Reporting ignored bins

[Roger Smith]

I’m using CoveragePkg.vhd,

I have some bins which I’m using to drive the simulation, using GenBin and setting an ‘AtLeast’ value. This works OK.

I have some illegal bins, using IllegalBin (‘AtLeast’ value is zero) This works OK.

I want to have some bins which do not drive the simulation, but which I’d like to know if they’ve been hit or not. I have 2 options:

• If I use GenBin with AtLeast set to zero, an AtLeast value of 1 is enforced (so if the bin isn’t hit then I can’t check IsCovered).
• If I use IgnoreBin then when I WriteBin they are not reported so I can’t see if the bins have been hit or not.

Is it possible to have bins which do not affect IsCovered if they have zero count, but do get reported so I can see whether they have a count or not?

[Jim Lewis]

Hi Roger,

Ignore bins always have a count of 0.   So even if they were reported, it would not do what you want.

You could do two separate coverage bins: one to generate stimulus and one to collect results.   If you use a procedure to set the bins, the common parts would only need to be generated once.  

I added a note to look at coverage bins with a coverage goal of 0 for a future revision.

Best Regards,

Jim 

[Roger Smith]

Thanks Jim.

Regards,

Roger*

[Roger Smith]

Hi,

Can I access the values in the bins?

The bin counts (including anything in illegal bins) get reported to the ModelSim Transcript window (using WriteBin).

Is it possible for my VHDL (or TCL) to access the values?

[Jim Lewis]

Hi Roger,
I just did a code review regarding AtLeast.  Looking at the code, the AtLeast value is the maximum of the one specified by AddBins (the way I usually show to enter it) and the value specified by GenBin (also specified by a first integer value – but then also requires at least 4 parameters be used).   Hence, if you specify both, you may be able to get a value of 0 into the model as it is.

For getting at bin values, see GetBin.

Best Regards,
Jim

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