44. Bus Error Checker

How do you plan to solve it?

/*Write your code here*/
module error_checker_xz(
    input [7:0] bus,
    output all_known,
    output has_unknown,
    output [7:0] bus_if_known
);

wire x = (^(bus ^ bus)) === 1'bx;
assign bus_if_known = (all_known) ? bus : 8'h00;
assign all_known = ~x;
assign has_unknown = x;
endmodule