value_bounds.c

   1 /*
   2  * Copyright 2011      Leiden University. All rights reserved.
   3  * Copyright 2012-2014 Ecole Normale Superieure. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  *    1. Redistributions of source code must retain the above copyright
  10  *       notice, this list of conditions and the following disclaimer.
  11  *
  12  *    2. Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials provided
  15  *       with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY LEIDEN UNIVERSITY ''AS IS'' AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  20  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL LEIDEN UNIVERSITY OR
  21  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
  24  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * The views and conclusions contained in the software and documentation
  30  * are those of the authors and should not be interpreted as
  31  * representing official policies, either expressed or implied, of
  32  * Leiden University.
  33  */
  34
  35 #include <isl/map.h>
  36
  37 #include "expr.h"
  38 #include "value_bounds.h"
  39
  40 /* If "value_bounds" contains any bounds on the variable accessed by "arg",
  41  * then intersect the range of "map" with the valid set of values.
  42  */
  43 static __isl_give isl_map *access_apply_value_bounds(__isl_take isl_map *map,
  44         __isl_keep pet_expr *arg, __isl_keep isl_union_map *value_bounds)
  45 {
  46         isl_id *id;
  47         isl_map *vb;
  48         isl_space *space;
  49         isl_ctx *ctx = isl_map_get_ctx(map);
  50
  51         id = pet_expr_access_get_id(arg);
  52         space = isl_space_alloc(ctx, 0, 0, 1);
  53         space = isl_space_set_tuple_id(space, isl_dim_in, id);
  54         vb = isl_union_map_extract_map(value_bounds, space);
  55         if (!isl_map_plain_is_empty(vb))
  56                 map = isl_map_intersect_range(map, isl_map_range(vb));
  57         else
  58                 isl_map_free(vb);
  59
  60         return map;
  61 }
  62
  63 /* Given a set "domain", return a wrapped relation with the given set
  64  * as domain and a range of dimension "n_arg", where each coordinate
  65  * is either unbounded or, if the corresponding element of args is of
  66  * type pet_expr_access, bounded by the bounds specified by "value_bounds".
  67  */
  68 __isl_give isl_set *pet_value_bounds_apply(__isl_take isl_set *domain,
  69         unsigned n_arg, __isl_keep pet_expr **args,
  70         __isl_keep isl_union_map *value_bounds)
  71 {
  72         int i;
  73         isl_map *map;
  74         isl_space *space;
  75
  76         map = isl_map_from_domain(domain);
  77         space = isl_map_get_space(map);
  78         space = isl_space_add_dims(space, isl_dim_out, 1);
  79
  80         for (i = 0; i < n_arg; ++i) {
  81                 isl_map *map_i;
  82                 pet_expr *arg = args[i];
  83
  84                 map_i = isl_map_universe(isl_space_copy(space));
  85                 if (arg->type == pet_expr_access)
  86                         map_i = access_apply_value_bounds(map_i, arg,
  87                                                         value_bounds);
  88                 map = isl_map_flat_range_product(map, map_i);
  89         }
  90         isl_space_free(space);
  91
  92         return isl_map_wrap(map);
  93 }