/// <summary>
/// For a variable v, if, according to iv, its value is the same as one of the
/// variables kept on the top of stack, remove that value from the top of the stack.
///
/// </summary>
/// <param name="v"> The variable.</param>
/// <param name="iv"> An InitializedVariables data structure, where an EGraph supposedly
/// maintains the alias information.
/// </param>
public void RemoveVar(Variable v, InitializedVariables iv) {
if (layers!= null && layers.Count != 0) {
HashSet set = (HashSet)layers.Peek();
ArrayList toDelete = new ArrayList();
foreach (Variable u in set) {
if (iv.HasSameValue(u, v)) {
toDelete.Add(u);
}
}
if (toDelete.Count != 0) {
foreach (object o in toDelete) {
set.Remove(o);
}
}
}
}
/// <summary>
/// Whether a value or its alias is contained in a set, according to iv
///
/// iv contains alias information.
/// </summary>
static bool ContainsValueOf(Variable v, InitializedVariables iv, HashSet set) {
foreach (Variable u in set) {
if (iv.HasSameValue(u, v)) {
return true;
}
}
return false;
}