[PATCH] D21720: Unroll for uncountable loops

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

>> Conversely, unrolling a large loop just to eliminate one branch is probably a bad idea.
>  That is bounded by thresholds.

Not really... I mean, we have PartialThreshold as a maximum size for the whole unrolled loop, but that isn't sensitive to the dynamic cost savings.  (Compare to getFullUnrollBoostingFactor for complete unrolling.)


Repository:
  rL LLVM

https://reviews.llvm.org/D21720