[PATCH] D42088: [x86] shrink 'and' immediate values by setting the high bits (PR35907)

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

I wonder if we should do this in PreprocessISelDAG so the killing off of the AND when the mask is all 1s doesn't seem quite so weird. Right now when it happens the Select call ends up doing selection on the input to the AND.


https://reviews.llvm.org/D42088