add isl_aff_mod_val

[platform/upstream/isl.git] / isl_morph.c

diff --git a/isl_morph.c b/isl_morph.c
index bd5733d..3700874 100644 (file)
--- a/isl_morph.c
+++ b/isl_morph.c
@@ -1,7 +1,7 @@
 /*
  * Copyright 2010      INRIA Saclay
  *
- * Use of this software is governed by the GNU LGPLv2.1 license
+ * Use of this software is governed by the MIT license
  *
  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
@@ -473,25 +473,26 @@ error:
  * We basically just call isl_mat_parameter_compression with the right input
  * and then extend the resulting matrix to include the variables.
  *
- * Let the equalities be given as
+ * The implementation assumes that "bset" does not have any equalities
+ * that only involve the parameters and that isl_basic_set_gauss has
+ * been applied to "bset".
  *
- *     B(p) + A x = 0
+ * Let the equalities be given as
  *
- * and let [H 0] be the Hermite Normal Form of A, then
+ *     B(p) + A x = 0.
  *
- *     H^-1 B(p)
+ * We use isl_mat_parameter_compression_ext to compute the compression
  *
- * needs to be integer, so we impose that each row is divisible by
- * the denominator.
+ *     p = T p'.
  */
 __isl_give isl_morph *isl_basic_set_parameter_compression(
        __isl_keep isl_basic_set *bset)
 {
        unsigned nparam;
        unsigned nvar;
+       unsigned n_div;
        int n_eq;
        isl_mat *H, *B;
-       isl_vec *d;
        isl_mat *map, *inv;
        isl_basic_set *dom, *ran;
 
@@ -503,28 +504,24 @@ __isl_give isl_morph *isl_basic_set_parameter_compression(
        if (bset->n_eq == 0)
                return isl_morph_identity(bset);
 
-       isl_assert(bset->ctx, bset->n_div == 0, return NULL);
-
        n_eq = bset->n_eq;
        nparam = isl_basic_set_dim(bset, isl_dim_param);
        nvar = isl_basic_set_dim(bset, isl_dim_set);
+       n_div = isl_basic_set_dim(bset, isl_dim_div);
 
-       isl_assert(bset->ctx, n_eq <= nvar, return NULL);
+       if (isl_seq_first_non_zero(bset->eq[bset->n_eq - 1] + 1 + nparam,
+                                   nvar + n_div) == -1)
+               isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
+                       "input not allowed to have parameter equalities",
+                       return NULL);
+       if (n_eq > nvar + n_div)
+               isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
+                       "input not gaussed", return NULL);
 
-       d = isl_vec_alloc(bset->ctx, n_eq);
        B = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, n_eq, 0, 1 + nparam);
-       H = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, n_eq, 1 + nparam, nvar);
-       H = isl_mat_left_hermite(H, 0, NULL, NULL);
-       H = isl_mat_drop_cols(H, n_eq, nvar - n_eq);
-       H = isl_mat_lin_to_aff(H);
-       H = isl_mat_right_inverse(H);
-       if (!H || !d)
-               goto error;
-       isl_seq_set(d->el, H->row[0][0], d->size);
-       H = isl_mat_drop_rows(H, 0, 1);
-       H = isl_mat_drop_cols(H, 0, 1);
-       B = isl_mat_product(H, B);
-       inv = isl_mat_parameter_compression(B, d);
+       H = isl_mat_sub_alloc6(bset->ctx, bset->eq,
+                               0, n_eq, 1 + nparam, nvar + n_div);
+       inv = isl_mat_parameter_compression_ext(B, H);
        inv = isl_mat_diagonal(inv, isl_mat_identity(bset->ctx, nvar));
        map = isl_mat_right_inverse(isl_mat_copy(inv));
 
@@ -532,11 +529,6 @@ __isl_give isl_morph *isl_basic_set_parameter_compression(
        ran = isl_basic_set_universe(isl_space_copy(bset->dim));
 
        return isl_morph_alloc(dom, ran, map, inv);
-error:
-       isl_mat_free(H);
-       isl_mat_free(B);
-       isl_vec_free(d);
-       return NULL;
 }
 
 /* Add stride constraints to "bset" based on the inverse mapping
@@ -562,6 +554,7 @@ error:
  *
  *     exists alpha in Z^m: B x = d alpha
  *
+ * This function is similar to add_strides in isl_affine_hull.c
  */
 static __isl_give isl_basic_set *add_strides(__isl_take isl_basic_set *bset,
        __isl_keep isl_morph *morph)
@@ -581,6 +574,7 @@ static __isl_give isl_basic_set *add_strides(__isl_take isl_basic_set *bset,
                div = isl_basic_set_alloc_div(bset);
                if (div < 0)
                        goto error;
+               isl_int_set_si(bset->div[div][0], 0);
                k = isl_basic_set_alloc_equality(bset);
                if (k < 0)
                        goto error;