *Mod;
891       Module::ModuleKind Kind;
892       std::string &Name;
893       bool Seen;
894     };
895     std::map<std::string, SubModInfo> SubModMap;
896     auto PrintSubMapEntry = [&](std::string Name, Module::ModuleKind Kind) {
897       Out << "    " << ModuleKindName(Kind) << " '" << Name << "'";
898       auto I = SubModMap.find(Name);
899       if (I == SubModMap.end())
900         Out << " was not found in the sub modules!\n";
901       else {
902         I->second.Seen = true;
903         Out << " is at index #" << I->second.Idx << "\n";
904       }
905     };
906     Module *Primary = nullptr;
907     for (unsigned Idx = 0; Idx <= SubModuleCount; ++Idx) {
908       Module *M = R->getModule(Idx);
909       if (!M)
910         continue;
911       if (M->Name == LO.CurrentModule) {
912         Primary = M;
913         Out << "  " << ModuleKindName(M->Kind) << " '" << LO.CurrentModule
914             << "' is the Primary Module at index #" << Idx << "\n";
915         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, true}});
916       } else
917         SubModMap.insert({M->Name, {Idx, M, M->Kind, M->Name, false}});
918     }
919     if (Primary) {
920       if (!Primary->submodules().empty())
921         Out << "   Sub Modules:\n";
922       for (auto *MI : Primary->submodules()) {
923         PrintSubMapEntry(MI->Name, MI->Kind);
924       }
925       if (!Primary->Imports.empty())
926         Out << "   Imports:\n";
927       for (auto *IMP : Primary->Imports) {
928         PrintSubMapEntry(IMP->Name, IMP->Kind);
929       }
930       if (!Primary->Exports.empty())
931         Out << "   Exports:\n";
932       for (unsigned MN = 0, N = Primary->Exports.size(); MN != N; ++MN) {
933         if (Module *M = Primary->Exports[MN].getPointer()) {
934           PrintSubMapEntry(M->Name, M->Kind);
935         }
936       }
937     }
938 
939     // Emit the macro definitions in the module file so that we can know how
940     // much definitions in the module file quickly.
941     // TODO: Emit the macro definition bodies completely.
942     if (auto FilteredMacros = llvm::make_filter_range(
943             R->getPreprocessor().macros(),
944             [](const auto &Macro) { return Macro.first->isFromAST(); });
945         !FilteredMacros.empty()) {
946       Out << "   Macro Definitions:\n";
947       for (/*<IdentifierInfo *, MacroState> pair*/ const auto &Macro :
948            FilteredMacros)
949         Out << "     " << Macro.first->getName() << "\n";
950     }
951 
952     // Now let's print out any modules we did not see as part of the Primary.
953     for (const auto &SM : SubModMap) {
954       if (!SM.second.Seen && SM.second.Mod) {
955         Out << "  " << ModuleKindName(SM.second.Kind) << " '" << SM.first
956             << "' at index #" << SM.second.Idx
957             << " has no direct reference in the Primary\n";
958       }
959     }
960     Out << "  ====== ======\n";
961   }
962 
963   // The reminder of the output is produced from the listener as the AST
964   // FileCcontrolBlock is (re-)parsed.
965   ASTReader::readASTFileControlBlock(
966       getCurrentFile(), FileMgr, CI.getModuleCache(),
967       CI.getPCHContainerReader(),
968       /*FindModuleFileExtensions=*/true, Listener,
969       HSOpts.ModulesValidateDiagnosticOptions);
970 }
971 
972 //===----------------------------------------------------------------------===//
973 // Preprocessor Actions
974 //===----------------------------------------------------------------------===//
975 
976 void DumpRawTokensAction::ExecuteAction() {
977   Preprocessor &PP = getCompilerInstance().getPreprocessor();
978   SourceManager &SM = PP.getSourceManager();
979 
980   // Start lexing the specified input file.
981   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
982   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
983   RawLex.SetKeepWhitespaceMode(true);
984 
985   Token RawTok;
986   RawLex.LexFromRawLexer(RawTok);
987   while (RawTok.isNot(tok::eof)) {
988     PP.DumpToken(RawTok, true);
989     llvm::errs() << "\n";
990     RawLex.LexFromRawLexer(RawTok);
991   }
992 }
993 
994 void DumpTokensAction::ExecuteAction() {
995   Preprocessor &PP = getCompilerInstance().getPreprocessor();
996   // Start preprocessing the specified input file.
997   Token Tok;
998   PP.EnterMainSourceFile();
999   do {
1000     PP.Lex(Tok);
1001     PP.DumpToken(Tok, true);
1002     llvm::errs() << "\n";
1003   } while (Tok.isNot(tok::eof));
1004 }
1005 
1006 void PreprocessOnlyAction::ExecuteAction() {
1007   Preprocessor &PP = getCompilerInstance().getPreprocessor();
1008 
1009   // Ignore unknown pragmas.
1010   PP.IgnorePragmas();
1011 
1012   Token Tok;
1013   // Start parsing the specified input file.
1014   PP.EnterMainSourceFile();
1015   do {
1016     PP.Lex(Tok);
1017   } while (Tok.isNot(tok::eof));
1018 }
1019 
1020 void PrintPreprocessedAction::ExecuteAction() {
1021   CompilerInstance &CI = getCompilerInstance();
1022   // Output file may need to be set to 'Binary', to avoid converting Unix style
1023   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>) on Windows.
1024   //
1025   // Look to see what type of line endings the file uses. If there's a
1026   // CRLF, then we won't open the file up in binary mode. If there is
1027   // just an LF or CR, then we will open the file up in binary mode.
1028   // In this fashion, the output format should match the input format, unless
1029   // the input format has inconsistent line endings.
1030   //
1031   // This should be a relatively fast operation since most files won't have
1032   // all of their source code on a single line. However, that is still a
1033   // concern, so if we scan for too long, we'll just assume the file should
1034   // be opened in binary mode.
1035 
1036   bool BinaryMode = false;
1037   if (llvm::Triple(LLVM_HOST_TRIPLE).isOSWindows()) {
1038     BinaryMode = true;
1039     const SourceManager &SM = CI.getSourceManager();
1040     if (std::optional<llvm::MemoryBufferRef> Buffer =
1041             SM.getBufferOrNone(SM.getMainFileID())) {
1042       const char *cur = Buffer->getBufferStart();
1043       const char *end = Buffer->getBufferEnd();
1044       const char *next = (cur != end) ? cur + 1 : end;
1045 
1046       // Limit ourselves to only scanning 256 characters into the source
1047       // file.  This is mostly a check in case the file has no
1048       // newlines whatsoever.
1049       if (end - cur > 256)
1050         end = cur + 256;
1051 
1052       while (next < end) {
1053         if (*cur == 0x0D) {  // CR
1054           if (*next == 0x0A) // CRLF
1055             BinaryMode = false;
1056 
1057           break;
1058         } else if (*cur == 0x0A) // LF
1059           break;
1060 
1061         ++cur;
1062         ++next;
1063       }
1064     }
1065   }
1066 
1067   std::unique_ptr<raw_ostream> OS =
1068       CI.createDefaultOutputFile(BinaryMode, getCurrentFileOrBufferName());
1069   if (!OS) return;
1070 
1071   // If we're preprocessing a module map, start by dumping the contents of the
1072   // module itself before switching to the input buffer.
1073   auto &Input = getCurrentInput();
1074   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
1075     if (Input.isFile()) {
1076       (*OS) << "# 1 \"";
1077       OS->write_escaped(Input.getFile());
1078       (*OS) << "\"\n";
1079     }
1080     getCurrentModule()->print(*OS);
1081     (*OS) << "#pragma clang module contents\n";
1082   }
1083 
1084   DoPrintPreprocessedInput(CI.getPreprocessor(), OS.get(),
1085                            CI.getPreprocessorOutputOpts());
1086 }
1087 
1088 void PrintPreambleAction::ExecuteAction() {
1089   switch (getCurrentFileKind().getLanguage()) {
1090   case Language::C:
1091   case Language::CXX:
1092   case Language::ObjC:
1093   case Language::ObjCXX:
1094   case Language::OpenCL:
1095   case Language::OpenCLCXX:
1096   case Language::CUDA:
1097   case Language::HIP:
1098   case Language::HLSL:
1099   case Language::CIR:
1100     break;
1101 
1102   case Language::Unknown:
1103   case Language::Asm:
1104   case Language::LLVM_IR:
1105   case Language::RenderScript:
1106     // We can't do anything with these.
1107     return;
1108   }
1109 
1110   // We don't expect to find any #include directives in a preprocessed input.
1111   if (getCurrentFileKind().isPreprocessed())
1112     return;
1113 
1114   CompilerInstance &CI = getCompilerInstance();
1115   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
1116   if (Buffer) {
1117     unsigned Preamble =
1118         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).Size;
1119     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
1120   }
1121 }
1122 
1123 void DumpCompilerOptionsAction::ExecuteAction() {
1124   CompilerInstance &CI = getCompilerInstance();
1125   std::unique_ptr<raw_ostream> OSP =
1126       CI.createDefaultOutputFile(false, getCurrentFile());
1127   if (!OSP)
1128     return;
1129 
1130   raw_ostream &OS = *OSP;
1131   const Preprocessor &PP = CI.getPreprocessor();
1132   const LangOptions &LangOpts = PP.getLangOpts();
1133 
1134   // FIXME: Rather than manually format the JSON (which is awkward due to
1135   // needing to remove trailing commas), this should make use of a JSON library.
1136   // FIXME: Instead of printing enums as an integral value and specifying the
1137   // type as a separate field, use introspection to print the enumerator.
1138 
1139   OS << "{\n";
1140   OS << "\n\"features\" : [\n";
1141   {
1142     llvm::SmallString<128> Str;
1143 #define FEATURE(Name, Predicate)                                               \
1144   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1145       .toVector(Str);
1146 #include "clang/Basic/Features.def"
1147 #undef FEATURE
1148     // Remove the newline and comma from the last entry to ensure this remains
1149     // valid JSON.
1150     OS << Str.substr(0, Str.size() - 2);
1151   }
1152   OS << "\n],\n";
1153 
1154   OS << "\n\"extensions\" : [\n";
1155   {
1156     llvm::SmallString<128> Str;
1157 #define EXTENSION(Name, Predicate)                                             \
1158   ("\t{\"" #Name "\" : " + llvm::Twine(Predicate ? "true" : "false") + "},\n") \
1159       .toVector(Str);
1160 #include "clang/Basic/Features.def"
1161 #undef EXTENSION
1162     // Remove the newline and comma from the last entry to ensure this remains
1163     // valid JSON.
1164     OS << Str.substr(0, Str.size() - 2);
1165   }
1166   OS << "\n]\n";
1167 
1168   OS << "}";
1169 }
1170 
1171 void PrintDependencyDirectivesSourceMinimizerAction::ExecuteAction() {
1172   CompilerInstance &CI = getCompilerInstance();
1173   SourceManager &SM = CI.getPreprocessor().getSourceManager();
1174   llvm::MemoryBufferRef FromFile = SM.getBufferOrFake(SM.getMainFileID());
1175 
1176   llvm::SmallVector<dependency_directives_scan::Token, 16> Tokens;
1177   llvm::SmallVector<dependency_directives_scan::Directive, 32> Directives;
1178   if (scanSourceForDependencyDirectives(
1179           FromFile.getBuffer(), Tokens, Directives, &CI.getDiagnostics(),
1180           SM.getLocForStartOfFile(SM.getMainFileID()))) {
1181     assert(CI.getDiagnostics().hasErrorOccurred() &&
1182            "no errors reported for failure");
1183 
1184     // Preprocess the source when verifying the diagnostics to capture the
1185     // 'expected' comments.
1186     if (CI.getDiagnosticOpts().VerifyDiagnostics) {
1187       // Make sure we don't emit new diagnostics!
1188       CI.getDiagnostics().setSuppressAllDiagnostics(true);
1189       Preprocessor &PP = getCompilerInstance().getPreprocessor();
1190       PP.EnterMainSourceFile();
1191       Token Tok;
1192       do {
1193         PP.Lex(Tok);
1194       } while (Tok.isNot(tok::eof));
1195     }
1196     return;
1197   }
1198   printDependencyDirectivesAsSource(FromFile.getBuffer(), Directives,
1199                                     llvm::outs());
1200 }
1201 
1202 void GetDependenciesByModuleNameAction::ExecuteAction() {
1203   CompilerInstance &CI = getCompilerInstance();
1204   Preprocessor &PP = CI.getPreprocessor();
1205   SourceManager &SM = PP.getSourceManager();
1206   FileID MainFileID = SM.getMainFileID();
1207   SourceLocation FileStart = SM.getLocForStartOfFile(MainFileID);
1208   SmallVector<std::pair<IdentifierInfo *, SourceLocation>, 2> Path;
1209   IdentifierInfo *ModuleID = PP.getIdentifierInfo(ModuleName);
1210   Path.push_back(std::make_pair(ModuleID, FileStart));
1211   auto ModResult = CI.loadModule(FileStart, Path, Module::Hidden, false);
1212   PPCallbacks *CB = PP.getPPCallbacks();
1213   CB->moduleImport(SourceLocation(), Path, ModResult);
1214 }
1215