anchor.diff:    defaultValue = unpack(0);
   endinstance
   instance DefaultMask#(RoutingRespT);
  -  defaultMask= unpack(maxBound);
  +  defaultMask = unpack(maxBound);
   endinstance
   
   instance FShow#(RoutingRespT);
  
positive.code:   endrule
  
    function ParserState compute_next_state(Bit#(16) v);
      ParserState nextState = StateStart;
      case (byteSwap(v)) matches
        'h800: begin
          nextState = StateParseIpv4;
        end
        default: begin
          nextState = StateStart;
        end
      endcase
      return nextState;
  
negative.code:     $display(fshow(hdr));
      parseStateFifo.enq(StateParseIpv4);
      parsed_ipv4_protocol_fifo.enq(hdr.protocol);
      next_state_wire[0] <= tagged Valid StateParseStart;
    endaction
    endseq;
    FSM fsm_parse_ipv4 <- mkFSM(stmt_parse_ipv4);
  