isl_bound.c

   1 /*
   2  * Copyright 2010      INRIA Saclay
   3  *
   4  * Use of this software is governed by the MIT license
   5  *
   6  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
   7  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
   8  * 91893 Orsay, France
   9  */
  10
  11 #include <isl_ctx_private.h>
  12 #include <isl_map_private.h>
  13 #include <isl_bound.h>
  14 #include <isl_bernstein.h>
  15 #include <isl_range.h>
  16 #include <isl_polynomial_private.h>
  17 #include <isl_options_private.h>
  18
  19 /* Compute a bound on the polynomial defined over the parametric polytope
  20  * using either range propagation or bernstein expansion and
  21  * store the result in bound->pwf and bound->pwf_tight.
  22  * Since bernstein expansion requires bounded domains, we apply
  23  * range propagation on unbounded domains.  Otherwise, we respect the choice
  24  * of the user.
  25  */
  26 static isl_stat compressed_guarded_poly_bound(__isl_take isl_basic_set *bset,
  27         __isl_take isl_qpolynomial *poly, void *user)
  28 {
  29         struct isl_bound *bound = (struct isl_bound *)user;
  30         int bounded;
  31
  32         if (!bset || !poly)
  33                 goto error;
  34
  35         if (bset->ctx->opt->bound == ISL_BOUND_RANGE)
  36                 return isl_qpolynomial_bound_on_domain_range(bset, poly, bound);
  37
  38         bounded = isl_basic_set_is_bounded(bset);
  39         if (bounded < 0)
  40                 goto error;
  41         if (bounded)
  42                 return isl_qpolynomial_bound_on_domain_bernstein(bset, poly, bound);
  43         else
  44                 return isl_qpolynomial_bound_on_domain_range(bset, poly, bound);
  45 error:
  46         isl_basic_set_free(bset);
  47         isl_qpolynomial_free(poly);
  48         return isl_stat_error;
  49 }
  50
  51 static isl_stat unwrapped_guarded_poly_bound(__isl_take isl_basic_set *bset,
  52         __isl_take isl_qpolynomial *poly, void *user)
  53 {
  54         struct isl_bound *bound = (struct isl_bound *)user;
  55         isl_pw_qpolynomial_fold *top_pwf;
  56         isl_pw_qpolynomial_fold *top_pwf_tight;
  57         isl_space *dim;
  58         isl_morph *morph;
  59         isl_stat r;
  60
  61         bset = isl_basic_set_detect_equalities(bset);
  62
  63         if (!bset)
  64                 goto error;
  65
  66         if (bset->n_eq == 0)
  67                 return compressed_guarded_poly_bound(bset, poly, user);
  68
  69         morph = isl_basic_set_full_compression(bset);
  70
  71         bset = isl_morph_basic_set(isl_morph_copy(morph), bset);
  72         poly = isl_qpolynomial_morph_domain(poly, isl_morph_copy(morph));
  73
  74         dim = isl_morph_get_ran_space(morph);
  75         dim = isl_space_params(dim);
  76
  77         top_pwf = bound->pwf;
  78         top_pwf_tight = bound->pwf_tight;
  79
  80         dim = isl_space_from_domain(dim);
  81         dim = isl_space_add_dims(dim, isl_dim_out, 1);
  82         bound->pwf = isl_pw_qpolynomial_fold_zero(isl_space_copy(dim),
  83                                                   bound->type);
  84         bound->pwf_tight = isl_pw_qpolynomial_fold_zero(dim, bound->type);
  85
  86         r = compressed_guarded_poly_bound(bset, poly, user);
  87
  88         morph = isl_morph_dom_params(morph);
  89         morph = isl_morph_ran_params(morph);
  90         morph = isl_morph_inverse(morph);
  91
  92         bound->pwf = isl_pw_qpolynomial_fold_morph_domain(bound->pwf,
  93                                                         isl_morph_copy(morph));
  94         bound->pwf_tight = isl_pw_qpolynomial_fold_morph_domain(
  95                                                 bound->pwf_tight, morph);
  96
  97         bound->pwf = isl_pw_qpolynomial_fold_fold(top_pwf, bound->pwf);
  98         bound->pwf_tight = isl_pw_qpolynomial_fold_fold(top_pwf_tight,
  99                                                         bound->pwf_tight);
 100
 101         return r;
 102 error:
 103         isl_basic_set_free(bset);
 104         isl_qpolynomial_free(poly);
 105         return isl_stat_error;
 106 }
 107
 108 static isl_stat guarded_poly_bound(__isl_take isl_basic_set *bset,
 109         __isl_take isl_qpolynomial *poly, void *user)
 110 {
 111         struct isl_bound *bound = (struct isl_bound *)user;
 112         isl_space *space;
 113         isl_pw_qpolynomial_fold *top_pwf;
 114         isl_pw_qpolynomial_fold *top_pwf_tight;
 115         isl_size nparam;
 116         isl_size n_in;
 117         isl_stat r;
 118
 119         if (!bound->wrapping)
 120                 return unwrapped_guarded_poly_bound(bset, poly, user);
 121
 122         nparam = isl_space_dim(bound->dim, isl_dim_param);
 123         n_in = isl_space_dim(bound->dim, isl_dim_in);
 124         if (nparam < 0 || n_in < 0)
 125                 goto error;
 126
 127         bset = isl_basic_set_move_dims(bset, isl_dim_param, nparam,
 128                                         isl_dim_set, 0, n_in);
 129         poly = isl_qpolynomial_move_dims(poly, isl_dim_param, nparam,
 130                                         isl_dim_in, 0, n_in);
 131
 132         space = isl_basic_set_get_space(bset);
 133         space = isl_space_params(space);
 134
 135         top_pwf = bound->pwf;
 136         top_pwf_tight = bound->pwf_tight;
 137
 138         space = isl_space_from_domain(space);
 139         space = isl_space_add_dims(space, isl_dim_out, 1);
 140         bound->pwf = isl_pw_qpolynomial_fold_zero(isl_space_copy(space),
 141                                                   bound->type);
 142         bound->pwf_tight = isl_pw_qpolynomial_fold_zero(space, bound->type);
 143
 144         r = unwrapped_guarded_poly_bound(bset, poly, user);
 145
 146         bound->pwf = isl_pw_qpolynomial_fold_reset_space(bound->pwf,
 147                                                     isl_space_copy(bound->dim));
 148         bound->pwf_tight = isl_pw_qpolynomial_fold_reset_space(bound->pwf_tight,
 149                                                     isl_space_copy(bound->dim));
 150
 151         bound->pwf = isl_pw_qpolynomial_fold_fold(top_pwf, bound->pwf);
 152         bound->pwf_tight = isl_pw_qpolynomial_fold_fold(top_pwf_tight,
 153                                                         bound->pwf_tight);
 154
 155         return r;
 156 error:
 157         isl_basic_set_free(bset);
 158         isl_qpolynomial_free(poly);
 159         return isl_stat_error;
 160 }
 161
 162 static isl_stat guarded_qp(__isl_take isl_qpolynomial *qp, void *user)
 163 {
 164         struct isl_bound *bound = (struct isl_bound *)user;
 165         isl_stat r;
 166
 167         r = isl_qpolynomial_as_polynomial_on_domain(qp, bound->bset,
 168                                                     &guarded_poly_bound, user);
 169         isl_qpolynomial_free(qp);
 170         return r;
 171 }
 172
 173 static isl_stat basic_guarded_fold(__isl_take isl_basic_set *bset, void *user)
 174 {
 175         struct isl_bound *bound = (struct isl_bound *)user;
 176         isl_stat r;
 177
 178         bound->bset = bset;
 179         r = isl_qpolynomial_fold_foreach_qpolynomial(bound->fold,
 180                                                         &guarded_qp, user);
 181         isl_basic_set_free(bset);
 182         return r;
 183 }
 184
 185 static isl_stat guarded_fold(__isl_take isl_set *set,
 186         __isl_take isl_qpolynomial_fold *fold, void *user)
 187 {
 188         struct isl_bound *bound = (struct isl_bound *)user;
 189
 190         if (!set || !fold)
 191                 goto error;
 192
 193         set = isl_set_make_disjoint(set);
 194
 195         bound->fold = fold;
 196         bound->type = isl_qpolynomial_fold_get_type(fold);
 197
 198         if (isl_set_foreach_basic_set(set, &basic_guarded_fold, bound) < 0)
 199                 goto error;
 200
 201         isl_set_free(set);
 202         isl_qpolynomial_fold_free(fold);
 203
 204         return isl_stat_ok;
 205 error:
 206         isl_set_free(set);
 207         isl_qpolynomial_fold_free(fold);
 208         return isl_stat_error;
 209 }
 210
 211 __isl_give isl_pw_qpolynomial_fold *isl_pw_qpolynomial_fold_bound(
 212         __isl_take isl_pw_qpolynomial_fold *pwf, isl_bool *tight)
 213 {
 214         isl_size nvar;
 215         struct isl_bound bound;
 216         isl_bool covers;
 217
 218         if (!pwf)
 219                 return NULL;
 220
 221         bound.dim = isl_pw_qpolynomial_fold_get_domain_space(pwf);
 222
 223         bound.wrapping = isl_space_is_wrapping(bound.dim);
 224         if (bound.wrapping)
 225                 bound.dim = isl_space_unwrap(bound.dim);
 226         nvar = isl_space_dim(bound.dim, isl_dim_out);
 227         if (nvar < 0)
 228                 bound.dim = isl_space_free(bound.dim);
 229         bound.dim = isl_space_domain(bound.dim);
 230         bound.dim = isl_space_from_domain(bound.dim);
 231         bound.dim = isl_space_add_dims(bound.dim, isl_dim_out, 1);
 232
 233         if (nvar == 0) {
 234                 if (tight)
 235                         *tight = isl_bool_true;
 236                 return isl_pw_qpolynomial_fold_reset_space(pwf, bound.dim);
 237         }
 238
 239         if (isl_pw_qpolynomial_fold_is_zero(pwf)) {
 240                 enum isl_fold type = pwf->type;
 241                 isl_pw_qpolynomial_fold_free(pwf);
 242                 if (tight)
 243                         *tight = isl_bool_true;
 244                 return isl_pw_qpolynomial_fold_zero(bound.dim, type);
 245         }
 246
 247         bound.pwf = isl_pw_qpolynomial_fold_zero(isl_space_copy(bound.dim),
 248                                                         pwf->type);
 249         bound.pwf_tight = isl_pw_qpolynomial_fold_zero(isl_space_copy(bound.dim),
 250                                                         pwf->type);
 251         bound.check_tight = !!tight;
 252
 253         if (isl_pw_qpolynomial_fold_foreach_lifted_piece(pwf,
 254                                                         guarded_fold, &bound) < 0)
 255                 goto error;
 256
 257         covers = isl_pw_qpolynomial_fold_covers(bound.pwf_tight, bound.pwf);
 258         if (covers < 0)
 259                 goto error;
 260
 261         if (tight)
 262                 *tight = covers;
 263
 264         isl_space_free(bound.dim);
 265         isl_pw_qpolynomial_fold_free(pwf);
 266
 267         if (covers) {
 268                 isl_pw_qpolynomial_fold_free(bound.pwf);
 269                 return bound.pwf_tight;
 270         }
 271
 272         bound.pwf = isl_pw_qpolynomial_fold_fold(bound.pwf, bound.pwf_tight);
 273
 274         return bound.pwf;
 275 error:
 276         isl_pw_qpolynomial_fold_free(bound.pwf_tight);
 277         isl_pw_qpolynomial_fold_free(bound.pwf);
 278         isl_pw_qpolynomial_fold_free(pwf);
 279         isl_space_free(bound.dim);
 280         return NULL;
 281 }
 282
 283 __isl_give isl_pw_qpolynomial_fold *isl_pw_qpolynomial_bound(
 284         __isl_take isl_pw_qpolynomial *pwqp, enum isl_fold type,
 285         isl_bool *tight)
 286 {
 287         isl_pw_qpolynomial_fold *pwf;
 288
 289         pwf = isl_pw_qpolynomial_fold_from_pw_qpolynomial(type, pwqp);
 290         return isl_pw_qpolynomial_fold_bound(pwf, tight);
 291 }
 292
 293 struct isl_union_bound_data {
 294         enum isl_fold type;
 295         isl_bool tight;
 296         isl_union_pw_qpolynomial_fold *res;
 297 };
 298
 299 static isl_stat bound_pw(__isl_take isl_pw_qpolynomial *pwqp, void *user)
 300 {
 301         struct isl_union_bound_data *data = user;
 302         isl_pw_qpolynomial_fold *pwf;
 303
 304         pwf = isl_pw_qpolynomial_bound(pwqp, data->type,
 305                                         data->tight ? &data->tight : NULL);
 306         data->res = isl_union_pw_qpolynomial_fold_fold_pw_qpolynomial_fold(
 307                                                                 data->res, pwf);
 308
 309         return isl_stat_ok;
 310 }
 311
 312 __isl_give isl_union_pw_qpolynomial_fold *isl_union_pw_qpolynomial_bound(
 313         __isl_take isl_union_pw_qpolynomial *upwqp,
 314         enum isl_fold type, isl_bool *tight)
 315 {
 316         isl_space *dim;
 317         struct isl_union_bound_data data = { type, 1, NULL };
 318
 319         if (!upwqp)
 320                 return NULL;
 321
 322         if (!tight)
 323                 data.tight = isl_bool_false;
 324
 325         dim = isl_union_pw_qpolynomial_get_space(upwqp);
 326         data.res = isl_union_pw_qpolynomial_fold_zero(dim, type);
 327         if (isl_union_pw_qpolynomial_foreach_pw_qpolynomial(upwqp,
 328                                                     &bound_pw, &data) < 0)
 329                 goto error;
 330
 331         isl_union_pw_qpolynomial_free(upwqp);
 332         if (tight)
 333                 *tight = data.tight;
 334
 335         return data.res;
 336 error:
 337         isl_union_pw_qpolynomial_free(upwqp);
 338         isl_union_pw_qpolynomial_fold_free(data.res);
 339         return NULL;
 340 }