isl_local_space.c

   1 /*
   2  * Copyright 2011      INRIA Saclay
   3  *
   4  * Use of this software is governed by the GNU LGPLv2.1 license
   5  *
   6  * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
   7  * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
   8  * 91893 Orsay, France
   9  */
  10
  11 #include <isl_ctx_private.h>
  12 #include <isl_map_private.h>
  13 #include <isl_local_space_private.h>
  14 #include <isl_dim_private.h>
  15 #include <isl_mat_private.h>
  16 #include <isl/seq.h>
  17
  18 isl_ctx *isl_local_space_get_ctx(__isl_keep isl_local_space *ls)
  19 {
  20         return ls ? ls->dim->ctx : NULL;
  21 }
  22
  23 __isl_give isl_local_space *isl_local_space_alloc_div(__isl_take isl_dim *dim,
  24         __isl_take isl_mat *div)
  25 {
  26         isl_ctx *ctx;
  27         isl_local_space *ls = NULL;
  28
  29         if (!dim)
  30                 goto error;
  31
  32         ctx = isl_dim_get_ctx(dim);
  33         ls = isl_calloc_type(ctx, struct isl_local_space);
  34         if (!ls)
  35                 goto error;
  36
  37         ls->ref = 1;
  38         ls->dim = dim;
  39         ls->div = div;
  40
  41         return ls;
  42 error:
  43         isl_dim_free(dim);
  44         isl_local_space_free(ls);
  45         return NULL;
  46 }
  47
  48 __isl_give isl_local_space *isl_local_space_alloc(__isl_take isl_dim *dim,
  49         unsigned n_div)
  50 {
  51         isl_ctx *ctx;
  52         isl_mat *div;
  53         unsigned total;
  54
  55         if (!dim)
  56                 return NULL;
  57
  58         total = isl_dim_total(dim);
  59
  60         ctx = isl_dim_get_ctx(dim);
  61         div = isl_mat_alloc(ctx, n_div, 1 + 1 + total + n_div);
  62         return isl_local_space_alloc_div(dim, div);
  63 }
  64
  65 __isl_give isl_local_space *isl_local_space_from_dim(__isl_take isl_dim *dim)
  66 {
  67         return isl_local_space_alloc(dim, 0);
  68 }
  69
  70 __isl_give isl_local_space *isl_local_space_copy(__isl_keep isl_local_space *ls)
  71 {
  72         if (!ls)
  73                 return NULL;
  74
  75         ls->ref++;
  76         return ls;
  77 }
  78
  79 __isl_give isl_local_space *isl_local_space_dup(__isl_keep isl_local_space *ls)
  80 {
  81         if (!ls)
  82                 return NULL;
  83
  84         return isl_local_space_alloc_div(isl_dim_copy(ls->dim),
  85                                          isl_mat_copy(ls->div));
  86
  87 }
  88
  89 __isl_give isl_local_space *isl_local_space_cow(__isl_take isl_local_space *ls)
  90 {
  91         if (!ls)
  92                 return NULL;
  93
  94         if (ls->ref == 1)
  95                 return ls;
  96         ls->ref--;
  97         return isl_local_space_dup(ls);
  98 }
  99
 100 void *isl_local_space_free(__isl_take isl_local_space *ls)
 101 {
 102         if (!ls)
 103                 return NULL;
 104
 105         if (--ls->ref > 0)
 106                 return NULL;
 107
 108         isl_dim_free(ls->dim);
 109         isl_mat_free(ls->div);
 110
 111         free(ls);
 112
 113         return NULL;
 114 }
 115
 116 /* Return true if the two local spaces are identical, with identical
 117  * expressions for the integer divisions.
 118  */
 119 int isl_local_space_is_equal(__isl_keep isl_local_space *ls1,
 120         __isl_keep isl_local_space *ls2)
 121 {
 122         int equal;
 123
 124         if (!ls1 || !ls2)
 125                 return -1;
 126
 127         equal = isl_dim_equal(ls1->dim, ls2->dim);
 128         if (equal < 0 || !equal)
 129                 return equal;
 130
 131         if (!isl_local_space_divs_known(ls1))
 132                 return 0;
 133         if (!isl_local_space_divs_known(ls2))
 134                 return 0;
 135
 136         return isl_mat_is_equal(ls1->div, ls2->div);
 137 }
 138
 139 int isl_local_space_dim(__isl_keep isl_local_space *ls,
 140         enum isl_dim_type type)
 141 {
 142         if (!ls)
 143                 return 0;
 144         if (type == isl_dim_div)
 145                 return ls->div->n_row;
 146         if (type == isl_dim_all)
 147                 return isl_dim_size(ls->dim, isl_dim_all) + ls->div->n_row;
 148         return isl_dim_size(ls->dim, type);
 149 }
 150
 151 unsigned isl_local_space_offset(__isl_keep isl_local_space *ls,
 152         enum isl_dim_type type)
 153 {
 154         isl_dim *dim;
 155
 156         if (!ls)
 157                 return 0;
 158
 159         dim = ls->dim;
 160         switch (type) {
 161         case isl_dim_cst:       return 0;
 162         case isl_dim_param:     return 1;
 163         case isl_dim_in:        return 1 + dim->nparam;
 164         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
 165         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
 166         default:                return 0;
 167         }
 168 }
 169
 170 const char *isl_local_space_get_dim_name(__isl_keep isl_local_space *ls,
 171         enum isl_dim_type type, unsigned pos)
 172 {
 173         return ls ? isl_dim_get_name(ls->dim, type, pos) : NULL;
 174 }
 175
 176 __isl_give isl_div *isl_local_space_get_div(__isl_keep isl_local_space *ls,
 177         int pos)
 178 {
 179         isl_basic_map *bmap;
 180
 181         if (!ls)
 182                 return NULL;
 183
 184         if (pos < 0 || pos >= ls->div->n_row)
 185                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 186                         "index out of bounds", return NULL);
 187
 188         if (isl_int_is_zero(ls->div->row[pos][0]))
 189                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 190                         "expression of div unknown", return NULL);
 191
 192         bmap = isl_basic_map_from_local_space(isl_local_space_copy(ls));
 193         return isl_basic_map_div(bmap, pos);
 194 }
 195
 196 __isl_give isl_dim *isl_local_space_get_dim(__isl_keep isl_local_space *ls)
 197 {
 198         if (!ls)
 199                 return NULL;
 200
 201         return isl_dim_copy(ls->dim);
 202 }
 203
 204 __isl_give isl_local_space *isl_local_space_set_dim_name(
 205         __isl_take isl_local_space *ls,
 206         enum isl_dim_type type, unsigned pos, const char *s)
 207 {
 208         ls = isl_local_space_cow(ls);
 209         if (!ls)
 210                 return NULL;
 211         ls->dim = isl_dim_set_name(ls->dim, type, pos, s);
 212         if (!ls->dim)
 213                 return isl_local_space_free(ls);
 214
 215         return ls;
 216 }
 217
 218 __isl_give isl_local_space *isl_local_space_add_div(
 219         __isl_take isl_local_space *ls, __isl_take isl_vec *div)
 220 {
 221         ls = isl_local_space_cow(ls);
 222         if (!ls || !div)
 223                 goto error;
 224
 225         if (ls->div->n_col != div->size)
 226                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 227                         "incompatible dimensions", goto error);
 228
 229         ls->div = isl_mat_add_zero_cols(ls->div, 1);
 230         ls->div = isl_mat_add_rows(ls->div, 1);
 231         if (!ls->div)
 232                 goto error;
 233
 234         isl_seq_cpy(ls->div->row[ls->div->n_row - 1], div->el, div->size);
 235         isl_int_set_si(ls->div->row[ls->div->n_row - 1][div->size], 0);
 236
 237         isl_vec_free(div);
 238         return ls;
 239 error:
 240         isl_local_space_free(ls);
 241         isl_vec_free(div);
 242         return NULL;
 243 }
 244
 245 __isl_give isl_local_space *isl_local_space_replace_divs(
 246         __isl_take isl_local_space *ls, __isl_take isl_mat *div)
 247 {
 248         ls = isl_local_space_cow(ls);
 249
 250         if (!ls || !div)
 251                 goto error;
 252
 253         isl_mat_free(ls->div);
 254         ls->div = div;
 255         return ls;
 256 error:
 257         isl_mat_free(div);
 258         isl_local_space_free(ls);
 259         return NULL;
 260 }
 261
 262 /* Copy row "s" of "src" to row "d" of "dst", applying the expansion
 263  * defined by "exp".
 264  */
 265 static void expand_row(__isl_keep isl_mat *dst, int d,
 266         __isl_keep isl_mat *src, int s, int *exp)
 267 {
 268         int i;
 269         unsigned c = src->n_col - src->n_row;
 270
 271         isl_seq_cpy(dst->row[d], src->row[s], c);
 272         isl_seq_clr(dst->row[d] + c, dst->n_col - c);
 273
 274         for (i = 0; i < s; ++i)
 275                 isl_int_set(dst->row[d][c + exp[i]], src->row[s][c + i]);
 276 }
 277
 278 /* Compare (known) divs.
 279  * Return non-zero if at least one of the two divs is unknown.
 280  */
 281 static int cmp_row(__isl_keep isl_mat *div, int i, int j)
 282 {
 283         int li, lj;
 284
 285         if (isl_int_is_zero(div->row[j][0]))
 286                 return -1;
 287         if (isl_int_is_zero(div->row[i][0]))
 288                 return 1;
 289
 290         li = isl_seq_last_non_zero(div->row[i], div->n_col);
 291         lj = isl_seq_last_non_zero(div->row[j], div->n_col);
 292
 293         if (li != lj)
 294                 return li - lj;
 295
 296         return isl_seq_cmp(div->row[i], div->row[j], div->n_col);
 297 }
 298
 299 /* Combine the two lists of divs into a single list.
 300  * For each row i in div1, exp1[i] is set to the position of the corresponding
 301  * row in the result.  Similarly for div2 and exp2.
 302  * This function guarantees
 303  *      exp1[i] >= i
 304  *      exp1[i+1] > exp1[i]
 305  * For optimal merging, the two input list should have been sorted.
 306  */
 307 __isl_give isl_mat *isl_merge_divs(__isl_keep isl_mat *div1,
 308         __isl_keep isl_mat *div2, int *exp1, int *exp2)
 309 {
 310         int i, j, k;
 311         isl_mat *div = NULL;
 312         unsigned d = div1->n_col - div1->n_row;
 313
 314         div = isl_mat_alloc(div1->ctx, 1 + div1->n_row + div2->n_row,
 315                                 d + div1->n_row + div2->n_row);
 316         if (!div)
 317                 return NULL;
 318
 319         for (i = 0, j = 0, k = 0; i < div1->n_row && j < div2->n_row; ++k) {
 320                 int cmp;
 321
 322                 expand_row(div, k, div1, i, exp1);
 323                 expand_row(div, k + 1, div2, j, exp2);
 324
 325                 cmp = cmp_row(div, k, k + 1);
 326                 if (cmp == 0) {
 327                         exp1[i++] = k;
 328                         exp2[j++] = k;
 329                 } else if (cmp < 0) {
 330                         exp1[i++] = k;
 331                 } else {
 332                         exp2[j++] = k;
 333                         isl_seq_cpy(div->row[k], div->row[k + 1], div->n_col);
 334                 }
 335         }
 336         for (; i < div1->n_row; ++i, ++k) {
 337                 expand_row(div, k, div1, i, exp1);
 338                 exp1[i] = k;
 339         }
 340         for (; j < div2->n_row; ++j, ++k) {
 341                 expand_row(div, k, div2, j, exp2);
 342                 exp2[j] = k;
 343         }
 344
 345         div->n_row = k;
 346         div->n_col = d + k;
 347
 348         return div;
 349 }
 350
 351 int isl_local_space_divs_known(__isl_keep isl_local_space *ls)
 352 {
 353         int i;
 354
 355         if (!ls)
 356                 return -1;
 357
 358         for (i = 0; i < ls->div->n_row; ++i)
 359                 if (isl_int_is_zero(ls->div->row[i][0]))
 360                         return 0;
 361
 362         return 1;
 363 }
 364
 365 /* Construct a local space for a map that has the given local
 366  * space as domain and that has a zero-dimensional range.
 367  */
 368 __isl_give isl_local_space *isl_local_space_from_domain(
 369         __isl_take isl_local_space *ls)
 370 {
 371         ls = isl_local_space_cow(ls);
 372         if (!ls)
 373                 return NULL;
 374         ls->dim = isl_dim_from_domain(ls->dim);
 375         if (!ls->dim)
 376                 return isl_local_space_free(ls);
 377         return ls;
 378 }
 379
 380 __isl_give isl_local_space *isl_local_space_add_dims(
 381         __isl_take isl_local_space *ls, enum isl_dim_type type, unsigned n)
 382 {
 383         int pos;
 384
 385         if (!ls)
 386                 return NULL;
 387         pos = isl_local_space_dim(ls, type);
 388         return isl_local_space_insert_dims(ls, type, pos, n);
 389 }
 390
 391 /* Remove common factor of non-constant terms and denominator.
 392  */
 393 static void normalize_div(__isl_keep isl_local_space *ls, int div)
 394 {
 395         isl_ctx *ctx = ls->div->ctx;
 396         unsigned total = ls->div->n_col - 2;
 397
 398         isl_seq_gcd(ls->div->row[div] + 2, total, &ctx->normalize_gcd);
 399         isl_int_gcd(ctx->normalize_gcd,
 400                     ctx->normalize_gcd, ls->div->row[div][0]);
 401         if (isl_int_is_one(ctx->normalize_gcd))
 402                 return;
 403
 404         isl_seq_scale_down(ls->div->row[div] + 2, ls->div->row[div] + 2,
 405                             ctx->normalize_gcd, total);
 406         isl_int_divexact(ls->div->row[div][0], ls->div->row[div][0],
 407                             ctx->normalize_gcd);
 408         isl_int_fdiv_q(ls->div->row[div][1], ls->div->row[div][1],
 409                             ctx->normalize_gcd);
 410 }
 411
 412 /* Exploit the equalities in "eq" to simplify the expressions of
 413  * the integer divisions in "ls".
 414  * The integer divisions in "ls" are assumed to appear as regular
 415  * dimensions in "eq".
 416  */
 417 __isl_give isl_local_space *isl_local_space_substitute_equalities(
 418         __isl_take isl_local_space *ls, __isl_take isl_basic_set *eq)
 419 {
 420         int i, j, k;
 421         unsigned total;
 422         unsigned n_div;
 423
 424         ls = isl_local_space_cow(ls);
 425         if (!ls || !eq)
 426                 goto error;
 427
 428         total = isl_dim_total(eq->dim);
 429         if (isl_local_space_dim(ls, isl_dim_all) != total)
 430                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 431                         "dimensions don't match", goto error);
 432         total++;
 433         n_div = eq->n_div;
 434         for (i = 0; i < eq->n_eq; ++i) {
 435                 j = isl_seq_last_non_zero(eq->eq[i], total + n_div);
 436                 if (j < 0 || j == 0 || j >= total)
 437                         continue;
 438
 439                 for (k = 0; k < ls->div->n_row; ++k) {
 440                         if (isl_int_is_zero(ls->div->row[k][1 + j]))
 441                                 continue;
 442                         isl_seq_elim(ls->div->row[k] + 1, eq->eq[i], j, total,
 443                                         &ls->div->row[k][0]);
 444                         normalize_div(ls, k);
 445                 }
 446         }
 447
 448         isl_basic_set_free(eq);
 449         return ls;
 450 error:
 451         isl_basic_set_free(eq);
 452         isl_local_space_free(ls);
 453         return NULL;
 454 }
 455
 456 int isl_local_space_is_named_or_nested(__isl_keep isl_local_space *ls,
 457         enum isl_dim_type type)
 458 {
 459         if (!ls)
 460                 return -1;
 461         return isl_dim_is_named_or_nested(ls->dim, type);
 462 }
 463
 464 __isl_give isl_local_space *isl_local_space_drop_dims(
 465         __isl_take isl_local_space *ls,
 466         enum isl_dim_type type, unsigned first, unsigned n)
 467 {
 468         isl_ctx *ctx;
 469
 470         if (!ls)
 471                 return NULL;
 472         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
 473                 return ls;
 474
 475         ctx = isl_local_space_get_ctx(ls);
 476         if (first + n > isl_local_space_dim(ls, type))
 477                 isl_die(ctx, isl_error_invalid, "range out of bounds",
 478                         return isl_local_space_free(ls));
 479
 480         ls = isl_local_space_cow(ls);
 481         if (!ls)
 482                 return NULL;
 483
 484         if (type == isl_dim_div) {
 485                 ls->div = isl_mat_drop_rows(ls->div, first, n);
 486         } else {
 487                 ls->dim = isl_dim_drop(ls->dim, type, first, n);
 488                 if (!ls->dim)
 489                         return isl_local_space_free(ls);
 490         }
 491
 492         first += 1 + isl_local_space_offset(ls, type);
 493         ls->div = isl_mat_drop_cols(ls->div, first, n);
 494         if (!ls->div)
 495                 return isl_local_space_free(ls);
 496
 497         return ls;
 498 }
 499
 500 __isl_give isl_local_space *isl_local_space_insert_dims(
 501         __isl_take isl_local_space *ls,
 502         enum isl_dim_type type, unsigned first, unsigned n)
 503 {
 504         isl_ctx *ctx;
 505
 506         if (!ls)
 507                 return NULL;
 508         if (n == 0 && !isl_local_space_is_named_or_nested(ls, type))
 509                 return ls;
 510
 511         ctx = isl_local_space_get_ctx(ls);
 512         if (first > isl_local_space_dim(ls, type))
 513                 isl_die(ctx, isl_error_invalid, "position out of bounds",
 514                         return isl_local_space_free(ls));
 515
 516         ls = isl_local_space_cow(ls);
 517         if (!ls)
 518                 return NULL;
 519
 520         if (type == isl_dim_div) {
 521                 ls->div = isl_mat_insert_zero_rows(ls->div, first, n);
 522         } else {
 523                 ls->dim = isl_dim_insert(ls->dim, type, first, n);
 524                 if (!ls->dim)
 525                         return isl_local_space_free(ls);
 526         }
 527
 528         first += 1 + isl_local_space_offset(ls, type);
 529         ls->div = isl_mat_insert_zero_cols(ls->div, first, n);
 530         if (!ls->div)
 531                 return isl_local_space_free(ls);
 532
 533         return ls;
 534 }