add isl_set_substitute

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>

diff --git a/isl_map.c b/isl_map.c
index b9212c8..602b2c0 100644 (file)
--- a/isl_map.c
+++ b/isl_map.c
@@ -9769,3 +9769,122 @@ __isl_give isl_aff *isl_basic_set_get_div(__isl_keep isl_basic_set *bset,
 {
        return isl_basic_map_get_div(bset, pos);
 }
+
+/* Plug in "subs" for dimension "type", "pos" of "bset".
+ *
+ * Let i be the dimension to replace and let "subs" be of the form
+ *
+ *     f/d
+ *
+ * Any integer division with a non-zero coefficient for i,
+ *
+ *     floor((a i + g)/m)
+ *
+ * is replaced by
+ *
+ *     floor((a f + d g)/(m d))
+ *
+ * Constraints of the form
+ *
+ *     a i + g
+ *
+ * are replaced by
+ *
+ *     a f + d g
+ */
+__isl_give isl_basic_set *isl_basic_set_substitute(
+       __isl_take isl_basic_set *bset,
+       enum isl_dim_type type, unsigned pos, __isl_keep isl_aff *subs)
+{
+       int i;
+       isl_int v;
+       isl_ctx *ctx;
+
+       if (bset && isl_basic_set_plain_is_empty(bset))
+               return bset;
+
+       bset = isl_basic_set_cow(bset);
+       if (!bset || !subs)
+               goto error;
+
+       ctx = isl_basic_set_get_ctx(bset);
+       if (!isl_space_is_equal(bset->dim, subs->ls->dim))
+               isl_die(ctx, isl_error_invalid,
+                       "spaces don't match", goto error);
+       if (isl_local_space_dim(subs->ls, isl_dim_div) != 0)
+               isl_die(ctx, isl_error_unsupported,
+                       "cannot handle divs yet", goto error);
+
+       pos += isl_basic_set_offset(bset, type);
+
+       isl_int_init(v);
+
+       for (i = 0; i < bset->n_eq; ++i) {
+               if (isl_int_is_zero(bset->eq[i][pos]))
+                       continue;
+               isl_int_set(v, bset->eq[i][pos]);
+               isl_int_set_si(bset->eq[i][pos], 0);
+               isl_seq_combine(bset->eq[i], subs->v->el[0], bset->eq[i],
+                               v, subs->v->el + 1, subs->v->size - 1);
+       }
+
+       for (i = 0; i < bset->n_ineq; ++i) {
+               if (isl_int_is_zero(bset->ineq[i][pos]))
+                       continue;
+               isl_int_set(v, bset->ineq[i][pos]);
+               isl_int_set_si(bset->ineq[i][pos], 0);
+               isl_seq_combine(bset->ineq[i], subs->v->el[0], bset->ineq[i],
+                               v, subs->v->el + 1, subs->v->size - 1);
+       }
+
+       for (i = 0; i < bset->n_div; ++i) {
+               if (isl_int_is_zero(bset->div[i][1 + pos]))
+                       continue;
+               isl_int_set(v, bset->div[i][1 + pos]);
+               isl_int_set_si(bset->div[i][1 + pos], 0);
+               isl_seq_combine(bset->div[i] + 1,
+                               subs->v->el[0], bset->div[i] + 1,
+                               v, subs->v->el + 1, subs->v->size - 1);
+               isl_int_mul(bset->div[i][0], bset->div[i][0], subs->v->el[0]);
+       }
+
+       isl_int_clear(v);
+
+       bset = isl_basic_set_simplify(bset);
+       return isl_basic_set_finalize(bset);
+error:
+       isl_basic_set_free(bset);
+       return NULL;
+}
+
+/* Plug in "subs" for dimension "type", "pos" of "set".
+ */
+__isl_give isl_set *isl_set_substitute(__isl_take isl_set *set,
+       enum isl_dim_type type, unsigned pos, __isl_keep isl_aff *subs)
+{
+       int i;
+
+       if (set && isl_set_plain_is_empty(set))
+               return set;
+
+       set = isl_set_cow(set);
+       if (!set || !subs)
+               goto error;
+
+       for (i = set->n - 1; i >= 0; --i) {
+               set->p[i] = isl_basic_set_substitute(set->p[i], type, pos, subs);
+               if (!set->p[i])
+                       goto error;
+               if (isl_basic_set_plain_is_empty(set->p[i])) {
+                       isl_basic_set_free(set->p[i]);
+                       if (i != set->n - 1)
+                               set->p[i] = set->p[set->n - 1];
+                       set->n--;
+               }
+       }
+
+       return set;
+error:
+       isl_set_free(set);
+       return NULL;
+}

diff --git a/isl_map_private.h b/isl_map_private.h
index 121e5cd..f3202c0 100644 (file)
--- a/isl_map_private.h
+++ b/isl_map_private.h
@@ -327,4 +327,7 @@ int isl_basic_set_foreach_lexopt(__isl_keep isl_basic_set *bset, int max,
                  void *user),
        void *user);
 
+__isl_give isl_set *isl_set_substitute(__isl_take isl_set *set,
+       enum isl_dim_type type, unsigned pos, __isl_keep isl_aff *subs);
+
 #endif