Hi Jonas,
On 04/09/2014 11:11 AM, Jonas Gorski wrote:
On Wed, Apr 9, 2014 at 10:55 AM, Markos Chandras
<Markos.Chandras@xxxxxxxxxx> wrote:
I used in fact only R2 devices. I also use R2 specific instructions such as
"ins" and "wsbh". I haven't really considered supporting older ISAs for a
couple of reasons. R2 has been around for a long time so a ~7y old device is
probably R2 capable. Furthermore, I was not sure whether mips32/64R1 devices
are likely to run the latest kernel (and/or use BPF-JIT at all). But I could
easily be wrong.
Having said that, it's possible to support R1 devices but I'd like to avoid
the overhead so a few #ifdefs are needed in the code. My personal preference
is to support R2 in the initial patch, and add R1 support later on (along
with the optimizations I have in mind).
As far as I can tell on a first glance, you are only using "wsbh", and
only if the device is running little endian. There is code to emit
"ins", but it isn't evoked from anywhere.
You are right. Seems like a leftover while I was playing with different
implementations. I will drop it. Regarding the wsbh, I assume a few ORs
and shifts will emulate the wsbh instruction for R1. I will have a look
and provide a v2 soon.
--
markos
