1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2010, 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"
34 #include "tree-inline.h"
51 /* Return the base type of TYPE. */
54 get_base_type (tree type)
56 if (TREE_CODE (type) == RECORD_TYPE
57 && TYPE_JUSTIFIED_MODULAR_P (type))
58 type = TREE_TYPE (TYPE_FIELDS (type));
60 while (TREE_TYPE (type)
61 && (TREE_CODE (type) == INTEGER_TYPE
62 || TREE_CODE (type) == REAL_TYPE))
63 type = TREE_TYPE (type);
68 /* EXP is a GCC tree representing an address. See if we can find how
69 strictly the object at that address is aligned. Return that alignment
70 in bits. If we don't know anything about the alignment, return 0. */
73 known_alignment (tree exp)
75 unsigned int this_alignment;
76 unsigned int lhs, rhs;
78 switch (TREE_CODE (exp))
81 case VIEW_CONVERT_EXPR:
83 /* Conversions between pointers and integers don't change the alignment
84 of the underlying object. */
85 this_alignment = known_alignment (TREE_OPERAND (exp, 0));
89 /* The value of a COMPOUND_EXPR is that of it's second operand. */
90 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
95 /* If two address are added, the alignment of the result is the
96 minimum of the two alignments. */
97 lhs = known_alignment (TREE_OPERAND (exp, 0));
98 rhs = known_alignment (TREE_OPERAND (exp, 1));
99 this_alignment = MIN (lhs, rhs);
102 case POINTER_PLUS_EXPR:
103 lhs = known_alignment (TREE_OPERAND (exp, 0));
104 rhs = known_alignment (TREE_OPERAND (exp, 1));
105 /* If we don't know the alignment of the offset, we assume that
108 this_alignment = lhs;
110 this_alignment = MIN (lhs, rhs);
114 /* If there is a choice between two values, use the smallest one. */
115 lhs = known_alignment (TREE_OPERAND (exp, 1));
116 rhs = known_alignment (TREE_OPERAND (exp, 2));
117 this_alignment = MIN (lhs, rhs);
122 unsigned HOST_WIDE_INT c = TREE_INT_CST_LOW (exp);
123 /* The first part of this represents the lowest bit in the constant,
124 but it is originally in bytes, not bits. */
125 this_alignment = MIN (BITS_PER_UNIT * (c & -c), BIGGEST_ALIGNMENT);
130 /* If we know the alignment of just one side, use it. Otherwise,
131 use the product of the alignments. */
132 lhs = known_alignment (TREE_OPERAND (exp, 0));
133 rhs = known_alignment (TREE_OPERAND (exp, 1));
136 this_alignment = rhs;
138 this_alignment = lhs;
140 this_alignment = MIN (lhs * rhs, BIGGEST_ALIGNMENT);
144 /* A bit-and expression is as aligned as the maximum alignment of the
145 operands. We typically get here for a complex lhs and a constant
146 negative power of two on the rhs to force an explicit alignment, so
147 don't bother looking at the lhs. */
148 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
152 this_alignment = expr_align (TREE_OPERAND (exp, 0));
157 tree t = maybe_inline_call_in_expr (exp);
159 return known_alignment (t);
162 /* Fall through... */
165 /* For other pointer expressions, we assume that the pointed-to object
166 is at least as aligned as the pointed-to type. Beware that we can
167 have a dummy type here (e.g. a Taft Amendment type), for which the
168 alignment is meaningless and should be ignored. */
169 if (POINTER_TYPE_P (TREE_TYPE (exp))
170 && !TYPE_IS_DUMMY_P (TREE_TYPE (TREE_TYPE (exp))))
171 this_alignment = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp)));
177 return this_alignment;
180 /* We have a comparison or assignment operation on two types, T1 and T2, which
181 are either both array types or both record types. T1 is assumed to be for
182 the left hand side operand, and T2 for the right hand side. Return the
183 type that both operands should be converted to for the operation, if any.
184 Otherwise return zero. */
187 find_common_type (tree t1, tree t2)
189 /* ??? As of today, various constructs lead here with types of different
190 sizes even when both constants (e.g. tagged types, packable vs regular
191 component types, padded vs unpadded types, ...). While some of these
192 would better be handled upstream (types should be made consistent before
193 calling into build_binary_op), some others are really expected and we
194 have to be careful. */
196 /* We must prevent writing more than what the target may hold if this is for
197 an assignment and the case of tagged types is handled in build_binary_op
198 so use the lhs type if it is known to be smaller, or of constant size and
199 the rhs type is not, whatever the modes. We also force t1 in case of
200 constant size equality to minimize occurrences of view conversions on the
201 lhs of assignments. */
202 if (TREE_CONSTANT (TYPE_SIZE (t1))
203 && (!TREE_CONSTANT (TYPE_SIZE (t2))
204 || !tree_int_cst_lt (TYPE_SIZE (t2), TYPE_SIZE (t1))))
207 /* Otherwise, if the lhs type is non-BLKmode, use it. Note that we know
208 that we will not have any alignment problems since, if we did, the
209 non-BLKmode type could not have been used. */
210 if (TYPE_MODE (t1) != BLKmode)
213 /* If the rhs type is of constant size, use it whatever the modes. At
214 this point it is known to be smaller, or of constant size and the
216 if (TREE_CONSTANT (TYPE_SIZE (t2)))
219 /* Otherwise, if the rhs type is non-BLKmode, use it. */
220 if (TYPE_MODE (t2) != BLKmode)
223 /* In this case, both types have variable size and BLKmode. It's
224 probably best to leave the "type mismatch" because changing it
225 could cause a bad self-referential reference. */
229 /* Return an expression tree representing an equality comparison of A1 and A2,
230 two objects of type ARRAY_TYPE. The result should be of type RESULT_TYPE.
232 Two arrays are equal in one of two ways: (1) if both have zero length in
233 some dimension (not necessarily the same dimension) or (2) if the lengths
234 in each dimension are equal and the data is equal. We perform the length
235 tests in as efficient a manner as possible. */
238 compare_arrays (location_t loc, tree result_type, tree a1, tree a2)
240 tree result = convert (result_type, boolean_true_node);
241 tree a1_is_null = convert (result_type, boolean_false_node);
242 tree a2_is_null = convert (result_type, boolean_false_node);
243 tree t1 = TREE_TYPE (a1);
244 tree t2 = TREE_TYPE (a2);
245 bool a1_side_effects_p = TREE_SIDE_EFFECTS (a1);
246 bool a2_side_effects_p = TREE_SIDE_EFFECTS (a2);
247 bool length_zero_p = false;
249 /* If either operand has side-effects, they have to be evaluated only once
250 in spite of the multiple references to the operand in the comparison. */
251 if (a1_side_effects_p)
252 a1 = gnat_protect_expr (a1);
254 if (a2_side_effects_p)
255 a2 = gnat_protect_expr (a2);
257 /* Process each dimension separately and compare the lengths. If any
258 dimension has a length known to be zero, set LENGTH_ZERO_P to true
259 in order to suppress the comparison of the data at the end. */
260 while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
262 tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
263 tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
264 tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
265 tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
266 tree length1 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub1, lb1),
268 tree length2 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub2, lb2),
270 tree comparison, this_a1_is_null, this_a2_is_null;
272 /* If the length of the first array is a constant, swap our operands
273 unless the length of the second array is the constant zero. */
274 if (TREE_CODE (length1) == INTEGER_CST && !integer_zerop (length2))
279 tem = a1, a1 = a2, a2 = tem;
280 tem = t1, t1 = t2, t2 = tem;
281 tem = lb1, lb1 = lb2, lb2 = tem;
282 tem = ub1, ub1 = ub2, ub2 = tem;
283 tem = length1, length1 = length2, length2 = tem;
284 tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
285 btem = a1_side_effects_p, a1_side_effects_p = a2_side_effects_p,
286 a2_side_effects_p = btem;
289 /* If the length of the second array is the constant zero, we can just
290 use the original stored bounds for the first array and see whether
291 last < first holds. */
292 if (integer_zerop (length2))
294 length_zero_p = true;
296 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
297 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
299 comparison = fold_build2_loc (loc, LT_EXPR, result_type, ub1, lb1);
300 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
301 if (EXPR_P (comparison))
302 SET_EXPR_LOCATION (comparison, loc);
304 this_a1_is_null = comparison;
305 this_a2_is_null = convert (result_type, boolean_true_node);
308 /* Otherwise, if the length is some other constant value, we know that
309 this dimension in the second array cannot be superflat, so we can
310 just use its length computed from the actual stored bounds. */
311 else if (TREE_CODE (length2) == INTEGER_CST)
315 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
316 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
317 /* Note that we know that UB2 and LB2 are constant and hence
318 cannot contain a PLACEHOLDER_EXPR. */
319 ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
320 lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
321 bt = get_base_type (TREE_TYPE (ub1));
324 = fold_build2_loc (loc, EQ_EXPR, result_type,
325 build_binary_op (MINUS_EXPR, bt, ub1, lb1),
326 build_binary_op (MINUS_EXPR, bt, ub2, lb2));
327 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
328 if (EXPR_P (comparison))
329 SET_EXPR_LOCATION (comparison, loc);
332 = fold_build2_loc (loc, LT_EXPR, result_type, ub1, lb1);
334 this_a2_is_null = convert (result_type, boolean_false_node);
337 /* Otherwise, compare the computed lengths. */
340 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
341 length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
344 = fold_build2_loc (loc, EQ_EXPR, result_type, length1, length2);
346 /* If the length expression is of the form (cond ? val : 0), assume
347 that cond is equivalent to (length != 0). That's guaranteed by
348 construction of the array types in gnat_to_gnu_entity. */
349 if (TREE_CODE (length1) == COND_EXPR
350 && integer_zerop (TREE_OPERAND (length1, 2)))
352 = invert_truthvalue_loc (loc, TREE_OPERAND (length1, 0));
354 this_a1_is_null = fold_build2_loc (loc, EQ_EXPR, result_type,
355 length1, size_zero_node);
357 /* Likewise for the second array. */
358 if (TREE_CODE (length2) == COND_EXPR
359 && integer_zerop (TREE_OPERAND (length2, 2)))
361 = invert_truthvalue_loc (loc, TREE_OPERAND (length2, 0));
363 this_a2_is_null = fold_build2_loc (loc, EQ_EXPR, result_type,
364 length2, size_zero_node);
367 /* Append expressions for this dimension to the final expressions. */
368 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
371 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
372 this_a1_is_null, a1_is_null);
374 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
375 this_a2_is_null, a2_is_null);
381 /* Unless the length of some dimension is known to be zero, compare the
382 data in the array. */
385 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
390 a1 = convert (type, a1),
391 a2 = convert (type, a2);
394 comparison = fold_build2_loc (loc, EQ_EXPR, result_type, a1, a2);
397 = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result, comparison);
400 /* The result is also true if both sizes are zero. */
401 result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
402 build_binary_op (TRUTH_ANDIF_EXPR, result_type,
403 a1_is_null, a2_is_null),
406 /* If either operand has side-effects, they have to be evaluated before
407 starting the comparison above since the place they would be otherwise
408 evaluated could be wrong. */
409 if (a1_side_effects_p)
410 result = build2 (COMPOUND_EXPR, result_type, a1, result);
412 if (a2_side_effects_p)
413 result = build2 (COMPOUND_EXPR, result_type, a2, result);
418 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
419 type TYPE. We know that TYPE is a modular type with a nonbinary
423 nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
426 tree modulus = TYPE_MODULUS (type);
427 unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
428 unsigned int precision;
429 bool unsignedp = true;
433 /* If this is an addition of a constant, convert it to a subtraction
434 of a constant since we can do that faster. */
435 if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
437 rhs = fold_build2 (MINUS_EXPR, type, modulus, rhs);
438 op_code = MINUS_EXPR;
441 /* For the logical operations, we only need PRECISION bits. For
442 addition and subtraction, we need one more and for multiplication we
443 need twice as many. But we never want to make a size smaller than
445 if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
446 needed_precision += 1;
447 else if (op_code == MULT_EXPR)
448 needed_precision *= 2;
450 precision = MAX (needed_precision, TYPE_PRECISION (op_type));
452 /* Unsigned will do for everything but subtraction. */
453 if (op_code == MINUS_EXPR)
456 /* If our type is the wrong signedness or isn't wide enough, make a new
457 type and convert both our operands to it. */
458 if (TYPE_PRECISION (op_type) < precision
459 || TYPE_UNSIGNED (op_type) != unsignedp)
461 /* Copy the node so we ensure it can be modified to make it modular. */
462 op_type = copy_node (gnat_type_for_size (precision, unsignedp));
463 modulus = convert (op_type, modulus);
464 SET_TYPE_MODULUS (op_type, modulus);
465 TYPE_MODULAR_P (op_type) = 1;
466 lhs = convert (op_type, lhs);
467 rhs = convert (op_type, rhs);
470 /* Do the operation, then we'll fix it up. */
471 result = fold_build2 (op_code, op_type, lhs, rhs);
473 /* For multiplication, we have no choice but to do a full modulus
474 operation. However, we want to do this in the narrowest
476 if (op_code == MULT_EXPR)
478 tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
479 modulus = convert (div_type, modulus);
480 SET_TYPE_MODULUS (div_type, modulus);
481 TYPE_MODULAR_P (div_type) = 1;
482 result = convert (op_type,
483 fold_build2 (TRUNC_MOD_EXPR, div_type,
484 convert (div_type, result), modulus));
487 /* For subtraction, add the modulus back if we are negative. */
488 else if (op_code == MINUS_EXPR)
490 result = gnat_protect_expr (result);
491 result = fold_build3 (COND_EXPR, op_type,
492 fold_build2 (LT_EXPR, boolean_type_node, result,
493 convert (op_type, integer_zero_node)),
494 fold_build2 (PLUS_EXPR, op_type, result, modulus),
498 /* For the other operations, subtract the modulus if we are >= it. */
501 result = gnat_protect_expr (result);
502 result = fold_build3 (COND_EXPR, op_type,
503 fold_build2 (GE_EXPR, boolean_type_node,
505 fold_build2 (MINUS_EXPR, op_type,
510 return convert (type, result);
513 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
514 desired for the result. Usually the operation is to be performed
515 in that type. For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
516 in which case the type to be used will be derived from the operands.
518 This function is very much unlike the ones for C and C++ since we
519 have already done any type conversion and matching required. All we
520 have to do here is validate the work done by SEM and handle subtypes. */
523 build_binary_op (enum tree_code op_code, tree result_type,
524 tree left_operand, tree right_operand)
526 tree left_type = TREE_TYPE (left_operand);
527 tree right_type = TREE_TYPE (right_operand);
528 tree left_base_type = get_base_type (left_type);
529 tree right_base_type = get_base_type (right_type);
530 tree operation_type = result_type;
531 tree best_type = NULL_TREE;
532 tree modulus, result;
533 bool has_side_effects = false;
536 && TREE_CODE (operation_type) == RECORD_TYPE
537 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
538 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
541 && !AGGREGATE_TYPE_P (operation_type)
542 && TYPE_EXTRA_SUBTYPE_P (operation_type))
543 operation_type = get_base_type (operation_type);
545 modulus = (operation_type
546 && TREE_CODE (operation_type) == INTEGER_TYPE
547 && TYPE_MODULAR_P (operation_type)
548 ? TYPE_MODULUS (operation_type) : NULL_TREE);
554 /* If there were integral or pointer conversions on the LHS, remove
555 them; we'll be putting them back below if needed. Likewise for
556 conversions between array and record types, except for justified
557 modular types. But don't do this if the right operand is not
558 BLKmode (for packed arrays) unless we are not changing the mode. */
559 while ((CONVERT_EXPR_P (left_operand)
560 || TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
561 && (((INTEGRAL_TYPE_P (left_type)
562 || POINTER_TYPE_P (left_type))
563 && (INTEGRAL_TYPE_P (TREE_TYPE
564 (TREE_OPERAND (left_operand, 0)))
565 || POINTER_TYPE_P (TREE_TYPE
566 (TREE_OPERAND (left_operand, 0)))))
567 || (((TREE_CODE (left_type) == RECORD_TYPE
568 && !TYPE_JUSTIFIED_MODULAR_P (left_type))
569 || TREE_CODE (left_type) == ARRAY_TYPE)
570 && ((TREE_CODE (TREE_TYPE
571 (TREE_OPERAND (left_operand, 0)))
573 || (TREE_CODE (TREE_TYPE
574 (TREE_OPERAND (left_operand, 0)))
576 && (TYPE_MODE (right_type) == BLKmode
577 || (TYPE_MODE (left_type)
578 == TYPE_MODE (TREE_TYPE
580 (left_operand, 0))))))))
582 left_operand = TREE_OPERAND (left_operand, 0);
583 left_type = TREE_TYPE (left_operand);
586 /* If a class-wide type may be involved, force use of the RHS type. */
587 if ((TREE_CODE (right_type) == RECORD_TYPE
588 || TREE_CODE (right_type) == UNION_TYPE)
589 && TYPE_ALIGN_OK (right_type))
590 operation_type = right_type;
592 /* If we are copying between padded objects with compatible types, use
593 the padded view of the objects, this is very likely more efficient.
594 Likewise for a padded object that is assigned a constructor, if we
595 can convert the constructor to the inner type, to avoid putting a
596 VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
597 actually copied anything. */
598 else if (TYPE_IS_PADDING_P (left_type)
599 && TREE_CONSTANT (TYPE_SIZE (left_type))
600 && ((TREE_CODE (right_operand) == COMPONENT_REF
602 (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
603 && gnat_types_compatible_p
605 TREE_TYPE (TREE_OPERAND (right_operand, 0))))
606 || (TREE_CODE (right_operand) == CONSTRUCTOR
607 && !CONTAINS_PLACEHOLDER_P
608 (DECL_SIZE (TYPE_FIELDS (left_type)))))
609 && !integer_zerop (TYPE_SIZE (right_type)))
610 operation_type = left_type;
612 /* Find the best type to use for copying between aggregate types. */
613 else if (((TREE_CODE (left_type) == ARRAY_TYPE
614 && TREE_CODE (right_type) == ARRAY_TYPE)
615 || (TREE_CODE (left_type) == RECORD_TYPE
616 && TREE_CODE (right_type) == RECORD_TYPE))
617 && (best_type = find_common_type (left_type, right_type)))
618 operation_type = best_type;
620 /* Otherwise use the LHS type. */
621 else if (!operation_type)
622 operation_type = left_type;
624 /* Ensure everything on the LHS is valid. If we have a field reference,
625 strip anything that get_inner_reference can handle. Then remove any
626 conversions between types having the same code and mode. And mark
627 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
628 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
629 result = left_operand;
632 tree restype = TREE_TYPE (result);
634 if (TREE_CODE (result) == COMPONENT_REF
635 || TREE_CODE (result) == ARRAY_REF
636 || TREE_CODE (result) == ARRAY_RANGE_REF)
637 while (handled_component_p (result))
638 result = TREE_OPERAND (result, 0);
639 else if (TREE_CODE (result) == REALPART_EXPR
640 || TREE_CODE (result) == IMAGPART_EXPR
641 || (CONVERT_EXPR_P (result)
642 && (((TREE_CODE (restype)
643 == TREE_CODE (TREE_TYPE
644 (TREE_OPERAND (result, 0))))
645 && (TYPE_MODE (TREE_TYPE
646 (TREE_OPERAND (result, 0)))
647 == TYPE_MODE (restype)))
648 || TYPE_ALIGN_OK (restype))))
649 result = TREE_OPERAND (result, 0);
650 else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
652 TREE_ADDRESSABLE (result) = 1;
653 result = TREE_OPERAND (result, 0);
659 gcc_assert (TREE_CODE (result) == INDIRECT_REF
660 || TREE_CODE (result) == NULL_EXPR
663 /* Convert the right operand to the operation type unless it is
664 either already of the correct type or if the type involves a
665 placeholder, since the RHS may not have the same record type. */
666 if (operation_type != right_type
667 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type)))
669 right_operand = convert (operation_type, right_operand);
670 right_type = operation_type;
673 /* If the left operand is not of the same type as the operation
674 type, wrap it up in a VIEW_CONVERT_EXPR. */
675 if (left_type != operation_type)
676 left_operand = unchecked_convert (operation_type, left_operand, false);
678 has_side_effects = true;
684 operation_type = TREE_TYPE (left_type);
686 /* ... fall through ... */
688 case ARRAY_RANGE_REF:
689 /* First look through conversion between type variants. Note that
690 this changes neither the operation type nor the type domain. */
691 if (TREE_CODE (left_operand) == VIEW_CONVERT_EXPR
692 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand, 0)))
693 == TYPE_MAIN_VARIANT (left_type))
695 left_operand = TREE_OPERAND (left_operand, 0);
696 left_type = TREE_TYPE (left_operand);
699 /* For a range, make sure the element type is consistent. */
700 if (op_code == ARRAY_RANGE_REF
701 && TREE_TYPE (operation_type) != TREE_TYPE (left_type))
702 operation_type = build_array_type (TREE_TYPE (left_type),
703 TYPE_DOMAIN (operation_type));
705 /* Then convert the right operand to its base type. This will prevent
706 unneeded sign conversions when sizetype is wider than integer. */
707 right_operand = convert (right_base_type, right_operand);
708 right_operand = convert (sizetype, right_operand);
710 if (!TREE_CONSTANT (right_operand)
711 || !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
712 gnat_mark_addressable (left_operand);
717 case TRUTH_ANDIF_EXPR:
718 case TRUTH_ORIF_EXPR:
722 #ifdef ENABLE_CHECKING
723 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
725 operation_type = left_base_type;
726 left_operand = convert (operation_type, left_operand);
727 right_operand = convert (operation_type, right_operand);
736 #ifdef ENABLE_CHECKING
737 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
739 /* If either operand is a NULL_EXPR, just return a new one. */
740 if (TREE_CODE (left_operand) == NULL_EXPR)
741 return build2 (op_code, result_type,
742 build1 (NULL_EXPR, integer_type_node,
743 TREE_OPERAND (left_operand, 0)),
746 else if (TREE_CODE (right_operand) == NULL_EXPR)
747 return build2 (op_code, result_type,
748 build1 (NULL_EXPR, integer_type_node,
749 TREE_OPERAND (right_operand, 0)),
752 /* If either object is a justified modular types, get the
753 fields from within. */
754 if (TREE_CODE (left_type) == RECORD_TYPE
755 && TYPE_JUSTIFIED_MODULAR_P (left_type))
757 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
759 left_type = TREE_TYPE (left_operand);
760 left_base_type = get_base_type (left_type);
763 if (TREE_CODE (right_type) == RECORD_TYPE
764 && TYPE_JUSTIFIED_MODULAR_P (right_type))
766 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
768 right_type = TREE_TYPE (right_operand);
769 right_base_type = get_base_type (right_type);
772 /* If both objects are arrays, compare them specially. */
773 if ((TREE_CODE (left_type) == ARRAY_TYPE
774 || (TREE_CODE (left_type) == INTEGER_TYPE
775 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
776 && (TREE_CODE (right_type) == ARRAY_TYPE
777 || (TREE_CODE (right_type) == INTEGER_TYPE
778 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
780 result = compare_arrays (input_location,
781 result_type, left_operand, right_operand);
782 if (op_code == NE_EXPR)
783 result = invert_truthvalue_loc (EXPR_LOCATION (result), result);
785 gcc_assert (op_code == EQ_EXPR);
790 /* Otherwise, the base types must be the same, unless they are both fat
791 pointer types or record types. In the latter case, use the best type
792 and convert both operands to that type. */
793 if (left_base_type != right_base_type)
795 if (TYPE_IS_FAT_POINTER_P (left_base_type)
796 && TYPE_IS_FAT_POINTER_P (right_base_type))
798 gcc_assert (TYPE_MAIN_VARIANT (left_base_type)
799 == TYPE_MAIN_VARIANT (right_base_type));
800 best_type = left_base_type;
803 else if (TREE_CODE (left_base_type) == RECORD_TYPE
804 && TREE_CODE (right_base_type) == RECORD_TYPE)
806 /* The only way this is permitted is if both types have the same
807 name. In that case, one of them must not be self-referential.
808 Use it as the best type. Even better with a fixed size. */
809 gcc_assert (TYPE_NAME (left_base_type)
810 && TYPE_NAME (left_base_type)
811 == TYPE_NAME (right_base_type));
813 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
814 best_type = left_base_type;
815 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
816 best_type = right_base_type;
817 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
818 best_type = left_base_type;
819 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
820 best_type = right_base_type;
828 left_operand = convert (best_type, left_operand);
829 right_operand = convert (best_type, right_operand);
833 left_operand = convert (left_base_type, left_operand);
834 right_operand = convert (right_base_type, right_operand);
837 /* If we are comparing a fat pointer against zero, we just need to
838 compare the data pointer. */
839 if (TYPE_IS_FAT_POINTER_P (left_base_type)
840 && TREE_CODE (right_operand) == CONSTRUCTOR
841 && integer_zerop (VEC_index (constructor_elt,
842 CONSTRUCTOR_ELTS (right_operand),
846 = build_component_ref (left_operand, NULL_TREE,
847 TYPE_FIELDS (left_base_type), false);
849 = convert (TREE_TYPE (left_operand), integer_zero_node);
859 /* The RHS of a shift can be any type. Also, ignore any modulus
860 (we used to abort, but this is needed for unchecked conversion
861 to modular types). Otherwise, processing is the same as normal. */
862 gcc_assert (operation_type == left_base_type);
864 left_operand = convert (operation_type, left_operand);
870 /* For binary modulus, if the inputs are in range, so are the
872 if (modulus && integer_pow2p (modulus))
877 gcc_assert (TREE_TYPE (result_type) == left_base_type
878 && TREE_TYPE (result_type) == right_base_type);
879 left_operand = convert (left_base_type, left_operand);
880 right_operand = convert (right_base_type, right_operand);
883 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
884 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
885 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
886 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
887 /* These always produce results lower than either operand. */
891 case POINTER_PLUS_EXPR:
892 gcc_assert (operation_type == left_base_type
893 && sizetype == right_base_type);
894 left_operand = convert (operation_type, left_operand);
895 right_operand = convert (sizetype, right_operand);
898 case PLUS_NOMOD_EXPR:
899 case MINUS_NOMOD_EXPR:
900 if (op_code == PLUS_NOMOD_EXPR)
903 op_code = MINUS_EXPR;
906 /* ... fall through ... */
910 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
911 other compilers. Contrary to C, Ada doesn't allow arithmetics in
912 these types but can generate addition/subtraction for Succ/Pred. */
914 && (TREE_CODE (operation_type) == ENUMERAL_TYPE
915 || TREE_CODE (operation_type) == BOOLEAN_TYPE))
916 operation_type = left_base_type = right_base_type
917 = gnat_type_for_mode (TYPE_MODE (operation_type),
918 TYPE_UNSIGNED (operation_type));
920 /* ... fall through ... */
924 /* The result type should be the same as the base types of the
925 both operands (and they should be the same). Convert
926 everything to the result type. */
928 gcc_assert (operation_type == left_base_type
929 && left_base_type == right_base_type);
930 left_operand = convert (operation_type, left_operand);
931 right_operand = convert (operation_type, right_operand);
934 if (modulus && !integer_pow2p (modulus))
936 result = nonbinary_modular_operation (op_code, operation_type,
937 left_operand, right_operand);
940 /* If either operand is a NULL_EXPR, just return a new one. */
941 else if (TREE_CODE (left_operand) == NULL_EXPR)
942 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
943 else if (TREE_CODE (right_operand) == NULL_EXPR)
944 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
945 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
946 result = fold (build4 (op_code, operation_type, left_operand,
947 right_operand, NULL_TREE, NULL_TREE));
950 = fold_build2 (op_code, operation_type, left_operand, right_operand);
952 if (TREE_CONSTANT (result))
954 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
956 TREE_THIS_NOTRAP (result) = 1;
957 if (TYPE_VOLATILE (operation_type))
958 TREE_THIS_VOLATILE (result) = 1;
961 TREE_CONSTANT (result)
962 |= (TREE_CONSTANT (left_operand) && TREE_CONSTANT (right_operand));
964 TREE_SIDE_EFFECTS (result) |= has_side_effects;
966 /* If we are working with modular types, perform the MOD operation
967 if something above hasn't eliminated the need for it. */
969 result = fold_build2 (FLOOR_MOD_EXPR, operation_type, result,
970 convert (operation_type, modulus));
972 if (result_type && result_type != operation_type)
973 result = convert (result_type, result);
978 /* Similar, but for unary operations. */
981 build_unary_op (enum tree_code op_code, tree result_type, tree operand)
983 tree type = TREE_TYPE (operand);
984 tree base_type = get_base_type (type);
985 tree operation_type = result_type;
987 bool side_effects = false;
990 && TREE_CODE (operation_type) == RECORD_TYPE
991 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
992 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
995 && !AGGREGATE_TYPE_P (operation_type)
996 && TYPE_EXTRA_SUBTYPE_P (operation_type))
997 operation_type = get_base_type (operation_type);
1003 if (!operation_type)
1004 result_type = operation_type = TREE_TYPE (type);
1006 gcc_assert (result_type == TREE_TYPE (type));
1008 result = fold_build1 (op_code, operation_type, operand);
1011 case TRUTH_NOT_EXPR:
1012 #ifdef ENABLE_CHECKING
1013 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
1015 result = invert_truthvalue_loc (EXPR_LOCATION (operand), operand);
1016 /* When not optimizing, fold the result as invert_truthvalue_loc
1017 doesn't fold the result of comparisons. This is intended to undo
1018 the trick used for boolean rvalues in gnat_to_gnu. */
1020 result = fold (result);
1023 case ATTR_ADDR_EXPR:
1025 switch (TREE_CODE (operand))
1028 case UNCONSTRAINED_ARRAY_REF:
1029 result = TREE_OPERAND (operand, 0);
1031 /* Make sure the type here is a pointer, not a reference.
1032 GCC wants pointer types for function addresses. */
1034 result_type = build_pointer_type (type);
1036 /* If the underlying object can alias everything, propagate the
1037 property since we are effectively retrieving the object. */
1038 if (POINTER_TYPE_P (TREE_TYPE (result))
1039 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1041 if (TREE_CODE (result_type) == POINTER_TYPE
1042 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1044 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1045 TYPE_MODE (result_type),
1047 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1048 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1050 = build_reference_type_for_mode (TREE_TYPE (result_type),
1051 TYPE_MODE (result_type),
1058 TREE_TYPE (result) = type = build_pointer_type (type);
1062 /* Fold a compound expression if it has unconstrained array type
1063 since the middle-end cannot handle it. But we don't it in the
1064 general case because it may introduce aliasing issues if the
1065 first operand is an indirect assignment and the second operand
1066 the corresponding address, e.g. for an allocator. */
1067 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
1069 result = build_unary_op (ADDR_EXPR, result_type,
1070 TREE_OPERAND (operand, 1));
1071 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1072 TREE_OPERAND (operand, 0), result);
1078 case ARRAY_RANGE_REF:
1081 /* If this is for 'Address, find the address of the prefix and add
1082 the offset to the field. Otherwise, do this the normal way. */
1083 if (op_code == ATTR_ADDR_EXPR)
1085 HOST_WIDE_INT bitsize;
1086 HOST_WIDE_INT bitpos;
1088 enum machine_mode mode;
1089 int unsignedp, volatilep;
1091 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1092 &mode, &unsignedp, &volatilep,
1095 /* If INNER is a padding type whose field has a self-referential
1096 size, convert to that inner type. We know the offset is zero
1097 and we need to have that type visible. */
1098 if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
1099 && CONTAINS_PLACEHOLDER_P
1100 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1101 (TREE_TYPE (inner))))))
1102 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1105 /* Compute the offset as a byte offset from INNER. */
1107 offset = size_zero_node;
1109 offset = size_binop (PLUS_EXPR, offset,
1110 size_int (bitpos / BITS_PER_UNIT));
1112 /* Take the address of INNER, convert the offset to void *, and
1113 add then. It will later be converted to the desired result
1115 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1116 inner = convert (ptr_void_type_node, inner);
1117 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1119 result = convert (build_pointer_type (TREE_TYPE (operand)),
1126 /* If this is just a constructor for a padded record, we can
1127 just take the address of the single field and convert it to
1128 a pointer to our type. */
1129 if (TYPE_IS_PADDING_P (type))
1131 result = VEC_index (constructor_elt,
1132 CONSTRUCTOR_ELTS (operand),
1134 result = convert (build_pointer_type (TREE_TYPE (operand)),
1135 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1142 if (AGGREGATE_TYPE_P (type)
1143 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1144 return build_unary_op (ADDR_EXPR, result_type,
1145 TREE_OPERAND (operand, 0));
1147 /* ... fallthru ... */
1149 case VIEW_CONVERT_EXPR:
1150 /* If this just a variant conversion or if the conversion doesn't
1151 change the mode, get the result type from this type and go down.
1152 This is needed for conversions of CONST_DECLs, to eventually get
1153 to the address of their CORRESPONDING_VARs. */
1154 if ((TYPE_MAIN_VARIANT (type)
1155 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1156 || (TYPE_MODE (type) != BLKmode
1157 && (TYPE_MODE (type)
1158 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1159 return build_unary_op (ADDR_EXPR,
1160 (result_type ? result_type
1161 : build_pointer_type (type)),
1162 TREE_OPERAND (operand, 0));
1166 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1168 /* ... fall through ... */
1173 /* If we are taking the address of a padded record whose field is
1174 contains a template, take the address of the template. */
1175 if (TYPE_IS_PADDING_P (type)
1176 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1177 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1179 type = TREE_TYPE (TYPE_FIELDS (type));
1180 operand = convert (type, operand);
1183 gnat_mark_addressable (operand);
1184 result = build_fold_addr_expr (operand);
1187 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1191 /* If we want to refer to an unconstrained array, use the appropriate
1192 expression to do so. This will never survive down to the back-end.
1193 But if TYPE is a thin pointer, first convert to a fat pointer. */
1194 if (TYPE_IS_THIN_POINTER_P (type)
1195 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1198 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1200 type = TREE_TYPE (operand);
1203 if (TYPE_IS_FAT_POINTER_P (type))
1205 result = build1 (UNCONSTRAINED_ARRAY_REF,
1206 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1207 TREE_READONLY (result)
1208 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1211 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1212 else if (TREE_CODE (operand) == ADDR_EXPR)
1213 result = TREE_OPERAND (operand, 0);
1215 /* Otherwise, build and fold the indirect reference. */
1218 result = build_fold_indirect_ref (operand);
1219 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1223 = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1229 tree modulus = ((operation_type
1230 && TREE_CODE (operation_type) == INTEGER_TYPE
1231 && TYPE_MODULAR_P (operation_type))
1232 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1233 int mod_pow2 = modulus && integer_pow2p (modulus);
1235 /* If this is a modular type, there are various possibilities
1236 depending on the operation and whether the modulus is a
1237 power of two or not. */
1241 gcc_assert (operation_type == base_type);
1242 operand = convert (operation_type, operand);
1244 /* The fastest in the negate case for binary modulus is
1245 the straightforward code; the TRUNC_MOD_EXPR below
1246 is an AND operation. */
1247 if (op_code == NEGATE_EXPR && mod_pow2)
1248 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1249 fold_build1 (NEGATE_EXPR, operation_type,
1253 /* For nonbinary negate case, return zero for zero operand,
1254 else return the modulus minus the operand. If the modulus
1255 is a power of two minus one, we can do the subtraction
1256 as an XOR since it is equivalent and faster on most machines. */
1257 else if (op_code == NEGATE_EXPR && !mod_pow2)
1259 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1261 convert (operation_type,
1262 integer_one_node))))
1263 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1266 result = fold_build2 (MINUS_EXPR, operation_type,
1269 result = fold_build3 (COND_EXPR, operation_type,
1270 fold_build2 (NE_EXPR,
1275 integer_zero_node)),
1280 /* For the NOT cases, we need a constant equal to
1281 the modulus minus one. For a binary modulus, we
1282 XOR against the constant and subtract the operand from
1283 that constant for nonbinary modulus. */
1285 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1286 convert (operation_type,
1290 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1293 result = fold_build2 (MINUS_EXPR, operation_type,
1301 /* ... fall through ... */
1304 gcc_assert (operation_type == base_type);
1305 result = fold_build1 (op_code, operation_type,
1306 convert (operation_type, operand));
1311 TREE_SIDE_EFFECTS (result) = 1;
1312 if (TREE_CODE (result) == INDIRECT_REF)
1313 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1316 if (result_type && TREE_TYPE (result) != result_type)
1317 result = convert (result_type, result);
1322 /* Similar, but for COND_EXPR. */
1325 build_cond_expr (tree result_type, tree condition_operand,
1326 tree true_operand, tree false_operand)
1328 bool addr_p = false;
1331 /* The front-end verified that result, true and false operands have
1332 same base type. Convert everything to the result type. */
1333 true_operand = convert (result_type, true_operand);
1334 false_operand = convert (result_type, false_operand);
1336 /* If the result type is unconstrained, take the address of the operands and
1337 then dereference the result. Likewise if the result type is passed by
1338 reference, but this is natively handled in the gimplifier. */
1339 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1340 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1342 result_type = build_pointer_type (result_type);
1343 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1344 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1348 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1349 true_operand, false_operand);
1351 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1352 in both arms, make sure it gets evaluated by moving it ahead of the
1353 conditional expression. This is necessary because it is evaluated
1354 in only one place at run time and would otherwise be uninitialized
1355 in one of the arms. */
1356 true_operand = skip_simple_arithmetic (true_operand);
1357 false_operand = skip_simple_arithmetic (false_operand);
1359 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1360 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1363 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1368 /* Similar, but for COMPOUND_EXPR. */
1371 build_compound_expr (tree result_type, tree stmt_operand, tree expr_operand)
1373 bool addr_p = false;
1376 /* If the result type is unconstrained, take the address of the operand and
1377 then dereference the result. Likewise if the result type is passed by
1378 reference, but this is natively handled in the gimplifier. */
1379 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1380 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1382 result_type = build_pointer_type (result_type);
1383 expr_operand = build_unary_op (ADDR_EXPR, result_type, expr_operand);
1387 result = fold_build2 (COMPOUND_EXPR, result_type, stmt_operand,
1391 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1395 /* Similar, but for RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR
1396 around the assignment of RET_VAL to RET_OBJ. Otherwise just build a bare
1397 RETURN_EXPR around RESULT_OBJ, which may be null in this case. */
1400 build_return_expr (tree ret_obj, tree ret_val)
1406 /* The gimplifier explicitly enforces the following invariant:
1415 As a consequence, type consistency dictates that we use the type
1416 of the RET_OBJ as the operation type. */
1417 tree operation_type = TREE_TYPE (ret_obj);
1419 /* Convert the right operand to the operation type. Note that it's the
1420 same transformation as in the MODIFY_EXPR case of build_binary_op,
1421 with the assumption that the type cannot involve a placeholder. */
1422 if (operation_type != TREE_TYPE (ret_val))
1423 ret_val = convert (operation_type, ret_val);
1425 result_expr = build2 (MODIFY_EXPR, operation_type, ret_obj, ret_val);
1428 result_expr = ret_obj;
1430 return build1 (RETURN_EXPR, void_type_node, result_expr);
1433 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1437 build_call_1_expr (tree fundecl, tree arg)
1439 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1440 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1442 TREE_SIDE_EFFECTS (call) = 1;
1446 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1450 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1452 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1453 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1455 TREE_SIDE_EFFECTS (call) = 1;
1459 /* Likewise to call FUNDECL with no arguments. */
1462 build_call_0_expr (tree fundecl)
1464 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1465 it possible to propagate DECL_IS_PURE on parameterless functions. */
1466 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1467 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1472 /* Call a function that raises an exception and pass the line number and file
1473 name, if requested. MSG says which exception function to call.
1475 GNAT_NODE is the gnat node conveying the source location for which the
1476 error should be signaled, or Empty in which case the error is signaled on
1477 the current ref_file_name/input_line.
1479 KIND says which kind of exception this is for
1480 (N_Raise_{Constraint,Storage,Program}_Error). */
1483 build_call_raise (int msg, Node_Id gnat_node, char kind)
1485 tree fndecl = gnat_raise_decls[msg];
1486 tree label = get_exception_label (kind);
1492 /* If this is to be done as a goto, handle that case. */
1495 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1496 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1498 /* If Local_Raise is present, generate
1499 Local_Raise (exception'Identity); */
1500 if (Present (local_raise))
1502 tree gnu_local_raise
1503 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1504 tree gnu_exception_entity
1505 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1507 = build_call_1_expr (gnu_local_raise,
1508 build_unary_op (ADDR_EXPR, NULL_TREE,
1509 gnu_exception_entity));
1511 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1512 gnu_call, gnu_result);}
1518 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1520 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1521 ? IDENTIFIER_POINTER
1522 (get_identifier (Get_Name_String
1524 (Get_Source_File_Index (Sloc (gnat_node))))))
1528 filename = build_string (len, str);
1530 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1531 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1533 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1534 build_index_type (size_int (len)));
1537 build_call_2_expr (fndecl,
1539 build_pointer_type (unsigned_char_type_node),
1541 build_int_cst (NULL_TREE, line_number));
1544 /* Similar to build_call_raise, for an index or range check exception as
1545 determined by MSG, with extra information generated of the form
1546 "INDEX out of range FIRST..LAST". */
1549 build_call_raise_range (int msg, Node_Id gnat_node,
1550 tree index, tree first, tree last)
1553 tree fndecl = gnat_raise_decls_ext[msg];
1555 int line_number, column_number;
1560 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1562 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1563 ? IDENTIFIER_POINTER
1564 (get_identifier (Get_Name_String
1566 (Get_Source_File_Index (Sloc (gnat_node))))))
1570 filename = build_string (len, str);
1571 if (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1573 line_number = Get_Logical_Line_Number (Sloc (gnat_node));
1574 column_number = Get_Column_Number (Sloc (gnat_node));
1578 line_number = input_line;
1582 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1583 build_index_type (size_int (len)));
1585 call = build_call_nary (TREE_TYPE (TREE_TYPE (fndecl)),
1586 build_unary_op (ADDR_EXPR, NULL_TREE, fndecl),
1589 build_pointer_type (unsigned_char_type_node),
1591 build_int_cst (NULL_TREE, line_number),
1592 build_int_cst (NULL_TREE, column_number),
1593 convert (integer_type_node, index),
1594 convert (integer_type_node, first),
1595 convert (integer_type_node, last));
1596 TREE_SIDE_EFFECTS (call) = 1;
1600 /* Similar to build_call_raise, with extra information about the column
1601 where the check failed. */
1604 build_call_raise_column (int msg, Node_Id gnat_node)
1606 tree fndecl = gnat_raise_decls_ext[msg];
1609 int line_number, column_number;
1614 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1616 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1617 ? IDENTIFIER_POINTER
1618 (get_identifier (Get_Name_String
1620 (Get_Source_File_Index (Sloc (gnat_node))))))
1624 filename = build_string (len, str);
1625 if (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1627 line_number = Get_Logical_Line_Number (Sloc (gnat_node));
1628 column_number = Get_Column_Number (Sloc (gnat_node));
1632 line_number = input_line;
1636 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1637 build_index_type (size_int (len)));
1639 call = build_call_nary (TREE_TYPE (TREE_TYPE (fndecl)),
1640 build_unary_op (ADDR_EXPR, NULL_TREE, fndecl),
1643 build_pointer_type (unsigned_char_type_node),
1645 build_int_cst (NULL_TREE, line_number),
1646 build_int_cst (NULL_TREE, column_number));
1647 TREE_SIDE_EFFECTS (call) = 1;
1651 /* qsort comparer for the bit positions of two constructor elements
1652 for record components. */
1655 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1657 const constructor_elt * const elmt1 = (const constructor_elt * const) rt1;
1658 const constructor_elt * const elmt2 = (const constructor_elt * const) rt2;
1659 const_tree const field1 = elmt1->index;
1660 const_tree const field2 = elmt2->index;
1662 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1664 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1667 /* Return a CONSTRUCTOR of TYPE whose elements are V. */
1670 gnat_build_constructor (tree type, VEC(constructor_elt,gc) *v)
1672 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1673 bool side_effects = false;
1674 tree result, obj, val;
1675 unsigned int n_elmts;
1677 /* Scan the elements to see if they are all constant or if any has side
1678 effects, to let us set global flags on the resulting constructor. Count
1679 the elements along the way for possible sorting purposes below. */
1680 FOR_EACH_CONSTRUCTOR_ELT (v, n_elmts, obj, val)
1682 /* The predicate must be in keeping with output_constructor. */
1683 if (!TREE_CONSTANT (val)
1684 || (TREE_CODE (type) == RECORD_TYPE
1685 && CONSTRUCTOR_BITFIELD_P (obj)
1686 && !initializer_constant_valid_for_bitfield_p (val))
1687 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1688 allconstant = false;
1690 if (TREE_SIDE_EFFECTS (val))
1691 side_effects = true;
1694 /* For record types with constant components only, sort field list
1695 by increasing bit position. This is necessary to ensure the
1696 constructor can be output as static data. */
1697 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1698 VEC_qsort (constructor_elt, v, compare_elmt_bitpos);
1700 result = build_constructor (type, v);
1701 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1702 TREE_SIDE_EFFECTS (result) = side_effects;
1703 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1707 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1708 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1709 for the field. Don't fold the result if NO_FOLD_P is true.
1711 We also handle the fact that we might have been passed a pointer to the
1712 actual record and know how to look for fields in variant parts. */
1715 build_simple_component_ref (tree record_variable, tree component,
1716 tree field, bool no_fold_p)
1718 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1719 tree ref, inner_variable;
1721 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1722 || TREE_CODE (record_type) == UNION_TYPE
1723 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1724 && TYPE_SIZE (record_type)
1725 && (component != 0) != (field != 0));
1727 /* If no field was specified, look for a field with the specified name
1728 in the current record only. */
1730 for (field = TYPE_FIELDS (record_type); field;
1731 field = TREE_CHAIN (field))
1732 if (DECL_NAME (field) == component)
1738 /* If this field is not in the specified record, see if we can find a field
1739 in the specified record whose original field is the same as this one. */
1740 if (DECL_CONTEXT (field) != record_type)
1744 /* First loop thru normal components. */
1745 for (new_field = TYPE_FIELDS (record_type); new_field;
1746 new_field = DECL_CHAIN (new_field))
1747 if (SAME_FIELD_P (field, new_field))
1750 /* Next, see if we're looking for an inherited component in an extension.
1751 If so, look thru the extension directly. */
1753 && TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1754 && TYPE_ALIGN_OK (record_type)
1755 && TREE_CODE (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1757 && TYPE_ALIGN_OK (TREE_TYPE (TREE_OPERAND (record_variable, 0))))
1759 ref = build_simple_component_ref (TREE_OPERAND (record_variable, 0),
1760 NULL_TREE, field, no_fold_p);
1765 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1766 the component in the first search. Doing this search in 2 steps
1767 is required to avoiding hidden homonymous fields in the
1770 for (new_field = TYPE_FIELDS (record_type); new_field;
1771 new_field = DECL_CHAIN (new_field))
1772 if (DECL_INTERNAL_P (new_field))
1775 = build_simple_component_ref (record_variable,
1776 NULL_TREE, new_field, no_fold_p);
1777 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1790 /* If the field's offset has overflowed, do not attempt to access it
1791 as doing so may trigger sanity checks deeper in the back-end.
1792 Note that we don't need to warn since this will be done on trying
1793 to declare the object. */
1794 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1795 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1798 /* Look through conversion between type variants. Note that this
1799 is transparent as far as the field is concerned. */
1800 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1801 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1803 inner_variable = TREE_OPERAND (record_variable, 0);
1805 inner_variable = record_variable;
1807 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1810 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1811 TREE_READONLY (ref) = 1;
1812 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1813 || TYPE_VOLATILE (record_type))
1814 TREE_THIS_VOLATILE (ref) = 1;
1819 /* The generic folder may punt in this case because the inner array type
1820 can be self-referential, but folding is in fact not problematic. */
1821 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1822 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1824 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1825 unsigned HOST_WIDE_INT idx;
1827 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1837 /* Like build_simple_component_ref, except that we give an error if the
1838 reference could not be found. */
1841 build_component_ref (tree record_variable, tree component,
1842 tree field, bool no_fold_p)
1844 tree ref = build_simple_component_ref (record_variable, component, field,
1850 /* If FIELD was specified, assume this is an invalid user field so raise
1851 Constraint_Error. Otherwise, we have no type to return so abort. */
1853 return build1 (NULL_EXPR, TREE_TYPE (field),
1854 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1855 N_Raise_Constraint_Error));
1858 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1859 identically. Process the case where a GNAT_PROC to call is provided. */
1862 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1863 Entity_Id gnat_proc, Entity_Id gnat_pool)
1865 tree gnu_proc = gnat_to_gnu (gnat_proc);
1866 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1869 /* The storage pools are obviously always tagged types, but the
1870 secondary stack uses the same mechanism and is not tagged. */
1871 if (Is_Tagged_Type (Etype (gnat_pool)))
1873 /* The size is the third parameter; the alignment is the
1875 Entity_Id gnat_size_type
1876 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1877 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1879 tree gnu_pool = gnat_to_gnu (gnat_pool);
1880 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1881 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1883 gnu_size = convert (gnu_size_type, gnu_size);
1884 gnu_align = convert (gnu_size_type, gnu_align);
1886 /* The first arg is always the address of the storage pool; next
1887 comes the address of the object, for a deallocator, then the
1888 size and alignment. */
1890 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1891 gnu_proc_addr, 4, gnu_pool_addr,
1892 gnu_obj, gnu_size, gnu_align);
1894 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1895 gnu_proc_addr, 3, gnu_pool_addr,
1896 gnu_size, gnu_align);
1899 /* Secondary stack case. */
1902 /* The size is the second parameter. */
1903 Entity_Id gnat_size_type
1904 = Etype (Next_Formal (First_Formal (gnat_proc)));
1905 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1907 gnu_size = convert (gnu_size_type, gnu_size);
1909 /* The first arg is the address of the object, for a deallocator,
1912 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1913 gnu_proc_addr, 2, gnu_obj, gnu_size);
1915 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1916 gnu_proc_addr, 1, gnu_size);
1919 TREE_SIDE_EFFECTS (gnu_call) = 1;
1923 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1924 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1925 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1929 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1931 /* When the DATA_TYPE alignment is stricter than what malloc offers
1932 (super-aligned case), we allocate an "aligning" wrapper type and return
1933 the address of its single data field with the malloc's return value
1934 stored just in front. */
1936 unsigned int data_align = TYPE_ALIGN (data_type);
1937 unsigned int default_allocator_alignment
1938 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1941 = ((data_align > default_allocator_alignment)
1942 ? make_aligning_type (data_type, data_align, data_size,
1943 default_allocator_alignment,
1944 POINTER_SIZE / BITS_PER_UNIT)
1948 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1952 /* On VMS, if pointers are 64-bit and the allocator size is 32-bit or
1953 Convention C, allocate 32-bit memory. */
1954 if (TARGET_ABI_OPEN_VMS
1955 && POINTER_SIZE == 64
1956 && Nkind (gnat_node) == N_Allocator
1957 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1958 || Convention (Etype (gnat_node)) == Convention_C))
1959 malloc_ptr = build_call_1_expr (malloc32_decl, size_to_malloc);
1961 malloc_ptr = build_call_1_expr (malloc_decl, size_to_malloc);
1965 /* Latch malloc's return value and get a pointer to the aligning field
1967 tree storage_ptr = gnat_protect_expr (malloc_ptr);
1969 tree aligning_record_addr
1970 = convert (build_pointer_type (aligning_type), storage_ptr);
1972 tree aligning_record
1973 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1976 = build_component_ref (aligning_record, NULL_TREE,
1977 TYPE_FIELDS (aligning_type), false);
1979 tree aligning_field_addr
1980 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1982 /* Then arrange to store the allocator's return value ahead
1984 tree storage_ptr_slot_addr
1985 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1986 convert (ptr_void_type_node, aligning_field_addr),
1987 size_int (-(HOST_WIDE_INT) POINTER_SIZE
1990 tree storage_ptr_slot
1991 = build_unary_op (INDIRECT_REF, NULL_TREE,
1992 convert (build_pointer_type (ptr_void_type_node),
1993 storage_ptr_slot_addr));
1996 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
1997 build_binary_op (MODIFY_EXPR, NULL_TREE,
1998 storage_ptr_slot, storage_ptr),
1999 aligning_field_addr);
2005 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
2006 designated by DATA_PTR using the __gnat_free entry point. */
2009 maybe_wrap_free (tree data_ptr, tree data_type)
2011 /* In the regular alignment case, we pass the data pointer straight to free.
2012 In the superaligned case, we need to retrieve the initial allocator
2013 return value, stored in front of the data block at allocation time. */
2015 unsigned int data_align = TYPE_ALIGN (data_type);
2016 unsigned int default_allocator_alignment
2017 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
2021 if (data_align > default_allocator_alignment)
2023 /* DATA_FRONT_PTR (void *)
2024 = (void *)DATA_PTR - (void *)sizeof (void *)) */
2027 (POINTER_PLUS_EXPR, ptr_void_type_node,
2028 convert (ptr_void_type_node, data_ptr),
2029 size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
2031 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
2034 (INDIRECT_REF, NULL_TREE,
2035 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
2038 free_ptr = data_ptr;
2040 return build_call_1_expr (free_decl, free_ptr);
2043 /* Build a GCC tree to call an allocation or deallocation function.
2044 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
2045 generate an allocator.
2047 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
2048 object type, used to determine the to-be-honored address alignment.
2049 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
2050 pool to use. If not present, malloc and free are used. GNAT_NODE is used
2051 to provide an error location for restriction violation messages. */
2054 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
2055 Entity_Id gnat_proc, Entity_Id gnat_pool,
2058 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
2060 /* Explicit proc to call ? This one is assumed to deal with the type
2061 alignment constraints. */
2062 if (Present (gnat_proc))
2063 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
2064 gnat_proc, gnat_pool);
2066 /* Otherwise, object to "free" or "malloc" with possible special processing
2067 for alignments stricter than what the default allocator honors. */
2069 return maybe_wrap_free (gnu_obj, gnu_type);
2072 /* Assert that we no longer can be called with this special pool. */
2073 gcc_assert (gnat_pool != -1);
2075 /* Check that we aren't violating the associated restriction. */
2076 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
2077 Check_No_Implicit_Heap_Alloc (gnat_node);
2079 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
2083 /* Build a GCC tree to correspond to allocating an object of TYPE whose
2084 initial value is INIT, if INIT is nonzero. Convert the expression to
2085 RESULT_TYPE, which must be some type of pointer. Return the tree.
2087 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
2088 the storage pool to use. GNAT_NODE is used to provide an error
2089 location for restriction violation messages. If IGNORE_INIT_TYPE is
2090 true, ignore the type of INIT for the purpose of determining the size;
2091 this will cause the maximum size to be allocated if TYPE is of
2092 self-referential size. */
2095 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
2096 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
2098 tree size = TYPE_SIZE_UNIT (type);
2101 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
2102 if (init && TREE_CODE (init) == NULL_EXPR)
2103 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
2105 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
2106 sizes of the object and its template. Allocate the whole thing and
2107 fill in the parts that are known. */
2108 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
2111 = build_unc_object_type_from_ptr (result_type, type,
2112 get_identifier ("ALLOC"), false);
2113 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
2114 tree storage_ptr_type = build_pointer_type (storage_type);
2117 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2120 /* If the size overflows, pass -1 so the allocator will raise
2122 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2123 size = ssize_int (-1);
2125 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2126 gnat_proc, gnat_pool, gnat_node);
2127 storage = convert (storage_ptr_type, gnat_protect_expr (storage));
2129 if (TYPE_IS_PADDING_P (type))
2131 type = TREE_TYPE (TYPE_FIELDS (type));
2133 init = convert (type, init);
2136 /* If there is an initializing expression, make a constructor for
2137 the entire object including the bounds and copy it into the
2138 object. If there is no initializing expression, just set the
2142 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, 2);
2144 CONSTRUCTOR_APPEND_ELT (v, TYPE_FIELDS (storage_type),
2145 build_template (template_type, type, init));
2146 CONSTRUCTOR_APPEND_ELT (v, DECL_CHAIN (TYPE_FIELDS (storage_type)),
2151 build2 (COMPOUND_EXPR, storage_ptr_type,
2153 (MODIFY_EXPR, storage_type,
2154 build_unary_op (INDIRECT_REF, NULL_TREE,
2155 convert (storage_ptr_type, storage)),
2156 gnat_build_constructor (storage_type, v)),
2157 convert (storage_ptr_type, storage)));
2161 (COMPOUND_EXPR, result_type,
2163 (MODIFY_EXPR, template_type,
2165 (build_unary_op (INDIRECT_REF, NULL_TREE,
2166 convert (storage_ptr_type, storage)),
2167 NULL_TREE, TYPE_FIELDS (storage_type), false),
2168 build_template (template_type, type, NULL_TREE)),
2169 convert (result_type, convert (storage_ptr_type, storage)));
2172 /* If we have an initializing expression, see if its size is simpler
2173 than the size from the type. */
2174 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2175 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2176 || CONTAINS_PLACEHOLDER_P (size)))
2177 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2179 /* If the size is still self-referential, reference the initializing
2180 expression, if it is present. If not, this must have been a
2181 call to allocate a library-level object, in which case we use
2182 the maximum size. */
2183 if (CONTAINS_PLACEHOLDER_P (size))
2185 if (!ignore_init_type && init)
2186 size = substitute_placeholder_in_expr (size, init);
2188 size = max_size (size, true);
2191 /* If the size overflows, pass -1 so the allocator will raise
2193 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2194 size = ssize_int (-1);
2196 result = convert (result_type,
2197 build_call_alloc_dealloc (NULL_TREE, size, type,
2198 gnat_proc, gnat_pool,
2201 /* If we have an initial value, protect the new address, assign the value
2202 and return the address with a COMPOUND_EXPR. */
2205 result = gnat_protect_expr (result);
2207 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2209 (MODIFY_EXPR, NULL_TREE,
2210 build_unary_op (INDIRECT_REF,
2211 TREE_TYPE (TREE_TYPE (result)), result),
2216 return convert (result_type, result);
2219 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2220 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2221 how we derive the source location to raise C_E on an out of range
2225 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2227 tree parm_decl = get_gnu_tree (gnat_formal);
2228 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2230 const bool do_range_check
2232 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2233 VEC(constructor_elt,gc) *v = NULL;
2235 expr = maybe_unconstrained_array (expr);
2236 gnat_mark_addressable (expr);
2238 for (field = TYPE_FIELDS (record_type); field; field = DECL_CHAIN (field))
2240 tree conexpr = convert (TREE_TYPE (field),
2241 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2242 (DECL_INITIAL (field), expr));
2244 /* Check to ensure that only 32-bit pointers are passed in
2245 32-bit descriptors */
2247 && strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2250 = build_pointer_type_for_mode (void_type_node, DImode, false);
2251 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2253 = build_int_cstu (long_integer_type_node, 0x80000000);
2255 add_stmt (build3 (COND_EXPR, void_type_node,
2256 build_binary_op (GE_EXPR, boolean_type_node,
2257 convert (long_integer_type_node,
2260 build_call_raise (CE_Range_Check_Failed,
2262 N_Raise_Constraint_Error),
2265 CONSTRUCTOR_APPEND_ELT (v, field, conexpr);
2268 return gnat_build_constructor (record_type, v);
2271 /* Indicate that we need to take the address of T and that it therefore
2272 should not be allocated in a register. Returns true if successful. */
2275 gnat_mark_addressable (tree t)
2278 switch (TREE_CODE (t))
2283 case ARRAY_RANGE_REF:
2286 case VIEW_CONVERT_EXPR:
2287 case NON_LVALUE_EXPR:
2289 t = TREE_OPERAND (t, 0);
2293 t = TREE_OPERAND (t, 1);
2297 TREE_ADDRESSABLE (t) = 1;
2303 TREE_ADDRESSABLE (t) = 1;
2307 TREE_ADDRESSABLE (t) = 1;
2311 return DECL_CONST_CORRESPONDING_VAR (t)
2312 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
2319 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2320 but we know how to handle our own nodes. */
2323 gnat_save_expr (tree exp)
2325 tree type = TREE_TYPE (exp);
2326 enum tree_code code = TREE_CODE (exp);
2328 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2331 if (code == UNCONSTRAINED_ARRAY_REF)
2333 tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
2334 TREE_READONLY (t) = TYPE_READONLY (type);
2338 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2339 This may be more efficient, but will also allow us to more easily find
2340 the match for the PLACEHOLDER_EXPR. */
2341 if (code == COMPONENT_REF
2342 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2343 return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
2344 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2346 return save_expr (exp);
2349 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2350 is optimized under the assumption that EXP's value doesn't change before
2351 its subsequent reuse(s) except through its potential reevaluation. */
2354 gnat_protect_expr (tree exp)
2356 tree type = TREE_TYPE (exp);
2357 enum tree_code code = TREE_CODE (exp);
2359 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2362 /* If EXP has no side effects, we theoritically don't need to do anything.
2363 However, we may be recursively passed more and more complex expressions
2364 involving checks which will be reused multiple times and eventually be
2365 unshared for gimplification; in order to avoid a complexity explosion
2366 at that point, we protect any expressions more complex than a simple
2367 arithmetic expression. */
2368 if (!TREE_SIDE_EFFECTS (exp))
2370 tree inner = skip_simple_arithmetic (exp);
2371 if (!EXPR_P (inner) || REFERENCE_CLASS_P (inner))
2375 /* If this is a conversion, protect what's inside the conversion. */
2376 if (code == NON_LVALUE_EXPR
2377 || CONVERT_EXPR_CODE_P (code)
2378 || code == VIEW_CONVERT_EXPR)
2379 return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2381 /* If we're indirectly referencing something, we only need to protect the
2382 address since the data itself can't change in these situations. */
2383 if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
2385 tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2386 TREE_READONLY (t) = TYPE_READONLY (type);
2390 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2391 This may be more efficient, but will also allow us to more easily find
2392 the match for the PLACEHOLDER_EXPR. */
2393 if (code == COMPONENT_REF
2394 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2395 return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
2396 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2398 /* If this is a fat pointer or something that can be placed in a register,
2399 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2400 returned via invisible reference in most ABIs so the temporary will
2401 directly be filled by the callee. */
2402 if (TYPE_IS_FAT_POINTER_P (type)
2403 || TYPE_MODE (type) != BLKmode
2404 || code == CALL_EXPR)
2405 return save_expr (exp);
2407 /* Otherwise reference, protect the address and dereference. */
2409 build_unary_op (INDIRECT_REF, type,
2410 save_expr (build_unary_op (ADDR_EXPR,
2411 build_reference_type (type),
2415 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2416 argument to force evaluation of everything. */
2419 gnat_stabilize_reference_1 (tree e, bool force)
2421 enum tree_code code = TREE_CODE (e);
2422 tree type = TREE_TYPE (e);
2425 /* We cannot ignore const expressions because it might be a reference
2426 to a const array but whose index contains side-effects. But we can
2427 ignore things that are actual constant or that already have been
2428 handled by this function. */
2429 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2432 switch (TREE_CODE_CLASS (code))
2434 case tcc_exceptional:
2435 case tcc_declaration:
2436 case tcc_comparison:
2437 case tcc_expression:
2440 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2441 fat pointer. This may be more efficient, but will also allow
2442 us to more easily find the match for the PLACEHOLDER_EXPR. */
2443 if (code == COMPONENT_REF
2444 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
2446 = build3 (code, type,
2447 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2448 TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
2449 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2450 so that it will only be evaluated once. */
2451 /* The tcc_reference and tcc_comparison classes could be handled as
2452 below, but it is generally faster to only evaluate them once. */
2453 else if (TREE_SIDE_EFFECTS (e) || force)
2454 return save_expr (e);
2460 /* Recursively stabilize each operand. */
2462 = build2 (code, type,
2463 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2464 gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
2468 /* Recursively stabilize each operand. */
2470 = build1 (code, type,
2471 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
2478 /* See similar handling in gnat_stabilize_reference. */
2479 TREE_READONLY (result) = TREE_READONLY (e);
2480 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
2481 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2483 if (code == INDIRECT_REF || code == ARRAY_REF || code == ARRAY_RANGE_REF)
2484 TREE_THIS_NOTRAP (result) = TREE_THIS_NOTRAP (e);
2489 /* This is equivalent to stabilize_reference in tree.c but we know how to
2490 handle our own nodes and we take extra arguments. FORCE says whether to
2491 force evaluation of everything. We set SUCCESS to true unless we walk
2492 through something we don't know how to stabilize. */
2495 gnat_stabilize_reference (tree ref, bool force, bool *success)
2497 tree type = TREE_TYPE (ref);
2498 enum tree_code code = TREE_CODE (ref);
2501 /* Assume we'll success unless proven otherwise. */
2511 /* No action is needed in this case. */
2517 case FIX_TRUNC_EXPR:
2518 case VIEW_CONVERT_EXPR:
2520 = build1 (code, type,
2521 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2526 case UNCONSTRAINED_ARRAY_REF:
2527 result = build1 (code, type,
2528 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
2533 result = build3 (COMPONENT_REF, type,
2534 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2536 TREE_OPERAND (ref, 1), NULL_TREE);
2540 result = build3 (BIT_FIELD_REF, type,
2541 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2543 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2545 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
2550 case ARRAY_RANGE_REF:
2551 result = build4 (code, type,
2552 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2554 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2556 NULL_TREE, NULL_TREE);
2560 result = gnat_stabilize_reference_1 (ref, force);
2564 result = build2 (COMPOUND_EXPR, type,
2565 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2567 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2572 /* Constructors with 1 element are used extensively to formally
2573 convert objects to special wrapping types. */
2574 if (TREE_CODE (type) == RECORD_TYPE
2575 && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
2578 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
2580 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
2582 = build_constructor_single (type, index,
2583 gnat_stabilize_reference_1 (value,
2595 ref = error_mark_node;
2597 /* ... fall through to failure ... */
2599 /* If arg isn't a kind of lvalue we recognize, make no change.
2600 Caller should recognize the error for an invalid lvalue. */
2607 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2608 may not be sustained across some paths, such as the way via build1 for
2609 INDIRECT_REF. We reset those flags here in the general case, which is
2610 consistent with the GCC version of this routine.
2612 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2613 paths introduce side-effects where there was none initially (e.g. if a
2614 SAVE_EXPR is built) and we also want to keep track of that. */
2615 TREE_READONLY (result) = TREE_READONLY (ref);
2616 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
2617 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);