flag_missing_ports flags all internal nets for source subcircuits with no ports

Open
  • Is something wrong?
#2,138 5 comments 0 reactions 0 assignees View on GitHub

Maintainers usually reply within 1 day

Nobody has claimed this yet.

Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp, python
Domain
tooling

Research direction

Start by reading the flag_missing_ports implementation and its flag_missing_port helper, then run the IHP-Open-PDK regression command from the issue. Focus on the case where the source SPICE top cell has no ports. Done means that case no longer reports internal nets as ports or produces the resulting mismatch.

Written by the indexing model from the issue text.

Description

question

Requires at least klayout 0.30.2 (flag_missing_port helper routine).

@klayoutmatthias Thanks for the port check enhancement. That has helped find discrepancies in standard cell port labeling.

However, we noticed that when the source spice top cell has no ports, then all of the internal nets are considered ports and cause a mismatch.

Image

You can verify this with the IHP-Open-PDK repo test cases.

git clone https://github.com/H-Ojiro/IHP-Open-PDK.git --depth=1 -b port_check
cd IHP-Open-PDK/ihp-sg13g2/libs.tech/klayout/tech/lvs/testing
python3 run_regression.py RES

Here's the spice

.SUBCKT rppd
Rp1 net1 net2 rppd m=1 l=0.5u w=0.5u
Rp2 net3 net4 rppd m=1 l=1u w=0.5u
Rp3 net5 net6 rppd m=1 l=1.2u w=0.7u
Rp4 net7 net8 rppd m=1 l=1.5u w=0.5u ps=0.2u b=1
Rp5 net9 net10 rppd m=1 l=1.7u w=0.5u ps=0.2u b=2
...

The layout has no text.

CC: @H-Ojiro

Dominant language
C++
Stars
1.2k
Forks
305
Avg merge
3d 2h
Merged PRs (30d)
11

Getting set up

This project ships no dev container, Dockerfile or contributing guide, so setting up is up to you: start from its README, and see our first-contribution guide for the general steps.

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from KLayout/klayout

All issues in KLayout/klayout

Similar issues

More C++ issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.