[PATCH] D35804: [BPI] Detect branches in loops that make themselves not taken

[John Brawn via Phabricator via llvm-commits]

john.brawn added a comment.

> How confident are you in this increase? Is this noise? An actual 2% increase in compile time seems expensive for what this is doing.

Not very. I've finally gotten around to getting more measurements, and the result from building the LLVM test suite 10 times (average combined build time of all objects on my machine, 95% confidence intervals) is: before 741s +/- 6s, after 746s +/- 9s. So I would guess this means there's no overall difference, given that each amount lies within the confidence interval of the other plus looking at the individual objects there's none where the confidence intervals don't overlap, but I have little experience in interpreting these kinds of statistics.


Repository:
  rL LLVM

https://reviews.llvm.org/D35804