1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2008, Free Software Foundation, Inc. *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 3, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License along with GCC; see the file COPYING3. If not see *
19 * <http://www.gnu.org/licenses/>. *
21 * GNAT was originally developed by the GNAT team at New York University. *
22 * Extensive contributions were provided by Ada Core Technologies Inc. *
24 ****************************************************************************/
28 #include "coretypes.h"
50 static tree find_common_type (tree, tree);
51 static bool contains_save_expr_p (tree);
52 static tree contains_null_expr (tree);
53 static tree compare_arrays (tree, tree, tree);
54 static tree nonbinary_modular_operation (enum tree_code, tree, tree, tree);
55 static tree build_simple_component_ref (tree, tree, tree, bool);
57 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
60 This preparation consists of taking the ordinary representation of
61 an expression expr and producing a valid tree boolean expression
62 describing whether expr is nonzero. We could simply always do
64 build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
66 but we optimize comparisons, &&, ||, and !.
68 The resulting type should always be the same as the input type.
69 This function is simpler than the corresponding C version since
70 the only possible operands will be things of Boolean type. */
73 gnat_truthvalue_conversion (tree expr)
75 tree type = TREE_TYPE (expr);
77 switch (TREE_CODE (expr))
79 case EQ_EXPR: case NE_EXPR: case LE_EXPR: case GE_EXPR:
80 case LT_EXPR: case GT_EXPR:
81 case TRUTH_ANDIF_EXPR:
90 return (integer_zerop (expr)
91 ? build_int_cst (type, 0)
92 : build_int_cst (type, 1));
95 return (real_zerop (expr)
96 ? fold_convert (type, integer_zero_node)
97 : fold_convert (type, integer_one_node));
100 /* Distribute the conversion into the arms of a COND_EXPR. */
102 tree arg1 = gnat_truthvalue_conversion (TREE_OPERAND (expr, 1));
103 tree arg2 = gnat_truthvalue_conversion (TREE_OPERAND (expr, 2));
104 return fold_build3 (COND_EXPR, type, TREE_OPERAND (expr, 0),
109 return build_binary_op (NE_EXPR, type, expr,
110 fold_convert (type, integer_zero_node));
114 /* Return the base type of TYPE. */
117 get_base_type (tree type)
119 if (TREE_CODE (type) == RECORD_TYPE
120 && TYPE_JUSTIFIED_MODULAR_P (type))
121 type = TREE_TYPE (TYPE_FIELDS (type));
123 while (TREE_TYPE (type)
124 && (TREE_CODE (type) == INTEGER_TYPE
125 || TREE_CODE (type) == REAL_TYPE))
126 type = TREE_TYPE (type);
131 /* EXP is a GCC tree representing an address. See if we can find how
132 strictly the object at that address is aligned. Return that alignment
133 in bits. If we don't know anything about the alignment, return 0. */
136 known_alignment (tree exp)
138 unsigned int this_alignment;
139 unsigned int lhs, rhs;
141 switch (TREE_CODE (exp))
144 case VIEW_CONVERT_EXPR:
145 case NON_LVALUE_EXPR:
146 /* Conversions between pointers and integers don't change the alignment
147 of the underlying object. */
148 this_alignment = known_alignment (TREE_OPERAND (exp, 0));
152 /* The value of a COMPOUND_EXPR is that of it's second operand. */
153 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
158 /* If two address are added, the alignment of the result is the
159 minimum of the two alignments. */
160 lhs = known_alignment (TREE_OPERAND (exp, 0));
161 rhs = known_alignment (TREE_OPERAND (exp, 1));
162 this_alignment = MIN (lhs, rhs);
165 case POINTER_PLUS_EXPR:
166 lhs = known_alignment (TREE_OPERAND (exp, 0));
167 rhs = known_alignment (TREE_OPERAND (exp, 1));
168 /* If we don't know the alignment of the offset, we assume that
171 this_alignment = lhs;
173 this_alignment = MIN (lhs, rhs);
177 /* If there is a choice between two values, use the smallest one. */
178 lhs = known_alignment (TREE_OPERAND (exp, 1));
179 rhs = known_alignment (TREE_OPERAND (exp, 2));
180 this_alignment = MIN (lhs, rhs);
185 unsigned HOST_WIDE_INT c = TREE_INT_CST_LOW (exp);
186 /* The first part of this represents the lowest bit in the constant,
187 but it is originally in bytes, not bits. */
188 this_alignment = MIN (BITS_PER_UNIT * (c & -c), BIGGEST_ALIGNMENT);
193 /* If we know the alignment of just one side, use it. Otherwise,
194 use the product of the alignments. */
195 lhs = known_alignment (TREE_OPERAND (exp, 0));
196 rhs = known_alignment (TREE_OPERAND (exp, 1));
199 this_alignment = rhs;
201 this_alignment = lhs;
203 this_alignment = MIN (lhs * rhs, BIGGEST_ALIGNMENT);
207 /* A bit-and expression is as aligned as the maximum alignment of the
208 operands. We typically get here for a complex lhs and a constant
209 negative power of two on the rhs to force an explicit alignment, so
210 don't bother looking at the lhs. */
211 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
215 this_alignment = expr_align (TREE_OPERAND (exp, 0));
219 /* For other pointer expressions, we assume that the pointed-to object
220 is at least as aligned as the pointed-to type. Beware that we can
221 have a dummy type here (e.g. a Taft Amendment type), for which the
222 alignment is meaningless and should be ignored. */
223 if (POINTER_TYPE_P (TREE_TYPE (exp))
224 && !TYPE_IS_DUMMY_P (TREE_TYPE (TREE_TYPE (exp))))
225 this_alignment = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp)));
231 return this_alignment;
234 /* We have a comparison or assignment operation on two types, T1 and T2, which
235 are either both array types or both record types. T1 is assumed to be for
236 the left hand side operand, and T2 for the right hand side. Return the
237 type that both operands should be converted to for the operation, if any.
238 Otherwise return zero. */
241 find_common_type (tree t1, tree t2)
243 /* ??? As of today, various constructs lead here with types of different
244 sizes even when both constants (e.g. tagged types, packable vs regular
245 component types, padded vs unpadded types, ...). While some of these
246 would better be handled upstream (types should be made consistent before
247 calling into build_binary_op), some others are really expected and we
248 have to be careful. */
250 /* We must prevent writing more than what the target may hold if this is for
251 an assignment and the case of tagged types is handled in build_binary_op
252 so use the lhs type if it is known to be smaller, or of constant size and
253 the rhs type is not, whatever the modes. We also force t1 in case of
254 constant size equality to minimize occurrences of view conversions on the
255 lhs of assignments. */
256 if (TREE_CONSTANT (TYPE_SIZE (t1))
257 && (!TREE_CONSTANT (TYPE_SIZE (t2))
258 || !tree_int_cst_lt (TYPE_SIZE (t2), TYPE_SIZE (t1))))
261 /* Otherwise, if the lhs type is non-BLKmode, use it. Note that we know
262 that we will not have any alignment problems since, if we did, the
263 non-BLKmode type could not have been used. */
264 if (TYPE_MODE (t1) != BLKmode)
267 /* If the rhs type is of constant size, use it whatever the modes. At
268 this point it is known to be smaller, or of constant size and the
270 if (TREE_CONSTANT (TYPE_SIZE (t2)))
273 /* Otherwise, if the rhs type is non-BLKmode, use it. */
274 if (TYPE_MODE (t2) != BLKmode)
277 /* In this case, both types have variable size and BLKmode. It's
278 probably best to leave the "type mismatch" because changing it
279 could cause a bad self-referential reference. */
283 /* See if EXP contains a SAVE_EXPR in a position where we would
286 ??? This is a real kludge, but is probably the best approach short
287 of some very general solution. */
290 contains_save_expr_p (tree exp)
292 switch (TREE_CODE (exp))
297 case ADDR_EXPR: case INDIRECT_REF:
299 CASE_CONVERT: case VIEW_CONVERT_EXPR:
300 return contains_save_expr_p (TREE_OPERAND (exp, 0));
305 unsigned HOST_WIDE_INT ix;
307 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), ix, value)
308 if (contains_save_expr_p (value))
318 /* See if EXP contains a NULL_EXPR in an expression we use for sizes. Return
319 it if so. This is used to detect types whose sizes involve computations
320 that are known to raise Constraint_Error. */
323 contains_null_expr (tree exp)
327 if (TREE_CODE (exp) == NULL_EXPR)
330 switch (TREE_CODE_CLASS (TREE_CODE (exp)))
333 return contains_null_expr (TREE_OPERAND (exp, 0));
337 tem = contains_null_expr (TREE_OPERAND (exp, 0));
341 return contains_null_expr (TREE_OPERAND (exp, 1));
344 switch (TREE_CODE (exp))
347 return contains_null_expr (TREE_OPERAND (exp, 0));
350 tem = contains_null_expr (TREE_OPERAND (exp, 0));
354 tem = contains_null_expr (TREE_OPERAND (exp, 1));
358 return contains_null_expr (TREE_OPERAND (exp, 2));
369 /* Return an expression tree representing an equality comparison of
370 A1 and A2, two objects of ARRAY_TYPE. The returned expression should
371 be of type RESULT_TYPE
373 Two arrays are equal in one of two ways: (1) if both have zero length
374 in some dimension (not necessarily the same dimension) or (2) if the
375 lengths in each dimension are equal and the data is equal. We perform the
376 length tests in as efficient a manner as possible. */
379 compare_arrays (tree result_type, tree a1, tree a2)
381 tree t1 = TREE_TYPE (a1);
382 tree t2 = TREE_TYPE (a2);
383 tree result = convert (result_type, integer_one_node);
384 tree a1_is_null = convert (result_type, integer_zero_node);
385 tree a2_is_null = convert (result_type, integer_zero_node);
386 bool length_zero_p = false;
388 /* Process each dimension separately and compare the lengths. If any
389 dimension has a size known to be zero, set SIZE_ZERO_P to 1 to
390 suppress the comparison of the data. */
391 while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
393 tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
394 tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
395 tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
396 tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
397 tree bt = get_base_type (TREE_TYPE (lb1));
398 tree length1 = fold_build2 (MINUS_EXPR, bt, ub1, lb1);
399 tree length2 = fold_build2 (MINUS_EXPR, bt, ub2, lb2);
402 tree comparison, this_a1_is_null, this_a2_is_null;
404 /* If the length of the first array is a constant, swap our operands
405 unless the length of the second array is the constant zero.
406 Note that we have set the `length' values to the length - 1. */
407 if (TREE_CODE (length1) == INTEGER_CST
408 && !integer_zerop (fold_build2 (PLUS_EXPR, bt, length2,
409 convert (bt, integer_one_node))))
411 tem = a1, a1 = a2, a2 = tem;
412 tem = t1, t1 = t2, t2 = tem;
413 tem = lb1, lb1 = lb2, lb2 = tem;
414 tem = ub1, ub1 = ub2, ub2 = tem;
415 tem = length1, length1 = length2, length2 = tem;
416 tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
419 /* If the length of this dimension in the second array is the constant
420 zero, we can just go inside the original bounds for the first
421 array and see if last < first. */
422 if (integer_zerop (fold_build2 (PLUS_EXPR, bt, length2,
423 convert (bt, integer_one_node))))
425 tree ub = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
426 tree lb = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
428 comparison = build_binary_op (LT_EXPR, result_type, ub, lb);
429 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
430 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
432 length_zero_p = true;
433 this_a1_is_null = comparison;
434 this_a2_is_null = convert (result_type, integer_one_node);
437 /* If the length is some other constant value, we know that the
438 this dimension in the first array cannot be superflat, so we
439 can just use its length from the actual stored bounds. */
440 else if (TREE_CODE (length2) == INTEGER_CST)
442 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
443 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
444 ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
445 lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
446 nbt = get_base_type (TREE_TYPE (ub1));
449 = build_binary_op (EQ_EXPR, result_type,
450 build_binary_op (MINUS_EXPR, nbt, ub1, lb1),
451 build_binary_op (MINUS_EXPR, nbt, ub2, lb2));
453 /* Note that we know that UB2 and LB2 are constant and hence
454 cannot contain a PLACEHOLDER_EXPR. */
456 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
457 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
459 this_a1_is_null = build_binary_op (LT_EXPR, result_type, ub1, lb1);
460 this_a2_is_null = convert (result_type, integer_zero_node);
463 /* Otherwise compare the computed lengths. */
466 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
467 length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
470 = build_binary_op (EQ_EXPR, result_type, length1, length2);
473 = build_binary_op (LT_EXPR, result_type, length1,
474 convert (bt, integer_zero_node));
476 = build_binary_op (LT_EXPR, result_type, length2,
477 convert (bt, integer_zero_node));
480 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
483 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
484 this_a1_is_null, a1_is_null);
485 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
486 this_a2_is_null, a2_is_null);
492 /* Unless the size of some bound is known to be zero, compare the
493 data in the array. */
496 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
499 a1 = convert (type, a1), a2 = convert (type, a2);
501 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result,
502 fold_build2 (EQ_EXPR, result_type, a1, a2));
506 /* The result is also true if both sizes are zero. */
507 result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
508 build_binary_op (TRUTH_ANDIF_EXPR, result_type,
509 a1_is_null, a2_is_null),
512 /* If either operand contains SAVE_EXPRs, they have to be evaluated before
513 starting the comparison above since the place it would be otherwise
514 evaluated would be wrong. */
516 if (contains_save_expr_p (a1))
517 result = build2 (COMPOUND_EXPR, result_type, a1, result);
519 if (contains_save_expr_p (a2))
520 result = build2 (COMPOUND_EXPR, result_type, a2, result);
525 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
526 type TYPE. We know that TYPE is a modular type with a nonbinary
530 nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
533 tree modulus = TYPE_MODULUS (type);
534 unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
535 unsigned int precision;
536 bool unsignedp = true;
540 /* If this is an addition of a constant, convert it to a subtraction
541 of a constant since we can do that faster. */
542 if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
544 rhs = fold_build2 (MINUS_EXPR, type, modulus, rhs);
545 op_code = MINUS_EXPR;
548 /* For the logical operations, we only need PRECISION bits. For
549 addition and subtraction, we need one more and for multiplication we
550 need twice as many. But we never want to make a size smaller than
552 if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
553 needed_precision += 1;
554 else if (op_code == MULT_EXPR)
555 needed_precision *= 2;
557 precision = MAX (needed_precision, TYPE_PRECISION (op_type));
559 /* Unsigned will do for everything but subtraction. */
560 if (op_code == MINUS_EXPR)
563 /* If our type is the wrong signedness or isn't wide enough, make a new
564 type and convert both our operands to it. */
565 if (TYPE_PRECISION (op_type) < precision
566 || TYPE_UNSIGNED (op_type) != unsignedp)
568 /* Copy the node so we ensure it can be modified to make it modular. */
569 op_type = copy_node (gnat_type_for_size (precision, unsignedp));
570 modulus = convert (op_type, modulus);
571 SET_TYPE_MODULUS (op_type, modulus);
572 TYPE_MODULAR_P (op_type) = 1;
573 lhs = convert (op_type, lhs);
574 rhs = convert (op_type, rhs);
577 /* Do the operation, then we'll fix it up. */
578 result = fold_build2 (op_code, op_type, lhs, rhs);
580 /* For multiplication, we have no choice but to do a full modulus
581 operation. However, we want to do this in the narrowest
583 if (op_code == MULT_EXPR)
585 tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
586 modulus = convert (div_type, modulus);
587 SET_TYPE_MODULUS (div_type, modulus);
588 TYPE_MODULAR_P (div_type) = 1;
589 result = convert (op_type,
590 fold_build2 (TRUNC_MOD_EXPR, div_type,
591 convert (div_type, result), modulus));
594 /* For subtraction, add the modulus back if we are negative. */
595 else if (op_code == MINUS_EXPR)
597 result = save_expr (result);
598 result = fold_build3 (COND_EXPR, op_type,
599 fold_build2 (LT_EXPR, integer_type_node, result,
600 convert (op_type, integer_zero_node)),
601 fold_build2 (PLUS_EXPR, op_type, result, modulus),
605 /* For the other operations, subtract the modulus if we are >= it. */
608 result = save_expr (result);
609 result = fold_build3 (COND_EXPR, op_type,
610 fold_build2 (GE_EXPR, integer_type_node,
612 fold_build2 (MINUS_EXPR, op_type,
617 return convert (type, result);
620 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
621 desired for the result. Usually the operation is to be performed
622 in that type. For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
623 in which case the type to be used will be derived from the operands.
625 This function is very much unlike the ones for C and C++ since we
626 have already done any type conversion and matching required. All we
627 have to do here is validate the work done by SEM and handle subtypes. */
630 build_binary_op (enum tree_code op_code, tree result_type,
631 tree left_operand, tree right_operand)
633 tree left_type = TREE_TYPE (left_operand);
634 tree right_type = TREE_TYPE (right_operand);
635 tree left_base_type = get_base_type (left_type);
636 tree right_base_type = get_base_type (right_type);
637 tree operation_type = result_type;
638 tree best_type = NULL_TREE;
639 tree modulus, result;
640 bool has_side_effects = false;
643 && TREE_CODE (operation_type) == RECORD_TYPE
644 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
645 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
648 && !AGGREGATE_TYPE_P (operation_type)
649 && TYPE_EXTRA_SUBTYPE_P (operation_type))
650 operation_type = get_base_type (operation_type);
652 modulus = (operation_type
653 && TREE_CODE (operation_type) == INTEGER_TYPE
654 && TYPE_MODULAR_P (operation_type)
655 ? TYPE_MODULUS (operation_type) : NULL_TREE);
660 /* If there were integral or pointer conversions on the LHS, remove
661 them; we'll be putting them back below if needed. Likewise for
662 conversions between array and record types, except for justified
663 modular types. But don't do this if the right operand is not
664 BLKmode (for packed arrays) unless we are not changing the mode. */
665 while ((CONVERT_EXPR_P (left_operand)
666 || TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
667 && (((INTEGRAL_TYPE_P (left_type)
668 || POINTER_TYPE_P (left_type))
669 && (INTEGRAL_TYPE_P (TREE_TYPE
670 (TREE_OPERAND (left_operand, 0)))
671 || POINTER_TYPE_P (TREE_TYPE
672 (TREE_OPERAND (left_operand, 0)))))
673 || (((TREE_CODE (left_type) == RECORD_TYPE
674 && !TYPE_JUSTIFIED_MODULAR_P (left_type))
675 || TREE_CODE (left_type) == ARRAY_TYPE)
676 && ((TREE_CODE (TREE_TYPE
677 (TREE_OPERAND (left_operand, 0)))
679 || (TREE_CODE (TREE_TYPE
680 (TREE_OPERAND (left_operand, 0)))
682 && (TYPE_MODE (right_type) == BLKmode
683 || (TYPE_MODE (left_type)
684 == TYPE_MODE (TREE_TYPE
686 (left_operand, 0))))))))
688 left_operand = TREE_OPERAND (left_operand, 0);
689 left_type = TREE_TYPE (left_operand);
692 /* If a class-wide type may be involved, force use of the RHS type. */
693 if ((TREE_CODE (right_type) == RECORD_TYPE
694 || TREE_CODE (right_type) == UNION_TYPE)
695 && TYPE_ALIGN_OK (right_type))
696 operation_type = right_type;
698 /* If we are copying between padded objects with compatible types, use
699 the padded view of the objects, this is very likely more efficient.
700 Likewise for a padded that is assigned a constructor, in order to
701 avoid putting a VIEW_CONVERT_EXPR on the LHS. But don't do this if
702 we wouldn't have actually copied anything. */
703 else if (TREE_CODE (left_type) == RECORD_TYPE
704 && TYPE_IS_PADDING_P (left_type)
705 && TREE_CONSTANT (TYPE_SIZE (left_type))
706 && ((TREE_CODE (right_operand) == COMPONENT_REF
707 && TREE_CODE (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
710 (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
711 && gnat_types_compatible_p
713 TREE_TYPE (TREE_OPERAND (right_operand, 0))))
714 || TREE_CODE (right_operand) == CONSTRUCTOR)
715 && !integer_zerop (TYPE_SIZE (right_type)))
716 operation_type = left_type;
718 /* Find the best type to use for copying between aggregate types. */
719 else if (((TREE_CODE (left_type) == ARRAY_TYPE
720 && TREE_CODE (right_type) == ARRAY_TYPE)
721 || (TREE_CODE (left_type) == RECORD_TYPE
722 && TREE_CODE (right_type) == RECORD_TYPE))
723 && (best_type = find_common_type (left_type, right_type)))
724 operation_type = best_type;
726 /* Otherwise use the LHS type. */
727 else if (!operation_type)
728 operation_type = left_type;
730 /* Ensure everything on the LHS is valid. If we have a field reference,
731 strip anything that get_inner_reference can handle. Then remove any
732 conversions between types having the same code and mode. And mark
733 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
734 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
735 result = left_operand;
738 tree restype = TREE_TYPE (result);
740 if (TREE_CODE (result) == COMPONENT_REF
741 || TREE_CODE (result) == ARRAY_REF
742 || TREE_CODE (result) == ARRAY_RANGE_REF)
743 while (handled_component_p (result))
744 result = TREE_OPERAND (result, 0);
745 else if (TREE_CODE (result) == REALPART_EXPR
746 || TREE_CODE (result) == IMAGPART_EXPR
747 || (CONVERT_EXPR_P (result)
748 && (((TREE_CODE (restype)
749 == TREE_CODE (TREE_TYPE
750 (TREE_OPERAND (result, 0))))
751 && (TYPE_MODE (TREE_TYPE
752 (TREE_OPERAND (result, 0)))
753 == TYPE_MODE (restype)))
754 || TYPE_ALIGN_OK (restype))))
755 result = TREE_OPERAND (result, 0);
756 else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
758 TREE_ADDRESSABLE (result) = 1;
759 result = TREE_OPERAND (result, 0);
765 gcc_assert (TREE_CODE (result) == INDIRECT_REF
766 || TREE_CODE (result) == NULL_EXPR
769 /* Convert the right operand to the operation type unless it is
770 either already of the correct type or if the type involves a
771 placeholder, since the RHS may not have the same record type. */
772 if (operation_type != right_type
773 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type)))
775 right_operand = convert (operation_type, right_operand);
776 right_type = operation_type;
779 /* If the left operand is not of the same type as the operation
780 type, wrap it up in a VIEW_CONVERT_EXPR. */
781 if (left_type != operation_type)
782 left_operand = unchecked_convert (operation_type, left_operand, false);
784 has_side_effects = true;
790 operation_type = TREE_TYPE (left_type);
792 /* ... fall through ... */
794 case ARRAY_RANGE_REF:
795 /* First look through conversion between type variants. Note that
796 this changes neither the operation type nor the type domain. */
797 if (TREE_CODE (left_operand) == VIEW_CONVERT_EXPR
798 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand, 0)))
799 == TYPE_MAIN_VARIANT (left_type))
801 left_operand = TREE_OPERAND (left_operand, 0);
802 left_type = TREE_TYPE (left_operand);
805 /* Then convert the right operand to its base type. This will
806 prevent unneeded signedness conversions when sizetype is wider than
808 right_operand = convert (right_base_type, right_operand);
809 right_operand = convert (TYPE_DOMAIN (left_type), right_operand);
811 if (!TREE_CONSTANT (right_operand)
812 || !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
813 gnat_mark_addressable (left_operand);
822 gcc_assert (!POINTER_TYPE_P (left_type));
824 /* ... fall through ... */
828 /* If either operand is a NULL_EXPR, just return a new one. */
829 if (TREE_CODE (left_operand) == NULL_EXPR)
830 return build2 (op_code, result_type,
831 build1 (NULL_EXPR, integer_type_node,
832 TREE_OPERAND (left_operand, 0)),
835 else if (TREE_CODE (right_operand) == NULL_EXPR)
836 return build2 (op_code, result_type,
837 build1 (NULL_EXPR, integer_type_node,
838 TREE_OPERAND (right_operand, 0)),
841 /* If either object is a justified modular types, get the
842 fields from within. */
843 if (TREE_CODE (left_type) == RECORD_TYPE
844 && TYPE_JUSTIFIED_MODULAR_P (left_type))
846 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
848 left_type = TREE_TYPE (left_operand);
849 left_base_type = get_base_type (left_type);
852 if (TREE_CODE (right_type) == RECORD_TYPE
853 && TYPE_JUSTIFIED_MODULAR_P (right_type))
855 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
857 right_type = TREE_TYPE (right_operand);
858 right_base_type = get_base_type (right_type);
861 /* If both objects are arrays, compare them specially. */
862 if ((TREE_CODE (left_type) == ARRAY_TYPE
863 || (TREE_CODE (left_type) == INTEGER_TYPE
864 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
865 && (TREE_CODE (right_type) == ARRAY_TYPE
866 || (TREE_CODE (right_type) == INTEGER_TYPE
867 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
869 result = compare_arrays (result_type, left_operand, right_operand);
871 if (op_code == NE_EXPR)
872 result = invert_truthvalue (result);
874 gcc_assert (op_code == EQ_EXPR);
879 /* Otherwise, the base types must be the same unless the objects are
880 fat pointers or records. If we have records, use the best type and
881 convert both operands to that type. */
882 if (left_base_type != right_base_type)
884 if (TYPE_FAT_POINTER_P (left_base_type)
885 && TYPE_FAT_POINTER_P (right_base_type)
886 && TYPE_MAIN_VARIANT (left_base_type)
887 == TYPE_MAIN_VARIANT (right_base_type))
888 best_type = left_base_type;
889 else if (TREE_CODE (left_base_type) == RECORD_TYPE
890 && TREE_CODE (right_base_type) == RECORD_TYPE)
892 /* The only way these are permitted to be the same is if both
893 types have the same name. In that case, one of them must
894 not be self-referential. Use that one as the best type.
895 Even better is if one is of fixed size. */
896 gcc_assert (TYPE_NAME (left_base_type)
897 && (TYPE_NAME (left_base_type)
898 == TYPE_NAME (right_base_type)));
900 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
901 best_type = left_base_type;
902 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
903 best_type = right_base_type;
904 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
905 best_type = left_base_type;
906 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
907 best_type = right_base_type;
914 left_operand = convert (best_type, left_operand);
915 right_operand = convert (best_type, right_operand);
918 /* If we are comparing a fat pointer against zero, we need to
919 just compare the data pointer. */
920 else if (TYPE_FAT_POINTER_P (left_base_type)
921 && TREE_CODE (right_operand) == CONSTRUCTOR
922 && integer_zerop (VEC_index (constructor_elt,
923 CONSTRUCTOR_ELTS (right_operand),
927 right_operand = build_component_ref (left_operand, NULL_TREE,
928 TYPE_FIELDS (left_base_type),
930 left_operand = convert (TREE_TYPE (right_operand),
935 left_operand = convert (left_base_type, left_operand);
936 right_operand = convert (right_base_type, right_operand);
942 case PREINCREMENT_EXPR:
943 case PREDECREMENT_EXPR:
944 case POSTINCREMENT_EXPR:
945 case POSTDECREMENT_EXPR:
946 /* In these, the result type and the left operand type should be the
947 same. Do the operation in the base type of those and convert the
948 right operand (which is an integer) to that type.
950 Note that these operations are only used in loop control where
951 we guarantee that no overflow can occur. So nothing special need
952 be done for modular types. */
954 gcc_assert (left_type == result_type);
955 operation_type = get_base_type (result_type);
956 left_operand = convert (operation_type, left_operand);
957 right_operand = convert (operation_type, right_operand);
958 has_side_effects = true;
966 /* The RHS of a shift can be any type. Also, ignore any modulus
967 (we used to abort, but this is needed for unchecked conversion
968 to modular types). Otherwise, processing is the same as normal. */
969 gcc_assert (operation_type == left_base_type);
971 left_operand = convert (operation_type, left_operand);
974 case TRUTH_ANDIF_EXPR:
975 case TRUTH_ORIF_EXPR:
979 left_operand = gnat_truthvalue_conversion (left_operand);
980 right_operand = gnat_truthvalue_conversion (right_operand);
986 /* For binary modulus, if the inputs are in range, so are the
988 if (modulus && integer_pow2p (modulus))
993 gcc_assert (TREE_TYPE (result_type) == left_base_type
994 && TREE_TYPE (result_type) == right_base_type);
995 left_operand = convert (left_base_type, left_operand);
996 right_operand = convert (right_base_type, right_operand);
999 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
1000 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
1001 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
1002 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
1003 /* These always produce results lower than either operand. */
1004 modulus = NULL_TREE;
1007 case POINTER_PLUS_EXPR:
1008 gcc_assert (operation_type == left_base_type
1009 && sizetype == right_base_type);
1010 left_operand = convert (operation_type, left_operand);
1011 right_operand = convert (sizetype, right_operand);
1016 /* Avoid doing arithmetics in BOOLEAN_TYPE like the other compilers.
1017 Contrary to C, Ada doesn't allow arithmetics in Standard.Boolean
1018 but we can generate addition or subtraction for 'Succ and 'Pred. */
1019 if (operation_type && TREE_CODE (operation_type) == BOOLEAN_TYPE)
1020 operation_type = left_base_type = right_base_type = integer_type_node;
1025 /* The result type should be the same as the base types of the
1026 both operands (and they should be the same). Convert
1027 everything to the result type. */
1029 gcc_assert (operation_type == left_base_type
1030 && left_base_type == right_base_type);
1031 left_operand = convert (operation_type, left_operand);
1032 right_operand = convert (operation_type, right_operand);
1035 if (modulus && !integer_pow2p (modulus))
1037 result = nonbinary_modular_operation (op_code, operation_type,
1038 left_operand, right_operand);
1039 modulus = NULL_TREE;
1041 /* If either operand is a NULL_EXPR, just return a new one. */
1042 else if (TREE_CODE (left_operand) == NULL_EXPR)
1043 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
1044 else if (TREE_CODE (right_operand) == NULL_EXPR)
1045 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
1046 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
1047 result = fold (build4 (op_code, operation_type, left_operand,
1048 right_operand, NULL_TREE, NULL_TREE));
1051 = fold_build2 (op_code, operation_type, left_operand, right_operand);
1053 TREE_SIDE_EFFECTS (result) |= has_side_effects;
1054 TREE_CONSTANT (result)
1055 |= (TREE_CONSTANT (left_operand) & TREE_CONSTANT (right_operand)
1056 && op_code != ARRAY_REF && op_code != ARRAY_RANGE_REF);
1058 if ((op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
1059 && TYPE_VOLATILE (operation_type))
1060 TREE_THIS_VOLATILE (result) = 1;
1062 /* If we are working with modular types, perform the MOD operation
1063 if something above hasn't eliminated the need for it. */
1065 result = fold_build2 (FLOOR_MOD_EXPR, operation_type, result,
1066 convert (operation_type, modulus));
1068 if (result_type && result_type != operation_type)
1069 result = convert (result_type, result);
1074 /* Similar, but for unary operations. */
1077 build_unary_op (enum tree_code op_code, tree result_type, tree operand)
1079 tree type = TREE_TYPE (operand);
1080 tree base_type = get_base_type (type);
1081 tree operation_type = result_type;
1083 bool side_effects = false;
1086 && TREE_CODE (operation_type) == RECORD_TYPE
1087 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
1088 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
1091 && !AGGREGATE_TYPE_P (operation_type)
1092 && TYPE_EXTRA_SUBTYPE_P (operation_type))
1093 operation_type = get_base_type (operation_type);
1099 if (!operation_type)
1100 result_type = operation_type = TREE_TYPE (type);
1102 gcc_assert (result_type == TREE_TYPE (type));
1104 result = fold_build1 (op_code, operation_type, operand);
1107 case TRUTH_NOT_EXPR:
1108 gcc_assert (result_type == base_type);
1109 result = invert_truthvalue (gnat_truthvalue_conversion (operand));
1112 case ATTR_ADDR_EXPR:
1114 switch (TREE_CODE (operand))
1117 case UNCONSTRAINED_ARRAY_REF:
1118 result = TREE_OPERAND (operand, 0);
1120 /* Make sure the type here is a pointer, not a reference.
1121 GCC wants pointer types for function addresses. */
1123 result_type = build_pointer_type (type);
1125 /* If the underlying object can alias everything, propagate the
1126 property since we are effectively retrieving the object. */
1127 if (POINTER_TYPE_P (TREE_TYPE (result))
1128 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1130 if (TREE_CODE (result_type) == POINTER_TYPE
1131 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1133 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1134 TYPE_MODE (result_type),
1136 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1137 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1139 = build_reference_type_for_mode (TREE_TYPE (result_type),
1140 TYPE_MODE (result_type),
1147 TREE_TYPE (result) = type = build_pointer_type (type);
1151 case ARRAY_RANGE_REF:
1154 /* If this is for 'Address, find the address of the prefix and
1155 add the offset to the field. Otherwise, do this the normal
1157 if (op_code == ATTR_ADDR_EXPR)
1159 HOST_WIDE_INT bitsize;
1160 HOST_WIDE_INT bitpos;
1162 enum machine_mode mode;
1163 int unsignedp, volatilep;
1165 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1166 &mode, &unsignedp, &volatilep,
1169 /* If INNER is a padding type whose field has a self-referential
1170 size, convert to that inner type. We know the offset is zero
1171 and we need to have that type visible. */
1172 if (TREE_CODE (TREE_TYPE (inner)) == RECORD_TYPE
1173 && TYPE_IS_PADDING_P (TREE_TYPE (inner))
1174 && (CONTAINS_PLACEHOLDER_P
1175 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1176 (TREE_TYPE (inner)))))))
1177 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1180 /* Compute the offset as a byte offset from INNER. */
1182 offset = size_zero_node;
1184 if (bitpos % BITS_PER_UNIT != 0)
1186 ("taking address of object not aligned on storage unit?",
1189 offset = size_binop (PLUS_EXPR, offset,
1190 size_int (bitpos / BITS_PER_UNIT));
1192 /* Take the address of INNER, convert the offset to void *, and
1193 add then. It will later be converted to the desired result
1195 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1196 inner = convert (ptr_void_type_node, inner);
1197 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1199 result = convert (build_pointer_type (TREE_TYPE (operand)),
1206 /* If this is just a constructor for a padded record, we can
1207 just take the address of the single field and convert it to
1208 a pointer to our type. */
1209 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
1211 result = (VEC_index (constructor_elt,
1212 CONSTRUCTOR_ELTS (operand),
1216 result = convert (build_pointer_type (TREE_TYPE (operand)),
1217 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1224 if (AGGREGATE_TYPE_P (type)
1225 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1226 return build_unary_op (ADDR_EXPR, result_type,
1227 TREE_OPERAND (operand, 0));
1229 /* ... fallthru ... */
1231 case VIEW_CONVERT_EXPR:
1232 /* If this just a variant conversion or if the conversion doesn't
1233 change the mode, get the result type from this type and go down.
1234 This is needed for conversions of CONST_DECLs, to eventually get
1235 to the address of their CORRESPONDING_VARs. */
1236 if ((TYPE_MAIN_VARIANT (type)
1237 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1238 || (TYPE_MODE (type) != BLKmode
1239 && (TYPE_MODE (type)
1240 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1241 return build_unary_op (ADDR_EXPR,
1242 (result_type ? result_type
1243 : build_pointer_type (type)),
1244 TREE_OPERAND (operand, 0));
1248 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1250 /* ... fall through ... */
1255 /* If we are taking the address of a padded record whose field is
1256 contains a template, take the address of the template. */
1257 if (TREE_CODE (type) == RECORD_TYPE
1258 && TYPE_IS_PADDING_P (type)
1259 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1260 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1262 type = TREE_TYPE (TYPE_FIELDS (type));
1263 operand = convert (type, operand);
1266 if (type != error_mark_node)
1267 operation_type = build_pointer_type (type);
1269 gnat_mark_addressable (operand);
1270 result = fold_build1 (ADDR_EXPR, operation_type, operand);
1273 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1277 /* If we want to refer to an entire unconstrained array,
1278 make up an expression to do so. This will never survive to
1279 the backend. If TYPE is a thin pointer, first convert the
1280 operand to a fat pointer. */
1281 if (TYPE_THIN_POINTER_P (type)
1282 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1285 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1287 type = TREE_TYPE (operand);
1290 if (TYPE_FAT_POINTER_P (type))
1292 result = build1 (UNCONSTRAINED_ARRAY_REF,
1293 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1294 TREE_READONLY (result) = TREE_STATIC (result)
1295 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1297 else if (TREE_CODE (operand) == ADDR_EXPR)
1298 result = TREE_OPERAND (operand, 0);
1302 result = fold_build1 (op_code, TREE_TYPE (type), operand);
1303 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1307 = (!TYPE_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1313 tree modulus = ((operation_type
1314 && TREE_CODE (operation_type) == INTEGER_TYPE
1315 && TYPE_MODULAR_P (operation_type))
1316 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1317 int mod_pow2 = modulus && integer_pow2p (modulus);
1319 /* If this is a modular type, there are various possibilities
1320 depending on the operation and whether the modulus is a
1321 power of two or not. */
1325 gcc_assert (operation_type == base_type);
1326 operand = convert (operation_type, operand);
1328 /* The fastest in the negate case for binary modulus is
1329 the straightforward code; the TRUNC_MOD_EXPR below
1330 is an AND operation. */
1331 if (op_code == NEGATE_EXPR && mod_pow2)
1332 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1333 fold_build1 (NEGATE_EXPR, operation_type,
1337 /* For nonbinary negate case, return zero for zero operand,
1338 else return the modulus minus the operand. If the modulus
1339 is a power of two minus one, we can do the subtraction
1340 as an XOR since it is equivalent and faster on most machines. */
1341 else if (op_code == NEGATE_EXPR && !mod_pow2)
1343 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1345 convert (operation_type,
1346 integer_one_node))))
1347 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1350 result = fold_build2 (MINUS_EXPR, operation_type,
1353 result = fold_build3 (COND_EXPR, operation_type,
1354 fold_build2 (NE_EXPR,
1359 integer_zero_node)),
1364 /* For the NOT cases, we need a constant equal to
1365 the modulus minus one. For a binary modulus, we
1366 XOR against the constant and subtract the operand from
1367 that constant for nonbinary modulus. */
1369 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1370 convert (operation_type,
1374 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1377 result = fold_build2 (MINUS_EXPR, operation_type,
1385 /* ... fall through ... */
1388 gcc_assert (operation_type == base_type);
1389 result = fold_build1 (op_code, operation_type,
1390 convert (operation_type, operand));
1395 TREE_SIDE_EFFECTS (result) = 1;
1396 if (TREE_CODE (result) == INDIRECT_REF)
1397 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1400 if (result_type && TREE_TYPE (result) != result_type)
1401 result = convert (result_type, result);
1406 /* Similar, but for COND_EXPR. */
1409 build_cond_expr (tree result_type, tree condition_operand,
1410 tree true_operand, tree false_operand)
1413 bool addr_p = false;
1415 /* The front-end verifies that result, true and false operands have same base
1416 type. Convert everything to the result type. */
1418 true_operand = convert (result_type, true_operand);
1419 false_operand = convert (result_type, false_operand);
1421 /* If the result type is unconstrained, take the address of
1422 the operands and then dereference our result. */
1423 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1424 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1427 result_type = build_pointer_type (result_type);
1428 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1429 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1432 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1433 true_operand, false_operand);
1435 /* If either operand is a SAVE_EXPR (possibly surrounded by
1436 arithmetic, make sure it gets done. */
1437 true_operand = skip_simple_arithmetic (true_operand);
1438 false_operand = skip_simple_arithmetic (false_operand);
1440 if (TREE_CODE (true_operand) == SAVE_EXPR)
1441 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1443 if (TREE_CODE (false_operand) == SAVE_EXPR)
1444 result = build2 (COMPOUND_EXPR, result_type, false_operand, result);
1446 /* ??? Seems the code above is wrong, as it may move ahead of the COND
1447 SAVE_EXPRs with side effects and not shared by both arms. */
1450 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1455 /* Similar, but for RETURN_EXPR. If RESULT_DECL is non-zero, build
1456 a RETURN_EXPR around the assignment of RET_VAL to RESULT_DECL.
1457 If RESULT_DECL is zero, build a bare RETURN_EXPR. */
1460 build_return_expr (tree result_decl, tree ret_val)
1466 /* The gimplifier explicitly enforces the following invariant:
1475 As a consequence, type-homogeneity dictates that we use the type
1476 of the RESULT_DECL as the operation type. */
1478 tree operation_type = TREE_TYPE (result_decl);
1480 /* Convert the right operand to the operation type. Note that
1481 it's the same transformation as in the MODIFY_EXPR case of
1482 build_binary_op with the additional guarantee that the type
1483 cannot involve a placeholder, since otherwise the function
1484 would use the "target pointer" return mechanism. */
1486 if (operation_type != TREE_TYPE (ret_val))
1487 ret_val = convert (operation_type, ret_val);
1490 = build2 (MODIFY_EXPR, operation_type, result_decl, ret_val);
1493 result_expr = NULL_TREE;
1495 return build1 (RETURN_EXPR, void_type_node, result_expr);
1498 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1502 build_call_1_expr (tree fundecl, tree arg)
1504 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1505 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1507 TREE_SIDE_EFFECTS (call) = 1;
1511 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1515 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1517 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1518 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1520 TREE_SIDE_EFFECTS (call) = 1;
1524 /* Likewise to call FUNDECL with no arguments. */
1527 build_call_0_expr (tree fundecl)
1529 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1530 it possible to propagate DECL_IS_PURE on parameterless functions. */
1531 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1532 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1537 /* Call a function that raises an exception and pass the line number and file
1538 name, if requested. MSG says which exception function to call.
1540 GNAT_NODE is the gnat node conveying the source location for which the
1541 error should be signaled, or Empty in which case the error is signaled on
1542 the current ref_file_name/input_line.
1544 KIND says which kind of exception this is for
1545 (N_Raise_{Constraint,Storage,Program}_Error). */
1548 build_call_raise (int msg, Node_Id gnat_node, char kind)
1550 tree fndecl = gnat_raise_decls[msg];
1551 tree label = get_exception_label (kind);
1557 /* If this is to be done as a goto, handle that case. */
1560 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1561 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1563 /* If Local_Raise is present, generate
1564 Local_Raise (exception'Identity); */
1565 if (Present (local_raise))
1567 tree gnu_local_raise
1568 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1569 tree gnu_exception_entity
1570 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1572 = build_call_1_expr (gnu_local_raise,
1573 build_unary_op (ADDR_EXPR, NULL_TREE,
1574 gnu_exception_entity));
1576 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1577 gnu_call, gnu_result);}
1583 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1585 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1586 ? IDENTIFIER_POINTER
1587 (get_identifier (Get_Name_String
1589 (Get_Source_File_Index (Sloc (gnat_node))))))
1592 len = strlen (str) + 1;
1593 filename = build_string (len, str);
1595 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1596 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1598 TREE_TYPE (filename)
1599 = build_array_type (char_type_node,
1600 build_index_type (build_int_cst (NULL_TREE, len)));
1603 build_call_2_expr (fndecl,
1604 build1 (ADDR_EXPR, build_pointer_type (char_type_node),
1606 build_int_cst (NULL_TREE, line_number));
1609 /* qsort comparer for the bit positions of two constructor elements
1610 for record components. */
1613 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1615 const_tree const elmt1 = * (const_tree const *) rt1;
1616 const_tree const elmt2 = * (const_tree const *) rt2;
1617 const_tree const field1 = TREE_PURPOSE (elmt1);
1618 const_tree const field2 = TREE_PURPOSE (elmt2);
1620 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1622 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1625 /* Return a CONSTRUCTOR of TYPE whose list is LIST. */
1628 gnat_build_constructor (tree type, tree list)
1632 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1633 bool side_effects = false;
1636 /* Scan the elements to see if they are all constant or if any has side
1637 effects, to let us set global flags on the resulting constructor. Count
1638 the elements along the way for possible sorting purposes below. */
1639 for (n_elmts = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), n_elmts ++)
1641 if (!TREE_CONSTANT (TREE_VALUE (elmt))
1642 || (TREE_CODE (type) == RECORD_TYPE
1643 && DECL_BIT_FIELD (TREE_PURPOSE (elmt))
1644 && TREE_CODE (TREE_VALUE (elmt)) != INTEGER_CST)
1645 || !initializer_constant_valid_p (TREE_VALUE (elmt),
1646 TREE_TYPE (TREE_VALUE (elmt))))
1647 allconstant = false;
1649 if (TREE_SIDE_EFFECTS (TREE_VALUE (elmt)))
1650 side_effects = true;
1652 /* Propagate an NULL_EXPR from the size of the type. We won't ever
1653 be executing the code we generate here in that case, but handle it
1654 specially to avoid the compiler blowing up. */
1655 if (TREE_CODE (type) == RECORD_TYPE
1657 = contains_null_expr (DECL_SIZE (TREE_PURPOSE (elmt))))))
1658 return build1 (NULL_EXPR, type, TREE_OPERAND (result, 0));
1661 /* For record types with constant components only, sort field list
1662 by increasing bit position. This is necessary to ensure the
1663 constructor can be output as static data. */
1664 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1666 /* Fill an array with an element tree per index, and ask qsort to order
1667 them according to what a bitpos comparison function says. */
1668 tree *gnu_arr = (tree *) alloca (sizeof (tree) * n_elmts);
1671 for (i = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), i++)
1674 qsort (gnu_arr, n_elmts, sizeof (tree), compare_elmt_bitpos);
1676 /* Then reconstruct the list from the sorted array contents. */
1678 for (i = n_elmts - 1; i >= 0; i--)
1680 TREE_CHAIN (gnu_arr[i]) = list;
1685 result = build_constructor_from_list (type, list);
1686 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1687 TREE_SIDE_EFFECTS (result) = side_effects;
1688 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1692 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1693 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1694 for the field. Don't fold the result if NO_FOLD_P is true.
1696 We also handle the fact that we might have been passed a pointer to the
1697 actual record and know how to look for fields in variant parts. */
1700 build_simple_component_ref (tree record_variable, tree component,
1701 tree field, bool no_fold_p)
1703 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1704 tree ref, inner_variable;
1706 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1707 || TREE_CODE (record_type) == UNION_TYPE
1708 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1709 && TYPE_SIZE (record_type)
1710 && (component != 0) != (field != 0));
1712 /* If no field was specified, look for a field with the specified name
1713 in the current record only. */
1715 for (field = TYPE_FIELDS (record_type); field;
1716 field = TREE_CHAIN (field))
1717 if (DECL_NAME (field) == component)
1723 /* If this field is not in the specified record, see if we can find
1724 something in the record whose original field is the same as this one. */
1725 if (DECL_CONTEXT (field) != record_type)
1726 /* Check if there is a field with name COMPONENT in the record. */
1730 /* First loop thru normal components. */
1732 for (new_field = TYPE_FIELDS (record_type); new_field;
1733 new_field = TREE_CHAIN (new_field))
1734 if (field == new_field
1735 || DECL_ORIGINAL_FIELD (new_field) == field
1736 || new_field == DECL_ORIGINAL_FIELD (field)
1737 || (DECL_ORIGINAL_FIELD (field)
1738 && (DECL_ORIGINAL_FIELD (field)
1739 == DECL_ORIGINAL_FIELD (new_field))))
1742 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1743 the component in the first search. Doing this search in 2 steps
1744 is required to avoiding hidden homonymous fields in the
1748 for (new_field = TYPE_FIELDS (record_type); new_field;
1749 new_field = TREE_CHAIN (new_field))
1750 if (DECL_INTERNAL_P (new_field))
1753 = build_simple_component_ref (record_variable,
1754 NULL_TREE, new_field, no_fold_p);
1755 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1768 /* If the field's offset has overflowed, do not attempt to access it
1769 as doing so may trigger sanity checks deeper in the back-end.
1770 Note that we don't need to warn since this will be done on trying
1771 to declare the object. */
1772 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1773 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1776 /* Look through conversion between type variants. Note that this
1777 is transparent as far as the field is concerned. */
1778 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1779 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1781 inner_variable = TREE_OPERAND (record_variable, 0);
1783 inner_variable = record_variable;
1785 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1788 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1789 TREE_READONLY (ref) = 1;
1790 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1791 || TYPE_VOLATILE (record_type))
1792 TREE_THIS_VOLATILE (ref) = 1;
1797 /* The generic folder may punt in this case because the inner array type
1798 can be self-referential, but folding is in fact not problematic. */
1799 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1800 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1802 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1803 unsigned HOST_WIDE_INT idx;
1805 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1815 /* Like build_simple_component_ref, except that we give an error if the
1816 reference could not be found. */
1819 build_component_ref (tree record_variable, tree component,
1820 tree field, bool no_fold_p)
1822 tree ref = build_simple_component_ref (record_variable, component, field,
1828 /* If FIELD was specified, assume this is an invalid user field so
1829 raise constraint error. Otherwise, we can't find the type to return, so
1832 return build1 (NULL_EXPR, TREE_TYPE (field),
1833 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1834 N_Raise_Constraint_Error));
1837 /* Build a GCC tree to call an allocation or deallocation function.
1838 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
1839 generate an allocator.
1841 GNU_SIZE is the size of the object in bytes and ALIGN is the alignment in
1842 bits. GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the
1843 storage pool to use. If not preset, malloc and free will be used except
1844 if GNAT_PROC is the "fake" value of -1, in which case we allocate the
1845 object dynamically on the stack frame. */
1848 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, unsigned align,
1849 Entity_Id gnat_proc, Entity_Id gnat_pool,
1852 tree gnu_align = size_int (align / BITS_PER_UNIT);
1854 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
1856 if (Present (gnat_proc))
1858 /* The storage pools are obviously always tagged types, but the
1859 secondary stack uses the same mechanism and is not tagged */
1860 if (Is_Tagged_Type (Etype (gnat_pool)))
1862 /* The size is the third parameter; the alignment is the
1864 Entity_Id gnat_size_type
1865 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1866 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1867 tree gnu_proc = gnat_to_gnu (gnat_proc);
1868 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1869 tree gnu_pool = gnat_to_gnu (gnat_pool);
1870 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1873 gnu_size = convert (gnu_size_type, gnu_size);
1874 gnu_align = convert (gnu_size_type, gnu_align);
1876 /* The first arg is always the address of the storage pool; next
1877 comes the address of the object, for a deallocator, then the
1878 size and alignment. */
1880 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1881 gnu_proc_addr, 4, gnu_pool_addr,
1882 gnu_obj, gnu_size, gnu_align);
1884 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1885 gnu_proc_addr, 3, gnu_pool_addr,
1886 gnu_size, gnu_align);
1887 TREE_SIDE_EFFECTS (gnu_call) = 1;
1891 /* Secondary stack case. */
1894 /* The size is the second parameter */
1895 Entity_Id gnat_size_type
1896 = Etype (Next_Formal (First_Formal (gnat_proc)));
1897 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1898 tree gnu_proc = gnat_to_gnu (gnat_proc);
1899 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1902 gnu_size = convert (gnu_size_type, gnu_size);
1904 /* The first arg is the address of the object, for a
1905 deallocator, then the size */
1907 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1908 gnu_proc_addr, 2, gnu_obj, gnu_size);
1910 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1911 gnu_proc_addr, 1, gnu_size);
1912 TREE_SIDE_EFFECTS (gnu_call) = 1;
1918 return build_call_1_expr (free_decl, gnu_obj);
1920 /* ??? For now, disable variable-sized allocators in the stack since
1921 we can't yet gimplify an ALLOCATE_EXPR. */
1922 else if (gnat_pool == -1
1923 && TREE_CODE (gnu_size) == INTEGER_CST && !flag_stack_check)
1925 /* If the size is a constant, we can put it in the fixed portion of
1926 the stack frame to avoid the need to adjust the stack pointer. */
1927 if (TREE_CODE (gnu_size) == INTEGER_CST && !flag_stack_check)
1930 = build_range_type (NULL_TREE, size_one_node, gnu_size);
1931 tree gnu_array_type = build_array_type (char_type_node, gnu_range);
1933 = create_var_decl (get_identifier ("RETVAL"), NULL_TREE,
1934 gnu_array_type, NULL_TREE, false, false, false,
1935 false, NULL, gnat_node);
1937 return convert (ptr_void_type_node,
1938 build_unary_op (ADDR_EXPR, NULL_TREE, gnu_decl));
1943 return build2 (ALLOCATE_EXPR, ptr_void_type_node, gnu_size, gnu_align);
1948 if (Nkind (gnat_node) != N_Allocator || !Comes_From_Source (gnat_node))
1949 Check_No_Implicit_Heap_Alloc (gnat_node);
1951 /* If the allocator size is 32bits but the pointer size is 64bits then
1952 allocate 32bit memory (sometimes necessary on 64bit VMS). Otherwise
1953 default to standard malloc. */
1954 if (TARGET_ABI_OPEN_VMS &&
1955 (!TARGET_MALLOC64 ||
1957 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1958 || Convention (Etype (gnat_node)) == Convention_C))))
1959 return build_call_1_expr (malloc32_decl, gnu_size);
1961 return build_call_1_expr (malloc_decl, gnu_size);
1965 /* Build a GCC tree to correspond to allocating an object of TYPE whose
1966 initial value is INIT, if INIT is nonzero. Convert the expression to
1967 RESULT_TYPE, which must be some type of pointer. Return the tree.
1968 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
1969 the storage pool to use. GNAT_NODE is used to provide an error
1970 location for restriction violations messages. If IGNORE_INIT_TYPE is
1971 true, ignore the type of INIT for the purpose of determining the size;
1972 this will cause the maximum size to be allocated if TYPE is of
1973 self-referential size. */
1976 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
1977 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
1979 tree size = TYPE_SIZE_UNIT (type);
1981 unsigned int default_allocator_alignment
1982 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1984 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
1985 if (init && TREE_CODE (init) == NULL_EXPR)
1986 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
1988 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
1989 sizes of the object and its template. Allocate the whole thing and
1990 fill in the parts that are known. */
1991 else if (TYPE_FAT_OR_THIN_POINTER_P (result_type))
1994 = build_unc_object_type_from_ptr (result_type, type,
1995 get_identifier ("ALLOC"));
1996 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
1997 tree storage_ptr_type = build_pointer_type (storage_type);
1999 tree template_cons = NULL_TREE;
2001 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2004 /* If the size overflows, pass -1 so the allocator will raise
2006 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2007 size = ssize_int (-1);
2009 storage = build_call_alloc_dealloc (NULL_TREE, size,
2010 TYPE_ALIGN (storage_type),
2011 gnat_proc, gnat_pool, gnat_node);
2012 storage = convert (storage_ptr_type, protect_multiple_eval (storage));
2014 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
2016 type = TREE_TYPE (TYPE_FIELDS (type));
2019 init = convert (type, init);
2022 /* If there is an initializing expression, make a constructor for
2023 the entire object including the bounds and copy it into the
2024 object. If there is no initializing expression, just set the
2028 template_cons = tree_cons (TREE_CHAIN (TYPE_FIELDS (storage_type)),
2030 template_cons = tree_cons (TYPE_FIELDS (storage_type),
2031 build_template (template_type, type,
2037 build2 (COMPOUND_EXPR, storage_ptr_type,
2039 (MODIFY_EXPR, storage_type,
2040 build_unary_op (INDIRECT_REF, NULL_TREE,
2041 convert (storage_ptr_type, storage)),
2042 gnat_build_constructor (storage_type, template_cons)),
2043 convert (storage_ptr_type, storage)));
2047 (COMPOUND_EXPR, result_type,
2049 (MODIFY_EXPR, template_type,
2051 (build_unary_op (INDIRECT_REF, NULL_TREE,
2052 convert (storage_ptr_type, storage)),
2053 NULL_TREE, TYPE_FIELDS (storage_type), 0),
2054 build_template (template_type, type, NULL_TREE)),
2055 convert (result_type, convert (storage_ptr_type, storage)));
2058 /* If we have an initializing expression, see if its size is simpler
2059 than the size from the type. */
2060 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2061 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2062 || CONTAINS_PLACEHOLDER_P (size)))
2063 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2065 /* If the size is still self-referential, reference the initializing
2066 expression, if it is present. If not, this must have been a
2067 call to allocate a library-level object, in which case we use
2068 the maximum size. */
2069 if (CONTAINS_PLACEHOLDER_P (size))
2071 if (!ignore_init_type && init)
2072 size = substitute_placeholder_in_expr (size, init);
2074 size = max_size (size, true);
2077 /* If the size overflows, pass -1 so the allocator will raise
2079 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2080 size = ssize_int (-1);
2082 /* If this is in the default storage pool and the type alignment is larger
2083 than what the default allocator supports, make an "aligning" record type
2084 with room to store a pointer before the field, allocate an object of that
2085 type, store the system's allocator return value just in front of the
2086 field and return the field's address. */
2088 if (No (gnat_proc) && TYPE_ALIGN (type) > default_allocator_alignment)
2090 /* Construct the aligning type with enough room for a pointer ahead
2091 of the field, then allocate. */
2093 = make_aligning_type (type, TYPE_ALIGN (type), size,
2094 default_allocator_alignment,
2095 POINTER_SIZE / BITS_PER_UNIT);
2097 tree record, record_addr;
2100 = build_call_alloc_dealloc (NULL_TREE, TYPE_SIZE_UNIT (record_type),
2101 default_allocator_alignment, Empty, Empty,
2105 = convert (build_pointer_type (record_type),
2106 save_expr (record_addr));
2108 record = build_unary_op (INDIRECT_REF, NULL_TREE, record_addr);
2110 /* Our RESULT (the Ada allocator's value) is the super-aligned address
2111 of the internal record field ... */
2113 = build_unary_op (ADDR_EXPR, NULL_TREE,
2115 (record, NULL_TREE, TYPE_FIELDS (record_type), 0));
2116 result = convert (result_type, result);
2118 /* ... with the system allocator's return value stored just in
2122 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
2123 convert (ptr_void_type_node, result),
2124 size_int (-POINTER_SIZE/BITS_PER_UNIT));
2127 = convert (build_pointer_type (ptr_void_type_node), ptr_addr);
2130 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2131 build_binary_op (MODIFY_EXPR, NULL_TREE,
2132 build_unary_op (INDIRECT_REF, NULL_TREE,
2134 convert (ptr_void_type_node,
2140 result = convert (result_type,
2141 build_call_alloc_dealloc (NULL_TREE, size,
2147 /* If we have an initial value, put the new address into a SAVE_EXPR, assign
2148 the value, and return the address. Do this with a COMPOUND_EXPR. */
2152 result = save_expr (result);
2154 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2156 (MODIFY_EXPR, NULL_TREE,
2157 build_unary_op (INDIRECT_REF,
2158 TREE_TYPE (TREE_TYPE (result)), result),
2163 return convert (result_type, result);
2166 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2167 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2168 how we derive the source location to raise C_E on an out of range
2172 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2175 tree parm_decl = get_gnu_tree (gnat_formal);
2176 tree const_list = NULL_TREE;
2177 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2178 int do_range_check =
2180 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2182 expr = maybe_unconstrained_array (expr);
2183 gnat_mark_addressable (expr);
2185 for (field = TYPE_FIELDS (record_type); field; field = TREE_CHAIN (field))
2187 tree conexpr = convert (TREE_TYPE (field),
2188 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2189 (DECL_INITIAL (field), expr));
2191 /* Check to ensure that only 32bit pointers are passed in
2192 32bit descriptors */
2193 if (do_range_check &&
2194 strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2196 tree pointer64type =
2197 build_pointer_type_for_mode (void_type_node, DImode, false);
2198 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2200 build_int_cstu (long_integer_type_node, 0x80000000);
2202 add_stmt (build3 (COND_EXPR, void_type_node,
2203 build_binary_op (GE_EXPR, long_integer_type_node,
2204 convert (long_integer_type_node,
2207 build_call_raise (CE_Range_Check_Failed, gnat_actual,
2208 N_Raise_Constraint_Error),
2211 const_list = tree_cons (field, conexpr, const_list);
2214 return gnat_build_constructor (record_type, nreverse (const_list));
2217 /* Indicate that we need to make the address of EXPR_NODE and it therefore
2218 should not be allocated in a register. Returns true if successful. */
2221 gnat_mark_addressable (tree expr_node)
2224 switch (TREE_CODE (expr_node))
2229 case ARRAY_RANGE_REF:
2232 case VIEW_CONVERT_EXPR:
2233 case NON_LVALUE_EXPR:
2235 expr_node = TREE_OPERAND (expr_node, 0);
2239 TREE_ADDRESSABLE (expr_node) = 1;
2245 TREE_ADDRESSABLE (expr_node) = 1;
2249 TREE_ADDRESSABLE (expr_node) = 1;
2253 return (DECL_CONST_CORRESPONDING_VAR (expr_node)
2254 && (gnat_mark_addressable
2255 (DECL_CONST_CORRESPONDING_VAR (expr_node))));