RE: [avr-gcc-list] Inversion of logic improves size speed

[Eric Weddington]

> > -----Original Message-----
> > From:
> > address@hidden
> > [mailto:address@hidden
> > org] On Behalf Of Anatoly Sokolov
> > Sent: Monday, August 27, 2007 7:14 AM
> > To: Wouter van Gulik
> > Cc: address@hidden
> > Subject: Re: [avr-gcc-list] Inversion of logic improves size speed
> >
> >
> > > Anatoly Sokolov wrote:
> > >> Hi.
> > >>
> > >> This patch optimizes logic left shift of unsigned char by
> > 4, 5, and 6,
> > >> excluding double 'andi' instructions in some cases.
> > >>
> >
> > Patch.
> >
> > Anatoly.
>
>
> Hi Anatoly,
>
> I build gcc 4.2.1 with this patch.
>
> Interestingly, for bug #33028 there is no difference between
> 4.1.2, and
> 4.2.1 with this patch. I see the bug show up in 4.3.0
> snapshot, but I have
> not tried the patch with 4.3.x yet.

I've now tried the patch with 4.3.0 snapshot and it does the correct
optimization.

Thanks, Anatoly!

Eric Weddington