Method GetNumber

library/src/system/scheduler.cpp:763–842

schedType Scheduler::GetNumber(const int thrId)
{
  const unsigned tu = static_cast<unsigned>(thrId);
  int g = threadGroup[tu];
  listType * lp;
  schedType st;

  if (g == -1)
  {
    // Find a new group

    if (currGroup >= numGroups - 1)
    {
      // Out of groups. Just an optimization not to touch the
      // shared variable unnecessarily.
      st.number = -1;
      return st;
    }

    // Atomic.
    g = ++currGroup;

    if (g >= numGroups)
    {
      // Out of groups. currGroup could have changed in the
      // meantime in another thread, so test again.

      st.number = -1;
      return st;
    }

    // A bit inelegant to duplicate this, but seems better than
    // the alternative, as threadGroup must get set to -1 in some
    // cases.
    threadGroup[tu] = g;
    threadCurrGroup[tu] = g;
    group[g].repeatNo = 0;
    group[g].actual = 0;
  }

  // Continue with existing or new group

  int strain = group[g].strain;
  int key = group[g].hash;

  lp = &list[strain][key];
  st.number = lp->first;
  lp->first = hands[lp->first].next;

  if (group[g].repeatNo == 0)
  {
    group[g].head = st.number;
    st.repeatOf = -1;

    // Only first-solve suited hands for statistics right now.
    hands[st.number].selectFlag =
      (hands[st.number].strain == 4 ? 1 : 0);
  }