if (debug) { System.out.println("didn't find it, returning false"); } return  false; }
  public boolean contains(OPT_Register item) {    if (debug) {      System.out.println("looking for " + item + " in " + this);    }    // simply linear search    OPT_LiveSetEnumerator enum = enumerator();    while (enum.hasMoreElements()) {      OPT_Register elem = ((OPT_RegisterOperand)enum.nextElement()).register;      if (item == elem) {        if (debug) {          System.out.println("found it, returning true");        }        return  true;      }    }