Date: Fri, 12 Jul 1996 07:43:46 +0800 (GMT) From: Orlando Andico To: "Eric J. Korpela" cc: djgpp AT delorie DOT com Subject: Re: What is the quickiest way to clear memory? In-Reply-To: <4s3ki2$btf@agate.berkeley.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII 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. Hmm.. well I don't program in assembly at all, I'm both lazy and incompetent :) My question is, if anyone's been using gcc-2.7.2p-pl9 (the Pentium optimized GCC) does it do this kind of optimization? I haven't had the time to rebuild (DJGPP) GCC with the Pentium patches, but I *have* built the compiler for Linux and I get a 15% speed increase for the dhrystone2 register benchmark.. if that's significant.. Cheers, Orlando Andico http://gibson.eee.upd.edu.ph/~orly/ orly AT gibson DOT eee DOT upd DOT edu DOT ph "Who knows what's going to happen, IRC Lab/EE Dept/UP Diliman lottery or car crash, or you'll join a cult."