add isl_pw_qpolynomial_min

diff --git a/include/isl_polynomial.h b/include/isl_polynomial.h
index b2eb52e..a65ace9 100644 (file)
--- a/include/isl_polynomial.h
+++ b/include/isl_polynomial.h
@@ -124,6 +124,8 @@ __isl_give isl_qpolynomial *isl_pw_qpolynomial_eval(
 
 __isl_give isl_qpolynomial *isl_pw_qpolynomial_max(
        __isl_take isl_pw_qpolynomial *pwqp);
+__isl_give isl_qpolynomial *isl_pw_qpolynomial_min(
+       __isl_take isl_pw_qpolynomial *pwqp);
 
 int isl_pw_qpolynomial_foreach_piece(__isl_keep isl_pw_qpolynomial *pwqp,
        int (*fn)(__isl_take isl_set *set, __isl_take isl_qpolynomial *qp,

diff --git a/isl_polynomial.c b/isl_polynomial.c
index d393836..a12dc99 100644 (file)
--- a/isl_polynomial.c
+++ b/isl_polynomial.c
@@ -2630,32 +2630,35 @@ error:
        return NULL;
 }
 
-struct isl_max_data {
+struct isl_opt_data {
        isl_qpolynomial *qp;
        int first;
-       isl_qpolynomial *max;
+       isl_qpolynomial *opt;
+       int max;
 };
 
-static int max_fn(__isl_take isl_point *pnt, void *user)
+static int opt_fn(__isl_take isl_point *pnt, void *user)
 {
-       struct isl_max_data *data = (struct isl_max_data *)user;
+       struct isl_opt_data *data = (struct isl_opt_data *)user;
        isl_qpolynomial *val;
 
        val = isl_qpolynomial_eval(isl_qpolynomial_copy(data->qp), pnt);
        if (data->first) {
                data->first = 0;
-               data->max = val;
+               data->opt = val;
+       } else if (data->max) {
+               data->opt = isl_qpolynomial_max_cst(data->opt, val);
        } else {
-               data->max = isl_qpolynomial_max_cst(data->max, val);
+               data->opt = isl_qpolynomial_min_cst(data->opt, val);
        }
 
        return 0;
 }
 
-static __isl_give isl_qpolynomial *guarded_qpolynomial_max(
-       __isl_take isl_set *set, __isl_take isl_qpolynomial *qp)
+static __isl_give isl_qpolynomial *guarded_qpolynomial_opt(
+       __isl_take isl_set *set, __isl_take isl_qpolynomial *qp, int max)
 {
-       struct isl_max_data data = { NULL, 1, NULL };
+       struct isl_opt_data data = { NULL, 1, NULL, max };
 
        if (!set || !qp)
                goto error;
@@ -2668,16 +2671,16 @@ static __isl_give isl_qpolynomial *guarded_qpolynomial_max(
        set = fix_inactive(set, qp);
 
        data.qp = qp;
-       if (isl_set_foreach_point(set, max_fn, &data) < 0)
+       if (isl_set_foreach_point(set, opt_fn, &data) < 0)
                goto error;
 
        isl_set_free(set);
        isl_qpolynomial_free(qp);
-       return data.max;
+       return data.opt;
 error:
        isl_set_free(set);
        isl_qpolynomial_free(qp);
-       isl_qpolynomial_free(data.max);
+       isl_qpolynomial_free(data.opt);
        return NULL;
 }
 
@@ -2686,11 +2689,11 @@ error:
  * In the worst case, the domain is scanned completely,
  * so the domain is assumed to be bounded.
  */
-__isl_give isl_qpolynomial *isl_pw_qpolynomial_max(
-       __isl_take isl_pw_qpolynomial *pwqp)
+__isl_give isl_qpolynomial *isl_pw_qpolynomial_opt(
+       __isl_take isl_pw_qpolynomial *pwqp, int max)
 {
        int i;
-       isl_qpolynomial *max;
+       isl_qpolynomial *opt;
 
        if (!pwqp)
                return NULL;
@@ -2701,15 +2704,30 @@ __isl_give isl_qpolynomial *isl_pw_qpolynomial_max(
                return isl_qpolynomial_zero(dim);
        }
 
-       max = guarded_qpolynomial_max(isl_set_copy(pwqp->p[0].set),
-                                       isl_qpolynomial_copy(pwqp->p[0].qp));
+       opt = guarded_qpolynomial_opt(isl_set_copy(pwqp->p[0].set),
+                                       isl_qpolynomial_copy(pwqp->p[0].qp), max);
        for (i = 1; i < pwqp->n; ++i) {
-               isl_qpolynomial *max_i;
-               max_i = guarded_qpolynomial_max(isl_set_copy(pwqp->p[i].set),
-                                           isl_qpolynomial_copy(pwqp->p[i].qp));
-               max = isl_qpolynomial_max_cst(max, max_i);
+               isl_qpolynomial *opt_i;
+               opt_i = guarded_qpolynomial_opt(isl_set_copy(pwqp->p[i].set),
+                                       isl_qpolynomial_copy(pwqp->p[i].qp), max);
+               if (max)
+                       opt = isl_qpolynomial_max_cst(opt, opt_i);
+               else
+                       opt = isl_qpolynomial_min_cst(opt, opt_i);
        }
 
        isl_pw_qpolynomial_free(pwqp);
-       return max;
+       return opt;
+}
+
+__isl_give isl_qpolynomial *isl_pw_qpolynomial_max(
+       __isl_take isl_pw_qpolynomial *pwqp)
+{
+       return isl_pw_qpolynomial_opt(pwqp, 1);
+}
+
+__isl_give isl_qpolynomial *isl_pw_qpolynomial_min(
+       __isl_take isl_pw_qpolynomial *pwqp)
+{
+       return isl_pw_qpolynomial_opt(pwqp, 0);
 }