1 //===--- FrontendActions.cpp ----------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Frontend/FrontendActions.h"
11 #include "clang/AST/ASTConsumer.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Frontend/ASTConsumers.h"
14 #include "clang/Frontend/ASTUnit.h"
15 #include "clang/Frontend/CompilerInstance.h"
16 #include "clang/Frontend/FrontendDiagnostic.h"
17 #include "clang/Frontend/MultiplexConsumer.h"
18 #include "clang/Frontend/Utils.h"
19 #include "clang/Lex/HeaderSearch.h"
20 #include "clang/Lex/Pragma.h"
21 #include "clang/Lex/Preprocessor.h"
22 #include "clang/Parse/Parser.h"
23 #include "clang/Serialization/ASTReader.h"
24 #include "clang/Serialization/ASTWriter.h"
25 #include "llvm/Support/FileSystem.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include <memory>
29 #include <system_error>
30 
31 using namespace clang;
32 
33 //===----------------------------------------------------------------------===//
34 // Custom Actions
35 //===----------------------------------------------------------------------===//
36 
37 std::unique_ptr<ASTConsumer>
38 InitOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
39   return llvm::make_unique<ASTConsumer>();
40 }
41 
42 void InitOnlyAction::ExecuteAction() {
43 }
44 
45 //===----------------------------------------------------------------------===//
46 // AST Consumer Actions
47 //===----------------------------------------------------------------------===//
48 
49 std::unique_ptr<ASTConsumer>
50 ASTPrintAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
51   if (raw_ostream *OS = CI.createDefaultOutputFile(false, InFile))
52     return CreateASTPrinter(OS, CI.getFrontendOpts().ASTDumpFilter);
53   return nullptr;
54 }
55 
56 std::unique_ptr<ASTConsumer>
57 ASTDumpAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
58   return CreateASTDumper(CI.getFrontendOpts().ASTDumpFilter,
59                          CI.getFrontendOpts().ASTDumpDecls,
60                          CI.getFrontendOpts().ASTDumpLookups);
61 }
62 
63 std::unique_ptr<ASTConsumer>
64 ASTDeclListAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
65   return CreateASTDeclNodeLister();
66 }
67 
68 std::unique_ptr<ASTConsumer>
69 ASTViewAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
70   return CreateASTViewer();
71 }
72 
73 std::unique_ptr<ASTConsumer>
74 DeclContextPrintAction::CreateASTConsumer(CompilerInstance &CI,
75                                           StringRef InFile) {
76   return CreateDeclContextPrinter();
77 }
78 
79 std::unique_ptr<ASTConsumer>
80 GeneratePCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
81   std::string Sysroot;
82   std::string OutputFile;
83   raw_pwrite_stream *OS =
84       ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile);
85   if (!OS)
86     return nullptr;
87 
88   if (!CI.getFrontendOpts().RelocatablePCH)
89     Sysroot.clear();
90 
91   auto Buffer = std::make_shared<PCHBuffer>();
92   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
93   Consumers.push_back(llvm::make_unique<PCHGenerator>(
94                         CI.getPreprocessor(), OutputFile, nullptr, Sysroot,
95                         Buffer, CI.getFrontendOpts().ModuleFileExtensions));
96   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
97       CI, InFile, OutputFile, OS, Buffer));
98 
99   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
100 }
101 
102 raw_pwrite_stream *GeneratePCHAction::ComputeASTConsumerArguments(
103     CompilerInstance &CI, StringRef InFile, std::string &Sysroot,
104     std::string &OutputFile) {
105   Sysroot = CI.getHeaderSearchOpts().Sysroot;
106   if (CI.getFrontendOpts().RelocatablePCH && Sysroot.empty()) {
107     CI.getDiagnostics().Report(diag::err_relocatable_without_isysroot);
108     return nullptr;
109   }
110 
111   // We use createOutputFile here because this is exposed via libclang, and we
112   // must disable the RemoveFileOnSignal behavior.
113   // We use a temporary to avoid race conditions.
114   raw_pwrite_stream *OS =
115       CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
116                           /*RemoveFileOnSignal=*/false, InFile,
117                           /*Extension=*/"", /*useTemporary=*/true);
118   if (!OS)
119     return nullptr;
120 
121   OutputFile = CI.getFrontendOpts().OutputFile;
122   return OS;
123 }
124 
125 std::unique_ptr<ASTConsumer>
126 GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
127                                         StringRef InFile) {
128   std::string Sysroot;
129   std::string OutputFile;
130   raw_pwrite_stream *OS =
131       ComputeASTConsumerArguments(CI, InFile, Sysroot, OutputFile);
132   if (!OS)
133     return nullptr;
134 
135   auto Buffer = std::make_shared<PCHBuffer>();
136   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
137 
138   Consumers.push_back(llvm::make_unique<PCHGenerator>(
139                         CI.getPreprocessor(), OutputFile, Module, Sysroot,
140                         Buffer, CI.getFrontendOpts().ModuleFileExtensions,
141                         /*AllowASTWithErrors=*/false,
142                         /*IncludeTimestamps=*/
143                           +CI.getFrontendOpts().BuildingImplicitModule));
144   Consumers.push_back(CI.getPCHContainerWriter().CreatePCHContainerGenerator(
145       CI, InFile, OutputFile, OS, Buffer));
146   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
147 }
148 
149 static SmallVectorImpl<char> &
150 operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
151   Includes.append(RHS.begin(), RHS.end());
152   return Includes;
153 }
154 
155 static std::error_code addHeaderInclude(StringRef HeaderName,
156                                         SmallVectorImpl<char> &Includes,
157                                         const LangOptions &LangOpts,
158                                         bool IsExternC) {
159   if (IsExternC && LangOpts.CPlusPlus)
160     Includes += "extern \"C\" {\n";
161   if (LangOpts.ObjC1)
162     Includes += "#import \"";
163   else
164     Includes += "#include \"";
165 
166   Includes += HeaderName;
167 
168   Includes += "\"\n";
169   if (IsExternC && LangOpts.CPlusPlus)
170     Includes += "}\n";
171   return std::error_code();
172 }
173 
174 /// \brief Collect the set of header includes needed to construct the given
175 /// module and update the TopHeaders file set of the module.
176 ///
177 /// \param Module The module we're collecting includes from.
178 ///
179 /// \param Includes Will be augmented with the set of \#includes or \#imports
180 /// needed to load all of the named headers.
181 static std::error_code
182 collectModuleHeaderIncludes(const LangOptions &LangOpts, FileManager &FileMgr,
183                             ModuleMap &ModMap, clang::Module *Module,
184                             SmallVectorImpl<char> &Includes) {
185   // Don't collect any headers for unavailable modules.
186   if (!Module->isAvailable())
187     return std::error_code();
188 
189   // Add includes for each of these headers.
190   for (auto HK : {Module::HK_Normal, Module::HK_Private}) {
191     for (Module::Header &H : Module->Headers[HK]) {
192       Module->addTopHeader(H.Entry);
193       // Use the path as specified in the module map file. We'll look for this
194       // file relative to the module build directory (the directory containing
195       // the module map file) so this will find the same file that we found
196       // while parsing the module map.
197       if (std::error_code Err = addHeaderInclude(H.NameAsWritten, Includes,
198                                                  LangOpts, Module->IsExternC))
199         return Err;
200     }
201   }
202   // Note that Module->PrivateHeaders will not be a TopHeader.
203 
204   if (Module::Header UmbrellaHeader = Module->getUmbrellaHeader()) {
205     Module->addTopHeader(UmbrellaHeader.Entry);
206     if (Module->Parent) {
207       // Include the umbrella header for submodules.
208       if (std::error_code Err = addHeaderInclude(UmbrellaHeader.NameAsWritten,
209                                                  Includes, LangOpts,
210                                                  Module->IsExternC))
211         return Err;
212     }
213   } else if (Module::DirectoryName UmbrellaDir = Module->getUmbrellaDir()) {
214     // Add all of the headers we find in this subdirectory.
215     std::error_code EC;
216     SmallString<128> DirNative;
217     llvm::sys::path::native(UmbrellaDir.Entry->getName(), DirNative);
218     for (llvm::sys::fs::recursive_directory_iterator Dir(DirNative, EC),
219                                                      DirEnd;
220          Dir != DirEnd && !EC; Dir.increment(EC)) {
221       // Check whether this entry has an extension typically associated with
222       // headers.
223       if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->path()))
224           .Cases(".h", ".H", ".hh", ".hpp", true)
225           .Default(false))
226         continue;
227 
228       const FileEntry *Header = FileMgr.getFile(Dir->path());
229       // FIXME: This shouldn't happen unless there is a file system race. Is
230       // that worth diagnosing?
231       if (!Header)
232         continue;
233 
234       // If this header is marked 'unavailable' in this module, don't include
235       // it.
236       if (ModMap.isHeaderUnavailableInModule(Header, Module))
237         continue;
238 
239       // Compute the relative path from the directory to this file.
240       SmallVector<StringRef, 16> Components;
241       auto PathIt = llvm::sys::path::rbegin(Dir->path());
242       for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
243         Components.push_back(*PathIt);
244       SmallString<128> RelativeHeader(UmbrellaDir.NameAsWritten);
245       for (auto It = Components.rbegin(), End = Components.rend(); It != End;
246            ++It)
247         llvm::sys::path::append(RelativeHeader, *It);
248 
249       // Include this header as part of the umbrella directory.
250       Module->addTopHeader(Header);
251       if (std::error_code Err = addHeaderInclude(RelativeHeader, Includes,
252                                                  LangOpts, Module->IsExternC))
253         return Err;
254     }
255 
256     if (EC)
257       return EC;
258   }
259 
260   // Recurse into submodules.
261   for (clang::Module::submodule_iterator Sub = Module->submodule_begin(),
262                                       SubEnd = Module->submodule_end();
263        Sub != SubEnd; ++Sub)
264     if (std::error_code Err = collectModuleHeaderIncludes(
265             LangOpts, FileMgr, ModMap, *Sub, Includes))
266       return Err;
267 
268   return std::error_code();
269 }
270 
271 bool GenerateModuleAction::BeginSourceFileAction(CompilerInstance &CI,
272                                                  StringRef Filename) {
273   CI.getLangOpts().CompilingModule = true;
274 
275   // Find the module map file.
276   const FileEntry *ModuleMap =
277       CI.getFileManager().getFile(Filename, /*openFile*/true);
278   if (!ModuleMap)  {
279     CI.getDiagnostics().Report(diag::err_module_map_not_found)
280       << Filename;
281     return false;
282   }
283 
284   // Set up embedding for any specified files. Do this before we load any
285   // source files, including the primary module map for the compilation.
286   for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
287     if (const auto *FE = CI.getFileManager().getFile(F, /*openFile*/true))
288       CI.getSourceManager().setFileIsTransient(FE);
289     else
290       CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
291   }
292   if (CI.getFrontendOpts().ModulesEmbedAllFiles)
293     CI.getSourceManager().setAllFilesAreTransient(true);
294 
295   // Parse the module map file.
296   HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
297   if (HS.loadModuleMapFile(ModuleMap, IsSystem))
298     return false;
299 
300   if (CI.getLangOpts().CurrentModule.empty()) {
301     CI.getDiagnostics().Report(diag::err_missing_module_name);
302 
303     // FIXME: Eventually, we could consider asking whether there was just
304     // a single module described in the module map, and use that as a
305     // default. Then it would be fairly trivial to just "compile" a module
306     // map with a single module (the common case).
307     return false;
308   }
309 
310   // If we're being run from the command-line, the module build stack will not
311   // have been filled in yet, so complete it now in order to allow us to detect
312   // module cycles.
313   SourceManager &SourceMgr = CI.getSourceManager();
314   if (SourceMgr.getModuleBuildStack().empty())
315     SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
316                                    FullSourceLoc(SourceLocation(), SourceMgr));
317 
318   // Dig out the module definition.
319   Module = HS.lookupModule(CI.getLangOpts().CurrentModule,
320                            /*AllowSearch=*/false);
321   if (!Module) {
322     CI.getDiagnostics().Report(diag::err_missing_module)
323       << CI.getLangOpts().CurrentModule << Filename;
324 
325     return false;
326   }
327 
328   // Check whether we can build this module at all.
329   clang::Module::Requirement Requirement;
330   clang::Module::UnresolvedHeaderDirective MissingHeader;
331   if (!Module->isAvailable(CI.getLangOpts(), CI.getTarget(), Requirement,
332                            MissingHeader)) {
333     if (MissingHeader.FileNameLoc.isValid()) {
334       CI.getDiagnostics().Report(MissingHeader.FileNameLoc,
335                                  diag::err_module_header_missing)
336         << MissingHeader.IsUmbrella << MissingHeader.FileName;
337     } else {
338       CI.getDiagnostics().Report(diag::err_module_unavailable)
339         << Module->getFullModuleName()
340         << Requirement.second << Requirement.first;
341     }
342 
343     return false;
344   }
345 
346   if (ModuleMapForUniquing && ModuleMapForUniquing != ModuleMap) {
347     Module->IsInferred = true;
348     HS.getModuleMap().setInferredModuleAllowedBy(Module, ModuleMapForUniquing);
349   } else {
350     ModuleMapForUniquing = ModuleMap;
351   }
352 
353   FileManager &FileMgr = CI.getFileManager();
354 
355   // Collect the set of #includes we need to build the module.
356   SmallString<256> HeaderContents;
357   std::error_code Err = std::error_code();
358   if (Module::Header UmbrellaHeader = Module->getUmbrellaHeader())
359     Err = addHeaderInclude(UmbrellaHeader.NameAsWritten, HeaderContents,
360                            CI.getLangOpts(), Module->IsExternC);
361   if (!Err)
362     Err = collectModuleHeaderIncludes(
363         CI.getLangOpts(), FileMgr,
364         CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), Module,
365         HeaderContents);
366 
367   if (Err) {
368     CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
369       << Module->getFullModuleName() << Err.message();
370     return false;
371   }
372 
373   // Inform the preprocessor that includes from within the input buffer should
374   // be resolved relative to the build directory of the module map file.
375   CI.getPreprocessor().setMainFileDir(Module->Directory);
376 
377   std::unique_ptr<llvm::MemoryBuffer> InputBuffer =
378       llvm::MemoryBuffer::getMemBufferCopy(HeaderContents,
379                                            Module::getModuleInputBufferName());
380   // Ownership of InputBuffer will be transferred to the SourceManager.
381   setCurrentInput(FrontendInputFile(InputBuffer.release(), getCurrentFileKind(),
382                                     Module->IsSystem));
383   return true;
384 }
385 
386 raw_pwrite_stream *GenerateModuleAction::ComputeASTConsumerArguments(
387     CompilerInstance &CI, StringRef InFile, std::string &Sysroot,
388     std::string &OutputFile) {
389   // If no output file was provided, figure out where this module would go
390   // in the module cache.
391   if (CI.getFrontendOpts().OutputFile.empty()) {
392     HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
393     CI.getFrontendOpts().OutputFile =
394         HS.getModuleFileName(CI.getLangOpts().CurrentModule,
395                              ModuleMapForUniquing->getName());
396   }
397 
398   // We use createOutputFile here because this is exposed via libclang, and we
399   // must disable the RemoveFileOnSignal behavior.
400   // We use a temporary to avoid race conditions.
401   raw_pwrite_stream *OS =
402       CI.createOutputFile(CI.getFrontendOpts().OutputFile, /*Binary=*/true,
403                           /*RemoveFileOnSignal=*/false, InFile,
404                           /*Extension=*/"", /*useTemporary=*/true,
405                           /*CreateMissingDirectories=*/true);
406   if (!OS)
407     return nullptr;
408 
409   OutputFile = CI.getFrontendOpts().OutputFile;
410   return OS;
411 }
412 
413 std::unique_ptr<ASTConsumer>
414 SyntaxOnlyAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
415   return llvm::make_unique<ASTConsumer>();
416 }
417 
418 std::unique_ptr<ASTConsumer>
419 DumpModuleInfoAction::CreateASTConsumer(CompilerInstance &CI,
420                                         StringRef InFile) {
421   return llvm::make_unique<ASTConsumer>();
422 }
423 
424 std::unique_ptr<ASTConsumer>
425 VerifyPCHAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
426   return llvm::make_unique<ASTConsumer>();
427 }
428 
429 void VerifyPCHAction::ExecuteAction() {
430   CompilerInstance &CI = getCompilerInstance();
431   bool Preamble = CI.getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
432   const std::string &Sysroot = CI.getHeaderSearchOpts().Sysroot;
433   std::unique_ptr<ASTReader> Reader(new ASTReader(
434       CI.getPreprocessor(), CI.getASTContext(), CI.getPCHContainerReader(),
435       CI.getFrontendOpts().ModuleFileExtensions,
436       Sysroot.empty() ? "" : Sysroot.c_str(),
437       /*DisableValidation*/ false,
438       /*AllowPCHWithCompilerErrors*/ false,
439       /*AllowConfigurationMismatch*/ true,
440       /*ValidateSystemInputs*/ true));
441 
442   Reader->ReadAST(getCurrentFile(),
443                   Preamble ? serialization::MK_Preamble
444                            : serialization::MK_PCH,
445                   SourceLocation(),
446                   ASTReader::ARR_ConfigurationMismatch);
447 }
448 
449 namespace {
450   /// \brief AST reader listener that dumps module information for a module
451   /// file.
452   class DumpModuleInfoListener : public ASTReaderListener {
453     llvm::raw_ostream &Out;
454 
455   public:
456     DumpModuleInfoListener(llvm::raw_ostream &Out) : Out(Out) { }
457 
458 #define DUMP_BOOLEAN(Value, Text)                       \
459     Out.indent(4) << Text << ": " << (Value? "Yes" : "No") << "\n"
460 
461     bool ReadFullVersionInformation(StringRef FullVersion) override {
462       Out.indent(2)
463         << "Generated by "
464         << (FullVersion == getClangFullRepositoryVersion()? "this"
465                                                           : "a different")
466         << " Clang: " << FullVersion << "\n";
467       return ASTReaderListener::ReadFullVersionInformation(FullVersion);
468     }
469 
470     void ReadModuleName(StringRef ModuleName) override {
471       Out.indent(2) << "Module name: " << ModuleName << "\n";
472     }
473     void ReadModuleMapFile(StringRef ModuleMapPath) override {
474       Out.indent(2) << "Module map file: " << ModuleMapPath << "\n";
475     }
476 
477     bool ReadLanguageOptions(const LangOptions &LangOpts, bool Complain,
478                              bool AllowCompatibleDifferences) override {
479       Out.indent(2) << "Language options:\n";
480 #define LANGOPT(Name, Bits, Default, Description) \
481       DUMP_BOOLEAN(LangOpts.Name, Description);
482 #define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
483       Out.indent(4) << Description << ": "                   \
484                     << static_cast<unsigned>(LangOpts.get##Name()) << "\n";
485 #define VALUE_LANGOPT(Name, Bits, Default, Description) \
486       Out.indent(4) << Description << ": " << LangOpts.Name << "\n";
487 #define BENIGN_LANGOPT(Name, Bits, Default, Description)
488 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description)
489 #include "clang/Basic/LangOptions.def"
490 
491       if (!LangOpts.ModuleFeatures.empty()) {
492         Out.indent(4) << "Module features:\n";
493         for (StringRef Feature : LangOpts.ModuleFeatures)
494           Out.indent(6) << Feature << "\n";
495       }
496 
497       return false;
498     }
499 
500     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
501                            bool AllowCompatibleDifferences) override {
502       Out.indent(2) << "Target options:\n";
503       Out.indent(4) << "  Triple: " << TargetOpts.Triple << "\n";
504       Out.indent(4) << "  CPU: " << TargetOpts.CPU << "\n";
505       Out.indent(4) << "  ABI: " << TargetOpts.ABI << "\n";
506 
507       if (!TargetOpts.FeaturesAsWritten.empty()) {
508         Out.indent(4) << "Target features:\n";
509         for (unsigned I = 0, N = TargetOpts.FeaturesAsWritten.size();
510              I != N; ++I) {
511           Out.indent(6) << TargetOpts.FeaturesAsWritten[I] << "\n";
512         }
513       }
514 
515       return false;
516     }
517 
518     bool ReadDiagnosticOptions(IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts,
519                                bool Complain) override {
520       Out.indent(2) << "Diagnostic options:\n";
521 #define DIAGOPT(Name, Bits, Default) DUMP_BOOLEAN(DiagOpts->Name, #Name);
522 #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
523       Out.indent(4) << #Name << ": " << DiagOpts->get##Name() << "\n";
524 #define VALUE_DIAGOPT(Name, Bits, Default) \
525       Out.indent(4) << #Name << ": " << DiagOpts->Name << "\n";
526 #include "clang/Basic/DiagnosticOptions.def"
527 
528       Out.indent(4) << "Diagnostic flags:\n";
529       for (const std::string &Warning : DiagOpts->Warnings)
530         Out.indent(6) << "-W" << Warning << "\n";
531       for (const std::string &Remark : DiagOpts->Remarks)
532         Out.indent(6) << "-R" << Remark << "\n";
533 
534       return false;
535     }
536 
537     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
538                                  StringRef SpecificModuleCachePath,
539                                  bool Complain) override {
540       Out.indent(2) << "Header search options:\n";
541       Out.indent(4) << "System root [-isysroot=]: '" << HSOpts.Sysroot << "'\n";
542       Out.indent(4) << "Module Cache: '" << SpecificModuleCachePath << "'\n";
543       DUMP_BOOLEAN(HSOpts.UseBuiltinIncludes,
544                    "Use builtin include directories [-nobuiltininc]");
545       DUMP_BOOLEAN(HSOpts.UseStandardSystemIncludes,
546                    "Use standard system include directories [-nostdinc]");
547       DUMP_BOOLEAN(HSOpts.UseStandardCXXIncludes,
548                    "Use standard C++ include directories [-nostdinc++]");
549       DUMP_BOOLEAN(HSOpts.UseLibcxx,
550                    "Use libc++ (rather than libstdc++) [-stdlib=]");
551       return false;
552     }
553 
554     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
555                                  bool Complain,
556                                  std::string &SuggestedPredefines) override {
557       Out.indent(2) << "Preprocessor options:\n";
558       DUMP_BOOLEAN(PPOpts.UsePredefines,
559                    "Uses compiler/target-specific predefines [-undef]");
560       DUMP_BOOLEAN(PPOpts.DetailedRecord,
561                    "Uses detailed preprocessing record (for indexing)");
562 
563       if (!PPOpts.Macros.empty()) {
564         Out.indent(4) << "Predefined macros:\n";
565       }
566 
567       for (std::vector<std::pair<std::string, bool/*isUndef*/> >::const_iterator
568              I = PPOpts.Macros.begin(), IEnd = PPOpts.Macros.end();
569            I != IEnd; ++I) {
570         Out.indent(6);
571         if (I->second)
572           Out << "-U";
573         else
574           Out << "-D";
575         Out << I->first << "\n";
576       }
577       return false;
578     }
579 
580     /// Indicates that a particular module file extension has been read.
581     void readModuleFileExtension(
582            const ModuleFileExtensionMetadata &Metadata) override {
583       Out.indent(2) << "Module file extension '"
584                     << Metadata.BlockName << "' " << Metadata.MajorVersion
585                     << "." << Metadata.MinorVersion;
586       if (!Metadata.UserInfo.empty()) {
587         Out << ": ";
588         Out.write_escaped(Metadata.UserInfo);
589       }
590 
591       Out << "\n";
592     }
593 #undef DUMP_BOOLEAN
594   };
595 }
596 
597 void DumpModuleInfoAction::ExecuteAction() {
598   // Set up the output file.
599   std::unique_ptr<llvm::raw_fd_ostream> OutFile;
600   StringRef OutputFileName = getCompilerInstance().getFrontendOpts().OutputFile;
601   if (!OutputFileName.empty() && OutputFileName != "-") {
602     std::error_code EC;
603     OutFile.reset(new llvm::raw_fd_ostream(OutputFileName.str(), EC,
604                                            llvm::sys::fs::F_Text));
605   }
606   llvm::raw_ostream &Out = OutFile.get()? *OutFile.get() : llvm::outs();
607 
608   Out << "Information for module file '" << getCurrentFile() << "':\n";
609   DumpModuleInfoListener Listener(Out);
610   ASTReader::readASTFileControlBlock(
611       getCurrentFile(), getCompilerInstance().getFileManager(),
612       getCompilerInstance().getPCHContainerReader(),
613       /*FindModuleFileExtensions=*/true, Listener);
614 }
615 
616 //===----------------------------------------------------------------------===//
617 // Preprocessor Actions
618 //===----------------------------------------------------------------------===//
619 
620 void DumpRawTokensAction::ExecuteAction() {
621   Preprocessor &PP = getCompilerInstance().getPreprocessor();
622   SourceManager &SM = PP.getSourceManager();
623 
624   // Start lexing the specified input file.
625   const llvm::MemoryBuffer *FromFile = SM.getBuffer(SM.getMainFileID());
626   Lexer RawLex(SM.getMainFileID(), FromFile, SM, PP.getLangOpts());
627   RawLex.SetKeepWhitespaceMode(true);
628 
629   Token RawTok;
630   RawLex.LexFromRawLexer(RawTok);
631   while (RawTok.isNot(tok::eof)) {
632     PP.DumpToken(RawTok, true);
633     llvm::errs() << "\n";
634     RawLex.LexFromRawLexer(RawTok);
635   }
636 }
637 
638 void DumpTokensAction::ExecuteAction() {
639   Preprocessor &PP = getCompilerInstance().getPreprocessor();
640   // Start preprocessing the specified input file.
641   Token Tok;
642   PP.EnterMainSourceFile();
643   do {
644     PP.Lex(Tok);
645     PP.DumpToken(Tok, true);
646     llvm::errs() << "\n";
647   } while (Tok.isNot(tok::eof));
648 }
649 
650 void GeneratePTHAction::ExecuteAction() {
651   CompilerInstance &CI = getCompilerInstance();
652   raw_pwrite_stream *OS = CI.createDefaultOutputFile(true, getCurrentFile());
653   if (!OS)
654     return;
655 
656   CacheTokens(CI.getPreprocessor(), OS);
657 }
658 
659 void PreprocessOnlyAction::ExecuteAction() {
660   Preprocessor &PP = getCompilerInstance().getPreprocessor();
661 
662   // Ignore unknown pragmas.
663   PP.IgnorePragmas();
664 
665   Token Tok;
666   // Start parsing the specified input file.
667   PP.EnterMainSourceFile();
668   do {
669     PP.Lex(Tok);
670   } while (Tok.isNot(tok::eof));
671 }
672 
673 void PrintPreprocessedAction::ExecuteAction() {
674   CompilerInstance &CI = getCompilerInstance();
675   // Output file may need to be set to 'Binary', to avoid converting Unix style
676   // line feeds (<LF>) to Microsoft style line feeds (<CR><LF>).
677   //
678   // Look to see what type of line endings the file uses. If there's a
679   // CRLF, then we won't open the file up in binary mode. If there is
680   // just an LF or CR, then we will open the file up in binary mode.
681   // In this fashion, the output format should match the input format, unless
682   // the input format has inconsistent line endings.
683   //
684   // This should be a relatively fast operation since most files won't have
685   // all of their source code on a single line. However, that is still a
686   // concern, so if we scan for too long, we'll just assume the file should
687   // be opened in binary mode.
688   bool BinaryMode = true;
689   bool InvalidFile = false;
690   const SourceManager& SM = CI.getSourceManager();
691   const llvm::MemoryBuffer *Buffer = SM.getBuffer(SM.getMainFileID(),
692                                                      &InvalidFile);
693   if (!InvalidFile) {
694     const char *cur = Buffer->getBufferStart();
695     const char *end = Buffer->getBufferEnd();
696     const char *next = (cur != end) ? cur + 1 : end;
697 
698     // Limit ourselves to only scanning 256 characters into the source
699     // file.  This is mostly a sanity check in case the file has no
700     // newlines whatsoever.
701     if (end - cur > 256) end = cur + 256;
702 
703     while (next < end) {
704       if (*cur == 0x0D) {  // CR
705         if (*next == 0x0A)  // CRLF
706           BinaryMode = false;
707 
708         break;
709       } else if (*cur == 0x0A)  // LF
710         break;
711 
712       ++cur;
713       ++next;
714     }
715   }
716 
717   raw_ostream *OS = CI.createDefaultOutputFile(BinaryMode, getCurrentFile());
718   if (!OS) return;
719 
720   DoPrintPreprocessedInput(CI.getPreprocessor(), OS,
721                            CI.getPreprocessorOutputOpts());
722 }
723 
724 void PrintPreambleAction::ExecuteAction() {
725   switch (getCurrentFileKind()) {
726   case IK_C:
727   case IK_CXX:
728   case IK_ObjC:
729   case IK_ObjCXX:
730   case IK_OpenCL:
731   case IK_CUDA:
732     break;
733 
734   case IK_None:
735   case IK_Asm:
736   case IK_PreprocessedC:
737   case IK_PreprocessedCuda:
738   case IK_PreprocessedCXX:
739   case IK_PreprocessedObjC:
740   case IK_PreprocessedObjCXX:
741   case IK_AST:
742   case IK_LLVM_IR:
743     // We can't do anything with these.
744     return;
745   }
746 
747   CompilerInstance &CI = getCompilerInstance();
748   auto Buffer = CI.getFileManager().getBufferForFile(getCurrentFile());
749   if (Buffer) {
750     unsigned Preamble =
751         Lexer::ComputePreamble((*Buffer)->getBuffer(), CI.getLangOpts()).first;
752     llvm::outs().write((*Buffer)->getBufferStart(), Preamble);
753   }
754 }
755