// If parsing fails or an integer overflow occurs, err will be set.
func (p *parser) parseNumeric(b []byte) int64 {
	// Check for base-256 (binary) format first.
	// If the first bit is set, then all following bits constitute a two's
	// complement encoded number in big-endian byte order.
	if len(b) > 0 && b[0]&0x80 != 0 {
		// Handling negative numbers relies on the following identity:
		//	-a-1 == ^a
		//

	var ok, diag bool
	var failedFile string
	for _, f := range flag.Args() {
		lexer := lex.NewLexer(f)
		parser := asm.NewParser(ctxt, architecture, lexer)
		ctxt.DiagFunc = func(format string, args ...interface{}) {
			diag = true
			log.Printf(format, args...)
		}
		if *flags.SymABIs {
			ok = parser.ParseSymABIs(buf)
		} else {
			pList := new(obj.Plist)
			pList.Firstpc, ok = parser.Parse()

	CALL (AX)(PC*1)                 // ERROR "invalid instruction"
	CALL (AX)(SB*1)                 // ERROR "invalid instruction"
	CALL (AX)(FP*1)                 // ERROR "invalid instruction"
	// Forbid memory operands for MOV CR/DR. See #24981.
	MOVQ CR0, (AX)                  // ERROR "invalid instruction"
	MOVQ CR2, (AX)                  // ERROR "invalid instruction"

}

func (l Token) String() string {
	return l.text
}

// A Macro represents the definition of a #defined macro.
type Macro struct {
	name   string   // The #define name.
	args   []string // Formal arguments.
	tokens []Token  // Body of macro.
}

// Tokenize turns a string into a list of Tokens; used to parse the -D flag and in tests.
func Tokenize(str string) []Token {