Porting Sable VM to SH4

Hello,

I'm currently trying to port the Sable VM to the SH4 platform, but my 
attempts have not yet succeeded. I've been google-ing for this problem, 
but I am not really satisfied with what I found during my search (small 
bits of information everywhere but nothing really of much use). 
Therefore my questions to this Sable VM developers group:

- Has some work already been done on this subject?
- If the work has already been done, can anyone provide me with a snapshot?
- If not, is there any place where I could find the unfinished attempts? 
This would be a good starting point for me, certainly the 
compare_and_swap atomic operation in system.c.

Thanks in advance,

Vincent