[maemo-developers] Performance of floating point instructions

[From: Ove Kaaven]

Alberto Mardegan skrev:
> Does anyone know any tricks to optimize certain operations on arrays of
> data?

The answer to that is, obviously, to use the Cortex-A-series SIMD
engine, NEON.

Supposedly you may be able to make gcc generate NEON instructions with
-mfpu=neon -ffast-math -ftree-vectorize (and perhaps -mfloat-abi=softfp,
but that's the default in the Fremantle SDK anyway), but it's still not
very good at it, so writing the asm by hand is still better... and I'm
not sure if it can automatically vectorize library calls like sqrt.