Example #1
0
void ModuleFile::getImportDecls(SmallVectorImpl<Decl *> &Results) {
  if (!Bits.ComputedImportDecls) {
    ASTContext &Ctx = getContext();
    for (auto &Dep : Dependencies) {
      // FIXME: We need a better way to show headers, since they usually /are/
      // re-exported. This isn't likely to come up much, though.
      if (Dep.isHeader())
        continue;

      StringRef ModulePathStr = Dep.RawPath;
      StringRef ScopePath;
      if (Dep.isScoped())
        std::tie(ModulePathStr, ScopePath) = ModulePathStr.rsplit('\0');

      SmallVector<std::pair<swift::Identifier, swift::SourceLoc>, 1> AccessPath;
      while (!ModulePathStr.empty()) {
        StringRef NextComponent;
        std::tie(NextComponent, ModulePathStr) = ModulePathStr.split('\0');
        AccessPath.push_back({Ctx.getIdentifier(NextComponent), SourceLoc()});
      }

      if (AccessPath.size() == 1 && AccessPath[0].first == Ctx.StdlibModuleName)
        continue;

      Module *M = Ctx.getModule(AccessPath);

      auto Kind = ImportKind::Module;
      if (!ScopePath.empty()) {
        auto ScopeID = Ctx.getIdentifier(ScopePath);
        assert(!ScopeID.empty() &&
               "invalid decl name (non-top-level decls not supported)");

        if (!M) {
          // The dependency module could not be loaded.  Just make a guess
          // about the import kind, we cannot do better.
          Kind = ImportKind::Func;
        } else {
          // Lookup the decl in the top-level module.
          Module *TopLevelModule = M;
          if (AccessPath.size() > 1)
            TopLevelModule = Ctx.getLoadedModule(AccessPath.front().first);

          SmallVector<ValueDecl *, 8> Decls;
          TopLevelModule->lookupQualified(
              ModuleType::get(TopLevelModule), ScopeID,
              NL_QualifiedDefault | NL_KnownNoDependency, nullptr, Decls);
          Optional<ImportKind> FoundKind = ImportDecl::findBestImportKind(Decls);
          assert(FoundKind.hasValue() &&
                 "deserialized imports should not be ambiguous");
          Kind = *FoundKind;
        }

        AccessPath.push_back({ ScopeID, SourceLoc() });
      }

      auto *ID = ImportDecl::create(Ctx, FileContext, SourceLoc(), Kind,
                                    SourceLoc(), AccessPath);
      ID->setModule(M);
      if (Dep.isExported())
        ID->getAttrs().add(
            new (Ctx) ExportedAttr(/*IsImplicit=*/false));
      ImportDecls.push_back(ID);
    }
    Bits.ComputedImportDecls = true;
  }
  Results.append(ImportDecls.begin(), ImportDecls.end());
}
Example #2
0
/// InsertUnwindResumeCalls - Convert the ResumeInsts that are still present
/// into calls to the appropriate _Unwind_Resume function.
bool DwarfEHPrepare::InsertUnwindResumeCalls(Function &Fn) {
  SmallVector<ResumeInst*, 16> Resumes;
  for (Function::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) {
    TerminatorInst *TI = I->getTerminator();
    if (ResumeInst *RI = dyn_cast<ResumeInst>(TI))
      Resumes.push_back(RI);
  }

  if (Resumes.empty())
    return false;

  // Find the rewind function if we didn't already.
  const TargetLowering *TLI = TM->getTargetLowering();
  if (!RewindFunction) {
    LLVMContext &Ctx = Resumes[0]->getContext();
    FunctionType *FTy = FunctionType::get(Type::getVoidTy(Ctx),
                                          Type::getInt8PtrTy(Ctx), false);
    const char *RewindName = TLI->getLibcallName(RTLIB::UNWIND_RESUME);
    RewindFunction = Fn.getParent()->getOrInsertFunction(RewindName, FTy);
  }

  // Create the basic block where the _Unwind_Resume call will live.
  LLVMContext &Ctx = Fn.getContext();
  unsigned ResumesSize = Resumes.size();

  if (ResumesSize == 1) {
    // Instead of creating a new BB and PHI node, just append the call to
    // _Unwind_Resume to the end of the single resume block.
    ResumeInst *RI = Resumes.front();
    BasicBlock *UnwindBB = RI->getParent();
    Value *ExnObj = GetExceptionObject(RI);

    // Call the _Unwind_Resume function.
    CallInst *CI = CallInst::Create(RewindFunction, ExnObj, "", UnwindBB);
    CI->setCallingConv(TLI->getLibcallCallingConv(RTLIB::UNWIND_RESUME));

    // We never expect _Unwind_Resume to return.
    new UnreachableInst(Ctx, UnwindBB);
    return true;
  }

  BasicBlock *UnwindBB = BasicBlock::Create(Ctx, "unwind_resume", &Fn);
  PHINode *PN = PHINode::Create(Type::getInt8PtrTy(Ctx), ResumesSize,
                                "exn.obj", UnwindBB);

  // Extract the exception object from the ResumeInst and add it to the PHI node
  // that feeds the _Unwind_Resume call.
  for (SmallVectorImpl<ResumeInst*>::iterator
         I = Resumes.begin(), E = Resumes.end(); I != E; ++I) {
    ResumeInst *RI = *I;
    BasicBlock *Parent = RI->getParent();
    BranchInst::Create(UnwindBB, Parent);

    Value *ExnObj = GetExceptionObject(RI);
    PN->addIncoming(ExnObj, Parent);

    ++NumResumesLowered;
  }

  // Call the function.
  CallInst *CI = CallInst::Create(RewindFunction, PN, "", UnwindBB);
  CI->setCallingConv(TLI->getLibcallCallingConv(RTLIB::UNWIND_RESUME));

  // We never expect _Unwind_Resume to return.
  new UnreachableInst(Ctx, UnwindBB);
  return true;
}
Example #3
0
Status ModuleFile::associateWithFileContext(FileUnit *file,
                                            SourceLoc diagLoc) {
  PrettyModuleFileDeserialization stackEntry(*this);

  assert(getStatus() == Status::Valid && "invalid module file");
  assert(!FileContext && "already associated with an AST module");
  FileContext = file;

  if (file->getParentModule()->getName().str() != Name)
    return error(Status::NameMismatch);

  ASTContext &ctx = getContext();

  llvm::Triple moduleTarget(llvm::Triple::normalize(TargetTriple));
  if (!areCompatibleArchitectures(moduleTarget, ctx.LangOpts.Target) ||
      !areCompatibleOSs(moduleTarget, ctx.LangOpts.Target)) {
    return error(Status::TargetIncompatible);
  }
  if (ctx.LangOpts.EnableTargetOSChecking &&
      isTargetTooNew(moduleTarget, ctx.LangOpts.Target)) {
    return error(Status::TargetTooNew);
  }

  for (const auto &searchPathPair : SearchPaths)
    ctx.addSearchPath(searchPathPair.first, searchPathPair.second);

  auto clangImporter = static_cast<ClangImporter *>(ctx.getClangModuleLoader());

  bool missingDependency = false;
  for (auto &dependency : Dependencies) {
    assert(!dependency.isLoaded() && "already loaded?");

    if (dependency.isHeader()) {
      // The path may be empty if the file being loaded is a partial AST,
      // and the current compiler invocation is a merge-modules step.
      if (!dependency.RawPath.empty()) {
        bool hadError =
            clangImporter->importHeader(dependency.RawPath,
                                        file->getParentModule(),
                                        importedHeaderInfo.fileSize,
                                        importedHeaderInfo.fileModTime,
                                        importedHeaderInfo.contents,
                                        diagLoc);
        if (hadError)
          return error(Status::FailedToLoadBridgingHeader);
      }
      Module *importedHeaderModule = clangImporter->getImportedHeaderModule();
      dependency.Import = { {}, importedHeaderModule };
      continue;
    }

    StringRef modulePathStr = dependency.RawPath;
    StringRef scopePath;
    if (dependency.isScoped()) {
      auto splitPoint = modulePathStr.find_last_of('\0');
      assert(splitPoint != StringRef::npos);
      scopePath = modulePathStr.substr(splitPoint+1);
      modulePathStr = modulePathStr.slice(0, splitPoint);
    }

    SmallVector<Identifier, 4> modulePath;
    while (!modulePathStr.empty()) {
      StringRef nextComponent;
      std::tie(nextComponent, modulePathStr) = modulePathStr.split('\0');
      modulePath.push_back(ctx.getIdentifier(nextComponent));
      assert(!modulePath.back().empty() &&
             "invalid module name (submodules not yet supported)");
    }
    auto module = getModule(modulePath);
    if (!module) {
      // If we're missing the module we're shadowing, treat that specially.
      if (modulePath.size() == 1 &&
          modulePath.front() == file->getParentModule()->getName()) {
        return error(Status::MissingShadowedModule);
      }

      // Otherwise, continue trying to load dependencies, so that we can list
      // everything that's missing.
      missingDependency = true;
      continue;
    }

    // This is for backwards-compatibility with modules that still rely on the
    // "HasUnderlyingModule" flag.
    if (Bits.HasUnderlyingModule && module == ShadowedModule)
      dependency.forceExported();

    if (scopePath.empty()) {
      dependency.Import = { {}, module };
    } else {
      auto scopeID = ctx.getIdentifier(scopePath);
      assert(!scopeID.empty() &&
             "invalid decl name (non-top-level decls not supported)");
      auto path = Module::AccessPathTy({scopeID, SourceLoc()});
      dependency.Import = { ctx.AllocateCopy(path), module };
    }
  }

  if (missingDependency) {
    return error(Status::MissingDependency);
  }

  if (Bits.HasEntryPoint) {
    FileContext->getParentModule()->registerEntryPointFile(FileContext,
                                                           SourceLoc(),
                                                           None);
  }

  return getStatus();
}
Example #4
0
void NameBinder::addImport(
    SmallVectorImpl<std::pair<ImportedModule, ImportOptions>> &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;
    }

    Module *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);

    Module *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);
        assert(topLevelModule && "top-level module missing");
    }

    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();
    }

    ImportOptions options;
    if (ID->isExported())
        options |= SourceFile::ImportFlags::Exported;
    if (testableAttr)
        options |= SourceFile::ImportFlags::Testable;
    imports.push_back({ { ID->getDeclPath(), M }, options });

    if (topLevelModule != M)
        imports.push_back({ { ID->getDeclPath(), topLevelModule }, options });

    if (ID->getImportKind() != ImportKind::Module) {
        // If we're importing a specific decl, validate the import kind.
        using namespace namelookup;
        auto declPath = ID->getDeclPath();

        // FIXME: Doesn't handle scoped testable imports correctly.
        assert(declPath.size() == 1 && "can't handle sub-decl imports");
        SmallVector<ValueDecl *, 8> decls;
        lookupInModule(topLevelModule, declPath, declPath.front().first, decls,
                       NLKind::QualifiedLookup, ResolutionKind::Overloadable,
                       /*resolver*/nullptr, &SF);

        if (decls.empty()) {
            diagnose(ID, diag::no_decl_in_module)
            .highlight(SourceRange(declPath.front().second,
                                   declPath.back().second));
            return;
        }

        ID->setDecls(Context.AllocateCopy(decls));

        Optional<ImportKind> actualKind = ImportDecl::findBestImportKind(decls);
        if (!actualKind.hasValue()) {
            // FIXME: print entire module name?
            diagnose(ID, diag::ambiguous_decl_in_module,
                     declPath.front().first, M->getName());
            for (auto next : decls)
                diagnose(next, diag::found_candidate);

        } else if (!isCompatibleImportKind(ID->getImportKind(), *actualKind)) {
            diagnose(ID, diag::imported_decl_is_wrong_kind,
                     declPath.front().first,
                     getImportKindString(ID->getImportKind()),
                     static_cast<unsigned>(*actualKind))
            .fixItReplace(SourceRange(ID->getKindLoc()),
                          getImportKindString(*actualKind));

            if (decls.size() == 1)
                diagnose(decls.front(), diag::decl_declared_here,
                         decls.front()->getName());
        }
    }
}
Example #5
0
void SILGenFunction::emitArtificialTopLevel(ClassDecl *mainClass) {
  // Load argc and argv from the entry point arguments.
  SILValue argc = F.begin()->getBBArg(0);
  SILValue argv = F.begin()->getBBArg(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();
    Module *UIKit = ctx.getLoadedModule(ctx.getIdentifier("UIKit"));
    SmallVector<ValueDecl *, 1> results;
    UIKit->lookupQualified(UIKit->getDeclaredType(),
                           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();

    // Get the class name as a string using NSStringFromClass.
    CanType mainClassTy = mainClass->getDeclaredTypeInContext()->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
      ->getDeclaredTypeInContext()
      ->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, IsNotFragile);
    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 = fnTy->getSILArgumentType(3);
    assert(nameArgTy == fnTy->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) {
        return input;
      });
    }

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

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

    auto managedArgv = ManagedValue::forUnmanaged(argv);

    if (unwrappedTy != argv->getType()) {
      auto converted =
          emitPointerToPointer(mainClass, managedArgv,
                               argv->getType().getSwiftRValueType(),
                               unwrappedTy.getSwiftRValueType());
      managedArgv = std::move(converted).getAsSingleValue(*this, mainClass);
    }

    if (unwrappedTy != argvTy) {
      managedArgv = getOptionalSomeValue(mainClass, managedArgv,
                                         getTypeLowering(argvTy));
    }

    auto UIApplicationMain = B.createFunctionRef(mainClass, UIApplicationMainFn);

    SILValue args[] = {argc, managedArgv.getValue(), nilValue,
                       managedName.getValue()};

    B.createApply(mainClass, UIApplicationMain,
                  UIApplicationMain->getType(),
                  argc->getType(), {}, args);
    SILValue r = B.createIntegerLiteral(mainClass,
                        SILType::getBuiltinIntegerType(32, ctx), 0);
    auto rType = F.getLoweredFunctionType()->getSingleResult().getSILType();
    if (r->getType() != rType)
      r = B.createStruct(mainClass, rType, r);

    Cleanups.emitCleanupsForReturn(mainClass);
    B.createReturn(mainClass, r);
    return;
  }

  case ArtificialMainKind::NSApplicationMain: {
    // Emit an AppKit main.
    // return NSApplicationMain(C_ARGC, C_ARGV);

    SILParameterInfo argTypes[] = {
      SILParameterInfo(argc->getType().getSwiftRValueType(),
                       ParameterConvention::Direct_Unowned),
      SILParameterInfo(argv->getType().getSwiftRValueType(),
                       ParameterConvention::Direct_Unowned),
    };
    auto NSApplicationMainType = SILFunctionType::get(nullptr,
                  SILFunctionType::ExtInfo()
                    // Should be C calling convention, but NSApplicationMain
                    // has an overlay to fix the type of argv.
                    .withRepresentation(SILFunctionType::Representation::Thin),
                  ParameterConvention::Direct_Unowned,
                  argTypes,
                  SILResultInfo(argc->getType().getSwiftRValueType(),
                                ResultConvention::Unowned),
                  /*error result*/ None,
                  getASTContext());

    auto NSApplicationMainFn
      = SGM.M.getOrCreateFunction(mainClass, "NSApplicationMain",
                                  SILLinkage::PublicExternal,
                                  NSApplicationMainType,
                                  IsBare, IsTransparent, IsNotFragile);

    auto NSApplicationMain = B.createFunctionRef(mainClass, NSApplicationMainFn);
    SILValue args[] = { argc, argv };

    B.createApply(mainClass, NSApplicationMain,
                  NSApplicationMain->getType(),
                  argc->getType(), {}, args);
    SILValue r = B.createIntegerLiteral(mainClass,
                        SILType::getBuiltinIntegerType(32, getASTContext()), 0);
    auto rType = F.getLoweredFunctionType()->getSingleResult().getSILType();
    if (r->getType() != rType)
      r = B.createStruct(mainClass, rType, r);
    B.createReturn(mainClass, r);
    return;
  }
  }
}
void swift::ide::printSubmoduleInterface(
       Module *M,
       ArrayRef<StringRef> FullModuleName,
       ArrayRef<StringRef> GroupNames,
       ModuleTraversalOptions TraversalOptions,
       ASTPrinter &Printer,
       const PrintOptions &Options,
       const bool PrintSynthesizedExtensions) {
  auto AdjustedOptions = Options;
  adjustPrintOptions(AdjustedOptions);

  SmallVector<Decl *, 1> Decls;
  M->getDisplayDecls(Decls);

  auto &SwiftContext = M->getASTContext();
  auto &Importer =
      static_cast<ClangImporter &>(*SwiftContext.getClangModuleLoader());

  const clang::Module *InterestingClangModule = nullptr;

  SmallVector<ImportDecl *, 1> ImportDecls;
  llvm::DenseSet<const clang::Module *> ClangModulesForImports;
  SmallVector<Decl *, 1> SwiftDecls;
  llvm::DenseMap<const clang::Module *,
                 SmallVector<std::pair<Decl *, clang::SourceLocation>, 1>>
    ClangDecls;

  // Drop top-level module name.
  FullModuleName = FullModuleName.slice(1);

  InterestingClangModule = M->findUnderlyingClangModule();
  if (InterestingClangModule) {
    for (StringRef Name : FullModuleName) {
      InterestingClangModule = InterestingClangModule->findSubmodule(Name);
      if (!InterestingClangModule)
        return;
    }
  } else {
    assert(FullModuleName.empty());
  }

  // If we're printing recursively, find all of the submodules to print.
  if (InterestingClangModule) {
    if (TraversalOptions) {
      SmallVector<const clang::Module *, 8> Worklist;
      SmallPtrSet<const clang::Module *, 8> Visited;
      Worklist.push_back(InterestingClangModule);
      Visited.insert(InterestingClangModule);
      while (!Worklist.empty()) {
        const clang::Module *CM = Worklist.pop_back_val();
        if (!(TraversalOptions & ModuleTraversal::VisitHidden) &&
            CM->IsExplicit)
          continue;

        ClangDecls.insert({ CM, {} });

        // If we're supposed to visit submodules, add them now.
        if (TraversalOptions & ModuleTraversal::VisitSubmodules) {
          for (auto Sub = CM->submodule_begin(), SubEnd = CM->submodule_end();
               Sub != SubEnd; ++Sub) {
            if (Visited.insert(*Sub).second)
              Worklist.push_back(*Sub);
          }
        }
      }
    } else {
      ClangDecls.insert({ InterestingClangModule, {} });
    }
  }

  // Collect those submodules that are actually imported but have no import decls
  // in the module.
  llvm::SmallPtrSet<const clang::Module *, 16> NoImportSubModules;
  if (InterestingClangModule) {
    // Assume all submodules are missing.
    for (auto It =InterestingClangModule->submodule_begin();
         It != InterestingClangModule->submodule_end(); It ++) {
      NoImportSubModules.insert(*It);
    }
  }
  llvm::StringMap<std::vector<Decl*>> FileRangedDecls;
  // Separate the declarations that we are going to print into different
  // buckets.
  for (Decl *D : Decls) {

    // Skip declarations that are not accessible.
    if (auto *VD = dyn_cast<ValueDecl>(D)) {
      if (Options.AccessibilityFilter > Accessibility::Private &&
          VD->hasAccessibility() &&
          VD->getFormalAccess() < Options.AccessibilityFilter)
        continue;
    }

    auto ShouldPrintImport = [&](ImportDecl *ImportD) -> bool {
      if (!InterestingClangModule)
        return true;
      auto ClangMod = ImportD->getClangModule();
      if (!ClangMod)
        return true;
      if (!ClangMod->isSubModule())
        return true;
      if (ClangMod == InterestingClangModule)
        return false;
      // FIXME: const-ness on the clang API.
      return ClangMod->isSubModuleOf(
                          const_cast<clang::Module*>(InterestingClangModule));
    };

    if (auto ID = dyn_cast<ImportDecl>(D)) {
      if (ShouldPrintImport(ID)) {
        if (ID->getClangModule())
          // Erase those submodules that are not missing.
          NoImportSubModules.erase(ID->getClangModule());
        if (ID->getImportKind() == ImportKind::Module) {
          // Make sure we don't print duplicate imports, due to getting imports
          // for both a clang module and its overlay.
          if (auto *ClangMod = getUnderlyingClangModuleForImport(ID)) {
            auto P = ClangModulesForImports.insert(ClangMod);
            bool IsNew = P.second;
            if (!IsNew)
              continue;
          }
        }
        ImportDecls.push_back(ID);
      }
      continue;
    }

    auto addToClangDecls = [&](Decl *D) {
      assert(D->hasClangNode());
      auto CN = D->getClangNode();
      clang::SourceLocation Loc = CN.getLocation();

      auto *OwningModule = Importer.getClangOwningModule(CN);
      auto I = ClangDecls.find(OwningModule);
      if (I != ClangDecls.end()) {
        I->second.push_back({ D, Loc });
      }
    };

    if (D->hasClangNode()) {
      addToClangDecls(D);
      continue;
    }
    if (FullModuleName.empty()) {
      // If group name is given and the decl does not belong to the group, skip it.
      if (!GroupNames.empty()){
        if (auto Target = D->getGroupName()) {
          if (std::find(GroupNames.begin(), GroupNames.end(),
                        Target.getValue()) != GroupNames.end()) {
            FileRangedDecls.insert(std::make_pair(D->getSourceFileName().getValue(),
              std::vector<Decl*>())).first->getValue().push_back(D);
          }
        }
        continue;
      }
      // Add Swift decls if we are printing the top-level module.
      SwiftDecls.push_back(D);
    }
  }
  if (!GroupNames.empty()) {
    assert(SwiftDecls.empty());
    for (auto &Entry : FileRangedDecls) {
      auto &DeclsInFile = Entry.getValue();
      std::sort(DeclsInFile.begin(), DeclsInFile.end(),
                [](Decl* LHS, Decl *RHS) {
                  assert(LHS->getSourceOrder().hasValue());
                  assert(RHS->getSourceOrder().hasValue());
                  return LHS->getSourceOrder().getValue() <
                         RHS->getSourceOrder().getValue();
                });

      for (auto D : DeclsInFile) {
        SwiftDecls.push_back(D);
      }
    }
  }

  // Create the missing import decls and add to the collector.
  for (auto *SM : NoImportSubModules) {
    ImportDecls.push_back(createImportDecl(M->getASTContext(), M, SM, {}));
  }

  auto &ClangSourceManager = Importer.getClangASTContext().getSourceManager();

  // Sort imported declarations in source order *within a submodule*.
  for (auto &P : ClangDecls) {
    std::sort(P.second.begin(), P.second.end(),
              [&](std::pair<Decl *, clang::SourceLocation> LHS,
                  std::pair<Decl *, clang::SourceLocation> RHS) -> bool {
                return ClangSourceManager.isBeforeInTranslationUnit(LHS.second,
                                                                    RHS.second);
              });
  }

  // Sort Swift declarations so that we print them in a consistent order.
  std::sort(ImportDecls.begin(), ImportDecls.end(),
            [](ImportDecl *LHS, ImportDecl *RHS) -> bool {
    auto LHSPath = LHS->getFullAccessPath();
    auto RHSPath = RHS->getFullAccessPath();
    for (unsigned i = 0, e = std::min(LHSPath.size(), RHSPath.size()); i != e;
         i++) {
      if (int Ret = LHSPath[i].first.str().compare(RHSPath[i].first.str()))
        return Ret < 0;
    }
    return false;
  });

  // If the group name is specified, we sort them according to their source order,
  // which is the order preserved by getTopLeveDecls.
  if (GroupNames.empty()) {
    std::sort(SwiftDecls.begin(), SwiftDecls.end(),
      [&](Decl *LHS, Decl *RHS) -> bool {
        auto *LHSValue = dyn_cast<ValueDecl>(LHS);
        auto *RHSValue = dyn_cast<ValueDecl>(RHS);

        if (LHSValue && RHSValue) {
          StringRef LHSName = LHSValue->getName().str();
          StringRef RHSName = RHSValue->getName().str();
          if (int Ret = LHSName.compare(RHSName))
            return Ret < 0;
          // FIXME: this is not sufficient to establish a total order for overloaded
          // decls.
          return LHS->getKind() < RHS->getKind();
        }

        return LHS->getKind() < RHS->getKind();
      });
  }

  ASTPrinter *PrinterToUse = &Printer;

  ClangCommentPrinter RegularCommentPrinter(Printer, Importer);
  if (Options.PrintRegularClangComments)
    PrinterToUse = &RegularCommentPrinter;

  auto PrintDecl = [&](Decl *D) -> bool {
    ASTPrinter &Printer = *PrinterToUse;
    if (!shouldPrint(D, AdjustedOptions)) {
      Printer.callAvoidPrintDeclPost(D);
      return false;
    }
    if (auto Ext = dyn_cast<ExtensionDecl>(D)) {
      // Clang extensions (categories) are always printed in source order.
      // Swift extensions are printed with their associated type unless it's
      // a cross-module extension.
      if (!Ext->hasClangNode()) {
        auto ExtendedNominal = Ext->getExtendedType()->getAnyNominal();
        if (Ext->getModuleContext() == ExtendedNominal->getModuleContext())
          return false;
      }
    }
    std::unique_ptr<SynthesizedExtensionAnalyzer> pAnalyzer;
    if (auto NTD = dyn_cast<NominalTypeDecl>(D)) {
      if (PrintSynthesizedExtensions) {
        pAnalyzer.reset(new SynthesizedExtensionAnalyzer(NTD, AdjustedOptions));
        AdjustedOptions.shouldCloseNominal = !pAnalyzer->hasMergeGroup(
          SynthesizedExtensionAnalyzer::MergeGroupKind::MergableWithTypeDef);
      }
    }
    if (D->print(Printer, AdjustedOptions)) {
      if (AdjustedOptions.shouldCloseNominal)
        Printer << "\n";
      AdjustedOptions.shouldCloseNominal = true;
      if (auto NTD = dyn_cast<NominalTypeDecl>(D)) {
        std::queue<NominalTypeDecl *> SubDecls{{NTD}};

        while (!SubDecls.empty()) {
          auto NTD = SubDecls.front();
          SubDecls.pop();

          // Add sub-types of NTD.
          for (auto Sub : NTD->getMembers())
            if (auto N = dyn_cast<NominalTypeDecl>(Sub))
              SubDecls.push(N);

          if (!PrintSynthesizedExtensions) {
            // Print Ext and add sub-types of Ext.
            for (auto Ext : NTD->getExtensions()) {
              if (!shouldPrint(Ext, AdjustedOptions)) {
                Printer.callAvoidPrintDeclPost(Ext);
                continue;
              }
              if (Ext->hasClangNode())
                continue; // will be printed in its source location, see above.
              Printer << "\n";
              Ext->print(Printer, AdjustedOptions);
              Printer << "\n";
              for (auto Sub : Ext->getMembers())
                if (auto N = dyn_cast<NominalTypeDecl>(Sub))
                  SubDecls.push(N);
            }
            continue;
          }

          bool IsTopLevelDecl = D == NTD;

          // If printed Decl is the top-level, merge the constraint-free extensions
          // into the main body.
          if (IsTopLevelDecl) {
          // Print the part that should be merged with the type decl.
          pAnalyzer->forEachExtensionMergeGroup(
            SynthesizedExtensionAnalyzer::MergeGroupKind::MergableWithTypeDef,
            [&](ArrayRef<ExtensionAndIsSynthesized> Decls){
              for (auto ET : Decls) {
                AdjustedOptions.shouldOpenExtension = false;
                AdjustedOptions.shouldCloseExtension =
                  Decls.back().first == ET.first;
                if (ET.second)
                  AdjustedOptions.
                    initArchetypeTransformerForSynthesizedExtensions(NTD,
                                                               pAnalyzer.get());
                ET.first->print(Printer, AdjustedOptions);
                if (ET.second)
                  AdjustedOptions.
                    clearArchetypeTransformerForSynthesizedExtensions();
                if (AdjustedOptions.shouldCloseExtension)
                  Printer << "\n";
              }
          });
          }

          // If the printed Decl is not the top-level one, reset analyzer.
          if (!IsTopLevelDecl)
            pAnalyzer.reset(new SynthesizedExtensionAnalyzer(NTD, AdjustedOptions));

          // Print the rest as synthesized extensions.
          pAnalyzer->forEachExtensionMergeGroup(
            // For top-level decls, only contraint extensions are to print;
            // Since the rest are merged into the main body.
            IsTopLevelDecl ?
              SynthesizedExtensionAnalyzer::MergeGroupKind::UnmergableWithTypeDef :
            // For sub-decls, all extensions should be printed.
              SynthesizedExtensionAnalyzer::MergeGroupKind::All,
            [&](ArrayRef<ExtensionAndIsSynthesized> Decls){
              for (auto ET : Decls) {
                AdjustedOptions.shouldOpenExtension =
                  Decls.front().first == ET.first;
                AdjustedOptions.shouldCloseExtension =
                  Decls.back().first == ET.first;
                if (AdjustedOptions.shouldOpenExtension)
                  Printer << "\n";
                if (ET.second)
                  AdjustedOptions.
                    initArchetypeTransformerForSynthesizedExtensions(NTD,
                                                               pAnalyzer.get());
                ET.first->print(Printer, AdjustedOptions);
                if (ET.second)
                  AdjustedOptions.
                    clearArchetypeTransformerForSynthesizedExtensions();
                if (AdjustedOptions.shouldCloseExtension)
                  Printer << "\n";
            }
          });
        }
      }
      return true;
    }
    return false;
  };

  // Imports from the stdlib are internal details that don't need to be exposed.
  if (!M->isStdlibModule()) {
    for (auto *D : ImportDecls)
      PrintDecl(D);
    Printer << "\n";
  }

  {
    using ModuleAndName = std::pair<const clang::Module *, std::string>;
    SmallVector<ModuleAndName, 8> ClangModules;
    for (auto P : ClangDecls) {
      ClangModules.push_back({ P.first, P.first->getFullModuleName() });
    }
    // Sort modules by name.
    std::sort(ClangModules.begin(), ClangModules.end(),
              [](const ModuleAndName &LHS, const ModuleAndName &RHS)
                -> bool {
                  return LHS.second < RHS.second;
              });

    for (auto CM : ClangModules) {
      for (auto DeclAndLoc : ClangDecls[CM.first])
        PrintDecl(DeclAndLoc.first);
    }
  }

  if (!(TraversalOptions & ModuleTraversal::SkipOverlay) ||
      !InterestingClangModule) {
    for (auto *D : SwiftDecls) {
      if (PrintDecl(D))
        Printer << "\n";
    }
  }
}
Example #7
0
Substitution Substitution::subst(Module *module,
                                 ArrayRef<Substitution> subs,
                                 TypeSubstitutionMap &subMap,
                                 ArchetypeConformanceMap &conformanceMap) const {
  // Substitute the replacement.
  Type substReplacement = Replacement.subst(module, subMap, None);
  assert(substReplacement && "substitution replacement failed");

  if (substReplacement->isEqual(Replacement))
    return *this;

  if (Conformance.empty()) {
    return {substReplacement, Conformance};
  }

  bool conformancesChanged = false;
  SmallVector<ProtocolConformanceRef, 4> substConformances;
  substConformances.reserve(Conformance.size());

  for (auto c : Conformance) {
    // If we have a concrete conformance, we need to substitute the
    // conformance to apply to the new type.
    if (c.isConcrete()) {
      auto substC = c.getConcrete()->subst(module, substReplacement, subs,
                                           subMap, conformanceMap);
      substConformances.push_back(ProtocolConformanceRef(substC));
      if (c != substConformances.back())
        conformancesChanged = true;
      continue;
    }

    // Otherwise, we may need to fill in the conformance.
    ProtocolDecl *proto = c.getAbstract();
    Optional<ProtocolConformanceRef> conformance;

    // If the original type was an archetype, check the conformance map.
    if (auto replacementArch = Replacement->getAs<ArchetypeType>()) {
      // Check for conformances for the type that apply to the original
      // substituted archetype.
      auto it = conformanceMap.find(replacementArch);
      assert(it != conformanceMap.end());
      for (ProtocolConformanceRef found : it->second) {
        auto foundProto = found.getRequirement();
        if (foundProto == proto) {
          conformance = found;
          break;
        } else if (foundProto->inheritsFrom(proto)) {
          if (found.isConcrete()) {
            conformance = ProtocolConformanceRef(
              found.getConcrete()->getInheritedConformance(proto));
          } else {
            conformance = found;
          }
          break;
        }
      }
    }

    // If that didn't find anything, we can still synthesize AnyObject
    // conformances from thin air.  FIXME: gross.
    if (!conformance &&
        proto->isSpecificProtocol(KnownProtocolKind::AnyObject)) {
      auto classDecl
        = substReplacement->getClassOrBoundGenericClass();
      SmallVector<ProtocolConformance *, 1> lookupResults;
      classDecl->lookupConformance(classDecl->getParentModule(),
                                   proto, lookupResults);
      conformance = ProtocolConformanceRef(lookupResults.front());
    }

    if (conformance) {
      if (conformance->isConcrete())
        conformancesChanged = true;
      substConformances.push_back(*conformance);
    } else {
      assert(substReplacement->hasDependentProtocolConformances() &&
             "couldn't find concrete conformance for concrete type?");
      substConformances.push_back(ProtocolConformanceRef(proto));
    }
  }
  assert(substConformances.size() == Conformance.size());

  ArrayRef<ProtocolConformanceRef> substConfs;
  if (conformancesChanged)
    substConfs = module->getASTContext().AllocateCopy(substConformances);
  else
    substConfs = Conformance;

  return Substitution{substReplacement, substConfs};
}
/// InsertUnwindResumeCalls - Convert the ResumeInsts that are still present
/// into calls to the appropriate _Unwind_Resume function.
bool DwarfEHPrepare::InsertUnwindResumeCalls(Function &Fn) {
  SmallVector<ResumeInst*, 16> Resumes;
  SmallVector<LandingPadInst*, 16> CleanupLPads;
  for (BasicBlock &BB : Fn) {
    if (auto *RI = dyn_cast<ResumeInst>(BB.getTerminator()))
      Resumes.push_back(RI);
    if (auto *LP = BB.getLandingPadInst())
      if (LP->isCleanup())
        CleanupLPads.push_back(LP);
  }

  if (Resumes.empty())
    return false;

  // Check the personality, don't do anything if it's funclet-based.
  EHPersonality Pers = classifyEHPersonality(Fn.getPersonalityFn());
  if (isFuncletEHPersonality(Pers))
    return false;

  LLVMContext &Ctx = Fn.getContext();

  size_t ResumesLeft = pruneUnreachableResumes(Fn, Resumes, CleanupLPads);
  if (ResumesLeft == 0)
    return true; // We pruned them all.

  // Find the rewind function if we didn't already.
  if (!RewindFunction) {
    FunctionType *FTy = FunctionType::get(Type::getVoidTy(Ctx),
                                          Type::getInt8PtrTy(Ctx), false);
    const char *RewindName = TLI->getLibcallName(RTLIB::UNWIND_RESUME);
    RewindFunction = Fn.getParent()->getOrInsertFunction(RewindName, FTy);
  }

  // Create the basic block where the _Unwind_Resume call will live.
  if (ResumesLeft == 1) {
    // Instead of creating a new BB and PHI node, just append the call to
    // _Unwind_Resume to the end of the single resume block.
    ResumeInst *RI = Resumes.front();
    BasicBlock *UnwindBB = RI->getParent();
    Value *ExnObj = GetExceptionObject(RI);

    // Call the _Unwind_Resume function.
    CallInst *CI = CallInst::Create(RewindFunction, ExnObj, "", UnwindBB);
    CI->setCallingConv(TLI->getLibcallCallingConv(RTLIB::UNWIND_RESUME));

    // We never expect _Unwind_Resume to return.
    new UnreachableInst(Ctx, UnwindBB);
    return true;
  }

  BasicBlock *UnwindBB = BasicBlock::Create(Ctx, "unwind_resume", &Fn);
  PHINode *PN = PHINode::Create(Type::getInt8PtrTy(Ctx), ResumesLeft,
                                "exn.obj", UnwindBB);

  // Extract the exception object from the ResumeInst and add it to the PHI node
  // that feeds the _Unwind_Resume call.
  for (ResumeInst *RI : Resumes) {
    BasicBlock *Parent = RI->getParent();
    BranchInst::Create(UnwindBB, Parent);

    Value *ExnObj = GetExceptionObject(RI);
    PN->addIncoming(ExnObj, Parent);

    ++NumResumesLowered;
  }

  // Call the function.
  CallInst *CI = CallInst::Create(RewindFunction, PN, "", UnwindBB);
  CI->setCallingConv(TLI->getLibcallCallingConv(RTLIB::UNWIND_RESUME));

  // We never expect _Unwind_Resume to return.
  new UnreachableInst(Ctx, UnwindBB);
  return true;
}
TypeIndex llvm::codeview::getModifiedType(const CVType &CVT) {
  assert(CVT.kind() == LF_MODIFIER);
  SmallVector<TypeIndex, 1> Refs;
  discoverTypeIndices(CVT, Refs);
  return Refs.front();
}
Example #10
0
void NamedParameterCheck::check(const MatchFinder::MatchResult &Result) {
  const SourceManager &SM = *Result.SourceManager;
  const auto *Function = Result.Nodes.getNodeAs<FunctionDecl>("decl");
  SmallVector<std::pair<const FunctionDecl *, unsigned>, 4> UnnamedParams;

  // Ignore implicitly generated members.
  if (Function->isImplicit())
    return;

  // Ignore declarations without a definition if we're not dealing with an
  // overriden method.
  const FunctionDecl *Definition = nullptr;
  if ((!Function->isDefined(Definition) || Function->isDefaulted() ||
       Function->isDeleted()) &&
      (!isa<CXXMethodDecl>(Function) ||
       cast<CXXMethodDecl>(Function)->size_overridden_methods() == 0))
    return;

  // TODO: Handle overloads.
  // TODO: We could check that all redeclarations use the same name for
  //       arguments in the same position.
  for (unsigned I = 0, E = Function->getNumParams(); I != E; ++I) {
    const ParmVarDecl *Parm = Function->getParamDecl(I);
    // Look for unnamed parameters.
    if (!Parm->getName().empty())
      continue;

    // Don't warn on the dummy argument on post-inc and post-dec operators.
    if ((Function->getOverloadedOperator() == OO_PlusPlus ||
         Function->getOverloadedOperator() == OO_MinusMinus) &&
        Parm->getType()->isSpecificBuiltinType(BuiltinType::Int))
      continue;

    // Sanity check the source locations.
    if (!Parm->getLocation().isValid() || Parm->getLocation().isMacroID() ||
        !SM.isWrittenInSameFile(Parm->getLocStart(), Parm->getLocation()))
      continue;

    // Skip gmock testing::Unused parameters.
    if (auto Typedef = Parm->getType()->getAs<clang::TypedefType>())
      if (Typedef->getDecl()->getQualifiedNameAsString() == "testing::Unused")
        continue;

    // Skip std::nullptr_t.
    if (Parm->getType().getCanonicalType()->isNullPtrType())
      continue;

    // Look for comments. We explicitly want to allow idioms like
    // void foo(int /*unused*/)
    const char *Begin = SM.getCharacterData(Parm->getLocStart());
    const char *End = SM.getCharacterData(Parm->getLocation());
    StringRef Data(Begin, End - Begin);
    if (Data.find("/*") != StringRef::npos)
      continue;

    UnnamedParams.push_back(std::make_pair(Function, I));
  }

  // Emit only one warning per function but fixits for all unnamed parameters.
  if (!UnnamedParams.empty()) {
    const ParmVarDecl *FirstParm =
        UnnamedParams.front().first->getParamDecl(UnnamedParams.front().second);
    auto D = diag(FirstParm->getLocation(),
                  "all parameters should be named in a function");

    for (auto P : UnnamedParams) {
      // Fallback to an unused marker.
      StringRef NewName = "unused";

      // If the method is overridden, try to copy the name from the base method
      // into the overrider.
      const auto *M = dyn_cast<CXXMethodDecl>(P.first);
      if (M && M->size_overridden_methods() > 0) {
        const ParmVarDecl *OtherParm =
            (*M->begin_overridden_methods())->getParamDecl(P.second);
        StringRef Name = OtherParm->getName();
        if (!Name.empty())
          NewName = Name;
      }

      // If the definition has a named parameter use that name.
      if (Definition) {
        const ParmVarDecl *DefParm = Definition->getParamDecl(P.second);
        StringRef Name = DefParm->getName();
        if (!Name.empty())
          NewName = Name;
      }

      // Now insert the comment. Note that getLocation() points to the place
      // where the name would be, this allows us to also get complex cases like
      // function pointers right.
      const ParmVarDecl *Parm = P.first->getParamDecl(P.second);
      D << FixItHint::CreateInsertion(Parm->getLocation(),
                                      " /*" + NewName.str() + "*/");
    }
  }
}
Example #11
0
Substitution Substitution::subst(Module *module,
                                 ArrayRef<Substitution> subs,
                                 TypeSubstitutionMap &subMap,
                                 ArchetypeConformanceMap &conformanceMap) const {
  // Substitute the replacement.
  Type substReplacement = Replacement.subst(module, subMap, None);
  assert(substReplacement && "substitution replacement failed");

  if (substReplacement->isEqual(Replacement))
    return *this;

  bool conformancesChanged = false;
  SmallVector<ProtocolConformance *, 4> substConformance;
  substConformance.reserve(Conformance.size());

  // When substituting a concrete type for an archetype, we need to fill in the
  // conformances.
  if (auto replacementArch = Replacement->getAs<ArchetypeType>()) {
    if (!substReplacement->hasDependentProtocolConformances()) {
      // Find the conformances mapped to the archetype.
      auto found = conformanceMap.find(replacementArch);
      assert(found != conformanceMap.end()
             && "no conformances for replaced archetype?!");

      auto &foundConformances = found->second;

      // If the substituted replacement archetype has no conformances,
      // then there are no conformances to substitute.
      if (foundConformances.empty())
        return Substitution{Archetype, substReplacement, Conformance};

      conformancesChanged = true;

      // Get the conformances for the type that apply to the original
      // substituted archetype.
      for (auto proto : Archetype->getConformsTo()) {
        for (auto c : foundConformances) {
          if (c->getProtocol() == proto) {
            substConformance.push_back(c);
            goto found_conformance;
          }
          if (c->getProtocol()->inheritsFrom(proto)) {
            substConformance.push_back(c->getInheritedConformance(proto));
            goto found_conformance;
          }
        }

        // FIXME: AnyObject conformances can be synthesized from
        // thin air. Gross.
        if (proto->isSpecificProtocol(KnownProtocolKind::AnyObject)) {
          auto classDecl
            = substReplacement->getClassOrBoundGenericClass();
          SmallVector<ProtocolConformance *, 1> conformances;
          classDecl->lookupConformance(classDecl->getParentModule(),
                                       proto, conformances);
          substConformance.push_back(conformances.front());
          goto found_conformance;
        }

        assert(false && "did not find conformance for archetype requirement?!");
found_conformance:;
      }
    }
  } else {
    // If we substituted a concrete type for another, we need to substitute the
    // conformance to apply to the new type.
    for (auto c : Conformance) {
      auto substC = c->subst(module, substReplacement, subs,
                             subMap, conformanceMap);
      if (c != substC)
        conformancesChanged = true;
      substConformance.push_back(substC);
    }
  }

  ArrayRef<ProtocolConformance *> substConformanceRef;
  if (conformancesChanged)
    substConformanceRef = module->getASTContext().AllocateCopy(substConformance);
  else
    substConformanceRef = Conformance;

  assert(substReplacement->hasDependentProtocolConformances()
         || substConformanceRef.size() == Archetype->getConformsTo().size());

  return Substitution{Archetype, substReplacement, substConformanceRef};
}
static std::string fixupWithCase(StringRef Name,
                                 IdentifierNamingCheck::CaseType Case) {
  static llvm::Regex Splitter(
      "([a-z0-9A-Z]*)(_+)|([A-Z]?[a-z0-9]+)([A-Z]|$)|([A-Z]+)([A-Z]|$)");

  SmallVector<StringRef, 8> Substrs;
  Name.split(Substrs, "_", -1, false);

  SmallVector<StringRef, 8> Words;
  for (auto Substr : Substrs) {
    while (!Substr.empty()) {
      SmallVector<StringRef, 8> Groups;
      if (!Splitter.match(Substr, &Groups))
        break;

      if (Groups[2].size() > 0) {
        Words.push_back(Groups[1]);
        Substr = Substr.substr(Groups[0].size());
      } else if (Groups[3].size() > 0) {
        Words.push_back(Groups[3]);
        Substr = Substr.substr(Groups[0].size() - Groups[4].size());
      } else if (Groups[5].size() > 0) {
        Words.push_back(Groups[5]);
        Substr = Substr.substr(Groups[0].size() - Groups[6].size());
      }
    }
  }

  if (Words.empty())
    return Name;

  std::string Fixup;
  switch (Case) {
  case IdentifierNamingCheck::CT_AnyCase:
    Fixup += Name;
    break;

  case IdentifierNamingCheck::CT_LowerCase:
    for (auto const &Word : Words) {
      if (&Word != &Words.front())
        Fixup += "_";
      Fixup += Word.lower();
    }
    break;

  case IdentifierNamingCheck::CT_UpperCase:
    for (auto const &Word : Words) {
      if (&Word != &Words.front())
        Fixup += "_";
      Fixup += Word.upper();
    }
    break;

  case IdentifierNamingCheck::CT_CamelCase:
    for (auto const &Word : Words) {
      Fixup += Word.substr(0, 1).upper();
      Fixup += Word.substr(1).lower();
    }
    break;

  case IdentifierNamingCheck::CT_CamelBack:
    for (auto const &Word : Words) {
      if (&Word == &Words.front()) {
        Fixup += Word.lower();
      } else {
        Fixup += Word.substr(0, 1).upper();
        Fixup += Word.substr(1).lower();
      }
    }
    break;

  case IdentifierNamingCheck::CT_CamelSnakeCase:
    for (auto const &Word : Words) {
      if (&Word != &Words.front())
        Fixup += "_";
      Fixup += Word.substr(0, 1).upper();
      Fixup += Word.substr(1).lower();
    }
    break;

  case IdentifierNamingCheck::CT_CamelSnakeBack:
    for (auto const &Word : Words) {
      if (&Word != &Words.front()) {
        Fixup += "_";
        Fixup += Word.substr(0, 1).upper();
      } else {
        Fixup += Word.substr(0, 1).lower();
      }
      Fixup += Word.substr(1).lower();
    }
    break;
  }

  return Fixup;
}
Example #13
0
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);
    }

    auto managedArgv = ManagedValue::forUnmanaged(argv);

    if (unwrappedTy != argv->getType()) {
      auto converted =
          emitPointerToPointer(mainClass, managedArgv,
                               argv->getType().getASTType(),
                               unwrappedTy.getASTType());
      managedArgv = std::move(converted).getAsSingleValue(*this, mainClass);
    }

    if (unwrappedTy != argvTy) {
      managedArgv = getOptionalSomeValue(mainClass, managedArgv,
                                         getTypeLowering(argvTy));
    }

    auto UIApplicationMain = B.createFunctionRef(mainClass, UIApplicationMainFn);

    SILValue args[] = {argc, managedArgv.getValue(), nilValue,
                       managedName.getValue()};

    B.createApply(mainClass, UIApplicationMain,
                  UIApplicationMain->getType(),
                  argc->getType(), {}, args);
    SILValue r = B.createIntegerLiteral(mainClass,
                        SILType::getBuiltinIntegerType(32, ctx), 0);
    auto rType = F.getConventions().getSingleSILResultType();
    if (r->getType() != rType)
      r = B.createStruct(mainClass, rType, r);

    Cleanups.emitCleanupsForReturn(mainClass, NotForUnwind);
    B.createReturn(mainClass, r);
    return;
  }

  case ArtificialMainKind::NSApplicationMain: {
    // Emit an AppKit main.
    // return NSApplicationMain(C_ARGC, C_ARGV);

    SILParameterInfo argTypes[] = {
      SILParameterInfo(argc->getType().getASTType(),
                       ParameterConvention::Direct_Unowned),
      SILParameterInfo(argv->getType().getASTType(),
                       ParameterConvention::Direct_Unowned),
    };
    auto NSApplicationMainType = SILFunctionType::get(nullptr,
                  SILFunctionType::ExtInfo()
                    // Should be C calling convention, but NSApplicationMain
                    // has an overlay to fix the type of argv.
                    .withRepresentation(SILFunctionType::Representation::Thin),
                  SILCoroutineKind::None,
                  ParameterConvention::Direct_Unowned,
                  argTypes,
                  /*yields*/ {},
                  SILResultInfo(argc->getType().getASTType(),
                                ResultConvention::Unowned),
                  /*error result*/ None,
                  getASTContext());

    SILGenFunctionBuilder builder(SGM);
    auto NSApplicationMainFn = builder.getOrCreateFunction(
        mainClass, "NSApplicationMain", SILLinkage::PublicExternal,
        NSApplicationMainType, IsBare, IsTransparent, IsNotSerialized);

    auto NSApplicationMain = B.createFunctionRef(mainClass, NSApplicationMainFn);
    SILValue args[] = { argc, argv };

    B.createApply(mainClass, NSApplicationMain,
                  NSApplicationMain->getType(),
                  argc->getType(), {}, args);
    SILValue r = B.createIntegerLiteral(mainClass,
                        SILType::getBuiltinIntegerType(32, getASTContext()), 0);
    auto rType = F.getConventions().getSingleSILResultType();
    if (r->getType() != rType)
      r = B.createStruct(mainClass, rType, r);
    B.createReturn(mainClass, r);
    return;
  }
  }
}
Example #14
0
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));

  if (topLevelModule != M)
    imports.push_back(SourceFile::ImportedModuleDesc(
        {ID->getDeclPath(), topLevelModule}, options, privateImportFileName));

  if (ID->getImportKind() != ImportKind::Module) {
    // If we're importing a specific decl, validate the import kind.
    using namespace namelookup;
    auto declPath = ID->getDeclPath();

    // FIXME: Doesn't handle scoped testable imports correctly.
    assert(declPath.size() == 1 && "can't handle sub-decl imports");
    SmallVector<ValueDecl *, 8> decls;
    lookupInModule(topLevelModule, declPath, declPath.front().first, decls,
                   NLKind::QualifiedLookup, ResolutionKind::Overloadable,
                   /*resolver*/nullptr, &SF);

    if (decls.empty()) {
      diagnose(ID, diag::decl_does_not_exist_in_module,
               static_cast<unsigned>(ID->getImportKind()),
               declPath.front().first,
               ID->getModulePath().front().first)
        .highlight(SourceRange(declPath.front().second,
                               declPath.back().second));
      return;
    }

    ID->setDecls(Context.AllocateCopy(decls));

    Optional<ImportKind> actualKind = ImportDecl::findBestImportKind(decls);
    if (!actualKind.hasValue()) {
      // FIXME: print entire module name?
      diagnose(ID, diag::ambiguous_decl_in_module,
               declPath.front().first, M->getName());
      for (auto next : decls)
        diagnose(next, diag::found_candidate);

    } else if (!isCompatibleImportKind(ID->getImportKind(), *actualKind)) {
      Optional<InFlightDiagnostic> emittedDiag;
      if (*actualKind == ImportKind::Type &&
          isNominalImportKind(ID->getImportKind())) {
        assert(decls.size() == 1 &&
               "if we start suggesting ImportKind::Type for, e.g., a mix of "
               "structs and classes, we'll need a different message here");
        assert(isa<TypeAliasDecl>(decls.front()) &&
               "ImportKind::Type is only the best choice for a typealias");
        auto *typealias = cast<TypeAliasDecl>(decls.front());
        emittedDiag.emplace(diagnose(ID,
            diag::imported_decl_is_wrong_kind_typealias,
            typealias->getDescriptiveKind(),
            TypeAliasType::get(typealias, Type(), SubstitutionMap(),
                                typealias->getUnderlyingTypeLoc().getType()),
            getImportKindString(ID->getImportKind())));
      } else {
        emittedDiag.emplace(diagnose(ID, diag::imported_decl_is_wrong_kind,
            declPath.front().first,
            getImportKindString(ID->getImportKind()),
            static_cast<unsigned>(*actualKind)));
      }

      emittedDiag->fixItReplace(SourceRange(ID->getKindLoc()),
                                getImportKindString(*actualKind));
      emittedDiag->flush();

      if (decls.size() == 1)
        diagnose(decls.front(), diag::decl_declared_here,
                 decls.front()->getFullName());
    }
  }
}
Example #15
0
bool ModuleFile::readIndexBlock(llvm::BitstreamCursor &cursor) {
  cursor.EnterSubBlock(INDEX_BLOCK_ID);

  SmallVector<uint64_t, 4> scratch;
  StringRef blobData;

  while (true) {
    auto next = cursor.advance();
    switch (next.Kind) {
    case llvm::BitstreamEntry::EndBlock:
      return true;

    case llvm::BitstreamEntry::Error:
      return false;

    case llvm::BitstreamEntry::SubBlock:
      // Unknown sub-block, which this version of the compiler won't use.
      if (cursor.SkipBlock())
        return false;
      break;

    case llvm::BitstreamEntry::Record:
      scratch.clear();
      blobData = {};
      unsigned kind = cursor.readRecord(next.ID, scratch, &blobData);

      switch (kind) {
      case index_block::DECL_OFFSETS:
        assert(blobData.empty());
        Decls.assign(scratch.begin(), scratch.end());
        break;
      case index_block::DECL_CONTEXT_OFFSETS:
        assert(blobData.empty());
        DeclContexts.assign(scratch.begin(), scratch.end());
        break;
      case index_block::TYPE_OFFSETS:
        assert(blobData.empty());
        Types.assign(scratch.begin(), scratch.end());
        break;
      case index_block::IDENTIFIER_OFFSETS:
        assert(blobData.empty());
        Identifiers.assign(scratch.begin(), scratch.end());
        break;
      case index_block::TOP_LEVEL_DECLS:
        TopLevelDecls = readDeclTable(scratch, blobData);
        break;
      case index_block::OPERATORS:
        OperatorDecls = readDeclTable(scratch, blobData);
        break;
      case index_block::EXTENSIONS:
        ExtensionDecls = readDeclTable(scratch, blobData);
        break;
      case index_block::CLASS_MEMBERS:
        ClassMembersByName = readDeclTable(scratch, blobData);
        break;
      case index_block::OPERATOR_METHODS:
        OperatorMethodDecls = readDeclTable(scratch, blobData);
        break;
      case index_block::OBJC_METHODS:
        ObjCMethods = readObjCMethodTable(scratch, blobData);
        break;
      case index_block::ENTRY_POINT:
        assert(blobData.empty());
        setEntryPointClassID(scratch.front());
        break;
      case index_block::LOCAL_TYPE_DECLS:
        LocalTypeDecls = readLocalDeclTable(scratch, blobData);
        break;
      case index_block::LOCAL_DECL_CONTEXT_OFFSETS:
        assert(blobData.empty());
        LocalDeclContexts.assign(scratch.begin(), scratch.end());
        break;
      case index_block::NORMAL_CONFORMANCE_OFFSETS:
        assert(blobData.empty());
        NormalConformances.assign(scratch.begin(), scratch.end());
        break;

      default:
        // Unknown index kind, which this version of the compiler won't use.
        break;
      }
      break;
    }
  }
}
Example #16
0
Value* LoopTripCount::insertTripCount(Loop* L, Instruction* InsertPos)
{
	// inspired from Loop::getCanonicalInductionVariable
	BasicBlock *H = L->getHeader();
	BasicBlock* LoopPred = L->getLoopPredecessor();
	BasicBlock* startBB = NULL;//which basicblock stores start value
	int OneStep = 0;// the extra add or plus step for calc

   Assert(LoopPred, "Require Loop has a Pred");
	DEBUG(errs()<<"loop  depth:"<<L->getLoopDepth()<<"\n");
	/** whats difference on use of predecessor and preheader??*/
	//RET_ON_FAIL(self->getLoopLatch()&&self->getLoopPreheader());
	//assert(self->getLoopLatch() && self->getLoopPreheader() && "need loop simplify form" );
	ret_null_fail(L->getLoopLatch(), "need loop simplify form");

	BasicBlock* TE = NULL;//True Exit
	SmallVector<BasicBlock*,4> Exits;
	L->getExitingBlocks(Exits);

	if(Exits.size()==1) TE = Exits.front();
	else{
		if(std::find(Exits.begin(),Exits.end(),L->getLoopLatch())!=Exits.end()) TE = L->getLoopLatch();
		else{
			SmallVector<llvm::Loop::Edge,4> ExitEdges;
			L->getExitEdges(ExitEdges);
			//stl 用法,先把所有满足条件的元素(出口的结束符是不可到达)移动到数组的末尾,再统一删除
			ExitEdges.erase(std::remove_if(ExitEdges.begin(), ExitEdges.end(), 
						[](llvm::Loop::Edge& I){
						return isa<UnreachableInst>(I.second->getTerminator());
						}), ExitEdges.end());
			if(ExitEdges.size()==1) TE = const_cast<BasicBlock*>(ExitEdges.front().first);
		}
	}

	//process true exit
	ret_null_fail(TE, "need have a true exit");

	Instruction* IndOrNext = NULL;
	Value* END = NULL;
   //终止块的终止指令:分情况讨论branchinst,switchinst;
   //跳转指令br bool a1,a2;condition<-->bool
	if(isa<BranchInst>(TE->getTerminator())){
		const BranchInst* EBR = cast<BranchInst>(TE->getTerminator());
		Assert(EBR->isConditional(), "end branch is not conditional");
		ICmpInst* EC = dyn_cast<ICmpInst>(EBR->getCondition());
		if(EC->getPredicate() == EC->ICMP_SGT){
         Assert(!L->contains(EBR->getSuccessor(0)), *EBR<<":abnormal exit with great than");//终止块的终止指令---->跳出执行循环外的指令
         OneStep += 1;
      } else if(EC->getPredicate() == EC->ICMP_EQ)
         Assert(!L->contains(EBR->getSuccessor(0)), *EBR<<":abnormal exit with great than");
      else if(EC->getPredicate() == EC->ICMP_SLT) {
         ret_null_fail(!L->contains(EBR->getSuccessor(1)), *EBR<<":abnormal exit with less than");
      } else {
         ret_null_fail(0, *EC<<" unknow combination of end condition");
      }
		IndOrNext = dyn_cast<Instruction>(castoff(EC->getOperand(0)));//去掉类型转化
		END = EC->getOperand(1);
		DEBUG(errs()<<"end   value:"<<*EC<<"\n");
	}else if(isa<SwitchInst>(TE->getTerminator())){
		SwitchInst* ESW = const_cast<SwitchInst*>(cast<SwitchInst>(TE->getTerminator()));
		IndOrNext = dyn_cast<Instruction>(castoff(ESW->getCondition()));
		for(auto I = ESW->case_begin(),E = ESW->case_end();I!=E;++I){
			if(!L->contains(I.getCaseSuccessor())){
				ret_null_fail(!END,"");
				assert(!END && "shouldn't have two ends");
				END = I.getCaseValue();
			}
		}
		DEBUG(errs()<<"end   value:"<<*ESW<<"\n");
	}else{
		assert(0 && "unknow terminator type");
	}

	ret_null_fail(L->isLoopInvariant(END), "end value should be loop invariant");//至此得END值

	Value* start = NULL;
	Value* ind = NULL;
	Instruction* next = NULL;
	bool addfirst = false;//add before icmp ed

	DISABLE(errs()<<*IndOrNext<<"\n");
	if(isa<LoadInst>(IndOrNext)){
		//memory depend analysis
		Value* PSi = IndOrNext->getOperand(0);//point type Step.i

		int SICount[2] = {0};//store in predecessor count,store in loop body count
		for( auto I = PSi->use_begin(),E = PSi->use_end();I!=E;++I){
			DISABLE(errs()<<**I<<"\n");
			StoreInst* SI = dyn_cast<StoreInst>(*I);
			if(!SI || SI->getOperand(1) != PSi) continue;
			if(!start&&L->isLoopInvariant(SI->getOperand(0))) {
				if(SI->getParent() != LoopPred)
					if(std::find(pred_begin(LoopPred),pred_end(LoopPred),SI->getParent()) == pred_end(LoopPred)) continue;
				start = SI->getOperand(0);
				startBB = SI->getParent();
				++SICount[0];
			}
			Instruction* SI0 = dyn_cast<Instruction>(SI->getOperand(0));
			if(L->contains(SI) && SI0 && SI0->getOpcode() == Instruction::Add){
				next = SI0;
				++SICount[1];
			}

		}
		Assert(SICount[0]==1 && SICount[1]==1, "");
		ind = IndOrNext;
	}else{
		if(isa<PHINode>(IndOrNext)){
			PHINode* PHI = cast<PHINode>(IndOrNext);
			ind = IndOrNext;
			if(castoff(PHI->getIncomingValue(0)) == castoff(PHI->getIncomingValue(1)) && PHI->getParent() != H)
				ind = castoff(PHI->getIncomingValue(0));
			addfirst = false;
		}else if(IndOrNext->getOpcode() == Instruction::Add){
			next = IndOrNext;
			addfirst = true;
		}else{
			Assert(0 ,"unknow how to analysis");
		}

		for(auto I = H->begin();isa<PHINode>(I);++I){
			PHINode* P = cast<PHINode>(I);
			if(ind && P == ind){
				//start = P->getIncomingValueForBlock(L->getLoopPredecessor());
				start = tryFindStart(P, L, startBB);
				next = dyn_cast<Instruction>(P->getIncomingValueForBlock(L->getLoopLatch()));
			}else if(next && P->getIncomingValueForBlock(L->getLoopLatch()) == next){
				//start = P->getIncomingValueForBlock(L->getLoopPredecessor());
				start = tryFindStart(P, L, startBB);
				ind = P;
			}
		}
	}


	Assert(start ,"couldn't find a start value");
	//process complex loops later
	//DEBUG(if(L->getLoopDepth()>1 || !L->getSubLoops().empty()) return NULL);
	DEBUG(errs()<<"start value:"<<*start<<"\n");
	DEBUG(errs()<<"ind   value:"<<*ind<<"\n");
	DEBUG(errs()<<"next  value:"<<*next<<"\n");


	//process non add later
	unsigned next_phi_idx = 0;
	ConstantInt* Step = NULL,*PrevStep = NULL;/*only used if next is phi node*/
   ret_null_fail(next, "");
	PHINode* next_phi = dyn_cast<PHINode>(next);
	do{
		if(next_phi) {
			next = dyn_cast<Instruction>(next_phi->getIncomingValue(next_phi_idx));
			ret_null_fail(next, "");
			DEBUG(errs()<<"next phi "<<next_phi_idx<<":"<<*next<<"\n");
			if(Step&&PrevStep){
				Assert(Step->getSExtValue() == PrevStep->getSExtValue(),"");
			}
			PrevStep = Step;
		}
		Assert(next->getOpcode() == Instruction::Add , "why induction increment is not Add");
		Assert(next->getOperand(0) == ind ,"why induction increment is not add it self");
		Step = dyn_cast<ConstantInt>(next->getOperand(1));
		Assert(Step,"");
	}while(next_phi && ++next_phi_idx<next_phi->getNumIncomingValues());
	//RET_ON_FAIL(Step->equalsInt(1));
	//assert(VERBOSE(Step->equalsInt(1),Step) && "why induction increment number is not 1");


	Value* RES = NULL;
	//if there are no predecessor, we can insert code into start value basicblock
	IRBuilder<> Builder(InsertPos);
	Assert(start->getType()->isIntegerTy() && END->getType()->isIntegerTy() , " why increment is not integer type");
	if(start->getType() != END->getType()){
		start = Builder.CreateCast(CastInst::getCastOpcode(start, false,
					END->getType(), false),start,END->getType());
	}
   if(Step->getType() != END->getType()){
      //Because Step is a Constant, so it casted is constant
		Step = dyn_cast<ConstantInt>(Builder.CreateCast(CastInst::getCastOpcode(Step, false,
					END->getType(), false),Step,END->getType()));
      AssertRuntime(Step);
   }
	if(Step->isMinusOne())
		RES = Builder.CreateSub(start,END);
	else//Step Couldn't be zero
		RES = Builder.CreateSub(END, start);
	if(addfirst) OneStep -= 1;
	if(Step->isMinusOne()) OneStep*=-1;
	assert(OneStep<=1 && OneStep>=-1);
	RES = (OneStep==1)?Builder.CreateAdd(RES,Step):(OneStep==-1)?Builder.CreateSub(RES, Step):RES;
	if(!Step->isMinusOne()&&!Step->isOne())
		RES = Builder.CreateSDiv(RES, Step);
	RES->setName(H->getName()+".tc");

	return RES;
}
Example #17
0
bool GuardWideningImpl::combineRangeChecks(
    SmallVectorImpl<GuardWideningImpl::RangeCheck> &Checks,
    SmallVectorImpl<GuardWideningImpl::RangeCheck> &RangeChecksOut) {
  unsigned OldCount = Checks.size();
  while (!Checks.empty()) {
    // Pick all of the range checks with a specific base and length, and try to
    // merge them.
    Value *CurrentBase = Checks.front().getBase();
    Value *CurrentLength = Checks.front().getLength();

    SmallVector<GuardWideningImpl::RangeCheck, 3> CurrentChecks;

    auto IsCurrentCheck = [&](GuardWideningImpl::RangeCheck &RC) {
      return RC.getBase() == CurrentBase && RC.getLength() == CurrentLength;
    };

    copy_if(Checks, std::back_inserter(CurrentChecks), IsCurrentCheck);
    Checks.erase(remove_if(Checks, IsCurrentCheck), Checks.end());

    assert(CurrentChecks.size() != 0 && "We know we have at least one!");

    if (CurrentChecks.size() < 3) {
      RangeChecksOut.insert(RangeChecksOut.end(), CurrentChecks.begin(),
                            CurrentChecks.end());
      continue;
    }

    // CurrentChecks.size() will typically be 3 here, but so far there has been
    // no need to hard-code that fact.

    std::sort(CurrentChecks.begin(), CurrentChecks.end(),
              [&](const GuardWideningImpl::RangeCheck &LHS,
                  const GuardWideningImpl::RangeCheck &RHS) {
      return LHS.getOffsetValue().slt(RHS.getOffsetValue());
    });

    // Note: std::sort should not invalidate the ChecksStart iterator.

    ConstantInt *MinOffset = CurrentChecks.front().getOffset(),
                *MaxOffset = CurrentChecks.back().getOffset();

    unsigned BitWidth = MaxOffset->getValue().getBitWidth();
    if ((MaxOffset->getValue() - MinOffset->getValue())
            .ugt(APInt::getSignedMinValue(BitWidth)))
      return false;

    APInt MaxDiff = MaxOffset->getValue() - MinOffset->getValue();
    const APInt &HighOffset = MaxOffset->getValue();
    auto OffsetOK = [&](const GuardWideningImpl::RangeCheck &RC) {
      return (HighOffset - RC.getOffsetValue()).ult(MaxDiff);
    };

    if (MaxDiff.isMinValue() ||
        !std::all_of(std::next(CurrentChecks.begin()), CurrentChecks.end(),
                     OffsetOK))
      return false;

    // We have a series of f+1 checks as:
    //
    //   I+k_0 u< L   ... Chk_0
    //   I_k_1 u< L   ... Chk_1
    //   ...
    //   I_k_f u< L   ... Chk_(f+1)
    //
    //     with forall i in [0,f): k_f-k_i u< k_f-k_0  ... Precond_0
    //          k_f-k_0 u< INT_MIN+k_f                 ... Precond_1
    //          k_f != k_0                             ... Precond_2
    //
    // Claim:
    //   Chk_0 AND Chk_(f+1)  implies all the other checks
    //
    // Informal proof sketch:
    //
    // We will show that the integer range [I+k_0,I+k_f] does not unsigned-wrap
    // (i.e. going from I+k_0 to I+k_f does not cross the -1,0 boundary) and
    // thus I+k_f is the greatest unsigned value in that range.
    //
    // This combined with Ckh_(f+1) shows that everything in that range is u< L.
    // Via Precond_0 we know that all of the indices in Chk_0 through Chk_(f+1)
    // lie in [I+k_0,I+k_f], this proving our claim.
    //
    // To see that [I+k_0,I+k_f] is not a wrapping range, note that there are
    // two possibilities: I+k_0 u< I+k_f or I+k_0 >u I+k_f (they can't be equal
    // since k_0 != k_f).  In the former case, [I+k_0,I+k_f] is not a wrapping
    // range by definition, and the latter case is impossible:
    //
    //   0-----I+k_f---I+k_0----L---INT_MAX,INT_MIN------------------(-1)
    //   xxxxxx             xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    //
    // For Chk_0 to succeed, we'd have to have k_f-k_0 (the range highlighted
    // with 'x' above) to be at least >u INT_MIN.

    RangeChecksOut.emplace_back(CurrentChecks.front());
    RangeChecksOut.emplace_back(CurrentChecks.back());
  }

  assert(RangeChecksOut.size() <= OldCount && "We pessimized!");
  return RangeChecksOut.size() != OldCount;
}
Example #18
0
Instruction *InstCombiner::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
  Value *LHS = SVI.getOperand(0);
  Value *RHS = SVI.getOperand(1);
  SmallVector<int, 16> Mask = SVI.getShuffleMask();
  Type *Int32Ty = Type::getInt32Ty(SVI.getContext());

  bool MadeChange = false;

  // Undefined shuffle mask -> undefined value.
  if (isa<UndefValue>(SVI.getOperand(2)))
    return replaceInstUsesWith(SVI, UndefValue::get(SVI.getType()));

  unsigned VWidth = cast<VectorType>(SVI.getType())->getNumElements();

  APInt UndefElts(VWidth, 0);
  APInt AllOnesEltMask(APInt::getAllOnesValue(VWidth));
  if (Value *V = SimplifyDemandedVectorElts(&SVI, AllOnesEltMask, UndefElts)) {
    if (V != &SVI)
      return replaceInstUsesWith(SVI, V);
    LHS = SVI.getOperand(0);
    RHS = SVI.getOperand(1);
    MadeChange = true;
  }

  unsigned LHSWidth = cast<VectorType>(LHS->getType())->getNumElements();

  // Canonicalize shuffle(x    ,x,mask) -> shuffle(x, undef,mask')
  // Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask').
  if (LHS == RHS || isa<UndefValue>(LHS)) {
    if (isa<UndefValue>(LHS) && LHS == RHS) {
      // shuffle(undef,undef,mask) -> undef.
      Value *Result = (VWidth == LHSWidth)
                      ? LHS : UndefValue::get(SVI.getType());
      return replaceInstUsesWith(SVI, Result);
    }

    // Remap any references to RHS to use LHS.
    SmallVector<Constant*, 16> Elts;
    for (unsigned i = 0, e = LHSWidth; i != VWidth; ++i) {
      if (Mask[i] < 0) {
        Elts.push_back(UndefValue::get(Int32Ty));
        continue;
      }

      if ((Mask[i] >= (int)e && isa<UndefValue>(RHS)) ||
          (Mask[i] <  (int)e && isa<UndefValue>(LHS))) {
        Mask[i] = -1;     // Turn into undef.
        Elts.push_back(UndefValue::get(Int32Ty));
      } else {
        Mask[i] = Mask[i] % e;  // Force to LHS.
        Elts.push_back(ConstantInt::get(Int32Ty, Mask[i]));
      }
    }
    SVI.setOperand(0, SVI.getOperand(1));
    SVI.setOperand(1, UndefValue::get(RHS->getType()));
    SVI.setOperand(2, ConstantVector::get(Elts));
    LHS = SVI.getOperand(0);
    RHS = SVI.getOperand(1);
    MadeChange = true;
  }

  if (VWidth == LHSWidth) {
    // Analyze the shuffle, are the LHS or RHS and identity shuffles?
    bool isLHSID, isRHSID;
    recognizeIdentityMask(Mask, isLHSID, isRHSID);

    // Eliminate identity shuffles.
    if (isLHSID) return replaceInstUsesWith(SVI, LHS);
    if (isRHSID) return replaceInstUsesWith(SVI, RHS);
  }

  if (isa<UndefValue>(RHS) && CanEvaluateShuffled(LHS, Mask)) {
    Value *V = EvaluateInDifferentElementOrder(LHS, Mask);
    return replaceInstUsesWith(SVI, V);
  }

  // SROA generates shuffle+bitcast when the extracted sub-vector is bitcast to
  // a non-vector type. We can instead bitcast the original vector followed by
  // an extract of the desired element:
  //
  //   %sroa = shufflevector <16 x i8> %in, <16 x i8> undef,
  //                         <4 x i32> <i32 0, i32 1, i32 2, i32 3>
  //   %1 = bitcast <4 x i8> %sroa to i32
  // Becomes:
  //   %bc = bitcast <16 x i8> %in to <4 x i32>
  //   %ext = extractelement <4 x i32> %bc, i32 0
  //
  // If the shuffle is extracting a contiguous range of values from the input
  // vector then each use which is a bitcast of the extracted size can be
  // replaced. This will work if the vector types are compatible, and the begin
  // index is aligned to a value in the casted vector type. If the begin index
  // isn't aligned then we can shuffle the original vector (keeping the same
  // vector type) before extracting.
  //
  // This code will bail out if the target type is fundamentally incompatible
  // with vectors of the source type.
  //
  // Example of <16 x i8>, target type i32:
  // Index range [4,8):         v-----------v Will work.
  //                +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
  //     <16 x i8>: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
  //     <4 x i32>: |           |           |           |           |
  //                +-----------+-----------+-----------+-----------+
  // Index range [6,10):              ^-----------^ Needs an extra shuffle.
  // Target type i40:           ^--------------^ Won't work, bail.
  if (isShuffleExtractingFromLHS(SVI, Mask)) {
    Value *V = LHS;
    unsigned MaskElems = Mask.size();
    unsigned BegIdx = Mask.front();
    VectorType *SrcTy = cast<VectorType>(V->getType());
    unsigned VecBitWidth = SrcTy->getBitWidth();
    unsigned SrcElemBitWidth = DL.getTypeSizeInBits(SrcTy->getElementType());
    assert(SrcElemBitWidth && "vector elements must have a bitwidth");
    unsigned SrcNumElems = SrcTy->getNumElements();
    SmallVector<BitCastInst *, 8> BCs;
    DenseMap<Type *, Value *> NewBCs;
    for (User *U : SVI.users())
      if (BitCastInst *BC = dyn_cast<BitCastInst>(U))
        if (!BC->use_empty())
          // Only visit bitcasts that weren't previously handled.
          BCs.push_back(BC);
    for (BitCastInst *BC : BCs) {
      Type *TgtTy = BC->getDestTy();
      unsigned TgtElemBitWidth = DL.getTypeSizeInBits(TgtTy);
      if (!TgtElemBitWidth)
        continue;
      unsigned TgtNumElems = VecBitWidth / TgtElemBitWidth;
      bool VecBitWidthsEqual = VecBitWidth == TgtNumElems * TgtElemBitWidth;
      bool BegIsAligned = 0 == ((SrcElemBitWidth * BegIdx) % TgtElemBitWidth);
      if (!VecBitWidthsEqual)
        continue;
      if (!VectorType::isValidElementType(TgtTy))
        continue;
      VectorType *CastSrcTy = VectorType::get(TgtTy, TgtNumElems);
      if (!BegIsAligned) {
        // Shuffle the input so [0,NumElements) contains the output, and
        // [NumElems,SrcNumElems) is undef.
        SmallVector<Constant *, 16> ShuffleMask(SrcNumElems,
                                                UndefValue::get(Int32Ty));
        for (unsigned I = 0, E = MaskElems, Idx = BegIdx; I != E; ++Idx, ++I)
          ShuffleMask[I] = ConstantInt::get(Int32Ty, Idx);
        V = Builder->CreateShuffleVector(V, UndefValue::get(V->getType()),
                                         ConstantVector::get(ShuffleMask),
                                         SVI.getName() + ".extract");
        BegIdx = 0;
      }
      unsigned SrcElemsPerTgtElem = TgtElemBitWidth / SrcElemBitWidth;
      assert(SrcElemsPerTgtElem);
      BegIdx /= SrcElemsPerTgtElem;
      bool BCAlreadyExists = NewBCs.find(CastSrcTy) != NewBCs.end();
      auto *NewBC =
          BCAlreadyExists
              ? NewBCs[CastSrcTy]
              : Builder->CreateBitCast(V, CastSrcTy, SVI.getName() + ".bc");
      if (!BCAlreadyExists)
        NewBCs[CastSrcTy] = NewBC;
      auto *Ext = Builder->CreateExtractElement(
          NewBC, ConstantInt::get(Int32Ty, BegIdx), SVI.getName() + ".extract");
      // The shufflevector isn't being replaced: the bitcast that used it
      // is. InstCombine will visit the newly-created instructions.
      replaceInstUsesWith(*BC, Ext);
      MadeChange = true;
    }
  }

  // If the LHS is a shufflevector itself, see if we can combine it with this
  // one without producing an unusual shuffle.
  // Cases that might be simplified:
  // 1.
  // x1=shuffle(v1,v2,mask1)
  //  x=shuffle(x1,undef,mask)
  //        ==>
  //  x=shuffle(v1,undef,newMask)
  // newMask[i] = (mask[i] < x1.size()) ? mask1[mask[i]] : -1
  // 2.
  // x1=shuffle(v1,undef,mask1)
  //  x=shuffle(x1,x2,mask)
  // where v1.size() == mask1.size()
  //        ==>
  //  x=shuffle(v1,x2,newMask)
  // newMask[i] = (mask[i] < x1.size()) ? mask1[mask[i]] : mask[i]
  // 3.
  // x2=shuffle(v2,undef,mask2)
  //  x=shuffle(x1,x2,mask)
  // where v2.size() == mask2.size()
  //        ==>
  //  x=shuffle(x1,v2,newMask)
  // newMask[i] = (mask[i] < x1.size())
  //              ? mask[i] : mask2[mask[i]-x1.size()]+x1.size()
  // 4.
  // x1=shuffle(v1,undef,mask1)
  // x2=shuffle(v2,undef,mask2)
  //  x=shuffle(x1,x2,mask)
  // where v1.size() == v2.size()
  //        ==>
  //  x=shuffle(v1,v2,newMask)
  // newMask[i] = (mask[i] < x1.size())
  //              ? mask1[mask[i]] : mask2[mask[i]-x1.size()]+v1.size()
  //
  // Here we are really conservative:
  // we are absolutely afraid of producing a shuffle mask not in the input
  // program, because the code gen may not be smart enough to turn a merged
  // shuffle into two specific shuffles: it may produce worse code.  As such,
  // we only merge two shuffles if the result is either a splat or one of the
  // input shuffle masks.  In this case, merging the shuffles just removes
  // one instruction, which we know is safe.  This is good for things like
  // turning: (splat(splat)) -> splat, or
  // merge(V[0..n], V[n+1..2n]) -> V[0..2n]
  ShuffleVectorInst* LHSShuffle = dyn_cast<ShuffleVectorInst>(LHS);
  ShuffleVectorInst* RHSShuffle = dyn_cast<ShuffleVectorInst>(RHS);
  if (LHSShuffle)
    if (!isa<UndefValue>(LHSShuffle->getOperand(1)) && !isa<UndefValue>(RHS))
      LHSShuffle = nullptr;
  if (RHSShuffle)
    if (!isa<UndefValue>(RHSShuffle->getOperand(1)))
      RHSShuffle = nullptr;
  if (!LHSShuffle && !RHSShuffle)
    return MadeChange ? &SVI : nullptr;

  Value* LHSOp0 = nullptr;
  Value* LHSOp1 = nullptr;
  Value* RHSOp0 = nullptr;
  unsigned LHSOp0Width = 0;
  unsigned RHSOp0Width = 0;
  if (LHSShuffle) {
    LHSOp0 = LHSShuffle->getOperand(0);
    LHSOp1 = LHSShuffle->getOperand(1);
    LHSOp0Width = cast<VectorType>(LHSOp0->getType())->getNumElements();
  }
  if (RHSShuffle) {
    RHSOp0 = RHSShuffle->getOperand(0);
    RHSOp0Width = cast<VectorType>(RHSOp0->getType())->getNumElements();
  }
  Value* newLHS = LHS;
  Value* newRHS = RHS;
  if (LHSShuffle) {
    // case 1
    if (isa<UndefValue>(RHS)) {
      newLHS = LHSOp0;
      newRHS = LHSOp1;
    }
    // case 2 or 4
    else if (LHSOp0Width == LHSWidth) {
      newLHS = LHSOp0;
    }
  }
  // case 3 or 4
  if (RHSShuffle && RHSOp0Width == LHSWidth) {
    newRHS = RHSOp0;
  }
  // case 4
  if (LHSOp0 == RHSOp0) {
    newLHS = LHSOp0;
    newRHS = nullptr;
  }

  if (newLHS == LHS && newRHS == RHS)
    return MadeChange ? &SVI : nullptr;

  SmallVector<int, 16> LHSMask;
  SmallVector<int, 16> RHSMask;
  if (newLHS != LHS)
    LHSMask = LHSShuffle->getShuffleMask();
  if (RHSShuffle && newRHS != RHS)
    RHSMask = RHSShuffle->getShuffleMask();

  unsigned newLHSWidth = (newLHS != LHS) ? LHSOp0Width : LHSWidth;
  SmallVector<int, 16> newMask;
  bool isSplat = true;
  int SplatElt = -1;
  // Create a new mask for the new ShuffleVectorInst so that the new
  // ShuffleVectorInst is equivalent to the original one.
  for (unsigned i = 0; i < VWidth; ++i) {
    int eltMask;
    if (Mask[i] < 0) {
      // This element is an undef value.
      eltMask = -1;
    } else if (Mask[i] < (int)LHSWidth) {
      // This element is from left hand side vector operand.
      //
      // If LHS is going to be replaced (case 1, 2, or 4), calculate the
      // new mask value for the element.
      if (newLHS != LHS) {
        eltMask = LHSMask[Mask[i]];
        // If the value selected is an undef value, explicitly specify it
        // with a -1 mask value.
        if (eltMask >= (int)LHSOp0Width && isa<UndefValue>(LHSOp1))
          eltMask = -1;
      } else
        eltMask = Mask[i];
    } else {
      // This element is from right hand side vector operand
      //
      // If the value selected is an undef value, explicitly specify it
      // with a -1 mask value. (case 1)
      if (isa<UndefValue>(RHS))
        eltMask = -1;
      // If RHS is going to be replaced (case 3 or 4), calculate the
      // new mask value for the element.
      else if (newRHS != RHS) {
        eltMask = RHSMask[Mask[i]-LHSWidth];
        // If the value selected is an undef value, explicitly specify it
        // with a -1 mask value.
        if (eltMask >= (int)RHSOp0Width) {
          assert(isa<UndefValue>(RHSShuffle->getOperand(1))
                 && "should have been check above");
          eltMask = -1;
        }
      } else
        eltMask = Mask[i]-LHSWidth;

      // If LHS's width is changed, shift the mask value accordingly.
      // If newRHS == NULL, i.e. LHSOp0 == RHSOp0, we want to remap any
      // references from RHSOp0 to LHSOp0, so we don't need to shift the mask.
      // If newRHS == newLHS, we want to remap any references from newRHS to
      // newLHS so that we can properly identify splats that may occur due to
      // obfuscation across the two vectors.
      if (eltMask >= 0 && newRHS != nullptr && newLHS != newRHS)
        eltMask += newLHSWidth;
    }

    // Check if this could still be a splat.
    if (eltMask >= 0) {
      if (SplatElt >= 0 && SplatElt != eltMask)
        isSplat = false;
      SplatElt = eltMask;
    }

    newMask.push_back(eltMask);
  }

  // If the result mask is equal to one of the original shuffle masks,
  // or is a splat, do the replacement.
  if (isSplat || newMask == LHSMask || newMask == RHSMask || newMask == Mask) {
    SmallVector<Constant*, 16> Elts;
    for (unsigned i = 0, e = newMask.size(); i != e; ++i) {
      if (newMask[i] < 0) {
        Elts.push_back(UndefValue::get(Int32Ty));
      } else {
        Elts.push_back(ConstantInt::get(Int32Ty, newMask[i]));
      }
    }
    if (!newRHS)
      newRHS = UndefValue::get(newLHS->getType());
    return new ShuffleVectorInst(newLHS, newRHS, ConstantVector::get(Elts));
  }

  // If the result mask is an identity, replace uses of this instruction with
  // corresponding argument.
  bool isLHSID, isRHSID;
  recognizeIdentityMask(newMask, isLHSID, isRHSID);
  if (isLHSID && VWidth == LHSOp0Width) return replaceInstUsesWith(SVI, newLHS);
  if (isRHSID && VWidth == RHSOp0Width) return replaceInstUsesWith(SVI, newRHS);

  return MadeChange ? &SVI : nullptr;
}