val flags = buf.readShort().toInt() and 0xffff
    require(flags shr 15 != 0) { "not a response" }

    val responseCode = flags and 0xf

    if (responseCode == NXDOMAIN) {
      throw UnknownHostException("$hostname: NXDOMAIN")
    } else if (responseCode == SERVFAIL) {
      throw UnknownHostException("$hostname: SERVFAIL")
    }

    val questionCount = buf.readShort().toInt() and 0xffff

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

	// match: (ANDconst [c] y:(MOVHZreg _))
	// cond: c&0xFFFF == 0xFFFF
	// result: y
	for {
		c := auxIntToInt64(v.AuxInt)
		y := v_0
		if y.Op != OpPPC64MOVHZreg || !(c&0xFFFF == 0xFFFF) {
			break
		}
		v.copyOf(y)
		return true
	}
	// match: (ANDconst [0xFFFF] (MOVHreg x))
	// result: (MOVHZreg x)
	for {
		if auxIntToInt64(v.AuxInt) != 0xFFFF || v_0.Op != OpPPC64MOVHreg {
			break
		}

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

	IN_ACCESS                        = 0x1
	IN_ALL_EVENTS                    = 0xfff
	IN_ATTRIB                        = 0x4
	IN_CLASSA_HOST                   = 0xffffff
	IN_CLASSA_MAX                    = 0x80
	IN_CLASSA_NET                    = 0xff000000
	IN_CLASSA_NSHIFT                 = 0x18
	IN_CLASSB_HOST                   = 0xffff
	IN_CLASSB_MAX                    = 0x10000
	IN_CLASSB_NET                    = 0xffff0000

big_loop:
	MOVOU	(SI), X0
	MOVOU	(DI), X1
	PCMPEQB X0, X1
	PMOVMSKB X1, AX
	XORQ	$0xffff, AX
	JNE	diff16

	MOVOU	16(SI), X0
	MOVOU	16(DI), X1
	PCMPEQB X0, X1
	PMOVMSKB X1, AX
	XORQ	$0xffff, AX
	JNE	diff32

	MOVOU	32(SI), X0
	MOVOU	32(DI), X1
	PCMPEQB X0, X1
	PMOVMSKB X1, AX
	XORQ	$0xffff, AX
	JNE	diff48

	MOVOU	48(SI), X0
	MOVOU	48(DI), X1
	PCMPEQB X0, X1

	// match: (MOVWLSX (ANDLconst [c] x))
	// cond: c & 0x8000 == 0
	// result: (ANDLconst [c & 0x7fff] x)
	for {
		if v_0.Op != Op386ANDLconst {
			break
		}
		c := auxIntToInt32(v_0.AuxInt)
		x := v_0.Args[0]
		if !(c&0x8000 == 0) {
			break
		}
		v.reset(Op386ANDLconst)
		v.AuxInt = int32ToAuxInt(c & 0x7fff)
		v.AddArg(x)
		return true
	}
	return false
}