[Mlir-commits] [mlir] [mlir][GPU] Fixes subgroup reduce lowering (PR #141825)

[Krzysztof Drewniak]

krzysz00 wrote:

> Please explain what types of erroneous results can occur, providing an example.

To summarize the debugging situation - and to potentially provide language for the PR description - "the final reduction steps were taken from an implementation of scan, not reduction, causing lanes earlier in the wave to have incorrect results due to masking"

https://github.com/llvm/llvm-project/pull/141825