[llvm] [SCEV] Collect guard info for ICMP NE w/o constants. (PR #160500)

[Nikita Popov via llvm-commits]

https://github.com/nikic commented:

Unfortunately, it looks like this has a large compile-time impact: https://llvm-compile-time-tracker.com/compare.php?from=8c6b499f066e2b39da1936e0f9ef994fcf0884b3&to=2d027260b0f8ef9b2e0b2fc8c254b2b8da0ae4f7&stat=instructions:u

I guess that speculatively computing this getMinusSCEV without knowing whether it occurs is expensive.

https://github.com/llvm/llvm-project/pull/160500