[LLVMdev] FYI: Phoronix GCC vs. LLVM-GCC benchmarks

Török Edwin
2009-09-18T07:59:09Z

On 2009-09-16 17:32, Olivier Meurant wrote:
>
>
> On Wed, Sep 16, 2009 at 3:46 PM, Stefano Delli Ponti
> <stefano.delliponti at gmail.com <mailto:stefano.delliponti at
gmail.com>>
> wrote:
>
>     I don't know what you think about this, but shouldn't it be
more
>     meaningful to make these tests with -O3? I mean, we ought to make the
>     comparisons with the highest level of optimization available for
>     both of
>     the compilers. It is difficult to compare an intermediate level.
>
>
>
> A quick test confirms that the 40% difference stays even with an -O3
> switch on both compilers.
> I just "choose" -O2 as it's the default of the original
makefile.

It would be interesting to see if LLVM has improved since 2.5 on this
benchmark, could you try the prerelease here?
http://llvm.org/prereleases/2.6/

A 40% performance loss is bad, something should be done about it for
LLVM 2.7 (if it is too late for 2.6 already).

Best regards,
--Edwin