[FFmpeg-devel] [PATCH] move h264 loopfilter strength code to yasm

[Jason Garrett-Glaser]

On Thu, Sep 23, 2010 at 9:21 PM, Jason Garrett-Glaser
<darkshikari at gmail.com> wrote:
> On Thu, Sep 23, 2010 at 8:18 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
>> On Thu, Sep 23, 2010 at 06:13:30PM -0400, Ronald S. Bultje wrote:
>>> Hi,
>>>
>>> $subj. This could likely be done in inline asm as well but I still
>>> can't write that.
>>
>> can i help you to learn it?
>>
>>
>>> The advantage of the approach to write it fully in
>>> asm is to get rid of gcc doing a pretty bad job at optimizing, e.g.
>>
>> thats great and i dont mind
>>
>> the problem here is that inline ->yasm and further optimizations
>> should be seperate patches and you yourself submitted a patch that repeats
>> this rule, its already in the policy that patches shoudl be cleanly split.
>> and we all know a dozen reasons why that is so.
>
> yasm and inline asm are different languages. ?Asking someone to port
> code from one to the other while keeping it exactly identical is
> stupid; it adds an enormous amount of overhead to the process. ?In
> reality, it isn't really porting; it's rewriting, with some
> inspiration gained from the original code.
>
>> So what should i do?
>> mans, dark shikari, you and everyone else on irc do a witchhunt against
>> inline asm
>
> No, we're submitting patches that improve performance and
> compatibility. ?It just happens that these move inline asm to yasm.
>
> YOU ARE NOT MAINTAINING ANY OF THIS CODE. ?Therefore, you have no
> right whatsoever to reject any of these patches.

Let me elaborate on this in a more detailed fashion.

"Maintain" is an action, not a state of being.  That is, being a
"maintainer" means one of two things:

a) You are actively fixing and improving code.
b) You are not working on code because there aren't any known bugs
with it, but you're on call to work on it if issues arise.

There are multiple known bugs in the h264 decoder, such as the fact
that decoding is broken with threads+slices, and the fact that error
concealment is hilariously broken with missing frames.  Personally, I
hold myself to a very high standard regarding bugs (I try to fix them
within hours of the report).  But even if I'm much more lenient here,
you're hardly a maintainer: the first bug I reported a month ago,
easily, and still haven't gotten any update beyond the original "I'm
too busy".  The second bug I emailed the mailing list about yesterday
and didn't even get a response.

It's fine if you don't have time to do these things.  You have a huge
amount of work to do.  You've saddled yourself with far more than you
have time for.  But if you don't have time to maintain H.264, don't
try to jump into every bikeshed discussion as if you were somehow a
maintainer.

Dark Shikari