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Date: Sun, 6 Jan 2002 05:19:11 +0100 (CET)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: <mingo@elte.hu>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>,
        Linus Torvalds <torvalds@transmeta.com>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [announce] [patch] ultra-scalable O(1) SMP and UP scheduler
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On Sun, 6 Jan 2002, Alan Cox wrote:

> There are better algorithms than the branching one already. You can do
> it a 32bit one with a multiply shift and 6 bit lookup if your multiply
> is ok, or for non superscalar processors using shift and adds.
>
> 64bit is 32bit ffz(x.low|x.high) and a single bit test

ok - i wasnt thinking straight. as few branches as possible should be the
way to go, no BTB will help such functions so branches must be reduced.

	Ingo

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