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Mail Archives: djgpp/1998/08/22/22:58:53

Message-ID: <35DF7145.69CE8229@unb.ca>
Date: Sat, 22 Aug 1998 22:32:53 -0300
From: Endlisnis <s257m AT unb DOT ca>
MIME-Version: 1.0
To: Nate Eldredge <nate AT cartsys DOT com>
CC: djgpp AT delorie DOT com
Subject: Re: Inline asm
References: <199808010337 DOT EAA08924 AT sable DOT ox DOT ac DOT uk> <35C29036 DOT ADF11F19 AT access DOT net DOT au> <35D253DA DOT B04B8D98 AT unb DOT ca> <35DF1418 DOT 402230C2 AT cartsys DOT com>

Nate Eldredge wrote:

> >     No, memcpy (no 'o') copy's 4-byte chunks (but also works with blocks not
> > divisible by 4).  There is a function memmove that copies 1 byte at a time
> > in case the regions overlap, but it is (essentially) 4 times slower.
>
> You are thinking of `memmove', but it also uses 4-byte transfers.

    I did say 'memmove' on line#3 of the quoted text above.

> (Think about it-- 1 byte at a time wouldn't help the case of overlapping
> areas.)  What it does is copy backwards if necessary.  I think the
> reason it's slower (if indeed it is) is because it's written in C rather
> than assembly (this is from memory and may be totally wrong).  AFAIK,
> this will change with 2.02

    memmove is a least 2 to 4 times slower.

--
     (\/) Endlisnis (\/)
          s257m AT unb DOT ca
          Endlisnis AT GeoCities DOT com
          Endlis AT nbnet DOT nb DOT ca




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