Bug#680096: ATLAS on PowerPC

[Lennart Sorensen]

On Wed, Jul 04, 2012 at 09:39:37PM +0200, Sébastien Villemot wrote:
> But still POWER3 is supported by the 32-bit powerpc port:
> 
>  http://www.debian.org/releases/stable/powerpc/ch02s01.html.en#id522279

Debian powerpc is 32bit, but with 64bit kernel available.  Debian 64bit
powerpc is a new project and not yet anywhere close to a supported port
as far as I know.  Most code probably doesn't benefit from 64bit on
powerpc (it is not like amd64 at all), and would only gain in memory
space for applications by going 64bit to my knowledge.

> My understanding is that POWER3 does not have Altivec, so it may
> therefore be the best option.

Unless of course it has other instructions that the G4 doesn't have.

> Yes, it has to do with the Atlas build system which does CPU detection
> and timings at compile time, and which is quite intricate (to say the
> least).

It looks like they used to have 604e support, which is about as generic
as a powerpc gets (32bit, no altivec, etc).  Someone commented it
out though.

-- 
Len Sorensen