s := NewScanner(buf)
		s.Split(ScanRunes)
		var i, runeCount int
		var expect rune
		// Use a string range loop to validate the sequence of runes.
		for i, expect = range test {
			if !s.Scan() {
				break
			}
			runeCount++
			got, _ := utf8.DecodeRune(s.Bytes())
			if got != expect {
				t.Errorf("#%d: %d: expected %q got %q", n, i, expect, got)
			}
		}
		if s.Scan() {

	p.expect(expected, expected.String())
	return p.next()
}

// expectOperandEnd verifies that the parsing state is properly at the end of an operand.
func (p *Parser) expectOperandEnd() {
	p.expect(scanner.EOF, "end of operand")
}

// expect verifies that the next item has the expected type. It does not consume it.

func (p *Parser) asmData(operands [][]lex.Token) {
	if len(operands) != 2 {
		p.errorf("expect two operands for DATA")
		return
	}

	// Operand 0 has the general form foo<>+0x04(SB)/4.
	op := operands[0]
	n := len(op)
	if n < 3 || op[n-2].ScanToken != '/' || op[n-1].ScanToken != scanner.Int {
		p.errorf("expect /size for DATA argument")
		return
	}
	szop := op[n-1].String()
	sz, err := strconv.Atoi(szop)

// ARM64RegisterArrangement constructs an ARM64 vector register arrangement.
func ARM64RegisterArrangement(reg int16, name, arng string) (int64, error) {
	var curQ, curSize uint16
	if name[0] != 'V' {
		return 0, errors.New("expect V0 through V31; found: " + name)
	}
	if reg < 0 {
		return 0, errors.New("invalid register number: " + name)
	}
	switch arng {
	case "B8":
		curSize = 0
		curQ = 0
	case "B16":
		curSize = 0

		deviceCwd = path.Join(deviceGoroot, "src", importPath)
	} else {
		deviceCwd = path.Join(deviceGopath, "src", importPath)
		if modDir != "" {
			// In module mode, the user may reasonably expect the entire module
			// to be present. Copy it over.
			deviceModDir := path.Join(deviceGopath, "src", modPath)
			if err := adb("exec-out", "mkdir", "-p", path.Dir(deviceModDir)); err != nil {
				return 0, err
			}