[PATCH] D89381: [SCEV] Re-enable "Use nw flag and symbolic iteration count to sharpen ranges of AddRecs", attempt 3

Tue Oct 27 05:49:41 PDT 2020

lebedev.ri accepted this revision.
lebedev.ri added a comment.

@nikic any reason for this compile time re-measuring dance instead of explaining the onboarding process?
(I.e. telling https://github.com/max-azul to make a github fork off https://github.com/llvm/llvm-project
into https://github.com/max-azul/llvm-project and adding that as a tracked remote for http://llvm-compile-time-tracker.com/ ?
(then, push branch to be measured as `perf/<...>`, and it will get measured))

Current numbers: (+0.6% geomean)
https://llvm-compile-time-tracker.com/compare.php?from=0ac56e8eaaeb41b59a952fa465872f647c930347&to=b36e80eaf4b4e35c74d814babe722160ef164f9b&stat=instructions

In D89381#2355899 <https://reviews.llvm.org/D89381#2355899>, @mkazantsev wrote:

> @nikic @MaskRay any reasons to keep this out? It's effectively an NFC now. If we want to further measure its impact on compile time & performance of clang benchmarks, it can be a separate change switching the flag value.

I don't see any reasons, especially if this doesn't change the default just yet.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D89381/new/

https://reviews.llvm.org/D89381