StringDictionary::FindEntry optimized for symbol strings.

src/objects.h

 // Copyright 2006-2009 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 1994 matching lines @@
 
   // Constant used for denoting a absent entry.
   static const int kNotFound = -1;
 
   // Maximal capacity of HashTable. Based on maximal length of underlying
   // FixedArray. Staying below kMaxCapacity also ensures that EntryToIndex
   // cannot overflow.
   static const int kMaxCapacity =
       (FixedArray::kMaxLength - kElementsStartOffset) / kEntrySize;
 
-  // Find entry for key otherwise return -1.
+  // Find entry for key otherwise return kNotFound.
   int FindEntry(Key key);
 
  protected:
 
   // Find the entry at which to insert element with the given key that
   // has the given hash value.
   uint32_t FindInsertionEntry(uint32_t hash);
 
   // Returns the index for an entry (of the key)
   static inline int EntryToIndex(int entry) {
@@ skipping 261 matching lines @@
     ASSERT(obj->IsDictionary());
     return reinterpret_cast<StringDictionary*>(obj);
   }
 
   // Copies enumerable keys to preallocated fixed array.
   void CopyEnumKeysTo(FixedArray* storage, FixedArray* sort_array);
 
   // For transforming properties of a JSObject.
   Object* TransformPropertiesToFastFor(JSObject* obj,
                                        int unused_property_fields);
+
+  // Find entry for key otherwise return kNotFound. Optimzed version of
+  // HashTable::FindEntry.
+  int FindEntry(String* key);
 };
 
 
 class NumberDictionaryShape {
  public:
   static inline bool IsMatch(uint32_t key, Object* other);
   static inline uint32_t Hash(uint32_t key);
   static inline uint32_t HashForObject(uint32_t key, Object* object);
   static inline Object* AsObject(uint32_t key);
   static const int kPrefixSize = 2;
@@ skipping 3053 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_