[llvm] [LV] Add support for partial reductions without a binary op (PR #133922)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

Now that the change for bundle/expression recipes landed, https://github.com/llvm/llvm-project/pull/146073 should also be good land soon.

As long as we are confident that https://github.com/llvm/llvm-project/pull/146073 will help simplify the cost implementation we don't necessarily wait for it to land. 

Left a few additional comments inline.

https://github.com/llvm/llvm-project/pull/133922