dialects: (scf) Add IsTerminator to scf.reduce

[AntonLydike]

Add IsTerminator to scf.reduce op as per upstream

[alexarice]

I looked at this last week, upstream is significantly different, and in the pinned version of mlir scf.reduce is not a terminator I believe

[JosseVanDelm]

It indeed became a terminator after the current MLIR version that is pinned:
llvm/llvm-project#75314

I have no clue whether this is a big issue though?
Are there a lot of people who require stuff to be after an scf.reduce po?

[superlopuh]

This seems like a slippery slope, couldn't we just update MLIR version instead? I would just suggest doing that after the CGO deadline

[alexarice]

If my understanding is correct, then in the pinned mlir version you can have multiple scf.reduce operations in one scf.parallel, which would not be possible if it were a terminator. The up to date mlir version has been changed so that you can attach multiple regions/arguments. I don't really have any stake in this but it seems like a bad idea to make some strange hybrid scf.reduce op?

[AntonLydike]

Yes, sorry, meant to close this earlier!