negative = true
		op = op[1:]
	}
	if len(op) == 0 || op[0].ScanToken != scanner.Int {
		p.errorf("TEXT %s: frame size must be an immediate constant", name)
		return
	}
	frameSize := p.positiveAtoi(op[0].String())
	if negative {
		frameSize = -frameSize
	}
	op = op[1:]
	argSize := int64(abi.ArgsSizeUnknown)
	if len(op) > 0 {

			p.errorf("missing closing paren")
		}
		return v
	}
	p.errorf("unexpected %s evaluating expression", tok)
	return 0
}

// positiveAtoi returns an int64 that must be >= 0.
func (p *Parser) positiveAtoi(str string) int64 {
	value, err := strconv.ParseInt(str, 0, 64)
	if err != nil {
		p.errorf("%s", err)
	}
	if value < 0 {
		p.errorf("%s overflows int64", str)
	}