Free up 11 bits in fast-mode PropertyDetails by removing the enumeration-index.

src/heap-snapshot-generator.cc

 // Copyright 2013 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 1291 matching lines @@
                              bindings->get(i));
     }
   }
 }
 
 
 void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj, int entry) {
   if (js_obj->HasFastProperties()) {
     DescriptorArray* descs = js_obj->map()->instance_descriptors();
     int real_size = js_obj->map()->NumberOfOwnDescriptors();
-    for (int i = 0; i < descs->number_of_descriptors(); i++) {
-      if (descs->GetDetails(i).descriptor_index() > real_size) continue;
+    for (int i = 0; i < real_size; i++) {
       switch (descs->GetType(i)) {
         case FIELD: {
           int index = descs->GetFieldIndex(i);
 
           Name* k = descs->GetKey(i);
           if (index < js_obj->map()->inobject_properties()) {
             Object* value = js_obj->InObjectPropertyAt(index);
             if (k != heap_->hidden_string()) {
               SetPropertyReference(
                   js_obj, entry,
@@ skipping 1335 matching lines @@
 
 
 void HeapSnapshotJSONSerializer::SortHashMap(
     HashMap* map, List<HashMap::Entry*>* sorted_entries) {
   for (HashMap::Entry* p = map->Start(); p != NULL; p = map->Next(p))
     sorted_entries->Add(p);
   sorted_entries->Sort(SortUsingEntryValue);
 }
 
 } }  // namespace v8::internal