[llvm] [InstCombine] Fold icmp of trunc nuw/nsw (PR #90436)

[Nikita Popov via llvm-commits]

nikic wrote:

> We should handle `icmp pred (trunc nsw/nuw X), C` first to avoid regression https://github.com/dtcxzyw/llvm-opt-benchmark/pull/567/files#r1583426017.

There is a PR for that one already here: https://github.com/llvm/llvm-project/pull/87935

https://github.com/llvm/llvm-project/pull/90436