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

Diego Biurrun diego
Mon Sep 17 17:18:29 CEST 2007


On Mon, Sep 17, 2007 at 10:03:56AM -0500, Derek E. Lewis wrote:
> 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.

All the other tests are done with inline assembler and we have inline
assembler in libavcodec/sparc/*.c.  IOW, this is not a problem.

Diego




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