protected virtual LBDDNode MakeOrReturn(int var, LBDDNode.Labeling lab, LBDDNode high, LBDDNode low)
{
var t = Tuple.Create(var, lab, high.GetId(), low.GetId());
if (high.GetId() == low.GetId())
{
return(low);
}
if (_hashTable.ContainsKey(t))
{
return(_hashTable[t]);
}
LBDDNode node;
if (lab == LBDDNode.Labeling.Double)
{
// ite(&x, 0, 1)=ite($x, 1, 0)
// ite(&x, 0, K)=ite($x, K, 0)
if (high.GetId() == Zero.GetId())
{
t = Tuple.Create(var, LBDDNode.Labeling.Negate, low.GetId(), Zero.GetId());
node = new LBDDNode(var, _id, Zero, low, LBDDNode.Labeling.Negate);
}
// ite(&x, 1, 0)=ite(x, 1, 0)
// ite(&x, 1, K)=ite(x, 1, K)
else if (high.GetId() == One.GetId())
{
t = Tuple.Create(var, LBDDNode.Labeling.Non, high.GetId(), low.GetId());
node = new LBDDNode(var, _id, low, high, LBDDNode.Labeling.Non);
}
// ite(&x, H, 0)=ite(x, H, 0)
else if (low.GetId() == Zero.GetId())
{
t = Tuple.Create(var, LBDDNode.Labeling.Non, low.GetId(), Zero.GetId());
node = new LBDDNode(var, _id, Zero, high, LBDDNode.Labeling.Non);
}
// ite(&x, H, 1)=ite($x, 1, H)
else if (low.GetId() == One.GetId())
{
t = Tuple.Create(var, LBDDNode.Labeling.Negate, One.GetId(), high.GetId());
node = new LBDDNode(var, _id, high, One, LBDDNode.Labeling.Negate);
}
else
{
node = new LBDDNode(var, _id, low, high, lab);
}
if (_hashTable.ContainsKey(t))
{
return(_hashTable[t]);
}
}
else
{
node = new LBDDNode(var, _id, low, high, lab);
}
_id++;
_hashTable.Add(t, node);
return(node);
}
public virtual LBDDNode AND(LBDDNode H, LBDDNode K)
{
// h & 0 = 0 & k = 0
if (H.GetId() == Zero.GetId() || K.GetId() == Zero.GetId())
{
return(Zero);
}
// 1 & k = k
if (H.GetId() == One.GetId())
{
return(K);
}
// h & 1 = h
if (K.GetId() == One.GetId())
{
return(H);
}
//h==k
if (K.GetId() == H.GetId())
{
return(K);
}
//f&g == g&f, сначала с меньшим номером, потом с большим
var t = H.GetId() > K.GetId()
? Tuple.Create(K.GetId(), H.GetId())
: Tuple.Create(H.GetId(), K.GetId());
// была ли такая операция раньше
if (_andCache.ContainsKey(t))
{
return(_andCache[t]);
}
int top = TopVar(H, K);
LBDDNode low = null, high = null;
LBDDNode.Labeling lab = LBDDNode.Labeling.Non;
var h1 = Contraction(H, top, true);
var h0 = Contraction(H, top, false);
var k1 = Contraction(K, top, true);
var k0 = Contraction(K, top, false);
// постро построение bdd без гнс
//Different variables, any label
if (H.GetVarId() != K.GetVarId())
{
if (H.GetVarId() == top)
{
low = AND(h0, K);
high = AND(h1, K);
lab = H.Label;
}
else //if (k.GetVarId() == top)
{
low = AND(H, k0);
high = AND(H, k1);
lab = K.Label;
}
}
else
{
//Same variable, same label
if (H.Label == K.Label)
{
high = AND(h1, k1);
low = AND(h0, k0);
lab = H.Label;
}
//Same variable, diff labels
// H = ite(&x, H1 , H0) and K = ite(x, K1 , K0) =>
// H and K = ite(&x, (H1 and K1), (H0 and K0))
else if (H.IsNormal() && K.IsDouble() || H.IsDouble() && K.IsNormal())
{
lab = LBDDNode.Labeling.Double;
high = AND(h1, k1);
low = AND(h0, k0);
}
else
{
lab = LBDDNode.Labeling.Double;
// H = ite (x, H1, H0) and K = ite($x, K1 , K0) ||
// H = ite (&x, H1, H0) and K = ite($x, K1 , K0) =>
// H and K = ite(&x, (H1 and K0), (H0 and K1))
if (K.IsNegate())
{
high = AND(h1, k0);
low = AND(h0, k1);
}
else
{
high = AND(h0, k1);
low = AND(h1, k0);
}
}
}
var node = MakeOrReturn(top, lab, high, low);
_andCache.Add(t, node);
return(node);
}
public virtual LBDDNode OR(LBDDNode H, LBDDNode K)
{
// (h||1) = (1||k) = 1
if (H.GetId() == One.GetId() || K.GetId() == One.GetId())
{
return(One);
}
// (0||k) = k
if (H.GetId() == Zero.GetId())
{
return(K);
}
// (h||0) = h
if (K.GetId() == Zero.GetId())
{
return(H);
}
//f||g == g||f, сначала с меньшим номером, потом с большим
var t = H.GetId() > K.GetId()
? Tuple.Create(K.GetId(), H.GetId())
: Tuple.Create(H.GetId(), K.GetId());
if (_orCache.ContainsKey(t))
{
return(_orCache[t]);
}
int top = TopVar(H, K);
LBDDNode low = null, high = null;
LBDDNode.Labeling lab = LBDDNode.Labeling.Non;
var h1 = Contraction(H, top, true);
var h0 = Contraction(H, top, false);
var k1 = Contraction(K, top, true);
var k0 = Contraction(K, top, false);
//Different variables, any label
if (H.GetVarId() != K.GetVarId())
{
if (H.GetVarId() == top)
{
low = OR(h0, K);
high = OR(h1, K);
lab = H.Label;
}
else //if (k.GetVarId() == top)
{
low = OR(H, k0);
high = OR(H, k1);
lab = K.Label;
}
}
else
{
//Same variable, same label
if (H.Label == K.Label)
{
high = OR(h1, k1);
low = OR(h0, k0);
lab = H.Label;
}
//Same variable, diff labels
// H = ite(&x, H1 , H0) OR K = ite(x, K1 , K0) =>
// H OR K = ite(&x, (H1 OR K1), (H0 OR K0))
else if (H.IsNormal() && K.IsDouble() || H.IsDouble() && K.IsNormal())
{
lab = LBDDNode.Labeling.Double;
high = OR(h1, k1);
low = OR(h0, k0);
}
else
{
lab = LBDDNode.Labeling.Double;
// H = ite (x, H1, H0) OR K = ite($x, K1 , K0) ||
// H = ite (&x, H1, H0) OR K = ite($x, K1 , K0) =>
// H OR K = ite(&x, (H1 OR K0), (H0 OR K1))
if (K.IsNegate())
{
high = OR(h1, k0);
low = OR(h0, k1);
}
else
{
high = OR(h0, k1);
low = OR(h1, k0);
}
}
}
var node = MakeOrReturn(top, lab, high, low);
_orCache.Add(t, node);
return(node);
}