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Re: cortex / arm-hardfloat-linux-gnueabi (was Re: armelfp: new architecture name for an armel variant)

> >  One way to check how well softfp performs would be to run povray in
> >  Ubuntu versus in Debian; this will mix noise in the results, but I
> >  don't expect the minor sourceful differences to make the biggest
> >  impact, but rather the toolchain opts would.  (You're speaking of a
> >  3-folds increase.)
> I don't have a debian armel installation here, so I can't test how it
> performs there, however running the same version on a G4@1Ghz running
> squeeze -no altivec- I got total runtime 20 seconds, which is imho
> indicative of the potential performance of the iMX515@800Mhz, as the ARM
> vfp is much less powerful than the G4's. 20 vs 50, sounds almost expected,
> 20s vs ~3min sounds like a joke.

Based on what evidence?

The G4 has an single cycle pipelined out-of-order FPU. The A8 has a 
non-pipelined FPU that takes between 5 and 20 (normal single precision is 10) 
cycles to give a result. A 9x slowdown sounds right on the ball.

Altivec v.s. NEON is a somewhat different question, there's only a 2x 
difference in peak performance there.


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