aff.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 "aff.h"
  36
  37 /* Return the piecewise affine expression "set ? 1 : 0" defined on "dom".
  38  */
  39 static __isl_give isl_pw_aff *indicator_function(__isl_take isl_set *set,
  40         __isl_take isl_set *dom)
  41 {
  42         isl_pw_aff *pa;
  43         pa = isl_set_indicator_function(set);
  44         pa = isl_pw_aff_intersect_domain(pa, isl_set_coalesce(dom));
  45         return pa;
  46 }
  47
  48 /* Return the result of applying the comparison operator "type"
  49  * to "pa1" and "pa2".
  50  *
  51  * In particular, construct an isl_pw_aff that is equal to 1
  52  * on the subset of the shared domain of "pa1" and "pa2" where
  53  * the comparison holds and 0 on the other part of the shared domain.
  54  */
  55 __isl_give isl_pw_aff *pet_comparison(enum pet_op_type type,
  56         __isl_take isl_pw_aff *pa1, __isl_take isl_pw_aff *pa2)
  57 {
  58         isl_set *dom;
  59         isl_set *cond;
  60         isl_pw_aff *res;
  61
  62         dom = isl_pw_aff_domain(isl_pw_aff_copy(pa1));
  63         dom = isl_set_intersect(dom, isl_pw_aff_domain(isl_pw_aff_copy(pa2)));
  64
  65         switch (type) {
  66         case pet_op_lt:
  67                 cond = isl_pw_aff_lt_set(pa1, pa2);
  68                 break;
  69         case pet_op_le:
  70                 cond = isl_pw_aff_le_set(pa1, pa2);
  71                 break;
  72         case pet_op_gt:
  73                 cond = isl_pw_aff_gt_set(pa1, pa2);
  74                 break;
  75         case pet_op_ge:
  76                 cond = isl_pw_aff_ge_set(pa1, pa2);
  77                 break;
  78         case pet_op_eq:
  79                 cond = isl_pw_aff_eq_set(pa1, pa2);
  80                 break;
  81         case pet_op_ne:
  82                 cond = isl_pw_aff_ne_set(pa1, pa2);
  83                 break;
  84         default:
  85                 isl_die(isl_pw_aff_get_ctx(pa1), isl_error_internal,
  86                         "not a comparison operator", cond = NULL);
  87                 isl_pw_aff_free(pa1);
  88                 isl_pw_aff_free(pa2);
  89         }
  90
  91         cond = isl_set_coalesce(cond);
  92         res = indicator_function(cond, dom);
  93
  94         return res;
  95 }