C++ ModuleDecl类代码示例

ModuleInfo* XQueryCompiler::parseInfo(
    std::istream& aXQuery,
    const zstring& aFileName)
{
  parsenode_t lParseNode = parse(aXQuery, aFileName);

  if (typeid (*lParseNode) == typeid (ParseErrorNode))
  {
    ParseErrorNode* pen = static_cast<ParseErrorNode *>(lParseNode.getp());
    throw XQUERY_EXCEPTION_VAR(pen->err, 
    ERROR_PARAMS(pen->msg), ERROR_LOC(pen->get_location()));
  }

  LibraryModule* lLibModule = dynamic_cast<LibraryModule*>(lParseNode.getp());

  zstring lTargetNamespace;

  if (lLibModule)
  {
    ModuleDecl* lDecl = lLibModule->get_decl().getp();
    lTargetNamespace = lDecl->get_target_namespace();
  }

  return new ModuleInfoImpl(lTargetNamespace);
}

SILLinkage
swift::getLinkageForProtocolConformance(const NormalProtocolConformance *C,
                                        ForDefinition_t definition) {
  // Behavior conformances are always private.
  if (C->isBehaviorConformance())
    return (definition ? SILLinkage::Private : SILLinkage::PrivateExternal);

  ModuleDecl *conformanceModule = C->getDeclContext()->getParentModule();

  // If the conformance was synthesized by the ClangImporter, give it
  // shared linkage.
  auto typeDecl = C->getType()->getNominalOrBoundGenericNominal();
  auto typeUnit = typeDecl->getModuleScopeContext();
  if (isa<ClangModuleUnit>(typeUnit)
      && conformanceModule == typeUnit->getParentModule())
    return SILLinkage::Shared;

  // If we're bulding with -sil-serialize-all, give the conformance public
  // linkage.
  if (conformanceModule->getResilienceStrategy()
      == ResilienceStrategy::Fragile)
    return (definition ? SILLinkage::Public : SILLinkage::PublicExternal);

  // FIXME: This should be using std::min(protocol's access, type's access).
  switch (C->getProtocol()->getEffectiveAccess()) {
    case Accessibility::Private:
      return (definition ? SILLinkage::Private : SILLinkage::PrivateExternal);

    case Accessibility::Internal:
      return (definition ? SILLinkage::Hidden : SILLinkage::HiddenExternal);

    default:
      return (definition ? SILLinkage::Public : SILLinkage::PublicExternal);
  }
}

/// Returns true if the object file generated by \p IGM will be the "first"
/// object file in the module. This lets us determine where to put a symbol
/// that must be unique.
static bool isFirstObjectFileInModule(IRGenModule &IGM) {
  if (IGM.getSILModule().isWholeModule())
    return IGM.IRGen.getPrimaryIGM() == &IGM;

  const DeclContext *DC = IGM.getSILModule().getAssociatedContext();
  if (!DC)
    return false;

  assert(!isa<ModuleDecl>(DC) && "that would be a whole module build");
  assert(isa<FileUnit>(DC) && "compiling something smaller than a file?");
  ModuleDecl *containingModule = cast<FileUnit>(DC)->getParentModule();
  return containingModule->getFiles().front() == DC;
}

bool CompilerInstance::loadStdlib() {
  SharedTimer timer("performSema-loadStdlib");
  ModuleDecl *M = Context->getStdlibModule(true);

  if (!M) {
    Diagnostics.diagnose(SourceLoc(), diag::error_stdlib_not_found,
                         Invocation.getTargetTriple());
    return false;
  }

  // If we failed to load, we should have already diagnosed
  if (M->failedToLoad()) {
    assert(Diagnostics.hadAnyError() &&
           "Module failed to load but nothing was diagnosed?");
    return false;
  }
  return true;
}

static void indexModule(llvm::MemoryBuffer *Input,
                        StringRef ModuleName,
                        StringRef Hash,
                        IndexingConsumer &IdxConsumer,
                        CompilerInstance &CI,
                        ArrayRef<const char *> Args) {
  ASTContext &Ctx = CI.getASTContext();
  std::unique_ptr<SerializedModuleLoader> Loader;
  ModuleDecl *Mod = nullptr;
  if (ModuleName == Ctx.StdlibModuleName.str()) {
    Mod = Ctx.getModule({ {Ctx.StdlibModuleName, SourceLoc()} });
  } else {
    Loader = SerializedModuleLoader::create(Ctx);
    auto Buf = std::unique_ptr<llvm::MemoryBuffer>(
        llvm::MemoryBuffer::getMemBuffer(Input->getBuffer(),
                                         Input->getBufferIdentifier()));

    // FIXME: These APIs allocate memory on the ASTContext, meaning it may not
    // be freed for a long time.
    Mod = ModuleDecl::create(Ctx.getIdentifier(ModuleName), Ctx);
    // Indexing is not using documentation now, so don't open the module
    // documentation file.
    // FIXME: refactor the frontend to provide an easy way to figure out the
    // correct filename here.
    auto FUnit = Loader->loadAST(*Mod, None, std::move(Buf), nullptr);

    // FIXME: Not knowing what went wrong is pretty bad. loadModule() should be
    // more modular, rather than emitting diagnostics itself.
    if (!FUnit) {
      IdxConsumer.failed("failed to load module");
      return;
    }

    Mod->setHasResolvedImports();
  }

  // Setup a typechecker for protocol conformance resolving.
  (void)createTypeChecker(Ctx);

  SKIndexDataConsumer IdxDataConsumer(IdxConsumer);
  index::indexModule(Mod, Hash, IdxDataConsumer);
}

void CompilerInstance::performParseOnly(bool EvaluateConditionals) {
  const InputFileKind Kind = Invocation.getInputKind();
  ModuleDecl *MainModule = getMainModule();
  Context->LoadedModules[MainModule->getName()] = MainModule;
  bool KeepTokens = Invocation.getLangOptions().KeepTokensInSourceFile;

  assert((Kind == InputFileKind::IFK_Swift ||
          Kind == InputFileKind::IFK_Swift_Library) &&
         "only supports parsing .swift files");
  (void)Kind;

  auto implicitModuleImportKind = SourceFile::ImplicitModuleImportKind::None;

  // Make sure the main file is the first file in the module but parse it last,
  // to match the parsing logic used when performing Sema.
  if (MainBufferID != NO_SUCH_BUFFER) {
    assert(Kind == InputFileKind::IFK_Swift);
    SourceMgr.setHashbangBufferID(MainBufferID);

    auto *MainFile = new (*Context)
        SourceFile(*MainModule, Invocation.getSourceFileKind(), MainBufferID,
                   implicitModuleImportKind, KeepTokens);
    MainModule->addFile(*MainFile);

    if (MainBufferID == PrimaryBufferID)
      setPrimarySourceFile(MainFile);
  }

  PersistentParserState PersistentState;
  PersistentState.PerformConditionEvaluation = EvaluateConditionals;
  // Parse all the library files.
  for (auto BufferID : InputSourceCodeBufferIDs) {
    if (BufferID == MainBufferID)
      continue;

    auto *NextInput = new (*Context)
        SourceFile(*MainModule, SourceFileKind::Library, BufferID,
                   implicitModuleImportKind, KeepTokens);
    MainModule->addFile(*NextInput);
    if (BufferID == PrimaryBufferID)
      setPrimarySourceFile(NextInput);

    bool Done;
    do {
      // Parser may stop at some erroneous constructions like #else, #endif
      // or '}' in some cases, continue parsing until we are done
      parseIntoSourceFile(*NextInput, BufferID, &Done, nullptr,
                          &PersistentState, nullptr);
    } while (!Done);
  }

  // Now parse the main file.
  if (MainBufferID != NO_SUCH_BUFFER) {
    SourceFile &MainFile =
        MainModule->getMainSourceFile(Invocation.getSourceFileKind());

    bool Done;
    do {
      parseIntoSourceFile(MainFile, MainFile.getBufferID().getValue(), &Done,
                          nullptr, &PersistentState, nullptr);
    } while (!Done);
  }

  assert(Context->LoadedModules.size() == 1 &&
         "Loaded a module during parse-only");
}

void SILGenFunction::emitArtificialTopLevel(ClassDecl *mainClass) {
  // Load argc and argv from the entry point arguments.
  SILValue argc = F.begin()->getArgument(0);
  SILValue argv = F.begin()->getArgument(1);

  switch (mainClass->getArtificialMainKind()) {
  case ArtificialMainKind::UIApplicationMain: {
    // Emit a UIKit main.
    // return UIApplicationMain(C_ARGC, C_ARGV, nil, ClassName);

    CanType NSStringTy = SGM.Types.getNSStringType();
    CanType OptNSStringTy
      = OptionalType::get(NSStringTy)->getCanonicalType();
    CanType IUOptNSStringTy
      = ImplicitlyUnwrappedOptionalType::get(NSStringTy)->getCanonicalType();

    // Look up UIApplicationMain.
    // FIXME: Doing an AST lookup here is gross and not entirely sound;
    // we're getting away with it because the types are guaranteed to already
    // be imported.
    ASTContext &ctx = getASTContext();
    ModuleDecl *UIKit = ctx.getLoadedModule(ctx.getIdentifier("UIKit"));
    SmallVector<ValueDecl *, 1> results;
    UIKit->lookupQualified(UIKit->getInterfaceType(),
                           ctx.getIdentifier("UIApplicationMain"),
                           NL_QualifiedDefault,
                           /*resolver*/nullptr,
                           results);
    assert(!results.empty() && "couldn't find UIApplicationMain in UIKit");
    assert(results.size() == 1 && "more than one UIApplicationMain?");

    SILDeclRef mainRef{results.front(), ResilienceExpansion::Minimal,
                       SILDeclRef::ConstructAtNaturalUncurryLevel,
                       /*isForeign*/true};
    auto UIApplicationMainFn = SGM.M.getOrCreateFunction(mainClass, mainRef,
                                                         NotForDefinition);
    auto fnTy = UIApplicationMainFn->getLoweredFunctionType();
    SILFunctionConventions fnConv(fnTy, SGM.M);

    // Get the class name as a string using NSStringFromClass.
    CanType mainClassTy = mainClass->getDeclaredInterfaceType()
        ->getCanonicalType();
    CanType mainClassMetaty = CanMetatypeType::get(mainClassTy,
                                                   MetatypeRepresentation::ObjC);
    ProtocolDecl *anyObjectProtocol =
      ctx.getProtocol(KnownProtocolKind::AnyObject);
    auto mainClassAnyObjectConformance = ProtocolConformanceRef(
      *SGM.M.getSwiftModule()->lookupConformance(mainClassTy, anyObjectProtocol,
                                                nullptr));
    CanType anyObjectTy = anyObjectProtocol
      ->getDeclaredInterfaceType()
      ->getCanonicalType();
    CanType anyObjectMetaTy = CanExistentialMetatypeType::get(anyObjectTy,
                                                  MetatypeRepresentation::ObjC);

    auto NSStringFromClassType = SILFunctionType::get(nullptr,
                  SILFunctionType::ExtInfo()
                    .withRepresentation(SILFunctionType::Representation::
                                        CFunctionPointer),
                  ParameterConvention::Direct_Unowned,
                  SILParameterInfo(anyObjectMetaTy,
                                   ParameterConvention::Direct_Unowned),
                  SILResultInfo(OptNSStringTy,
                                ResultConvention::Autoreleased),
                  /*error result*/ None,
                  ctx);
    auto NSStringFromClassFn
      = SGM.M.getOrCreateFunction(mainClass, "NSStringFromClass",
                                  SILLinkage::PublicExternal,
                                  NSStringFromClassType,
                                  IsBare, IsTransparent, IsNotSerialized);
    auto NSStringFromClass = B.createFunctionRef(mainClass, NSStringFromClassFn);
    SILValue metaTy = B.createMetatype(mainClass,
                             SILType::getPrimitiveObjectType(mainClassMetaty));
    metaTy = B.createInitExistentialMetatype(mainClass, metaTy,
                          SILType::getPrimitiveObjectType(anyObjectMetaTy),
                          ctx.AllocateCopy(
                            llvm::makeArrayRef(mainClassAnyObjectConformance)));
    SILValue optName = B.createApply(mainClass,
                               NSStringFromClass,
                               NSStringFromClass->getType(),
                               SILType::getPrimitiveObjectType(OptNSStringTy),
                               {}, metaTy);

    // Fix up the string parameters to have the right type.
    SILType nameArgTy = fnConv.getSILArgumentType(3);
    assert(nameArgTy == fnConv.getSILArgumentType(2));
    auto managedName = ManagedValue::forUnmanaged(optName);
    SILValue nilValue;
    if (optName->getType() == nameArgTy) {
      nilValue = getOptionalNoneValue(mainClass,
                                      getTypeLowering(OptNSStringTy));
    } else {
      assert(nameArgTy.getSwiftRValueType() == IUOptNSStringTy);
      nilValue = getOptionalNoneValue(mainClass,
                                      getTypeLowering(IUOptNSStringTy));
      managedName = emitOptionalToOptional(
          mainClass, managedName,
          SILType::getPrimitiveObjectType(IUOptNSStringTy),
          [](SILGenFunction &, SILLocation, ManagedValue input, SILType) {
//.........这里部分代码省略.........

// Returns the callee of an apply_inst if it is basically inlinable.
SILFunction *swift::getEligibleFunction(FullApplySite AI,
                                        InlineSelection WhatToInline) {
  SILFunction *Callee = AI.getReferencedFunction();

  if (!Callee) {
    return nullptr;
  }

  // Not all apply sites can be inlined, even if they're direct.
  if (!SILInliner::canInline(AI))
    return nullptr;

  ModuleDecl *SwiftModule = Callee->getModule().getSwiftModule();
  bool IsInStdlib = (SwiftModule->isStdlibModule() ||
                     SwiftModule->isOnoneSupportModule());

  // Don't inline functions that are marked with the @_semantics or @_effects
  // attribute if the inliner is asked not to inline them.
  if (Callee->hasSemanticsAttrs() || Callee->hasEffectsKind()) {
    if (WhatToInline == InlineSelection::NoSemanticsAndGlobalInit) {
      if (shouldSkipApplyDuringEarlyInlining(AI))
        return nullptr;
      if (Callee->hasSemanticsAttr("inline_late"))
        return nullptr;
    }
    // The "availability" semantics attribute is treated like global-init.
    if (Callee->hasSemanticsAttrs() &&
        WhatToInline != InlineSelection::Everything &&
        (Callee->hasSemanticsAttrThatStartsWith("availability") ||
         (Callee->hasSemanticsAttrThatStartsWith("inline_late")))) {
      return nullptr;
    }
    if (Callee->hasSemanticsAttrs() &&
        WhatToInline == InlineSelection::Everything) {
      if (Callee->hasSemanticsAttrThatStartsWith("inline_late") && IsInStdlib) {
        return nullptr;
      }
    }

  } else if (Callee->isGlobalInit()) {
    if (WhatToInline != InlineSelection::Everything) {
      return nullptr;
    }
  }

  // We can't inline external declarations.
  if (Callee->empty() || Callee->isExternalDeclaration()) {
    return nullptr;
  }

  // Explicitly disabled inlining.
  if (Callee->getInlineStrategy() == NoInline) {
    return nullptr;
  }

  if (!Callee->shouldOptimize()) {
    return nullptr;
  }

  SILFunction *Caller = AI.getFunction();

  // We don't support inlining a function that binds dynamic self because we
  // have no mechanism to preserve the original function's local self metadata.
  if (mayBindDynamicSelf(Callee)) {
    // Check if passed Self is the same as the Self of the caller.
    // In this case, it is safe to inline because both functions
    // use the same Self.
    if (AI.hasSelfArgument() && Caller->hasSelfParam()) {
      auto CalleeSelf = stripCasts(AI.getSelfArgument());
      auto CallerSelf = Caller->getSelfArgument();
      if (CalleeSelf != SILValue(CallerSelf))
        return nullptr;
    } else
      return nullptr;
  }

  // Detect self-recursive calls.
  if (Caller == Callee) {
    return nullptr;
  }

  // A non-fragile function may not be inlined into a fragile function.
  if (Caller->isSerialized() &&
      !Callee->hasValidLinkageForFragileInline()) {
    if (!Callee->hasValidLinkageForFragileRef()) {
      llvm::errs() << "caller: " << Caller->getName() << "\n";
      llvm::errs() << "callee: " << Callee->getName() << "\n";
      llvm_unreachable("Should never be inlining a resilient function into "
                       "a fragile function");
    }
    return nullptr;
  }

  // Inlining self-recursive functions into other functions can result
  // in excessive code duplication since we run the inliner multiple
  // times in our pipeline
  if (calleeIsSelfRecursive(Callee)) {
    return nullptr;
  }
//.........这里部分代码省略.........

void CompilerInstance::performSema() {
  const FrontendOptions &options = Invocation.getFrontendOptions();
  const InputFileKind Kind = Invocation.getInputKind();
  Module *MainModule = getMainModule();
  Context->LoadedModules[MainModule->getName()] = MainModule;

  auto modImpKind = SourceFile::ImplicitModuleImportKind::Stdlib;

  if (Kind == InputFileKind::IFK_SIL) {
    assert(BufferIDs.size() == 1);
    assert(MainBufferID != NO_SUCH_BUFFER);
    // Assume WMO, if a -primary-file option was not provided.
    createSILModule(!options.PrimaryInput.hasValue());
    modImpKind = SourceFile::ImplicitModuleImportKind::None;
  } else if (Invocation.getParseStdlib()) {
    modImpKind = SourceFile::ImplicitModuleImportKind::Builtin;
  }

  switch (modImpKind) {
  case SourceFile::ImplicitModuleImportKind::None:
  case SourceFile::ImplicitModuleImportKind::Builtin:
    break;
  case SourceFile::ImplicitModuleImportKind::Stdlib: {
    ModuleDecl *M = Context->getStdlibModule(true);

    if (!M) {
      Diagnostics.diagnose(SourceLoc(), diag::error_stdlib_not_found,
                           Invocation.getTargetTriple());
      return;
    }

    // If we failed to load, we should have already diagnosed
    if (M->failedToLoad()) {
      assert(Diagnostics.hadAnyError() &&
             "Module failed to load but nothing was diagnosed?");
      return;
    }

    const auto &silOptions = Invocation.getSILOptions();
    if ((silOptions.Optimization <= SILOptions::SILOptMode::None &&
         (options.RequestedAction == FrontendOptions::EmitObject ||
          options.RequestedAction == FrontendOptions::Immediate ||
          options.RequestedAction == FrontendOptions::EmitSIL)) ||
        (silOptions.Optimization == SILOptions::SILOptMode::None &&
         options.RequestedAction >= FrontendOptions::EmitSILGen)) {
      // Implicitly import the SwiftOnoneSupport module in non-optimized
      // builds. This allows for use of popular specialized functions
      // from the standard library, which makes the non-optimized builds
      // execute much faster.
      Invocation.getFrontendOptions()
                .ImplicitImportModuleNames.push_back(SWIFT_ONONE_SUPPORT);
    }
    break;
  }
  }

  auto clangImporter =
    static_cast<ClangImporter *>(Context->getClangModuleLoader());

  Module *underlying = nullptr;
  if (options.ImportUnderlyingModule) {
    underlying = clangImporter->loadModule(SourceLoc(),
                                           std::make_pair(MainModule->getName(),
                                                          SourceLoc()));
    if (!underlying) {
      Diagnostics.diagnose(SourceLoc(), diag::error_underlying_module_not_found,
                           MainModule->getName());
    }
  }

  Module *importedHeaderModule = nullptr;
  StringRef implicitHeaderPath = options.ImplicitObjCHeaderPath;
  if (!implicitHeaderPath.empty()) {
    if (!clangImporter->importBridgingHeader(implicitHeaderPath, MainModule)) {
      importedHeaderModule = clangImporter->getImportedHeaderModule();
      assert(importedHeaderModule);
    }
  }

  SmallVector<Module *, 4> importModules;
  if (!options.ImplicitImportModuleNames.empty()) {
    for (auto &ImplicitImportModuleName : options.ImplicitImportModuleNames) {
      if (Lexer::isIdentifier(ImplicitImportModuleName)) {
        auto moduleID = Context->getIdentifier(ImplicitImportModuleName);
        Module *importModule = Context->getModule(std::make_pair(moduleID,
                                                                 SourceLoc()));
        if (importModule) {
          importModules.push_back(importModule);
        } else {
          Diagnostics.diagnose(SourceLoc(), diag::sema_no_import,
                               ImplicitImportModuleName);
          if (Invocation.getSearchPathOptions().SDKPath.empty() &&
              llvm::Triple(llvm::sys::getProcessTriple()).isMacOSX()) {
            Diagnostics.diagnose(SourceLoc(), diag::sema_no_import_no_sdk);
            Diagnostics.diagnose(SourceLoc(),
                                 diag::sema_no_import_no_sdk_xcrun);
          }
        }
      } else {
        Diagnostics.diagnose(SourceLoc(), diag::error_bad_module_name,
//.........这里部分代码省略.........

bool SourceEntityWalker::walk(ModuleDecl &Mod) {
  SemaAnnotator Annotator(*this);
  return Mod.walk(Annotator);
}

ProtocolConformance *ConformanceLookupTable::getConformance(
                       NominalTypeDecl *nominal,
                       LazyResolver *resolver,
                       ConformanceEntry *entry) {
  // If we already have a conformance, we're done.
  if (auto conformance = entry->getConformance())
    return conformance;

  ProtocolDecl *protocol = entry->getProtocol();

  // Determine where the explicit conformance actually lives.
  // FIXME: This is a hack to ensure that inherited conformances are
  // always "single step", which is bad for resilience but is assumed
  // elsewhere in the compiler.
  DeclContext *conformingDC = getConformingContext(nominal, resolver, entry);
  if (!conformingDC)
    return nullptr;

  auto *conformingNominal =
    conformingDC->getAsNominalTypeOrNominalTypeExtensionContext();

  // Form the conformance.
  Type type = entry->getDeclContext()->getDeclaredTypeInContext();
  ProtocolConformance *conformance;
    ASTContext &ctx = nominal->getASTContext();
  if (entry->getKind() == ConformanceEntryKind::Inherited) {
    // For an inherited conformance, the conforming nominal type will
    // be different from the nominal type.
    assert(conformingNominal != nominal && "Broken inherited conformance");

    // Find the superclass type that matches where the conformance was
    // declared.
    Type superclassTy = type->getSuperclass(resolver);
    while (superclassTy->getAnyNominal() != conformingNominal)
      superclassTy = superclassTy->getSuperclass(resolver);

    // Look up the inherited conformance.
    ModuleDecl *module = entry->getDeclContext()->getParentModule();
    auto inheritedConformance = module->lookupConformance(superclassTy,
                                                          protocol,
                                                          resolver)
                                  .getPointer();

    // Form the inherited conformance.
    conformance = ctx.getInheritedConformance(
                    type,
                    inheritedConformance->getConcrete());
  } else {
    // Create or find the normal conformance.
    Type conformingType = conformingDC->getDeclaredTypeInContext();
    SourceLoc conformanceLoc
      = conformingNominal == conformingDC
          ? conformingNominal->getLoc()
          : cast<ExtensionDecl>(conformingDC)->getLoc();

    conformance = ctx.getConformance(conformingType, protocol, conformanceLoc,
                                     conformingDC,
                                     ProtocolConformanceState::Incomplete);
  }

  // Record the conformance.
  entry->Conformance = conformance;
  return conformance;
}

void SILGenFunction::emitArtificialTopLevel(ClassDecl *mainClass) {
  // Load argc and argv from the entry point arguments.
  SILValue argc = F.begin()->getArgument(0);
  SILValue argv = F.begin()->getArgument(1);

  switch (mainClass->getArtificialMainKind()) {
  case ArtificialMainKind::UIApplicationMain: {
    // Emit a UIKit main.
    // return UIApplicationMain(C_ARGC, C_ARGV, nil, ClassName);

    CanType NSStringTy = SGM.Types.getNSStringType();
    CanType OptNSStringTy
      = OptionalType::get(NSStringTy)->getCanonicalType();

    // Look up UIApplicationMain.
    // FIXME: Doing an AST lookup here is gross and not entirely sound;
    // we're getting away with it because the types are guaranteed to already
    // be imported.
    ASTContext &ctx = getASTContext();
    
    std::pair<Identifier, SourceLoc> UIKitName =
      {ctx.getIdentifier("UIKit"), SourceLoc()};
    
    ModuleDecl *UIKit = ctx
      .getClangModuleLoader()
      ->loadModule(SourceLoc(), UIKitName);
    assert(UIKit && "couldn't find UIKit objc module?!");
    SmallVector<ValueDecl *, 1> results;
    UIKit->lookupQualified(UIKit,
                           ctx.getIdentifier("UIApplicationMain"),
                           NL_QualifiedDefault,
                           results);
    assert(results.size() == 1
           && "couldn't find a unique UIApplicationMain in the UIKit ObjC "
              "module?!");

    ValueDecl *UIApplicationMainDecl = results.front();

    auto mainRef = SILDeclRef(UIApplicationMainDecl).asForeign();
    SILGenFunctionBuilder builder(SGM);
    auto UIApplicationMainFn =
        builder.getOrCreateFunction(mainClass, mainRef, NotForDefinition);
    auto fnTy = UIApplicationMainFn->getLoweredFunctionType();
    SILFunctionConventions fnConv(fnTy, SGM.M);

    // Get the class name as a string using NSStringFromClass.
    CanType mainClassTy = mainClass->getDeclaredInterfaceType()
        ->getCanonicalType();
    CanType mainClassMetaty = CanMetatypeType::get(mainClassTy,
                                                   MetatypeRepresentation::ObjC);
    CanType anyObjectTy = ctx.getAnyObjectType();
    CanType anyObjectMetaTy = CanExistentialMetatypeType::get(anyObjectTy,
                                                  MetatypeRepresentation::ObjC);

    auto NSStringFromClassType = SILFunctionType::get(nullptr,
                  SILFunctionType::ExtInfo()
                    .withRepresentation(SILFunctionType::Representation::
                                        CFunctionPointer),
                  SILCoroutineKind::None,
                  ParameterConvention::Direct_Unowned,
                  SILParameterInfo(anyObjectMetaTy,
                                   ParameterConvention::Direct_Unowned),
                  /*yields*/ {},
                  SILResultInfo(OptNSStringTy,
                                ResultConvention::Autoreleased),
                  /*error result*/ None,
                  ctx);
    auto NSStringFromClassFn = builder.getOrCreateFunction(
        mainClass, "NSStringFromClass", SILLinkage::PublicExternal,
        NSStringFromClassType, IsBare, IsTransparent, IsNotSerialized);
    auto NSStringFromClass = B.createFunctionRef(mainClass, NSStringFromClassFn);
    SILValue metaTy = B.createMetatype(mainClass,
                             SILType::getPrimitiveObjectType(mainClassMetaty));
    metaTy = B.createInitExistentialMetatype(mainClass, metaTy,
                          SILType::getPrimitiveObjectType(anyObjectMetaTy), {});
    SILValue optName = B.createApply(mainClass,
                               NSStringFromClass,
                               NSStringFromClass->getType(),
                               SILType::getPrimitiveObjectType(OptNSStringTy),
                               {}, metaTy);

    // Fix up the string parameters to have the right type.
    SILType nameArgTy = fnConv.getSILArgumentType(3);
    assert(nameArgTy == fnConv.getSILArgumentType(2));
    (void)nameArgTy;
    auto managedName = ManagedValue::forUnmanaged(optName);
    SILValue nilValue;
    assert(optName->getType() == nameArgTy);
    nilValue = getOptionalNoneValue(mainClass,
                                    getTypeLowering(OptNSStringTy));

    // Fix up argv to have the right type.
    auto argvTy = fnConv.getSILArgumentType(1);

    SILType unwrappedTy = argvTy;
    if (Type innerTy = argvTy.getASTType()->getOptionalObjectType()) {
      auto canInnerTy = innerTy->getCanonicalType();
      unwrappedTy = SILType::getPrimitiveObjectType(canInnerTy);
    }

//.........这里部分代码省略.........

void NameBinder::addImport(
    SmallVectorImpl<SourceFile::ImportedModuleDesc> &imports, ImportDecl *ID) {
  if (ID->getModulePath().front().first == SF.getParentModule()->getName() &&
      ID->getModulePath().size() == 1 && !shouldImportSelfImportClang(ID, SF)) {
    // If the imported module name is the same as the current module,
    // produce a diagnostic.
    StringRef filename = llvm::sys::path::filename(SF.getFilename());
    if (filename.empty())
      Context.Diags.diagnose(ID, diag::sema_import_current_module,
                             ID->getModulePath().front().first);
    else
      Context.Diags.diagnose(ID, diag::sema_import_current_module_with_file,
                             filename, ID->getModulePath().front().first);
    ID->setModule(SF.getParentModule());
    return;
  }

  ModuleDecl *M = getModule(ID->getModulePath());
  if (!M) {
    SmallString<64> modulePathStr;
    interleave(ID->getModulePath(),
               [&](ImportDecl::AccessPathElement elem) {
                 modulePathStr += elem.first.str();
               },
               [&] { modulePathStr += "."; });

    auto diagKind = diag::sema_no_import;
    if (SF.Kind == SourceFileKind::REPL || Context.LangOpts.DebuggerSupport)
      diagKind = diag::sema_no_import_repl;
    diagnose(ID->getLoc(), diagKind, modulePathStr);

    if (Context.SearchPathOpts.SDKPath.empty() &&
        llvm::Triple(llvm::sys::getProcessTriple()).isMacOSX()) {
      diagnose(SourceLoc(), diag::sema_no_import_no_sdk);
      diagnose(SourceLoc(), diag::sema_no_import_no_sdk_xcrun);
    }
    return;
  }

  ID->setModule(M);

  ModuleDecl *topLevelModule;
  if (ID->getModulePath().size() == 1) {
    topLevelModule = M;
  } else {
    // If we imported a submodule, import the top-level module as well.
    Identifier topLevelName = ID->getModulePath().front().first;
    topLevelModule = Context.getLoadedModule(topLevelName);
    if (!topLevelModule) {
      // Clang can sometimes import top-level modules as if they were
      // submodules.
      assert(!M->getFiles().empty() &&
             isa<ClangModuleUnit>(M->getFiles().front()));
      topLevelModule = M;
    }
  }

  auto *testableAttr = ID->getAttrs().getAttribute<TestableAttr>();
  if (testableAttr && !topLevelModule->isTestingEnabled() &&
      Context.LangOpts.EnableTestableAttrRequiresTestableModule) {
    diagnose(ID->getModulePath().front().second, diag::module_not_testable,
             topLevelModule->getName());
    testableAttr->setInvalid();
  }

  auto *privateImportAttr = ID->getAttrs().getAttribute<PrivateImportAttr>();
  StringRef privateImportFileName;
  if (privateImportAttr) {
    if (!topLevelModule->arePrivateImportsEnabled()) {
      diagnose(ID->getModulePath().front().second,
               diag::module_not_compiled_for_private_import,
               topLevelModule->getName());
      privateImportAttr->setInvalid();
    } else {
      privateImportFileName = privateImportAttr->getSourceFile();
    }
  }

  ImportOptions options;
  if (ID->isExported())
    options |= SourceFile::ImportFlags::Exported;
  if (testableAttr)
    options |= SourceFile::ImportFlags::Testable;
  if (privateImportAttr)
    options |= SourceFile::ImportFlags::PrivateImport;

  auto *implementationOnlyAttr =
      ID->getAttrs().getAttribute<ImplementationOnlyAttr>();
  if (implementationOnlyAttr) {
    if (options.contains(SourceFile::ImportFlags::Exported)) {
      diagnose(ID, diag::import_implementation_cannot_be_exported,
               topLevelModule->getName())
        .fixItRemove(implementationOnlyAttr->getRangeWithAt());
    } else {
      options |= SourceFile::ImportFlags::ImplementationOnly;
    }
  }

  imports.push_back(SourceFile::ImportedModuleDesc(
      {ID->getDeclPath(), M}, options, privateImportFileName));
//.........这里部分代码省略.........

ImportDepth::ImportDepth(ASTContext &context, CompilerInvocation &invocation) {
  llvm::DenseSet<ModuleDecl *> seen;
  std::deque<std::pair<ModuleDecl *, uint8_t>> worklist;

  StringRef mainModule = invocation.getModuleName();
  auto *main = context.getLoadedModule(context.getIdentifier(mainModule));
  assert(main && "missing main module");
  worklist.emplace_back(main, uint8_t(0));

  // Imports from -import-name such as Playground auxiliary sources are treated
  // specially by applying import depth 0.
  llvm::StringSet<> auxImports;
  for (StringRef moduleName :
       invocation.getFrontendOptions().ImplicitImportModuleNames)
    auxImports.insert(moduleName);

  // Private imports from this module.
  // FIXME: only the private imports from the current source file.
  ModuleDecl::ImportFilter importFilter;
  importFilter |= ModuleDecl::ImportFilterKind::Private;
  importFilter |= ModuleDecl::ImportFilterKind::ImplementationOnly;
  SmallVector<ModuleDecl::ImportedModule, 16> mainImports;
  main->getImportedModules(mainImports, importFilter);
  for (auto &import : mainImports) {
    uint8_t depth = 1;
    if (auxImports.count(import.second->getName().str()))
      depth = 0;
    worklist.emplace_back(import.second, depth);
  }

  // Fill depths with BFS over module imports.
  while (!worklist.empty()) {
    ModuleDecl *module;
    uint8_t depth;
    std::tie(module, depth) = worklist.front();
    worklist.pop_front();

    if (!seen.insert(module).second)
      continue;

    // Insert new module:depth mapping.
    const clang::Module *CM = module->findUnderlyingClangModule();
    if (CM) {
      depths[CM->getFullModuleName()] = depth;
    } else {
      depths[module->getName().str()] = depth;
    }

    // Add imports to the worklist.
    SmallVector<ModuleDecl::ImportedModule, 16> imports;
    module->getImportedModules(imports);
    for (auto &import : imports) {
      uint8_t next = std::max(depth, uint8_t(depth + 1)); // unsigned wrap

      // Implicitly imported sub-modules get the same depth as their parent.
      if (const clang::Module *CMI = import.second->findUnderlyingClangModule())
        if (CM && CMI->isSubModuleOf(CM))
          next = depth;
      worklist.emplace_back(import.second, next);
    }
  }
}

static void addModuleDependencies(ArrayRef<ModuleDecl::ImportedModule> imports,
                                  StringRef indexStorePath,
                                  bool indexSystemModules,
                                  StringRef targetTriple,
                                  const clang::CompilerInstance &clangCI,
                                  DiagnosticEngine &diags,
                                  IndexUnitWriter &unitWriter,
                                  StringScratchSpace &moduleNameScratch) {
  auto &fileMgr = clangCI.getFileManager();

  for (auto &import : imports) {
    ModuleDecl *mod = import.second;
    if (mod->isOnoneSupportModule())
      continue; // ignore the Onone support library.
    if (mod->isSwiftShimsModule())
      continue;

    for (auto *FU : mod->getFiles()) {
      switch (FU->getKind()) {
      case FileUnitKind::Source:
      case FileUnitKind::Builtin:
        break;
      case FileUnitKind::SerializedAST:
      case FileUnitKind::DWARFModule:
      case FileUnitKind::ClangModule: {
        auto *LFU = cast<LoadedFile>(FU);
        if (auto *F = fileMgr.getFile(LFU->getFilename())) {
          std::string moduleName = mod->getNameStr();
          bool withoutUnitName = true;
          if (FU->getKind() == FileUnitKind::ClangModule) {
            withoutUnitName = false;
            auto clangModUnit = cast<ClangModuleUnit>(LFU);
            if (auto clangMod = clangModUnit->getUnderlyingClangModule()) {
              moduleName = clangMod->getTopLevelModuleName();
              // FIXME: clang's -Rremarks do not seem to go through Swift's
              // diagnostic emitter.
              clang::index::emitIndexDataForModuleFile(clangMod,
                                                       clangCI, unitWriter);
            }
          } else {
            // Serialized AST file.
            // Only index system modules (essentially stdlib and overlays).
            // We don't officially support binary swift modules, so normally
            // the index data for user modules would get generated while
            // building them.
            if (mod->isSystemModule() && indexSystemModules) {
              emitDataForSwiftSerializedModule(mod, indexStorePath,
                                               indexSystemModules,
                                               targetTriple, clangCI, diags,
                                               unitWriter);
              withoutUnitName = false;
            }
          }
          clang::index::writer::OpaqueModule opaqMod =
              moduleNameScratch.createString(moduleName);
          unitWriter.addASTFileDependency(F, mod->isSystemModule(), opaqMod,
                                          withoutUnitName);
        }
        break;
      }
      }
    }
  }
}