Small LVS issues #1719
Description
Some small LVS issues have been found.
-
same_nets!("*", "*")should ignore unnamed nets in the net selection expression. For the motivation, see here: https://www.klayout.de/forum/discussion/2503/detecting-swapped-pins -
connect_implicit("*", "*")should ignore floating nets -
Some way to name layers is needed
For the second request the motivation comes from an observation made with the Sky130 standard cells: some carry multiple labels on "pwell.drawing". As these labels participate in "connect" statements, they generate floating nets. Requesting connect_implicit("*", "*") (aka "must connect all") reports them as disconnects nets for now.
The motivation for the third request is the ability to restore layer geometries from a LayoutToNetlist database. Without proper naming of derived layers, they receive arbitrary names (such as "l39") which depend on the order they appear in the LVS script. Such names are hard to use as identifiers as they would change often or depending on script switches.