Observing duplicate bins within covergroup instance

SystemVerilog
,
1

Hello Forum,
I have the following code ::

 class tc_atc_req extends uvm_sequence_item;
  bit [15:0] nsid;
  bit [11:0] hfid;
 ....
endclass

// Within coverage component class 'nvmetc_cov'
covergroup axis_tc_atc_rsrv_if with function sample(tc_atc_req tr);
  
  axis_tc_atc_rsrv_if_hfid: coverpoint tr.hfid[10:0]{  
                                                       bins hfid0[]    	    = { 0 , [32:1055] } iff( tr.hfid[11] == 1'h0 );   
                                                       ignore_bins hfid0_ill = {[1:31],[1056:$]} iff( tr.hfid[11] == 1'h0 );   
                                                        
                                                       // Dual Host Mode
                                                       bins hfid1[]    	     = { 0 , [32:543] }  iff( tr.hfid[11] == 1'h1 ) ;  
                                                       ignore_bins hfid1_ill  = {[1:31],[544:$]}  iff( tr.hfid[11] == 1'h1 );   
                                                     }
  axis_tc_atc_rsrv_if_nsid: coverpoint tr.nsid[14:0]{   bins nsid[]     = {[0:1023]};         
                                                        ignore_bins nsid_ill = {[1024:$]}; }   
 
  endgroup
  
    // Within constructor
    axis_tc_atc_rsrv_if = new();

Note that there is a single instance of the covergroup 'axis_tc_atc_rsrv_if ’

However, in the html coverage report I observe ::

CG nvmetc_env_pkg::nvmetc_cov::axis_tc_atc_rsrv_if
 Cg VLOG.LIB.nvmetc_env_pkg::nvmetc_cov::axis_tc_atc_rsrv_if::SHAPE{Guard_ON(axis_tc_atc_rsrv_if_hfid.hfid1_ill),Guard_OFF(axis_tc_atc_rsrv_if_hfid.hfid0_ill)}
    Cp axis_tc_atc_rsrv_if_nsid
    Cp axis_tc_atc_rsrv_if_hfid
 Cg VLOG.LIB.nvmetc_env_pkg::nvmetc_cov::axis_tc_atc_rsrv_if::SHAPE{Guard_ON(axis_tc_atc_rsrv_if_hfid.hfid0_ill),Guard_OFF(axis_tc_atc_rsrv_if_hfid.hfid1_ill)}
    Cp axis_tc_atc_rsrv_if_nsid
    Cp axis_tc_atc_rsrv_if_hfid

The coverpoints ‘axis_tc_atc_rsrv_if_hfid’ & ‘axis_tc_atc_rsrv_if_nsid’ appear twice in the coverage report with a different coverage report of covered & uncovered bins

(1) Why is that I observe the same coverpoint label twice ?
(2) What is the meaning of Guard_ON and Guard_OFF ? The iff clause applies to a coverpoint and not a covergroup

Thanks in Advance

2

Unfortunately we do not see all your code, But the html-report shows your coverpoints for
hfid1_ill and
hfid0_ill
These are different interfaces.

3

Unfortunately, I can’t share the entire code ( as it’s from a project I am working on ) but the above covergroup is a snippet of the actual code.
Although the covergroup has a single instance in the coverage component, I observe the Guard_ON and Guard_OFF which has me confused.
It seems to use the iff clause associated with coverpoint ‘axis_tc_atc_rsrv_if_hfid’

4

It’s likely that this is tool-specific terminology. This Siemens-sponsored public forum is not intended for discussing tool-specific issues. Please refer to your tool’s User Manual or contact your tool vendor for support.