Revert change to always call builtins for Array functions....

src/x64/stub-cache-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 741 matching lines @@
         // Check that the maps starting from the prototype haven't changed.
         GenerateLoadGlobalFunctionPrototype(masm(),
                                             Context::BOOLEAN_FUNCTION_INDEX,
                                             rax);
         CheckPrototypes(JSObject::cast(object->GetPrototype()), rax, holder,
                         rbx, rdx, name, &miss);
       }
       break;
     }
 
+    case JSARRAY_HAS_FAST_ELEMENTS_CHECK:
+      CheckPrototypes(JSObject::cast(object), rdx, holder,
+                      rbx, rax, name, &miss);
+      // Make sure object->HasFastElements().
+      // Get the elements array of the object.
+      __ movq(rbx, FieldOperand(rdx, JSObject::kElementsOffset));
+      // Check that the object is in fast mode (not dictionary).
+      __ Cmp(FieldOperand(rbx, HeapObject::kMapOffset),
+             Factory::fixed_array_map());
+      __ j(not_equal, &miss);
+      break;
+
     default:
       UNREACHABLE();
   }
 
   __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
 
   // Handle call cache miss.
   __ bind(&miss);
   Handle<Code> ic = ComputeCallMiss(arguments().immediate());
   __ Jump(ic, RelocInfo::CODE_TARGET);
@@ skipping 1069 matching lines @@
   __ Jump(generic_construct_stub, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal