Better support for 'polymorphic' JS and external arrays

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 ee8c0c79b67a56c4383e82f3e29bf32b888bad36..c305572ca9a64ef2ad0e044181b43ca3d76259a9 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -201,14 +201,22 @@ class MacroAssembler: public Assembler {
   // Compare instance type for map.
   void CmpInstanceType(Register map, InstanceType type);
 
-  // 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)
+  // 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)
   void CheckMap(Register obj,
                 Handle<Map> map,
                 Label* fail,
                 bool is_heap_object);
 
+  // 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
+  // known to be a heap object)
+  void DispatchMap(Register obj,
+                   Handle<Map> map,
+                   Handle<Code> success,
+                   bool is_heap_object);
+
   // Check if the object in register heap_object is a string. Afterwards the
   // register map contains the object map and the register instance_type
   // contains the instance_type. The registers map and instance_type can be the