Re: C++: EGCS perf. vs GCC

[Alex Maranda <amaranda at spider dot com>]

> 
>   In message <Pine.GSO.3.96.981207132218.2689A-100000@caleyipa.spider.com>you w
> rite:
>   > 3. Compilers used
>   > 
>   > gcc 2.8.1
>   > egcs 1.1b (yes, I know 1.1.1 is out)
> I doubt egcs-1.1.1 would make any signficant difference performance-wise.  If
> it did, it would be by accident, not by design.
I've just downloaded 1.1.1; I'll have fresh figures in a couple of days.

> 
>   > i486 code, but other than that, the results are a complete surprise for me.
>   > I've expected that the proper use of the PII pipeline, etc. would boost the
>   > figures at least by 10%, and not degrade the performance!
> The scheduling for all x86 ports is poor at best.  It needs to be completely
> revamped from the ground up.
Hmm, I have not used on the Intel architecture other compilers than gcc,
but I trust your judgement; I am thrilled with the PII performance vs.
Ultra SPARC II performance for example (ok, I'm not fair here, the Ultra
processor was running at 248 Mhz), the part which I don't understand is
why -mcpu=pentiumpro is worse than -mcpu=i386 on a PII, and why gcc2.8.1
generates better code for i386 than egcs1.1.
I understand there is a Pentium compiler around (pcc or something); will
it do any difference? (or this is the stuff on which the Pentium support
in gcc/egcs is based?)
And finally, is Pentium II = Pentium Pro+MMX+better L2 cache? this why I
hoped -mcpu=pentiumpro will unleash the demons living in my machine :-)

PS: I will try the flags suggested by Gerhard Heinzel on both gcc2.8.1 and
egcs1.1.1 and strike again with an updated report :-)

Cheers,
Alex