You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
298 lines
7.8 KiB
298 lines
7.8 KiB
/**
|
|
@file
|
|
|
|
@ingroup cudd
|
|
|
|
@brief Functions to find maximum and minimum in an %ADD and to
|
|
extract the i-th bit.
|
|
|
|
@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 * addDoIthBit (DdManager *dd, DdNode *f, DdNode *index);
|
|
|
|
/** \endcond */
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of exported functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
@brief Finds the maximum discriminant of f.
|
|
|
|
@return a pointer to a constant %ADD.
|
|
|
|
@sideeffect None
|
|
|
|
*/
|
|
DdNode *
|
|
Cudd_addFindMax(
|
|
DdManager * dd,
|
|
DdNode * f)
|
|
{
|
|
DdNode *t, *e, *res;
|
|
|
|
statLine(dd);
|
|
if (cuddIsConstant(f)) {
|
|
return(f);
|
|
}
|
|
|
|
res = cuddCacheLookup1(dd,Cudd_addFindMax,f);
|
|
if (res != NULL) {
|
|
return(res);
|
|
}
|
|
|
|
checkWhetherToGiveUp(dd);
|
|
|
|
t = Cudd_addFindMax(dd,cuddT(f));
|
|
if (t == DD_PLUS_INFINITY(dd)) return(t);
|
|
|
|
e = Cudd_addFindMax(dd,cuddE(f));
|
|
|
|
res = (cuddV(t) >= cuddV(e)) ? t : e;
|
|
|
|
cuddCacheInsert1(dd,Cudd_addFindMax,f,res);
|
|
|
|
return(res);
|
|
|
|
} /* end of Cudd_addFindMax */
|
|
|
|
|
|
/**
|
|
@brief Finds the minimum discriminant of f.
|
|
|
|
@return a pointer to a constant %ADD.
|
|
|
|
@sideeffect None
|
|
|
|
*/
|
|
DdNode *
|
|
Cudd_addFindMin(
|
|
DdManager * dd,
|
|
DdNode * f)
|
|
{
|
|
DdNode *t, *e, *res;
|
|
|
|
statLine(dd);
|
|
if (cuddIsConstant(f)) {
|
|
return(f);
|
|
}
|
|
|
|
res = cuddCacheLookup1(dd,Cudd_addFindMin,f);
|
|
if (res != NULL) {
|
|
return(res);
|
|
}
|
|
|
|
checkWhetherToGiveUp(dd);
|
|
|
|
t = Cudd_addFindMin(dd,cuddT(f));
|
|
if (t == DD_MINUS_INFINITY(dd)) return(t);
|
|
|
|
e = Cudd_addFindMin(dd,cuddE(f));
|
|
|
|
res = (cuddV(t) <= cuddV(e)) ? t : e;
|
|
|
|
cuddCacheInsert1(dd,Cudd_addFindMin,f,res);
|
|
|
|
return(res);
|
|
|
|
} /* end of Cudd_addFindMin */
|
|
|
|
|
|
/**
|
|
@brief Extracts the i-th bit from an %ADD.
|
|
|
|
@details Produces an %ADD from another %ADD 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 ADDs, one for each
|
|
bit of the leaf values.
|
|
|
|
@return a pointer to the resulting %ADD if successful; NULL
|
|
otherwise.
|
|
|
|
@sideeffect None
|
|
|
|
@see Cudd_addBddIthBit
|
|
|
|
*/
|
|
DdNode *
|
|
Cudd_addIthBit(
|
|
DdManager * dd,
|
|
DdNode * f,
|
|
int bit)
|
|
{
|
|
DdNode *res;
|
|
DdNode *index;
|
|
|
|
/* Use a constant node to remember the bit, so that we can use the
|
|
** global cache.
|
|
*/
|
|
index = cuddUniqueConst(dd,(CUDD_VALUE_TYPE) bit);
|
|
if (index == NULL) return(NULL);
|
|
cuddRef(index);
|
|
|
|
do {
|
|
dd->reordered = 0;
|
|
res = addDoIthBit(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_addIthBit */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of internal functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of static functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
|
|
/**
|
|
@brief Performs the recursive step for Cudd_addIthBit.
|
|
|
|
@return a pointer to the %BDD if successful; NULL otherwise.
|
|
|
|
@sideeffect None
|
|
|
|
*/
|
|
static DdNode *
|
|
addDoIthBit(
|
|
DdManager * dd,
|
|
DdNode * f,
|
|
DdNode * index)
|
|
{
|
|
DdNode *res, *T, *E;
|
|
DdNode *fv, *fvn;
|
|
unsigned int mask, value;
|
|
DdHalfWord v;
|
|
|
|
statLine(dd);
|
|
/* Check terminal case. */
|
|
if (cuddIsConstant(f)) {
|
|
mask = 1U << ((unsigned int) cuddV(index));
|
|
value = (unsigned) (int) cuddV(f);
|
|
return((value & mask) == 0 ? DD_ZERO(dd) : DD_ONE(dd));
|
|
}
|
|
|
|
/* Check cache. */
|
|
res = cuddCacheLookup2(dd,addDoIthBit,f,index);
|
|
if (res != NULL) return(res);
|
|
|
|
checkWhetherToGiveUp(dd);
|
|
|
|
/* Recursive step. */
|
|
v = f->index;
|
|
fv = cuddT(f); fvn = cuddE(f);
|
|
|
|
T = addDoIthBit(dd,fv,index);
|
|
if (T == NULL) return(NULL);
|
|
cuddRef(T);
|
|
|
|
E = addDoIthBit(dd,fvn,index);
|
|
if (E == NULL) {
|
|
Cudd_RecursiveDeref(dd, T);
|
|
return(NULL);
|
|
}
|
|
cuddRef(E);
|
|
|
|
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,addDoIthBit,f,index,res);
|
|
|
|
return(res);
|
|
|
|
} /* end of addDoIthBit */
|
|
|