[FFmpeg-devel] [PATCH] ff_scalarproduct_float_sse

Reimar Döffinger Reimar.Doeffinger
Wed Jan 20 22:21:14 CET 2010

On Wed, Jan 20, 2010 at 03:43:25PM -0500, David Conrad wrote:
> On Jan 20, 2010, at 1:39 PM, Reimar D?ffinger wrote:
> > On Wed, Jan 20, 2010 at 08:59:44AM -0800, Jason Garrett-Glaser wrote:
> >> Furthermore, do note that all current non-yasm SSE assembly in ffmpeg
> >> is broken on Win64...
> > 
> > How and why? I may just not have run into it (not tested much), but my Win64
> > MPlayer build seemed to work fine.
> Win64 ABI has several xmm registers as callee-saved, and none of the inline asm marks them as clobbered.

So it's actually "almost all inline asm has broken constraints".
Which strongly hints at one of the bigger issues with gcc inline
asm, but it is a bug on Linux as well, even if it is unlikely to
have consequences currently.

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