Bug#724320: gmp: x32: sizeof(mp_limb_t)!=sizeof(void*) is not supported by GAP and PARI

Vincent Lefevre vincent at vinc17.net
Sat Sep 28 21:40:07 CEST 2013


On 2013-09-28 10:38:24 -0500, Steve M. Robbins wrote:
> Hi,
> 
> On September 28, 2013 10:26:33 AM Vincent Lefevre wrote:
> > On 2013-09-28 09:03:53 +0200, Marc Glisse wrote:
> 
> > > the whole point of creating x32 was to benefit from the speed advantages
> > > of amd64 without having a pointer size of 64 bits. Those speed advantages
> > > include using more registers, but also using hardware 64 bit long long.
> > > The speed difference between 32 and 64 bits [ ... ] so it doesn't make
> > > sense to me to penalize x32
> >
> > I agree. PARI is not the only software that uses GMP.
> 
> OK, so I may not have been completely clear, but what I was asking is which 
> makes most sense for Debian's GMP package: 8 bytes or 4 bytes.  I think what 
> Marc and Vincent are saying is that 8 bytes is the better choice.  Did I read 
> that correctly?

Yes, I think that 8 bytes is the better choice if this leads to
faster code and doesn't break other software than PARI.

-- 
Vincent Lefèvre <vincent at vinc17.net> - Web: <http://www.vinc17.net/>
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