Coverpoint using concantenation of integer values)

Coverage
,
1

I’m trying to have a coverpoint that will cover the resultant of a function that will return integer values.

Like:

function int diff_seq_addr(address_t a, address_t b);
  case (a-b) inside
    0        : return 0;
    [-31:31] : return 2;
    default  : return 1;
  endcase
endfunction : diff_seq_addr

  seq_addr_cp : coverpoint {diff_seq_addr(a, b),diff_seq_addr(a,c),diff_seq_addr(a,d),diff_seq_addr(a,e)} iff valid {
    wildcard bins AA             = {0???};
    wildcard bins ABA            = {10??};
    wildcard bins ABCA           = {110?};
    bins ABCDA          = {1110};
    wildcard bins AAA            = {000?};
    bins AAAA           = {0000};
    bins other = default;
  }

But compilation is throwing error in the wildcard bins line. I get what the problem is: The problem here is that I’m concantenating integer values, but not using them the right way in the bins expression. Can you please help me resolve this?

Thanks

2

In reply to Ramyas:
It always helps to show the error. I assume it is a syntax error because you are not writing the numeric literal correctly. It needs a width and base qualifier like 4’b0??? instead of just 0???.

As you have written your concatenation, it would be 128-bit result. Did you mean to write

seq_addr_cp : coverpoint {diff_seq_addr(a,b) == 1,
                          diff_seq_addr(a,c) == 1,
                          diff_seq_addr(a,d) == 1,
                          diff_seq_addr(a,e) == 1} iff valid {

That would be a 4-bit result.

Or should your function return a 2-bit result instead of an int?