By: Gabriele Svelto (gabriele.svelto.delete@this.gmail.com), February 23, 2021 10:15 am
Room: Moderated Discussions
vvid (no.delete@this.thanks.com) on February 23, 2021 6:41 am wrote:
> Anon (no.delete@this.spam.com) on February 23, 2021 3:05 am wrote:
> > anon2 (anon.delete@this.anon.com) on February 22, 2021 7:17 pm wrote:
> > > I don't think memcpy, memset instructions are bad per se, though I still don't understand
> > > the fascination with them, unless their proponents are going to move on to do-daxpy, route-ip-packet,
> > > gzip-memory, etc instructions when/if one day Intel's rep ; mov finally doesn't suck. But
> > > I digress, the point was not a totally open-ended "ISA does not matter".
> >
> > memcpy is quite common, easy to implement in hardware and very inefficient to implement in software.
>
> So easy, that it took Intel literally 4 decades to achieve an acceptable* performance of REP MOVSB.
> * in some situations
Benchmarking memcpy() functions outside of the code they're used in - and without that code interacting with the data - is an exercise in pointlessness.
> Anon (no.delete@this.spam.com) on February 23, 2021 3:05 am wrote:
> > anon2 (anon.delete@this.anon.com) on February 22, 2021 7:17 pm wrote:
> > > I don't think memcpy, memset instructions are bad per se, though I still don't understand
> > > the fascination with them, unless their proponents are going to move on to do-daxpy, route-ip-packet,
> > > gzip-memory, etc instructions when/if one day Intel's rep ; mov finally doesn't suck. But
> > > I digress, the point was not a totally open-ended "ISA does not matter".
> >
> > memcpy is quite common, easy to implement in hardware and very inefficient to implement in software.
>
> So easy, that it took Intel literally 4 decades to achieve an acceptable* performance of REP MOVSB.
> * in some situations
Benchmarking memcpy() functions outside of the code they're used in - and without that code interacting with the data - is an exercise in pointlessness.