Beispiel #1
0
/**Function********************************************************************

  Synopsis    [Performs the recursive step of Cudd_zddPrintCover.]

  Description []

  SideEffects [None]

  SeeAlso     []

******************************************************************************/
static void
zddPrintCoverAux(
  DdManager * zdd /* manager */,
  DdNode * node /* current node */,
  int  level /* depth in the recursion */,
  int * list /* current recursion path */)
{
    DdNode	*Nv, *Nnv;
    int		i, v;
    DdNode	*base = DD_ONE(zdd);

    if (Cudd_IsConstant(node)) {
	if (node == base) {
	    /* Check for missing variable. */
	    if (level != zdd->sizeZ) {
		list[zdd->invpermZ[level]] = 0;
		zddPrintCoverAux(zdd, node, level + 1, list);
		return;
	    }
	    /* Terminal case: Print one cube based on the current recursion
	    ** path.
	    */
	    for (i = 0; i < zdd->sizeZ; i += 2) {
		v = list[i] * 4 + list[i+1];
		if (v == 0)
		    (void) fprintf(zdd->out,"-");
		else if (v == 4)
		    (void) fprintf(zdd->out,"1");
		else if (v == 1)
		    (void) fprintf(zdd->out,"0");
		else
		    (void) fprintf(zdd->out,"@"); /* should never happen */
	    }
	    (void) fprintf(zdd->out," 1\n");
	}
    } else {
	/* Check for missing variable. */
	if (level != cuddIZ(zdd,node->index)) {
	    list[zdd->invpermZ[level]] = 0;
	    zddPrintCoverAux(zdd, node, level + 1, list);
	    return;
	}

	Nnv = cuddE(node);
	Nv = cuddT(node);
	if (Nv == Nnv) {
	    list[node->index] = 2;
	    zddPrintCoverAux(zdd, Nnv, level + 1, list);
	    return;
	}

	list[node->index] = 1;
	zddPrintCoverAux(zdd, Nv, level + 1, list);
	list[node->index] = 0;
	zddPrintCoverAux(zdd, Nnv, level + 1, list);
    }
    return;

} /* end of zddPrintCoverAux */
Beispiel #2
0
/**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 */
Beispiel #3
0
/**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 */