[Vm-dev] pluginizing Galois Fields

[David T. Lewis]

On Fri, Dec 18, 2015 at 08:13:00PM -0500, Robert Withers wrote:
> 
> On 12/18/2015 08:07 PM, David T. Lewis wrote:
> >
> >If you are implementing your algorithm from scratch, then it would be
> >nice if it could be done in Smalltalk, because that means we can all
> >read it, play with it in the image, and write unit tests to validate and
> >document its behavior. We can figure out the translation to C afterwords,
> >once you have a good implementation in Smalltalk (and yes I will help
> >with that).
> 
> I have a smalltalk implmentation that came from Google Java code and is 
> fully implemented in squeak/pharo. I am intermittently fixing byte 
> mutations in the payload, so it is working to a degree. Check out the 
> classes GenericGF, GenericGFPoly and GaloisField to see the insides.  
> FECEncoder and FECDecoder are calling the galoisField which builds a 
> ReedSolomon Decoder. That last is where the error detection occurs.
> 
> Thank you all very much for looking out!

I guess my suggestion would be that once you have a fairly good working
implementation that you are comfortable with from a functional point of
view, then let's look at which methods in that implementation would benefit
from being translated to primitives in C. It would be especially good if
you can run a profiler on your Smalltalk implementation and see where the
time is being spent. Those would be the things we would want to turn into
primitives. But first things first, let's get it working 100% (not "to a
degree") and then we can do the translation to primitives.

Dave