'bx lr' vs 'mov pc,lr'

[Felipe Contreras]

On Mon, Sep 14, 2009 at 1:58 AM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Mon, Sep 14, 2009 at 12:55:24AM +0300, Felipe Contreras wrote:
>> I noticed that in 'arch/arm/lib/delay.S' we are using 'mov pc, lr'
>> instead of 'bx lr'. Why? It looks like 'mov pc, lr' is used all over
>> the place, but I can't find out what's the reason.
>
> Why do you want bx?  bx isn't available on older CPUs.

Isn't it faster? I don't know if it would make sense to try it on newer CPUs.

-- 
Felipe Contreras