Index: include/clang/AST/Expr.h
===================================================================
--- include/clang/AST/Expr.h
+++ include/clang/AST/Expr.h
@@ -2405,8 +2405,6 @@
 class CallExpr : public Expr {
   enum { FN=0, PREARGS_START=1 };
   Stmt **SubExprs;
-  unsigned NumArgs;
-  SourceLocation RParenLoc;
 
   void updateDependenciesFromArg(Expr *Arg);
 
@@ -2458,8 +2456,7 @@
   }
 
   /// getNumArgs - Return the number of actual arguments to this call.
-  ///
-  unsigned getNumArgs() const { return NumArgs; }
+  unsigned getNumArgs() const { return CallExprBits.NumArgs; }
 
   /// Retrieve the call arguments.
   Expr **getArgs() {
@@ -2472,17 +2469,17 @@
 
   /// getArg - Return the specified argument.
   Expr *getArg(unsigned Arg) {
-    assert(Arg < NumArgs && "Arg access out of range!");
+    assert(Arg < getNumArgs() && "Arg access out of range!");
     return cast_or_null<Expr>(SubExprs[Arg + getNumPreArgs() + PREARGS_START]);
   }
   const Expr *getArg(unsigned Arg) const {
-    assert(Arg < NumArgs && "Arg access out of range!");
+    assert(Arg < getNumArgs() && "Arg access out of range!");
     return cast_or_null<Expr>(SubExprs[Arg + getNumPreArgs() + PREARGS_START]);
   }
 
   /// setArg - Set the specified argument.
   void setArg(unsigned Arg, Expr *ArgExpr) {
-    assert(Arg < NumArgs && "Arg access out of range!");
+    assert(Arg < getNumArgs() && "Arg access out of range!");
     SubExprs[Arg+getNumPreArgs()+PREARGS_START] = ArgExpr;
   }
 
@@ -2523,7 +2520,7 @@
 
   /// getNumCommas - Return the number of commas that must have been present in
   /// this function call.
-  unsigned getNumCommas() const { return NumArgs ? NumArgs - 1 : 0; }
+  unsigned getNumCommas() const { return getNumArgs() ? getNumArgs() - 1 : 0; }
 
   /// getBuiltinCallee - If this is a call to a builtin, return the builtin ID
   /// of the callee. If not, return 0.
@@ -2538,8 +2535,8 @@
   /// type.
   QualType getCallReturnType(const ASTContext &Ctx) const;
 
-  SourceLocation getRParenLoc() const { return RParenLoc; }
-  void setRParenLoc(SourceLocation L) { RParenLoc = L; }
+  SourceLocation getRParenLoc() const { return CallExprBits.RParenLoc; }
+  void setRParenLoc(SourceLocation L) { CallExprBits.RParenLoc = L; }
 
   SourceLocation getBeginLoc() const LLVM_READONLY;
   SourceLocation getEndLoc() const LLVM_READONLY;
@@ -2561,12 +2558,12 @@
 
   // Iterators
   child_range children() {
-    return child_range(&SubExprs[0],
-                       &SubExprs[0]+NumArgs+getNumPreArgs()+PREARGS_START);
+    return child_range(&SubExprs[0], &SubExprs[0] + getNumArgs() +
+                                         getNumPreArgs() + PREARGS_START);
   }
 
   const_child_range children() const {
-    return const_child_range(&SubExprs[0], &SubExprs[0] + NumArgs +
+    return const_child_range(&SubExprs[0], &SubExprs[0] + getNumArgs() +
                                                getNumPreArgs() + PREARGS_START);
   }
 };
Index: include/clang/AST/Stmt.h
===================================================================
--- include/clang/AST/Stmt.h
+++ include/clang/AST/Stmt.h
@@ -422,6 +422,9 @@
     unsigned : NumExprBits;
 
     unsigned NumPreArgs : 1;
+    unsigned NumArgs : 14;
+
+    SourceLocation RParenLoc;
   };
 
   class MemberExprBitfields {
Index: lib/AST/Expr.cpp
===================================================================
--- lib/AST/Expr.cpp
+++ lib/AST/Expr.cpp
@@ -1225,23 +1225,26 @@
                    ExprValueKind VK, SourceLocation rparenloc)
     : Expr(SC, t, VK, OK_Ordinary, fn->isTypeDependent(),
            fn->isValueDependent(), fn->isInstantiationDependent(),
-           fn->containsUnexpandedParameterPack()),
-      NumArgs(args.size()) {
+           fn->containsUnexpandedParameterPack()) {
+  unsigned NumArgs = args.size();
+  CallExprBits.NumArgs = NumArgs;
+  assert((getNumArgs() == NumArgs) && "NumArgs overflow!");
 
   unsigned NumPreArgs = preargs.size();
-  SubExprs = new (C) Stmt *[args.size()+PREARGS_START+NumPreArgs];
+  CallExprBits.NumPreArgs = NumPreArgs;
+
+  SubExprs = new (C) Stmt *[NumArgs+PREARGS_START+NumPreArgs];
   SubExprs[FN] = fn;
   for (unsigned i = 0; i != NumPreArgs; ++i) {
     updateDependenciesFromArg(preargs[i]);
     SubExprs[i+PREARGS_START] = preargs[i];
   }
-  for (unsigned i = 0; i != args.size(); ++i) {
+  for (unsigned i = 0; i != NumArgs; ++i) {
     updateDependenciesFromArg(args[i]);
     SubExprs[i+PREARGS_START+NumPreArgs] = args[i];
   }
 
-  CallExprBits.NumPreArgs = NumPreArgs;
-  RParenLoc = rparenloc;
+  setRParenLoc(rparenloc);
 }
 
 CallExpr::CallExpr(const ASTContext &C, StmtClass SC, Expr *fn,
@@ -1259,7 +1262,8 @@
 
 CallExpr::CallExpr(const ASTContext &C, StmtClass SC, unsigned NumPreArgs,
                    EmptyShell Empty)
-  : Expr(SC, Empty), SubExprs(nullptr), NumArgs(0) {
+  : Expr(SC, Empty), SubExprs(nullptr) {
+  CallExprBits.NumArgs = 0;
   // FIXME: Why do we allocate this?
   SubExprs = new (C) Stmt*[PREARGS_START+NumPreArgs]();
   CallExprBits.NumPreArgs = NumPreArgs;
@@ -1317,7 +1321,7 @@
 
   // If shrinking # arguments, just delete the extras and forgot them.
   if (NumArgs < getNumArgs()) {
-    this->NumArgs = NumArgs;
+    CallExprBits.NumArgs = NumArgs;
     return;
   }
 
@@ -1334,7 +1338,7 @@
 
   if (SubExprs) C.Deallocate(SubExprs);
   SubExprs = NewSubExprs;
-  this->NumArgs = NumArgs;
+  CallExprBits.NumArgs = NumArgs;
 }
 
 /// getBuiltinCallee - If this is a call to a builtin, return the builtin ID. If