/**
@brief Implements the recursive step of Cudd_addNegate.
@return a pointer to the result.
@sideeffect None
*/
DdNode *
cuddAddNegateRecur(
DdManager * dd,
DdNode * f)
{
DdNode *res,
*fv, *fvn,
*T, *E;
statLine(dd);
/* Check terminal cases. */
if (cuddIsConstant(f)) {
res = cuddUniqueConst(dd,-cuddV(f));
return(res);
}
/* Check cache */
res = cuddCacheLookup1(dd,Cudd_addNegate,f);
if (res != NULL) return(res);
checkWhetherToGiveUp(dd);
/* Recursive Step */
fv = cuddT(f);
fvn = cuddE(f);
T = cuddAddNegateRecur(dd,fv);
if (T == NULL) return(NULL);
cuddRef(T);
E = cuddAddNegateRecur(dd,fvn);
if (E == NULL) {
Cudd_RecursiveDeref(dd,T);
return(NULL);
}
cuddRef(E);
res = (T == E) ? T : cuddUniqueInter(dd,(int)f->index,T,E);
if (res == NULL) {
Cudd_RecursiveDeref(dd, T);
Cudd_RecursiveDeref(dd, E);
return(NULL);
}
cuddDeref(T);
cuddDeref(E);
/* Store result. */
cuddCacheInsert1(dd,Cudd_addNegate,f,res);
return(res);
} /* end of cuddAddNegateRecur */
/**Function********************************************************************
Synopsis [Computes the additive inverse of an ADD.]
Description [Computes the additive inverse of an ADD. Returns a pointer
to the result if successful; NULL otherwise.]
SideEffects [None]
SeeAlso [Cudd_addCmpl]
******************************************************************************/
DdNode *
Cudd_addNegate(
DdManager * dd,
DdNode * f)
{
DdNode *res;
do {
res = cuddAddNegateRecur(dd,f);
} while (dd->reordered == 1);
return(res);
} /* end of Cudd_addNegate */
/**
@brief Computes the additive inverse of an %ADD.
@return a pointer to the result if successful; NULL otherwise.
@sideeffect None
@see Cudd_addCmpl
*/
DdNode *
Cudd_addNegate(
DdManager * dd,
DdNode * f)
{
DdNode *res;
do {
dd->reordered = 0;
res = cuddAddNegateRecur(dd,f);
} while (dd->reordered == 1);
if (dd->errorCode == CUDD_TIMEOUT_EXPIRED && dd->timeoutHandler) {
dd->timeoutHandler(dd, dd->tohArg);
}
return(res);
} /* end of Cudd_addNegate */
/**Function********************************************************************
Synopsis [Integer and floating point subtraction.]
Description [Integer and floating point subtraction. Returns NULL if
not a terminal case; f - g otherwise.]
SideEffects [None]
SeeAlso [Cudd_addApply]
******************************************************************************/
DdNode *
Cudd_addMinus(
DdManager * dd,
DdNode ** f,
DdNode ** g)
{
DdNode *res;
DdNode *F, *G;
CUDD_VALUE_TYPE value;
F = *f; G = *g;
if (F == DD_ZERO(dd)) return(cuddAddNegateRecur(dd,G));
if (G == DD_ZERO(dd)) return(F);
if (cuddIsConstant(F) && cuddIsConstant(G)) {
value = cuddV(F)-cuddV(G);
res = cuddUniqueConst(dd,value);
return(res);
}
return(NULL);
} /* end of Cudd_addMinus */
