def get_add_llil(src):
    """
    Returns llil to add
    :param src: source of operation
    :return: generator for llil expression for add
    """

    def add_llil(il, instr):
        return il.set_reg(4, 'a', il.add(4, il.reg(4, 'a'), src(il, instr)))

    return add_llil