1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2009, 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 prevent
806 unneeded sign conversions when sizetype is wider than integer. */
807 right_operand = convert (right_base_type, right_operand);
808 right_operand = convert (sizetype, right_operand);
810 if (!TREE_CONSTANT (right_operand)
811 || !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
812 gnat_mark_addressable (left_operand);
821 gcc_assert (!POINTER_TYPE_P (left_type));
823 /* ... fall through ... */
827 /* If either operand is a NULL_EXPR, just return a new one. */
828 if (TREE_CODE (left_operand) == NULL_EXPR)
829 return build2 (op_code, result_type,
830 build1 (NULL_EXPR, integer_type_node,
831 TREE_OPERAND (left_operand, 0)),
834 else if (TREE_CODE (right_operand) == NULL_EXPR)
835 return build2 (op_code, result_type,
836 build1 (NULL_EXPR, integer_type_node,
837 TREE_OPERAND (right_operand, 0)),
840 /* If either object is a justified modular types, get the
841 fields from within. */
842 if (TREE_CODE (left_type) == RECORD_TYPE
843 && TYPE_JUSTIFIED_MODULAR_P (left_type))
845 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
847 left_type = TREE_TYPE (left_operand);
848 left_base_type = get_base_type (left_type);
851 if (TREE_CODE (right_type) == RECORD_TYPE
852 && TYPE_JUSTIFIED_MODULAR_P (right_type))
854 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
856 right_type = TREE_TYPE (right_operand);
857 right_base_type = get_base_type (right_type);
860 /* If both objects are arrays, compare them specially. */
861 if ((TREE_CODE (left_type) == ARRAY_TYPE
862 || (TREE_CODE (left_type) == INTEGER_TYPE
863 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
864 && (TREE_CODE (right_type) == ARRAY_TYPE
865 || (TREE_CODE (right_type) == INTEGER_TYPE
866 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
868 result = compare_arrays (result_type, left_operand, right_operand);
870 if (op_code == NE_EXPR)
871 result = invert_truthvalue (result);
873 gcc_assert (op_code == EQ_EXPR);
878 /* Otherwise, the base types must be the same unless the objects are
879 fat pointers or records. If we have records, use the best type and
880 convert both operands to that type. */
881 if (left_base_type != right_base_type)
883 if (TYPE_FAT_POINTER_P (left_base_type)
884 && TYPE_FAT_POINTER_P (right_base_type)
885 && TYPE_MAIN_VARIANT (left_base_type)
886 == TYPE_MAIN_VARIANT (right_base_type))
887 best_type = left_base_type;
888 else if (TREE_CODE (left_base_type) == RECORD_TYPE
889 && TREE_CODE (right_base_type) == RECORD_TYPE)
891 /* The only way these are permitted to be the same is if both
892 types have the same name. In that case, one of them must
893 not be self-referential. Use that one as the best type.
894 Even better is if one is of fixed size. */
895 gcc_assert (TYPE_NAME (left_base_type)
896 && (TYPE_NAME (left_base_type)
897 == TYPE_NAME (right_base_type)));
899 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
900 best_type = left_base_type;
901 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
902 best_type = right_base_type;
903 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
904 best_type = left_base_type;
905 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
906 best_type = right_base_type;
913 left_operand = convert (best_type, left_operand);
914 right_operand = convert (best_type, right_operand);
917 /* If we are comparing a fat pointer against zero, we need to
918 just compare the data pointer. */
919 else if (TYPE_FAT_POINTER_P (left_base_type)
920 && TREE_CODE (right_operand) == CONSTRUCTOR
921 && integer_zerop (VEC_index (constructor_elt,
922 CONSTRUCTOR_ELTS (right_operand),
926 right_operand = build_component_ref (left_operand, NULL_TREE,
927 TYPE_FIELDS (left_base_type),
929 left_operand = convert (TREE_TYPE (right_operand),
934 left_operand = convert (left_base_type, left_operand);
935 right_operand = convert (right_base_type, right_operand);
941 case PREINCREMENT_EXPR:
942 case PREDECREMENT_EXPR:
943 case POSTINCREMENT_EXPR:
944 case POSTDECREMENT_EXPR:
945 /* These operations are not used anymore. */
952 /* The RHS of a shift can be any type. Also, ignore any modulus
953 (we used to abort, but this is needed for unchecked conversion
954 to modular types). Otherwise, processing is the same as normal. */
955 gcc_assert (operation_type == left_base_type);
957 left_operand = convert (operation_type, left_operand);
960 case TRUTH_ANDIF_EXPR:
961 case TRUTH_ORIF_EXPR:
965 left_operand = gnat_truthvalue_conversion (left_operand);
966 right_operand = gnat_truthvalue_conversion (right_operand);
972 /* For binary modulus, if the inputs are in range, so are the
974 if (modulus && integer_pow2p (modulus))
979 gcc_assert (TREE_TYPE (result_type) == left_base_type
980 && TREE_TYPE (result_type) == right_base_type);
981 left_operand = convert (left_base_type, left_operand);
982 right_operand = convert (right_base_type, right_operand);
985 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
986 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
987 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
988 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
989 /* These always produce results lower than either operand. */
993 case POINTER_PLUS_EXPR:
994 gcc_assert (operation_type == left_base_type
995 && sizetype == right_base_type);
996 left_operand = convert (operation_type, left_operand);
997 right_operand = convert (sizetype, right_operand);
1000 case PLUS_NOMOD_EXPR:
1001 case MINUS_NOMOD_EXPR:
1002 if (op_code == PLUS_NOMOD_EXPR)
1003 op_code = PLUS_EXPR;
1005 op_code = MINUS_EXPR;
1006 modulus = NULL_TREE;
1008 /* ... fall through ... */
1012 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
1013 other compilers. Contrary to C, Ada doesn't allow arithmetics in
1014 these types but can generate addition/subtraction for Succ/Pred. */
1016 && (TREE_CODE (operation_type) == ENUMERAL_TYPE
1017 || TREE_CODE (operation_type) == BOOLEAN_TYPE))
1018 operation_type = left_base_type = right_base_type
1019 = gnat_type_for_mode (TYPE_MODE (operation_type),
1020 TYPE_UNSIGNED (operation_type));
1022 /* ... fall through ... */
1026 /* The result type should be the same as the base types of the
1027 both operands (and they should be the same). Convert
1028 everything to the result type. */
1030 gcc_assert (operation_type == left_base_type
1031 && left_base_type == right_base_type);
1032 left_operand = convert (operation_type, left_operand);
1033 right_operand = convert (operation_type, right_operand);
1036 if (modulus && !integer_pow2p (modulus))
1038 result = nonbinary_modular_operation (op_code, operation_type,
1039 left_operand, right_operand);
1040 modulus = NULL_TREE;
1042 /* If either operand is a NULL_EXPR, just return a new one. */
1043 else if (TREE_CODE (left_operand) == NULL_EXPR)
1044 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
1045 else if (TREE_CODE (right_operand) == NULL_EXPR)
1046 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
1047 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
1048 result = fold (build4 (op_code, operation_type, left_operand,
1049 right_operand, NULL_TREE, NULL_TREE));
1052 = fold_build2 (op_code, operation_type, left_operand, right_operand);
1054 TREE_SIDE_EFFECTS (result) |= has_side_effects;
1055 TREE_CONSTANT (result)
1056 |= (TREE_CONSTANT (left_operand) & TREE_CONSTANT (right_operand)
1057 && op_code != ARRAY_REF && op_code != ARRAY_RANGE_REF);
1059 if ((op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
1060 && TYPE_VOLATILE (operation_type))
1061 TREE_THIS_VOLATILE (result) = 1;
1063 /* If we are working with modular types, perform the MOD operation
1064 if something above hasn't eliminated the need for it. */
1066 result = fold_build2 (FLOOR_MOD_EXPR, operation_type, result,
1067 convert (operation_type, modulus));
1069 if (result_type && result_type != operation_type)
1070 result = convert (result_type, result);
1075 /* Similar, but for unary operations. */
1078 build_unary_op (enum tree_code op_code, tree result_type, tree operand)
1080 tree type = TREE_TYPE (operand);
1081 tree base_type = get_base_type (type);
1082 tree operation_type = result_type;
1084 bool side_effects = false;
1087 && TREE_CODE (operation_type) == RECORD_TYPE
1088 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
1089 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
1092 && !AGGREGATE_TYPE_P (operation_type)
1093 && TYPE_EXTRA_SUBTYPE_P (operation_type))
1094 operation_type = get_base_type (operation_type);
1100 if (!operation_type)
1101 result_type = operation_type = TREE_TYPE (type);
1103 gcc_assert (result_type == TREE_TYPE (type));
1105 result = fold_build1 (op_code, operation_type, operand);
1108 case TRUTH_NOT_EXPR:
1109 gcc_assert (result_type == base_type);
1110 result = invert_truthvalue (gnat_truthvalue_conversion (operand));
1113 case ATTR_ADDR_EXPR:
1115 switch (TREE_CODE (operand))
1118 case UNCONSTRAINED_ARRAY_REF:
1119 result = TREE_OPERAND (operand, 0);
1121 /* Make sure the type here is a pointer, not a reference.
1122 GCC wants pointer types for function addresses. */
1124 result_type = build_pointer_type (type);
1126 /* If the underlying object can alias everything, propagate the
1127 property since we are effectively retrieving the object. */
1128 if (POINTER_TYPE_P (TREE_TYPE (result))
1129 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1131 if (TREE_CODE (result_type) == POINTER_TYPE
1132 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1134 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1135 TYPE_MODE (result_type),
1137 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1138 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1140 = build_reference_type_for_mode (TREE_TYPE (result_type),
1141 TYPE_MODE (result_type),
1148 TREE_TYPE (result) = type = build_pointer_type (type);
1152 case ARRAY_RANGE_REF:
1155 /* If this is for 'Address, find the address of the prefix and
1156 add the offset to the field. Otherwise, do this the normal
1158 if (op_code == ATTR_ADDR_EXPR)
1160 HOST_WIDE_INT bitsize;
1161 HOST_WIDE_INT bitpos;
1163 enum machine_mode mode;
1164 int unsignedp, volatilep;
1166 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1167 &mode, &unsignedp, &volatilep,
1170 /* If INNER is a padding type whose field has a self-referential
1171 size, convert to that inner type. We know the offset is zero
1172 and we need to have that type visible. */
1173 if (TREE_CODE (TREE_TYPE (inner)) == RECORD_TYPE
1174 && TYPE_IS_PADDING_P (TREE_TYPE (inner))
1175 && (CONTAINS_PLACEHOLDER_P
1176 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1177 (TREE_TYPE (inner)))))))
1178 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1181 /* Compute the offset as a byte offset from INNER. */
1183 offset = size_zero_node;
1185 if (bitpos % BITS_PER_UNIT != 0)
1187 ("taking address of object not aligned on storage unit?",
1190 offset = size_binop (PLUS_EXPR, offset,
1191 size_int (bitpos / BITS_PER_UNIT));
1193 /* Take the address of INNER, convert the offset to void *, and
1194 add then. It will later be converted to the desired result
1196 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1197 inner = convert (ptr_void_type_node, inner);
1198 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1200 result = convert (build_pointer_type (TREE_TYPE (operand)),
1207 /* If this is just a constructor for a padded record, we can
1208 just take the address of the single field and convert it to
1209 a pointer to our type. */
1210 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
1212 result = (VEC_index (constructor_elt,
1213 CONSTRUCTOR_ELTS (operand),
1217 result = convert (build_pointer_type (TREE_TYPE (operand)),
1218 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1225 if (AGGREGATE_TYPE_P (type)
1226 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1227 return build_unary_op (ADDR_EXPR, result_type,
1228 TREE_OPERAND (operand, 0));
1230 /* ... fallthru ... */
1232 case VIEW_CONVERT_EXPR:
1233 /* If this just a variant conversion or if the conversion doesn't
1234 change the mode, get the result type from this type and go down.
1235 This is needed for conversions of CONST_DECLs, to eventually get
1236 to the address of their CORRESPONDING_VARs. */
1237 if ((TYPE_MAIN_VARIANT (type)
1238 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1239 || (TYPE_MODE (type) != BLKmode
1240 && (TYPE_MODE (type)
1241 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1242 return build_unary_op (ADDR_EXPR,
1243 (result_type ? result_type
1244 : build_pointer_type (type)),
1245 TREE_OPERAND (operand, 0));
1249 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1251 /* ... fall through ... */
1256 /* If we are taking the address of a padded record whose field is
1257 contains a template, take the address of the template. */
1258 if (TREE_CODE (type) == RECORD_TYPE
1259 && TYPE_IS_PADDING_P (type)
1260 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1261 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1263 type = TREE_TYPE (TYPE_FIELDS (type));
1264 operand = convert (type, operand);
1267 if (type != error_mark_node)
1268 operation_type = build_pointer_type (type);
1270 gnat_mark_addressable (operand);
1271 result = fold_build1 (ADDR_EXPR, operation_type, operand);
1274 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1278 /* If we want to refer to an entire unconstrained array,
1279 make up an expression to do so. This will never survive to
1280 the backend. If TYPE is a thin pointer, first convert the
1281 operand to a fat pointer. */
1282 if (TYPE_THIN_POINTER_P (type)
1283 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1286 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1288 type = TREE_TYPE (operand);
1291 if (TYPE_FAT_POINTER_P (type))
1293 result = build1 (UNCONSTRAINED_ARRAY_REF,
1294 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1295 TREE_READONLY (result) = TREE_STATIC (result)
1296 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1298 else if (TREE_CODE (operand) == ADDR_EXPR)
1299 result = TREE_OPERAND (operand, 0);
1303 result = fold_build1 (op_code, TREE_TYPE (type), operand);
1304 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1308 = (!TYPE_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1314 tree modulus = ((operation_type
1315 && TREE_CODE (operation_type) == INTEGER_TYPE
1316 && TYPE_MODULAR_P (operation_type))
1317 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1318 int mod_pow2 = modulus && integer_pow2p (modulus);
1320 /* If this is a modular type, there are various possibilities
1321 depending on the operation and whether the modulus is a
1322 power of two or not. */
1326 gcc_assert (operation_type == base_type);
1327 operand = convert (operation_type, operand);
1329 /* The fastest in the negate case for binary modulus is
1330 the straightforward code; the TRUNC_MOD_EXPR below
1331 is an AND operation. */
1332 if (op_code == NEGATE_EXPR && mod_pow2)
1333 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1334 fold_build1 (NEGATE_EXPR, operation_type,
1338 /* For nonbinary negate case, return zero for zero operand,
1339 else return the modulus minus the operand. If the modulus
1340 is a power of two minus one, we can do the subtraction
1341 as an XOR since it is equivalent and faster on most machines. */
1342 else if (op_code == NEGATE_EXPR && !mod_pow2)
1344 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1346 convert (operation_type,
1347 integer_one_node))))
1348 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1351 result = fold_build2 (MINUS_EXPR, operation_type,
1354 result = fold_build3 (COND_EXPR, operation_type,
1355 fold_build2 (NE_EXPR,
1360 integer_zero_node)),
1365 /* For the NOT cases, we need a constant equal to
1366 the modulus minus one. For a binary modulus, we
1367 XOR against the constant and subtract the operand from
1368 that constant for nonbinary modulus. */
1370 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1371 convert (operation_type,
1375 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1378 result = fold_build2 (MINUS_EXPR, operation_type,
1386 /* ... fall through ... */
1389 gcc_assert (operation_type == base_type);
1390 result = fold_build1 (op_code, operation_type,
1391 convert (operation_type, operand));
1396 TREE_SIDE_EFFECTS (result) = 1;
1397 if (TREE_CODE (result) == INDIRECT_REF)
1398 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1401 if (result_type && TREE_TYPE (result) != result_type)
1402 result = convert (result_type, result);
1407 /* Similar, but for COND_EXPR. */
1410 build_cond_expr (tree result_type, tree condition_operand,
1411 tree true_operand, tree false_operand)
1413 bool addr_p = false;
1416 /* The front-end verified that result, true and false operands have
1417 same base 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 the operands
1422 and then dereference our result. */
1423 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1424 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1426 result_type = build_pointer_type (result_type);
1427 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1428 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 we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1436 in both arms, make sure it gets evaluated by moving it ahead of the
1437 conditional expression. This is necessary because it is evaluated
1438 in only one place at run time and would otherwise be uninitialized
1439 in one of the arms. */
1440 true_operand = skip_simple_arithmetic (true_operand);
1441 false_operand = skip_simple_arithmetic (false_operand);
1443 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1444 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1447 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1452 /* Similar, but for RETURN_EXPR. If RESULT_DECL is non-zero, build
1453 a RETURN_EXPR around the assignment of RET_VAL to RESULT_DECL.
1454 If RESULT_DECL is zero, build a bare RETURN_EXPR. */
1457 build_return_expr (tree result_decl, tree ret_val)
1463 /* The gimplifier explicitly enforces the following invariant:
1472 As a consequence, type-homogeneity dictates that we use the type
1473 of the RESULT_DECL as the operation type. */
1475 tree operation_type = TREE_TYPE (result_decl);
1477 /* Convert the right operand to the operation type. Note that
1478 it's the same transformation as in the MODIFY_EXPR case of
1479 build_binary_op with the additional guarantee that the type
1480 cannot involve a placeholder, since otherwise the function
1481 would use the "target pointer" return mechanism. */
1483 if (operation_type != TREE_TYPE (ret_val))
1484 ret_val = convert (operation_type, ret_val);
1487 = build2 (MODIFY_EXPR, operation_type, result_decl, ret_val);
1490 result_expr = NULL_TREE;
1492 return build1 (RETURN_EXPR, void_type_node, result_expr);
1495 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1499 build_call_1_expr (tree fundecl, tree arg)
1501 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1502 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1504 TREE_SIDE_EFFECTS (call) = 1;
1508 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1512 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1514 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1515 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1517 TREE_SIDE_EFFECTS (call) = 1;
1521 /* Likewise to call FUNDECL with no arguments. */
1524 build_call_0_expr (tree fundecl)
1526 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1527 it possible to propagate DECL_IS_PURE on parameterless functions. */
1528 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1529 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1534 /* Call a function that raises an exception and pass the line number and file
1535 name, if requested. MSG says which exception function to call.
1537 GNAT_NODE is the gnat node conveying the source location for which the
1538 error should be signaled, or Empty in which case the error is signaled on
1539 the current ref_file_name/input_line.
1541 KIND says which kind of exception this is for
1542 (N_Raise_{Constraint,Storage,Program}_Error). */
1545 build_call_raise (int msg, Node_Id gnat_node, char kind)
1547 tree fndecl = gnat_raise_decls[msg];
1548 tree label = get_exception_label (kind);
1554 /* If this is to be done as a goto, handle that case. */
1557 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1558 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1560 /* If Local_Raise is present, generate
1561 Local_Raise (exception'Identity); */
1562 if (Present (local_raise))
1564 tree gnu_local_raise
1565 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1566 tree gnu_exception_entity
1567 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1569 = build_call_1_expr (gnu_local_raise,
1570 build_unary_op (ADDR_EXPR, NULL_TREE,
1571 gnu_exception_entity));
1573 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1574 gnu_call, gnu_result);}
1580 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1582 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1583 ? IDENTIFIER_POINTER
1584 (get_identifier (Get_Name_String
1586 (Get_Source_File_Index (Sloc (gnat_node))))))
1590 filename = build_string (len, str);
1592 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1593 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1595 TREE_TYPE (filename)
1596 = build_array_type (char_type_node, build_index_type (size_int (len)));
1599 build_call_2_expr (fndecl,
1600 build1 (ADDR_EXPR, build_pointer_type (char_type_node),
1602 build_int_cst (NULL_TREE, line_number));
1605 /* qsort comparer for the bit positions of two constructor elements
1606 for record components. */
1609 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1611 const_tree const elmt1 = * (const_tree const *) rt1;
1612 const_tree const elmt2 = * (const_tree const *) rt2;
1613 const_tree const field1 = TREE_PURPOSE (elmt1);
1614 const_tree const field2 = TREE_PURPOSE (elmt2);
1616 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1618 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1621 /* Return a CONSTRUCTOR of TYPE whose list is LIST. */
1624 gnat_build_constructor (tree type, tree list)
1626 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1627 bool side_effects = false;
1631 /* Scan the elements to see if they are all constant or if any has side
1632 effects, to let us set global flags on the resulting constructor. Count
1633 the elements along the way for possible sorting purposes below. */
1634 for (n_elmts = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), n_elmts ++)
1636 tree obj = TREE_PURPOSE (elmt);
1637 tree val = TREE_VALUE (elmt);
1639 /* The predicate must be in keeping with output_constructor. */
1640 if (!TREE_CONSTANT (val)
1641 || (TREE_CODE (type) == RECORD_TYPE
1642 && CONSTRUCTOR_BITFIELD_P (obj)
1643 && !initializer_constant_valid_for_bitfield_p (val))
1644 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1645 allconstant = false;
1647 if (TREE_SIDE_EFFECTS (val))
1648 side_effects = true;
1650 /* Propagate an NULL_EXPR from the size of the type. We won't ever
1651 be executing the code we generate here in that case, but handle it
1652 specially to avoid the compiler blowing up. */
1653 if (TREE_CODE (type) == RECORD_TYPE
1654 && (result = contains_null_expr (DECL_SIZE (obj))) != NULL_TREE)
1655 return build1 (NULL_EXPR, type, TREE_OPERAND (result, 0));
1658 /* For record types with constant components only, sort field list
1659 by increasing bit position. This is necessary to ensure the
1660 constructor can be output as static data. */
1661 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1663 /* Fill an array with an element tree per index, and ask qsort to order
1664 them according to what a bitpos comparison function says. */
1665 tree *gnu_arr = (tree *) alloca (sizeof (tree) * n_elmts);
1668 for (i = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), i++)
1671 qsort (gnu_arr, n_elmts, sizeof (tree), compare_elmt_bitpos);
1673 /* Then reconstruct the list from the sorted array contents. */
1675 for (i = n_elmts - 1; i >= 0; i--)
1677 TREE_CHAIN (gnu_arr[i]) = list;
1682 result = build_constructor_from_list (type, list);
1683 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1684 TREE_SIDE_EFFECTS (result) = side_effects;
1685 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1689 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1690 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1691 for the field. Don't fold the result if NO_FOLD_P is true.
1693 We also handle the fact that we might have been passed a pointer to the
1694 actual record and know how to look for fields in variant parts. */
1697 build_simple_component_ref (tree record_variable, tree component,
1698 tree field, bool no_fold_p)
1700 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1701 tree ref, inner_variable;
1703 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1704 || TREE_CODE (record_type) == UNION_TYPE
1705 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1706 && TYPE_SIZE (record_type)
1707 && (component != 0) != (field != 0));
1709 /* If no field was specified, look for a field with the specified name
1710 in the current record only. */
1712 for (field = TYPE_FIELDS (record_type); field;
1713 field = TREE_CHAIN (field))
1714 if (DECL_NAME (field) == component)
1720 /* If this field is not in the specified record, see if we can find
1721 something in the record whose original field is the same as this one. */
1722 if (DECL_CONTEXT (field) != record_type)
1723 /* Check if there is a field with name COMPONENT in the record. */
1727 /* First loop thru normal components. */
1729 for (new_field = TYPE_FIELDS (record_type); new_field;
1730 new_field = TREE_CHAIN (new_field))
1731 if (field == new_field
1732 || DECL_ORIGINAL_FIELD (new_field) == field
1733 || new_field == DECL_ORIGINAL_FIELD (field)
1734 || (DECL_ORIGINAL_FIELD (field)
1735 && (DECL_ORIGINAL_FIELD (field)
1736 == DECL_ORIGINAL_FIELD (new_field))))
1739 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1740 the component in the first search. Doing this search in 2 steps
1741 is required to avoiding hidden homonymous fields in the
1745 for (new_field = TYPE_FIELDS (record_type); new_field;
1746 new_field = TREE_CHAIN (new_field))
1747 if (DECL_INTERNAL_P (new_field))
1750 = build_simple_component_ref (record_variable,
1751 NULL_TREE, new_field, no_fold_p);
1752 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1765 /* If the field's offset has overflowed, do not attempt to access it
1766 as doing so may trigger sanity checks deeper in the back-end.
1767 Note that we don't need to warn since this will be done on trying
1768 to declare the object. */
1769 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1770 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1773 /* Look through conversion between type variants. Note that this
1774 is transparent as far as the field is concerned. */
1775 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1776 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1778 inner_variable = TREE_OPERAND (record_variable, 0);
1780 inner_variable = record_variable;
1782 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1785 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1786 TREE_READONLY (ref) = 1;
1787 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1788 || TYPE_VOLATILE (record_type))
1789 TREE_THIS_VOLATILE (ref) = 1;
1794 /* The generic folder may punt in this case because the inner array type
1795 can be self-referential, but folding is in fact not problematic. */
1796 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1797 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1799 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1800 unsigned HOST_WIDE_INT idx;
1802 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1812 /* Like build_simple_component_ref, except that we give an error if the
1813 reference could not be found. */
1816 build_component_ref (tree record_variable, tree component,
1817 tree field, bool no_fold_p)
1819 tree ref = build_simple_component_ref (record_variable, component, field,
1825 /* If FIELD was specified, assume this is an invalid user field so raise
1826 Constraint_Error. Otherwise, we have no type to return so abort. */
1828 return build1 (NULL_EXPR, TREE_TYPE (field),
1829 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1830 N_Raise_Constraint_Error));
1833 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1834 identically. Process the case where a GNAT_PROC to call is provided. */
1837 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1838 Entity_Id gnat_proc, Entity_Id gnat_pool)
1840 tree gnu_proc = gnat_to_gnu (gnat_proc);
1841 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1844 /* The storage pools are obviously always tagged types, but the
1845 secondary stack uses the same mechanism and is not tagged. */
1846 if (Is_Tagged_Type (Etype (gnat_pool)))
1848 /* The size is the third parameter; the alignment is the
1850 Entity_Id gnat_size_type
1851 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1852 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1854 tree gnu_pool = gnat_to_gnu (gnat_pool);
1855 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1856 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1858 gnu_size = convert (gnu_size_type, gnu_size);
1859 gnu_align = convert (gnu_size_type, gnu_align);
1861 /* The first arg is always the address of the storage pool; next
1862 comes the address of the object, for a deallocator, then the
1863 size and alignment. */
1865 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1866 gnu_proc_addr, 4, gnu_pool_addr,
1867 gnu_obj, gnu_size, gnu_align);
1869 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1870 gnu_proc_addr, 3, gnu_pool_addr,
1871 gnu_size, gnu_align);
1874 /* Secondary stack case. */
1877 /* The size is the second parameter. */
1878 Entity_Id gnat_size_type
1879 = Etype (Next_Formal (First_Formal (gnat_proc)));
1880 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1882 gnu_size = convert (gnu_size_type, gnu_size);
1884 /* The first arg is the address of the object, for a deallocator,
1887 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1888 gnu_proc_addr, 2, gnu_obj, gnu_size);
1890 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1891 gnu_proc_addr, 1, gnu_size);
1894 TREE_SIDE_EFFECTS (gnu_call) = 1;
1898 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1899 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1900 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1904 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1906 /* When the DATA_TYPE alignment is stricter than what malloc offers
1907 (super-aligned case), we allocate an "aligning" wrapper type and return
1908 the address of its single data field with the malloc's return value
1909 stored just in front. */
1911 unsigned int data_align = TYPE_ALIGN (data_type);
1912 unsigned int default_allocator_alignment
1913 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1916 = ((data_align > default_allocator_alignment)
1917 ? make_aligning_type (data_type, data_align, data_size,
1918 default_allocator_alignment,
1919 POINTER_SIZE / BITS_PER_UNIT)
1923 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1927 /* On VMS, if 64-bit memory is disabled or pointers are 64-bit and the
1928 allocator size is 32-bit or Convention C, allocate 32-bit memory. */
1929 if (TARGET_ABI_OPEN_VMS
1930 && (!TARGET_MALLOC64
1931 || (POINTER_SIZE == 64
1932 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1933 || Convention (Etype (gnat_node)) == Convention_C))))
1934 malloc_ptr = build_call_1_expr (malloc32_decl, size_to_malloc);
1936 malloc_ptr = build_call_1_expr (malloc_decl, size_to_malloc);
1940 /* Latch malloc's return value and get a pointer to the aligning field
1942 tree storage_ptr = save_expr (malloc_ptr);
1944 tree aligning_record_addr
1945 = convert (build_pointer_type (aligning_type), storage_ptr);
1947 tree aligning_record
1948 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1951 = build_component_ref (aligning_record, NULL_TREE,
1952 TYPE_FIELDS (aligning_type), 0);
1954 tree aligning_field_addr
1955 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1957 /* Then arrange to store the allocator's return value ahead
1959 tree storage_ptr_slot_addr
1960 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1961 convert (ptr_void_type_node, aligning_field_addr),
1962 size_int (-POINTER_SIZE/BITS_PER_UNIT));
1964 tree storage_ptr_slot
1965 = build_unary_op (INDIRECT_REF, NULL_TREE,
1966 convert (build_pointer_type (ptr_void_type_node),
1967 storage_ptr_slot_addr));
1970 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
1971 build_binary_op (MODIFY_EXPR, NULL_TREE,
1972 storage_ptr_slot, storage_ptr),
1973 aligning_field_addr);
1979 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
1980 designated by DATA_PTR using the __gnat_free entry point. */
1983 maybe_wrap_free (tree data_ptr, tree data_type)
1985 /* In the regular alignment case, we pass the data pointer straight to free.
1986 In the superaligned case, we need to retrieve the initial allocator
1987 return value, stored in front of the data block at allocation time. */
1989 unsigned int data_align = TYPE_ALIGN (data_type);
1990 unsigned int default_allocator_alignment
1991 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1995 if (data_align > default_allocator_alignment)
1997 /* DATA_FRONT_PTR (void *)
1998 = (void *)DATA_PTR - (void *)sizeof (void *)) */
2001 (POINTER_PLUS_EXPR, ptr_void_type_node,
2002 convert (ptr_void_type_node, data_ptr),
2003 size_int (-POINTER_SIZE/BITS_PER_UNIT));
2005 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
2008 (INDIRECT_REF, NULL_TREE,
2009 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
2012 free_ptr = data_ptr;
2014 return build_call_1_expr (free_decl, free_ptr);
2017 /* Build a GCC tree to call an allocation or deallocation function.
2018 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
2019 generate an allocator.
2021 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
2022 object type, used to determine the to-be-honored address alignment.
2023 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
2024 pool to use. If not present, malloc and free are used. GNAT_NODE is used
2025 to provide an error location for restriction violation messages. */
2028 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
2029 Entity_Id gnat_proc, Entity_Id gnat_pool,
2032 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
2034 /* Explicit proc to call ? This one is assumed to deal with the type
2035 alignment constraints. */
2036 if (Present (gnat_proc))
2037 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
2038 gnat_proc, gnat_pool);
2040 /* Otherwise, object to "free" or "malloc" with possible special processing
2041 for alignments stricter than what the default allocator honors. */
2043 return maybe_wrap_free (gnu_obj, gnu_type);
2046 /* Assert that we no longer can be called with this special pool. */
2047 gcc_assert (gnat_pool != -1);
2049 /* Check that we aren't violating the associated restriction. */
2050 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
2051 Check_No_Implicit_Heap_Alloc (gnat_node);
2053 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
2057 /* Build a GCC tree to correspond to allocating an object of TYPE whose
2058 initial value is INIT, if INIT is nonzero. Convert the expression to
2059 RESULT_TYPE, which must be some type of pointer. Return the tree.
2061 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
2062 the storage pool to use. GNAT_NODE is used to provide an error
2063 location for restriction violation messages. If IGNORE_INIT_TYPE is
2064 true, ignore the type of INIT for the purpose of determining the size;
2065 this will cause the maximum size to be allocated if TYPE is of
2066 self-referential size. */
2069 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
2070 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
2072 tree size = TYPE_SIZE_UNIT (type);
2075 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
2076 if (init && TREE_CODE (init) == NULL_EXPR)
2077 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
2079 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
2080 sizes of the object and its template. Allocate the whole thing and
2081 fill in the parts that are known. */
2082 else if (TYPE_FAT_OR_THIN_POINTER_P (result_type))
2085 = build_unc_object_type_from_ptr (result_type, type,
2086 get_identifier ("ALLOC"));
2087 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
2088 tree storage_ptr_type = build_pointer_type (storage_type);
2090 tree template_cons = NULL_TREE;
2092 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2095 /* If the size overflows, pass -1 so the allocator will raise
2097 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2098 size = ssize_int (-1);
2100 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2101 gnat_proc, gnat_pool, gnat_node);
2102 storage = convert (storage_ptr_type, protect_multiple_eval (storage));
2104 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
2106 type = TREE_TYPE (TYPE_FIELDS (type));
2109 init = convert (type, init);
2112 /* If there is an initializing expression, make a constructor for
2113 the entire object including the bounds and copy it into the
2114 object. If there is no initializing expression, just set the
2118 template_cons = tree_cons (TREE_CHAIN (TYPE_FIELDS (storage_type)),
2120 template_cons = tree_cons (TYPE_FIELDS (storage_type),
2121 build_template (template_type, type,
2127 build2 (COMPOUND_EXPR, storage_ptr_type,
2129 (MODIFY_EXPR, storage_type,
2130 build_unary_op (INDIRECT_REF, NULL_TREE,
2131 convert (storage_ptr_type, storage)),
2132 gnat_build_constructor (storage_type, template_cons)),
2133 convert (storage_ptr_type, storage)));
2137 (COMPOUND_EXPR, result_type,
2139 (MODIFY_EXPR, template_type,
2141 (build_unary_op (INDIRECT_REF, NULL_TREE,
2142 convert (storage_ptr_type, storage)),
2143 NULL_TREE, TYPE_FIELDS (storage_type), 0),
2144 build_template (template_type, type, NULL_TREE)),
2145 convert (result_type, convert (storage_ptr_type, storage)));
2148 /* If we have an initializing expression, see if its size is simpler
2149 than the size from the type. */
2150 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2151 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2152 || CONTAINS_PLACEHOLDER_P (size)))
2153 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2155 /* If the size is still self-referential, reference the initializing
2156 expression, if it is present. If not, this must have been a
2157 call to allocate a library-level object, in which case we use
2158 the maximum size. */
2159 if (CONTAINS_PLACEHOLDER_P (size))
2161 if (!ignore_init_type && init)
2162 size = substitute_placeholder_in_expr (size, init);
2164 size = max_size (size, true);
2167 /* If the size overflows, pass -1 so the allocator will raise
2169 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2170 size = ssize_int (-1);
2172 result = convert (result_type,
2173 build_call_alloc_dealloc (NULL_TREE, size, type,
2174 gnat_proc, gnat_pool,
2177 /* If we have an initial value, put the new address into a SAVE_EXPR, assign
2178 the value, and return the address. Do this with a COMPOUND_EXPR. */
2182 result = save_expr (result);
2184 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2186 (MODIFY_EXPR, NULL_TREE,
2187 build_unary_op (INDIRECT_REF,
2188 TREE_TYPE (TREE_TYPE (result)), result),
2193 return convert (result_type, result);
2196 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2197 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2198 how we derive the source location to raise C_E on an out of range
2202 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2205 tree parm_decl = get_gnu_tree (gnat_formal);
2206 tree const_list = NULL_TREE;
2207 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2208 int do_range_check =
2210 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2212 expr = maybe_unconstrained_array (expr);
2213 gnat_mark_addressable (expr);
2215 for (field = TYPE_FIELDS (record_type); field; field = TREE_CHAIN (field))
2217 tree conexpr = convert (TREE_TYPE (field),
2218 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2219 (DECL_INITIAL (field), expr));
2221 /* Check to ensure that only 32bit pointers are passed in
2222 32bit descriptors */
2223 if (do_range_check &&
2224 strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2226 tree pointer64type =
2227 build_pointer_type_for_mode (void_type_node, DImode, false);
2228 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2230 build_int_cstu (long_integer_type_node, 0x80000000);
2232 add_stmt (build3 (COND_EXPR, void_type_node,
2233 build_binary_op (GE_EXPR, long_integer_type_node,
2234 convert (long_integer_type_node,
2237 build_call_raise (CE_Range_Check_Failed, gnat_actual,
2238 N_Raise_Constraint_Error),
2241 const_list = tree_cons (field, conexpr, const_list);
2244 return gnat_build_constructor (record_type, nreverse (const_list));
2247 /* Indicate that we need to make the address of EXPR_NODE and it therefore
2248 should not be allocated in a register. Returns true if successful. */
2251 gnat_mark_addressable (tree expr_node)
2254 switch (TREE_CODE (expr_node))
2259 case ARRAY_RANGE_REF:
2262 case VIEW_CONVERT_EXPR:
2263 case NON_LVALUE_EXPR:
2265 expr_node = TREE_OPERAND (expr_node, 0);
2269 TREE_ADDRESSABLE (expr_node) = 1;
2275 TREE_ADDRESSABLE (expr_node) = 1;
2279 TREE_ADDRESSABLE (expr_node) = 1;
2283 return (DECL_CONST_CORRESPONDING_VAR (expr_node)
2284 && (gnat_mark_addressable
2285 (DECL_CONST_CORRESPONDING_VAR (expr_node))));