[llvm] Reapply [X86][ARM] Invert the low bit to get the inverse predicate (NFC) (PR #152053)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

TBH I don't like this obfuscation, it makes it harder to debug and I doubt if they are a performance bottleneck.

https://github.com/llvm/llvm-project/pull/152053