[PATCH] D39402: [X86] Prevent fast isel from folding loads into the instructions listed in hasPartialRegUpdate.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

I don't think this makes fast isel slower rather it make sure the fast isel entry point does this check. (at least the one used by X86FastISel::tryToFoldLoadIntoMI). So it actually may slow down peephole folding and spill folding. Maybe I should just leave the other checks in place and add a new one?

I'm not sure what tests we have for the optsize. I'm pretty sure we don't have any for fast isel but not sure about SDAG.


https://reviews.llvm.org/D39402