def _lenstr(ins):
    ''' Returns string length
    '''
    (tmp1, output) = _str_oper(ins.quad[2], no_exaf=True)
    if tmp1:
        output.append('push hl')

    output.append('call __STRLEN')
    output.extend(_free_sequence(tmp1))
    output.append('push hl')
    REQUIRES.add('strlen.asm')
    return output
Returns string length