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                 if (progress)
 959                         *progress = 1;
 960                 l = index[h] - 1;
 961                 if (isl_int_lt(bmap->ineq[k][0], bmap->ineq[l][0]))
 962                         swap_inequality(bmap, k, l);
 963                 isl_basic_map_drop_inequality(bmap, k);
 964                 --k;
 965         }
 966         isl_int_init(sum);
 967         for (k = 0; k < bmap->n_ineq-1; ++k) {
 968                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 969                 h = hash_index(index, size, bits, bmap, k);
 970                 isl_seq_neg(bmap->ineq[k]+1, bmap->ineq[k]+1, total);
 971                 if (!index[h])
 972                         continue;
 973                 l = index[h] - 1;
 974                 isl_int_add(sum, bmap->ineq[k][0], bmap->ineq[l][0]);
 975                 if (isl_int_is_pos(sum))
 976                         continue;
 977                 if (isl_int_is_zero(sum)) {
 978                         /* We need to break out of the loop after these
 979                          * changes since the contents of the hash
 980                          * will no longer be valid.
 981                          * Plus, we probably we want to regauss first.
 982                          */
 983                         isl_basic_map_drop_inequality(bmap, l);
 984                         isl_basic_map_inequality_to_equality(bmap, k);
 985                 } else
 986                         bmap = isl_basic_map_set_to_empty(bmap);
 987                 break;
 988         }
 989         isl_int_clear(sum);
 990
 991         free(index);
 992         return bmap;
 993 }
 994
 995 static struct isl_basic_map *remove_duplicate_divs(
 996         struct isl_basic_map *bmap, int *progress)
 997 {
 998         unsigned int size;
 999         int *index;
1000         int k, l, h;
1001         int bits;
1002         struct isl_blk eq;
1003         unsigned total_var = bmap->nparam + bmap->n_in + bmap->n_out;
1004         unsigned total = total_var + bmap->n_div;
1005         struct isl_ctx *ctx;
1006
1007         if (bmap->n_div <= 1)
1008                 return bmap;
1009
1010         ctx = bmap->ctx;
1011         for (k = bmap->n_div - 1; k >= 0; --k)
1012                 if (!isl_int_is_zero(bmap->div[k][0]))
1013                         break;
1014         if (k <= 0)
1015                 return bmap;
1016
1017         size = round_up(4 * bmap->n_div / 3 - 1);
1018         bits = ffs(size) - 1;
1019         index = isl_alloc_array(ctx, int, size);
1020         memset(index, 0, size * sizeof(int));
1021         if (!index)
1022                 return bmap;
1023         eq = isl_blk_alloc(ctx, 1+total);
1024         if (isl_blk_is_error(eq))
1025                 goto out;
1026
1027         isl_seq_clr(eq.data, 1+total);
1028         index[isl_seq_hash(bmap->div[k], 2+total, bits)] = k + 1;
1029         for (--k; k >= 0; --k) {
1030                 u_int32_t hash;
1031
1032                 if (isl_int_is_zero(bmap->div[k][0]))
1033                         continue;
1034
1035                 hash = isl_seq_hash(bmap->div[k], 2+total, bits);
1036                 for (h = hash; index[h]; h = (h+1) % size)
1037                         if (isl_seq_eq(bmap->div[k],
1038                                        bmap->div[index[h]-1], 2+total))
1039                                 break;
1040                 if (index[h]) {
1041                         *progress = 1;
1042                         l = index[h] - 1;
1043                         isl_int_set_si(eq.data[1+total_var+k], -1);
1044                         isl_int_set_si(eq.data[1+total_var+l], 1);
1045                         eliminate_div(bmap, eq.data, l);
1046                         isl_int_set_si(eq.data[1+total_var+k], 0);
1047                         isl_int_set_si(eq.data[1+total_var+l], 0);
1048                 }
1049                 index[h] = k+1;
1050         }
1051
1052         isl_blk_free(ctx, eq);
1053 out:
1054         free(index);
1055         return bmap;
1056 }
1057
1058 /* Elimininate divs based on equalities
1059  */
1060 static struct isl_basic_map *eliminate_divs_eq(
1061                 struct isl_basic_map *bmap, int *progress)
1062 {
1063         int d;
1064         int i;
1065         int modified = 0;
1066         unsigned off;
1067
1068         if (!bmap)
1069                 return NULL;
1070
1071         off = 1 + bmap->nparam + bmap->n_in + bmap->n_out;
1072
1073         for (d = bmap->n_div - 1; d >= 0 ; --d) {
1074                 for (i = 0; i < bmap->n_eq; ++i) {
1075                         if (!isl_int_is_one(bmap->eq[i][off + d]) &&
1076                             !isl_int_is_negone(bmap->eq[i][off + d]))
1077                                 continue;
1078                         modified = 1;
1079                         *progress = 1;
1080                         eliminate_div(bmap, bmap->eq[i], d);
1081                         isl_basic_map_drop_equality(bmap, i);
1082                         break;
1083                 }
1084         }
1085         if (modified)
1086                 return eliminate_divs_eq(bmap, progress);
1087         return bmap;
1088 }
1089
1090 static struct isl_basic_map *normalize_constraints(struct isl_basic_map *bmap)
1091 {
1092         int i;
1093         isl_int gcd;
1094         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1095
1096         isl_int_init(gcd);
1097         for (i = bmap->n_eq - 1; i >= 0; --i) {
1098                 isl_seq_gcd(bmap->eq[i]+1, total, &gcd);
1099                 if (isl_int_is_zero(gcd)) {
1100                         if (!isl_int_is_zero(bmap->eq[i][0])) {
1101                                 bmap = isl_basic_map_set_to_empty(bmap);
1102                                 break;
1103                         }
1104                         isl_basic_map_drop_equality(bmap, i);
1105                         continue;
1106                 }
1107                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
1108                         isl_int_gcd(gcd, gcd, bmap->eq[i][0]);
1109                 if (isl_int_is_one(gcd))
1110                         continue;
1111                 if (!isl_int_is_divisible_by(bmap->eq[i][0], gcd)) {
1112                         bmap = isl_basic_map_set_to_empty(bmap);
1113                         break;
1114                 }
1115                 isl_seq_scale_down(bmap->eq[i], bmap->eq[i], gcd, 1+total);
1116         }
1117
1118         for (i = bmap->n_ineq - 1; i >= 0; --i) {
1119                 isl_seq_gcd(bmap->ineq[i]+1, total, &gcd);
1120                 if (isl_int_is_zero(gcd)) {
1121                         if (isl_int_is_neg(bmap->ineq[i][0])) {
1122                                 bmap = isl_basic_map_set_to_empty(bmap);
1123                                 break;
1124                         }
1125                         isl_basic_map_drop_inequality(bmap, i);
1126                         continue;
1127                 }
1128                 if (F_ISSET(bmap, ISL_BASIC_MAP_RATIONAL))
1129                         isl_int_gcd(gcd, gcd, bmap->ineq[i][0]);
1130                 if (isl_int_is_one(gcd))
1131                         continue;
1132                 isl_int_fdiv_q(bmap->ineq[i][0], bmap->ineq[i][0], gcd);
1133                 isl_seq_scale_down(bmap->ineq[i]+1, bmap->ineq[i]+1, gcd, total);
1134         }
1135         isl_int_clear(gcd);
1136
1137         return bmap;
1138 }
1139
1140
1141 /* Eliminate the specified variables from the constraints using
1142  * Fourier-Motzkin.  The variables themselves are not removed.
1143  */
1144 struct isl_basic_map *isl_basic_map_eliminate_vars(
1145         struct isl_basic_map *bmap, int pos, unsigned n)
1146 {
1147         int d;
1148         int i, j, k;
1149         unsigned total;
1150         unsigned extra;
1151
1152         if (!bmap)
1153                 return NULL;
1154         total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1155         extra = bmap->extra - bmap->n_div;
1156
1157         bmap = isl_basic_map_cow(bmap);
1158         bmap = isl_basic_map_gauss(bmap, NULL);
1159         for (d = pos + n - 1; d >= pos; --d) {
1160                 int n_lower, n_upper;
1161                 if (!bmap)
1162                         return NULL;
1163                 for (i = 0; i < bmap->n_eq; ++i) {
1164                         if (isl_int_is_zero(bmap->eq[i][1+d]))
1165                                 continue;
1166                         isl_basic_map_drop_equality(bmap, i);
1167                         break;
1168                 }
1169                 if (i < bmap->n_eq)
1170                         continue;
1171                 n_lower = 0;
1172                 n_upper = 0;
1173                 for (i = 0; i < bmap->n_ineq; ++i) {
1174                         if (isl_int_is_pos(bmap->ineq[i][1+d]))
1175                                 n_lower++;
1176                         else if (isl_int_is_neg(bmap->ineq[i][1+d]))
1177                                 n_upper++;
1178                 }
1179                 bmap = isl_basic_map_extend(bmap,
1180                                 bmap->nparam, bmap->n_in, bmap->n_out, 0,
1181                                 0, n_lower * n_upper);
1182                 for (i = bmap->n_ineq - 1; i >= 0; --i) {
1183                         int last;
1184                         if (isl_int_is_zero(bmap->ineq[i][1+d]))
1185                                 continue;
1186                         last = -1;
1187                         for (j = 0; j < i; ++j) {
1188                                 if (isl_int_is_zero(bmap->ineq[j][1+d]))
1189                                         continue;
1190                                 last = j;
1191                                 if (isl_int_sgn(bmap->ineq[i][1+d]) ==
1192                                     isl_int_sgn(bmap->ineq[j][1+d]))
1193                                         continue;
1194                                 k = isl_basic_map_alloc_inequality(bmap);
1195                                 if (k < 0)
1196                                         goto error;
1197                                 isl_seq_cpy(bmap->ineq[k], bmap->ineq[i],
1198                                                 1+total);
1199                                 isl_seq_clr(bmap->ineq[k]+1+total, extra);
1200                                 isl_seq_elim(bmap->ineq[k], bmap->ineq[j],
1201                                                 1+d, 1+total, NULL);
1202                         }
1203                         isl_basic_map_drop_inequality(bmap, i);
1204                         i = last + 1;
1205                 }
1206                 if (n_lower > 0 && n_upper > 0) {
1207                         bmap = normalize_constraints(bmap);
1208                         bmap = remove_duplicate_constraints(bmap, NULL);
1209                         bmap = isl_basic_map_gauss(bmap, NULL);
1210                         bmap = isl_basic_map_convex_hull(bmap);
1211                         if (!bmap)
1212                                 goto error;
1213                         if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
1214                                 break;
1215                 }
1216         }
1217         return bmap;
1218 error:
1219         isl_basic_map_free(bmap);
1220         return NULL;
1221 }
1222
1223 struct isl_basic_set *isl_basic_set_eliminate_vars(
1224         struct isl_basic_set *bset, unsigned pos, unsigned n)
1225 {
1226         return (struct isl_basic_set *)isl_basic_map_eliminate_vars(
1227                         (struct isl_basic_map *)bset, pos, n);
1228 }
1229
1230 /* Project out n dimensions starting at first using Fourier-Motzkin */
1231 struct isl_set *isl_set_remove_dims(struct isl_set *set,
1232         unsigned first, unsigned n)
1233 {
1234         int i;
1235
1236         if (n == 0)
1237                 return set;
1238
1239         set = isl_set_cow(set);
1240         if (!set)
1241                 return NULL;
1242         isl_assert(set->ctx, first+n <= set->dim, goto error);
1243
1244         for (i = 0; i < set->n; ++i) {
1245                 set->p[i] = isl_basic_set_eliminate_vars(set->p[i],
1246                                                         set->nparam + first, n);
1247                 if (!set->p[i])
1248                         goto error;
1249         }
1250         set = isl_set_drop_dims(set, first, n);
1251         return set;
1252 error:
1253         isl_set_free(set);
1254         return NULL;
1255 }
1256
1257 /* Project out n dimensions starting at first using Fourier-Motzkin */
1258 struct isl_basic_set *isl_basic_set_remove_dims(struct isl_basic_set *bset,
1259         unsigned first, unsigned n)
1260 {
1261         bset = isl_basic_set_eliminate_vars(bset, bset->nparam + first, n);
1262         bset = isl_basic_set_drop_dims(bset, first, n);
1263         return bset;
1264 }
1265
1266 /* Elimininate divs based on inequalities
1267  */
1268 static struct isl_basic_map *eliminate_divs_ineq(
1269                 struct isl_basic_map *bmap, int *progress)
1270 {
1271         int d;
1272         int i;
1273         unsigned off;
1274         struct isl_ctx *ctx;
1275
1276         if (!bmap)
1277                 return NULL;
1278
1279         ctx = bmap->ctx;
1280         off = 1 + bmap->nparam + bmap->n_in + bmap->n_out;
1281
1282         for (d = bmap->n_div - 1; d >= 0 ; --d) {
1283                 for (i = 0; i < bmap->n_eq; ++i)
1284                         if (!isl_int_is_zero(bmap->eq[i][off + d]))
1285                                 break;
1286                 if (i < bmap->n_eq)
1287                         continue;
1288                 for (i = 0; i < bmap->n_ineq; ++i)
1289                         if (isl_int_abs_gt(bmap->ineq[i][off + d], ctx->one))
1290                                 break;
1291                 if (i < bmap->n_ineq)
1292                         continue;
1293                 *progress = 1;
1294                 bmap = isl_basic_map_eliminate_vars(bmap, (off-1)+d, 1);
1295                 if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
1296                         break;
1297                 bmap = isl_basic_map_drop_div(bmap, d);
1298                 if (!bmap)
1299                         break;
1300         }
1301         return bmap;
1302 }
1303
1304 struct isl_basic_map *isl_basic_map_simplify(struct isl_basic_map *bmap)
1305 {
1306         int progress = 1;
1307         if (!bmap)
1308                 return NULL;
1309         while (progress) {
1310                 progress = 0;
1311                 bmap = normalize_constraints(bmap);
1312                 bmap = eliminate_divs_eq(bmap, &progress);
1313                 bmap = eliminate_divs_ineq(bmap, &progress);
1314                 bmap = isl_basic_map_gauss(bmap, &progress);
1315                 bmap = remove_duplicate_divs(bmap, &progress);
1316                 bmap = remove_duplicate_constraints(bmap, &progress);
1317         }
1318         return bmap;
1319 }
1320
1321 struct isl_basic_set *isl_basic_set_simplify(struct isl_basic_set *bset)
1322 {
1323         return (struct isl_basic_set *)
1324                 isl_basic_map_simplify((struct isl_basic_map *)bset);
1325 }
1326
1327 static void dump_term(struct isl_basic_map *bmap,
1328                         isl_int c, int pos, FILE *out)
1329 {
1330         unsigned in = bmap->n_in;
1331         unsigned dim = bmap->n_in + bmap->n_out;
1332         if (!pos)
1333                 isl_int_print(out, c);
1334         else {
1335                 if (!isl_int_is_one(c))
1336                         isl_int_print(out, c);
1337                 if (pos < 1 + bmap->nparam)
1338                         fprintf(out, "p%d", pos - 1);
1339                 else if (pos < 1 + bmap->nparam + in)
1340                         fprintf(out, "i%d", pos - 1 - bmap->nparam);
1341                 else if (pos < 1 + bmap->nparam + dim)
1342                         fprintf(out, "o%d", pos - 1 - bmap->nparam - in);
1343                 else
1344                         fprintf(out, "e%d", pos - 1 - bmap->nparam - dim);
1345         }
1346 }
1347
1348 static void dump_constraint_sign(struct isl_basic_map *bmap, isl_int *c,
1349                                 int sign, FILE *out)
1350 {
1351         int i;
1352         int first;
1353         unsigned len = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1354         isl_int v;
1355
1356         isl_int_init(v);
1357         for (i = 0, first = 1; i < len; ++i) {
1358                 if (isl_int_sgn(c[i]) * sign <= 0)
1359                         continue;
1360                 if (!first)
1361                         fprintf(out, " + ");
1362                 first = 0;
1363                 isl_int_abs(v, c[i]);
1364                 dump_term(bmap, v, i, out);
1365         }
1366         isl_int_clear(v);
1367         if (first)
1368                 fprintf(out, "0");
1369 }
1370
1371 static void dump_constraint(struct isl_basic_map *bmap, isl_int *c,
1372                                 const char *op, FILE *out, int indent)
1373 {
1374         int i;
1375
1376         fprintf(out, "%*s", indent, "");
1377
1378         dump_constraint_sign(bmap, c, 1, out);
1379         fprintf(out, " %s ", op);
1380         dump_constraint_sign(bmap, c, -1, out);
1381
1382         fprintf(out, "\n");
1383
1384         for (i = bmap->n_div; i < bmap->extra; ++i) {
1385                 if (isl_int_is_zero(c[1+bmap->nparam+bmap->n_in+bmap->n_out+i]))
1386                         continue;
1387                 fprintf(out, "%*s", indent, "");
1388                 fprintf(out, "ERROR: unused div coefficient not zero\n");
1389         }
1390 }
1391
1392 static void dump_constraints(struct isl_basic_map *bmap,
1393                                 isl_int **c, unsigned n,
1394                                 const char *op, FILE *out, int indent)
1395 {
1396         int i;
1397
1398         for (i = 0; i < n; ++i)
1399                 dump_constraint(bmap, c[i], op, out, indent);
1400 }
1401
1402 static void dump_affine(struct isl_basic_map *bmap, isl_int *exp, FILE *out)
1403 {
1404         int j;
1405         int first = 1;
1406         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1407
1408         for (j = 0; j < 1 + total; ++j) {
1409                 if (isl_int_is_zero(exp[j]))
1410                         continue;
1411                 if (!first && isl_int_is_pos(exp[j]))
1412                         fprintf(out, "+");
1413                 dump_term(bmap, exp[j], j, out);
1414                 first = 0;
1415         }
1416 }
1417
1418 static void dump(struct isl_basic_map *bmap, FILE *out, int indent)
1419 {
1420         int i;
1421
1422         dump_constraints(bmap, bmap->eq, bmap->n_eq, "=", out, indent);
1423         dump_constraints(bmap, bmap->ineq, bmap->n_ineq, ">=", out, indent);
1424
1425         for (i = 0; i < bmap->n_div; ++i) {
1426                 fprintf(out, "%*s", indent, "");
1427                 fprintf(out, "e%d = [(", i);
1428                 dump_affine(bmap, bmap->div[i]+1, out);
1429                 fprintf(out, ")/");
1430                 isl_int_print(out, bmap->div[i][0]);
1431                 fprintf(out, "]\n");
1432         }
1433 }
1434
1435 void isl_basic_set_dump(struct isl_basic_set *bset, FILE *out, int indent)
1436 {
1437         if (!bset) {
1438                 fprintf(out, "null basic set\n");
1439                 return;
1440         }
1441
1442         fprintf(out, "%*s", indent, "");
1443         fprintf(out, "ref: %d, nparam: %d, dim: %d, extra: %d\n",
1444                         bset->ref, bset->nparam, bset->dim, bset->extra);
1445         dump((struct isl_basic_map *)bset, out, indent);
1446 }
1447
1448 void isl_basic_map_dump(struct isl_basic_map *bmap, FILE *out, int indent)
1449 {
1450         if (!bmap) {
1451                 fprintf(out, "null basic map\n");
1452                 return;
1453         }
1454
1455         fprintf(out, "%*s", indent, "");
1456         fprintf(out, "ref: %d, nparam: %d, in: %d, out: %d, extra: %d, flags: %x\n",
1457                 bmap->ref,
1458                 bmap->nparam, bmap->n_in, bmap->n_out, bmap->extra, bmap->flags);
1459         dump(bmap, out, indent);
1460 }
1461
1462 int isl_inequality_negate(struct isl_basic_map *bmap, unsigned pos)
1463 {
1464         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
1465         if (!bmap)
1466                 return -1;
1467         isl_assert(bmap->ctx, pos < bmap->n_ineq, return -1);
1468         isl_seq_neg(bmap->ineq[pos], bmap->ineq[pos], 1 + total);
1469         isl_int_sub_ui(bmap->ineq[pos][0], bmap->ineq[pos][0], 1);
1470         return 0;
1471 }
1472
1473 struct isl_set *isl_set_alloc(struct isl_ctx *ctx,
1474                 unsigned nparam, unsigned dim, int n, unsigned flags)
1475 {
1476         struct isl_set *set;
1477
1478         isl_assert(ctx, n >= 0, return NULL);
1479         set = isl_alloc(ctx, struct isl_set,
1480                         sizeof(struct isl_set) +
1481                         n * sizeof(struct isl_basic_set *));
1482         if (!set)
1483                 return NULL;
1484
1485         set->ctx = ctx;
1486         isl_ctx_ref(ctx);
1487         set->ref = 1;
1488         set->size = n;
1489         set->n = 0;
1490         set->nparam = nparam;
1491         set->zero = 0;
1492         set->dim = dim;
1493         set->flags = flags;
1494         return set;
1495 }
1496
1497 struct isl_set *isl_set_dup(struct isl_set *set)
1498 {
1499         int i;
1500         struct isl_set *dup;
1501
1502         if (!set)
1503                 return NULL;
1504
1505         dup = isl_set_alloc(set->ctx, set->nparam, set->dim, set->n, set->flags);
1506         if (!dup)
1507                 return NULL;
1508         for (i = 0; i < set->n; ++i)
1509                 dup = isl_set_add(dup,
1510                                   isl_basic_set_dup(set->p[i]));
1511         return dup;
1512 }
1513
1514 struct isl_set *isl_set_from_basic_set(struct isl_basic_set *bset)
1515 {
1516         struct isl_set *set;
1517
1518         if (!bset)
1519                 return NULL;
1520
1521         set = isl_set_alloc(bset->ctx, bset->nparam, bset->dim, 1, ISL_MAP_DISJOINT);
1522         if (!set) {
1523                 isl_basic_set_free(bset);
1524                 return NULL;
1525         }
1526         return isl_set_add(set, bset);
1527 }
1528
1529 struct isl_map *isl_map_from_basic_map(struct isl_basic_map *bmap)
1530 {
1531         struct isl_map *map;
1532
1533         if (!bmap)
1534                 return NULL;
1535
1536         map = isl_map_alloc(bmap->ctx, bmap->nparam, bmap->n_in, bmap->n_out, 1,
1537                                 ISL_MAP_DISJOINT);
1538         if (!map) {
1539                 isl_basic_map_free(bmap);
1540                 return NULL;
1541         }
1542         return isl_map_add(map, bmap);
1543 }
1544
1545 struct isl_set *isl_set_add(struct isl_set *set, struct isl_basic_set *bset)
1546 {
1547         if (!bset || !set)
1548                 goto error;
1549         isl_assert(set->ctx, set->nparam == bset->nparam, goto error);
1550         isl_assert(set->ctx, set->dim == bset->dim, goto error);
1551         isl_assert(set->ctx, set->n < set->size, goto error);
1552         set->p[set->n] = bset;
1553         set->n++;
1554         return set;
1555 error:
1556         if (set)
1557                 isl_set_free(set);
1558         if (bset)
1559                 isl_basic_set_free(bset);
1560         return NULL;
1561 }
1562
1563 void isl_set_free(struct isl_set *set)
1564 {
1565         int i;
1566
1567         if (!set)
1568                 return;
1569
1570         if (--set->ref > 0)
1571                 return;
1572
1573         isl_ctx_deref(set->ctx);
1574         for (i = 0; i < set->n; ++i)
1575                 isl_basic_set_free(set->p[i]);
1576         free(set);
1577 }
1578
1579 void isl_set_dump(struct isl_set *set, FILE *out, int indent)
1580 {
1581         int i;
1582
1583         if (!set) {
1584                 fprintf(out, "null set\n");
1585                 return;
1586         }
1587
1588         fprintf(out, "%*s", indent, "");
1589         fprintf(out, "ref: %d, n: %d, nparam: %d, dim: %d, flags: %x\n",
1590                         set->ref, set->n, set->nparam, set->dim, set->flags);
1591         for (i = 0; i < set->n; ++i) {
1592                 fprintf(out, "%*s", indent, "");
1593                 fprintf(out, "basic set %d:\n", i);
1594                 isl_basic_set_dump(set->p[i], out, indent+4);
1595         }
1596 }
1597
1598 void isl_map_dump(struct isl_map *map, FILE *out, int indent)
1599 {
1600         int i;
1601
1602         if (!map) {
1603                 fprintf(out, "null map\n");
1604                 return;
1605         }
1606
1607         fprintf(out, "%*s", indent, "");
1608         fprintf(out, "ref: %d, n: %d, nparam: %d, in: %d, out: %d, flags: %x\n",
1609                         map->ref, map->n, map->nparam, map->n_in, map->n_out,
1610                         map->flags);
1611         for (i = 0; i < map->n; ++i) {
1612                 fprintf(out, "%*s", indent, "");
1613                 fprintf(out, "basic map %d:\n", i);
1614                 isl_basic_map_dump(map->p[i], out, indent+4);
1615         }
1616 }
1617
1618 struct isl_basic_map *isl_basic_map_intersect_domain(
1619                 struct isl_basic_map *bmap, struct isl_basic_set *bset)
1620 {
1621         struct isl_basic_map *bmap_domain;
1622
1623         if (!bmap || !bset)
1624                 goto error;
1625
1626         isl_assert(bset->ctx, bset->dim == bmap->n_in, goto error);
1627         isl_assert(bset->ctx, bset->nparam == bmap->nparam, goto error);
1628
1629         bmap = isl_basic_map_extend(bmap,
1630                         bset->nparam, bmap->n_in, bmap->n_out,
1631                         bset->n_div, bset->n_eq, bset->n_ineq);
1632         if (!bmap)
1633                 goto error;
1634         bmap_domain = isl_basic_map_from_basic_set(bset,
1635                                                 bset->dim, 0);
1636         bmap = add_constraints(bmap, bmap_domain, 0, 0);
1637
1638         bmap = isl_basic_map_simplify(bmap);
1639         return isl_basic_map_finalize(bmap);
1640 error:
1641         isl_basic_map_free(bmap);
1642         isl_basic_set_free(bset);
1643         return NULL;
1644 }
1645
1646 struct isl_basic_map *isl_basic_map_intersect_range(
1647                 struct isl_basic_map *bmap, struct isl_basic_set *bset)
1648 {
1649         struct isl_basic_map *bmap_range;
1650
1651         if (!bmap || !bset)
1652                 goto error;
1653
1654         isl_assert(bset->ctx, bset->dim == bmap->n_out, goto error);
1655         isl_assert(bset->ctx, bset->nparam == bmap->nparam, goto error);
1656
1657         bmap = isl_basic_map_extend(bmap,
1658                         bset->nparam, bmap->n_in, bmap->n_out,
1659                         bset->n_div, bset->n_eq, bset->n_ineq);
1660         if (!bmap)
1661                 goto error;
1662         bmap_range = isl_basic_map_from_basic_set(bset,
1663                                                 0, bset->dim);
1664         bmap = add_constraints(bmap, bmap_range, 0, 0);
1665
1666         bmap = isl_basic_map_simplify(bmap);
1667         return isl_basic_map_finalize(bmap);
1668 error:
1669         isl_basic_map_free(bmap);
1670         isl_basic_set_free(bset);
1671         return NULL;
1672 }
1673
1674 struct isl_basic_map *isl_basic_map_intersect(
1675                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1676 {
1677         if (!bmap1 || !bmap2)
1678                 goto error;
1679
1680         isl_assert(bmap1->ctx, bmap1->nparam == bmap2->nparam, goto error);
1681         isl_assert(bmap1->ctx, bmap1->n_in == bmap2->n_in, goto error);
1682         isl_assert(bmap1->ctx, bmap1->n_out == bmap2->n_out, goto error);
1683
1684         bmap1 = isl_basic_map_extend(bmap1,
1685                         bmap1->nparam, bmap1->n_in, bmap1->n_out,
1686                         bmap2->n_div, bmap2->n_eq, bmap2->n_ineq);
1687         if (!bmap1)
1688                 goto error;
1689         bmap1 = add_constraints(bmap1, bmap2, 0, 0);
1690
1691         bmap1 = isl_basic_map_simplify(bmap1);
1692         return isl_basic_map_finalize(bmap1);
1693 error:
1694         isl_basic_map_free(bmap1);
1695         isl_basic_map_free(bmap2);
1696         return NULL;
1697 }
1698
1699 struct isl_basic_set *isl_basic_set_intersect(
1700                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
1701 {
1702         return (struct isl_basic_set *)
1703                 isl_basic_map_intersect(
1704                         (struct isl_basic_map *)bset1,
1705                         (struct isl_basic_map *)bset2);
1706 }
1707
1708 struct isl_map *isl_map_intersect(struct isl_map *map1, struct isl_map *map2)
1709 {
1710         unsigned flags = 0;
1711         struct isl_map *result;
1712         int i, j;
1713
1714         if (!map1 || !map2)
1715                 goto error;
1716
1717         if (F_ISSET(map1, ISL_MAP_DISJOINT) &&
1718             F_ISSET(map2, ISL_MAP_DISJOINT))
1719                 FL_SET(flags, ISL_MAP_DISJOINT);
1720
1721         result = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map1->n_out,
1722                                 map1->n * map2->n, flags);
1723         if (!result)
1724                 goto error;
1725         for (i = 0; i < map1->n; ++i)
1726                 for (j = 0; j < map2->n; ++j) {
1727                         struct isl_basic_map *part;
1728                         part = isl_basic_map_intersect(
1729                                     isl_basic_map_copy(map1->p[i]),
1730                                     isl_basic_map_copy(map2->p[j]));
1731                         if (isl_basic_map_is_empty(part))
1732                                 isl_basic_map_free(part);
1733                         else
1734                                 result = isl_map_add(result, part);
1735                         if (!result)
1736                                 goto error;
1737                 }
1738         isl_map_free(map1);
1739         isl_map_free(map2);
1740         return result;
1741 error:
1742         isl_map_free(map1);
1743         isl_map_free(map2);
1744         return NULL;
1745 }
1746
1747 struct isl_set *isl_set_intersect(struct isl_set *set1, struct isl_set *set2)
1748 {
1749         return (struct isl_set *)
1750                 isl_map_intersect((struct isl_map *)set1,
1751                                   (struct isl_map *)set2);
1752 }
1753
1754 struct isl_basic_map *isl_basic_map_reverse(struct isl_basic_map *bmap)
1755 {
1756         struct isl_basic_set *bset;
1757         unsigned in;
1758
1759         if (!bmap)
1760                 return NULL;
1761         bmap = isl_basic_map_cow(bmap);
1762         if (!bmap)
1763                 return NULL;
1764         in = bmap->n_in;
1765         bset = isl_basic_set_from_basic_map(bmap);
1766         bset = isl_basic_set_swap_vars(bset, in);
1767         return isl_basic_map_from_basic_set(bset, bset->dim-in, in);
1768 }
1769
1770 /* Turn final n dimensions into existentially quantified variables.
1771  */
1772 struct isl_basic_set *isl_basic_set_project_out(
1773                 struct isl_basic_set *bset, unsigned n, unsigned flags)
1774 {
1775         int i;
1776         size_t row_size;
1777         isl_int **new_div;
1778         isl_int *old;
1779
1780         if (!bset)
1781                 return NULL;
1782
1783         isl_assert(bset->ctx, n <= bset->dim, goto error);
1784
1785         if (n == 0)
1786                 return bset;
1787
1788         bset = isl_basic_set_cow(bset);
1789
1790         row_size = 1 + bset->nparam + bset->dim + bset->extra;
1791         old = bset->block2.data;
1792         bset->block2 = isl_blk_extend(bset->ctx, bset->block2,
1793                                         (bset->extra + n) * (1 + row_size));
1794         if (!bset->block2.data)
1795                 goto error;
1796         new_div = isl_alloc_array(ctx, isl_int *, bset->extra + n);
1797         if (!new_div)
1798                 goto error;
1799         for (i = 0; i < n; ++i) {
1800                 new_div[i] = bset->block2.data +
1801                                 (bset->extra + i) * (1 + row_size);
1802                 isl_seq_clr(new_div[i], 1 + row_size);
1803         }
1804         for (i = 0; i < bset->extra; ++i)
1805                 new_div[n + i] = bset->block2.data + (bset->div[i] - old);
1806         free(bset->div);
1807         bset->div = new_div;
1808         bset->n_div += n;
1809         bset->extra += n;
1810         bset->dim -= n;
1811         bset = isl_basic_set_simplify(bset);
1812         return isl_basic_set_finalize(bset);
1813 error:
1814         isl_basic_set_free(bset);
1815         return NULL;
1816 }
1817
1818 struct isl_basic_map *isl_basic_map_apply_range(
1819                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1820 {
1821         struct isl_basic_set *bset;
1822         unsigned n_in, n_out;
1823
1824         if (!bmap1 || !bmap2)
1825                 goto error;
1826
1827         isl_assert(bmap->ctx, bmap1->n_out == bmap2->n_in, goto error);
1828         isl_assert(bmap->ctx, bmap1->nparam == bmap2->nparam, goto error);
1829
1830         n_in = bmap1->n_in;
1831         n_out = bmap2->n_out;
1832
1833         bmap2 = isl_basic_map_reverse(bmap2);
1834         if (!bmap2)
1835                 goto error;
1836         bmap1 = isl_basic_map_extend(bmap1, bmap1->nparam,
1837                         bmap1->n_in + bmap2->n_in, bmap1->n_out,
1838                         bmap2->extra, bmap2->n_eq, bmap2->n_ineq);
1839         if (!bmap1)
1840                 goto error;
1841         bmap1 = add_constraints(bmap1, bmap2, bmap1->n_in - bmap2->n_in, 0);
1842         bmap1 = isl_basic_map_simplify(bmap1);
1843         bset = isl_basic_set_from_basic_map(bmap1);
1844         bset = isl_basic_set_project_out(bset,
1845                                                 bset->dim - (n_in + n_out), 0);
1846         return isl_basic_map_from_basic_set(bset, n_in, n_out);
1847 error:
1848         isl_basic_map_free(bmap1);
1849         isl_basic_map_free(bmap2);
1850         return NULL;
1851 }
1852
1853 struct isl_basic_set *isl_basic_set_apply(
1854                 struct isl_basic_set *bset, struct isl_basic_map *bmap)
1855 {
1856         if (!bset || !bmap)
1857                 goto error;
1858
1859         isl_assert(bset->ctx, bset->dim == bmap->n_in, goto error);
1860
1861         return (struct isl_basic_set *)
1862                 isl_basic_map_apply_range((struct isl_basic_map *)bset, bmap);
1863 error:
1864         isl_basic_set_free(bset);
1865         isl_basic_map_free(bmap);
1866         return NULL;
1867 }
1868
1869 struct isl_basic_map *isl_basic_map_apply_domain(
1870                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
1871 {
1872         if (!bmap1 || !bmap2)
1873                 goto error;
1874
1875         isl_assert(ctx, bmap1->n_in == bmap2->n_in, goto error);
1876         isl_assert(ctx, bmap1->nparam == bmap2->nparam, goto error);
1877
1878         bmap1 = isl_basic_map_reverse(bmap1);
1879         bmap1 = isl_basic_map_apply_range(bmap1, bmap2);
1880         return isl_basic_map_reverse(bmap1);
1881 error:
1882         isl_basic_map_free(bmap1);
1883         isl_basic_map_free(bmap2);
1884         return NULL;
1885 }
1886
1887 static struct isl_basic_map *var_equal(struct isl_ctx *ctx,
1888                 struct isl_basic_map *bmap, unsigned pos)
1889 {
1890         int i;
1891         i = isl_basic_map_alloc_equality(bmap);
1892         if (i < 0)
1893                 goto error;
1894         isl_seq_clr(bmap->eq[i],
1895                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1896         isl_int_set_si(bmap->eq[i][1+bmap->nparam+pos], -1);
1897         isl_int_set_si(bmap->eq[i][1+bmap->nparam+bmap->n_in+pos], 1);
1898         return isl_basic_map_finalize(bmap);
1899 error:
1900         isl_basic_map_free(bmap);
1901         return NULL;
1902 }
1903
1904 static struct isl_basic_map *var_more(struct isl_ctx *ctx,
1905                 struct isl_basic_map *bmap, unsigned pos)
1906 {
1907         int i;
1908         i = isl_basic_map_alloc_inequality(bmap);
1909         if (i < 0)
1910                 goto error;
1911         isl_seq_clr(bmap->ineq[i],
1912                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1913         isl_int_set_si(bmap->ineq[i][0], -1);
1914         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+pos], -1);
1915         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+bmap->n_in+pos], 1);
1916         return isl_basic_map_finalize(bmap);
1917 error:
1918         isl_basic_map_free(bmap);
1919         return NULL;
1920 }
1921
1922 static struct isl_basic_map *var_less(struct isl_ctx *ctx,
1923                 struct isl_basic_map *bmap, unsigned pos)
1924 {
1925         int i;
1926         i = isl_basic_map_alloc_inequality(bmap);
1927         if (i < 0)
1928                 goto error;
1929         isl_seq_clr(bmap->ineq[i],
1930                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
1931         isl_int_set_si(bmap->ineq[i][0], -1);
1932         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+pos], 1);
1933         isl_int_set_si(bmap->ineq[i][1+bmap->nparam+bmap->n_in+pos], -1);
1934         return isl_basic_map_finalize(bmap);
1935 error:
1936         isl_basic_map_free(bmap);
1937         return NULL;
1938 }
1939
1940 struct isl_basic_map *isl_basic_map_equal(struct isl_ctx *ctx,
1941                 unsigned nparam, unsigned in, unsigned out, unsigned n_equal)
1942 {
1943         int i;
1944         struct isl_basic_map *bmap;
1945         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, n_equal, 0);
1946         if (!bmap)
1947                 return NULL;
1948         for (i = 0; i < n_equal && bmap; ++i)
1949                 bmap = var_equal(ctx, bmap, i);
1950         return isl_basic_map_finalize(bmap);
1951 }
1952
1953 struct isl_basic_map *isl_basic_map_less_at(struct isl_ctx *ctx,
1954                 unsigned nparam, unsigned in, unsigned out, unsigned pos)
1955 {
1956         int i;
1957         struct isl_basic_map *bmap;
1958         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, pos, 1);
1959         if (!bmap)
1960                 return NULL;
1961         for (i = 0; i < pos && bmap; ++i)
1962                 bmap = var_equal(ctx, bmap, i);
1963         if (bmap)
1964                 bmap = var_less(ctx, bmap, pos);
1965         return isl_basic_map_finalize(bmap);
1966 }
1967
1968 struct isl_basic_map *isl_basic_map_more_at(struct isl_ctx *ctx,
1969                 unsigned nparam, unsigned in, unsigned out, unsigned pos)
1970 {
1971         int i;
1972         struct isl_basic_map *bmap;
1973         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, pos, 1);
1974         if (!bmap)
1975                 return NULL;
1976         for (i = 0; i < pos && bmap; ++i)
1977                 bmap = var_equal(ctx, bmap, i);
1978         if (bmap)
1979                 bmap = var_more(ctx, bmap, pos);
1980         return isl_basic_map_finalize(bmap);
1981 }
1982
1983 struct isl_basic_map *isl_basic_map_from_basic_set(
1984                 struct isl_basic_set *bset, unsigned n_in, unsigned n_out)
1985 {
1986         struct isl_basic_map *bmap;
1987
1988         bset = isl_basic_set_cow(bset);
1989         if (!bset)
1990                 return NULL;
1991
1992         isl_assert(ctx, bset->dim == n_in + n_out, goto error);
1993         bmap = (struct isl_basic_map *) bset;
1994         bmap->n_in = n_in;
1995         bmap->n_out = n_out;
1996         return isl_basic_map_finalize(bmap);
1997 error:
1998         isl_basic_set_free(bset);
1999         return NULL;
2000 }
2001
2002 struct isl_basic_set *isl_basic_set_from_basic_map(struct isl_basic_map *bmap)
2003 {
2004         if (!bmap)
2005                 goto error;
2006         if (bmap->n_in == 0)
2007                 return (struct isl_basic_set *)bmap;
2008         bmap = isl_basic_map_cow(bmap);
2009         if (!bmap)
2010                 goto error;
2011         bmap->n_out += bmap->n_in;
2012         bmap->n_in = 0;
2013         bmap = isl_basic_map_finalize(bmap);
2014         return (struct isl_basic_set *)bmap;
2015 error:
2016         return NULL;
2017 }
2018
2019 /* For a div d = floor(f/m), add the constraints
2020  *
2021  *              f - m d >= 0
2022  *              -(f-(n-1)) + m d >= 0
2023  *
2024  * Note that the second constraint is the negation of
2025  *
2026  *              f - m d >= n
2027  */
2028 static int add_div_constraints(struct isl_basic_map *bmap, unsigned div)
2029 {
2030         int i, j;
2031         unsigned div_pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
2032         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra;
2033
2034         i = isl_basic_map_alloc_inequality(bmap);
2035         if (i < 0)
2036                 return -1;
2037         isl_seq_cpy(bmap->ineq[i], bmap->div[div]+1, 1+total);
2038         isl_int_neg(bmap->ineq[i][div_pos], bmap->div[div][0]);
2039
2040         j = isl_basic_map_alloc_inequality(bmap);
2041         if (j < 0)
2042                 return -1;
2043         isl_seq_neg(bmap->ineq[j], bmap->ineq[i], 1 + total);
2044         isl_int_add(bmap->ineq[j][0], bmap->ineq[j][0], bmap->ineq[j][div_pos]);
2045         isl_int_sub_ui(bmap->ineq[j][0], bmap->ineq[j][0], 1);
2046         return j;
2047 }
2048
2049 struct isl_basic_set *isl_basic_map_underlying_set(
2050                 struct isl_basic_map *bmap)
2051 {
2052         if (!bmap)
2053                 goto error;
2054         if (bmap->nparam == 0 && bmap->n_in == 0 && bmap->n_div == 0)
2055                 return (struct isl_basic_set *)bmap;
2056         bmap = isl_basic_map_cow(bmap);
2057         if (!bmap)
2058                 goto error;
2059         bmap->n_out += bmap->nparam + bmap->n_in + bmap->n_div;
2060         bmap->nparam = 0;
2061         bmap->n_in = 0;
2062         bmap->extra -= bmap->n_div;
2063         bmap->n_div = 0;
2064         bmap = isl_basic_map_finalize(bmap);
2065         return (struct isl_basic_set *)bmap;
2066 error:
2067         return NULL;
2068 }
2069
2070 struct isl_basic_map *isl_basic_map_overlying_set(
2071         struct isl_basic_set *bset, struct isl_basic_map *like)
2072 {
2073         struct isl_basic_map *bmap;
2074         struct isl_ctx *ctx;
2075         unsigned total;
2076         int i, k;
2077
2078         if (!bset || !like)
2079                 goto error;
2080         ctx = bset->ctx;
2081         isl_assert(ctx, bset->dim ==
2082                         like->nparam + like->n_in + like->n_out + like->n_div,
2083                         goto error);
2084         if (like->nparam == 0 && like->n_in == 0 && like->n_div == 0) {
2085                 isl_basic_map_free(like);
2086                 return (struct isl_basic_map *)bset;
2087         }
2088         bset = isl_basic_set_cow(bset);
2089         if (!bset)
2090                 goto error;
2091         total = bset->dim + bset->extra;
2092         bmap = (struct isl_basic_map *)bset;
2093         bmap->nparam = like->nparam;
2094         bmap->n_in = like->n_in;
2095         bmap->n_out = like->n_out;
2096         bmap->extra += like->n_div;
2097         if (bmap->extra) {
2098                 unsigned ltotal;
2099                 ltotal = total - bmap->extra + like->extra;
2100                 if (ltotal > total)
2101                         ltotal = total;
2102                 bmap->block2 = isl_blk_extend(ctx, bmap->block2,
2103                                         bmap->extra * (1 + 1 + total));
2104                 if (isl_blk_is_error(bmap->block2))
2105                         goto error;
2106                 bmap->div = isl_realloc_array(ctx, bmap->div, isl_int *,
2107                                                 bmap->extra);
2108                 if (!bmap->div)
2109                         goto error;
2110                 bmap = isl_basic_map_extend(bmap, bmap->nparam,
2111                         bmap->n_in, bmap->n_out, 0, 0, 2 * like->n_div);
2112                 for (i = 0; i < like->n_div; ++i) {
2113                         k = isl_basic_map_alloc_div(bmap);
2114                         if (k < 0)
2115                                 goto error;
2116                         isl_seq_cpy(bmap->div[k], like->div[i], 1 + 1 + ltotal);
2117                         isl_seq_clr(bmap->div[k]+1+1+ltotal, total - ltotal);
2118                         if (add_div_constraints(bmap, k) < 0)
2119                                 goto error;
2120                 }
2121         }
2122         isl_basic_map_free(like);
2123         bmap = isl_basic_map_finalize(bmap);
2124         return bmap;
2125 error:
2126         isl_basic_map_free(like);
2127         isl_basic_set_free(bset);
2128         return NULL;
2129 }
2130
2131 struct isl_basic_set *isl_basic_set_from_underlying_set(
2132         struct isl_basic_set *bset, struct isl_basic_set *like)
2133 {
2134         return (struct isl_basic_set *)
2135                 isl_basic_map_overlying_set(bset, (struct isl_basic_map *)like);
2136 }
2137
2138 struct isl_set *isl_set_from_underlying_set(
2139         struct isl_set *set, struct isl_basic_set *like)
2140 {
2141         int i;
2142
2143         if (!set || !like)
2144                 goto error;
2145         isl_assert(set->ctx, set->dim == like->nparam + like->dim + like->n_div,
2146                     goto error);
2147         if (like->nparam == 0 && like->n_div == 0) {
2148                 isl_basic_set_free(like);
2149                 return set;
2150         }
2151         set = isl_set_cow(set);
2152         if (!set)
2153                 goto error;
2154         for (i = 0; i < set->n; ++i) {
2155                 set->p[i] = isl_basic_set_from_underlying_set(set->p[i],
2156                                                       isl_basic_set_copy(like));
2157                 if (!set->p[i])
2158                         goto error;
2159         }
2160         set->nparam = like->nparam;
2161         set->dim = like->dim;
2162         isl_basic_set_free(like);
2163         return set;
2164 error:
2165         isl_basic_set_free(like);
2166         isl_set_free(set);
2167         return NULL;
2168 }
2169
2170 struct isl_set *isl_map_underlying_set(struct isl_map *map)
2171 {
2172         int i;
2173
2174         map = isl_map_align_divs(map);
2175         map = isl_map_cow(map);
2176         if (!map)
2177                 return NULL;
2178
2179         for (i = 0; i < map->n; ++i) {
2180                 map->p[i] = (struct isl_basic_map *)
2181                                 isl_basic_map_underlying_set(map->p[i]);
2182                 if (!map->p[i])
2183                         goto error;
2184         }
2185         if (map->n == 0)
2186                 map->n_out += map->nparam + map->n_in;
2187         else
2188                 map->n_out = map->p[0]->n_out;
2189         map->nparam = 0;
2190         map->n_in = 0;
2191         return (struct isl_set *)map;
2192 error:
2193         isl_map_free(map);
2194         return NULL;
2195 }
2196
2197 struct isl_set *isl_set_to_underlying_set(struct isl_set *set)
2198 {
2199         return (struct isl_set *)isl_map_underlying_set((struct isl_map *)set);
2200 }
2201
2202 struct isl_basic_set *isl_basic_map_domain(struct isl_basic_map *bmap)
2203 {
2204         struct isl_basic_set *domain;
2205         unsigned n_out;
2206         if (!bmap)
2207                 return NULL;
2208         n_out = bmap->n_out;
2209         domain = isl_basic_set_from_basic_map(bmap);
2210         return isl_basic_set_project_out(domain, n_out, 0);
2211 }
2212
2213 struct isl_basic_set *isl_basic_map_range(struct isl_basic_map *bmap)
2214 {
2215         return isl_basic_map_domain(isl_basic_map_reverse(bmap));
2216 }
2217
2218 struct isl_set *isl_map_range(struct isl_map *map)
2219 {
2220         int i;
2221         struct isl_set *set;
2222
2223         if (!map)
2224                 goto error;
2225         map = isl_map_cow(map);
2226         if (!map)
2227                 goto error;
2228
2229         set = (struct isl_set *) map;
2230         set->zero = 0;
2231         for (i = 0; i < map->n; ++i) {
2232                 set->p[i] = isl_basic_map_range(map->p[i]);
2233                 if (!set->p[i])
2234                         goto error;
2235         }
2236         F_CLR(set, ISL_MAP_DISJOINT);
2237         return set;
2238 error:
2239         isl_map_free(map);
2240         return NULL;
2241 }
2242
2243 struct isl_map *isl_map_from_set(struct isl_set *set,
2244                 unsigned n_in, unsigned n_out)
2245 {
2246         int i;
2247         struct isl_map *map = NULL;
2248
2249         if (!set)
2250                 return NULL;
2251         isl_assert(set->ctx, set->dim == n_in + n_out, goto error);
2252         set = isl_set_cow(set);
2253         if (!set)
2254                 return NULL;
2255         map = (struct isl_map *)set;
2256         for (i = 0; i < set->n; ++i) {
2257                 map->p[i] = isl_basic_map_from_basic_set(
2258                                 set->p[i], n_in, n_out);
2259                 if (!map->p[i])
2260                         goto error;
2261         }
2262         map->n_in = n_in;
2263         map->n_out = n_out;
2264         return map;
2265 error:
2266         isl_set_free(set);
2267         return NULL;
2268 }
2269
2270 struct isl_set *isl_set_from_map(struct isl_map *map)
2271 {
2272         int i;
2273         struct isl_set *set = NULL;
2274
2275         if (!map)
2276                 return NULL;
2277         map = isl_map_cow(map);
2278         if (!map)
2279                 return NULL;
2280         map->n_out += map->n_in;
2281         map->n_in = 0;
2282         set = (struct isl_set *)map;
2283         for (i = 0; i < map->n; ++i) {
2284                 set->p[i] = isl_basic_set_from_basic_map(map->p[i]);
2285                 if (!set->p[i])
2286                         goto error;
2287         }
2288         return set;
2289 error:
2290         isl_map_free(map);
2291         return NULL;
2292 }
2293
2294 struct isl_map *isl_map_alloc(struct isl_ctx *ctx,
2295                 unsigned nparam, unsigned in, unsigned out, int n,
2296                 unsigned flags)
2297 {
2298         struct isl_map *map;
2299
2300         map = isl_alloc(ctx, struct isl_map,
2301                         sizeof(struct isl_map) +
2302                         n * sizeof(struct isl_basic_map *));
2303         if (!map)
2304                 return NULL;
2305
2306         map->ctx = ctx;
2307         isl_ctx_ref(ctx);
2308         map->ref = 1;
2309         map->size = n;
2310         map->n = 0;
2311         map->nparam = nparam;
2312         map->n_in = in;
2313         map->n_out = out;
2314         map->flags = flags;
2315         return map;
2316 }
2317
2318 struct isl_basic_map *isl_basic_map_empty(struct isl_ctx *ctx,
2319                 unsigned nparam, unsigned in, unsigned out)
2320 {
2321         struct isl_basic_map *bmap;
2322         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, 1, 0);
2323         bmap = isl_basic_map_set_to_empty(bmap);
2324         return bmap;
2325 }
2326
2327 struct isl_basic_set *isl_basic_set_empty(struct isl_ctx *ctx,
2328                 unsigned nparam, unsigned dim)
2329 {
2330         struct isl_basic_set *bset;
2331         bset = isl_basic_set_alloc(ctx, nparam, dim, 0, 1, 0);
2332         bset = isl_basic_set_set_to_empty(bset);
2333         return bset;
2334 }
2335
2336 struct isl_basic_map *isl_basic_map_universe(struct isl_ctx *ctx,
2337                 unsigned nparam, unsigned in, unsigned out)
2338 {
2339         struct isl_basic_map *bmap;
2340         bmap = isl_basic_map_alloc(ctx, nparam, in, out, 0, 0, 0);
2341         return bmap;
2342 }
2343
2344 struct isl_basic_set *isl_basic_set_universe(struct isl_ctx *ctx,
2345                 unsigned nparam, unsigned dim)
2346 {
2347         struct isl_basic_set *bset;
2348         bset = isl_basic_set_alloc(ctx, nparam, dim, 0, 0, 0);
2349         return bset;
2350 }
2351
2352 struct isl_map *isl_map_empty(struct isl_ctx *ctx,
2353                 unsigned nparam, unsigned in, unsigned out)
2354 {
2355         return isl_map_alloc(ctx, nparam, in, out, 0, ISL_MAP_DISJOINT);
2356 }
2357
2358 struct isl_set *isl_set_empty(struct isl_ctx *ctx,
2359                 unsigned nparam, unsigned dim)
2360 {
2361         return isl_set_alloc(ctx, nparam, dim, 0, ISL_MAP_DISJOINT);
2362 }
2363
2364 struct isl_map *isl_map_dup(struct isl_map *map)
2365 {
2366         int i;
2367         struct isl_map *dup;
2368
2369         if (!map)
2370                 return NULL;
2371         dup = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out, map->n,
2372                                 map->flags);
2373         for (i = 0; i < map->n; ++i)
2374                 dup = isl_map_add(dup,
2375                                   isl_basic_map_dup(map->p[i]));
2376         return dup;
2377 }
2378
2379 struct isl_map *isl_map_add(struct isl_map *map, struct isl_basic_map *bmap)
2380 {
2381         if (!bmap || !map)
2382                 goto error;
2383         isl_assert(map->ctx, map->nparam == bmap->nparam, goto error);
2384         isl_assert(map->ctx, map->n_in == bmap->n_in, goto error);
2385         isl_assert(map->ctx, map->n_out == bmap->n_out, goto error);
2386         isl_assert(map->ctx, map->n < map->size, goto error);
2387         map->p[map->n] = bmap;
2388         map->n++;
2389         return map;
2390 error:
2391         if (map)
2392                 isl_map_free(map);
2393         if (bmap)
2394                 isl_basic_map_free(bmap);
2395         return NULL;
2396 }
2397
2398 void isl_map_free(struct isl_map *map)
2399 {
2400         int i;
2401
2402         if (!map)
2403                 return;
2404
2405         if (--map->ref > 0)
2406                 return;
2407
2408         isl_ctx_deref(map->ctx);
2409         for (i = 0; i < map->n; ++i)
2410                 isl_basic_map_free(map->p[i]);
2411         free(map);
2412 }
2413
2414 struct isl_map *isl_map_extend(struct isl_map *base,
2415                 unsigned nparam, unsigned n_in, unsigned n_out)
2416 {
2417         int i;
2418
2419         base = isl_map_cow(base);
2420         if (!base)
2421                 return NULL;
2422
2423         isl_assert(base->ctx, base->nparam <= nparam, goto error);
2424         isl_assert(base->ctx, base->n_in <= n_in, goto error);
2425         isl_assert(base->ctx, base->n_out <= n_out, goto error);
2426         base->nparam = nparam;
2427         base->n_in = n_in;
2428         base->n_out = n_out;
2429         for (i = 0; i < base->n; ++i) {
2430                 base->p[i] = isl_basic_map_extend(base->p[i],
2431                                 nparam, n_in, n_out, 0, 0, 0);
2432                 if (!base->p[i])
2433                         goto error;
2434         }
2435         return base;
2436 error:
2437         isl_map_free(base);
2438         return NULL;
2439 }
2440
2441 struct isl_set *isl_set_extend(struct isl_set *base,
2442                 unsigned nparam, unsigned dim)
2443 {
2444         return (struct isl_set *)isl_map_extend((struct isl_map *)base,
2445                                                         nparam, 0, dim);
2446 }
2447
2448 static struct isl_basic_map *isl_basic_map_fix_var(struct isl_basic_map *bmap,
2449                 unsigned var, int value)
2450 {
2451         int j;
2452
2453         bmap = isl_basic_map_cow(bmap);
2454         bmap = isl_basic_map_extend(bmap,
2455                         bmap->nparam, bmap->n_in, bmap->n_out, 0, 1, 0);
2456         j = isl_basic_map_alloc_equality(bmap);
2457         if (j < 0)
2458                 goto error;
2459         isl_seq_clr(bmap->eq[j],
2460                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
2461         isl_int_set_si(bmap->eq[j][1 + var], -1);
2462         isl_int_set_si(bmap->eq[j][0], value);
2463         bmap = isl_basic_map_simplify(bmap);
2464         return isl_basic_map_finalize(bmap);
2465 error:
2466         isl_basic_map_free(bmap);
2467         return NULL;
2468 }
2469
2470 struct isl_basic_map *isl_basic_map_fix_input_si(struct isl_basic_map *bmap,
2471                 unsigned input, int value)
2472 {
2473         if (!bmap)
2474                 return NULL;
2475         isl_assert(bmap->ctx, input < bmap->n_in, goto error);
2476         return isl_basic_map_fix_var(bmap, bmap->nparam + input, value);
2477 error:
2478         isl_basic_map_free(bmap);
2479         return NULL;
2480 }
2481
2482 struct isl_basic_set *isl_basic_set_fix_dim_si(struct isl_basic_set *bset,
2483                 unsigned dim, int value)
2484 {
2485         if (!bset)
2486                 return NULL;
2487         isl_assert(bset->ctx, dim < bset->dim, goto error);
2488         return (struct isl_basic_set *)
2489                 isl_basic_map_fix_var((struct isl_basic_map *)bset,
2490                                                 bset->nparam + dim, value);
2491 error:
2492         isl_basic_set_free(bset);
2493         return NULL;
2494 }
2495
2496 struct isl_map *isl_map_fix_input_si(struct isl_map *map,
2497                 unsigned input, int value)
2498 {
2499         int i;
2500
2501         map = isl_map_cow(map);
2502         if (!map)
2503                 return NULL;
2504
2505         isl_assert(ctx, input < map->n_in, goto error);
2506         for (i = 0; i < map->n; ++i) {
2507                 map->p[i] = isl_basic_map_fix_input_si(map->p[i], input, value);
2508                 if (!map->p[i])
2509                         goto error;
2510         }
2511         return map;
2512 error:
2513         isl_map_free(map);
2514         return NULL;
2515 }
2516
2517 struct isl_set *isl_set_fix_dim_si(struct isl_set *set, unsigned dim, int value)
2518 {
2519         int i;
2520
2521         set = isl_set_cow(set);
2522         if (!set)
2523                 return NULL;
2524
2525         isl_assert(set->ctx, dim < set->dim, goto error);
2526         for (i = 0; i < set->n; ++i) {
2527                 set->p[i] = isl_basic_set_fix_dim_si(set->p[i], dim, value);
2528                 if (!set->p[i])
2529                         goto error;
2530         }
2531         return set;
2532 error:
2533         isl_set_free(set);
2534         return NULL;
2535 }
2536
2537 struct isl_map *isl_map_reverse(struct isl_map *map)
2538 {
2539         int i;
2540         unsigned t;
2541
2542         map = isl_map_cow(map);
2543         if (!map)
2544                 return NULL;
2545
2546         t = map->n_in;
2547         map->n_in = map->n_out;
2548         map->n_out = t;
2549         for (i = 0; i < map->n; ++i) {
2550                 map->p[i] = isl_basic_map_reverse(map->p[i]);
2551                 if (!map->p[i])
2552                         goto error;
2553         }
2554         return map;
2555 error:
2556         isl_map_free(map);
2557         return NULL;
2558 }
2559
2560 struct isl_map *isl_basic_map_lexmax(
2561                 struct isl_basic_map *bmap, struct isl_basic_set *dom,
2562                 struct isl_set **empty)
2563 {
2564         return isl_pip_basic_map_lexmax(bmap, dom, empty);
2565 }
2566
2567 struct isl_map *isl_basic_map_lexmin(
2568                 struct isl_basic_map *bmap, struct isl_basic_set *dom,
2569                 struct isl_set **empty)
2570 {
2571         return isl_pip_basic_map_lexmin(bmap, dom, empty);
2572 }
2573
2574 struct isl_set *isl_basic_set_lexmin(struct isl_basic_set *bset)
2575 {
2576         struct isl_basic_map *bmap = NULL;
2577         struct isl_basic_set *dom = NULL;
2578         struct isl_map *min;
2579
2580         if (!bset)
2581                 goto error;
2582         bmap = isl_basic_map_from_basic_set(bset, 0, bset->dim);
2583         if (!bmap)
2584                 goto error;
2585         dom = isl_basic_set_alloc(bmap->ctx, bmap->nparam, 0, 0, 0, 0);
2586         if (!dom)
2587                 goto error;
2588         min = isl_basic_map_lexmin(bmap, dom, NULL);
2589         return isl_map_range(min);
2590 error:
2591         isl_basic_map_free(bmap);
2592         return NULL;
2593 }
2594
2595 struct isl_map *isl_basic_map_compute_divs(struct isl_basic_map *bmap)
2596 {
2597         if (!bmap)
2598                 return NULL;
2599         if (bmap->n_div == 0)
2600                 return isl_map_from_basic_map(bmap);
2601         return isl_pip_basic_map_compute_divs(bmap);
2602 }
2603
2604 struct isl_map *isl_map_compute_divs(struct isl_map *map)
2605 {
2606         int i;
2607         struct isl_map *res;
2608
2609         if (!map)
2610                 return NULL;
2611         if (map->n == 0)
2612                 return map;
2613         res = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[0]));
2614         for (i = 1 ; i < map->n; ++i) {
2615                 struct isl_map *r2;
2616                 r2 = isl_basic_map_compute_divs(isl_basic_map_copy(map->p[i]));
2617                 if (F_ISSET(map, ISL_MAP_DISJOINT))
2618                         res = isl_map_union_disjoint(res, r2);
2619                 else
2620                         res = isl_map_union(res, r2);
2621         }
2622         isl_map_free(map);
2623
2624         return res;
2625 }
2626
2627 struct isl_set *isl_basic_set_compute_divs(struct isl_basic_set *bset)
2628 {
2629         return (struct isl_set *)
2630                 isl_basic_map_compute_divs((struct isl_basic_map *)bset);
2631 }
2632
2633 struct isl_set *isl_set_compute_divs(struct isl_set *set)
2634 {
2635         return (struct isl_set *)
2636                 isl_map_compute_divs((struct isl_map *)set);
2637 }
2638
2639 struct isl_set *isl_map_domain(struct isl_map *map)
2640 {
2641         int i;
2642         struct isl_set *set;
2643
2644         if (!map)
2645                 goto error;
2646
2647         map = isl_map_cow(map);
2648         if (!map)
2649                 return NULL;
2650
2651         set = (struct isl_set *)map;
2652         set->dim = map->n_in;
2653         set->zero = 0;
2654         for (i = 0; i < map->n; ++i) {
2655                 set->p[i] = isl_basic_map_domain(map->p[i]);
2656                 if (!set->p[i])
2657                         goto error;
2658         }
2659         F_CLR(set, ISL_MAP_DISJOINT);
2660         return set;
2661 error:
2662         isl_map_free(map);
2663         return NULL;
2664 }
2665
2666 struct isl_map *isl_map_union_disjoint(
2667                         struct isl_map *map1, struct isl_map *map2)
2668 {
2669         int i;
2670         unsigned flags = 0;
2671         struct isl_map *map = NULL;
2672
2673         if (!map1 || !map2)
2674                 goto error;
2675
2676         if (map1->n == 0) {
2677                 isl_map_free(map1);
2678                 return map2;
2679         }
2680         if (map2->n == 0) {
2681                 isl_map_free(map2);
2682                 return map1;
2683         }
2684
2685         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
2686         isl_assert(map1->ctx, map1->n_in == map2->n_in, goto error);
2687         isl_assert(map1->ctx, map1->n_out == map2->n_out, goto error);
2688
2689         if (F_ISSET(map1, ISL_MAP_DISJOINT) &&
2690             F_ISSET(map2, ISL_MAP_DISJOINT))
2691                 FL_SET(flags, ISL_MAP_DISJOINT);
2692
2693         map = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map1->n_out,
2694                                 map1->n + map2->n, flags);
2695         if (!map)
2696                 goto error;
2697         for (i = 0; i < map1->n; ++i) {
2698                 map = isl_map_add(map,
2699                                   isl_basic_map_copy(map1->p[i]));
2700                 if (!map)
2701                         goto error;
2702         }
2703         for (i = 0; i < map2->n; ++i) {
2704                 map = isl_map_add(map,
2705                                   isl_basic_map_copy(map2->p[i]));
2706                 if (!map)
2707                         goto error;
2708         }
2709         isl_map_free(map1);
2710         isl_map_free(map2);
2711         return map;
2712 error:
2713         isl_map_free(map);
2714         isl_map_free(map1);
2715         isl_map_free(map2);
2716         return NULL;
2717 }
2718
2719 struct isl_map *isl_map_union(struct isl_map *map1, struct isl_map *map2)
2720 {
2721         map1 = isl_map_union_disjoint(map1, map2);
2722         if (!map1)
2723                 return NULL;
2724         if (map1->n > 1)
2725                 F_CLR(map1, ISL_MAP_DISJOINT);
2726         return map1;
2727 }
2728
2729 struct isl_set *isl_set_union_disjoint(
2730                         struct isl_set *set1, struct isl_set *set2)
2731 {
2732         return (struct isl_set *)
2733                 isl_map_union_disjoint(
2734                         (struct isl_map *)set1, (struct isl_map *)set2);
2735 }
2736
2737 struct isl_set *isl_set_union(struct isl_set *set1, struct isl_set *set2)
2738 {
2739         return (struct isl_set *)
2740                 isl_map_union((struct isl_map *)set1, (struct isl_map *)set2);
2741 }
2742
2743 struct isl_map *isl_map_intersect_range(
2744                 struct isl_map *map, struct isl_set *set)
2745 {
2746         unsigned flags = 0;
2747         struct isl_map *result;
2748         int i, j;
2749
2750         if (!map || !set)
2751                 goto error;
2752
2753         if (F_ISSET(map, ISL_MAP_DISJOINT) &&
2754             F_ISSET(set, ISL_MAP_DISJOINT))
2755                 FL_SET(flags, ISL_MAP_DISJOINT);
2756
2757         result = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out,
2758                                 map->n * set->n, flags);
2759         if (!result)
2760                 goto error;
2761         for (i = 0; i < map->n; ++i)
2762                 for (j = 0; j < set->n; ++j) {
2763                         result = isl_map_add(result,
2764                             isl_basic_map_intersect_range(
2765                                 isl_basic_map_copy(map->p[i]),
2766                                 isl_basic_set_copy(set->p[j])));
2767                         if (!result)
2768                                 goto error;
2769                 }
2770         isl_map_free(map);
2771         isl_set_free(set);
2772         return result;
2773 error:
2774         isl_map_free(map);
2775         isl_set_free(set);
2776         return NULL;
2777 }
2778
2779 struct isl_map *isl_map_intersect_domain(
2780                 struct isl_map *map, struct isl_set *set)
2781 {
2782         return isl_map_reverse(
2783                 isl_map_intersect_range(isl_map_reverse(map), set));
2784 }
2785
2786 struct isl_map *isl_map_apply_domain(
2787                 struct isl_map *map1, struct isl_map *map2)
2788 {
2789         if (!map1 || !map2)
2790                 goto error;
2791         map1 = isl_map_reverse(map1);
2792         map1 = isl_map_apply_range(map1, map2);
2793         return isl_map_reverse(map1);
2794 error:
2795         isl_map_free(map1);
2796         isl_map_free(map2);
2797         return NULL;
2798 }
2799
2800 struct isl_map *isl_map_apply_range(
2801                 struct isl_map *map1, struct isl_map *map2)
2802 {
2803         struct isl_map *result;
2804         int i, j;
2805
2806         if (!map1 || !map2)
2807                 goto error;
2808
2809         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
2810         isl_assert(map1->ctx, map1->n_out == map2->n_in, goto error);
2811
2812         result = isl_map_alloc(map1->ctx, map1->nparam, map1->n_in, map2->n_out,
2813                                 map1->n * map2->n, 0);
2814         if (!result)
2815                 goto error;
2816         for (i = 0; i < map1->n; ++i)
2817                 for (j = 0; j < map2->n; ++j) {
2818                         result = isl_map_add(result,
2819                             isl_basic_map_apply_range(
2820                                 isl_basic_map_copy(map1->p[i]),
2821                                 isl_basic_map_copy(map2->p[j])));
2822                         if (!result)
2823                                 goto error;
2824                 }
2825         isl_map_free(map1);
2826         isl_map_free(map2);
2827         if (result && result->n <= 1)
2828                 F_SET(result, ISL_MAP_DISJOINT);
2829         return result;
2830 error:
2831         isl_map_free(map1);
2832         isl_map_free(map2);
2833         return NULL;
2834 }
2835
2836 /*
2837  * returns range - domain
2838  */
2839 struct isl_basic_set *isl_basic_map_deltas(struct isl_basic_map *bmap)
2840 {
2841         struct isl_basic_set *bset;
2842         unsigned dim;
2843         int i;
2844
2845         if (!bmap)
2846                 goto error;
2847         isl_assert(bmap->ctx, bmap->n_in == bmap->n_out, goto error);
2848         dim = bmap->n_in;
2849         bset = isl_basic_set_from_basic_map(bmap);
2850         bset = isl_basic_set_extend(bset, bset->nparam, 3*dim, 0,
2851                                         dim, 0);
2852         bset = isl_basic_set_swap_vars(bset, 2*dim);
2853         for (i = 0; i < dim; ++i) {
2854                 int j = isl_basic_map_alloc_equality(
2855                                             (struct isl_basic_map *)bset);
2856                 if (j < 0)
2857                         goto error;
2858                 isl_seq_clr(bset->eq[j],
2859                             1 + bset->nparam + bset->dim + bset->extra);
2860                 isl_int_set_si(bset->eq[j][1+bset->nparam+i], 1);
2861                 isl_int_set_si(bset->eq[j][1+bset->nparam+dim+i], 1);
2862                 isl_int_set_si(bset->eq[j][1+bset->nparam+2*dim+i], -1);
2863         }
2864         return isl_basic_set_project_out(bset, 2*dim, 0);
2865 error:
2866         isl_basic_map_free(bmap);
2867         return NULL;
2868 }
2869
2870 /* If the only constraints a div d=floor(f/m)
2871  * appears in are its two defining constraints
2872  *
2873  *      f - m d >=0
2874  *      -(f - (m - 1)) + m d >= 0
2875  *
2876  * then it can safely be removed.
2877  */
2878 static int div_is_redundant(struct isl_basic_map *bmap, int div)
2879 {
2880         int i;
2881         unsigned pos = 1 + bmap->nparam + bmap->n_in + bmap->n_out + div;
2882
2883         for (i = 0; i < bmap->n_eq; ++i)
2884                 if (!isl_int_is_zero(bmap->eq[i][pos]))
2885                         return 0;
2886
2887         for (i = 0; i < bmap->n_ineq; ++i) {
2888                 if (isl_int_is_zero(bmap->ineq[i][pos]))
2889                         continue;
2890                 if (isl_int_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
2891                         int neg;
2892                         isl_int_sub(bmap->div[div][1],
2893                                         bmap->div[div][1], bmap->div[div][0]);
2894                         isl_int_add_ui(bmap->div[div][1], bmap->div[div][1], 1);
2895                         neg = isl_seq_is_neg(bmap->ineq[i], bmap->div[div]+1, pos);
2896                         isl_int_sub_ui(bmap->div[div][1], bmap->div[div][1], 1);
2897                         isl_int_add(bmap->div[div][1],
2898                                         bmap->div[div][1], bmap->div[div][0]);
2899                         if (!neg)
2900                                 return 0;
2901                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
2902                                                     bmap->n_div-div-1) != -1)
2903                                 return 0;
2904                 } else if (isl_int_abs_eq(bmap->ineq[i][pos], bmap->div[div][0])) {
2905                         if (!isl_seq_eq(bmap->ineq[i], bmap->div[div]+1, pos))
2906                                 return 0;
2907                         if (isl_seq_first_non_zero(bmap->ineq[i]+pos+1,
2908                                                     bmap->n_div-div-1) != -1)
2909                                 return 0;
2910                 } else
2911                         return 0;
2912         }
2913
2914         for (i = 0; i < bmap->n_div; ++i)
2915                 if (!isl_int_is_zero(bmap->div[i][1+pos]))
2916                         return 0;
2917
2918         return 1;
2919 }
2920
2921 /*
2922  * Remove divs that don't occur in any of the constraints or other divs.
2923  * These can arise when dropping some of the variables in a quast
2924  * returned by piplib.
2925  */
2926 static struct isl_basic_map *remove_redundant_divs(struct isl_basic_map *bmap)
2927 {
2928         int i;
2929
2930         if (!bmap)
2931                 return NULL;
2932
2933         for (i = bmap->n_div-1; i >= 0; --i) {
2934                 if (!div_is_redundant(bmap, i))
2935                         continue;
2936                 bmap = isl_basic_map_drop_div(bmap, i);
2937         }
2938         return bmap;
2939 }
2940
2941 struct isl_basic_map *isl_basic_map_finalize(struct isl_basic_map *bmap)
2942 {
2943         bmap = remove_redundant_divs(bmap);
2944         if (!bmap)
2945                 return NULL;
2946         F_SET(bmap, ISL_BASIC_SET_FINAL);
2947         return bmap;
2948 }
2949
2950 struct isl_basic_set *isl_basic_set_finalize(struct isl_basic_set *bset)
2951 {
2952         return (struct isl_basic_set *)
2953                 isl_basic_map_finalize((struct isl_basic_map *)bset);
2954 }
2955
2956 struct isl_set *isl_set_finalize(struct isl_set *set)
2957 {
2958         int i;
2959
2960         if (!set)
2961                 return NULL;
2962         for (i = 0; i < set->n; ++i) {
2963                 set->p[i] = isl_basic_set_finalize(set->p[i]);
2964                 if (!set->p[i])
2965                         goto error;
2966         }
2967         return set;
2968 error:
2969         isl_set_free(set);
2970         return NULL;
2971 }
2972
2973 struct isl_map *isl_map_finalize(struct isl_map *map)
2974 {
2975         int i;
2976
2977         if (!map)
2978                 return NULL;
2979         for (i = 0; i < map->n; ++i) {
2980                 map->p[i] = isl_basic_map_finalize(map->p[i]);
2981                 if (!map->p[i])
2982                         goto error;
2983         }
2984         return map;
2985 error:
2986         isl_map_free(map);
2987         return NULL;
2988 }
2989
2990 struct isl_basic_map *isl_basic_map_identity(struct isl_ctx *ctx,
2991                 unsigned nparam, unsigned dim)
2992 {
2993         struct isl_basic_map *bmap;
2994         int i;
2995
2996         bmap = isl_basic_map_alloc(ctx, nparam, dim, dim, 0, dim, 0);
2997         if (!bmap)
2998                 goto error;
2999
3000         for (i = 0; i < dim; ++i) {
3001                 int j = isl_basic_map_alloc_equality(bmap);
3002                 if (j < 0)
3003                         goto error;
3004                 isl_seq_clr(bmap->eq[j],
3005                     1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->extra);
3006                 isl_int_set_si(bmap->eq[j][1+nparam+i], 1);
3007                 isl_int_set_si(bmap->eq[j][1+nparam+dim+i], -1);
3008         }
3009         return isl_basic_map_finalize(bmap);
3010 error:
3011         isl_basic_map_free(bmap);
3012         return NULL;
3013 }
3014
3015 struct isl_map *isl_map_identity(struct isl_ctx *ctx,
3016                 unsigned nparam, unsigned dim)
3017 {
3018         struct isl_map *map = isl_map_alloc(ctx, nparam, dim, dim, 1,
3019                                                 ISL_MAP_DISJOINT);
3020         if (!map)
3021                 goto error;
3022         map = isl_map_add(map,
3023                 isl_basic_map_identity(ctx, nparam, dim));
3024         return map;
3025 error:
3026         isl_map_free(map);
3027         return NULL;
3028 }
3029
3030 int isl_set_is_equal(struct isl_set *set1, struct isl_set *set2)
3031 {
3032         return isl_map_is_equal((struct isl_map *)set1, (struct isl_map *)set2);
3033 }
3034
3035 int isl_set_is_subset(struct isl_set *set1, struct isl_set *set2)
3036 {
3037         return isl_map_is_subset(
3038                         (struct isl_map *)set1, (struct isl_map *)set2);
3039 }
3040
3041 int isl_basic_map_is_subset(
3042                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3043 {
3044         int is_subset;
3045         struct isl_map *map1;
3046         struct isl_map *map2;
3047
3048         if (!bmap1 || !bmap2)
3049                 return -1;
3050
3051         map1 = isl_map_from_basic_map(isl_basic_map_copy(bmap1));
3052         map2 = isl_map_from_basic_map(isl_basic_map_copy(bmap2));
3053
3054         is_subset = isl_map_is_subset(map1, map2);
3055
3056         isl_map_free(map1);
3057         isl_map_free(map2);
3058
3059         return is_subset;
3060 }
3061
3062 int isl_basic_map_is_equal(
3063                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3064 {
3065         int is_subset;
3066
3067         if (!bmap1 || !bmap2)
3068                 return -1;
3069         is_subset = isl_basic_map_is_subset(bmap1, bmap2);
3070         if (is_subset != 1)
3071                 return is_subset;
3072         is_subset = isl_basic_map_is_subset(bmap2, bmap1);
3073         return is_subset;
3074 }
3075
3076 int isl_basic_set_is_equal(
3077                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
3078 {
3079         return isl_basic_map_is_equal(
3080                 (struct isl_basic_map *)bset1, (struct isl_basic_map *)bset2);
3081 }
3082
3083 int isl_map_is_empty(struct isl_map *map)
3084 {
3085         int i;
3086         int is_empty;
3087
3088         if (!map)
3089                 return -1;
3090         for (i = 0; i < map->n; ++i) {
3091                 is_empty = isl_basic_map_is_empty(map->p[i]);
3092                 if (is_empty < 0)
3093                         return -1;
3094                 if (!is_empty)
3095                         return 0;
3096         }
3097         return 1;
3098 }
3099
3100 int isl_set_is_empty(struct isl_set *set)
3101 {
3102         return isl_map_is_empty((struct isl_map *)set);
3103 }
3104
3105 int isl_map_is_subset(struct isl_map *map1, struct isl_map *map2)
3106 {
3107         int i;
3108         int is_subset = 0;
3109         struct isl_map *diff;
3110
3111         if (!map1 || !map2)
3112                 return -1;
3113
3114         if (isl_map_is_empty(map1))
3115                 return 1;
3116
3117         if (isl_map_is_empty(map2))
3118                 return 0;
3119
3120         diff = isl_map_subtract(isl_map_copy(map1), isl_map_copy(map2));
3121         if (!diff)
3122                 return -1;
3123
3124         is_subset = isl_map_is_empty(diff);
3125         isl_map_free(diff);
3126
3127         return is_subset;
3128 }
3129
3130 int isl_map_is_equal(struct isl_map *map1, struct isl_map *map2)
3131 {
3132         int is_subset;
3133
3134         if (!map1 || !map2)
3135                 return -1;
3136         is_subset = isl_map_is_subset(map1, map2);
3137         if (is_subset != 1)
3138                 return is_subset;
3139         is_subset = isl_map_is_subset(map2, map1);
3140         return is_subset;
3141 }
3142
3143 int isl_basic_map_is_strict_subset(
3144                 struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3145 {
3146         int is_subset;
3147
3148         if (!bmap1 || !bmap2)
3149                 return -1;
3150         is_subset = isl_basic_map_is_subset(bmap1, bmap2);
3151         if (is_subset != 1)
3152                 return is_subset;
3153         is_subset = isl_basic_map_is_subset(bmap2, bmap1);
3154         if (is_subset == -1)
3155                 return is_subset;
3156         return !is_subset;
3157 }
3158
3159 static int basic_map_contains(struct isl_basic_map *bmap, struct isl_vec *vec)
3160 {
3161         int i;
3162         unsigned total;
3163         isl_int s;
3164
3165         total = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3166         if (total != vec->size)
3167                 return -1;
3168
3169         isl_int_init(s);
3170
3171         for (i = 0; i < bmap->n_eq; ++i) {
3172                 isl_seq_inner_product(vec->block.data, bmap->eq[i], total, &s);
3173                 if (!isl_int_is_zero(s)) {
3174                         isl_int_clear(s);
3175                         return 0;
3176                 }
3177         }
3178
3179         for (i = 0; i < bmap->n_ineq; ++i) {
3180                 isl_seq_inner_product(vec->block.data, bmap->ineq[i], total, &s);
3181                 if (isl_int_is_neg(s)) {
3182                         isl_int_clear(s);
3183                         return 0;
3184                 }
3185         }
3186
3187         isl_int_clear(s);
3188
3189         return 1;
3190 }
3191
3192 int isl_basic_map_is_universe(struct isl_basic_map *bmap)
3193 {
3194         if (!bmap)
3195                 return -1;
3196         return bmap->n_eq == 0 && bmap->n_ineq == 0;
3197 }
3198
3199 int isl_basic_map_is_empty(struct isl_basic_map *bmap)
3200 {
3201         struct isl_basic_set *bset = NULL;
3202         struct isl_vec *sample = NULL;
3203         int empty;
3204         unsigned total;
3205
3206         if (!bmap)
3207                 return -1;
3208
3209         if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
3210                 return 1;
3211
3212         total = 1 + bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3213         if (bmap->sample && bmap->sample->size == total) {
3214                 int contains = basic_map_contains(bmap, bmap->sample);
3215                 if (contains < 0)
3216                         return -1;
3217                 if (contains)
3218                         return 0;
3219         }
3220         bset = isl_basic_map_underlying_set(isl_basic_map_copy(bmap));
3221         if (!bset)
3222                 return -1;
3223         sample = isl_basic_set_sample(bset);
3224         if (!sample)
3225                 return -1;
3226         empty = sample->size == 0;
3227         if (bmap->sample)
3228                 isl_vec_free(bmap->ctx, bmap->sample);
3229         bmap->sample = sample;
3230
3231         return empty;
3232 }
3233
3234 struct isl_map *isl_basic_map_union(
3235         struct isl_basic_map *bmap1, struct isl_basic_map *bmap2)
3236 {
3237         struct isl_map *map;
3238         if (!bmap1 || !bmap2)
3239                 return NULL;
3240
3241         isl_assert(bmap1->ctx, bmap1->nparam == bmap2->nparam, goto error);
3242         isl_assert(bmap1->ctx, bmap1->n_in == bmap2->n_in, goto error);
3243         isl_assert(bmap1->ctx, bmap1->n_out == bmap2->n_out, goto error);
3244
3245         map = isl_map_alloc(bmap1->ctx, bmap1->nparam,
3246                                 bmap1->n_in, bmap1->n_out, 2, 0);
3247         if (!map)
3248                 goto error;
3249         map = isl_map_add(map, bmap1);
3250         map = isl_map_add(map, bmap2);
3251         return map;
3252 error:
3253         isl_basic_map_free(bmap1);
3254         isl_basic_map_free(bmap2);
3255         return NULL;
3256 }
3257
3258 struct isl_set *isl_basic_set_union(
3259                 struct isl_basic_set *bset1, struct isl_basic_set *bset2)
3260 {
3261         return (struct isl_set *)isl_basic_map_union(
3262                                             (struct isl_basic_map *)bset1,
3263                                             (struct isl_basic_map *)bset2);
3264 }
3265
3266 /* Order divs such that any div only depends on previous divs */
3267 static struct isl_basic_map *order_divs(struct isl_basic_map *bmap)
3268 {
3269         int i;
3270         unsigned off = bmap->nparam + bmap->n_in + bmap->n_out;
3271
3272         for (i = 0; i < bmap->n_div; ++i) {
3273                 int pos;
3274                 pos = isl_seq_first_non_zero(bmap->div[i]+1+1+off+i,
3275                                                             bmap->n_div-i);
3276                 if (pos == -1)
3277                         continue;
3278                 swap_div(bmap, i, pos);
3279                 --i;
3280         }
3281         return bmap;
3282 }
3283
3284 static int find_div(struct isl_basic_map *dst,
3285                         struct isl_basic_map *src, unsigned div)
3286 {
3287         int i;
3288
3289         unsigned total = src->nparam + src->n_in + src->n_out + src->n_div;
3290
3291         for (i = 0; i < dst->n_div; ++i)
3292                 if (isl_seq_eq(dst->div[i], src->div[div], 1+1+total) &&
3293                     isl_seq_first_non_zero(dst->div[i]+1+1+total,
3294                                                 dst->n_div - src->n_div) == -1)
3295                         return i;
3296         return -1;
3297 }
3298
3299 struct isl_basic_map *isl_basic_map_align_divs(
3300                 struct isl_basic_map *dst, struct isl_basic_map *src)
3301 {
3302         int i;
3303         unsigned total = src->nparam + src->n_in + src->n_out + src->n_div;
3304
3305         if (src->n_div == 0)
3306                 return dst;
3307
3308         src = order_divs(src);
3309         dst = isl_basic_map_extend(dst, dst->nparam, dst->n_in,
3310                         dst->n_out, src->n_div, 0, 2 * src->n_div);
3311         if (!dst)
3312                 return NULL;
3313         for (i = 0; i < src->n_div; ++i) {
3314                 int j = find_div(dst, src, i);
3315                 if (j < 0) {
3316                         j = isl_basic_map_alloc_div(dst);
3317                         if (j < 0)
3318                                 goto error;
3319                         isl_seq_cpy(dst->div[j], src->div[i], 1+1+total);
3320                         isl_seq_clr(dst->div[j]+1+1+total,
3321                                                     dst->extra - src->n_div);
3322                         if (add_div_constraints(dst, j) < 0)
3323                                 goto error;
3324                 }
3325                 if (j != i)
3326                         swap_div(dst, i, j);
3327         }
3328         return dst;
3329 error:
3330         isl_basic_map_free(dst);
3331         return NULL;
3332 }
3333
3334 struct isl_map *isl_map_align_divs(struct isl_map *map)
3335 {
3336         int i;
3337
3338         map = isl_map_compute_divs(map);
3339         map = isl_map_cow(map);
3340         if (!map)
3341                 return NULL;
3342
3343         for (i = 1; i < map->n; ++i)
3344                 map->p[0] = isl_basic_map_align_divs(map->p[0], map->p[i]);
3345         for (i = 1; i < map->n; ++i)
3346                 map->p[i] = isl_basic_map_align_divs(map->p[i], map->p[0]);
3347
3348         return map;
3349 }
3350
3351 static struct isl_map *add_cut_constraint(struct isl_map *dst,
3352                 struct isl_basic_map *src, isl_int *c,
3353                 unsigned len, int oppose)
3354 {
3355         struct isl_basic_map *copy = NULL;
3356         int is_empty;
3357         int k;
3358         unsigned total;
3359
3360         copy = isl_basic_map_copy(src);
3361         copy = isl_basic_map_cow(copy);
3362         if (!copy)
3363                 goto error;
3364         copy = isl_basic_map_extend(copy,
3365                 copy->nparam, copy->n_in, copy->n_out, 0, 0, 1);
3366         k = isl_basic_map_alloc_inequality(copy);
3367         if (k < 0)
3368                 goto error;
3369         if (oppose)
3370                 isl_seq_neg(copy->ineq[k], c, len);
3371         else
3372                 isl_seq_cpy(copy->ineq[k], c, len);
3373         total = 1 + copy->nparam + copy->n_in + copy->n_out + copy->extra;
3374         isl_seq_clr(copy->ineq[k]+len, total - len);
3375         isl_inequality_negate(copy, k);
3376         copy = isl_basic_map_simplify(copy);
3377         copy = isl_basic_map_finalize(copy);
3378         is_empty = isl_basic_map_is_empty(copy);
3379         if (is_empty < 0)
3380                 goto error;
3381         if (!is_empty)
3382                 dst = isl_map_add(dst, copy);
3383         else
3384                 isl_basic_map_free(copy);
3385         return dst;
3386 error:
3387         isl_basic_map_free(copy);
3388         isl_map_free(dst);
3389         return NULL;
3390 }
3391
3392 static struct isl_map *subtract(struct isl_map *map, struct isl_basic_map *bmap)
3393 {
3394         int i, j, k;
3395         unsigned flags = 0;
3396         struct isl_map *rest = NULL;
3397         unsigned max;
3398         unsigned total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
3399
3400         assert(bmap);
3401
3402         if (!map)
3403                 goto error;
3404
3405         if (F_ISSET(map, ISL_MAP_DISJOINT))
3406                 FL_SET(flags, ISL_MAP_DISJOINT);
3407
3408         max = map->n * (2 * bmap->n_eq + bmap->n_ineq);
3409         rest = isl_map_alloc(map->ctx, map->nparam, map->n_in, map->n_out,
3410                                 max, flags);
3411         if (!rest)
3412                 goto error;
3413
3414         for (i = 0; i < map->n; ++i) {
3415                 map->p[i] = isl_basic_map_align_divs(map->p[i], bmap);
3416                 if (!map->p[i])
3417                         goto error;
3418         }
3419
3420         for (j = 0; j < map->n; ++j)
3421                 map->p[j] = isl_basic_map_cow(map->p[j]);
3422
3423         for (i = 0; i < bmap->n_eq; ++i) {
3424                 for (j = 0; j < map->n; ++j) {
3425                         rest = add_cut_constraint(rest,
3426                                 map->p[j], bmap->eq[i], 1+total, 0);
3427                         if (!rest)
3428                                 goto error;
3429
3430                         rest = add_cut_constraint(rest,
3431                                 map->p[j], bmap->eq[i], 1+total, 1);
3432                         if (!rest)
3433                                 goto error;
3434
3435                         map->p[j] = isl_basic_map_extend(map->p[j],
3436                                 map->p[j]->nparam, map->p[j]->n_in,
3437                                 map->p[j]->n_out, 0, 1, 0);
3438                         if (!map->p[j])
3439                                 goto error;
3440                         k = isl_basic_map_alloc_equality(map->p[j]);
3441                         if (k < 0)
3442                                 goto error;
3443                         isl_seq_cpy(map->p[j]->eq[k], bmap->eq[i], 1+total);
3444                         isl_seq_clr(map->p[j]->eq[k]+1+total,
3445                                         map->p[j]->extra - bmap->n_div);
3446                 }
3447         }
3448
3449         for (i = 0; i < bmap->n_ineq; ++i) {
3450                 for (j = 0; j < map->n; ++j) {
3451                         rest = add_cut_constraint(rest,
3452                                 map->p[j], bmap->ineq[i], 1+total, 0);
3453                         if (!rest)
3454                                 goto error;
3455
3456                         map->p[j] = isl_basic_map_extend(map->p[j],
3457                                 map->p[j]->nparam, map->p[j]->n_in,
3458                                 map->p[j]->n_out, 0, 0, 1);
3459                         if (!map->p[j])
3460                                 goto error;
3461                         k = isl_basic_map_alloc_inequality(map->p[j]);
3462                         if (k < 0)
3463                                 goto error;
3464                         isl_seq_cpy(map->p[j]->ineq[k], bmap->ineq[i], 1+total);
3465                         isl_seq_clr(map->p[j]->ineq[k]+1+total,
3466                                         map->p[j]->extra - bmap->n_div);
3467                 }
3468         }
3469
3470         isl_map_free(map);
3471         return rest;
3472 error:
3473         isl_map_free(map);
3474         isl_map_free(rest);
3475         return NULL;
3476 }
3477
3478 struct isl_map *isl_map_subtract(struct isl_map *map1, struct isl_map *map2)
3479 {
3480         int i;
3481         if (!map1 || !map2)
3482                 goto error;
3483
3484         isl_assert(map1->ctx, map1->nparam == map2->nparam, goto error);
3485         isl_assert(map1->ctx, map1->n_in == map2->n_in, goto error);
3486         isl_assert(map1->ctx, map1->n_out == map2->n_out, goto error);
3487
3488         if (isl_map_is_empty(map2)) {
3489                 isl_map_free(map2);
3490                 return map1;
3491         }
3492
3493         map1 = isl_map_compute_divs(map1);
3494         map2 = isl_map_compute_divs(map2);
3495         if (!map1 || !map2)
3496                 goto error;
3497
3498         for (i = 0; map1 && i < map2->n; ++i)
3499                 map1 = subtract(map1, map2->p[i]);
3500
3501         isl_map_free(map2);
3502         return map1;
3503 error:
3504         isl_map_free(map1);
3505         isl_map_free(map2);
3506         return NULL;
3507 }
3508
3509 struct isl_set *isl_set_subtract(struct isl_set *set1, struct isl_set *set2)
3510 {
3511         return (struct isl_set *)
3512                 isl_map_subtract(
3513                         (struct isl_map *)set1, (struct isl_map *)set2);
3514 }
3515
3516 struct isl_set *isl_set_apply(struct isl_set *set, struct isl_map *map)
3517 {
3518         if (!set || !map)
3519                 goto error;
3520         isl_assert(set->ctx, set->dim == map->n_in, goto error);
3521         map = isl_map_intersect_domain(map, set);
3522         set = isl_map_range(map);
3523         return set;
3524 error:
3525         isl_set_free(set);
3526         isl_map_free(map);
3527         return NULL;
3528 }
3529
3530 /* There is no need to cow as removing empty parts doesn't change
3531  * the meaning of the set.
3532  */
3533 struct isl_map *isl_map_remove_empty_parts(struct isl_map *map)
3534 {
3535         int i;
3536
3537         if (!map)
3538                 return NULL;
3539
3540         for (i = map->n-1; i >= 0; --i) {
3541                 if (!F_ISSET(map->p[i], ISL_BASIC_MAP_EMPTY))
3542                         continue;
3543                 isl_basic_map_free(map->p[i]);
3544                 if (i != map->n-1)
3545                         map->p[i] = map->p[map->n-1];
3546                 map->n--;
3547         }
3548
3549         return map;
3550 }
3551
3552 struct isl_set *isl_set_remove_empty_parts(struct isl_set *set)
3553 {
3554         return (struct isl_set *)
3555                 isl_map_remove_empty_parts((struct isl_map *)set);
3556 }
3557
3558 struct isl_basic_set *isl_set_copy_basic_set(struct isl_set *set)
3559 {
3560         struct isl_basic_set *bset;
3561         if (!set || set->n == 0)
3562                 return NULL;
3563         bset = set->p[set->n-1];
3564         isl_assert(set->ctx, F_ISSET(bset, ISL_BASIC_SET_FINAL), return NULL);
3565         return isl_basic_set_copy(bset);
3566 }
3567
3568 struct isl_set *isl_set_drop_basic_set(struct isl_set *set,
3569                                                 struct isl_basic_set *bset)
3570 {
3571         int i;
3572
3573         if (!set || !bset)
3574                 goto error;
3575         for (i = set->n-1; i >= 0; --i) {
3576                 if (set->p[i] != bset)
3577                         continue;
3578                 set = isl_set_cow(set);
3579                 if (!set)
3580                         goto error;
3581                 isl_basic_set_free(set->p[i]);
3582                 if (i != set->n-1)
3583                         set->p[i] = set->p[set->n-1];
3584                 set->n--;
3585                 return set;
3586         }
3587         isl_basic_set_free(bset);
3588         return set;
3589 error:
3590         isl_set_free(set);
3591         isl_basic_set_free(bset);
3592         return NULL;
3593 }