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 "lhs && rhs", defined on the shared definition domain.
  49  */
  50 __isl_give isl_pw_aff *pet_and(__isl_take isl_pw_aff *lhs,
  51         __isl_take isl_pw_aff *rhs)
  52 {
  53         isl_set *cond;
  54         isl_set *dom;
  55
  56         dom = isl_set_intersect(isl_pw_aff_domain(isl_pw_aff_copy(lhs)),
  57                                  isl_pw_aff_domain(isl_pw_aff_copy(rhs)));
  58         cond = isl_set_intersect(isl_pw_aff_non_zero_set(lhs),
  59                                  isl_pw_aff_non_zero_set(rhs));
  60         return indicator_function(cond, dom);
  61 }
  62
  63 /* Return "!pa", defined on the domain of "pa".
  64  */
  65 __isl_give isl_pw_aff *pet_not(__isl_take isl_pw_aff *pa)
  66 {
  67         isl_set *cond, *dom;
  68
  69         dom = isl_pw_aff_domain(isl_pw_aff_copy(pa));
  70         cond = isl_pw_aff_zero_set(pa);
  71         pa = indicator_function(cond, dom);
  72
  73         return pa;
  74 }
  75
  76 /* Return "!!pa", i.e., a function that is equal to 1 when "pa"
  77  * is non-zero and equal to 0 when "pa" is equal to zero,
  78  * on the domain of "pa".
  79  */
  80 __isl_give isl_pw_aff *pet_to_bool(__isl_take isl_pw_aff *pa)
  81 {
  82         isl_set *cond, *dom;
  83
  84         dom = isl_pw_aff_domain(isl_pw_aff_copy(pa));
  85         cond = isl_pw_aff_non_zero_set(pa);
  86         pa = indicator_function(cond, dom);
  87
  88         return pa;
  89 }
  90
  91 /* Return the result of applying the comparison operator "type"
  92  * to "pa1" and "pa2".
  93  *
  94  * In particular, construct an isl_pw_aff that is equal to 1
  95  * on the subset of the shared domain of "pa1" and "pa2" where
  96  * the comparison holds and 0 on the other part of the shared domain.
  97  */
  98 __isl_give isl_pw_aff *pet_comparison(enum pet_op_type type,
  99         __isl_take isl_pw_aff *pa1, __isl_take isl_pw_aff *pa2)
 100 {
 101         isl_set *dom;
 102         isl_set *cond;
 103         isl_pw_aff *res;
 104
 105         dom = isl_pw_aff_domain(isl_pw_aff_copy(pa1));
 106         dom = isl_set_intersect(dom, isl_pw_aff_domain(isl_pw_aff_copy(pa2)));
 107
 108         switch (type) {
 109         case pet_op_lt:
 110                 cond = isl_pw_aff_lt_set(pa1, pa2);
 111                 break;
 112         case pet_op_le:
 113                 cond = isl_pw_aff_le_set(pa1, pa2);
 114                 break;
 115         case pet_op_gt:
 116                 cond = isl_pw_aff_gt_set(pa1, pa2);
 117                 break;
 118         case pet_op_ge:
 119                 cond = isl_pw_aff_ge_set(pa1, pa2);
 120                 break;
 121         case pet_op_eq:
 122                 cond = isl_pw_aff_eq_set(pa1, pa2);
 123                 break;
 124         case pet_op_ne:
 125                 cond = isl_pw_aff_ne_set(pa1, pa2);
 126                 break;
 127         default:
 128                 isl_die(isl_pw_aff_get_ctx(pa1), isl_error_internal,
 129                         "not a comparison operator", cond = NULL);
 130                 isl_pw_aff_free(pa1);
 131                 isl_pw_aff_free(pa2);
 132         }
 133
 134         cond = isl_set_coalesce(cond);
 135         res = indicator_function(cond, dom);
 136
 137         return res;
 138 }
 139
 140 /* Return "lhs && rhs", with shortcut semantics.
 141  * That is, if lhs is false, then the result is defined even if rhs is not.
 142  * In practice, we compute lhs ? rhs : lhs.
 143  */
 144 static __isl_give isl_pw_aff *pw_aff_and_then(__isl_take isl_pw_aff *lhs,
 145         __isl_take isl_pw_aff *rhs)
 146 {
 147         return isl_pw_aff_cond(isl_pw_aff_copy(lhs), rhs, lhs);
 148 }
 149
 150 /* Return "lhs || rhs", with shortcut semantics.
 151  * That is, if lhs is true, then the result is defined even if rhs is not.
 152  * In practice, we compute lhs ? lhs : rhs.
 153  */
 154 static __isl_give isl_pw_aff *pw_aff_or_else(__isl_take isl_pw_aff *lhs,
 155         __isl_take isl_pw_aff *rhs)
 156 {
 157         return isl_pw_aff_cond(isl_pw_aff_copy(lhs), lhs, rhs);
 158 }
 159
 160 /* Return the result of applying the boolean operator "type"
 161  * to "pa1" and "pa2".
 162  */
 163 __isl_give isl_pw_aff *pet_boolean(enum pet_op_type type,
 164         __isl_take isl_pw_aff *pa1, __isl_take isl_pw_aff *pa2)
 165 {
 166         isl_ctx *ctx;
 167
 168         switch (type) {
 169         case pet_op_land:
 170                 return pw_aff_and_then(pa1, pa2);
 171         case pet_op_lor:
 172                 return pw_aff_or_else(pa1, pa2);
 173         default:
 174                 ctx = isl_pw_aff_get_ctx(pa1);
 175                 isl_pw_aff_free(pa1);
 176                 isl_pw_aff_free(pa2);
 177                 isl_die(ctx, isl_error_internal,
 178                         "not a boolean operator", return NULL);
 179         }
 180 }