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Date: Fri, 24 May 2002 19:00:12 +0100
From: Christoph Hellwig <hch@infradead.org>
To: Robert Love <rml@tech9.net>
Cc: Marcus Meissner <mm@ns.caldera.de>, linux-kernel@vger.kernel.org
Subject: Re: Compiling 2.2.19 with -O3 flag
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On Fri, May 24, 2002 at 10:55:20AM -0700, Robert Love wrote:
> I know this...maybe I am not being clear.  I realize -Os is a derivate
> of -O2, but is it not an interesting note if -Os can be as fast (or
> faster) than -O2 and still generate smaller binaries?  That is my point.

I've seen it beeing faster with gcc 2.95.  Alan's point was (and I think
the explanation is plausible) is that it is faster exactly _because_ it
produces smaller code due to the instruction cache behaviour of many
current CPUs.