Label isNull = e.make_label();
Label skip = e.make_label();
    private static void hash_object(CodeEmitter e, Type type, Customizer customizer) {        // (f == null) ? 0 : f.hashCode();        Label isNull = e.make_label();        Label end = e.make_label();        e.dup();        e.ifnull(isNull);        if (customizer != null) {            customizer.customize(e, type);        }        e.invoke_virtual(Constants.TYPE_OBJECT, HASH_CODE);        e.goTo(end);        e.mark(isNull);        e.pop();        e.push(0);        e.mark(end);    }