1 /* Supporting functions for resolving DATA statement.
2 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
3 Contributed by Lifang Zeng <zlf605@hotmail.com>
5 This file is part of GCC.
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 2, or (at your option) any later
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
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor,Boston, MA
23 /* Notes for DATA statement implementation:
25 We first assign initial value to each symbol by gfc_assign_data_value
26 during resolveing DATA statement. Refer to check_data_variable and
27 traverse_data_list in resolve.c.
29 The complexity exists in the handling of array section, implied do
30 and array of struct appeared in DATA statement.
32 We call gfc_conv_structure, gfc_con_array_array_initializer,
33 etc., to convert the initial value. Refer to trans-expr.c and
39 static void formalize_init_expr (gfc_expr *);
41 /* Calculate the array element offset. */
44 get_array_index (gfc_array_ref * ar, mpz_t * offset)
53 mpz_set_si (*offset, 0);
54 mpz_init_set_si (delta, 1);
55 for (i = 0; i < ar->dimen; i++)
57 e = gfc_copy_expr (ar->start[i]);
58 re = gfc_simplify_expr (e, 1);
60 if ((gfc_is_constant_expr (ar->as->lower[i]) == 0)
61 || (gfc_is_constant_expr (ar->as->upper[i]) == 0)
62 || (gfc_is_constant_expr (e) == 0))
63 gfc_error ("non-constant array in DATA statement %L.", &ar->where);
64 mpz_set (tmp, e->value.integer);
65 mpz_sub (tmp, tmp, ar->as->lower[i]->value.integer);
66 mpz_mul (tmp, tmp, delta);
67 mpz_add (*offset, tmp, *offset);
69 mpz_sub (tmp, ar->as->upper[i]->value.integer,
70 ar->as->lower[i]->value.integer);
71 mpz_add_ui (tmp, tmp, 1);
72 mpz_mul (delta, tmp, delta);
79 /* Find if there is a constructor which offset is equal to OFFSET. */
81 static gfc_constructor *
82 find_con_by_offset (mpz_t offset, gfc_constructor *con)
85 gfc_constructor *ret = NULL;
89 for (; con; con = con->next)
91 int cmp = mpz_cmp (offset, con->n.offset);
93 /* We retain a sorted list, so if we're too large, we're done. */
97 /* Yaye for exact matches. */
104 /* If the constructor element is a range, match any element. */
105 if (mpz_cmp_ui (con->repeat, 1) > 0)
107 mpz_add (tmp, con->n.offset, con->repeat);
108 if (mpz_cmp (offset, tmp) < 0)
121 /* Find if there is a constructor which component is equal to COM. */
123 static gfc_constructor *
124 find_con_by_component (gfc_component *com, gfc_constructor *con)
126 for (; con; con = con->next)
128 if (com == con->n.component)
135 /* Create a character type initialization expression from RVALUE.
136 TS [and REF] describe [the substring of] the variable being initialized.
137 INIT is thh existing initializer, not NULL. Initialization is performed
138 according to normal assignment rules. */
141 create_character_intializer (gfc_expr * init, gfc_typespec * ts,
142 gfc_ref * ref, gfc_expr * rvalue)
149 gfc_extract_int (ts->cl->length, &len);
153 /* Create a new initializer. */
154 init = gfc_get_expr ();
155 init->expr_type = EXPR_CONSTANT;
158 dest = gfc_getmem (len);
159 init->value.character.length = len;
160 init->value.character.string = dest;
161 /* Blank the string if we're only setting a substring. */
163 memset (dest, ' ', len);
166 dest = init->value.character.string;
170 gcc_assert (ref->type == REF_SUBSTRING);
172 /* Only set a substring of the destination. Fortran substring bounds
173 are one-based [start, end], we want zero based [start, end). */
174 gfc_extract_int (ref->u.ss.start, &start);
176 gfc_extract_int (ref->u.ss.end, &end);
180 /* Set the whole string. */
185 /* Copy the initial value. */
186 len = rvalue->value.character.length;
187 if (len > end - start)
189 memcpy (&dest[start], rvalue->value.character.string, len);
191 /* Pad with spaces. Substrings will already be blanked. */
192 if (len < end - start && ref == NULL)
193 memset (&dest[start + len], ' ', end - (start + len));
198 /* Assign the initial value RVALUE to LVALUE's symbol->value. If the
199 LVALUE already has an initialization, we extend this, otherwise we
203 gfc_assign_data_value (gfc_expr * lvalue, gfc_expr * rvalue, mpz_t index)
208 gfc_constructor *con;
209 gfc_constructor *last_con;
211 gfc_typespec *last_ts;
214 symbol = lvalue->symtree->n.sym;
215 init = symbol->value;
216 last_ts = &symbol->ts;
218 mpz_init_set_si (offset, 0);
220 /* Find/create the parent expressions for subobject references. */
221 for (ref = lvalue->ref; ref; ref = ref->next)
223 /* Break out of the loop if we find a substring. */
224 if (ref->type == REF_SUBSTRING)
226 /* A substring should always br the last subobject reference. */
227 gcc_assert (ref->next == NULL);
231 /* Use the existing initializer expression if it exists. Otherwise
234 expr = gfc_get_expr ();
238 /* Find or create this element. */
244 /* The element typespec will be the same as the array
247 /* Setup the expression to hold the constructor. */
248 expr->expr_type = EXPR_ARRAY;
249 expr->rank = ref->u.ar.as->rank;
252 gcc_assert (expr->expr_type == EXPR_ARRAY);
254 if (ref->u.ar.type == AR_ELEMENT)
255 get_array_index (&ref->u.ar, &offset);
257 mpz_set (offset, index);
259 /* Find the same element in the existing constructor. */
260 con = expr->value.constructor;
261 con = find_con_by_offset (offset, con);
265 /* Create a new constructor. */
266 con = gfc_get_constructor ();
267 mpz_set (con->n.offset, offset);
268 gfc_insert_constructor (expr, con);
275 /* Setup the expression to hold the constructor. */
276 expr->expr_type = EXPR_STRUCTURE;
277 expr->ts.type = BT_DERIVED;
278 expr->ts.derived = ref->u.c.sym;
281 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
282 last_ts = &ref->u.c.component->ts;
284 /* Find the same element in the existing constructor. */
285 con = expr->value.constructor;
286 con = find_con_by_component (ref->u.c.component, con);
290 /* Create a new constructor. */
291 con = gfc_get_constructor ();
292 con->n.component = ref->u.c.component;
293 con->next = expr->value.constructor;
294 expr->value.constructor = con;
304 /* Point the container at the new expression. */
305 if (last_con == NULL)
306 symbol->value = expr;
308 last_con->expr = expr;
314 if (ref || last_ts->type == BT_CHARACTER)
315 expr = create_character_intializer (init, last_ts, ref, rvalue);
318 /* Overwriting an existing initializer is non-standard but usually only
319 provokes a warning from other compilers. */
322 /* Order in which the expressions arrive here depends on whether they
323 are from data statements or F95 style declarations. Therefore,
324 check which is the most recent. */
325 expr = (init->where.lb->linenum > rvalue->where.lb->linenum) ?
327 gfc_notify_std (GFC_STD_GNU, "Extension: re-initialization "
328 "of '%s' at %L", symbol->name, &expr->where);
332 expr = gfc_copy_expr (rvalue);
333 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
334 gfc_convert_type (expr, &lvalue->ts, 0);
337 if (last_con == NULL)
338 symbol->value = expr;
340 last_con->expr = expr;
343 /* Similarly, but initialize REPEAT consecutive values in LVALUE the same
344 value in RVALUE. For the nonce, LVALUE must refer to a full array, not
348 gfc_assign_data_value_range (gfc_expr * lvalue, gfc_expr * rvalue,
349 mpz_t index, mpz_t repeat)
352 gfc_expr *init, *expr;
353 gfc_constructor *con, *last_con;
355 gfc_typespec *last_ts;
358 symbol = lvalue->symtree->n.sym;
359 init = symbol->value;
360 last_ts = &symbol->ts;
362 mpz_init_set_si (offset, 0);
364 /* Find/create the parent expressions for subobject references. */
365 for (ref = lvalue->ref; ref; ref = ref->next)
367 /* Use the existing initializer expression if it exists.
368 Otherwise create a new one. */
370 expr = gfc_get_expr ();
374 /* Find or create this element. */
380 /* The element typespec will be the same as the array
383 /* Setup the expression to hold the constructor. */
384 expr->expr_type = EXPR_ARRAY;
385 expr->rank = ref->u.ar.as->rank;
388 gcc_assert (expr->expr_type == EXPR_ARRAY);
390 if (ref->u.ar.type == AR_ELEMENT)
392 get_array_index (&ref->u.ar, &offset);
394 /* This had better not be the bottom of the reference.
395 We can still get to a full array via a component. */
396 gcc_assert (ref->next != NULL);
400 mpz_set (offset, index);
402 /* We're at a full array or an array section. This means
403 that we've better have found a full array, and that we're
404 at the bottom of the reference. */
405 gcc_assert (ref->u.ar.type == AR_FULL);
406 gcc_assert (ref->next == NULL);
409 /* Find the same element in the existing constructor. */
410 con = expr->value.constructor;
411 con = find_con_by_offset (offset, con);
413 /* Create a new constructor. */
416 con = gfc_get_constructor ();
417 mpz_set (con->n.offset, offset);
418 if (ref->next == NULL)
419 mpz_set (con->repeat, repeat);
420 gfc_insert_constructor (expr, con);
423 gcc_assert (ref->next != NULL);
429 /* Setup the expression to hold the constructor. */
430 expr->expr_type = EXPR_STRUCTURE;
431 expr->ts.type = BT_DERIVED;
432 expr->ts.derived = ref->u.c.sym;
435 gcc_assert (expr->expr_type == EXPR_STRUCTURE);
436 last_ts = &ref->u.c.component->ts;
438 /* Find the same element in the existing constructor. */
439 con = expr->value.constructor;
440 con = find_con_by_component (ref->u.c.component, con);
444 /* Create a new constructor. */
445 con = gfc_get_constructor ();
446 con->n.component = ref->u.c.component;
447 con->next = expr->value.constructor;
448 expr->value.constructor = con;
451 /* Since we're only intending to initialize arrays here,
452 there better be an inner reference. */
453 gcc_assert (ref->next != NULL);
463 /* Point the container at the new expression. */
464 if (last_con == NULL)
465 symbol->value = expr;
467 last_con->expr = expr;
473 if (last_ts->type == BT_CHARACTER)
474 expr = create_character_intializer (init, last_ts, NULL, rvalue);
477 /* We should never be overwriting an existing initializer. */
480 expr = gfc_copy_expr (rvalue);
481 if (!gfc_compare_types (&lvalue->ts, &expr->ts))
482 gfc_convert_type (expr, &lvalue->ts, 0);
485 if (last_con == NULL)
486 symbol->value = expr;
488 last_con->expr = expr;
491 /* Modify the index of array section and re-calculate the array offset. */
494 gfc_advance_section (mpz_t *section_index, gfc_array_ref *ar,
503 for (i = 0; i < ar->dimen; i++)
505 if (ar->dimen_type[i] != DIMEN_RANGE)
510 mpz_add (section_index[i], section_index[i],
511 ar->stride[i]->value.integer);
512 if (mpz_cmp_si (ar->stride[i]->value.integer, 0) >= 0)
519 mpz_add_ui (section_index[i], section_index[i], 1);
524 cmp = mpz_cmp (section_index[i], ar->end[i]->value.integer);
526 cmp = mpz_cmp (section_index[i], ar->as->upper[i]->value.integer);
528 if ((cmp > 0 && forwards)
529 || (cmp < 0 && ! forwards))
531 /* Reset index to start, then loop to advance the next index. */
533 mpz_set (section_index[i], ar->start[i]->value.integer);
535 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
541 mpz_set_si (*offset_ret, 0);
542 mpz_init_set_si (delta, 1);
544 for (i = 0; i < ar->dimen; i++)
546 mpz_sub (tmp, section_index[i], ar->as->lower[i]->value.integer);
547 mpz_mul (tmp, tmp, delta);
548 mpz_add (*offset_ret, tmp, *offset_ret);
550 mpz_sub (tmp, ar->as->upper[i]->value.integer,
551 ar->as->lower[i]->value.integer);
552 mpz_add_ui (tmp, tmp, 1);
553 mpz_mul (delta, tmp, delta);
560 /* Rearrange a structure constructor so the elements are in the specified
561 order. Also insert NULL entries if necessary. */
564 formalize_structure_cons (gfc_expr * expr)
566 gfc_constructor *head;
567 gfc_constructor *tail;
568 gfc_constructor *cur;
569 gfc_constructor *last;
571 gfc_component *order;
573 c = expr->value.constructor;
575 /* Constructor is already formalized. */
576 if (c->n.component == NULL)
580 for (order = expr->ts.derived->components; order; order = order->next)
582 /* Find the next component. */
585 while (cur != NULL && cur->n.component != order)
593 /* Create a new one. */
594 cur = gfc_get_constructor ();
598 /* Remove it from the chain. */
602 last->next = cur->next;
605 formalize_init_expr (cur->expr);
608 /* Add it to the new constructor. */
617 gcc_assert (c == NULL);
618 expr->value.constructor = head;
622 /* Make sure an initialization expression is in normalized form. Ie. all
623 elements of the constructors are in the correct order. */
626 formalize_init_expr (gfc_expr * expr)
634 type = expr->expr_type;
638 c = expr->value.constructor;
641 formalize_init_expr (c->expr);
647 formalize_structure_cons (expr);
656 /* Resolve symbol's initial value after all data statement. */
659 gfc_formalize_init_value (gfc_symbol *sym)
661 formalize_init_expr (sym->value);
665 /* Get the integer value into RET_AS and SECTION from AS and AR, and return
669 gfc_get_section_index (gfc_array_ref *ar, mpz_t *section_index, mpz_t *offset)
675 mpz_set_si (*offset, 0);
677 mpz_init_set_si (delta, 1);
678 for (i = 0; i < ar->dimen; i++)
680 mpz_init (section_index[i]);
681 switch (ar->dimen_type[i])
687 mpz_sub (tmp, ar->start[i]->value.integer,
688 ar->as->lower[i]->value.integer);
689 mpz_mul (tmp, tmp, delta);
690 mpz_add (*offset, tmp, *offset);
691 mpz_set (section_index[i], ar->start[i]->value.integer);
694 mpz_set (section_index[i], ar->as->lower[i]->value.integer);
698 gfc_internal_error ("TODO: Vector sections in data statements");
704 mpz_sub (tmp, ar->as->upper[i]->value.integer,
705 ar->as->lower[i]->value.integer);
706 mpz_add_ui (tmp, tmp, 1);
707 mpz_mul (delta, tmp, delta);