From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Egger To: Jack Howarth Cc: GCC Developer Mailinglist , drow@mvista.com Subject: Re: gcc 3.2 altivec options and glibc Date: Mon, 26 Aug 2002 04:05:00 -0000 Message-id: <1030311104.16146.9.camel@sonja.de.interearth.com> References: <200208251628.MAA58968@bromo.msbb.uc.edu> X-SW-Source: 2002-08/msg01582.html 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-----