summaryrefslogtreecommitdiffstats
path: root/src/bdd/cudd/cuddAndAbs.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/bdd/cudd/cuddAndAbs.c')
-rw-r--r--src/bdd/cudd/cuddAndAbs.c306
1 files changed, 306 insertions, 0 deletions
diff --git a/src/bdd/cudd/cuddAndAbs.c b/src/bdd/cudd/cuddAndAbs.c
new file mode 100644
index 00000000..3a6ce85f
--- /dev/null
+++ b/src/bdd/cudd/cuddAndAbs.c
@@ -0,0 +1,306 @@
+/**CFile***********************************************************************
+
+ FileName [cuddAndAbs.c]
+
+ PackageName [cudd]
+
+ Synopsis [Combined AND and existential abstraction for BDDs]
+
+ Description [External procedures included in this module:
+ <ul>
+ <li> Cudd_bddAndAbstract()
+ </ul>
+ Internal procedures included in this module:
+ <ul>
+ <li> cuddBddAndAbstractRecur()
+ </ul>]
+
+ Author [Fabio Somenzi]
+
+ Copyright [This file was created at the University of Colorado at
+ Boulder. The University of Colorado at Boulder makes no warranty
+ about the suitability of this software for any purpose. It is
+ presented on an AS IS basis.]
+
+******************************************************************************/
+
+#include "util.h"
+#include "cuddInt.h"
+
+
+/*---------------------------------------------------------------------------*/
+/* Constant declarations */
+/*---------------------------------------------------------------------------*/
+
+
+/*---------------------------------------------------------------------------*/
+/* Stucture declarations */
+/*---------------------------------------------------------------------------*/
+
+
+/*---------------------------------------------------------------------------*/
+/* Type declarations */
+/*---------------------------------------------------------------------------*/
+
+
+/*---------------------------------------------------------------------------*/
+/* Variable declarations */
+/*---------------------------------------------------------------------------*/
+
+#ifndef lint
+static char rcsid[] DD_UNUSED = "$Id: cuddAndAbs.c,v 1.1.1.1 2003/02/24 22:23:51 wjiang Exp $";
+#endif
+
+
+/*---------------------------------------------------------------------------*/
+/* Macro declarations */
+/*---------------------------------------------------------------------------*/
+
+
+/**AutomaticStart*************************************************************/
+
+/*---------------------------------------------------------------------------*/
+/* Static function prototypes */
+/*---------------------------------------------------------------------------*/
+
+
+/**AutomaticEnd***************************************************************/
+
+
+/*---------------------------------------------------------------------------*/
+/* Definition of exported functions */
+/*---------------------------------------------------------------------------*/
+
+
+/**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.
+ Cudd_bddAndAbstract implements the semiring matrix multiplication
+ algorithm for the boolean semiring.]
+
+ SideEffects [None]
+
+ SeeAlso [Cudd_addMatrixMultiply Cudd_addTriangle Cudd_bddAnd]
+
+******************************************************************************/
+DdNode *
+Cudd_bddAndAbstract(
+ DdManager * manager,
+ DdNode * f,
+ DdNode * g,
+ DdNode * cube)
+{
+ DdNode *res;
+
+ do {
+ manager->reordered = 0;
+ res = cuddBddAndAbstractRecur(manager, f, g, cube);
+ } while (manager->reordered == 1);
+ return(res);
+
+} /* end of Cudd_bddAndAbstract */
+
+
+/*---------------------------------------------------------------------------*/
+/* Definition of internal functions */
+/*---------------------------------------------------------------------------*/
+
+
+/**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 */
+
+
+/*---------------------------------------------------------------------------*/
+/* Definition of static functions */
+/*---------------------------------------------------------------------------*/
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-30 22:03:40 +0000