isl_map.c

   1 #include <string.h>
   2 #include <strings.h>
   3 #include "isl_ctx.h"
   4 #include "isl_blk.h"
   5 #include "isl_seq.h"
   6 #include "isl_set.h"
   7 #include "isl_map.h"
   8 #include "isl_map_private.h"
   9 #include "isl_map_piplib.h"
  10 #include "isl_sample.h"
  11 #include "isl_vec.h"
  12
  13 static struct isl_basic_map *basic_map_init(struct isl_ctx *ctx,
  14                 struct isl_basic_map *bmap,
  15                 unsigned nparam, unsigned n_in, unsigned n_out, unsigned extra,
  16                 unsigned n_eq, unsigned n_ineq)
  17 {
  18         int i;
  19         size_t row_size = 1 + nparam + n_in + n_out + extra;
  20
  21         bmap->block = isl_blk_alloc(ctx, (n_eq + n_ineq) * row_size);
  22         if (isl_blk_is_error(bmap->block)) {
  23                 free(bmap);
  24                 return NULL;
  25         }
  26
  27         bmap->eq = isl_alloc_array(ctx, isl_int *, n_eq + n_ineq);
  28         if (!bmap->eq) {
  29                 isl_blk_free(ctx, bmap->block);
  30                 free(bmap);
  31                 return NULL;
  32         }
  33
  34         if (extra == 0) {
  35                 bmap->block2 = isl_blk_empty();
  36                 bmap->div = NULL;
  37         } else {
  38                 bmap->block2 = isl_blk_alloc(ctx, extra * (1 + row_size));
  39                 if (isl_blk_is_error(bmap->block2)) {
  40                         free(bmap->eq);
  41                         isl_blk_free(ctx, bmap->block);
  42                         free(bmap);
  43                         return NULL;
  44                 }
  45
  46                 bmap->div = isl_alloc_array(ctx, isl_int *, extra);
  47                 if (!bmap->div) {
  48                         isl_blk_free(ctx, bmap->block2);
  49                         free(bmap->eq);
  50                         isl_blk_free(ctx, bmap->block);
  51                         free(bmap);
  52                         return NULL;
  53                 }
  54         }
  55
  56         for (i = 0; i < n_eq + n_ineq; ++i)
  57                 bmap->eq[i] = bmap->block.data + i * row_size;
  58
  59         for (i = 0; i < extra; ++i)
  60                 bmap->div[i] = bmap->block2.data + i * (1 + row_size);
  61
  62         bmap->ctx = ctx;
  63         isl_ctx_ref(ctx);
  64         bmap->ref = 1;
  65         bmap->flags = 0;
  66         bmap->c_size = n_eq + n_ineq;
  67         bmap->ineq = bmap->eq + n_eq;
  68         bmap->nparam = nparam;
  69         bmap->n_in = n_in;
  70         bmap->n_out = n_out;
  71         bmap->extra = extra;
  72         bmap->n_eq = 0;
  73         bmap->n_ineq = 0;
  74         bmap->n_div = 0;
  75         bmap->sample = NULL;
  76
  77         return bmap;
  78 }
  79
  80 struct isl_basic_set *isl_basic_set_alloc(struct isl_ctx *ctx,
  81                 unsigned nparam, unsigned dim, unsigned extra,
  82                 unsigned n_eq, unsigned n_ineq)
  83 {
  84         struct isl_basic_map *bmap;
  85         bmap = isl_basic_map_alloc(ctx, nparam, 0, dim, extra, n_eq, n_ineq);
  86         return (struct isl_basic_set *)bmap;
  87 }
  88
  89 struct isl_basic_map *isl_basic_map_alloc(struct isl_ctx *ctx,
  90                 unsigned nparam, unsigned in, unsigned out, unsigned extra,
  91                 unsigned n_eq, unsigned n_ineq)
  92 {
  93         struct isl_basic_map *bmap;
  94
  95         bmap = isl_alloc_type(ctx, struct isl_basic_map);
  96         if (!bmap)
  97                 return NULL;
  98
  99         return basic_map_init(ctx, bmap,
 100                                nparam, in, out, extra, n_eq, n_ineq);
 101 }
 102
 103 static void dup_constraints(
 104                 struct isl_basic_map *dst, struct isl_basic_map *src)
 105 {
 106         int i;
 107         unsigned total = src->nparam + src->n_in + src->n_out + src->n_div;
 108
 109         for (i = 0; i < src->n_eq; ++i) {
 110                 int j = isl_basic_map_alloc_equality(dst);
 111                 isl_seq_cpy(dst->eq[j], src->eq[i], 1+total);
 112         }
 113
 114         for (i = 0; i < src->n_ineq; ++i) {
 115                 int j = isl_basic_map_alloc_inequality(dst);
 116                 isl_seq_cpy(dst->ineq[j], src->ineq[i], 1+total);
 117         }
 118
 119         for (i = 0; i < src->n_div; ++i) {
 120                 int j = isl_basic_map_alloc_div(dst);
 121                 isl_seq_cpy(dst->div[j], src->div[i], 1+1+total);
 122         }
 123         F_SET(dst, ISL_BASIC_SET_FINAL);
 124 }
 125
 126 struct isl_basic_map *isl_basic_map_dup(struct isl_basic_map *bmap)
 127 {
 128         struct isl_basic_map *dup;
 129
 130         if (!bmap)
 131                 return NULL;
 132         dup = isl_basic_map_alloc(bmap->ctx, bmap->nparam,
 133                         bmap->n_in, bmap->n_out,
 134                         bmap->n_div, bmap->n_eq, bmap->n_ineq);
 135         if (!dup)
 136                 return NULL;
 137         dup->flags = bmap->flags;
 138         dup_constraints(dup, bmap);
 139         dup->sample = isl_vec_copy(bmap->ctx, bmap->sample);
 140         return dup;
 141 }
 142
 143 struct isl_basic_set *isl_basic_set_dup(struct isl_basic_set *bset)
 144 {
 145         struct isl_basic_map *dup;
 146
 147         dup = isl_basic_map_dup((struct isl_basic_map *)bset);
 148         return (struct isl_basic_set *)dup;
 149 }
 150
 151 struct isl_basic_set *isl_basic_set_copy(struct isl_basic_set *bset)
 152 {
 153         if (!bset)
 154                 return NULL;
 155
 156         if (F_ISSET(bset, ISL_BASIC_SET_FINAL)) {
 157                 bset->ref++;
 158                 return bset;
 159         }
 160         return isl_basic_set_dup(bset);
 161 }
 162
 163 struct isl_set *isl_set_copy(struct isl_set *set)
 164 {
 165         if (!set)
 166                 return NULL;
 167
 168         set->ref++;
 169         return set;
 170 }
 171
 172 struct isl_basic_map *isl_basic_map_copy(struct isl_basic_map *bmap)
 173 {
 174         if (!bmap)
 175                 return NULL;
 176
 177         if (F_ISSET(bmap, ISL_BASIC_SET_FINAL)) {
 178                 bmap->ref++;
 179                 return bmap;
 180         }
 181         return isl_basic_map_dup(bmap);
 182 }
 183
 184 struct isl_map *isl_map_copy(struct isl_map *map)
 185 {
 186         if (!map)
 187                 return NULL;
 188
 189         map->ref++;
 190         return map;
 191 }
 192
 193 void isl_basic_map_free(struct isl_basic_map *bmap)
 194 {
 195         if (!bmap)
 196                 return;
 197
 198         if (--bmap->ref > 0)
 199                 return;
 200
 201         isl_ctx_deref(bmap->ctx);
 202         free(bmap->div);
 203         isl_blk_free(bmap->ctx, bmap->block2);
 204         free(bmap->eq);
 205         isl_blk_free(bmap->ctx, bmap->block);
 206         isl_vec_free(bmap->ctx, bmap->sample);
 207         free(bmap);
 208 }
 209
 210 void isl_basic_set_free(struct isl_basic_set *bset)
 211 {
 212         isl_basic_map_free((struct isl_basic_map *)bset);
 213 }
 214
 215 int isl_basic_map_alloc_equality(struct isl_basic_map *bmap)
 216 {
 217         struct isl_ctx *ctx;
 218         if (!bmap)
 219                 return -1;
 220         ctx = bmap->ctx;
 221         isl_assert(ctx, bmap->n_eq + bmap->n_ineq < bmap->c_size, return -1);
 222         isl_assert(ctx, bmap->eq + bmap->n_eq <= bmap->ineq, return -1);
 223         if (bmap->eq + bmap->n_eq == bmap->ineq) {
 224                 isl_int *t;
 225                 int j = isl_basic_map_alloc_inequality(bmap);
 226                 if (j < 0)
 227                         return -1;
 228                 t = bmap->ineq[0];
 229                 bmap->ineq[0] = bmap->ineq[j];
 230                 bmap->ineq[j] = t;
 231                 bmap->n_ineq--;
 232                 bmap->ineq++;
 233         }
 234         return bmap->n_eq++;
 235 }
 236
 237 int isl_basic_set_alloc_equality(struct isl_basic_set *bset)
 238 {
 239         return isl_basic_map_alloc_equality((struct isl_basic_map *)bset);
 240 }
 241
 242 int isl_basic_map_free_equality(struct isl_basic_map *bmap, unsigned n)
 243 {
 244         if (!bmap)
 245                 return -1;
 246         isl_assert(bmap->ctx, n <= bmap->n_eq, return -1);
 247         bmap->n_eq -= n;
 248         return 0;
 249 }
 250
 251 int isl_basic_map_drop_equality(struct isl_basic_map *bmap, unsigned pos)
 252 {
 253         isl_int *t;
 254         if (!bmap)
 255                 return -1;
 256         isl_assert(bmap->ctx, pos < bmap->n_eq, return -1);
 257
 258         if (pos != bmap->n_eq - 1) {
 259                 t = bmap->eq[pos];
 260                 bmap->eq[pos] = bmap->eq[bmap->n_eq - 1];
 261                 bmap->eq[bmap->n_eq - 1] = t;
 262         }
 263         bmap->n_eq--;
 264         return 0;
 265 }
 266
 267 int isl_basic_set_drop_equality(struct isl_basic_set *bset, unsigned pos)
 268 {
 269         return isl_basic_map_drop_equality((struct isl_basic_map *)bset, pos);
 270 }
 271
 272 void isl_basic_map_inequality_to_equality(
 273                 struct isl_basic_map *bmap, unsigned pos)
 274 {
 275         isl_int *t;
 276
 277         t = bmap->ineq[pos];
 278         bmap->ineq[pos] = bmap->ineq[0];
 279         bmap->ineq[0] = bmap->eq[bmap->n_eq];
 280         bmap->eq[bmap->n_eq] = t;
 281         bmap->n_eq++;
 282         bmap->n_ineq--;
 283         bmap->ineq++;
 284 }
 285
 286 int isl_basic_map_alloc_inequality(struct isl_basic_map *bmap)
 287 {
 288         struct isl_ctx *ctx;
 289         if (!bmap)
 290                 return -1;
 291         ctx = bmap->ctx;
 292         isl_assert(ctx, (bmap->ineq - bmap->eq) + bmap->n_ineq < bmap->c_size,
 293                         return -1);
 294         F_CLR(bmap, ISL_BASIC_MAP_NO_IMPLICIT);
 295         F_CLR(bmap, ISL_BASIC_MAP_NO_REDUNDANT);
 296         return bmap->n_ineq++;
 297 }
 298
 299 int isl_basic_set_alloc_inequality(struct isl_basic_set *bset)
 300 {
 301         return isl_basic_map_alloc_inequality((struct isl_basic_map *)bset);
 302 }
 303
 304 int isl_basic_map_free_inequality(struct isl_basic_map *bmap, unsigned n)
 305 {
 306         if (!bmap)
 307                 return -1;
 308         isl_assert(bmap->ctx, n <= bmap->n_ineq, return -1);
 309         bmap->n_ineq -= n;
 310         return 0;
 311 }
 312
 313 int isl_basic_set_free_inequality(struct isl_basic_set *bset, unsigned n)
 314 {
 315         return isl_basic_map_free_inequality((struct isl_basic_map *)bset, n);
 316 }
 317
 318 int isl_basic_map_drop_inequality(struct isl_basic_map *bmap, unsigned pos)
 319 {
 320         isl_int *t;
 321         if (!bmap)
 322                 return -1;
 323         isl_assert(bmap->ctx, pos < bmap->n_ineq, return -1);
 324
 325         if (pos != bmap->n_ineq - 1) {
 326                 t = bmap->ineq[pos];
 327                 bmap->ineq[pos] = bmap->ineq[bmap->n_ineq - 1];
 328                 bmap->ineq[bmap->n_ineq - 1] = t;
 329         }
 330         bmap->n_ineq--;
 331         return 0;
 332 }
 333
 334 int isl_basic_set_drop_inequality(struct isl_basic_set *bset, unsigned pos)
 335 {
 336         return isl_basic_map_drop_inequality((struct isl_basic_map *)bset, pos);
 337 }
 338
 339 int isl_basic_map_alloc_div(struct isl_basic_map *bmap)
 340 {
 341         if (!bmap)
 342                 return -1;
 343         isl_assert(bmap->ctx, bmap->n_div < bmap->extra, return -1);
 344         return bmap->n_div++;
 345 }
 346
 347 int isl_basic_map_free_div(struct isl_basic_map *bmap, unsigned n)
 348 {
 349         if (!bmap)
 350                 return -1;
 351         isl_assert(bmap->ctx, n <= bmap->n_div, return -1);
 352         bmap->n_div -= n;
 353         return 0;
 354 }
 355
 356 /* Copy constraint from src to dst, putting the vars of src at offset
 357  * dim_off in dst and the divs of src at offset div_off in dst.
 358  * If both sets are actually map, then dim_off applies to the input
 359  * variables.
 360  */
 361 static void copy_constraint(struct isl_basic_map *dst_map, isl_int *dst,
 362                             struct isl_basic_map *src_map, isl_int *src,
 363                             unsigned in_off, unsigned out_off, unsigned div_off)
 364 {
 365         isl_int_set(dst[0], src[0]);
 366         isl_seq_cpy(dst+1, src+1, isl_min(dst_map->nparam, src_map->nparam));
 367         if (dst_map->nparam > src_map->nparam)
 368                 isl_seq_clr(dst+1+src_map->nparam,
 369                                 dst_map->nparam - src_map->nparam);
 370         isl_seq_clr(dst+1+dst_map->nparam, in_off);
 371         isl_seq_cpy(dst+1+dst_map->nparam+in_off,
 372                     src+1+src_map->nparam,
 373                     isl_min(dst_map->n_in-in_off, src_map->n_in));
 374         if (dst_map->n_in-in_off > src_map->n_in)
 375                 isl_seq_clr(dst+1+dst_map->nparam+in_off+src_map->n_in,
 376                                 dst_map->n_in - in_off - src_map->n_in);
 377         isl_seq_clr(dst+1+dst_map->nparam+dst_map->n_in, out_off);
 378         isl_seq_cpy(dst+1+dst_map->nparam+dst_map->n_in+out_off,
 379                     src+1+src_map->nparam+src_map->n_in,
 380                     isl_min(dst_map->n_out-out_off, src_map->n_out));
 381         if (dst_map->n_out-out_off > src_map->n_out)
 382                 isl_seq_clr(dst+1+dst_map->nparam+dst_map->n_in+out_off+src_map->n_out,
 383                                 dst_map->n_out - out_off - src_map->n_out);
 384         isl_seq_clr(dst+1+dst_map->nparam+dst_map->n_in+dst_map->n_out, div_off);
 385         isl_seq_cpy(dst+1+dst_map->nparam+dst_map->n_in+dst_map->n_out+div_off,
 386                     src+1+src_map->nparam+src_map->n_in+src_map->n_out,
 387                     isl_min(dst_map->extra-div_off, src_map->extra));
 388         if (dst_map->extra-div_off > src_map->extra)
 389                 isl_seq_clr(dst+1+dst_map->nparam+dst_map->n_in+dst_map->n_out+
 390                                 div_off+src_map->extra,
 391                                 dst_map->extra - div_off - src_map->extra);
 392 }
 393
 394 static void copy_div(struct isl_basic_map *dst_map, isl_int *dst,
 395                      struct isl_basic_map *src_map, isl_int *src,
 396                      unsigned in_off, unsigned out_off, unsigned div_off)
 397 {
 398         isl_int_set(dst[0], src[0]);
 399         copy_constraint(dst_map, dst+1, src_map, src+1, in_off, out_off, div_off);
 400 }
 401
 402 static struct isl_basic_map *add_constraints(struct isl_basic_map *bmap1,
 403                 struct isl_basic_map *bmap2, unsigned i_pos, unsigned o_pos)
 404 {
 405         int i;
 406         unsigned div_off = bmap1->n_div;
 407
 408         for (i = 0; i < bmap2->n_eq; ++i) {
 409                 int i1 = isl_basic_map_alloc_equality(bmap1);
 410                 if (i1 < 0)
 411                         goto error;
 412                 copy_constraint(bmap1, bmap1->eq[i1], bmap2, bmap2->eq[i],
 413                                 i_pos, o_pos, div_off);
 414         }
 415
 416         for (i = 0; i < bmap2->n_ineq; ++i) {
 417                 int i1 = isl_basic_map_alloc_inequality(bmap1);
 418                 if (i1 < 0)
 419                         goto error;
 420                 copy_constraint(bmap1, bmap1->ineq[i1], bmap2, bmap2->ineq[i],
 421                                 i_pos, o_pos, div_off);
 422         }
 423
 424         for (i = 0; i < bmap2->n_div; ++i) {
 425                 int i1 = isl_basic_map_alloc_div(bmap1);
 426                 if (i1 < 0)
 427                         goto error;
 428                 copy_div(bmap1, bmap1->div[i1], bmap2, bmap2->div[i],
 429                          i_pos, o_pos, div_off);
 430         }
 431
 432         isl_basic_map_free(bmap2);
 433
 434         return bmap1;
 435
 436 error:
 437         isl_basic_map_free(bmap1);
 438         isl_basic_map_free(bmap2);
 439         return NULL;
 440 }
 441
 442 struct isl_basic_map *isl_basic_map_extend(struct isl_basic_map *base,
 443                 unsigned nparam, unsigned n_in, unsigned n_out, unsigned extra,
 444                 unsigned n_eq, unsigned n_ineq)
 445 {
 446         struct isl_basic_map *ext;
 447         unsigned flags;
 448         int dims_ok;
 449
 450         base = isl_basic_map_cow(base);
 451         if (!base)
 452                 goto error;
 453
 454         dims_ok = base && base->nparam == nparam &&
 455                   base->n_in == n_in && base->n_out == n_out &&
 456                   base->extra >= base->n_div + extra;
 457
 458         if (dims_ok && n_eq == 0 && n_ineq == 0)
 459                 return base;
 460
 461         isl_assert(base->ctx, base->nparam <= nparam, goto error);
 462         isl_assert(base->ctx, base->n_in <= n_in, goto error);
 463         isl_assert(base->ctx, base->n_out <= n_out, goto error);
 464         extra += base->extra;
 465         n_eq += base->n_eq;
 466         n_ineq += base->n_ineq;
 467
 468         ext = isl_basic_map_alloc(base->ctx, nparam, n_in, n_out,
 469                                         extra, n_eq, n_ineq);
 470         if (!base)
 471                 return ext;
 472         if (!ext)
 473                 goto error;
 474
 475         flags = base->flags;
 476         ext = add_constraints(ext, base, 0, 0);
 477         if (ext) {
 478                 ext->flags = flags;
 479                 F_CLR(ext, ISL_BASIC_SET_FINAL);
 480         }
 481
 482         return ext;
 483
 484 error:
 485         isl_basic_map_free(base);
 486         return NULL;
 487 }
 488
 489 struct isl_basic_set *isl_basic_set_extend(struct isl_basic_set *base,
 490                 unsigned nparam, unsigned dim, unsigned extra,
 491                 unsigned n_eq, unsigned n_ineq)
 492 {
 493         return (struct isl_basic_set *)
 494                 isl_basic_map_extend((struct isl_basic_map *)base,
 495                                         nparam, 0, dim, extra, n_eq, n_ineq);
 496 }
 497
 498 struct isl_basic_set *isl_basic_set_cow(struct isl_basic_set *bset)
 499 {
 500         return (struct isl_basic_set *)
 501                 isl_basic_map_cow((struct isl_basic_map *)bset);
 502 }
 503
 504 struct isl_basic_map *isl_basic_map_cow(struct isl_basic_map *bmap)
 505 {
 506         if (!bmap)
 507                 return NULL;
 508
 509         if (bmap->ref > 1) {
 510                 bmap->ref--;
 511                 bmap = isl_basic_map_dup(bmap);
 512         }
 513         F_CLR(bmap, ISL_BASIC_SET_FINAL);
 514         return bmap;
 515 }
 516
 517 struct isl_set *isl_set_cow(struct isl_set *set)
 518 {
 519         if (!set)
 520                 return NULL;
 521
 522         if (set->ref == 1)
 523                 return set;
 524         set->ref--;
 525         return isl_set_dup(set);
 526 }
 527
 528 struct isl_map *isl_map_cow(struct isl_map *map)
 529 {
 530         if (!map)
 531                 return NULL;
 532
 533         if (map->ref == 1)
 534                 return map;
 535         map->ref--;
 536         return isl_map_dup(map);
 537 }
 538
 539 static void swap_vars(struct isl_blk blk, isl_int *a,
 540                         unsigned a_len, unsigned b_len)
 541 {
 542         isl_seq_cpy(blk.data, a+a_len, b_len);
 543         isl_seq_cpy(blk.data+b_len, a, a_len);
 544         isl_seq_cpy(a, blk.data, b_len+a_len);
 545 }
 546
 547 struct isl_basic_set *isl_basic_set_swap_vars(
 548                 struct isl_basic_set *bset, unsigned n)
 549 {
 550         int i;
 551         struct isl_blk blk;
 552
 553         if (!bset)
 554                 goto error;
 555
 556         isl_assert(bset->ctx, n <= bset->dim, goto error);
 557
 558         if (n == bset->dim)
 559                 return bset;
 560
 561         bset = isl_basic_set_cow(bset);
 562         if (!bset)
 563                 return NULL;
 564
 565         blk = isl_blk_alloc(bset->ctx, bset->dim);
 566         if (isl_blk_is_error(blk))
 567                 goto error;
 568
 569         for (i = 0; i < bset->n_eq; ++i)
 570                 swap_vars(blk,
 571                           bset->eq[i]+1+bset->nparam, n, bset->dim - n);
 572
 573         for (i = 0; i < bset->n_ineq; ++i)
 574                 swap_vars(blk,
 575                           bset->ineq[i]+1+bset->nparam, n, bset->dim - n);
 576
 577         for (i = 0; i < bset->n_div; ++i)
 578                 swap_vars(blk,
 579                           bset->div[i]+1+1+bset->nparam, n, bset->dim - n);
 580
 581         isl_blk_free(bset->ctx, blk);
 582
 583         return bset;
 584
 585 error:
 586         isl_basic_set_free(bset);
 587         return NULL;
 588 }
 589
 590 struct isl_set *isl_set_swap_vars(struct isl_set *set, unsigned n)
 591 {
 592         int i;
 593         set = isl_set_cow(set);
 594         if (!set)
 595                 return NULL;
 596
 597         for (i = 0; i < set->n; ++i) {
 598                 set->p[i] = isl_basic_set_swap_vars(set->p[i], n);
 599                 if (!set->p[i]) {
 600                         isl_set_free(set);
 601                         return NULL;
 602                 }
 603         }
 604         return set;
 605 }
 606
 607 static void constraint_drop_vars(isl_int *c, unsigned n, unsigned rem)
 608 {
 609         isl_seq_cpy(c, c + n, rem);
 610         isl_seq_clr(c + rem, n);
 611 }
 612
 613 struct isl_basic_set *isl_basic_set_drop_dims(
 614                 struct isl_basic_set *bset, unsigned first, unsigned n)
 615 {
 616         int i;
 617
 618         if (!bset)
 619                 goto error;
 620
 621         isl_assert(bset->ctx, first + n <= bset->dim, goto error);
 622
 623         if (n == 0)
 624                 return bset;
 625
 626         bset = isl_basic_set_cow(bset);
 627         if (!bset)
 628                 return NULL;
 629
 630         for (i = 0; i < bset->n_eq; ++i)
 631                 constraint_drop_vars(bset->eq[i]+1+bset->nparam+first, n,
 632                                      (bset->dim-first-n)+bset->extra);
 633
 634         for (i = 0; i < bset->n_ineq; ++i)
 635                 constraint_drop_vars(bset->ineq[i]+1+bset->nparam+first, n,
 636                                      (bset->dim-first-n)+bset->extra);
 637
 638         for (i = 0; i < bset->n_div; ++i)
 639                 constraint_drop_vars(bset->div[i]+1+1+bset->nparam+first, n,
 640                                      (bset->dim-first-n)+bset->extra);
 641
 642         bset->dim -= n;
 643         bset->extra += n;
 644
 645         return isl_basic_set_finalize(bset);
 646 error:
 647         isl_basic_set_free(bset);
 648         return NULL;
 649 }
 650
 651 static struct isl_set *isl_set_drop_dims(
 652                 struct isl_set *set, unsigned first, unsigned n)
 653 {
 654         int i;
 655
 656         if (!set)
 657                 goto error;
 658
 659         isl_assert(set->ctx, first + n <= set->dim, goto error);
 660
 661         if (n == 0)
 662                 return set;
 663         set = isl_set_cow(set);
 664         if (!set)
 665                 goto error;
 666
 667         for (i = 0; i < set->n; ++i) {
 668                 set->p[i] = isl_basic_set_drop_dims(set->p[i], first, n);
 669                 if (!set->p[i])
 670                         goto error;
 671         }
 672         set->dim -= n;
 673
 674         return set;
 675 error:
 676         isl_set_free(set);
 677         return NULL;
 678 }
 679
 680 /*
 681  * We don't cow, as the div is assumed to be redundant.
 682  */
 683 static struct isl_basic_map *isl_basic_map_drop_div(
 684                 struct isl_basic_map *bmap, unsigned div)
 685 {
 686         int i;
 687         unsigned pos;
 688
 689         if (!bmap)
 690                 goto error;
 691
 692         pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
 693
 694         isl_assert(bmap->ctx, div < bmap->n_div, goto error);
 695
 696         for (i = 0; i < bmap->n_eq; ++i)
 697                 constraint_drop_vars(bmap->eq[i]+pos, 1, bmap->extra-div-1);
 698
 699         for (i = 0; i < bmap->n_ineq; ++i) {
 700                 if (!isl_int_is_zero(bmap->ineq[i][pos])) {
 701                         isl_basic_map_drop_inequality(bmap, i);
 702                         --i;
 703                         continue;
 704                 }
 705                 constraint_drop_vars(bmap->ineq[i]+pos, 1, bmap->extra-div-1);
 706         }
 707
 708         for (i = 0; i < bmap->n_div; ++i)
 709                 constraint_drop_vars(bmap->div[i]+1+pos, 1, bmap->extra-div-1);
 710
 711         if (div != bmap->n_div - 1) {
 712                 int j;
 713                 isl_int *t = bmap->div[div];
 714
 715                 for (j = div; j < bmap->n_div - 1; ++j)
 716                         bmap->div[j] = bmap->div[j+1];
 717
 718                 bmap->div[bmap->n_div - 1] = t;
 719         }
 720         isl_basic_map_free_div(bmap, 1);
 721
 722         return bmap;
 723 error:
 724         isl_basic_map_free(bmap);
 725         return NULL;
 726 }
 727
 728 static void eliminate_div(struct isl_basic_map *bmap, isl_int *eq, unsigned div)
 729 {
 730         int i;
 731         unsigned pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
 732         unsigned len;
 733         len = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
 734
 735         for (i = 0; i < bmap->n_eq; ++i)
 736                 if (bmap->eq[i] != eq)
 737                         isl_seq_elim(bmap->eq[i], eq, pos, len, NULL);
 738
 739         for (i = 0; i < bmap->n_ineq; ++i)
 740                 isl_seq_elim(bmap->ineq[i], eq, pos, len, NULL);
 741
 742         /* We need to be careful about circular definitions,
 743          * so for now we just remove the definitions of other divs that
 744          * depend on this div and (possibly) recompute them later.
 745          */
 746         for (i = 0; i < bmap->n_div; ++i)
 747                 if (!isl_int_is_zero(bmap->div[i][0]) &&
 748                     !isl_int_is_zero(bmap->div[i][1 + pos]))
 749                         isl_seq_clr(bmap->div[i], 1 + len);
 750
 751         isl_basic_map_drop_div(bmap, div);
 752 }
 753
 754 struct isl_basic_map *isl_basic_map_set_to_empty(struct isl_basic_map *bmap)
 755 {
 756         int i = 0;
 757         unsigned total;
 758         if (!bmap)
 759                 goto error;
 760         total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra;
 761         isl_basic_map_free_div(bmap, bmap->n_div);
 762         isl_basic_map_free_inequality(bmap, bmap->n_ineq);
 763         if (bmap->n_eq > 0)
 764                 isl_basic_map_free_equality(bmap, bmap->n_eq-1);
 765         else {
 766                 isl_basic_map_alloc_equality(bmap);
 767                 if (i < 0)
 768                         goto error;
 769         }
 770         isl_int_set_si(bmap->eq[i][0], 1);
 771         isl_seq_clr(bmap->eq[i]+1, total);
 772         F_SET(bmap, ISL_BASIC_MAP_EMPTY);
 773         return isl_basic_map_finalize(bmap);
 774 error:
 775         isl_basic_map_free(bmap);
 776         return NULL;
 777 }
 778
 779 struct isl_basic_set *isl_basic_set_set_to_empty(struct isl_basic_set *bset)
 780 {
 781         return (struct isl_basic_set *)
 782                 isl_basic_map_set_to_empty((struct isl_basic_map *)bset);
 783 }
 784
 785 static void swap_equality(struct isl_basic_map *bmap, int a, int b)
 786 {
 787         isl_int *t = bmap->eq[a];
 788         bmap->eq[a] = bmap->eq[b];
 789         bmap->eq[b] = t;
 790 }
 791
 792 static void swap_inequality(struct isl_basic_map *bmap, int a, int b)
 793 {
 794         isl_int *t = bmap->ineq[a];
 795         bmap->ineq[a] = bmap->ineq[b];
 796         bmap->ineq[b] = t;
 797 }
 798
 799 static void swap_div(struct isl_basic_map *bmap, int a, int b)
 800 {
 801         int i;
 802         unsigned off = bmap->nparam + bmap->n_in + bmap->n_out;
 803         isl_int *t = bmap->div[a];
 804         bmap->div[a] = bmap->div[b];
 805         bmap->div[b] = t;
 806
 807         for (i = 0; i < bmap->n_eq; ++i)
 808                 isl_int_swap(bmap->eq[i][1+off+a], bmap->eq[i][1+off+b]);
 809
 810         for (i = 0; i < bmap->n_ineq; ++i)
 811                 isl_int_swap(bmap->ineq[i][1+off+a], bmap->ineq[i][1+off+b]);
 812
 813         for (i = 0; i < bmap->n_div; ++i)
 814                 isl_int_swap(bmap->div[i][1+1+off+a], bmap->div[i][1+1+off+b]);
 815 }
 816
 817 struct isl_basic_map *isl_basic_map_gauss(
 818         struct isl_basic_map *bmap, int *progress)
 819 {
 820         int k;
 821         int done;
 822         int last_var;
 823         unsigned total_var;
 824         unsigned total;
 825
 826         if (!bmap)
 827                 return NULL;
 828
 829         total_var = bmap->nparam + bmap->n_in + bmap->n_out;
 830         total = total_var + bmap->n_div;
 831
 832         last_var = total - 1;
 833         for (done = 0; done < bmap->n_eq; ++done) {
 834                 for (; last_var >= 0; --last_var) {
 835                         for (k = done; k < bmap->n_eq; ++k)
 836                                 if (!isl_int_is_zero(bmap->eq[k][1+last_var]))
 837                                         break;
 838                         if (k < bmap->n_eq)
 839                                 break;
 840                 }
 841                 if (last_var < 0)
 842                         break;
 843                 if (k != done)
 844                         swap_equality(bmap, k, done);
 845                 if (isl_int_is_neg(bmap->eq[done][1+last_var]))
 846                         isl_seq_neg(bmap->eq[done], bmap->eq[done], 1+total);
 847
 848                 for (k = 0; k < bmap->n_eq; ++k) {
 849                         if (k == done)
 850                                 continue;
 851                         if (isl_int_is_zero(bmap->eq[k][1+last_var]))
 852                                 continue;
 853                         if (progress)
 854                                 *progress = 1;
 855                         isl_seq_elim(bmap->eq[k], bmap->eq[done],
 856                                         1+last_var, 1+total, NULL);
 857                 }
 858
 859                 for (k = 0; k < bmap->n_ineq; ++k) {
 860                         if (isl_int_is_zero(bmap->ineq[k][1+last_var]))
 861                                 continue;
 862                         if (progress)
 863                                 *progress = 1;
 864                         isl_seq_elim(bmap->ineq[k], bmap->eq[done],
 865                                         1+last_var, 1+total, NULL);
 866                 }
 867
 868                 for (k = 0; k < bmap->n_div; ++k) {
 869                         if (isl_int_is_zero(bmap->div[k][0]))
 870                                 continue;
 871                         if (isl_int_is_zero(bmap->div[k][1+1+last_var]))
 872                                 continue;
 873                         if (progress)
 874                                 *progress = 1;
 875                         isl_seq_elim(bmap->div[k]+1, bmap->eq[done],
 876                                         1+last_var, 1+total, &bmap->div[k][0]);
 877                 }
 878
 879                 if (last_var >= total_var &&
 880                     isl_int_is_zero(bmap->div[last_var - total_var][0])) {
 881                         unsigned div = last_var - total_var;
 882                         isl_seq_neg(bmap->div[div]+1, bmap->eq[done], 1+total);
 883                         isl_int_set_si(bmap->div[div][1+1+last_var], 0);
 884                         isl_int_set(bmap->div[div][0],
 885                                     bmap->eq[done][1+last_var]);
 886                 }
 887         }
 888         if (done == bmap->n_eq)
 889                 return bmap;
 890         for (k = done; k < bmap->n_eq; ++k) {
 891                 if (isl_int_is_zero(bmap->eq[k][0]))
 892                         continue;
 893                 return isl_basic_map_set_to_empty(bmap);
 894         }
 895         isl_basic_map_free_equality(bmap, bmap->n_eq-done);
 896         return bmap;
 897 }
 898
 899 struct isl_basic_set *isl_basic_set_gauss(
 900         struct isl_basic_set *bset, int *progress)
 901 {
 902         return (struct isl_basic_set*)isl_basic_map_gauss(
 903                         (struct isl_basic_map *)bset, progress);
 904 }
 905
 906 static unsigned int round_up(unsigned int v)
 907 {
 908         int old_v = v;
 909
 910         while (v) {
 911                 old_v = v;
 912                 v ^= v & -v;
 913         }
 914         return old_v << 1;
 915 }
 916
 917 static int hash_index(int *index, unsigned int size, int bits,
 918                         struct isl_basic_map *bmap, int k)
 919 {
 920         int h;
 921         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
 922         u_int32_t hash = isl_seq_hash(bmap->ineq[k]+1, total, bits);
 923         for (h = hash; index[h]; h = (h+1) % size)
 924                 if (k != index[h]-1 &&
 925                     isl_seq_eq(bmap->ineq[k]+1,
 926                                bmap->ineq[index[h]-1]+1, total))
 927                         break;
 928         return h;
 929 }
 930
 931 static struct isl_basic_map *remove_duplicate_constraints(
 932         struct isl_basic_map *bmap, int *progress)
 933 {
 934         unsigned int size;
 935         int *index;
 936         int k, l, h;
 937         int bits;
 938         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
 939         isl_int sum;
 940
 941         if (bmap->n_ineq <= 1)
 942                 return bmap;
 943
 944         size = round_up(4 * (bmap->n_ineq+1) / 3 - 1);
 945         bits = ffs(size) - 1;
 946         index = isl_alloc_array(ctx, int, size);
 947         memset(index, 0, size * sizeof(int));
 948         if (!index)
 949                 return bmap;
 950
 951         index[isl_seq_hash(bmap->ineq[0]+1, total, bits)] = 1;
 952         for (k = 1; k < bmap->n_ineq; ++k) {
 953                 h = hash_index(index, size, bits, bmap, k);
 954                 if (!index[h]) {
 955                         index[h] = k+1;
 956                         continue;
 957                 }
 958                 *progress = 1;
 959                 l = index[h] - 1;
 960                 if (isl_int_lt(bmap->ineq[k][0], bmap->ineq[l][0]))
 961                         swap_inequality(bmap, k, l);
 962                 isl_basic_map_drop_inequality(bmap, k);
 963                 --k;
 964         }
 965         isl_int_init(sum);
 966         for (k = 0; k < bmap->n_ineq-1; ++k) {
 967                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 968                 h = hash_index(index, size, bits, bmap, k);
 969                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 970                 if (!index[h])
 971                         continue;
 972                 l = index[h] - 1;
 973                 isl_int_add(sum, bmap->ineq[k][0], bmap->ineq[l][0]);
 974                 if (isl_int_is_pos(sum))
 975                         continue;
 976                 if (isl_int_is_zero(sum)) {
 977                         /* We need to break out of the loop after these
 978                          * changes since the contents of the hash
 979                          * will no longer be valid.
 980                          * Plus, we probably we want to regauss first.
 981                          */
 982                         isl_basic_map_drop_inequality(bmap, l);
 983                         isl_basic_map_inequality_to_equality(bmap, k);
 984                 } else
 985                         bmap = isl_basic_map_set_to_empty(bmap);
 986                 break;
 987         }
 988         isl_int_clear(sum);
 989
 990         free(index);
 991         return bmap;
 992 }
 993
 994 static struct isl_basic_map *remove_duplicate_divs(
 995         struct isl_basic_map *bmap, int *progress)
 996 {
 997         unsigned int size;
 998         int *index;
 999         int k, l, h;
1000         int bits;
1001         struct isl_blk eq;
1002         unsigned total_var = bmap->nparam + bmap->n_in + bmap->n_out;
1003         unsigned total = total_var + bmap->n_div;
1004         struct isl_ctx *ctx;
1005
1006         if (bmap->n_div <= 1)
1007                 return bmap;
1008
1009         ctx = bmap->ctx;
1010         for (k = bmap->n_div - 1; k >= 0; --k)
1011                 if (!isl_int_is_zero(bmap->div[k][0]))
1012                         break;
1013         if (k <= 0)
1014                 return bmap;
1015
1016         size = round_up(4 * bmap->n_div / 3 - 1);
1017         bits = ffs(size) - 1;
1018         index = isl_alloc_array(ctx, int, size);
1019         memset(index, 0, size * sizeof(int));
1020         if (!index)
1021                 return bmap;
1022         eq = isl_blk_alloc(ctx, 1+total);
1023         if (isl_blk_is_error(eq))
1024                 goto out;
1025
1026         isl_seq_clr(eq.data, 1+total);
1027         index[isl_seq_hash(bmap->div[k], 2+total, bits)] = k + 1;
1028         for (--k; k >= 0; --k) {
1029                 u_int32_t hash;
1030
1031                 if (isl_int_is_zero(bmap->div[k][0]))
1032                         continue;
1033
1034                 hash = isl_seq_hash(bmap->div[k], 2+total, bits);
1035                 for (h = hash; index[h]; h = (h+1) % size)
1036                         if (isl_seq_eq(bmap->div[k],
1037                                        bmap->div[index[h]-1], 2+total))
1038                                 break;
1039                 if (index[h]) {
1040                         *progress = 1;
1041                         l = index[h] - 1;
1042                         isl_int_set_si(eq.data[1+total_var+k], -1);
1043                         isl_int_set_si(eq.data[1+total_var+l], 1);
1044                         eliminate_div(bmap, eq.data, l);
1045                         isl_int_set_si(eq.data[1+total_var+k], 0);
1046                         isl_int_set_si(eq.data[1+total_var+l], 0);
1047                 }
1048                 index[h] = k+1;
1049         }
1050
1051         isl_blk_free(ctx, eq);
1052 out:
1053         free(index);
1054         return bmap;
1055 }
1056
1057 /* Elimininate divs based on equalities
1058  */
1059 static struct isl_basic_map *eliminate_divs_eq(
1060                 struct isl_basic_map *bmap, int *progress)
1061 {
1062         int d;
1063         int i;
1064         int modified = 0;
1065         unsigned off;
1066
1067         if (!bmap)
1068                 return NULL;
1069
1070         off = 1 + bmap->nparam + bmap->n_in + bmap->n_out;
1071
1072         for (d = bmap->n_div - 1; d >= 0 ; --d) {
1073                 for (i = 0; i < bmap->n_eq; ++i) {
1074                         if (!isl_int_is_one(bmap->eq[i][off + d]) &&
1075                             !isl_int_is_negone(bmap->eq[i][off + d]))
1076                                 continue;
1077                         modified = 1;
1078                         *progress = 1;
1079                         eliminate_div(bmap, bmap->eq[i], d);
1080                         isl_basic_map_drop_equality(bmap, i);
1081                         break;
1082                 }
1083         }
1084         if (modified)
1085                 return eliminate_divs_eq(bmap, progress);
1086         return bmap;
1087 }
1088
1089 static struct isl_basic_map *normalize_constraints(struct isl_basic_map *bmap)
1090 {
1091         int i;
1092         isl_int gcd;
1093         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1094
1095         isl_int_init(gcd);
1096         for (i = bmap->n_eq - 1; i >= 0; --i) {
1097                 isl_seq_gcd(bmap->eq[i]+1, total, &gcd);
1098                 if (isl_int_is_zero(gcd)) {
1099                         if (!isl_int_is_zero(bmap->eq[i][0])) {
1100                                 bmap = isl_basic_map_set_to_empty(bmap);
1101                                 break;
1102                         }
1103                         isl_basic_map_drop_equality(bmap, i);
1104                         continue;
1105                 }
1106                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
1107                         isl_int_gcd(gcd, gcd, bmap->eq[i][0]);
1108                 if (isl_int_is_one(gcd))
1109                         continue;
1110                 if (!isl_int_is_divisible_by(bmap->eq[i][0], gcd)) {
1111                         bmap = isl_basic_map_set_to_empty(bmap);
1112                         break;
1113                 }
1114                 isl_seq_scale_down(bmap->eq[i], bmap->eq[i], gcd, 1+total);
1115         }
1116
1117         for (i = bmap->n_ineq - 1; i >= 0; --i) {
1118                 isl_seq_gcd(bmap->ineq[i]+1, total, &gcd);
1119                 if (isl_int_is_zero(gcd)) {
1120                         if (isl_int_is_neg(bmap->ineq[i][0])) {
1121                                 bmap = isl_basic_map_set_to_empty(bmap);
1122                                 break;
1123                         }
1124                         isl_basic_map_drop_inequality(bmap, i);
1125                         continue;
1126                 }
1127                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
1128                         isl_int_gcd(gcd, gcd, bmap->ineq[i][0]);
1129                 if (isl_int_is_one(gcd))
1130                         continue;
1131                 isl_int_fdiv_q(bmap->ineq[i][0], bmap->ineq[i][0], gcd);
1132                 isl_seq_scale_down(bmap->ineq[i]+1, bmap->ineq[i]+1, gcd, total);
1133         }
1134         isl_int_clear(gcd);
1135
1136         return bmap;
1137 }
1138
1139
1140 /* Eliminate the specified variables from the constraints using
1141  * Fourier-Motzkin.  The variables themselves are not removed.
1142  */
1143 struct isl_basic_map *isl_basic_map_eliminate_vars(
1144         struct isl_basic_map *bmap, int pos, unsigned n)
1145 {
1146         int d;
1147         int i, j, k;
1148         unsigned total;
1149         unsigned extra;
1150
1151         if (!bmap)
1152                 return NULL;
1153         total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1154         extra = bmap->extra - bmap->n_div;
1155
1156         bmap = isl_basic_map_cow(bmap);
1157         bmap = isl_basic_map_gauss(bmap, NULL);
1158         for (d = pos + n - 1; d >= pos; --d) {
1159                 int n_lower, n_upper;
1160                 if (!bmap)
1161                         return NULL;
1162                 for (i = 0; i < bmap->n_eq; ++i) {
1163                         if (isl_int_is_zero(bmap->eq[i][1+d]))
1164                                 continue;
1165                         isl_basic_map_drop_equality(bmap, i);
1166                         break;
1167                 }
1168                 if (i < bmap->n_eq)
1169                         continue;
1170                 n_lower = 0;
1171                 n_upper = 0;
1172                 for (i = 0; i < bmap->n_ineq; ++i) {
1173                         if (isl_int_is_pos(bmap->ineq[i][1+d]))
1174                                 n_lower++;
1175                         else if (isl_int_is_neg(bmap->ineq[i][1+d]))
1176                                 n_upper++;
1177                 }
1178                 bmap = isl_basic_map_extend(bmap,
1179                                 bmap->nparam, bmap->n_in, bmap->n_out, 0,
1180                                 0, n_lower * n_upper);
1181                 for (i = bmap->n_ineq - 1; i >= 0; --i) {
1182                         int last;
1183                         if (isl_int_is_zero(bmap->ineq[i][1+d]))
1184                                 continue;
1185                         last = -1;
1186                         for (j = 0; j < i; ++j) {
1187                                 if (isl_int_is_zero(bmap->ineq[j][1+d]))
1188                                         continue;
1189                                 last = j;
1190                                 if (isl_int_sgn(bmap->ineq[i][1+d]) ==
1191                                     isl_int_sgn(bmap->ineq[j][1+d]))
1192                                         continue;
1193                                 k = isl_basic_map_alloc_inequality(bmap);
1194                                 if (k < 0)
1195                                         goto error;
1196                                 isl_seq_cpy(bmap->ineq[k], bmap->ineq[i],
1197                                                 1+total);
1198                                 isl_seq_clr(bmap->ineq[k]+1+total, extra);
1199                                 isl_seq_elim(bmap->ineq[k], bmap->ineq[j],
1200                                                 1+d, 1+total, NULL);
1201                         }
1202                         isl_basic_map_drop_inequality(bmap, i);
1203                         i = last + 1;
1204                 }
1205                 if (n_lower > 0 && n_upper > 0) {
1206                         bmap = normalize_constraints(bmap);
1207                         bmap = isl_basic_map_gauss(bmap, NULL);
1208                         if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
1209                                 break;
1210                 }
1211         }
1212         return bmap;
1213 error:
1214         isl_basic_map_free(bmap);
1215         return NULL;
1216 }
1217
1218 struct isl_basic_set *isl_basic_set_eliminate_vars(
1219         struct isl_basic_set *bset, unsigned pos, unsigned n)
1220 {
1221         return (struct isl_basic_set *)isl_basic_map_eliminate_vars(
1222                         (struct isl_basic_map *)bset, pos, n);
1223 }
1224
1225 /* Project out n dimensions starting at first using Fourier-Motzkin */
1226 struct isl_set *isl_set_remove_dims(struct isl_set *set,
1227         unsigned first, unsigned n)
1228 {
1229         int i;
1230
1231         if (n == 0)
1232                 return set;
1233
1234         set = isl_set_cow(set);
1235         if (!set)
1236                 return NULL;
1237         isl_assert(set->ctx, first+n <= set->dim, goto error);
1238
1239         for (i = 0; i < set->n; ++i) {
1240                 set->p[i] = isl_basic_set_eliminate_vars(set->p[i],
1241                                                         set->nparam + first, n);
1242                 if (!set->p[i])
1243                         goto error;
1244         }
1245         set = isl_set_drop_dims(set, first, n);
1246         return set;
1247 error:
1248         isl_set_free(set);
1249         return NULL;
1250 }
1251
1252 /* Project out n dimensions starting at first using Fourier-Motzkin */
1253 struct isl_basic_set *isl_basic_set_remove_dims(struct isl_basic_set *bset,
1254         unsigned first, unsigned n)
1255 {
1256         bset = isl_basic_set_eliminate_vars(bset, bset->nparam + first, n);
1257         bset = isl_basic_set_drop_dims(bset, first, n);
1258         return bset;
1259 }
1260
1261 /* Elimininate divs based on inequalities
1262  */
1263 static struct isl_basic_map *eliminate_divs_ineq(
1264                 struct isl_basic_map *bmap, int *progress)
1265 {
1266         int d;
1267         int i;
1268         unsigned off;
1269         struct isl_ctx *ctx;
1270
1271         if (!bmap)
1272                 return NULL;
1273
1274         ctx = bmap->ctx;
1275         off = 1 + bmap->nparam + bmap->n_in + bmap->n_out;
1276
1277         for (d = bmap->n_div - 1; d >= 0 ; --d) {
1278                 for (i = 0; i < bmap->n_eq; ++i)
1279                         if (!isl_int_is_zero(bmap->eq[i][off + d]))
1280                                 break;
1281                 if (i < bmap->n_eq)
1282                         continue;
1283                 for (i = 0; i < bmap->n_ineq; ++i)
1284                         if (isl_int_abs_gt(bmap->ineq[i][off + d], ctx->one))
1285                                 break;
1286                 if (i < bmap->n_ineq)
1287                         continue;
1288                 *progress = 1;
1289                 bmap = isl_basic_map_eliminate_vars(bmap, (off-1)+d, 1);
1290                 if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
1291                         break;
1292                 bmap = isl_basic_map_drop_div(bmap, d);
1293                 if (!bmap)
1294                         break;
1295         }
1296         return bmap;
1297 }
1298
1299 struct isl_basic_map *isl_basic_map_simplify(struct isl_basic_map *bmap)
1300 {
1301         int progress = 1;
1302         if (!bmap)
1303                 return NULL;
1304         while (progress) {
1305                 progress = 0;
1306                 bmap = normalize_constraints(bmap);
1307                 bmap = eliminate_divs_eq(bmap, &progress);
1308                 bmap = eliminate_divs_ineq(bmap, &progress);
1309                 bmap = isl_basic_map_gauss(bmap, &progress);
1310                 bmap = remove_duplicate_divs(bmap, &progress);
1311                 bmap = remove_duplicate_constraints(bmap, &progress);
1312         }
1313         return bmap;
1314 }
1315
1316 struct isl_basic_set *isl_basic_set_simplify(struct isl_basic_set *bset)
1317 {
1318         return (struct isl_basic_set *)
1319                 isl_basic_map_simplify((struct isl_basic_map *)bset);
1320 }
1321
1322 static void dump_term(struct isl_basic_map *bmap,
1323                         isl_int c, int pos, FILE *out)
1324 {
1325         unsigned in = bmap->n_in;
1326         unsigned dim = bmap->n_in + bmap->n_out;
1327         if (!pos)
1328                 isl_int_print(out, c);
1329         else {
1330                 if (!isl_int_is_one(c))
1331                         isl_int_print(out, c);
1332                 if (pos < 1 + bmap->nparam)
1333                         fprintf(out, "p%d", pos - 1);
1334                 else if (pos < 1 + bmap->nparam + in)
1335                         fprintf(out, "i%d", pos - 1 - bmap->nparam);
1336                 else if (pos < 1 + bmap->nparam + dim)
1337                         fprintf(out, "o%d", pos - 1 - bmap->nparam - in);
1338                 else
1339                         fprintf(out, "e%d", pos - 1 - bmap->nparam - dim);
1340         }
1341 }
1342
1343 static void dump_constraint_sign(struct isl_basic_map *bmap, isl_int *c,
1344                                 int sign, FILE *out)
1345 {
1346         int i;
1347         int first;
1348         unsigned len = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1349         isl_int v;
1350
1351         isl_int_init(v);
1352         for (i = 0, first = 1; i < len; ++i) {
1353                 if (isl_int_sgn(c[i]) * sign <= 0)
1354                         continue;
1355                 if (!first)
1356                         fprintf(out, " + ");
1357                 first = 0;
1358                 isl_int_abs(v, c[i]);
1359                 dump_term(bmap, v, i, out);
1360         }
1361         isl_int_clear(v);
1362         if (first)
1363                 fprintf(out, "0");
1364 }
1365
1366 static void dump_constraint(struct isl_basic_map *bmap, isl_int *c,
1367                                 const char *op, FILE *out, int indent)
1368 {
1369         int i;
1370
1371         fprintf(out, "%*s", indent, "");
1372
1373         dump_constraint_sign(bmap, c, 1, out);
1374         fprintf(out, " %s ", op);
1375         dump_constraint_sign(bmap, c, -1, out);
1376
1377         fprintf(out, "\n");
1378
1379         for (i = bmap->n_div; i < bmap->extra; ++i) {
1380                 if (isl_int_is_zero(c[1+bmap->nparam+bmap->n_in+bmap->n_out+i]))
1381                         continue;
1382                 fprintf(out, "%*s", indent, "");
1383                 fprintf(out, "ERROR: unused div coefficient not zero\n");
1384         }
1385 }
1386
1387 static void dump_constraints(struct isl_basic_map *bmap,
1388                                 isl_int **c, unsigned n,
1389                                 const char *op, FILE *out, int indent)
1390 {
1391         int i;
1392
1393         for (i = 0; i < n; ++i)
1394                 dump_constraint(bmap, c[i], op, out, indent);
1395 }
1396
1397 static void dump_affine(struct isl_basic_map *bmap, isl_int *exp, FILE *out)
1398 {
1399         int j;
1400         int first = 1;
1401         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1402
1403         for (j = 0; j < 1 + total; ++j) {
1404                 if (isl_int_is_zero(exp[j]))
1405                         continue;
1406                 if (!first && isl_int_is_pos(exp[j]))
1407                         fprintf(out, "+");
1408                 dump_term(bmap, exp[j], j, out);
1409                 first = 0;
1410         }
1411 }
1412
1413 static void dump(struct isl_basic_map *bmap, FILE *out, int indent)
1414 {
1415         int i;
1416
1417         dump_constraints(bmap, bmap->eq, bmap->n_eq, "=", out, indent);
1418         dump_constraints(bmap, bmap->ineq, bmap->n_ineq, ">=", out, indent);
1419
1420         for (i = 0; i < bmap->n_div; ++i) {
1421                 fprintf(out, "%*s", indent, "");
1422                 fprintf(out, "e%d = [(", i);
1423                 dump_affine(bmap, bmap->div[i]+1, out);
1424                 fprintf(out, ")/");
1425                 isl_int_print(out, bmap->div[i][0]);
1426                 fprintf(out, "]\n");
1427         }
1428 }
1429
1430 void isl_basic_set_dump(struct isl_basic_set *bset, FILE *out, int indent)
1431 {
1432         if (!bset) {
1433                 fprintf(out, "null basic set\n");
1434                 return;
1435         }
1436
1437         fprintf(out, "%*s", indent, "");
1438         fprintf(out, "ref: %d, nparam: %d, dim: %d, extra: %d\n",
1439                         bset->ref, bset->nparam, bset->dim, bset->extra);
1440         dump((struct isl_basic_map *)bset, out, indent);
1441 }
1442
1443 void isl_basic_map_dump(struct isl_basic_map *bmap, FILE *out, int indent)
1444 {
1445         if (!bmap) {
1446                 fprintf(out, "null basic map\n");
1447                 return;
1448         }
1449
1450         fprintf(out, "%*s", indent, "");
1451         fprintf(out, "ref: %d, nparam: %d, in: %d, out: %d, extra: %d, flags: %x\n",
1452                 bmap->ref,
1453                 bmap->nparam, bmap->n_in, bmap->n_out, bmap->extra, bmap->flags);
1454         dump(bmap, out, indent);
1455 }
1456
1457 int isl_inequality_negate(struct isl_basic_map *bmap, unsigned pos)
1458 {
1459         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1460         if (!bmap)
1461                 return -1;
1462         isl_assert(bmap->ctx, pos < bmap->n_ineq, return -1);
1463         isl_seq_neg(bmap->ineq[pos], bmap->ineq[pos], 1 + total);
1464         isl_int_sub_ui(bmap->ineq[pos][0], bmap->ineq[pos][0], 1);
1465         return 0;
1466 }
1467
1468 struct isl_set *isl_set_alloc(struct isl_ctx *ctx,
1469                 unsigned nparam, unsigned dim, int n, unsigned flags)
1470 {
1471         struct isl_set *set;
1472
1473         isl_assert(ctx, n >= 0, return NULL);
1474         set = isl_alloc(ctx, struct isl_set,
1475                         sizeof(struct isl_set) +
1476                         n * sizeof(struct isl_basic_set *));
1477         if (!set)
1478                 return NULL;
1479
1480         set->ctx = ctx;
1481         isl_ctx_ref(ctx);
1482         set->ref = 1;
1483         set->size = n;
1484         set->n = 0;
1485         set->nparam = nparam;
1486         set->zero = 0;
1487         set->dim = dim;
1488         set->flags = flags;
1489         return set;
1490 }
1491
1492 struct isl_set *isl_set_dup(struct isl_set *set)
1493 {
1494         int i;
1495         struct isl_set *dup;
1496
1497         if (!set)
1498                 return NULL;
1499
1500         dup = isl_set_alloc(set->ctx, set->nparam, set->dim, set->n, set->flags);
1501         if (!dup)
1502                 return NULL;
1503         for (i = 0; i < set->n; ++i)
1504                 dup = isl_set_add(dup,
1505                                   isl_basic_set_dup(set->p[i]));
1506         return dup;
1507 }
1508
1509 struct isl_set *isl_set_from_basic_set(struct isl_basic_set *bset)
1510 {
1511         struct isl_set *set;
1512
1513         if (!bset)
1514                 return NULL;
1515
1516         set = isl_set_alloc(bset->ctx, bset->nparam, bset->dim, 1, ISL_MAP_DISJOINT);
1517         if (!set) {
1518                 isl_basic_set_free(bset);
1519                 return NULL;
1520         }
1521         return isl_set_add(set, bset);
1522 }
1523
1524 struct isl_map *isl_map_from_basic_map(struct isl_basic_map *bmap)
1525 {
1526         struct isl_map *map;
1527
1528         if (!bmap)
1529                 return NULL;
1530
1531         map = isl_map_alloc(bmap->ctx, bmap->nparam, bmap->n_in, bmap->n_out, 1,
1532                                 ISL_MAP_DISJOINT);
1533         if (!map) {
1534                 isl_basic_map_free(bmap);
1535                 return NULL;
1536         }
1537         return isl_map_add(map, bmap);
1538 }
1539
1540 struct isl_set *isl_set_add(struct isl_set *set, struct isl_basic_set *bset)
1541 {
1542         if (!bset || !set)
1543                 goto error;
1544         isl_assert(set->ctx, set->nparam == bset->nparam, goto error);
1545         isl_assert(set->ctx, set->dim == bset->dim, goto error);
1546         isl_assert(set->ctx, set->n < set->size, goto error);
1547         set->p[set->n] = bset;
1548         set->n++;
1549         return set;
1550 error:
1551         if (set)
1552                 isl_set_free(set);
1553         if (bset)
1554                 isl_basic_set_free(bset);
1555         return NULL;
1556 }
1557
1558 void isl_set_free(struct isl_set *set)
1559 {
1560         int i;
1561
1562         if (!set)
1563                 return;
1564
1565         if (--set->ref > 0)
1566                 return;
1567
1568         isl_ctx_deref(set->ctx);
1569         for (i = 0; i < set->n; ++i)
1570                 isl_basic_set_free(set->p[i]);
1571         free(set);
1572 }
1573
1574 void isl_set_dump(struct isl_set *set, FILE *out, int indent)
1575 {
1576         int i;
1577
1578         if (!set) {
1579                 fprintf(out, "null set\n");
1580                 return;
1581         }
1582
1583         fprintf(out, "%*s", indent, "");
1584         fprintf(out, "ref: %d, n: %d, nparam: %d, dim: %d, flags: %x\n",
1585                         set->ref, set->n, set->nparam, set->dim, set->flags);
1586         for (i = 0; i < set->n; ++i) {
1587                 fprintf(out, "%*s", indent, "");
1588                 fprintf(out, "basic set %d:\n", i);
1589                 isl_basic_set_dump(set->p[i], out, indent+4);
1590         }
1591 }
1592
1593 void isl_map_dump(struct isl_map *map, FILE *out, int indent)
1594 {
1595         int i;
1596
1597         if (!map) {
1598                 fprintf(out, "null map\n");
1599                 return;
1600         }
1601
1602         fprintf(out, "%*s", indent, "");
1603         fprintf(out, "ref: %d, n: %d, nparam: %d, in: %d, out: %d, flags: %x\n",
1604                         map->ref, map->n, map->nparam, map->n_in, map->n_out,
1605                         map->flags);
1606         for (i = 0; i < map->n; ++i) {
1607                 fprintf(out, "%*s", indent, "");
1608                 fprintf(out, "basic map %d:\n", i);
1609                 isl_basic_map_dump(map->p[i], out, indent+4);
1610         }
1611 }
1612
1613 struct isl_basic_map *isl_basic_map_intersect_domain(
1614                 struct isl_basic_map *bmap, struct isl_basic_set *bset)
1615 {
1616         struct isl_basic_map *bmap_domain;
1617
1618         if (!bmap || !bset)
1619                 goto error;
1620
1621         isl_assert(bset->ctx, bset->dim == bmap->n_in, goto error);
1622         isl_assert(bset->ctx, bset->nparam == bmap->nparam, goto error);
1623
1624         bmap = isl_basic_map_extend(bmap,
1625                         bset->nparam, bmap->n_in, bmap->n_out,
1626                         bset->n_div, bset->n_eq, bset->n_ineq);
1627         if (!bmap)
1628                 goto error;
1629         bmap_domain = isl_basic_map_from_basic_set(bset,
1630                                                 bset->dim, 0);
1631         bmap = add_constraints(bmap, bmap_domain, 0, 0);
1632
1633         bmap = isl_basic_map_simplify(bmap);
1634         return isl_basic_map_finalize(bmap);
1635 error:
1636         isl_basic_map_free(bmap);
1637         isl_basic_set_free(bset);
1638         return NULL;
1639 }
1640
1641 struct isl_basic_map *isl_basic_map_intersect_range(
1642                 struct isl_basic_map *bmap, struct isl_basic_set *bset)
1643 {
1644         struct isl_basic_map *bmap_range;
1645
1646         if (!bmap || !bset)
1647                 goto error;
1648
1649         isl_assert(bset->ctx, bset->dim == bmap->n_out, goto error);
1650         isl_assert(bset->ctx, bset->nparam == bmap->nparam, goto error);
1651
1652         bmap = isl_basic_map_extend(bmap,
1653                         bset->nparam, bmap->n_in, bmap->n_out,
1654                         bset->n_div, bset->n_eq, bset->n_ineq);
1655         if (!bmap)
1656                 goto error;
1657         bmap_range = isl_basic_map_from_basic_set(bset,
1658                                                 0, bset->dim);
1659         bmap = add_constraints(bmap, bmap_range, 0, 0);
1660
1661         bmap = isl_basic_map_simplify(bmap);
1662         return isl_basic_map_finalize(bmap);
1663 error:
1664         isl_basic_map_free(bmap);
1665         isl_basic_set_free(bset);
1666         return NULL;
1667 }
1668
1669 struct isl_basic_map *isl_basic_map_intersect(
1670                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1671 {
1672         if (!bmap1 || !bmap2)
1673                 goto error;
1674
1675         isl_assert(bmap1->ctx, bmap1->nparam == bmap2->nparam, goto error);
1676         isl_assert(bmap1->ctx, bmap1->n_in == bmap2->n_in, goto error);
1677         isl_assert(bmap1->ctx, bmap1->n_out == bmap2->n_out, goto error);
1678
1679         bmap1 = isl_basic_map_extend(bmap1,
1680                         bmap1->nparam, bmap1->n_in, bmap1->n_out,
1681                         bmap2->n_div, bmap2->n_eq, bmap2->n_ineq);
1682         if (!bmap1)
1683                 goto error;
1684         bmap1 = add_constraints(bmap1, bmap2, 0, 0);
1685
1686         bmap1 = isl_basic_map_simplify(bmap1);
1687         return isl_basic_map_finalize(bmap1);
1688 error:
1689         isl_basic_map_free(bmap1);
1690         isl_basic_map_free(bmap2);
1691         return NULL;
1692 }
1693
1694 struct isl_basic_set *isl_basic_set_intersect(
1695                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
1696 {
1697         return (struct isl_basic_set *)
1698                 isl_basic_map_intersect(
1699                         (struct isl_basic_map *)bset1,
1700                         (struct isl_basic_map *)bset2);
1701 }
1702
1703 struct isl_map *isl_map_intersect(struct isl_map *map1, struct isl_map *map2)
1704 {
1705         unsigned flags = 0;
1706         struct isl_map *result;
1707         int i, j;
1708
1709         if (!map1 || !map2)
1710                 goto error;
1711
1712         if (F_ISSET(map1, ISL_MAP_DISJOINT) &&
1713             F_ISSET(map2, ISL_MAP_DISJOINT))
1714                 FL_SET(flags, ISL_MAP_DISJOINT);
1715
1716         result = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map1->n_out,
1717                                 map1->n * map2->n, flags);
1718         if (!result)
1719                 goto error;
1720         for (i = 0; i < map1->n; ++i)
1721                 for (j = 0; j < map2->n; ++j) {
1722                         struct isl_basic_map *part;
1723                         part = isl_basic_map_intersect(
1724                                     isl_basic_map_copy(map1->p[i]),
1725                                     isl_basic_map_copy(map2->p[j]));
1726                         if (isl_basic_map_is_empty(part))
1727                                 isl_basic_map_free(part);
1728                         else
1729                                 result = isl_map_add(result, part);
1730                         if (!result)
1731                                 goto error;
1732                 }
1733         isl_map_free(map1);
1734         isl_map_free(map2);
1735         return result;
1736 error:
1737         isl_map_free(map1);
1738         isl_map_free(map2);
1739         return NULL;
1740 }
1741
1742 struct isl_set *isl_set_intersect(struct isl_set *set1, struct isl_set *set2)
1743 {
1744         return (struct isl_set *)
1745                 isl_map_intersect((struct isl_map *)set1,
1746                                   (struct isl_map *)set2);
1747 }
1748
1749 struct isl_basic_map *isl_basic_map_reverse(struct isl_basic_map *bmap)
1750 {
1751         struct isl_basic_set *bset;
1752         unsigned in;
1753
1754         if (!bmap)
1755                 return NULL;
1756         bmap = isl_basic_map_cow(bmap);
1757         if (!bmap)
1758                 return NULL;
1759         in = bmap->n_in;
1760         bset = isl_basic_set_from_basic_map(bmap);
1761         bset = isl_basic_set_swap_vars(bset, in);
1762         return isl_basic_map_from_basic_set(bset, bset->dim-in, in);
1763 }
1764
1765 /* Turn final n dimensions into existentially quantified variables.
1766  */
1767 struct isl_basic_set *isl_basic_set_project_out(
1768                 struct isl_basic_set *bset, unsigned n, unsigned flags)
1769 {
1770         int i;
1771         size_t row_size;
1772         isl_int **new_div;
1773         isl_int *old;
1774
1775         if (!bset)
1776                 return NULL;
1777
1778         isl_assert(bset->ctx, n <= bset->dim, goto error);
1779
1780         if (n == 0)
1781                 return bset;
1782
1783         bset = isl_basic_set_cow(bset);
1784
1785         row_size = 1 + bset->nparam + bset->dim + bset->extra;
1786         old = bset->block2.data;
1787         bset->block2 = isl_blk_extend(bset->ctx, bset->block2,
1788                                         (bset->extra + n) * (1 + row_size));
1789         if (!bset->block2.data)
1790                 goto error;
1791         new_div = isl_alloc_array(ctx, isl_int *, bset->extra + n);
1792         if (!new_div)
1793                 goto error;
1794         for (i = 0; i < n; ++i) {
1795                 new_div[i] = bset->block2.data +
1796                                 (bset->extra + i) * (1 + row_size);
1797                 isl_seq_clr(new_div[i], 1 + row_size);
1798         }
1799         for (i = 0; i < bset->extra; ++i)
1800                 new_div[n + i] = bset->block2.data + (bset->div[i] - old);
1801         free(bset->div);
1802         bset->div = new_div;
1803         bset->n_div += n;
1804         bset->extra += n;
1805         bset->dim -= n;
1806         bset = isl_basic_set_simplify(bset);
1807         return isl_basic_set_finalize(bset);
1808 error:
1809         isl_basic_set_free(bset);
1810         return NULL;
1811 }
1812
1813 struct isl_basic_map *isl_basic_map_apply_range(
1814                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1815 {
1816         struct isl_basic_set *bset;
1817         unsigned n_in, n_out;
1818
1819         if (!bmap1 || !bmap2)
1820                 goto error;
1821
1822         isl_assert(bmap->ctx, bmap1->n_out == bmap2->n_in, goto error);
1823         isl_assert(bmap->ctx, bmap1->nparam == bmap2->nparam, goto error);
1824
1825         n_in = bmap1->n_in;
1826         n_out = bmap2->n_out;
1827
1828         bmap2 = isl_basic_map_reverse(bmap2);
1829         if (!bmap2)
1830                 goto error;
1831         bmap1 = isl_basic_map_extend(bmap1, bmap1->nparam,
1832                         bmap1->n_in + bmap2->n_in, bmap1->n_out,
1833                         bmap2->extra, bmap2->n_eq, bmap2->n_ineq);
1834         if (!bmap1)
1835                 goto error;
1836         bmap1 = add_constraints(bmap1, bmap2, bmap1->n_in - bmap2->n_in, 0);
1837         bmap1 = isl_basic_map_simplify(bmap1);
1838         bset = isl_basic_set_from_basic_map(bmap1);
1839         bset = isl_basic_set_project_out(bset,
1840                                                 bset->dim - (n_in + n_out), 0);
1841         return isl_basic_map_from_basic_set(bset, n_in, n_out);
1842 error:
1843         isl_basic_map_free(bmap1);
1844         isl_basic_map_free(bmap2);
1845         return NULL;
1846 }
1847
1848 struct isl_basic_set *isl_basic_set_apply(
1849                 struct isl_basic_set *bset, struct isl_basic_map *bmap)
1850 {
1851         if (!bset || !bmap)
1852                 goto error;
1853
1854         isl_assert(bset->ctx, bset->dim == bmap->n_in, goto error);
1855
1856         return (struct isl_basic_set *)
1857                 isl_basic_map_apply_range((struct isl_basic_map *)bset, bmap);
1858 error:
1859         isl_basic_set_free(bset);
1860         isl_basic_map_free(bmap);
1861         return NULL;
1862 }
1863
1864 struct isl_basic_map *isl_basic_map_apply_domain(
1865                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1866 {
1867         if (!bmap1 || !bmap2)
1868                 goto error;
1869
1870         isl_assert(ctx, bmap1->n_in == bmap2->n_in, goto error);
1871         isl_assert(ctx, bmap1->nparam == bmap2->nparam, goto error);
1872
1873         bmap1 = isl_basic_map_reverse(bmap1);
1874         bmap1 = isl_basic_map_apply_range(bmap1, bmap2);
1875         return isl_basic_map_reverse(bmap1);
1876 error:
1877         isl_basic_map_free(bmap1);
1878         isl_basic_map_free(bmap2);
1879         return NULL;
1880 }
1881
1882 static struct isl_basic_map *var_equal(struct isl_ctx *ctx,
1883                 struct isl_basic_map *bmap, unsigned pos)
1884 {
1885         int i;
1886         i = isl_basic_map_alloc_equality(bmap);
1887         if (i < 0)
1888                 goto error;
1889         isl_seq_clr(bmap->eq[i],
1890                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1891         isl_int_set_si(bmap->eq[i][1+bmap->nparam+pos], -1);
1892         isl_int_set_si(bmap->eq[i][1+bmap->nparam+bmap->n_in+pos], 1);
1893         return isl_basic_map_finalize(bmap);
1894 error:
1895         isl_basic_map_free(bmap);
1896         return NULL;
1897 }
1898
1899 static struct isl_basic_map *var_more(struct isl_ctx *ctx,
1900                 struct isl_basic_map *bmap, unsigned pos)
1901 {
1902         int i;
1903         i = isl_basic_map_alloc_inequality(bmap);
1904         if (i < 0)
1905                 goto error;
1906         isl_seq_clr(bmap->ineq[i],
1907                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1908         isl_int_set_si(bmap->ineq[i][0], -1);
1909         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+pos], -1);
1910         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+bmap->n_in+pos], 1);
1911         return isl_basic_map_finalize(bmap);
1912 error:
1913         isl_basic_map_free(bmap);
1914         return NULL;
1915 }
1916
1917 static struct isl_basic_map *var_less(struct isl_ctx *ctx,
1918                 struct isl_basic_map *bmap, unsigned pos)
1919 {
1920         int i;
1921         i = isl_basic_map_alloc_inequality(bmap);
1922         if (i < 0)
1923                 goto error;
1924         isl_seq_clr(bmap->ineq[i],
1925                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1926         isl_int_set_si(bmap->ineq[i][0], -1);
1927         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+pos], 1);
1928         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+bmap->n_in+pos], -1);
1929         return isl_basic_map_finalize(bmap);
1930 error:
1931         isl_basic_map_free(bmap);
1932         return NULL;
1933 }
1934
1935 struct isl_basic_map *isl_basic_map_equal(struct isl_ctx *ctx,
1936                 unsigned nparam, unsigned in, unsigned out, unsigned n_equal)
1937 {
1938         int i;
1939         struct isl_basic_map *bmap;
1940         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, n_equal, 0);
1941         if (!bmap)
1942                 return NULL;
1943         for (i = 0; i < n_equal && bmap; ++i)
1944                 bmap = var_equal(ctx, bmap, i);
1945         return isl_basic_map_finalize(bmap);
1946 }
1947
1948 struct isl_basic_map *isl_basic_map_less_at(struct isl_ctx *ctx,
1949                 unsigned nparam, unsigned in, unsigned out, unsigned pos)
1950 {
1951         int i;
1952         struct isl_basic_map *bmap;
1953         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, pos, 1);
1954         if (!bmap)
1955                 return NULL;
1956         for (i = 0; i < pos && bmap; ++i)
1957                 bmap = var_equal(ctx, bmap, i);
1958         if (bmap)
1959                 bmap = var_less(ctx, bmap, pos);
1960         return isl_basic_map_finalize(bmap);
1961 }
1962
1963 struct isl_basic_map *isl_basic_map_more_at(struct isl_ctx *ctx,
1964                 unsigned nparam, unsigned in, unsigned out, unsigned pos)
1965 {
1966         int i;
1967         struct isl_basic_map *bmap;
1968         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, pos, 1);
1969         if (!bmap)
1970                 return NULL;
1971         for (i = 0; i < pos && bmap; ++i)
1972                 bmap = var_equal(ctx, bmap, i);
1973         if (bmap)
1974                 bmap = var_more(ctx, bmap, pos);
1975         return isl_basic_map_finalize(bmap);
1976 }
1977
1978 struct isl_basic_map *isl_basic_map_from_basic_set(
1979                 struct isl_basic_set *bset, unsigned n_in, unsigned n_out)
1980 {
1981         struct isl_basic_map *bmap;
1982
1983         bset = isl_basic_set_cow(bset);
1984         if (!bset)
1985                 return NULL;
1986
1987         isl_assert(ctx, bset->dim == n_in + n_out, goto error);
1988         bmap = (struct isl_basic_map *) bset;
1989         bmap->n_in = n_in;
1990         bmap->n_out = n_out;
1991         return isl_basic_map_finalize(bmap);
1992 error:
1993         isl_basic_set_free(bset);
1994         return NULL;
1995 }
1996
1997 struct isl_basic_set *isl_basic_set_from_basic_map(struct isl_basic_map *bmap)
1998 {
1999         if (!bmap)
2000                 goto error;
2001         if (bmap->n_in == 0)
2002                 return (struct isl_basic_set *)bmap;
2003         bmap = isl_basic_map_cow(bmap);
2004         if (!bmap)
2005                 goto error;
2006         bmap->n_out += bmap->n_in;
2007         bmap->n_in = 0;
2008         bmap = isl_basic_map_finalize(bmap);
2009         return (struct isl_basic_set *)bmap;
2010 error:
2011         return NULL;
2012 }
2013
2014 /* For a div d = floor(f/m), add the constraints
2015  *
2016  *              f - m d >= 0
2017  *              -(f-(n-1)) + m d >= 0
2018  *
2019  * Note that the second constraint is the negation of
2020  *
2021  *              f - m d >= n
2022  */
2023 static int add_div_constraints(struct isl_basic_map *bmap, unsigned div)
2024 {
2025         int i, j;
2026         unsigned div_pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
2027         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra;
2028
2029         i = isl_basic_map_alloc_inequality(bmap);
2030         if (i < 0)
2031                 return -1;
2032         isl_seq_cpy(bmap->ineq[i], bmap->div[div]+1, 1+total);
2033         isl_int_neg(bmap->ineq[i][div_pos], bmap->div[div][0]);
2034
2035         j = isl_basic_map_alloc_inequality(bmap);
2036         if (j < 0)
2037                 return -1;
2038         isl_seq_neg(bmap->ineq[j], bmap->ineq[i], 1 + total);
2039         isl_int_add(bmap->ineq[j][0], bmap->ineq[j][0], bmap->ineq[j][div_pos]);
2040         isl_int_sub_ui(bmap->ineq[j][0], bmap->ineq[j][0], 1);
2041         return j;
2042 }
2043
2044 struct isl_basic_set *isl_basic_map_underlying_set(
2045                 struct isl_basic_map *bmap)
2046 {
2047         if (!bmap)
2048                 goto error;
2049         if (bmap->nparam == 0 && bmap->n_in == 0 && bmap->n_div == 0)
2050                 return (struct isl_basic_set *)bmap;
2051         bmap = isl_basic_map_cow(bmap);
2052         if (!bmap)
2053                 goto error;
2054         bmap->n_out += bmap->nparam + bmap->n_in + bmap->n_div;
2055         bmap->nparam = 0;
2056         bmap->n_in = 0;
2057         bmap->extra -= bmap->n_div;
2058         bmap->n_div = 0;
2059         bmap = isl_basic_map_finalize(bmap);
2060         return (struct isl_basic_set *)bmap;
2061 error:
2062         return NULL;
2063 }
2064
2065 struct isl_basic_map *isl_basic_map_overlying_set(
2066         struct isl_basic_set *bset, struct isl_basic_map *like)
2067 {
2068         struct isl_basic_map *bmap;
2069         struct isl_ctx *ctx;
2070         unsigned total;
2071         int i, k;
2072
2073         if (!bset || !like)
2074                 goto error;
2075         ctx = bset->ctx;
2076         isl_assert(ctx, bset->dim ==
2077                         like->nparam + like->n_in + like->n_out + like->n_div,
2078                         goto error);
2079         if (like->nparam == 0 && like->n_in == 0 && like->n_div == 0) {
2080                 isl_basic_map_free(like);
2081                 return (struct isl_basic_map *)bset;
2082         }
2083         bset = isl_basic_set_cow(bset);
2084         if (!bset)
2085                 goto error;
2086         total = bset->dim + bset->extra;
2087         bmap = (struct isl_basic_map *)bset;
2088         bmap->nparam = like->nparam;
2089         bmap->n_in = like->n_in;
2090         bmap->n_out = like->n_out;
2091         bmap->extra += like->n_div;
2092         if (bmap->extra) {
2093                 unsigned ltotal;
2094                 ltotal = total - bmap->extra + like->extra;
2095                 if (ltotal > total)
2096                         ltotal = total;
2097                 bmap->block2 = isl_blk_extend(ctx, bmap->block2,
2098                                         bmap->extra * (1 + 1 + total));
2099                 if (isl_blk_is_error(bmap->block2))
2100                         goto error;
2101                 bmap->div = isl_realloc_array(ctx, bmap->div, isl_int *,
2102                                                 bmap->extra);
2103                 if (!bmap->div)
2104                         goto error;
2105                 bmap = isl_basic_map_extend(bmap, bmap->nparam,
2106                         bmap->n_in, bmap->n_out, 0, 0, 2 * like->n_div);
2107                 for (i = 0; i < like->n_div; ++i) {
2108                         k = isl_basic_map_alloc_div(bmap);
2109                         if (k < 0)
2110                                 goto error;
2111                         isl_seq_cpy(bmap->div[k], like->div[i], 1 + 1 + ltotal);
2112                         isl_seq_clr(bmap->div[k]+1+1+ltotal, total - ltotal);
2113                         if (add_div_constraints(bmap, k) < 0)
2114                                 goto error;
2115                 }
2116         }
2117         isl_basic_map_free(like);
2118         bmap = isl_basic_map_finalize(bmap);
2119         return bmap;
2120 error:
2121         isl_basic_map_free(like);
2122         isl_basic_set_free(bset);
2123         return NULL;
2124 }
2125
2126 struct isl_basic_set *isl_basic_set_from_underlying_set(
2127         struct isl_basic_set *bset, struct isl_basic_set *like)
2128 {
2129         return (struct isl_basic_set *)
2130                 isl_basic_map_overlying_set(bset, (struct isl_basic_map *)like);
2131 }
2132
2133 struct isl_set *isl_set_from_underlying_set(
2134         struct isl_set *set, struct isl_basic_set *like)
2135 {
2136         int i;
2137
2138         if (!set || !like)
2139                 goto error;
2140         isl_assert(set->ctx, set->dim == like->nparam + like->dim + like->n_div,
2141                     goto error);
2142         if (like->nparam == 0 && like->n_div == 0) {
2143                 isl_basic_set_free(like);
2144                 return set;
2145         }
2146         set = isl_set_cow(set);
2147         if (!set)
2148                 goto error;
2149         for (i = 0; i < set->n; ++i) {
2150                 set->p[i] = isl_basic_set_from_underlying_set(set->p[i],
2151                                                       isl_basic_set_copy(like));
2152                 if (!set->p[i])
2153                         goto error;
2154         }
2155         set->nparam = like->nparam;
2156         set->dim = like->dim;
2157         isl_basic_set_free(like);
2158         return set;
2159 error:
2160         isl_basic_set_free(like);
2161         isl_set_free(set);
2162         return NULL;
2163 }
2164
2165 struct isl_set *isl_map_underlying_set(struct isl_map *map)
2166 {
2167         int i;
2168
2169         map = isl_map_align_divs(map);
2170         map = isl_map_cow(map);
2171         if (!map)
2172                 return NULL;
2173
2174         for (i = 0; i < map->n; ++i) {
2175                 map->p[i] = (struct isl_basic_map *)
2176                                 isl_basic_map_underlying_set(map->p[i]);
2177                 if (!map->p[i])
2178                         goto error;
2179         }
2180         if (map->n == 0)
2181                 map->n_out += map->nparam + map->n_in;
2182         else
2183                 map->n_out = map->p[0]->n_out;
2184         map->nparam = 0;
2185         map->n_in = 0;
2186         return (struct isl_set *)map;
2187 error:
2188         isl_map_free(map);
2189         return NULL;
2190 }
2191
2192 struct isl_set *isl_set_to_underlying_set(struct isl_set *set)
2193 {
2194         return (struct isl_set *)isl_map_underlying_set((struct isl_map *)set);
2195 }
2196
2197 struct isl_basic_set *isl_basic_map_domain(struct isl_basic_map *bmap)
2198 {
2199         struct isl_basic_set *domain;
2200         unsigned n_out;
2201         if (!bmap)
2202                 return NULL;
2203         n_out = bmap->n_out;
2204         domain = isl_basic_set_from_basic_map(bmap);
2205         return isl_basic_set_project_out(domain, n_out, 0);
2206 }
2207
2208 struct isl_basic_set *isl_basic_map_range(struct isl_basic_map *bmap)
2209 {
2210         return isl_basic_map_domain(isl_basic_map_reverse(bmap));
2211 }
2212
2213 struct isl_set *isl_map_range(struct isl_map *map)
2214 {
2215         int i;
2216         struct isl_set *set;
2217
2218         if (!map)
2219                 goto error;
2220         map = isl_map_cow(map);
2221         if (!map)
2222                 goto error;
2223
2224         set = (struct isl_set *) map;
2225         set->zero = 0;
2226         for (i = 0; i < map->n; ++i) {
2227                 set->p[i] = isl_basic_map_range(map->p[i]);
2228                 if (!set->p[i])
2229                         goto error;
2230         }
2231         F_CLR(set, ISL_MAP_DISJOINT);
2232         return set;
2233 error:
2234         isl_map_free(map);
2235         return NULL;
2236 }
2237
2238 struct isl_map *isl_map_from_set(struct isl_set *set,
2239                 unsigned n_in, unsigned n_out)
2240 {
2241         int i;
2242         struct isl_map *map = NULL;
2243
2244         if (!set)
2245                 return NULL;
2246         isl_assert(set->ctx, set->dim == n_in + n_out, goto error);
2247         set = isl_set_cow(set);
2248         if (!set)
2249                 return NULL;
2250         map = (struct isl_map *)set;
2251         for (i = 0; i < set->n; ++i) {
2252                 map->p[i] = isl_basic_map_from_basic_set(
2253                                 set->p[i], n_in, n_out);
2254                 if (!map->p[i])
2255                         goto error;
2256         }
2257         map->n_in = n_in;
2258         map->n_out = n_out;
2259         return map;
2260 error:
2261         isl_set_free(set);
2262         return NULL;
2263 }
2264
2265 struct isl_set *isl_set_from_map(struct isl_map *map)
2266 {
2267         int i;
2268         struct isl_set *set = NULL;
2269
2270         if (!map)
2271                 return NULL;
2272         map = isl_map_cow(map);
2273         if (!map)
2274                 return NULL;
2275         map->n_out += map->n_in;
2276         map->n_in = 0;
2277         set = (struct isl_set *)map;
2278         for (i = 0; i < map->n; ++i) {
2279                 set->p[i] = isl_basic_set_from_basic_map(map->p[i]);
2280                 if (!set->p[i])
2281                         goto error;
2282         }
2283         return set;
2284 error:
2285         isl_map_free(map);
2286         return NULL;
2287 }
2288
2289 struct isl_map *isl_map_alloc(struct isl_ctx *ctx,
2290                 unsigned nparam, unsigned in, unsigned out, int n,
2291                 unsigned flags)
2292 {
2293         struct isl_map *map;
2294
2295         map = isl_alloc(ctx, struct isl_map,
2296                         sizeof(struct isl_map) +
2297                         n * sizeof(struct isl_basic_map *));
2298         if (!map)
2299                 return NULL;
2300
2301         map->ctx = ctx;
2302         isl_ctx_ref(ctx);
2303         map->ref = 1;
2304         map->size = n;
2305         map->n = 0;
2306         map->nparam = nparam;
2307         map->n_in = in;
2308         map->n_out = out;
2309         map->flags = flags;
2310         return map;
2311 }
2312
2313 struct isl_basic_map *isl_basic_map_empty(struct isl_ctx *ctx,
2314                 unsigned nparam, unsigned in, unsigned out)
2315 {
2316         struct isl_basic_map *bmap;
2317         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, 1, 0);
2318         bmap = isl_basic_map_set_to_empty(bmap);
2319         return bmap;
2320 }
2321
2322 struct isl_basic_set *isl_basic_set_empty(struct isl_ctx *ctx,
2323                 unsigned nparam, unsigned dim)
2324 {
2325         struct isl_basic_set *bset;
2326         bset = isl_basic_set_alloc(ctx, nparam, dim, 0, 1, 0);
2327         bset = isl_basic_set_set_to_empty(bset);
2328         return bset;
2329 }
2330
2331 struct isl_basic_map *isl_basic_map_universe(struct isl_ctx *ctx,
2332                 unsigned nparam, unsigned in, unsigned out)
2333 {
2334         struct isl_basic_map *bmap;
2335         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, 0, 0);
2336         return bmap;
2337 }
2338
2339 struct isl_basic_set *isl_basic_set_universe(struct isl_ctx *ctx,
2340                 unsigned nparam, unsigned dim)
2341 {
2342         struct isl_basic_set *bset;
2343         bset = isl_basic_set_alloc(ctx, nparam, dim, 0, 0, 0);
2344         return bset;
2345 }
2346
2347 struct isl_map *isl_map_empty(struct isl_ctx *ctx,
2348                 unsigned nparam, unsigned in, unsigned out)
2349 {
2350         return isl_map_alloc(ctx, nparam, in, out, 0, ISL_MAP_DISJOINT);
2351 }
2352
2353 struct isl_set *isl_set_empty(struct isl_ctx *ctx,
2354                 unsigned nparam, unsigned dim)
2355 {
2356         return isl_set_alloc(ctx, nparam, dim, 0, ISL_MAP_DISJOINT);
2357 }
2358
2359 struct isl_map *isl_map_dup(struct isl_map *map)
2360 {
2361         int i;
2362         struct isl_map *dup;
2363
2364         if (!map)
2365                 return NULL;
2366         dup = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out, map->n,
2367                                 map->flags);
2368         for (i = 0; i < map->n; ++i)
2369                 dup = isl_map_add(dup,
2370                                   isl_basic_map_dup(map->p[i]));
2371         return dup;
2372 }
2373
2374 struct isl_map *isl_map_add(struct isl_map *map, struct isl_basic_map *bmap)
2375 {
2376         if (!bmap || !map)
2377                 goto error;
2378         isl_assert(map->ctx, map->nparam == bmap->nparam, goto error);
2379         isl_assert(map->ctx, map->n_in == bmap->n_in, goto error);
2380         isl_assert(map->ctx, map->n_out == bmap->n_out, goto error);
2381         isl_assert(map->ctx, map->n < map->size, goto error);
2382         map->p[map->n] = bmap;
2383         map->n++;
2384         return map;
2385 error:
2386         if (map)
2387                 isl_map_free(map);
2388         if (bmap)
2389                 isl_basic_map_free(bmap);
2390         return NULL;
2391 }
2392
2393 void isl_map_free(struct isl_map *map)
2394 {
2395         int i;
2396
2397         if (!map)
2398                 return;
2399
2400         if (--map->ref > 0)
2401                 return;
2402
2403         isl_ctx_deref(map->ctx);
2404         for (i = 0; i < map->n; ++i)
2405                 isl_basic_map_free(map->p[i]);
2406         free(map);
2407 }
2408
2409 struct isl_map *isl_map_extend(struct isl_map *base,
2410                 unsigned nparam, unsigned n_in, unsigned n_out)
2411 {
2412         int i;
2413
2414         base = isl_map_cow(base);
2415         if (!base)
2416                 return NULL;
2417
2418         isl_assert(base->ctx, base->nparam <= nparam, goto error);
2419         isl_assert(base->ctx, base->n_in <= n_in, goto error);
2420         isl_assert(base->ctx, base->n_out <= n_out, goto error);
2421         base->nparam = nparam;
2422         base->n_in = n_in;
2423         base->n_out = n_out;
2424         for (i = 0; i < base->n; ++i) {
2425                 base->p[i] = isl_basic_map_extend(base->p[i],
2426                                 nparam, n_in, n_out, 0, 0, 0);
2427                 if (!base->p[i])
2428                         goto error;
2429         }
2430         return base;
2431 error:
2432         isl_map_free(base);
2433         return NULL;
2434 }
2435
2436 struct isl_set *isl_set_extend(struct isl_set *base,
2437                 unsigned nparam, unsigned dim)
2438 {
2439         return (struct isl_set *)isl_map_extend((struct isl_map *)base,
2440                                                         nparam, 0, dim);
2441 }
2442
2443 static struct isl_basic_map *isl_basic_map_fix_var(struct isl_basic_map *bmap,
2444                 unsigned var, int value)
2445 {
2446         int j;
2447
2448         bmap = isl_basic_map_cow(bmap);
2449         bmap = isl_basic_map_extend(bmap,
2450                         bmap->nparam, bmap->n_in, bmap->n_out, 0, 1, 0);
2451         j = isl_basic_map_alloc_equality(bmap);
2452         if (j < 0)
2453                 goto error;
2454         isl_seq_clr(bmap->eq[j],
2455                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
2456         isl_int_set_si(bmap->eq[j][1 + var], -1);
2457         isl_int_set_si(bmap->eq[j][0], value);
2458         bmap = isl_basic_map_simplify(bmap);
2459         return isl_basic_map_finalize(bmap);
2460 error:
2461         isl_basic_map_free(bmap);
2462         return NULL;
2463 }
2464
2465 struct isl_basic_map *isl_basic_map_fix_input_si(struct isl_basic_map *bmap,
2466                 unsigned input, int value)
2467 {
2468         if (!bmap)
2469                 return NULL;
2470         isl_assert(bmap->ctx, input < bmap->n_in, goto error);
2471         return isl_basic_map_fix_var(bmap, bmap->nparam + input, value);
2472 error:
2473         isl_basic_map_free(bmap);
2474         return NULL;
2475 }
2476
2477 struct isl_basic_set *isl_basic_set_fix_dim_si(struct isl_basic_set *bset,
2478                 unsigned dim, int value)
2479 {
2480         if (!bset)
2481                 return NULL;
2482         isl_assert(bset->ctx, dim < bset->dim, goto error);
2483         return (struct isl_basic_set *)
2484                 isl_basic_map_fix_var((struct isl_basic_map *)bset,
2485                                                 bset->nparam + dim, value);
2486 error:
2487         isl_basic_set_free(bset);
2488         return NULL;
2489 }
2490
2491 struct isl_map *isl_map_fix_input_si(struct isl_map *map,
2492                 unsigned input, int value)
2493 {
2494         int i;
2495
2496         map = isl_map_cow(map);
2497         if (!map)
2498                 return NULL;
2499
2500         isl_assert(ctx, input < map->n_in, goto error);
2501         for (i = 0; i < map->n; ++i) {
2502                 map->p[i] = isl_basic_map_fix_input_si(map->p[i], input, value);
2503                 if (!map->p[i])
2504                         goto error;
2505         }
2506         return map;
2507 error:
2508         isl_map_free(map);
2509         return NULL;
2510 }
2511
2512 struct isl_set *isl_set_fix_dim_si(struct isl_set *set, unsigned dim, int value)
2513 {
2514         int i;
2515
2516         set = isl_set_cow(set);
2517         if (!set)
2518                 return NULL;
2519
2520         isl_assert(set->ctx, dim < set->dim, goto error);
2521         for (i = 0; i < set->n; ++i) {
2522                 set->p[i] = isl_basic_set_fix_dim_si(set->p[i], dim, value);
2523                 if (!set->p[i])
2524                         goto error;
2525         }
2526         return set;
2527 error:
2528         isl_set_free(set);
2529         return NULL;
2530 }
2531
2532 struct isl_map *isl_map_reverse(struct isl_map *map)
2533 {
2534         int i;
2535         unsigned t;
2536
2537         map = isl_map_cow(map);
2538         if (!map)
2539                 return NULL;
2540
2541         t = map->n_in;
2542         map->n_in = map->n_out;
2543         map->n_out = t;
2544         for (i = 0; i < map->n; ++i) {
2545                 map->p[i] = isl_basic_map_reverse(map->p[i]);
2546                 if (!map->p[i])
2547                         goto error;
2548         }
2549         return map;
2550 error:
2551         isl_map_free(map);
2552         return NULL;
2553 }
2554
2555 struct isl_map *isl_basic_map_lexmax(
2556                 struct isl_basic_map *bmap, struct isl_basic_set *dom,
2557                 struct isl_set **empty)
2558 {
2559         return isl_pip_basic_map_lexmax(bmap, dom, empty);
2560 }
2561
2562 struct isl_map *isl_basic_map_lexmin(
2563                 struct isl_basic_map *bmap, struct isl_basic_set *dom,
2564                 struct isl_set **empty)
2565 {
2566         return isl_pip_basic_map_lexmin(bmap, dom, empty);
2567 }
2568
2569 struct isl_set *isl_basic_set_lexmin(struct isl_basic_set *bset)
2570 {
2571         struct isl_basic_map *bmap = NULL;
2572         struct isl_basic_set *dom = NULL;
2573         struct isl_map *min;
2574
2575         if (!bset)
2576                 goto error;
2577         bmap = isl_basic_map_from_basic_set(bset, 0, bset->dim);
2578         if (!bmap)
2579                 goto error;
2580         dom = isl_basic_set_alloc(bmap->ctx, bmap->nparam, 0, 0, 0, 0);
2581         if (!dom)
2582                 goto error;
2583         min = isl_basic_map_lexmin(bmap, dom, NULL);
2584         return isl_map_range(min);
2585 error:
2586         isl_basic_map_free(bmap);
2587         return NULL;
2588 }
2589
2590 struct isl_map *isl_basic_map_compute_divs(struct isl_basic_map *bmap)
2591 {
2592         if (!bmap)
2593                 return NULL;
2594         if (bmap->n_div == 0)
2595                 return isl_map_from_basic_map(bmap);
2596         return isl_pip_basic_map_compute_divs(bmap);
2597 }
2598
2599 struct isl_map *isl_map_compute_divs(struct isl_map *map)
2600 {
2601         int i;
2602         struct isl_map *res;
2603
2604         if (!map)
2605                 return NULL;
2606         if (map->n == 0)
2607                 return map;
2608         res = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[0]));
2609         for (i = 1 ; i < map->n; ++i) {
2610                 struct isl_map *r2;
2611                 r2 = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[i]));
2612                 if (F_ISSET(map, ISL_MAP_DISJOINT))
2613                         res = isl_map_union_disjoint(res, r2);
2614                 else
2615                         res = isl_map_union(res, r2);
2616         }
2617         isl_map_free(map);
2618
2619         return res;
2620 }
2621
2622 struct isl_set *isl_basic_set_compute_divs(struct isl_basic_set *bset)
2623 {
2624         return (struct isl_set *)
2625                 isl_basic_map_compute_divs((struct isl_basic_map *)bset);
2626 }
2627
2628 struct isl_set *isl_set_compute_divs(struct isl_set *set)
2629 {
2630         return (struct isl_set *)
2631                 isl_map_compute_divs((struct isl_map *)set);
2632 }
2633
2634 struct isl_set *isl_map_domain(struct isl_map *map)
2635 {
2636         int i;
2637         struct isl_set *set;
2638
2639         if (!map)
2640                 goto error;
2641
2642         map = isl_map_cow(map);
2643         if (!map)
2644                 return NULL;
2645
2646         set = (struct isl_set *)map;
2647         set->dim = map->n_in;
2648         set->zero = 0;
2649         for (i = 0; i < map->n; ++i) {
2650                 set->p[i] = isl_basic_map_domain(map->p[i]);
2651                 if (!set->p[i])
2652                         goto error;
2653         }
2654         F_CLR(set, ISL_MAP_DISJOINT);
2655         return set;
2656 error:
2657         isl_map_free(map);
2658         return NULL;
2659 }
2660
2661 struct isl_map *isl_map_union_disjoint(
2662                         struct isl_map *map1, struct isl_map *map2)
2663 {
2664         int i;
2665         unsigned flags = 0;
2666         struct isl_map *map = NULL;
2667
2668         if (!map1 || !map2)
2669                 goto error;
2670
2671         if (map1->n == 0) {
2672                 isl_map_free(map1);
2673                 return map2;
2674         }
2675         if (map2->n == 0) {
2676                 isl_map_free(map2);
2677                 return map1;
2678         }
2679
2680         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
2681         isl_assert(map1->ctx, map1->n_in == map2->n_in, goto error);
2682         isl_assert(map1->ctx, map1->n_out == map2->n_out, goto error);
2683
2684         if (F_ISSET(map1, ISL_MAP_DISJOINT) &&
2685             F_ISSET(map2, ISL_MAP_DISJOINT))
2686                 FL_SET(flags, ISL_MAP_DISJOINT);
2687
2688         map = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map1->n_out,
2689                                 map1->n + map2->n, flags);
2690         if (!map)
2691                 goto error;
2692         for (i = 0; i < map1->n; ++i) {
2693                 map = isl_map_add(map,
2694                                   isl_basic_map_copy(map1->p[i]));
2695                 if (!map)
2696                         goto error;
2697         }
2698         for (i = 0; i < map2->n; ++i) {
2699                 map = isl_map_add(map,
2700                                   isl_basic_map_copy(map2->p[i]));
2701                 if (!map)
2702                         goto error;
2703         }
2704         isl_map_free(map1);
2705         isl_map_free(map2);
2706         return map;
2707 error:
2708         isl_map_free(map);
2709         isl_map_free(map1);
2710         isl_map_free(map2);
2711         return NULL;
2712 }
2713
2714 struct isl_map *isl_map_union(struct isl_map *map1, struct isl_map *map2)
2715 {
2716         map1 = isl_map_union_disjoint(map1, map2);
2717         if (!map1)
2718                 return NULL;
2719         if (map1->n > 1)
2720                 F_CLR(map1, ISL_MAP_DISJOINT);
2721         return map1;
2722 }
2723
2724 struct isl_set *isl_set_union_disjoint(
2725                         struct isl_set *set1, struct isl_set *set2)
2726 {
2727         return (struct isl_set *)
2728                 isl_map_union_disjoint(
2729                         (struct isl_map *)set1, (struct isl_map *)set2);
2730 }
2731
2732 struct isl_set *isl_set_union(struct isl_set *set1, struct isl_set *set2)
2733 {
2734         return (struct isl_set *)
2735                 isl_map_union((struct isl_map *)set1, (struct isl_map *)set2);
2736 }
2737
2738 struct isl_map *isl_map_intersect_range(
2739                 struct isl_map *map, struct isl_set *set)
2740 {
2741         unsigned flags = 0;
2742         struct isl_map *result;
2743         int i, j;
2744
2745         if (!map || !set)
2746                 goto error;
2747
2748         if (F_ISSET(map, ISL_MAP_DISJOINT) &&
2749             F_ISSET(set, ISL_MAP_DISJOINT))
2750                 FL_SET(flags, ISL_MAP_DISJOINT);
2751
2752         result = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out,
2753                                 map->n * set->n, flags);
2754         if (!result)
2755                 goto error;
2756         for (i = 0; i < map->n; ++i)
2757                 for (j = 0; j < set->n; ++j) {
2758                         result = isl_map_add(result,
2759                             isl_basic_map_intersect_range(
2760                                 isl_basic_map_copy(map->p[i]),
2761                                 isl_basic_set_copy(set->p[j])));
2762                         if (!result)
2763                                 goto error;
2764                 }
2765         isl_map_free(map);
2766         isl_set_free(set);
2767         return result;
2768 error:
2769         isl_map_free(map);
2770         isl_set_free(set);
2771         return NULL;
2772 }
2773
2774 struct isl_map *isl_map_intersect_domain(
2775                 struct isl_map *map, struct isl_set *set)
2776 {
2777         return isl_map_reverse(
2778                 isl_map_intersect_range(isl_map_reverse(map), set));
2779 }
2780
2781 struct isl_map *isl_map_apply_domain(
2782                 struct isl_map *map1, struct isl_map *map2)
2783 {
2784         if (!map1 || !map2)
2785                 goto error;
2786         map1 = isl_map_reverse(map1);
2787         map1 = isl_map_apply_range(map1, map2);
2788         return isl_map_reverse(map1);
2789 error:
2790         isl_map_free(map1);
2791         isl_map_free(map2);
2792         return NULL;
2793 }
2794
2795 struct isl_map *isl_map_apply_range(
2796                 struct isl_map *map1, struct isl_map *map2)
2797 {
2798         struct isl_map *result;
2799         int i, j;
2800
2801         if (!map1 || !map2)
2802                 goto error;
2803
2804         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
2805         isl_assert(map1->ctx, map1->n_out == map2->n_in, goto error);
2806
2807         result = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map2->n_out,
2808                                 map1->n * map2->n, 0);
2809         if (!result)
2810                 goto error;
2811         for (i = 0; i < map1->n; ++i)
2812                 for (j = 0; j < map2->n; ++j) {
2813                         result = isl_map_add(result,
2814                             isl_basic_map_apply_range(
2815                                 isl_basic_map_copy(map1->p[i]),
2816                                 isl_basic_map_copy(map2->p[j])));
2817                         if (!result)
2818                                 goto error;
2819                 }
2820         isl_map_free(map1);
2821         isl_map_free(map2);
2822         if (result && result->n <= 1)
2823                 F_SET(result, ISL_MAP_DISJOINT);
2824         return result;
2825 error:
2826         isl_map_free(map1);
2827         isl_map_free(map2);
2828         return NULL;
2829 }
2830
2831 /*
2832  * returns range - domain
2833  */
2834 struct isl_basic_set *isl_basic_map_deltas(struct isl_basic_map *bmap)
2835 {
2836         struct isl_basic_set *bset;
2837         unsigned dim;
2838         int i;
2839
2840         if (!bmap)
2841                 goto error;
2842         isl_assert(bmap->ctx, bmap->n_in == bmap->n_out, goto error);
2843         dim = bmap->n_in;
2844         bset = isl_basic_set_from_basic_map(bmap);
2845         bset = isl_basic_set_extend(bset, bset->nparam, 3*dim, 0,
2846                                         dim, 0);
2847         bset = isl_basic_set_swap_vars(bset, 2*dim);
2848         for (i = 0; i < dim; ++i) {
2849                 int j = isl_basic_map_alloc_equality(
2850                                             (struct isl_basic_map *)bset);
2851                 if (j < 0)
2852                         goto error;
2853                 isl_seq_clr(bset->eq[j],
2854                             1 + bset->nparam + bset->dim + bset->extra);
2855                 isl_int_set_si(bset->eq[j][1+bset->nparam+i], 1);
2856                 isl_int_set_si(bset->eq[j][1+bset->nparam+dim+i], 1);
2857                 isl_int_set_si(bset->eq[j][1+bset->nparam+2*dim+i], -1);
2858         }
2859         return isl_basic_set_project_out(bset, 2*dim, 0);
2860 error:
2861         isl_basic_map_free(bmap);
2862         return NULL;
2863 }
2864
2865 /* If the only constraints a div d=floor(f/m)
2866  * appears in are its two defining constraints
2867  *
2868  *      f - m d >=0
2869  *      -(f - (m - 1)) + m d >= 0
2870  *
2871  * then it can safely be removed.
2872  */
2873 static int div_is_redundant(struct isl_basic_map *bmap, int div)
2874 {
2875         int i;
2876         unsigned pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
2877
2878         for (i = 0; i < bmap->n_eq; ++i)
2879                 if (!isl_int_is_zero(bmap->eq[i][pos]))
2880                         return 0;
2881
2882         for (i = 0; i < bmap->n_ineq; ++i) {
2883                 if (isl_int_is_zero(bmap->ineq[i][pos]))
2884                         continue;
2885                 if (isl_int_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
2886                         int neg;
2887                         isl_int_sub(bmap->div[div][1],
2888                                         bmap->div[div][1], bmap->div[div][0]);
2889                         isl_int_add_ui(bmap->div[div][1], bmap->div[div][1], 1);
2890                         neg = isl_seq_is_neg(bmap->ineq[i], bmap->div[div]+1, pos);
2891                         isl_int_sub_ui(bmap->div[div][1], bmap->div[div][1], 1);
2892                         isl_int_add(bmap->div[div][1],
2893                                         bmap->div[div][1], bmap->div[div][0]);
2894                         if (!neg)
2895                                 return 0;
2896                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
2897                                                     bmap->n_div-div-1) != -1)
2898                                 return 0;
2899                 } else if (isl_int_abs_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
2900                         if (!isl_seq_eq(bmap->ineq[i], bmap->div[div]+1, pos))
2901                                 return 0;
2902                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
2903                                                     bmap->n_div-div-1) != -1)
2904                                 return 0;
2905                 } else
2906                         return 0;
2907         }
2908
2909         for (i = 0; i < bmap->n_div; ++i)
2910                 if (!isl_int_is_zero(bmap->div[i][1+pos]))
2911                         return 0;
2912
2913         return 1;
2914 }
2915
2916 /*
2917  * Remove divs that don't occur in any of the constraints or other divs.
2918  * These can arise when dropping some of the variables in a quast
2919  * returned by piplib.
2920  */
2921 static struct isl_basic_map *remove_redundant_divs(struct isl_basic_map *bmap)
2922 {
2923         int i;
2924
2925         if (!bmap)
2926                 return NULL;
2927
2928         for (i = bmap->n_div-1; i >= 0; --i) {
2929                 if (!div_is_redundant(bmap, i))
2930                         continue;
2931                 bmap = isl_basic_map_drop_div(bmap, i);
2932         }
2933         return bmap;
2934 }
2935
2936 struct isl_basic_map *isl_basic_map_finalize(struct isl_basic_map *bmap)
2937 {
2938         bmap = remove_redundant_divs(bmap);
2939         if (!bmap)
2940                 return NULL;
2941         F_SET(bmap, ISL_BASIC_SET_FINAL);
2942         return bmap;
2943 }
2944
2945 struct isl_basic_set *isl_basic_set_finalize(struct isl_basic_set *bset)
2946 {
2947         return (struct isl_basic_set *)
2948                 isl_basic_map_finalize((struct isl_basic_map *)bset);
2949 }
2950
2951 struct isl_set *isl_set_finalize(struct isl_set *set)
2952 {
2953         int i;
2954
2955         if (!set)
2956                 return NULL;
2957         for (i = 0; i < set->n; ++i) {
2958                 set->p[i] = isl_basic_set_finalize(set->p[i]);
2959                 if (!set->p[i])
2960                         goto error;
2961         }
2962         return set;
2963 error:
2964         isl_set_free(set);
2965         return NULL;
2966 }
2967
2968 struct isl_map *isl_map_finalize(struct isl_map *map)
2969 {
2970         int i;
2971
2972         if (!map)
2973                 return NULL;
2974         for (i = 0; i < map->n; ++i) {
2975                 map->p[i] = isl_basic_map_finalize(map->p[i]);
2976                 if (!map->p[i])
2977                         goto error;
2978         }
2979         return map;
2980 error:
2981         isl_map_free(map);
2982         return NULL;
2983 }
2984
2985 struct isl_basic_map *isl_basic_map_identity(struct isl_ctx *ctx,
2986                 unsigned nparam, unsigned dim)
2987 {
2988         struct isl_basic_map *bmap;
2989         int i;
2990
2991         bmap = isl_basic_map_alloc(ctx, nparam, dim, dim, 0, dim, 0);
2992         if (!bmap)
2993                 goto error;
2994
2995         for (i = 0; i < dim; ++i) {
2996                 int j = isl_basic_map_alloc_equality(bmap);
2997                 if (j < 0)
2998                         goto error;
2999                 isl_seq_clr(bmap->eq[j],
3000                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
3001                 isl_int_set_si(bmap->eq[j][1+nparam+i], 1);
3002                 isl_int_set_si(bmap->eq[j][1+nparam+dim+i], -1);
3003         }
3004         return isl_basic_map_finalize(bmap);
3005 error:
3006         isl_basic_map_free(bmap);
3007         return NULL;
3008 }
3009
3010 struct isl_map *isl_map_identity(struct isl_ctx *ctx,
3011                 unsigned nparam, unsigned dim)
3012 {
3013         struct isl_map *map = isl_map_alloc(ctx, nparam, dim, dim, 1,
3014                                                 ISL_MAP_DISJOINT);
3015         if (!map)
3016                 goto error;
3017         map = isl_map_add(map,
3018                 isl_basic_map_identity(ctx, nparam, dim));
3019         return map;
3020 error:
3021         isl_map_free(map);
3022         return NULL;
3023 }
3024
3025 int isl_set_is_equal(struct isl_set *set1, struct isl_set *set2)
3026 {
3027         return isl_map_is_equal((struct isl_map *)set1, (struct isl_map *)set2);
3028 }
3029
3030 int isl_set_is_subset(struct isl_set *set1, struct isl_set *set2)
3031 {
3032         return isl_map_is_subset(
3033                         (struct isl_map *)set1, (struct isl_map *)set2);
3034 }
3035
3036 int isl_basic_map_is_subset(
3037                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3038 {
3039         int is_subset;
3040         struct isl_map *map1;
3041         struct isl_map *map2;
3042
3043         if (!bmap1 || !bmap2)
3044                 return -1;
3045
3046         map1 = isl_map_from_basic_map(isl_basic_map_copy(bmap1));
3047         map2 = isl_map_from_basic_map(isl_basic_map_copy(bmap2));
3048
3049         is_subset = isl_map_is_subset(map1, map2);
3050
3051         isl_map_free(map1);
3052         isl_map_free(map2);
3053
3054         return is_subset;
3055 }
3056
3057 int isl_basic_map_is_equal(
3058                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3059 {
3060         int is_subset;
3061
3062         if (!bmap1 || !bmap2)
3063                 return -1;
3064         is_subset = isl_basic_map_is_subset(bmap1, bmap2);
3065         if (is_subset != 1)
3066                 return is_subset;
3067         is_subset = isl_basic_map_is_subset(bmap2, bmap1);
3068         return is_subset;
3069 }
3070
3071 int isl_basic_set_is_equal(
3072                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
3073 {
3074         return isl_basic_map_is_equal(
3075                 (struct isl_basic_map *)bset1, (struct isl_basic_map *)bset2);
3076 }
3077
3078 int isl_map_is_empty(struct isl_map *map)
3079 {
3080         int i;
3081         int is_empty;
3082
3083         if (!map)
3084                 return -1;
3085         for (i = 0; i < map->n; ++i) {
3086                 is_empty = isl_basic_map_is_empty(map->p[i]);
3087                 if (is_empty < 0)
3088                         return -1;
3089                 if (!is_empty)
3090                         return 0;
3091         }
3092         return 1;
3093 }
3094
3095 int isl_set_is_empty(struct isl_set *set)
3096 {
3097         return isl_map_is_empty((struct isl_map *)set);
3098 }
3099
3100 int isl_map_is_subset(struct isl_map *map1, struct isl_map *map2)
3101 {
3102         int i;
3103         int is_subset = 0;
3104         struct isl_map *diff;
3105
3106         if (!map1 || !map2)
3107                 return -1;
3108
3109         if (isl_map_is_empty(map1))
3110                 return 1;
3111
3112         if (isl_map_is_empty(map2))
3113                 return 0;
3114
3115         diff = isl_map_subtract(isl_map_copy(map1), isl_map_copy(map2));
3116         if (!diff)
3117                 return -1;
3118
3119         is_subset = isl_map_is_empty(diff);
3120         isl_map_free(diff);
3121
3122         return is_subset;
3123 }
3124
3125 int isl_map_is_equal(struct isl_map *map1, struct isl_map *map2)
3126 {
3127         int is_subset;
3128
3129         if (!map1 || !map2)
3130                 return -1;
3131         is_subset = isl_map_is_subset(map1, map2);
3132         if (is_subset != 1)
3133                 return is_subset;
3134         is_subset = isl_map_is_subset(map2, map1);
3135         return is_subset;
3136 }
3137
3138 int isl_basic_map_is_strict_subset(
3139                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3140 {
3141         int is_subset;
3142
3143         if (!bmap1 || !bmap2)
3144                 return -1;
3145         is_subset = isl_basic_map_is_subset(bmap1, bmap2);
3146         if (is_subset != 1)
3147                 return is_subset;
3148         is_subset = isl_basic_map_is_subset(bmap2, bmap1);
3149         if (is_subset == -1)
3150                 return is_subset;
3151         return !is_subset;
3152 }
3153
3154 static int basic_map_contains(struct isl_basic_map *bmap, struct isl_vec *vec)
3155 {
3156         int i;
3157         unsigned total;
3158         isl_int s;
3159
3160         total = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3161         if (total != vec->size)
3162                 return -1;
3163
3164         isl_int_init(s);
3165
3166         for (i = 0; i < bmap->n_eq; ++i) {
3167                 isl_seq_inner_product(vec->block.data, bmap->eq[i], total, &s);
3168                 if (!isl_int_is_zero(s)) {
3169                         isl_int_clear(s);
3170                         return 0;
3171                 }
3172         }
3173
3174         for (i = 0; i < bmap->n_ineq; ++i) {
3175                 isl_seq_inner_product(vec->block.data, bmap->ineq[i], total, &s);
3176                 if (isl_int_is_neg(s)) {
3177                         isl_int_clear(s);
3178                         return 0;
3179                 }
3180         }
3181
3182         isl_int_clear(s);
3183
3184         return 1;
3185 }
3186
3187 int isl_basic_map_is_universe(struct isl_basic_map *bmap)
3188 {
3189         if (!bmap)
3190                 return -1;
3191         return bmap->n_eq == 0 && bmap->n_ineq == 0;
3192 }
3193
3194 int isl_basic_map_is_empty(struct isl_basic_map *bmap)
3195 {
3196         struct isl_basic_set *bset = NULL;
3197         struct isl_vec *sample = NULL;
3198         int empty;
3199         unsigned total;
3200
3201         if (!bmap)
3202                 return -1;
3203
3204         if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
3205                 return 1;
3206
3207         total = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3208         if (bmap->sample && bmap->sample->size == total) {
3209                 int contains = basic_map_contains(bmap, bmap->sample);
3210                 if (contains < 0)
3211                         return -1;
3212                 if (contains)
3213                         return 0;
3214         }
3215         bset = isl_basic_map_underlying_set(isl_basic_map_copy(bmap));
3216         if (!bset)
3217                 return -1;
3218         sample = isl_basic_set_sample(bset);
3219         if (!sample)
3220                 return -1;
3221         empty = sample->size == 0;
3222         if (bmap->sample)
3223                 isl_vec_free(bmap->ctx, bmap->sample);
3224         bmap->sample = sample;
3225
3226         return empty;
3227 }
3228
3229 struct isl_map *isl_basic_map_union(
3230         struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3231 {
3232         struct isl_map *map;
3233         if (!bmap1 || !bmap2)
3234                 return NULL;
3235
3236         isl_assert(bmap1->ctx, bmap1->nparam == bmap2->nparam, goto error);
3237         isl_assert(bmap1->ctx, bmap1->n_in == bmap2->n_in, goto error);
3238         isl_assert(bmap1->ctx, bmap1->n_out == bmap2->n_out, goto error);
3239
3240         map = isl_map_alloc(bmap1->ctx, bmap1->nparam,
3241                                 bmap1->n_in, bmap1->n_out, 2, 0);
3242         if (!map)
3243                 goto error;
3244         map = isl_map_add(map, bmap1);
3245         map = isl_map_add(map, bmap2);
3246         return map;
3247 error:
3248         isl_basic_map_free(bmap1);
3249         isl_basic_map_free(bmap2);
3250         return NULL;
3251 }
3252
3253 struct isl_set *isl_basic_set_union(
3254                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
3255 {
3256         return (struct isl_set *)isl_basic_map_union(
3257                                             (struct isl_basic_map *)bset1,
3258                                             (struct isl_basic_map *)bset2);
3259 }
3260
3261 /* Order divs such that any div only depends on previous divs */
3262 static struct isl_basic_map *order_divs(struct isl_basic_map *bmap)
3263 {
3264         int i;
3265         unsigned off = bmap->nparam + bmap->n_in + bmap->n_out;
3266
3267         for (i = 0; i < bmap->n_div; ++i) {
3268                 int pos;
3269                 pos = isl_seq_first_non_zero(bmap->div[i]+1+1+off+i,
3270                                                             bmap->n_div-i);
3271                 if (pos == -1)
3272                         continue;
3273                 swap_div(bmap, i, pos);
3274                 --i;
3275         }
3276         return bmap;
3277 }
3278
3279 static int find_div(struct isl_basic_map *dst,
3280                         struct isl_basic_map *src, unsigned div)
3281 {
3282         int i;
3283
3284         unsigned total = src->nparam + src->n_in + src->n_out + src->n_div;
3285
3286         for (i = 0; i < dst->n_div; ++i)
3287                 if (isl_seq_eq(dst->div[i], src->div[div], 1+1+total) &&
3288                     isl_seq_first_non_zero(dst->div[i]+1+1+total,
3289                                                 dst->n_div - src->n_div) == -1)
3290                         return i;
3291         return -1;
3292 }
3293
3294 struct isl_basic_map *isl_basic_map_align_divs(
3295                 struct isl_basic_map *dst, struct isl_basic_map *src)
3296 {
3297         int i;
3298         unsigned total = src->nparam + src->n_in + src->n_out + src->n_div;
3299
3300         if (src->n_div == 0)
3301                 return dst;
3302
3303         src = order_divs(src);
3304         dst = isl_basic_map_extend(dst, dst->nparam, dst->n_in,
3305                         dst->n_out, src->n_div, 0, 2 * src->n_div);
3306         if (!dst)
3307                 return NULL;
3308         for (i = 0; i < src->n_div; ++i) {
3309                 int j = find_div(dst, src, i);
3310                 if (j < 0) {
3311                         j = isl_basic_map_alloc_div(dst);
3312                         if (j < 0)
3313                                 goto error;
3314                         isl_seq_cpy(dst->div[j], src->div[i], 1+1+total);
3315                         isl_seq_clr(dst->div[j]+1+1+total,
3316                                                     dst->extra - src->n_div);
3317                         if (add_div_constraints(dst, j) < 0)
3318                                 goto error;
3319                 }
3320                 if (j != i)
3321                         swap_div(dst, i, j);
3322         }
3323         return dst;
3324 error:
3325         isl_basic_map_free(dst);
3326         return NULL;
3327 }
3328
3329 struct isl_map *isl_map_align_divs(struct isl_map *map)
3330 {
3331         int i;
3332
3333         map = isl_map_compute_divs(map);
3334         map = isl_map_cow(map);
3335         if (!map)
3336                 return NULL;
3337
3338         for (i = 1; i < map->n; ++i)
3339                 map->p[0] = isl_basic_map_align_divs(map->p[0], map->p[i]);
3340         for (i = 1; i < map->n; ++i)
3341                 map->p[i] = isl_basic_map_align_divs(map->p[i], map->p[0]);
3342
3343         return map;
3344 }
3345
3346 static struct isl_map *add_cut_constraint(struct isl_map *dst,
3347                 struct isl_basic_map *src, isl_int *c,
3348                 unsigned len, int oppose)
3349 {
3350         struct isl_basic_map *copy = NULL;
3351         int is_empty;
3352         int k;
3353         unsigned total;
3354
3355         copy = isl_basic_map_copy(src);
3356         copy = isl_basic_map_cow(copy);
3357         if (!copy)
3358                 goto error;
3359         copy = isl_basic_map_extend(copy,
3360                 copy->nparam, copy->n_in, copy->n_out, 0, 0, 1);
3361         k = isl_basic_map_alloc_inequality(copy);
3362         if (k < 0)
3363                 goto error;
3364         if (oppose)
3365                 isl_seq_neg(copy->ineq[k], c, len);
3366         else
3367                 isl_seq_cpy(copy->ineq[k], c, len);
3368         total = 1 + copy->nparam + copy->n_in + copy->n_out + copy->extra;
3369         isl_seq_clr(copy->ineq[k]+len, total - len);
3370         isl_inequality_negate(copy, k);
3371         copy = isl_basic_map_simplify(copy);
3372         copy = isl_basic_map_finalize(copy);
3373         is_empty = isl_basic_map_is_empty(copy);
3374         if (is_empty < 0)
3375                 goto error;
3376         if (!is_empty)
3377                 dst = isl_map_add(dst, copy);
3378         else
3379                 isl_basic_map_free(copy);
3380         return dst;
3381 error:
3382         isl_basic_map_free(copy);
3383         isl_map_free(dst);
3384         return NULL;
3385 }
3386
3387 static struct isl_map *subtract(struct isl_map *map, struct isl_basic_map *bmap)
3388 {
3389         int i, j, k;
3390         unsigned flags = 0;
3391         struct isl_map *rest = NULL;
3392         unsigned max;
3393         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3394
3395         assert(bmap);
3396
3397         if (!map)
3398                 goto error;
3399
3400         if (F_ISSET(map, ISL_MAP_DISJOINT))
3401                 FL_SET(flags, ISL_MAP_DISJOINT);
3402
3403         max = map->n * (2 * bmap->n_eq + bmap->n_ineq);
3404         rest = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out,
3405                                 max, flags);
3406         if (!rest)
3407                 goto error;
3408
3409         for (i = 0; i < map->n; ++i) {
3410                 map->p[i] = isl_basic_map_align_divs(map->p[i], bmap);
3411                 if (!map->p[i])
3412                         goto error;
3413         }
3414
3415         for (j = 0; j < map->n; ++j)
3416                 map->p[j] = isl_basic_map_cow(map->p[j]);
3417
3418         for (i = 0; i < bmap->n_eq; ++i) {
3419                 for (j = 0; j < map->n; ++j) {
3420                         rest = add_cut_constraint(rest,
3421                                 map->p[j], bmap->eq[i], 1+total, 0);
3422                         if (!rest)
3423                                 goto error;
3424
3425                         rest = add_cut_constraint(rest,
3426                                 map->p[j], bmap->eq[i], 1+total, 1);
3427                         if (!rest)
3428                                 goto error;
3429
3430                         map->p[j] = isl_basic_map_extend(map->p[j],
3431                                 map->p[j]->nparam, map->p[j]->n_in,
3432                                 map->p[j]->n_out, 0, 1, 0);
3433                         if (!map->p[j])
3434                                 goto error;
3435                         k = isl_basic_map_alloc_equality(map->p[j]);
3436                         if (k < 0)
3437                                 goto error;
3438                         isl_seq_cpy(map->p[j]->eq[k], bmap->eq[i], 1+total);
3439                         isl_seq_clr(map->p[j]->eq[k]+1+total,
3440                                         map->p[j]->extra - bmap->n_div);
3441                 }
3442         }
3443
3444         for (i = 0; i < bmap->n_ineq; ++i) {
3445                 for (j = 0; j < map->n; ++j) {
3446                         rest = add_cut_constraint(rest,
3447                                 map->p[j], bmap->ineq[i], 1+total, 0);
3448                         if (!rest)
3449                                 goto error;
3450
3451                         map->p[j] = isl_basic_map_extend(map->p[j],
3452                                 map->p[j]->nparam, map->p[j]->n_in,
3453                                 map->p[j]->n_out, 0, 0, 1);
3454                         if (!map->p[j])
3455                                 goto error;
3456                         k = isl_basic_map_alloc_inequality(map->p[j]);
3457                         if (k < 0)
3458                                 goto error;
3459                         isl_seq_cpy(map->p[j]->ineq[k], bmap->ineq[i], 1+total);
3460                         isl_seq_clr(map->p[j]->ineq[k]+1+total,
3461                                         map->p[j]->extra - bmap->n_div);
3462                 }
3463         }
3464
3465         isl_map_free(map);
3466         return rest;
3467 error:
3468         isl_map_free(map);
3469         isl_map_free(rest);
3470         return NULL;
3471 }
3472
3473 struct isl_map *isl_map_subtract(struct isl_map *map1, struct isl_map *map2)
3474 {
3475         int i;
3476         if (!map1 || !map2)
3477                 goto error;
3478
3479         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
3480         isl_assert(map1->ctx, map1->n_in == map2->n_in, goto error);
3481         isl_assert(map1->ctx, map1->n_out == map2->n_out, goto error);
3482
3483         if (isl_map_is_empty(map2)) {
3484                 isl_map_free(map2);
3485                 return map1;
3486         }
3487
3488         map1 = isl_map_compute_divs(map1);
3489         map2 = isl_map_compute_divs(map2);
3490         if (!map1 || !map2)
3491                 goto error;
3492
3493         for (i = 0; map1 && i < map2->n; ++i)
3494                 map1 = subtract(map1, map2->p[i]);
3495
3496         isl_map_free(map2);
3497         return map1;
3498 error:
3499         isl_map_free(map1);
3500         isl_map_free(map2);
3501         return NULL;
3502 }
3503
3504 struct isl_set *isl_set_subtract(struct isl_set *set1, struct isl_set *set2)
3505 {
3506         return (struct isl_set *)
3507                 isl_map_subtract(
3508                         (struct isl_map *)set1, (struct isl_map *)set2);
3509 }
3510
3511 struct isl_set *isl_set_apply(struct isl_set *set, struct isl_map *map)
3512 {
3513         if (!set || !map)
3514                 goto error;
3515         isl_assert(set->ctx, set->dim == map->n_in, goto error);
3516         map = isl_map_intersect_domain(map, set);
3517         set = isl_map_range(map);
3518         return set;
3519 error:
3520         isl_set_free(set);
3521         isl_map_free(map);
3522         return NULL;
3523 }
3524
3525 /* There is no need to cow as removing empty parts doesn't change
3526  * the meaning of the set.
3527  */
3528 struct isl_map *isl_map_remove_empty_parts(struct isl_map *map)
3529 {
3530         int i;
3531
3532         if (!map)
3533                 return NULL;
3534
3535         for (i = map->n-1; i >= 0; --i) {
3536                 if (!F_ISSET(map->p[i], ISL_BASIC_MAP_EMPTY))
3537                         continue;
3538                 isl_basic_map_free(map->p[i]);
3539                 if (i != map->n-1)
3540                         map->p[i] = map->p[map->n-1];
3541                 map->n--;
3542         }
3543
3544         return map;
3545 }
3546
3547 struct isl_set *isl_set_remove_empty_parts(struct isl_set *set)
3548 {
3549         return (struct isl_set *)
3550                 isl_map_remove_empty_parts((struct isl_map *)set);
3551 }
3552
3553 struct isl_basic_set *isl_set_copy_basic_set(struct isl_set *set)
3554 {
3555         struct isl_basic_set *bset;
3556         if (!set || set->n == 0)
3557                 return NULL;
3558         bset = set->p[set->n-1];
3559         isl_assert(set->ctx, F_ISSET(bset, ISL_BASIC_SET_FINAL), return NULL);
3560         return isl_basic_set_copy(bset);
3561 }
3562
3563 struct isl_set *isl_set_drop_basic_set(struct isl_set *set,
3564                                                 struct isl_basic_set *bset)
3565 {
3566         int i;
3567
3568         if (!set || !bset)
3569                 goto error;
3570         for (i = set->n-1; i >= 0; --i) {
3571                 if (set->p[i] != bset)
3572                         continue;
3573                 set = isl_set_cow(set);
3574                 if (!set)
3575                         goto error;
3576                 isl_basic_set_free(set->p[i]);
3577                 if (i != set->n-1)
3578                         set->p[i] = set->p[set->n-1];
3579                 set->n--;
3580                 return set;
3581         }
3582         isl_basic_set_free(bset);
3583         return set;
3584 error:
3585         isl_set_free(set);
3586         isl_basic_set_free(bset);
3587         return NULL;
3588 }