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Date: Thu, 2 Nov 2000 11:37:26 -0800
From: Richard Henderson <rth@twiddle.net>
To: Martin Dalecki <dalecki@evision-ventures.com>
Cc: tytso@mit.edu, Jakub Jelinek <jakub@redhat.com>,
        Horst von Brand <vonbrand@sleipnir.valparaiso.cl>,
        linux-kernel@vger.kernel.org
Subject: Re: 2.4.0-test10-pre6: Use of abs()
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On Thu, Nov 02, 2000 at 01:14:49PM +0100, Martin Dalecki wrote:
> However what's the difference in respect of optimization between
> unrolling the abs function by hand and relying on the built in?

Should be nothing.  The expanded source expression should get
folded immediately to an ABS_EXPR node, at which point you are
at exactly the same point as the builtin would have gotten you.


r~
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