/// <summary>
/// Encode this assignment in a sequence of statements. Return variable values after this assignment based on the current value in resultBefore
/// [ REFS: 'result', DEREFS: 'resultBefore' ]
/// </summary>
public override ExpressionBDDEncoding TranslateStatementToBDD(ExpressionBDDEncoding resultBefore, Model model)
{
ExpressionBDDEncoding newUpdate = this.TranslateBoolExpToBDD(model);
ExpressionBDDEncoding tempResult = new ExpressionBDDEncoding();
List<List<int>> updatedVariablesInNewUpdate = new List<List<int>>();
for (int index = 0; index < newUpdate.Count(); index++)
{
updatedVariablesInNewUpdate.Add(model.GetColSupportedVars(newUpdate.GuardDDs[index]));
}
List<List<int>> usedVariableInNewUpdate = new List<List<int>>();
for (int index = 0; index < newUpdate.Count(); index++)
{
usedVariableInNewUpdate.Add(model.GetRowSupportedVars(newUpdate.GuardDDs[index]));
}
List<List<int>> updatedVariablesBefore = new List<List<int>>();
for (int index = 0; index < resultBefore.Count(); index++)
{
updatedVariablesBefore.Add(model.GetColSupportedVars(resultBefore.GuardDDs[index]));
}
for (int j1 = 0; j1 < resultBefore.Count(); j1++)
{
for (int j2 = 0; j2 < newUpdate.Count(); j2++)
{
//a variable is already updated, now is updated again and it also apprears in the value expression
if (Assignment.IsComplexUpdate(updatedVariablesBefore[j1], updatedVariablesInNewUpdate[j2], usedVariableInNewUpdate[j2]))
{
model.CreateTemporaryVar();
Expression newUpdate1;
Expression newUpdate2;
PropertyAssignment assignment = this as PropertyAssignment;
newUpdate1 = new Assignment(Model.TEMPORARY_VARIABLE, this.RightHandExpression);
newUpdate2 = new PropertyAssignment(this.RecordExpression, this.PropertyExpression, new Variable(Model.TEMPORARY_VARIABLE));
resultBefore.Ref();
ExpressionBDDEncoding tempResult1 = newUpdate1.TranslateStatementToBDD(resultBefore, model);
ExpressionBDDEncoding tempResult2 = newUpdate2.TranslateStatementToBDD(tempResult1, model);
//Remove the temporary variable from transition
for (int i = 0; i < tempResult2.Count(); i++)
{
tempResult2.GuardDDs[i] = CUDD.Abstract.ThereExists(tempResult2.GuardDDs[i], model.GetRowVars(Model.TEMPORARY_VARIABLE));
tempResult2.GuardDDs[i] = CUDD.Abstract.ThereExists(tempResult2.GuardDDs[i], model.GetColVars(Model.TEMPORARY_VARIABLE));
tempResult.AddNodeToGuard(tempResult2.GuardDDs[i]);
}
}
else
{
//swap row, col updated variable in result in the new update command expression
CUDDNode update2 = newUpdate.GuardDDs[j2];
CUDD.Ref(update2);
foreach (int index in updatedVariablesBefore[j1])
{
if (usedVariableInNewUpdate[j2].Contains(index))
{
update2 = CUDD.Variable.SwapVariables(update2, model.GetColVars(index), model.GetRowVars(index));
}
}
//Restrict updated variable in new update of the old update
CUDDNode update1 = resultBefore.GuardDDs[j1];
CUDD.Ref(update1);
foreach (int index in updatedVariablesInNewUpdate[j2])
{
if (updatedVariablesBefore[j1].Contains(index))
{
update1 = CUDD.Abstract.ThereExists(update1, model.GetColVars(index));
}
}
CUDDNode transition = CUDD.Function.And(update1, update2);
tempResult.AddNodeToGuard(transition);
}
}
}
resultBefore.DeRef();
newUpdate.DeRef();
return tempResult;
}
/// <summary>
/// Return the variable values after the assignment based on the current variable values in resultBefore
/// [ REFS: 'result', DEREFS: 'resultBefore' ]
/// </summary>
public override ExpressionBDDEncoding TranslateStatementToBDD(ExpressionBDDEncoding resultBefore, Model model)
{
ExpressionBDDEncoding newUpdate = this.TranslateBoolExpToBDD(model);
ExpressionBDDEncoding tempResult = new ExpressionBDDEncoding();
List <List <int> > updatedVariablesInNewUpdate = new List <List <int> >();
for (int index = 0; index < newUpdate.Count(); index++)
{
updatedVariablesInNewUpdate.Add(model.GetColSupportedVars(newUpdate.GuardDDs[index]));
}
List <List <int> > usedVariableInNewUpdate = new List <List <int> >();
for (int index = 0; index < newUpdate.Count(); index++)
{
usedVariableInNewUpdate.Add(model.GetRowSupportedVars(newUpdate.GuardDDs[index]));
}
List <List <int> > updatedVariablesBefore = new List <List <int> >();
for (int index = 0; index < resultBefore.Count(); index++)
{
updatedVariablesBefore.Add(model.GetColSupportedVars(resultBefore.GuardDDs[index]));
}
for (int j1 = 0; j1 < resultBefore.Count(); j1++)
{
for (int j2 = 0; j2 < newUpdate.Count(); j2++)
{
//a variable is already updated, now is updated again and it also apprears in the value expression
if (IsComplexUpdate(updatedVariablesBefore[j1], updatedVariablesInNewUpdate[j2], usedVariableInNewUpdate[j2]))
{
model.CreateTemporaryVar();
Expression newUpdate1;
Expression newUpdate2;
newUpdate1 = new Assignment(Model.TEMPORARY_VARIABLE, this.RightHandSide);
newUpdate2 = new Assignment(this.LeftHandSide, new Variable(Model.TEMPORARY_VARIABLE));
resultBefore.Ref();
ExpressionBDDEncoding tempResult1 = newUpdate1.TranslateStatementToBDD(resultBefore, model);
ExpressionBDDEncoding tempResult2 = newUpdate2.TranslateStatementToBDD(tempResult1, model);
for (int i = 0; i < tempResult2.Count(); i++)
{
tempResult2.GuardDDs[i] = CUDD.Abstract.ThereExists(tempResult2.GuardDDs[i], model.GetRowVars(model.GetVarIndex(Model.TEMPORARY_VARIABLE)));
tempResult2.GuardDDs[i] = CUDD.Abstract.ThereExists(tempResult2.GuardDDs[i], model.GetColVars(model.GetVarIndex(Model.TEMPORARY_VARIABLE)));
tempResult.AddNodeToGuard(tempResult2.GuardDDs[i]);
}
}
else
{
//swap row, col updated variable in result in the new update command expression
CUDDNode update2 = newUpdate.GuardDDs[j2];
CUDD.Ref(update2);
foreach (int index in updatedVariablesBefore[j1])
{
if (usedVariableInNewUpdate[j2].Contains(index))
{
update2 = CUDD.Variable.SwapVariables(update2, model.GetColVars(index), model.GetRowVars(index));
}
}
//Restrict updated variable in new update of the old update
CUDDNode update1 = resultBefore.GuardDDs[j1];
CUDD.Ref(update1);
foreach (int index in updatedVariablesInNewUpdate[j2])
{
if (updatedVariablesBefore[j1].Contains(index))
{
update1 = CUDD.Abstract.ThereExists(update1, model.GetColVars(index));
}
}
CUDDNode transition = CUDD.Function.And(update1, update2);
tempResult.AddNodeToGuard(transition);
}
}
}
resultBefore.DeRef();
newUpdate.DeRef();
return(tempResult);
}
