Re: [Qemu-devel] Performances on Mac OS X

[Falk Hueffner <hueffner@informatik.uni-tuebingen.de>]

Laurent Amon <amon@stanfordalumni.org> writes:

> Just to let you know that I have been benchmarking with linux-test/nbench on my
> Titanium G4/400 and that I have been able to sqeeze a few percents (some 5%) of
> performance by compiling with -mcpu=7400 wirth GCC 3.3. This is the only flag
> that seems useful.
> I have also tried -mpowerpc-gpopt, -mpowerpc-gfxopt, -falign-loops,
> -funroll-loops, -fnew-ra, -ftracer.

Well, the instruction stubs don't contain loops and are short enough
to be trivial to assign registers. So this is not really surprising.

> I was wondering whether the implementation of qemu is tied to gcc or
> if it might be interesting to try to compile using IBM's compiler,
> which is able to generate Altivec code...

It might be possible with some work, but Altivec will not be useful
for the vast majority of instructions, basically only for MMX and
similar things, which AFAIK aren't yet supported in qemu.

-- 
	Falk