XTAH	R0<<16, R5, R2     // ERROR "illegal shift"
	XTABU	R0->24, R5, R2     // ERROR "illegal shift"
	XTAHU	R0@>1, R5, R2      // ERROR "illegal shift"
	AND.W	R0, R1             // ERROR "invalid .W suffix"
	ORR.P	R2, R3, R4         // ERROR "invalid .P suffix"
	CMP.S	R1, R2	           // ERROR "invalid .S suffix"
	BIC.P	$124, R1, R2       // ERROR "invalid .P suffix"
	MOVW.S	$124, R1           // ERROR "invalid .S suffix"

	case lex.LSH:
		op = 0
	case lex.RSH:
		op = 1
	case lex.ARR:
		op = 2
	case lex.ROT:
		// following instructions on ARM64 support rotate right
		// AND, ANDS, TST, BIC, BICS, EON, EOR, ORR, MVN, ORN
		op = 3
	}
	tok := p.next()
	str := tok.String()
	var count int16
	switch tok.ScanToken {
	case scanner.Ident:
		if p.arch.Family == sys.ARM64 {