*** old/src/share/vm/runtime/stackValue.cpp	Wed Jul 22 12:17:29 2009
--- new/src/share/vm/runtime/stackValue.cpp	Wed Jul 22 12:17:29 2009

*** 102,112 ****
--- 102,122 ----
        Handle h(oopDesc::decode_heap_oop(value.noop));
        return new StackValue(h);
      }
  #endif
      case Location::oop: {
        Handle h(*(oop *)value_addr); // Wrap a handle around the oop
+       oop val = *(oop *)value_addr;
+ #ifdef _LP64
+       if (Universe::narrow_oop_base() == (address)(void*)val) {
+          // Compiled code may produce decoded oop = narrow_oop_base
+          // when a narrow oop implicit null check is used.
+          // The narrow_oop_base could be NULL or be the address
+          // of the page below heap. Use NULL value for both cases.
+          val = (oop)NULL;
+       }
+ #endif
+       Handle h(val); // Wrap a handle around the oop
        return new StackValue(h);
      }
      case Location::addr: {
        ShouldNotReachHere(); // both C1 and C2 now inline jsrs
      }