A set of values or transitions associated with a coverage point can be explicitly excluded from coverage by specifying them as ignore_bins. Ignore bin syntax can be used for dynamic coverage bin disabling and can be used for modelling coverage shape syntax of VERA.

  1 module test();
  2 
  3 logic [2:0] addr;
  4 reg ce;
  5 
  6 covergroup address_cov () @ (posedge ce);
  7   ADDRESS : coverpoint addr {
  8     ignore_bins ignore_tran = (0=>2=>1);
  9     ignore_bins ignore_vals = {0,1,2,3};
 10   }
 11 endgroup
 12 
 13 address_cov my_cov = new();
 14 
 15 initial begin
 16   ce   <= 0;
 17   $monitor("ce %b addr 8'h%x",ce,addr);
 18   repeat (10) begin
 19     ce <= 1;
 20     addr <= $urandom_range(0,7);
 21      #10 ;
 22     ce <= 0;
 23      #10 ;
 24   end
 25 end
 26 
 27 endmodule

 ce 1 addr 8'h6
 ce 0 addr 8'h6
 ce 1 addr 8'h4
 ce 0 addr 8'h4
 ce 1 addr 8'h5
 ce 0 addr 8'h5
 ce 1 addr 8'h2
 ce 0 addr 8'h2
 ce 1 addr 8'h3
 ce 0 addr 8'h3
 ce 1 addr 8'h7
 ce 0 addr 8'h7
 ce 1 addr 8'h0
 ce 0 addr 8'h0
 ce 1 addr 8'h7
 ce 0 addr 8'h7
 ce 1 addr 8'h6
 ce 0 addr 8'h6
 ce 1 addr 8'h3
 ce 0 addr 8'h3

 ===========================================================
 Group : test::address_cov
 ===========================================================
 SCORE  WEIGHT GOAL   
 100.00 1      100    
 -----------------------------------------------------------
 Summary for Group   test::address_cov
 
 CATEGORY  EXPECTED UNCOVERED COVERED PERCENT 
 Variables 4        -3        7       100.00  
 
 Variables for Group  test::address_cov
 
 VARIABLE EXPECTED UNCOVERED COVERED PERCENT GOAL WEIGHT 
 ADDRESS  4        -3        7       100.00  100  1      
 -----------------------------------------------------------
 Summary for Variable ADDRESS
 
 CATEGORY                     EXPECTED UNCOVERED COVERED PERCENT 
 Automatically Generated Bins 4        -3        7       100.00  
 
 Automatically Generated Bins for ADDRESS
 
 Excluded/Illegal bins
 
 NAME                COUNT                   
 ignore_tran         0     Excluded 
 ignore_vals         0     Excluded 
 [auto[0] - auto[3]] --    Excluded (4 bins) 
 
 Covered bins
 
 NAME    COUNT AT LEAST  
 auto[0] 1     1        
 auto[2] 1     1        
 auto[3] 2     1        
 auto[4] 1     1        
 auto[5] 1     1        
 auto[6] 2     1        
 auto[7] 2     1        

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