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         return isl_mat_is_equal(ls1->div, ls2->div);
 132 }
 133
 134 int isl_local_space_dim(__isl_keep isl_local_space *ls,
 135         enum isl_dim_type type)
 136 {
 137         if (!ls)
 138                 return 0;
 139         if (type == isl_dim_div)
 140                 return ls->div->n_row;
 141         if (type == isl_dim_all)
 142                 return isl_dim_size(ls->dim, isl_dim_all) + ls->div->n_row;
 143         return isl_dim_size(ls->dim, type);
 144 }
 145
 146 unsigned isl_local_space_offset(__isl_keep isl_local_space *ls,
 147         enum isl_dim_type type)
 148 {
 149         isl_dim *dim;
 150
 151         if (!ls)
 152                 return 0;
 153
 154         dim = ls->dim;
 155         switch (type) {
 156         case isl_dim_cst:       return 0;
 157         case isl_dim_param:     return 1;
 158         case isl_dim_in:        return 1 + dim->nparam;
 159         case isl_dim_out:       return 1 + dim->nparam + dim->n_in;
 160         case isl_dim_div:       return 1 + dim->nparam + dim->n_in + dim->n_out;
 161         default:                return 0;
 162         }
 163 }
 164
 165 const char *isl_local_space_get_dim_name(__isl_keep isl_local_space *ls,
 166         enum isl_dim_type type, unsigned pos)
 167 {
 168         return ls ? isl_dim_get_name(ls->dim, type, pos) : NULL;
 169 }
 170
 171 __isl_give isl_div *isl_local_space_get_div(__isl_keep isl_local_space *ls,
 172         int pos)
 173 {
 174         isl_basic_map *bmap;
 175
 176         if (!ls)
 177                 return NULL;
 178
 179         if (pos < 0 || pos >= ls->div->n_row)
 180                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 181                         "index out of bounds", return NULL);
 182
 183         bmap = isl_basic_map_from_local_space(isl_local_space_copy(ls));
 184         return isl_basic_map_div(bmap, pos);
 185 }
 186
 187 __isl_give isl_dim *isl_local_space_get_dim(__isl_keep isl_local_space *ls)
 188 {
 189         if (!ls)
 190                 return NULL;
 191
 192         return isl_dim_copy(ls->dim);
 193 }
 194
 195 __isl_give isl_local_space *isl_local_space_set_dim_name(
 196         __isl_take isl_local_space *ls,
 197         enum isl_dim_type type, unsigned pos, const char *s)
 198 {
 199         ls = isl_local_space_cow(ls);
 200         if (!ls)
 201                 return NULL;
 202         ls->dim = isl_dim_set_name(ls->dim, type, pos, s);
 203         if (!ls->dim)
 204                 return isl_local_space_free(ls);
 205
 206         return ls;
 207 }
 208
 209 __isl_give isl_local_space *isl_local_space_add_div(
 210         __isl_take isl_local_space *ls, __isl_take isl_vec *div)
 211 {
 212         ls = isl_local_space_cow(ls);
 213         if (!ls || !div)
 214                 goto error;
 215
 216         if (ls->div->n_col != div->size)
 217                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 218                         "incompatible dimensions", goto error);
 219
 220         ls->div = isl_mat_add_zero_cols(ls->div, 1);
 221         ls->div = isl_mat_add_rows(ls->div, 1);
 222         if (!ls->div)
 223                 goto error;
 224
 225         isl_seq_cpy(ls->div->row[ls->div->n_row - 1], div->el, div->size);
 226         isl_int_set_si(ls->div->row[ls->div->n_row - 1][div->size], 0);
 227
 228         isl_vec_free(div);
 229         return ls;
 230 error:
 231         isl_local_space_free(ls);
 232         isl_vec_free(div);
 233         return NULL;
 234 }
 235
 236 __isl_give isl_local_space *isl_local_space_replace_divs(
 237         __isl_take isl_local_space *ls, __isl_take isl_mat *div)
 238 {
 239         ls = isl_local_space_cow(ls);
 240
 241         if (!ls || !div)
 242                 goto error;
 243
 244         isl_mat_free(ls->div);
 245         ls->div = div;
 246         return ls;
 247 error:
 248         isl_mat_free(div);
 249         isl_local_space_free(ls);
 250         return NULL;
 251 }
 252
 253 /* Copy row "s" of "src" to row "d" of "dst", applying the expansion
 254  * defined by "exp".
 255  */
 256 static void expand_row(__isl_keep isl_mat *dst, int d,
 257         __isl_keep isl_mat *src, int s, int *exp)
 258 {
 259         int i;
 260         unsigned c = src->n_col - src->n_row;
 261
 262         isl_seq_cpy(dst->row[d], src->row[s], c);
 263         isl_seq_clr(dst->row[d] + c, dst->n_col - c);
 264
 265         for (i = 0; i < s; ++i)
 266                 isl_int_set(dst->row[d][c + exp[i]], src->row[s][c + i]);
 267 }
 268
 269 /* Compare (known) divs.
 270  * Return non-zero if at least one of the two divs is unknown.
 271  */
 272 static int cmp_row(__isl_keep isl_mat *div, int i, int j)
 273 {
 274         int li, lj;
 275
 276         if (isl_int_is_zero(div->row[j][0]))
 277                 return -1;
 278         if (isl_int_is_zero(div->row[i][0]))
 279                 return 1;
 280
 281         li = isl_seq_last_non_zero(div->row[i], div->n_col);
 282         lj = isl_seq_last_non_zero(div->row[j], div->n_col);
 283
 284         if (li != lj)
 285                 return li - lj;
 286
 287         return isl_seq_cmp(div->row[i], div->row[j], div->n_col);
 288 }
 289
 290 /* Combine the two lists of divs into a single list.
 291  * For each row i in div1, exp1[i] is set to the position of the corresponding
 292  * row in the result.  Similarly for div2 and exp2.
 293  * This function guarantees
 294  *      exp1[i] >= i
 295  *      exp1[i+1] > exp1[i]
 296  * For optimal merging, the two input list should have been sorted.
 297  */
 298 __isl_give isl_mat *isl_merge_divs(__isl_keep isl_mat *div1,
 299         __isl_keep isl_mat *div2, int *exp1, int *exp2)
 300 {
 301         int i, j, k;
 302         isl_mat *div = NULL;
 303         unsigned d = div1->n_col - div1->n_row;
 304
 305         div = isl_mat_alloc(div1->ctx, 1 + div1->n_row + div2->n_row,
 306                                 d + div1->n_row + div2->n_row);
 307         if (!div)
 308                 return NULL;
 309
 310         for (i = 0, j = 0, k = 0; i < div1->n_row && j < div2->n_row; ++k) {
 311                 int cmp;
 312
 313                 expand_row(div, k, div1, i, exp1);
 314                 expand_row(div, k + 1, div2, j, exp2);
 315
 316                 cmp = cmp_row(div, k, k + 1);
 317                 if (cmp == 0) {
 318                         exp1[i++] = k;
 319                         exp2[j++] = k;
 320                 } else if (cmp < 0) {
 321                         exp1[i++] = k;
 322                 } else {
 323                         exp2[j++] = k;
 324                         isl_seq_cpy(div->row[k], div->row[k + 1], div->n_col);
 325                 }
 326         }
 327         for (; i < div1->n_row; ++i, ++k) {
 328                 expand_row(div, k, div1, i, exp1);
 329                 exp1[i] = k;
 330         }
 331         for (; j < div2->n_row; ++j, ++k) {
 332                 expand_row(div, k, div2, j, exp2);
 333                 exp2[j] = k;
 334         }
 335
 336         div->n_row = k;
 337         div->n_col = d + k;
 338
 339         return div;
 340 }
 341
 342 int isl_local_space_divs_known(__isl_keep isl_local_space *ls)
 343 {
 344         int i;
 345
 346         if (!ls)
 347                 return -1;
 348
 349         for (i = 0; i < ls->div->n_row; ++i)
 350                 if (isl_int_is_zero(ls->div->row[i][0]))
 351                         return 0;
 352
 353         return 1;
 354 }
 355
 356 /* Construct a local space for a map that has the given local
 357  * space as domain and that has a zero-dimensional range.
 358  */
 359 __isl_give isl_local_space *isl_local_space_from_domain(
 360         __isl_take isl_local_space *ls)
 361 {
 362         ls = isl_local_space_cow(ls);
 363         if (!ls)
 364                 return NULL;
 365         ls->dim = isl_dim_from_domain(ls->dim);
 366         if (!ls->dim)
 367                 return isl_local_space_free(ls);
 368         return ls;
 369 }
 370
 371 __isl_give isl_local_space *isl_local_space_add_dim(
 372         __isl_take isl_local_space *ls, enum isl_dim_type type, unsigned n)
 373 {
 374         int pos;
 375
 376         if (n == 0)
 377                 return ls;
 378
 379         ls = isl_local_space_cow(ls);
 380         if (!ls)
 381                 return NULL;
 382
 383         pos = isl_local_space_offset(ls, type);
 384         pos += isl_local_space_dim(ls, type);
 385
 386         ls->div = isl_mat_insert_zero_cols(ls->div, 1 + pos, n);
 387
 388         if (type == isl_dim_div) {
 389                 ls->div = isl_mat_add_zero_rows(ls->div, n);
 390         } else {
 391                 ls->dim = isl_dim_add(ls->dim, type, n);
 392                 if (!ls->dim)
 393                         return isl_local_space_free(ls);
 394         }
 395
 396         if (!ls->div)
 397                 return isl_local_space_free(ls);
 398
 399         return ls;
 400 }
 401
 402 /* Remove common factor of non-constant terms and denominator.
 403  */
 404 static void normalize_div(__isl_keep isl_local_space *ls, int div)
 405 {
 406         isl_ctx *ctx = ls->div->ctx;
 407         unsigned total = ls->div->n_col - 2;
 408
 409         isl_seq_gcd(ls->div->row[div] + 2, total, &ctx->normalize_gcd);
 410         isl_int_gcd(ctx->normalize_gcd,
 411                     ctx->normalize_gcd, ls->div->row[div][0]);
 412         if (isl_int_is_one(ctx->normalize_gcd))
 413                 return;
 414
 415         isl_seq_scale_down(ls->div->row[div] + 2, ls->div->row[div] + 2,
 416                             ctx->normalize_gcd, total);
 417         isl_int_divexact(ls->div->row[div][0], ls->div->row[div][0],
 418                             ctx->normalize_gcd);
 419         isl_int_fdiv_q(ls->div->row[div][1], ls->div->row[div][1],
 420                             ctx->normalize_gcd);
 421 }
 422
 423 /* Exploit the equalities in "eq" to simplify the expressions of
 424  * the integer divisions in "ls".
 425  * The integer divisions in "ls" are assumed to appear as regular
 426  * dimensions in "eq".
 427  */
 428 __isl_give isl_local_space *isl_local_space_substitute_equalities(
 429         __isl_take isl_local_space *ls, __isl_take isl_basic_set *eq)
 430 {
 431         int i, j, k;
 432         unsigned total;
 433         unsigned n_div;
 434
 435         ls = isl_local_space_cow(ls);
 436         if (!ls || !eq)
 437                 goto error;
 438
 439         total = isl_dim_total(eq->dim);
 440         if (isl_local_space_dim(ls, isl_dim_all) != total)
 441                 isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
 442                         "dimensions don't match", goto error);
 443         total++;
 444         n_div = eq->n_div;
 445         for (i = 0; i < eq->n_eq; ++i) {
 446                 j = isl_seq_last_non_zero(eq->eq[i], total + n_div);
 447                 if (j < 0 || j == 0 || j >= total)
 448                         continue;
 449
 450                 for (k = 0; k < ls->div->n_row; ++k) {
 451                         if (isl_int_is_zero(ls->div->row[k][1 + j]))
 452                                 continue;
 453                         isl_seq_elim(ls->div->row[k] + 1, eq->eq[i], j, total,
 454                                         &ls->div->row[k][0]);
 455                         normalize_div(ls, k);
 456                 }
 457         }
 458
 459         isl_basic_set_free(eq);
 460         return ls;
 461 error:
 462         isl_basic_set_free(eq);
 463         isl_local_space_free(ls);
 464         return NULL;
 465 }