[llvm] [SCEV] Fold (C1 * A /u C2) -> A /u (C2 /u C1), if C2 > C1. (PR #157656)

[Augie Fackler via llvm-commits]

durin42 wrote:

Sorry, life got in the way and I'm just back to this. Yes, it looks like it's probably a miscompile leading to a segfault in rustc: it only happens in a stage2 compiler, and the tracebacks don't seem to have any LLVM frames in them.

I'm not really sure what to do in terms of reducing the failure tho. rustc is pretty big.

https://github.com/llvm/llvm-project/pull/157656