From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [PATCH] - trivial - Improve appletalk checksum calculation
Date: Mon, 22 Oct 2007 20:39:59 -0700
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	 <20071022203052.23725719@freepuppy.rosehill>
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Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
	netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>
To: Stephen Hemminger <shemminger@linux-foundation.org>
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On Mon, 2007-10-22 at 20:30 -0700, Stephen Hemminger wrote:
> > Corrected fast code is:
> > 
> >         while (len--) {
> >                 sum += *data++;
> >                 sum <<= 1;
> >                 sum = (((sum & 0x10000) >> 16) + sum) & 0xffff;
> >         }
> > 
> > At least it is correct on the standalone random data test, and the
> > new code is 30% faster for the cached memory case (13.7 clks/byte vs 18 
> > clks/byte).
> Your code looks different...

Both are 16 bit rotate lefts.
Which looks clearer?