RE: [Squeak-VMdev] global struct for Acorn makes 30% speedup :-)

[Tim R. <ti...@su...>]

In message <001e01c27037$1b539590$f7affea9@Atlantis>
          "Andreas Raab" <And...@gm...> wrote:

> Interesting. BTW, the reason why it doesn't work well with Intel is that
> Intel has all sorts of global addressing modes built into the
> instructions, meaning there's no extra indirection required for
> accessing globals and that "wasting" that extra register for holding the
> ref to the global structure will work heavily against you.
Exactly. It's going to make it fun working out a way to use it on unix
machines with suitable CPUs. Windows/Acorn/OS-X are easy since they're
one OS/one cpu type. I guess wince counts as well these days since it's
ARM only. But *nix is everything!

The key for better performance on the Acorn was the use of the global
register trick. GCC has the same ability buried in there somewhere.

tim

-- 
Tim Rowledge, ti...@su..., http://sumeru.stanford.edu/tim
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