[FFmpeg-devel] [PATCH] fix compiling VIS assembly on SPARC

[Derek E. Lewis]

On Mon, 17 Sep 2007, Diego Biurrun wrote:

> It would be nice if somebody could provide us some VIS detection code
> for configure.  It should be trivial to do, but it's better to have a
> machine for testing it on...

If you had in mind just compiling some C source that contained, common VIS 
inlined functions, this could be a problem, as such inlined functions are 
only available with the VIS SDK, which is not included by default on 
systems. We'd need to do inline assembly, which is compiler-dependent.

Solaris systems provide an isainfo(1) command, which lists the instruction 
sets the system supports. We'd need to do some sed/grep magic, but that's 
simple enough. The downside is that 'configure' would only be able to 
detect VIS on Solaris systems.

The most operating-system independent way would be inline assembly, as 
mentioned above, but we risk losing compatibility with other compilers 
(not that it matters at the moment on SPARC, where gcc is the only 
compiler that'll compile MPlayer/FFmpeg, anyway). If there's already a 
precedent for this in the x86 port, then I would support it.

Derek E. Lewis
dlewis at solnetworks.net
http://delewis.blogspot.com