[PATCH] D21774: [X86] Transform setcc + movzbl into xorl + setcc

[Ahmed Bougacha via llvm-commits]

ab added a subscriber: MatzeB.
ab added a comment.

+1 to David's comments about the weirdness around the dependencies.  I'm not sure how much of a problem that is in practice though, since that sounds like a pessimization that goes against register coalescing regardless of the specifics of this patch.

Speaking of which;  I looked a little closer at the ISel approach, and, with Matthias's and Quentin's help, I have a patch that looks like it works?  Can you give it a try: http://reviews.llvm.org/D21822


http://reviews.llvm.org/D21774