tree 4eeea793d58fef41007a91527f64ed5eda003dce
parent 2210767c3f7ce179ea9b352c8de2790b23487bca
author Deb Mukherjee <debargha@google.com> 1334247843 -0700
committer Deb Mukherjee <debargha@google.com> 1335247372 -0700

Differential encoding of probability updates

Adds differential encoding of prob updates using a subexponential
code centered around the previous probability value.
Also searches for the most cost-effective update, and breaks
up the coefficient updates into smaller groups.

Small gain on Derf: 0.2%

Change-Id: Ie0071e3dc113e3d0d7ab95b6442bb07a89970030