✨ Add absorb-swaps pass

[jmoosburger]

Description

• add new qco pass as warmup task (in cooperation with @MatthiasReumann)
• remove leading swap-gates in a circuit
• reorder static qubits instead

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[jmoosburger]

@MatthiasReumann

works fine now 💪
nice setup with the CMakePresets by the way... :)

i have another conceptional question though: which of the following circuits is correct?

circuit 120

q0 ----X---------- q1
       |
q1 ----X----X----- q2
            |
q2 ---------X----- q0

or:

circuit 201

q0 ----X---------- q2
       |
q1 ----X----X----- q0
            |
q2 ---------X----- q1

in my opinion its the second circuit 201, but the implementation we discussed produces the first result.
i just wanted to make sure that i'm correct in my assumption before i fix it :)

[jmoosburger]

the linter produces warnings on the one hand, but failes because of a http-error 403 (unauthorized) on the other hand. see here: https://github.com/munich-quantum-toolkit/core/actions/runs/26597942119/job/78373906843?pr=1750

is there anything i can do about it?

[denialhaag]

the linter produces warnings on the one hand, but failes because of a http-error 403 (unauthorized) on the other hand. see here: https://github.com/munich-quantum-toolkit/core/actions/runs/26597942119/job/78373906843?pr=1750

is there anything i can do about it?

Unfortunately, the action cannot post comments on PRs coming from a fork. 😕

That said, the report can also be found in the summary of the run: https://github.com/munich-quantum-toolkit/core/actions/runs/26597942119/attempts/1#summary-78373906843

[MatthiasReumann]

@jmoosburger

i have another conceptional question though: which of the following circuits is correct?

The best way to visualize this is to apply the SWAPs sequentially:

circuit 120

q0 ----X-- q1 ------------ q1
       |
q1 ----X-- q0 --X-- q2 --- q2
                |
q2 -------------X-- q0 --- q0

[jmoosburger]

the linter produces warnings on the one hand, but failes because of a http-error 403 (unauthorized) on the other hand. see here: https://github.com/munich-quantum-toolkit/core/actions/runs/26597942119/job/78373906843?pr=1750
is there anything i can do about it?

Unfortunately, the action cannot post comments on PRs coming from a fork. 😕

That said, the report can also be found in the summary of the run: https://github.com/munich-quantum-toolkit/core/actions/runs/26597942119/attempts/1#summary-78373906843

so if i resolve all the warnings the lint check will succeed, as it does not post a comment?

[MatthiasReumann]

so if i resolve all the warnings the lint check will succeed, as it does not post a comment?

If you resolve all warnings the CI / Lint / 🚨 Lint (pull request) workflow will succeed. The pull request will look like this one.

[jmoosburger]

so if i resolve all the warnings the lint check will succeed, as it does not post a comment?

If you resolve all warnings the CI / Lint / 🚨 Lint (pull request) workflow will succeed. The pull request will look like this one.

Which way is recommended?
the contribution.md suggests clang-tidy and the section Development Setup in installation.md suggests nox -s lint...

[jmoosburger]

@jmoosburger If you think the pull request is ready to review, feel happy to request a review from someone (me) for on the top right of the pull request page.

Unfortunately i cannot edit the reviewers-section °^^

But i recognized, i need to add a summary and a description for the new pass first ☝️

[jmoosburger]

But i recognized, i need to add a summary and a description for the new pass first ☝️

I added a rather short description as i think it's not that complicated. feel free to share your personal opinion on that!

[MatthiasReumann]

It took us a pretty long time and three pull requests but we are finally here! Congratulations on your potentially first contribution to the MLIR compiler collection 🎉

I've left some small remarks which should be fairly easy to integrate. Otherwise, great job! 🚀

[jmoosburger]

It took us a pretty long time and three pull requests but we are finally here! Congratulations on your potentially first contribution to the MLIR compiler collection 🎉

I've left some small remarks which should be fairly easy to integrate. Otherwise, great job! 🚀

Thanks for your help and patience!
Hopefully there will be more in the future 🥳

[MatthiasReumann]

@jmoosburger I've pushed some minor changes directly.

Let's see what @burgholzer has to say, but I think this one should be good to go 🚀