Support fast case for-in in Crankshaft.

src/objects.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 5688 matching lines @@
   }
   result->set(kBitField3StorageIndex, Smi::FromInt(0));
   result->set(kContentArrayIndex, array);
   result->set(kEnumerationIndexIndex,
               Smi::FromInt(PropertyDetails::kInitialIndex));
   return result;
 }
 
 
 void DescriptorArray::SetEnumCache(FixedArray* bridge_storage,
-                                   FixedArray* new_cache) {
+                                   FixedArray* new_cache,
+                                   Object* new_index_cache) {
   ASSERT(bridge_storage->length() >= kEnumCacheBridgeLength);
+  ASSERT(new_index_cache->IsSmi() || new_index_cache->IsFixedArray());
   if (HasEnumCache()) {
     FixedArray::cast(get(kEnumerationIndexIndex))->
       set(kEnumCacheBridgeCacheIndex, new_cache);
+    FixedArray::cast(get(kEnumerationIndexIndex))->
+      set(kEnumCacheBridgeIndicesCacheIndex, new_index_cache);
   } else {
     if (IsEmpty()) return;  // Do nothing for empty descriptor array.
     FixedArray::cast(bridge_storage)->
       set(kEnumCacheBridgeCacheIndex, new_cache);
+    FixedArray::cast(bridge_storage)->
+      set(kEnumCacheBridgeIndicesCacheIndex, new_index_cache);
     NoWriteBarrierSet(FixedArray::cast(bridge_storage),
                       kEnumCacheBridgeEnumIndex,
                       get(kEnumerationIndexIndex));
     set(kEnumerationIndexIndex, bridge_storage);
   }
 }
 
 
 static bool InsertionPointFound(String* key1, String* key2) {
   return key1->Hash() > key2->Hash() || key1 == key2;
@@ skipping 7347 matching lines @@
   if (break_point_objects()->IsUndefined()) return 0;
   // Single break point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 
 } }  // namespace v8::internal