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Date: Tue, 15 Aug 2006 00:38:42 +1000
From: Anton Blanchard <anton@samba.org>
To: =?iso-8859-1?Q?J=F6rn?= Engel <joern@wohnheim.fh-wedel.de>
Subject: Re: [PATCH 1/6] ehea: interface to network stack
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> Is a conditional cheaper than a divide?  In case of a misprediction I
> would assume it to be significantly slower and I don't know the ratio
> of mispredictions for this branch.

A quick scan of the web shows 40 cycles for athlon64 idiv, and its
similarly slow on many other cpus. Even assuming you mispredict every
branch its going to be a win.

Anton