Re: [Qemu-devel] Debian 7.8.0 SPARC64 on qemu - anything i can do to speedup the emulation?

[Artyom Tarasenko]

On Mon, Aug 17, 2015 at 5:40 PM, Richard Henderson <address@hidden> wrote:
> On 08/17/2015 07:19 AM, Artyom Tarasenko wrote:
>> Well, on the other hand, every access goes via helper_check_align.
>> There is a comment /* XXX remove alignment check */.
>> I wonder how this can be done in a  more efficient way?
>
> Not ever access does so.  There are only 3 memory related calls to 
> check_align.
>  The other three are for indirect branches.

Yes, but I think it's the 3 most used ones.

> For the 8 byte memory operations we can just remove the checks.  There, the
> softmmu operation checks the alignment.

This is a good news. Where does it happen?

> For usermode, we've typically ignored
> the guest alignment (which also causes failures for a host that requires
> alignment emulating a guest that does not).

Good to know. But I think it's a good compromise between the
performance and accuracy.

Artyom

-- 
Regards,
Artyom Tarasenko

SPARC and PPC PReP under qemu blog: http://tyom.blogspot.com/search/label/qemu