[C++11] Replacing DeclBase iterators decls_begin() and decls_end() with iterator_range decls(). The same is true for the noload versions of these APIs. Updating all of the usages of the iterators with range-based for loops.

llvm-svn: 203278

21 files changed, 129 insertions, 186 deletions

diff --git a/clang/include/clang/AST/DataRecursiveASTVisitor.h b/clang/include/clang/AST/DataRecursiveASTVisitor.h
index f3481c15bfe..46e1cde7da8 100644
--- a/clang/include/clang/AST/DataRecursiveASTVisitor.h
+++ b/clang/include/clang/AST/DataRecursiveASTVisitor.h
@@ -1222,13 +1222,11 @@ bool DataRecursiveASTVisitor<Derived>::TraverseDeclContextHelper(DeclContext *DC
   if (!DC)
     return true;
 
-  for (DeclContext::decl_iterator Child = DC->decls_begin(),
-           ChildEnd = DC->decls_end();
-       Child != ChildEnd; ++Child) {
+  for (auto *Child : DC->decls()) {
     // BlockDecls and CapturedDecls are traversed through BlockExprs and
     // CapturedStmts respectively.
-    if (!isa<BlockDecl>(*Child) && !isa<CapturedDecl>(*Child))
-      TRY_TO(TraverseDecl(*Child));
+    if (!isa<BlockDecl>(Child) && !isa<CapturedDecl>(Child))
+      TRY_TO(TraverseDecl(Child));
   }
 
   return true;
diff --git a/clang/include/clang/AST/DeclBase.h b/clang/include/clang/AST/DeclBase.h
index 957e2b719e9..47a3600e9ca 100644
--- a/clang/include/clang/AST/DeclBase.h
+++ b/clang/include/clang/AST/DeclBase.h
@@ -1306,17 +1306,21 @@ public:
     }
   };
 
+  typedef llvm::iterator_range<decl_iterator> decl_range;
+
   /// decls_begin/decls_end - Iterate over the declarations stored in
   /// this context.
-  decl_iterator decls_begin() const;
-  decl_iterator decls_end() const { return decl_iterator(); }
+  decl_range decls() const;
+  decl_iterator decls_begin() const { return decls().begin(); }
+  decl_iterator decls_end() const { return decls().end(); }
   bool decls_empty() const;
 
   /// noload_decls_begin/end - Iterate over the declarations stored in this
   /// context that are currently loaded; don't attempt to retrieve anything
   /// from an external source.
-  decl_iterator noload_decls_begin() const;
-  decl_iterator noload_decls_end() const { return decl_iterator(); }
+  decl_range noload_decls() const;
+  decl_iterator noload_decls_begin() const { return noload_decls().begin(); }
+  decl_iterator noload_decls_end() const { return noload_decls().end(); }
 
   /// specific_decl_iterator - Iterates over a subrange of
   /// declarations stored in a DeclContext, providing only those that
diff --git a/clang/include/clang/AST/RecursiveASTVisitor.h b/clang/include/clang/AST/RecursiveASTVisitor.h
index 92c26c4235b..cf0b7e51bb5 100644
--- a/clang/include/clang/AST/RecursiveASTVisitor.h
+++ b/clang/include/clang/AST/RecursiveASTVisitor.h
@@ -1303,13 +1303,11 @@ bool RecursiveASTVisitor<Derived>::TraverseDeclContextHelper(DeclContext *DC) {
   if (!DC)
     return true;
 
-  for (DeclContext::decl_iterator Child = DC->decls_begin(),
-           ChildEnd = DC->decls_end();
-       Child != ChildEnd; ++Child) {
+  for (auto *Child : DC->decls()) {
     // BlockDecls and CapturedDecls are traversed through BlockExprs and
     // CapturedStmts respectively.
-    if (!isa<BlockDecl>(*Child) && !isa<CapturedDecl>(*Child))
-      TRY_TO(TraverseDecl(*Child));
+    if (!isa<BlockDecl>(Child) && !isa<CapturedDecl>(Child))
+      TRY_TO(TraverseDecl(Child));
   }
 
   return true;
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index ca029899335..9f3387664ca 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -930,10 +930,8 @@ static Optional<unsigned> findAnonymousStructOrUnionIndex(RecordDecl *Anon) {
     return None;
 
   unsigned Index = 0;
-  for (DeclContext::decl_iterator D = Owner->noload_decls_begin(),
-                               DEnd = Owner->noload_decls_end();
-       D != DEnd; ++D) {
-    FieldDecl *F = dyn_cast<FieldDecl>(*D);
+  for (const auto *D : Owner->noload_decls()) {
+    const auto *F = dyn_cast<FieldDecl>(D);
     if (!F || !F->isAnonymousStructOrUnion())
       continue;
 
@@ -1908,11 +1906,8 @@ void ASTNodeImporter::ImportDeclContext(DeclContext *FromDC, bool ForceImport) {
     return;
   }
   
-  for (DeclContext::decl_iterator From = FromDC->decls_begin(),
-                               FromEnd = FromDC->decls_end();
-       From != FromEnd;
-       ++From)
-    Importer.Import(*From);
+  for (auto *From : FromDC->decls())
+    Importer.Import(From);
 }
 
 bool ASTNodeImporter::ImportDefinition(RecordDecl *From, RecordDecl *To, 
@@ -2852,10 +2847,8 @@ static unsigned getFieldIndex(Decl *F) {
     return 0;
 
   unsigned Index = 1;
-  for (DeclContext::decl_iterator D = Owner->noload_decls_begin(),
-                               DEnd = Owner->noload_decls_end();
-       D != DEnd; ++D) {
-    if (*D == F)
+  for (const auto *D : Owner->noload_decls()) {
+    if (D == F)
       return Index;
 
     if (isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D))
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 2c4df114755..711946ea009 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -1076,15 +1076,14 @@ ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
   return List.getLookupResult();
 }
 
-DeclContext::decl_iterator DeclContext::noload_decls_begin() const {
-  return decl_iterator(FirstDecl);
+DeclContext::decl_range DeclContext::noload_decls() const {
+  return decl_range(decl_iterator(FirstDecl), decl_iterator());
 }
 
-DeclContext::decl_iterator DeclContext::decls_begin() const {
+DeclContext::decl_range DeclContext::decls() const {
   if (hasExternalLexicalStorage())
     LoadLexicalDeclsFromExternalStorage();
-
-  return decl_iterator(FirstDecl);
+  return decl_range(decl_iterator(FirstDecl), decl_iterator());
 }
 
 bool DeclContext::decls_empty() const {
diff --git a/clang/lib/Analysis/CallGraph.cpp b/clang/lib/Analysis/CallGraph.cpp
index 24705e534b5..649ba57bf58 100644
--- a/clang/lib/Analysis/CallGraph.cpp
+++ b/clang/lib/Analysis/CallGraph.cpp
@@ -95,9 +95,8 @@ void CallGraph::addNodesForBlocks(DeclContext *D) {
   if (BlockDecl *BD = dyn_cast<BlockDecl>(D))
     addNodeForDecl(BD, true);
 
-  for (DeclContext::decl_iterator I = D->decls_begin(), E = D->decls_end();
-       I!=E; ++I)
-    if (DeclContext *DC = dyn_cast<DeclContext>(*I))
+  for (auto *I : D->decls())
+    if (auto *DC = dyn_cast<DeclContext>(I))
       addNodesForBlocks(DC);
 }
 
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 761876988ac..d115f264ba7 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -935,9 +935,8 @@ void CGDebugInfo::CollectRecordFields(const RecordDecl *record,
 
     // Static and non-static members should appear in the same order as
     // the corresponding declarations in the source program.
-    for (RecordDecl::decl_iterator I = record->decls_begin(),
-           E = record->decls_end(); I != E; ++I)
-      if (const VarDecl *V = dyn_cast<VarDecl>(*I)) {
+    for (const auto *I : record->decls())
+      if (const auto *V = dyn_cast<VarDecl>(I)) {
         // Reuse the existing static member declaration if one exists
         llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator MI =
             StaticDataMemberCache.find(V->getCanonicalDecl());
@@ -948,7 +947,7 @@ void CGDebugInfo::CollectRecordFields(const RecordDecl *record,
               llvm::DIDerivedType(cast<llvm::MDNode>(MI->second)));
         } else
           elements.push_back(CreateRecordStaticField(V, RecordTy));
-      } else if (FieldDecl *field = dyn_cast<FieldDecl>(*I)) {
+      } else if (const auto *field = dyn_cast<FieldDecl>(I)) {
         CollectRecordNormalField(field, layout.getFieldOffset(fieldNo),
                                  tunit, elements, RecordTy);
 
@@ -1130,9 +1129,8 @@ CollectCXXMemberFunctions(const CXXRecordDecl *RD, llvm::DIFile Unit,
   // Since we want more than just the individual member decls if we
   // have templated functions iterate over every declaration to gather
   // the functions.
-  for(DeclContext::decl_iterator I = RD->decls_begin(),
-        E = RD->decls_end(); I != E; ++I) {
-    if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*I)) {
+  for(const auto *I : RD->decls()) {
+    if (const auto *Method = dyn_cast<CXXMethodDecl>(I)) {
       // Reuse the existing member function declaration if it exists.
       // It may be associated with the declaration of the type & should be
       // reused as we're building the definition.
@@ -1149,8 +1147,7 @@ CollectCXXMemberFunctions(const CXXRecordDecl *RD, llvm::DIFile Unit,
           EltTys.push_back(CreateCXXMemberFunction(Method, Unit, RecordTy));
       } else
         EltTys.push_back(MI->second);
-    } else if (const FunctionTemplateDecl *FTD =
-                   dyn_cast<FunctionTemplateDecl>(*I)) {
+    } else if (const auto *FTD = dyn_cast<FunctionTemplateDecl>(I)) {
       // Add any template specializations that have already been seen. Like
       // implicit member functions, these may have been added to a declaration
       // in the case of vtable-based debug info reduction.
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 9b3e32952e1..a5cd9e34af5 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2832,13 +2832,12 @@ void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
 
 /// EmitNamespace - Emit all declarations in a namespace.
 void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) {
-  for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end();
-       I != E; ++I) {
-    if (const VarDecl *VD = dyn_cast<VarDecl>(*I))
+  for (auto *I : ND->decls()) {
+    if (const auto *VD = dyn_cast<VarDecl>(I))
       if (VD->getTemplateSpecializationKind() != TSK_ExplicitSpecialization &&
           VD->getTemplateSpecializationKind() != TSK_Undeclared)
         continue;
-    EmitTopLevelDecl(*I);
+    EmitTopLevelDecl(I);
   }
 }
 
@@ -2850,17 +2849,16 @@ void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
     return;
   }
 
-  for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end();
-       I != E; ++I) {
+  for (auto *I : LSD->decls()) {
     // Meta-data for ObjC class includes references to implemented methods.
     // Generate class's method definitions first.
-    if (ObjCImplDecl *OID = dyn_cast<ObjCImplDecl>(*I)) {
+    if (auto *OID = dyn_cast<ObjCImplDecl>(I)) {
       for (ObjCContainerDecl::method_iterator M = OID->meth_begin(),
            MEnd = OID->meth_end();
            M != MEnd; ++M)
         EmitTopLevelDecl(*M);
     }
-    EmitTopLevelDecl(*I);
+    EmitTopLevelDecl(I);
   }
 }
 
diff --git a/clang/lib/CodeGen/ModuleBuilder.cpp b/clang/lib/CodeGen/ModuleBuilder.cpp
index a51abf03d5c..d54a4a8186f 100644
--- a/clang/lib/CodeGen/ModuleBuilder.cpp
+++ b/clang/lib/CodeGen/ModuleBuilder.cpp
@@ -93,10 +93,8 @@ namespace {
       // In C++, we may have member functions that need to be emitted at this 
       // point.
       if (Ctx->getLangOpts().CPlusPlus && !D->isDependentContext()) {
-        for (DeclContext::decl_iterator M = D->decls_begin(), 
-                                     MEnd = D->decls_end();
-             M != MEnd; ++M)
-          if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(*M))
+        for (auto *M : D->decls())
+          if (auto *Method = dyn_cast<CXXMethodDecl>(M))
             if (Method->doesThisDeclarationHaveABody() &&
                 (Method->hasAttr<UsedAttr>() || 
                  Method->hasAttr<ConstructorAttr>()))
diff --git a/clang/lib/Frontend/ASTConsumers.cpp b/clang/lib/Frontend/ASTConsumers.cpp
index 44a84f70e88..aee8cd71675 100644
--- a/clang/lib/Frontend/ASTConsumers.cpp
+++ b/clang/lib/Frontend/ASTConsumers.cpp
@@ -368,8 +368,7 @@ void DeclContextPrinter::PrintDeclContext(const DeclContext* DC,
   Out << "\n";
 
   // Print decls in the DeclContext.
-  for (DeclContext::decl_iterator I = DC->decls_begin(), E = DC->decls_end();
-       I != E; ++I) {
+  for (auto *I : DC->decls()) {
     for (unsigned i = 0; i < Indentation; ++i)
       Out << "  ";
 
@@ -393,58 +392,58 @@ void DeclContextPrinter::PrintDeclContext(const DeclContext* DC,
     case Decl::CXXDestructor:
     case Decl::CXXConversion:
     {
-      DeclContext* DC = cast<DeclContext>(*I);
+      DeclContext* DC = cast<DeclContext>(I);
       PrintDeclContext(DC, Indentation+2);
       break;
     }
     case Decl::IndirectField: {
-      IndirectFieldDecl* IFD = cast<IndirectFieldDecl>(*I);
+      IndirectFieldDecl* IFD = cast<IndirectFieldDecl>(I);
       Out << "<IndirectField> " << *IFD << '\n';
       break;
     }
     case Decl::Label: {
-      LabelDecl *LD = cast<LabelDecl>(*I);
+      LabelDecl *LD = cast<LabelDecl>(I);
       Out << "<Label> " << *LD << '\n';
       break;
     }
     case Decl::Field: {
-      FieldDecl *FD = cast<FieldDecl>(*I);
+      FieldDecl *FD = cast<FieldDecl>(I);
       Out << "<field> " << *FD << '\n';
       break;
     }
     case Decl::Typedef:
     case Decl::TypeAlias: {
-      TypedefNameDecl* TD = cast<TypedefNameDecl>(*I);
+      TypedefNameDecl* TD = cast<TypedefNameDecl>(I);
       Out << "<typedef> " << *TD << '\n';
       break;
     }
     case Decl::EnumConstant: {
-      EnumConstantDecl* ECD = cast<EnumConstantDecl>(*I);
+      EnumConstantDecl* ECD = cast<EnumConstantDecl>(I);
       Out << "<enum constant> " << *ECD << '\n';
       break;
     }
     case Decl::Var: {
-      VarDecl* VD = cast<VarDecl>(*I);
+      VarDecl* VD = cast<VarDecl>(I);
       Out << "<var> " << *VD << '\n';
       break;
     }
     case Decl::ImplicitParam: {
-      ImplicitParamDecl* IPD = cast<ImplicitParamDecl>(*I);
+      ImplicitParamDecl* IPD = cast<ImplicitParamDecl>(I);
       Out << "<implicit parameter> " << *IPD << '\n';
       break;
     }
     case Decl::ParmVar: {
-      ParmVarDecl* PVD = cast<ParmVarDecl>(*I);
+      ParmVarDecl* PVD = cast<ParmVarDecl>(I);
       Out << "<parameter> " << *PVD << '\n';
       break;
     }
     case Decl::ObjCProperty: {
-      ObjCPropertyDecl* OPD = cast<ObjCPropertyDecl>(*I);
+      ObjCPropertyDecl* OPD = cast<ObjCPropertyDecl>(I);
       Out << "<objc property> " << *OPD << '\n';
       break;
     }
     case Decl::FunctionTemplate: {
-      FunctionTemplateDecl* FTD = cast<FunctionTemplateDecl>(*I);
+      FunctionTemplateDecl* FTD = cast<FunctionTemplateDecl>(I);
       Out << "<function template> " << *FTD << '\n';
       break;
     }
@@ -457,21 +456,21 @@ void DeclContextPrinter::PrintDeclContext(const DeclContext* DC,
       break;
     }
     case Decl::NamespaceAlias: {
-      NamespaceAliasDecl* NAD = cast<NamespaceAliasDecl>(*I);
+      NamespaceAliasDecl* NAD = cast<NamespaceAliasDecl>(I);
       Out << "<namespace alias> " << *NAD << '\n';
       break;
     }
     case Decl::ClassTemplate: {
-      ClassTemplateDecl *CTD = cast<ClassTemplateDecl>(*I);
+      ClassTemplateDecl *CTD = cast<ClassTemplateDecl>(I);
       Out << "<class template> " << *CTD << '\n';
       break;
     }
     case Decl::OMPThreadPrivate: {
-      Out << "<omp threadprivate> " << '"' << *I << "\"\n";
+      Out << "<omp threadprivate> " << '"' << I << "\"\n";
       break;
     }
     default:
-      Out << "DeclKind: " << DK << '"' << *I << "\"\n";
+      Out << "DeclKind: " << DK << '"' << I << "\"\n";
       llvm_unreachable("decl unhandled");
     }
   }
diff --git a/clang/lib/Frontend/ASTMerge.cpp b/clang/lib/Frontend/ASTMerge.cpp
index b6c644eba78..ff6434c5694 100644
--- a/clang/lib/Frontend/ASTMerge.cpp
+++ b/clang/lib/Frontend/ASTMerge.cpp
@@ -57,16 +57,14 @@ void ASTMergeAction::ExecuteAction() {
                          /*MinimalImport=*/false);
 
     TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
-    for (DeclContext::decl_iterator D = TU->decls_begin(), 
-                                 DEnd = TU->decls_end();
-         D != DEnd; ++D) {
+    for (auto *D : TU->decls()) {
       // Don't re-import __va_list_tag, __builtin_va_list.
-      if (NamedDecl *ND = dyn_cast<NamedDecl>(*D))
+      if (const auto *ND = dyn_cast<NamedDecl>(D))
         if (IdentifierInfo *II = ND->getIdentifier())
           if (II->isStr("__va_list_tag") || II->isStr("__builtin_va_list"))
             continue;
       
-      Importer.Import(*D);
+      Importer.Import(D);
     }
 
     delete Unit;
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index ace3e9c6aad..a3ebd41a586 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -873,9 +873,8 @@ public:
   void handleFileLevelDecl(Decl *D) {
     Unit.addFileLevelDecl(D);
     if (NamespaceDecl *NSD = dyn_cast<NamespaceDecl>(D)) {
-      for (NamespaceDecl::decl_iterator
-             I = NSD->decls_begin(), E = NSD->decls_end(); I != E; ++I)
-        handleFileLevelDecl(*I);
+      for (auto *I : NSD->decls())
+        handleFileLevelDecl(I);
     }
   }
 
diff --git a/clang/lib/Sema/SemaAccess.cpp b/clang/lib/Sema/SemaAccess.cpp
index 66e6e644655..60c3e726e61 100644
--- a/clang/lib/Sema/SemaAccess.cpp
+++ b/clang/lib/Sema/SemaAccess.cpp
@@ -1138,11 +1138,9 @@ static void diagnoseBadDirectAccess(Sema &S,
   // Check whether there's an AccessSpecDecl preceding this in the
   // chain of the DeclContext.
   bool isImplicit = true;
-  for (CXXRecordDecl::decl_iterator
-         I = DeclaringClass->decls_begin(), E = DeclaringClass->decls_end();
-       I != E; ++I) {
-    if (*I == ImmediateChild) break;
-    if (isa<AccessSpecDecl>(*I)) {
+  for (const auto *I : DeclaringClass->decls()) {
+    if (I == ImmediateChild) break;
+    if (isa<AccessSpecDecl>(I)) {
       isImplicit = false;
       break;
     }
diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index b17031432fd..89310da648a 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -5731,11 +5731,9 @@ static void AddProtocolResults(DeclContext *Ctx, DeclContext *CurContext,
                                ResultBuilder &Results) {
   typedef CodeCompletionResult Result;
   
-  for (DeclContext::decl_iterator D = Ctx->decls_begin(), 
-                               DEnd = Ctx->decls_end();
-       D != DEnd; ++D) {
+  for (const auto *D : Ctx->decls()) {
     // Record any protocols we find.
-    if (ObjCProtocolDecl *Proto = dyn_cast<ObjCProtocolDecl>(*D))
+    if (const auto *Proto = dyn_cast<ObjCProtocolDecl>(D))
       if (!OnlyForwardDeclarations || !Proto->hasDefinition())
         Results.AddResult(Result(Proto, Results.getBasePriority(Proto), 0),
                           CurContext, 0, false);
@@ -5799,11 +5797,9 @@ static void AddInterfaceResults(DeclContext *Ctx, DeclContext *CurContext,
                                 ResultBuilder &Results) {
   typedef CodeCompletionResult Result;
   
-  for (DeclContext::decl_iterator D = Ctx->decls_begin(), 
-                               DEnd = Ctx->decls_end();
-       D != DEnd; ++D) {
+  for (const auto *D : Ctx->decls()) {
     // Record any interfaces we find.
-    if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(*D))
+    if (const auto *Class = dyn_cast<ObjCInterfaceDecl>(D))
       if ((!OnlyForwardDeclarations || !Class->hasDefinition()) &&
           (!OnlyUnimplemented || !Class->getImplementation()))
         Results.AddResult(Result(Class, Results.getBasePriority(Class), 0),
@@ -5901,10 +5897,8 @@ void Sema::CodeCompleteObjCInterfaceCategory(Scope *S,
   // Add all of the categories we know about.
   Results.EnterNewScope();
   TranslationUnitDecl *TU = Context.getTranslationUnitDecl();
-  for (DeclContext::decl_iterator D = TU->decls_begin(), 
-                               DEnd = TU->decls_end();
-       D != DEnd; ++D) 
-    if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(*D))
+  for (const auto *D : TU->decls()) 
+    if (const auto *Category = dyn_cast<ObjCCategoryDecl>(D))
       if (CategoryNames.insert(Category->getIdentifier()))
         Results.AddResult(Result(Category, Results.getBasePriority(Category),0),
                           CurContext, 0, false);
@@ -5975,10 +5969,8 @@ void Sema::CodeCompleteObjCPropertyDefinition(Scope *S) {
 
   // Ignore any properties that have already been implemented.
   Container = getContainerDef(Container);
-  for (DeclContext::decl_iterator D = Container->decls_begin(),
-                               DEnd = Container->decls_end();
-       D != DEnd; ++D)
-    if (ObjCPropertyImplDecl *PropertyImpl = dyn_cast<ObjCPropertyImplDecl>(*D))
+  for (const auto *D : Container->decls())
+    if (const auto *PropertyImpl = dyn_cast<ObjCPropertyImplDecl>(D))
       Results.Ignore(PropertyImpl->getPropertyDecl());
   
   // Add any properties that we find.
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 2ff2d8626ed..40eb1d5271f 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -3466,12 +3466,10 @@ static bool InjectAnonymousStructOrUnionMembers(Sema &SemaRef, Scope *S,
   bool Invalid = false;
 
   // Look every FieldDecl and IndirectFieldDecl with a name.
-  for (RecordDecl::decl_iterator D = AnonRecord->decls_begin(),
-                               DEnd = AnonRecord->decls_end();
-       D != DEnd; ++D) {
-    if ((isa<FieldDecl>(*D) || isa<IndirectFieldDecl>(*D)) &&
-        cast<NamedDecl>(*D)->getDeclName()) {
-      ValueDecl *VD = cast<ValueDecl>(*D);
+  for (auto *D : AnonRecord->decls()) {
+    if ((isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D)) &&
+        cast<NamedDecl>(D)->getDeclName()) {
+      ValueDecl *VD = cast<ValueDecl>(D);
       if (CheckAnonMemberRedeclaration(SemaRef, S, Owner, VD->getDeclName(),
                                        VD->getLocation(), diagKind)) {
         // C++ [class.union]p2:
@@ -3546,11 +3544,9 @@ StorageClassSpecToVarDeclStorageClass(const DeclSpec &DS) {
 static SourceLocation findDefaultInitializer(const CXXRecordDecl *Record) {
   assert(Record->hasInClassInitializer());
 
-  for (DeclContext::decl_iterator I = Record->decls_begin(),
-                                  E = Record->decls_end();
-       I != E; ++I) {
-    FieldDecl *FD = dyn_cast<FieldDecl>(*I);
-    if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(*I))
+  for (const auto *I : Record->decls()) {
+    const auto *FD = dyn_cast<FieldDecl>(I);
+    if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
       FD = IFD->getAnonField();
     if (FD && FD->hasInClassInitializer())
       return FD->getLocation();
@@ -3660,10 +3656,8 @@ Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
     //   The member-specification of an anonymous union shall only
     //   define non-static data members. [Note: nested types and
     //   functions cannot be declared within an anonymous union. ]
-    for (DeclContext::decl_iterator Mem = Record->decls_begin(),
-                                 MemEnd = Record->decls_end();
-         Mem != MemEnd; ++Mem) {
-      if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) {
+    for (auto *Mem : Record->decls()) {
+      if (auto *FD = dyn_cast<FieldDecl>(Mem)) {
         // C++ [class.union]p3:
         //   An anonymous union shall not have private or protected
         //   members (clause 11).
@@ -3681,14 +3675,14 @@ Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
         //   array of such objects.
         if (CheckNontrivialField(FD))
           Invalid = true;
-      } else if ((*Mem)->isImplicit()) {
+      } else if (Mem->isImplicit()) {
         // Any implicit members are fine.
-      } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) {
+      } else if (isa<TagDecl>(Mem) && Mem->getDeclContext() != Record) {
         // This is a type that showed up in an
         // elaborated-type-specifier inside the anonymous struct or
         // union, but which actually declares a type outside of the
         // anonymous struct or union. It's okay.
-      } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) {
+      } else if (auto *MemRecord = dyn_cast<RecordDecl>(Mem)) {
         if (!MemRecord->isAnonymousStructOrUnion() &&
             MemRecord->getDeclName()) {
           // Visual C++ allows type definition in anonymous struct or union.
@@ -3709,26 +3703,26 @@ Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
                diag::ext_anonymous_record_with_anonymous_type)
             << (int)Record->isUnion();
         }
-      } else if (isa<AccessSpecDecl>(*Mem)) {
+      } else if (isa<AccessSpecDecl>(Mem)) {
         // Any access specifier is fine.
       } else {
         // We have something that isn't a non-static data
         // member. Complain about it.
         unsigned DK = diag::err_anonymous_record_bad_member;
-        if (isa<TypeDecl>(*Mem))
+        if (isa<TypeDecl>(Mem))
           DK = diag::err_anonymous_record_with_type;
-        else if (isa<FunctionDecl>(*Mem))
+        else if (isa<FunctionDecl>(Mem))
           DK = diag::err_anonymous_record_with_function;
-        else if (isa<VarDecl>(*Mem))
+        else if (isa<VarDecl>(Mem))
           DK = diag::err_anonymous_record_with_static;
         
         // Visual C++ allows type definition in anonymous struct or union.
         if (getLangOpts().MicrosoftExt &&
             DK == diag::err_anonymous_record_with_type)
-          Diag((*Mem)->getLocation(), diag::ext_anonymous_record_with_type)
+          Diag(Mem->getLocation(), diag::ext_anonymous_record_with_type)
             << (int)Record->isUnion();
         else {
-          Diag((*Mem)->getLocation(), DK)
+          Diag(Mem->getLocation(), DK)
               << (int)Record->isUnion();
           Invalid = true;
         }
@@ -9620,9 +9614,8 @@ Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) {
       // and reattach to the current context.
       if (D->getLexicalDeclContext() == Context.getTranslationUnitDecl()) {
         // Is the decl actually in the context?
-        for (DeclContext::decl_iterator DI = Context.getTranslationUnitDecl()->decls_begin(),
-               DE = Context.getTranslationUnitDecl()->decls_end(); DI != DE; ++DI) {
-          if (*DI == D) {  
+        for (const auto *DI : Context.getTranslationUnitDecl()->decls()) {
+          if (DI == D) {  
             Context.getTranslationUnitDecl()->removeDecl(D);
             break;
           }
@@ -11880,9 +11873,8 @@ void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
   // members of anonymous structs and unions in the total.
   unsigned NumNamedMembers = 0;
   if (Record) {
-    for (RecordDecl::decl_iterator i = Record->decls_begin(),
-                                   e = Record->decls_end(); i != e; i++) {
-      if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(*i))
+    for (const auto *I : Record->decls()) {
+      if (const auto *IFD = dyn_cast<IndirectFieldDecl>(I))
         if (IFD->getDeclName())
           ++NumNamedMembers;
     }
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 54ba508383b..c373b46a510 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -2319,11 +2319,10 @@ namespace {
     llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
 
     // At the beginning, all fields are uninitialized.
-    for (DeclContext::decl_iterator I = RD->decls_begin(), E = RD->decls_end();
-         I != E; ++I) {
-      if (FieldDecl *FD = dyn_cast<FieldDecl>(*I)) {
+    for (auto *I : RD->decls()) {
+      if (auto *FD = dyn_cast<FieldDecl>(I)) {
         UninitializedFields.insert(FD);
-      } else if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(*I)) {
+      } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
         UninitializedFields.insert(IFD->getAnonField());
       }
     }
@@ -3645,10 +3644,8 @@ bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
   }
 
   // Fields.
-  for (DeclContext::decl_iterator Mem = ClassDecl->decls_begin(),
-                               MemEnd = ClassDecl->decls_end();
-       Mem != MemEnd; ++Mem) {
-    if (FieldDecl *F = dyn_cast<FieldDecl>(*Mem)) {
+  for (auto *Mem : ClassDecl->decls()) {
+    if (auto *F = dyn_cast<FieldDecl>(Mem)) {
       // C++ [class.bit]p2:
       //   A declaration for a bit-field that omits the identifier declares an
       //   unnamed bit-field. Unnamed bit-fields are not members and cannot be
@@ -3671,7 +3668,7 @@ bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
     if (Info.isImplicitCopyOrMove())
       continue;
     
-    if (IndirectFieldDecl *F = dyn_cast<IndirectFieldDecl>(*Mem)) {
+    if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
       if (F->getType()->isIncompleteArrayType()) {
         assert(ClassDecl->hasFlexibleArrayMember() &&
                "Incomplete array type is not valid");
@@ -4337,9 +4334,7 @@ static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
 /// Check for invalid uses of an abstract type within a class definition.
 static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
                                     CXXRecordDecl *RD) {
-  for (CXXRecordDecl::decl_iterator
-         I = RD->decls_begin(), E = RD->decls_end(); I != E; ++I) {
-    Decl *D = *I;
+  for (auto *D : RD->decls()) {
     if (D->isImplicit()) continue;
 
     // Methods and method templates.
@@ -6571,9 +6566,8 @@ static void DiagnoseNamespaceInlineMismatch(Sema &S, SourceLocation KeywordLoc,
       NS->setInline(*IsInline);
     // Patch up the lookup table for the containing namespace. This isn't really
     // correct, but it's good enough for this particular case.
-    for (DeclContext::decl_iterator I = PrevNS->decls_begin(),
-                                    E = PrevNS->decls_end(); I != E; ++I)
-      if (NamedDecl *ND = dyn_cast<NamedDecl>(*I))
+    for (auto *I : PrevNS->decls())
+      if (auto *ND = dyn_cast<NamedDecl>(I))
         PrevNS->getParent()->makeDeclVisibleInContext(ND);
     return;
   }
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 0fdf48ba74c..bef073080bf 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -2055,9 +2055,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
   LateInstantiatedAttrVec LateAttrs;
   Instantiator.enableLateAttributeInstantiation(&LateAttrs);
 
-  for (RecordDecl::decl_iterator Member = Pattern->decls_begin(),
-         MemberEnd = Pattern->decls_end();
-       Member != MemberEnd; ++Member) {
+  for (auto *Member : Pattern->decls()) {
     // Don't instantiate members not belonging in this semantic context.
     // e.g. for:
     // @code
@@ -2067,19 +2065,19 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
     // @endcode
     // 'class B' has the template as lexical context but semantically it is
     // introduced in namespace scope.
-    if ((*Member)->getDeclContext() != Pattern)
+    if (Member->getDeclContext() != Pattern)
       continue;
 
-    if ((*Member)->isInvalidDecl()) {
+    if (Member->isInvalidDecl()) {
       Instantiation->setInvalidDecl();
       continue;
     }
 
-    Decl *NewMember = Instantiator.Visit(*Member);
+    Decl *NewMember = Instantiator.Visit(Member);
     if (NewMember) {
       if (FieldDecl *Field = dyn_cast<FieldDecl>(NewMember)) {
         Fields.push_back(Field);
-        FieldDecl *OldField = cast<FieldDecl>(*Member);
+        FieldDecl *OldField = cast<FieldDecl>(Member);
         if (OldField->getInClassInitializer())
           FieldsWithMemberInitializers.push_back(std::make_pair(OldField,
                                                                 Field));
@@ -2471,11 +2469,9 @@ Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
        TSK == TSK_ExplicitInstantiationDeclaration ||
        (TSK == TSK_ImplicitInstantiation && Instantiation->isLocalClass())) &&
       "Unexpected template specialization kind!");
-  for (DeclContext::decl_iterator D = Instantiation->decls_begin(),
-                               DEnd = Instantiation->decls_end();
-       D != DEnd; ++D) {
+  for (auto *D : Instantiation->decls()) {
     bool SuppressNew = false;
-    if (FunctionDecl *Function = dyn_cast<FunctionDecl>(*D)) {
+    if (auto *Function = dyn_cast<FunctionDecl>(D)) {
       if (FunctionDecl *Pattern
             = Function->getInstantiatedFromMemberFunction()) {
         MemberSpecializationInfo *MSInfo 
@@ -2516,7 +2512,7 @@ Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
                 std::make_pair(Function, PointOfInstantiation));
         }
       }
-    } else if (VarDecl *Var = dyn_cast<VarDecl>(*D)) {
+    } else if (auto *Var = dyn_cast<VarDecl>(D)) {
       if (isa<VarTemplateSpecializationDecl>(Var))
         continue;
 
@@ -2552,7 +2548,7 @@ Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
           Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
         }
       }      
-    } else if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(*D)) {
+    } else if (auto *Record = dyn_cast<CXXRecordDecl>(D)) {
       // Always skip the injected-class-name, along with any
       // redeclarations of nested classes, since both would cause us
       // to try to instantiate the members of a class twice.
@@ -2609,7 +2605,7 @@ Sema::InstantiateClassMembers(SourceLocation PointOfInstantiation,
       if (Pattern)
         InstantiateClassMembers(PointOfInstantiation, Pattern, TemplateArgs, 
                                 TSK);
-    } else if (EnumDecl *Enum = dyn_cast<EnumDecl>(*D)) {
+    } else if (auto *Enum = dyn_cast<EnumDecl>(D)) {
       MemberSpecializationInfo *MSInfo = Enum->getMemberSpecializationInfo();
       assert(MSInfo && "No member specialization information?");
 
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 3e6b719bc6e..8c2eeca0215 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -2595,9 +2595,8 @@ uint64_t ASTWriter::WriteDeclContextLexicalBlock(ASTContext &Context,
   RecordData Record;
   Record.push_back(DECL_CONTEXT_LEXICAL);
   SmallVector<KindDeclIDPair, 64> Decls;
-  for (DeclContext::decl_iterator D = DC->decls_begin(), DEnd = DC->decls_end();
-         D != DEnd; ++D)
-    Decls.push_back(std::make_pair((*D)->getKind(), GetDeclRef(*D)));
+  for (const auto *D : DC->decls())
+    Decls.push_back(std::make_pair(D->getKind(), GetDeclRef(D)));
 
   ++NumLexicalDeclContexts;
   Stream.EmitRecordWithBlob(DeclContextLexicalAbbrev, Record, data(Decls));
@@ -4050,11 +4049,9 @@ void ASTWriter::WriteASTCore(Sema &SemaRef,
   // translation unit that do not come from other AST files.
   const TranslationUnitDecl *TU = Context.getTranslationUnitDecl();
   SmallVector<KindDeclIDPair, 64> NewGlobalDecls;
-  for (DeclContext::decl_iterator I = TU->noload_decls_begin(),
-                                  E = TU->noload_decls_end();
-       I != E; ++I) {
-    if (!(*I)->isFromASTFile())
-      NewGlobalDecls.push_back(std::make_pair((*I)->getKind(), GetDeclRef(*I)));
+  for (const auto *I : TU->noload_decls()) {
+    if (!I->isFromASTFile())
+      NewGlobalDecls.push_back(std::make_pair(I->getKind(), GetDeclRef(I)));
   }
   
   llvm::BitCodeAbbrev *Abv = new llvm::BitCodeAbbrev();
diff --git a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
index 606c734a309..1566d3c29b4 100644
--- a/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/ObjCUnusedIVarsChecker.cpp
@@ -101,9 +101,8 @@ static void Scan(IvarUsageMap& M, const ObjCContainerDecl *D) {
 
 static void Scan(IvarUsageMap &M, const DeclContext *C, const FileID FID,
                  SourceManager &SM) {
-  for (DeclContext::decl_iterator I=C->decls_begin(), E=C->decls_end();
-       I!=E; ++I)
-    if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) {
+  for (const auto *I : C->decls())
+    if (const auto *FD = dyn_cast<FunctionDecl>(I)) {
       SourceLocation L = FD->getLocStart();
       if (SM.getFileID(L) == FID)
         Scan(M, FD->getBody());
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index ac66a770db2..614bb0cbfc9 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -980,13 +980,11 @@ bool CursorVisitor::VisitObjCContainerDecl(ObjCContainerDecl *D) {
 
   // Get all the Decls in the DeclContext, and sort them with the
   // additional ones we've collected.  Then visit them.
-  for (DeclContext::decl_iterator I = D->decls_begin(), E = D->decls_end();
-       I!=E; ++I) {
-    Decl *subDecl = *I;
-    if (!subDecl || subDecl->getLexicalDeclContext() != D ||
-        subDecl->getLocStart().isInvalid())
+  for (auto *SubDecl : D->decls()) {
+    if (!SubDecl || SubDecl->getLexicalDeclContext() != D ||
+        SubDecl->getLocStart().isInvalid())
       continue;
-    DeclsInContainer.push_back(subDecl);
+    DeclsInContainer.push_back(SubDecl);
   }
 
   // Now sort the Decls so that they appear in lexical order.
diff --git a/clang/tools/libclang/IndexDecl.cpp b/clang/tools/libclang/IndexDecl.cpp
index d39076b974e..fbcd2d07a93 100644
--- a/clang/tools/libclang/IndexDecl.cpp
+++ b/clang/tools/libclang/IndexDecl.cpp
@@ -173,10 +173,9 @@ public:
            IvarE = D->ivar_end(); IvarI != IvarE; ++IvarI) {
       IndexCtx.indexDecl(*IvarI);
     }
-    for (DeclContext::decl_iterator
-           I = D->decls_begin(), E = D->decls_end(); I != E; ++I) {
-      if (!isa<ObjCIvarDecl>(*I))
-        IndexCtx.indexDecl(*I);
+    for (const auto *I : D->decls()) {
+      if (!isa<ObjCIvarDecl>(I))
+        IndexCtx.indexDecl(I);
     }
 
     return true;
@@ -337,10 +336,8 @@ void IndexingContext::indexDecl(const Decl *D) {
 }
 
 void IndexingContext::indexDeclContext(const DeclContext *DC) {
-  for (DeclContext::decl_iterator
-         I = DC->decls_begin(), E = DC->decls_end(); I != E; ++I) {
-    indexDecl(*I);
-  }
+  for (const auto *I : DC->decls())
+    indexDecl(I);
 }
 
 void IndexingContext::indexTopLevelDecl(const Decl *D) {