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/**
@file
@ingroup cudd
@brief Translation from %BDD to %ADD and vice versa and transfer
between different managers.
@author Fabio Somenzi
@copyright@parblock
Copyright (c) 1995-2015, Regents of the University of Colorado
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
Neither the name of the University of Colorado nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
@endparblock
*/
#include "util.h"
#include "cuddInt.h"
/*---------------------------------------------------------------------------*/
/* Constant declarations */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Stucture declarations */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Type declarations */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Variable declarations */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Macro declarations */
/*---------------------------------------------------------------------------*/
/** \cond */
/*---------------------------------------------------------------------------*/
/* Static function prototypes */
/*---------------------------------------------------------------------------*/
static DdNode * addBddDoThreshold (DdManager *dd, DdNode *f, DdNode *val);
static DdNode * addBddDoStrictThreshold (DdManager *dd, DdNode *f, DdNode *val);
static DdNode * addBddDoInterval (DdManager *dd, DdNode *f, DdNode *l, DdNode *u);
static DdNode * addBddDoIthBit (DdManager *dd, DdNode *f, DdNode *index);
static DdNode * ddBddToAddRecur (DdManager *dd, DdNode *B);
static DdNode * cuddBddTransferRecur (DdManager *ddS, DdManager *ddD, DdNode *f, st_table *table);
/** \endcond */
/*---------------------------------------------------------------------------*/
/* Definition of exported functions */
/*---------------------------------------------------------------------------*/
/**
@brief Converts an %ADD to a %BDD.
@details Replaces all discriminants greater than or equal to value
with 1, and all other discriminants with 0.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_addBddInterval Cudd_addBddPattern Cudd_BddToAdd
Cudd_addBddStrictThreshold
*/
DdNode *
Cudd_addBddThreshold(
DdManager * dd,
DdNode * f,
CUDD_VALUE_TYPE value)
{
DdNode *res;
DdNode *val;
val = cuddUniqueConst(dd,value);
if (val == NULL) return(NULL);
cuddRef(val);
do {
dd->reordered = 0;
res = addBddDoThreshold(dd, f, val);
} while (dd->reordered == 1);
if (res == NULL) {
Cudd_RecursiveDeref(dd, val);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, val);
cuddDeref(res);
return(res);
} /* end of Cudd_addBddThreshold */
/**
@brief Converts an %ADD to a %BDD.
@details Replaces all discriminants STRICTLY greater than value with
1, and all other discriminants with 0.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_addBddInterval Cudd_addBddPattern Cudd_BddToAdd
Cudd_addBddThreshold
*/
DdNode *
Cudd_addBddStrictThreshold(
DdManager * dd,
DdNode * f,
CUDD_VALUE_TYPE value)
{
DdNode *res;
DdNode *val;
val = cuddUniqueConst(dd,value);
if (val == NULL) return(NULL);
cuddRef(val);
do {
dd->reordered = 0;
res = addBddDoStrictThreshold(dd, f, val);
} while (dd->reordered == 1);
if (res == NULL) {
Cudd_RecursiveDeref(dd, val);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, val);
cuddDeref(res);
return(res);
} /* end of Cudd_addBddStrictThreshold */
/**
@brief Converts an %ADD to a %BDD.
@details Replaces all discriminants greater than or equal to lower
and less than or equal to upper with 1, and all other discriminants
with 0.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_addBddThreshold Cudd_addBddStrictThreshold
Cudd_addBddPattern Cudd_BddToAdd
*/
DdNode *
Cudd_addBddInterval(
DdManager * dd,
DdNode * f,
CUDD_VALUE_TYPE lower,
CUDD_VALUE_TYPE upper)
{
DdNode *res;
DdNode *l;
DdNode *u;
/* Create constant nodes for the interval bounds, so that we can use
** the global cache.
*/
l = cuddUniqueConst(dd,lower);
if (l == NULL) return(NULL);
cuddRef(l);
u = cuddUniqueConst(dd,upper);
if (u == NULL) {
Cudd_RecursiveDeref(dd,l);
return(NULL);
}
cuddRef(u);
do {
dd->reordered = 0;
res = addBddDoInterval(dd, f, l, u);
} while (dd->reordered == 1);
if (res == NULL) {
Cudd_RecursiveDeref(dd, l);
Cudd_RecursiveDeref(dd, u);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, l);
Cudd_RecursiveDeref(dd, u);
cuddDeref(res);
return(res);
} /* end of Cudd_addBddInterval */
/**
@brief Converts an %ADD to a %BDD by extracting the i-th bit from
the leaves.
@details Converts an %ADD to a %BDD by replacing all
discriminants whose i-th bit is equal to 1 with 1, and all other
discriminants with 0. The i-th bit refers to the integer
representation of the leaf value. If the value has a fractional
part, it is ignored. Repeated calls to this procedure allow one to
transform an integer-valued %ADD into an array of BDDs, one for each
bit of the leaf values.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_addBddInterval Cudd_addBddPattern Cudd_BddToAdd
*/
DdNode *
Cudd_addBddIthBit(
DdManager * dd,
DdNode * f,
int bit)
{
DdNode *res;
DdNode *index;
index = cuddUniqueConst(dd,(CUDD_VALUE_TYPE) bit);
if (index == NULL) return(NULL);
cuddRef(index);
do {
dd->reordered = 0;
res = addBddDoIthBit(dd, f, index);
} while (dd->reordered == 1);
if (res == NULL) {
Cudd_RecursiveDeref(dd, index);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(dd, index);
cuddDeref(res);
return(res);
} /* end of Cudd_addBddIthBit */
/**
@brief Converts a %BDD to a 0-1 %ADD.
@return a pointer to the resulting %ADD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_addBddPattern Cudd_addBddThreshold Cudd_addBddInterval
Cudd_addBddStrictThreshold
*/
DdNode *
Cudd_BddToAdd(
DdManager * dd,
DdNode * B)
{
DdNode *res;
do {
dd->reordered = 0;
res = ddBddToAddRecur(dd, B);
} while (dd->reordered ==1);
return(res);
} /* end of Cudd_BddToAdd */
/**
@brief Converts an %ADD to a %BDD.
@details Replaces all discriminants different from 0 with 1.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
@see Cudd_BddToAdd Cudd_addBddThreshold Cudd_addBddInterval
Cudd_addBddStrictThreshold
*/
DdNode *
Cudd_addBddPattern(
DdManager * dd,
DdNode * f)
{
DdNode *res;
do {
dd->reordered = 0;
res = cuddAddBddDoPattern(dd, f);
} while (dd->reordered == 1);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(res);
} /* end of Cudd_addBddPattern */
/**
@brief Convert a %BDD from a manager to another one.
@details The orders of the variables in the two managers may be
different.
@return a pointer to the %BDD in the destination manager if
successful; NULL otherwise.
@sideeffect None
*/
DdNode *
Cudd_bddTransfer(
DdManager * ddSource,
DdManager * ddDestination,
DdNode * f)
{
DdNode *res;
do {
ddDestination->reordered = 0;
res = cuddBddTransfer(ddSource, ddDestination, f);
} while (ddDestination->reordered == 1);
if (ddDestination->errorCode == CUDD_TIMEOUT_EXPIRED &&
ddDestination->timeoutHandler) {
ddDestination->timeoutHandler(ddDestination, ddDestination->tohArg);
}
return(res);
} /* end of Cudd_bddTransfer */
/*---------------------------------------------------------------------------*/
/* Definition of internal functions */
/*---------------------------------------------------------------------------*/
/**
@brief Convert a %BDD from a manager to another one.
@return a pointer to the %BDD in the destination manager if
successful; NULL otherwise.
@sideeffect None
@see Cudd_bddTransfer
*/
DdNode *
cuddBddTransfer(
DdManager * ddS,
DdManager * ddD,
DdNode * f)
{
DdNode *res;
st_table *table = NULL;
st_generator *gen = NULL;
DdNode *key, *value;
table = st_init_table(st_ptrcmp,st_ptrhash);
if (table == NULL) goto failure;
res = cuddBddTransferRecur(ddS, ddD, f, table);
if (res != NULL) cuddRef(res);
/* Dereference all elements in the table and dispose of the table.
** This must be done also if res is NULL to avoid leaks in case of
** reordering. */
gen = st_init_gen(table);
if (gen == NULL) goto failure;
while (st_gen(gen, (void **) &key, (void **) &value)) {
Cudd_RecursiveDeref(ddD, value);
}
st_free_gen(gen); gen = NULL;
st_free_table(table); table = NULL;
if (res != NULL) cuddDeref(res);
return(res);
failure:
/* No need to free gen because it is always NULL here. */
if (table != NULL) st_free_table(table);
return(NULL);
} /* end of cuddBddTransfer */
/**
@brief Performs the recursive step for Cudd_addBddPattern.
@return a pointer to the resulting %BDD if successful; NULL
otherwise.
@sideeffect None
*/
DdNode *
cuddAddBddDoPattern(
DdManager * dd,
DdNode * f)
{
DdNode *res, *T, *E;
DdNode *fv, *fvn;
unsigned int v;
statLine(dd);
/* Check terminal case. */
if (cuddIsConstant(f)) {
return(Cudd_NotCond(DD_ONE(dd),f == DD_ZERO(dd)));
}
/* Check cache. */
res = cuddCacheLookup1(dd,Cudd_addBddPattern,f);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive step. */
v = f->index;
fv = cuddT(f); fvn = cuddE(f);
T = cuddAddBddDoPattern(dd,fv);
if (T == NULL) return(NULL);
cuddRef(T);
E = cuddAddBddDoPattern(dd,fvn);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
if (Cudd_IsComplement(T)) {
res = (T == E) ? Cudd_Not(T) : cuddUniqueInter(dd,v,Cudd_Not(T),Cudd_Not(E));
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = (T == E) ? T : cuddUniqueInter(dd,v,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert1(dd,Cudd_addBddPattern,f,res);
return(res);
} /* end of cuddAddBddDoPattern */
/*---------------------------------------------------------------------------*/
/* Definition of static functions */
/*---------------------------------------------------------------------------*/
/**
@brief Performs the recursive step for Cudd_addBddThreshold.
@return a pointer to the %BDD if successful; NULL otherwise.
@sideeffect None
@see addBddDoStrictThreshold
*/
static DdNode *
addBddDoThreshold(
DdManager * dd,
DdNode * f,
DdNode * val)
{
DdNode *res, *T, *E;
DdNode *fv, *fvn;
unsigned int v;
statLine(dd);
/* Check terminal case. */
if (cuddIsConstant(f)) {
return(Cudd_NotCond(DD_ONE(dd),cuddV(f) < cuddV(val)));
}
/* Check cache. */
res = cuddCacheLookup2(dd,addBddDoThreshold,f,val);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive step. */
v = f->index;
fv = cuddT(f); fvn = cuddE(f);
T = addBddDoThreshold(dd,fv,val);
if (T == NULL) return(NULL);
cuddRef(T);
E = addBddDoThreshold(dd,fvn,val);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
if (Cudd_IsComplement(T)) {
res = (T == E) ? Cudd_Not(T) : cuddUniqueInter(dd,v,Cudd_Not(T),Cudd_Not(E));
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = (T == E) ? T : cuddUniqueInter(dd,v,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert2(dd,addBddDoThreshold,f,val,res);
return(res);
} /* end of addBddDoThreshold */
/**
@brief Performs the recursive step for Cudd_addBddStrictThreshold.
@return a pointer to the %BDD if successful; NULL otherwise.
@sideeffect None
@see addBddDoThreshold
*/
static DdNode *
addBddDoStrictThreshold(
DdManager * dd,
DdNode * f,
DdNode * val)
{
DdNode *res, *T, *E;
DdNode *fv, *fvn;
unsigned int v;
statLine(dd);
/* Check terminal case. */
if (cuddIsConstant(f)) {
return(Cudd_NotCond(DD_ONE(dd),cuddV(f) <= cuddV(val)));
}
/* Check cache. */
res = cuddCacheLookup2(dd,addBddDoStrictThreshold,f,val);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive step. */
v = f->index;
fv = cuddT(f); fvn = cuddE(f);
T = addBddDoStrictThreshold(dd,fv,val);
if (T == NULL) return(NULL);
cuddRef(T);
E = addBddDoStrictThreshold(dd,fvn,val);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
if (Cudd_IsComplement(T)) {
res = (T == E) ? Cudd_Not(T) : cuddUniqueInter(dd,v,Cudd_Not(T),Cudd_Not(E));
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = (T == E) ? T : cuddUniqueInter(dd,v,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert2(dd,addBddDoStrictThreshold,f,val,res);
return(res);
} /* end of addBddDoStrictThreshold */
/**
@brief Performs the recursive step for Cudd_addBddInterval.
@return a pointer to the %BDD if successful; NULL otherwise.
@sideeffect None
@see addBddDoThreshold addBddDoStrictThreshold
*/
static DdNode *
addBddDoInterval(
DdManager * dd,
DdNode * f,
DdNode * l,
DdNode * u)
{
DdNode *res, *T, *E;
DdNode *fv, *fvn;
unsigned int v;
statLine(dd);
/* Check terminal case. */
if (cuddIsConstant(f)) {
return(Cudd_NotCond(DD_ONE(dd),cuddV(f) < cuddV(l) || cuddV(f) > cuddV(u)));
}
/* Check cache. */
res = cuddCacheLookup(dd,DD_ADD_BDD_DO_INTERVAL_TAG,f,l,u);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive step. */
v = f->index;
fv = cuddT(f); fvn = cuddE(f);
T = addBddDoInterval(dd,fv,l,u);
if (T == NULL) return(NULL);
cuddRef(T);
E = addBddDoInterval(dd,fvn,l,u);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
if (Cudd_IsComplement(T)) {
res = (T == E) ? Cudd_Not(T) : cuddUniqueInter(dd,v,Cudd_Not(T),Cudd_Not(E));
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = (T == E) ? T : cuddUniqueInter(dd,v,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert(dd,DD_ADD_BDD_DO_INTERVAL_TAG,f,l,u,res);
return(res);
} /* end of addBddDoInterval */
/**
@brief Performs the recursive step for Cudd_addBddIthBit.
@return a pointer to the %BDD if successful; NULL otherwise.
@sideeffect None
*/
static DdNode *
addBddDoIthBit(
DdManager * dd,
DdNode * f,
DdNode * index)
{
DdNode *res, *T, *E;
DdNode *fv, *fvn;
int mask, value;
unsigned int v;
statLine(dd);
/* Check terminal case. */
if (cuddIsConstant(f)) {
mask = 1 << ((int) cuddV(index));
value = (int) cuddV(f);
return(Cudd_NotCond(DD_ONE(dd),(value & mask) == 0));
}
/* Check cache. */
res = cuddCacheLookup2(dd,addBddDoIthBit,f,index);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive step. */
v = f->index;
fv = cuddT(f); fvn = cuddE(f);
T = addBddDoIthBit(dd,fv,index);
if (T == NULL) return(NULL);
cuddRef(T);
E = addBddDoIthBit(dd,fvn,index);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
if (Cudd_IsComplement(T)) {
res = (T == E) ? Cudd_Not(T) : cuddUniqueInter(dd,v,Cudd_Not(T),Cudd_Not(E));
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
res = Cudd_Not(res);
} else {
res = (T == E) ? T : cuddUniqueInter(dd,v,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert2(dd,addBddDoIthBit,f,index,res);
return(res);
} /* end of addBddDoIthBit */
/**
@brief Performs the recursive step for Cudd_BddToAdd.
@return a pointer to the resulting %ADD if successful; NULL
otherwise.
@sideeffect None
*/
static DdNode *
ddBddToAddRecur(
DdManager * dd,
DdNode * B)
{
DdNode *one;
DdNode *res, *res1, *T, *E, *Bt, *Be;
int complement = 0;
statLine(dd);
one = DD_ONE(dd);
if (Cudd_IsConstantInt(B)) {
if (B == one) {
res = one;
} else {
res = DD_ZERO(dd);
}
return(res);
}
/* Check visited table */
res = cuddCacheLookup1(dd,ddBddToAddRecur,B);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
if (Cudd_IsComplement(B)) {
complement = 1;
Bt = cuddT(Cudd_Regular(B));
Be = cuddE(Cudd_Regular(B));
} else {
Bt = cuddT(B);
Be = cuddE(B);
}
T = ddBddToAddRecur(dd, Bt);
if (T == NULL) return(NULL);
cuddRef(T);
E = ddBddToAddRecur(dd, Be);
if (E == NULL) {
Cudd_RecursiveDeref(dd, T);
return(NULL);
}
cuddRef(E);
/* No need to check for T == E, because it is guaranteed not to happen. */
res = cuddUniqueInter(dd, (int) Cudd_Regular(B)->index, T, E);
if (res == NULL) {
Cudd_RecursiveDeref(dd ,T);
Cudd_RecursiveDeref(dd ,E);
return(NULL);
}
cuddDeref(T);
cuddDeref(E);
if (complement) {
cuddRef(res);
res1 = cuddAddCmplRecur(dd, res);
if (res1 == NULL) {
Cudd_RecursiveDeref(dd, res);
return(NULL);
}
cuddRef(res1);
Cudd_RecursiveDeref(dd, res);
res = res1;
cuddDeref(res);
}
/* Store result. */
cuddCacheInsert1(dd,ddBddToAddRecur,B,res);
return(res);
} /* end of ddBddToAddRecur */
/**
@brief Performs the recursive step of Cudd_bddTransfer.
@return a pointer to the result if successful; NULL otherwise.
@sideeffect None
@see cuddBddTransfer
*/
static DdNode *
cuddBddTransferRecur(
DdManager * ddS,
DdManager * ddD,
DdNode * f,
st_table * table)
{
DdNode *ft, *fe, *t, *e, *var, *res;
DdNode *one, *zero;
unsigned int index;
int comple = 0;
statLine(ddD);
one = DD_ONE(ddD);
comple = Cudd_IsComplement(f);
/* Trivial cases. */
if (Cudd_IsConstantInt(f)) return(Cudd_NotCond(one, comple));
/* Make canonical to increase the utilization of the cache. */
f = Cudd_NotCond(f,comple);
/* Now f is a regular pointer to a non-constant node. */
/* Check the cache. */
if (st_lookup(table, f, (void **) &res))
return(Cudd_NotCond(res,comple));
/* Recursive step. */
index = f->index;
ft = cuddT(f); fe = cuddE(f);
t = cuddBddTransferRecur(ddS, ddD, ft, table);
if (t == NULL) {
return(NULL);
}
cuddRef(t);
e = cuddBddTransferRecur(ddS, ddD, fe, table);
if (e == NULL) {
Cudd_RecursiveDeref(ddD, t);
return(NULL);
}
cuddRef(e);
zero = Cudd_Not(one);
var = cuddUniqueInter(ddD,index,one,zero);
if (var == NULL) {
Cudd_RecursiveDeref(ddD, t);
Cudd_RecursiveDeref(ddD, e);
return(NULL);
}
res = cuddBddIteRecur(ddD,var,t,e);
if (res == NULL) {
Cudd_RecursiveDeref(ddD, t);
Cudd_RecursiveDeref(ddD, e);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(ddD, t);
Cudd_RecursiveDeref(ddD, e);
if (st_add_direct(table, f, res) == ST_OUT_OF_MEM) {
Cudd_RecursiveDeref(ddD, res);
return(NULL);
}
return(Cudd_NotCond(res,comple));
} /* end of cuddBddTransferRecur */