void LIRGenerator::do_MonitorEnter(MonitorEnter* x) {
  assert(x->is_pinned(),"");
  LIRItem obj(x->obj(), this);
  obj.load_item();

  set_no_result(x);

  // "lock" stores the address of the monitor stack slot, so this is not an oop
  LIR_Opr lock = new_register(T_INT);
  // Need a scratch register for biased locking on x86
  LIR_Opr scratch = LIR_OprFact::illegalOpr;
  if (UseBiasedLocking) {
    scratch = new_register(T_INT);
  }

  CodeEmitInfo* info_for_exception = NULL;
  if (x->needs_null_check()) {
    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(), scratch,
                        x->monitor_no(), info_for_exception, info);
}
Unknown