[PATCH] D70975: [SDAG] remove use restriction in isNegatibleForFree() when called from getNegatedExpression()

Wed Dec 11 13:05:34 PST 2019

fhahn added a comment.

In D70975#1780280 <https://reviews.llvm.org/D70975#1780280>, @spatel wrote:

> In D70975#1780237 <https://reviews.llvm.org/D70975#1780237>, @fhahn wrote:
>
> > This seems to cause a DAGCombiner to not terminate for some inputs on AArch64. Unfortunately I cannot share the inputs that cause the cycle :(
>
>
> Thanks for letting us know. Can you check if D70595 <https://reviews.llvm.org/D70595> would cause the same cycle?
>  Will it be possible to reduce a test that can be shared? I'm not sure how to proceed without a test.

I'll see if I can reduce it tomorrow! I looked at the debug output and it seems the cycle is quite simple.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D70975/new/

https://reviews.llvm.org/D70975