From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: The type of bitops
Date: Mon, 06 May 2013 18:36:32 -0700
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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch <linux-arch@vger.kernel.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>

On 05/06/2013 05:51 PM, Linus Torvalds wrote:
> 
>> 4. Do some macro hacks so the bitops are dependent on the size of the
>>    argument.
> 
> That sounds insane. Just *how* could the size of the argument even
> matter? Seriously, there's no *difference* between a 32-bit or a
> 64-bit index. The code is the same, there's no possible reason to make
> it be different.
> 

The only reason on x86 would be to avoid the REX prefix.  Hardly worth
it, though.

	-hpa