Re: CVS commit: src/sys/arch/arm/arm

[David Laight <david%l8s.co.uk@localhost>]

On Sun, Dec 23, 2012 at 01:26:21PM +0000, Matt Thomas wrote:
> Module Name:  src
> Committed By: matt
> Date:         Sun Dec 23 13:26:21 UTC 2012
> 
> Modified Files:
>       src/sys/arch/arm/arm: cpu_in_cksum_fold.S
> 
> Log Message:
> Conditional execution still takes one cycle per skipped instruction.
> branch to unlikely cases instead of conditionally skipping them.

Or more for 'ldm' and 'stm' - esp. I think on strongarm!

Conditional execution might also be a full pipeline stall, rather
than a branch which is likely (hopefully) to be predicted correctly.

        David

-- 
David Laight: david%l8s.co.uk@localhost