From: Andi Kleen <[email protected]>
Date: 27 Aug 2005 04:34:07 +0200
> "David S. Miller" <[email protected]> writes:
>
> > From: Alexey Dobriyan <[email protected]>
> > Date: Sat, 27 Aug 2005 02:58:48 +0400
> >
> > > What's the point of having unlikely() attached to every possible if ()?
> >
> > If can result in smaller code, for one thing, even if it
> > isn't a performance critical path.
>
> Really? At least on x86 it tends to generate bigger code when
> block reordering is enabled because a jump forward and a jump
> backward and a possible label alignment are bigger than just
> a single jump forward.
In the cases I've studied on sparc64 it keeps gcc from doing basic
block replication in the unlikely paths.
I've only checked gcc-3.4 and earlier, gcc-4.x is just big bloated
useless garbage and should be avoided for a couple of years.
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