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Date: Fri, 2 May 2003 06:04:53 -0400
From: Chuck Ebbert <76306.1226@compuserve.com>
Subject: Re: [RFC][PATCH] Faster generic_fls
To: Peter Osterlund <petero2@telia.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
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Peter Osterlund wrote:

>>   mov <mem1>,eax
>>   mov eax,<mem2>
>>   mov <mem1>,eax        ; eax already contains mem1 you stupid compiler
>>   ret
>
> Not necessarily if mem2 == mem1 + 2. Consider this code:

  I realized after sending that last that I should have added that there
were no volatiles and no aliasing possible.  This was the kernel code:

  return conf->last_used = new_disk;

(new_disk is a local variable, conf is a function arg.)

------
 Chuck
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