/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addMatrixMultiply.]
Description [Performs the recursive step of Cudd_addMatrixMultiply.
Returns a pointer to the result if successful; NULL otherwise.]
SideEffects [None]
******************************************************************************/
static DdNode *
addMMRecur(
DdManager * dd,
DdNode * A,
DdNode * B,
int topP,
int * vars)
{
DdNode *zero,
*At, /* positive cofactor of first operand */
*Ae, /* negative cofactor of first operand */
*Bt, /* positive cofactor of second operand */
*Be, /* negative cofactor of second operand */
*t, /* positive cofactor of result */
*e, /* negative cofactor of result */
*scaled, /* scaled result */
*add_scale, /* ADD representing the scaling factor */
*res;
int i; /* loop index */
double scale; /* scaling factor */
int index; /* index of the top variable */
CUDD_VALUE_TYPE value;
unsigned int topA, topB, topV;
DD_CTFP cacheOp;
statLine(dd);
zero = DD_ZERO(dd);
if (A == zero || B == zero) {
return(zero);
}
if (cuddIsConstant(A) && cuddIsConstant(B)) {
/* Compute the scaling factor. It is 2^k, where k is the
** number of summation variables below the current variable.
** Indeed, these constants represent blocks of 2^k identical
** constant values in both A and B.
*/
value = cuddV(A) * cuddV(B);
for (i = 0; i < dd->size; i++) {
if (vars[i]) {
if (dd->perm[i] > topP) {
value *= (CUDD_VALUE_TYPE) 2;
}
}
}
res = cuddUniqueConst(dd, value);
return(res);
}
/* Standardize to increase cache efficiency. Clearly, A*B != B*A
** in matrix multiplication. However, which matrix is which is
** determined by the variables appearing in the ADDs and not by
** which one is passed as first argument.
*/
if (A > B) {
DdNode *tmp = A;
A = B;
B = tmp;
}
topA = cuddI(dd,A->index); topB = cuddI(dd,B->index);
topV = ddMin(topA,topB);
cacheOp = (DD_CTFP) addMMRecur;
res = cuddCacheLookup2(dd,cacheOp,A,B);
if (res != NULL) {
/* If the result is 0, there is no need to normalize.
** Otherwise we count the number of z variables between
** the current depth and the top of the ADDs. These are
** the missing variables that determine the size of the
** constant blocks.
*/
if (res == zero) return(res);
scale = 1.0;
for (i = 0; i < dd->size; i++) {
if (vars[i]) {
if (dd->perm[i] > topP && (unsigned) dd->perm[i] < topV) {
scale *= 2;
}
}
}
if (scale > 1.0) {
cuddRef(res);
add_scale = cuddUniqueConst(dd,(CUDD_VALUE_TYPE)scale);
if (add_scale == NULL) {
Cudd_RecursiveDeref(dd, res);
return(NULL);
}
cuddRef(add_scale);
scaled = cuddAddApplyRecur(dd,Cudd_addTimes,res,add_scale);
if (scaled == NULL) {
Cudd_RecursiveDeref(dd, add_scale);
Cudd_RecursiveDeref(dd, res);
return(NULL);
}
cuddRef(scaled);
Cudd_RecursiveDeref(dd, add_scale);
Cudd_RecursiveDeref(dd, res);
res = scaled;
cuddDeref(res);
}
return(res);
}
/* compute the cofactors */
if (topV == topA) {
At = cuddT(A);
Ae = cuddE(A);
} else {
At = Ae = A;
}
if (topV == topB) {
Bt = cuddT(B);
Be = cuddE(B);
} else {
Bt = Be = B;
}
t = addMMRecur(dd, At, Bt, (int)topV, vars);
if (t == NULL) return(NULL);
cuddRef(t);
e = addMMRecur(dd, Ae, Be, (int)topV, vars);
if (e == NULL) {
Cudd_RecursiveDeref(dd, t);
return(NULL);
}
cuddRef(e);
index = dd->invperm[topV];
if (vars[index] == 0) {
/* We have split on either the rows of A or the columns
** of B. We just need to connect the two subresults,
** which correspond to two submatrices of the result.
*/
res = (t == e) ? t : cuddUniqueInter(dd,index,t,e);
if (res == NULL) {
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
return(NULL);
}
cuddRef(res);
cuddDeref(t);
cuddDeref(e);
} else {
/* we have simultaneously split on the columns of A and
** the rows of B. The two subresults must be added.
*/
res = cuddAddApplyRecur(dd,Cudd_addPlus,t,e);
if (res == NULL) {
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
}
cuddCacheInsert2(dd,cacheOp,A,B,res);
/* We have computed (and stored in the computed table) a minimal
** result; that is, a result that assumes no summation variables
** between the current depth of the recursion and its top
** variable. We now take into account the z variables by properly
** scaling the result.
*/
if (res != zero) {
scale = 1.0;
for (i = 0; i < dd->size; i++) {
if (vars[i]) {
if (dd->perm[i] > topP && (unsigned) dd->perm[i] < topV) {
scale *= 2;
}
}
}
if (scale > 1.0) {
add_scale = cuddUniqueConst(dd,(CUDD_VALUE_TYPE)scale);
if (add_scale == NULL) {
Cudd_RecursiveDeref(dd, res);
return(NULL);
}
cuddRef(add_scale);
scaled = cuddAddApplyRecur(dd,Cudd_addTimes,res,add_scale);
if (scaled == NULL) {
Cudd_RecursiveDeref(dd, res);
Cudd_RecursiveDeref(dd, add_scale);
return(NULL);
}
cuddRef(scaled);
Cudd_RecursiveDeref(dd, add_scale);
Cudd_RecursiveDeref(dd, res);
res = scaled;
}
}
cuddDeref(res);
return(res);
} /* end of addMMRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_bddIsop.]
Description []
SideEffects [None]
SeeAlso [Cudd_bddIsop]
******************************************************************************/
DdNode *
cuddBddIsop(
DdManager * dd,
DdNode * L,
DdNode * U)
{
DdNode *one = DD_ONE(dd);
DdNode *zero = Cudd_Not(one);
int v, top_l, top_u;
DdNode *Lsub0, *Usub0, *Lsub1, *Usub1, *Ld, *Ud;
DdNode *Lsuper0, *Usuper0, *Lsuper1, *Usuper1;
DdNode *Isub0, *Isub1, *Id;
DdNode *x;
DdNode *term0, *term1, *sum;
DdNode *Lv, *Uv, *Lnv, *Unv;
DdNode *r;
int index;
statLine(dd);
if (L == zero)
return(zero);
if (U == one)
return(one);
/* Check cache */
r = cuddCacheLookup2(dd, cuddBddIsop, L, U);
if (r)
return(r);
top_l = dd->perm[Cudd_Regular(L)->index];
top_u = dd->perm[Cudd_Regular(U)->index];
v = ddMin(top_l, top_u);
/* Compute cofactors */
if (top_l == v) {
index = Cudd_Regular(L)->index;
Lv = Cudd_T(L);
Lnv = Cudd_E(L);
if (Cudd_IsComplement(L)) {
Lv = Cudd_Not(Lv);
Lnv = Cudd_Not(Lnv);
}
}
else {
index = Cudd_Regular(U)->index;
Lv = Lnv = L;
}
if (top_u == v) {
Uv = Cudd_T(U);
Unv = Cudd_E(U);
if (Cudd_IsComplement(U)) {
Uv = Cudd_Not(Uv);
Unv = Cudd_Not(Unv);
}
}
else {
Uv = Unv = U;
}
Lsub0 = cuddBddAndRecur(dd, Lnv, Cudd_Not(Uv));
if (Lsub0 == NULL)
return(NULL);
Cudd_Ref(Lsub0);
Usub0 = Unv;
Lsub1 = cuddBddAndRecur(dd, Lv, Cudd_Not(Unv));
if (Lsub1 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
return(NULL);
}
Cudd_Ref(Lsub1);
Usub1 = Uv;
Isub0 = cuddBddIsop(dd, Lsub0, Usub0);
if (Isub0 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
return(NULL);
}
Cudd_Ref(Isub0);
Isub1 = cuddBddIsop(dd, Lsub1, Usub1);
if (Isub1 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
Cudd_RecursiveDeref(dd, Isub0);
return(NULL);
}
Cudd_Ref(Isub1);
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
Lsuper0 = cuddBddAndRecur(dd, Lnv, Cudd_Not(Isub0));
if (Lsuper0 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
return(NULL);
}
Cudd_Ref(Lsuper0);
Lsuper1 = cuddBddAndRecur(dd, Lv, Cudd_Not(Isub1));
if (Lsuper1 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
return(NULL);
}
Cudd_Ref(Lsuper1);
Usuper0 = Unv;
Usuper1 = Uv;
/* Ld = Lsuper0 + Lsuper1 */
Ld = cuddBddAndRecur(dd, Cudd_Not(Lsuper0), Cudd_Not(Lsuper1));
Ld = Cudd_NotCond(Ld, Ld != NULL);
if (Ld == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
return(NULL);
}
Cudd_Ref(Ld);
Ud = cuddBddAndRecur(dd, Usuper0, Usuper1);
if (Ud == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
Cudd_RecursiveDeref(dd, Ld);
return(NULL);
}
Cudd_Ref(Ud);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
Id = cuddBddIsop(dd, Ld, Ud);
if (Id == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Ld);
Cudd_RecursiveDeref(dd, Ud);
return(NULL);
}
Cudd_Ref(Id);
Cudd_RecursiveDeref(dd, Ld);
Cudd_RecursiveDeref(dd, Ud);
x = cuddUniqueInter(dd, index, one, zero);
if (x == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Id);
return(NULL);
}
Cudd_Ref(x);
term0 = cuddBddAndRecur(dd, Cudd_Not(x), Isub0);
if (term0 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDeref(dd, x);
return(NULL);
}
Cudd_Ref(term0);
Cudd_RecursiveDeref(dd, Isub0);
term1 = cuddBddAndRecur(dd, x, Isub1);
if (term1 == NULL) {
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDeref(dd, x);
Cudd_RecursiveDeref(dd, term0);
return(NULL);
}
Cudd_Ref(term1);
Cudd_RecursiveDeref(dd, x);
Cudd_RecursiveDeref(dd, Isub1);
/* sum = term0 + term1 */
sum = cuddBddAndRecur(dd, Cudd_Not(term0), Cudd_Not(term1));
sum = Cudd_NotCond(sum, sum != NULL);
if (sum == NULL) {
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDeref(dd, term0);
Cudd_RecursiveDeref(dd, term1);
return(NULL);
}
Cudd_Ref(sum);
Cudd_RecursiveDeref(dd, term0);
Cudd_RecursiveDeref(dd, term1);
/* r = sum + Id */
r = cuddBddAndRecur(dd, Cudd_Not(sum), Cudd_Not(Id));
r = Cudd_NotCond(r, r != NULL);
if (r == NULL) {
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDeref(dd, sum);
return(NULL);
}
Cudd_Ref(r);
Cudd_RecursiveDeref(dd, sum);
Cudd_RecursiveDeref(dd, Id);
cuddCacheInsert2(dd, cuddBddIsop, L, U, r);
Cudd_Deref(r);
return(r);
} /* end of cuddBddIsop */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addUnivAbstract.]
Description [Performs the recursive step of Cudd_addUnivAbstract.
Returns the ADD obtained by abstracting the variables of cube from f,
if successful; NULL otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddAddUnivAbstractRecur(
DdManager * manager,
DdNode * f,
DdNode * cube)
{
DdNode *T, *E, *res, *res1, *res2, *one, *zero;
statLine(manager);
one = DD_ONE(manager);
zero = DD_ZERO(manager);
/* Cube is guaranteed to be a cube at this point.
** zero and one are the only constatnts c such that c*c=c.
*/
if (f == zero || f == one || cube == one) {
return(f);
}
/* Abstract a variable that does not appear in f. */
if (cuddI(manager,f->index) > cuddI(manager,cube->index)) {
res1 = cuddAddUnivAbstractRecur(manager, f, cuddT(cube));
if (res1 == NULL) return(NULL);
cuddRef(res1);
/* Use the "internal" procedure to be alerted in case of
** dynamic reordering. If dynamic reordering occurs, we
** have to abort the entire abstraction.
*/
res = cuddAddApplyRecur(manager, Cudd_addTimes, res1, res1);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,res1);
cuddDeref(res);
return(res);
}
if ((res = cuddCacheLookup2(manager, Cudd_addUnivAbstract, f, cube)) != NULL) {
return(res);
}
T = cuddT(f);
E = cuddE(f);
/* If the two indices are the same, so are their levels. */
if (f->index == cube->index) {
res1 = cuddAddUnivAbstractRecur(manager, T, cuddT(cube));
if (res1 == NULL) return(NULL);
cuddRef(res1);
res2 = cuddAddUnivAbstractRecur(manager, E, cuddT(cube));
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = cuddAddApplyRecur(manager, Cudd_addTimes, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
cuddCacheInsert2(manager, Cudd_addUnivAbstract, f, cube, res);
cuddDeref(res);
return(res);
} else { /* if (cuddI(manager,f->index) < cuddI(manager,cube->index)) */
res1 = cuddAddUnivAbstractRecur(manager, T, cube);
if (res1 == NULL) return(NULL);
cuddRef(res1);
res2 = cuddAddUnivAbstractRecur(manager, E, cube);
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = (res1 == res2) ? res1 :
cuddUniqueInter(manager, (int) f->index, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddDeref(res1);
cuddDeref(res2);
cuddCacheInsert2(manager, Cudd_addUnivAbstract, f, cube, res);
return(res);
}
} /* end of cuddAddUnivAbstractRecur */
/**Function********************************************************************
Synopsis [Approximates the AND of two BDDs and simultaneously abstracts the
variables in cube.]
Description [Approximates the AND of two BDDs and simultaneously
abstracts the variables in cube. The variables are existentially
abstracted. Returns a pointer to the result is successful; NULL
otherwise.]
SideEffects [None]
SeeAlso [Cudd_bddClippingAndAbstract]
******************************************************************************/
static DdNode *
cuddBddClipAndAbsRecur(
DdManager * manager,
DdNode * f,
DdNode * g,
DdNode * cube,
int distance,
int direction)
{
DdNode *F, *ft, *fe, *G, *gt, *ge;
DdNode *one, *zero, *r, *t, *e, *Cube;
unsigned int topf, topg, topcube, top, index;
ptruint cacheTag;
statLine(manager);
one = DD_ONE(manager);
zero = Cudd_Not(one);
/* Terminal cases. */
if (f == zero || g == zero || f == Cudd_Not(g)) return(zero);
if (f == one && g == one) return(one);
if (cube == one) {
return(cuddBddClippingAndRecur(manager, f, g, distance, direction));
}
if (f == one || f == g) {
return (cuddBddExistAbstractRecur(manager, g, cube));
}
if (g == one) {
return (cuddBddExistAbstractRecur(manager, f, cube));
}
if (distance == 0) return(Cudd_NotCond(one,(direction == 0)));
/* At this point f, g, and cube are not constant. */
distance--;
/* Check cache. */
if (f > g) { /* Try to increase cache efficiency. */
DdNode *tmp = f;
f = g; g = tmp;
}
F = Cudd_Regular(f);
G = Cudd_Regular(g);
cacheTag = direction ? DD_BDD_CLIPPING_AND_ABSTRACT_UP_TAG :
DD_BDD_CLIPPING_AND_ABSTRACT_DOWN_TAG;
if (F->ref != 1 || G->ref != 1) {
r = cuddCacheLookup(manager, cacheTag,
f, g, cube);
if (r != NULL) {
return(r);
}
}
/* Here we can skip the use of cuddI, because the operands are known
** to be non-constant.
*/
topf = manager->perm[F->index];
topg = manager->perm[G->index];
top = ddMin(topf, topg);
topcube = manager->perm[cube->index];
if (topcube < top) {
return(cuddBddClipAndAbsRecur(manager, f, g, cuddT(cube),
distance, direction));
}
/* Now, topcube >= top. */
if (topf == top) {
index = F->index;
ft = cuddT(F);
fe = cuddE(F);
if (Cudd_IsComplement(f)) {
ft = Cudd_Not(ft);
fe = Cudd_Not(fe);
}
} else {
index = G->index;
ft = fe = f;
}
if (topg == top) {
gt = cuddT(G);
ge = cuddE(G);
if (Cudd_IsComplement(g)) {
gt = Cudd_Not(gt);
ge = Cudd_Not(ge);
}
} else {
gt = ge = g;
}
if (topcube == top) {
Cube = cuddT(cube);
} else {
Cube = cube;
}
t = cuddBddClipAndAbsRecur(manager, ft, gt, Cube, distance, direction);
if (t == NULL) return(NULL);
/* Special case: 1 OR anything = 1. Hence, no need to compute
** the else branch if t is 1.
*/
if (t == one && topcube == top) {
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert(manager, cacheTag, f, g, cube, one);
return(one);
}
cuddRef(t);
e = cuddBddClipAndAbsRecur(manager, fe, ge, Cube, distance, direction);
if (e == NULL) {
Cudd_RecursiveDeref(manager, t);
return(NULL);
}
cuddRef(e);
if (topcube == top) { /* abstract */
r = cuddBddClippingAndRecur(manager, Cudd_Not(t), Cudd_Not(e),
distance, (direction == 0));
if (r == NULL) {
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
return(NULL);
}
r = Cudd_Not(r);
cuddRef(r);
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
cuddDeref(r);
} else if (t == e) {
r = t;
cuddDeref(t);
cuddDeref(e);
} else {
if (Cudd_IsComplement(t)) {
r = cuddUniqueInter(manager,(int)index,Cudd_Not(t),Cudd_Not(e));
if (r == NULL) {
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
return(NULL);
}
r = Cudd_Not(r);
} else {
r = cuddUniqueInter(manager,(int)index,t,e);
if (r == NULL) {
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
return(NULL);
}
}
cuddDeref(e);
cuddDeref(t);
}
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert(manager, cacheTag, f, g, cube, r);
return (r);
} /* end of cuddBddClipAndAbsRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addApply.]
Description [Performs the recursive step of Cudd_addApply. Returns a
pointer to the result if successful; NULL otherwise.]
SideEffects [None]
SeeAlso [cuddAddMonadicApplyRecur]
******************************************************************************/
DdNode *
cuddAddApplyRecur(
DdManager * dd,
DdNode * (*op)(DdManager *, DdNode **, DdNode **),
DdNode * f,
DdNode * g)
{
DdNode *res,
*fv, *fvn, *gv, *gvn,
*T, *E;
unsigned int ford, gord;
unsigned int index;
DdNode *(*cacheOp)(DdManager *, DdNode *, DdNode *);
/* Check terminal cases. Op may swap f and g to increase the
* cache hit rate.
*/
statLine(dd);
res = (*op)(dd,&f,&g);
if (res != NULL) return(res);
/* Check cache. */
cacheOp = (DdNode *(*)(DdManager *, DdNode *, DdNode *)) op;
res = cuddCacheLookup2(dd,cacheOp,f,g);
if (res != NULL) return(res);
/* Recursive step. */
ford = cuddI(dd,f->index);
gord = cuddI(dd,g->index);
if (ford <= gord) {
index = f->index;
fv = cuddT(f);
fvn = cuddE(f);
} else {
index = g->index;
fv = fvn = f;
}
if (gord <= ford) {
gv = cuddT(g);
gvn = cuddE(g);
} else {
gv = gvn = g;
}
T = cuddAddApplyRecur(dd,op,fv,gv);
if (T == NULL) return(NULL);
cuddRef(T);
E = cuddAddApplyRecur(dd,op,fvn,gvn);
if (E == NULL) {
Cudd_RecursiveDeref(dd,T);
return(NULL);
}
cuddRef(E);
res = (T == E) ? T : cuddUniqueInter(dd,(int)index,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert2(dd,cacheOp,f,g,res);
return(res);
} /* end of cuddAddApplyRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddDiff.]
Description []
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddZddDiff(
DdManager * zdd,
DdNode * P,
DdNode * Q)
{
int p_top, q_top;
DdNode *empty = DD_ZERO(zdd), *t, *e, *res;
DdManager *table = zdd;
statLine(zdd);
if (P == empty)
return(empty);
if (Q == empty)
return(P);
if (P == Q)
return(empty);
/* Check cache. The cache is shared by Cudd_zddDiffConst(). */
res = cuddCacheLookup2Zdd(table, cuddZddDiff, P, Q);
if (res != NULL && res != DD_NON_CONSTANT)
return(res);
if (cuddIsConstant(P))
p_top = P->index;
else
p_top = zdd->permZ[P->index];
if (cuddIsConstant(Q))
q_top = Q->index;
else
q_top = zdd->permZ[Q->index];
if (p_top < q_top) {
e = cuddZddDiff(zdd, cuddE(P), Q);
if (e == NULL) return(NULL);
cuddRef(e);
res = cuddZddGetNode(zdd, P->index, cuddT(P), e);
if (res == NULL) {
Cudd_RecursiveDerefZdd(table, e);
return(NULL);
}
cuddDeref(e);
} else if (p_top > q_top) {
res = cuddZddDiff(zdd, P, cuddE(Q));
if (res == NULL) return(NULL);
} else {
t = cuddZddDiff(zdd, cuddT(P), cuddT(Q));
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddZddDiff(zdd, cuddE(P), cuddE(Q));
if (e == NULL) {
Cudd_RecursiveDerefZdd(table, t);
return(NULL);
}
cuddRef(e);
res = cuddZddGetNode(zdd, P->index, t, e);
if (res == NULL) {
Cudd_RecursiveDerefZdd(table, t);
Cudd_RecursiveDerefZdd(table, e);
return(NULL);
}
cuddDeref(t);
cuddDeref(e);
}
cuddCacheInsert2(table, cuddZddDiff, P, Q, res);
return(res);
} /* end of cuddZddDiff */
/**Function********************************************************************
Synopsis [Takes the AND of two BDDs and simultaneously abstracts the
variables in cube.]
Description [Takes the AND of two BDDs and simultaneously abstracts
the variables in cube. The variables are existentially abstracted.
Returns a pointer to the result is successful; NULL otherwise.]
SideEffects [None]
SeeAlso [Cudd_bddAndAbstract]
******************************************************************************/
DdNode *
cuddBddAndAbstractRecur(
DdManager * manager,
DdNode * f,
DdNode * g,
DdNode * cube)
{
DdNode *F, *ft, *fe, *G, *gt, *ge;
DdNode *one, *zero, *r, *t, *e;
unsigned int topf, topg, topcube, top, index;
statLine(manager);
one = DD_ONE(manager);
zero = Cudd_Not(one);
/* Terminal cases. */
if (f == zero || g == zero || f == Cudd_Not(g)) return(zero);
if (f == one && g == one) return(one);
if (cube == one) {
return(cuddBddAndRecur(manager, f, g));
}
if (f == one || f == g) {
return(cuddBddExistAbstractRecur(manager, g, cube));
}
if (g == one) {
return(cuddBddExistAbstractRecur(manager, f, cube));
}
/* At this point f, g, and cube are not constant. */
if (f > g) { /* Try to increase cache efficiency. */
DdNode *tmp = f;
f = g;
g = tmp;
}
/* Here we can skip the use of cuddI, because the operands are known
** to be non-constant.
*/
F = Cudd_Regular(f);
G = Cudd_Regular(g);
topf = manager->perm[F->index];
topg = manager->perm[G->index];
top = ddMin(topf, topg);
topcube = manager->perm[cube->index];
while (topcube < top) {
cube = cuddT(cube);
if (cube == one) {
return(cuddBddAndRecur(manager, f, g));
}
topcube = manager->perm[cube->index];
}
/* Now, topcube >= top. */
/* Check cache. */
if (F->ref != 1 || G->ref != 1) {
r = cuddCacheLookup(manager, DD_BDD_AND_ABSTRACT_TAG, f, g, cube);
if (r != NULL) {
return(r);
}
}
if (topf == top) {
index = F->index;
ft = cuddT(F);
fe = cuddE(F);
if (Cudd_IsComplement(f)) {
ft = Cudd_Not(ft);
fe = Cudd_Not(fe);
}
} else {
index = G->index;
ft = fe = f;
}
if (topg == top) {
gt = cuddT(G);
ge = cuddE(G);
if (Cudd_IsComplement(g)) {
gt = Cudd_Not(gt);
ge = Cudd_Not(ge);
}
} else {
gt = ge = g;
}
if (topcube == top) { /* quantify */
DdNode *Cube = cuddT(cube);
t = cuddBddAndAbstractRecur(manager, ft, gt, Cube);
if (t == NULL) return(NULL);
/* Special case: 1 OR anything = 1. Hence, no need to compute
** the else branch if t is 1. Likewise t + t * anything == t.
** Notice that t == fe implies that fe does not depend on the
** variables in Cube. Likewise for t == ge.
*/
if (t == one || t == fe || t == ge) {
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert(manager, DD_BDD_AND_ABSTRACT_TAG,
f, g, cube, t);
return(t);
}
cuddRef(t);
/* Special case: t + !t * anything == t + anything. */
if (t == Cudd_Not(fe)) {
e = cuddBddExistAbstractRecur(manager, ge, Cube);
} else if (t == Cudd_Not(ge)) {
e = cuddBddExistAbstractRecur(manager, fe, Cube);
} else {
e = cuddBddAndAbstractRecur(manager, fe, ge, Cube);
}
if (e == NULL) {
Cudd_IterDerefBdd(manager, t);
return(NULL);
}
if (t == e) {
r = t;
cuddDeref(t);
} else {
cuddRef(e);
r = cuddBddAndRecur(manager, Cudd_Not(t), Cudd_Not(e));
if (r == NULL) {
Cudd_IterDerefBdd(manager, t);
Cudd_IterDerefBdd(manager, e);
return(NULL);
}
r = Cudd_Not(r);
cuddRef(r);
Cudd_DelayedDerefBdd(manager, t);
Cudd_DelayedDerefBdd(manager, e);
cuddDeref(r);
}
} else {
t = cuddBddAndAbstractRecur(manager, ft, gt, cube);
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddBddAndAbstractRecur(manager, fe, ge, cube);
if (e == NULL) {
Cudd_IterDerefBdd(manager, t);
return(NULL);
}
if (t == e) {
r = t;
cuddDeref(t);
} else {
cuddRef(e);
if (Cudd_IsComplement(t)) {
r = cuddUniqueInter(manager, (int) index,
Cudd_Not(t), Cudd_Not(e));
if (r == NULL) {
Cudd_IterDerefBdd(manager, t);
Cudd_IterDerefBdd(manager, e);
return(NULL);
}
r = Cudd_Not(r);
} else {
r = cuddUniqueInter(manager,(int)index,t,e);
if (r == NULL) {
Cudd_IterDerefBdd(manager, t);
Cudd_IterDerefBdd(manager, e);
return(NULL);
}
}
cuddDeref(e);
cuddDeref(t);
}
}
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert(manager, DD_BDD_AND_ABSTRACT_TAG, f, g, cube, r);
return (r);
} /* end of cuddBddAndAbstractRecur */
/**Function********************************************************************
Synopsis [Implements the recursive step of Cudd_bddIntersect.]
Description []
SideEffects [None]
SeeAlso [Cudd_bddIntersect]
******************************************************************************/
DdNode *
cuddBddIntersectRecur(
DdManager * dd,
DdNode * f,
DdNode * g)
{
DdNode *res;
DdNode *F, *G, *t, *e;
DdNode *fv, *fnv, *gv, *gnv;
DdNode *one, *zero;
unsigned int index, topf, topg;
/* NuSMV: begin add */
abort(); /* NOT USED BY NUSMV */
/* NuSMV: begin end */
statLine(dd);
one = DD_TRUE(dd);
zero = Cudd_Not(one);
/* Terminal cases. */
if (f == zero || g == zero || f == Cudd_Not(g)) return(zero);
if (f == g || g == one) return(f);
if (f == one) return(g);
/* At this point f and g are not constant. */
if (f > g) { DdNode *tmp = f; f = g; g = tmp; }
res = cuddCacheLookup2(dd,Cudd_bddIntersect,f,g);
if (res != NULL) return(res);
/* Find splitting variable. Here we can skip the use of cuddI,
** because the operands are known to be non-constant.
*/
F = Cudd_Regular(f);
topf = dd->perm[F->index];
G = Cudd_Regular(g);
topg = dd->perm[G->index];
/* Compute cofactors. */
if (topf <= topg) {
index = F->index;
fv = cuddT(F);
fnv = cuddE(F);
if (Cudd_IsComplement(f)) {
fv = Cudd_Not(fv);
fnv = Cudd_Not(fnv);
}
} else {
index = G->index;
fv = fnv = f;
}
if (topg <= topf) {
gv = cuddT(G);
gnv = cuddE(G);
if (Cudd_IsComplement(g)) {
gv = Cudd_Not(gv);
gnv = Cudd_Not(gnv);
}
} else {
gv = gnv = g;
}
/* Compute partial results. */
t = cuddBddIntersectRecur(dd,fv,gv);
if (t == NULL) return(NULL);
cuddRef(t);
if (t != zero) {
e = zero;
} else {
e = cuddBddIntersectRecur(dd,fnv,gnv);
if (e == NULL) {
Cudd_IterDerefBdd(dd, t);
return(NULL);
}
}
cuddRef(e);
if (t == e) { /* both equal zero */
res = t;
} else if (Cudd_IsComplement(t)) {
res = cuddUniqueInter(dd,(int)index,Cudd_Not(t),Cudd_Not(e));
if (res == NULL) {
Cudd_IterDerefBdd(dd, t);
Cudd_IterDerefBdd(dd, e);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = cuddUniqueInter(dd,(int)index,t,e);
if (res == NULL) {
Cudd_IterDerefBdd(dd, t);
Cudd_IterDerefBdd(dd, e);
return(NULL);
}
}
cuddDeref(e);
cuddDeref(t);
cuddCacheInsert2(dd,Cudd_bddIntersect,f,g,res);
return(res);
} /* end of cuddBddIntersectRecur */
/**Function********************************************************************
Synopsis [Implements the recursive step of Cudd_bddAnd.]
Description [Implements the recursive step of Cudd_bddAnd by taking
the conjunction of two BDDs. Returns a pointer to the result is
successful; NULL otherwise.]
SideEffects [None]
SeeAlso [Cudd_bddAnd]
******************************************************************************/
DdNode *
cuddBddAndRecur(
DdManager * manager,
DdNode * f,
DdNode * g)
{
DdNode *F, *fv, *fnv, *G, *gv, *gnv;
DdNode *_true, *r, *t, *e;
unsigned int topf, topg, index;
statLine(manager);
_true = DD_TRUE(manager);
/* Terminal cases. */
F = Cudd_Regular(f);
G = Cudd_Regular(g);
if (F == G) {
if (f == g) return(f);
else return(Cudd_Not(_true));
}
if (F == _true) {
if (f == _true) return(g);
else return(f);
}
if (G == _true) {
if (g == _true) return(f);
else return(g);
}
/* At this point f and g are not constant. */
if (f > g) { /* Try to increase cache efficiency. */
DdNode *tmp = f;
f = g;
g = tmp;
F = Cudd_Regular(f);
G = Cudd_Regular(g);
}
/* Check cache. */
if (F->ref != 1 || G->ref != 1) {
r = cuddCacheLookup2(manager, Cudd_bddAnd, f, g);
if (r != NULL) return(r);
}
/* Here we can skip the use of cuddI, because the operands are known
** to be non-constant.
*/
topf = manager->perm[F->index];
topg = manager->perm[G->index];
/* Compute cofactors. */
if (topf <= topg) {
index = F->index;
fv = cuddT(F);
fnv = cuddE(F);
if (Cudd_IsComplement(f)) {
fv = Cudd_Not(fv);
fnv = Cudd_Not(fnv);
}
} else {
index = G->index;
fv = fnv = f;
}
if (topg <= topf) {
gv = cuddT(G);
gnv = cuddE(G);
if (Cudd_IsComplement(g)) {
gv = Cudd_Not(gv);
gnv = Cudd_Not(gnv);
}
} else {
gv = gnv = g;
}
t = cuddBddAndRecur(manager, fv, gv);
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddBddAndRecur(manager, fnv, gnv);
if (e == NULL) {
Cudd_IterDerefBdd(manager, t);
return(NULL);
}
cuddRef(e);
if (t == e) {
r = t;
} else {
if (Cudd_IsComplement(t)) {
r = cuddUniqueInter(manager,(int)index,Cudd_Not(t),Cudd_Not(e));
if (r == NULL) {
Cudd_IterDerefBdd(manager, t);
Cudd_IterDerefBdd(manager, e);
return(NULL);
}
r = Cudd_Not(r);
} else {
r = cuddUniqueInter(manager,(int)index,t,e);
if (r == NULL) {
Cudd_IterDerefBdd(manager, t);
Cudd_IterDerefBdd(manager, e);
return(NULL);
}
}
}
cuddDeref(e);
cuddDeref(t);
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert2(manager, Cudd_bddAnd, f, g, r);
return(r);
} /* end of cuddBddAndRecur */
/**Function********************************************************************
Synopsis [Determines whether f is less than or equal to g.]
Description [Returns 1 if f is less than or equal to g; 0 otherwise.
No new nodes are created.]
SideEffects [None]
SeeAlso [Cudd_bddIteConstant Cudd_addEvalConst]
******************************************************************************/
int
Cudd_bddLeq(
DdManager * dd,
DdNode * f,
DdNode * g)
{
DdNode *_true, *_false, *tmp, *F, *fv, *fvn, *gv, *gvn;
unsigned int topf, topg, res;
statLine(dd);
/* Terminal cases and normalization. */
if (f == g) return(1);
if (Cudd_IsComplement(g)) {
/* Special case: if f is regular and g is complemented,
** f(1,...,1) = 1 > 0 = g(1,...,1).
*/
if (!Cudd_IsComplement(f)) return(0);
/* Both are complemented: Swap and complement because
** f <= g <=> g' <= f' and we want the second argument to be regular.
*/
tmp = g;
g = Cudd_Not(f);
f = Cudd_Not(tmp);
} else if (Cudd_IsComplement(f) && g < f) {
tmp = g;
g = Cudd_Not(f);
f = Cudd_Not(tmp);
}
/* Now g is regular and, if f is not regular, f < g. */
_true = DD_TRUE(dd);
if (g == _true) return(1); /* no need to test against _false */
if (f == _true) return(0); /* since at this point g != _true */
if (Cudd_Not(f) == g) return(0); /* because neither is constant */
_false = Cudd_Not(_true);
if (f == _false) return(1);
/* Here neither f nor g is constant. */
/* Check cache. */
tmp = cuddCacheLookup2(dd,(DD_CTFP)Cudd_bddLeq,f,g);
if (tmp != NULL) {
return(tmp == _true);
}
/* Compute cofactors. */
F = Cudd_Regular(f);
topf = dd->perm[F->index];
topg = dd->perm[g->index];
if (topf <= topg) {
fv = cuddT(F); fvn = cuddE(F);
if (f != F) {
fv = Cudd_Not(fv);
fvn = Cudd_Not(fvn);
}
} else {
fv = fvn = f;
}
if (topg <= topf) {
gv = cuddT(g); gvn = cuddE(g);
} else {
gv = gvn = g;
}
/* Recursive calls. Since we want to maximize the probability of
** the special case f(1,...,1) > g(1,...,1), we consider the negative
** cofactors first. Indeed, the complementation parity of the positive
** cofactors is the same as the one of the parent functions.
*/
res = Cudd_bddLeq(dd,fvn,gvn) && Cudd_bddLeq(dd,fv,gv);
/* Store result in cache and return. */
cuddCacheInsert2(dd,(DD_CTFP)Cudd_bddLeq,f,g,(res ? _true : _false));
return(res);
} /* end of Cudd_bddLeq */
/**Function********************************************************************
Synopsis [Implements the recursive step of Cudd_bddIte.]
Description [Implements the recursive step of Cudd_bddIte. Returns a
pointer to the resulting BDD. NULL if the intermediate result blows
up or if reordering occurs.]
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddBddIteRecur(
DdManager * dd,
DdNode * f,
DdNode * g,
DdNode * h)
{
DdNode *_true, *_false, *res;
DdNode *r, *Fv, *Fnv, *Gv, *Gnv, *H, *Hv, *Hnv, *t, *e;
unsigned int topf, topg, toph, v;
int index = 0;
int comple;
statLine(dd);
/* Terminal cases. */
/* _True variable cases. */
if (f == (_true = DD_TRUE(dd))) /* ITE(TRUE,G,H) = G */
return(g);
if (f == (_false = Cudd_Not(_true))) /* ITE(FALSE,G,H) = H */
return(h);
/* From now on, f is known not to be a constant. */
if (g == _true || f == g) { /* ITE(F,F,H) = ITE(F,TRUE,H) = F + H */
if (h == _false) { /* ITE(F,TRUE,FALSE) = F */
return(f);
} else {
res = cuddBddAndRecur(dd,Cudd_Not(f),Cudd_Not(h));
return(Cudd_NotCond(res,res != NULL));
}
} else if (g == _false || f == Cudd_Not(g)) { /* ITE(F,!F,H) = ITE(F,FALSE,H) = !F * H */
if (h == _true) { /* ITE(F,FALSE,TRUE) = !F */
return(Cudd_Not(f));
} else {
res = cuddBddAndRecur(dd,Cudd_Not(f),h);
return(res);
}
}
if (h == _false || f == h) { /* ITE(F,G,F) = ITE(F,G,FALSE) = F * G */
res = cuddBddAndRecur(dd,f,g);
return(res);
} else if (h == _true || f == Cudd_Not(h)) { /* ITE(F,G,!F) = ITE(F,G,TRUE) = !F + G */
res = cuddBddAndRecur(dd,f,Cudd_Not(g));
return(Cudd_NotCond(res,res != NULL));
}
/* Check remaining _true variable case. */
if (g == h) { /* ITE(F,G,G) = G */
return(g);
} else if (g == Cudd_Not(h)) { /* ITE(F,G,!G) = F <-> G */
res = cuddBddXorRecur(dd,f,h);
return(res);
}
/* From here, there are no constants. */
comple = bddVarToCanonicalSimple(dd, &f, &g, &h, &topf, &topg, &toph);
/* f & g are now regular pointers */
v = ddMin(topg, toph);
/* A shortcut: ITE(F,G,H) = (v,G,H) if F = (v,TRUE,FALSE), v < top(G,H). */
if (topf < v && cuddT(f) == _true && cuddE(f) == _false) {
r = cuddUniqueInter(dd, (int) f->index, g, h);
return(Cudd_NotCond(r,comple && r != NULL));
}
/* Check cache. */
r = cuddCacheLookup(dd, DD_BDD_ITE_TAG, f, g, h);
if (r != NULL) {
return(Cudd_NotCond(r,comple));
}
/* Compute cofactors. */
if (topf <= v) {
v = ddMin(topf, v); /* v = top_var(F,G,H) */
index = f->index;
Fv = cuddT(f); Fnv = cuddE(f);
} else {
Fv = Fnv = f;
}
if (topg == v) {
index = g->index;
Gv = cuddT(g); Gnv = cuddE(g);
} else {
Gv = Gnv = g;
}
if (toph == v) {
H = Cudd_Regular(h);
index = H->index;
Hv = cuddT(H); Hnv = cuddE(H);
if (Cudd_IsComplement(h)) {
Hv = Cudd_Not(Hv);
Hnv = Cudd_Not(Hnv);
}
} else {
Hv = Hnv = h;
}
/* Recursive step. */
t = cuddBddIteRecur(dd,Fv,Gv,Hv);
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddBddIteRecur(dd,Fnv,Gnv,Hnv);
if (e == NULL) {
Cudd_IterDerefBdd(dd,t);
return(NULL);
}
cuddRef(e);
r = (t == e) ? t : cuddUniqueInter(dd,index,t,e);
if (r == NULL) {
Cudd_IterDerefBdd(dd,t);
Cudd_IterDerefBdd(dd,e);
return(NULL);
}
cuddDeref(t);
cuddDeref(e);
cuddCacheInsert(dd, DD_BDD_ITE_TAG, f, g, h, r);
return(Cudd_NotCond(r,comple));
} /* end of cuddBddIteRecur */
/**Function********************************************************************
Synopsis [Implements ITEconstant(f,g,h).]
Description [Implements ITEconstant(f,g,h). Returns a pointer to the
resulting BDD (which may or may not be constant) or DD_NON_CONSTANT.
No new nodes are created.]
SideEffects [None]
SeeAlso [Cudd_bddIte Cudd_bddIntersect Cudd_bddLeq Cudd_addIteConstant]
******************************************************************************/
DdNode *
Cudd_bddIteConstant(
DdManager * dd,
DdNode * f,
DdNode * g,
DdNode * h)
{
DdNode *r, *Fv, *Fnv, *Gv, *Gnv, *H, *Hv, *Hnv, *t, *e;
DdNode *one = DD_TRUE(dd);
DdNode *zero = Cudd_Not(one);
int comple;
unsigned int topf, topg, toph, v;
/* NuSMV: begin add */
abort(); /* NOT USED BY NUSMV */
/* NuSMV: begin end */
statLine(dd);
/* Trivial cases. */
if (f == one) /* ITE(TRUE,G,H) => G */
return(g);
if (f == zero) /* ITE(FALSE,G,H) => H */
return(h);
/* f now not a constant. */
bddVarToConst(f, &g, &h, one); /* possibly convert g or h */
/* to constants */
if (g == h) /* ITE(F,G,G) => G */
return(g);
if (Cudd_IsConstant(g) && Cudd_IsConstant(h))
return(DD_NON_CONSTANT); /* ITE(F,1,0) or ITE(F,0,1) */
/* => DD_NON_CONSTANT */
if (g == Cudd_Not(h))
return(DD_NON_CONSTANT); /* ITE(F,G,G') => DD_NON_CONSTANT */
/* if F != G and F != G' */
comple = bddVarToCanonical(dd, &f, &g, &h, &topf, &topg, &toph);
/* Cache lookup. */
r = cuddConstantLookup(dd, DD_BDD_ITE_CONSTANT_TAG, f, g, h);
if (r != NULL) {
return(Cudd_NotCond(r,comple && r != DD_NON_CONSTANT));
}
v = ddMin(topg, toph);
/* ITE(F,G,H) = (v,G,H) (non constant) if F = (v,1,0), v < top(G,H). */
if (topf < v && cuddT(f) == one && cuddE(f) == zero) {
return(DD_NON_CONSTANT);
}
/* Compute cofactors. */
if (topf <= v) {
v = ddMin(topf, v); /* v = top_var(F,G,H) */
Fv = cuddT(f); Fnv = cuddE(f);
} else {
Fv = Fnv = f;
}
if (topg == v) {
Gv = cuddT(g); Gnv = cuddE(g);
} else {
Gv = Gnv = g;
}
if (toph == v) {
H = Cudd_Regular(h);
Hv = cuddT(H); Hnv = cuddE(H);
if (Cudd_IsComplement(h)) {
Hv = Cudd_Not(Hv);
Hnv = Cudd_Not(Hnv);
}
} else {
Hv = Hnv = h;
}
/* Recursion. */
t = Cudd_bddIteConstant(dd, Fv, Gv, Hv);
if (t == DD_NON_CONSTANT || !Cudd_IsConstant(t)) {
cuddCacheInsert(dd, DD_BDD_ITE_CONSTANT_TAG, f, g, h, DD_NON_CONSTANT);
return(DD_NON_CONSTANT);
}
e = Cudd_bddIteConstant(dd, Fnv, Gnv, Hnv);
if (e == DD_NON_CONSTANT || !Cudd_IsConstant(e) || t != e) {
cuddCacheInsert(dd, DD_BDD_ITE_CONSTANT_TAG, f, g, h, DD_NON_CONSTANT);
return(DD_NON_CONSTANT);
}
cuddCacheInsert(dd, DD_BDD_ITE_CONSTANT_TAG, f, g, h, t);
return(Cudd_NotCond(t,comple));
} /* end of Cudd_bddIteConstant */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addOuterSum.]
Description [Performs the recursive step of Cudd_addOuterSum.
Returns a pointer to the result if successful; NULL otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static DdNode *
cuddAddOuterSumRecur(
DdManager *dd,
DdNode *M,
DdNode *r,
DdNode *c)
{
DdNode *P, *R, *Mt, *Me, *rt, *re, *ct, *ce, *Rt, *Re;
int topM, topc, topr;
int v, index;
statLine(dd);
/* Check special cases. */
if (r == DD_PLUS_INFINITY(dd) || c == DD_PLUS_INFINITY(dd)) return(M);
if (cuddIsConstant(c) && cuddIsConstant(r)) {
R = cuddUniqueConst(dd,Cudd_V(c)+Cudd_V(r));
cuddRef(R);
if (cuddIsConstant(M)) {
if (cuddV(R) <= cuddV(M)) {
cuddDeref(R);
return(R);
} else {
Cudd_RecursiveDeref(dd,R);
return(M);
}
} else {
P = Cudd_addApply(dd,Cudd_addMinimum,R,M);
cuddRef(P);
Cudd_RecursiveDeref(dd,R);
cuddDeref(P);
return(P);
}
}
/* Check the cache. */
R = cuddCacheLookup(dd,DD_ADD_OUT_SUM_TAG,M,r,c);
if (R != NULL) return(R);
topM = cuddI(dd,M->index); topr = cuddI(dd,r->index);
topc = cuddI(dd,c->index);
v = ddMin(topM,ddMin(topr,topc));
/* Compute cofactors. */
if (topM == v) { Mt = cuddT(M); Me = cuddE(M); } else { Mt = Me = M; }
if (topr == v) { rt = cuddT(r); re = cuddE(r); } else { rt = re = r; }
if (topc == v) { ct = cuddT(c); ce = cuddE(c); } else { ct = ce = c; }
/* Recursively solve. */
Rt = cuddAddOuterSumRecur(dd,Mt,rt,ct);
if (Rt == NULL) return(NULL);
cuddRef(Rt);
Re = cuddAddOuterSumRecur(dd,Me,re,ce);
if (Re == NULL) {
Cudd_RecursiveDeref(dd, Rt);
return(NULL);
}
cuddRef(Re);
index = dd->invperm[v];
R = (Rt == Re) ? Rt : cuddUniqueInter(dd,index,Rt,Re);
if (R == NULL) {
Cudd_RecursiveDeref(dd, Rt);
Cudd_RecursiveDeref(dd, Re);
return(NULL);
}
cuddDeref(Rt);
cuddDeref(Re);
/* Store the result in the cache. */
cuddCacheInsert(dd,DD_ADD_OUT_SUM_TAG,M,r,c,R);
return(R);
} /* end of cuddAddOuterSumRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addTriangle.]
Description [Performs the recursive step of Cudd_addTriangle. Returns
a pointer to the result if successful; NULL otherwise.]
SideEffects [None]
******************************************************************************/
static DdNode *
addTriangleRecur(
DdManager * dd,
DdNode * f,
DdNode * g,
int * vars,
DdNode *cube)
{
DdNode *fv, *fvn, *gv, *gvn, *t, *e, *res;
CUDD_VALUE_TYPE value;
int top, topf, topg, index;
statLine(dd);
if (f == DD_PLUS_INFINITY(dd) || g == DD_PLUS_INFINITY(dd)) {
return(DD_PLUS_INFINITY(dd));
}
if (cuddIsConstant(f) && cuddIsConstant(g)) {
value = cuddV(f) + cuddV(g);
res = cuddUniqueConst(dd, value);
return(res);
}
if (f < g) {
DdNode *tmp = f;
f = g;
g = tmp;
}
if (f->ref != 1 || g->ref != 1) {
res = cuddCacheLookup(dd, DD_ADD_TRIANGLE_TAG, f, g, cube);
if (res != NULL) {
return(res);
}
}
topf = cuddI(dd,f->index); topg = cuddI(dd,g->index);
top = ddMin(topf,topg);
if (top == topf) {fv = cuddT(f); fvn = cuddE(f);} else {fv = fvn = f;}
if (top == topg) {gv = cuddT(g); gvn = cuddE(g);} else {gv = gvn = g;}
t = addTriangleRecur(dd, fv, gv, vars, cube);
if (t == NULL) return(NULL);
cuddRef(t);
e = addTriangleRecur(dd, fvn, gvn, vars, cube);
if (e == NULL) {
Cudd_RecursiveDeref(dd, t);
return(NULL);
}
cuddRef(e);
index = dd->invperm[top];
if (vars[index] < 0) {
res = (t == e) ? t : cuddUniqueInter(dd,index,t,e);
if (res == NULL) {
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
return(NULL);
}
cuddDeref(t);
cuddDeref(e);
} else {
res = cuddAddApplyRecur(dd,Cudd_addMinimum,t,e);
if (res == NULL) {
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, t);
Cudd_RecursiveDeref(dd, e);
cuddDeref(res);
}
if (f->ref != 1 || g->ref != 1) {
cuddCacheInsert(dd, DD_ADD_TRIANGLE_TAG, f, g, cube, res);
}
return(res);
} /* end of addTriangleRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddPortToBdd.]
Description []
SideEffects [None]
SeeAlso []
******************************************************************************/
static DdNode *
zddPortToBddStep(
DdManager * dd /* manager */,
DdNode * f /* ZDD to be converted */,
int depth /* recursion depth */)
{
DdNode *one, *zero, *T, *E, *res, *var;
unsigned int index;
unsigned int level;
statLine(dd);
one = DD_ONE(dd);
zero = DD_ZERO(dd);
if (f == zero) return(Cudd_Not(one));
if (depth == dd->sizeZ) return(one);
index = dd->invpermZ[depth];
level = cuddIZ(dd,f->index);
var = cuddUniqueInter(dd,index,one,Cudd_Not(one));
if (var == NULL) return(NULL);
cuddRef(var);
if (level > (unsigned) depth) {
E = zddPortToBddStep(dd,f,depth+1);
if (E == NULL) {
Cudd_RecursiveDeref(dd,var);
return(NULL);
}
cuddRef(E);
res = cuddBddIteRecur(dd,var,Cudd_Not(one),E);
if (res == NULL) {
Cudd_RecursiveDeref(dd,var);
Cudd_RecursiveDeref(dd,E);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd,var);
Cudd_RecursiveDeref(dd,E);
cuddDeref(res);
return(res);
}
res = cuddCacheLookup1(dd,Cudd_zddPortToBdd,f);
if (res != NULL) {
Cudd_RecursiveDeref(dd,var);
return(res);
}
T = zddPortToBddStep(dd,cuddT(f),depth+1);
if (T == NULL) {
Cudd_RecursiveDeref(dd,var);
return(NULL);
}
cuddRef(T);
E = zddPortToBddStep(dd,cuddE(f),depth+1);
if (E == NULL) {
Cudd_RecursiveDeref(dd,var);
Cudd_RecursiveDeref(dd,T);
return(NULL);
}
cuddRef(E);
res = cuddBddIteRecur(dd,var,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd,var);
Cudd_RecursiveDeref(dd,T);
Cudd_RecursiveDeref(dd,E);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd,var);
Cudd_RecursiveDeref(dd,T);
Cudd_RecursiveDeref(dd,E);
cuddDeref(res);
cuddCacheInsert1(dd,Cudd_zddPortToBdd,f,res);
return(res);
} /* end of zddPortToBddStep */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddDivideF.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddDivideF]
******************************************************************************/
DdNode *
cuddZddDivideF(
DdManager * dd,
DdNode * f,
DdNode * g)
{
int v;
DdNode *one = DD_ONE(dd);
DdNode *zero = DD_ZERO(dd);
DdNode *f0, *f1, *g0, *g1;
DdNode *q, *r, *tmp;
int flag;
statLine(dd);
if (g == one)
return(f);
if (f == zero || f == one)
return(zero);
if (f == g)
return(one);
/* Check cache. */
r = cuddCacheLookup2Zdd(dd, cuddZddDivideF, f, g);
if (r)
return(r);
v = g->index;
flag = cuddZddGetCofactors2(dd, f, v, &f1, &f0);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
flag = cuddZddGetCofactors2(dd, g, v, &g1, &g0); /* g1 != zero */
if (flag == 1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
return(NULL);
}
Cudd_Ref(g1);
Cudd_Ref(g0);
r = cuddZddDivideF(dd, f1, g1);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
return(NULL);
}
Cudd_Ref(r);
if (r != zero && g0 != zero) {
tmp = r;
q = cuddZddDivideF(dd, f0, g0);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
return(NULL);
}
Cudd_Ref(q);
r = cuddZddIntersect(dd, r, q);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, q);
return(NULL);
}
Cudd_Ref(r);
Cudd_RecursiveDerefZdd(dd, q);
Cudd_RecursiveDerefZdd(dd, tmp);
}
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
cuddCacheInsert2(dd, cuddZddDivideF, f, g, r);
Cudd_Deref(r);
return(r);
} /* end of cuddZddDivideF */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddIte.]
Description []
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddZddIte(
DdManager * dd,
DdNode * f,
DdNode * g,
DdNode * h)
{
DdNode *tautology, *empty;
DdNode *r,*Gv,*Gvn,*Hv,*Hvn,*t,*e;
unsigned int topf,topg,toph,v,top;
int index;
statLine(dd);
/* Trivial cases. */
/* One variable cases. */
if (f == (empty = DD_ZERO(dd))) { /* ITE(0,G,H) = H */
return(h);
}
topf = cuddIZ(dd,f->index);
topg = cuddIZ(dd,g->index);
toph = cuddIZ(dd,h->index);
v = ddMin(topg,toph);
top = ddMin(topf,v);
tautology = (top == CUDD_MAXINDEX) ? DD_ONE(dd) : dd->univ[top];
if (f == tautology) { /* ITE(1,G,H) = G */
return(g);
}
/* From now on, f is known to not be a constant. */
zddVarToConst(f,&g,&h,tautology,empty);
/* Check remaining one variable cases. */
if (g == h) { /* ITE(F,G,G) = G */
return(g);
}
if (g == tautology) { /* ITE(F,1,0) = F */
if (h == empty) return(f);
}
/* Check cache. */
r = cuddCacheLookupZdd(dd,DD_ZDD_ITE_TAG,f,g,h);
if (r != NULL) {
return(r);
}
/* Recompute these because they may have changed in zddVarToConst. */
topg = cuddIZ(dd,g->index);
toph = cuddIZ(dd,h->index);
v = ddMin(topg,toph);
if (topf < v) {
r = cuddZddIte(dd,cuddE(f),g,h);
if (r == NULL) return(NULL);
} else if (topf > v) {
if (topg > v) {
Gvn = g;
index = h->index;
} else {
Gvn = cuddE(g);
index = g->index;
}
if (toph > v) {
Hv = empty; Hvn = h;
} else {
Hv = cuddT(h); Hvn = cuddE(h);
}
e = cuddZddIte(dd,f,Gvn,Hvn);
if (e == NULL) return(NULL);
cuddRef(e);
r = cuddZddGetNode(dd,index,Hv,e);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd,e);
return(NULL);
}
cuddDeref(e);
} else {
index = f->index;
if (topg > v) {
Gv = empty; Gvn = g;
} else {
Gv = cuddT(g); Gvn = cuddE(g);
}
if (toph > v) {
Hv = empty; Hvn = h;
} else {
Hv = cuddT(h); Hvn = cuddE(h);
}
e = cuddZddIte(dd,cuddE(f),Gvn,Hvn);
if (e == NULL) return(NULL);
cuddRef(e);
t = cuddZddIte(dd,cuddT(f),Gv,Hv);
if (t == NULL) {
Cudd_RecursiveDerefZdd(dd,e);
return(NULL);
}
cuddRef(t);
r = cuddZddGetNode(dd,index,t,e);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd,e);
Cudd_RecursiveDerefZdd(dd,t);
return(NULL);
}
cuddDeref(t);
cuddDeref(e);
}
cuddCacheInsert(dd,DD_ZDD_ITE_TAG,f,g,h,r);
return(r);
} /* end of cuddZddIte */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddProduct.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddProduct]
******************************************************************************/
DdNode *
cuddZddProduct(
DdManager * dd,
DdNode * f,
DdNode * g)
{
int v, top_f, top_g;
DdNode *tmp, *term1, *term2, *term3;
DdNode *f0, *f1, *fd, *g0, *g1, *gd;
DdNode *R0, *R1, *Rd, *N0, *N1;
DdNode *r;
DdNode *one = DD_ONE(dd);
DdNode *zero = DD_ZERO(dd);
int flag;
int pv, nv;
statLine(dd);
if (f == zero || g == zero)
return(zero);
if (f == one)
return(g);
if (g == one)
return(f);
top_f = dd->permZ[f->index];
top_g = dd->permZ[g->index];
if (top_f > top_g)
return(cuddZddProduct(dd, g, f));
/* Check cache */
r = cuddCacheLookup2Zdd(dd, cuddZddProduct, f, g);
if (r)
return(r);
v = f->index; /* either yi or zi */
flag = cuddZddGetCofactors3(dd, f, v, &f1, &f0, &fd);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
Cudd_Ref(fd);
flag = cuddZddGetCofactors3(dd, g, v, &g1, &g0, &gd);
if (flag == 1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
return(NULL);
}
Cudd_Ref(g1);
Cudd_Ref(g0);
Cudd_Ref(gd);
pv = cuddZddGetPosVarIndex(dd, v);
nv = cuddZddGetNegVarIndex(dd, v);
Rd = cuddZddProduct(dd, fd, gd);
if (Rd == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(Rd);
term1 = cuddZddProduct(dd, f0, g0);
if (term1 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
return(NULL);
}
Cudd_Ref(term1);
term2 = cuddZddProduct(dd, f0, gd);
if (term2 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
Cudd_RecursiveDerefZdd(dd, term1);
return(NULL);
}
Cudd_Ref(term2);
term3 = cuddZddProduct(dd, fd, g0);
if (term3 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
return(NULL);
}
Cudd_Ref(term3);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g0);
tmp = cuddZddUnion(dd, term1, term2);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
Cudd_RecursiveDerefZdd(dd, term3);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
R0 = cuddZddUnion(dd, tmp, term3);
if (R0 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
Cudd_RecursiveDerefZdd(dd, term3);
Cudd_RecursiveDerefZdd(dd, tmp);
return(NULL);
}
Cudd_Ref(R0);
Cudd_RecursiveDerefZdd(dd, tmp);
Cudd_RecursiveDerefZdd(dd, term3);
N0 = cuddZddGetNode(dd, nv, R0, Rd); /* nv = zi */
if (N0 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, Rd);
Cudd_RecursiveDerefZdd(dd, R0);
return(NULL);
}
Cudd_Ref(N0);
Cudd_RecursiveDerefZdd(dd, R0);
Cudd_RecursiveDerefZdd(dd, Rd);
term1 = cuddZddProduct(dd, f1, g1);
if (term1 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, N0);
return(NULL);
}
Cudd_Ref(term1);
term2 = cuddZddProduct(dd, f1, gd);
if (term2 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, N0);
Cudd_RecursiveDerefZdd(dd, term1);
return(NULL);
}
Cudd_Ref(term2);
term3 = cuddZddProduct(dd, fd, g1);
if (term3 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, gd);
Cudd_RecursiveDerefZdd(dd, N0);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
return(NULL);
}
Cudd_Ref(term3);
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
tmp = cuddZddUnion(dd, term1, term2);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, N0);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
Cudd_RecursiveDerefZdd(dd, term3);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
R1 = cuddZddUnion(dd, tmp, term3);
if (R1 == NULL) {
Cudd_RecursiveDerefZdd(dd, N0);
Cudd_RecursiveDerefZdd(dd, term3);
Cudd_RecursiveDerefZdd(dd, tmp);
return(NULL);
}
Cudd_Ref(R1);
Cudd_RecursiveDerefZdd(dd, tmp);
Cudd_RecursiveDerefZdd(dd, term3);
N1 = cuddZddGetNode(dd, pv, R1, N0); /* pv = yi */
if (N1 == NULL) {
Cudd_RecursiveDerefZdd(dd, N0);
Cudd_RecursiveDerefZdd(dd, R1);
return(NULL);
}
Cudd_Ref(N1);
Cudd_RecursiveDerefZdd(dd, R1);
Cudd_RecursiveDerefZdd(dd, N0);
cuddCacheInsert2(dd, cuddZddProduct, f, g, N1);
Cudd_Deref(N1);
return(N1);
} /* end of cuddZddProduct */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_Cofactor.]
Description [Performs the recursive step of Cudd_Cofactor. Returns a
pointer to the cofactor if successful; NULL otherwise.]
SideEffects [None]
SeeAlso [Cudd_Cofactor]
******************************************************************************/
DdNode *
cuddCofactorRecur(
DdManager * dd,
DdNode * f,
DdNode * g)
{
DdNode *one,*zero,*F,*G,*g1,*g0,*f1,*f0,*t,*e,*r;
unsigned int topf,topg;
int comple;
statLine(dd);
F = Cudd_Regular(f);
if (cuddIsConstant(F)) return(f);
one = DD_ONE(dd);
/* The invariant g != 0 is true on entry to this procedure and is
** recursively maintained by it. Therefore it suffices to test g
** against one to make sure it is not constant.
*/
if (g == one) return(f);
/* From now on, f and g are known not to be constants. */
comple = f != F;
r = cuddCacheLookup2(dd,Cudd_Cofactor,F,g);
if (r != NULL) {
return(Cudd_NotCond(r,comple));
}
topf = dd->perm[F->index];
G = Cudd_Regular(g);
topg = dd->perm[G->index];
/* We take the cofactors of F because we are going to rely on
** the fact that the cofactors of the complement are the complements
** of the cofactors to better utilize the cache. Variable comple
** remembers whether we have to complement the result or not.
*/
if (topf <= topg) {
f1 = cuddT(F); f0 = cuddE(F);
} else {
f1 = f0 = F;
}
if (topg <= topf) {
g1 = cuddT(G); g0 = cuddE(G);
if (g != G) { g1 = Cudd_Not(g1); g0 = Cudd_Not(g0); }
} else {
g1 = g0 = g;
}
zero = Cudd_Not(one);
if (topf >= topg) {
if (g0 == zero || g0 == DD_ZERO(dd)) {
r = cuddCofactorRecur(dd, f1, g1);
} else if (g1 == zero || g1 == DD_ZERO(dd)) {
r = cuddCofactorRecur(dd, f0, g0);
} else {
(void) fprintf(dd->out,
"Cudd_Cofactor: Invalid restriction 2\n");
dd->errorCode = CUDD_INVALID_ARG;
return(NULL);
}
if (r == NULL) return(NULL);
} else /* if (topf < topg) */ {
t = cuddCofactorRecur(dd, f1, g);
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddCofactorRecur(dd, f0, g);
if (e == NULL) {
Cudd_RecursiveDeref(dd, t);
return(NULL);
}
cuddRef(e);
if (t == e) {
r = t;
} else if (Cudd_IsComplement(t)) {
r = cuddUniqueInter(dd,(int)F->index,Cudd_Not(t),Cudd_Not(e));
if (r != NULL)
r = Cudd_Not(r);
} else {
r = cuddUniqueInter(dd,(int)F->index,t,e);
}
if (r == NULL) {
Cudd_RecursiveDeref(dd ,e);
Cudd_RecursiveDeref(dd ,t);
return(NULL);
}
cuddDeref(t);
cuddDeref(e);
}
cuddCacheInsert2(dd,Cudd_Cofactor,F,g,r);
return(Cudd_NotCond(r,comple));
} /* end of cuddCofactorRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddUnateProduct.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddUnateProduct]
******************************************************************************/
DdNode *
cuddZddUnateProduct(
DdManager * dd,
DdNode * f,
DdNode * g)
{
int v, top_f, top_g;
DdNode *term1, *term2, *term3, *term4;
DdNode *sum1, *sum2;
DdNode *f0, *f1, *g0, *g1;
DdNode *r;
DdNode *one = DD_ONE(dd);
DdNode *zero = DD_ZERO(dd);
int flag;
statLine(dd);
if (f == zero || g == zero)
return(zero);
if (f == one)
return(g);
if (g == one)
return(f);
top_f = dd->permZ[f->index];
top_g = dd->permZ[g->index];
if (top_f > top_g)
return(cuddZddUnateProduct(dd, g, f));
/* Check cache */
r = cuddCacheLookup2Zdd(dd, cuddZddUnateProduct, f, g);
if (r)
return(r);
v = f->index; /* either yi or zi */
flag = cuddZddGetCofactors2(dd, f, v, &f1, &f0);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
flag = cuddZddGetCofactors2(dd, g, v, &g1, &g0);
if (flag == 1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
return(NULL);
}
Cudd_Ref(g1);
Cudd_Ref(g0);
term1 = cuddZddUnateProduct(dd, f1, g1);
if (term1 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
return(NULL);
}
Cudd_Ref(term1);
term2 = cuddZddUnateProduct(dd, f1, g0);
if (term2 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, term1);
return(NULL);
}
Cudd_Ref(term2);
term3 = cuddZddUnateProduct(dd, f0, g1);
if (term3 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
return(NULL);
}
Cudd_Ref(term3);
term4 = cuddZddUnateProduct(dd, f0, g0);
if (term4 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
Cudd_RecursiveDerefZdd(dd, term3);
return(NULL);
}
Cudd_Ref(term4);
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
sum1 = cuddZddUnion(dd, term1, term2);
if (sum1 == NULL) {
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
Cudd_RecursiveDerefZdd(dd, term3);
Cudd_RecursiveDerefZdd(dd, term4);
return(NULL);
}
Cudd_Ref(sum1);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term2);
sum2 = cuddZddUnion(dd, sum1, term3);
if (sum2 == NULL) {
Cudd_RecursiveDerefZdd(dd, term3);
Cudd_RecursiveDerefZdd(dd, term4);
Cudd_RecursiveDerefZdd(dd, sum1);
return(NULL);
}
Cudd_Ref(sum2);
Cudd_RecursiveDerefZdd(dd, sum1);
Cudd_RecursiveDerefZdd(dd, term3);
r = cuddZddGetNode(dd, v, sum2, term4);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd, term4);
Cudd_RecursiveDerefZdd(dd, sum2);
return(NULL);
}
Cudd_Ref(r);
Cudd_RecursiveDerefZdd(dd, sum2);
Cudd_RecursiveDerefZdd(dd, term4);
cuddCacheInsert2(dd, cuddZddUnateProduct, f, g, r);
Cudd_Deref(r);
return(r);
} /* end of cuddZddUnateProduct */
/**Function********************************************************************
Synopsis [Implements the recursive step of Cudd_bddClippingAnd.]
Description [Implements the recursive step of Cudd_bddClippingAnd by taking
the conjunction of two BDDs. Returns a pointer to the result is
successful; NULL otherwise.]
SideEffects [None]
SeeAlso [cuddBddClippingAnd]
******************************************************************************/
static DdNode *
cuddBddClippingAndRecur(
DdManager * manager,
DdNode * f,
DdNode * g,
int distance,
int direction)
{
DdNode *F, *ft, *fe, *G, *gt, *ge;
DdNode *one, *zero, *r, *t, *e;
unsigned int topf, topg, index;
DD_CTFP cacheOp;
statLine(manager);
one = DD_ONE(manager);
zero = Cudd_Not(one);
/* Terminal cases. */
if (f == zero || g == zero || f == Cudd_Not(g)) return(zero);
if (f == g || g == one) return(f);
if (f == one) return(g);
if (distance == 0) {
/* One last attempt at returning the right result. We sort of
** cheat by calling Cudd_bddLeq. */
if (Cudd_bddLeq(manager,f,g)) return(f);
if (Cudd_bddLeq(manager,g,f)) return(g);
if (direction == 1) {
if (Cudd_bddLeq(manager,f,Cudd_Not(g)) ||
Cudd_bddLeq(manager,g,Cudd_Not(f))) return(zero);
}
return(Cudd_NotCond(one,(direction == 0)));
}
/* At this point f and g are not constant. */
distance--;
/* Check cache. Try to increase cache efficiency by sorting the
** pointers. */
if (f > g) {
DdNode *tmp = f;
f = g; g = tmp;
}
F = Cudd_Regular(f);
G = Cudd_Regular(g);
cacheOp = (DD_CTFP)
(direction ? Cudd_bddClippingAnd : cuddBddClippingAnd);
if (F->ref != 1 || G->ref != 1) {
r = cuddCacheLookup2(manager, cacheOp, f, g);
if (r != NULL) return(r);
}
/* Here we can skip the use of cuddI, because the operands are known
** to be non-constant.
*/
topf = manager->perm[F->index];
topg = manager->perm[G->index];
/* Compute cofactors. */
if (topf <= topg) {
index = F->index;
ft = cuddT(F);
fe = cuddE(F);
if (Cudd_IsComplement(f)) {
ft = Cudd_Not(ft);
fe = Cudd_Not(fe);
}
} else {
index = G->index;
ft = fe = f;
}
if (topg <= topf) {
gt = cuddT(G);
ge = cuddE(G);
if (Cudd_IsComplement(g)) {
gt = Cudd_Not(gt);
ge = Cudd_Not(ge);
}
} else {
gt = ge = g;
}
t = cuddBddClippingAndRecur(manager, ft, gt, distance, direction);
if (t == NULL) return(NULL);
cuddRef(t);
e = cuddBddClippingAndRecur(manager, fe, ge, distance, direction);
if (e == NULL) {
Cudd_RecursiveDeref(manager, t);
return(NULL);
}
cuddRef(e);
if (t == e) {
r = t;
} else {
if (Cudd_IsComplement(t)) {
r = cuddUniqueInter(manager,(int)index,Cudd_Not(t),Cudd_Not(e));
if (r == NULL) {
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
return(NULL);
}
r = Cudd_Not(r);
} else {
r = cuddUniqueInter(manager,(int)index,t,e);
if (r == NULL) {
Cudd_RecursiveDeref(manager, t);
Cudd_RecursiveDeref(manager, e);
return(NULL);
}
}
}
cuddDeref(e);
cuddDeref(t);
if (F->ref != 1 || G->ref != 1)
cuddCacheInsert2(manager, cacheOp, f, g, r);
return(r);
} /* end of cuddBddClippingAndRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddWeakDiv.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddWeakDiv]
******************************************************************************/
DdNode *
cuddZddWeakDiv(
DdManager * dd,
DdNode * f,
DdNode * g)
{
int v;
DdNode *one = DD_ONE(dd);
DdNode *zero = DD_ZERO(dd);
DdNode *f0, *f1, *fd, *g0, *g1, *gd;
DdNode *q, *tmp;
DdNode *r;
int flag;
statLine(dd);
if (g == one)
return(f);
if (f == zero || f == one)
return(zero);
if (f == g)
return(one);
/* Check cache. */
r = cuddCacheLookup2Zdd(dd, cuddZddWeakDiv, f, g);
if (r)
return(r);
v = g->index;
flag = cuddZddGetCofactors3(dd, f, v, &f1, &f0, &fd);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
Cudd_Ref(fd);
flag = cuddZddGetCofactors3(dd, g, v, &g1, &g0, &gd);
if (flag == 1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
return(NULL);
}
Cudd_Ref(g1);
Cudd_Ref(g0);
Cudd_Ref(gd);
q = g;
if (g0 != zero) {
q = cuddZddWeakDiv(dd, f0, g0);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(q);
}
else
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g0);
if (q == zero) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
cuddCacheInsert2(dd, cuddZddWeakDiv, f, g, zero);
Cudd_Deref(q);
return(zero);
}
if (g1 != zero) {
Cudd_RecursiveDerefZdd(dd, q);
tmp = cuddZddWeakDiv(dd, f1, g1);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
if (q == g)
q = tmp;
else {
q = cuddZddIntersect(dd, q, tmp);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, tmp);
}
}
else {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
}
if (q == zero) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
cuddCacheInsert2(dd, cuddZddWeakDiv, f, g, zero);
Cudd_Deref(q);
return(zero);
}
if (gd != zero) {
Cudd_RecursiveDerefZdd(dd, q);
tmp = cuddZddWeakDiv(dd, fd, gd);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
if (q == g)
q = tmp;
else {
q = cuddZddIntersect(dd, q, tmp);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, tmp);
return(NULL);
}
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, tmp);
}
}
else {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
}
cuddCacheInsert2(dd, cuddZddWeakDiv, f, g, q);
Cudd_Deref(q);
return(q);
} /* end of cuddZddWeakDiv */
/**Function********************************************************************
Synopsis [Implements the recursive step of Cudd_SplitSet.]
Description [Implements the recursive step of Cudd_SplitSet. The
procedure recursively traverses the BDD and checks to see if any
node satisfies the minterm requirements as specified by 'n'. At any
node X, n is compared to the number of minterms in the onset of X's
children. If either of the child nodes have exactly n minterms, then
that node is returned; else, if n is greater than the onset of one
of the child nodes, that node is retained and the difference in the
number of minterms is extracted from the other child. In case n
minterms can be extracted from constant 1, the algorithm returns the
result with at most log(n) nodes.]
SideEffects [The array 'varSeen' is updated at every recursive call
to set the variables traversed by the procedure.]
SeeAlso []
******************************************************************************/
DdNode*
cuddSplitSetRecur(
DdManager * manager,
st_table * mtable,
int * varSeen,
DdNode * p,
double n,
double max,
int index)
{
DdNode *one, *zero, *N, *Nv;
DdNode *Nnv, *q, *r, *v;
DdNode *result;
double *dummy, numT, numE;
int variable, positive;
statLine(manager);
one = DD_ONE(manager);
zero = Cudd_Not(one);
/* If p is constant, extract n minterms from constant 1. The procedure by
** construction guarantees that minterms will not be extracted from
** constant 0.
*/
if (Cudd_IsConstant(p)) {
q = selectMintermsFromUniverse(manager,varSeen,n);
return(q);
}
N = Cudd_Regular(p);
/* Set variable as seen. */
variable = N->index;
varSeen[manager->invperm[variable]] = -1;
Nv = cuddT(N);
Nnv = cuddE(N);
if (Cudd_IsComplement(p)) {
Nv = Cudd_Not(Nv);
Nnv = Cudd_Not(Nnv);
}
/* If both the children of 'p' are constants, extract n minterms from a
** constant node.
*/
if (Cudd_IsConstant(Nv) && Cudd_IsConstant(Nnv)) {
q = selectMintermsFromUniverse(manager,varSeen,n);
if (q == NULL) {
return(NULL);
}
cuddRef(q);
r = cuddBddAndRecur(manager,p,q);
if (r == NULL) {
Cudd_RecursiveDeref(manager,q);
return(NULL);
}
cuddRef(r);
Cudd_RecursiveDeref(manager,q);
cuddDeref(r);
return(r);
}
/* Lookup the # of minterms in the onset of the node from the table. */
if (!Cudd_IsConstant(Nv)) {
st_lookup(mtable,(char *)Nv, (char **)&dummy);
numT = *dummy/(2*(1<<index));
} else if (Nv == one) {
numT = max/(2*(1<<index));
} else {
numT = 0;
}
if (!Cudd_IsConstant(Nnv)) {
st_lookup(mtable,(char *)Nnv, (char **)&dummy);
numE = *dummy/(2*(1<<index));
} else if (Nnv == one) {
numE = max/(2*(1<<index));
} else {
numE = 0;
}
v = cuddUniqueInter(manager,variable,one,zero);
cuddRef(v);
/* If perfect match. */
if (numT == n) {
q = cuddBddAndRecur(manager,v,Nv);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(q);
return(q);
}
if (numE == n) {
q = cuddBddAndRecur(manager,Cudd_Not(v),Nnv);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(q);
return(q);
}
/* If n is greater than numT, extract the difference from the ELSE child
** and retain the function represented by the THEN branch.
*/
if (numT < n) {
q = cuddSplitSetRecur(manager,mtable,varSeen,
Nnv,(n-numT),max,index+1);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
r = cuddBddIteRecur(manager,v,Nv,q);
if (r == NULL) {
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(r);
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(r);
return(r);
}
/* If n is greater than numE, extract the difference from the THEN child
** and retain the function represented by the ELSE branch.
*/
if (numE < n) {
q = cuddSplitSetRecur(manager,mtable,varSeen,
Nv, (n-numE),max,index+1);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
r = cuddBddIteRecur(manager,v,q,Nnv);
if (r == NULL) {
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(r);
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(r);
return(r);
}
/* None of the above cases; (n < numT and n < numE) and either of
** the Nv, Nnv or both are not constants. If possible extract the
** required minterms the constant branch.
*/
if (Cudd_IsConstant(Nv) && !Cudd_IsConstant(Nnv)) {
q = selectMintermsFromUniverse(manager,varSeen,n);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
result = cuddBddAndRecur(manager,v,q);
if (result == NULL) {
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(result);
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(result);
return(result);
} else if (!Cudd_IsConstant(Nv) && Cudd_IsConstant(Nnv)) {
q = selectMintermsFromUniverse(manager,varSeen,n);
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
result = cuddBddAndRecur(manager,Cudd_Not(v),q);
if (result == NULL) {
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(result);
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(result);
return(result);
}
/* Both Nv and Nnv are not constants. So choose the one which
** has fewer minterms in its onset.
*/
positive = 0;
if (numT < numE) {
q = cuddSplitSetRecur(manager,mtable,varSeen,
Nv,n,max,index+1);
positive = 1;
} else {
q = cuddSplitSetRecur(manager,mtable,varSeen,
Nnv,n,max,index+1);
}
if (q == NULL) {
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(q);
if (positive) {
result = cuddBddAndRecur(manager,v,q);
} else {
result = cuddBddAndRecur(manager,Cudd_Not(v),q);
}
if (result == NULL) {
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
return(NULL);
}
cuddRef(result);
Cudd_RecursiveDeref(manager,q);
Cudd_RecursiveDeref(manager,v);
cuddDeref(result);
return(result);
} /* end of cuddSplitSetRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddWeakDivF.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddWeakDivF]
******************************************************************************/
DdNode *
cuddZddWeakDivF(
DdManager * dd,
DdNode * f,
DdNode * g)
{
int v, top_f, top_g, vf, vg;
DdNode *one = DD_ONE(dd);
DdNode *zero = DD_ZERO(dd);
DdNode *f0, *f1, *fd, *g0, *g1, *gd;
DdNode *q, *tmp;
DdNode *r;
DdNode *term1, *term0, *termd;
int flag;
int pv, nv;
statLine(dd);
if (g == one)
return(f);
if (f == zero || f == one)
return(zero);
if (f == g)
return(one);
/* Check cache. */
r = cuddCacheLookup2Zdd(dd, cuddZddWeakDivF, f, g);
if (r)
return(r);
top_f = dd->permZ[f->index];
top_g = dd->permZ[g->index];
vf = top_f >> 1;
vg = top_g >> 1;
v = ddMin(top_f, top_g);
if (v == top_f && vf < vg) {
v = f->index;
flag = cuddZddGetCofactors3(dd, f, v, &f1, &f0, &fd);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
Cudd_Ref(fd);
pv = cuddZddGetPosVarIndex(dd, v);
nv = cuddZddGetNegVarIndex(dd, v);
term1 = cuddZddWeakDivF(dd, f1, g);
if (term1 == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
return(NULL);
}
Cudd_Ref(term1);
Cudd_RecursiveDerefZdd(dd, f1);
term0 = cuddZddWeakDivF(dd, f0, g);
if (term0 == NULL) {
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, term1);
return(NULL);
}
Cudd_Ref(term0);
Cudd_RecursiveDerefZdd(dd, f0);
termd = cuddZddWeakDivF(dd, fd, g);
if (termd == NULL) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term0);
return(NULL);
}
Cudd_Ref(termd);
Cudd_RecursiveDerefZdd(dd, fd);
tmp = cuddZddGetNode(dd, nv, term0, termd); /* nv = zi */
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, term0);
Cudd_RecursiveDerefZdd(dd, termd);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, term0);
Cudd_RecursiveDerefZdd(dd, termd);
q = cuddZddGetNode(dd, pv, term1, tmp); /* pv = yi */
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, tmp);
return(NULL);
}
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, term1);
Cudd_RecursiveDerefZdd(dd, tmp);
cuddCacheInsert2(dd, cuddZddWeakDivF, f, g, q);
Cudd_Deref(q);
return(q);
}
if (v == top_f)
v = f->index;
else
v = g->index;
flag = cuddZddGetCofactors3(dd, f, v, &f1, &f0, &fd);
if (flag == 1)
return(NULL);
Cudd_Ref(f1);
Cudd_Ref(f0);
Cudd_Ref(fd);
flag = cuddZddGetCofactors3(dd, g, v, &g1, &g0, &gd);
if (flag == 1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
return(NULL);
}
Cudd_Ref(g1);
Cudd_Ref(g0);
Cudd_Ref(gd);
q = g;
if (g0 != zero) {
q = cuddZddWeakDivF(dd, f0, g0);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, g0);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(q);
}
else
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, g0);
if (q == zero) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
cuddCacheInsert2(dd, cuddZddWeakDivF, f, g, zero);
Cudd_Deref(q);
return(zero);
}
if (g1 != zero) {
Cudd_RecursiveDerefZdd(dd, q);
tmp = cuddZddWeakDivF(dd, f1, g1);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
if (q == g)
q = tmp;
else {
q = cuddZddIntersect(dd, q, tmp);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, tmp);
}
}
else {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, g1);
}
if (q == zero) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
cuddCacheInsert2(dd, cuddZddWeakDivF, f, g, zero);
Cudd_Deref(q);
return(zero);
}
if (gd != zero) {
Cudd_RecursiveDerefZdd(dd, q);
tmp = cuddZddWeakDivF(dd, fd, gd);
if (tmp == NULL) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
return(NULL);
}
Cudd_Ref(tmp);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
if (q == g)
q = tmp;
else {
q = cuddZddIntersect(dd, q, tmp);
if (q == NULL) {
Cudd_RecursiveDerefZdd(dd, tmp);
return(NULL);
}
Cudd_Ref(q);
Cudd_RecursiveDerefZdd(dd, tmp);
}
}
else {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDerefZdd(dd, gd);
}
cuddCacheInsert2(dd, cuddZddWeakDivF, f, g, q);
Cudd_Deref(q);
return(q);
} /* end of cuddZddWeakDivF */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddIsop.]
Description []
SideEffects [None]
SeeAlso [Cudd_zddIsop]
******************************************************************************/
DdNode *
cuddZddIsop(
DdManager * dd,
DdNode * L,
DdNode * U,
DdNode ** zdd_I)
{
DdNode *one = DD_ONE(dd);
DdNode *zero = Cudd_Not(one);
DdNode *zdd_one = DD_ONE(dd);
DdNode *zdd_zero = DD_ZERO(dd);
int v, top_l, top_u;
DdNode *Lsub0, *Usub0, *Lsub1, *Usub1, *Ld, *Ud;
DdNode *Lsuper0, *Usuper0, *Lsuper1, *Usuper1;
DdNode *Isub0, *Isub1, *Id;
DdNode *zdd_Isub0, *zdd_Isub1, *zdd_Id;
DdNode *x;
DdNode *term0, *term1, *sum;
DdNode *Lv, *Uv, *Lnv, *Unv;
DdNode *r, *y, *z;
int index;
DdNode *(*cacheOp)(DdManager *, DdNode *, DdNode *);
statLine(dd);
if (L == zero) {
*zdd_I = zdd_zero;
return(zero);
}
if (U == one) {
*zdd_I = zdd_one;
return(one);
}
if (U == zero || L == one) {
printf("*** ERROR : illegal condition for ISOP (U < L).\n");
exit(1);
}
/* Check the cache. We store two results for each recursive call.
** One is the BDD, and the other is the ZDD. Both are needed.
** Hence we need a double hit in the cache to terminate the
** recursion. Clearly, collisions may evict only one of the two
** results. */
cacheOp = (DdNode *(*)(DdManager *, DdNode *, DdNode *)) cuddZddIsop;
r = cuddCacheLookup2(dd, cuddBddIsop, L, U);
if (r) {
*zdd_I = cuddCacheLookup2Zdd(dd, cacheOp, L, U);
if (*zdd_I)
return(r);
else {
/* The BDD result may have been dead. In that case
** cuddCacheLookup2 would have called cuddReclaim,
** whose effects we now have to undo. */
cuddRef(r);
Cudd_RecursiveDeref(dd, r);
}
}
top_l = dd->perm[Cudd_Regular(L)->index];
top_u = dd->perm[Cudd_Regular(U)->index];
v = ddMin(top_l, top_u);
/* Compute cofactors. */
if (top_l == v) {
index = Cudd_Regular(L)->index;
Lv = Cudd_T(L);
Lnv = Cudd_E(L);
if (Cudd_IsComplement(L)) {
Lv = Cudd_Not(Lv);
Lnv = Cudd_Not(Lnv);
}
}
else {
index = Cudd_Regular(U)->index;
Lv = Lnv = L;
}
if (top_u == v) {
Uv = Cudd_T(U);
Unv = Cudd_E(U);
if (Cudd_IsComplement(U)) {
Uv = Cudd_Not(Uv);
Unv = Cudd_Not(Unv);
}
}
else {
Uv = Unv = U;
}
Lsub0 = cuddBddAndRecur(dd, Lnv, Cudd_Not(Uv));
if (Lsub0 == NULL)
return(NULL);
Cudd_Ref(Lsub0);
Usub0 = Unv;
Lsub1 = cuddBddAndRecur(dd, Lv, Cudd_Not(Unv));
if (Lsub1 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
return(NULL);
}
Cudd_Ref(Lsub1);
Usub1 = Uv;
Isub0 = cuddZddIsop(dd, Lsub0, Usub0, &zdd_Isub0);
if (Isub0 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
return(NULL);
}
/*
if ((!cuddIsConstant(Cudd_Regular(Isub0))) &&
(Cudd_Regular(Isub0)->index != zdd_Isub0->index / 2 ||
dd->permZ[index * 2] > dd->permZ[zdd_Isub0->index])) {
printf("*** ERROR : illegal permutation in ZDD. ***\n");
}
*/
Cudd_Ref(Isub0);
Cudd_Ref(zdd_Isub0);
Isub1 = cuddZddIsop(dd, Lsub1, Usub1, &zdd_Isub1);
if (Isub1 == NULL) {
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
return(NULL);
}
/*
if ((!cuddIsConstant(Cudd_Regular(Isub1))) &&
(Cudd_Regular(Isub1)->index != zdd_Isub1->index / 2 ||
dd->permZ[index * 2] > dd->permZ[zdd_Isub1->index])) {
printf("*** ERROR : illegal permutation in ZDD. ***\n");
}
*/
Cudd_Ref(Isub1);
Cudd_Ref(zdd_Isub1);
Cudd_RecursiveDeref(dd, Lsub0);
Cudd_RecursiveDeref(dd, Lsub1);
Lsuper0 = cuddBddAndRecur(dd, Lnv, Cudd_Not(Isub0));
if (Lsuper0 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
return(NULL);
}
Cudd_Ref(Lsuper0);
Lsuper1 = cuddBddAndRecur(dd, Lv, Cudd_Not(Isub1));
if (Lsuper1 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
return(NULL);
}
Cudd_Ref(Lsuper1);
Usuper0 = Unv;
Usuper1 = Uv;
/* Ld = Lsuper0 + Lsuper1 */
Ld = cuddBddAndRecur(dd, Cudd_Not(Lsuper0), Cudd_Not(Lsuper1));
if (Ld == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
return(NULL);
}
Ld = Cudd_Not(Ld);
Cudd_Ref(Ld);
/* Ud = Usuper0 * Usuper1 */
Ud = cuddBddAndRecur(dd, Usuper0, Usuper1);
if (Ud == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
Cudd_RecursiveDeref(dd, Ld);
return(NULL);
}
Cudd_Ref(Ud);
Cudd_RecursiveDeref(dd, Lsuper0);
Cudd_RecursiveDeref(dd, Lsuper1);
Id = cuddZddIsop(dd, Ld, Ud, &zdd_Id);
if (Id == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Ld);
Cudd_RecursiveDeref(dd, Ud);
return(NULL);
}
/*
if ((!cuddIsConstant(Cudd_Regular(Id))) &&
(Cudd_Regular(Id)->index != zdd_Id->index / 2 ||
dd->permZ[index * 2] > dd->permZ[zdd_Id->index])) {
printf("*** ERROR : illegal permutation in ZDD. ***\n");
}
*/
Cudd_Ref(Id);
Cudd_Ref(zdd_Id);
Cudd_RecursiveDeref(dd, Ld);
Cudd_RecursiveDeref(dd, Ud);
x = cuddUniqueInter(dd, index, one, zero);
if (x == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
return(NULL);
}
Cudd_Ref(x);
/* term0 = x * Isub0 */
term0 = cuddBddAndRecur(dd, Cudd_Not(x), Isub0);
if (term0 == NULL) {
Cudd_RecursiveDeref(dd, Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, x);
return(NULL);
}
Cudd_Ref(term0);
Cudd_RecursiveDeref(dd, Isub0);
/* term1 = x * Isub1 */
term1 = cuddBddAndRecur(dd, x, Isub1);
if (term1 == NULL) {
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDeref(dd, Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, x);
Cudd_RecursiveDeref(dd, term0);
return(NULL);
}
Cudd_Ref(term1);
Cudd_RecursiveDeref(dd, x);
Cudd_RecursiveDeref(dd, Isub1);
/* sum = term0 + term1 */
sum = cuddBddAndRecur(dd, Cudd_Not(term0), Cudd_Not(term1));
if (sum == NULL) {
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, term0);
Cudd_RecursiveDeref(dd, term1);
return(NULL);
}
sum = Cudd_Not(sum);
Cudd_Ref(sum);
Cudd_RecursiveDeref(dd, term0);
Cudd_RecursiveDeref(dd, term1);
/* r = sum + Id */
r = cuddBddAndRecur(dd, Cudd_Not(sum), Cudd_Not(Id));
r = Cudd_NotCond(r, r != NULL);
if (r == NULL) {
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDeref(dd, Id);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, sum);
return(NULL);
}
Cudd_Ref(r);
Cudd_RecursiveDeref(dd, sum);
Cudd_RecursiveDeref(dd, Id);
if (zdd_Isub0 != zdd_zero) {
z = cuddZddGetNodeIVO(dd, index * 2 + 1, zdd_Isub0, zdd_Id);
if (z == NULL) {
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, r);
return(NULL);
}
}
else {
z = zdd_Id;
}
Cudd_Ref(z);
if (zdd_Isub1 != zdd_zero) {
y = cuddZddGetNodeIVO(dd, index * 2, zdd_Isub1, z);
if (y == NULL) {
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDeref(dd, r);
Cudd_RecursiveDerefZdd(dd, z);
return(NULL);
}
}
else
y = z;
Cudd_Ref(y);
Cudd_RecursiveDerefZdd(dd, zdd_Isub0);
Cudd_RecursiveDerefZdd(dd, zdd_Isub1);
Cudd_RecursiveDerefZdd(dd, zdd_Id);
Cudd_RecursiveDerefZdd(dd, z);
cuddCacheInsert2(dd, cuddBddIsop, L, U, r);
cuddCacheInsert2(dd, cacheOp, L, U, y);
Cudd_Deref(r);
Cudd_Deref(y);
*zdd_I = y;
/*
if (Cudd_Regular(r)->index != y->index / 2) {
printf("*** ERROR : mismatch in indices between BDD and ZDD. ***\n");
}
*/
return(r);
} /* end of cuddZddIsop */
/**Function********************************************************************
Synopsis [Performs the recursive step of
Cudd_bddLiteralSetIntersection.]
Description [Performs the recursive step of
Cudd_bddLiteralSetIntersection. Scans the cubes for common variables,
and checks whether they agree in phase. Returns a pointer to the
resulting cube if successful; NULL otherwise.]
SideEffects [None]
******************************************************************************/
DdNode *
cuddBddLiteralSetIntersectionRecur(
DdManager * dd,
DdNode * f,
DdNode * g)
{
DdNode *res, *tmp;
DdNode *F, *G;
DdNode *fc, *gc;
DdNode *one;
DdNode *zero;
unsigned int topf, topg, comple;
int phasef, phaseg;
statLine(dd);
if (f == g) return(f);
F = Cudd_Regular(f);
G = Cudd_Regular(g);
one = DD_ONE(dd);
/* Here f != g. If F == G, then f and g are complementary.
** Since they are two cubes, this case only occurs when f == v,
** g == v', and v is a variable or its complement.
*/
if (F == G) return(one);
zero = Cudd_Not(one);
topf = cuddI(dd,F->index);
topg = cuddI(dd,G->index);
/* Look for a variable common to both cubes. If there are none, this
** loop will stop when the constant node is reached in both cubes.
*/
while (topf != topg) {
if (topf < topg) { /* move down on f */
comple = f != F;
f = cuddT(F);
if (comple) f = Cudd_Not(f);
if (f == zero) {
f = cuddE(F);
if (comple) f = Cudd_Not(f);
}
F = Cudd_Regular(f);
topf = cuddI(dd,F->index);
} else if (topg < topf) {
comple = g != G;
g = cuddT(G);
if (comple) g = Cudd_Not(g);
if (g == zero) {
g = cuddE(G);
if (comple) g = Cudd_Not(g);
}
G = Cudd_Regular(g);
topg = cuddI(dd,G->index);
}
}
/* At this point, f == one <=> g == 1. It suffices to test one of them. */
if (f == one) return(one);
res = cuddCacheLookup2(dd,Cudd_bddLiteralSetIntersection,f,g);
if (res != NULL) {
return(res);
}
/* Here f and g are both non constant and have the same top variable. */
comple = f != F;
fc = cuddT(F);
phasef = 1;
if (comple) fc = Cudd_Not(fc);
if (fc == zero) {
fc = cuddE(F);
phasef = 0;
if (comple) fc = Cudd_Not(fc);
}
comple = g != G;
gc = cuddT(G);
phaseg = 1;
if (comple) gc = Cudd_Not(gc);
if (gc == zero) {
gc = cuddE(G);
phaseg = 0;
if (comple) gc = Cudd_Not(gc);
}
tmp = cuddBddLiteralSetIntersectionRecur(dd,fc,gc);
if (tmp == NULL) {
return(NULL);
}
if (phasef != phaseg) {
res = tmp;
} else {
cuddRef(tmp);
if (phasef == 0) {
res = cuddBddAndRecur(dd,Cudd_Not(dd->vars[F->index]),tmp);
} else {
res = cuddBddAndRecur(dd,dd->vars[F->index],tmp);
}
if (res == NULL) {
Cudd_RecursiveDeref(dd,tmp);
return(NULL);
}
cuddDeref(tmp); /* Just cuddDeref, because it is included in result */
}
cuddCacheInsert2(dd,Cudd_bddLiteralSetIntersection,f,g,res);
return(res);
} /* end of cuddBddLiteralSetIntersectionRecur */
/**Function********************************************************************
Synopsis [Converts a ZDD cover to a BDD graph.]
Description [Converts a ZDD cover to a BDD graph. If successful, it
returns a BDD node, otherwise it returns NULL. It is a recursive
algorithm as the following. First computes 3 cofactors of a ZDD cover;
f1, f0 and fd. Second, compute BDDs(b1, b0 and bd) of f1, f0 and fd.
Third, compute T=b1+bd and E=b0+bd. Fourth, compute ITE(v,T,E) where v
is the variable which has the index of the top node of the ZDD cover.
In this case, since the index of v can be larger than either one of T or
one of E, cuddUniqueInterIVO is called, here IVO stands for
independent variable ordering.]
SideEffects []
SeeAlso [Cudd_MakeBddFromZddCover]
******************************************************************************/
DdNode *
cuddMakeBddFromZddCover(
DdManager * dd,
DdNode * node)
{
DdNode *neW;
int v;
DdNode *f1, *f0, *fd;
DdNode *b1, *b0, *bd;
DdNode *T, *E;
statLine(dd);
if (node == dd->one)
return(dd->one);
if (node == dd->zero)
return(Cudd_Not(dd->one));
/* Check cache */
neW = cuddCacheLookup1(dd, cuddMakeBddFromZddCover, node);
if (neW)
return(neW);
v = Cudd_Regular(node)->index; /* either yi or zi */
cuddZddGetCofactors3(dd, node, v, &f1, &f0, &fd);
Cudd_Ref(f1);
Cudd_Ref(f0);
Cudd_Ref(fd);
b1 = cuddMakeBddFromZddCover(dd, f1);
if (!b1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
return(NULL);
}
Cudd_Ref(b1);
b0 = cuddMakeBddFromZddCover(dd, f0);
if (!b1) {
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDeref(dd, b1);
return(NULL);
}
Cudd_Ref(b0);
Cudd_RecursiveDerefZdd(dd, f1);
Cudd_RecursiveDerefZdd(dd, f0);
if (fd != dd->zero) {
bd = cuddMakeBddFromZddCover(dd, fd);
if (!bd) {
Cudd_RecursiveDerefZdd(dd, fd);
Cudd_RecursiveDeref(dd, b1);
Cudd_RecursiveDeref(dd, b0);
return(NULL);
}
Cudd_Ref(bd);
Cudd_RecursiveDerefZdd(dd, fd);
T = cuddBddAndRecur(dd, Cudd_Not(b1), Cudd_Not(bd));
if (!T) {
Cudd_RecursiveDeref(dd, b1);
Cudd_RecursiveDeref(dd, b0);
Cudd_RecursiveDeref(dd, bd);
return(NULL);
}
T = Cudd_NotCond(T, T != NULL);
Cudd_Ref(T);
Cudd_RecursiveDeref(dd, b1);
E = cuddBddAndRecur(dd, Cudd_Not(b0), Cudd_Not(bd));
if (!E) {
Cudd_RecursiveDeref(dd, b0);
Cudd_RecursiveDeref(dd, bd);
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
E = Cudd_NotCond(E, E != NULL);
Cudd_Ref(E);
Cudd_RecursiveDeref(dd, b0);
Cudd_RecursiveDeref(dd, bd);
}
else {
Cudd_RecursiveDerefZdd(dd, fd);
T = b1;
E = b0;
}
if (Cudd_IsComplement(T)) {
neW = cuddUniqueInterIVO(dd, v / 2, Cudd_Not(T), Cudd_Not(E));
if (!neW) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
neW = Cudd_Not(neW);
}
else {
neW = cuddUniqueInterIVO(dd, v / 2, T, E);
if (!neW) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
Cudd_Ref(neW);
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
cuddCacheInsert1(dd, cuddMakeBddFromZddCover, node, neW);
Cudd_Deref(neW);
return(neW);
} /* end of cuddMakeBddFromZddCover */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_zddPortFromBdd.]
Description []
SideEffects [None]
SeeAlso []
******************************************************************************/
static DdNode *
zddPortFromBddStep(
DdManager * dd,
DdNode * B,
int expected)
{
DdNode *res, *prevZdd, *t, *e;
DdNode *Breg, *Bt, *Be;
int id, level;
statLine(dd);
/* Terminal cases. */
if (B == Cudd_Not(DD_ONE(dd)))
return(DD_ZERO(dd));
if (B == DD_ONE(dd)) {
if (expected >= dd->sizeZ) {
return(DD_ONE(dd));
} else {
return(dd->univ[expected]);
}
}
Breg = Cudd_Regular(B);
/* Computed table look-up. */
res = cuddCacheLookup1Zdd(dd,Cudd_zddPortFromBdd,B);
if (res != NULL) {
level = cuddI(dd,Breg->index);
/* Adding DC vars. */
if (expected < level) {
/* Add suppressed variables. */
cuddRef(res);
for (level--; level >= expected; level--) {
prevZdd = res;
id = dd->invperm[level];
res = cuddZddGetNode(dd, id, prevZdd, prevZdd);
if (res == NULL) {
Cudd_RecursiveDerefZdd(dd, prevZdd);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDerefZdd(dd, prevZdd);
}
cuddDeref(res);
}
return(res);
} /* end of cache look-up */
if (Cudd_IsComplement(B)) {
Bt = Cudd_Not(cuddT(Breg));
Be = Cudd_Not(cuddE(Breg));
} else {
Bt = cuddT(Breg);
Be = cuddE(Breg);
}
id = Breg->index;
level = cuddI(dd,id);
t = zddPortFromBddStep(dd, Bt, level+1);
if (t == NULL) return(NULL);
cuddRef(t);
e = zddPortFromBddStep(dd, Be, level+1);
if (e == NULL) {
Cudd_RecursiveDerefZdd(dd, t);
return(NULL);
}
cuddRef(e);
res = cuddZddGetNode(dd, id, t, e);
if (res == NULL) {
Cudd_RecursiveDerefZdd(dd, t);
Cudd_RecursiveDerefZdd(dd, e);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDerefZdd(dd, t);
Cudd_RecursiveDerefZdd(dd, e);
cuddCacheInsert1(dd,Cudd_zddPortFromBdd,B,res);
for (level--; level >= expected; level--) {
prevZdd = res;
id = dd->invperm[level];
res = cuddZddGetNode(dd, id, prevZdd, prevZdd);
if (res == NULL) {
Cudd_RecursiveDerefZdd(dd, prevZdd);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDerefZdd(dd, prevZdd);
}
cuddDeref(res);
return(res);
} /* end of zddPortFromBddStep */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addOrAbstract.]
Description [Performs the recursive step of Cudd_addOrAbstract.
Returns the ADD obtained by abstracting the variables of cube from f,
if successful; NULL otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddAddOrAbstractRecur(
DdManager * manager,
DdNode * f,
DdNode * cube)
{
DdNode *T, *E, *res, *res1, *res2, *one;
statLine(manager);
one = DD_ONE(manager);
/* Cube is guaranteed to be a cube at this point. */
if (cuddIsConstant(f) || cube == one) {
return(f);
}
/* Abstract a variable that does not appear in f. */
if (cuddI(manager,f->index) > cuddI(manager,cube->index)) {
res = cuddAddOrAbstractRecur(manager, f, cuddT(cube));
return(res);
}
if ((res = cuddCacheLookup2(manager, Cudd_addOrAbstract, f, cube)) != NULL) {
return(res);
}
T = cuddT(f);
E = cuddE(f);
/* If the two indices are the same, so are their levels. */
if (f->index == cube->index) {
res1 = cuddAddOrAbstractRecur(manager, T, cuddT(cube));
if (res1 == NULL) return(NULL);
cuddRef(res1);
if (res1 != one) {
res2 = cuddAddOrAbstractRecur(manager, E, cuddT(cube));
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = cuddAddApplyRecur(manager, Cudd_addOr, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
} else {
res = res1;
}
cuddCacheInsert2(manager, Cudd_addOrAbstract, f, cube, res);
cuddDeref(res);
return(res);
} else { /* if (cuddI(manager,f->index) < cuddI(manager,cube->index)) */
res1 = cuddAddOrAbstractRecur(manager, T, cube);
if (res1 == NULL) return(NULL);
cuddRef(res1);
res2 = cuddAddOrAbstractRecur(manager, E, cube);
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = (res1 == res2) ? res1 :
cuddUniqueInter(manager, (int) f->index, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddDeref(res1);
cuddDeref(res2);
cuddCacheInsert2(manager, Cudd_addOrAbstract, f, cube, res);
return(res);
}
} /* end of cuddAddOrAbstractRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Extra_TransferPermute.]
Description [Performs the recursive step of Extra_TransferPermute.
Returns a pointer to the result if successful; NULL otherwise.]
SideEffects [None]
SeeAlso [extraTransferPermuteTime]
******************************************************************************/
static DdNode *
extraTransferPermuteRecurTime(
DdManager * ddS,
DdManager * ddD,
DdNode * f,
st_table * table,
int * Permute,
int TimeOut )
{
DdNode *ft, *fe, *t, *e, *var, *res;
DdNode *one, *zero;
int index;
int comple = 0;
statLine( ddD );
one = DD_ONE( ddD );
comple = Cudd_IsComplement( f );
/* Trivial cases. */
if ( Cudd_IsConstant( f ) )
return ( Cudd_NotCond( one, comple ) );
/* Make canonical to increase the utilization of the cache. */
f = Cudd_NotCond( f, comple );
/* Now f is a regular pointer to a non-constant node. */
/* Check the cache. */
if ( st_lookup( table, ( char * ) f, ( char ** ) &res ) )
return ( Cudd_NotCond( res, comple ) );
if ( TimeOut && TimeOut < clock() )
return NULL;
/* Recursive step. */
if ( Permute )
index = Permute[f->index];
else
index = f->index;
ft = cuddT( f );
fe = cuddE( f );
t = extraTransferPermuteRecurTime( ddS, ddD, ft, table, Permute, TimeOut );
if ( t == NULL )
{
return ( NULL );
}
cuddRef( t );
e = extraTransferPermuteRecurTime( ddS, ddD, fe, table, Permute, TimeOut );
if ( e == NULL )
{
Cudd_RecursiveDeref( ddD, t );
return ( NULL );
}
cuddRef( e );
zero = Cudd_Not(ddD->one);
var = cuddUniqueInter( ddD, index, one, zero );
if ( var == NULL )
{
Cudd_RecursiveDeref( ddD, t );
Cudd_RecursiveDeref( ddD, e );
return ( NULL );
}
res = cuddBddIteRecur( ddD, var, t, e );
if ( res == NULL )
{
Cudd_RecursiveDeref( ddD, t );
Cudd_RecursiveDeref( ddD, e );
return ( NULL );
}
cuddRef( res );
Cudd_RecursiveDeref( ddD, t );
Cudd_RecursiveDeref( ddD, e );
if ( st_add_direct( table, ( char * ) f, ( char * ) res ) ==
ST_OUT_OF_MEM )
{
Cudd_RecursiveDeref( ddD, res );
return ( NULL );
}
return ( Cudd_NotCond( res, comple ) );
} /* end of extraTransferPermuteRecurTime */
