Refactor chevron to cub

[ZelboK]

I had a PR here
https://github.com/NVIDIA/cccl/pull/592/files that I forgot about. It would probably easier to just make a new PR instead of trying to rebase that one since it's old.

With that being said to ease burden on the reviewer I've only touched 1 file(for now) and left comments where I am asking questions. If this work isn't needed anymore LMK and I will close both PRs.

Checklist

• New or existing tests cover these changes.
• The documentation is up to date with these changes.

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[ZelboK]

is this namespace cocrrect? i see there's cuda_cub in the thrust launcher

[bernhardmgruber]

I had a PR here
https://github.com/NVIDIA/cccl/pull/592/files that I forgot about. It would probably easier to just make a new PR instead of trying to rebase that one since it's old.

Those are independent things. You could create a new branch locally (with a different name) and force push it to the same branch in your fork, from which the PR was created. You could also just git reset --hard your local branch to our upstream main, start over, and force push. The best thing would still be to rebase your changes. Try to let a good editor/IDE help you. I am sure VSCode has a good merge viewer.

By creating a new PR, you create discontinuity in the review, especially because @gevtushenko already provided a lot of feedback on your old PR, some of which is unaddressed.

[bernhardmgruber]

Independently on where you want to continue your work, this PR seems to add a copy of Thrust's trivple_chevron into CUB. #568 seems to suggest to move the functionality instead, so it should no longer exist in Thrust.

[ZelboK]

Independently on where you want to continue your work, this PR seems to add a copy of Thrust's trivple_chevron into CUB. #568 seems to suggest to move the functionality instead, so it should no longer exist in Thrust.

Yes, I did not remove Thrust's chevron here. That would be the next step. But I wasn't sure if this work was still required, so I decided to ask questions here first. Before progressing further I wanted to make sure this was still needed so I could avoid wasting my time in the case it wasn't. Sorry for not clarifying on that

[bernhardmgruber]

I wasn't sure if this work was still required, so I decided to ask questions here first.

This work seems similar to #2038, so maybe @pciolkosz knows the answer to that.

[ZelboK]

I wasn't sure if this work was still required, so I decided to ask questions here first.

This work seems similar to #2038, so maybe @pciolkosz knows the answer to that.

Thank you. I'll hold off on this one then for now