--- old/src/hotspot/share/opto/chaitin.cpp	2018-12-18 11:42:48.600897676 +0100
+++ new/src/hotspot/share/opto/chaitin.cpp	2018-12-18 11:42:48.309043681 +0100
@@ -2229,6 +2229,9 @@
           _matcher._parm_regs[j].second() == reg ) {
         tty->print("parm %d: ",j);
         domain->field_at(j + TypeFunc::Parms)->dump();
+        if (j == C->get_res_entry()._offset) {
+          tty->print(" [RESERVED] ");
+        }
         tty->cr();
         break;
       }