Re: Debian armel/armhf minimal assembly support ?
On Wed, Apr 03, 2013 at 09:59:20PM +0200, Bill Allombert wrote:
> Dear ARM porters,
>
> I like to know what is the minimum CPU level for armel and armhf.
> In particular is support for the following assembly instructions required ?
> umull
> umlal
> clz
>
> The point is whether I should configure a Debian package (pari) to take
> advantage of these instructions.
As far as I remember and understand it:
armel requires ARMv4t or higher instruction set. FPU is optional.
armhf requires ARMv7 or higher instruction set with VFP3-D16 or better
FPU. Neon is not required. armhf is compiled using thumb2 instructions
for the most part as far as I know.
clz is ARMv5t or higher, so armel should not use it. armhf could use
it and should support it.
umull and umlal exist on all ARM versions and should always work.
--
Len Sorensen
Reply to: