1 /* Routines for manipulation of expression nodes.
2 Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
3 Free Software Foundation, Inc.
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 3, 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 COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
28 /* Get a new expr node. */
35 e = gfc_getmem (sizeof (gfc_expr));
36 gfc_clear_ts (&e->ts);
40 e->con_by_offset = NULL;
45 /* Free an argument list and everything below it. */
48 gfc_free_actual_arglist (gfc_actual_arglist *a1)
50 gfc_actual_arglist *a2;
55 gfc_free_expr (a1->expr);
62 /* Copy an arglist structure and all of the arguments. */
65 gfc_copy_actual_arglist (gfc_actual_arglist *p)
67 gfc_actual_arglist *head, *tail, *new;
71 for (; p; p = p->next)
73 new = gfc_get_actual_arglist ();
76 new->expr = gfc_copy_expr (p->expr);
91 /* Free a list of reference structures. */
94 gfc_free_ref_list (gfc_ref *p)
106 for (i = 0; i < GFC_MAX_DIMENSIONS; i++)
108 gfc_free_expr (p->u.ar.start[i]);
109 gfc_free_expr (p->u.ar.end[i]);
110 gfc_free_expr (p->u.ar.stride[i]);
116 gfc_free_expr (p->u.ss.start);
117 gfc_free_expr (p->u.ss.end);
129 /* Workhorse function for gfc_free_expr() that frees everything
130 beneath an expression node, but not the node itself. This is
131 useful when we want to simplify a node and replace it with
132 something else or the expression node belongs to another structure. */
135 free_expr0 (gfc_expr *e)
139 switch (e->expr_type)
142 /* Free any parts of the value that need freeing. */
146 mpz_clear (e->value.integer);
150 mpfr_clear (e->value.real);
154 gfc_free (e->value.character.string);
158 mpfr_clear (e->value.complex.r);
159 mpfr_clear (e->value.complex.i);
166 /* Free the representation, except in character constants where it
167 is the same as value.character.string and thus already freed. */
168 if (e->representation.string && e->ts.type != BT_CHARACTER)
169 gfc_free (e->representation.string);
174 if (e->value.op.op1 != NULL)
175 gfc_free_expr (e->value.op.op1);
176 if (e->value.op.op2 != NULL)
177 gfc_free_expr (e->value.op.op2);
181 gfc_free_actual_arglist (e->value.function.actual);
189 gfc_free_constructor (e->value.constructor);
193 gfc_free (e->value.character.string);
200 gfc_internal_error ("free_expr0(): Bad expr type");
203 /* Free a shape array. */
204 if (e->shape != NULL)
206 for (n = 0; n < e->rank; n++)
207 mpz_clear (e->shape[n]);
212 gfc_free_ref_list (e->ref);
214 memset (e, '\0', sizeof (gfc_expr));
218 /* Free an expression node and everything beneath it. */
221 gfc_free_expr (gfc_expr *e)
225 if (e->con_by_offset)
226 splay_tree_delete (e->con_by_offset);
232 /* Graft the *src expression onto the *dest subexpression. */
235 gfc_replace_expr (gfc_expr *dest, gfc_expr *src)
243 /* Try to extract an integer constant from the passed expression node.
244 Returns an error message or NULL if the result is set. It is
245 tempting to generate an error and return SUCCESS or FAILURE, but
246 failure is OK for some callers. */
249 gfc_extract_int (gfc_expr *expr, int *result)
251 if (expr->expr_type != EXPR_CONSTANT)
252 return _("Constant expression required at %C");
254 if (expr->ts.type != BT_INTEGER)
255 return _("Integer expression required at %C");
257 if ((mpz_cmp_si (expr->value.integer, INT_MAX) > 0)
258 || (mpz_cmp_si (expr->value.integer, INT_MIN) < 0))
260 return _("Integer value too large in expression at %C");
263 *result = (int) mpz_get_si (expr->value.integer);
269 /* Recursively copy a list of reference structures. */
272 copy_ref (gfc_ref *src)
280 dest = gfc_get_ref ();
281 dest->type = src->type;
286 ar = gfc_copy_array_ref (&src->u.ar);
292 dest->u.c = src->u.c;
296 dest->u.ss = src->u.ss;
297 dest->u.ss.start = gfc_copy_expr (src->u.ss.start);
298 dest->u.ss.end = gfc_copy_expr (src->u.ss.end);
302 dest->next = copy_ref (src->next);
308 /* Detect whether an expression has any vector index array references. */
311 gfc_has_vector_index (gfc_expr *e)
315 for (ref = e->ref; ref; ref = ref->next)
316 if (ref->type == REF_ARRAY)
317 for (i = 0; i < ref->u.ar.dimen; i++)
318 if (ref->u.ar.dimen_type[i] == DIMEN_VECTOR)
324 /* Copy a shape array. */
327 gfc_copy_shape (mpz_t *shape, int rank)
335 new_shape = gfc_get_shape (rank);
337 for (n = 0; n < rank; n++)
338 mpz_init_set (new_shape[n], shape[n]);
344 /* Copy a shape array excluding dimension N, where N is an integer
345 constant expression. Dimensions are numbered in fortran style --
348 So, if the original shape array contains R elements
349 { s1 ... sN-1 sN sN+1 ... sR-1 sR}
350 the result contains R-1 elements:
351 { s1 ... sN-1 sN+1 ... sR-1}
353 If anything goes wrong -- N is not a constant, its value is out
354 of range -- or anything else, just returns NULL. */
357 gfc_copy_shape_excluding (mpz_t *shape, int rank, gfc_expr *dim)
359 mpz_t *new_shape, *s;
365 || dim->expr_type != EXPR_CONSTANT
366 || dim->ts.type != BT_INTEGER)
369 n = mpz_get_si (dim->value.integer);
370 n--; /* Convert to zero based index. */
371 if (n < 0 || n >= rank)
374 s = new_shape = gfc_get_shape (rank - 1);
376 for (i = 0; i < rank; i++)
380 mpz_init_set (*s, shape[i]);
388 /* Given an expression pointer, return a copy of the expression. This
389 subroutine is recursive. */
392 gfc_copy_expr (gfc_expr *p)
403 switch (q->expr_type)
406 s = gfc_getmem (p->value.character.length + 1);
407 q->value.character.string = s;
409 memcpy (s, p->value.character.string, p->value.character.length + 1);
413 /* Copy target representation, if it exists. */
414 if (p->representation.string)
416 s = gfc_getmem (p->representation.length + 1);
417 q->representation.string = s;
419 memcpy (s, p->representation.string, p->representation.length + 1);
422 /* Copy the values of any pointer components of p->value. */
426 mpz_init_set (q->value.integer, p->value.integer);
430 gfc_set_model_kind (q->ts.kind);
431 mpfr_init (q->value.real);
432 mpfr_set (q->value.real, p->value.real, GFC_RND_MODE);
436 gfc_set_model_kind (q->ts.kind);
437 mpfr_init (q->value.complex.r);
438 mpfr_init (q->value.complex.i);
439 mpfr_set (q->value.complex.r, p->value.complex.r, GFC_RND_MODE);
440 mpfr_set (q->value.complex.i, p->value.complex.i, GFC_RND_MODE);
444 if (p->representation.string)
445 q->value.character.string = q->representation.string;
448 s = gfc_getmem (p->value.character.length + 1);
449 q->value.character.string = s;
451 /* This is the case for the C_NULL_CHAR named constant. */
452 if (p->value.character.length == 0
453 && (p->ts.is_c_interop || p->ts.is_iso_c))
456 /* Need to set the length to 1 to make sure the NUL
457 terminator is copied. */
458 q->value.character.length = 1;
461 memcpy (s, p->value.character.string,
462 p->value.character.length + 1);
469 break; /* Already done. */
473 /* Should never be reached. */
475 gfc_internal_error ("gfc_copy_expr(): Bad expr node");
482 switch (q->value.op.operator)
485 case INTRINSIC_PARENTHESES:
486 case INTRINSIC_UPLUS:
487 case INTRINSIC_UMINUS:
488 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
491 default: /* Binary operators. */
492 q->value.op.op1 = gfc_copy_expr (p->value.op.op1);
493 q->value.op.op2 = gfc_copy_expr (p->value.op.op2);
500 q->value.function.actual =
501 gfc_copy_actual_arglist (p->value.function.actual);
506 q->value.constructor = gfc_copy_constructor (p->value.constructor);
514 q->shape = gfc_copy_shape (p->shape, p->rank);
516 q->ref = copy_ref (p->ref);
522 /* Return the maximum kind of two expressions. In general, higher
523 kind numbers mean more precision for numeric types. */
526 gfc_kind_max (gfc_expr *e1, gfc_expr *e2)
528 return (e1->ts.kind > e2->ts.kind) ? e1->ts.kind : e2->ts.kind;
532 /* Returns nonzero if the type is numeric, zero otherwise. */
535 numeric_type (bt type)
537 return type == BT_COMPLEX || type == BT_REAL || type == BT_INTEGER;
541 /* Returns nonzero if the typespec is a numeric type, zero otherwise. */
544 gfc_numeric_ts (gfc_typespec *ts)
546 return numeric_type (ts->type);
550 /* Returns an expression node that is an integer constant. */
559 p->expr_type = EXPR_CONSTANT;
560 p->ts.type = BT_INTEGER;
561 p->ts.kind = gfc_default_integer_kind;
563 p->where = gfc_current_locus;
564 mpz_init_set_si (p->value.integer, i);
570 /* Returns an expression node that is a logical constant. */
573 gfc_logical_expr (int i, locus *where)
579 p->expr_type = EXPR_CONSTANT;
580 p->ts.type = BT_LOGICAL;
581 p->ts.kind = gfc_default_logical_kind;
584 where = &gfc_current_locus;
586 p->value.logical = i;
592 /* Return an expression node with an optional argument list attached.
593 A variable number of gfc_expr pointers are strung together in an
594 argument list with a NULL pointer terminating the list. */
597 gfc_build_conversion (gfc_expr *e)
602 p->expr_type = EXPR_FUNCTION;
604 p->value.function.actual = NULL;
606 p->value.function.actual = gfc_get_actual_arglist ();
607 p->value.function.actual->expr = e;
613 /* Given an expression node with some sort of numeric binary
614 expression, insert type conversions required to make the operands
617 The exception is that the operands of an exponential don't have to
618 have the same type. If possible, the base is promoted to the type
619 of the exponent. For example, 1**2.3 becomes 1.0**2.3, but
620 1.0**2 stays as it is. */
623 gfc_type_convert_binary (gfc_expr *e)
627 op1 = e->value.op.op1;
628 op2 = e->value.op.op2;
630 if (op1->ts.type == BT_UNKNOWN || op2->ts.type == BT_UNKNOWN)
632 gfc_clear_ts (&e->ts);
636 /* Kind conversions of same type. */
637 if (op1->ts.type == op2->ts.type)
639 if (op1->ts.kind == op2->ts.kind)
641 /* No type conversions. */
646 if (op1->ts.kind > op2->ts.kind)
647 gfc_convert_type (op2, &op1->ts, 2);
649 gfc_convert_type (op1, &op2->ts, 2);
655 /* Integer combined with real or complex. */
656 if (op2->ts.type == BT_INTEGER)
660 /* Special case for ** operator. */
661 if (e->value.op.operator == INTRINSIC_POWER)
664 gfc_convert_type (e->value.op.op2, &e->ts, 2);
668 if (op1->ts.type == BT_INTEGER)
671 gfc_convert_type (e->value.op.op1, &e->ts, 2);
675 /* Real combined with complex. */
676 e->ts.type = BT_COMPLEX;
677 if (op1->ts.kind > op2->ts.kind)
678 e->ts.kind = op1->ts.kind;
680 e->ts.kind = op2->ts.kind;
681 if (op1->ts.type != BT_COMPLEX || op1->ts.kind != e->ts.kind)
682 gfc_convert_type (e->value.op.op1, &e->ts, 2);
683 if (op2->ts.type != BT_COMPLEX || op2->ts.kind != e->ts.kind)
684 gfc_convert_type (e->value.op.op2, &e->ts, 2);
692 check_specification_function (gfc_expr *e)
699 sym = e->symtree->n.sym;
701 /* F95, 7.1.6.2; F2003, 7.1.7 */
703 && sym->attr.function
705 && !sym->attr.intrinsic
706 && !sym->attr.recursive
707 && sym->attr.proc != PROC_INTERNAL
708 && sym->attr.proc != PROC_ST_FUNCTION
709 && sym->attr.proc != PROC_UNKNOWN
710 && sym->formal == NULL)
716 /* Function to determine if an expression is constant or not. This
717 function expects that the expression has already been simplified. */
720 gfc_is_constant_expr (gfc_expr *e)
723 gfc_actual_arglist *arg;
729 switch (e->expr_type)
732 rv = (gfc_is_constant_expr (e->value.op.op1)
733 && (e->value.op.op2 == NULL
734 || gfc_is_constant_expr (e->value.op.op2)));
742 /* Specification functions are constant. */
743 if (check_specification_function (e) == MATCH_YES)
749 /* Call to intrinsic with at least one argument. */
751 if (e->value.function.isym && e->value.function.actual)
753 for (arg = e->value.function.actual; arg; arg = arg->next)
755 if (!gfc_is_constant_expr (arg->expr))
769 rv = (gfc_is_constant_expr (e->ref->u.ss.start)
770 && gfc_is_constant_expr (e->ref->u.ss.end));
775 for (c = e->value.constructor; c; c = c->next)
776 if (!gfc_is_constant_expr (c->expr))
784 rv = gfc_constant_ac (e);
788 gfc_internal_error ("gfc_is_constant_expr(): Unknown expression type");
795 /* Try to collapse intrinsic expressions. */
798 simplify_intrinsic_op (gfc_expr *p, int type)
801 gfc_expr *op1, *op2, *result;
803 if (p->value.op.operator == INTRINSIC_USER)
806 op1 = p->value.op.op1;
807 op2 = p->value.op.op2;
808 op = p->value.op.operator;
810 if (gfc_simplify_expr (op1, type) == FAILURE)
812 if (gfc_simplify_expr (op2, type) == FAILURE)
815 if (!gfc_is_constant_expr (op1)
816 || (op2 != NULL && !gfc_is_constant_expr (op2)))
820 p->value.op.op1 = NULL;
821 p->value.op.op2 = NULL;
825 case INTRINSIC_PARENTHESES:
826 result = gfc_parentheses (op1);
829 case INTRINSIC_UPLUS:
830 result = gfc_uplus (op1);
833 case INTRINSIC_UMINUS:
834 result = gfc_uminus (op1);
838 result = gfc_add (op1, op2);
841 case INTRINSIC_MINUS:
842 result = gfc_subtract (op1, op2);
845 case INTRINSIC_TIMES:
846 result = gfc_multiply (op1, op2);
849 case INTRINSIC_DIVIDE:
850 result = gfc_divide (op1, op2);
853 case INTRINSIC_POWER:
854 result = gfc_power (op1, op2);
857 case INTRINSIC_CONCAT:
858 result = gfc_concat (op1, op2);
862 case INTRINSIC_EQ_OS:
863 result = gfc_eq (op1, op2, op);
867 case INTRINSIC_NE_OS:
868 result = gfc_ne (op1, op2, op);
872 case INTRINSIC_GT_OS:
873 result = gfc_gt (op1, op2, op);
877 case INTRINSIC_GE_OS:
878 result = gfc_ge (op1, op2, op);
882 case INTRINSIC_LT_OS:
883 result = gfc_lt (op1, op2, op);
887 case INTRINSIC_LE_OS:
888 result = gfc_le (op1, op2, op);
892 result = gfc_not (op1);
896 result = gfc_and (op1, op2);
900 result = gfc_or (op1, op2);
904 result = gfc_eqv (op1, op2);
908 result = gfc_neqv (op1, op2);
912 gfc_internal_error ("simplify_intrinsic_op(): Bad operator");
922 result->rank = p->rank;
923 result->where = p->where;
924 gfc_replace_expr (p, result);
930 /* Subroutine to simplify constructor expressions. Mutually recursive
931 with gfc_simplify_expr(). */
934 simplify_constructor (gfc_constructor *c, int type)
936 for (; c; c = c->next)
939 && (gfc_simplify_expr (c->iterator->start, type) == FAILURE
940 || gfc_simplify_expr (c->iterator->end, type) == FAILURE
941 || gfc_simplify_expr (c->iterator->step, type) == FAILURE))
944 if (c->expr && gfc_simplify_expr (c->expr, type) == FAILURE)
952 /* Pull a single array element out of an array constructor. */
955 find_array_element (gfc_constructor *cons, gfc_array_ref *ar,
956 gfc_constructor **rval)
958 unsigned long nelemen;
970 mpz_init_set_ui (offset, 0);
973 mpz_init_set_ui (span, 1);
974 for (i = 0; i < ar->dimen; i++)
976 e = gfc_copy_expr (ar->start[i]);
977 if (e->expr_type != EXPR_CONSTANT)
983 /* Check the bounds. */
985 && (mpz_cmp (e->value.integer, ar->as->upper[i]->value.integer) > 0
986 || mpz_cmp (e->value.integer,
987 ar->as->lower[i]->value.integer) < 0))
989 gfc_error ("index in dimension %d is out of bounds "
990 "at %L", i + 1, &ar->c_where[i]);
996 mpz_sub (delta, e->value.integer, ar->as->lower[i]->value.integer);
997 mpz_mul (delta, delta, span);
998 mpz_add (offset, offset, delta);
1000 mpz_set_ui (tmp, 1);
1001 mpz_add (tmp, tmp, ar->as->upper[i]->value.integer);
1002 mpz_sub (tmp, tmp, ar->as->lower[i]->value.integer);
1003 mpz_mul (span, span, tmp);
1008 for (nelemen = mpz_get_ui (offset); nelemen > 0; nelemen--)
1031 /* Find a component of a structure constructor. */
1033 static gfc_constructor *
1034 find_component_ref (gfc_constructor *cons, gfc_ref *ref)
1036 gfc_component *comp;
1037 gfc_component *pick;
1039 comp = ref->u.c.sym->components;
1040 pick = ref->u.c.component;
1041 while (comp != pick)
1051 /* Replace an expression with the contents of a constructor, removing
1052 the subobject reference in the process. */
1055 remove_subobject_ref (gfc_expr *p, gfc_constructor *cons)
1061 e->ref = p->ref->next;
1062 p->ref->next = NULL;
1063 gfc_replace_expr (p, e);
1067 /* Pull an array section out of an array constructor. */
1070 find_array_section (gfc_expr *expr, gfc_ref *ref)
1076 long unsigned one = 1;
1078 mpz_t start[GFC_MAX_DIMENSIONS];
1079 mpz_t end[GFC_MAX_DIMENSIONS];
1080 mpz_t stride[GFC_MAX_DIMENSIONS];
1081 mpz_t delta[GFC_MAX_DIMENSIONS];
1082 mpz_t ctr[GFC_MAX_DIMENSIONS];
1088 gfc_constructor *cons;
1089 gfc_constructor *base;
1095 gfc_constructor *vecsub[GFC_MAX_DIMENSIONS], *c;
1100 base = expr->value.constructor;
1101 expr->value.constructor = NULL;
1103 rank = ref->u.ar.as->rank;
1105 if (expr->shape == NULL)
1106 expr->shape = gfc_get_shape (rank);
1108 mpz_init_set_ui (delta_mpz, one);
1109 mpz_init_set_ui (nelts, one);
1112 /* Do the initialization now, so that we can cleanup without
1113 keeping track of where we were. */
1114 for (d = 0; d < rank; d++)
1116 mpz_init (delta[d]);
1117 mpz_init (start[d]);
1120 mpz_init (stride[d]);
1124 /* Build the counters to clock through the array reference. */
1126 for (d = 0; d < rank; d++)
1128 /* Make this stretch of code easier on the eye! */
1129 begin = ref->u.ar.start[d];
1130 finish = ref->u.ar.end[d];
1131 step = ref->u.ar.stride[d];
1132 lower = ref->u.ar.as->lower[d];
1133 upper = ref->u.ar.as->upper[d];
1135 if (ref->u.ar.dimen_type[d] == DIMEN_VECTOR) /* Vector subscript. */
1139 if (begin->expr_type != EXPR_ARRAY)
1145 gcc_assert (begin->rank == 1);
1146 gcc_assert (begin->shape);
1148 vecsub[d] = begin->value.constructor;
1149 mpz_set (ctr[d], vecsub[d]->expr->value.integer);
1150 mpz_mul (nelts, nelts, begin->shape[0]);
1151 mpz_set (expr->shape[shape_i++], begin->shape[0]);
1154 for (c = vecsub[d]; c; c = c->next)
1156 if (mpz_cmp (c->expr->value.integer, upper->value.integer) > 0
1157 || mpz_cmp (c->expr->value.integer,
1158 lower->value.integer) < 0)
1160 gfc_error ("index in dimension %d is out of bounds "
1161 "at %L", d + 1, &ref->u.ar.c_where[d]);
1169 if ((begin && begin->expr_type != EXPR_CONSTANT)
1170 || (finish && finish->expr_type != EXPR_CONSTANT)
1171 || (step && step->expr_type != EXPR_CONSTANT))
1177 /* Obtain the stride. */
1179 mpz_set (stride[d], step->value.integer);
1181 mpz_set_ui (stride[d], one);
1183 if (mpz_cmp_ui (stride[d], 0) == 0)
1184 mpz_set_ui (stride[d], one);
1186 /* Obtain the start value for the index. */
1188 mpz_set (start[d], begin->value.integer);
1190 mpz_set (start[d], lower->value.integer);
1192 mpz_set (ctr[d], start[d]);
1194 /* Obtain the end value for the index. */
1196 mpz_set (end[d], finish->value.integer);
1198 mpz_set (end[d], upper->value.integer);
1200 /* Separate 'if' because elements sometimes arrive with
1202 if (ref->u.ar.dimen_type[d] == DIMEN_ELEMENT)
1203 mpz_set (end [d], begin->value.integer);
1205 /* Check the bounds. */
1206 if (mpz_cmp (ctr[d], upper->value.integer) > 0
1207 || mpz_cmp (end[d], upper->value.integer) > 0
1208 || mpz_cmp (ctr[d], lower->value.integer) < 0
1209 || mpz_cmp (end[d], lower->value.integer) < 0)
1211 gfc_error ("index in dimension %d is out of bounds "
1212 "at %L", d + 1, &ref->u.ar.c_where[d]);
1217 /* Calculate the number of elements and the shape. */
1218 mpz_set (tmp_mpz, stride[d]);
1219 mpz_add (tmp_mpz, end[d], tmp_mpz);
1220 mpz_sub (tmp_mpz, tmp_mpz, ctr[d]);
1221 mpz_div (tmp_mpz, tmp_mpz, stride[d]);
1222 mpz_mul (nelts, nelts, tmp_mpz);
1224 /* An element reference reduces the rank of the expression; don't
1225 add anything to the shape array. */
1226 if (ref->u.ar.dimen_type[d] != DIMEN_ELEMENT)
1227 mpz_set (expr->shape[shape_i++], tmp_mpz);
1230 /* Calculate the 'stride' (=delta) for conversion of the
1231 counter values into the index along the constructor. */
1232 mpz_set (delta[d], delta_mpz);
1233 mpz_sub (tmp_mpz, upper->value.integer, lower->value.integer);
1234 mpz_add_ui (tmp_mpz, tmp_mpz, one);
1235 mpz_mul (delta_mpz, delta_mpz, tmp_mpz);
1242 /* Now clock through the array reference, calculating the index in
1243 the source constructor and transferring the elements to the new
1245 for (idx = 0; idx < (int) mpz_get_si (nelts); idx++)
1247 if (ref->u.ar.offset)
1248 mpz_set (ptr, ref->u.ar.offset->value.integer);
1250 mpz_init_set_ui (ptr, 0);
1253 for (d = 0; d < rank; d++)
1255 mpz_set (tmp_mpz, ctr[d]);
1256 mpz_sub (tmp_mpz, tmp_mpz, ref->u.ar.as->lower[d]->value.integer);
1257 mpz_mul (tmp_mpz, tmp_mpz, delta[d]);
1258 mpz_add (ptr, ptr, tmp_mpz);
1260 if (!incr_ctr) continue;
1262 if (ref->u.ar.dimen_type[d] == DIMEN_VECTOR) /* Vector subscript. */
1264 gcc_assert(vecsub[d]);
1266 if (!vecsub[d]->next)
1267 vecsub[d] = ref->u.ar.start[d]->value.constructor;
1270 vecsub[d] = vecsub[d]->next;
1273 mpz_set (ctr[d], vecsub[d]->expr->value.integer);
1277 mpz_add (ctr[d], ctr[d], stride[d]);
1279 if (mpz_cmp_ui (stride[d], 0) > 0
1280 ? mpz_cmp (ctr[d], end[d]) > 0
1281 : mpz_cmp (ctr[d], end[d]) < 0)
1282 mpz_set (ctr[d], start[d]);
1288 /* There must be a better way of dealing with negative strides
1289 than resetting the index and the constructor pointer! */
1290 if (mpz_cmp (ptr, index) < 0)
1292 mpz_set_ui (index, 0);
1296 while (mpz_cmp (ptr, index) > 0)
1298 mpz_add_ui (index, index, one);
1302 gfc_append_constructor (expr, gfc_copy_expr (cons->expr));
1310 mpz_clear (delta_mpz);
1311 mpz_clear (tmp_mpz);
1313 for (d = 0; d < rank; d++)
1315 mpz_clear (delta[d]);
1316 mpz_clear (start[d]);
1319 mpz_clear (stride[d]);
1321 gfc_free_constructor (base);
1325 /* Pull a substring out of an expression. */
1328 find_substring_ref (gfc_expr *p, gfc_expr **newp)
1334 if (p->ref->u.ss.start->expr_type != EXPR_CONSTANT
1335 || p->ref->u.ss.end->expr_type != EXPR_CONSTANT)
1338 *newp = gfc_copy_expr (p);
1339 chr = p->value.character.string;
1340 end = (int) mpz_get_ui (p->ref->u.ss.end->value.integer);
1341 start = (int) mpz_get_ui (p->ref->u.ss.start->value.integer);
1343 (*newp)->value.character.length = end - start + 1;
1344 strncpy ((*newp)->value.character.string, &chr[start - 1],
1345 (*newp)->value.character.length);
1351 /* Simplify a subobject reference of a constructor. This occurs when
1352 parameter variable values are substituted. */
1355 simplify_const_ref (gfc_expr *p)
1357 gfc_constructor *cons;
1362 switch (p->ref->type)
1365 switch (p->ref->u.ar.type)
1368 if (find_array_element (p->value.constructor, &p->ref->u.ar,
1375 remove_subobject_ref (p, cons);
1379 if (find_array_section (p, p->ref) == FAILURE)
1381 p->ref->u.ar.type = AR_FULL;
1386 if (p->ref->next != NULL
1387 && (p->ts.type == BT_CHARACTER || p->ts.type == BT_DERIVED))
1389 cons = p->value.constructor;
1390 for (; cons; cons = cons->next)
1392 cons->expr->ref = copy_ref (p->ref->next);
1393 simplify_const_ref (cons->expr);
1396 gfc_free_ref_list (p->ref);
1407 cons = find_component_ref (p->value.constructor, p->ref);
1408 remove_subobject_ref (p, cons);
1412 if (find_substring_ref (p, &newp) == FAILURE)
1415 gfc_replace_expr (p, newp);
1416 gfc_free_ref_list (p->ref);
1426 /* Simplify a chain of references. */
1429 simplify_ref_chain (gfc_ref *ref, int type)
1433 for (; ref; ref = ref->next)
1438 for (n = 0; n < ref->u.ar.dimen; n++)
1440 if (gfc_simplify_expr (ref->u.ar.start[n], type) == FAILURE)
1442 if (gfc_simplify_expr (ref->u.ar.end[n], type) == FAILURE)
1444 if (gfc_simplify_expr (ref->u.ar.stride[n], type) == FAILURE)
1450 if (gfc_simplify_expr (ref->u.ss.start, type) == FAILURE)
1452 if (gfc_simplify_expr (ref->u.ss.end, type) == FAILURE)
1464 /* Try to substitute the value of a parameter variable. */
1467 simplify_parameter_variable (gfc_expr *p, int type)
1472 e = gfc_copy_expr (p->symtree->n.sym->value);
1478 /* Do not copy subobject refs for constant. */
1479 if (e->expr_type != EXPR_CONSTANT && p->ref != NULL)
1480 e->ref = copy_ref (p->ref);
1481 t = gfc_simplify_expr (e, type);
1483 /* Only use the simplification if it eliminated all subobject references. */
1484 if (t == SUCCESS && !e->ref)
1485 gfc_replace_expr (p, e);
1492 /* Given an expression, simplify it by collapsing constant
1493 expressions. Most simplification takes place when the expression
1494 tree is being constructed. If an intrinsic function is simplified
1495 at some point, we get called again to collapse the result against
1498 We work by recursively simplifying expression nodes, simplifying
1499 intrinsic functions where possible, which can lead to further
1500 constant collapsing. If an operator has constant operand(s), we
1501 rip the expression apart, and rebuild it, hoping that it becomes
1504 The expression type is defined for:
1505 0 Basic expression parsing
1506 1 Simplifying array constructors -- will substitute
1508 Returns FAILURE on error, SUCCESS otherwise.
1509 NOTE: Will return SUCCESS even if the expression can not be simplified. */
1512 gfc_simplify_expr (gfc_expr *p, int type)
1514 gfc_actual_arglist *ap;
1519 switch (p->expr_type)
1526 for (ap = p->value.function.actual; ap; ap = ap->next)
1527 if (gfc_simplify_expr (ap->expr, type) == FAILURE)
1530 if (p->value.function.isym != NULL
1531 && gfc_intrinsic_func_interface (p, 1) == MATCH_ERROR)
1536 case EXPR_SUBSTRING:
1537 if (simplify_ref_chain (p->ref, type) == FAILURE)
1540 if (gfc_is_constant_expr (p))
1545 gfc_extract_int (p->ref->u.ss.start, &start);
1546 start--; /* Convert from one-based to zero-based. */
1547 gfc_extract_int (p->ref->u.ss.end, &end);
1548 s = gfc_getmem (end - start + 2);
1549 memcpy (s, p->value.character.string + start, end - start);
1550 s[end - start + 1] = '\0'; /* TODO: C-style string. */
1551 gfc_free (p->value.character.string);
1552 p->value.character.string = s;
1553 p->value.character.length = end - start;
1554 p->ts.cl = gfc_get_charlen ();
1555 p->ts.cl->next = gfc_current_ns->cl_list;
1556 gfc_current_ns->cl_list = p->ts.cl;
1557 p->ts.cl->length = gfc_int_expr (p->value.character.length);
1558 gfc_free_ref_list (p->ref);
1560 p->expr_type = EXPR_CONSTANT;
1565 if (simplify_intrinsic_op (p, type) == FAILURE)
1570 /* Only substitute array parameter variables if we are in an
1571 initialization expression, or we want a subsection. */
1572 if (p->symtree->n.sym->attr.flavor == FL_PARAMETER
1573 && (gfc_init_expr || p->ref
1574 || p->symtree->n.sym->value->expr_type != EXPR_ARRAY))
1576 if (simplify_parameter_variable (p, type) == FAILURE)
1583 gfc_simplify_iterator_var (p);
1586 /* Simplify subcomponent references. */
1587 if (simplify_ref_chain (p->ref, type) == FAILURE)
1592 case EXPR_STRUCTURE:
1594 if (simplify_ref_chain (p->ref, type) == FAILURE)
1597 if (simplify_constructor (p->value.constructor, type) == FAILURE)
1600 if (p->expr_type == EXPR_ARRAY && p->ref && p->ref->type == REF_ARRAY
1601 && p->ref->u.ar.type == AR_FULL)
1602 gfc_expand_constructor (p);
1604 if (simplify_const_ref (p) == FAILURE)
1614 /* Returns the type of an expression with the exception that iterator
1615 variables are automatically integers no matter what else they may
1621 if (e->expr_type == EXPR_VARIABLE && gfc_check_iter_variable (e) == SUCCESS)
1628 /* Check an intrinsic arithmetic operation to see if it is consistent
1629 with some type of expression. */
1631 static try check_init_expr (gfc_expr *);
1634 /* Scalarize an expression for an elemental intrinsic call. */
1637 scalarize_intrinsic_call (gfc_expr *e)
1639 gfc_actual_arglist *a, *b;
1640 gfc_constructor *args[5], *ctor, *new_ctor;
1641 gfc_expr *expr, *old;
1644 old = gfc_copy_expr (e);
1646 /* Assume that the old expression carries the type information and
1647 that the first arg carries all the shape information. */
1648 expr = gfc_copy_expr (old->value.function.actual->expr);
1649 gfc_free_constructor (expr->value.constructor);
1650 expr->value.constructor = NULL;
1653 expr->expr_type = EXPR_ARRAY;
1655 /* Copy the array argument constructors into an array, with nulls
1658 a = old->value.function.actual;
1659 for (; a; a = a->next)
1661 /* Check that this is OK for an initialization expression. */
1662 if (a->expr && check_init_expr (a->expr) == FAILURE)
1666 if (a->expr && a->expr->rank && a->expr->expr_type == EXPR_VARIABLE)
1668 rank[n] = a->expr->rank;
1669 ctor = a->expr->symtree->n.sym->value->value.constructor;
1670 args[n] = gfc_copy_constructor (ctor);
1672 else if (a->expr && a->expr->expr_type == EXPR_ARRAY)
1675 rank[n] = a->expr->rank;
1678 args[n] = gfc_copy_constructor (a->expr->value.constructor);
1685 for (i = 1; i < n; i++)
1686 if (rank[i] && rank[i] != rank[0])
1689 /* Using the first argument as the master, step through the array
1690 calling the function for each element and advancing the array
1691 constructors together. */
1694 for (; ctor; ctor = ctor->next)
1696 if (expr->value.constructor == NULL)
1697 expr->value.constructor
1698 = new_ctor = gfc_get_constructor ();
1701 new_ctor->next = gfc_get_constructor ();
1702 new_ctor = new_ctor->next;
1704 new_ctor->expr = gfc_copy_expr (old);
1705 gfc_free_actual_arglist (new_ctor->expr->value.function.actual);
1707 b = old->value.function.actual;
1708 for (i = 0; i < n; i++)
1711 new_ctor->expr->value.function.actual
1712 = a = gfc_get_actual_arglist ();
1715 a->next = gfc_get_actual_arglist ();
1719 a->expr = gfc_copy_expr (args[i]->expr);
1721 a->expr = gfc_copy_expr (b->expr);
1726 /* Simplify the function calls. */
1727 if (gfc_simplify_expr (new_ctor->expr, 0) == FAILURE)
1730 for (i = 0; i < n; i++)
1732 args[i] = args[i]->next;
1734 for (i = 1; i < n; i++)
1735 if (rank[i] && ((args[i] != NULL && args[0] == NULL)
1736 || (args[i] == NULL && args[0] != NULL)))
1742 gfc_free_expr (old);
1746 gfc_error_now ("elemental function arguments at %C are not compliant");
1749 gfc_free_expr (expr);
1750 gfc_free_expr (old);
1756 check_intrinsic_op (gfc_expr *e, try (*check_function) (gfc_expr *))
1758 gfc_expr *op1 = e->value.op.op1;
1759 gfc_expr *op2 = e->value.op.op2;
1761 if ((*check_function) (op1) == FAILURE)
1764 switch (e->value.op.operator)
1766 case INTRINSIC_UPLUS:
1767 case INTRINSIC_UMINUS:
1768 if (!numeric_type (et0 (op1)))
1773 case INTRINSIC_EQ_OS:
1775 case INTRINSIC_NE_OS:
1777 case INTRINSIC_GT_OS:
1779 case INTRINSIC_GE_OS:
1781 case INTRINSIC_LT_OS:
1783 case INTRINSIC_LE_OS:
1784 if ((*check_function) (op2) == FAILURE)
1787 if (!(et0 (op1) == BT_CHARACTER && et0 (op2) == BT_CHARACTER)
1788 && !(numeric_type (et0 (op1)) && numeric_type (et0 (op2))))
1790 gfc_error ("Numeric or CHARACTER operands are required in "
1791 "expression at %L", &e->where);
1796 case INTRINSIC_PLUS:
1797 case INTRINSIC_MINUS:
1798 case INTRINSIC_TIMES:
1799 case INTRINSIC_DIVIDE:
1800 case INTRINSIC_POWER:
1801 if ((*check_function) (op2) == FAILURE)
1804 if (!numeric_type (et0 (op1)) || !numeric_type (et0 (op2)))
1807 if (e->value.op.operator == INTRINSIC_POWER
1808 && check_function == check_init_expr && et0 (op2) != BT_INTEGER)
1810 if (gfc_notify_std (GFC_STD_F2003,"Fortran 2003: Noninteger "
1811 "exponent in an initialization "
1812 "expression at %L", &op2->where)
1819 case INTRINSIC_CONCAT:
1820 if ((*check_function) (op2) == FAILURE)
1823 if (et0 (op1) != BT_CHARACTER || et0 (op2) != BT_CHARACTER)
1825 gfc_error ("Concatenation operator in expression at %L "
1826 "must have two CHARACTER operands", &op1->where);
1830 if (op1->ts.kind != op2->ts.kind)
1832 gfc_error ("Concat operator at %L must concatenate strings of the "
1833 "same kind", &e->where);
1840 if (et0 (op1) != BT_LOGICAL)
1842 gfc_error (".NOT. operator in expression at %L must have a LOGICAL "
1843 "operand", &op1->where);
1852 case INTRINSIC_NEQV:
1853 if ((*check_function) (op2) == FAILURE)
1856 if (et0 (op1) != BT_LOGICAL || et0 (op2) != BT_LOGICAL)
1858 gfc_error ("LOGICAL operands are required in expression at %L",
1865 case INTRINSIC_PARENTHESES:
1869 gfc_error ("Only intrinsic operators can be used in expression at %L",
1877 gfc_error ("Numeric operands are required in expression at %L", &e->where);
1884 check_init_expr_arguments (gfc_expr *e)
1886 gfc_actual_arglist *ap;
1888 for (ap = e->value.function.actual; ap; ap = ap->next)
1889 if (check_init_expr (ap->expr) == FAILURE)
1895 /* F95, 7.1.6.1, Initialization expressions, (7)
1896 F2003, 7.1.7 Initialization expression, (8) */
1899 check_inquiry (gfc_expr *e, int not_restricted)
1902 const char *const *functions;
1904 static const char *const inquiry_func_f95[] = {
1905 "lbound", "shape", "size", "ubound",
1906 "bit_size", "len", "kind",
1907 "digits", "epsilon", "huge", "maxexponent", "minexponent",
1908 "precision", "radix", "range", "tiny",
1912 static const char *const inquiry_func_f2003[] = {
1913 "lbound", "shape", "size", "ubound",
1914 "bit_size", "len", "kind",
1915 "digits", "epsilon", "huge", "maxexponent", "minexponent",
1916 "precision", "radix", "range", "tiny",
1921 gfc_actual_arglist *ap;
1923 if (!e->value.function.isym
1924 || !e->value.function.isym->inquiry)
1927 /* An undeclared parameter will get us here (PR25018). */
1928 if (e->symtree == NULL)
1931 name = e->symtree->n.sym->name;
1933 functions = (gfc_option.warn_std & GFC_STD_F2003)
1934 ? inquiry_func_f2003 : inquiry_func_f95;
1936 for (i = 0; functions[i]; i++)
1937 if (strcmp (functions[i], name) == 0)
1940 if (functions[i] == NULL)
1942 gfc_error ("Inquiry function '%s' at %L is not permitted "
1943 "in an initialization expression", name, &e->where);
1947 /* At this point we have an inquiry function with a variable argument. The
1948 type of the variable might be undefined, but we need it now, because the
1949 arguments of these functions are not allowed to be undefined. */
1951 for (ap = e->value.function.actual; ap; ap = ap->next)
1956 if (ap->expr->ts.type == BT_UNKNOWN)
1958 if (ap->expr->symtree->n.sym->ts.type == BT_UNKNOWN
1959 && gfc_set_default_type (ap->expr->symtree->n.sym, 0, gfc_current_ns)
1963 ap->expr->ts = ap->expr->symtree->n.sym->ts;
1966 /* Assumed character length will not reduce to a constant expression
1967 with LEN, as required by the standard. */
1968 if (i == 5 && not_restricted
1969 && ap->expr->symtree->n.sym->ts.type == BT_CHARACTER
1970 && ap->expr->symtree->n.sym->ts.cl->length == NULL)
1972 gfc_error ("assumed character length variable '%s' in constant "
1973 "expression at %L", e->symtree->n.sym->name, &e->where);
1976 else if (not_restricted && check_init_expr (ap->expr) == FAILURE)
1984 /* F95, 7.1.6.1, Initialization expressions, (5)
1985 F2003, 7.1.7 Initialization expression, (5) */
1988 check_transformational (gfc_expr *e)
1990 static const char * const trans_func_f95[] = {
1991 "repeat", "reshape", "selected_int_kind",
1992 "selected_real_kind", "transfer", "trim", NULL
1998 if (!e->value.function.isym
1999 || !e->value.function.isym->transformational)
2002 name = e->symtree->n.sym->name;
2004 /* NULL() is dealt with below. */
2005 if (strcmp ("null", name) == 0)
2008 for (i = 0; trans_func_f95[i]; i++)
2009 if (strcmp (trans_func_f95[i], name) == 0)
2012 /* FIXME, F2003: implement translation of initialization
2013 expressions before enabling this check. For F95, error
2014 out if the transformational function is not in the list. */
2016 if (trans_func_f95[i] == NULL
2017 && gfc_notify_std (GFC_STD_F2003,
2018 "transformational intrinsic '%s' at %L is not permitted "
2019 "in an initialization expression", name, &e->where) == FAILURE)
2022 if (trans_func_f95[i] == NULL)
2024 gfc_error("transformational intrinsic '%s' at %L is not permitted "
2025 "in an initialization expression", name, &e->where);
2030 return check_init_expr_arguments (e);
2034 /* F95, 7.1.6.1, Initialization expressions, (6)
2035 F2003, 7.1.7 Initialization expression, (6) */
2038 check_null (gfc_expr *e)
2040 if (strcmp ("null", e->symtree->n.sym->name) != 0)
2043 return check_init_expr_arguments (e);
2048 check_elemental (gfc_expr *e)
2050 if (!e->value.function.isym
2051 || !e->value.function.isym->elemental)
2054 if ((e->ts.type != BT_INTEGER || e->ts.type != BT_CHARACTER)
2055 && gfc_notify_std (GFC_STD_F2003, "Extension: Evaluation of "
2056 "nonstandard initialization expression at %L",
2057 &e->where) == FAILURE)
2060 return check_init_expr_arguments (e);
2065 check_conversion (gfc_expr *e)
2067 if (!e->value.function.isym
2068 || !e->value.function.isym->conversion)
2071 return check_init_expr_arguments (e);
2075 /* Verify that an expression is an initialization expression. A side
2076 effect is that the expression tree is reduced to a single constant
2077 node if all goes well. This would normally happen when the
2078 expression is constructed but function references are assumed to be
2079 intrinsics in the context of initialization expressions. If
2080 FAILURE is returned an error message has been generated. */
2083 check_init_expr (gfc_expr *e)
2087 gfc_intrinsic_sym *isym;
2092 switch (e->expr_type)
2095 t = check_intrinsic_op (e, check_init_expr);
2097 t = gfc_simplify_expr (e, 0);
2104 if ((m = check_specification_function (e)) != MATCH_YES)
2106 if ((m = gfc_intrinsic_func_interface (e, 0)) != MATCH_YES)
2108 gfc_error ("Function '%s' in initialization expression at %L "
2109 "must be an intrinsic or a specification function",
2110 e->symtree->n.sym->name, &e->where);
2114 if ((m = check_conversion (e)) == MATCH_NO
2115 && (m = check_inquiry (e, 1)) == MATCH_NO
2116 && (m = check_null (e)) == MATCH_NO
2117 && (m = check_transformational (e)) == MATCH_NO
2118 && (m = check_elemental (e)) == MATCH_NO)
2120 gfc_error ("Intrinsic function '%s' at %L is not permitted "
2121 "in an initialization expression",
2122 e->symtree->n.sym->name, &e->where);
2126 /* Try to scalarize an elemental intrinsic function that has an
2128 isym = gfc_find_function (e->symtree->n.sym->name);
2129 if (isym && isym->elemental
2130 && e->value.function.actual->expr->expr_type == EXPR_ARRAY)
2132 if ((t = scalarize_intrinsic_call (e)) == SUCCESS)
2138 t = gfc_simplify_expr (e, 0);
2145 if (gfc_check_iter_variable (e) == SUCCESS)
2148 if (e->symtree->n.sym->attr.flavor == FL_PARAMETER)
2150 t = simplify_parameter_variable (e, 0);
2154 if (gfc_in_match_data ())
2159 if (e->symtree->n.sym->as)
2161 switch (e->symtree->n.sym->as->type)
2163 case AS_ASSUMED_SIZE:
2164 gfc_error ("assumed size array '%s' at %L is not permitted "
2165 "in an initialization expression",
2166 e->symtree->n.sym->name, &e->where);
2169 case AS_ASSUMED_SHAPE:
2170 gfc_error ("assumed shape array '%s' at %L is not permitted "
2171 "in an initialization expression",
2172 e->symtree->n.sym->name, &e->where);
2176 gfc_error ("deferred array '%s' at %L is not permitted "
2177 "in an initialization expression",
2178 e->symtree->n.sym->name, &e->where);
2186 gfc_error ("Parameter '%s' at %L has not been declared or is "
2187 "a variable, which does not reduce to a constant "
2188 "expression", e->symtree->n.sym->name, &e->where);
2197 case EXPR_SUBSTRING:
2198 t = check_init_expr (e->ref->u.ss.start);
2202 t = check_init_expr (e->ref->u.ss.end);
2204 t = gfc_simplify_expr (e, 0);
2208 case EXPR_STRUCTURE:
2209 t = gfc_check_constructor (e, check_init_expr);
2213 t = gfc_check_constructor (e, check_init_expr);
2217 t = gfc_expand_constructor (e);
2221 t = gfc_check_constructor_type (e);
2225 gfc_internal_error ("check_init_expr(): Unknown expression type");
2232 /* Match an initialization expression. We work by first matching an
2233 expression, then reducing it to a constant. */
2236 gfc_match_init_expr (gfc_expr **result)
2242 m = gfc_match_expr (&expr);
2247 t = gfc_resolve_expr (expr);
2249 t = check_init_expr (expr);
2254 gfc_free_expr (expr);
2258 if (expr->expr_type == EXPR_ARRAY
2259 && (gfc_check_constructor_type (expr) == FAILURE
2260 || gfc_expand_constructor (expr) == FAILURE))
2262 gfc_free_expr (expr);
2266 /* Not all inquiry functions are simplified to constant expressions
2267 so it is necessary to call check_inquiry again. */
2268 if (!gfc_is_constant_expr (expr) && check_inquiry (expr, 1) != MATCH_YES
2269 && !gfc_in_match_data ())
2271 gfc_error ("Initialization expression didn't reduce %C");
2281 static try check_restricted (gfc_expr *);
2283 /* Given an actual argument list, test to see that each argument is a
2284 restricted expression and optionally if the expression type is
2285 integer or character. */
2288 restricted_args (gfc_actual_arglist *a)
2290 for (; a; a = a->next)
2292 if (check_restricted (a->expr) == FAILURE)
2300 /************* Restricted/specification expressions *************/
2303 /* Make sure a non-intrinsic function is a specification function. */
2306 external_spec_function (gfc_expr *e)
2310 f = e->value.function.esym;
2312 if (f->attr.proc == PROC_ST_FUNCTION)
2314 gfc_error ("Specification function '%s' at %L cannot be a statement "
2315 "function", f->name, &e->where);
2319 if (f->attr.proc == PROC_INTERNAL)
2321 gfc_error ("Specification function '%s' at %L cannot be an internal "
2322 "function", f->name, &e->where);
2326 if (!f->attr.pure && !f->attr.elemental)
2328 gfc_error ("Specification function '%s' at %L must be PURE", f->name,
2333 if (f->attr.recursive)
2335 gfc_error ("Specification function '%s' at %L cannot be RECURSIVE",
2336 f->name, &e->where);
2340 return restricted_args (e->value.function.actual);
2344 /* Check to see that a function reference to an intrinsic is a
2345 restricted expression. */
2348 restricted_intrinsic (gfc_expr *e)
2350 /* TODO: Check constraints on inquiry functions. 7.1.6.2 (7). */
2351 if (check_inquiry (e, 0) == MATCH_YES)
2354 return restricted_args (e->value.function.actual);
2358 /* Verify that an expression is a restricted expression. Like its
2359 cousin check_init_expr(), an error message is generated if we
2363 check_restricted (gfc_expr *e)
2371 switch (e->expr_type)
2374 t = check_intrinsic_op (e, check_restricted);
2376 t = gfc_simplify_expr (e, 0);
2381 t = e->value.function.esym ? external_spec_function (e)
2382 : restricted_intrinsic (e);
2386 sym = e->symtree->n.sym;
2389 if (sym->attr.optional)
2391 gfc_error ("Dummy argument '%s' at %L cannot be OPTIONAL",
2392 sym->name, &e->where);
2396 if (sym->attr.intent == INTENT_OUT)
2398 gfc_error ("Dummy argument '%s' at %L cannot be INTENT(OUT)",
2399 sym->name, &e->where);
2403 /* gfc_is_formal_arg broadcasts that a formal argument list is being
2404 processed in resolve.c(resolve_formal_arglist). This is done so
2405 that host associated dummy array indices are accepted (PR23446).
2406 This mechanism also does the same for the specification expressions
2407 of array-valued functions. */
2408 if (sym->attr.in_common
2409 || sym->attr.use_assoc
2411 || sym->ns != gfc_current_ns
2412 || (sym->ns->proc_name != NULL
2413 && sym->ns->proc_name->attr.flavor == FL_MODULE)
2414 || (gfc_is_formal_arg () && (sym->ns == gfc_current_ns)))
2420 gfc_error ("Variable '%s' cannot appear in the expression at %L",
2421 sym->name, &e->where);
2430 case EXPR_SUBSTRING:
2431 t = gfc_specification_expr (e->ref->u.ss.start);
2435 t = gfc_specification_expr (e->ref->u.ss.end);
2437 t = gfc_simplify_expr (e, 0);
2441 case EXPR_STRUCTURE:
2442 t = gfc_check_constructor (e, check_restricted);
2446 t = gfc_check_constructor (e, check_restricted);
2450 gfc_internal_error ("check_restricted(): Unknown expression type");
2457 /* Check to see that an expression is a specification expression. If
2458 we return FAILURE, an error has been generated. */
2461 gfc_specification_expr (gfc_expr *e)
2467 if (e->ts.type != BT_INTEGER)
2469 gfc_error ("Expression at %L must be of INTEGER type", &e->where);
2475 gfc_error ("Expression at %L must be scalar", &e->where);
2479 if (gfc_simplify_expr (e, 0) == FAILURE)
2482 return check_restricted (e);
2486 /************** Expression conformance checks. *************/
2488 /* Given two expressions, make sure that the arrays are conformable. */
2491 gfc_check_conformance (const char *optype_msgid, gfc_expr *op1, gfc_expr *op2)
2493 int op1_flag, op2_flag, d;
2494 mpz_t op1_size, op2_size;
2497 if (op1->rank == 0 || op2->rank == 0)
2500 if (op1->rank != op2->rank)
2502 gfc_error ("Incompatible ranks in %s at %L", _(optype_msgid),
2509 for (d = 0; d < op1->rank; d++)
2511 op1_flag = gfc_array_dimen_size (op1, d, &op1_size) == SUCCESS;
2512 op2_flag = gfc_array_dimen_size (op2, d, &op2_size) == SUCCESS;
2514 if (op1_flag && op2_flag && mpz_cmp (op1_size, op2_size) != 0)
2516 gfc_error ("different shape for %s at %L on dimension %d (%d/%d)",
2517 _(optype_msgid), &op1->where, d + 1,
2518 (int) mpz_get_si (op1_size),
2519 (int) mpz_get_si (op2_size));
2525 mpz_clear (op1_size);
2527 mpz_clear (op2_size);
2537 /* Given an assignable expression and an arbitrary expression, make
2538 sure that the assignment can take place. */
2541 gfc_check_assign (gfc_expr *lvalue, gfc_expr *rvalue, int conform)
2547 sym = lvalue->symtree->n.sym;
2549 /* Check INTENT(IN), unless the object itself is the component or
2550 sub-component of a pointer. */
2551 has_pointer = sym->attr.pointer;
2553 for (ref = lvalue->ref; ref; ref = ref->next)
2554 if (ref->type == REF_COMPONENT && ref->u.c.component->pointer)
2560 if (!has_pointer && sym->attr.intent == INTENT_IN)
2562 gfc_error ("Cannot assign to INTENT(IN) variable '%s' at %L",
2563 sym->name, &lvalue->where);
2567 /* 12.5.2.2, Note 12.26: The result variable is very similar to any other
2568 variable local to a function subprogram. Its existence begins when
2569 execution of the function is initiated and ends when execution of the
2570 function is terminated...
2571 Therefore, the left hand side is no longer a variable, when it is: */
2572 if (sym->attr.flavor == FL_PROCEDURE && sym->attr.proc != PROC_ST_FUNCTION
2573 && !sym->attr.external)
2578 /* (i) Use associated; */
2579 if (sym->attr.use_assoc)
2582 /* (ii) The assignment is in the main program; or */
2583 if (gfc_current_ns->proc_name->attr.is_main_program)
2586 /* (iii) A module or internal procedure... */
2587 if ((gfc_current_ns->proc_name->attr.proc == PROC_INTERNAL
2588 || gfc_current_ns->proc_name->attr.proc == PROC_MODULE)
2589 && gfc_current_ns->parent
2590 && (!(gfc_current_ns->parent->proc_name->attr.function
2591 || gfc_current_ns->parent->proc_name->attr.subroutine)
2592 || gfc_current_ns->parent->proc_name->attr.is_main_program))
2594 /* ... that is not a function... */
2595 if (!gfc_current_ns->proc_name->attr.function)
2598 /* ... or is not an entry and has a different name. */
2599 if (!sym->attr.entry && sym->name != gfc_current_ns->proc_name->name)
2605 gfc_error ("'%s' at %L is not a VALUE", sym->name, &lvalue->where);
2610 if (rvalue->rank != 0 && lvalue->rank != rvalue->rank)
2612 gfc_error ("Incompatible ranks %d and %d in assignment at %L",
2613 lvalue->rank, rvalue->rank, &lvalue->where);
2617 if (lvalue->ts.type == BT_UNKNOWN)
2619 gfc_error ("Variable type is UNKNOWN in assignment at %L",
2624 if (rvalue->expr_type == EXPR_NULL)
2626 if (lvalue->symtree->n.sym->attr.pointer
2627 && lvalue->symtree->n.sym->attr.data)
2631 gfc_error ("NULL appears on right-hand side in assignment at %L",
2637 if (sym->attr.cray_pointee
2638 && lvalue->ref != NULL
2639 && lvalue->ref->u.ar.type == AR_FULL
2640 && lvalue->ref->u.ar.as->cp_was_assumed)
2642 gfc_error ("Vector assignment to assumed-size Cray Pointee at %L "
2643 "is illegal", &lvalue->where);
2647 /* This is possibly a typo: x = f() instead of x => f(). */
2648 if (gfc_option.warn_surprising
2649 && rvalue->expr_type == EXPR_FUNCTION
2650 && rvalue->symtree->n.sym->attr.pointer)
2651 gfc_warning ("POINTER valued function appears on right-hand side of "
2652 "assignment at %L", &rvalue->where);
2654 /* Check size of array assignments. */
2655 if (lvalue->rank != 0 && rvalue->rank != 0
2656 && gfc_check_conformance ("Array assignment", lvalue, rvalue) != SUCCESS)
2659 if (gfc_compare_types (&lvalue->ts, &rvalue->ts))
2664 /* Numeric can be converted to any other numeric. And Hollerith can be
2665 converted to any other type. */
2666 if ((gfc_numeric_ts (&lvalue->ts) && gfc_numeric_ts (&rvalue->ts))
2667 || rvalue->ts.type == BT_HOLLERITH)
2670 if (lvalue->ts.type == BT_LOGICAL && rvalue->ts.type == BT_LOGICAL)
2673 gfc_error ("Incompatible types in assignment at %L, %s to %s",
2674 &rvalue->where, gfc_typename (&rvalue->ts),
2675 gfc_typename (&lvalue->ts));
2680 return gfc_convert_type (rvalue, &lvalue->ts, 1);
2684 /* Check that a pointer assignment is OK. We first check lvalue, and
2685 we only check rvalue if it's not an assignment to NULL() or a
2686 NULLIFY statement. */
2689 gfc_check_pointer_assign (gfc_expr *lvalue, gfc_expr *rvalue)
2691 symbol_attribute attr;
2694 int pointer, check_intent_in;
2696 if (lvalue->symtree->n.sym->ts.type == BT_UNKNOWN)
2698 gfc_error ("Pointer assignment target is not a POINTER at %L",
2703 if (lvalue->symtree->n.sym->attr.flavor == FL_PROCEDURE
2704 && lvalue->symtree->n.sym->attr.use_assoc)
2706 gfc_error ("'%s' in the pointer assignment at %L cannot be an "
2707 "l-value since it is a procedure",
2708 lvalue->symtree->n.sym->name, &lvalue->where);
2713 /* Check INTENT(IN), unless the object itself is the component or
2714 sub-component of a pointer. */
2715 check_intent_in = 1;
2716 pointer = lvalue->symtree->n.sym->attr.pointer;
2718 for (ref = lvalue->ref; ref; ref = ref->next)
2721 check_intent_in = 0;
2723 if (ref->type == REF_COMPONENT && ref->u.c.component->pointer)
2727 if (check_intent_in && lvalue->symtree->n.sym->attr.intent == INTENT_IN)
2729 gfc_error ("Cannot assign to INTENT(IN) variable '%s' at %L",
2730 lvalue->symtree->n.sym->name, &lvalue->where);
2736 gfc_error ("Pointer assignment to non-POINTER at %L", &lvalue->where);
2740 is_pure = gfc_pure (NULL);
2742 if (is_pure && gfc_impure_variable (lvalue->symtree->n.sym))
2744 gfc_error ("Bad pointer object in PURE procedure at %L", &lvalue->where);
2748 /* If rvalue is a NULL() or NULLIFY, we're done. Otherwise the type,
2749 kind, etc for lvalue and rvalue must match, and rvalue must be a
2750 pure variable if we're in a pure function. */
2751 if (rvalue->expr_type == EXPR_NULL && rvalue->ts.type == BT_UNKNOWN)
2754 if (!gfc_compare_types (&lvalue->ts, &rvalue->ts))
2756 gfc_error ("Different types in pointer assignment at %L",
2761 if (lvalue->ts.kind != rvalue->ts.kind)
2763 gfc_error ("Different kind type parameters in pointer "
2764 "assignment at %L", &lvalue->where);
2768 if (lvalue->rank != rvalue->rank)
2770 gfc_error ("Different ranks in pointer assignment at %L",
2775 /* Now punt if we are dealing with a NULLIFY(X) or X = NULL(X). */
2776 if (rvalue->expr_type == EXPR_NULL)
2779 if (lvalue->ts.type == BT_CHARACTER
2780 && lvalue->ts.cl && rvalue->ts.cl
2781 && lvalue->ts.cl->length && rvalue->ts.cl->length
2782 && abs (gfc_dep_compare_expr (lvalue->ts.cl->length,
2783 rvalue->ts.cl->length)) == 1)
2785 gfc_error ("Different character lengths in pointer "
2786 "assignment at %L", &lvalue->where);
2790 attr = gfc_expr_attr (rvalue);
2791 if (!attr.target && !attr.pointer)
2793 gfc_error ("Pointer assignment target is neither TARGET "
2794 "nor POINTER at %L", &rvalue->where);
2798 if (is_pure && gfc_impure_variable (rvalue->symtree->n.sym))
2800 gfc_error ("Bad target in pointer assignment in PURE "
2801 "procedure at %L", &rvalue->where);
2804 if (gfc_has_vector_index (rvalue))
2806 gfc_error ("Pointer assignment with vector subscript "
2807 "on rhs at %L", &rvalue->where);
2811 if (attr.protected && attr.use_assoc)
2813 gfc_error ("Pointer assigment target has PROTECTED "
2814 "attribute at %L", &rvalue->where);
2822 /* Relative of gfc_check_assign() except that the lvalue is a single
2823 symbol. Used for initialization assignments. */
2826 gfc_check_assign_symbol (gfc_symbol *sym, gfc_expr *rvalue)
2831 memset (&lvalue, '\0', sizeof (gfc_expr));
2833 lvalue.expr_type = EXPR_VARIABLE;
2834 lvalue.ts = sym->ts;
2836 lvalue.rank = sym->as->rank;
2837 lvalue.symtree = (gfc_symtree *) gfc_getmem (sizeof (gfc_symtree));
2838 lvalue.symtree->n.sym = sym;
2839 lvalue.where = sym->declared_at;
2841 if (sym->attr.pointer)
2842 r = gfc_check_pointer_assign (&lvalue, rvalue);
2844 r = gfc_check_assign (&lvalue, rvalue, 1);
2846 gfc_free (lvalue.symtree);
2852 /* Get an expression for a default initializer. */
2855 gfc_default_initializer (gfc_typespec *ts)
2857 gfc_constructor *tail;
2863 /* See if we have a default initializer. */
2864 for (c = ts->derived->components; c; c = c->next)
2866 if ((c->initializer || c->allocatable) && init == NULL)
2867 init = gfc_get_expr ();
2873 /* Build the constructor. */
2874 init->expr_type = EXPR_STRUCTURE;
2876 init->where = ts->derived->declared_at;
2878 for (c = ts->derived->components; c; c = c->next)
2881 init->value.constructor = tail = gfc_get_constructor ();
2884 tail->next = gfc_get_constructor ();
2889 tail->expr = gfc_copy_expr (c->initializer);
2893 tail->expr = gfc_get_expr ();
2894 tail->expr->expr_type = EXPR_NULL;
2895 tail->expr->ts = c->ts;
2902 /* Given a symbol, create an expression node with that symbol as a
2903 variable. If the symbol is array valued, setup a reference of the
2907 gfc_get_variable_expr (gfc_symtree *var)
2911 e = gfc_get_expr ();
2912 e->expr_type = EXPR_VARIABLE;
2914 e->ts = var->n.sym->ts;
2916 if (var->n.sym->as != NULL)
2918 e->rank = var->n.sym->as->rank;
2919 e->ref = gfc_get_ref ();
2920 e->ref->type = REF_ARRAY;
2921 e->ref->u.ar.type = AR_FULL;
2928 /* Traverse expr, marking all EXPR_VARIABLE symbols referenced. */
2931 gfc_expr_set_symbols_referenced (gfc_expr *expr)
2933 gfc_actual_arglist *arg;
2940 switch (expr->expr_type)
2943 gfc_expr_set_symbols_referenced (expr->value.op.op1);
2944 gfc_expr_set_symbols_referenced (expr->value.op.op2);
2948 for (arg = expr->value.function.actual; arg; arg = arg->next)
2949 gfc_expr_set_symbols_referenced (arg->expr);
2953 gfc_set_sym_referenced (expr->symtree->n.sym);
2958 case EXPR_SUBSTRING:
2961 case EXPR_STRUCTURE:
2963 for (c = expr->value.constructor; c; c = c->next)
2964 gfc_expr_set_symbols_referenced (c->expr);
2972 for (ref = expr->ref; ref; ref = ref->next)
2976 for (i = 0; i < ref->u.ar.dimen; i++)
2978 gfc_expr_set_symbols_referenced (ref->u.ar.start[i]);
2979 gfc_expr_set_symbols_referenced (ref->u.ar.end[i]);
2980 gfc_expr_set_symbols_referenced (ref->u.ar.stride[i]);
2988 gfc_expr_set_symbols_referenced (ref->u.ss.start);
2989 gfc_expr_set_symbols_referenced (ref->u.ss.end);