[PATCH] D26359: Use LiveRangeCalc to extend live ranges in shrinkToUses

[Krzysztof Parzyszek via Phabricator via llvm-commits]

kparzysz added a comment.

I'm not sure if this patch needs any more work, it worked fine when I posted it (at least in my tests).  Since it's been a while ago, it would be worthwhile to make sure that it still does.  It's unfortunate that I didn't have a testcase to illustrate the problem I mentioned in the description, I'm wondering if it would still fail.

Your scenario seems like a problem of a different nature. This patch is trying to fix cases of valid situations not being handled correctly, in your case the situation seems wrong to begin with: every use (except undef uses) must be jointly dominated by the union of explicit defs and undefs.  Trying to extend a range to an index outside of that joint dominance it an error, and this patch is not intended to deal with this.

Please check in detail how the problem happens: try to narrow down the area in the live interval code where a correct liveness information somehow becomes incorrect (or is interpreted incorrectly).  That is critical to developing a proper fix.


Repository:
  rL LLVM

https://reviews.llvm.org/D26359