[pypy-dev] Question about Atomic_ops.h in STM

Hi Folks: I noticed a compare_and_swap function in atomic_ops.h. On the IRC channel, it was suggested that I look in _rffi_stm.py. However it is not there (I can understand thta). How can this function be exposed to a RPython programme? The reason I am asking is if compare and swap functions are available, it ought to be possible to write stuff like a lock-free list. Also this give me a chance to learn more about RPython. Cheers, Andrew