tree 72c5e9ac61800b8ad76e507612740d98ef5ab89f
parent dea3e89983f299b3325898fa5b9474be258553b2
author Vincent Rabaud <vrabaud@google.com> 1538141545 +0200
committer Vincent Rabaud <vrabaud@google.com> 1540034630 +0200

Speedups for empty histograms.

When histograms are empty, it is easy to add them.
They should also not be considered when merging histograms
(it is a waste of CPU).
This does not change the compression performance,
just the speed.

Change-Id: I42c721ca0f9c5ea067e73b792aa3db6d5e71d01f