class ThreadSafe::Util::Striped64::Cell

form of CAS here, if it were provided.
Optimisation note: It would be possible to use a release-only
reorder them.
The value field is placed between pads, hoping that the JVM doesn’t
Padded variant of AtomicLong supporting only raw accesses plus CAS.

def cas_computed 

def cas_computed
  cas(current_value = value, yield(current_value))
end