Do not waste space for the fast-case elements backing storage for ...

src/x64/codegen-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2406 matching lines @@
 
   // Load the literals array of the function.
   __ movq(literals.reg(),
           FieldOperand(literals.reg(), JSFunction::kLiteralsOffset));
   // Literal array.
   frame_->Push(&literals);
   // Literal index.
   frame_->Push(Smi::FromInt(node->literal_index()));
   // Constant properties.
   frame_->Push(node->constant_properties());
+  // Should the object literal have fast elements?
+  frame_->Push(Smi::FromInt(node->fast_elements() ? 1 : 0));
   Result clone;
   if (node->depth() > 1) {
-    clone = frame_->CallRuntime(Runtime::kCreateObjectLiteral, 3);
+    clone = frame_->CallRuntime(Runtime::kCreateObjectLiteral, 4);
   } else {
-    clone = frame_->CallRuntime(Runtime::kCreateObjectLiteralShallow, 3);
+    clone = frame_->CallRuntime(Runtime::kCreateObjectLiteralShallow, 4);
   }
   frame_->Push(&clone);
 
   for (int i = 0; i < node->properties()->length(); i++) {
     ObjectLiteral::Property* property = node->properties()->at(i);
     switch (property->kind()) {
       case ObjectLiteral::Property::CONSTANT:
         break;
       case ObjectLiteral::Property::MATERIALIZED_LITERAL:
         if (CompileTimeValue::IsCompileTimeValue(property->value())) break;
@@ skipping 7354 matching lines @@
   // Call the function from C++.
   return FUNCTION_CAST<ModuloFunction>(buffer);
 }
 
 #endif
 
 
 #undef __
 
 } }  // namespace v8::internal