[vsipl++] VSIPL++ availability for PowerPC AltiVec

[Jeff Bateman]

Brooks,

Your prompt response is much appreciated, and has been forwarded to
appropriate VMETRO personnel for consideration. It's great news that
AltiVec is being supported.

One further question: is there any support yet under VxWorks 6.x?


Jeff Bateman, Senior Systems Engineer

VMETRO Inc.
171 E. State Street, Suite 275, Box 120
Ithaca, NY 14850-5548
Voice (607)272-5494 ext. 22    Fax (607)272-5498
jbateman at vmetro.com    http://www.vmetro.com
-----Original Message-----
From: Brooks Moses [mailto:brooks at codesourcery.com] 
Sent: 11 February, 2008 16:10
To: Jeff Bateman
Cc: vsipl++ at codesourcery.com
Subject: Re: [vsipl++] VSIPL++ availability for PowerPC AltiVec

Hello, Jeff,

Jeff Bateman wrote, at 2/11/2008 12:28 PM:
> Please advise - is VSIPL++ available for AltiVec? Or, might it be
ported
> to AltiVec in the (near) future?

Yes, Altivec is supported, and we will be producing a PowerPC-Altivec
binary package as part of the upcoming 1.4 release.

VSIPL++ contains some internal SIMD code, and also depends heavily on
the BLAS, LAPACK, and FFTW libraries that it is linked with for the
back-end computation, so as long as you compile the VSIPL++ library and
your code with the relevant compiler options and link with Altivec
versions of those libraries, you should see the library making good use
of the Altivec extensions.

Fedora 7 provides Altivec-enabled versions of ALTAS as standard RPMS
("atlas-altivec" and "atlas-altivec-devel"); we've had success linking
against those, using the following configure options:

  --with-lapack=atlas  --with-atlas-include=/usr/include/atlas
  --with-atlas-libdir=/usr/lib/altivec

(Note the libdir option in particular; Fedora also has a non-Altivec
ATLAS that goes in /usr/lib, which would be used if you don't explicitly
point to the /usr/lib/altivec ones.)

Also, I believe that the standard Fedora FFTW3 packages ("fftw" and
"fftw-devel") use Altivec as well.  The configure flag to link against
those is simply:

  --enable-fft=fftw3

Finally, for GCC you will want to include

  CXXFLAGS="-maltivec"

in the configure line; other compilers will need an equivalent option
unless they enable Altivec extensions by default.

Hope that helps, and let us know if you have further questions!

Thanks,
- Brooks