--- old/src/share/vm/opto/parse2.cpp	2013-10-17 18:54:53.292930046 +0200
+++ new/src/share/vm/opto/parse2.cpp	2013-10-17 18:54:53.058550438 +0200
@@ -2239,6 +2239,31 @@
     a = pop();
     b = pop();
     c = _gvn.transform( new (C) CmpPNode(b, a) );
+    // If this is transformed by the _gvn to a comparison with the low
+    // level klass then we may be able to use speculation
+    if (c->Opcode() == Op_CmpP &&
+        (c->in(1)->Opcode() == Op_LoadKlass || c->in(1)->Opcode() == Op_DecodeNKlass ) &&
+        c->in(2)->is_Con()) {
+      Node* load_klass = NULL;
+      if (c->in(1)->Opcode() == Op_DecodeNKlass) {
+        load_klass = c->in(1)->in(1);
+      } else {
+        load_klass = c->in(1);
+      }
+      if (load_klass->in(2)->is_AddP()) {
+        Node* obj = load_klass->in(2)->in(AddPNode::Address);
+        const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
+        if (obj_type->speculative_type() != NULL) {
+          ciKlass* k = obj_type->speculative_type();
+          inc_sp(2);
+          obj = maybe_cast_profiled_obj(obj, k);
+          dec_sp(2);
+          // now redo the CmpP which should always fail or succeed and
+          // be optimized out
+          c = _gvn.transform( new (C) CmpPNode(b, a) );
+        }
+      }
+    }
     do_if(btest, c);
     break;