tree 91cb7c4e067df9bed4f3a1f6f976877f9e286728
parent 205532f3a76752bec3a8b4d229c5fbf569b29922
author Johann <johannkoenig@google.com> 1440694542 -0700
committer Johann <johannkoenig@google.com> 1440701918 -0700

Add sse2 versions of halfpix variance

These were lost in the great sub pixel variance move of
6a82f0d7fb9ee908c389e8d55444bbaed3d54e9c

Not having these functions caused a ~10% performance regression in
some realtime vp8 encodes.

Change-Id: I50658483d9198391806b27899f2c0d309233c4b5