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Date:	Tue, 13 Mar 2007 16:57:26 -0700
From:	"Jesse Brandeburg" <jesse.brandeburg@...il.com>
To:	"Arnaldo Carvalho de Melo" <acme@...stprotocols.net>
Cc:	"David Miller" <davem@...emloft.net>,
	"Netdev List" <netdev@...r.kernel.org>
Subject: Re: [PATCH 09/15] [TCP]: Introduce tcp_hdrlen() and tcp_optlen()

On 3/13/07, Jesse Brandeburg <jesse.brandeburg@...il.com> wrote:
> acme, good stuff, but does the " * 4" generate equivalent assembly
> with gcc 3/4 as " << 2" ?
>
> I could assume that the compiler would be smart enough, but every time
> I assume I know what the compiler is doing I get myself in trouble.

nevermind, I wrote a program myself to test it (which I should have
done first).  with x86-64 gcc 3.4.6 or 4.1.0 it always comes out to
shl 2, %eax

etc, sorry for the noise.
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