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From: robert@sri-spam.UUCP
Newsgroups: comp.arch,comp.lang.c
Subject: Re: String Handling -- Incompetence of run-time libraries
Message-ID: <9996@sri-spam.istc.sri.com>
Date: Wed, 1-Apr-87 11:58:19 EST
Article-I.D.: sri-spam.9996
Posted: Wed Apr  1 11:58:19 1987
Date-Received: Sat, 4-Apr-87 07:13:47 EST
References: <15292@amdcad.UUCP> <978@ames.UUCP> <15694@sun.uucp>
Reply-To: robert@sri-spam.UUCP (Robert Allen)
Organization: SRI International, Menlo Park
Lines: 40
Keywords: instruction set architectures, strcpy
Xref: utgpu comp.arch:743 comp.lang.c:1417

In article <1359@steinmetz.steinmetz.UUCP> davidsen@kbsvax.steinmetz.UUCP (William E. Davidsen Jr) writes:
>$In article <1944@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) pointed out
>$that printf could be recoded to run much faster.
>...
>$strcpy2(ss1,ss2)
>$char *ss1,*ss2;<---------------------------- put "register" on this line
>${	register char *s1,*s2;<-------------- as many compilers will use this
>$					      as local variables overriding
>$	s1 = ss1;			      the arguments.
>$	s2 = ss2;
>$	while (*s1++ = *s2++);	}
>
>I'm going to try these on some of the machines I use, and see if this
>will speed up things.

To further speed this up you could write it as:

	strcpy2(ss1,ss2)
	register char *ss1, *ss2;
	{
	    while (*s1++ = *s2++)
	    ;
	}

thus eliminating two assignments and two local variables.

-- 
---------------------------------------------------------
    Glover (upon discovering that Gibson is his new partner):
	"God hates me, that's what the problem is!"

    Gibson (blowing cigarette smoke out his nose):
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	"PUNTA, PUNTA, PUNTA!!"

Robert Allen,
robert@spam.istc.sri.com
---------------------------------------------------------