InterlockedCompareExchange64 (volatile gint64 * dest, gint64 exch, gint64 comp)
{
  gint64 D.7940;
  gint64 old;

  pthread_mutex_lock (&spin);
  old = *dest;
  if (old == comp) goto <D.7938>; else goto <D.7939>;
  <D.7938>:
  *dest = exch;
  <D.7939>:
  pthread_mutex_unlock (&spin);
  D.7940 = old;
  return D.7940;
}