Make order of addition the primary order of descriptor arrays.

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 2148 matching lines @@
   NoHandleAllocation ha;
   RUNTIME_ASSERT(args.length() == 1);
   CONVERT_ARG_CHECKED(JSFunction, function, 0);
 
   String* name = isolate->heap()->prototype_symbol();
 
   if (function->HasFastProperties()) {
     // Construct a new field descriptor with updated attributes.
     DescriptorArray* instance_desc = function->map()->instance_descriptors();
 
-    int index = instance_desc->Search(name);
+    int index = instance_desc->SearchWithCache(name);
     ASSERT(index != DescriptorArray::kNotFound);
     PropertyDetails details = instance_desc->GetDetails(index);
 
     CallbacksDescriptor new_desc(name,
         instance_desc->GetValue(index),
         static_cast<PropertyAttributes>(details.attributes() | READ_ONLY),
-        details.index());
+        details.descriptor_index());
 
     // Create a new map featuring the new field descriptors array.
     Map* new_map;
     MaybeObject* maybe_map =
         function->map()->CopyReplaceDescriptor(
             &new_desc, index, OMIT_TRANSITION);
     if (!maybe_map->To(&new_map)) return maybe_map;
 
     function->set_map(new_map);
   } else {  // Dictionary properties.
     // Directly manipulate the property details.
     int entry = function->property_dictionary()->FindEntry(name);
     ASSERT(entry != StringDictionary::kNotFound);
     PropertyDetails details = function->property_dictionary()->DetailsAt(entry);
     PropertyDetails new_details(
         static_cast<PropertyAttributes>(details.attributes() | READ_ONLY),
         details.type(),
-        details.index());
+        details.dictionary_index());
     function->property_dictionary()->DetailsAtPut(entry, new_details);
   }
   return function;
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_FunctionIsAPIFunction) {
   NoHandleAllocation ha;
   ASSERT(args.length() == 1);
 
@@ skipping 8302 matching lines @@
   CONVERT_PROPERTY_DETAILS_CHECKED(details, 0);
   return Smi::FromInt(static_cast<int>(details.attributes()));
 }
 
 
 // Return the property insertion index calculated from the property details.
 // args[0]: smi with property details.
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DebugPropertyIndexFromDetails) {
   ASSERT(args.length() == 1);
   CONVERT_PROPERTY_DETAILS_CHECKED(details, 0);
-  return Smi::FromInt(details.index());
+  // TODO(verwaest): Depends on the type of details.
+  return Smi::FromInt(details.dictionary_index());
 }
 
 
 // Return property value from named interceptor.
 // args[0]: object
 // args[1]: property name
 RUNTIME_FUNCTION(MaybeObject*, Runtime_DebugNamedInterceptorPropertyValue) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
@@ skipping 3190 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