dom-query.html spends ~10% of total time in OSAtomicAdd32Barrier on my Mac

src/objects.h

 // Copyright 2012 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 1855 matching lines @@
       uint32_t index,
       Object* value,
       PropertyAttributes attributes,
       StrictModeFlag strict_mode,
       bool check_prototype = true,
       SetPropertyMode set_mode = SET_PROPERTY);
 
   // Returns the index'th element.
   // The undefined object if index is out of bounds.
   MUST_USE_RESULT MaybeObject* GetElementWithInterceptor(Object* receiver,
-                                                         uint32_t index);
+                                                         uint32_t index,
+                                                         Isolate* isolate);
 
   enum SetFastElementsCapacitySmiMode {
     kAllowSmiElements,
     kForceSmiElements,
     kDontAllowSmiElements
   };
 
   // Replace the elements' backing store with fast elements of the given
   // capacity.  Update the length for JSArrays.  Returns the new backing
   // store.
@@ skipping 7051 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_