Optimize the equality check case of ICCompare stubs.

src/heap.cc

 // Copyright 2011 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 2350 matching lines @@
   }
   set_prototype_accessors(Foreign::cast(obj));
 
   // Allocate the code_stubs dictionary. The initial size is set to avoid
   // expanding the dictionary during bootstrapping.
   { MaybeObject* maybe_obj = NumberDictionary::Allocate(128);
     if (!maybe_obj->ToObject(&obj)) return false;
   }
   set_code_stubs(NumberDictionary::cast(obj));
 
+
+  // Allocate the known objects compare stub  dictionary.
+  { MaybeObject* maybe_obj = NumberDictionary::Allocate(4);
+    if (!maybe_obj->ToObject(&obj)) return false;
+  }
+  set_compare_stubs_known_objects(NumberDictionary::cast(obj));
+
+
   // Allocate the non_monomorphic_cache used in stub-cache.cc. The initial size
   // is set to avoid expanding the dictionary during bootstrapping.
   { MaybeObject* maybe_obj = NumberDictionary::Allocate(64);
     if (!maybe_obj->ToObject(&obj)) return false;
   }
   set_non_monomorphic_cache(NumberDictionary::cast(obj));
 
   { MaybeObject* maybe_obj = AllocatePolymorphicCodeCache();
     if (!maybe_obj->ToObject(&obj)) return false;
   }
@@ skipping 4074 matching lines @@
   isolate_->heap()->store_buffer()->Compact();
   isolate_->heap()->store_buffer()->Filter(MemoryChunk::ABOUT_TO_BE_FREED);
   for (chunk = chunks_queued_for_free_; chunk != NULL; chunk = next) {
     next = chunk->next_chunk();
     isolate_->memory_allocator()->Free(chunk);
   }
   chunks_queued_for_free_ = NULL;
 }
 
 } }  // namespace v8::internal