1 /* Routines for manipulation of expression nodes.
2 Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software
4 Contributed by Andy Vaught
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
29 /* Get a new expr node. */
36 e = gfc_getmem (sizeof (gfc_expr));
38 gfc_clear_ts (&e->ts);
47 /* Free an argument list and everything below it. */
50 gfc_free_actual_arglist (gfc_actual_arglist * a1)
52 gfc_actual_arglist *a2;
57 gfc_free_expr (a1->expr);
64 /* Copy an arglist structure and all of the arguments. */
67 gfc_copy_actual_arglist (gfc_actual_arglist * p)
69 gfc_actual_arglist *head, *tail, *new;
73 for (; p; p = p->next)
75 new = gfc_get_actual_arglist ();
78 new->expr = gfc_copy_expr (p->expr);
93 /* Free a list of reference structures. */
96 gfc_free_ref_list (gfc_ref * p)
108 for (i = 0; i < GFC_MAX_DIMENSIONS; i++)
110 gfc_free_expr (p->u.ar.start[i]);
111 gfc_free_expr (p->u.ar.end[i]);
112 gfc_free_expr (p->u.ar.stride[i]);
118 gfc_free_expr (p->u.ss.start);
119 gfc_free_expr (p->u.ss.end);
131 /* Workhorse function for gfc_free_expr() that frees everything
132 beneath an expression node, but not the node itself. This is
133 useful when we want to simplify a node and replace it with
134 something else or the expression node belongs to another structure. */
137 free_expr0 (gfc_expr * e)
141 switch (e->expr_type)
146 gfc_free (e->value.character.string);
153 mpz_clear (e->value.integer);
157 mpfr_clear (e->value.real);
162 gfc_free (e->value.character.string);
166 mpfr_clear (e->value.complex.r);
167 mpfr_clear (e->value.complex.i);
177 if (e->value.op.op1 != NULL)
178 gfc_free_expr (e->value.op.op1);
179 if (e->value.op.op2 != NULL)
180 gfc_free_expr (e->value.op.op2);
184 gfc_free_actual_arglist (e->value.function.actual);
192 gfc_free_constructor (e->value.constructor);
196 gfc_free (e->value.character.string);
203 gfc_internal_error ("free_expr0(): Bad expr type");
206 /* Free a shape array. */
207 if (e->shape != NULL)
209 for (n = 0; n < e->rank; n++)
210 mpz_clear (e->shape[n]);
215 gfc_free_ref_list (e->ref);
217 memset (e, '\0', sizeof (gfc_expr));
221 /* Free an expression node and everything beneath it. */
224 gfc_free_expr (gfc_expr * e)
235 /* Graft the *src expression onto the *dest subexpression. */
238 gfc_replace_expr (gfc_expr * dest, gfc_expr * src)
248 /* Try to extract an integer constant from the passed expression node.
249 Returns an error message or NULL if the result is set. It is
250 tempting to generate an error and return SUCCESS or FAILURE, but
251 failure is OK for some callers. */
254 gfc_extract_int (gfc_expr * expr, int *result)
257 if (expr->expr_type != EXPR_CONSTANT)
258 return _("Constant expression required at %C");
260 if (expr->ts.type != BT_INTEGER)
261 return _("Integer expression required at %C");
263 if ((mpz_cmp_si (expr->value.integer, INT_MAX) > 0)
264 || (mpz_cmp_si (expr->value.integer, INT_MIN) < 0))
266 return _("Integer value too large in expression at %C");
269 *result = (int) mpz_get_si (expr->value.integer);
275 /* Recursively copy a list of reference structures. */
278 copy_ref (gfc_ref * src)
286 dest = gfc_get_ref ();
287 dest->type = src->type;
292 ar = gfc_copy_array_ref (&src->u.ar);
298 dest->u.c = src->u.c;
302 dest->u.ss = src->u.ss;
303 dest->u.ss.start = gfc_copy_expr (src->u.ss.start);
304 dest->u.ss.end = gfc_copy_expr (src->u.ss.end);
308 dest->next = copy_ref (src->next);
314 /* Detect whether an expression has any vector index array
318 gfc_has_vector_index (gfc_expr *e)
322 for (ref = e->ref; ref; ref = ref->next)
323 if (ref->type == REF_ARRAY)
324 for (i = 0; i < ref->u.ar.dimen; i++)
325 if (ref->u.ar.dimen_type[i] == DIMEN_VECTOR)
331 /* Copy a shape array. */
334 gfc_copy_shape (mpz_t * shape, int rank)
342 new_shape = gfc_get_shape (rank);
344 for (n = 0; n < rank; n++)
345 mpz_init_set (new_shape[n], shape[n]);
351 /* Copy a shape array excluding dimension N, where N is an integer
352 constant expression. Dimensions are numbered in fortran style --
355 So, if the original shape array contains R elements
356 { s1 ... sN-1 sN sN+1 ... sR-1 sR}
357 the result contains R-1 elements:
358 { s1 ... sN-1 sN+1 ... sR-1}
360 If anything goes wrong -- N is not a constant, its value is out
361 of range -- or anything else, just returns NULL.
365 gfc_copy_shape_excluding (mpz_t * shape, int rank, gfc_expr * dim)
367 mpz_t *new_shape, *s;
373 || dim->expr_type != EXPR_CONSTANT
374 || dim->ts.type != BT_INTEGER)
377 n = mpz_get_si (dim->value.integer);
378 n--; /* Convert to zero based index */
379 if (n < 0 || n >= rank)
382 s = new_shape = gfc_get_shape (rank-1);
384 for (i = 0; i < rank; i++)
388 mpz_init_set (*s, shape[i]);
395 /* Given an expression pointer, return a copy of the expression. This
396 subroutine is recursive. */
399 gfc_copy_expr (gfc_expr * p)
410 switch (q->expr_type)
413 s = gfc_getmem (p->value.character.length + 1);
414 q->value.character.string = s;
416 memcpy (s, p->value.character.string, p->value.character.length + 1);
422 s = gfc_getmem (p->value.character.length + 1);
423 q->value.character.string = s;
425 memcpy (s, p->value.character.string,
426 p->value.character.length + 1);
432 mpz_init_set (q->value.integer, p->value.integer);
436 gfc_set_model_kind (q->ts.kind);
437 mpfr_init (q->value.real);
438 mpfr_set (q->value.real, p->value.real, GFC_RND_MODE);
442 gfc_set_model_kind (q->ts.kind);
443 mpfr_init (q->value.complex.r);
444 mpfr_init (q->value.complex.i);
445 mpfr_set (q->value.complex.r, p->value.complex.r, GFC_RND_MODE);
446 mpfr_set (q->value.complex.i, p->value.complex.i, GFC_RND_MODE);
451 s = gfc_getmem (p->value.character.length + 1);
452 q->value.character.string = s;
454 memcpy (s, p->value.character.string,
455 p->value.character.length + 1);
460 break; /* Already done */
464 gfc_internal_error ("gfc_copy_expr(): Bad expr node");
471 switch (q->value.op.operator)
474 case INTRINSIC_UPLUS:
475 case INTRINSIC_UMINUS:
476 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
479 default: /* Binary operators */
480 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
481 q->value.op.op2 = gfc_copy_expr (p->value.op.op2);
488 q->value.function.actual =
489 gfc_copy_actual_arglist (p->value.function.actual);
494 q->value.constructor = gfc_copy_constructor (p->value.constructor);
502 q->shape = gfc_copy_shape (p->shape, p->rank);
504 q->ref = copy_ref (p->ref);
510 /* Return the maximum kind of two expressions. In general, higher
511 kind numbers mean more precision for numeric types. */
514 gfc_kind_max (gfc_expr * e1, gfc_expr * e2)
517 return (e1->ts.kind > e2->ts.kind) ? e1->ts.kind : e2->ts.kind;
521 /* Returns nonzero if the type is numeric, zero otherwise. */
524 numeric_type (bt type)
527 return type == BT_COMPLEX || type == BT_REAL || type == BT_INTEGER;
531 /* Returns nonzero if the typespec is a numeric type, zero otherwise. */
534 gfc_numeric_ts (gfc_typespec * ts)
537 return numeric_type (ts->type);
541 /* Returns an expression node that is an integer constant. */
550 p->expr_type = EXPR_CONSTANT;
551 p->ts.type = BT_INTEGER;
552 p->ts.kind = gfc_default_integer_kind;
554 p->where = gfc_current_locus;
555 mpz_init_set_si (p->value.integer, i);
561 /* Returns an expression node that is a logical constant. */
564 gfc_logical_expr (int i, locus * where)
570 p->expr_type = EXPR_CONSTANT;
571 p->ts.type = BT_LOGICAL;
572 p->ts.kind = gfc_default_logical_kind;
575 where = &gfc_current_locus;
577 p->value.logical = i;
583 /* Return an expression node with an optional argument list attached.
584 A variable number of gfc_expr pointers are strung together in an
585 argument list with a NULL pointer terminating the list. */
588 gfc_build_conversion (gfc_expr * e)
593 p->expr_type = EXPR_FUNCTION;
595 p->value.function.actual = NULL;
597 p->value.function.actual = gfc_get_actual_arglist ();
598 p->value.function.actual->expr = e;
604 /* Given an expression node with some sort of numeric binary
605 expression, insert type conversions required to make the operands
608 The exception is that the operands of an exponential don't have to
609 have the same type. If possible, the base is promoted to the type
610 of the exponent. For example, 1**2.3 becomes 1.0**2.3, but
611 1.0**2 stays as it is. */
614 gfc_type_convert_binary (gfc_expr * e)
618 op1 = e->value.op.op1;
619 op2 = e->value.op.op2;
621 if (op1->ts.type == BT_UNKNOWN || op2->ts.type == BT_UNKNOWN)
623 gfc_clear_ts (&e->ts);
627 /* Kind conversions of same type. */
628 if (op1->ts.type == op2->ts.type)
631 if (op1->ts.kind == op2->ts.kind)
633 /* No type conversions. */
638 if (op1->ts.kind > op2->ts.kind)
639 gfc_convert_type (op2, &op1->ts, 2);
641 gfc_convert_type (op1, &op2->ts, 2);
647 /* Integer combined with real or complex. */
648 if (op2->ts.type == BT_INTEGER)
652 /* Special case for ** operator. */
653 if (e->value.op.operator == INTRINSIC_POWER)
656 gfc_convert_type (e->value.op.op2, &e->ts, 2);
660 if (op1->ts.type == BT_INTEGER)
663 gfc_convert_type (e->value.op.op1, &e->ts, 2);
667 /* Real combined with complex. */
668 e->ts.type = BT_COMPLEX;
669 if (op1->ts.kind > op2->ts.kind)
670 e->ts.kind = op1->ts.kind;
672 e->ts.kind = op2->ts.kind;
673 if (op1->ts.type != BT_COMPLEX || op1->ts.kind != e->ts.kind)
674 gfc_convert_type (e->value.op.op1, &e->ts, 2);
675 if (op2->ts.type != BT_COMPLEX || op2->ts.kind != e->ts.kind)
676 gfc_convert_type (e->value.op.op2, &e->ts, 2);
683 /* Function to determine if an expression is constant or not. This
684 function expects that the expression has already been simplified. */
687 gfc_is_constant_expr (gfc_expr * e)
690 gfc_actual_arglist *arg;
696 switch (e->expr_type)
699 rv = (gfc_is_constant_expr (e->value.op.op1)
700 && (e->value.op.op2 == NULL
701 || gfc_is_constant_expr (e->value.op.op2)));
710 /* Call to intrinsic with at least one argument. */
712 if (e->value.function.isym && e->value.function.actual)
714 for (arg = e->value.function.actual; arg; arg = arg->next)
716 if (!gfc_is_constant_expr (arg->expr))
730 rv = (gfc_is_constant_expr (e->ref->u.ss.start)
731 && gfc_is_constant_expr (e->ref->u.ss.end));
736 for (c = e->value.constructor; c; c = c->next)
737 if (!gfc_is_constant_expr (c->expr))
745 rv = gfc_constant_ac (e);
749 gfc_internal_error ("gfc_is_constant_expr(): Unknown expression type");
756 /* Try to collapse intrinsic expressions. */
759 simplify_intrinsic_op (gfc_expr * p, int type)
761 gfc_expr *op1, *op2, *result;
763 if (p->value.op.operator == INTRINSIC_USER)
766 op1 = p->value.op.op1;
767 op2 = p->value.op.op2;
769 if (gfc_simplify_expr (op1, type) == FAILURE)
771 if (gfc_simplify_expr (op2, type) == FAILURE)
774 if (!gfc_is_constant_expr (op1)
775 || (op2 != NULL && !gfc_is_constant_expr (op2)))
779 p->value.op.op1 = NULL;
780 p->value.op.op2 = NULL;
782 switch (p->value.op.operator)
784 case INTRINSIC_UPLUS:
785 case INTRINSIC_PARENTHESES:
786 result = gfc_uplus (op1);
789 case INTRINSIC_UMINUS:
790 result = gfc_uminus (op1);
794 result = gfc_add (op1, op2);
797 case INTRINSIC_MINUS:
798 result = gfc_subtract (op1, op2);
801 case INTRINSIC_TIMES:
802 result = gfc_multiply (op1, op2);
805 case INTRINSIC_DIVIDE:
806 result = gfc_divide (op1, op2);
809 case INTRINSIC_POWER:
810 result = gfc_power (op1, op2);
813 case INTRINSIC_CONCAT:
814 result = gfc_concat (op1, op2);
818 result = gfc_eq (op1, op2);
822 result = gfc_ne (op1, op2);
826 result = gfc_gt (op1, op2);
830 result = gfc_ge (op1, op2);
834 result = gfc_lt (op1, op2);
838 result = gfc_le (op1, op2);
842 result = gfc_not (op1);
846 result = gfc_and (op1, op2);
850 result = gfc_or (op1, op2);
854 result = gfc_eqv (op1, op2);
858 result = gfc_neqv (op1, op2);
862 gfc_internal_error ("simplify_intrinsic_op(): Bad operator");
872 gfc_replace_expr (p, result);
878 /* Subroutine to simplify constructor expressions. Mutually recursive
879 with gfc_simplify_expr(). */
882 simplify_constructor (gfc_constructor * c, int type)
885 for (; c; c = c->next)
888 && (gfc_simplify_expr (c->iterator->start, type) == FAILURE
889 || gfc_simplify_expr (c->iterator->end, type) == FAILURE
890 || gfc_simplify_expr (c->iterator->step, type) == FAILURE))
893 if (c->expr && gfc_simplify_expr (c->expr, type) == FAILURE)
901 /* Pull a single array element out of an array constructor. */
903 static gfc_constructor *
904 find_array_element (gfc_constructor * cons, gfc_array_ref * ar)
906 unsigned long nelemen;
911 mpz_init_set_ui (offset, 0);
913 for (i = 0; i < ar->dimen; i++)
915 if (ar->start[i]->expr_type != EXPR_CONSTANT)
920 mpz_sub (delta, ar->start[i]->value.integer,
921 ar->as->lower[i]->value.integer);
922 mpz_add (offset, offset, delta);
927 if (mpz_fits_ulong_p (offset))
929 for (nelemen = mpz_get_ui (offset); nelemen > 0; nelemen--)
950 /* Find a component of a structure constructor. */
952 static gfc_constructor *
953 find_component_ref (gfc_constructor * cons, gfc_ref * ref)
958 comp = ref->u.c.sym->components;
959 pick = ref->u.c.component;
970 /* Replace an expression with the contents of a constructor, removing
971 the subobject reference in the process. */
974 remove_subobject_ref (gfc_expr * p, gfc_constructor * cons)
980 e->ref = p->ref->next;
982 gfc_replace_expr (p, e);
986 /* Simplify a subobject reference of a constructor. This occurs when
987 parameter variable values are substituted. */
990 simplify_const_ref (gfc_expr * p)
992 gfc_constructor *cons;
996 switch (p->ref->type)
999 switch (p->ref->u.ar.type)
1002 cons = find_array_element (p->value.constructor, &p->ref->u.ar);
1005 remove_subobject_ref (p, cons);
1009 if (p->ref->next != NULL)
1011 /* TODO: Simplify array subobject references. */
1014 gfc_free_ref_list (p->ref);
1019 /* TODO: Simplify array subsections. */
1026 cons = find_component_ref (p->value.constructor, p->ref);
1027 remove_subobject_ref (p, cons);
1031 /* TODO: Constant substrings. */
1040 /* Simplify a chain of references. */
1043 simplify_ref_chain (gfc_ref * ref, int type)
1047 for (; ref; ref = ref->next)
1052 for (n = 0; n < ref->u.ar.dimen; n++)
1054 if (gfc_simplify_expr (ref->u.ar.start[n], type)
1057 if (gfc_simplify_expr (ref->u.ar.end[n], type)
1060 if (gfc_simplify_expr (ref->u.ar.stride[n], type)
1067 if (gfc_simplify_expr (ref->u.ss.start, type) == FAILURE)
1069 if (gfc_simplify_expr (ref->u.ss.end, type) == FAILURE)
1081 /* Try to substitute the value of a parameter variable. */
1083 simplify_parameter_variable (gfc_expr * p, int type)
1088 e = gfc_copy_expr (p->symtree->n.sym->value);
1089 /* Do not copy subobject refs for constant. */
1090 if (e->expr_type != EXPR_CONSTANT && p->ref != NULL)
1091 e->ref = copy_ref (p->ref);
1092 t = gfc_simplify_expr (e, type);
1094 /* Only use the simplification if it eliminated all subobject
1096 if (t == SUCCESS && ! e->ref)
1097 gfc_replace_expr (p, e);
1104 /* Given an expression, simplify it by collapsing constant
1105 expressions. Most simplification takes place when the expression
1106 tree is being constructed. If an intrinsic function is simplified
1107 at some point, we get called again to collapse the result against
1110 We work by recursively simplifying expression nodes, simplifying
1111 intrinsic functions where possible, which can lead to further
1112 constant collapsing. If an operator has constant operand(s), we
1113 rip the expression apart, and rebuild it, hoping that it becomes
1116 The expression type is defined for:
1117 0 Basic expression parsing
1118 1 Simplifying array constructors -- will substitute
1120 Returns FAILURE on error, SUCCESS otherwise.
1121 NOTE: Will return SUCCESS even if the expression can not be simplified. */
1124 gfc_simplify_expr (gfc_expr * p, int type)
1126 gfc_actual_arglist *ap;
1131 switch (p->expr_type)
1138 for (ap = p->value.function.actual; ap; ap = ap->next)
1139 if (gfc_simplify_expr (ap->expr, type) == FAILURE)
1142 if (p->value.function.isym != NULL
1143 && gfc_intrinsic_func_interface (p, 1) == MATCH_ERROR)
1148 case EXPR_SUBSTRING:
1149 if (simplify_ref_chain (p->ref, type) == FAILURE)
1152 if (gfc_is_constant_expr (p))
1157 gfc_extract_int (p->ref->u.ss.start, &start);
1158 start--; /* Convert from one-based to zero-based. */
1159 gfc_extract_int (p->ref->u.ss.end, &end);
1160 s = gfc_getmem (end - start + 1);
1161 memcpy (s, p->value.character.string + start, end - start);
1162 s[end] = '\0'; /* TODO: C-style string for debugging. */
1163 gfc_free (p->value.character.string);
1164 p->value.character.string = s;
1165 p->value.character.length = end - start;
1166 p->ts.cl = gfc_get_charlen ();
1167 p->ts.cl->next = gfc_current_ns->cl_list;
1168 gfc_current_ns->cl_list = p->ts.cl;
1169 p->ts.cl->length = gfc_int_expr (p->value.character.length);
1170 gfc_free_ref_list (p->ref);
1172 p->expr_type = EXPR_CONSTANT;
1177 if (simplify_intrinsic_op (p, type) == FAILURE)
1182 /* Only substitute array parameter variables if we are in an
1183 initialization expression, or we want a subsection. */
1184 if (p->symtree->n.sym->attr.flavor == FL_PARAMETER
1185 && (gfc_init_expr || p->ref
1186 || p->symtree->n.sym->value->expr_type != EXPR_ARRAY))
1188 if (simplify_parameter_variable (p, type) == FAILURE)
1195 gfc_simplify_iterator_var (p);
1198 /* Simplify subcomponent references. */
1199 if (simplify_ref_chain (p->ref, type) == FAILURE)
1204 case EXPR_STRUCTURE:
1206 if (simplify_ref_chain (p->ref, type) == FAILURE)
1209 if (simplify_constructor (p->value.constructor, type) == FAILURE)
1212 if (p->expr_type == EXPR_ARRAY)
1213 gfc_expand_constructor (p);
1215 if (simplify_const_ref (p) == FAILURE)
1225 /* Returns the type of an expression with the exception that iterator
1226 variables are automatically integers no matter what else they may
1233 if (e->expr_type == EXPR_VARIABLE && gfc_check_iter_variable (e) == SUCCESS)
1240 /* Check an intrinsic arithmetic operation to see if it is consistent
1241 with some type of expression. */
1243 static try check_init_expr (gfc_expr *);
1246 check_intrinsic_op (gfc_expr * e, try (*check_function) (gfc_expr *))
1248 gfc_expr *op1 = e->value.op.op1;
1249 gfc_expr *op2 = e->value.op.op2;
1251 if ((*check_function) (op1) == FAILURE)
1254 switch (e->value.op.operator)
1256 case INTRINSIC_UPLUS:
1257 case INTRINSIC_UMINUS:
1258 if (!numeric_type (et0 (op1)))
1268 if ((*check_function) (op2) == FAILURE)
1271 if (!(et0 (op1) == BT_CHARACTER && et0 (op2) == BT_CHARACTER)
1272 && !(numeric_type (et0 (op1)) && numeric_type (et0 (op2))))
1274 gfc_error ("Numeric or CHARACTER operands are required in "
1275 "expression at %L", &e->where);
1280 case INTRINSIC_PLUS:
1281 case INTRINSIC_MINUS:
1282 case INTRINSIC_TIMES:
1283 case INTRINSIC_DIVIDE:
1284 case INTRINSIC_POWER:
1285 if ((*check_function) (op2) == FAILURE)
1288 if (!numeric_type (et0 (op1)) || !numeric_type (et0 (op2)))
1291 if (e->value.op.operator == INTRINSIC_POWER
1292 && check_function == check_init_expr && et0 (op2) != BT_INTEGER)
1294 gfc_error ("Exponent at %L must be INTEGER for an initialization "
1295 "expression", &op2->where);
1301 case INTRINSIC_CONCAT:
1302 if ((*check_function) (op2) == FAILURE)
1305 if (et0 (op1) != BT_CHARACTER || et0 (op2) != BT_CHARACTER)
1307 gfc_error ("Concatenation operator in expression at %L "
1308 "must have two CHARACTER operands", &op1->where);
1312 if (op1->ts.kind != op2->ts.kind)
1314 gfc_error ("Concat operator at %L must concatenate strings of the "
1315 "same kind", &e->where);
1322 if (et0 (op1) != BT_LOGICAL)
1324 gfc_error (".NOT. operator in expression at %L must have a LOGICAL "
1325 "operand", &op1->where);
1334 case INTRINSIC_NEQV:
1335 if ((*check_function) (op2) == FAILURE)
1338 if (et0 (op1) != BT_LOGICAL || et0 (op2) != BT_LOGICAL)
1340 gfc_error ("LOGICAL operands are required in expression at %L",
1348 gfc_error ("Only intrinsic operators can be used in expression at %L",
1356 gfc_error ("Numeric operands are required in expression at %L", &e->where);
1363 /* Certain inquiry functions are specifically allowed to have variable
1364 arguments, which is an exception to the normal requirement that an
1365 initialization function have initialization arguments. We head off
1366 this problem here. */
1369 check_inquiry (gfc_expr * e, int not_restricted)
1373 /* FIXME: This should be moved into the intrinsic definitions,
1374 to eliminate this ugly hack. */
1375 static const char * const inquiry_function[] = {
1376 "digits", "epsilon", "huge", "kind", "len", "maxexponent", "minexponent",
1377 "precision", "radix", "range", "tiny", "bit_size", "size", "shape",
1378 "lbound", "ubound", NULL
1383 /* An undeclared parameter will get us here (PR25018). */
1384 if (e->symtree == NULL)
1387 name = e->symtree->n.sym->name;
1389 for (i = 0; inquiry_function[i]; i++)
1390 if (strcmp (inquiry_function[i], name) == 0)
1393 if (inquiry_function[i] == NULL)
1396 e = e->value.function.actual->expr;
1398 if (e == NULL || e->expr_type != EXPR_VARIABLE)
1401 /* At this point we have an inquiry function with a variable argument. The
1402 type of the variable might be undefined, but we need it now, because the
1403 arguments of these functions are allowed to be undefined. */
1405 if (e->ts.type == BT_UNKNOWN)
1407 if (e->symtree->n.sym->ts.type == BT_UNKNOWN
1408 && gfc_set_default_type (e->symtree->n.sym, 0, gfc_current_ns)
1412 e->ts = e->symtree->n.sym->ts;
1415 /* Assumed character length will not reduce to a constant expression
1416 with LEN, as required by the standard. */
1417 if (i == 4 && not_restricted
1418 && e->symtree->n.sym->ts.type == BT_CHARACTER
1419 && e->symtree->n.sym->ts.cl->length == NULL)
1420 gfc_notify_std (GFC_STD_GNU, "assumed character length "
1421 "variable '%s' in constant expression at %L",
1422 e->symtree->n.sym->name, &e->where);
1428 /* Verify that an expression is an initialization expression. A side
1429 effect is that the expression tree is reduced to a single constant
1430 node if all goes well. This would normally happen when the
1431 expression is constructed but function references are assumed to be
1432 intrinsics in the context of initialization expressions. If
1433 FAILURE is returned an error message has been generated. */
1436 check_init_expr (gfc_expr * e)
1438 gfc_actual_arglist *ap;
1445 switch (e->expr_type)
1448 t = check_intrinsic_op (e, check_init_expr);
1450 t = gfc_simplify_expr (e, 0);
1457 if (check_inquiry (e, 1) != SUCCESS)
1460 for (ap = e->value.function.actual; ap; ap = ap->next)
1461 if (check_init_expr (ap->expr) == FAILURE)
1470 m = gfc_intrinsic_func_interface (e, 0);
1473 gfc_error ("Function '%s' in initialization expression at %L "
1474 "must be an intrinsic function",
1475 e->symtree->n.sym->name, &e->where);
1486 if (gfc_check_iter_variable (e) == SUCCESS)
1489 if (e->symtree->n.sym->attr.flavor == FL_PARAMETER)
1491 t = simplify_parameter_variable (e, 0);
1495 gfc_error ("Parameter '%s' at %L has not been declared or is "
1496 "a variable, which does not reduce to a constant "
1497 "expression", e->symtree->n.sym->name, &e->where);
1506 case EXPR_SUBSTRING:
1507 t = check_init_expr (e->ref->u.ss.start);
1511 t = check_init_expr (e->ref->u.ss.end);
1513 t = gfc_simplify_expr (e, 0);
1517 case EXPR_STRUCTURE:
1518 t = gfc_check_constructor (e, check_init_expr);
1522 t = gfc_check_constructor (e, check_init_expr);
1526 t = gfc_expand_constructor (e);
1530 t = gfc_check_constructor_type (e);
1534 gfc_internal_error ("check_init_expr(): Unknown expression type");
1541 /* Match an initialization expression. We work by first matching an
1542 expression, then reducing it to a constant. */
1545 gfc_match_init_expr (gfc_expr ** result)
1551 m = gfc_match_expr (&expr);
1556 t = gfc_resolve_expr (expr);
1558 t = check_init_expr (expr);
1563 gfc_free_expr (expr);
1567 if (expr->expr_type == EXPR_ARRAY
1568 && (gfc_check_constructor_type (expr) == FAILURE
1569 || gfc_expand_constructor (expr) == FAILURE))
1571 gfc_free_expr (expr);
1575 /* Not all inquiry functions are simplified to constant expressions
1576 so it is necessary to call check_inquiry again. */
1577 if (!gfc_is_constant_expr (expr)
1578 && check_inquiry (expr, 1) == FAILURE)
1580 gfc_error ("Initialization expression didn't reduce %C");
1591 static try check_restricted (gfc_expr *);
1593 /* Given an actual argument list, test to see that each argument is a
1594 restricted expression and optionally if the expression type is
1595 integer or character. */
1598 restricted_args (gfc_actual_arglist * a)
1600 for (; a; a = a->next)
1602 if (check_restricted (a->expr) == FAILURE)
1610 /************* Restricted/specification expressions *************/
1613 /* Make sure a non-intrinsic function is a specification function. */
1616 external_spec_function (gfc_expr * e)
1620 f = e->value.function.esym;
1622 if (f->attr.proc == PROC_ST_FUNCTION)
1624 gfc_error ("Specification function '%s' at %L cannot be a statement "
1625 "function", f->name, &e->where);
1629 if (f->attr.proc == PROC_INTERNAL)
1631 gfc_error ("Specification function '%s' at %L cannot be an internal "
1632 "function", f->name, &e->where);
1638 gfc_error ("Specification function '%s' at %L must be PURE", f->name,
1643 if (f->attr.recursive)
1645 gfc_error ("Specification function '%s' at %L cannot be RECURSIVE",
1646 f->name, &e->where);
1650 return restricted_args (e->value.function.actual);
1654 /* Check to see that a function reference to an intrinsic is a
1655 restricted expression. */
1658 restricted_intrinsic (gfc_expr * e)
1660 /* TODO: Check constraints on inquiry functions. 7.1.6.2 (7). */
1661 if (check_inquiry (e, 0) == SUCCESS)
1664 return restricted_args (e->value.function.actual);
1668 /* Verify that an expression is a restricted expression. Like its
1669 cousin check_init_expr(), an error message is generated if we
1673 check_restricted (gfc_expr * e)
1681 switch (e->expr_type)
1684 t = check_intrinsic_op (e, check_restricted);
1686 t = gfc_simplify_expr (e, 0);
1691 t = e->value.function.esym ?
1692 external_spec_function (e) : restricted_intrinsic (e);
1697 sym = e->symtree->n.sym;
1700 if (sym->attr.optional)
1702 gfc_error ("Dummy argument '%s' at %L cannot be OPTIONAL",
1703 sym->name, &e->where);
1707 if (sym->attr.intent == INTENT_OUT)
1709 gfc_error ("Dummy argument '%s' at %L cannot be INTENT(OUT)",
1710 sym->name, &e->where);
1714 /* gfc_is_formal_arg broadcasts that a formal argument list is being processed
1715 in resolve.c(resolve_formal_arglist). This is done so that host associated
1716 dummy array indices are accepted (PR23446). */
1717 if (sym->attr.in_common
1718 || sym->attr.use_assoc
1720 || sym->ns != gfc_current_ns
1721 || (sym->ns->proc_name != NULL
1722 && sym->ns->proc_name->attr.flavor == FL_MODULE)
1723 || gfc_is_formal_arg ())
1729 gfc_error ("Variable '%s' cannot appear in the expression at %L",
1730 sym->name, &e->where);
1739 case EXPR_SUBSTRING:
1740 t = gfc_specification_expr (e->ref->u.ss.start);
1744 t = gfc_specification_expr (e->ref->u.ss.end);
1746 t = gfc_simplify_expr (e, 0);
1750 case EXPR_STRUCTURE:
1751 t = gfc_check_constructor (e, check_restricted);
1755 t = gfc_check_constructor (e, check_restricted);
1759 gfc_internal_error ("check_restricted(): Unknown expression type");
1766 /* Check to see that an expression is a specification expression. If
1767 we return FAILURE, an error has been generated. */
1770 gfc_specification_expr (gfc_expr * e)
1775 if (e->ts.type != BT_INTEGER)
1777 gfc_error ("Expression at %L must be of INTEGER type", &e->where);
1783 gfc_error ("Expression at %L must be scalar", &e->where);
1787 if (gfc_simplify_expr (e, 0) == FAILURE)
1790 return check_restricted (e);
1794 /************** Expression conformance checks. *************/
1796 /* Given two expressions, make sure that the arrays are conformable. */
1799 gfc_check_conformance (const char *optype_msgid,
1800 gfc_expr * op1, gfc_expr * op2)
1802 int op1_flag, op2_flag, d;
1803 mpz_t op1_size, op2_size;
1806 if (op1->rank == 0 || op2->rank == 0)
1809 if (op1->rank != op2->rank)
1811 gfc_error ("Incompatible ranks in %s at %L", _(optype_msgid),
1818 for (d = 0; d < op1->rank; d++)
1820 op1_flag = gfc_array_dimen_size (op1, d, &op1_size) == SUCCESS;
1821 op2_flag = gfc_array_dimen_size (op2, d, &op2_size) == SUCCESS;
1823 if (op1_flag && op2_flag && mpz_cmp (op1_size, op2_size) != 0)
1825 gfc_error ("different shape for %s at %L on dimension %d (%d/%d)",
1826 _(optype_msgid), &op1->where, d + 1,
1827 (int) mpz_get_si (op1_size),
1828 (int) mpz_get_si (op2_size));
1834 mpz_clear (op1_size);
1836 mpz_clear (op2_size);
1846 /* Given an assignable expression and an arbitrary expression, make
1847 sure that the assignment can take place. */
1850 gfc_check_assign (gfc_expr * lvalue, gfc_expr * rvalue, int conform)
1854 sym = lvalue->symtree->n.sym;
1856 if (sym->attr.intent == INTENT_IN)
1858 gfc_error ("Can't assign to INTENT(IN) variable '%s' at %L",
1859 sym->name, &lvalue->where);
1863 if (sym->attr.flavor == FL_PROCEDURE && sym->attr.use_assoc)
1865 gfc_error ("'%s' in the assignment at %L cannot be an l-value "
1866 "since it is a procedure", sym->name, &lvalue->where);
1871 if (rvalue->rank != 0 && lvalue->rank != rvalue->rank)
1873 gfc_error ("Incompatible ranks %d and %d in assignment at %L",
1874 lvalue->rank, rvalue->rank, &lvalue->where);
1878 if (lvalue->ts.type == BT_UNKNOWN)
1880 gfc_error ("Variable type is UNKNOWN in assignment at %L",
1885 if (rvalue->expr_type == EXPR_NULL)
1887 gfc_error ("NULL appears on right-hand side in assignment at %L",
1892 if (sym->attr.cray_pointee
1893 && lvalue->ref != NULL
1894 && lvalue->ref->u.ar.type != AR_ELEMENT
1895 && lvalue->ref->u.ar.as->cp_was_assumed)
1897 gfc_error ("Vector assignment to assumed-size Cray Pointee at %L"
1898 " is illegal.", &lvalue->where);
1902 /* This is possibly a typo: x = f() instead of x => f() */
1903 if (gfc_option.warn_surprising
1904 && rvalue->expr_type == EXPR_FUNCTION
1905 && rvalue->symtree->n.sym->attr.pointer)
1906 gfc_warning ("POINTER valued function appears on right-hand side of "
1907 "assignment at %L", &rvalue->where);
1909 /* Check size of array assignments. */
1910 if (lvalue->rank != 0 && rvalue->rank != 0
1911 && gfc_check_conformance ("Array assignment", lvalue, rvalue) != SUCCESS)
1914 if (gfc_compare_types (&lvalue->ts, &rvalue->ts))
1919 /* Numeric can be converted to any other numeric. And Hollerith can be
1920 converted to any other type. */
1921 if ((gfc_numeric_ts (&lvalue->ts) && gfc_numeric_ts (&rvalue->ts))
1922 || rvalue->ts.type == BT_HOLLERITH)
1925 if (lvalue->ts.type == BT_LOGICAL && rvalue->ts.type == BT_LOGICAL)
1928 gfc_error ("Incompatible types in assignment at %L, %s to %s",
1929 &rvalue->where, gfc_typename (&rvalue->ts),
1930 gfc_typename (&lvalue->ts));
1935 return gfc_convert_type (rvalue, &lvalue->ts, 1);
1939 /* Check that a pointer assignment is OK. We first check lvalue, and
1940 we only check rvalue if it's not an assignment to NULL() or a
1941 NULLIFY statement. */
1944 gfc_check_pointer_assign (gfc_expr * lvalue, gfc_expr * rvalue)
1946 symbol_attribute attr;
1949 if (lvalue->symtree->n.sym->ts.type == BT_UNKNOWN)
1951 gfc_error ("Pointer assignment target is not a POINTER at %L",
1956 if (lvalue->symtree->n.sym->attr.flavor == FL_PROCEDURE
1957 && lvalue->symtree->n.sym->attr.use_assoc)
1959 gfc_error ("'%s' in the pointer assignment at %L cannot be an "
1960 "l-value since it is a procedure",
1961 lvalue->symtree->n.sym->name, &lvalue->where);
1965 attr = gfc_variable_attr (lvalue, NULL);
1968 gfc_error ("Pointer assignment to non-POINTER at %L", &lvalue->where);
1972 is_pure = gfc_pure (NULL);
1974 if (is_pure && gfc_impure_variable (lvalue->symtree->n.sym))
1976 gfc_error ("Bad pointer object in PURE procedure at %L",
1981 /* If rvalue is a NULL() or NULLIFY, we're done. Otherwise the type,
1982 kind, etc for lvalue and rvalue must match, and rvalue must be a
1983 pure variable if we're in a pure function. */
1984 if (rvalue->expr_type == EXPR_NULL)
1987 if (!gfc_compare_types (&lvalue->ts, &rvalue->ts))
1989 gfc_error ("Different types in pointer assignment at %L",
1994 if (lvalue->ts.kind != rvalue->ts.kind)
1996 gfc_error ("Different kind type parameters in pointer "
1997 "assignment at %L", &lvalue->where);
2001 if (lvalue->ts.type == BT_CHARACTER
2002 && lvalue->ts.cl->length && rvalue->ts.cl->length
2003 && abs (gfc_dep_compare_expr (lvalue->ts.cl->length,
2004 rvalue->ts.cl->length)) == 1)
2006 gfc_error ("Different character lengths in pointer "
2007 "assignment at %L", &lvalue->where);
2011 attr = gfc_expr_attr (rvalue);
2012 if (!attr.target && !attr.pointer)
2014 gfc_error ("Pointer assignment target is neither TARGET "
2015 "nor POINTER at %L", &rvalue->where);
2019 if (is_pure && gfc_impure_variable (rvalue->symtree->n.sym))
2021 gfc_error ("Bad target in pointer assignment in PURE "
2022 "procedure at %L", &rvalue->where);
2025 if (lvalue->rank != rvalue->rank)
2027 gfc_error ("Unequal ranks %d and %d in pointer assignment at %L",
2028 lvalue->rank, rvalue->rank, &rvalue->where);
2032 if (gfc_has_vector_index (rvalue))
2034 gfc_error ("Pointer assignment with vector subscript "
2035 "on rhs at %L", &rvalue->where);
2043 /* Relative of gfc_check_assign() except that the lvalue is a single
2044 symbol. Used for initialization assignments. */
2047 gfc_check_assign_symbol (gfc_symbol * sym, gfc_expr * rvalue)
2052 memset (&lvalue, '\0', sizeof (gfc_expr));
2054 lvalue.expr_type = EXPR_VARIABLE;
2055 lvalue.ts = sym->ts;
2057 lvalue.rank = sym->as->rank;
2058 lvalue.symtree = (gfc_symtree *)gfc_getmem (sizeof (gfc_symtree));
2059 lvalue.symtree->n.sym = sym;
2060 lvalue.where = sym->declared_at;
2062 if (sym->attr.pointer)
2063 r = gfc_check_pointer_assign (&lvalue, rvalue);
2065 r = gfc_check_assign (&lvalue, rvalue, 1);
2067 gfc_free (lvalue.symtree);
2073 /* Get an expression for a default initializer. */
2076 gfc_default_initializer (gfc_typespec *ts)
2078 gfc_constructor *tail;
2084 /* See if we have a default initializer. */
2085 for (c = ts->derived->components; c; c = c->next)
2087 if (c->initializer && init == NULL)
2088 init = gfc_get_expr ();
2094 /* Build the constructor. */
2095 init->expr_type = EXPR_STRUCTURE;
2097 init->where = ts->derived->declared_at;
2099 for (c = ts->derived->components; c; c = c->next)
2102 init->value.constructor = tail = gfc_get_constructor ();
2105 tail->next = gfc_get_constructor ();
2110 tail->expr = gfc_copy_expr (c->initializer);
2116 /* Given a symbol, create an expression node with that symbol as a
2117 variable. If the symbol is array valued, setup a reference of the
2121 gfc_get_variable_expr (gfc_symtree * var)
2125 e = gfc_get_expr ();
2126 e->expr_type = EXPR_VARIABLE;
2128 e->ts = var->n.sym->ts;
2130 if (var->n.sym->as != NULL)
2132 e->rank = var->n.sym->as->rank;
2133 e->ref = gfc_get_ref ();
2134 e->ref->type = REF_ARRAY;
2135 e->ref->u.ar.type = AR_FULL;
2142 /* Traverse expr, marking all EXPR_VARIABLE symbols referenced. */
2145 gfc_expr_set_symbols_referenced (gfc_expr * expr)
2147 gfc_actual_arglist *arg;
2154 switch (expr->expr_type)
2157 gfc_expr_set_symbols_referenced (expr->value.op.op1);
2158 gfc_expr_set_symbols_referenced (expr->value.op.op2);
2162 for (arg = expr->value.function.actual; arg; arg = arg->next)
2163 gfc_expr_set_symbols_referenced (arg->expr);
2167 gfc_set_sym_referenced (expr->symtree->n.sym);
2172 case EXPR_SUBSTRING:
2175 case EXPR_STRUCTURE:
2177 for (c = expr->value.constructor; c; c = c->next)
2178 gfc_expr_set_symbols_referenced (c->expr);
2186 for (ref = expr->ref; ref; ref = ref->next)
2190 for (i = 0; i < ref->u.ar.dimen; i++)
2192 gfc_expr_set_symbols_referenced (ref->u.ar.start[i]);
2193 gfc_expr_set_symbols_referenced (ref->u.ar.end[i]);
2194 gfc_expr_set_symbols_referenced (ref->u.ar.stride[i]);
2202 gfc_expr_set_symbols_referenced (ref->u.ss.start);
2203 gfc_expr_set_symbols_referenced (ref->u.ss.end);