Home | History | Annotate | Line # | Download | only in dist 
      1 /*
      2  * Copyright 2010      INRIA Saclay
      3  *
      4  * Use of this software is governed by the MIT license
      5  *
      6  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
      7  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
      8  * 91893 Orsay, France
      9  */
     10 
     11 /* Compute the maximal value attained by the piecewise quasipolynomial
     12  * on its domain or zero if the domain is empty.
     13  * In the worst case, the domain is scanned completely,
     14  * so the domain is assumed to be bounded.
     15  */
     16 __isl_give isl_val *FN(PW,opt)(__isl_take PW *pw, int max)
     17 {
     18 	int i;
     19 	isl_val *opt;
     20 
     21 	if (!pw)
     22 		return NULL;
     23 
     24 	if (pw->n == 0) {
     25 		opt = isl_val_zero(FN(PW,get_ctx)(pw));
     26 		FN(PW,free)(pw);
     27 		return opt;
     28 	}
     29 
     30 	opt = FN(EL,opt_on_domain)(FN(EL,copy)(pw->p[0].FIELD),
     31 					isl_set_copy(pw->p[0].set), max);
     32 	for (i = 1; i < pw->n; ++i) {
     33 		isl_val *opt_i;
     34 		opt_i = FN(EL,opt_on_domain)(FN(EL,copy)(pw->p[i].FIELD),
     35 						isl_set_copy(pw->p[i].set), max);
     36 		if (max)
     37 			opt = isl_val_max(opt, opt_i);
     38 		else
     39 			opt = isl_val_min(opt, opt_i);
     40 	}
     41 
     42 	FN(PW,free)(pw);
     43 	return opt;
     44 }
     45 
     46 __isl_give isl_val *FN(PW,max)(__isl_take PW *pw)
     47 {
     48 	return FN(PW,opt)(pw, 1);
     49 }
     50 
     51 __isl_give isl_val *FN(PW,min)(__isl_take PW *pw)
     52 {
     53 	return FN(PW,opt)(pw, 0);
     54 }
     55