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author | Alan Mishchenko <alanmi@berkeley.edu> | 2007-10-01 08:01:00 -0700 |
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committer | Alan Mishchenko <alanmi@berkeley.edu> | 2007-10-01 08:01:00 -0700 |
commit | 4812c90424dfc40d26725244723887a2d16ddfd9 (patch) | |
tree | b32ace96e7e2d84d586e09ba605463b6f49c3271 /src/bdd/cudd/cuddZddSetop.c | |
parent | e54d9691616b9a0326e2fdb3156bb4eeb8abfcd7 (diff) | |
download | abc-4812c90424dfc40d26725244723887a2d16ddfd9.tar.gz abc-4812c90424dfc40d26725244723887a2d16ddfd9.tar.bz2 abc-4812c90424dfc40d26725244723887a2d16ddfd9.zip |
Version abc71001
Diffstat (limited to 'src/bdd/cudd/cuddZddSetop.c')
-rw-r--r-- | src/bdd/cudd/cuddZddSetop.c | 1137 |
1 files changed, 1137 insertions, 0 deletions
diff --git a/src/bdd/cudd/cuddZddSetop.c b/src/bdd/cudd/cuddZddSetop.c new file mode 100644 index 00000000..f1bd72f3 --- /dev/null +++ b/src/bdd/cudd/cuddZddSetop.c @@ -0,0 +1,1137 @@ +/**CFile*********************************************************************** + + FileName [cuddZddSetop.c] + + PackageName [cudd] + + Synopsis [Set operations on ZDDs.] + + Description [External procedures included in this module: + <ul> + <li> Cudd_zddIte() + <li> Cudd_zddUnion() + <li> Cudd_zddIntersect() + <li> Cudd_zddDiff() + <li> Cudd_zddDiffConst() + <li> Cudd_zddSubset1() + <li> Cudd_zddSubset0() + <li> Cudd_zddChange() + </ul> + Internal procedures included in this module: + <ul> + <li> cuddZddIte() + <li> cuddZddUnion() + <li> cuddZddIntersect() + <li> cuddZddDiff() + <li> cuddZddChangeAux() + <li> cuddZddSubset1() + <li> cuddZddSubset0() + </ul> + Static procedures included in this module: + <ul> + <li> zdd_subset1_aux() + <li> zdd_subset0_aux() + <li> zddVarToConst() + </ul> + ] + + SeeAlso [] + + Author [Hyong-Kyoon Shin, In-Ho Moon] + + 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_hack.h" +#include "cuddInt.h" + +/*---------------------------------------------------------------------------*/ +/* Constant declarations */ +/*---------------------------------------------------------------------------*/ + + +/*---------------------------------------------------------------------------*/ +/* Stucture declarations */ +/*---------------------------------------------------------------------------*/ + + +/*---------------------------------------------------------------------------*/ +/* Type declarations */ +/*---------------------------------------------------------------------------*/ + + +/*---------------------------------------------------------------------------*/ +/* Variable declarations */ +/*---------------------------------------------------------------------------*/ + +#ifndef lint +static char rcsid[] DD_UNUSED = "$Id: cuddZddSetop.c,v 1.1.1.1 2003/02/24 22:23:54 wjiang Exp $"; +#endif + +/*---------------------------------------------------------------------------*/ +/* Macro declarations */ +/*---------------------------------------------------------------------------*/ + + +/**AutomaticStart*************************************************************/ + +/*---------------------------------------------------------------------------*/ +/* Static function prototypes */ +/*---------------------------------------------------------------------------*/ + +static DdNode * zdd_subset1_aux ARGS((DdManager *zdd, DdNode *P, DdNode *zvar)); +static DdNode * zdd_subset0_aux ARGS((DdManager *zdd, DdNode *P, DdNode *zvar)); +static void zddVarToConst ARGS((DdNode *f, DdNode **gp, DdNode **hp, DdNode *base, DdNode *empty)); + +/**AutomaticEnd***************************************************************/ + + +/*---------------------------------------------------------------------------*/ +/* Definition of exported functions */ +/*---------------------------------------------------------------------------*/ + + +/**Function******************************************************************** + + Synopsis [Computes the ITE of three ZDDs.] + + Description [Computes the ITE of three ZDDs. Returns a pointer to the + result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +Cudd_zddIte( + DdManager * dd, + DdNode * f, + DdNode * g, + DdNode * h) +{ + DdNode *res; + + do { + dd->reordered = 0; + res = cuddZddIte(dd, f, g, h); + } while (dd->reordered == 1); + return(res); + +} /* end of Cudd_zddIte */ + + +/**Function******************************************************************** + + Synopsis [Computes the union of two ZDDs.] + + Description [Computes the union of two ZDDs. Returns a pointer to the + result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +Cudd_zddUnion( + DdManager * dd, + DdNode * P, + DdNode * Q) +{ + DdNode *res; + + do { + dd->reordered = 0; + res = cuddZddUnion(dd, P, Q); + } while (dd->reordered == 1); + return(res); + +} /* end of Cudd_zddUnion */ + + +/**Function******************************************************************** + + Synopsis [Computes the intersection of two ZDDs.] + + Description [Computes the intersection of two ZDDs. Returns a pointer to + the result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +Cudd_zddIntersect( + DdManager * dd, + DdNode * P, + DdNode * Q) +{ + DdNode *res; + + do { + dd->reordered = 0; + res = cuddZddIntersect(dd, P, Q); + } while (dd->reordered == 1); + return(res); + +} /* end of Cudd_zddIntersect */ + + +/**Function******************************************************************** + + Synopsis [Computes the difference of two ZDDs.] + + Description [Computes the difference of two ZDDs. Returns a pointer to the + result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [Cudd_zddDiffConst] + +******************************************************************************/ +DdNode * +Cudd_zddDiff( + DdManager * dd, + DdNode * P, + DdNode * Q) +{ + DdNode *res; + + do { + dd->reordered = 0; + res = cuddZddDiff(dd, P, Q); + } while (dd->reordered == 1); + return(res); + +} /* end of Cudd_zddDiff */ + + +/**Function******************************************************************** + + Synopsis [Performs the inclusion test for ZDDs (P implies Q).] + + Description [Inclusion test for ZDDs (P implies Q). No new nodes are + generated by this procedure. Returns empty if true; + a valid pointer different from empty or DD_NON_CONSTANT otherwise.] + + SideEffects [None] + + SeeAlso [Cudd_zddDiff] + +******************************************************************************/ +DdNode * +Cudd_zddDiffConst( + DdManager * zdd, + DdNode * P, + DdNode * Q) +{ + int p_top, q_top; + DdNode *empty = DD_ZERO(zdd), *t, *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 cuddZddDiff(). */ + res = cuddCacheLookup2Zdd(table, cuddZddDiff, P, Q); + if (res != NULL) + 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) { + res = DD_NON_CONSTANT; + } else if (p_top > q_top) { + res = Cudd_zddDiffConst(zdd, P, cuddE(Q)); + } else { + t = Cudd_zddDiffConst(zdd, cuddT(P), cuddT(Q)); + if (t != empty) + res = DD_NON_CONSTANT; + else + res = Cudd_zddDiffConst(zdd, cuddE(P), cuddE(Q)); + } + + cuddCacheInsert2(table, cuddZddDiff, P, Q, res); + + return(res); + +} /* end of Cudd_zddDiffConst */ + + +/**Function******************************************************************** + + Synopsis [Computes the positive cofactor of a ZDD w.r.t. a variable.] + + Description [Computes the positive cofactor of a ZDD w.r.t. a + variable. In terms of combinations, the result is the set of all + combinations in which the variable is asserted. Returns a pointer to + the result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [Cudd_zddSubset0] + +******************************************************************************/ +DdNode * +Cudd_zddSubset1( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *r; + + do { + dd->reordered = 0; + r = cuddZddSubset1(dd, P, var); + } while (dd->reordered == 1); + + return(r); + +} /* end of Cudd_zddSubset1 */ + + +/**Function******************************************************************** + + Synopsis [Computes the negative cofactor of a ZDD w.r.t. a variable.] + + Description [Computes the negative cofactor of a ZDD w.r.t. a + variable. In terms of combinations, the result is the set of all + combinations in which the variable is negated. Returns a pointer to + the result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [Cudd_zddSubset1] + +******************************************************************************/ +DdNode * +Cudd_zddSubset0( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *r; + + do { + dd->reordered = 0; + r = cuddZddSubset0(dd, P, var); + } while (dd->reordered == 1); + + return(r); + +} /* end of Cudd_zddSubset0 */ + + +/**Function******************************************************************** + + Synopsis [Substitutes a variable with its complement in a ZDD.] + + Description [Substitutes a variable with its complement in a ZDD. + returns a pointer to the result if successful; NULL otherwise.] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +Cudd_zddChange( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *res; + + if ((unsigned int) var >= CUDD_MAXINDEX - 1) return(NULL); + + do { + dd->reordered = 0; + res = cuddZddChange(dd, P, var); + } while (dd->reordered == 1); + return(res); + +} /* end of Cudd_zddChange */ + + +/*---------------------------------------------------------------------------*/ +/* Definition of internal functions */ +/*---------------------------------------------------------------------------*/ + + +/**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_zddUnion.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +cuddZddUnion( + 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(Q); + if (Q == empty) + return(P); + if (P == Q) + return(P); + + /* Check cache */ + res = cuddCacheLookup2Zdd(table, cuddZddUnion, P, Q); + if (res != NULL) + 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 = cuddZddUnion(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) { + e = cuddZddUnion(zdd, P, cuddE(Q)); + if (e == NULL) return(NULL); + cuddRef(e); + res = cuddZddGetNode(zdd, Q->index, cuddT(Q), e); + if (res == NULL) { + Cudd_RecursiveDerefZdd(table, e); + return(NULL); + } + cuddDeref(e); + } else { + t = cuddZddUnion(zdd, cuddT(P), cuddT(Q)); + if (t == NULL) return(NULL); + cuddRef(t); + e = cuddZddUnion(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, cuddZddUnion, P, Q, res); + + return(res); + +} /* end of cuddZddUnion */ + + +/**Function******************************************************************** + + Synopsis [Performs the recursive step of Cudd_zddIntersect.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +cuddZddIntersect( + 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(empty); + if (P == Q) + return(P); + + /* Check cache. */ + res = cuddCacheLookup2Zdd(table, cuddZddIntersect, P, Q); + if (res != NULL) + 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) { + res = cuddZddIntersect(zdd, cuddE(P), Q); + if (res == NULL) return(NULL); + } else if (p_top > q_top) { + res = cuddZddIntersect(zdd, P, cuddE(Q)); + if (res == NULL) return(NULL); + } else { + t = cuddZddIntersect(zdd, cuddT(P), cuddT(Q)); + if (t == NULL) return(NULL); + cuddRef(t); + e = cuddZddIntersect(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, cuddZddIntersect, P, Q, res); + + return(res); + +} /* end of cuddZddIntersect */ + + +/**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 [Performs the recursive step of Cudd_zddChange.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +DdNode * +cuddZddChangeAux( + DdManager * zdd, + DdNode * P, + DdNode * zvar) +{ + int top_var, level; + DdNode *res, *t, *e; + DdNode *base = DD_ONE(zdd); + DdNode *empty = DD_ZERO(zdd); + + statLine(zdd); + if (P == empty) + return(empty); + if (P == base) + return(zvar); + + /* Check cache. */ + res = cuddCacheLookup2Zdd(zdd, cuddZddChangeAux, P, zvar); + if (res != NULL) + return(res); + + top_var = zdd->permZ[P->index]; + level = zdd->permZ[zvar->index]; + + if (top_var > level) { + res = cuddZddGetNode(zdd, zvar->index, P, DD_ZERO(zdd)); + if (res == NULL) return(NULL); + } else if (top_var == level) { + res = cuddZddGetNode(zdd, zvar->index, cuddE(P), cuddT(P)); + if (res == NULL) return(NULL); + } else { + t = cuddZddChangeAux(zdd, cuddT(P), zvar); + if (t == NULL) return(NULL); + cuddRef(t); + e = cuddZddChangeAux(zdd, cuddE(P), zvar); + if (e == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + return(NULL); + } + cuddRef(e); + res = cuddZddGetNode(zdd, P->index, t, e); + if (res == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + Cudd_RecursiveDerefZdd(zdd, e); + return(NULL); + } + cuddDeref(t); + cuddDeref(e); + } + + cuddCacheInsert2(zdd, cuddZddChangeAux, P, zvar, res); + + return(res); + +} /* end of cuddZddChangeAux */ + + +/**Function******************************************************************** + + Synopsis [Computes the positive cofactor of a ZDD w.r.t. a variable.] + + Description [Computes the positive cofactor of a ZDD w.r.t. a + variable. In terms of combinations, the result is the set of all + combinations in which the variable is asserted. Returns a pointer to + the result if successful; NULL otherwise. cuddZddSubset1 performs + the same function as Cudd_zddSubset1, but does not restart if + reordering has taken place. Therefore it can be called from within a + recursive procedure.] + + SideEffects [None] + + SeeAlso [cuddZddSubset0 Cudd_zddSubset1] + +******************************************************************************/ +DdNode * +cuddZddSubset1( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *zvar, *r; + DdNode *base, *empty; + + base = DD_ONE(dd); + empty = DD_ZERO(dd); + + zvar = cuddUniqueInterZdd(dd, var, base, empty); + if (zvar == NULL) { + return(NULL); + } else { + cuddRef(zvar); + r = zdd_subset1_aux(dd, P, zvar); + if (r == NULL) { + Cudd_RecursiveDerefZdd(dd, zvar); + return(NULL); + } + cuddRef(r); + Cudd_RecursiveDerefZdd(dd, zvar); + } + + cuddDeref(r); + return(r); + +} /* end of cuddZddSubset1 */ + + +/**Function******************************************************************** + + Synopsis [Computes the negative cofactor of a ZDD w.r.t. a variable.] + + Description [Computes the negative cofactor of a ZDD w.r.t. a + variable. In terms of combinations, the result is the set of all + combinations in which the variable is negated. Returns a pointer to + the result if successful; NULL otherwise. cuddZddSubset0 performs + the same function as Cudd_zddSubset0, but does not restart if + reordering has taken place. Therefore it can be called from within a + recursive procedure.] + + SideEffects [None] + + SeeAlso [cuddZddSubset1 Cudd_zddSubset0] + +******************************************************************************/ +DdNode * +cuddZddSubset0( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *zvar, *r; + DdNode *base, *empty; + + base = DD_ONE(dd); + empty = DD_ZERO(dd); + + zvar = cuddUniqueInterZdd(dd, var, base, empty); + if (zvar == NULL) { + return(NULL); + } else { + cuddRef(zvar); + r = zdd_subset0_aux(dd, P, zvar); + if (r == NULL) { + Cudd_RecursiveDerefZdd(dd, zvar); + return(NULL); + } + cuddRef(r); + Cudd_RecursiveDerefZdd(dd, zvar); + } + + cuddDeref(r); + return(r); + +} /* end of cuddZddSubset0 */ + + +/**Function******************************************************************** + + Synopsis [Substitutes a variable with its complement in a ZDD.] + + Description [Substitutes a variable with its complement in a ZDD. + returns a pointer to the result if successful; NULL + otherwise. cuddZddChange performs the same function as + Cudd_zddChange, but does not restart if reordering has taken + place. Therefore it can be called from within a recursive + procedure.] + + SideEffects [None] + + SeeAlso [Cudd_zddChange] + +******************************************************************************/ +DdNode * +cuddZddChange( + DdManager * dd, + DdNode * P, + int var) +{ + DdNode *zvar, *res; + + zvar = cuddUniqueInterZdd(dd, var, DD_ONE(dd), DD_ZERO(dd)); + if (zvar == NULL) return(NULL); + cuddRef(zvar); + + res = cuddZddChangeAux(dd, P, zvar); + if (res == NULL) { + Cudd_RecursiveDerefZdd(dd,zvar); + return(NULL); + } + cuddRef(res); + Cudd_RecursiveDerefZdd(dd,zvar); + cuddDeref(res); + return(res); + +} /* end of cuddZddChange */ + + +/*---------------------------------------------------------------------------*/ +/* Definition of static functions */ +/*---------------------------------------------------------------------------*/ + + +/**Function******************************************************************** + + Synopsis [Performs the recursive step of Cudd_zddSubset1.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static DdNode * +zdd_subset1_aux( + DdManager * zdd, + DdNode * P, + DdNode * zvar) +{ + int top_var, level; + DdNode *res, *t, *e; + DdNode *base, *empty; + + statLine(zdd); + base = DD_ONE(zdd); + empty = DD_ZERO(zdd); + + /* Check cache. */ + res = cuddCacheLookup2Zdd(zdd, zdd_subset1_aux, P, zvar); + if (res != NULL) + return(res); + + if (cuddIsConstant(P)) { + res = empty; + cuddCacheInsert2(zdd, zdd_subset1_aux, P, zvar, res); + return(res); + } + + top_var = zdd->permZ[P->index]; + level = zdd->permZ[zvar->index]; + + if (top_var > level) { + res = empty; + } else if (top_var == level) { + res = cuddT(P); + } else { + t = zdd_subset1_aux(zdd, cuddT(P), zvar); + if (t == NULL) return(NULL); + cuddRef(t); + e = zdd_subset1_aux(zdd, cuddE(P), zvar); + if (e == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + return(NULL); + } + cuddRef(e); + res = cuddZddGetNode(zdd, P->index, t, e); + if (res == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + Cudd_RecursiveDerefZdd(zdd, e); + return(NULL); + } + cuddDeref(t); + cuddDeref(e); + } + + cuddCacheInsert2(zdd, zdd_subset1_aux, P, zvar, res); + + return(res); + +} /* end of zdd_subset1_aux */ + + +/**Function******************************************************************** + + Synopsis [Performs the recursive step of Cudd_zddSubset0.] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static DdNode * +zdd_subset0_aux( + DdManager * zdd, + DdNode * P, + DdNode * zvar) +{ + int top_var, level; + DdNode *res, *t, *e; + DdNode *base, *empty; + + statLine(zdd); + base = DD_ONE(zdd); + empty = DD_ZERO(zdd); + + /* Check cache. */ + res = cuddCacheLookup2Zdd(zdd, zdd_subset0_aux, P, zvar); + if (res != NULL) + return(res); + + if (cuddIsConstant(P)) { + res = P; + cuddCacheInsert2(zdd, zdd_subset0_aux, P, zvar, res); + return(res); + } + + top_var = zdd->permZ[P->index]; + level = zdd->permZ[zvar->index]; + + if (top_var > level) { + res = P; + } + else if (top_var == level) { + res = cuddE(P); + } + else { + t = zdd_subset0_aux(zdd, cuddT(P), zvar); + if (t == NULL) return(NULL); + cuddRef(t); + e = zdd_subset0_aux(zdd, cuddE(P), zvar); + if (e == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + return(NULL); + } + cuddRef(e); + res = cuddZddGetNode(zdd, P->index, t, e); + if (res == NULL) { + Cudd_RecursiveDerefZdd(zdd, t); + Cudd_RecursiveDerefZdd(zdd, e); + return(NULL); + } + cuddDeref(t); + cuddDeref(e); + } + + cuddCacheInsert2(zdd, zdd_subset0_aux, P, zvar, res); + + return(res); + +} /* end of zdd_subset0_aux */ + + +/**Function******************************************************************** + + Synopsis [Replaces variables with constants if possible (part of + canonical form).] + + Description [] + + SideEffects [None] + + SeeAlso [] + +******************************************************************************/ +static void +zddVarToConst( + DdNode * f, + DdNode ** gp, + DdNode ** hp, + DdNode * base, + DdNode * empty) +{ + DdNode *g = *gp; + DdNode *h = *hp; + + if (f == g) { /* ITE(F,F,H) = ITE(F,1,H) = F + H */ + *gp = base; + } + + if (f == h) { /* ITE(F,G,F) = ITE(F,G,0) = F * G */ + *hp = empty; + } + +} /* end of zddVarToConst */ + |