Autor: salsaman Fecha: A: Minimalistic plugin API for video effects Asunto: Re: [Frei0r] [PATCH] Optimize the balanc0r plugin using SSE2
On Sat, Sep 15, 2012 at 7:48 AM, Steinar H. Gunderson
<sgunderson@???> wrote: > On Fri, Sep 14, 2012 at 10:47:23AM -0700, Dan Dennedy wrote:
>> Thank for you trying to help. To other committers, please do not apply
>> this because there is uncertainty about its correctness in another
>> thread. In that case, perhaps this should only be changed to somehow
>> indicate it is deprecated. Plus...
>
> Sorry, I didn't see the rest of your comments until now.
>
>>> +#ifdef __SSE2__
>> where is that defined? Looks gcc-specific but also in clang, but is it
>> safe or dependent on some recent version of clang? I know some people
>> have submitted patches to frei0r for msvc. What about that compiler?
>
> GCC sets it if it knows compile-time that your CPU supports SSE2;
> for instance, if compiling for 64-bit, or if -msse2 is given.
> I don't know what MSVC or ICC does, but I couldn't find offhand a
> define for the same thing.
>
> The intrinsics used are the standard Intel intrinsics for SSE2, which as far
> as I know are supported across GCC/Clang/ICC/MSVC.
>
>> I guess it is not too big of deal if last few pixels are skipped when
>> (width * height) is not a multiple of 4.
>
> If it's not a multiple of 4, the last few pixels will be done by the scalar
> loop below.
Shouldn' t be necessary, since the frei0r spec states x and y
dimensions must be multiples of 8 pixels, but if it does no harm then
you might as well leave it in.