Date: Mon, 18 Feb 2008 18:40:27 -0800
From: Arjan van de Ven <arjan@infradead.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Andi Kleen <andi@firstfloor.org>, Willy Tarreau <w@1wt.eu>,
       Roel Kluin <12o3l@tiscali.nl>, geoffrey.levand@am.sony.com,
       linuxppc-dev@ozlabs.org, cbe-oss-dev@ozlabs.org,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/3] Fix Unlikely(x) == y
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On Tue, 19 Feb 2008 13:33:53 +1100
Nick Piggin <nickpiggin@yahoo.com.au> wrote:
> 
> Actually one thing I don't like about gcc is that I think it still
> emits cmovs for likely/unlikely branches, which is silly (the gcc
> developers seem to be in love with that instruction). If that goes
> away, then branch hints may be even better.

only for -Os and only if the result is smaller afaik.
(cmov tends to be a performance loss most of the time so for -O2 and such it
isn't used as far as I know.. it does make for nice small code however ;-)

 
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