xref: /freebsd/contrib/llvm-project/clang/lib/Frontend/FrontendAction.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 //===--- FrontendAction.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/FrontendAction.h"
10 #include "clang/AST/ASTConsumer.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/AST/DeclGroup.h"
13 #include "clang/Basic/Builtins.h"
14 #include "clang/Basic/DiagnosticOptions.h"
15 #include "clang/Basic/FileEntry.h"
16 #include "clang/Basic/LangStandard.h"
17 #include "clang/Basic/Sarif.h"
18 #include "clang/Basic/Stack.h"
19 #include "clang/Frontend/ASTUnit.h"
20 #include "clang/Frontend/CompilerInstance.h"
21 #include "clang/Frontend/FrontendDiagnostic.h"
22 #include "clang/Frontend/FrontendPluginRegistry.h"
23 #include "clang/Frontend/LayoutOverrideSource.h"
24 #include "clang/Frontend/MultiplexConsumer.h"
25 #include "clang/Frontend/SARIFDiagnosticPrinter.h"
26 #include "clang/Frontend/Utils.h"
27 #include "clang/Lex/HeaderSearch.h"
28 #include "clang/Lex/LiteralSupport.h"
29 #include "clang/Lex/Preprocessor.h"
30 #include "clang/Lex/PreprocessorOptions.h"
31 #include "clang/Parse/ParseAST.h"
32 #include "clang/Sema/HLSLExternalSemaSource.h"
33 #include "clang/Sema/MultiplexExternalSemaSource.h"
34 #include "clang/Serialization/ASTDeserializationListener.h"
35 #include "clang/Serialization/ASTReader.h"
36 #include "clang/Serialization/GlobalModuleIndex.h"
37 #include "llvm/ADT/ScopeExit.h"
38 #include "llvm/Support/BuryPointer.h"
39 #include "llvm/Support/ErrorHandling.h"
40 #include "llvm/Support/FileSystem.h"
41 #include "llvm/Support/Path.h"
42 #include "llvm/Support/Timer.h"
43 #include "llvm/Support/raw_ostream.h"
44 #include <memory>
45 #include <system_error>
46 using namespace clang;
47 
48 LLVM_INSTANTIATE_REGISTRY(FrontendPluginRegistry)
49 
50 namespace {
51 
52 class DelegatingDeserializationListener : public ASTDeserializationListener {
53   ASTDeserializationListener *Previous;
54   bool DeletePrevious;
55 
56 public:
DelegatingDeserializationListener(ASTDeserializationListener * Previous,bool DeletePrevious)57   explicit DelegatingDeserializationListener(
58       ASTDeserializationListener *Previous, bool DeletePrevious)
59       : Previous(Previous), DeletePrevious(DeletePrevious) {}
~DelegatingDeserializationListener()60   ~DelegatingDeserializationListener() override {
61     if (DeletePrevious)
62       delete Previous;
63   }
64 
65   DelegatingDeserializationListener(const DelegatingDeserializationListener &) =
66       delete;
67   DelegatingDeserializationListener &
68   operator=(const DelegatingDeserializationListener &) = delete;
69 
ReaderInitialized(ASTReader * Reader)70   void ReaderInitialized(ASTReader *Reader) override {
71     if (Previous)
72       Previous->ReaderInitialized(Reader);
73   }
IdentifierRead(serialization::IdentifierID ID,IdentifierInfo * II)74   void IdentifierRead(serialization::IdentifierID ID,
75                       IdentifierInfo *II) override {
76     if (Previous)
77       Previous->IdentifierRead(ID, II);
78   }
TypeRead(serialization::TypeIdx Idx,QualType T)79   void TypeRead(serialization::TypeIdx Idx, QualType T) override {
80     if (Previous)
81       Previous->TypeRead(Idx, T);
82   }
DeclRead(GlobalDeclID ID,const Decl * D)83   void DeclRead(GlobalDeclID ID, const Decl *D) override {
84     if (Previous)
85       Previous->DeclRead(ID, D);
86   }
SelectorRead(serialization::SelectorID ID,Selector Sel)87   void SelectorRead(serialization::SelectorID ID, Selector Sel) override {
88     if (Previous)
89       Previous->SelectorRead(ID, Sel);
90   }
MacroDefinitionRead(serialization::PreprocessedEntityID PPID,MacroDefinitionRecord * MD)91   void MacroDefinitionRead(serialization::PreprocessedEntityID PPID,
92                            MacroDefinitionRecord *MD) override {
93     if (Previous)
94       Previous->MacroDefinitionRead(PPID, MD);
95   }
96 };
97 
98 /// Dumps deserialized declarations.
99 class DeserializedDeclsDumper : public DelegatingDeserializationListener {
100 public:
DeserializedDeclsDumper(ASTDeserializationListener * Previous,bool DeletePrevious)101   explicit DeserializedDeclsDumper(ASTDeserializationListener *Previous,
102                                    bool DeletePrevious)
103       : DelegatingDeserializationListener(Previous, DeletePrevious) {}
104 
DeclRead(GlobalDeclID ID,const Decl * D)105   void DeclRead(GlobalDeclID ID, const Decl *D) override {
106     llvm::outs() << "PCH DECL: " << D->getDeclKindName();
107     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D)) {
108       llvm::outs() << " - ";
109       ND->printQualifiedName(llvm::outs());
110     }
111     llvm::outs() << "\n";
112 
113     DelegatingDeserializationListener::DeclRead(ID, D);
114   }
115 };
116 
117 /// Checks deserialized declarations and emits error if a name
118 /// matches one given in command-line using -error-on-deserialized-decl.
119 class DeserializedDeclsChecker : public DelegatingDeserializationListener {
120   ASTContext &Ctx;
121   std::set<std::string> NamesToCheck;
122 
123 public:
DeserializedDeclsChecker(ASTContext & Ctx,const std::set<std::string> & NamesToCheck,ASTDeserializationListener * Previous,bool DeletePrevious)124   DeserializedDeclsChecker(ASTContext &Ctx,
125                            const std::set<std::string> &NamesToCheck,
126                            ASTDeserializationListener *Previous,
127                            bool DeletePrevious)
128       : DelegatingDeserializationListener(Previous, DeletePrevious), Ctx(Ctx),
129         NamesToCheck(NamesToCheck) {}
130 
DeclRead(GlobalDeclID ID,const Decl * D)131   void DeclRead(GlobalDeclID ID, const Decl *D) override {
132     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
133       if (NamesToCheck.find(ND->getNameAsString()) != NamesToCheck.end()) {
134         unsigned DiagID
135           = Ctx.getDiagnostics().getCustomDiagID(DiagnosticsEngine::Error,
136                                                  "%0 was deserialized");
137         Ctx.getDiagnostics().Report(Ctx.getFullLoc(D->getLocation()), DiagID)
138             << ND;
139       }
140 
141     DelegatingDeserializationListener::DeclRead(ID, D);
142   }
143 };
144 
145 } // end anonymous namespace
146 
FrontendAction()147 FrontendAction::FrontendAction() : Instance(nullptr) {}
148 
~FrontendAction()149 FrontendAction::~FrontendAction() {}
150 
setCurrentInput(const FrontendInputFile & CurrentInput,std::unique_ptr<ASTUnit> AST)151 void FrontendAction::setCurrentInput(const FrontendInputFile &CurrentInput,
152                                      std::unique_ptr<ASTUnit> AST) {
153   this->CurrentInput = CurrentInput;
154   CurrentASTUnit = std::move(AST);
155 }
156 
getCurrentModule() const157 Module *FrontendAction::getCurrentModule() const {
158   CompilerInstance &CI = getCompilerInstance();
159   return CI.getPreprocessor().getHeaderSearchInfo().lookupModule(
160       CI.getLangOpts().CurrentModule, SourceLocation(), /*AllowSearch*/false);
161 }
162 
163 std::unique_ptr<ASTConsumer>
CreateWrappedASTConsumer(CompilerInstance & CI,StringRef InFile)164 FrontendAction::CreateWrappedASTConsumer(CompilerInstance &CI,
165                                          StringRef InFile) {
166   std::unique_ptr<ASTConsumer> Consumer = CreateASTConsumer(CI, InFile);
167   if (!Consumer)
168     return nullptr;
169 
170   // Validate -add-plugin args.
171   bool FoundAllPlugins = true;
172   for (const std::string &Arg : CI.getFrontendOpts().AddPluginActions) {
173     bool Found = false;
174     for (const FrontendPluginRegistry::entry &Plugin :
175          FrontendPluginRegistry::entries()) {
176       if (Plugin.getName() == Arg)
177         Found = true;
178     }
179     if (!Found) {
180       CI.getDiagnostics().Report(diag::err_fe_invalid_plugin_name) << Arg;
181       FoundAllPlugins = false;
182     }
183   }
184   if (!FoundAllPlugins)
185     return nullptr;
186 
187   // If there are no registered plugins we don't need to wrap the consumer
188   if (FrontendPluginRegistry::begin() == FrontendPluginRegistry::end())
189     return Consumer;
190 
191   // If this is a code completion run, avoid invoking the plugin consumers
192   if (CI.hasCodeCompletionConsumer())
193     return Consumer;
194 
195   // Collect the list of plugins that go before the main action (in Consumers)
196   // or after it (in AfterConsumers)
197   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
198   std::vector<std::unique_ptr<ASTConsumer>> AfterConsumers;
199   for (const FrontendPluginRegistry::entry &Plugin :
200        FrontendPluginRegistry::entries()) {
201     std::unique_ptr<PluginASTAction> P = Plugin.instantiate();
202     PluginASTAction::ActionType ActionType = P->getActionType();
203     if (ActionType == PluginASTAction::CmdlineAfterMainAction ||
204         ActionType == PluginASTAction::CmdlineBeforeMainAction) {
205       // This is O(|plugins| * |add_plugins|), but since both numbers are
206       // way below 50 in practice, that's ok.
207       if (llvm::is_contained(CI.getFrontendOpts().AddPluginActions,
208                              Plugin.getName())) {
209         if (ActionType == PluginASTAction::CmdlineBeforeMainAction)
210           ActionType = PluginASTAction::AddBeforeMainAction;
211         else
212           ActionType = PluginASTAction::AddAfterMainAction;
213       }
214     }
215     if ((ActionType == PluginASTAction::AddBeforeMainAction ||
216          ActionType == PluginASTAction::AddAfterMainAction) &&
217         P->ParseArgs(
218             CI,
219             CI.getFrontendOpts().PluginArgs[std::string(Plugin.getName())])) {
220       std::unique_ptr<ASTConsumer> PluginConsumer = P->CreateASTConsumer(CI, InFile);
221       if (ActionType == PluginASTAction::AddBeforeMainAction) {
222         Consumers.push_back(std::move(PluginConsumer));
223       } else {
224         AfterConsumers.push_back(std::move(PluginConsumer));
225       }
226     }
227   }
228 
229   // Add to Consumers the main consumer, then all the plugins that go after it
230   Consumers.push_back(std::move(Consumer));
231   if (!AfterConsumers.empty()) {
232     // If we have plugins after the main consumer, which may be the codegen
233     // action, they likely will need the ASTContext, so don't clear it in the
234     // codegen action.
235     CI.getCodeGenOpts().ClearASTBeforeBackend = false;
236     for (auto &C : AfterConsumers)
237       Consumers.push_back(std::move(C));
238   }
239 
240   return std::make_unique<MultiplexConsumer>(std::move(Consumers));
241 }
242 
243 /// For preprocessed files, if the first line is the linemarker and specifies
244 /// the original source file name, use that name as the input file name.
245 /// Returns the location of the first token after the line marker directive.
246 ///
247 /// \param CI The compiler instance.
248 /// \param InputFile Populated with the filename from the line marker.
249 /// \param IsModuleMap If \c true, add a line note corresponding to this line
250 ///        directive. (We need to do this because the directive will not be
251 ///        visited by the preprocessor.)
ReadOriginalFileName(CompilerInstance & CI,std::string & InputFile,bool IsModuleMap=false)252 static SourceLocation ReadOriginalFileName(CompilerInstance &CI,
253                                            std::string &InputFile,
254                                            bool IsModuleMap = false) {
255   auto &SourceMgr = CI.getSourceManager();
256   auto MainFileID = SourceMgr.getMainFileID();
257 
258   auto MainFileBuf = SourceMgr.getBufferOrNone(MainFileID);
259   if (!MainFileBuf)
260     return SourceLocation();
261 
262   std::unique_ptr<Lexer> RawLexer(
263       new Lexer(MainFileID, *MainFileBuf, SourceMgr, CI.getLangOpts()));
264 
265   // If the first line has the syntax of
266   //
267   // # NUM "FILENAME"
268   //
269   // we use FILENAME as the input file name.
270   Token T;
271   if (RawLexer->LexFromRawLexer(T) || T.getKind() != tok::hash)
272     return SourceLocation();
273   if (RawLexer->LexFromRawLexer(T) || T.isAtStartOfLine() ||
274       T.getKind() != tok::numeric_constant)
275     return SourceLocation();
276 
277   unsigned LineNo;
278   SourceLocation LineNoLoc = T.getLocation();
279   if (IsModuleMap) {
280     llvm::SmallString<16> Buffer;
281     if (Lexer::getSpelling(LineNoLoc, Buffer, SourceMgr, CI.getLangOpts())
282             .getAsInteger(10, LineNo))
283       return SourceLocation();
284   }
285 
286   RawLexer->LexFromRawLexer(T);
287   if (T.isAtStartOfLine() || T.getKind() != tok::string_literal)
288     return SourceLocation();
289 
290   StringLiteralParser Literal(T, CI.getPreprocessor());
291   if (Literal.hadError)
292     return SourceLocation();
293   RawLexer->LexFromRawLexer(T);
294   if (T.isNot(tok::eof) && !T.isAtStartOfLine())
295     return SourceLocation();
296   InputFile = Literal.GetString().str();
297 
298   if (IsModuleMap)
299     CI.getSourceManager().AddLineNote(
300         LineNoLoc, LineNo, SourceMgr.getLineTableFilenameID(InputFile), false,
301         false, SrcMgr::C_User_ModuleMap);
302 
303   return T.getLocation();
304 }
305 
306 static SmallVectorImpl<char> &
operator +=(SmallVectorImpl<char> & Includes,StringRef RHS)307 operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
308   Includes.append(RHS.begin(), RHS.end());
309   return Includes;
310 }
311 
addHeaderInclude(StringRef HeaderName,SmallVectorImpl<char> & Includes,const LangOptions & LangOpts,bool IsExternC)312 static void addHeaderInclude(StringRef HeaderName,
313                              SmallVectorImpl<char> &Includes,
314                              const LangOptions &LangOpts,
315                              bool IsExternC) {
316   if (IsExternC && LangOpts.CPlusPlus)
317     Includes += "extern \"C\" {\n";
318   if (LangOpts.ObjC)
319     Includes += "#import \"";
320   else
321     Includes += "#include \"";
322 
323   Includes += HeaderName;
324 
325   Includes += "\"\n";
326   if (IsExternC && LangOpts.CPlusPlus)
327     Includes += "}\n";
328 }
329 
330 /// Collect the set of header includes needed to construct the given
331 /// module and update the TopHeaders file set of the module.
332 ///
333 /// \param Module The module we're collecting includes from.
334 ///
335 /// \param Includes Will be augmented with the set of \#includes or \#imports
336 /// needed to load all of the named headers.
collectModuleHeaderIncludes(const LangOptions & LangOpts,FileManager & FileMgr,DiagnosticsEngine & Diag,ModuleMap & ModMap,clang::Module * Module,SmallVectorImpl<char> & Includes)337 static std::error_code collectModuleHeaderIncludes(
338     const LangOptions &LangOpts, FileManager &FileMgr, DiagnosticsEngine &Diag,
339     ModuleMap &ModMap, clang::Module *Module, SmallVectorImpl<char> &Includes) {
340   // Don't collect any headers for unavailable modules.
341   if (!Module->isAvailable())
342     return std::error_code();
343 
344   // Resolve all lazy header directives to header files.
345   ModMap.resolveHeaderDirectives(Module, /*File=*/std::nullopt);
346 
347   // If any headers are missing, we can't build this module. In most cases,
348   // diagnostics for this should have already been produced; we only get here
349   // if explicit stat information was provided.
350   // FIXME: If the name resolves to a file with different stat information,
351   // produce a better diagnostic.
352   if (!Module->MissingHeaders.empty()) {
353     auto &MissingHeader = Module->MissingHeaders.front();
354     Diag.Report(MissingHeader.FileNameLoc, diag::err_module_header_missing)
355       << MissingHeader.IsUmbrella << MissingHeader.FileName;
356     return std::error_code();
357   }
358 
359   // Add includes for each of these headers.
360   for (auto HK : {Module::HK_Normal, Module::HK_Private}) {
361     for (Module::Header &H : Module->Headers[HK]) {
362       Module->addTopHeader(H.Entry);
363       // Use the path as specified in the module map file. We'll look for this
364       // file relative to the module build directory (the directory containing
365       // the module map file) so this will find the same file that we found
366       // while parsing the module map.
367       addHeaderInclude(H.PathRelativeToRootModuleDirectory, Includes, LangOpts,
368                        Module->IsExternC);
369     }
370   }
371   // Note that Module->PrivateHeaders will not be a TopHeader.
372 
373   if (std::optional<Module::Header> UmbrellaHeader =
374           Module->getUmbrellaHeaderAsWritten()) {
375     Module->addTopHeader(UmbrellaHeader->Entry);
376     if (Module->Parent)
377       // Include the umbrella header for submodules.
378       addHeaderInclude(UmbrellaHeader->PathRelativeToRootModuleDirectory,
379                        Includes, LangOpts, Module->IsExternC);
380   } else if (std::optional<Module::DirectoryName> UmbrellaDir =
381                  Module->getUmbrellaDirAsWritten()) {
382     // Add all of the headers we find in this subdirectory.
383     std::error_code EC;
384     SmallString<128> DirNative;
385     llvm::sys::path::native(UmbrellaDir->Entry.getName(), DirNative);
386 
387     llvm::vfs::FileSystem &FS = FileMgr.getVirtualFileSystem();
388     SmallVector<std::pair<std::string, FileEntryRef>, 8> Headers;
389     for (llvm::vfs::recursive_directory_iterator Dir(FS, DirNative, EC), End;
390          Dir != End && !EC; Dir.increment(EC)) {
391       // Check whether this entry has an extension typically associated with
392       // headers.
393       if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->path()))
394                .Cases(".h", ".H", ".hh", ".hpp", true)
395                .Default(false))
396         continue;
397 
398       auto Header = FileMgr.getOptionalFileRef(Dir->path());
399       // FIXME: This shouldn't happen unless there is a file system race. Is
400       // that worth diagnosing?
401       if (!Header)
402         continue;
403 
404       // If this header is marked 'unavailable' in this module, don't include
405       // it.
406       if (ModMap.isHeaderUnavailableInModule(*Header, Module))
407         continue;
408 
409       // Compute the relative path from the directory to this file.
410       SmallVector<StringRef, 16> Components;
411       auto PathIt = llvm::sys::path::rbegin(Dir->path());
412       for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
413         Components.push_back(*PathIt);
414       SmallString<128> RelativeHeader(
415           UmbrellaDir->PathRelativeToRootModuleDirectory);
416       for (auto It = Components.rbegin(), End = Components.rend(); It != End;
417            ++It)
418         llvm::sys::path::append(RelativeHeader, *It);
419 
420       std::string RelName = RelativeHeader.c_str();
421       Headers.push_back(std::make_pair(RelName, *Header));
422     }
423 
424     if (EC)
425       return EC;
426 
427     // Sort header paths and make the header inclusion order deterministic
428     // across different OSs and filesystems.
429     llvm::sort(Headers, llvm::less_first());
430     for (auto &H : Headers) {
431       // Include this header as part of the umbrella directory.
432       Module->addTopHeader(H.second);
433       addHeaderInclude(H.first, Includes, LangOpts, Module->IsExternC);
434     }
435   }
436 
437   // Recurse into submodules.
438   for (auto *Submodule : Module->submodules())
439     if (std::error_code Err = collectModuleHeaderIncludes(
440             LangOpts, FileMgr, Diag, ModMap, Submodule, Includes))
441       return Err;
442 
443   return std::error_code();
444 }
445 
loadModuleMapForModuleBuild(CompilerInstance & CI,bool IsSystem,bool IsPreprocessed,std::string & PresumedModuleMapFile,unsigned & Offset)446 static bool loadModuleMapForModuleBuild(CompilerInstance &CI, bool IsSystem,
447                                         bool IsPreprocessed,
448                                         std::string &PresumedModuleMapFile,
449                                         unsigned &Offset) {
450   auto &SrcMgr = CI.getSourceManager();
451   HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
452 
453   // Map the current input to a file.
454   FileID ModuleMapID = SrcMgr.getMainFileID();
455   OptionalFileEntryRef ModuleMap = SrcMgr.getFileEntryRefForID(ModuleMapID);
456   assert(ModuleMap && "MainFileID without FileEntry");
457 
458   // If the module map is preprocessed, handle the initial line marker;
459   // line directives are not part of the module map syntax in general.
460   Offset = 0;
461   if (IsPreprocessed) {
462     SourceLocation EndOfLineMarker =
463         ReadOriginalFileName(CI, PresumedModuleMapFile, /*IsModuleMap*/ true);
464     if (EndOfLineMarker.isValid())
465       Offset = CI.getSourceManager().getDecomposedLoc(EndOfLineMarker).second;
466   }
467 
468   // Load the module map file.
469   if (HS.loadModuleMapFile(*ModuleMap, IsSystem, ModuleMapID, &Offset,
470                            PresumedModuleMapFile))
471     return true;
472 
473   if (SrcMgr.getBufferOrFake(ModuleMapID).getBufferSize() == Offset)
474     Offset = 0;
475 
476   // Infer framework module if possible.
477   if (HS.getModuleMap().canInferFrameworkModule(ModuleMap->getDir())) {
478     SmallString<128> InferredFrameworkPath = ModuleMap->getDir().getName();
479     llvm::sys::path::append(InferredFrameworkPath,
480                             CI.getLangOpts().ModuleName + ".framework");
481     if (auto Dir =
482             CI.getFileManager().getOptionalDirectoryRef(InferredFrameworkPath))
483       (void)HS.getModuleMap().inferFrameworkModule(*Dir, IsSystem, nullptr);
484   }
485 
486   return false;
487 }
488 
prepareToBuildModule(CompilerInstance & CI,StringRef ModuleMapFilename)489 static Module *prepareToBuildModule(CompilerInstance &CI,
490                                     StringRef ModuleMapFilename) {
491   if (CI.getLangOpts().CurrentModule.empty()) {
492     CI.getDiagnostics().Report(diag::err_missing_module_name);
493 
494     // FIXME: Eventually, we could consider asking whether there was just
495     // a single module described in the module map, and use that as a
496     // default. Then it would be fairly trivial to just "compile" a module
497     // map with a single module (the common case).
498     return nullptr;
499   }
500 
501   // Dig out the module definition.
502   HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
503   Module *M = HS.lookupModule(CI.getLangOpts().CurrentModule, SourceLocation(),
504                               /*AllowSearch=*/true);
505   if (!M) {
506     CI.getDiagnostics().Report(diag::err_missing_module)
507       << CI.getLangOpts().CurrentModule << ModuleMapFilename;
508 
509     return nullptr;
510   }
511 
512   // Check whether we can build this module at all.
513   if (Preprocessor::checkModuleIsAvailable(CI.getLangOpts(), CI.getTarget(), *M,
514                                            CI.getDiagnostics()))
515     return nullptr;
516 
517   // Inform the preprocessor that includes from within the input buffer should
518   // be resolved relative to the build directory of the module map file.
519   CI.getPreprocessor().setMainFileDir(*M->Directory);
520 
521   // If the module was inferred from a different module map (via an expanded
522   // umbrella module definition), track that fact.
523   // FIXME: It would be preferable to fill this in as part of processing
524   // the module map, rather than adding it after the fact.
525   StringRef OriginalModuleMapName = CI.getFrontendOpts().OriginalModuleMap;
526   if (!OriginalModuleMapName.empty()) {
527     auto OriginalModuleMap =
528         CI.getFileManager().getOptionalFileRef(OriginalModuleMapName,
529                                                /*openFile*/ true);
530     if (!OriginalModuleMap) {
531       CI.getDiagnostics().Report(diag::err_module_map_not_found)
532         << OriginalModuleMapName;
533       return nullptr;
534     }
535     if (*OriginalModuleMap != CI.getSourceManager().getFileEntryRefForID(
536                                   CI.getSourceManager().getMainFileID())) {
537       M->IsInferred = true;
538       auto FileCharacter =
539           M->IsSystem ? SrcMgr::C_System_ModuleMap : SrcMgr::C_User_ModuleMap;
540       FileID OriginalModuleMapFID = CI.getSourceManager().getOrCreateFileID(
541           *OriginalModuleMap, FileCharacter);
542       CI.getPreprocessor()
543           .getHeaderSearchInfo()
544           .getModuleMap()
545           .setInferredModuleAllowedBy(M, OriginalModuleMapFID);
546     }
547   }
548 
549   // If we're being run from the command-line, the module build stack will not
550   // have been filled in yet, so complete it now in order to allow us to detect
551   // module cycles.
552   SourceManager &SourceMgr = CI.getSourceManager();
553   if (SourceMgr.getModuleBuildStack().empty())
554     SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
555                                    FullSourceLoc(SourceLocation(), SourceMgr));
556   return M;
557 }
558 
559 /// Compute the input buffer that should be used to build the specified module.
560 static std::unique_ptr<llvm::MemoryBuffer>
getInputBufferForModule(CompilerInstance & CI,Module * M)561 getInputBufferForModule(CompilerInstance &CI, Module *M) {
562   FileManager &FileMgr = CI.getFileManager();
563 
564   // Collect the set of #includes we need to build the module.
565   SmallString<256> HeaderContents;
566   std::error_code Err = std::error_code();
567   if (std::optional<Module::Header> UmbrellaHeader =
568           M->getUmbrellaHeaderAsWritten())
569     addHeaderInclude(UmbrellaHeader->PathRelativeToRootModuleDirectory,
570                      HeaderContents, CI.getLangOpts(), M->IsExternC);
571   Err = collectModuleHeaderIncludes(
572       CI.getLangOpts(), FileMgr, CI.getDiagnostics(),
573       CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), M,
574       HeaderContents);
575 
576   if (Err) {
577     CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
578       << M->getFullModuleName() << Err.message();
579     return nullptr;
580   }
581 
582   return llvm::MemoryBuffer::getMemBufferCopy(
583       HeaderContents, Module::getModuleInputBufferName());
584 }
585 
BeginSourceFile(CompilerInstance & CI,const FrontendInputFile & RealInput)586 bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
587                                      const FrontendInputFile &RealInput) {
588   FrontendInputFile Input(RealInput);
589   assert(!Instance && "Already processing a source file!");
590   assert(!Input.isEmpty() && "Unexpected empty filename!");
591   setCurrentInput(Input);
592   setCompilerInstance(&CI);
593 
594   bool HasBegunSourceFile = false;
595   bool ReplayASTFile = Input.getKind().getFormat() == InputKind::Precompiled &&
596                        usesPreprocessorOnly();
597 
598   // If we fail, reset state since the client will not end up calling the
599   // matching EndSourceFile(). All paths that return true should release this.
600   auto FailureCleanup = llvm::make_scope_exit([&]() {
601     if (HasBegunSourceFile)
602       CI.getDiagnosticClient().EndSourceFile();
603     CI.setASTConsumer(nullptr);
604     CI.clearOutputFiles(/*EraseFiles=*/true);
605     CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
606     setCurrentInput(FrontendInputFile());
607     setCompilerInstance(nullptr);
608   });
609 
610   if (!BeginInvocation(CI))
611     return false;
612 
613   // If we're replaying the build of an AST file, import it and set up
614   // the initial state from its build.
615   if (ReplayASTFile) {
616     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
617 
618     // The AST unit populates its own diagnostics engine rather than ours.
619     IntrusiveRefCntPtr<DiagnosticsEngine> ASTDiags(
620         new DiagnosticsEngine(Diags->getDiagnosticIDs(),
621                               &Diags->getDiagnosticOptions()));
622     ASTDiags->setClient(Diags->getClient(), /*OwnsClient*/false);
623 
624     // FIXME: What if the input is a memory buffer?
625     StringRef InputFile = Input.getFile();
626 
627     std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
628         std::string(InputFile), CI.getPCHContainerReader(),
629         ASTUnit::LoadPreprocessorOnly, ASTDiags, CI.getFileSystemOpts(),
630         /*HeaderSearchOptions=*/nullptr);
631     if (!AST)
632       return false;
633 
634     // Options relating to how we treat the input (but not what we do with it)
635     // are inherited from the AST unit.
636     CI.getHeaderSearchOpts() = AST->getHeaderSearchOpts();
637     CI.getPreprocessorOpts() = AST->getPreprocessorOpts();
638     CI.getLangOpts() = AST->getLangOpts();
639 
640     // Set the shared objects, these are reset when we finish processing the
641     // file, otherwise the CompilerInstance will happily destroy them.
642     CI.setFileManager(&AST->getFileManager());
643     CI.createSourceManager(CI.getFileManager());
644     CI.getSourceManager().initializeForReplay(AST->getSourceManager());
645 
646     // Preload all the module files loaded transitively by the AST unit. Also
647     // load all module map files that were parsed as part of building the AST
648     // unit.
649     if (auto ASTReader = AST->getASTReader()) {
650       auto &MM = ASTReader->getModuleManager();
651       auto &PrimaryModule = MM.getPrimaryModule();
652 
653       for (serialization::ModuleFile &MF : MM)
654         if (&MF != &PrimaryModule)
655           CI.getFrontendOpts().ModuleFiles.push_back(MF.FileName);
656 
657       ASTReader->visitTopLevelModuleMaps(PrimaryModule, [&](FileEntryRef FE) {
658         CI.getFrontendOpts().ModuleMapFiles.push_back(
659             std::string(FE.getName()));
660       });
661     }
662 
663     // Set up the input file for replay purposes.
664     auto Kind = AST->getInputKind();
665     if (Kind.getFormat() == InputKind::ModuleMap) {
666       Module *ASTModule =
667           AST->getPreprocessor().getHeaderSearchInfo().lookupModule(
668               AST->getLangOpts().CurrentModule, SourceLocation(),
669               /*AllowSearch*/ false);
670       assert(ASTModule && "module file does not define its own module");
671       Input = FrontendInputFile(ASTModule->PresumedModuleMapFile, Kind);
672     } else {
673       auto &OldSM = AST->getSourceManager();
674       FileID ID = OldSM.getMainFileID();
675       if (auto File = OldSM.getFileEntryRefForID(ID))
676         Input = FrontendInputFile(File->getName(), Kind);
677       else
678         Input = FrontendInputFile(OldSM.getBufferOrFake(ID), Kind);
679     }
680     setCurrentInput(Input, std::move(AST));
681   }
682 
683   // AST files follow a very different path, since they share objects via the
684   // AST unit.
685   if (Input.getKind().getFormat() == InputKind::Precompiled) {
686     assert(!usesPreprocessorOnly() && "this case was handled above");
687     assert(hasASTFileSupport() &&
688            "This action does not have AST file support!");
689 
690     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
691 
692     // FIXME: What if the input is a memory buffer?
693     StringRef InputFile = Input.getFile();
694 
695     std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
696         std::string(InputFile), CI.getPCHContainerReader(),
697         ASTUnit::LoadEverything, Diags, CI.getFileSystemOpts(),
698         CI.getHeaderSearchOptsPtr(), CI.getLangOptsPtr());
699 
700     if (!AST)
701       return false;
702 
703     // Inform the diagnostic client we are processing a source file.
704     CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
705     HasBegunSourceFile = true;
706 
707     // Set the shared objects, these are reset when we finish processing the
708     // file, otherwise the CompilerInstance will happily destroy them.
709     CI.setFileManager(&AST->getFileManager());
710     CI.setSourceManager(&AST->getSourceManager());
711     CI.setPreprocessor(AST->getPreprocessorPtr());
712     Preprocessor &PP = CI.getPreprocessor();
713     PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
714                                            PP.getLangOpts());
715     CI.setASTContext(&AST->getASTContext());
716 
717     setCurrentInput(Input, std::move(AST));
718 
719     // Initialize the action.
720     if (!BeginSourceFileAction(CI))
721       return false;
722 
723     // Create the AST consumer.
724     CI.setASTConsumer(CreateWrappedASTConsumer(CI, InputFile));
725     if (!CI.hasASTConsumer())
726       return false;
727 
728     FailureCleanup.release();
729     return true;
730   }
731 
732   // Set up the file and source managers, if needed.
733   if (!CI.hasFileManager()) {
734     if (!CI.createFileManager()) {
735       return false;
736     }
737   }
738   if (!CI.hasSourceManager()) {
739     CI.createSourceManager(CI.getFileManager());
740     if (CI.getDiagnosticOpts().getFormat() == DiagnosticOptions::SARIF) {
741       static_cast<SARIFDiagnosticPrinter *>(&CI.getDiagnosticClient())
742           ->setSarifWriter(
743               std::make_unique<SarifDocumentWriter>(CI.getSourceManager()));
744     }
745   }
746 
747   // Set up embedding for any specified files. Do this before we load any
748   // source files, including the primary module map for the compilation.
749   for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
750     if (auto FE = CI.getFileManager().getOptionalFileRef(F, /*openFile*/true))
751       CI.getSourceManager().setFileIsTransient(*FE);
752     else
753       CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
754   }
755   if (CI.getFrontendOpts().ModulesEmbedAllFiles)
756     CI.getSourceManager().setAllFilesAreTransient(true);
757 
758   // IR files bypass the rest of initialization.
759   if (Input.getKind().getLanguage() == Language::LLVM_IR) {
760     if (!hasIRSupport()) {
761       CI.getDiagnostics().Report(diag::err_ast_action_on_llvm_ir)
762           << Input.getFile();
763       return false;
764     }
765 
766     // Inform the diagnostic client we are processing a source file.
767     CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
768     HasBegunSourceFile = true;
769 
770     // Initialize the action.
771     if (!BeginSourceFileAction(CI))
772       return false;
773 
774     // Initialize the main file entry.
775     if (!CI.InitializeSourceManager(CurrentInput))
776       return false;
777 
778     FailureCleanup.release();
779     return true;
780   }
781 
782   // If the implicit PCH include is actually a directory, rather than
783   // a single file, search for a suitable PCH file in that directory.
784   if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
785     FileManager &FileMgr = CI.getFileManager();
786     PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
787     StringRef PCHInclude = PPOpts.ImplicitPCHInclude;
788     std::string SpecificModuleCachePath = CI.getSpecificModuleCachePath();
789     if (auto PCHDir = FileMgr.getOptionalDirectoryRef(PCHInclude)) {
790       std::error_code EC;
791       SmallString<128> DirNative;
792       llvm::sys::path::native(PCHDir->getName(), DirNative);
793       bool Found = false;
794       llvm::vfs::FileSystem &FS = FileMgr.getVirtualFileSystem();
795       for (llvm::vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC),
796                                          DirEnd;
797            Dir != DirEnd && !EC; Dir.increment(EC)) {
798         // Check whether this is an acceptable AST file.
799         if (ASTReader::isAcceptableASTFile(
800                 Dir->path(), FileMgr, CI.getModuleCache(),
801                 CI.getPCHContainerReader(), CI.getLangOpts(),
802                 CI.getTargetOpts(), CI.getPreprocessorOpts(),
803                 SpecificModuleCachePath, /*RequireStrictOptionMatches=*/true)) {
804           PPOpts.ImplicitPCHInclude = std::string(Dir->path());
805           Found = true;
806           break;
807         }
808       }
809 
810       if (!Found) {
811         CI.getDiagnostics().Report(diag::err_fe_no_pch_in_dir) << PCHInclude;
812         return false;
813       }
814     }
815   }
816 
817   // Set up the preprocessor if needed. When parsing model files the
818   // preprocessor of the original source is reused.
819   if (!isModelParsingAction())
820     CI.createPreprocessor(getTranslationUnitKind());
821 
822   // Inform the diagnostic client we are processing a source file.
823   CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
824                                            &CI.getPreprocessor());
825   HasBegunSourceFile = true;
826 
827   // Handle C++20 header units.
828   // Here, the user has the option to specify that the header name should be
829   // looked up in the pre-processor search paths (and the main filename as
830   // passed by the driver might therefore be incomplete until that look-up).
831   if (CI.getLangOpts().CPlusPlusModules && Input.getKind().isHeaderUnit() &&
832       !Input.getKind().isPreprocessed()) {
833     StringRef FileName = Input.getFile();
834     InputKind Kind = Input.getKind();
835     if (Kind.getHeaderUnitKind() != InputKind::HeaderUnit_Abs) {
836       assert(CI.hasPreprocessor() &&
837              "trying to build a header unit without a Pre-processor?");
838       HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
839       // Relative searches begin from CWD.
840       auto Dir = CI.getFileManager().getOptionalDirectoryRef(".");
841       SmallVector<std::pair<OptionalFileEntryRef, DirectoryEntryRef>, 1> CWD;
842       CWD.push_back({std::nullopt, *Dir});
843       OptionalFileEntryRef FE =
844           HS.LookupFile(FileName, SourceLocation(),
845                         /*Angled*/ Input.getKind().getHeaderUnitKind() ==
846                             InputKind::HeaderUnit_System,
847                         nullptr, nullptr, CWD, nullptr, nullptr, nullptr,
848                         nullptr, nullptr, nullptr);
849       if (!FE) {
850         CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
851             << FileName;
852         return false;
853       }
854       // We now have the filename...
855       FileName = FE->getName();
856       // ... still a header unit, but now use the path as written.
857       Kind = Input.getKind().withHeaderUnit(InputKind::HeaderUnit_Abs);
858       Input = FrontendInputFile(FileName, Kind, Input.isSystem());
859     }
860     // Unless the user has overridden the name, the header unit module name is
861     // the pathname for the file.
862     if (CI.getLangOpts().ModuleName.empty())
863       CI.getLangOpts().ModuleName = std::string(FileName);
864     CI.getLangOpts().CurrentModule = CI.getLangOpts().ModuleName;
865   }
866 
867   if (!CI.InitializeSourceManager(Input))
868     return false;
869 
870   if (CI.getLangOpts().CPlusPlusModules && Input.getKind().isHeaderUnit() &&
871       Input.getKind().isPreprocessed() && !usesPreprocessorOnly()) {
872     // We have an input filename like foo.iih, but we want to find the right
873     // module name (and original file, to build the map entry).
874     // Check if the first line specifies the original source file name with a
875     // linemarker.
876     std::string PresumedInputFile = std::string(getCurrentFileOrBufferName());
877     ReadOriginalFileName(CI, PresumedInputFile);
878     // Unless the user overrides this, the module name is the name by which the
879     // original file was known.
880     if (CI.getLangOpts().ModuleName.empty())
881       CI.getLangOpts().ModuleName = std::string(PresumedInputFile);
882     CI.getLangOpts().CurrentModule = CI.getLangOpts().ModuleName;
883   }
884 
885   // For module map files, we first parse the module map and synthesize a
886   // "<module-includes>" buffer before more conventional processing.
887   if (Input.getKind().getFormat() == InputKind::ModuleMap) {
888     CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleMap);
889 
890     std::string PresumedModuleMapFile;
891     unsigned OffsetToContents;
892     if (loadModuleMapForModuleBuild(CI, Input.isSystem(),
893                                     Input.isPreprocessed(),
894                                     PresumedModuleMapFile, OffsetToContents))
895       return false;
896 
897     auto *CurrentModule = prepareToBuildModule(CI, Input.getFile());
898     if (!CurrentModule)
899       return false;
900 
901     CurrentModule->PresumedModuleMapFile = PresumedModuleMapFile;
902 
903     if (OffsetToContents)
904       // If the module contents are in the same file, skip to them.
905       CI.getPreprocessor().setSkipMainFilePreamble(OffsetToContents, true);
906     else {
907       // Otherwise, convert the module description to a suitable input buffer.
908       auto Buffer = getInputBufferForModule(CI, CurrentModule);
909       if (!Buffer)
910         return false;
911 
912       // Reinitialize the main file entry to refer to the new input.
913       auto Kind = CurrentModule->IsSystem ? SrcMgr::C_System : SrcMgr::C_User;
914       auto &SourceMgr = CI.getSourceManager();
915       auto BufferID = SourceMgr.createFileID(std::move(Buffer), Kind);
916       assert(BufferID.isValid() && "couldn't create module buffer ID");
917       SourceMgr.setMainFileID(BufferID);
918     }
919   }
920 
921   // Initialize the action.
922   if (!BeginSourceFileAction(CI))
923     return false;
924 
925   // If we were asked to load any module map files, do so now.
926   for (const auto &Filename : CI.getFrontendOpts().ModuleMapFiles) {
927     if (auto File = CI.getFileManager().getOptionalFileRef(Filename))
928       CI.getPreprocessor().getHeaderSearchInfo().loadModuleMapFile(
929           *File, /*IsSystem*/false);
930     else
931       CI.getDiagnostics().Report(diag::err_module_map_not_found) << Filename;
932   }
933 
934   // If compiling implementation of a module, load its module map file now.
935   (void)CI.getPreprocessor().getCurrentModuleImplementation();
936 
937   // Add a module declaration scope so that modules from -fmodule-map-file
938   // arguments may shadow modules found implicitly in search paths.
939   CI.getPreprocessor()
940       .getHeaderSearchInfo()
941       .getModuleMap()
942       .finishModuleDeclarationScope();
943 
944   // Create the AST context and consumer unless this is a preprocessor only
945   // action.
946   if (!usesPreprocessorOnly()) {
947     // Parsing a model file should reuse the existing ASTContext.
948     if (!isModelParsingAction())
949       CI.createASTContext();
950 
951     // For preprocessed files, check if the first line specifies the original
952     // source file name with a linemarker.
953     std::string PresumedInputFile = std::string(getCurrentFileOrBufferName());
954     if (Input.isPreprocessed())
955       ReadOriginalFileName(CI, PresumedInputFile);
956 
957     std::unique_ptr<ASTConsumer> Consumer =
958         CreateWrappedASTConsumer(CI, PresumedInputFile);
959     if (!Consumer)
960       return false;
961 
962     // FIXME: should not overwrite ASTMutationListener when parsing model files?
963     if (!isModelParsingAction())
964       CI.getASTContext().setASTMutationListener(Consumer->GetASTMutationListener());
965 
966     if (!CI.getPreprocessorOpts().ChainedIncludes.empty()) {
967       // Convert headers to PCH and chain them.
968       IntrusiveRefCntPtr<ExternalSemaSource> source, FinalReader;
969       source = createChainedIncludesSource(CI, FinalReader);
970       if (!source)
971         return false;
972       CI.setASTReader(static_cast<ASTReader *>(FinalReader.get()));
973       CI.getASTContext().setExternalSource(source);
974     } else if (CI.getLangOpts().Modules ||
975                !CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
976       // Use PCM or PCH.
977       assert(hasPCHSupport() && "This action does not have PCH support!");
978       ASTDeserializationListener *DeserialListener =
979           Consumer->GetASTDeserializationListener();
980       bool DeleteDeserialListener = false;
981       if (CI.getPreprocessorOpts().DumpDeserializedPCHDecls) {
982         DeserialListener = new DeserializedDeclsDumper(DeserialListener,
983                                                        DeleteDeserialListener);
984         DeleteDeserialListener = true;
985       }
986       if (!CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn.empty()) {
987         DeserialListener = new DeserializedDeclsChecker(
988             CI.getASTContext(),
989             CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn,
990             DeserialListener, DeleteDeserialListener);
991         DeleteDeserialListener = true;
992       }
993       if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
994         CI.createPCHExternalASTSource(
995             CI.getPreprocessorOpts().ImplicitPCHInclude,
996             CI.getPreprocessorOpts().DisablePCHOrModuleValidation,
997             CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
998             DeserialListener, DeleteDeserialListener);
999         if (!CI.getASTContext().getExternalSource())
1000           return false;
1001       }
1002       // If modules are enabled, create the AST reader before creating
1003       // any builtins, so that all declarations know that they might be
1004       // extended by an external source.
1005       if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
1006           !CI.getASTContext().getExternalSource()) {
1007         CI.createASTReader();
1008         CI.getASTReader()->setDeserializationListener(DeserialListener,
1009                                                       DeleteDeserialListener);
1010       }
1011     }
1012 
1013     CI.setASTConsumer(std::move(Consumer));
1014     if (!CI.hasASTConsumer())
1015       return false;
1016   }
1017 
1018   // Initialize built-in info as long as we aren't using an external AST
1019   // source.
1020   if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
1021       !CI.getASTContext().getExternalSource()) {
1022     Preprocessor &PP = CI.getPreprocessor();
1023     PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
1024                                            PP.getLangOpts());
1025   } else {
1026     // FIXME: If this is a problem, recover from it by creating a multiplex
1027     // source.
1028     assert((!CI.getLangOpts().Modules || CI.getASTReader()) &&
1029            "modules enabled but created an external source that "
1030            "doesn't support modules");
1031   }
1032 
1033   // If we were asked to load any module files, do so now.
1034   for (const auto &ModuleFile : CI.getFrontendOpts().ModuleFiles) {
1035     serialization::ModuleFile *Loaded = nullptr;
1036     if (!CI.loadModuleFile(ModuleFile, Loaded))
1037       return false;
1038 
1039     if (Loaded && Loaded->StandardCXXModule)
1040       CI.getDiagnostics().Report(
1041           diag::warn_eagerly_load_for_standard_cplusplus_modules);
1042   }
1043 
1044   // If there is a layout overrides file, attach an external AST source that
1045   // provides the layouts from that file.
1046   if (!CI.getFrontendOpts().OverrideRecordLayoutsFile.empty() &&
1047       CI.hasASTContext() && !CI.getASTContext().getExternalSource()) {
1048     IntrusiveRefCntPtr<ExternalASTSource>
1049       Override(new LayoutOverrideSource(
1050                      CI.getFrontendOpts().OverrideRecordLayoutsFile));
1051     CI.getASTContext().setExternalSource(Override);
1052   }
1053 
1054   // Setup HLSL External Sema Source
1055   if (CI.getLangOpts().HLSL && CI.hasASTContext()) {
1056     IntrusiveRefCntPtr<ExternalSemaSource> HLSLSema(
1057         new HLSLExternalSemaSource());
1058     if (auto *SemaSource = dyn_cast_if_present<ExternalSemaSource>(
1059             CI.getASTContext().getExternalSource())) {
1060       IntrusiveRefCntPtr<ExternalSemaSource> MultiSema(
1061           new MultiplexExternalSemaSource(SemaSource, HLSLSema.get()));
1062       CI.getASTContext().setExternalSource(MultiSema);
1063     } else
1064       CI.getASTContext().setExternalSource(HLSLSema);
1065   }
1066 
1067   FailureCleanup.release();
1068   return true;
1069 }
1070 
Execute()1071 llvm::Error FrontendAction::Execute() {
1072   CompilerInstance &CI = getCompilerInstance();
1073 
1074   if (CI.hasFrontendTimer()) {
1075     llvm::TimeRegion Timer(CI.getFrontendTimer());
1076     ExecuteAction();
1077   }
1078   else ExecuteAction();
1079 
1080   // If we are supposed to rebuild the global module index, do so now unless
1081   // there were any module-build failures.
1082   if (CI.shouldBuildGlobalModuleIndex() && CI.hasFileManager() &&
1083       CI.hasPreprocessor()) {
1084     StringRef Cache =
1085         CI.getPreprocessor().getHeaderSearchInfo().getModuleCachePath();
1086     if (!Cache.empty()) {
1087       if (llvm::Error Err = GlobalModuleIndex::writeIndex(
1088               CI.getFileManager(), CI.getPCHContainerReader(), Cache)) {
1089         // FIXME this drops the error on the floor, but
1090         // Index/pch-from-libclang.c seems to rely on dropping at least some of
1091         // the error conditions!
1092         consumeError(std::move(Err));
1093       }
1094     }
1095   }
1096 
1097   return llvm::Error::success();
1098 }
1099 
EndSourceFile()1100 void FrontendAction::EndSourceFile() {
1101   CompilerInstance &CI = getCompilerInstance();
1102 
1103   // Inform the diagnostic client we are done with this source file.
1104   CI.getDiagnosticClient().EndSourceFile();
1105 
1106   // Inform the preprocessor we are done.
1107   if (CI.hasPreprocessor())
1108     CI.getPreprocessor().EndSourceFile();
1109 
1110   // Finalize the action.
1111   EndSourceFileAction();
1112 
1113   // Sema references the ast consumer, so reset sema first.
1114   //
1115   // FIXME: There is more per-file stuff we could just drop here?
1116   bool DisableFree = CI.getFrontendOpts().DisableFree;
1117   if (DisableFree) {
1118     CI.resetAndLeakSema();
1119     CI.resetAndLeakASTContext();
1120     llvm::BuryPointer(CI.takeASTConsumer().get());
1121   } else {
1122     CI.setSema(nullptr);
1123     CI.setASTContext(nullptr);
1124     CI.setASTConsumer(nullptr);
1125   }
1126 
1127   if (CI.getFrontendOpts().ShowStats) {
1128     llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFileOrBufferName() << "':\n";
1129     CI.getPreprocessor().PrintStats();
1130     CI.getPreprocessor().getIdentifierTable().PrintStats();
1131     CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
1132     CI.getSourceManager().PrintStats();
1133     llvm::errs() << "\n";
1134   }
1135 
1136   // Cleanup the output streams, and erase the output files if instructed by the
1137   // FrontendAction.
1138   CI.clearOutputFiles(/*EraseFiles=*/shouldEraseOutputFiles());
1139 
1140   // The resources are owned by AST when the current file is AST.
1141   // So we reset the resources here to avoid users accessing it
1142   // accidently.
1143   if (isCurrentFileAST()) {
1144     if (DisableFree) {
1145       CI.resetAndLeakPreprocessor();
1146       CI.resetAndLeakSourceManager();
1147       CI.resetAndLeakFileManager();
1148       llvm::BuryPointer(std::move(CurrentASTUnit));
1149     } else {
1150       CI.setPreprocessor(nullptr);
1151       CI.setSourceManager(nullptr);
1152       CI.setFileManager(nullptr);
1153     }
1154   }
1155 
1156   setCompilerInstance(nullptr);
1157   setCurrentInput(FrontendInputFile());
1158   CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
1159 }
1160 
shouldEraseOutputFiles()1161 bool FrontendAction::shouldEraseOutputFiles() {
1162   return getCompilerInstance().getDiagnostics().hasErrorOccurred();
1163 }
1164 
1165 //===----------------------------------------------------------------------===//
1166 // Utility Actions
1167 //===----------------------------------------------------------------------===//
1168 
ExecuteAction()1169 void ASTFrontendAction::ExecuteAction() {
1170   CompilerInstance &CI = getCompilerInstance();
1171   if (!CI.hasPreprocessor())
1172     return;
1173   // This is a fallback: If the client forgets to invoke this, we mark the
1174   // current stack as the bottom. Though not optimal, this could help prevent
1175   // stack overflow during deep recursion.
1176   clang::noteBottomOfStack();
1177 
1178   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
1179   // here so the source manager would be initialized.
1180   if (hasCodeCompletionSupport() &&
1181       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
1182     CI.createCodeCompletionConsumer();
1183 
1184   // Use a code completion consumer?
1185   CodeCompleteConsumer *CompletionConsumer = nullptr;
1186   if (CI.hasCodeCompletionConsumer())
1187     CompletionConsumer = &CI.getCodeCompletionConsumer();
1188 
1189   if (!CI.hasSema())
1190     CI.createSema(getTranslationUnitKind(), CompletionConsumer);
1191 
1192   ParseAST(CI.getSema(), CI.getFrontendOpts().ShowStats,
1193            CI.getFrontendOpts().SkipFunctionBodies);
1194 }
1195 
anchor()1196 void PluginASTAction::anchor() { }
1197 
1198 std::unique_ptr<ASTConsumer>
CreateASTConsumer(CompilerInstance & CI,StringRef InFile)1199 PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
1200                                               StringRef InFile) {
1201   llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
1202 }
1203 
PrepareToExecuteAction(CompilerInstance & CI)1204 bool WrapperFrontendAction::PrepareToExecuteAction(CompilerInstance &CI) {
1205   return WrappedAction->PrepareToExecuteAction(CI);
1206 }
1207 std::unique_ptr<ASTConsumer>
CreateASTConsumer(CompilerInstance & CI,StringRef InFile)1208 WrapperFrontendAction::CreateASTConsumer(CompilerInstance &CI,
1209                                          StringRef InFile) {
1210   return WrappedAction->CreateASTConsumer(CI, InFile);
1211 }
BeginInvocation(CompilerInstance & CI)1212 bool WrapperFrontendAction::BeginInvocation(CompilerInstance &CI) {
1213   return WrappedAction->BeginInvocation(CI);
1214 }
BeginSourceFileAction(CompilerInstance & CI)1215 bool WrapperFrontendAction::BeginSourceFileAction(CompilerInstance &CI) {
1216   WrappedAction->setCurrentInput(getCurrentInput());
1217   WrappedAction->setCompilerInstance(&CI);
1218   auto Ret = WrappedAction->BeginSourceFileAction(CI);
1219   // BeginSourceFileAction may change CurrentInput, e.g. during module builds.
1220   setCurrentInput(WrappedAction->getCurrentInput());
1221   return Ret;
1222 }
ExecuteAction()1223 void WrapperFrontendAction::ExecuteAction() {
1224   WrappedAction->ExecuteAction();
1225 }
EndSourceFile()1226 void WrapperFrontendAction::EndSourceFile() { WrappedAction->EndSourceFile(); }
EndSourceFileAction()1227 void WrapperFrontendAction::EndSourceFileAction() {
1228   WrappedAction->EndSourceFileAction();
1229 }
shouldEraseOutputFiles()1230 bool WrapperFrontendAction::shouldEraseOutputFiles() {
1231   return WrappedAction->shouldEraseOutputFiles();
1232 }
1233 
usesPreprocessorOnly() const1234 bool WrapperFrontendAction::usesPreprocessorOnly() const {
1235   return WrappedAction->usesPreprocessorOnly();
1236 }
getTranslationUnitKind()1237 TranslationUnitKind WrapperFrontendAction::getTranslationUnitKind() {
1238   return WrappedAction->getTranslationUnitKind();
1239 }
hasPCHSupport() const1240 bool WrapperFrontendAction::hasPCHSupport() const {
1241   return WrappedAction->hasPCHSupport();
1242 }
hasASTFileSupport() const1243 bool WrapperFrontendAction::hasASTFileSupport() const {
1244   return WrappedAction->hasASTFileSupport();
1245 }
hasIRSupport() const1246 bool WrapperFrontendAction::hasIRSupport() const {
1247   return WrappedAction->hasIRSupport();
1248 }
hasCodeCompletionSupport() const1249 bool WrapperFrontendAction::hasCodeCompletionSupport() const {
1250   return WrappedAction->hasCodeCompletionSupport();
1251 }
1252 
WrapperFrontendAction(std::unique_ptr<FrontendAction> WrappedAction)1253 WrapperFrontendAction::WrapperFrontendAction(
1254     std::unique_ptr<FrontendAction> WrappedAction)
1255   : WrappedAction(std::move(WrappedAction)) {}
1256