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Date: Thu, 17 Mar 2011 09:06:41 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Oliver Neukum <oneukum@suse.de>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: question oh macros and gcc's intelligence
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References: <201103170848.57688.oneukum@suse.de>
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On Thu, Mar 17, 2011 at 08:48:57AM +0100, Oliver Neukum wrote:
> Hi,
> 
> if I write:
> 
> if (le16_to_cpu(p) == CONST) a();
> 
> is gcc smart enough to convert CONST to le16 and do
> a simple comparison?

On little-endian - certainly, on big-endian - forget it.
	if (p == cpu_to_le16(CONST))
would obviously work on any architecture and yes, it would be a comparison
with compile-time constant.