gcc 3.2 altivec options and glibc

Daniel Egger degger@fhm.edu
Mon Aug 26 04:05:00 GMT 2002


Am Son, 2002-08-25 um 18.28 schrieb Jack Howarth:

>    Okay. I had been looking over glibc/sysdeps/powerpc/fpu and
> those routines, at first glance, seemed not to be specificly
> using assembly for the fpu so I was curious if one could recompile
> them to run on the altivec instead. Guess not...

No, not. And actually I doubt that one could gain very much by adding
altivecized routines because vectorized routines happen to be
only fast for large(r) datasets and parallelizeable algorithms of which 
you'll find very few in glibc. That idea is not even suitable for
parallelisable functions like memcpy because the alignment restrictions
can hardly be enforced on the source and destination parameters which
means either more specialcases or general aligning data which wouldn't
leave any speed improvements.

-- 
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.7 (GNU/Linux)

iD8DBQA9aUy/chlzsq9KoIYRAsWBAKCtnaUV1szr3ULdlynyTHXQQarZJgCfe7uV
SdFUSWBHr9hS+jbGuuvIGbU=
=9eZt
-----END PGP SIGNATURE-----


More information about the Gcc mailing list