/**Function********************************************************************
Synopsis [Integer and floating point max.]
Description [Integer and floating point max for Cudd_addApply.
Returns NULL if not a terminal case; max(f,g) otherwise.]
SideEffects [None]
SeeAlso [Cudd_addApply]
******************************************************************************/
DdNode *
Cudd_addMaximum(
DdManager * dd,
DdNode ** f,
DdNode ** g)
{
DdNode *F, *G;
F = *f; G = *g;
if (F == G) return(F);
if (F == DD_MINUS_INFINITY(dd)) return(G);
if (G == DD_MINUS_INFINITY(dd)) return(F);
#if 0
/* These special cases probably do not pay off. */
if (F == DD_PLUS_INFINITY(dd)) return(F);
if (G == DD_PLUS_INFINITY(dd)) return(G);
#endif
if (cuddIsConstant(F) && cuddIsConstant(G)) {
if (cuddV(F) >= cuddV(G)) {
return(F);
} else {
return(G);
}
}
if (F > G) { /* swap f and g */
*f = G;
*g = F;
}
return(NULL);
} /* end of Cudd_addMaximum */
/**Function********************************************************************
Synopsis [Determines whether f is less than or equal to g.]
Description [Returns 1 if f is less than or equal to g; 0 otherwise.
No new nodes are created. This procedure works for arbitrary ADDs.
For 0-1 ADDs Cudd_addEvalConst is more efficient.]
SideEffects [None]
SeeAlso [Cudd_addIteConstant Cudd_addEvalConst Cudd_bddLeq]
******************************************************************************/
int
Cudd_addLeq(
DdManager * dd,
DdNode * f,
DdNode * g)
{
DdNode *tmp, *fv, *fvn, *gv, *gvn;
unsigned int topf, topg, res;
/* Terminal cases. */
if (f == g) return(1);
statLine(dd);
if (cuddIsConstant(f)) {
if (cuddIsConstant(g)) return(cuddV(f) <= cuddV(g));
if (f == DD_MINUS_INFINITY(dd)) return(1);
if (f == DD_PLUS_INFINITY(dd)) return(0); /* since f != g */
}
if (g == DD_PLUS_INFINITY(dd)) return(1);
if (g == DD_MINUS_INFINITY(dd)) return(0); /* since f != g */
/* Check cache. */
tmp = cuddCacheLookup2(dd,(DD_CTFP)Cudd_addLeq,f,g);
if (tmp != NULL) {
return(tmp == DD_ONE(dd));
}
/* Compute cofactors. One of f and g is not constant. */
topf = cuddI(dd,f->index);
topg = cuddI(dd,g->index);
if (topf <= topg) {
fv = cuddT(f); fvn = cuddE(f);
} else {
fv = fvn = f;
}
if (topg <= topf) {
gv = cuddT(g); gvn = cuddE(g);
} else {
gv = gvn = g;
}
res = Cudd_addLeq(dd,fvn,gvn) && Cudd_addLeq(dd,fv,gv);
/* Store result in cache and return. */
cuddCacheInsert2(dd,(DD_CTFP) Cudd_addLeq,f,g,
Cudd_NotCond(DD_ONE(dd),res==0));
return(res);
} /* end of Cudd_addLeq */
/**Function********************************************************************
Synopsis [Finds the minimum discriminant of f.]
Description [Returns a pointer to a constant ADD.]
SideEffects [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);
}
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 */
