From:	"Sly" <sly AT aussie DOT net>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Loop unrolling: Don't bother
Date:	2 Mar 1997 03:02:36 GMT
Organization:	Sly
Lines:	21
Message-ID:	<01bc26b6$baa04420$87081ecb@sly>
References:	<5f5knj$cho AT freenet-news DOT carleton DOT ca><01bc252e$b1edb440$82081ecb AT sly> <5f8vsu$g84 AT flex DOT uunet DOT pipex DOT com>
NNTP-Posting-Host:	max0ppp05.bne.aussie.net
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

nikki <nikki AT gameboutique DOT co> wrote in article
<5f8vsu$g84 AT flex DOT uunet DOT pipex DOT com>...
> > Is it possible that with the -O3 option, the compiler sees that these
are
> > indeed constant iteration loops, and unrolls them itself?  Try it with
-O0
> > option, because this should turn off all optimisation.  -O3 is the
highest
> > level of optimisation available.
> 
> i'm fairly sure o3 doesn't unroll loops, or at least it's never unrolled
any
> of mine ;) you can also use o4 no? at least i thought you could..
> 

O4 option?  Does that exist?  The GCC Info docs only go up to O3, with some
extra optimization options available, but no O4.

-- 
TTFN
Sly (Steve)

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