This change seems to restore performance to
the level before CL 108140045.
benchmark old ns/op new ns/op delta
BenchmarkDecodeVP8SimpleFilter 796416 784394 -1.51%
BenchmarkDecodeVP8NormalFilter 4931138 4693078 -4.83%
BenchmarkDecodeVP8L 7820030 7821796 +0.02%
LGTM=nigeltao, r
R=nigeltao, r
CC=golang-codereviews
https://golang.org/cl/107340047
The benchmarks are a little slower, but the code is shorter.
benchmark old ns/op new ns/op delta
BenchmarkDecodeVP8SimpleFilter 621950 644184 +3.57%
BenchmarkDecodeVP8NormalFilter 4045745 4269431 +5.53%
LGTM=r
R=r, minux, ruiu
CC=golang-codereviews
https://golang.org/cl/108140045