[PATCH] D38566: [SimplifyCFG] don't sink common insts too soon (PR34603)

[Hal Finkel via Phabricator via llvm-commits]

hfinkel added a comment.

> This is a minimal patch to solve PR34603:
>  https://bugs.llvm.org/show_bug.cgi?id=34603

Can you please summarize here what's going on and how you arrived at this solution? Last I recall, in PR34603, we were discussing select formation, and how it might not be desirable to form selects early. By "aggressive flattening" do you mean select formation? What you're doing here seems like more than just disabling select formation, but sinking? I also think that we might not want to sink early, at least some things (because we can't later prove it safe to re-hoist), but it's not immediately clear how all of these things are related.


https://reviews.llvm.org/D38566