include_coverage() scope question.

[mszabo]

So in my test I have a whole bunch of registers and would like to selectively enable coverage on some of the registers. This seems like it should be an easy task, I just replace my

uvm_reg::include_coverage("*",...)

with

uvm_reg::include_coverage("*reg_R*",...)

Now all registers containing the name reg_R will have coverage enabled right? However it doesn't appear to work that way. Digging in to both the register example I see:

Example Register Model New Function (from register/coverage/regmodel..sv) :

function new(string name = "reg_R");
      super.new(name, 8, build_coverage(UVM_CVR_REG_BITS +
                                        UVM_CVR_FIELD_VALS));
      if (has_coverage(UVM_CVR_REG_BITS))
         cg_bits = new();
      if (has_coverage(UVM_CVR_FIELD_VALS))
         cg_vals = new();
   endfunction: new

The call to super.new() takes an argument has_coverage which will make the decision whether or not to build coverage. So this calls build_coverage() which checks the name (using get_full_name()) against a scope database and determines if coverage should be included. However at this point super.new() has not been called so the name will not include in the above case "reg_R".

I suppose the user could call add_coverage() later on after the register model is built, but in the example the only place the cover structures are new'ed is in the new() function. So just changing the has_coverage() won't help at that point.

Am I missing something obvious here or is there no good way of enabling coverage on a specific register without manually editing the register model source.

[mszabo]

So I fixed the problem locally by changing my register model, adding the line add_coverage(build_coverage(UVM_CVR_REG_BITS + UVM_CVR_FIELD_VALS)) immediately following the call to super.new(). Easily fixed but still troublesome as I'm using automatic code generation for the register models, so now I have to convince a 3rd party to update their tool.

[janick]

A bug indeed. Filed as Mantis 3713 (http://www.eda.org/svdb/view.php?id=3713)