From: Kenneth Hoste <kenneth.hoste@ugent.be>
To: Martin Guy <martinwguy@gmail.com>
Cc: ami_stuff <ami_stuff@o2.pl>, gcc@gcc.gnu.org
Subject: Re: GCC 4..4.x speed regression - help?
Date: Mon, 17 Aug 2009 08:53:00 -0000 [thread overview]
Message-ID: <E8DE22EF-5BAF-4093-B997-2283810A9BAE@ugent.be> (raw)
In-Reply-To: <56d259a00908160902q54cda0a6nab0d7eb28abd8d48@mail.gmail.com>
On Aug 16, 2009, at 18:02 , Martin Guy wrote:
> Yes, GCC is bigger and slower and for several architectures generates
> bigger, slower code with every release, though saying so won't make
> you very popular on this list! :)
>
> One theory is that there are now so many different optimization passes
> (and, worse, clever case-specific hacks hidden in the backends) that
> the interaction between the lot of them is now chaotic. Selecting
> optimization flags by hand is no longer humanly possible.
That, and the fact that GCC supports so many (quite different) targets
while keeping the set of optimization passes roughly equal across
these targets probably also doesn't help...
I'm aware there are (good) reasons to try and keep it that way, but it
seems
the reasons against it are getting stronger.
Just my 2 cents.
Kenneth
PS: There's MILEPOST, but there are other projects too. Check out Acovea
(http://www.coyotegulch.com/products/acovea) and my very own
pet COLE (http://users.elis.ugent.be/~kehoste/, see the publications
section).
--
Kenneth Hoste
Paris research group - ELIS - Ghent University, Belgium
email: kenneth.hoste@elis.ugent.be
website: http://www.elis.ugent.be/~kehoste
blog: http://boegel.kejo.be
next prev parent reply other threads:[~2009-08-17 7:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-08-16 16:02 ami_stuff
2009-08-16 22:46 ` Bernd Roesch
2009-08-17 0:39 ` ami_stuff
2009-08-17 6:42 ` Martin Guy
2009-08-17 8:53 ` Kenneth Hoste [this message]
2009-08-17 10:00 ` Richard Guenther
2009-08-17 9:03 ` Paolo Bonzini
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