GCC - Optimal Optimization

[Sean M.]

--- Oliver Fromme <olli at lurza.secnetix.de> wrote:
> The default is "-O2 -fno-strict-aliasing -pipe".

info gcc --index "optimize options" says the default is '-O0'.

> You said you don't want an increase in size.  But that's
> exactly what -O3 (via inlining) and -funroll-loops do.
> If you want not to increase size, use the default flags.
> You could even use -Os, which instructs the compiler to
> optimize for small size (it's somewhere between -O and
> -O2).

"-O3" was a typo, I meant "-O2". And I'm not against an absolute
increase in size, just a significant one (>10% is about where I'd start
to care)

--- Nikolas Britton <nikolas.britton at gmail.com> wrote:
> IIRC the Duron should be set to athlon or athlon-tbird. The athlon-4,
> athlon-xp, athlon-mp knobs should only be used on Athlons with a
> Palomino core or better, your Duron is to slow to be based off
> Palomino. Also -mfp-math=sse does nothing for you because your chip
> doesn't have full SSE support.

No, athlon-xp is valid:
"The second-generation Duron, the "Morgan" core, was sold in speed
grades between 900 and 1300 MHz, and was based on the 180 nm "Palomino"
Athlon XP core." [wikipedia.org]

And -mfp-math=sse actually does nothing because there's not supposed to
be a hyphen between "fp" and "math".

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com