Re: Preparation for creating netbsd-7 branch

[Matt Thomas <matt%3am-software.com@localhost>]

On Jul 21, 2014, at 12:50 PM, Manuel Bouyer <bouyer%antioche.eu.org@localhost> 
wrote:

> On Sun, Jul 20, 2014 at 08:45:40PM -0700, Matt Thomas wrote:
>> [...]
>> 
>> Absolutely.  You can't run an earmv7 on earmv6 or before.  You default to 
>> just earm but you lose efficiency and performance.  An earmv7hf userland is 
>> much faster on an armv7 cpu than a earm{,hf} userland.  
> 
> 
> I tested earmhf vs earmv7hf on the beaglebone black. with glxgears,
> the performance improvement is less than 1%.
> 
> Do you have other tests that show a large gain with earmv7hf vs earmhf ?
> For 1% I don't think we should bother providing all of
> earmhf, earmv6hf and earmv7hf.

Try string processing, armv6+ have much faster support for the str* routines.
Also, I've been working on faster memcpy taking advantage of the hardware
fixed of unaligned accesses.