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Date: Mon, 14 Apr 2003 22:02:16 +0100
From: Dave Jones <davej@codemonkey.org.uk>
To: Duncan Sands <baldrick@wanadoo.fr>
Cc: "Martin J. Bligh" <mbligh@aracnet.com>, Andrew Morton <akpm@digeo.com>,
       linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: BUGed to death
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On Mon, Apr 14, 2003 at 10:40:41PM +0200, Duncan Sands wrote:

 > You would think that the compiler would consider a branch leading to
 > ud2 (i.e. BUG()) to be "unlikely", but it doesn't seem to.  Maybe some
 > improvement can be made there.

BUG_ON is already marked unlikely.
See include/linux/kernel.h

The costs here are doing the actual checks, nothing to do with
the branch prediction.

		Dave