[FFmpeg-devel] [PATCH]Fix h264 decoding for icc 32 bit on sse2 cpu

Reimar Döffinger Reimar.Doeffinger
Fri Dec 26 11:46:15 CET 2008

On Fri, Dec 26, 2008 at 10:15:53AM +0000, M?ns Rullg?rd wrote:
> > The assembly functions require stack alignment which ICC apparently
> > doesn't provide.
> I keep hitting such problems on ARM as well, especially with armcc.
> This reliance on a nonstandard, and largely undocumented, feature of
> gcc is worrying.

Just to clarify: the issue is not relying on stack _variables_ being
aligned, ICC handles that fine to my knowledge, it is that the yasm code
seems to assume that the stack pointer itself is aligned.
I forgot to ask last time: Why? Would the three instructions to fix this
really cause a noticeable performance difference?

Reimar D?ffinger

More information about the ffmpeg-devel mailing list