Thinking a bit more, I think the VFP emulation for older hardware could
be a viable option to have all the packages compiled with -mfpu=vfp. I
can't estimate the performance difference between softfloat and VFP
emulation but, if the performance on Xscale is visibly affected, we
still have the option of two builds of glibc (and other libraries) where
the default one is VFP and the additional one is softfloat. Since
-mfloat-abi=softfp, mixing VFP and softfloat packages is still possible.

As I said, all the VFP floating point operations are already implemented
in the kernel. There are around 20 additional instructions (actually
variants of a fewer number) for transferring data between VFP registers
and memory or ARM registers which aren't handled plus the VFP register
bank to be accessed from memory rather than the coprocessor registers.
As a rough estimate, I think it would take me around 2 weeks to get this
done.

Does this sound feasible? Thanks.

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armel gcc default optimisations
https://bugs.launchpad.net/bugs/303232
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