gcc/fortran/data.c

   1 /* Supporting functions for resolving DATA statement.
   2    Copyright (C) 2002-2017 Free Software Foundation, Inc.
   3    Contributed by Lifang Zeng <zlf605@hotmail.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21
  22 /* Notes for DATA statement implementation:
  23
  24    We first assign initial value to each symbol by gfc_assign_data_value
  25    during resolving DATA statement. Refer to check_data_variable and
  26    traverse_data_list in resolve.c.
  27
  28    The complexity exists in the handling of array section, implied do
  29    and array of struct appeared in DATA statement.
  30
  31    We call gfc_conv_structure, gfc_con_array_array_initializer,
  32    etc., to convert the initial value. Refer to trans-expr.c and
  33    trans-array.c.  */
  34
  35 #include "config.h"
  36 #include "system.h"
  37 #include "coretypes.h"
  38 #include "gfortran.h"
  39 #include "data.h"
  40 #include "constructor.h"
  41
  42 static void formalize_init_expr (gfc_expr *);
  43
  44 /* Calculate the array element offset.  */
  45
  46 static void
  47 get_array_index (gfc_array_ref *ar, mpz_t *offset)
  48 {
  49   gfc_expr *e;
  50   int i;
  51   mpz_t delta;
  52   mpz_t tmp;
  53
  54   mpz_init (tmp);
  55   mpz_set_si (*offset, 0);
  56   mpz_init_set_si (delta, 1);
  57   for (i = 0; i < ar->dimen; i++)
  58     {
  59       e = gfc_copy_expr (ar->start[i]);
  60       gfc_simplify_expr (e, 1);
  61
  62       if ((gfc_is_constant_expr (ar->as->lower[i]) == 0)
  63           || (gfc_is_constant_expr (ar->as->upper[i]) == 0)
  64           || (gfc_is_constant_expr (e) == 0))
  65         gfc_error ("non-constant array in DATA statement %L", &ar->where);
  66
  67       mpz_set (tmp, e->value.integer);
  68       gfc_free_expr (e);
  69       mpz_sub (tmp, tmp, ar->as->lower[i]->value.integer);
  70       mpz_mul (tmp, tmp, delta);
  71       mpz_add (*offset, tmp, *offset);
  72
  73       mpz_sub (tmp, ar->as->upper[i]->value.integer,
  74                ar->as->lower[i]->value.integer);
  75       mpz_add_ui (tmp, tmp, 1);
  76       mpz_mul (delta, tmp, delta);
  77     }
  78   mpz_clear (delta);
  79   mpz_clear (tmp);
  80 }
  81
  82 /* Find if there is a constructor which component is equal to COM.
  83    TODO: remove this, use symbol.c(gfc_find_component) instead.  */
  84
  85 static gfc_constructor *
  86 find_con_by_component (gfc_component *com, gfc_constructor_base base)
  87 {
  88   gfc_constructor *c;
  89
  90   for (c = gfc_constructor_first (base); c; c = gfc_constructor_next (c))
  91     if (com == c->n.component)
  92       return c;
  93
  94   return NULL;
  95 }
  96
  97
  98 /* Create a character type initialization expression from RVALUE.
  99    TS [and REF] describe [the substring of] the variable being initialized.
 100    INIT is the existing initializer, not NULL.  Initialization is performed
 101    according to normal assignment rules.  */
 102
 103 static gfc_expr *
 104 create_character_initializer (gfc_expr *init, gfc_typespec *ts,
 105                               gfc_ref *ref, gfc_expr *rvalue)
 106 {
 107   int len, start, end, tlen;
 108   gfc_char_t *dest;
 109   bool alloced_init = false;
 110
 111   gfc_extract_int (ts->u.cl->length, &len);
 112
 113   if (init == NULL)
 114     {
 115       /* Create a new initializer.  */
 116       init = gfc_get_character_expr (ts->kind, NULL, NULL, len);
 117       init->ts = *ts;
 118       alloced_init = true;
 119     }
 120
 121   dest = init->value.character.string;
 122
 123   if (ref)
 124     {
 125       gfc_expr *start_expr, *end_expr;
 126
 127       gcc_assert (ref->type == REF_SUBSTRING);
 128
 129       /* Only set a substring of the destination.  Fortran substring bounds
 130          are one-based [start, end], we want zero based [start, end).  */
 131       start_expr = gfc_copy_expr (ref->u.ss.start);
 132       end_expr = gfc_copy_expr (ref->u.ss.end);
 133
 134       if ((!gfc_simplify_expr(start_expr, 1))
 135           || !(gfc_simplify_expr(end_expr, 1)))
 136         {
 137           gfc_error ("failure to simplify substring reference in DATA "
 138                      "statement at %L", &ref->u.ss.start->where);
 139           gfc_free_expr (start_expr);
 140           gfc_free_expr (end_expr);
 141           if (alloced_init)
 142             gfc_free_expr (init);
 143           return NULL;
 144         }
 145
 146       gfc_extract_int (start_expr, &start);
 147       gfc_free_expr (start_expr);
 148       start--;
 149       gfc_extract_int (end_expr, &end);
 150       gfc_free_expr (end_expr);
 151     }
 152   else
 153     {
 154       /* Set the whole string.  */
 155       start = 0;
 156       end = len;
 157     }
 158
 159   /* Copy the initial value.  */
 160   if (rvalue->ts.type == BT_HOLLERITH)
 161     len = rvalue->representation.length - rvalue->ts.u.pad;
 162   else
 163     len = rvalue->value.character.length;
 164
 165   tlen = end - start;
 166   if (len > tlen)
 167     {
 168       if (tlen < 0)
 169         {
 170           gfc_warning_now (0, "Unused initialization string at %L because "
 171                            "variable has zero length", &rvalue->where);
 172           len = 0;
 173         }
 174       else
 175         {
 176           gfc_warning_now (0, "Initialization string at %L was truncated to "
 177                            "fit the variable (%d/%d)", &rvalue->where,
 178                            tlen, len);
 179           len = tlen;
 180         }
 181     }
 182
 183   if (rvalue->ts.type == BT_HOLLERITH)
 184     {
 185       int i;
 186       for (i = 0; i < len; i++)
 187         dest[start+i] = rvalue->representation.string[i];
 188     }
 189   else
 190     memcpy (&dest[start], rvalue->value.character.string,
 191             len * sizeof (gfc_char_t));
 192
 193   /* Pad with spaces.  Substrings will already be blanked.  */
 194   if (len < tlen && ref == NULL)
 195     gfc_wide_memset (&dest[start + len], ' ', end - (start + len));
 196
 197   if (rvalue->ts.type == BT_HOLLERITH)
 198     {
 199       init->representation.length = init->value.character.length;
 200       init->representation.string
 201         = gfc_widechar_to_char (init->value.character.string,
 202                                 init->value.character.length);
 203     }
 204
 205   return init;
 206 }
 207
 208
 209 /* Assign the initial value RVALUE to  LVALUE's symbol->value. If the
 210    LVALUE already has an initialization, we extend this, otherwise we
 211    create a new one.  If REPEAT is non-NULL, initialize *REPEAT
 212    consecutive values in LVALUE the same value in RVALUE.  In that case,
 213    LVALUE must refer to a full array, not an array section.  */
 214
 215 bool
 216 gfc_assign_data_value (gfc_expr *lvalue, gfc_expr *rvalue, mpz_t index,
 217                        mpz_t *repeat)
 218 {
 219   gfc_ref *ref;
 220   gfc_expr *init;
 221   gfc_expr *expr = NULL;
 222   gfc_constructor *con;
 223   gfc_constructor *last_con;
 224   gfc_symbol *symbol;
 225   gfc_typespec *last_ts;
 226   mpz_t offset;
 227
 228   symbol = lvalue->symtree->n.sym;
 229   init = symbol->value;
 230   last_ts = &symbol->ts;
 231   last_con = NULL;
 232   mpz_init_set_si (offset, 0);
 233
 234   /* Find/create the parent expressions for subobject references.  */
 235   for (ref = lvalue->ref; ref; ref = ref->next)
 236     {
 237       /* Break out of the loop if we find a substring.  */
 238       if (ref->type == REF_SUBSTRING)
 239         {
 240           /* A substring should always be the last subobject reference.  */
 241           gcc_assert (ref->next == NULL);
 242           break;
 243         }
 244
 245       /* Use the existing initializer expression if it exists.  Otherwise
 246          create a new one.  */
 247       if (init == NULL)
 248         expr = gfc_get_expr ();
 249       else
 250         expr = init;
 251
 252       /* Find or create this element.  */
 253       switch (ref->type)
 254         {
 255         case REF_ARRAY:
 256           if (ref->u.ar.as->rank == 0)
 257             {
 258               gcc_assert (ref->u.ar.as->corank > 0);
 259               if (init == NULL)
 260                 free (expr);
 261               continue;
 262             }
 263
 264           if (init && expr->expr_type != EXPR_ARRAY)
 265             {
 266               gfc_error ("%qs at %L already is initialized at %L",
 267                          lvalue->symtree->n.sym->name, &lvalue->where,
 268                          &init->where);
 269               goto abort;
 270             }
 271
 272           if (init == NULL)
 273             {
 274               /* The element typespec will be the same as the array
 275                  typespec.  */
 276               expr->ts = *last_ts;
 277               /* Setup the expression to hold the constructor.  */
 278               expr->expr_type = EXPR_ARRAY;
 279               expr->rank = ref->u.ar.as->rank;
 280             }
 281
 282           if (ref->u.ar.type == AR_ELEMENT)
 283             get_array_index (&ref->u.ar, &offset);
 284           else
 285             mpz_set (offset, index);
 286
 287           /* Check the bounds.  */
 288           if (mpz_cmp_si (offset, 0) < 0)
 289             {
 290               gfc_error ("Data element below array lower bound at %L",
 291                          &lvalue->where);
 292               goto abort;
 293             }
 294           else if (repeat != NULL
 295                    && ref->u.ar.type != AR_ELEMENT)
 296             {
 297               mpz_t size, end;
 298               gcc_assert (ref->u.ar.type == AR_FULL
 299                           && ref->next == NULL);
 300               mpz_init_set (end, offset);
 301               mpz_add (end, end, *repeat);
 302               if (spec_size (ref->u.ar.as, &size))
 303                 {
 304                   if (mpz_cmp (end, size) > 0)
 305                     {
 306                       mpz_clear (size);
 307                       gfc_error ("Data element above array upper bound at %L",
 308                                  &lvalue->where);
 309                       goto abort;
 310                     }
 311                   mpz_clear (size);
 312                 }
 313
 314               con = gfc_constructor_lookup (expr->value.constructor,
 315                                             mpz_get_si (offset));
 316               if (!con)
 317                 {
 318                   con = gfc_constructor_lookup_next (expr->value.constructor,
 319                                                      mpz_get_si (offset));
 320                   if (con != NULL && mpz_cmp (con->offset, end) >= 0)
 321                     con = NULL;
 322                 }
 323
 324               /* Overwriting an existing initializer is non-standard but
 325                  usually only provokes a warning from other compilers.  */
 326               if (con != NULL && con->expr != NULL)
 327                 {
 328                   /* Order in which the expressions arrive here depends on
 329                      whether they are from data statements or F95 style
 330                      declarations.  Therefore, check which is the most
 331                      recent.  */
 332                   gfc_expr *exprd;
 333                   exprd = (LOCATION_LINE (con->expr->where.lb->location)
 334                            > LOCATION_LINE (rvalue->where.lb->location))
 335                           ? con->expr : rvalue;
 336                   if (gfc_notify_std (GFC_STD_GNU,
 337                                       "re-initialization of %qs at %L",
 338                                       symbol->name, &exprd->where) == false)
 339                     return false;
 340                 }
 341
 342               while (con != NULL)
 343                 {
 344                   gfc_constructor *next_con = gfc_constructor_next (con);
 345
 346                   if (mpz_cmp (con->offset, end) >= 0)
 347                     break;
 348                   if (mpz_cmp (con->offset, offset) < 0)
 349                     {
 350                       gcc_assert (mpz_cmp_si (con->repeat, 1) > 0);
 351                       mpz_sub (con->repeat, offset, con->offset);
 352                     }
 353                   else if (mpz_cmp_si (con->repeat, 1) > 0
 354                            && mpz_get_si (con->offset)
 355                               + mpz_get_si (con->repeat) > mpz_get_si (end))
 356                     {
 357                       int endi;
 358                       splay_tree_node node
 359                         = splay_tree_lookup (con->base,
 360                                              mpz_get_si (con->offset));
 361                       gcc_assert (node
 362                                   && con == (gfc_constructor *) node->value
 363                                   && node->key == (splay_tree_key)
 364                                                   mpz_get_si (con->offset));
 365                       endi = mpz_get_si (con->offset)
 366                              + mpz_get_si (con->repeat);
 367                       if (endi > mpz_get_si (end) + 1)
 368                         mpz_set_si (con->repeat, endi - mpz_get_si (end));
 369                       else
 370                         mpz_set_si (con->repeat, 1);
 371                       mpz_set (con->offset, end);
 372                       node->key = (splay_tree_key) mpz_get_si (end);
 373                       break;
 374                     }
 375                   else
 376                     gfc_constructor_remove (con);
 377                   con = next_con;
 378                 }
 379
 380               con = gfc_constructor_insert_expr (&expr->value.constructor,
 381                                                  NULL, &rvalue->where,
 382                                                  mpz_get_si (offset));
 383               mpz_set (con->repeat, *repeat);
 384               repeat = NULL;
 385               mpz_clear (end);
 386               break;
 387             }
 388           else
 389             {
 390               mpz_t size;
 391               if (spec_size (ref->u.ar.as, &size))
 392                 {
 393                   if (mpz_cmp (offset, size) >= 0)
 394                     {
 395                       mpz_clear (size);
 396                       gfc_error ("Data element above array upper bound at %L",
 397                                  &lvalue->where);
 398                       goto abort;
 399                     }
 400                   mpz_clear (size);
 401                 }
 402             }
 403
 404           con = gfc_constructor_lookup (expr->value.constructor,
 405                                         mpz_get_si (offset));
 406           if (!con)
 407             {
 408               con = gfc_constructor_insert_expr (&expr->value.constructor,
 409                                                  NULL, &rvalue->where,
 410                                                  mpz_get_si (offset));
 411             }
 412           else if (mpz_cmp_si (con->repeat, 1) > 0)
 413             {
 414               /* Need to split a range.  */
 415               if (mpz_cmp (con->offset, offset) < 0)
 416                 {
 417                   gfc_constructor *pred_con = con;
 418                   con = gfc_constructor_insert_expr (&expr->value.constructor,
 419                                                      NULL, &con->where,
 420                                                      mpz_get_si (offset));
 421                   con->expr = gfc_copy_expr (pred_con->expr);
 422                   mpz_add (con->repeat, pred_con->offset, pred_con->repeat);
 423                   mpz_sub (con->repeat, con->repeat, offset);
 424                   mpz_sub (pred_con->repeat, offset, pred_con->offset);
 425                 }
 426               if (mpz_cmp_si (con->repeat, 1) > 0)
 427                 {
 428                   gfc_constructor *succ_con;
 429                   succ_con
 430                     = gfc_constructor_insert_expr (&expr->value.constructor,
 431                                                    NULL, &con->where,
 432                                                    mpz_get_si (offset) + 1);
 433                   succ_con->expr = gfc_copy_expr (con->expr);
 434                   mpz_sub_ui (succ_con->repeat, con->repeat, 1);
 435                   mpz_set_si (con->repeat, 1);
 436                 }
 437             }
 438           break;
 439
 440         case REF_COMPONENT:
 441           if (init == NULL)
 442             {
 443               /* Setup the expression to hold the constructor.  */
 444               expr->expr_type = EXPR_STRUCTURE;
 445               expr->ts.type = BT_DERIVED;
 446               expr->ts.u.derived = ref->u.c.sym;
 447             }
 448           else
 449             gcc_assert (expr->expr_type == EXPR_STRUCTURE);
 450           last_ts = &ref->u.c.component->ts;
 451
 452           /* Find the same element in the existing constructor.  */
 453           con = find_con_by_component (ref->u.c.component,
 454                                        expr->value.constructor);
 455
 456           if (con == NULL)
 457             {
 458               /* Create a new constructor.  */
 459               con = gfc_constructor_append_expr (&expr->value.constructor,
 460                                                  NULL, NULL);
 461               con->n.component = ref->u.c.component;
 462             }
 463           break;
 464
 465         default:
 466           gcc_unreachable ();
 467         }
 468
 469       if (init == NULL)
 470         {
 471           /* Point the container at the new expression.  */
 472           if (last_con == NULL)
 473             symbol->value = expr;
 474           else
 475             last_con->expr = expr;
 476         }
 477       init = con->expr;
 478       last_con = con;
 479     }
 480
 481   mpz_clear (offset);
 482   gcc_assert (repeat == NULL);
 483
 484   if (ref || last_ts->type == BT_CHARACTER)
 485     {
 486       /* An initializer has to be constant.  */
 487       if (rvalue->expr_type != EXPR_CONSTANT
 488           || (lvalue->ts.u.cl->length == NULL
 489               && !(ref && ref->u.ss.length != NULL)))
 490         return false;
 491       expr = create_character_initializer (init, last_ts, ref, rvalue);
 492     }
 493   else
 494     {
 495       /* Overwriting an existing initializer is non-standard but usually only
 496          provokes a warning from other compilers.  */
 497       if (init != NULL)
 498         {
 499           /* Order in which the expressions arrive here depends on whether
 500              they are from data statements or F95 style declarations.
 501              Therefore, check which is the most recent.  */
 502           expr = (LOCATION_LINE (init->where.lb->location)
 503                   > LOCATION_LINE (rvalue->where.lb->location))
 504                ? init : rvalue;
 505           if (gfc_notify_std (GFC_STD_GNU,
 506                               "re-initialization of %qs at %L",
 507                               symbol->name, &expr->where) == false)
 508             return false;
 509         }
 510
 511       expr = gfc_copy_expr (rvalue);
 512       if (!gfc_compare_types (&lvalue->ts, &expr->ts))
 513         gfc_convert_type (expr, &lvalue->ts, 0);
 514     }
 515
 516   if (last_con == NULL)
 517     symbol->value = expr;
 518   else
 519     last_con->expr = expr;
 520
 521   return true;
 522
 523 abort:
 524   if (!init)
 525     gfc_free_expr (expr);
 526   mpz_clear (offset);
 527   return false;
 528 }
 529
 530
 531 /* Modify the index of array section and re-calculate the array offset.  */
 532
 533 void
 534 gfc_advance_section (mpz_t *section_index, gfc_array_ref *ar,
 535                      mpz_t *offset_ret)
 536 {
 537   int i;
 538   mpz_t delta;
 539   mpz_t tmp;
 540   bool forwards;
 541   int cmp;
 542   gfc_expr *start, *end, *stride;
 543
 544   for (i = 0; i < ar->dimen; i++)
 545     {
 546       if (ar->dimen_type[i] != DIMEN_RANGE)
 547         continue;
 548
 549       if (ar->stride[i])
 550         {
 551           stride = gfc_copy_expr(ar->stride[i]);
 552           if(!gfc_simplify_expr(stride, 1))
 553             gfc_internal_error("Simplification error");
 554           mpz_add (section_index[i], section_index[i],
 555                    stride->value.integer);
 556           if (mpz_cmp_si (stride->value.integer, 0) >= 0)
 557             forwards = true;
 558           else
 559             forwards = false;
 560           gfc_free_expr(stride);
 561         }
 562       else
 563         {
 564           mpz_add_ui (section_index[i], section_index[i], 1);
 565           forwards = true;
 566         }
 567
 568       if (ar->end[i])
 569         {
 570           end = gfc_copy_expr(ar->end[i]);
 571           if(!gfc_simplify_expr(end, 1))
 572             gfc_internal_error("Simplification error");
 573           cmp = mpz_cmp (section_index[i], end->value.integer);
 574           gfc_free_expr(end);
 575         }
 576       else
 577         cmp = mpz_cmp (section_index[i], ar->as->upper[i]->value.integer);
 578
 579       if ((cmp > 0 && forwards) || (cmp < 0 && !forwards))
 580         {
 581           /* Reset index to start, then loop to advance the next index.  */
 582           if (ar->start[i])
 583             {
 584               start = gfc_copy_expr(ar->start[i]);
 585               if(!gfc_simplify_expr(start, 1))
 586                 gfc_internal_error("Simplification error");
 587               mpz_set (section_index[i], start->value.integer);
 588               gfc_free_expr(start);
 589             }
 590           else
 591             mpz_set (section_index[i], ar->as->lower[i]->value.integer);
 592         }
 593       else
 594         break;
 595     }
 596
 597   mpz_set_si (*offset_ret, 0);
 598   mpz_init_set_si (delta, 1);
 599   mpz_init (tmp);
 600   for (i = 0; i < ar->dimen; i++)
 601     {
 602       mpz_sub (tmp, section_index[i], ar->as->lower[i]->value.integer);
 603       mpz_mul (tmp, tmp, delta);
 604       mpz_add (*offset_ret, tmp, *offset_ret);
 605
 606       mpz_sub (tmp, ar->as->upper[i]->value.integer,
 607                ar->as->lower[i]->value.integer);
 608       mpz_add_ui (tmp, tmp, 1);
 609       mpz_mul (delta, tmp, delta);
 610     }
 611   mpz_clear (tmp);
 612   mpz_clear (delta);
 613 }
 614
 615
 616 /* Rearrange a structure constructor so the elements are in the specified
 617    order.  Also insert NULL entries if necessary.  */
 618
 619 static void
 620 formalize_structure_cons (gfc_expr *expr)
 621 {
 622   gfc_constructor_base base = NULL;
 623   gfc_constructor *cur;
 624   gfc_component *order;
 625
 626   /* Constructor is already formalized.  */
 627   cur = gfc_constructor_first (expr->value.constructor);
 628   if (!cur || cur->n.component == NULL)
 629     return;
 630
 631   for (order = expr->ts.u.derived->components; order; order = order->next)
 632     {
 633       cur = find_con_by_component (order, expr->value.constructor);
 634       if (cur)
 635         gfc_constructor_append_expr (&base, cur->expr, &cur->expr->where);
 636       else
 637         gfc_constructor_append_expr (&base, NULL, NULL);
 638     }
 639
 640   /* For all what it's worth, one would expect
 641        gfc_constructor_free (expr->value.constructor);
 642      here. However, if the constructor is actually free'd,
 643      hell breaks loose in the testsuite?!  */
 644
 645   expr->value.constructor = base;
 646 }
 647
 648
 649 /* Make sure an initialization expression is in normalized form, i.e., all
 650    elements of the constructors are in the correct order.  */
 651
 652 static void
 653 formalize_init_expr (gfc_expr *expr)
 654 {
 655   expr_t type;
 656   gfc_constructor *c;
 657
 658   if (expr == NULL)
 659     return;
 660
 661   type = expr->expr_type;
 662   switch (type)
 663     {
 664     case EXPR_ARRAY:
 665       for (c = gfc_constructor_first (expr->value.constructor);
 666            c; c = gfc_constructor_next (c))
 667         formalize_init_expr (c->expr);
 668
 669     break;
 670
 671     case EXPR_STRUCTURE:
 672       formalize_structure_cons (expr);
 673       break;
 674
 675     default:
 676       break;
 677     }
 678 }
 679
 680
 681 /* Resolve symbol's initial value after all data statement.  */
 682
 683 void
 684 gfc_formalize_init_value (gfc_symbol *sym)
 685 {
 686   formalize_init_expr (sym->value);
 687 }
 688
 689
 690 /* Get the integer value into RET_AS and SECTION from AS and AR, and return
 691    offset.  */
 692
 693 void
 694 gfc_get_section_index (gfc_array_ref *ar, mpz_t *section_index, mpz_t *offset)
 695 {
 696   int i;
 697   mpz_t delta;
 698   mpz_t tmp;
 699   gfc_expr *start;
 700
 701   mpz_set_si (*offset, 0);
 702   mpz_init (tmp);
 703   mpz_init_set_si (delta, 1);
 704   for (i = 0; i < ar->dimen; i++)
 705     {
 706       mpz_init (section_index[i]);
 707       switch (ar->dimen_type[i])
 708         {
 709         case DIMEN_ELEMENT:
 710         case DIMEN_RANGE:
 711           if (ar->start[i])
 712             {
 713               start = gfc_copy_expr(ar->start[i]);
 714               if(!gfc_simplify_expr(start, 1))
 715                 gfc_internal_error("Simplification error");
 716               mpz_sub (tmp, start->value.integer,
 717                        ar->as->lower[i]->value.integer);
 718               mpz_mul (tmp, tmp, delta);
 719               mpz_add (*offset, tmp, *offset);
 720               mpz_set (section_index[i], start->value.integer);
 721               gfc_free_expr(start);
 722             }
 723           else
 724               mpz_set (section_index[i], ar->as->lower[i]->value.integer);
 725           break;
 726
 727         case DIMEN_VECTOR:
 728           gfc_internal_error ("TODO: Vector sections in data statements");
 729
 730         default:
 731           gcc_unreachable ();
 732         }
 733
 734       mpz_sub (tmp, ar->as->upper[i]->value.integer,
 735                ar->as->lower[i]->value.integer);
 736       mpz_add_ui (tmp, tmp, 1);
 737       mpz_mul (delta, tmp, delta);
 738     }
 739
 740   mpz_clear (tmp);
 741   mpz_clear (delta);
 742 }
 743