[PATCH] D25691: [DAGCombiner] Add vector demanded elements support to computeKnownBits

[Bjorn Pettersson via llvm-commits]

bjope added a comment.

No further comments from me.

But I agree with earlier comments that it could be nice if the computeKnownBits (and probably also computeNumSignBits) in both InstCombine and SelectionDAG could share same infrastructure. I guess that sometimes we want to do similar updates to those methods, and that is probably easier if they at least are kept fairly in sync about how they work and what operations they can handle.
But changing everything in one commit is not so wise either. So this commit looks like a good first step when it comes to adding support for "demended elts".


Repository:
  rL LLVM

https://reviews.llvm.org/D25691