[fedora-arm] armv7hl requirements

[Chris Tyler]

On Wed, 2011-05-04 at 14:46 -0400, Jon Masters wrote:
> I think we should build for ARM (as opposed to Thumb2) but we should
> support interworking with Thumb2 code through the toolchain options. We
> should then later consider implementing some Thumb2 optimization. It's
> more armv7thl, but the (t) is implied since it's ARMv7 anyway.

The thumb2 situation needs a bit more investigation. I had someone do
tests on thumb vs non-thumb last year, and there was no question about
thumb1 on v5 (thumb caused a major performance hit) but it was not
nearly as clear for thumb2 on v7 - the (very preliminary) results (using
a BeagleBoard) indicated the same or slightly better performance for
thumb2 over non-thumb2 (this was for packages built using the rpm/mock
toolchain with what were otherwise normal Fedora flags), and obviously a
smaller binary size. I think some comprehensive testing is needed.

-Chris