[Mlir-commits] [mlir] [SCF] add debug label for MergeNestedParallelLoops pattern (PR #135980)

[Scott Manley]

rscottmanley wrote:

> I have no objections to the patch itself, but it's not very robust. 

Perhaps - I am probably not going to sign up to add a name to every Pattern that exists. I would maybe say it provides an example for others should they want to do something similar.

> If you really want to prevent nested loops merging I would suggest instead of using custom attributes on parallel op, introduce a custom region op to encode info

Yes, that's exactly what I was trying to avoid doing. To me this just introduces its own set of challenges to workaround. E.g. if you were hoist an operation out of the inner loop, does it/should it go into the region op or into the  body of the outer loop? Some existing xforms don't work unless they have the same parent region, etc.

https://github.com/llvm/llvm-project/pull/135980