*** old/src/share/vm/opto/compile.cpp	Fri Jun 13 09:30:23 2014
--- new/src/share/vm/opto/compile.cpp	Fri Jun 13 09:30:22 2014

*** 3785,3794 ****
--- 3785,3844 ----
      *constant_addr = cb.consts()->target(*labels.at(i), (address) constant_addr);
      cb.consts()->relocate((address) constant_addr, relocInfo::internal_word_type);
    }
  }
  
+ //----------------------------static_subtype_check-----------------------------
+ // Shortcut important common cases when superklass is exact:
+ // (0) superklass is java.lang.Object (can occur in reflective code)
+ // (1) subklass is already limited to a subtype of superklass => always ok
+ // (2) subklass does not overlap with superklass => always fail
+ // (3) superklass has NO subtypes and we can check with a simple compare.
+ int Compile::static_subtype_check(ciKlass* superk, ciKlass* subk) {
+   if (StressReflectiveCode) {
+     return SSC_full_test;       // Let caller generate the general case.
+   }
+ 
+   if (superk == env()->Object_klass()) {
+     return SSC_always_true;     // (0) this test cannot fail
+   }
+ 
+   ciType* superelem = superk;
+   if (superelem->is_array_klass())
+     superelem = superelem->as_array_klass()->base_element_type();
+ 
+   if (!subk->is_interface()) {  // cannot trust static interface types yet
+     if (subk->is_subtype_of(superk)) {
+       return SSC_always_true;   // (1) false path dead; no dynamic test needed
+     }
+     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
+         !superk->is_subtype_of(subk)) {
+       return SSC_always_false;
+     }
+   }
+ 
+   // If casting to an instance klass, it must have no subtypes
+   if (superk->is_interface()) {
+     // Cannot trust interfaces yet.
+     // %%% S.B. superk->nof_implementors() == 1
+   } else if (superelem->is_instance_klass()) {
+     ciInstanceKlass* ik = superelem->as_instance_klass();
+     if (!ik->has_subklass() && !ik->is_interface()) {
+       if (!ik->is_final()) {
+         // Add a dependency if there is a chance of a later subclass.
+         dependencies()->assert_leaf_type(ik);
+       }
+       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
+     }
+   } else {
+     // A primitive array type has no subtypes.
+     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
+   }
+ 
+   return SSC_full_test;
+ }
+ 
  // The message about the current inlining is accumulated in
  // _print_inlining_stream and transfered into the _print_inlining_list
  // once we know whether inlining succeeds or not. For regular
  // inlining, messages are appended to the buffer pointed by
  // _print_inlining_idx in the _print_inlining_list. For late inlining,