Better support for 'polymorphic' JS and external arrays

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index 8e8409d6914dee698cc73af5fdda26a83f1f0de6..b24ca541f29efedd139608a20b11632c04b8e48b 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -577,6 +577,7 @@ class MacroAssembler: public Assembler {
                 Label* fail,
                 bool is_heap_object);
 
+
   void CheckMap(Register obj,
                 Register scratch,
                 Heap::RootListIndex index,
@@ -584,6 +585,16 @@ class MacroAssembler: public Assembler {
                 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,
+                   Register scratch,
+                   Handle<Map> map,
+                   Handle<Code> success,
+                   bool is_heap_object);
+
+
   // Compare the object in a register to a value from the root list.
   // Uses the ip register as scratch.
   void CompareRoot(Register obj, Heap::RootListIndex index);