/* Array things Copyright (C) 2000, 2001, 2002, 2004, 2005 Free Software Foundation, Inc. Contributed by Andy Vaught This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "config.h" #include "system.h" #include "gfortran.h" #include "match.h" /* This parameter is the size of the largest array constructor that we will expand to an array constructor without iterators. Constructors larger than this will remain in the iterator form. */ #define GFC_MAX_AC_EXPAND 65535 /**************** Array reference matching subroutines *****************/ /* Copy an array reference structure. */ gfc_array_ref * gfc_copy_array_ref (gfc_array_ref * src) { gfc_array_ref *dest; int i; if (src == NULL) return NULL; dest = gfc_get_array_ref (); *dest = *src; for (i = 0; i < GFC_MAX_DIMENSIONS; i++) { dest->start[i] = gfc_copy_expr (src->start[i]); dest->end[i] = gfc_copy_expr (src->end[i]); dest->stride[i] = gfc_copy_expr (src->stride[i]); } dest->offset = gfc_copy_expr (src->offset); return dest; } /* Match a single dimension of an array reference. This can be a single element or an array section. Any modifications we've made to the ar structure are cleaned up by the caller. If the init is set, we require the subscript to be a valid initialization expression. */ static match match_subscript (gfc_array_ref * ar, int init) { match m; int i; i = ar->dimen; ar->c_where[i] = gfc_current_locus; ar->start[i] = ar->end[i] = ar->stride[i] = NULL; /* We can't be sure of the difference between DIMEN_ELEMENT and DIMEN_VECTOR until we know the type of the element itself at resolution time. */ ar->dimen_type[i] = DIMEN_UNKNOWN; if (gfc_match_char (':') == MATCH_YES) goto end_element; /* Get start element. */ if (init) m = gfc_match_init_expr (&ar->start[i]); else m = gfc_match_expr (&ar->start[i]); if (m == MATCH_NO) gfc_error ("Expected array subscript at %C"); if (m != MATCH_YES) return MATCH_ERROR; if (gfc_match_char (':') == MATCH_NO) return MATCH_YES; /* Get an optional end element. Because we've seen the colon, we definitely have a range along this dimension. */ end_element: ar->dimen_type[i] = DIMEN_RANGE; if (init) m = gfc_match_init_expr (&ar->end[i]); else m = gfc_match_expr (&ar->end[i]); if (m == MATCH_ERROR) return MATCH_ERROR; /* See if we have an optional stride. */ if (gfc_match_char (':') == MATCH_YES) { m = init ? gfc_match_init_expr (&ar->stride[i]) : gfc_match_expr (&ar->stride[i]); if (m == MATCH_NO) gfc_error ("Expected array subscript stride at %C"); if (m != MATCH_YES) return MATCH_ERROR; } return MATCH_YES; } /* Match an array reference, whether it is the whole array or a particular elements or a section. If init is set, the reference has to consist of init expressions. */ match gfc_match_array_ref (gfc_array_ref * ar, gfc_array_spec * as, int init) { match m; memset (ar, '\0', sizeof (ar)); ar->where = gfc_current_locus; ar->as = as; if (gfc_match_char ('(') != MATCH_YES) { ar->type = AR_FULL; ar->dimen = 0; return MATCH_YES; } ar->type = AR_UNKNOWN; for (ar->dimen = 0; ar->dimen < GFC_MAX_DIMENSIONS; ar->dimen++) { m = match_subscript (ar, init); if (m == MATCH_ERROR) goto error; if (gfc_match_char (')') == MATCH_YES) goto matched; if (gfc_match_char (',') != MATCH_YES) { gfc_error ("Invalid form of array reference at %C"); goto error; } } gfc_error ("Array reference at %C cannot have more than %d dimensions", GFC_MAX_DIMENSIONS); error: return MATCH_ERROR; matched: ar->dimen++; return MATCH_YES; } /************** Array specification matching subroutines ***************/ /* Free all of the expressions associated with array bounds specifications. */ void gfc_free_array_spec (gfc_array_spec * as) { int i; if (as == NULL) return; for (i = 0; i < as->rank; i++) { gfc_free_expr (as->lower[i]); gfc_free_expr (as->upper[i]); } gfc_free (as); } /* Take an array bound, resolves the expression, that make up the shape and check associated constraints. */ static try resolve_array_bound (gfc_expr * e, int check_constant) { if (e == NULL) return SUCCESS; if (gfc_resolve_expr (e) == FAILURE || gfc_specification_expr (e) == FAILURE) return FAILURE; if (check_constant && gfc_is_constant_expr (e) == 0) { gfc_error ("Variable '%s' at %L in this context must be constant", e->symtree->n.sym->name, &e->where); return FAILURE; } return SUCCESS; } /* Takes an array specification, resolves the expressions that make up the shape and make sure everything is integral. */ try gfc_resolve_array_spec (gfc_array_spec * as, int check_constant) { gfc_expr *e; int i; if (as == NULL) return SUCCESS; for (i = 0; i < as->rank; i++) { e = as->lower[i]; if (resolve_array_bound (e, check_constant) == FAILURE) return FAILURE; e = as->upper[i]; if (resolve_array_bound (e, check_constant) == FAILURE) return FAILURE; } return SUCCESS; } /* Match a single array element specification. The return values as well as the upper and lower bounds of the array spec are filled in according to what we see on the input. The caller makes sure individual specifications make sense as a whole. Parsed Lower Upper Returned ------------------------------------ : NULL NULL AS_DEFERRED (*) x 1 x AS_EXPLICIT x: x NULL AS_ASSUMED_SHAPE x:y x y AS_EXPLICIT x:* x NULL AS_ASSUMED_SIZE * 1 NULL AS_ASSUMED_SIZE (*) For non-pointer dummy arrays this is AS_ASSUMED_SHAPE. This is fixed during the resolution of formal interfaces. Anything else AS_UNKNOWN. */ static array_type match_array_element_spec (gfc_array_spec * as) { gfc_expr **upper, **lower; match m; lower = &as->lower[as->rank - 1]; upper = &as->upper[as->rank - 1]; if (gfc_match_char ('*') == MATCH_YES) { *lower = gfc_int_expr (1); return AS_ASSUMED_SIZE; } if (gfc_match_char (':') == MATCH_YES) return AS_DEFERRED; m = gfc_match_expr (upper); if (m == MATCH_NO) gfc_error ("Expected expression in array specification at %C"); if (m != MATCH_YES) return AS_UNKNOWN; if (gfc_match_char (':') == MATCH_NO) { *lower = gfc_int_expr (1); return AS_EXPLICIT; } *lower = *upper; *upper = NULL; if (gfc_match_char ('*') == MATCH_YES) return AS_ASSUMED_SIZE; m = gfc_match_expr (upper); if (m == MATCH_ERROR) return AS_UNKNOWN; if (m == MATCH_NO) return AS_ASSUMED_SHAPE; /* If the size is negative in this dimension, set it to zero. */ if ((*lower)->expr_type == EXPR_CONSTANT && (*upper)->expr_type == EXPR_CONSTANT && mpz_cmp ((*upper)->value.integer, (*lower)->value.integer) < 0) { gfc_free_expr (*upper); *upper = gfc_copy_expr (*lower); mpz_sub_ui ((*upper)->value.integer, (*upper)->value.integer, 1); } return AS_EXPLICIT; } /* Matches an array specification, incidentally figuring out what sort it is. */ match gfc_match_array_spec (gfc_array_spec ** asp) { array_type current_type; gfc_array_spec *as; int i; if (gfc_match_char ('(') != MATCH_YES) { *asp = NULL; return MATCH_NO; } as = gfc_get_array_spec (); for (i = 0; i < GFC_MAX_DIMENSIONS; i++) { as->lower[i] = NULL; as->upper[i] = NULL; } as->rank = 1; for (;;) { current_type = match_array_element_spec (as); if (as->rank == 1) { if (current_type == AS_UNKNOWN) goto cleanup; as->type = current_type; } else switch (as->type) { /* See how current spec meshes with the existing */ case AS_UNKNOWN: goto cleanup; case AS_EXPLICIT: if (current_type == AS_ASSUMED_SIZE) { as->type = AS_ASSUMED_SIZE; break; } if (current_type == AS_EXPLICIT) break; gfc_error ("Bad array specification for an explicitly shaped array" " at %C"); goto cleanup; case AS_ASSUMED_SHAPE: if ((current_type == AS_ASSUMED_SHAPE) || (current_type == AS_DEFERRED)) break; gfc_error ("Bad array specification for assumed shape array at %C"); goto cleanup; case AS_DEFERRED: if (current_type == AS_DEFERRED) break; if (current_type == AS_ASSUMED_SHAPE) { as->type = AS_ASSUMED_SHAPE; break; } gfc_error ("Bad specification for deferred shape array at %C"); goto cleanup; case AS_ASSUMED_SIZE: gfc_error ("Bad specification for assumed size array at %C"); goto cleanup; } if (gfc_match_char (')') == MATCH_YES) break; if (gfc_match_char (',') != MATCH_YES) { gfc_error ("Expected another dimension in array declaration at %C"); goto cleanup; } if (as->rank >= GFC_MAX_DIMENSIONS) { gfc_error ("Array specification at %C has more than %d dimensions", GFC_MAX_DIMENSIONS); goto cleanup; } as->rank++; } /* If a lower bounds of an assumed shape array is blank, put in one. */ if (as->type == AS_ASSUMED_SHAPE) { for (i = 0; i < as->rank; i++) { if (as->lower[i] == NULL) as->lower[i] = gfc_int_expr (1); } } *asp = as; return MATCH_YES; cleanup: /* Something went wrong. */ gfc_free_array_spec (as); return MATCH_ERROR; } /* Given a symbol and an array specification, modify the symbol to have that array specification. The error locus is needed in case something goes wrong. On failure, the caller must free the spec. */ try gfc_set_array_spec (gfc_symbol * sym, gfc_array_spec * as, locus * error_loc) { if (as == NULL) return SUCCESS; if (gfc_add_dimension (&sym->attr, sym->name, error_loc) == FAILURE) return FAILURE; sym->as = as; return SUCCESS; } /* Copy an array specification. */ gfc_array_spec * gfc_copy_array_spec (gfc_array_spec * src) { gfc_array_spec *dest; int i; if (src == NULL) return NULL; dest = gfc_get_array_spec (); *dest = *src; for (i = 0; i < dest->rank; i++) { dest->lower[i] = gfc_copy_expr (dest->lower[i]); dest->upper[i] = gfc_copy_expr (dest->upper[i]); } return dest; } /* Returns nonzero if the two expressions are equal. Only handles integer constants. */ static int compare_bounds (gfc_expr * bound1, gfc_expr * bound2) { if (bound1 == NULL || bound2 == NULL || bound1->expr_type != EXPR_CONSTANT || bound2->expr_type != EXPR_CONSTANT || bound1->ts.type != BT_INTEGER || bound2->ts.type != BT_INTEGER) gfc_internal_error ("gfc_compare_array_spec(): Array spec clobbered"); if (mpz_cmp (bound1->value.integer, bound2->value.integer) == 0) return 1; else return 0; } /* Compares two array specifications. They must be constant or deferred shape. */ int gfc_compare_array_spec (gfc_array_spec * as1, gfc_array_spec * as2) { int i; if (as1 == NULL && as2 == NULL) return 1; if (as1 == NULL || as2 == NULL) return 0; if (as1->rank != as2->rank) return 0; if (as1->rank == 0) return 1; if (as1->type != as2->type) return 0; if (as1->type == AS_EXPLICIT) for (i = 0; i < as1->rank; i++) { if (compare_bounds (as1->lower[i], as2->lower[i]) == 0) return 0; if (compare_bounds (as1->upper[i], as2->upper[i]) == 0) return 0; } return 1; } /****************** Array constructor functions ******************/ /* Start an array constructor. The constructor starts with zero elements and should be appended to by gfc_append_constructor(). */ gfc_expr * gfc_start_constructor (bt type, int kind, locus * where) { gfc_expr *result; result = gfc_get_expr (); result->expr_type = EXPR_ARRAY; result->rank = 1; result->ts.type = type; result->ts.kind = kind; result->where = *where; return result; } /* Given an array constructor expression, append the new expression node onto the constructor. */ void gfc_append_constructor (gfc_expr * base, gfc_expr * new) { gfc_constructor *c; if (base->value.constructor == NULL) base->value.constructor = c = gfc_get_constructor (); else { c = base->value.constructor; while (c->next) c = c->next; c->next = gfc_get_constructor (); c = c->next; } c->expr = new; if (new->ts.type != base->ts.type || new->ts.kind != base->ts.kind) gfc_internal_error ("gfc_append_constructor(): New node has wrong kind"); } /* Given an array constructor expression, insert the new expression's constructor onto the base's one according to the offset. */ void gfc_insert_constructor (gfc_expr * base, gfc_constructor * c1) { gfc_constructor *c, *pre; expr_t type; int t; type = base->expr_type; if (base->value.constructor == NULL) base->value.constructor = c1; else { c = pre = base->value.constructor; while (c) { if (type == EXPR_ARRAY) { t = mpz_cmp (c->n.offset, c1->n.offset); if (t < 0) { pre = c; c = c->next; } else if (t == 0) { gfc_error ("duplicated initializer"); break; } else break; } else { pre = c; c = c->next; } } if (pre != c) { pre->next = c1; c1->next = c; } else { c1->next = c; base->value.constructor = c1; } } } /* Get a new constructor. */ gfc_constructor * gfc_get_constructor (void) { gfc_constructor *c; c = gfc_getmem (sizeof(gfc_constructor)); c->expr = NULL; c->iterator = NULL; c->next = NULL; mpz_init_set_si (c->n.offset, 0); mpz_init_set_si (c->repeat, 0); return c; } /* Free chains of gfc_constructor structures. */ void gfc_free_constructor (gfc_constructor * p) { gfc_constructor *next; if (p == NULL) return; for (; p; p = next) { next = p->next; if (p->expr) gfc_free_expr (p->expr); if (p->iterator != NULL) gfc_free_iterator (p->iterator, 1); mpz_clear (p->n.offset); mpz_clear (p->repeat); gfc_free (p); } } /* Given an expression node that might be an array constructor and a symbol, make sure that no iterators in this or child constructors use the symbol as an implied-DO iterator. Returns nonzero if a duplicate was found. */ static int check_duplicate_iterator (gfc_constructor * c, gfc_symbol * master) { gfc_expr *e; for (; c; c = c->next) { e = c->expr; if (e->expr_type == EXPR_ARRAY && check_duplicate_iterator (e->value.constructor, master)) return 1; if (c->iterator == NULL) continue; if (c->iterator->var->symtree->n.sym == master) { gfc_error ("DO-iterator '%s' at %L is inside iterator of the same name", master->name, &c->where); return 1; } } return 0; } /* Forward declaration because these functions are mutually recursive. */ static match match_array_cons_element (gfc_constructor **); /* Match a list of array elements. */ static match match_array_list (gfc_constructor ** result) { gfc_constructor *p, *head, *tail, *new; gfc_iterator iter; locus old_loc; gfc_expr *e; match m; int n; old_loc = gfc_current_locus; if (gfc_match_char ('(') == MATCH_NO) return MATCH_NO; memset (&iter, '\0', sizeof (gfc_iterator)); head = NULL; m = match_array_cons_element (&head); if (m != MATCH_YES) goto cleanup; tail = head; if (gfc_match_char (',') != MATCH_YES) { m = MATCH_NO; goto cleanup; } for (n = 1;; n++) { m = gfc_match_iterator (&iter, 0); if (m == MATCH_YES) break; if (m == MATCH_ERROR) goto cleanup; m = match_array_cons_element (&new); if (m == MATCH_ERROR) goto cleanup; if (m == MATCH_NO) { if (n > 2) goto syntax; m = MATCH_NO; goto cleanup; /* Could be a complex constant */ } tail->next = new; tail = new; if (gfc_match_char (',') != MATCH_YES) { if (n > 2) goto syntax; m = MATCH_NO; goto cleanup; } } if (gfc_match_char (')') != MATCH_YES) goto syntax; if (check_duplicate_iterator (head, iter.var->symtree->n.sym)) { m = MATCH_ERROR; goto cleanup; } e = gfc_get_expr (); e->expr_type = EXPR_ARRAY; e->where = old_loc; e->value.constructor = head; p = gfc_get_constructor (); p->where = gfc_current_locus; p->iterator = gfc_get_iterator (); *p->iterator = iter; p->expr = e; *result = p; return MATCH_YES; syntax: gfc_error ("Syntax error in array constructor at %C"); m = MATCH_ERROR; cleanup: gfc_free_constructor (head); gfc_free_iterator (&iter, 0); gfc_current_locus = old_loc; return m; } /* Match a single element of an array constructor, which can be a single expression or a list of elements. */ static match match_array_cons_element (gfc_constructor ** result) { gfc_constructor *p; gfc_expr *expr; match m; m = match_array_list (result); if (m != MATCH_NO) return m; m = gfc_match_expr (&expr); if (m != MATCH_YES) return m; p = gfc_get_constructor (); p->where = gfc_current_locus; p->expr = expr; *result = p; return MATCH_YES; } /* Match an array constructor. */ match gfc_match_array_constructor (gfc_expr ** result) { gfc_constructor *head, *tail, *new; gfc_expr *expr; locus where; match m; const char *end_delim; if (gfc_match (" (/") == MATCH_NO) { if (gfc_match (" [") == MATCH_NO) return MATCH_NO; else { if (gfc_notify_std (GFC_STD_F2003, "New in Fortran 2003: [...] " "style array constructors at %C") == FAILURE) return MATCH_ERROR; end_delim = " ]"; } } else end_delim = " /)"; where = gfc_current_locus; head = tail = NULL; if (gfc_match (end_delim) == MATCH_YES) { gfc_error ("Empty array constructor at %C is not allowed"); goto cleanup; } for (;;) { m = match_array_cons_element (&new); if (m == MATCH_ERROR) goto cleanup; if (m == MATCH_NO) goto syntax; if (head == NULL) head = new; else tail->next = new; tail = new; if (gfc_match_char (',') == MATCH_NO) break; } if (gfc_match (end_delim) == MATCH_NO) goto syntax; expr = gfc_get_expr (); expr->expr_type = EXPR_ARRAY; expr->value.constructor = head; /* Size must be calculated at resolution time. */ expr->where = where; expr->rank = 1; *result = expr; return MATCH_YES; syntax: gfc_error ("Syntax error in array constructor at %C"); cleanup: gfc_free_constructor (head); return MATCH_ERROR; } /************** Check array constructors for correctness **************/ /* Given an expression, compare it's type with the type of the current constructor. Returns nonzero if an error was issued. The cons_state variable keeps track of whether the type of the constructor being read or resolved is known to be good, bad or just starting out. */ static gfc_typespec constructor_ts; static enum { CONS_START, CONS_GOOD, CONS_BAD } cons_state; static int check_element_type (gfc_expr * expr) { if (cons_state == CONS_BAD) return 0; /* Suppress further errors */ if (cons_state == CONS_START) { if (expr->ts.type == BT_UNKNOWN) cons_state = CONS_BAD; else { cons_state = CONS_GOOD; constructor_ts = expr->ts; } return 0; } if (gfc_compare_types (&constructor_ts, &expr->ts)) return 0; gfc_error ("Element in %s array constructor at %L is %s", gfc_typename (&constructor_ts), &expr->where, gfc_typename (&expr->ts)); cons_state = CONS_BAD; return 1; } /* Recursive work function for gfc_check_constructor_type(). */ static try check_constructor_type (gfc_constructor * c) { gfc_expr *e; for (; c; c = c->next) { e = c->expr; if (e->expr_type == EXPR_ARRAY) { if (check_constructor_type (e->value.constructor) == FAILURE) return FAILURE; continue; } if (check_element_type (e)) return FAILURE; } return SUCCESS; } /* Check that all elements of an array constructor are the same type. On FAILURE, an error has been generated. */ try gfc_check_constructor_type (gfc_expr * e) { try t; cons_state = CONS_START; gfc_clear_ts (&constructor_ts); t = check_constructor_type (e->value.constructor); if (t == SUCCESS && e->ts.type == BT_UNKNOWN) e->ts = constructor_ts; return t; } typedef struct cons_stack { gfc_iterator *iterator; struct cons_stack *previous; } cons_stack; static cons_stack *base; static try check_constructor (gfc_constructor *, try (*)(gfc_expr *)); /* Check an EXPR_VARIABLE expression in a constructor to make sure that that variable is an iteration variables. */ try gfc_check_iter_variable (gfc_expr * expr) { gfc_symbol *sym; cons_stack *c; sym = expr->symtree->n.sym; for (c = base; c; c = c->previous) if (sym == c->iterator->var->symtree->n.sym) return SUCCESS; return FAILURE; } /* Recursive work function for gfc_check_constructor(). This amounts to calling the check function for each expression in the constructor, giving variables with the names of iterators a pass. */ static try check_constructor (gfc_constructor * c, try (*check_function) (gfc_expr *)) { cons_stack element; gfc_expr *e; try t; for (; c; c = c->next) { e = c->expr; if (e->expr_type != EXPR_ARRAY) { if ((*check_function) (e) == FAILURE) return FAILURE; continue; } element.previous = base; element.iterator = c->iterator; base = &element; t = check_constructor (e->value.constructor, check_function); base = element.previous; if (t == FAILURE) return FAILURE; } /* Nothing went wrong, so all OK. */ return SUCCESS; } /* Checks a constructor to see if it is a particular kind of expression -- specification, restricted, or initialization as determined by the check_function. */ try gfc_check_constructor (gfc_expr * expr, try (*check_function) (gfc_expr *)) { cons_stack *base_save; try t; base_save = base; base = NULL; t = check_constructor (expr->value.constructor, check_function); base = base_save; return t; } /**************** Simplification of array constructors ****************/ iterator_stack *iter_stack; typedef struct { gfc_constructor *new_head, *new_tail; int extract_count, extract_n; gfc_expr *extracted; mpz_t *count; mpz_t *offset; gfc_component *component; mpz_t *repeat; try (*expand_work_function) (gfc_expr *); } expand_info; static expand_info current_expand; static try expand_constructor (gfc_constructor *); /* Work function that counts the number of elements present in a constructor. */ static try count_elements (gfc_expr * e) { mpz_t result; if (e->rank == 0) mpz_add_ui (*current_expand.count, *current_expand.count, 1); else { if (gfc_array_size (e, &result) == FAILURE) { gfc_free_expr (e); return FAILURE; } mpz_add (*current_expand.count, *current_expand.count, result); mpz_clear (result); } gfc_free_expr (e); return SUCCESS; } /* Work function that extracts a particular element from an array constructor, freeing the rest. */ static try extract_element (gfc_expr * e) { if (e->rank != 0) { /* Something unextractable */ gfc_free_expr (e); return FAILURE; } if (current_expand.extract_count == current_expand.extract_n) current_expand.extracted = e; else gfc_free_expr (e); current_expand.extract_count++; return SUCCESS; } /* Work function that constructs a new constructor out of the old one, stringing new elements together. */ static try expand (gfc_expr * e) { if (current_expand.new_head == NULL) current_expand.new_head = current_expand.new_tail = gfc_get_constructor (); else { current_expand.new_tail->next = gfc_get_constructor (); current_expand.new_tail = current_expand.new_tail->next; } current_expand.new_tail->where = e->where; current_expand.new_tail->expr = e; mpz_set (current_expand.new_tail->n.offset, *current_expand.offset); current_expand.new_tail->n.component = current_expand.component; mpz_set (current_expand.new_tail->repeat, *current_expand.repeat); return SUCCESS; } /* Given an initialization expression that is a variable reference, substitute the current value of the iteration variable. */ void gfc_simplify_iterator_var (gfc_expr * e) { iterator_stack *p; for (p = iter_stack; p; p = p->prev) if (e->symtree == p->variable) break; if (p == NULL) return; /* Variable not found */ gfc_replace_expr (e, gfc_int_expr (0)); mpz_set (e->value.integer, p->value); return; } /* Expand an expression with that is inside of a constructor, recursing into other constructors if present. */ static try expand_expr (gfc_expr * e) { if (e->expr_type == EXPR_ARRAY) return expand_constructor (e->value.constructor); e = gfc_copy_expr (e); if (gfc_simplify_expr (e, 1) == FAILURE) { gfc_free_expr (e); return FAILURE; } return current_expand.expand_work_function (e); } static try expand_iterator (gfc_constructor * c) { gfc_expr *start, *end, *step; iterator_stack frame; mpz_t trip; try t; end = step = NULL; t = FAILURE; mpz_init (trip); mpz_init (frame.value); start = gfc_copy_expr (c->iterator->start); if (gfc_simplify_expr (start, 1) == FAILURE) goto cleanup; if (start->expr_type != EXPR_CONSTANT || start->ts.type != BT_INTEGER) goto cleanup; end = gfc_copy_expr (c->iterator->end); if (gfc_simplify_expr (end, 1) == FAILURE) goto cleanup; if (end->expr_type != EXPR_CONSTANT || end->ts.type != BT_INTEGER) goto cleanup; step = gfc_copy_expr (c->iterator->step); if (gfc_simplify_expr (step, 1) == FAILURE) goto cleanup; if (step->expr_type != EXPR_CONSTANT || step->ts.type != BT_INTEGER) goto cleanup; if (mpz_sgn (step->value.integer) == 0) { gfc_error ("Iterator step at %L cannot be zero", &step->where); goto cleanup; } /* Calculate the trip count of the loop. */ mpz_sub (trip, end->value.integer, start->value.integer); mpz_add (trip, trip, step->value.integer); mpz_tdiv_q (trip, trip, step->value.integer); mpz_set (frame.value, start->value.integer); frame.prev = iter_stack; frame.variable = c->iterator->var->symtree; iter_stack = &frame; while (mpz_sgn (trip) > 0) { if (expand_expr (c->expr) == FAILURE) goto cleanup; mpz_add (frame.value, frame.value, step->value.integer); mpz_sub_ui (trip, trip, 1); } t = SUCCESS; cleanup: gfc_free_expr (start); gfc_free_expr (end); gfc_free_expr (step); mpz_clear (trip); mpz_clear (frame.value); iter_stack = frame.prev; return t; } /* Expand a constructor into constant constructors without any iterators, calling the work function for each of the expanded expressions. The work function needs to either save or free the passed expression. */ static try expand_constructor (gfc_constructor * c) { gfc_expr *e; for (; c; c = c->next) { if (c->iterator != NULL) { if (expand_iterator (c) == FAILURE) return FAILURE; continue; } e = c->expr; if (e->expr_type == EXPR_ARRAY) { if (expand_constructor (e->value.constructor) == FAILURE) return FAILURE; continue; } e = gfc_copy_expr (e); if (gfc_simplify_expr (e, 1) == FAILURE) { gfc_free_expr (e); return FAILURE; } current_expand.offset = &c->n.offset; current_expand.component = c->n.component; current_expand.repeat = &c->repeat; if (current_expand.expand_work_function (e) == FAILURE) return FAILURE; } return SUCCESS; } /* Top level subroutine for expanding constructors. We only expand constructor if they are small enough. */ try gfc_expand_constructor (gfc_expr * e) { expand_info expand_save; gfc_expr *f; try rc; f = gfc_get_array_element (e, GFC_MAX_AC_EXPAND); if (f != NULL) { gfc_free_expr (f); return SUCCESS; } expand_save = current_expand; current_expand.new_head = current_expand.new_tail = NULL; iter_stack = NULL; current_expand.expand_work_function = expand; if (expand_constructor (e->value.constructor) == FAILURE) { gfc_free_constructor (current_expand.new_head); rc = FAILURE; goto done; } gfc_free_constructor (e->value.constructor); e->value.constructor = current_expand.new_head; rc = SUCCESS; done: current_expand = expand_save; return rc; } /* Work function for checking that an element of a constructor is a constant, after removal of any iteration variables. We return FAILURE if not so. */ static try constant_element (gfc_expr * e) { int rv; rv = gfc_is_constant_expr (e); gfc_free_expr (e); return rv ? SUCCESS : FAILURE; } /* Given an array constructor, determine if the constructor is constant or not by expanding it and making sure that all elements are constants. This is a bit of a hack since something like (/ (i, i=1,100000000) /) will take a while as* opposed to a more clever function that traverses the expression tree. FIXME. */ int gfc_constant_ac (gfc_expr * e) { expand_info expand_save; try rc; iter_stack = NULL; expand_save = current_expand; current_expand.expand_work_function = constant_element; rc = expand_constructor (e->value.constructor); current_expand = expand_save; if (rc == FAILURE) return 0; return 1; } /* Returns nonzero if an array constructor has been completely expanded (no iterators) and zero if iterators are present. */ int gfc_expanded_ac (gfc_expr * e) { gfc_constructor *p; if (e->expr_type == EXPR_ARRAY) for (p = e->value.constructor; p; p = p->next) if (p->iterator != NULL || !gfc_expanded_ac (p->expr)) return 0; return 1; } /*************** Type resolution of array constructors ***************/ /* Recursive array list resolution function. All of the elements must be of the same type. */ static try resolve_array_list (gfc_constructor * p) { try t; t = SUCCESS; for (; p; p = p->next) { if (p->iterator != NULL && gfc_resolve_iterator (p->iterator, false) == FAILURE) t = FAILURE; if (gfc_resolve_expr (p->expr) == FAILURE) t = FAILURE; } return t; } /* Resolve character array constructor. If it is a constant character array and not specified character length, update character length to the maximum of its element constructors' length. */ void gfc_resolve_character_array_constructor (gfc_expr * expr) { gfc_constructor * p; int max_length; gcc_assert (expr->expr_type == EXPR_ARRAY); gcc_assert (expr->ts.type == BT_CHARACTER); max_length = -1; if (expr->ts.cl == NULL) { for (p = expr->value.constructor; p; p = p->next) if (p->expr->ts.cl != NULL) { /* Ensure that if there is a char_len around that it is used; otherwise the middle-end confuses them! */ expr->ts.cl = p->expr->ts.cl; goto got_charlen; } expr->ts.cl = gfc_get_charlen (); expr->ts.cl->next = gfc_current_ns->cl_list; gfc_current_ns->cl_list = expr->ts.cl; } got_charlen: if (expr->ts.cl->length == NULL) { /* Find the maximum length of the elements. Do nothing for variable array constructor, unless the character length is constant or there is a constant substring reference. */ for (p = expr->value.constructor; p; p = p->next) { gfc_ref *ref; for (ref = p->expr->ref; ref; ref = ref->next) if (ref->type == REF_SUBSTRING && ref->u.ss.start->expr_type == EXPR_CONSTANT && ref->u.ss.end->expr_type == EXPR_CONSTANT) break; if (p->expr->expr_type == EXPR_CONSTANT) max_length = MAX (p->expr->value.character.length, max_length); else if (ref) max_length = MAX ((int)(mpz_get_ui (ref->u.ss.end->value.integer) - mpz_get_ui (ref->u.ss.start->value.integer)) + 1, max_length); else if (p->expr->ts.cl && p->expr->ts.cl->length && p->expr->ts.cl->length->expr_type == EXPR_CONSTANT) max_length = MAX ((int)mpz_get_si (p->expr->ts.cl->length->value.integer), max_length); else return; } if (max_length != -1) { /* Update the character length of the array constructor. */ expr->ts.cl->length = gfc_int_expr (max_length); /* Update the element constructors. */ for (p = expr->value.constructor; p; p = p->next) if (p->expr->expr_type == EXPR_CONSTANT) gfc_set_constant_character_len (max_length, p->expr, true); } } } /* Resolve all of the expressions in an array list. */ try gfc_resolve_array_constructor (gfc_expr * expr) { try t; t = resolve_array_list (expr->value.constructor); if (t == SUCCESS) t = gfc_check_constructor_type (expr); if (t == SUCCESS && expr->ts.type == BT_CHARACTER) gfc_resolve_character_array_constructor (expr); return t; } /* Copy an iterator structure. */ static gfc_iterator * copy_iterator (gfc_iterator * src) { gfc_iterator *dest; if (src == NULL) return NULL; dest = gfc_get_iterator (); dest->var = gfc_copy_expr (src->var); dest->start = gfc_copy_expr (src->start); dest->end = gfc_copy_expr (src->end); dest->step = gfc_copy_expr (src->step); return dest; } /* Copy a constructor structure. */ gfc_constructor * gfc_copy_constructor (gfc_constructor * src) { gfc_constructor *dest; gfc_constructor *tail; if (src == NULL) return NULL; dest = tail = NULL; while (src) { if (dest == NULL) dest = tail = gfc_get_constructor (); else { tail->next = gfc_get_constructor (); tail = tail->next; } tail->where = src->where; tail->expr = gfc_copy_expr (src->expr); tail->iterator = copy_iterator (src->iterator); mpz_set (tail->n.offset, src->n.offset); tail->n.component = src->n.component; mpz_set (tail->repeat, src->repeat); src = src->next; } return dest; } /* Given an array expression and an element number (starting at zero), return a pointer to the array element. NULL is returned if the size of the array has been exceeded. The expression node returned remains a part of the array and should not be freed. Access is not efficient at all, but this is another place where things do not have to be particularly fast. */ gfc_expr * gfc_get_array_element (gfc_expr * array, int element) { expand_info expand_save; gfc_expr *e; try rc; expand_save = current_expand; current_expand.extract_n = element; current_expand.expand_work_function = extract_element; current_expand.extracted = NULL; current_expand.extract_count = 0; iter_stack = NULL; rc = expand_constructor (array->value.constructor); e = current_expand.extracted; current_expand = expand_save; if (rc == FAILURE) return NULL; return e; } /********* Subroutines for determining the size of an array *********/ /* These are needed just to accommodate RESHAPE(). There are no diagnostics here, we just return a negative number if something goes wrong. */ /* Get the size of single dimension of an array specification. The array is guaranteed to be one dimensional. */ static try spec_dimen_size (gfc_array_spec * as, int dimen, mpz_t * result) { if (as == NULL) return FAILURE; if (dimen < 0 || dimen > as->rank - 1) gfc_internal_error ("spec_dimen_size(): Bad dimension"); if (as->type != AS_EXPLICIT || as->lower[dimen]->expr_type != EXPR_CONSTANT || as->upper[dimen]->expr_type != EXPR_CONSTANT) return FAILURE; mpz_init (*result); mpz_sub (*result, as->upper[dimen]->value.integer, as->lower[dimen]->value.integer); mpz_add_ui (*result, *result, 1); return SUCCESS; } try spec_size (gfc_array_spec * as, mpz_t * result) { mpz_t size; int d; mpz_init_set_ui (*result, 1); for (d = 0; d < as->rank; d++) { if (spec_dimen_size (as, d, &size) == FAILURE) { mpz_clear (*result); return FAILURE; } mpz_mul (*result, *result, size); mpz_clear (size); } return SUCCESS; } /* Get the number of elements in an array section. */ static try ref_dimen_size (gfc_array_ref * ar, int dimen, mpz_t * result) { mpz_t upper, lower, stride; try t; if (dimen < 0 || ar == NULL || dimen > ar->dimen - 1) gfc_internal_error ("ref_dimen_size(): Bad dimension"); switch (ar->dimen_type[dimen]) { case DIMEN_ELEMENT: mpz_init (*result); mpz_set_ui (*result, 1); t = SUCCESS; break; case DIMEN_VECTOR: t = gfc_array_size (ar->start[dimen], result); /* Recurse! */ break; case DIMEN_RANGE: mpz_init (upper); mpz_init (lower); mpz_init (stride); t = FAILURE; if (ar->start[dimen] == NULL) { if (ar->as->lower[dimen] == NULL || ar->as->lower[dimen]->expr_type != EXPR_CONSTANT) goto cleanup; mpz_set (lower, ar->as->lower[dimen]->value.integer); } else { if (ar->start[dimen]->expr_type != EXPR_CONSTANT) goto cleanup; mpz_set (lower, ar->start[dimen]->value.integer); } if (ar->end[dimen] == NULL) { if (ar->as->upper[dimen] == NULL || ar->as->upper[dimen]->expr_type != EXPR_CONSTANT) goto cleanup; mpz_set (upper, ar->as->upper[dimen]->value.integer); } else { if (ar->end[dimen]->expr_type != EXPR_CONSTANT) goto cleanup; mpz_set (upper, ar->end[dimen]->value.integer); } if (ar->stride[dimen] == NULL) mpz_set_ui (stride, 1); else { if (ar->stride[dimen]->expr_type != EXPR_CONSTANT) goto cleanup; mpz_set (stride, ar->stride[dimen]->value.integer); } mpz_init (*result); mpz_sub (*result, upper, lower); mpz_add (*result, *result, stride); mpz_div (*result, *result, stride); /* Zero stride caught earlier. */ if (mpz_cmp_ui (*result, 0) < 0) mpz_set_ui (*result, 0); t = SUCCESS; cleanup: mpz_clear (upper); mpz_clear (lower); mpz_clear (stride); return t; default: gfc_internal_error ("ref_dimen_size(): Bad dimen_type"); } return t; } static try ref_size (gfc_array_ref * ar, mpz_t * result) { mpz_t size; int d; mpz_init_set_ui (*result, 1); for (d = 0; d < ar->dimen; d++) { if (ref_dimen_size (ar, d, &size) == FAILURE) { mpz_clear (*result); return FAILURE; } mpz_mul (*result, *result, size); mpz_clear (size); } return SUCCESS; } /* Given an array expression and a dimension, figure out how many elements it has along that dimension. Returns SUCCESS if we were able to return a result in the 'result' variable, FAILURE otherwise. */ try gfc_array_dimen_size (gfc_expr * array, int dimen, mpz_t * result) { gfc_ref *ref; int i; if (dimen < 0 || array == NULL || dimen > array->rank - 1) gfc_internal_error ("gfc_array_dimen_size(): Bad dimension"); switch (array->expr_type) { case EXPR_VARIABLE: case EXPR_FUNCTION: for (ref = array->ref; ref; ref = ref->next) { if (ref->type != REF_ARRAY) continue; if (ref->u.ar.type == AR_FULL) return spec_dimen_size (ref->u.ar.as, dimen, result); if (ref->u.ar.type == AR_SECTION) { for (i = 0; dimen >= 0; i++) if (ref->u.ar.dimen_type[i] != DIMEN_ELEMENT) dimen--; return ref_dimen_size (&ref->u.ar, i - 1, result); } } if (array->shape && array->shape[dimen]) { mpz_init_set (*result, array->shape[dimen]); return SUCCESS; } if (spec_dimen_size (array->symtree->n.sym->as, dimen, result) == FAILURE) return FAILURE; break; case EXPR_ARRAY: if (array->shape == NULL) { /* Expressions with rank > 1 should have "shape" properly set */ if ( array->rank != 1 ) gfc_internal_error ("gfc_array_dimen_size(): Bad EXPR_ARRAY expr"); return gfc_array_size(array, result); } /* Fall through */ default: if (array->shape == NULL) return FAILURE; mpz_init_set (*result, array->shape[dimen]); break; } return SUCCESS; } /* Given an array expression, figure out how many elements are in the array. Returns SUCCESS if this is possible, and sets the 'result' variable. Otherwise returns FAILURE. */ try gfc_array_size (gfc_expr * array, mpz_t * result) { expand_info expand_save; gfc_ref *ref; int i, flag; try t; switch (array->expr_type) { case EXPR_ARRAY: flag = gfc_suppress_error; gfc_suppress_error = 1; expand_save = current_expand; current_expand.count = result; mpz_init_set_ui (*result, 0); current_expand.expand_work_function = count_elements; iter_stack = NULL; t = expand_constructor (array->value.constructor); gfc_suppress_error = flag; if (t == FAILURE) mpz_clear (*result); current_expand = expand_save; return t; case EXPR_VARIABLE: for (ref = array->ref; ref; ref = ref->next) { if (ref->type != REF_ARRAY) continue; if (ref->u.ar.type == AR_FULL) return spec_size (ref->u.ar.as, result); if (ref->u.ar.type == AR_SECTION) return ref_size (&ref->u.ar, result); } return spec_size (array->symtree->n.sym->as, result); default: if (array->rank == 0 || array->shape == NULL) return FAILURE; mpz_init_set_ui (*result, 1); for (i = 0; i < array->rank; i++) mpz_mul (*result, *result, array->shape[i]); break; } return SUCCESS; } /* Given an array reference, return the shape of the reference in an array of mpz_t integers. */ try gfc_array_ref_shape (gfc_array_ref * ar, mpz_t * shape) { int d; int i; d = 0; switch (ar->type) { case AR_FULL: for (; d < ar->as->rank; d++) if (spec_dimen_size (ar->as, d, &shape[d]) == FAILURE) goto cleanup; return SUCCESS; case AR_SECTION: for (i = 0; i < ar->dimen; i++) { if (ar->dimen_type[i] != DIMEN_ELEMENT) { if (ref_dimen_size (ar, i, &shape[d]) == FAILURE) goto cleanup; d++; } } return SUCCESS; default: break; } cleanup: for (d--; d >= 0; d--) mpz_clear (shape[d]); return FAILURE; } /* Given an array expression, find the array reference structure that characterizes the reference. */ gfc_array_ref * gfc_find_array_ref (gfc_expr * e) { gfc_ref *ref; for (ref = e->ref; ref; ref = ref->next) if (ref->type == REF_ARRAY && (ref->u.ar.type == AR_FULL || ref->u.ar.type == AR_SECTION)) break; if (ref == NULL) gfc_internal_error ("gfc_find_array_ref(): No ref found"); return &ref->u.ar; } /* Find out if an array shape is known at compile time. */ int gfc_is_compile_time_shape (gfc_array_spec *as) { int i; if (as->type != AS_EXPLICIT) return 0; for (i = 0; i < as->rank; i++) if (!gfc_is_constant_expr (as->lower[i]) || !gfc_is_constant_expr (as->upper[i])) return 0; return 1; }