[Kernels] Add an inductor pass to rewrite and fuse collective communication ops with gemms (WIP not for review)

[bnellnm]

Add an inductor pass to rewrite and fuse collective communication ops with gemms.

This branch and PR contain the changes to the llama model that we want to avoid by using the inductor pass. I'm keeping them around since they are good for baseline testing.

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. @bnellnm please rebase it. https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[hmellor]

Hi @bnellnm, can this PR be considered superseded by #9886?

[bnellnm]

hmellor

Not exactly. This draft has an alternate implementation that was useful for getting baseline data.

[hmellor]

Understood. I have been clearing the backlog of Issues and PRs and thought this one might be closable.

Are you happy for this to be closed?