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.
264 lines
8.5 KiB
264 lines
8.5 KiB
/**CFile***********************************************************************
|
|
|
|
FileName [cuddLiteral.c]
|
|
|
|
PackageName [cudd]
|
|
|
|
Synopsis [Functions for manipulation of literal sets represented by
|
|
BDDs.]
|
|
|
|
Description [External procedures included in this file:
|
|
<ul>
|
|
<li> Cudd_bddLiteralSetIntersection()
|
|
</ul>
|
|
Internal procedures included in this file:
|
|
<ul>
|
|
<li> cuddBddLiteralSetIntersectionRecur()
|
|
</ul>]
|
|
|
|
Author [Fabio Somenzi]
|
|
|
|
Copyright [Copyright (c) 1995-2012, 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.]
|
|
|
|
******************************************************************************/
|
|
|
|
#include "util.h"
|
|
#include "cuddInt.h"
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Constant declarations */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Stucture declarations */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Type declarations */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Variable declarations */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
#ifndef lint
|
|
static char rcsid[] DD_UNUSED = "$Id: cuddLiteral.c,v 1.9 2012/02/05 01:07:19 fabio Exp $";
|
|
#endif
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Macro declarations */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**AutomaticStart*************************************************************/
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Static function prototypes */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
|
|
/**AutomaticEnd***************************************************************/
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of exported functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
|
|
/**Function********************************************************************
|
|
|
|
Synopsis [Computes the intesection of two sets of literals
|
|
represented as BDDs.]
|
|
|
|
Description [Computes the intesection of two sets of literals
|
|
represented as BDDs. Each set is represented as a cube of the
|
|
literals in the set. The empty set is represented by the constant 1.
|
|
No variable can be simultaneously present in both phases in a set.
|
|
Returns a pointer to the BDD representing the intersected sets, if
|
|
successful; NULL otherwise.]
|
|
|
|
SideEffects [None]
|
|
|
|
******************************************************************************/
|
|
DdNode *
|
|
Cudd_bddLiteralSetIntersection(
|
|
DdManager * dd,
|
|
DdNode * f,
|
|
DdNode * g)
|
|
{
|
|
DdNode *res;
|
|
|
|
do {
|
|
dd->reordered = 0;
|
|
res = cuddBddLiteralSetIntersectionRecur(dd,f,g);
|
|
} while (dd->reordered == 1);
|
|
return(res);
|
|
|
|
} /* end of Cudd_bddLiteralSetIntersection */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of internal functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
|
|
/**Function********************************************************************
|
|
|
|
Synopsis [Performs the recursive step of
|
|
Cudd_bddLiteralSetIntersection.]
|
|
|
|
Description [Performs the recursive step of
|
|
Cudd_bddLiteralSetIntersection. Scans the cubes for common variables,
|
|
and checks whether they agree in phase. Returns a pointer to the
|
|
resulting cube if successful; NULL otherwise.]
|
|
|
|
SideEffects [None]
|
|
|
|
******************************************************************************/
|
|
DdNode *
|
|
cuddBddLiteralSetIntersectionRecur(
|
|
DdManager * dd,
|
|
DdNode * f,
|
|
DdNode * g)
|
|
{
|
|
DdNode *res, *tmp;
|
|
DdNode *F, *G;
|
|
DdNode *fc, *gc;
|
|
DdNode *one;
|
|
DdNode *zero;
|
|
unsigned int topf, topg, comple;
|
|
int phasef, phaseg;
|
|
|
|
statLine(dd);
|
|
if (f == g) return(f);
|
|
|
|
F = Cudd_Regular(f);
|
|
G = Cudd_Regular(g);
|
|
one = DD_ONE(dd);
|
|
|
|
/* Here f != g. If F == G, then f and g are complementary.
|
|
** Since they are two cubes, this case only occurs when f == v,
|
|
** g == v', and v is a variable or its complement.
|
|
*/
|
|
if (F == G) return(one);
|
|
|
|
zero = Cudd_Not(one);
|
|
topf = cuddI(dd,F->index);
|
|
topg = cuddI(dd,G->index);
|
|
/* Look for a variable common to both cubes. If there are none, this
|
|
** loop will stop when the constant node is reached in both cubes.
|
|
*/
|
|
while (topf != topg) {
|
|
if (topf < topg) { /* move down on f */
|
|
comple = f != F;
|
|
f = cuddT(F);
|
|
if (comple) f = Cudd_Not(f);
|
|
if (f == zero) {
|
|
f = cuddE(F);
|
|
if (comple) f = Cudd_Not(f);
|
|
}
|
|
F = Cudd_Regular(f);
|
|
topf = cuddI(dd,F->index);
|
|
} else if (topg < topf) {
|
|
comple = g != G;
|
|
g = cuddT(G);
|
|
if (comple) g = Cudd_Not(g);
|
|
if (g == zero) {
|
|
g = cuddE(G);
|
|
if (comple) g = Cudd_Not(g);
|
|
}
|
|
G = Cudd_Regular(g);
|
|
topg = cuddI(dd,G->index);
|
|
}
|
|
}
|
|
|
|
/* At this point, f == one <=> g == 1. It suffices to test one of them. */
|
|
if (f == one) return(one);
|
|
|
|
res = cuddCacheLookup2(dd,Cudd_bddLiteralSetIntersection,f,g);
|
|
if (res != NULL) {
|
|
return(res);
|
|
}
|
|
|
|
/* Here f and g are both non constant and have the same top variable. */
|
|
comple = f != F;
|
|
fc = cuddT(F);
|
|
phasef = 1;
|
|
if (comple) fc = Cudd_Not(fc);
|
|
if (fc == zero) {
|
|
fc = cuddE(F);
|
|
phasef = 0;
|
|
if (comple) fc = Cudd_Not(fc);
|
|
}
|
|
comple = g != G;
|
|
gc = cuddT(G);
|
|
phaseg = 1;
|
|
if (comple) gc = Cudd_Not(gc);
|
|
if (gc == zero) {
|
|
gc = cuddE(G);
|
|
phaseg = 0;
|
|
if (comple) gc = Cudd_Not(gc);
|
|
}
|
|
|
|
tmp = cuddBddLiteralSetIntersectionRecur(dd,fc,gc);
|
|
if (tmp == NULL) {
|
|
return(NULL);
|
|
}
|
|
|
|
if (phasef != phaseg) {
|
|
res = tmp;
|
|
} else {
|
|
cuddRef(tmp);
|
|
if (phasef == 0) {
|
|
res = cuddBddAndRecur(dd,Cudd_Not(dd->vars[F->index]),tmp);
|
|
} else {
|
|
res = cuddBddAndRecur(dd,dd->vars[F->index],tmp);
|
|
}
|
|
if (res == NULL) {
|
|
Cudd_RecursiveDeref(dd,tmp);
|
|
return(NULL);
|
|
}
|
|
cuddDeref(tmp); /* Just cuddDeref, because it is included in result */
|
|
}
|
|
|
|
cuddCacheInsert2(dd,Cudd_bddLiteralSetIntersection,f,g,res);
|
|
|
|
return(res);
|
|
|
|
} /* end of cuddBddLiteralSetIntersectionRecur */
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Definition of static functions */
|
|
/*---------------------------------------------------------------------------*/
|
|
|