Re: [RFC] Contributing tree-ssa to mainline

[Roger Sayle <roger@eyesopen.com>]

On Sat, 17 Jan 2004, Jan Hubicka wrote:
> > My greatest disappointment working on GCC's optimizations, is that
> > try as I might I've only ever been able to push Andreas' SPECcpu2000
> > benchmarks perhaps a percentage point or two higher.  This on a platform
> > where Microsoft's compilers score about 20% higher.  Intel similarly
> > claims about 20% better performance than GCC on average.
>
> How did you got to this number?
> This is definitly not the case of SPECint scpres I saw.  My experience
> is that we are about 2-3% behind AMD published results in 32bit mode.

The published figures are on Andreas' site for the world to see.
http://www.suse.de/~aj/SPEC/

If you click on "SPECint2000 results (permanent runs, non-reportable)"
you get mainline's current performance, which from the graph at the
bottom is just about 400 as of January 17th 2004.

If you then go to the section entitled "Comparisons with Other Compilers"
and click on the "SPECint200 in 1.2GHZ AMD Athlon", which is described
as "these results should give an indication of how good/bad GCC is",
you'll see a SPEC report with SPECint2000 of 496.  And that was with
the Intel 5.0 compiler!

The difference between 400 and 500 is about 20%.


Perhaps you could provide details of where you 2 or 3% comes from?

Roger
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