[llvm] [InstCombine] Fold `(x == y) ? 0 : (x > y ? 1 : -1)` into `ucmp/scmp(x,y)` (PR #107314)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM

@dtcxzyw Would be great if you could test this, in case it surfaces more optimization regressions...

https://github.com/llvm/llvm-project/pull/107314