RE: [sv-ec] Query on cross

Swapnajit,
The total cross-coverage bins will be 12 as you state, the
guard conditions on bins in the coverpoint do not change the
coverage space as it is stated.

On the second question, you are correct, the cross bins are
not updated if the corresponding bins in the coverpoint do 
not get updated. This is the case if the guard condition for
the coverpoint bin is false or value is ignored.
- Mehdi 

-----Original Message-----
From: owner-sv-ec@eda.org [mailto:owner-sv-ec@eda.org] On Behalf Of
Swapnajit Chakraborti
Sent: Thursday, May 05, 2005 5:55 AM
To: sv-ec@eda.org
Subject: [sv-ec] Query on cross

In the following covergroup example:

...
A: coverpoint a { bins b1[] = {0,1, 2, 3} iff x+y; }
B: coverpoint b { bins b2[] = {0,1, 2} iff x; }
cross A, B;
...

Will the values (true/false) of guard expressions for bins
impact the cross-coverage space? Basically, if there is no
guard expressions in the above example, total cross-coverage bins will
be 12.
Even with guard expressions, shouldn't we calculate total
cross-bins as 12, irrespective of the values of guard expressions?
 
Another related question is regarding the creation of cross-bins.
In the preceeding example, if the values for A & B are 0 and 0
respectively but both "x+y" and "x" are false, should we increment
the corresponding crossbin i.e. <b1[0], b2[0]>? I believe we should
not increment in this case. Similarly, if 0 is declared as an
ignore_bin,
we shouldn't increment <b1[0], b2[0]>.

Swapnajit.