On Wed, May 04, 2011 at 01:46:06PM -0500, Jon Masters wrote:
Folks,
I'd like to kick off a discussion about flags for ARMv7. My proposal
here is that we treat v7hl as an entirely different architecture, and
don't try any multi-arch kind of hacks (there isn't the established user
base for Fedora ARM to justify doing any of those things at the moment).
Things I think we should consider as a minimum:
*). Little endian (obviously, but worth stating) (l)
*). Cortex-A8 or higher fully compliant core(s)
Is there a measureable difference in code optimized for A8 vs A9 when
running on A9? If so, my inclination would be to build for the future
- A9. It's not like A9 hardware is hard to come by these days.
*). ARM VFP3 hardware floating point (h)
*). ARM NEON Architecture
If libraries using NEON can detect NEON-capable CPUs and switch to
using those functions, all the better. Unfortunately, not all
A9 products include NEON, but then again, not all apps can make use of
NEON SIMD instructions anyhow.
--
Matt Domsch
Technology Strategist
Dell | Office of the CTO