Andreas Rheinhardt:
> We currently mostly do not empty the MMX state in our MMX
> DSP functions; instead we only do so before code that might
> be using x87 code. This is a violation of the System V i386 ABI
> (and maybe of other ABIs, too):
> "The CPU shall be in x87 mode upon entry to a
Henrik Gramner via ffmpeg-devel:
> On Wed, Nov 1, 2023 at 10:44 AM Andreas Rheinhardt
> wrote:
>> libavutil/x86/pixelutils.asm | 1 +
>> 1 file changed, 1 insertion(+)
>
> IIRC the emms instructions is quite slow on many systems, so if this
> is the only pixelutils function using mmx it's
On Wed, Nov 1, 2023 at 10:44 AM Andreas Rheinhardt
wrote:
> libavutil/x86/pixelutils.asm | 1 +
> 1 file changed, 1 insertion(+)
IIRC the emms instructions is quite slow on many systems, so if this
is the only pixelutils function using mmx it's probably better to just
rewrite it to use SSE2
We currently mostly do not empty the MMX state in our MMX
DSP functions; instead we only do so before code that might
be using x87 code. This is a violation of the System V i386 ABI
(and maybe of other ABIs, too):
"The CPU shall be in x87 mode upon entry to a function. Therefore,
every function
