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

src/runtime.cc

 // 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 10159 matching lines @@
 // Return element value from indexed interceptor.
 // args[0]: object
 // args[1]: index
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DebugIndexedInterceptorElementValue) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
   RUNTIME_ASSERT(obj->HasIndexedInterceptor());
   CONVERT_NUMBER_CHECKED(uint32_t, index, Uint32, args[1]);
 
-  return obj->GetElementWithInterceptor(*obj, index);
+  return obj->GetElementWithInterceptor(*obj, index, isolate);
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_CheckExecutionState) {
   ASSERT(args.length() >= 1);
   CONVERT_NUMBER_CHECKED(int, break_id, Int32, args[0]);
   // Check that the break id is valid.
   if (isolate->debug()->break_id() == 0 ||
       break_id != isolate->debug()->break_id()) {
     return isolate->Throw(
@@ skipping 3101 matching lines @@
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(Heap::kNoGCFlags,
                                        "Runtime::PerformGC");
   }
 }
 
 
 } }  // namespace v8::internal