Re: [MiNT] Why not O3

[François LE COAT <lecoat@ief.u-psud.fr>]

Hi,

Konrad M. Kokoszkiewicz wrote:

> Die 30.03.01 (20:09) owner-mint@fishpool.com scripsit:
> > Question: why Mint kernel is compiled with O2 and not 03? 
> Because -O3 is the same as -O2 -funroll-loops, IIRC, which produces larger
> binaries not gaining any significant speedup.

You should compile -O1, that is, as far as I know, optimisation
for space (executable size). There is a paradox : I found that
-O1 compilations are faster than -O3. I made my opinion on that.
In facts, Atari machines have very tiny cache memory, and there's
no L2 caches. So, optimisations for speed (-O3) that generate
supposed faster code, by the way of unrolling loops and others
expensive optimisations etc ... are not efficient on our
platforms. The compacity of executable's code is much more
efficient. Try it, you'll see.

Bye for now,

Regards,

Dr François LE COAT
http://eureka.atari.org
mailto:lecoat@atari.org