[Liboil] Is liboil still alive?

[David Schleef]

On Fri, Feb 20, 2009 at 01:26:07PM -0500, Jeff Squyres wrote:
> On Feb 20, 2009, at 11:32 AM, Thiago Galesi wrote:
> 
> >> - Does oil_u8_copy() make non-temporal copies?
> >
> > Ok, AFAIK (and that's what I remember from the docs)
> 
> I re-checked the docs, and they don't say:

Everything in liboil is assumed to be cache-to-cache, so there's
no prefetch and no cache-bypassing writes.  This is a big
limitation for certain users, but unfortunately difficult to
avoid without having 3 versions of each function.  (Actually
more, since there are multiple types of cache bypassing, and
additional combinatorics.) The Orc project will attempt to address
this, if I ever get time to work on it.

> (Open MPI has some assembly code in it, but the main developer of that  
> is gone; it's difficult to maintain now that we no longer have anyone  
> with expertise with assembly)

It's difficult to maintain even when you have years of assembly
experience.

> I do see *some* assembly in liboil/*/*copy*.c.  Does anyone know if  
> any of these have non-temporal copies?  There's no real comments to  
> explain, and I have no idea what the assembly for non-temporal copies  
> looks like...

It would use one of the instructions movntq, movntdq, movntps, or
movnti.



dave...