Example #1
0
/**Function********************************************************************

  Synopsis    [Performs the recursive step of Cuddaux_Support.]

  Description [Performs the recursive step of Cuddaux_Support.]

  SideEffects [None]

  SeeAlso     []

******************************************************************************/
DdNode*
cuddauxSupportRecur(DdManager* dd,
		    DdNode * f)
{
  DdNode *one, *fv, *fvn, *T,*E, *res, *res1;

  one = DD_ONE(dd);
  if (cuddIsConstant(f)) {
    return one;
  }
  fv = cuddT(f);
  fvn = Cudd_Regular(cuddE(f));
  if (cuddIsConstant(fv) && cuddIsConstant(fvn)){
    return dd->vars[f->index];
  }
  /* Look in the cache */
  res = cuddCacheLookup1(dd,Cuddaux_Support,f);
  if (res != NULL)
    return(res);

  T = cuddIsConstant(fv) ? one : cuddauxSupportRecur(dd,fv);
  if (T == NULL)
    return(NULL);
  cuddRef(T);
  E = cuddIsConstant(fvn) ? one : cuddauxSupportRecur(dd,fvn);
  if (E == NULL){
    Cudd_IterDerefBdd(dd,T);
    return(NULL);
  }
  if (T==E){
    res = cuddUniqueInter(dd,f->index,T,Cudd_Not(one));
    if (res == NULL){
      Cudd_IterDerefBdd(dd,T);
      return NULL;
    }
    cuddDeref(T);
  }
  else {
    cuddRef(E);
    res1 = cuddBddAndRecur(dd,T,E);
    if (res1 == NULL){
      Cudd_IterDerefBdd(dd,T);
      Cudd_IterDerefBdd(dd,E);
      return(NULL);
    }
    cuddRef(res1);
    Cudd_IterDerefBdd(dd,T);
    Cudd_IterDerefBdd(dd,E);
    res = cuddUniqueInter(dd,f->index,res1,Cudd_Not(one));
    if (res == NULL){
      Cudd_IterDerefBdd(dd,T);
      Cudd_IterDerefBdd(dd,E);
      Cudd_IterDerefBdd(dd,res1);
      return(NULL);
    }
    cuddDeref(res1);
  }
  cuddCacheInsert1(dd,Cuddaux_Support,f,res);
  return(res);
} /* end of cuddauxSupportRecur */
Example #2
0
/**Function********************************************************************

  Synopsis    [Recursive procedure to extract n mintems from constant 1.]

  Description [Recursive procedure to extract n mintems from constant 1.]

  SideEffects [None]

******************************************************************************/
static DdNode *
mintermsFromUniverse(
  DdManager * manager,
  DdNode ** vars,
  int  numVars,
  double  n,
  int  index)
{
    DdNode *one, *zero;
    DdNode *q, *result;
    double max, max2;
    
    statLine(manager);
    one = DD_ONE(manager);
    zero = Cudd_Not(one);

    max = pow(2.0, (double)numVars);
    max2 = max / 2.0;

    if (n == max)
	return(one);
    if (n == 0.0)
	return(zero);
    /* if n == 2^(numVars-1), return a single variable */
    if (n == max2)
	return vars[index];
    else if (n > max2) {
	/* When n > 2^(numVars-1), a single variable vars[index]
	** contains 2^(numVars-1) minterms. The rest are extracted
	** from a constant with 1 less variable.
	*/
	q = mintermsFromUniverse(manager,vars,numVars-1,(n-max2),index+1);
	if (q == NULL)
	    return(NULL);
	cuddRef(q);
	result = cuddBddIteRecur(manager,vars[index],one,q);
    } else {
	/* When n < 2^(numVars-1), a literal of variable vars[index]
	** is selected. The required n minterms are extracted from a
	** constant with 1 less variable.
	*/
	q = mintermsFromUniverse(manager,vars,numVars-1,n,index+1);
	if (q == NULL)
	    return(NULL);
	cuddRef(q);
	result = cuddBddAndRecur(manager,vars[index],q);
    }
    
    if (result == NULL) {
	Cudd_RecursiveDeref(manager,q);
	return(NULL);
    }
    cuddRef(result);
    Cudd_RecursiveDeref(manager,q);
    cuddDeref(result);
    return(result);

} /* end of mintermsFromUniverse */
Example #3
0
/**Function********************************************************************

  Synopsis    [Computes the NOR of two BDDs f and g.]

  Description [Computes the NOR of two BDDs f and g. Returns a
  pointer to the resulting BDD if successful; NULL if the intermediate
  result blows up.]

  SideEffects [None]

  SeeAlso     [Cudd_bddIte Cudd_addApply Cudd_bddAnd Cudd_bddOr Cudd_bddNand
  Cudd_bddXor Cudd_bddXnor]

******************************************************************************/
DdNode *
Cudd_bddNor(
  DdManager * dd,
  DdNode * f,
  DdNode * g)
{
    DdNode *res;

    do {
        dd->reordered = 0;
        res = cuddBddAndRecur(dd,Cudd_Not(f),Cudd_Not(g));
    } while (dd->reordered == 1);
    return(res);

} /* end of Cudd_bddNor */
Example #4
0
/**Function********************************************************************

  Synopsis    [Computes the conjunction of two BDDs f and g.]

  Description [Computes the conjunction of two BDDs f and g. Returns a
  pointer to the resulting BDD if successful; NULL if the intermediate
  result blows up.]

  SideEffects [None]

  SeeAlso     [Cudd_bddIte Cudd_addApply Cudd_bddAndAbstract Cudd_bddIntersect
  Cudd_bddOr Cudd_bddNand Cudd_bddNor Cudd_bddXor Cudd_bddXnor]

******************************************************************************/
DdNode *
Cudd_bddAnd(
  DdManager * dd,
  DdNode * f,
  DdNode * g)
{
    DdNode *res;

    do {
        dd->reordered = 0;
        res = cuddBddAndRecur(dd,f,g);
    } while (dd->reordered == 1);
    return(res);

} /* end of Cudd_bddAnd */
/**Function********************************************************************

  Synopsis    [Computes the NAND of two BDDs f and g.]

  Description [Computes the NAND of two BDDs f and g. Returns a
  pointer to the resulting BDD if successful; (uintptr_t) 0 if the intermediate
  result blows up.]

  SideEffects [None]

  SeeAlso     [Cudd_bddIte Cudd_addApply Cudd_bddAnd Cudd_bddOr Cudd_bddNor
  Cudd_bddXor Cudd_bddXnor]

******************************************************************************/
DdNode *
Cudd_bddNand(
  DdManager * dd,
  DdNode * f,
  DdNode * g)
{
    DdNode *res;

    do {
	dd->reordered = 0;
	res = cuddBddAndRecur(dd,f,g);
    } while (dd->reordered == 1);
    res = Cudd_NotCond(res,res != (uintptr_t) 0);
    return(res);

} /* end of Cudd_bddNand */
Example #6
0
/**Function********************************************************************

  Synopsis    [Computes the conjunction of two BDDs f and g.  Returns
  NULL if too many nodes are required.]

  Description [Computes the conjunction of two BDDs f and g. Returns a
  pointer to the resulting BDD if successful; NULL if the intermediate
  result blows up or more new nodes than <code>limit</code> are
  required.]

  SideEffects [None]

  SeeAlso     [Cudd_bddAnd]

******************************************************************************/
DdNode *
Cudd_bddAndLimit(
  DdManager * dd,
  DdNode * f,
  DdNode * g,
  unsigned int limit)
{
    DdNode *res;
    unsigned int saveLimit = dd->maxLive;

    dd->maxLive = (dd->keys - dd->dead) + (dd->keysZ - dd->deadZ) + limit;
    do {
        dd->reordered = 0;
        res = cuddBddAndRecur(dd,f,g);
    } while (dd->reordered == 1);
    dd->maxLive = saveLimit;
    return(res);

} /* end of Cudd_bddAndLimit */
Example #7
0
/**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 */
Example #8
0
/**Function*************************************************************

  Synopsis    [Performs the recursive step of Extra_bddSpaceFromFunctionPos().]

  Description []

  SideEffects []

  SeeAlso     []

***********************************************************************/
DdNode * extraBddSpaceFromMatrixNeg( DdManager * dd, DdNode * zA )
{
	DdNode * bRes;
	statLine( dd );

	if ( zA == z0 )
		return b1;
	if ( zA == z1 )
		return b0;

    if ( (bRes = cuddCacheLookup1(dd, extraBddSpaceFromMatrixNeg, zA)) )
    	return bRes;
	else
	{
		DdNode * bP0, * bP1;
		DdNode * bN0, * bN1;
		DdNode * bRes0, * bRes1; 

		bP0  = extraBddSpaceFromMatrixNeg( dd, cuddE(zA) );
		if ( bP0 == NULL )
			return NULL;
		cuddRef( bP0 );

		bP1  = extraBddSpaceFromMatrixNeg( dd, cuddT(zA) );
		if ( bP1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bP0 );
			return NULL;
		}
		cuddRef( bP1 );

		bRes0  = cuddBddAndRecur( dd, bP0, bP1 );
		if ( bRes0 == NULL )
		{
			Cudd_RecursiveDeref( dd, bP0 );
			Cudd_RecursiveDeref( dd, bP1 );
			return NULL;
		}
		cuddRef( bRes0 );
		Cudd_RecursiveDeref( dd, bP0 );
		Cudd_RecursiveDeref( dd, bP1 );


		bN0  = extraBddSpaceFromMatrixNeg( dd, cuddE(zA) );
		if ( bN0 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			return NULL;
		}
		cuddRef( bN0 );

		bN1  = extraBddSpaceFromMatrixPos( dd, cuddT(zA) );
		if ( bN1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bN0 );
			return NULL;
		}
		cuddRef( bN1 );

		bRes1  = cuddBddAndRecur( dd, bN0, bN1 );
		if ( bRes1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bN0 );
			Cudd_RecursiveDeref( dd, bN1 );
			return NULL;
		}
		cuddRef( bRes1 );
		Cudd_RecursiveDeref( dd, bN0 );
		Cudd_RecursiveDeref( dd, bN1 );


		// consider the case when Res0 and Res1 are the same node 
		if ( bRes0 == bRes1 )
			bRes = bRes1;
		// consider the case when Res1 is complemented 
		else if ( Cudd_IsComplement(bRes1) ) 
		{
			bRes = cuddUniqueInter( dd, zA->index/2, Cudd_Not(bRes1), Cudd_Not(bRes0) );
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
			bRes = Cudd_Not(bRes);
		} 
		else 
		{
			bRes = cuddUniqueInter( dd, zA->index/2, bRes1, bRes0 );
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
		}
		cuddDeref( bRes0 );
		cuddDeref( bRes1 );

		cuddCacheInsert1( dd, extraBddSpaceFromMatrixNeg, zA, bRes );
		return bRes;
	}
}
Example #9
0
/**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)) {
	if (!st_lookup(mtable, Nv, &dummy)) return(NULL);
	numT = *dummy/(2*(1<<index));
    } else if (Nv == one) {
	numT = max/(2*(1<<index));
    } else {
	numT = 0;
    }
  
    if (!Cudd_IsConstant(Nnv)) {
	if (!st_lookup(mtable, Nnv, &dummy)) return(NULL);
	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 */
Example #10
0
/**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 ( manager->TimeStop && manager->TimeStop < clock() )
        return NULL;

    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 */
Example #11
0
/**Function********************************************************************

  Synopsis [Takes the exclusive OR of two BDDs and simultaneously abstracts the
  variables in cube.]

  Description [Takes the exclusive OR 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 *
cuddBddXorExistAbstractRecur(
  DdManager * manager,
  DdNode * f,
  DdNode * g,
  DdNode * cube)
{
    DdNode *F, *fv, *fnv, *G, *gv, *gnv;
    DdNode *one, *zero, *r, *t, *e, *Cube;
    unsigned int topf, topg, topcube, top, index;

    statLine(manager);
    one = DD_ONE(manager);
    zero = Cudd_Not(one);

    /* Terminal cases. */
    if (f == g) {
	return(zero);
    }
    if (f == Cudd_Not(g)) {
	return(one);
    }
    if (cube == one) {
	return(cuddBddXorRecur(manager, f, g));
    }
    if (f == one) {
	return(cuddBddExistAbstractRecur(manager, Cudd_Not(g), cube));
    }
    if (g == one) {
	return(cuddBddExistAbstractRecur(manager, Cudd_Not(f), cube));
    }
    if (f == zero) {
	return(cuddBddExistAbstractRecur(manager, g, cube));
    }
    if (g == zero) {
	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;
    }

    /* Check cache. */
    r = cuddCacheLookup(manager, DD_BDD_XOR_EXIST_ABSTRACT_TAG, 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.
    */
    F = Cudd_Regular(f);
    topf = manager->perm[F->index];
    G = Cudd_Regular(g);
    topg = manager->perm[G->index];
    top = ddMin(topf, topg);
    topcube = manager->perm[cube->index];

    if (topcube < top) {
	return(cuddBddXorExistAbstractRecur(manager, f, g, cuddT(cube)));
    }
    /* Now, topcube >= top. */

    if (topf == top) {
	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 == top) {
	gv = cuddT(G);
	gnv = cuddE(G);
	if (Cudd_IsComplement(g)) {
	    gv = Cudd_Not(gv);
	    gnv = Cudd_Not(gnv);
	}
    } else {
	gv = gnv = g;
    }

    if (topcube == top) {
	Cube = cuddT(cube);
    } else {
	Cube = cube;
    }

    t = cuddBddXorExistAbstractRecur(manager, fv, gv, Cube);
    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) {
	cuddCacheInsert(manager, DD_BDD_XOR_EXIST_ABSTRACT_TAG, f, g, cube, one);
	return(one);
    }
    cuddRef(t);

    e = cuddBddXorExistAbstractRecur(manager, fnv, gnv, Cube);
    if (e == NULL) {
	Cudd_IterDerefBdd(manager, t);
	return(NULL);
    }
    cuddRef(e);

    if (topcube == top) {	/* abstract */
	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_IterDerefBdd(manager, t);
	Cudd_IterDerefBdd(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_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);
    }
    cuddCacheInsert(manager, DD_BDD_XOR_EXIST_ABSTRACT_TAG, f, g, cube, r);
    return (r);

} /* end of cuddBddXorExistAbstractRecur */
Example #12
0
/**Function********************************************************************

  Synopsis    [Performs the recursive steps of Cudd_bddExistAbstract.]

  Description [Performs the recursive steps of Cudd_bddExistAbstract.
  Returns the BDD obtained by abstracting the variables
  of cube from f if successful; NULL otherwise. It is also used by
  Cudd_bddUnivAbstract.]

  SideEffects [None]

  SeeAlso     [Cudd_bddExistAbstract Cudd_bddUnivAbstract]

******************************************************************************/
DdNode *
cuddBddExistAbstractRecur(
  DdManager * manager,
  DdNode * f,
  DdNode * cube)
{
    DdNode	*F, *T, *E, *res, *res1, *res2, *one;

    statLine(manager);
    one = DD_ONE(manager);
    F = Cudd_Regular(f);

    /* Cube is guaranteed to be a cube at this point. */	
    if (cube == one || F == one) {  
        return(f);
    }
    /* From now on, f and cube are non-constant. */

    /* Abstract a variable that does not appear in f. */
    while (manager->perm[F->index] > manager->perm[cube->index]) {
	cube = cuddT(cube);
	if (cube == one) return(f);
    }

    /* Check the cache. */
    if (F->ref != 1 && (res = cuddCacheLookup2(manager, Cudd_bddExistAbstract, f, cube)) != NULL) {
	return(res);
    }

    /* Compute the cofactors of f. */
    T = cuddT(F); E = cuddE(F);
    if (f != F) {
	T = Cudd_Not(T); E = Cudd_Not(E);
    }

    /* If the two indices are the same, so are their levels. */
    if (F->index == cube->index) {
	if (T == one || E == one || T == Cudd_Not(E)) {
	    return(one);
	}
	res1 = cuddBddExistAbstractRecur(manager, T, cuddT(cube));
	if (res1 == NULL) return(NULL);
	if (res1 == one) {
	    if (F->ref != 1)
		cuddCacheInsert2(manager, Cudd_bddExistAbstract, f, cube, one);
	    return(one);
	}
        cuddRef(res1);
	res2 = cuddBddExistAbstractRecur(manager, E, cuddT(cube));
	if (res2 == NULL) {
	    Cudd_IterDerefBdd(manager,res1);
	    return(NULL);
	}
        cuddRef(res2);
	res = cuddBddAndRecur(manager, Cudd_Not(res1), Cudd_Not(res2));
	if (res == NULL) {
	    Cudd_IterDerefBdd(manager, res1);
	    Cudd_IterDerefBdd(manager, res2);
	    return(NULL);
	}
	res = Cudd_Not(res);
	cuddRef(res);
	Cudd_IterDerefBdd(manager, res1);
	Cudd_IterDerefBdd(manager, res2);
	if (F->ref != 1)
	    cuddCacheInsert2(manager, Cudd_bddExistAbstract, f, cube, res);
	cuddDeref(res);
        return(res);
    } else { /* if (cuddI(manager,F->index) < cuddI(manager,cube->index)) */
	res1 = cuddBddExistAbstractRecur(manager, T, cube);
	if (res1 == NULL) return(NULL);
        cuddRef(res1);
	res2 = cuddBddExistAbstractRecur(manager, E, cube);
	if (res2 == NULL) {
	    Cudd_IterDerefBdd(manager, res1);
	    return(NULL);
	}
        cuddRef(res2);
	/* ITE takes care of possible complementation of res1 and of the
        ** case in which res1 == res2. */
	res = cuddBddIteRecur(manager, manager->vars[F->index], res1, res2);
	if (res == NULL) {
	    Cudd_IterDerefBdd(manager, res1);
	    Cudd_IterDerefBdd(manager, res2);
	    return(NULL);
	}
	cuddDeref(res1);
	cuddDeref(res2);
	if (F->ref != 1)
	    cuddCacheInsert2(manager, Cudd_bddExistAbstract, f, cube, res);
        return(res);
    }	    

} /* end of cuddBddExistAbstractRecur */
Example #13
0
/**Function********************************************************************

  Synopsis    [Performs the recursive step of Cudd_CProjection.]

  Description [Performs the recursive step of Cudd_CProjection. Returns
  the projection if successful; NULL otherwise.]

  SideEffects [None]

  SeeAlso     [Cudd_CProjection]

******************************************************************************/
DdNode *
cuddCProjectionRecur(
  DdManager * dd,
  DdNode * R,
  DdNode * Y,
  DdNode * Ysupp)
{
    DdNode *res, *res1, *res2, *resA;
    DdNode *r, *y, *RT, *RE, *YT, *YE, *Yrest, *Ra, *Ran, *Gamma, *Alpha;
    unsigned int topR, topY, top, index;
    DdNode *one = DD_ONE(dd);

    statLine(dd);
    if (Y == one) return(R);

#ifdef DD_DEBUG
    assert(!Cudd_IsConstant(Y));
#endif

    if (R == Cudd_Not(one)) return(R);

    res = cuddCacheLookup2(dd, Cudd_CProjection, R, Y);
    if (res != NULL) return(res);

    r = Cudd_Regular(R);
    topR = cuddI(dd,r->index);
    y = Cudd_Regular(Y);
    topY = cuddI(dd,y->index);

    top = ddMin(topR, topY);

    /* Compute the cofactors of R */
    if (topR == top) {
	index = r->index;
	RT = cuddT(r);
	RE = cuddE(r);
	if (r != R) {
	    RT = Cudd_Not(RT); RE = Cudd_Not(RE);
	}
    } else {
	RT = RE = R;
    }

    if (topY > top) {
	/* Y does not depend on the current top variable.
	** We just need to compute the results on the two cofactors of R
	** and make them the children of a node labeled r->index.
	*/
	res1 = cuddCProjectionRecur(dd,RT,Y,Ysupp);
	if (res1 == NULL) return(NULL);
	cuddRef(res1);
	res2 = cuddCProjectionRecur(dd,RE,Y,Ysupp);
	if (res2 == NULL) {
	    Cudd_RecursiveDeref(dd,res1);
	    return(NULL);
	}
	cuddRef(res2);
	res = cuddBddIteRecur(dd, dd->vars[index], res1, res2);
	if (res == NULL) {
	    Cudd_RecursiveDeref(dd,res1);
	    Cudd_RecursiveDeref(dd,res2);
	    return(NULL);
	}
	/* If we have reached this point, res1 and res2 are now
	** incorporated in res. cuddDeref is therefore sufficient.
	*/
	cuddDeref(res1);
	cuddDeref(res2);
    } else {
	/* Compute the cofactors of Y */
	index = y->index;
	YT = cuddT(y);
	YE = cuddE(y);
	if (y != Y) {
	    YT = Cudd_Not(YT); YE = Cudd_Not(YE);
	}
	if (YT == Cudd_Not(one)) {
	    Alpha  = Cudd_Not(dd->vars[index]);
	    Yrest = YE;
	    Ra = RE;
	    Ran = RT;
	} else {
	    Alpha = dd->vars[index];
	    Yrest = YT;
	    Ra = RT;
	    Ran = RE;
	}
	Gamma = cuddBddExistAbstractRecur(dd,Ra,cuddT(Ysupp));
	if (Gamma == NULL) return(NULL);
	if (Gamma == one) {
	    res1 = cuddCProjectionRecur(dd,Ra,Yrest,cuddT(Ysupp));
	    if (res1 == NULL) return(NULL);
	    cuddRef(res1);
	    res = cuddBddAndRecur(dd, Alpha, res1);
	    if (res == NULL) {
		Cudd_RecursiveDeref(dd,res1);
		return(NULL);
	    }
	    cuddDeref(res1);
	} else if (Gamma == Cudd_Not(one)) {
	    res1 = cuddCProjectionRecur(dd,Ran,Yrest,cuddT(Ysupp));
	    if (res1 == NULL) return(NULL);
	    cuddRef(res1);
	    res = cuddBddAndRecur(dd, Cudd_Not(Alpha), res1);
	    if (res == NULL) {
		Cudd_RecursiveDeref(dd,res1);
		return(NULL);
	    }
	    cuddDeref(res1);
	} else {
	    cuddRef(Gamma);
	    resA = cuddCProjectionRecur(dd,Ran,Yrest,cuddT(Ysupp));
	    if (resA == NULL) {
		Cudd_RecursiveDeref(dd,Gamma);
		return(NULL);
	    }
	    cuddRef(resA);
	    res2 = cuddBddAndRecur(dd, Cudd_Not(Gamma), resA);
	    if (res2 == NULL) {
		Cudd_RecursiveDeref(dd,Gamma);
		Cudd_RecursiveDeref(dd,resA);
		return(NULL);
	    }
	    cuddRef(res2);
	    Cudd_RecursiveDeref(dd,Gamma);
	    Cudd_RecursiveDeref(dd,resA);
	    res1 = cuddCProjectionRecur(dd,Ra,Yrest,cuddT(Ysupp));
	    if (res1 == NULL) {
		Cudd_RecursiveDeref(dd,res2);
		return(NULL);
	    }
	    cuddRef(res1);
	    res = cuddBddIteRecur(dd, Alpha, res1, res2);
	    if (res == NULL) {
		Cudd_RecursiveDeref(dd,res1);
		Cudd_RecursiveDeref(dd,res2);
		return(NULL);
	    }
	    cuddDeref(res1);
	    cuddDeref(res2);
	}
    }

    cuddCacheInsert2(dd,Cudd_CProjection,R,Y,res);

    return(res);

} /* end of cuddCProjectionRecur */
Example #14
0
/**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 */
Example #15
0
/**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 */
Example #16
0
/**Function********************************************************************

  Synopsis    [Performs the recursive step of Cuddaux_addRestrict.]

  Description [Performs the recursive step of Cuddaux_addRestrict.
  Returns the restricted ADD if successful; otherwise NULL.]

  SideEffects [None]

  SeeAlso     [Cudd_addRestrict]

******************************************************************************/
DdNode *
cuddauxAddRestrictRecur(
  DdManager * dd,
  DdNode * f,
  DdNode * c)
{
  DdNode	 *Fv, *Fnv, *Cv, *Cnv, *t, *e, *res, *one, *zero;
  unsigned int topf, topc;
  int		 index;

  one = DD_ONE(dd);
  zero = Cudd_Not(one);

  /* Trivial cases */
  if (c == one)		return(f);
  if (c == zero){
    fprintf(stderr,"CuddauxAddRestrictRecur: warning: false careset\n");
    return(DD_BACKGROUND(dd));
  }
  if (Cudd_IsConstant(f)) return(f);

  /* Now f and c are non-constant. */

  /* Check the cache. */
  res = cuddCacheLookup2(dd, Cuddaux_addRestrict, f, c);
  if (res != NULL) {
    return(res);
  }

  topf = dd->perm[f->index];
  topc = dd->perm[Cudd_Regular(c)->index];

  if (topc < topf) {	/* abstract top variable from c */
    DdNode *d, *s1, *s2;

    /* Take the OR by applying DeMorgan. */
    /* Find complements of cofactors of c. */
    if (Cudd_IsComplement(c)) {
      s1 = cuddT(Cudd_Regular(c));
      s2 = cuddE(Cudd_Regular(c));
    } else {
      s1 = Cudd_Not(cuddT(c));
      s2 = Cudd_Not(cuddE(c));
    }
    /* Take the AND and negate */
    d = cuddBddAndRecur(dd, s1, s2);
    if (d == NULL) return(NULL);
    d = Cudd_Not(d);
    cuddRef(d);

    res = cuddauxAddRestrictRecur(dd, f, d);
    if (res == NULL) {
      Cudd_IterDerefBdd(dd, d);
      return(NULL);
    }
    cuddRef(res);
    Cudd_IterDerefBdd(dd, d);
    cuddDeref(res);
    cuddCacheInsert2(dd, Cuddaux_addRestrict, f, c, res);
    return(res);
  }

  /* Recursive step. Here topf <= topc. */
  index = f->index;
  Fv = cuddT(f); Fnv = cuddE(f);
  if (topc == topf) {
    Cv = Cudd_T(c); Cnv = Cudd_E(c);
    if (Cudd_IsComplement(c)) {
      Cv = Cudd_Not(Cv); Cnv = Cudd_Not(Cnv);
    }
  } else {
    Cv = Cnv = c;
  }

  if (!Cudd_IsConstant(Cv)) {
    t = cuddauxAddRestrictRecur(dd, Fv, Cv);
    if (t == NULL) return(NULL);
  } 
  else if (Cv == one) {
    t = Fv;
  } 
  else {		/* Cv == zero: return(Fnv @ Cnv) */
    if (Cnv == one) {
      res = Fnv;
    } 
    else {
      res = cuddauxAddRestrictRecur(dd, Fnv, Cnv);
      if (res == NULL) return(NULL);
    }
    return(res);
  }
  cuddRef(t);

  if (!Cudd_IsConstant(Cnv)) {
    e = cuddauxAddRestrictRecur(dd, Fnv, Cnv);
    if (e == NULL) {
      Cudd_RecursiveDeref(dd, t);
      return(NULL);
    }
  } else if (Cnv == one) {
    e = Fnv;
  } else {		/* Cnv == zero: return (Fv @ Cv) previously computed */
    cuddDeref(t);
    return(t);
  }
  cuddRef(e);

  res = (t == e) ? t : cuddUniqueInter(dd, index, t, e);
  if (res == NULL) {
    Cudd_RecursiveDeref(dd, e);
    Cudd_RecursiveDeref(dd, t);
    return(NULL);
  }
  cuddDeref(t);
  cuddDeref(e);

  cuddCacheInsert2(dd, Cuddaux_addRestrict, f, c, res);
  return(res);

} /* end of cuddauxAddRestrictRecur */
Example #17
0
/**Function*************************************************************

  Synopsis    [Performs the recursive step of Extra_bddSpaceFromFunctionPos().]

  Description []

  SideEffects []

  SeeAlso     []

***********************************************************************/
DdNode * extraBddSpaceFromFunctionNeg( DdManager * dd, DdNode * bF )
{
	DdNode * bRes, * bFR;
	statLine( dd );

	bFR = Cudd_Regular(bF);
	if ( cuddIsConstant(bFR) )
		return b0;

    if ( (bRes = cuddCacheLookup1(dd, extraBddSpaceFromFunctionNeg, bF)) )
    	return bRes;
	else
	{
		DdNode * bF0,   * bF1;
		DdNode * bPos0, * bPos1;
		DdNode * bNeg0, * bNeg1;
		DdNode * bRes0, * bRes1; 

		if ( bFR != bF ) // bF is complemented 
		{
			bF0 = Cudd_Not( cuddE(bFR) );
			bF1 = Cudd_Not( cuddT(bFR) );
		}
		else
		{
			bF0 = cuddE(bFR);
			bF1 = cuddT(bFR);
		}


		bPos0  = extraBddSpaceFromFunctionNeg( dd, bF0 );
		if ( bPos0 == NULL )
			return NULL;
		cuddRef( bPos0 );

		bPos1  = extraBddSpaceFromFunctionNeg( dd, bF1 );
		if ( bPos1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bPos0 );
			return NULL;
		}
		cuddRef( bPos1 );

		bRes0  = cuddBddAndRecur( dd, bPos0, bPos1 );
		if ( bRes0 == NULL )
		{
			Cudd_RecursiveDeref( dd, bPos0 );
			Cudd_RecursiveDeref( dd, bPos1 );
			return NULL;
		}
		cuddRef( bRes0 );
		Cudd_RecursiveDeref( dd, bPos0 );
		Cudd_RecursiveDeref( dd, bPos1 );


		bNeg0  = extraBddSpaceFromFunctionPos( dd, bF0 );
		if ( bNeg0 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			return NULL;
		}
		cuddRef( bNeg0 );

		bNeg1  = extraBddSpaceFromFunctionPos( dd, bF1 );
		if ( bNeg1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bNeg0 );
			return NULL;
		}
		cuddRef( bNeg1 );

		bRes1  = cuddBddAndRecur( dd, bNeg0, bNeg1 );
		if ( bRes1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bNeg0 );
			Cudd_RecursiveDeref( dd, bNeg1 );
			return NULL;
		}
		cuddRef( bRes1 );
		Cudd_RecursiveDeref( dd, bNeg0 );
		Cudd_RecursiveDeref( dd, bNeg1 );


		// consider the case when Res0 and Res1 are the same node 
		if ( bRes0 == bRes1 )
			bRes = bRes1;
		// consider the case when Res1 is complemented 
		else if ( Cudd_IsComplement(bRes1) ) 
		{
			bRes = cuddUniqueInter( dd, bFR->index, Cudd_Not(bRes1), Cudd_Not(bRes0) );
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
			bRes = Cudd_Not(bRes);
		} 
		else 
		{
			bRes = cuddUniqueInter( dd, bFR->index, bRes1, bRes0 );
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
		}
		cuddDeref( bRes0 );
		cuddDeref( bRes1 );

		cuddCacheInsert1( dd, extraBddSpaceFromFunctionNeg, bF, bRes );
		return bRes;
	}
}
Example #18
0
/**Function********************************************************************

  Synopsis    [Performs the recursive steps of Extra_bddSpaceFromFunction.]

  Description []

  SideEffects []

  SeeAlso     []

******************************************************************************/
DdNode * extraBddSpaceFromFunction( DdManager * dd, DdNode * bF, DdNode * bG )
{
	DdNode * bRes;
	DdNode * bFR, * bGR;

	bFR = Cudd_Regular( bF ); 
	bGR = Cudd_Regular( bG ); 
	if ( cuddIsConstant(bFR) )
	{
		if ( bF == bG )
			return b1;
		else 
			return b0;
	}
	if ( cuddIsConstant(bGR) )
		return b0;
	// both bFunc and bCore are not constants

	// the operation is commutative - normalize the problem
	if ( (unsigned)(ABC_PTRUINT_T)bF > (unsigned)(ABC_PTRUINT_T)bG )
		return extraBddSpaceFromFunction(dd, bG, bF);


    if ( (bRes = cuddCacheLookup2(dd, extraBddSpaceFromFunction, bF, bG)) )
    	return bRes;
	else
	{
		DdNode * bF0, * bF1;
		DdNode * bG0, * bG1;
		DdNode * bTemp1, * bTemp2;
		DdNode * bRes0, * bRes1;
		int LevelF, LevelG;
		int index;

		LevelF = dd->perm[bFR->index];
		LevelG = dd->perm[bGR->index];
		if ( LevelF <= LevelG )
		{
			index = dd->invperm[LevelF];
			if ( bFR != bF )
			{
				bF0 = Cudd_Not( cuddE(bFR) );
				bF1 = Cudd_Not( cuddT(bFR) );
			}
			else
			{
				bF0 = cuddE(bFR);
				bF1 = cuddT(bFR);
			}
		}
		else
		{
			index = dd->invperm[LevelG];
			bF0 = bF1 = bF;
		}

		if ( LevelG <= LevelF )
		{
			if ( bGR != bG )
			{
				bG0 = Cudd_Not( cuddE(bGR) );
				bG1 = Cudd_Not( cuddT(bGR) );
			}
			else
			{
				bG0 = cuddE(bGR);
				bG1 = cuddT(bGR);
			}
		}
		else
			bG0 = bG1 = bG;

		bTemp1 = extraBddSpaceFromFunction( dd, bF0, bG0 );
		if ( bTemp1 == NULL ) 
			return NULL;
		cuddRef( bTemp1 );

		bTemp2 = extraBddSpaceFromFunction( dd, bF1, bG1 );
		if ( bTemp2 == NULL ) 
		{
			Cudd_RecursiveDeref( dd, bTemp1 );
			return NULL;
		}
		cuddRef( bTemp2 );


		bRes0  = cuddBddAndRecur( dd, bTemp1, bTemp2 );
		if ( bRes0 == NULL )
		{
			Cudd_RecursiveDeref( dd, bTemp1 );
			Cudd_RecursiveDeref( dd, bTemp2 );
			return NULL;
		}
		cuddRef( bRes0 );
		Cudd_RecursiveDeref( dd, bTemp1 );
		Cudd_RecursiveDeref( dd, bTemp2 );


		bTemp1  = extraBddSpaceFromFunction( dd, bF0, bG1 );
		if ( bTemp1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			return NULL;
		}
		cuddRef( bTemp1 );

		bTemp2  = extraBddSpaceFromFunction( dd, bF1, bG0 );
		if ( bTemp2 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bTemp1 );
			return NULL;
		}
		cuddRef( bTemp2 );

		bRes1  = cuddBddAndRecur( dd, bTemp1, bTemp2 );
		if ( bRes1 == NULL )
		{
			Cudd_RecursiveDeref( dd, bRes0 );
			Cudd_RecursiveDeref( dd, bTemp1 );
			Cudd_RecursiveDeref( dd, bTemp2 );
			return NULL;
		}
		cuddRef( bRes1 );
		Cudd_RecursiveDeref( dd, bTemp1 );
		Cudd_RecursiveDeref( dd, bTemp2 );



		// consider the case when Res0 and Res1 are the same node 
		if ( bRes0 == bRes1 )
			bRes = bRes1;
		// consider the case when Res1 is complemented 
		else if ( Cudd_IsComplement(bRes1) ) 
		{
			bRes = cuddUniqueInter(dd, index, Cudd_Not(bRes1), Cudd_Not(bRes0));
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
			bRes = Cudd_Not(bRes);
		} 
		else 
		{
			bRes = cuddUniqueInter( dd, index, bRes1, bRes0 );
			if ( bRes == NULL ) 
			{
				Cudd_RecursiveDeref(dd,bRes0);
				Cudd_RecursiveDeref(dd,bRes1);
				return NULL;
			}
		}
		cuddDeref( bRes0 );
		cuddDeref( bRes1 );
			
		// insert the result into cache 
		cuddCacheInsert2(dd, extraBddSpaceFromFunction, bF, bG, bRes);
		return bRes;
	}
}  /* end of extraBddSpaceFromFunction */
Example #19
0
/**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 */
Example #20
0
/**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       *one, *zero, *res;
    DdNode       *r, *Fv, *Fnv, *Gv, *Gnv, *H, *Hv, *Hnv, *t, *e;
    unsigned int topf, topg, toph, v;
    int          index = -1;
    int          comple;

    statLine(dd);
    /* Terminal cases. */

    /* One variable cases. */
    if (f == (one = DD_ONE(dd)))        /* ITE(1,G,H) = G */
        return(g);
    
    if (f == (zero = Cudd_Not(one)))    /* ITE(0,G,H) = H */
        return(h);
    
    /* From now on, f is known not to be a constant. */
    if (g == one || f == g) {   /* ITE(F,F,H) = ITE(F,1,H) = F + H */
        if (h == zero) {        /* ITE(F,1,0) = F */
            return(f);
        } else {
            res = cuddBddAndRecur(dd,Cudd_Not(f),Cudd_Not(h));
            return(Cudd_NotCond(res,res != NULL));
        }
    } else if (g == zero || f == Cudd_Not(g)) { /* ITE(F,!F,H) = ITE(F,0,H) = !F * H */
        if (h == one) {         /* ITE(F,0,1) = !F */
            return(Cudd_Not(f));
        } else {
            res = cuddBddAndRecur(dd,Cudd_Not(f),h);
            return(res);
        }
    }
    if (h == zero || f == h) {    /* ITE(F,G,F) = ITE(F,G,0) = F * G */
        res = cuddBddAndRecur(dd,f,g);
        return(res);
    } else if (h == one || f == Cudd_Not(h)) { /* ITE(F,G,!F) = ITE(F,G,1) = !F + G */
        res = cuddBddAndRecur(dd,f,Cudd_Not(g));
        return(Cudd_NotCond(res,res != NULL));
    }

    /* Check remaining one 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,1,0), v < top(G,H). */
    if (topf < v && cuddT(f) == one && cuddE(f) == zero) {
        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 */
Example #21
0
/**Function********************************************************************

  Synopsis    [Performs a recursive step of Extra_bddReduceVarSet.]

  Description [Returns the set of all variables in the given set that are not in the 
  support of the given function.]

  SideEffects []

  SeeAlso     []

******************************************************************************/
DdNode * extraBddReduceVarSet( 
  DdManager * dd,    /* the DD manager */
  DdNode * bVars,    /* the set of variables to be reduced */
  DdNode * bF)       /* the function whose support is used for reduction */
{
    DdNode * bRes;
    DdNode * bFR = Cudd_Regular(bF);

    if ( cuddIsConstant(bFR) || bVars == b1 )
        return bVars;

    if ( (bRes = cuddCacheLookup2(dd, extraBddReduceVarSet, bVars, bF)) )
        return bRes;
    else
    {
        DdNode * bF0, * bF1;             
        DdNode * bVarsThis, * bVarsLower, * bTemp;
        int LevelF;

        // if LevelF is below LevelV, scroll through the vars in bVars 
        LevelF = dd->perm[bFR->index];
        for ( bVarsThis = bVars; LevelF > cuddI(dd,bVarsThis->index); bVarsThis = cuddT(bVarsThis) );
        // scroll also through the current var, because it should be not be added
        if ( LevelF == cuddI(dd,bVarsThis->index) )
            bVarsLower = cuddT(bVarsThis);
        else
            bVarsLower = bVarsThis;

        // cofactor the function
        if ( bFR != bF ) // bFunc is complemented 
        {
            bF0 = Cudd_Not( cuddE(bFR) );
            bF1 = Cudd_Not( cuddT(bFR) );
        }
        else
        {
            bF0 = cuddE(bFR);
            bF1 = cuddT(bFR);
        }

        // solve subproblems
        bRes = extraBddReduceVarSet( dd, bVarsLower, bF0 );
        if ( bRes == NULL ) 
            return NULL;
        cuddRef( bRes );

        bRes = extraBddReduceVarSet( dd, bTemp = bRes, bF1 );
        if ( bRes == NULL ) 
        {
            Cudd_RecursiveDeref( dd, bTemp );
            return NULL;
        }
        cuddRef( bRes );
        Cudd_RecursiveDeref( dd, bTemp );

        // the current var should not be added
        // add the skipped vars
        if ( bVarsThis != bVars )
        {
            DdNode * bVarsExtra;

            // extract the skipped variables
            bVarsExtra = cuddBddExistAbstractRecur( dd, bVars, bVarsThis );
            if ( bVarsExtra == NULL )
            {
                Cudd_RecursiveDeref( dd, bRes );
                return NULL;
            }
            cuddRef( bVarsExtra );

            // add these variables
            bRes = cuddBddAndRecur( dd, bTemp = bRes, bVarsExtra );
            if ( bRes == NULL ) 
            {
                Cudd_RecursiveDeref( dd, bTemp );
                Cudd_RecursiveDeref( dd, bVarsExtra );
                return NULL;
            }
            cuddRef( bRes );
            Cudd_RecursiveDeref( dd, bTemp );
            Cudd_RecursiveDeref( dd, bVarsExtra );
        }
        cuddDeref( bRes );

        cuddCacheInsert2( dd, extraBddReduceVarSet, bVars, bF, bRes );
        return bRes;
    }
}   /* end of extraBddReduceVarSet */
Example #22
0
/**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 *one, *r, *t, *e;
    unsigned int topf, topg, index;

    statLine(manager);
    one = DD_ONE(manager);

    /* Terminal cases. */
    F = Cudd_Regular(f);
    G = Cudd_Regular(g);
    if (F == G) {
        if (f == g) return(f);
        else return(Cudd_Not(one));
    }
    if (F == one) {
        if (f == one) return(g);
        else return(f);
    }
    if (G == one) {
        if (g == one) return(f);
        else return(g);
    }

    /* At this point f and g are not constant. */
    if (cuddF2L(f) > cuddF2L(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);
    }

    if ( manager->TimeStop && Abc_Clock() > manager->TimeStop )
        return NULL;

    /* 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 */