diff --git a/clang/lib/AST/ExprObjC.cpp b/clang/lib/AST/ExprObjC.cpp
@@ -39,16 +39,14 @@ ObjCArrayLiteral *ObjCArrayLiteral::Create(const ASTContext &C,
                                            ArrayRef<Expr *> Elements,
                                            QualType T, ObjCMethodDecl *Method,
                                            SourceRange SR) {
-  void *Mem =
-      C.Allocate(sizeof(ObjCArrayLiteral) + Elements.size() * sizeof(Expr *));
+  void *Mem = C.Allocate(totalSizeToAlloc<Expr *>(Elements.size()));
   return new (Mem) ObjCArrayLiteral(Elements, T, Method, SR);
 }
 
 ObjCArrayLiteral *ObjCArrayLiteral::CreateEmpty(const ASTContext &C,
                                                 unsigned NumElements) {
 
-  void *Mem =
-      C.Allocate(sizeof(ObjCArrayLiteral) + NumElements * sizeof(Expr *));
+  void *Mem = C.Allocate(totalSizeToAlloc<Expr *>(NumElements));
   return new (Mem) ObjCArrayLiteral(EmptyShell(), NumElements);
 }
 
@@ -60,8 +58,8 @@ ObjCDictionaryLiteral::ObjCDictionaryLiteral(ArrayRef<ObjCDictionaryElement> VK,
            false, false),
       NumElements(VK.size()), HasPackExpansions(HasPackExpansions), Range(SR),
       DictWithObjectsMethod(method) {
-  KeyValuePair *KeyValues = getKeyValues();
-  ExpansionData *Expansions = getExpansionData();
+  KeyValuePair *KeyValues = getTrailingObjects<KeyValuePair>();
+  ExpansionData *Expansions = getTrailingObjects<ExpansionData>();
   for (unsigned I = 0; I < NumElements; I++) {
     if (VK[I].Key->isTypeDependent() || VK[I].Key->isValueDependent() ||
         VK[I].Value->isTypeDependent() || VK[I].Value->isValueDependent())
@@ -91,23 +89,16 @@ ObjCDictionaryLiteral::Create(const ASTContext &C,
                               ArrayRef<ObjCDictionaryElement> VK,
                               bool HasPackExpansions, QualType T,
                               ObjCMethodDecl *method, SourceRange SR) {
-  unsigned ExpansionsSize = 0;
-  if (HasPackExpansions)
-    ExpansionsSize = sizeof(ExpansionData) * VK.size();
-
-  void *Mem = C.Allocate(sizeof(ObjCDictionaryLiteral) +
-                         sizeof(KeyValuePair) * VK.size() + ExpansionsSize);
+  void *Mem = C.Allocate(totalSizeToAlloc<KeyValuePair, ExpansionData>(
+      VK.size(), HasPackExpansions ? VK.size() : 0));
   return new (Mem) ObjCDictionaryLiteral(VK, HasPackExpansions, T, method, SR);
 }
 
 ObjCDictionaryLiteral *
 ObjCDictionaryLiteral::CreateEmpty(const ASTContext &C, unsigned NumElements,
                                    bool HasPackExpansions) {
-  unsigned ExpansionsSize = 0;
-  if (HasPackExpansions)
-    ExpansionsSize = sizeof(ExpansionData) * NumElements;
-  void *Mem = C.Allocate(sizeof(ObjCDictionaryLiteral) +
-                         sizeof(KeyValuePair) * NumElements + ExpansionsSize);
+  void *Mem = C.Allocate(totalSizeToAlloc<KeyValuePair, ExpansionData>(
+      NumElements, HasPackExpansions ? NumElements : 0));
   return new (Mem)
       ObjCDictionaryLiteral(EmptyShell(), NumElements, HasPackExpansions);
 }
@@ -122,15 +113,6 @@ QualType ObjCPropertyRefExpr::getReceiverType(const ASTContext &ctx) const {
   return getBase()->getType();
 }
 
-ObjCSubscriptRefExpr *
-ObjCSubscriptRefExpr::Create(const ASTContext &C, Expr *base, Expr *key,
-                             QualType T, ObjCMethodDecl *getMethod,
-                             ObjCMethodDecl *setMethod, SourceLocation RB) {
-  void *Mem = C.Allocate(sizeof(ObjCSubscriptRefExpr));
-  return new (Mem) ObjCSubscriptRefExpr(
-      base, key, T, VK_LValue, OK_ObjCSubscript, getMethod, setMethod, RB);
-}
-
 ObjCMessageExpr::ObjCMessageExpr(QualType T, ExprValueKind VK,
                                  SourceLocation LBracLoc,
                                  SourceLocation SuperLoc, bool IsInstanceSuper,
@@ -293,11 +275,9 @@ ObjCMessageExpr *ObjCMessageExpr::alloc(const ASTContext &C,
 
 ObjCMessageExpr *ObjCMessageExpr::alloc(const ASTContext &C, unsigned NumArgs,
                                         unsigned NumStoredSelLocs) {
-  unsigned Size = sizeof(ObjCMessageExpr) + sizeof(void *) +
-                  NumArgs * sizeof(Expr *) +
-                  NumStoredSelLocs * sizeof(SourceLocation);
   return (ObjCMessageExpr *)C.Allocate(
-      Size, llvm::AlignOf<ObjCMessageExpr>::Alignment);
+      totalSizeToAlloc<void *, SourceLocation>(NumArgs + 1, NumStoredSelLocs),
+      llvm::AlignOf<ObjCMessageExpr>::Alignment);
 }
 
 void ObjCMessageExpr::getSelectorLocs(
@@ -358,7 +338,7 @@ ObjCInterfaceDecl *ObjCMessageExpr::getReceiverInterface() const {
 Stmt::child_range ObjCMessageExpr::children() {
   Stmt **begin;
   if (getReceiverKind() == Instance)
-    begin = reinterpret_cast<Stmt **>(this + 1);
+    begin = reinterpret_cast<Stmt **>(getTrailingObjects<void *>());
   else
     begin = reinterpret_cast<Stmt **>(getArgs());
   return child_range(begin,

diff --git a/clang/lib/Sema/SemaExprObjC.cpp b/clang/lib/Sema/SemaExprObjC.cpp
@@ -756,9 +756,9 @@ ExprResult Sema::BuildObjCSubscriptExpression(SourceLocation RB, Expr *BaseExpr,
   BaseExpr = Result.get();
 
   // Build the pseudo-object expression.
-  return ObjCSubscriptRefExpr::Create(Context, BaseExpr, IndexExpr,
-                                      Context.PseudoObjectTy, getterMethod,
-                                      setterMethod, RB);
+  return new (Context) ObjCSubscriptRefExpr(
+      BaseExpr, IndexExpr, Context.PseudoObjectTy, VK_LValue, OK_ObjCSubscript,
+      getterMethod, setterMethod, RB);
 }
 
 ExprResult Sema::BuildObjCArrayLiteral(SourceRange SR, MultiExprArg Elements) {

diff --git a/clang/lib/Serialization/ASTReaderStmt.cpp b/clang/lib/Serialization/ASTReaderStmt.cpp
@@ -987,8 +987,10 @@ void ASTStmtReader::VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
   assert(NumElements == E->getNumElements() && "Wrong number of elements");
   bool HasPackExpansions = Record[Idx++];
   assert(HasPackExpansions == E->HasPackExpansions &&"Pack expansion mismatch");
-  ObjCDictionaryLiteral::KeyValuePair *KeyValues = E->getKeyValues();
-  ObjCDictionaryLiteral::ExpansionData *Expansions = E->getExpansionData();
+  ObjCDictionaryLiteral::KeyValuePair *KeyValues =
+      E->getTrailingObjects<ObjCDictionaryLiteral::KeyValuePair>();
+  ObjCDictionaryLiteral::ExpansionData *Expansions =
+      E->getTrailingObjects<ObjCDictionaryLiteral::ExpansionData>();
   for (unsigned I = 0; I != NumElements; ++I) {
     KeyValues[I].Key = Reader.ReadSubExpr();
     KeyValues[I].Value = Reader.ReadSubExpr();