[llvm] [VectorCombine] Support pattern `bitop(cast(x), C) -> cast(bitop(x, InvC))` (PR #155216)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

SGTM although I'd prefer we start just with bitcast and then add trunc/sext/zext later patches in case there's a flaw in the FMF handling that I've missed.

https://github.com/llvm/llvm-project/pull/155216