src/hotspot/cpu/x86/c1_LIRGenerator_x86.cpp

@@ -317,11 +317,12 @@
      info_for_exception = state_for(x);
    }
    // this CodeEmitInfo must not have the xhandlers because here the
    // object is already locked (xhandlers expect object to be unlocked)
    CodeEmitInfo* info = state_for(x, x->state(), true);
-   monitor_enter(obj.result(), lock, syncTempOpr(), LIR_OprFact::illegalOpr,
+   LIR_Opr tmp = UseFastLocking ? new_register(T_INT) : LIR_OprFact::illegalOpr;
+   monitor_enter(obj.result(), lock, syncTempOpr(), tmp,
                          x->monitor_no(), info_for_exception, info);
  }
  
  
  void LIRGenerator::do_MonitorExit(MonitorExit* x) {