Re: [PATCH] i386: optimize memset of 6 and 8 bytes

From: Arjan van de Ven
Date: Fri Aug 17 2007 - 22:01:27 EST



On Fri, 2007-08-17 at 18:54 -0700, Stephen Hemminger wrote:
> On Fri, 17 Aug 2007 18:49:34 -0700
> Arjan van de Ven <arjan@xxxxxxxxxxxxx> wrote:
>
> >
> > On Fri, 2007-08-17 at 16:50 -0700, Stephen Hemminger wrote:
> > > Tne network code does memset for 6 and 8 byte values, that can easily
> > > be optimized into simple assignments without string instructions.
> >
> >
> > so... question.
> > Why are we doing this by hand? Wouldn't gcc just generate this code in
> > the first place (when using __builtin_memset)? I very much suspect it
> > would (and if some version doesn't.... we really ought to get that
> > fixed)
>
> i386 and x86_64 are not using __builtin_memset, as least from the
> code that I see generated.

.. maybe we should just fix it that way then?

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