Re: [PATCH] [SPARC] Disable muldf3_extend for LEON/LEON3

[Sebastian Huber <sebastian dot huber at embedded-brains dot de>]

On 25/07/17 14:59, Sebastian Huber wrote:

> On 25/07/17 14:59, Eric Botcazou wrote:
>
> > > Prominent LEON2 chips like the AT697E and AT697F do not properly 
> > > support
> > > the FSMULD instruction.  LEON3 targets using the GRFPU-lite floating
> > > point unit do not support the FSMULD in hardware.  Disable this
> > > instruction for for all LEON/LEON3 targets for simplicity.
> > And penalize everyone else?
>
> Yes, everyone using LEON/LEON3 will no longer benefit from the FSMULD 
> after this patch. This was discussed with Gaisler. We have to make a 
> trade-off between correctness, performance and the number of GCC options.

What is your opinion with respect to a -mno-fsmuld option or something 
similar?

--
Sebastian Huber, embedded brains GmbH

Address : Dornierstr. 4, D-82178 Puchheim, Germany
Phone   : +49 89 189 47 41-16
Fax     : +49 89 189 47 41-09
E-Mail  : sebastian.huber@embedded-brains.de
PGP     : Public key available on request.

Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.