[PATCH] D42717: [JumpThreading] sync DT for LVI analysis (PR 36133)

[Daniel Berlin via Phabricator via llvm-commits]

dberlin added a comment.

LVI functions fine without DT, and it's going to be too expensive to ever use a lazy analysis  that is constantly recomputing info like LVI because it may require hundreds or thousands of Dominator tree rebuilds.  I would hand LVI a fake dt pointer class where when the Dominator tree is up to date, it works and when it's not up to date, it is null. That would work with how LVI currently checking I think. Regardless I think the right answer here is to make it not use it when it's not up to date.  That will give better answers then it used to get and you get gradually better answers as you can preserve more or become less lazy


Repository:
  rL LLVM

https://reviews.llvm.org/D42717