Cleaning up a layout view

I forgot about the terminals...

(foreach term (setof term cv~>terminals (not (caar term~>pins~>figs))) (dbDeleteObject term))

not sure about the extent boundary though...sorry

Max

Max.

Thank you. Your solution is more reliable than mine. I wonder why Cadence does not clean up these by default.

-Ramakrishnan

Hi Ramakrishnan,

It does clean up by default (certainly VLS XL). One thing to remember however is that deleting nets which don't have any figures means you may be deleting the information that VLS XL uses to know what needs to be connected - there may be logical connections in the database (e.g. connections of the nets to instTerms) but no physical information yet, and if you remove the logical information then VLS XL won't know that a net needs connecting.

Similarly terminals should get removed if the pins are removed - provided that the terminal is not supposed to be in the database (VLS XL also would keep the terminals there if the pin has not been placed yet).

So be very careful about doing this kind of "clean up". Yes, steiners do seem to go a bit awry at times (although this seems to be better nowadays than in the past) which causes the "fit" not to work properly, but be cautious about removing connectivity information.

Oh, and Max's code won't be very efficient for large designs because it's repeatedly building a list of the net names for all shapes as it iterates over each net. You could (I think) achieve the same thing with:

mapcar('dbDeleteObject setof(net cv~>nets !(net~>pins || net~>figs)))

If you wanted to ensure that logically connected nets were also preserved, you could do:

mapcar('dbDeleteObject setof(net cv~>nets !(net~>instTerms || net~>term || net~>figs)))

However, as I said above, I'd be cautious about doing that (it's quite possible that this also isn't covering every reasonable case where the connectivity should be preserved - I didn't think about it very hard).

Regards,

Andrew.

Andrew Beckett said:

It does clean up by default (certainly VLS XL).

Hi Andrew,

Somehow I see the cleaning does not happen by default.  We have some poorly written scripts which fall prey for these stray nets and terminals.

Andrew Beckett said:

mapcar('dbDeleteObject setof(net cv~>nets !(net~>instTerms || net~>term || net~>figs)))

I will consider the above line of script. Wondering why you dropped "nets~>pin" from the condition. Is that "net~>term" is inclusive of "net~>pin"?

Thanks.

-Ramakrishnan

Ramakrishnan,

If you really have some nets which aren't removed which should be, you should contact customer support.

I removed the net~>pins because if there are any net~>pins then there would also be net~>term for the terminal associated with that pin. However, it is possible that you could have a terminal without a pin (if the pin has not been gen from sourced yet, or has been deleted temporarily). So checking for nets with a terminal as opposed to just those with pins is a safer check.

Regards,

Andrew

Ok. Thank you.

Ok. Thank you.