arch-specific directories

[Marcel Moolenaar]

On Jun 14, 2010, at 9:51 AM, John Baldwin wrote:
> 
> I think for archs that share a lot in common between 32-bit and 64-bit 
> varieties using shared sources of some sort (e.g. sys/x86) should be 
> encouraged.  This is probably more true (and feasible) for more recently added 
> architectures such as powerpc, arm, and mips.  Alpha and ia64 would not have 
> fit into this category.

ia64 has both a 32-bit runtime as well as a 64-bit runtime defined.
Only HP-UX exploits the 32-bit runtime, because it eased porting
from PA-RISC to IA-64 without the 64-bit issue. We don't implement
the ILP32 runtime, but the feasibility is still there. This puts
ia64 in the same bucket as powerpc, arm and mips.

Also note that ia64 supports both big-endian and little-endian.
While we only support little-endian at this time, there's still
the feasibility for big-endian. This puts ia64 in the same bucket
as arm and mips.

-- 
Marcel Moolenaar
xcllnt at mac.com