// SmallVector<Values, 4> new_values;
// for (int i = 0; i < num_iterations; ++i) {
//   body_fn(old_values, &new_values, ...);
//   old_values = new_values;
// }
// ```
//
// Under the hood an induction variable is prepended to values to control the
// number of iterations, but that is transparent to `body_fn`, which does not
// need to care about that.
static void CreateWhile32(Location loc, int num_iterations,

  auto cond_fn =
      symbol_table.lookupNearestSymbolFrom<func::FuncOp>(*this, getCondAttr());
  auto body_fn =
      symbol_table.lookupNearestSymbolFrom<func::FuncOp>(*this, getBodyAttr());
  if (!cond_fn) {
    return emitOpError("cond refers to an undefined function : ") << getCond();
  }
  if (!body_fn) {
    return emitOpError("body refers to an undefined function : ") << getBody();
  }

	var extOff, bodyOff int
	if typ == syscall.NET_RT_IFLISTL {
		if len(b) < 20 {
			return nil, errMessageTooShort
		}
		extOff = int(nativeEndian.Uint16(b[18:20]))
		bodyOff = int(nativeEndian.Uint16(b[16:18]))
	} else {
		extOff = w.extOff
		bodyOff = w.bodyOff
	}
	if len(b) < extOff || len(b) < bodyOff {
		return nil, errInvalidMessage
	}

func probeRoutingStack() (int, map[int]*wireFormat) {
	var p uintptr
	rtm := &wireFormat{extOff: 40, bodyOff: sizeofRtMsghdrDragonFlyBSD4}
	rtm.parse = rtm.parseRouteMessage
	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrDragonFlyBSD4}
	ifm.parse = ifm.parseInterfaceMessage
	ifam := &wireFormat{extOff: sizeofIfaMsghdrDragonFlyBSD4, bodyOff: sizeofIfaMsghdrDragonFlyBSD4}
	ifam.parse = ifam.parseInterfaceAddrMessage

		if compatFreeBSD32 {
			ifm.bodyOff = sizeofIfMsghdrFreeBSD7Emu
		} else {
			ifm.bodyOff = sizeofIfMsghdrFreeBSD7
		}
	case 800000 <= rel && rel < 900000:
		if compatFreeBSD32 {
			ifm.bodyOff = sizeofIfMsghdrFreeBSD8Emu
		} else {
			ifm.bodyOff = sizeofIfMsghdrFreeBSD8
		}
	case 900000 <= rel && rel < 1000000:
		if compatFreeBSD32 {
			ifm.bodyOff = sizeofIfMsghdrFreeBSD9Emu
		} else {

	rtm := &wireFormat{extOff: 36, bodyOff: sizeofRtMsghdrDarwin15}
	rtm.parse = rtm.parseRouteMessage
	rtm2 := &wireFormat{extOff: 36, bodyOff: sizeofRtMsghdr2Darwin15}
	rtm2.parse = rtm2.parseRouteMessage
	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrDarwin15}
	ifm.parse = ifm.parseInterfaceMessage
	ifm2 := &wireFormat{extOff: 32, bodyOff: sizeofIfMsghdr2Darwin15}
	ifm2.parse = ifm2.parseInterfaceMessage

	rtm := &wireFormat{extOff: 40, bodyOff: sizeofRtMsghdrNetBSD7}
	rtm.parse = rtm.parseRouteMessage
	ifm := &wireFormat{extOff: 16, bodyOff: sizeofIfMsghdrNetBSD7}
	ifm.parse = ifm.parseInterfaceMessage
	ifam := &wireFormat{extOff: sizeofIfaMsghdrNetBSD7, bodyOff: sizeofIfaMsghdrNetBSD7}
	ifam.parse = ifam.parseInterfaceAddrMessage
	ifanm := &wireFormat{extOff: sizeofIfAnnouncemsghdrNetBSD7, bodyOff: sizeofIfAnnouncemsghdrNetBSD7}

	nativeEndian.PutUint32(b[20:24], uint32(m.Seq))
	attrs, err := marshalAddrs(b[w.bodyOff:], m.Addrs)
	if err != nil {
		return nil, err
	}
	if attrs > 0 {
		nativeEndian.PutUint32(b[12:16], uint32(attrs))
	}
	return b, nil
}

func (w *wireFormat) parseRouteMessage(typ RIBType, b []byte) (Message, error) {
	if len(b) < w.bodyOff {
		return nil, errMessageTooShort
	}
	l := int(nativeEndian.Uint16(b[:2]))

		extOff:  w.extOff,
		raw:     b[:l],
	}
	a, err := parseLinkAddr(b[w.bodyOff:])
	if err != nil {
		return nil, err
	}
	m.Addrs[syscall.RTAX_IFP] = a
	m.Name = a.(*LinkAddr).Name
	return m, nil
}

func (w *wireFormat) parseInterfaceAddrMessage(_ RIBType, b []byte) (Message, error) {
	if len(b) < w.bodyOff {
		return nil, errMessageTooShort
	}
	l := int(nativeEndian.Uint16(b[:2]))
	if len(b) < l {

func probeRoutingStack() (int, map[int]*wireFormat) {
	var p uintptr
	rtm := &wireFormat{extOff: -1, bodyOff: -1}
	rtm.parse = rtm.parseRouteMessage
	ifm := &wireFormat{extOff: -1, bodyOff: -1}
	ifm.parse = ifm.parseInterfaceMessage
	ifam := &wireFormat{extOff: -1, bodyOff: -1}
	ifam.parse = ifam.parseInterfaceAddrMessage
	ifanm := &wireFormat{extOff: -1, bodyOff: -1}
	ifanm.parse = ifanm.parseInterfaceAnnounceMessage