[PATCH] D46581: [DAGCombine] Change store merge candidates check cut off to 1024

[Nirav Dave via Phabricator via llvm-commits]

niravd accepted this revision.
niravd added a comment.
This revision is now accepted and ready to land.

I think pruning this back is reasonable. The choice of 8192 was arbitrary.  Have you checked larger sizes than 1024? Given it's a 5x increase (presumably) of the total runtime and the algorithm is O(N) I would expect to only need a 5x reduction and 2048 would be roughly equivalent.

Also, since you've run the spec benchmarks, can do a quick check to see which binaries changed? This search could be rewritten to bound this search to the true common ancestor but there's no point in rewriting it unless there's a valid merging case where we give up early.

Either way this LGTM.


Repository:
  rL LLVM

https://reviews.llvm.org/D46581