private void ProcessState(HashSet <Symbol> definitelyAssigned, LocalState state1, LocalState?state2opt)
#endif
        {
            foreach (var slot in state1.Assigned.TrueBits())
            {
                if (slot < variableBySlot.Length &&
                    state2opt?.IsAssigned(slot) != false &&
                    variableBySlot[slot].Symbol is { } symbol&&
                    symbol.Kind != SymbolKind.Field)
                {
                    definitelyAssigned.Add(symbol);
                }
            }
        }