Re: hwcap support for AMD64?

["Marcelo E. Magallon" <mmagallo@debian.org>]

On Wed, Dec 29, 2004 at 01:05:36AM +0100, Kurt Roeckx wrote:

 > >  I'm repacking Mesa and I'd like to support architecture-optimized
 > >  libraries along with the regular ones.  Does amd64 support hwcaps?
 > >  If yes, what's the ld.so search path?
 > 
 > What are "hwcaps"?  Do you plan to have seperate binaries for the k8
 > (amd64) and nocoda (intel) cpus?

 That's what "hwcaps" are.

 I don't know what I want to support :-)

 For now the library in /usr/lib/libGL.so.1 is compiled using -O2 and
 nothing else.  Neither MMX nor SSE can be used because even if the
 assembler code is mostly compatible (AFAICR a slight change is needed,
 but I don't have my code handy and my memory is lousy, so I don't
 remember what this change is).  It doesn't use 128-bit media
 instructions either, which would be more appropriate in this case (and
 more of a speed boost).

 Now that I think of it, it doesn't make much sense to have hwcaps on
 this platform since it refers practically to a single CPU.

 I personally don't care for Intel CPUs but if someone is willing to
 test on that platform (which AFAICT gcc 3.3 does not support) and
 provide a configuration file (this would require less than 10 minutes
 for someone who knows what he's doing) I'll gladly include it in the
 build.

 > Yes, it defaults to 64 bit.

 Thanks,

 Marcelo