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From: Andreas Schwab <schwab@suse.de>
To: Joseph Myers <joseph@codesourcery.com>
Cc: <pinskia@gmail.com>,  Wilco Dijkstra <wdijkstr@arm.com>,  GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] Use strlen when searching for a nul char
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	<alpine.DEB.2.10.1510071505450.29388@digraph.polyomino.org.uk>
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Date: Wed, 07 Oct 2015 15:30:00 -0000
In-Reply-To: <alpine.DEB.2.10.1510071505450.29388@digraph.polyomino.org.uk>
	(Joseph Myers's message of "Wed, 7 Oct 2015 15:20:31 +0000")
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Joseph Myers <joseph@codesourcery.com> writes:

> (And please accompany performance claims such as "faster on most targets" 
> with figures from the benchtests or a reason it's hard to produce such 
> figures.  In this case I think the transformation could be justified for 
> GCC as something architecture-independent without specific performance 
> claims - strlen being inherently simpler because it only ever has to 
> search for 0 bytes, so it should never be asymptotically slower than the 
> alternative and may be faster.)

On the debit side you have to keep the value of the pointer around in
order to add it afterwards.

Andreas.

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Andreas Schwab, SUSE Labs, schwab@suse.de
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