Support gziped Liberty files

[hpretl]

Feature Description

Happy New Year, YosysHQ team! Please keep up the excellent work you are doing!

It looks like (I haven't tested myself) that Yosys is already supporting gzip'ed Verilog files. It would be equally useful to support gzip'ed Liberty (.lib.gz) files, as having zipped Liberty files in the PDK setup would be a big help for space reduction.

See also efabless/openlane2#627

[donn]

Yosys does support gzipped liberty files, it's our Yosys script that emitted that error :)

[hpretl]

Sounds good, then looks like we could have .gz support soon in OL2 :-)

[povik]

Thanks and happy new year to you too!

Yosys does support gzipped liberty files

It does support them for read_liberty, not for abc -liberty or dfflibmap -liberty. @widlarizer happens to be looking into this.

[hpretl]

@widlarizer +1 for nickname :-)

[hpretl]

OL2 is almost released with.gz support (planned for 2.3.2 version). @widlarizer Do you have a timeline for full .gz support rolled into a Yosys release?

[donn]

We wouldn't include something as major as a Yosys upgrade in a patch version btw

[gadfort]

dfflibmap and the clockgate command would also need to be able to support a dont use list, otherwise to enable that we still have to preprocess the file.

[povik]

I think both do already (at least as of master)

[gadfort]

@povik thanks for clarifying, I hadn't seen that

[gadfort]

@povik is there a plan to support multiple liberty files on these commands as well? (like abc)?

[povik]

Yes, there is. Btw as @widlarizer points out in the linked PR, for abc -liberty to accept gzipped Liberty files we need to change ABC, not Yosys. We don't have concrete plans to do that yet. If anyone in the community wants to pick this task up please let the Yosys team know.

[gadfort]

@povik one possibility would be to extract the files into the tmp directory that abc is running in if the liberty file has a .gz extension (avoiding the need to update ABCs support)

[povik]

Right, we already prepare a bunch of temp files for ABC. Though it's suboptimal for those PDKs where the Liberty files are excessively large but at least it gets us something in the short term.

[hpretl]

@povik I think the approach with extract to /tmp would be a good compromise to get this in reasonable short time, and have mid-term abc prepared for .gz support.

[widlarizer]

@gadfort

is there a plan to support multiple liberty files on these commands as well? (like abc)?

We're streets ahead of ya: #4797, sorry it didn't make it into the release notes!

[gadfort]

@widlarizer even better :-)