code review 6625058: image/jpeg: move the huffman bit decoder state higher u...

image/jpeg: move the huffman bit decoder state higher up in the
decoder struct, inside the unmappedzero limit, to eliminate some
TESTB instructions in the inner decoding loop.

benchmark          old ns/op    new ns/op    delta
BenchmarkDecode      2943204      2746360   -6.69%

[nigeltao, 2012-10-07 03:31:30]

Hello r@golang.org (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://go.googlecode.com/hg/

[dave_cheney.net, 2012-10-07 04:14:23]

On 2012/10/07 03:31:30, nigeltao wrote:
> Hello mailto:r@golang.org (cc: mailto:golang-dev@googlegroups.com),
> 
> I'd like you to review this change to
> https://go.googlecode.com/hg/

LGTM. Very interesting catch.

[r, 2012-10-07 05:22:22]

LGTM

[nigeltao, 2012-10-07 08:32:35]

*** Submitted as http://code.google.com/p/go/source/detail?r=7b037816cd5c ***

image/jpeg: move the huffman bit decoder state higher up in the
decoder struct, inside the unmappedzero limit, to eliminate some
TESTB instructions in the inner decoding loop.

benchmark          old ns/op    new ns/op    delta
BenchmarkDecode      2943204      2746360   -6.69%

R=r, dave
CC=golang-dev
http://codereview.appspot.com/6625058