Xref:	news2.mv.net comp.os.msdos.djgpp:6022
From:	Arash <ei39594 AT ios DOT chalmers DOT se>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: What is the quickiest way to clear memory?
Date:	15 Jul 1996 16:00:07 GMT
Organization:	Chalmers University of Technology
Lines:	31
Message-ID:	<4sdpu7$of6@nyheter.chalmers.se>
References:	<Pine DOT SGI DOT 3 DOT 93 DOT 960712074101 DOT 1646D-100000 AT gibson DOT eee DOT upd DOT edu DOT ph>
NNTP-Posting-Host:	sv31975.ios.chalmers.se
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

-- Orlando Andico <orly AT gibson DOT eee DOT upd DOT edu DOT ph> wrote:
>On 11 Jul 1996, Eric J. Korpela wrote:
>> Unless you're not using a 386.  On pentium the fastest method seems
>> to be an unrolled loop of fistq. (64 bits at a time)  On 486 machines
>> that are clock doubled or tripled, an unrolled loop of movl instructions
>> seems to be fastest.  rep stosd is only fastest on 386 and non-multiplied
>> 486 machines.

i THINK the best way is something like
  memset((void *) 0xa0000 + __djgpp_conventional_base,0,64000);
could do the trick. (I don't know if nearptr is faster than farptr)
You have fixed size -> rep movl (not movb!!), and -m486 -O2 
-funroll-loops -> unrolles loops just to fit in chache and no more!

Any way if this is wrong, I have to totaly rewrite my game :(




-Arash
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