Re: [Cbe-oss-dev] [PATCH 1/3] Fix Unlikely(x) == y

From: Andrew Pinski
Date: Mon Feb 18 2008 - 14:22:31 EST


On Feb 18, 2008 6:01 AM, Geert Uytterhoeven
<Geert.Uytterhoeven@xxxxxxxxxxx> wrote:
> > This means it generates faster code with a current gcc for your platform.
> >
> > But a future gcc might e.g. replace the whole loop with a division
> > (gcc SVN head (that will soon become gcc 4.3) already does
> > transformations like replacing loops with divisions [1]).

Yes but the issue is one optimization inside GCC does not take into
account the probability in one case.

And really there is a bug in the linux kernel for not implementing the
long long divide function (or really using libgcc) but that is a
different story and is part of the issue there anyways.

-- Pinski
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