Performance optimizations for Intel Core 2 and Core i7 processors

[Steven Bosscher]

On Mon, May 17, 2010 at 8:44 AM, Maxim Kuvyrkov <maxim@codesourcery.com> wrote:
> CodeSourcery is working on improving performance for Intel's Core 2 and Core
> i7 families of processors.
>
> CodeSourcery plans to add support for unaligned vector instructions, to
> provide fine-tuned scheduling support and to update instruction selection
> and instruction cost models for Core i7 and Core 2 families of processors.
>
> As usual, CodeSourcery will be contributing its work to GCC.  Currently, our
> target is the end of GCC 4.6 Stage1.
>
> If your favorite benchmark significantly under-performs on Core 2 or Core i7
> CPUs, don't hesitate asking us to take a look at it.

I'd like to ask you to look at ffmpeg (missed core2 vectorization
opportunities), polyhedron (PR34501, like, duh! :-), and Apache
benchmark (-mtune=core2 results in lower scores).

You could check overall effects on an openly available benchmark suite
such as http://www.phoronix-test-suite.com/

Good luck with this project, it'll be great when -mtune=core2 actually
improves performance rather than degrading it!

Ciao!
Steven