Make sure transitioned arrays efficiently call builtin Array functions

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index e6a17417d832e41f65167a178e438ca954b40404..f7400ad390cc50c03b4a7c64b0b105586a39968a 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// 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:
@@ -356,13 +356,24 @@ class MacroAssembler: public Assembler {
                                    Label* fail,
                                    bool specialize_for_processor);
 
+  // Compare an object's map with the specified map and its transitioned
+  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. FLAGS are set with
+  // result of map compare. If multiple map compares are required, the compare
+  // sequences branches to early_success.
+  void CompareMap(Register obj,
+                  Handle<Map> map,
+                  Label* early_success,
+                  CompareMapMode mode = REQUIRE_EXACT_MAP);
+
   // Check if the map of an object is equal to a specified map and branch to
   // label if not. Skip the smi check if not required (object is known to be a
-  // heap object)
+  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
+  // against maps that are ElementsKind transition maps of the specificed map.
   void CheckMap(Register obj,
                 Handle<Map> map,
                 Label* fail,
-                SmiCheckType smi_check_type);
+                SmiCheckType smi_check_type,
+                CompareMapMode mode = REQUIRE_EXACT_MAP);
 
   // Check if the map of an object is equal to a specified map and branch to a
   // specified target if equal. Skip the smi check if not required (object is