[PATCH] D52177: [InstCombine] Fold ~A - Min/Max(~A, O) -> Max/Min(A, ~O) - A

[Sanjay Patel via Phabricator via llvm-commits]

spatel accepted this revision.
spatel added a comment.
This revision is now accepted and ready to land.

In https://reviews.llvm.org/D52177#1245359, @dmgreen wrote:

> > Craig's been fighting infinite loops in this area, so let's see if he has any comments on the safety constraints.
>
> Any suggestions on finding these? I've run the testsuite and a bootstrap, I presume that wouldn't catch much?


That's a good first try, but the earlier cases escaped to the wild...though not for long. :)
We end up being able to reduce the problems to relatively short IR tests which seem obvious in hindsight, but I don't know how to spot them in advance any better than what we've done.
I don't have any other feedback, so LGTM.


https://reviews.llvm.org/D52177