Subject: Re: VAX instructions (Was: VAX VECTOR chip, what part number?)
To: David Brownlee <abs@netbsd.org>
From: Gunther Schadow <gunther@aurora.regenstrief.org>
List: port-vax
Date: 05/24/2001 15:01:05
David Brownlee wrote:

> > >     Are there any compile time options to control the use of them?

> > gcc don't use them, and I don't know if there would be of any use to
> > learn gcc about them.

Well, take the bit field instructions for example, they would be
very useful for gcc to know when dealing with bit fields: otherwise
it's just gonna be more work with and / shift right and shift left / or
respectively.
 
> >                      If something should be done then I think that
> > it would be two different libc's and do something like the x86 libm
> > changing.
> 
>         That would be assembler stubs for appropriate routines?

right, with some smart way of falling back to the spelled out
version if the feature isn't available on the currently running
processor.

However, this is certainly not highest priority. Would be a nice
job for someone who doesn't quite like to do kernel hacking. But
as of yet, kernel hacking (SMP!!!) is far more important.

-Gunther

-- 
Gunther Schadow, M.D., Ph.D.                    gschadow@regenstrief.org
Medical Information Scientist      Regenstrief Institute for Health Care
Adjunct Assistent Professor        Indiana University School of Medicine
tel:1(317)630-7960                         http://aurora.regenstrief.org