1 /* Supporting functions for resolving DATA statement.
2 Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software
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);
65 mpz_set (tmp, e->value.integer);
66 mpz_sub (tmp, tmp, ar->as->lower[i]->value.integer);
67 mpz_mul (tmp, tmp, delta);
68 mpz_add (*offset, tmp, *offset);
70 mpz_sub (tmp, ar->as->upper[i]->value.integer,
71 ar->as->lower[i]->value.integer);
72 mpz_add_ui (tmp, tmp, 1);
73 mpz_mul (delta, tmp, delta);
80 /* Find if there is a constructor which offset is equal to OFFSET. */
82 static gfc_constructor *
83 find_con_by_offset (splay_tree spt, mpz_t offset)
86 gfc_constructor *ret = NULL;
90 /* The complexity is due to needing quick access to the linked list of
91 constructors. Both a linked list and a splay tree are used, and both are
92 kept up to date if they are array elements (which is the only time that
93 a specific constructor has to be found). */
95 gcc_assert (spt != NULL);
98 sptn = splay_tree_lookup (spt, (splay_tree_key) mpz_get_si(offset));
101 ret = (gfc_constructor*) sptn->value;
104 /* Need to check and see if we match a range, so we will pull
105 the next lowest index and see if the range matches. */
106 sptn = splay_tree_predecessor (spt, (splay_tree_key) mpz_get_si(offset));
109 con = (gfc_constructor*) sptn->value;
110 if (mpz_cmp_ui (con->repeat, 1) > 0)
113 mpz_add (tmp, con->n.offset, con->repeat);
114 if (mpz_cmp (offset, tmp) < 0)
119 ret = NULL; /* The range did not match. */
122 ret = NULL; /* No pred, so no match. */
129 /* Find if there is a constructor which component is equal to COM. */
131 static gfc_constructor *
132 find_con_by_component (gfc_component *com, gfc_constructor *con)
134 for (; con; con = con->next)
136 if (com == con->n.component)
143 /* Create a character type initialization expression from RVALUE.
144 TS [and REF] describe [the substring of] the variable being initialized.
145 INIT is thh existing initializer, not NULL. Initialization is performed
146 according to normal assignment rules. */
149 create_character_intializer (gfc_expr * init, gfc_typespec * ts,
150 gfc_ref * ref, gfc_expr * rvalue)
157 gfc_extract_int (ts->cl->length, &len);
161 /* Create a new initializer. */
162 init = gfc_get_expr ();
163 init->expr_type = EXPR_CONSTANT;
166 dest = gfc_getmem (len + 1);
168 init->value.character.length = len;
169 init->value.character.string = dest;
170 /* Blank the string if we're only setting a substring. */
172 memset (dest, ' ', len);
175 dest = init->value.character.string;
179 gfc_expr *start_expr, *end_expr;
181 gcc_assert (ref->type == REF_SUBSTRING);
183 /* Only set a substring of the destination. Fortran substring bounds
184 are one-based [start, end], we want zero based [start, end). */
185 start_expr = gfc_copy_expr (ref->u.ss.start);
186 end_expr = gfc_copy_expr (ref->u.ss.end);
188 if ((gfc_simplify_expr (start_expr, 1) == FAILURE)
189 || (gfc_simplify_expr (end_expr, 1)) == FAILURE)
191 gfc_error ("failure to simplify substring reference in DATA"
192 "statement at %L", &ref->u.ss.start->where);
196 gfc_extract_int (start_expr, &start);
198 gfc_extract_int (end_expr, &end);
202 /* Set the whole string. */
207 /* Copy the initial value. */
208 len = rvalue->value.character.length;
209 if (len > end - start)
212 gfc_warning_now ("initialization string truncated to match variable "
213 "at %L", &rvalue->where);
216 memcpy (&dest[start], rvalue->value.character.string, len);
218 /* Pad with spaces. Substrings will already be blanked. */
219 if (len < end - start && ref == NULL)
220 memset (&dest[start + len], ' ', end - (start + len));
222 if (rvalue->ts.type == BT_HOLLERITH)
228 /* Assign the initial value RVALUE to LVALUE's symbol->value. If the
229 LVALUE already has an initialization, we extend this, otherwise we
233 gfc_assign_data_value (gfc_expr * lvalue, gfc_expr * rvalue, mpz_t index)
238 gfc_constructor *con;
239 gfc_constructor *last_con;
240 gfc_constructor *pred;
242 gfc_typespec *last_ts;
245 splay_tree_node sptn;
247 symbol = lvalue->symtree->n.sym;
248 init = symbol->value;
249 last_ts = &symbol->ts;
251 mpz_init_set_si (offset, 0);
253 /* Find/create the parent expressions for subobject references. */
254 for (ref = lvalue->ref; ref; ref = ref->next)
256 /* Break out of the loop if we find a substring. */
257 if (ref->type == REF_SUBSTRING)
259 /* A substring should always be the last subobject reference. */
260 gcc_assert (ref->next == NULL);
264 /* Use the existing initializer expression if it exists. Otherwise
267 expr = gfc_get_expr ();
271 /* Find or create this element. */
277 /* The element typespec will be the same as the array
280 /* Setup the expression to hold the constructor. */
281 expr->expr_type = EXPR_ARRAY;
282 expr->rank = ref->u.ar.as->rank;
285 gcc_assert (expr->expr_type == EXPR_ARRAY);
287 if (ref->u.ar.type == AR_ELEMENT)
288 get_array_index (&ref->u.ar, &offset);
290 mpz_set (offset, index);
292 /* Splay tree containing offset and gfc_constructor. */
293 spt = expr->con_by_offset;
297 spt = splay_tree_new (splay_tree_compare_ints,NULL,NULL);
298 expr->con_by_offset = spt;
302 con = find_con_by_offset (spt, offset);
306 /* Create a new constructor. */
307 con = gfc_get_constructor ();
308 mpz_set (con->n.offset, offset);
309 sptn = splay_tree_insert (spt, (splay_tree_key) mpz_get_si(offset),
310 (splay_tree_value) con);
311 /* Fix up the linked list. */
312 sptn = splay_tree_predecessor (spt, (splay_tree_key) mpz_get_si(offset));
314 { /* Insert at the head. */
315 con->next = expr->value.constructor;
316 expr->value.constructor = con;
319 { /* Insert in the chain. */
320 pred = (gfc_constructor*) sptn->value;
321 con->next = pred->next;
330 /* Setup the expression to hold the constructor. */
331 expr->expr_type = EXPR_STRUCTURE;
332 expr->ts.type = BT_DERIVED;
333 expr->ts.derived = ref->u.c.sym;
336 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
337 last_ts = &ref->u.c.component->ts;
339 /* Find the same element in the existing constructor. */
340 con = expr->value.constructor;
341 con = find_con_by_component (ref->u.c.component, con);
345 /* Create a new constructor. */
346 con = gfc_get_constructor ();
347 con->n.component = ref->u.c.component;
348 con->next = expr->value.constructor;
349 expr->value.constructor = con;
359 /* Point the container at the new expression. */
360 if (last_con == NULL)
361 symbol->value = expr;
363 last_con->expr = expr;
369 if (ref || last_ts->type == BT_CHARACTER)
370 expr = create_character_intializer (init, last_ts, ref, rvalue);
373 /* Overwriting an existing initializer is non-standard but usually only
374 provokes a warning from other compilers. */
377 /* Order in which the expressions arrive here depends on whether they
378 are from data statements or F95 style declarations. Therefore,
379 check which is the most recent. */
380 #ifdef USE_MAPPED_LOCATION
381 expr = (LOCATION_LINE (init->where.lb->location)
382 > LOCATION_LINE (rvalue->where.lb->location))
385 expr = (init->where.lb->linenum > rvalue->where.lb->linenum) ?
388 gfc_notify_std (GFC_STD_GNU, "Extension: re-initialization "
389 "of '%s' at %L", symbol->name, &expr->where);
392 expr = gfc_copy_expr (rvalue);
393 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
394 gfc_convert_type (expr, &lvalue->ts, 0);
397 if (last_con == NULL)
398 symbol->value = expr;
400 last_con->expr = expr;
403 /* Similarly, but initialize REPEAT consecutive values in LVALUE the same
404 value in RVALUE. For the nonce, LVALUE must refer to a full array, not
408 gfc_assign_data_value_range (gfc_expr * lvalue, gfc_expr * rvalue,
409 mpz_t index, mpz_t repeat)
412 gfc_expr *init, *expr;
413 gfc_constructor *con, *last_con;
414 gfc_constructor *pred;
416 gfc_typespec *last_ts;
419 splay_tree_node sptn;
421 symbol = lvalue->symtree->n.sym;
422 init = symbol->value;
423 last_ts = &symbol->ts;
425 mpz_init_set_si (offset, 0);
427 /* Find/create the parent expressions for subobject references. */
428 for (ref = lvalue->ref; ref; ref = ref->next)
430 /* Use the existing initializer expression if it exists.
431 Otherwise create a new one. */
433 expr = gfc_get_expr ();
437 /* Find or create this element. */
443 /* The element typespec will be the same as the array
446 /* Setup the expression to hold the constructor. */
447 expr->expr_type = EXPR_ARRAY;
448 expr->rank = ref->u.ar.as->rank;
451 gcc_assert (expr->expr_type == EXPR_ARRAY);
453 if (ref->u.ar.type == AR_ELEMENT)
455 get_array_index (&ref->u.ar, &offset);
457 /* This had better not be the bottom of the reference.
458 We can still get to a full array via a component. */
459 gcc_assert (ref->next != NULL);
463 mpz_set (offset, index);
465 /* We're at a full array or an array section. This means
466 that we've better have found a full array, and that we're
467 at the bottom of the reference. */
468 gcc_assert (ref->u.ar.type == AR_FULL);
469 gcc_assert (ref->next == NULL);
472 /* Find the same element in the existing constructor. */
474 /* Splay tree containing offset and gfc_constructor. */
475 spt = expr->con_by_offset;
479 spt = splay_tree_new (splay_tree_compare_ints,NULL,NULL);
480 expr->con_by_offset = spt;
484 con = find_con_by_offset (spt, offset);
488 /* Create a new constructor. */
489 con = gfc_get_constructor ();
490 mpz_set (con->n.offset, offset);
491 if (ref->next == NULL)
492 mpz_set (con->repeat, repeat);
493 sptn = splay_tree_insert (spt, (splay_tree_key) mpz_get_si(offset),
494 (splay_tree_value) con);
495 /* Fix up the linked list. */
496 sptn = splay_tree_predecessor (spt, (splay_tree_key) mpz_get_si(offset));
498 { /* Insert at the head. */
499 con->next = expr->value.constructor;
500 expr->value.constructor = con;
503 { /* Insert in the chain. */
504 pred = (gfc_constructor*) sptn->value;
505 con->next = pred->next;
510 gcc_assert (ref->next != NULL);
516 /* Setup the expression to hold the constructor. */
517 expr->expr_type = EXPR_STRUCTURE;
518 expr->ts.type = BT_DERIVED;
519 expr->ts.derived = ref->u.c.sym;
522 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
523 last_ts = &ref->u.c.component->ts;
525 /* Find the same element in the existing constructor. */
526 con = expr->value.constructor;
527 con = find_con_by_component (ref->u.c.component, con);
531 /* Create a new constructor. */
532 con = gfc_get_constructor ();
533 con->n.component = ref->u.c.component;
534 con->next = expr->value.constructor;
535 expr->value.constructor = con;
538 /* Since we're only intending to initialize arrays here,
539 there better be an inner reference. */
540 gcc_assert (ref->next != NULL);
550 /* Point the container at the new expression. */
551 if (last_con == NULL)
552 symbol->value = expr;
554 last_con->expr = expr;
560 if (last_ts->type == BT_CHARACTER)
561 expr = create_character_intializer (init, last_ts, NULL, rvalue);
564 /* We should never be overwriting an existing initializer. */
567 expr = gfc_copy_expr (rvalue);
568 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
569 gfc_convert_type (expr, &lvalue->ts, 0);
572 if (last_con == NULL)
573 symbol->value = expr;
575 last_con->expr = expr;
578 /* Modify the index of array section and re-calculate the array offset. */
581 gfc_advance_section (mpz_t *section_index, gfc_array_ref *ar,
590 for (i = 0; i < ar->dimen; i++)
592 if (ar->dimen_type[i] != DIMEN_RANGE)
597 mpz_add (section_index[i], section_index[i],
598 ar->stride[i]->value.integer);
599 if (mpz_cmp_si (ar->stride[i]->value.integer, 0) >= 0)
606 mpz_add_ui (section_index[i], section_index[i], 1);
611 cmp = mpz_cmp (section_index[i], ar->end[i]->value.integer);
613 cmp = mpz_cmp (section_index[i], ar->as->upper[i]->value.integer);
615 if ((cmp > 0 && forwards)
616 || (cmp < 0 && ! forwards))
618 /* Reset index to start, then loop to advance the next index. */
620 mpz_set (section_index[i], ar->start[i]->value.integer);
622 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
628 mpz_set_si (*offset_ret, 0);
629 mpz_init_set_si (delta, 1);
631 for (i = 0; i < ar->dimen; i++)
633 mpz_sub (tmp, section_index[i], ar->as->lower[i]->value.integer);
634 mpz_mul (tmp, tmp, delta);
635 mpz_add (*offset_ret, tmp, *offset_ret);
637 mpz_sub (tmp, ar->as->upper[i]->value.integer,
638 ar->as->lower[i]->value.integer);
639 mpz_add_ui (tmp, tmp, 1);
640 mpz_mul (delta, tmp, delta);
647 /* Rearrange a structure constructor so the elements are in the specified
648 order. Also insert NULL entries if necessary. */
651 formalize_structure_cons (gfc_expr * expr)
653 gfc_constructor *head;
654 gfc_constructor *tail;
655 gfc_constructor *cur;
656 gfc_constructor *last;
658 gfc_component *order;
660 c = expr->value.constructor;
662 /* Constructor is already formalized. */
663 if (c->n.component == NULL)
667 for (order = expr->ts.derived->components; order; order = order->next)
669 /* Find the next component. */
672 while (cur != NULL && cur->n.component != order)
680 /* Create a new one. */
681 cur = gfc_get_constructor ();
685 /* Remove it from the chain. */
689 last->next = cur->next;
692 formalize_init_expr (cur->expr);
695 /* Add it to the new constructor. */
704 gcc_assert (c == NULL);
705 expr->value.constructor = head;
709 /* Make sure an initialization expression is in normalized form. Ie. all
710 elements of the constructors are in the correct order. */
713 formalize_init_expr (gfc_expr * expr)
721 type = expr->expr_type;
725 c = expr->value.constructor;
728 formalize_init_expr (c->expr);
734 formalize_structure_cons (expr);
743 /* Resolve symbol's initial value after all data statement. */
746 gfc_formalize_init_value (gfc_symbol *sym)
748 formalize_init_expr (sym->value);
752 /* Get the integer value into RET_AS and SECTION from AS and AR, and return
756 gfc_get_section_index (gfc_array_ref *ar, mpz_t *section_index, mpz_t *offset)
762 mpz_set_si (*offset, 0);
764 mpz_init_set_si (delta, 1);
765 for (i = 0; i < ar->dimen; i++)
767 mpz_init (section_index[i]);
768 switch (ar->dimen_type[i])
774 mpz_sub (tmp, ar->start[i]->value.integer,
775 ar->as->lower[i]->value.integer);
776 mpz_mul (tmp, tmp, delta);
777 mpz_add (*offset, tmp, *offset);
778 mpz_set (section_index[i], ar->start[i]->value.integer);
781 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
785 gfc_internal_error ("TODO: Vector sections in data statements");
791 mpz_sub (tmp, ar->as->upper[i]->value.integer,
792 ar->as->lower[i]->value.integer);
793 mpz_add_ui (tmp, tmp, 1);
794 mpz_mul (delta, tmp, delta);