isl_local_space.c

   1 /*
   2  * Copyright 2011      INRIA Saclay
   3  * Copyright 2012-2014 Ecole Normale Superieure
   4  *
   5  * Use of this software is governed by the MIT license
   6  *
   7  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
   8  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
   9  * 91893 Orsay, France
  10  * and Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
  11  */
  12
  13 #include <isl_ctx_private.h>
  14 #include <isl_map_private.h>
  15 #include <isl_local_space_private.h>
  16 #include <isl_space_private.h>
  17 #include <isl_mat_private.h>
  18 #include <isl_aff_private.h>
  19 #include <isl_vec_private.h>
  20 #include <isl_seq.h>
  21
  22 isl_ctx *isl_local_space_get_ctx(__isl_keep isl_local_space *ls)
  23 {
  24         return ls ? ls->dim->ctx : NULL;
  25 }
  26
  27 __isl_give isl_local_space *isl_local_space_alloc_div(__isl_take isl_space *dim,
  28         __isl_take isl_mat *div)
  29 {
  30         isl_ctx *ctx;
  31         isl_local_space *ls = NULL;
  32
  33         if (!dim || !div)
  34                 goto error;
  35
  36         ctx = isl_space_get_ctx(dim);
  37         ls = isl_calloc_type(ctx, struct isl_local_space);
  38         if (!ls)
  39                 goto error;
  40
  41         ls->ref = 1;
  42         ls->dim = dim;
  43         ls->div = div;
  44
  45         return ls;
  46 error:
  47         isl_mat_free(div);
  48         isl_space_free(dim);
  49         isl_local_space_free(ls);
  50         return NULL;
  51 }
  52
  53 __isl_give isl_local_space *isl_local_space_alloc(__isl_take isl_space *dim,
  54         unsigned n_div)
  55 {
  56         isl_ctx *ctx;
  57         isl_mat *div;
  58         unsigned total;
  59
  60         if (!dim)
  61                 return NULL;
  62
  63         total = isl_space_dim(dim, isl_dim_all);
  64
  65         ctx = isl_space_get_ctx(dim);
  66         div = isl_mat_alloc(ctx, n_div, 1 + 1 + total + n_div);
  67         return isl_local_space_alloc_div(dim, div);
  68 }
  69
  70 __isl_give isl_local_space *isl_local_space_from_space(__isl_take isl_space *dim)
  71 {
  72         return isl_local_space_alloc(dim, 0);
  73 }
  74
  75 __isl_give isl_local_space *isl_local_space_copy(__isl_keep isl_local_space *ls)
  76 {
  77         if (!ls)
  78                 return NULL;
  79
  80         ls->ref++;
  81         return ls;
  82 }
  83
  84 __isl_give isl_local_space *isl_local_space_dup(__isl_keep isl_local_space *ls)
  85 {
  86         if (!ls)
  87                 return NULL;
  88
  89         return isl_local_space_alloc_div(isl_space_copy(ls->dim),
  90                                          isl_mat_copy(ls->div));
  91
  92 }
  93
  94 __isl_give isl_local_space *isl_local_space_cow(__isl_take isl_local_space *ls)
  95 {
  96         if (!ls)
  97                 return NULL;
  98
  99         if (ls->ref == 1)
 100                 return ls;
 101         ls->ref--;
 102         return isl_local_space_dup(ls);
 103 }
 104
 105 __isl_null isl_local_space *isl_local_space_free(
 106         __isl_take isl_local_space *ls)
 107 {
 108         if (!ls)
 109                 return NULL;
 110
 111         if (--ls->ref > 0)
 112                 return NULL;
 113
 114         isl_space_free(ls->dim);
 115         isl_mat_free(ls->div);
 116
 117         free(ls);
 118
 119         return NULL;
 120 }
 121
 122 /* Is the local space that of a parameter domain?
 123  */
 124 isl_bool isl_local_space_is_params(__isl_keep isl_local_space *ls)
 125 {
 126         if (!ls)
 127                 return isl_bool_error;
 128         return isl_space_is_params(ls->dim);
 129 }
 130
 131 /* Is the local space that of a set?
 132  */
 133 isl_bool isl_local_space_is_set(__isl_keep isl_local_space *ls)
 134 {
 135         return ls ? isl_space_is_set(ls->dim) : isl_bool_error;
 136 }
 137
 138 /* Return true if the two local spaces are identical, with identical
 139  * expressions for the integer divisions.
 140  */
 141 isl_bool isl_local_space_is_equal(__isl_keep isl_local_space *ls1,
 142         __isl_keep isl_local_space *ls2)
 143 {
 144         isl_bool equal;
 145
 146         if (!ls1 || !ls2)
 147                 return isl_bool_error;
 148
 149         equal = isl_space_is_equal(ls1->dim, ls2->dim);
 150         if (equal < 0 || !equal)
 151                 return equal;
 152
 153         if (!isl_local_space_divs_known(ls1))
 154                 return isl_bool_false;
 155         if (!isl_local_space_divs_known(ls2))
 156                 return isl_bool_false;
 157
 158         return isl_mat_is_equal(ls1->div, ls2->div);
 159 }
 160
 161 /* Compare two isl_local_spaces.
 162  *
 163  * Return -1 if "ls1" is "smaller" than "ls2", 1 if "ls1" is "greater"
 164  * than "ls2" and 0 if they are equal.
 165  *
 166  * The order is fairly arbitrary.  We do "prefer" divs that only involve
 167  * earlier dimensions in the sense that we consider local spaces where
 168  * the first differing div involves earlier dimensions to be smaller.
 169  */
 170 int isl_local_space_cmp(__isl_keep isl_local_space *ls1,
 171         __isl_keep isl_local_space *ls2)
 172 {
 173         int i;
 174         int cmp;
 175         int known1, known2;
 176         int last1, last2;
 177         int n_col;
 178
 179         if (ls1 == ls2)
 180                 return 0;
 181         if (!ls1)
 182                 return -1;
 183         if (!ls2)
 184                 return 1;
 185
 186         cmp = isl_space_cmp(ls1->dim, ls2->dim);
 187         if (cmp != 0)
 188                 return cmp;
 189
 190         if (ls1->div->n_row != ls2->div->n_row)
 191                 return ls1->div->n_row - ls2->div->n_row;
 192
 193         n_col = isl_mat_cols(ls1->div);
 194         for (i = 0; i < ls1->div->n_row; ++i) {
 195                 known1 = isl_local_space_div_is_known(ls1, i);
 196                 known2 = isl_local_space_div_is_known(ls2, i);
 197                 if (!known1 && !known2)
 198                         continue;
 199                 if (!known1)
 200                         return 1;
 201                 if (!known2)
 202                         return -1;
 203                 last1 = isl_seq_last_non_zero(ls1->div->row[i] + 1, n_col - 1);
 204                 last2 = isl_seq_last_non_zero(ls2->div->row[i] + 1, n_col - 1);
 205                 if (last1 != last2)
 206                         return last1 - last2;
 207                 cmp = isl_seq_cmp(ls1->div->row[i], ls2->div->row[i], n_col);
 208                 if (cmp != 0)
 209                         return cmp;
 210         }
 211
 212         return 0;
 213 }
 214
 215 int isl_local_space_dim(__isl_keep isl_local_space *ls,
 216         enum isl_dim_type type)
 217 {
 218         if (!ls)
 219                 return 0;
 220         if (type == isl_dim_div)
 221                 return ls->div->n_row;
 222         if (type == isl_dim_all)
 223                 return isl_space_dim(ls->dim, isl_dim_all) + ls->div->n_row;
 224         return isl_space_dim(ls->dim, type);
 225 }
 226
 227 unsigned isl_local_space_offset(__isl_keep isl_local_space *ls,
 228         enum isl_dim_type type)
 229 {
 230         isl_space *dim;
 231
 232         if (!ls)
 233                 return 0;
 234
 235         dim = ls->dim;
 236         switch (type) {
 237         case isl_dim_cst:       return 0;
 238         case isl_dim_param:     return 1;
 239         case isl_dim_in:        return 1 + dim->nparam;
 240         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
 241         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
 242         default:                return 0;
 243         }
 244 }
 245
 246 /* Return the position of the dimension of the given type and name
 247  * in "ls".
 248  * Return -1 if no such dimension can be found.
 249  */
 250 int isl_local_space_find_dim_by_name(__isl_keep isl_local_space *ls,
 251         enum isl_dim_type type, const char *name)
 252 {
 253         if (!ls)
 254                 return -1;
 255         if (type == isl_dim_div)
 256                 return -1;
 257         return isl_space_find_dim_by_name(ls->dim, type, name);
 258 }
 259
 260 /* Does the given dimension have a name?
 261  */
 262 isl_bool isl_local_space_has_dim_name(__isl_keep isl_local_space *ls,
 263         enum isl_dim_type type, unsigned pos)
 264 {
 265         return ls ? isl_space_has_dim_name(ls->dim, type, pos) : isl_bool_error;
 266 }
 267
 268 const char *isl_local_space_get_dim_name(__isl_keep isl_local_space *ls,
 269         enum isl_dim_type type, unsigned pos)
 270 {
 271         return ls ? isl_space_get_dim_name(ls->dim, type, pos) : NULL;
 272 }
 273
 274 isl_bool isl_local_space_has_dim_id(__isl_keep isl_local_space *ls,
 275         enum isl_dim_type type, unsigned pos)
 276 {
 277         return ls ? isl_space_has_dim_id(ls->dim, type, pos) : isl_bool_error;
 278 }
 279
 280 __isl_give isl_id *isl_local_space_get_dim_id(__isl_keep isl_local_space *ls,
 281         enum isl_dim_type type, unsigned pos)
 282 {
 283         return ls ? isl_space_get_dim_id(ls->dim, type, pos) : NULL;
 284 }
 285
 286 __isl_give isl_aff *isl_local_space_get_div(__isl_keep isl_local_space *ls,
 287         int pos)
 288 {
 289         isl_aff *aff;
 290
 291         if (!ls)
 292                 return NULL;
 293
 294         if (pos < 0 || pos >= ls->div->n_row)
 295                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 296                         "index out of bounds", return NULL);
 297
 298         if (isl_int_is_zero(ls->div->row[pos][0]))
 299                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 300                         "expression of div unknown", return NULL);
 301         if (!isl_local_space_is_set(ls))
 302                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 303                         "cannot represent divs of map spaces", return NULL);
 304
 305         aff = isl_aff_alloc(isl_local_space_copy(ls));
 306         if (!aff)
 307                 return NULL;
 308         isl_seq_cpy(aff->v->el, ls->div->row[pos], aff->v->size);
 309         return aff;
 310 }
 311
 312 __isl_give isl_space *isl_local_space_get_space(__isl_keep isl_local_space *ls)
 313 {
 314         if (!ls)
 315                 return NULL;
 316
 317         return isl_space_copy(ls->dim);
 318 }
 319
 320 /* Replace the identifier of the tuple of type "type" by "id".
 321  */
 322 __isl_give isl_local_space *isl_local_space_set_tuple_id(
 323         __isl_take isl_local_space *ls,
 324         enum isl_dim_type type, __isl_take isl_id *id)
 325 {
 326         ls = isl_local_space_cow(ls);
 327         if (!ls)
 328                 goto error;
 329         ls->dim = isl_space_set_tuple_id(ls->dim, type, id);
 330         if (!ls->dim)
 331                 return isl_local_space_free(ls);
 332         return ls;
 333 error:
 334         isl_id_free(id);
 335         return NULL;
 336 }
 337
 338 __isl_give isl_local_space *isl_local_space_set_dim_name(
 339         __isl_take isl_local_space *ls,
 340         enum isl_dim_type type, unsigned pos, const char *s)
 341 {
 342         ls = isl_local_space_cow(ls);
 343         if (!ls)
 344                 return NULL;
 345         ls->dim = isl_space_set_dim_name(ls->dim, type, pos, s);
 346         if (!ls->dim)
 347                 return isl_local_space_free(ls);
 348
 349         return ls;
 350 }
 351
 352 __isl_give isl_local_space *isl_local_space_set_dim_id(
 353         __isl_take isl_local_space *ls,
 354         enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
 355 {
 356         ls = isl_local_space_cow(ls);
 357         if (!ls)
 358                 goto error;
 359         ls->dim = isl_space_set_dim_id(ls->dim, type, pos, id);
 360         if (!ls->dim)
 361                 return isl_local_space_free(ls);
 362
 363         return ls;
 364 error:
 365         isl_id_free(id);
 366         return NULL;
 367 }
 368
 369 __isl_give isl_local_space *isl_local_space_reset_space(
 370         __isl_take isl_local_space *ls, __isl_take isl_space *dim)
 371 {
 372         ls = isl_local_space_cow(ls);
 373         if (!ls || !dim)
 374                 goto error;
 375
 376         isl_space_free(ls->dim);
 377         ls->dim = dim;
 378
 379         return ls;
 380 error:
 381         isl_local_space_free(ls);
 382         isl_space_free(dim);
 383         return NULL;
 384 }
 385
 386 /* Reorder the columns of the given div definitions according to the
 387  * given reordering.
 388  * The order of the divs themselves is assumed not to change.
 389  */
 390 static __isl_give isl_mat *reorder_divs(__isl_take isl_mat *div,
 391         __isl_take isl_reordering *r)
 392 {
 393         int i, j;
 394         isl_mat *mat;
 395         int extra;
 396
 397         if (!div || !r)
 398                 goto error;
 399
 400         extra = isl_space_dim(r->dim, isl_dim_all) + div->n_row - r->len;
 401         mat = isl_mat_alloc(div->ctx, div->n_row, div->n_col + extra);
 402         if (!mat)
 403                 goto error;
 404
 405         for (i = 0; i < div->n_row; ++i) {
 406                 isl_seq_cpy(mat->row[i], div->row[i], 2);
 407                 isl_seq_clr(mat->row[i] + 2, mat->n_col - 2);
 408                 for (j = 0; j < r->len; ++j)
 409                         isl_int_set(mat->row[i][2 + r->pos[j]],
 410                                     div->row[i][2 + j]);
 411         }
 412
 413         isl_reordering_free(r);
 414         isl_mat_free(div);
 415         return mat;
 416 error:
 417         isl_reordering_free(r);
 418         isl_mat_free(div);
 419         return NULL;
 420 }
 421
 422 /* Reorder the dimensions of "ls" according to the given reordering.
 423  * The reordering r is assumed to have been extended with the local
 424  * variables, leaving them in the same order.
 425  */
 426 __isl_give isl_local_space *isl_local_space_realign(
 427         __isl_take isl_local_space *ls, __isl_take isl_reordering *r)
 428 {
 429         ls = isl_local_space_cow(ls);
 430         if (!ls || !r)
 431                 goto error;
 432
 433         ls->div = reorder_divs(ls->div, isl_reordering_copy(r));
 434         if (!ls->div)
 435                 goto error;
 436
 437         ls = isl_local_space_reset_space(ls, isl_space_copy(r->dim));
 438
 439         isl_reordering_free(r);
 440         return ls;
 441 error:
 442         isl_local_space_free(ls);
 443         isl_reordering_free(r);
 444         return NULL;
 445 }
 446
 447 __isl_give isl_local_space *isl_local_space_add_div(
 448         __isl_take isl_local_space *ls, __isl_take isl_vec *div)
 449 {
 450         ls = isl_local_space_cow(ls);
 451         if (!ls || !div)
 452                 goto error;
 453
 454         if (ls->div->n_col != div->size)
 455                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 456                         "incompatible dimensions", goto error);
 457
 458         ls->div = isl_mat_add_zero_cols(ls->div, 1);
 459         ls->div = isl_mat_add_rows(ls->div, 1);
 460         if (!ls->div)
 461                 goto error;
 462
 463         isl_seq_cpy(ls->div->row[ls->div->n_row - 1], div->el, div->size);
 464         isl_int_set_si(ls->div->row[ls->div->n_row - 1][div->size], 0);
 465
 466         isl_vec_free(div);
 467         return ls;
 468 error:
 469         isl_local_space_free(ls);
 470         isl_vec_free(div);
 471         return NULL;
 472 }
 473
 474 __isl_give isl_local_space *isl_local_space_replace_divs(
 475         __isl_take isl_local_space *ls, __isl_take isl_mat *div)
 476 {
 477         ls = isl_local_space_cow(ls);
 478
 479         if (!ls || !div)
 480                 goto error;
 481
 482         isl_mat_free(ls->div);
 483         ls->div = div;
 484         return ls;
 485 error:
 486         isl_mat_free(div);
 487         isl_local_space_free(ls);
 488         return NULL;
 489 }
 490
 491 /* Copy row "s" of "src" to row "d" of "dst", applying the expansion
 492  * defined by "exp".
 493  */
 494 static void expand_row(__isl_keep isl_mat *dst, int d,
 495         __isl_keep isl_mat *src, int s, int *exp)
 496 {
 497         int i;
 498         unsigned c = src->n_col - src->n_row;
 499
 500         isl_seq_cpy(dst->row[d], src->row[s], c);
 501         isl_seq_clr(dst->row[d] + c, dst->n_col - c);
 502
 503         for (i = 0; i < s; ++i)
 504                 isl_int_set(dst->row[d][c + exp[i]], src->row[s][c + i]);
 505 }
 506
 507 /* Compare (known) divs.
 508  * Return non-zero if at least one of the two divs is unknown.
 509  * In particular, if both divs are unknown, we respect their
 510  * current order.  Otherwise, we sort the known div after the unknown
 511  * div only if the known div depends on the unknown div.
 512  */
 513 static int cmp_row(isl_int *row_i, isl_int *row_j, int i, int j,
 514         unsigned n_row, unsigned n_col)
 515 {
 516         int li, lj;
 517         int unknown_i, unknown_j;
 518
 519         unknown_i = isl_int_is_zero(row_i[0]);
 520         unknown_j = isl_int_is_zero(row_j[0]);
 521
 522         if (unknown_i && unknown_j)
 523                 return i - j;
 524
 525         if (unknown_i)
 526                 li = n_col - n_row + i;
 527         else
 528                 li = isl_seq_last_non_zero(row_i, n_col);
 529         if (unknown_j)
 530                 lj = n_col - n_row + j;
 531         else
 532                 lj = isl_seq_last_non_zero(row_j, n_col);
 533
 534         if (li != lj)
 535                 return li - lj;
 536
 537         return isl_seq_cmp(row_i, row_j, n_col);
 538 }
 539
 540 /* Call cmp_row for divs in a matrix.
 541  */
 542 int isl_mat_cmp_div(__isl_keep isl_mat *div, int i, int j)
 543 {
 544         return cmp_row(div->row[i], div->row[j], i, j, div->n_row, div->n_col);
 545 }
 546
 547 /* Call cmp_row for divs in a basic map.
 548  */
 549 static int bmap_cmp_row(__isl_keep isl_basic_map *bmap, int i, int j,
 550         unsigned total)
 551 {
 552         return cmp_row(bmap->div[i], bmap->div[j], i, j, bmap->n_div, total);
 553 }
 554
 555 /* Sort the divs in "bmap".
 556  *
 557  * We first make sure divs are placed after divs on which they depend.
 558  * Then we perform a simple insertion sort based on the same ordering
 559  * that is used in isl_merge_divs.
 560  */
 561 __isl_give isl_basic_map *isl_basic_map_sort_divs(
 562         __isl_take isl_basic_map *bmap)
 563 {
 564         int i, j;
 565         unsigned total;
 566
 567         bmap = isl_basic_map_order_divs(bmap);
 568         if (!bmap)
 569                 return NULL;
 570         if (bmap->n_div <= 1)
 571                 return bmap;
 572
 573         total = 2 + isl_basic_map_total_dim(bmap);
 574         for (i = 1; i < bmap->n_div; ++i) {
 575                 for (j = i - 1; j >= 0; --j) {
 576                         if (bmap_cmp_row(bmap, j, j + 1, total) <= 0)
 577                                 break;
 578                         isl_basic_map_swap_div(bmap, j, j + 1);
 579                 }
 580         }
 581
 582         return bmap;
 583 }
 584
 585 /* Sort the divs in the basic maps of "map".
 586  */
 587 __isl_give isl_map *isl_map_sort_divs(__isl_take isl_map *map)
 588 {
 589         return isl_map_inline_foreach_basic_map(map, &isl_basic_map_sort_divs);
 590 }
 591
 592 /* Combine the two lists of divs into a single list.
 593  * For each row i in div1, exp1[i] is set to the position of the corresponding
 594  * row in the result.  Similarly for div2 and exp2.
 595  * This function guarantees
 596  *      exp1[i] >= i
 597  *      exp1[i+1] > exp1[i]
 598  * For optimal merging, the two input list should have been sorted.
 599  */
 600 __isl_give isl_mat *isl_merge_divs(__isl_keep isl_mat *div1,
 601         __isl_keep isl_mat *div2, int *exp1, int *exp2)
 602 {
 603         int i, j, k;
 604         isl_mat *div = NULL;
 605         unsigned d;
 606
 607         if (!div1 || !div2)
 608                 return NULL;
 609
 610         d = div1->n_col - div1->n_row;
 611         div = isl_mat_alloc(div1->ctx, 1 + div1->n_row + div2->n_row,
 612                                 d + div1->n_row + div2->n_row);
 613         if (!div)
 614                 return NULL;
 615
 616         for (i = 0, j = 0, k = 0; i < div1->n_row && j < div2->n_row; ++k) {
 617                 int cmp;
 618
 619                 expand_row(div, k, div1, i, exp1);
 620                 expand_row(div, k + 1, div2, j, exp2);
 621
 622                 cmp = isl_mat_cmp_div(div, k, k + 1);
 623                 if (cmp == 0) {
 624                         exp1[i++] = k;
 625                         exp2[j++] = k;
 626                 } else if (cmp < 0) {
 627                         exp1[i++] = k;
 628                 } else {
 629                         exp2[j++] = k;
 630                         isl_seq_cpy(div->row[k], div->row[k + 1], div->n_col);
 631                 }
 632         }
 633         for (; i < div1->n_row; ++i, ++k) {
 634                 expand_row(div, k, div1, i, exp1);
 635                 exp1[i] = k;
 636         }
 637         for (; j < div2->n_row; ++j, ++k) {
 638                 expand_row(div, k, div2, j, exp2);
 639                 exp2[j] = k;
 640         }
 641
 642         div->n_row = k;
 643         div->n_col = d + k;
 644
 645         return div;
 646 }
 647
 648 /* Swap divs "a" and "b" in "ls".
 649  */
 650 __isl_give isl_local_space *isl_local_space_swap_div(
 651         __isl_take isl_local_space *ls, int a, int b)
 652 {
 653         int offset;
 654
 655         ls = isl_local_space_cow(ls);
 656         if (!ls)
 657                 return NULL;
 658         if (a < 0 || a >= ls->div->n_row || b < 0 || b >= ls->div->n_row)
 659                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 660                         "index out of bounds", return isl_local_space_free(ls));
 661         offset = ls->div->n_col - ls->div->n_row;
 662         ls->div = isl_mat_swap_cols(ls->div, offset + a, offset + b);
 663         ls->div = isl_mat_swap_rows(ls->div, a, b);
 664         if (!ls->div)
 665                 return isl_local_space_free(ls);
 666         return ls;
 667 }
 668
 669 /* Construct a local space that contains all the divs in either
 670  * "ls1" or "ls2".
 671  */
 672 __isl_give isl_local_space *isl_local_space_intersect(
 673         __isl_take isl_local_space *ls1, __isl_take isl_local_space *ls2)
 674 {
 675         isl_ctx *ctx;
 676         int *exp1 = NULL;
 677         int *exp2 = NULL;
 678         isl_mat *div;
 679         int equal;
 680
 681         if (!ls1 || !ls2)
 682                 goto error;
 683
 684         ctx = isl_local_space_get_ctx(ls1);
 685         if (!isl_space_is_equal(ls1->dim, ls2->dim))
 686                 isl_die(ctx, isl_error_invalid,
 687                         "spaces should be identical", goto error);
 688
 689         if (ls2->div->n_row == 0) {
 690                 isl_local_space_free(ls2);
 691                 return ls1;
 692         }
 693
 694         if (ls1->div->n_row == 0) {
 695                 isl_local_space_free(ls1);
 696                 return ls2;
 697         }
 698
 699         exp1 = isl_alloc_array(ctx, int, ls1->div->n_row);
 700         exp2 = isl_alloc_array(ctx, int, ls2->div->n_row);
 701         if (!exp1 || !exp2)
 702                 goto error;
 703
 704         div = isl_merge_divs(ls1->div, ls2->div, exp1, exp2);
 705         if (!div)
 706                 goto error;
 707
 708         equal = isl_mat_is_equal(ls1->div, div);
 709         if (equal < 0)
 710                 goto error;
 711         if (!equal)
 712                 ls1 = isl_local_space_cow(ls1);
 713         if (!ls1)
 714                 goto error;
 715
 716         free(exp1);
 717         free(exp2);
 718         isl_local_space_free(ls2);
 719         isl_mat_free(ls1->div);
 720         ls1->div = div;
 721
 722         return ls1;
 723 error:
 724         free(exp1);
 725         free(exp2);
 726         isl_local_space_free(ls1);
 727         isl_local_space_free(ls2);
 728         return NULL;
 729 }
 730
 731 /* Does "ls" have an explicit representation for div "div"?
 732  */
 733 int isl_local_space_div_is_known(__isl_keep isl_local_space *ls, int div)
 734 {
 735         if (!ls)
 736                 return -1;
 737         if (div < 0 || div >= ls->div->n_row)
 738                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 739                         "position out of bounds", return -1);
 740         return !isl_int_is_zero(ls->div->row[div][0]);
 741 }
 742
 743 /* Does "ls" have an explicit representation for all local variables?
 744  */
 745 isl_bool isl_local_space_divs_known(__isl_keep isl_local_space *ls)
 746 {
 747         int i;
 748
 749         if (!ls)
 750                 return isl_bool_error;
 751
 752         for (i = 0; i < ls->div->n_row; ++i)
 753                 if (isl_int_is_zero(ls->div->row[i][0]))
 754                         return isl_bool_false;
 755
 756         return isl_bool_true;
 757 }
 758
 759 __isl_give isl_local_space *isl_local_space_domain(
 760         __isl_take isl_local_space *ls)
 761 {
 762         ls = isl_local_space_drop_dims(ls, isl_dim_out,
 763                                         0, isl_local_space_dim(ls, isl_dim_out));
 764         ls = isl_local_space_cow(ls);
 765         if (!ls)
 766                 return NULL;
 767         ls->dim = isl_space_domain(ls->dim);
 768         if (!ls->dim)
 769                 return isl_local_space_free(ls);
 770         return ls;
 771 }
 772
 773 __isl_give isl_local_space *isl_local_space_range(
 774         __isl_take isl_local_space *ls)
 775 {
 776         ls = isl_local_space_drop_dims(ls, isl_dim_in,
 777                                         0, isl_local_space_dim(ls, isl_dim_in));
 778         ls = isl_local_space_cow(ls);
 779         if (!ls)
 780                 return NULL;
 781
 782         ls->dim = isl_space_range(ls->dim);
 783         if (!ls->dim)
 784                 return isl_local_space_free(ls);
 785         return ls;
 786 }
 787
 788 /* Construct a local space for a map that has the given local
 789  * space as domain and that has a zero-dimensional range.
 790  */
 791 __isl_give isl_local_space *isl_local_space_from_domain(
 792         __isl_take isl_local_space *ls)
 793 {
 794         ls = isl_local_space_cow(ls);
 795         if (!ls)
 796                 return NULL;
 797         ls->dim = isl_space_from_domain(ls->dim);
 798         if (!ls->dim)
 799                 return isl_local_space_free(ls);
 800         return ls;
 801 }
 802
 803 __isl_give isl_local_space *isl_local_space_add_dims(
 804         __isl_take isl_local_space *ls, enum isl_dim_type type, unsigned n)
 805 {
 806         int pos;
 807
 808         if (!ls)
 809                 return NULL;
 810         pos = isl_local_space_dim(ls, type);
 811         return isl_local_space_insert_dims(ls, type, pos, n);
 812 }
 813
 814 /* Remove common factor of non-constant terms and denominator.
 815  */
 816 static void normalize_div(__isl_keep isl_local_space *ls, int div)
 817 {
 818         isl_ctx *ctx = ls->div->ctx;
 819         unsigned total = ls->div->n_col - 2;
 820
 821         isl_seq_gcd(ls->div->row[div] + 2, total, &ctx->normalize_gcd);
 822         isl_int_gcd(ctx->normalize_gcd,
 823                     ctx->normalize_gcd, ls->div->row[div][0]);
 824         if (isl_int_is_one(ctx->normalize_gcd))
 825                 return;
 826
 827         isl_seq_scale_down(ls->div->row[div] + 2, ls->div->row[div] + 2,
 828                             ctx->normalize_gcd, total);
 829         isl_int_divexact(ls->div->row[div][0], ls->div->row[div][0],
 830                             ctx->normalize_gcd);
 831         isl_int_fdiv_q(ls->div->row[div][1], ls->div->row[div][1],
 832                             ctx->normalize_gcd);
 833 }
 834
 835 /* Exploit the equalities in "eq" to simplify the expressions of
 836  * the integer divisions in "ls".
 837  * The integer divisions in "ls" are assumed to appear as regular
 838  * dimensions in "eq".
 839  */
 840 __isl_give isl_local_space *isl_local_space_substitute_equalities(
 841         __isl_take isl_local_space *ls, __isl_take isl_basic_set *eq)
 842 {
 843         int i, j, k;
 844         unsigned total;
 845         unsigned n_div;
 846
 847         if (!ls || !eq)
 848                 goto error;
 849
 850         total = isl_space_dim(eq->dim, isl_dim_all);
 851         if (isl_local_space_dim(ls, isl_dim_all) != total)
 852                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 853                         "spaces don't match", goto error);
 854         total++;
 855         n_div = eq->n_div;
 856         for (i = 0; i < eq->n_eq; ++i) {
 857                 j = isl_seq_last_non_zero(eq->eq[i], total + n_div);
 858                 if (j < 0 || j == 0 || j >= total)
 859                         continue;
 860
 861                 for (k = 0; k < ls->div->n_row; ++k) {
 862                         if (isl_int_is_zero(ls->div->row[k][1 + j]))
 863                                 continue;
 864                         ls = isl_local_space_cow(ls);
 865                         if (!ls)
 866                                 goto error;
 867                         ls->div = isl_mat_cow(ls->div);
 868                         if (!ls->div)
 869                                 goto error;
 870                         isl_seq_elim(ls->div->row[k] + 1, eq->eq[i], j, total,
 871                                         &ls->div->row[k][0]);
 872                         normalize_div(ls, k);
 873                 }
 874         }
 875
 876         isl_basic_set_free(eq);
 877         return ls;
 878 error:
 879         isl_basic_set_free(eq);
 880         isl_local_space_free(ls);
 881         return NULL;
 882 }
 883
 884 /* Plug in the affine expressions "subs" of length "subs_len" (including
 885  * the denominator and the constant term) into the variable at position "pos"
 886  * of the "n" div expressions starting at "first".
 887  *
 888  * Let i be the dimension to replace and let "subs" be of the form
 889  *
 890  *      f/d
 891  *
 892  * Any integer division starting at "first" with a non-zero coefficient for i,
 893  *
 894  *      floor((a i + g)/m)
 895  *
 896  * is replaced by
 897  *
 898  *      floor((a f + d g)/(m d))
 899  */
 900 __isl_give isl_local_space *isl_local_space_substitute_seq(
 901         __isl_take isl_local_space *ls,
 902         enum isl_dim_type type, unsigned pos, isl_int *subs, int subs_len,
 903         int first, int n)
 904 {
 905         int i;
 906         isl_int v;
 907
 908         if (n == 0)
 909                 return ls;
 910         ls = isl_local_space_cow(ls);
 911         if (!ls)
 912                 return NULL;
 913         ls->div = isl_mat_cow(ls->div);
 914         if (!ls->div)
 915                 return isl_local_space_free(ls);
 916
 917         if (first + n > ls->div->n_row)
 918                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 919                         "index out of bounds", return isl_local_space_free(ls));
 920
 921         pos += isl_local_space_offset(ls, type);
 922
 923         isl_int_init(v);
 924         for (i = first; i < first + n; ++i) {
 925                 if (isl_int_is_zero(ls->div->row[i][1 + pos]))
 926                         continue;
 927                 isl_seq_substitute(ls->div->row[i], pos, subs,
 928                         ls->div->n_col, subs_len, v);
 929                 normalize_div(ls, i);
 930         }
 931         isl_int_clear(v);
 932
 933         return ls;
 934 }
 935
 936 /* Plug in "subs" for dimension "type", "pos" in the integer divisions
 937  * of "ls".
 938  *
 939  * Let i be the dimension to replace and let "subs" be of the form
 940  *
 941  *      f/d
 942  *
 943  * Any integer division with a non-zero coefficient for i,
 944  *
 945  *      floor((a i + g)/m)
 946  *
 947  * is replaced by
 948  *
 949  *      floor((a f + d g)/(m d))
 950  */
 951 __isl_give isl_local_space *isl_local_space_substitute(
 952         __isl_take isl_local_space *ls,
 953         enum isl_dim_type type, unsigned pos, __isl_keep isl_aff *subs)
 954 {
 955         ls = isl_local_space_cow(ls);
 956         if (!ls || !subs)
 957                 return isl_local_space_free(ls);
 958
 959         if (!isl_space_is_equal(ls->dim, subs->ls->dim))
 960                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 961                         "spaces don't match", return isl_local_space_free(ls));
 962         if (isl_local_space_dim(subs->ls, isl_dim_div) != 0)
 963                 isl_die(isl_local_space_get_ctx(ls), isl_error_unsupported,
 964                         "cannot handle divs yet",
 965                         return isl_local_space_free(ls));
 966
 967         return isl_local_space_substitute_seq(ls, type, pos, subs->v->el,
 968                                             subs->v->size, 0, ls->div->n_row);
 969 }
 970
 971 int isl_local_space_is_named_or_nested(__isl_keep isl_local_space *ls,
 972         enum isl_dim_type type)
 973 {
 974         if (!ls)
 975                 return -1;
 976         return isl_space_is_named_or_nested(ls->dim, type);
 977 }
 978
 979 __isl_give isl_local_space *isl_local_space_drop_dims(
 980         __isl_take isl_local_space *ls,
 981         enum isl_dim_type type, unsigned first, unsigned n)
 982 {
 983         isl_ctx *ctx;
 984
 985         if (!ls)
 986                 return NULL;
 987         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
 988                 return ls;
 989
 990         ctx = isl_local_space_get_ctx(ls);
 991         if (first + n > isl_local_space_dim(ls, type))
 992                 isl_die(ctx, isl_error_invalid, "range out of bounds",
 993                         return isl_local_space_free(ls));
 994
 995         ls = isl_local_space_cow(ls);
 996         if (!ls)
 997                 return NULL;
 998
 999         if (type == isl_dim_div) {
1000                 ls->div = isl_mat_drop_rows(ls->div, first, n);
1001         } else {
1002                 ls->dim = isl_space_drop_dims(ls->dim, type, first, n);
1003                 if (!ls->dim)
1004                         return isl_local_space_free(ls);
1005         }
1006
1007         first += 1 + isl_local_space_offset(ls, type);
1008         ls->div = isl_mat_drop_cols(ls->div, first, n);
1009         if (!ls->div)
1010                 return isl_local_space_free(ls);
1011
1012         return ls;
1013 }
1014
1015 __isl_give isl_local_space *isl_local_space_insert_dims(
1016         __isl_take isl_local_space *ls,
1017         enum isl_dim_type type, unsigned first, unsigned n)
1018 {
1019         isl_ctx *ctx;
1020
1021         if (!ls)
1022                 return NULL;
1023         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
1024                 return ls;
1025
1026         ctx = isl_local_space_get_ctx(ls);
1027         if (first > isl_local_space_dim(ls, type))
1028                 isl_die(ctx, isl_error_invalid, "position out of bounds",
1029                         return isl_local_space_free(ls));
1030
1031         ls = isl_local_space_cow(ls);
1032         if (!ls)
1033                 return NULL;
1034
1035         if (type == isl_dim_div) {
1036                 ls->div = isl_mat_insert_zero_rows(ls->div, first, n);
1037         } else {
1038                 ls->dim = isl_space_insert_dims(ls->dim, type, first, n);
1039                 if (!ls->dim)
1040                         return isl_local_space_free(ls);
1041         }
1042
1043         first += 1 + isl_local_space_offset(ls, type);
1044         ls->div = isl_mat_insert_zero_cols(ls->div, first, n);
1045         if (!ls->div)
1046                 return isl_local_space_free(ls);
1047
1048         return ls;
1049 }
1050
1051 /* Check if the constraints pointed to by "constraint" is a div
1052  * constraint corresponding to div "div" in "ls".
1053  *
1054  * That is, if div = floor(f/m), then check if the constraint is
1055  *
1056  *              f - m d >= 0
1057  * or
1058  *              -(f-(m-1)) + m d >= 0
1059  */
1060 int isl_local_space_is_div_constraint(__isl_keep isl_local_space *ls,
1061         isl_int *constraint, unsigned div)
1062 {
1063         unsigned pos;
1064
1065         if (!ls)
1066                 return -1;
1067
1068         if (isl_int_is_zero(ls->div->row[div][0]))
1069                 return 0;
1070
1071         pos = isl_local_space_offset(ls, isl_dim_div) + div;
1072
1073         if (isl_int_eq(constraint[pos], ls->div->row[div][0])) {
1074                 int neg;
1075                 isl_int_sub(ls->div->row[div][1],
1076                                 ls->div->row[div][1], ls->div->row[div][0]);
1077                 isl_int_add_ui(ls->div->row[div][1], ls->div->row[div][1], 1);
1078                 neg = isl_seq_is_neg(constraint, ls->div->row[div]+1, pos);
1079                 isl_int_sub_ui(ls->div->row[div][1], ls->div->row[div][1], 1);
1080                 isl_int_add(ls->div->row[div][1],
1081                                 ls->div->row[div][1], ls->div->row[div][0]);
1082                 if (!neg)
1083                         return 0;
1084                 if (isl_seq_first_non_zero(constraint+pos+1,
1085                                             ls->div->n_row-div-1) != -1)
1086                         return 0;
1087         } else if (isl_int_abs_eq(constraint[pos], ls->div->row[div][0])) {
1088                 if (!isl_seq_eq(constraint, ls->div->row[div]+1, pos))
1089                         return 0;
1090                 if (isl_seq_first_non_zero(constraint+pos+1,
1091                                             ls->div->n_row-div-1) != -1)
1092                         return 0;
1093         } else
1094                 return 0;
1095
1096         return 1;
1097 }
1098
1099 /*
1100  * Set active[i] to 1 if the dimension at position i is involved
1101  * in the linear expression l.
1102  */
1103 int *isl_local_space_get_active(__isl_keep isl_local_space *ls, isl_int *l)
1104 {
1105         int i, j;
1106         isl_ctx *ctx;
1107         int *active = NULL;
1108         unsigned total;
1109         unsigned offset;
1110
1111         ctx = isl_local_space_get_ctx(ls);
1112         total = isl_local_space_dim(ls, isl_dim_all);
1113         active = isl_calloc_array(ctx, int, total);
1114         if (total && !active)
1115                 return NULL;
1116
1117         for (i = 0; i < total; ++i)
1118                 active[i] = !isl_int_is_zero(l[i]);
1119
1120         offset = isl_local_space_offset(ls, isl_dim_div) - 1;
1121         for (i = ls->div->n_row - 1; i >= 0; --i) {
1122                 if (!active[offset + i])
1123                         continue;
1124                 for (j = 0; j < total; ++j)
1125                         active[j] |= !isl_int_is_zero(ls->div->row[i][2 + j]);
1126         }
1127
1128         return active;
1129 }
1130
1131 /* Given a local space "ls" of a set, create a local space
1132  * for the lift of the set.  In particular, the result
1133  * is of the form [dim -> local[..]], with ls->div->n_row variables in the
1134  * range of the wrapped map.
1135  */
1136 __isl_give isl_local_space *isl_local_space_lift(
1137         __isl_take isl_local_space *ls)
1138 {
1139         ls = isl_local_space_cow(ls);
1140         if (!ls)
1141                 return NULL;
1142
1143         ls->dim = isl_space_lift(ls->dim, ls->div->n_row);
1144         ls->div = isl_mat_drop_rows(ls->div, 0, ls->div->n_row);
1145         if (!ls->dim || !ls->div)
1146                 return isl_local_space_free(ls);
1147
1148         return ls;
1149 }
1150
1151 /* Construct a basic map that maps a set living in local space "ls"
1152  * to the corresponding lifted local space.
1153  */
1154 __isl_give isl_basic_map *isl_local_space_lifting(
1155         __isl_take isl_local_space *ls)
1156 {
1157         isl_basic_map *lifting;
1158         isl_basic_set *bset;
1159
1160         if (!ls)
1161                 return NULL;
1162         if (!isl_local_space_is_set(ls))
1163                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1164                         "lifting only defined on set spaces", goto error);
1165
1166         bset = isl_basic_set_from_local_space(ls);
1167         lifting = isl_basic_set_unwrap(isl_basic_set_lift(bset));
1168         lifting = isl_basic_map_domain_map(lifting);
1169         lifting = isl_basic_map_reverse(lifting);
1170
1171         return lifting;
1172 error:
1173         isl_local_space_free(ls);
1174         return NULL;
1175 }
1176
1177 /* Compute the preimage of "ls" under the function represented by "ma".
1178  * In other words, plug in "ma" in "ls".  The result is a local space
1179  * that is part of the domain space of "ma".
1180  *
1181  * If the divs in "ls" are represented as
1182  *
1183  *      floor((a_i(p) + b_i x + c_i(divs))/n_i)
1184  *
1185  * and ma is represented by
1186  *
1187  *      x = D(p) + F(y) + G(divs')
1188  *
1189  * then the resulting divs are
1190  *
1191  *      floor((a_i(p) + b_i D(p) + b_i F(y) + B_i G(divs') + c_i(divs))/n_i)
1192  *
1193  * We first copy over the divs from "ma" and then
1194  * we add the modified divs from "ls".
1195  */
1196 __isl_give isl_local_space *isl_local_space_preimage_multi_aff(
1197         __isl_take isl_local_space *ls, __isl_take isl_multi_aff *ma)
1198 {
1199         int i;
1200         isl_space *space;
1201         isl_local_space *res = NULL;
1202         int n_div_ls, n_div_ma;
1203         isl_int f, c1, c2, g;
1204
1205         ma = isl_multi_aff_align_divs(ma);
1206         if (!ls || !ma)
1207                 goto error;
1208         if (!isl_space_is_range_internal(ls->dim, ma->space))
1209                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1210                         "spaces don't match", goto error);
1211
1212         n_div_ls = isl_local_space_dim(ls, isl_dim_div);
1213         n_div_ma = ma->n ? isl_aff_dim(ma->p[0], isl_dim_div) : 0;
1214
1215         space = isl_space_domain(isl_multi_aff_get_space(ma));
1216         res = isl_local_space_alloc(space, n_div_ma + n_div_ls);
1217         if (!res)
1218                 goto error;
1219
1220         if (n_div_ma) {
1221                 isl_mat_free(res->div);
1222                 res->div = isl_mat_copy(ma->p[0]->ls->div);
1223                 res->div = isl_mat_add_zero_cols(res->div, n_div_ls);
1224                 res->div = isl_mat_add_rows(res->div, n_div_ls);
1225                 if (!res->div)
1226                         goto error;
1227         }
1228
1229         isl_int_init(f);
1230         isl_int_init(c1);
1231         isl_int_init(c2);
1232         isl_int_init(g);
1233
1234         for (i = 0; i < ls->div->n_row; ++i) {
1235                 if (isl_int_is_zero(ls->div->row[i][0])) {
1236                         isl_int_set_si(res->div->row[n_div_ma + i][0], 0);
1237                         continue;
1238                 }
1239                 isl_seq_preimage(res->div->row[n_div_ma + i], ls->div->row[i],
1240                                 ma, 0, 0, n_div_ma, n_div_ls, f, c1, c2, g, 1);
1241                 normalize_div(res, n_div_ma + i);
1242         }
1243
1244         isl_int_clear(f);
1245         isl_int_clear(c1);
1246         isl_int_clear(c2);
1247         isl_int_clear(g);
1248
1249         isl_local_space_free(ls);
1250         isl_multi_aff_free(ma);
1251         return res;
1252 error:
1253         isl_local_space_free(ls);
1254         isl_multi_aff_free(ma);
1255         isl_local_space_free(res);
1256         return NULL;
1257 }
1258
1259 /* Move the "n" dimensions of "src_type" starting at "src_pos" of "ls"
1260  * to dimensions of "dst_type" at "dst_pos".
1261  *
1262  * Moving to/from local dimensions is not allowed.
1263  * We currently assume that the dimension type changes.
1264  */
1265 __isl_give isl_local_space *isl_local_space_move_dims(
1266         __isl_take isl_local_space *ls,
1267         enum isl_dim_type dst_type, unsigned dst_pos,
1268         enum isl_dim_type src_type, unsigned src_pos, unsigned n)
1269 {
1270         unsigned g_dst_pos;
1271         unsigned g_src_pos;
1272
1273         if (!ls)
1274                 return NULL;
1275         if (n == 0 &&
1276             !isl_local_space_is_named_or_nested(ls, src_type) &&
1277             !isl_local_space_is_named_or_nested(ls, dst_type))
1278                 return ls;
1279
1280         if (src_pos + n > isl_local_space_dim(ls, src_type))
1281                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1282                         "range out of bounds", return isl_local_space_free(ls));
1283         if (dst_pos > isl_local_space_dim(ls, dst_type))
1284                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1285                         "position out of bounds",
1286                         return isl_local_space_free(ls));
1287         if (src_type == isl_dim_div)
1288                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1289                         "cannot move divs", return isl_local_space_free(ls));
1290         if (dst_type == isl_dim_div)
1291                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
1292                         "cannot move to divs", return isl_local_space_free(ls));
1293         if (dst_type == src_type && dst_pos == src_pos)
1294                 return ls;
1295         if (dst_type == src_type)
1296                 isl_die(isl_local_space_get_ctx(ls), isl_error_unsupported,
1297                         "moving dims within the same type not supported",
1298                         return isl_local_space_free(ls));
1299
1300         ls = isl_local_space_cow(ls);
1301         if (!ls)
1302                 return NULL;
1303
1304         g_src_pos = 1 + isl_local_space_offset(ls, src_type) + src_pos;
1305         g_dst_pos = 1 + isl_local_space_offset(ls, dst_type) + dst_pos;
1306         if (dst_type > src_type)
1307                 g_dst_pos -= n;
1308         ls->div = isl_mat_move_cols(ls->div, g_dst_pos, g_src_pos, n);
1309         if (!ls->div)
1310                 return isl_local_space_free(ls);
1311         ls->dim = isl_space_move_dims(ls->dim, dst_type, dst_pos,
1312                                         src_type, src_pos, n);
1313         if (!ls->dim)
1314                 return isl_local_space_free(ls);
1315
1316         return ls;
1317 }
1318
1319 /* Remove any internal structure of the domain of "ls".
1320  * If there is any such internal structure in the input,
1321  * then the name of the corresponding space is also removed.
1322  */
1323 __isl_give isl_local_space *isl_local_space_flatten_domain(
1324         __isl_take isl_local_space *ls)
1325 {
1326         if (!ls)
1327                 return NULL;
1328
1329         if (!ls->dim->nested[0])
1330                 return ls;
1331
1332         ls = isl_local_space_cow(ls);
1333         if (!ls)
1334                 return NULL;
1335
1336         ls->dim = isl_space_flatten_domain(ls->dim);
1337         if (!ls->dim)
1338                 return isl_local_space_free(ls);
1339
1340         return ls;
1341 }
1342
1343 /* Remove any internal structure of the range of "ls".
1344  * If there is any such internal structure in the input,
1345  * then the name of the corresponding space is also removed.
1346  */
1347 __isl_give isl_local_space *isl_local_space_flatten_range(
1348         __isl_take isl_local_space *ls)
1349 {
1350         if (!ls)
1351                 return NULL;
1352
1353         if (!ls->dim->nested[1])
1354                 return ls;
1355
1356         ls = isl_local_space_cow(ls);
1357         if (!ls)
1358                 return NULL;
1359
1360         ls->dim = isl_space_flatten_range(ls->dim);
1361         if (!ls->dim)
1362                 return isl_local_space_free(ls);
1363
1364         return ls;
1365 }
1366
1367 /* Given the local space "ls" of a map, return the local space of a set
1368  * that lives in a space that wraps the space of "ls" and that has
1369  * the same divs.
1370  */
1371 __isl_give isl_local_space *isl_local_space_wrap(__isl_take isl_local_space *ls)
1372 {
1373         ls = isl_local_space_cow(ls);
1374         if (!ls)
1375                 return NULL;
1376
1377         ls->dim = isl_space_wrap(ls->dim);
1378         if (!ls->dim)
1379                 return isl_local_space_free(ls);
1380
1381         return ls;
1382 }