[PATCH] D29320: [XRay] A tool for Comparing xray function call graphs

[Alexis Shaw via Phabricator via llvm-commits]

varno added a comment.

Just doing the math now, (A/B - B/A)*100 is exactly 2x the average of x and y where x and y are defined such that :
A is x% faster than B, and B is x% slower than A. So this is really a reasonable relative difference function even intuitively, being the average of the two difference metrics.

(x = (A/B - 1)*100 and y= -(B/A - 1)*100, so (x+y)/2 = (A/B - B/A)/2)


https://reviews.llvm.org/D29320