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Re: GCC 4..4.x speed regression - help?



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


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