1 /* Supporting functions for resolving DATA statement.
2 Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007
3 Free Software Foundation, Inc.
4 Contributed by Lifang Zeng <zlf605@hotmail.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor,Boston, MA
24 /* Notes for DATA statement implementation:
26 We first assign initial value to each symbol by gfc_assign_data_value
27 during resolveing DATA statement. Refer to check_data_variable and
28 traverse_data_list in resolve.c.
30 The complexity exists in the handling of array section, implied do
31 and array of struct appeared in DATA statement.
33 We call gfc_conv_structure, gfc_con_array_array_initializer,
34 etc., to convert the initial value. Refer to trans-expr.c and
40 static void formalize_init_expr (gfc_expr *);
42 /* Calculate the array element offset. */
45 get_array_index (gfc_array_ref *ar, mpz_t *offset)
54 mpz_set_si (*offset, 0);
55 mpz_init_set_si (delta, 1);
56 for (i = 0; i < ar->dimen; i++)
58 e = gfc_copy_expr (ar->start[i]);
59 re = gfc_simplify_expr (e, 1);
61 if ((gfc_is_constant_expr (ar->as->lower[i]) == 0)
62 || (gfc_is_constant_expr (ar->as->upper[i]) == 0)
63 || (gfc_is_constant_expr (e) == 0))
64 gfc_error ("non-constant array in DATA statement %L", &ar->where);
66 mpz_set (tmp, e->value.integer);
67 mpz_sub (tmp, tmp, ar->as->lower[i]->value.integer);
68 mpz_mul (tmp, tmp, delta);
69 mpz_add (*offset, tmp, *offset);
71 mpz_sub (tmp, ar->as->upper[i]->value.integer,
72 ar->as->lower[i]->value.integer);
73 mpz_add_ui (tmp, tmp, 1);
74 mpz_mul (delta, tmp, delta);
81 /* Find if there is a constructor which offset is equal to OFFSET. */
83 static gfc_constructor *
84 find_con_by_offset (splay_tree spt, mpz_t offset)
87 gfc_constructor *ret = NULL;
91 /* The complexity is due to needing quick access to the linked list of
92 constructors. Both a linked list and a splay tree are used, and both
93 are kept up to date if they are array elements (which is the only time
94 that a specific constructor has to be found). */
96 gcc_assert (spt != NULL);
99 sptn = splay_tree_lookup (spt, (splay_tree_key) mpz_get_si (offset));
102 ret = (gfc_constructor*) sptn->value;
105 /* Need to check and see if we match a range, so we will pull
106 the next lowest index and see if the range matches. */
107 sptn = splay_tree_predecessor (spt,
108 (splay_tree_key) mpz_get_si (offset));
111 con = (gfc_constructor*) sptn->value;
112 if (mpz_cmp_ui (con->repeat, 1) > 0)
115 mpz_add (tmp, con->n.offset, con->repeat);
116 if (mpz_cmp (offset, tmp) < 0)
121 ret = NULL; /* The range did not match. */
124 ret = NULL; /* No pred, so no match. */
131 /* Find if there is a constructor which component is equal to COM. */
133 static gfc_constructor *
134 find_con_by_component (gfc_component *com, gfc_constructor *con)
136 for (; con; con = con->next)
138 if (com == con->n.component)
145 /* Create a character type initialization expression from RVALUE.
146 TS [and REF] describe [the substring of] the variable being initialized.
147 INIT is thh existing initializer, not NULL. Initialization is performed
148 according to normal assignment rules. */
151 create_character_intializer (gfc_expr *init, gfc_typespec *ts,
152 gfc_ref *ref, gfc_expr *rvalue)
159 gfc_extract_int (ts->cl->length, &len);
163 /* Create a new initializer. */
164 init = gfc_get_expr ();
165 init->expr_type = EXPR_CONSTANT;
168 dest = gfc_getmem (len + 1);
170 init->value.character.length = len;
171 init->value.character.string = dest;
172 /* Blank the string if we're only setting a substring. */
174 memset (dest, ' ', len);
177 dest = init->value.character.string;
181 gfc_expr *start_expr, *end_expr;
183 gcc_assert (ref->type == REF_SUBSTRING);
185 /* Only set a substring of the destination. Fortran substring bounds
186 are one-based [start, end], we want zero based [start, end). */
187 start_expr = gfc_copy_expr (ref->u.ss.start);
188 end_expr = gfc_copy_expr (ref->u.ss.end);
190 if ((gfc_simplify_expr (start_expr, 1) == FAILURE)
191 || (gfc_simplify_expr (end_expr, 1)) == FAILURE)
193 gfc_error ("failure to simplify substring reference in DATA "
194 "statement at %L", &ref->u.ss.start->where);
198 gfc_extract_int (start_expr, &start);
200 gfc_extract_int (end_expr, &end);
204 /* Set the whole string. */
209 /* Copy the initial value. */
210 len = rvalue->value.character.length;
211 if (len > end - start)
214 gfc_warning_now ("initialization string truncated to match variable "
215 "at %L", &rvalue->where);
218 memcpy (&dest[start], rvalue->value.character.string, len);
220 /* Pad with spaces. Substrings will already be blanked. */
221 if (len < end - start && ref == NULL)
222 memset (&dest[start + len], ' ', end - (start + len));
224 if (rvalue->ts.type == BT_HOLLERITH)
231 /* Assign the initial value RVALUE to LVALUE's symbol->value. If the
232 LVALUE already has an initialization, we extend this, otherwise we
236 gfc_assign_data_value (gfc_expr *lvalue, gfc_expr *rvalue, mpz_t index)
241 gfc_constructor *con;
242 gfc_constructor *last_con;
243 gfc_constructor *pred;
245 gfc_typespec *last_ts;
248 splay_tree_node sptn;
250 symbol = lvalue->symtree->n.sym;
251 init = symbol->value;
252 last_ts = &symbol->ts;
254 mpz_init_set_si (offset, 0);
256 /* Find/create the parent expressions for subobject references. */
257 for (ref = lvalue->ref; ref; ref = ref->next)
259 /* Break out of the loop if we find a substring. */
260 if (ref->type == REF_SUBSTRING)
262 /* A substring should always be the last subobject reference. */
263 gcc_assert (ref->next == NULL);
267 /* Use the existing initializer expression if it exists. Otherwise
270 expr = gfc_get_expr ();
274 /* Find or create this element. */
280 /* The element typespec will be the same as the array
283 /* Setup the expression to hold the constructor. */
284 expr->expr_type = EXPR_ARRAY;
285 expr->rank = ref->u.ar.as->rank;
288 gcc_assert (expr->expr_type == EXPR_ARRAY);
290 if (ref->u.ar.type == AR_ELEMENT)
291 get_array_index (&ref->u.ar, &offset);
293 mpz_set (offset, index);
295 /* Splay tree containing offset and gfc_constructor. */
296 spt = expr->con_by_offset;
300 spt = splay_tree_new (splay_tree_compare_ints, NULL, NULL);
301 expr->con_by_offset = spt;
305 con = find_con_by_offset (spt, offset);
311 /* Create a new constructor. */
312 con = gfc_get_constructor ();
313 mpz_set (con->n.offset, offset);
314 j = (splay_tree_key) mpz_get_si (offset);
315 sptn = splay_tree_insert (spt, j, (splay_tree_value) con);
316 /* Fix up the linked list. */
317 sptn = splay_tree_predecessor (spt, j);
319 { /* Insert at the head. */
320 con->next = expr->value.constructor;
321 expr->value.constructor = con;
324 { /* Insert in the chain. */
325 pred = (gfc_constructor*) sptn->value;
326 con->next = pred->next;
335 /* Setup the expression to hold the constructor. */
336 expr->expr_type = EXPR_STRUCTURE;
337 expr->ts.type = BT_DERIVED;
338 expr->ts.derived = ref->u.c.sym;
341 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
342 last_ts = &ref->u.c.component->ts;
344 /* Find the same element in the existing constructor. */
345 con = expr->value.constructor;
346 con = find_con_by_component (ref->u.c.component, con);
350 /* Create a new constructor. */
351 con = gfc_get_constructor ();
352 con->n.component = ref->u.c.component;
353 con->next = expr->value.constructor;
354 expr->value.constructor = con;
364 /* Point the container at the new expression. */
365 if (last_con == NULL)
366 symbol->value = expr;
368 last_con->expr = expr;
374 if (ref || last_ts->type == BT_CHARACTER)
375 expr = create_character_intializer (init, last_ts, ref, rvalue);
378 /* Overwriting an existing initializer is non-standard but usually only
379 provokes a warning from other compilers. */
382 /* Order in which the expressions arrive here depends on whether
383 they are from data statements or F95 style declarations.
384 Therefore, check which is the most recent. */
385 #ifdef USE_MAPPED_LOCATION
386 expr = (LOCATION_LINE (init->where.lb->location)
387 > LOCATION_LINE (rvalue->where.lb->location))
390 expr = (init->where.lb->linenum > rvalue->where.lb->linenum)
393 gfc_notify_std (GFC_STD_GNU, "Extension: re-initialization "
394 "of '%s' at %L", symbol->name, &expr->where);
397 expr = gfc_copy_expr (rvalue);
398 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
399 gfc_convert_type (expr, &lvalue->ts, 0);
402 if (last_con == NULL)
403 symbol->value = expr;
405 last_con->expr = expr;
409 /* Similarly, but initialize REPEAT consecutive values in LVALUE the same
410 value in RVALUE. For the nonce, LVALUE must refer to a full array, not
414 gfc_assign_data_value_range (gfc_expr *lvalue, gfc_expr *rvalue,
415 mpz_t index, mpz_t repeat)
418 gfc_expr *init, *expr;
419 gfc_constructor *con, *last_con;
420 gfc_constructor *pred;
422 gfc_typespec *last_ts;
425 splay_tree_node sptn;
427 symbol = lvalue->symtree->n.sym;
428 init = symbol->value;
429 last_ts = &symbol->ts;
431 mpz_init_set_si (offset, 0);
433 /* Find/create the parent expressions for subobject references. */
434 for (ref = lvalue->ref; ref; ref = ref->next)
436 /* Use the existing initializer expression if it exists.
437 Otherwise create a new one. */
439 expr = gfc_get_expr ();
443 /* Find or create this element. */
449 /* The element typespec will be the same as the array
452 /* Setup the expression to hold the constructor. */
453 expr->expr_type = EXPR_ARRAY;
454 expr->rank = ref->u.ar.as->rank;
457 gcc_assert (expr->expr_type == EXPR_ARRAY);
459 if (ref->u.ar.type == AR_ELEMENT)
461 get_array_index (&ref->u.ar, &offset);
463 /* This had better not be the bottom of the reference.
464 We can still get to a full array via a component. */
465 gcc_assert (ref->next != NULL);
469 mpz_set (offset, index);
471 /* We're at a full array or an array section. This means
472 that we've better have found a full array, and that we're
473 at the bottom of the reference. */
474 gcc_assert (ref->u.ar.type == AR_FULL);
475 gcc_assert (ref->next == NULL);
478 /* Find the same element in the existing constructor. */
480 /* Splay tree containing offset and gfc_constructor. */
481 spt = expr->con_by_offset;
485 spt = splay_tree_new (splay_tree_compare_ints, NULL, NULL);
486 expr->con_by_offset = spt;
490 con = find_con_by_offset (spt, offset);
495 /* Create a new constructor. */
496 con = gfc_get_constructor ();
497 mpz_set (con->n.offset, offset);
498 j = (splay_tree_key) mpz_get_si (offset);
500 if (ref->next == NULL)
501 mpz_set (con->repeat, repeat);
502 sptn = splay_tree_insert (spt, j, (splay_tree_value) con);
503 /* Fix up the linked list. */
504 sptn = splay_tree_predecessor (spt, j);
506 { /* Insert at the head. */
507 con->next = expr->value.constructor;
508 expr->value.constructor = con;
511 { /* Insert in the chain. */
512 pred = (gfc_constructor*) sptn->value;
513 con->next = pred->next;
518 gcc_assert (ref->next != NULL);
524 /* Setup the expression to hold the constructor. */
525 expr->expr_type = EXPR_STRUCTURE;
526 expr->ts.type = BT_DERIVED;
527 expr->ts.derived = ref->u.c.sym;
530 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
531 last_ts = &ref->u.c.component->ts;
533 /* Find the same element in the existing constructor. */
534 con = expr->value.constructor;
535 con = find_con_by_component (ref->u.c.component, con);
539 /* Create a new constructor. */
540 con = gfc_get_constructor ();
541 con->n.component = ref->u.c.component;
542 con->next = expr->value.constructor;
543 expr->value.constructor = con;
546 /* Since we're only intending to initialize arrays here,
547 there better be an inner reference. */
548 gcc_assert (ref->next != NULL);
558 /* Point the container at the new expression. */
559 if (last_con == NULL)
560 symbol->value = expr;
562 last_con->expr = expr;
568 if (last_ts->type == BT_CHARACTER)
569 expr = create_character_intializer (init, last_ts, NULL, rvalue);
572 /* We should never be overwriting an existing initializer. */
575 expr = gfc_copy_expr (rvalue);
576 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
577 gfc_convert_type (expr, &lvalue->ts, 0);
580 if (last_con == NULL)
581 symbol->value = expr;
583 last_con->expr = expr;
586 /* Modify the index of array section and re-calculate the array offset. */
589 gfc_advance_section (mpz_t *section_index, gfc_array_ref *ar,
598 for (i = 0; i < ar->dimen; i++)
600 if (ar->dimen_type[i] != DIMEN_RANGE)
605 mpz_add (section_index[i], section_index[i],
606 ar->stride[i]->value.integer);
607 if (mpz_cmp_si (ar->stride[i]->value.integer, 0) >= 0)
614 mpz_add_ui (section_index[i], section_index[i], 1);
619 cmp = mpz_cmp (section_index[i], ar->end[i]->value.integer);
621 cmp = mpz_cmp (section_index[i], ar->as->upper[i]->value.integer);
623 if ((cmp > 0 && forwards) || (cmp < 0 && !forwards))
625 /* Reset index to start, then loop to advance the next index. */
627 mpz_set (section_index[i], ar->start[i]->value.integer);
629 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
635 mpz_set_si (*offset_ret, 0);
636 mpz_init_set_si (delta, 1);
638 for (i = 0; i < ar->dimen; i++)
640 mpz_sub (tmp, section_index[i], ar->as->lower[i]->value.integer);
641 mpz_mul (tmp, tmp, delta);
642 mpz_add (*offset_ret, tmp, *offset_ret);
644 mpz_sub (tmp, ar->as->upper[i]->value.integer,
645 ar->as->lower[i]->value.integer);
646 mpz_add_ui (tmp, tmp, 1);
647 mpz_mul (delta, tmp, delta);
654 /* Rearrange a structure constructor so the elements are in the specified
655 order. Also insert NULL entries if necessary. */
658 formalize_structure_cons (gfc_expr *expr)
660 gfc_constructor *head;
661 gfc_constructor *tail;
662 gfc_constructor *cur;
663 gfc_constructor *last;
665 gfc_component *order;
667 c = expr->value.constructor;
669 /* Constructor is already formalized. */
670 if (c->n.component == NULL)
674 for (order = expr->ts.derived->components; order; order = order->next)
676 /* Find the next component. */
679 while (cur != NULL && cur->n.component != order)
687 /* Create a new one. */
688 cur = gfc_get_constructor ();
692 /* Remove it from the chain. */
696 last->next = cur->next;
699 formalize_init_expr (cur->expr);
702 /* Add it to the new constructor. */
711 gcc_assert (c == NULL);
712 expr->value.constructor = head;
716 /* Make sure an initialization expression is in normalized form. Ie. all
717 elements of the constructors are in the correct order. */
720 formalize_init_expr (gfc_expr *expr)
728 type = expr->expr_type;
732 c = expr->value.constructor;
735 formalize_init_expr (c->expr);
741 formalize_structure_cons (expr);
750 /* Resolve symbol's initial value after all data statement. */
753 gfc_formalize_init_value (gfc_symbol *sym)
755 formalize_init_expr (sym->value);
759 /* Get the integer value into RET_AS and SECTION from AS and AR, and return
763 gfc_get_section_index (gfc_array_ref *ar, mpz_t *section_index, mpz_t *offset)
769 mpz_set_si (*offset, 0);
771 mpz_init_set_si (delta, 1);
772 for (i = 0; i < ar->dimen; i++)
774 mpz_init (section_index[i]);
775 switch (ar->dimen_type[i])
781 mpz_sub (tmp, ar->start[i]->value.integer,
782 ar->as->lower[i]->value.integer);
783 mpz_mul (tmp, tmp, delta);
784 mpz_add (*offset, tmp, *offset);
785 mpz_set (section_index[i], ar->start[i]->value.integer);
788 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
792 gfc_internal_error ("TODO: Vector sections in data statements");
798 mpz_sub (tmp, ar->as->upper[i]->value.integer,
799 ar->as->lower[i]->value.integer);
800 mpz_add_ui (tmp, tmp, 1);
801 mpz_mul (delta, tmp, delta);