isl_map_simplify.c

   1 #include "isl_equalities.h"
   2 #include "isl_map.h"
   3 #include "isl_map_private.h"
   4
   5 static void swap_equality(struct isl_basic_map *bmap, int a, int b)
   6 {
   7         isl_int *t = bmap->eq[a];
   8         bmap->eq[a] = bmap->eq[b];
   9         bmap->eq[b] = t;
  10 }
  11
  12 static void swap_inequality(struct isl_basic_map *bmap, int a, int b)
  13 {
  14         if (a != b) {
  15                 isl_int *t = bmap->ineq[a];
  16                 bmap->ineq[a] = bmap->ineq[b];
  17                 bmap->ineq[b] = t;
  18         }
  19 }
  20
  21 static void set_swap_inequality(struct isl_basic_set *bset, int a, int b)
  22 {
  23         swap_inequality((struct isl_basic_map *)bset, a, b);
  24 }
  25
  26 static void constraint_drop_vars(isl_int *c, unsigned n, unsigned rem)
  27 {
  28         isl_seq_cpy(c, c + n, rem);
  29         isl_seq_clr(c + rem, n);
  30 }
  31
  32 /* Drop n dimensions starting at first.
  33  *
  34  * In principle, this frees up some extra variables as the number
  35  * of columns remains constant, but we would have to extend
  36  * the div array too as the number of rows in this array is assumed
  37  * to be equal to extra.
  38  */
  39 struct isl_basic_set *isl_basic_set_drop_dims(
  40                 struct isl_basic_set *bset, unsigned first, unsigned n)
  41 {
  42         int i;
  43
  44         if (!bset)
  45                 goto error;
  46
  47         isl_assert(bset->ctx, first + n <= bset->dim->n_out, goto error);
  48
  49         if (n == 0)
  50                 return bset;
  51
  52         bset = isl_basic_set_cow(bset);
  53         if (!bset)
  54                 return NULL;
  55
  56         for (i = 0; i < bset->n_eq; ++i)
  57                 constraint_drop_vars(bset->eq[i]+1+bset->dim->nparam+first, n,
  58                                      (bset->dim->n_out-first-n)+bset->extra);
  59
  60         for (i = 0; i < bset->n_ineq; ++i)
  61                 constraint_drop_vars(bset->ineq[i]+1+bset->dim->nparam+first, n,
  62                                      (bset->dim->n_out-first-n)+bset->extra);
  63
  64         for (i = 0; i < bset->n_div; ++i)
  65                 constraint_drop_vars(bset->div[i]+1+1+bset->dim->nparam+first, n,
  66                                      (bset->dim->n_out-first-n)+bset->extra);
  67
  68         bset->dim = isl_dim_drop_outputs(bset->dim, first, n);
  69         if (!bset->dim)
  70                 goto error;
  71
  72         F_CLR(bset, ISL_BASIC_SET_NORMALIZED);
  73         bset = isl_basic_set_simplify(bset);
  74         return isl_basic_set_finalize(bset);
  75 error:
  76         isl_basic_set_free(bset);
  77         return NULL;
  78 }
  79
  80 struct isl_set *isl_set_drop_dims(
  81                 struct isl_set *set, unsigned first, unsigned n)
  82 {
  83         int i;
  84
  85         if (!set)
  86                 goto error;
  87
  88         isl_assert(set->ctx, first + n <= set->dim->n_out, goto error);
  89
  90         if (n == 0)
  91                 return set;
  92         set = isl_set_cow(set);
  93         if (!set)
  94                 goto error;
  95         set->dim = isl_dim_drop_outputs(set->dim, first, n);
  96         if (!set->dim)
  97                 goto error;
  98
  99         for (i = 0; i < set->n; ++i) {
 100                 set->p[i] = isl_basic_set_drop_dims(set->p[i], first, n);
 101                 if (!set->p[i])
 102                         goto error;
 103         }
 104
 105         F_CLR(set, ISL_SET_NORMALIZED);
 106         return set;
 107 error:
 108         isl_set_free(set);
 109         return NULL;
 110 }
 111
 112 /* Drop n input dimensions starting at first.
 113  *
 114  * In principle, this frees up some extra variables as the number
 115  * of columns remains constant, but we would have to extend
 116  * the div array too as the number of rows in this array is assumed
 117  * to be equal to extra.
 118  */
 119 struct isl_basic_map *isl_basic_map_drop_inputs(
 120                 struct isl_basic_map *bmap, unsigned first, unsigned n)
 121 {
 122         int i;
 123         unsigned nparam;
 124         unsigned n_in;
 125         unsigned n_out;
 126
 127         if (!bmap)
 128                 goto error;
 129
 130         nparam = isl_basic_map_n_param(bmap);
 131         n_in = isl_basic_map_n_in(bmap);
 132         n_out = isl_basic_map_n_out(bmap);
 133         isl_assert(bmap->ctx, first + n <= n_in, goto error);
 134
 135         if (n == 0)
 136                 return bmap;
 137
 138         bmap = isl_basic_map_cow(bmap);
 139         if (!bmap)
 140                 return NULL;
 141
 142         for (i = 0; i < bmap->n_eq; ++i)
 143                 constraint_drop_vars(bmap->eq[i]+1+nparam+first, n,
 144                                  (n_in-first-n)+n_out+bmap->extra);
 145
 146         for (i = 0; i < bmap->n_ineq; ++i)
 147                 constraint_drop_vars(bmap->ineq[i]+1+nparam+first, n,
 148                                  (n_in-first-n)+n_out+bmap->extra);
 149
 150         for (i = 0; i < bmap->n_div; ++i)
 151                 constraint_drop_vars(bmap->div[i]+1+1+nparam+first, n,
 152                                  (n_in-first-n)+n_out+bmap->extra);
 153
 154         bmap->dim = isl_dim_drop_inputs(bmap->dim, first, n);
 155         if (!bmap->dim)
 156                 goto error;
 157
 158         F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 159         bmap = isl_basic_map_simplify(bmap);
 160         return isl_basic_map_finalize(bmap);
 161 error:
 162         isl_basic_map_free(bmap);
 163         return NULL;
 164 }
 165
 166 struct isl_map *isl_map_drop_inputs(
 167                 struct isl_map *map, unsigned first, unsigned n)
 168 {
 169         int i;
 170
 171         if (!map)
 172                 goto error;
 173
 174         isl_assert(map->ctx, first + n <= map->dim->n_in, goto error);
 175
 176         if (n == 0)
 177                 return map;
 178         map = isl_map_cow(map);
 179         if (!map)
 180                 goto error;
 181         map->dim = isl_dim_drop_inputs(map->dim, first, n);
 182         if (!map->dim)
 183                 goto error;
 184
 185         for (i = 0; i < map->n; ++i) {
 186                 map->p[i] = isl_basic_map_drop_inputs(map->p[i], first, n);
 187                 if (!map->p[i])
 188                         goto error;
 189         }
 190         F_CLR(map, ISL_MAP_NORMALIZED);
 191
 192         return map;
 193 error:
 194         isl_map_free(map);
 195         return NULL;
 196 }
 197
 198 /*
 199  * We don't cow, as the div is assumed to be redundant.
 200  */
 201 static struct isl_basic_map *isl_basic_map_drop_div(
 202                 struct isl_basic_map *bmap, unsigned div)
 203 {
 204         int i;
 205         unsigned pos;
 206
 207         if (!bmap)
 208                 goto error;
 209
 210         pos = 1 + isl_dim_total(bmap->dim) + div;
 211
 212         isl_assert(bmap->ctx, div < bmap->n_div, goto error);
 213
 214         for (i = 0; i < bmap->n_eq; ++i)
 215                 constraint_drop_vars(bmap->eq[i]+pos, 1, bmap->extra-div-1);
 216
 217         for (i = 0; i < bmap->n_ineq; ++i) {
 218                 if (!isl_int_is_zero(bmap->ineq[i][pos])) {
 219                         isl_basic_map_drop_inequality(bmap, i);
 220                         --i;
 221                         continue;
 222                 }
 223                 constraint_drop_vars(bmap->ineq[i]+pos, 1, bmap->extra-div-1);
 224         }
 225
 226         for (i = 0; i < bmap->n_div; ++i)
 227                 constraint_drop_vars(bmap->div[i]+1+pos, 1, bmap->extra-div-1);
 228
 229         if (div != bmap->n_div - 1) {
 230                 int j;
 231                 isl_int *t = bmap->div[div];
 232
 233                 for (j = div; j < bmap->n_div - 1; ++j)
 234                         bmap->div[j] = bmap->div[j+1];
 235
 236                 bmap->div[bmap->n_div - 1] = t;
 237         }
 238         F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 239         isl_basic_map_free_div(bmap, 1);
 240
 241         return bmap;
 242 error:
 243         isl_basic_map_free(bmap);
 244         return NULL;
 245 }
 246
 247 static struct isl_basic_map *normalize_constraints(struct isl_basic_map *bmap)
 248 {
 249         int i;
 250         isl_int gcd;
 251         unsigned total = isl_basic_map_total_dim(bmap);
 252
 253         isl_int_init(gcd);
 254         for (i = bmap->n_eq - 1; i >= 0; --i) {
 255                 isl_seq_gcd(bmap->eq[i]+1, total, &gcd);
 256                 if (isl_int_is_zero(gcd)) {
 257                         if (!isl_int_is_zero(bmap->eq[i][0])) {
 258                                 bmap = isl_basic_map_set_to_empty(bmap);
 259                                 break;
 260                         }
 261                         isl_basic_map_drop_equality(bmap, i);
 262                         continue;
 263                 }
 264                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
 265                         isl_int_gcd(gcd, gcd, bmap->eq[i][0]);
 266                 if (isl_int_is_one(gcd))
 267                         continue;
 268                 if (!isl_int_is_divisible_by(bmap->eq[i][0], gcd)) {
 269                         bmap = isl_basic_map_set_to_empty(bmap);
 270                         break;
 271                 }
 272                 isl_seq_scale_down(bmap->eq[i], bmap->eq[i], gcd, 1+total);
 273         }
 274
 275         for (i = bmap->n_ineq - 1; i >= 0; --i) {
 276                 isl_seq_gcd(bmap->ineq[i]+1, total, &gcd);
 277                 if (isl_int_is_zero(gcd)) {
 278                         if (isl_int_is_neg(bmap->ineq[i][0])) {
 279                                 bmap = isl_basic_map_set_to_empty(bmap);
 280                                 break;
 281                         }
 282                         isl_basic_map_drop_inequality(bmap, i);
 283                         continue;
 284                 }
 285                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
 286                         isl_int_gcd(gcd, gcd, bmap->ineq[i][0]);
 287                 if (isl_int_is_one(gcd))
 288                         continue;
 289                 isl_int_fdiv_q(bmap->ineq[i][0], bmap->ineq[i][0], gcd);
 290                 isl_seq_scale_down(bmap->ineq[i]+1, bmap->ineq[i]+1, gcd, total);
 291         }
 292         isl_int_clear(gcd);
 293
 294         return bmap;
 295 }
 296
 297 static void eliminate_div(struct isl_basic_map *bmap, isl_int *eq, unsigned div)
 298 {
 299         int i;
 300         unsigned pos = 1 + isl_dim_total(bmap->dim) + div;
 301         unsigned len;
 302         len = 1 + isl_basic_map_total_dim(bmap);
 303
 304         for (i = 0; i < bmap->n_eq; ++i)
 305                 if (bmap->eq[i] != eq)
 306                         isl_seq_elim(bmap->eq[i], eq, pos, len, NULL);
 307
 308         for (i = 0; i < bmap->n_ineq; ++i)
 309                 isl_seq_elim(bmap->ineq[i], eq, pos, len, NULL);
 310
 311         /* We need to be careful about circular definitions,
 312          * so for now we just remove the definitions of other divs that
 313          * depend on this div and (possibly) recompute them later.
 314          */
 315         for (i = 0; i < bmap->n_div; ++i)
 316                 if (!isl_int_is_zero(bmap->div[i][0]) &&
 317                     !isl_int_is_zero(bmap->div[i][1 + pos]))
 318                         isl_seq_clr(bmap->div[i], 1 + len);
 319
 320         isl_basic_map_drop_div(bmap, div);
 321 }
 322
 323 /* Elimininate divs based on equalities
 324  */
 325 static struct isl_basic_map *eliminate_divs_eq(
 326                 struct isl_basic_map *bmap, int *progress)
 327 {
 328         int d;
 329         int i;
 330         int modified = 0;
 331         unsigned off;
 332
 333         if (!bmap)
 334                 return NULL;
 335
 336         off = 1 + isl_dim_total(bmap->dim);
 337
 338         for (d = bmap->n_div - 1; d >= 0 ; --d) {
 339                 for (i = 0; i < bmap->n_eq; ++i) {
 340                         if (!isl_int_is_one(bmap->eq[i][off + d]) &&
 341                             !isl_int_is_negone(bmap->eq[i][off + d]))
 342                                 continue;
 343                         modified = 1;
 344                         *progress = 1;
 345                         eliminate_div(bmap, bmap->eq[i], d);
 346                         isl_basic_map_drop_equality(bmap, i);
 347                         break;
 348                 }
 349         }
 350         if (modified)
 351                 return eliminate_divs_eq(bmap, progress);
 352         return bmap;
 353 }
 354
 355 /* Elimininate divs based on inequalities
 356  */
 357 static struct isl_basic_map *eliminate_divs_ineq(
 358                 struct isl_basic_map *bmap, int *progress)
 359 {
 360         int d;
 361         int i;
 362         unsigned off;
 363         struct isl_ctx *ctx;
 364
 365         if (!bmap)
 366                 return NULL;
 367
 368         ctx = bmap->ctx;
 369         off = 1 + isl_dim_total(bmap->dim);
 370
 371         for (d = bmap->n_div - 1; d >= 0 ; --d) {
 372                 for (i = 0; i < bmap->n_eq; ++i)
 373                         if (!isl_int_is_zero(bmap->eq[i][off + d]))
 374                                 break;
 375                 if (i < bmap->n_eq)
 376                         continue;
 377                 for (i = 0; i < bmap->n_ineq; ++i)
 378                         if (isl_int_abs_gt(bmap->ineq[i][off + d], ctx->one))
 379                                 break;
 380                 if (i < bmap->n_ineq)
 381                         continue;
 382                 *progress = 1;
 383                 bmap = isl_basic_map_eliminate_vars(bmap, (off-1)+d, 1);
 384                 if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
 385                         break;
 386                 bmap = isl_basic_map_drop_div(bmap, d);
 387                 if (!bmap)
 388                         break;
 389         }
 390         return bmap;
 391 }
 392
 393 static void eliminate_var_using_equality(struct isl_basic_map *bmap,
 394         unsigned pos, isl_int *eq, int *progress)
 395 {
 396         unsigned total;
 397         int k;
 398
 399         total = isl_basic_map_total_dim(bmap);
 400         for (k = 0; k < bmap->n_eq; ++k) {
 401                 if (bmap->eq[k] == eq)
 402                         continue;
 403                 if (isl_int_is_zero(bmap->eq[k][1+pos]))
 404                         continue;
 405                 if (progress)
 406                         *progress = 1;
 407                 isl_seq_elim(bmap->eq[k], eq, 1+pos, 1+total, NULL);
 408         }
 409
 410         for (k = 0; k < bmap->n_ineq; ++k) {
 411                 if (isl_int_is_zero(bmap->ineq[k][1+pos]))
 412                         continue;
 413                 if (progress)
 414                         *progress = 1;
 415                 isl_seq_elim(bmap->ineq[k], eq, 1+pos, 1+total, NULL);
 416                 F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 417         }
 418
 419         for (k = 0; k < bmap->n_div; ++k) {
 420                 if (isl_int_is_zero(bmap->div[k][0]))
 421                         continue;
 422                 if (isl_int_is_zero(bmap->div[k][1+1+pos]))
 423                         continue;
 424                 if (progress)
 425                         *progress = 1;
 426                 isl_seq_elim(bmap->div[k]+1, eq,
 427                                 1+pos, 1+total, &bmap->div[k][0]);
 428                 F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 429         }
 430 }
 431
 432 struct isl_basic_map *isl_basic_map_gauss(
 433         struct isl_basic_map *bmap, int *progress)
 434 {
 435         int k;
 436         int done;
 437         int last_var;
 438         unsigned total_var;
 439         unsigned total;
 440
 441         if (!bmap)
 442                 return NULL;
 443
 444         total = isl_basic_map_total_dim(bmap);
 445         total_var = total - bmap->n_div;
 446
 447         last_var = total - 1;
 448         for (done = 0; done < bmap->n_eq; ++done) {
 449                 for (; last_var >= 0; --last_var) {
 450                         for (k = done; k < bmap->n_eq; ++k)
 451                                 if (!isl_int_is_zero(bmap->eq[k][1+last_var]))
 452                                         break;
 453                         if (k < bmap->n_eq)
 454                                 break;
 455                 }
 456                 if (last_var < 0)
 457                         break;
 458                 if (k != done)
 459                         swap_equality(bmap, k, done);
 460                 if (isl_int_is_neg(bmap->eq[done][1+last_var]))
 461                         isl_seq_neg(bmap->eq[done], bmap->eq[done], 1+total);
 462
 463                 eliminate_var_using_equality(bmap, last_var, bmap->eq[done],
 464                                                 progress);
 465
 466                 if (last_var >= total_var &&
 467                     isl_int_is_zero(bmap->div[last_var - total_var][0])) {
 468                         unsigned div = last_var - total_var;
 469                         isl_seq_neg(bmap->div[div]+1, bmap->eq[done], 1+total);
 470                         isl_int_set_si(bmap->div[div][1+1+last_var], 0);
 471                         isl_int_set(bmap->div[div][0],
 472                                     bmap->eq[done][1+last_var]);
 473                         F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 474                 }
 475         }
 476         if (done == bmap->n_eq)
 477                 return bmap;
 478         for (k = done; k < bmap->n_eq; ++k) {
 479                 if (isl_int_is_zero(bmap->eq[k][0]))
 480                         continue;
 481                 return isl_basic_map_set_to_empty(bmap);
 482         }
 483         isl_basic_map_free_equality(bmap, bmap->n_eq-done);
 484         return bmap;
 485 }
 486
 487 struct isl_basic_set *isl_basic_set_gauss(
 488         struct isl_basic_set *bset, int *progress)
 489 {
 490         return (struct isl_basic_set*)isl_basic_map_gauss(
 491                         (struct isl_basic_map *)bset, progress);
 492 }
 493
 494
 495 static unsigned int round_up(unsigned int v)
 496 {
 497         int old_v = v;
 498
 499         while (v) {
 500                 old_v = v;
 501                 v ^= v & -v;
 502         }
 503         return old_v << 1;
 504 }
 505
 506 static int hash_index(isl_int ***index, unsigned int size, int bits,
 507                         struct isl_basic_map *bmap, int k)
 508 {
 509         int h;
 510         unsigned total = isl_basic_map_total_dim(bmap);
 511         uint32_t hash = isl_seq_get_hash_bits(bmap->ineq[k]+1, total, bits);
 512         for (h = hash; index[h]; h = (h+1) % size)
 513                 if (&bmap->ineq[k] != index[h] &&
 514                     isl_seq_eq(bmap->ineq[k]+1, index[h][0]+1, total))
 515                         break;
 516         return h;
 517 }
 518
 519 static int set_hash_index(isl_int ***index, unsigned int size, int bits,
 520                           struct isl_basic_set *bset, int k)
 521 {
 522         return hash_index(index, size, bits, (struct isl_basic_map *)bset, k);
 523 }
 524
 525 static struct isl_basic_map *remove_duplicate_divs(
 526         struct isl_basic_map *bmap, int *progress)
 527 {
 528         unsigned int size;
 529         int *index;
 530         int k, l, h;
 531         int bits;
 532         struct isl_blk eq;
 533         unsigned total_var = isl_dim_total(bmap->dim);
 534         unsigned total = total_var + bmap->n_div;
 535         struct isl_ctx *ctx;
 536
 537         if (bmap->n_div <= 1)
 538                 return bmap;
 539
 540         ctx = bmap->ctx;
 541         for (k = bmap->n_div - 1; k >= 0; --k)
 542                 if (!isl_int_is_zero(bmap->div[k][0]))
 543                         break;
 544         if (k <= 0)
 545                 return bmap;
 546
 547         size = round_up(4 * bmap->n_div / 3 - 1);
 548         bits = ffs(size) - 1;
 549         index = isl_calloc_array(ctx, int, size);
 550         if (!index)
 551                 return bmap;
 552         eq = isl_blk_alloc(ctx, 1+total);
 553         if (isl_blk_is_error(eq))
 554                 goto out;
 555
 556         isl_seq_clr(eq.data, 1+total);
 557         index[isl_seq_get_hash_bits(bmap->div[k], 2+total, bits)] = k + 1;
 558         for (--k; k >= 0; --k) {
 559                 uint32_t hash;
 560
 561                 if (isl_int_is_zero(bmap->div[k][0]))
 562                         continue;
 563
 564                 hash = isl_seq_get_hash_bits(bmap->div[k], 2+total, bits);
 565                 for (h = hash; index[h]; h = (h+1) % size)
 566                         if (isl_seq_eq(bmap->div[k],
 567                                        bmap->div[index[h]-1], 2+total))
 568                                 break;
 569                 if (index[h]) {
 570                         *progress = 1;
 571                         l = index[h] - 1;
 572                         isl_int_set_si(eq.data[1+total_var+k], -1);
 573                         isl_int_set_si(eq.data[1+total_var+l], 1);
 574                         eliminate_div(bmap, eq.data, l);
 575                         isl_int_set_si(eq.data[1+total_var+k], 0);
 576                         isl_int_set_si(eq.data[1+total_var+l], 0);
 577                 }
 578                 index[h] = k+1;
 579         }
 580
 581         isl_blk_free(ctx, eq);
 582 out:
 583         free(index);
 584         return bmap;
 585 }
 586
 587 static struct isl_basic_map *remove_duplicate_constraints(
 588         struct isl_basic_map *bmap, int *progress)
 589 {
 590         unsigned int size;
 591         isl_int ***index;
 592         int k, l, h;
 593         int bits;
 594         unsigned total = isl_basic_map_total_dim(bmap);
 595         isl_int sum;
 596
 597         if (bmap->n_ineq <= 1)
 598                 return bmap;
 599
 600         size = round_up(4 * (bmap->n_ineq+1) / 3 - 1);
 601         bits = ffs(size) - 1;
 602         index = isl_calloc_array(ctx, isl_int **, size);
 603         if (!index)
 604                 return bmap;
 605
 606         index[isl_seq_get_hash_bits(bmap->ineq[0]+1, total, bits)] = &bmap->ineq[0];
 607         for (k = 1; k < bmap->n_ineq; ++k) {
 608                 h = hash_index(index, size, bits, bmap, k);
 609                 if (!index[h]) {
 610                         index[h] = &bmap->ineq[k];
 611                         continue;
 612                 }
 613                 if (progress)
 614                         *progress = 1;
 615                 l = index[h] - &bmap->ineq[0];
 616                 if (isl_int_lt(bmap->ineq[k][0], bmap->ineq[l][0]))
 617                         swap_inequality(bmap, k, l);
 618                 isl_basic_map_drop_inequality(bmap, k);
 619                 --k;
 620         }
 621         isl_int_init(sum);
 622         for (k = 0; k < bmap->n_ineq-1; ++k) {
 623                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 624                 h = hash_index(index, size, bits, bmap, k);
 625                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 626                 if (!index[h])
 627                         continue;
 628                 l = index[h] - &bmap->ineq[0];
 629                 isl_int_add(sum, bmap->ineq[k][0], bmap->ineq[l][0]);
 630                 if (isl_int_is_pos(sum))
 631                         continue;
 632                 if (isl_int_is_zero(sum)) {
 633                         /* We need to break out of the loop after these
 634                          * changes since the contents of the hash
 635                          * will no longer be valid.
 636                          * Plus, we probably we want to regauss first.
 637                          */
 638                         isl_basic_map_drop_inequality(bmap, l);
 639                         isl_basic_map_inequality_to_equality(bmap, k);
 640                 } else
 641                         bmap = isl_basic_map_set_to_empty(bmap);
 642                 break;
 643         }
 644         isl_int_clear(sum);
 645
 646         free(index);
 647         return bmap;
 648 }
 649
 650
 651 struct isl_basic_map *isl_basic_map_simplify(struct isl_basic_map *bmap)
 652 {
 653         int progress = 1;
 654         if (!bmap)
 655                 return NULL;
 656         while (progress) {
 657                 progress = 0;
 658                 bmap = normalize_constraints(bmap);
 659                 bmap = eliminate_divs_eq(bmap, &progress);
 660                 bmap = eliminate_divs_ineq(bmap, &progress);
 661                 bmap = isl_basic_map_gauss(bmap, &progress);
 662                 bmap = remove_duplicate_divs(bmap, &progress);
 663                 bmap = remove_duplicate_constraints(bmap, &progress);
 664         }
 665         return bmap;
 666 }
 667
 668 struct isl_basic_set *isl_basic_set_simplify(struct isl_basic_set *bset)
 669 {
 670         return (struct isl_basic_set *)
 671                 isl_basic_map_simplify((struct isl_basic_map *)bset);
 672 }
 673
 674
 675 /* If the only constraints a div d=floor(f/m)
 676  * appears in are its two defining constraints
 677  *
 678  *      f - m d >=0
 679  *      -(f - (m - 1)) + m d >= 0
 680  *
 681  * then it can safely be removed.
 682  */
 683 static int div_is_redundant(struct isl_basic_map *bmap, int div)
 684 {
 685         int i;
 686         unsigned pos = 1 + isl_dim_total(bmap->dim) + div;
 687
 688         for (i = 0; i < bmap->n_eq; ++i)
 689                 if (!isl_int_is_zero(bmap->eq[i][pos]))
 690                         return 0;
 691
 692         for (i = 0; i < bmap->n_ineq; ++i) {
 693                 if (isl_int_is_zero(bmap->ineq[i][pos]))
 694                         continue;
 695                 if (isl_int_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
 696                         int neg;
 697                         isl_int_sub(bmap->div[div][1],
 698                                         bmap->div[div][1], bmap->div[div][0]);
 699                         isl_int_add_ui(bmap->div[div][1], bmap->div[div][1], 1);
 700                         neg = isl_seq_is_neg(bmap->ineq[i], bmap->div[div]+1, pos);
 701                         isl_int_sub_ui(bmap->div[div][1], bmap->div[div][1], 1);
 702                         isl_int_add(bmap->div[div][1],
 703                                         bmap->div[div][1], bmap->div[div][0]);
 704                         if (!neg)
 705                                 return 0;
 706                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
 707                                                     bmap->n_div-div-1) != -1)
 708                                 return 0;
 709                 } else if (isl_int_abs_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
 710                         if (!isl_seq_eq(bmap->ineq[i], bmap->div[div]+1, pos))
 711                                 return 0;
 712                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
 713                                                     bmap->n_div-div-1) != -1)
 714                                 return 0;
 715                 } else
 716                         return 0;
 717         }
 718
 719         for (i = 0; i < bmap->n_div; ++i)
 720                 if (!isl_int_is_zero(bmap->div[i][1+pos]))
 721                         return 0;
 722
 723         return 1;
 724 }
 725
 726 /*
 727  * Remove divs that don't occur in any of the constraints or other divs.
 728  * These can arise when dropping some of the variables in a quast
 729  * returned by piplib.
 730  */
 731 static struct isl_basic_map *remove_redundant_divs(struct isl_basic_map *bmap)
 732 {
 733         int i;
 734
 735         if (!bmap)
 736                 return NULL;
 737
 738         for (i = bmap->n_div-1; i >= 0; --i) {
 739                 if (!div_is_redundant(bmap, i))
 740                         continue;
 741                 bmap = isl_basic_map_drop_div(bmap, i);
 742         }
 743         return bmap;
 744 }
 745
 746 struct isl_basic_map *isl_basic_map_finalize(struct isl_basic_map *bmap)
 747 {
 748         bmap = remove_redundant_divs(bmap);
 749         if (!bmap)
 750                 return NULL;
 751         F_SET(bmap, ISL_BASIC_SET_FINAL);
 752         return bmap;
 753 }
 754
 755 struct isl_basic_set *isl_basic_set_finalize(struct isl_basic_set *bset)
 756 {
 757         return (struct isl_basic_set *)
 758                 isl_basic_map_finalize((struct isl_basic_map *)bset);
 759 }
 760
 761 struct isl_set *isl_set_finalize(struct isl_set *set)
 762 {
 763         int i;
 764
 765         if (!set)
 766                 return NULL;
 767         for (i = 0; i < set->n; ++i) {
 768                 set->p[i] = isl_basic_set_finalize(set->p[i]);
 769                 if (!set->p[i])
 770                         goto error;
 771         }
 772         return set;
 773 error:
 774         isl_set_free(set);
 775         return NULL;
 776 }
 777
 778 struct isl_map *isl_map_finalize(struct isl_map *map)
 779 {
 780         int i;
 781
 782         if (!map)
 783                 return NULL;
 784         for (i = 0; i < map->n; ++i) {
 785                 map->p[i] = isl_basic_map_finalize(map->p[i]);
 786                 if (!map->p[i])
 787                         goto error;
 788         }
 789         F_CLR(map, ISL_MAP_NORMALIZED);
 790         return map;
 791 error:
 792         isl_map_free(map);
 793         return NULL;
 794 }
 795
 796
 797 /* Remove any div that is defined in terms of the given variable.
 798  */
 799 static struct isl_basic_map *remove_dependent_vars(struct isl_basic_map *bmap,
 800                                                                         int pos)
 801 {
 802         int i;
 803         unsigned dim = isl_dim_total(bmap->dim);
 804
 805         for (i = 0; i < bmap->n_div; ++i) {
 806                 if (isl_int_is_zero(bmap->div[i][0]))
 807                         continue;
 808                 if (isl_int_is_zero(bmap->div[i][1+1+pos]))
 809                         continue;
 810                 bmap = isl_basic_map_eliminate_vars(bmap, dim + i, 1);
 811                 if (!bmap)
 812                         return NULL;
 813         }
 814         return bmap;
 815 }
 816
 817 /* Eliminate the specified variables from the constraints using
 818  * Fourier-Motzkin.  The variables themselves are not removed.
 819  */
 820 struct isl_basic_map *isl_basic_map_eliminate_vars(
 821         struct isl_basic_map *bmap, unsigned pos, unsigned n)
 822 {
 823         int d;
 824         int i, j, k;
 825         unsigned total;
 826
 827         if (n == 0)
 828                 return bmap;
 829         if (!bmap)
 830                 return NULL;
 831         total = isl_basic_map_total_dim(bmap);
 832
 833         bmap = isl_basic_map_cow(bmap);
 834         for (d = pos + n - 1; d >= 0 && d >= pos; --d) {
 835                 int n_lower, n_upper;
 836                 bmap = remove_dependent_vars(bmap, d);
 837                 if (!bmap)
 838                         return NULL;
 839                 if (d >= total - bmap->n_div)
 840                         isl_seq_clr(bmap->div[d-(total-bmap->n_div)], 2+total);
 841                 for (i = 0; i < bmap->n_eq; ++i) {
 842                         if (isl_int_is_zero(bmap->eq[i][1+d]))
 843                                 continue;
 844                         eliminate_var_using_equality(bmap, d, bmap->eq[i], NULL);
 845                         isl_basic_map_drop_equality(bmap, i);
 846                         break;
 847                 }
 848                 if (i < bmap->n_eq)
 849                         continue;
 850                 n_lower = 0;
 851                 n_upper = 0;
 852                 for (i = 0; i < bmap->n_ineq; ++i) {
 853                         if (isl_int_is_pos(bmap->ineq[i][1+d]))
 854                                 n_lower++;
 855                         else if (isl_int_is_neg(bmap->ineq[i][1+d]))
 856                                 n_upper++;
 857                 }
 858                 bmap = isl_basic_map_extend_constraints(bmap,
 859                                 0, n_lower * n_upper);
 860                 for (i = bmap->n_ineq - 1; i >= 0; --i) {
 861                         int last;
 862                         if (isl_int_is_zero(bmap->ineq[i][1+d]))
 863                                 continue;
 864                         last = -1;
 865                         for (j = 0; j < i; ++j) {
 866                                 if (isl_int_is_zero(bmap->ineq[j][1+d]))
 867                                         continue;
 868                                 last = j;
 869                                 if (isl_int_sgn(bmap->ineq[i][1+d]) ==
 870                                     isl_int_sgn(bmap->ineq[j][1+d]))
 871                                         continue;
 872                                 k = isl_basic_map_alloc_inequality(bmap);
 873                                 if (k < 0)
 874                                         goto error;
 875                                 isl_seq_cpy(bmap->ineq[k], bmap->ineq[i],
 876                                                 1+total);
 877                                 isl_seq_elim(bmap->ineq[k], bmap->ineq[j],
 878                                                 1+d, 1+total, NULL);
 879                         }
 880                         isl_basic_map_drop_inequality(bmap, i);
 881                         i = last + 1;
 882                 }
 883                 if (n_lower > 0 && n_upper > 0) {
 884                         bmap = normalize_constraints(bmap);
 885                         bmap = remove_duplicate_constraints(bmap, NULL);
 886                         bmap = isl_basic_map_gauss(bmap, NULL);
 887                         bmap = isl_basic_map_convex_hull(bmap);
 888                         if (!bmap)
 889                                 goto error;
 890                         if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
 891                                 break;
 892                 }
 893         }
 894         F_CLR(bmap, ISL_BASIC_MAP_NORMALIZED);
 895         return bmap;
 896 error:
 897         isl_basic_map_free(bmap);
 898         return NULL;
 899 }
 900
 901 struct isl_basic_set *isl_basic_set_eliminate_vars(
 902         struct isl_basic_set *bset, unsigned pos, unsigned n)
 903 {
 904         return (struct isl_basic_set *)isl_basic_map_eliminate_vars(
 905                         (struct isl_basic_map *)bset, pos, n);
 906 }
 907
 908 static void compute_elimination_index(struct isl_basic_map *bmap, int *elim)
 909 {
 910         int d, i;
 911         unsigned total;
 912
 913         total = isl_dim_total(bmap->dim);
 914         for (d = 0; d < total; ++d)
 915                 elim[d] = -1;
 916         for (d = total - 1, i = 0; d >= 0 && i < bmap->n_eq; ++i) {
 917                 for (; d >= 0; --d) {
 918                         if (isl_int_is_zero(bmap->eq[i][1+d]))
 919                                 continue;
 920                         elim[d] = i;
 921                         break;
 922                 }
 923         }
 924 }
 925
 926 static void set_compute_elimination_index(struct isl_basic_set *bset, int *elim)
 927 {
 928         return compute_elimination_index((struct isl_basic_map *)bset, elim);
 929 }
 930
 931 static int reduced_using_equalities(isl_int *dst, isl_int *src,
 932         struct isl_basic_map *bmap, int *elim)
 933 {
 934         int d, i;
 935         int copied = 0;
 936         unsigned total;
 937
 938         total = isl_dim_total(bmap->dim);
 939         for (d = total - 1; d >= 0; --d) {
 940                 if (isl_int_is_zero(src[1+d]))
 941                         continue;
 942                 if (elim[d] == -1)
 943                         continue;
 944                 if (!copied) {
 945                         isl_seq_cpy(dst, src, 1 + total);
 946                         copied = 1;
 947                 }
 948                 isl_seq_elim(dst, bmap->eq[elim[d]], 1 + d, 1 + total, NULL);
 949         }
 950         return copied;
 951 }
 952
 953 static int set_reduced_using_equalities(isl_int *dst, isl_int *src,
 954         struct isl_basic_set *bset, int *elim)
 955 {
 956         return reduced_using_equalities(dst, src,
 957                                         (struct isl_basic_map *)bset, elim);
 958 }
 959
 960 static struct isl_basic_set *isl_basic_set_reduce_using_equalities(
 961         struct isl_basic_set *bset, struct isl_basic_set *context)
 962 {
 963         int i;
 964         int *elim;
 965
 966         if (!bset || !context)
 967                 goto error;
 968
 969         bset = isl_basic_set_cow(bset);
 970         if (!bset)
 971                 goto error;
 972
 973         elim = isl_alloc_array(ctx, int, isl_basic_set_n_dim(bset));
 974         if (!elim)
 975                 goto error;
 976         set_compute_elimination_index(context, elim);
 977         for (i = 0; i < bset->n_eq; ++i)
 978                 set_reduced_using_equalities(bset->eq[i], bset->eq[i],
 979                                                         context, elim);
 980         for (i = 0; i < bset->n_ineq; ++i)
 981                 set_reduced_using_equalities(bset->ineq[i], bset->ineq[i],
 982                                                         context, elim);
 983         isl_basic_set_free(context);
 984         free(elim);
 985         bset = isl_basic_set_simplify(bset);
 986         bset = isl_basic_set_finalize(bset);
 987         return bset;
 988 error:
 989         isl_basic_set_free(bset);
 990         isl_basic_set_free(context);
 991         return NULL;
 992 }
 993
 994 static struct isl_basic_set *remove_shifted_constraints(
 995         struct isl_basic_set *bset, struct isl_basic_set *context)
 996 {
 997         unsigned int size;
 998         isl_int ***index;
 999         int bits;
1000         int k, h, l;
1001
1002         if (!bset)
1003                 return NULL;
1004
1005         size = round_up(4 * (context->n_ineq+1) / 3 - 1);
1006         bits = ffs(size) - 1;
1007         index = isl_calloc_array(ctx, isl_int **, size);
1008         if (!index)
1009                 return bset;
1010
1011         for (k = 0; k < context->n_ineq; ++k) {
1012                 h = set_hash_index(index, size, bits, context, k);
1013                 index[h] = &context->ineq[k];
1014         }
1015         for (k = 0; k < bset->n_ineq; ++k) {
1016                 h = set_hash_index(index, size, bits, bset, k);
1017                 if (!index[h])
1018                         continue;
1019                 l = index[h] - &context->ineq[0];
1020                 if (isl_int_lt(bset->ineq[k][0], context->ineq[l][0]))
1021                         continue;
1022                 bset = isl_basic_set_cow(bset);
1023                 if (!bset)
1024                         goto error;
1025                 isl_basic_set_drop_inequality(bset, k);
1026                 --k;
1027         }
1028         free(index);
1029         return bset;
1030 error:
1031         free(index);
1032         return bset;
1033 }
1034
1035 static struct isl_basic_set *uset_gist(struct isl_basic_set *bset,
1036         struct isl_basic_set *context);
1037
1038 static struct isl_basic_set *uset_gist_context_eq(struct isl_basic_set *bset,
1039         struct isl_basic_set *context)
1040 {
1041         struct isl_mat *T;
1042         struct isl_mat *T2;
1043         struct isl_ctx *ctx = context->ctx;
1044         struct isl_basic_set *reduced_context;
1045         reduced_context = isl_basic_set_remove_equalities(
1046                                 isl_basic_set_copy(context), &T, &T2);
1047         if (!reduced_context)
1048                 goto error;
1049         bset = isl_basic_set_preimage(ctx, bset, T);
1050         bset = uset_gist(bset, reduced_context);
1051         bset = isl_basic_set_preimage(ctx, bset, T2);
1052         bset = isl_basic_set_reduce_using_equalities(bset, context);
1053         return bset;
1054 error:
1055         isl_basic_set_free(context);
1056         isl_basic_set_free(bset);
1057         return NULL;
1058 }
1059
1060 static struct isl_basic_set *uset_gist_set_eq(struct isl_basic_set *bset,
1061         struct isl_basic_set *context)
1062 {
1063         struct isl_mat *T;
1064         struct isl_mat *T2;
1065         struct isl_ctx *ctx = context->ctx;
1066         struct isl_basic_set *affine_hull = NULL;
1067
1068         affine_hull = isl_basic_set_copy(bset);
1069         affine_hull = isl_basic_set_cow(affine_hull);
1070         if (!affine_hull)
1071                 goto error;
1072         isl_basic_set_free_inequality(affine_hull, affine_hull->n_ineq);
1073
1074         bset = isl_basic_set_remove_equalities(bset, &T, &T2);
1075         if (!bset)
1076                 goto error;
1077         context = isl_basic_set_preimage(ctx, context, T);
1078         bset = uset_gist(bset, context);
1079         bset = isl_basic_set_preimage(ctx, bset, T2);
1080         bset = isl_basic_set_intersect(bset, affine_hull);
1081         return bset;
1082 error:
1083         isl_basic_set_free(affine_hull);
1084         isl_basic_set_free(context);
1085         isl_basic_set_free(bset);
1086         return NULL;
1087 }
1088
1089 /* Remove all information from bset that is redundant in the context
1090  * of context.  In particular, equalities that are linear combinations
1091  * of those in context are removed.  Then the inequalities that are
1092  * redundant in the context of the equalities and inequalities of
1093  * context are removed.
1094  */
1095 static struct isl_basic_set *uset_gist(struct isl_basic_set *bset,
1096         struct isl_basic_set *context)
1097 {
1098         int i;
1099         isl_int opt;
1100         struct isl_basic_set *combined;
1101         struct isl_ctx *ctx;
1102
1103         if (!bset || !context)
1104                 goto error;
1105
1106         if (context->n_eq > 0)
1107                 return uset_gist_context_eq(bset, context);
1108         if (!context->n_ineq)
1109                 goto done;
1110         if (bset->n_eq > 0)
1111                 return uset_gist_set_eq(bset, context);
1112         bset = remove_shifted_constraints(bset, context);
1113         combined = isl_basic_set_extend_constraints(isl_basic_set_copy(bset),
1114                         context->n_eq, context->n_ineq);
1115         context = isl_basic_set_add_constraints(combined, context, 0);
1116         if (!context)
1117                 goto error;
1118         ctx = context->ctx;
1119         isl_int_init(opt);
1120         for (i = bset->n_ineq-1; i >= 0; --i) {
1121                 int redundant;
1122                 set_swap_inequality(context, i, context->n_ineq-1);
1123                 context->n_ineq--;
1124                 redundant = isl_basic_set_constraint_is_redundant(&context,
1125                                 context->ineq[context->n_ineq], &opt, NULL);
1126                 if (redundant == -1) {
1127                         isl_int_clear(opt);
1128                         goto error;
1129                 }
1130                 if (F_ISSET(context, ISL_BASIC_MAP_EMPTY)) {
1131                         bset = isl_basic_set_set_to_empty(bset);
1132                         break;
1133                 }
1134                 context->n_ineq++;
1135                 set_swap_inequality(context, i, context->n_ineq-1);
1136                 if (redundant) {
1137                         isl_basic_set_drop_inequality(context, i);
1138                         isl_basic_set_drop_inequality(bset, i);
1139                 }
1140         }
1141         isl_int_clear(opt);
1142 done:
1143         isl_basic_set_free(context);
1144         return bset;
1145 error:
1146         isl_basic_set_free(context);
1147         isl_basic_set_free(bset);
1148         return NULL;
1149 }
1150
1151 struct isl_basic_map *isl_basic_map_gist(struct isl_basic_map *bmap,
1152         struct isl_basic_map *context)
1153 {
1154         struct isl_basic_set *bset;
1155
1156         if (!bmap || !context)
1157                 goto error;
1158
1159         context = isl_basic_map_align_divs(context, bmap);
1160         bmap = isl_basic_map_align_divs(bmap, context);
1161
1162         bset = uset_gist(isl_basic_map_underlying_set(isl_basic_map_copy(bmap)),
1163                          isl_basic_map_underlying_set(context));
1164
1165         return isl_basic_map_overlying_set(bset, bmap);
1166 error:
1167         isl_basic_map_free(bmap);
1168         isl_basic_map_free(context);
1169         return NULL;
1170 }
1171
1172 /*
1173  * Assumes context has no implicit divs.
1174  */
1175 struct isl_map *isl_map_gist(struct isl_map *map, struct isl_basic_map *context)
1176 {
1177         int i;
1178
1179         map = isl_map_cow(map);
1180         if (!map || !context)
1181                 return NULL;
1182         isl_assert(map->ctx, isl_dim_equal(map->dim, context->dim), goto error);
1183         map = isl_map_compute_divs(map);
1184         for (i = 0; i < map->n; ++i)
1185                 context = isl_basic_map_align_divs(context, map->p[i]);
1186         for (i = 0; i < map->n; ++i) {
1187                 map->p[i] = isl_basic_map_gist(map->p[i],
1188                                                 isl_basic_map_copy(context));
1189                 if (!map->p[i])
1190                         goto error;
1191         }
1192         isl_basic_map_free(context);
1193         F_CLR(map, ISL_MAP_NORMALIZED);
1194         return map;
1195 error:
1196         isl_map_free(map);
1197         isl_basic_map_free(context);
1198         return NULL;
1199 }
1200
1201 struct isl_basic_set *isl_basic_set_gist(struct isl_basic_set *bset,
1202                                                 struct isl_basic_set *context)
1203 {
1204         return (struct isl_basic_set *)isl_basic_map_gist(
1205                 (struct isl_basic_map *)bset, (struct isl_basic_map *)context);
1206 }
1207
1208 struct isl_set *isl_set_gist(struct isl_set *set, struct isl_basic_set *context)
1209 {
1210         return (struct isl_set *)isl_map_gist((struct isl_map *)set,
1211                                         (struct isl_basic_map *)context);
1212 }
1213
1214 /* Quick check to see if two basic maps are disjoint.
1215  * In particular, we reduce the equalities and inequalities of
1216  * one basic map in the context of the equalities of the other
1217  * basic map and check if we get a contradiction.
1218  */
1219 int isl_basic_map_fast_is_disjoint(struct isl_basic_map *bmap1,
1220         struct isl_basic_map *bmap2)
1221 {
1222         struct isl_vec *v = NULL;
1223         int *elim = NULL;
1224         unsigned total;
1225         int d, i;
1226
1227         if (!bmap1 || !bmap2)
1228                 return -1;
1229         isl_assert(bmap1->ctx, isl_dim_equal(bmap1->dim, bmap2->dim),
1230                         return -1);
1231         if (bmap1->n_div || bmap2->n_div)
1232                 return 0;
1233         if (!bmap1->n_eq && !bmap2->n_eq)
1234                 return 0;
1235
1236         total = isl_dim_total(bmap1->dim);
1237         if (total == 0)
1238                 return 0;
1239         v = isl_vec_alloc(bmap1->ctx, 1 + total);
1240         if (!v)
1241                 goto error;
1242         elim = isl_alloc_array(bmap1->ctx, int, total);
1243         if (!elim)
1244                 goto error;
1245         compute_elimination_index(bmap1, elim);
1246         for (i = 0; i < bmap2->n_eq; ++i) {
1247                 int reduced;
1248                 reduced = reduced_using_equalities(v->block.data, bmap2->eq[i],
1249                                                         bmap1, elim);
1250                 if (reduced && !isl_int_is_zero(v->block.data[0]) &&
1251                     isl_seq_first_non_zero(v->block.data + 1, total) == -1)
1252                         goto disjoint;
1253         }
1254         for (i = 0; i < bmap2->n_ineq; ++i) {
1255                 int reduced;
1256                 reduced = reduced_using_equalities(v->block.data,
1257                                                 bmap2->ineq[i], bmap1, elim);
1258                 if (reduced && isl_int_is_neg(v->block.data[0]) &&
1259                     isl_seq_first_non_zero(v->block.data + 1, total) == -1)
1260                         goto disjoint;
1261         }
1262         compute_elimination_index(bmap2, elim);
1263         for (i = 0; i < bmap1->n_ineq; ++i) {
1264                 int reduced;
1265                 reduced = reduced_using_equalities(v->block.data,
1266                                                 bmap1->ineq[i], bmap2, elim);
1267                 if (reduced && isl_int_is_neg(v->block.data[0]) &&
1268                     isl_seq_first_non_zero(v->block.data + 1, total) == -1)
1269                         goto disjoint;
1270         }
1271         isl_vec_free(bmap1->ctx, v);
1272         free(elim);
1273         return 0;
1274 disjoint:
1275         isl_vec_free(bmap1->ctx, v);
1276         free(elim);
1277         return 1;
1278 error:
1279         isl_vec_free(bmap1->ctx, v);
1280         free(elim);
1281         return -1;
1282 }
1283
1284 int isl_basic_set_fast_is_disjoint(struct isl_basic_set *bset1,
1285         struct isl_basic_set *bset2)
1286 {
1287         return isl_basic_map_fast_is_disjoint((struct isl_basic_map *)bset1,
1288                                               (struct isl_basic_map *)bset2);
1289 }
1290
1291 int isl_map_fast_is_disjoint(struct isl_map *map1, struct isl_map *map2)
1292 {
1293         int i, j;
1294
1295         if (!map1 || !map2)
1296                 return -1;
1297
1298         if (isl_map_fast_is_equal(map1, map2))
1299                 return 0;
1300
1301         for (i = 0; i < map1->n; ++i) {
1302                 for (j = 0; j < map2->n; ++j) {
1303                         int d = isl_basic_map_fast_is_disjoint(map1->p[i],
1304                                                                map2->p[j]);
1305                         if (d != 1)
1306                                 return d;
1307                 }
1308         }
1309         return 1;
1310 }
1311
1312 int isl_set_fast_is_disjoint(struct isl_set *set1, struct isl_set *set2)
1313 {
1314         return isl_map_fast_is_disjoint((struct isl_map *)set1,
1315                                         (struct isl_map *)set2);
1316 }