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From: guy@rlgvax.UUCP (Guy Harris)
Newsgroups: net.lang.c
Subject: Re: String copy idiom.
Message-ID: <587@rlgvax.UUCP>
Date: Thu, 21-Mar-85 00:53:16 EST
Article-I.D.: rlgvax.587
Posted: Thu Mar 21 00:53:16 1985
Date-Received: Fri, 22-Mar-85 02:35:48 EST
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> Beware of saying things like "the fastest possible".
> I found a better way for for any string longer than two characters.
> The following is from 4.2BSD on a VAX.

Geepers, didn't they teach you to use the "-O" option in school?  Running
your example through "cc" with the "-O" flag, I get the same code for
both examples except that the second "FAST" version has an extra test
at the beginning.

"-O" does a fair bit of code motion, especially when strange sequences
of jumps are involved; basically, it's covering PCC's tracks.