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 (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 = build_binary_op (LT_EXPR, result_type, ub1, lb1);
300 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
301 if (EXPR_P (comparison))
302 SET_EXPR_LOCATION (comparison, input_location);
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 = build_binary_op (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, input_location);
331 this_a1_is_null = build_binary_op (LT_EXPR, result_type, ub1, lb1);
332 if (EXPR_P (this_a1_is_null))
333 SET_EXPR_LOCATION (this_a1_is_null, input_location);
335 this_a2_is_null = convert (result_type, boolean_false_node);
338 /* Otherwise, compare the computed lengths. */
341 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
342 length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
345 = build_binary_op (EQ_EXPR, result_type, length1, length2);
346 if (EXPR_P (comparison))
347 SET_EXPR_LOCATION (comparison, input_location);
349 /* If the length expression is of the form (cond ? val : 0), assume
350 that cond is equivalent to (length != 0). That's guaranteed by
351 construction of the array types in gnat_to_gnu_entity. */
352 if (TREE_CODE (length1) == COND_EXPR
353 && integer_zerop (TREE_OPERAND (length1, 2)))
354 this_a1_is_null = invert_truthvalue (TREE_OPERAND (length1, 0));
356 this_a1_is_null = build_binary_op (EQ_EXPR, result_type, length1,
358 if (EXPR_P (this_a1_is_null))
359 SET_EXPR_LOCATION (this_a1_is_null, input_location);
361 /* Likewise for the second array. */
362 if (TREE_CODE (length2) == COND_EXPR
363 && integer_zerop (TREE_OPERAND (length2, 2)))
364 this_a2_is_null = invert_truthvalue (TREE_OPERAND (length2, 0));
366 this_a2_is_null = build_binary_op (EQ_EXPR, result_type, length2,
368 if (EXPR_P (this_a2_is_null))
369 SET_EXPR_LOCATION (this_a2_is_null, input_location);
372 /* Append expressions for this dimension to the final expressions. */
373 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
376 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
377 this_a1_is_null, a1_is_null);
379 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
380 this_a2_is_null, a2_is_null);
386 /* Unless the length of some dimension is known to be zero, compare the
387 data in the array. */
390 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
395 a1 = convert (type, a1),
396 a2 = convert (type, a2);
399 comparison = fold_build2 (EQ_EXPR, result_type, a1, a2);
400 if (EXPR_P (comparison))
401 SET_EXPR_LOCATION (comparison, input_location);
404 = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result, comparison);
407 /* The result is also true if both sizes are zero. */
408 result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
409 build_binary_op (TRUTH_ANDIF_EXPR, result_type,
410 a1_is_null, a2_is_null),
413 /* If either operand has side-effects, they have to be evaluated before
414 starting the comparison above since the place they would be otherwise
415 evaluated could be wrong. */
416 if (a1_side_effects_p)
417 result = build2 (COMPOUND_EXPR, result_type, a1, result);
419 if (a2_side_effects_p)
420 result = build2 (COMPOUND_EXPR, result_type, a2, result);
425 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
426 type TYPE. We know that TYPE is a modular type with a nonbinary
430 nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
433 tree modulus = TYPE_MODULUS (type);
434 unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
435 unsigned int precision;
436 bool unsignedp = true;
440 /* If this is an addition of a constant, convert it to a subtraction
441 of a constant since we can do that faster. */
442 if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
444 rhs = fold_build2 (MINUS_EXPR, type, modulus, rhs);
445 op_code = MINUS_EXPR;
448 /* For the logical operations, we only need PRECISION bits. For
449 addition and subtraction, we need one more and for multiplication we
450 need twice as many. But we never want to make a size smaller than
452 if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
453 needed_precision += 1;
454 else if (op_code == MULT_EXPR)
455 needed_precision *= 2;
457 precision = MAX (needed_precision, TYPE_PRECISION (op_type));
459 /* Unsigned will do for everything but subtraction. */
460 if (op_code == MINUS_EXPR)
463 /* If our type is the wrong signedness or isn't wide enough, make a new
464 type and convert both our operands to it. */
465 if (TYPE_PRECISION (op_type) < precision
466 || TYPE_UNSIGNED (op_type) != unsignedp)
468 /* Copy the node so we ensure it can be modified to make it modular. */
469 op_type = copy_node (gnat_type_for_size (precision, unsignedp));
470 modulus = convert (op_type, modulus);
471 SET_TYPE_MODULUS (op_type, modulus);
472 TYPE_MODULAR_P (op_type) = 1;
473 lhs = convert (op_type, lhs);
474 rhs = convert (op_type, rhs);
477 /* Do the operation, then we'll fix it up. */
478 result = fold_build2 (op_code, op_type, lhs, rhs);
480 /* For multiplication, we have no choice but to do a full modulus
481 operation. However, we want to do this in the narrowest
483 if (op_code == MULT_EXPR)
485 tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
486 modulus = convert (div_type, modulus);
487 SET_TYPE_MODULUS (div_type, modulus);
488 TYPE_MODULAR_P (div_type) = 1;
489 result = convert (op_type,
490 fold_build2 (TRUNC_MOD_EXPR, div_type,
491 convert (div_type, result), modulus));
494 /* For subtraction, add the modulus back if we are negative. */
495 else if (op_code == MINUS_EXPR)
497 result = gnat_protect_expr (result);
498 result = fold_build3 (COND_EXPR, op_type,
499 fold_build2 (LT_EXPR, boolean_type_node, result,
500 convert (op_type, integer_zero_node)),
501 fold_build2 (PLUS_EXPR, op_type, result, modulus),
505 /* For the other operations, subtract the modulus if we are >= it. */
508 result = gnat_protect_expr (result);
509 result = fold_build3 (COND_EXPR, op_type,
510 fold_build2 (GE_EXPR, boolean_type_node,
512 fold_build2 (MINUS_EXPR, op_type,
517 return convert (type, result);
520 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
521 desired for the result. Usually the operation is to be performed
522 in that type. For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
523 in which case the type to be used will be derived from the operands.
525 This function is very much unlike the ones for C and C++ since we
526 have already done any type conversion and matching required. All we
527 have to do here is validate the work done by SEM and handle subtypes. */
530 build_binary_op (enum tree_code op_code, tree result_type,
531 tree left_operand, tree right_operand)
533 tree left_type = TREE_TYPE (left_operand);
534 tree right_type = TREE_TYPE (right_operand);
535 tree left_base_type = get_base_type (left_type);
536 tree right_base_type = get_base_type (right_type);
537 tree operation_type = result_type;
538 tree best_type = NULL_TREE;
539 tree modulus, result;
540 bool has_side_effects = false;
543 && TREE_CODE (operation_type) == RECORD_TYPE
544 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
545 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
548 && !AGGREGATE_TYPE_P (operation_type)
549 && TYPE_EXTRA_SUBTYPE_P (operation_type))
550 operation_type = get_base_type (operation_type);
552 modulus = (operation_type
553 && TREE_CODE (operation_type) == INTEGER_TYPE
554 && TYPE_MODULAR_P (operation_type)
555 ? TYPE_MODULUS (operation_type) : NULL_TREE);
561 /* If there were integral or pointer conversions on the LHS, remove
562 them; we'll be putting them back below if needed. Likewise for
563 conversions between array and record types, except for justified
564 modular types. But don't do this if the right operand is not
565 BLKmode (for packed arrays) unless we are not changing the mode. */
566 while ((CONVERT_EXPR_P (left_operand)
567 || TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
568 && (((INTEGRAL_TYPE_P (left_type)
569 || POINTER_TYPE_P (left_type))
570 && (INTEGRAL_TYPE_P (TREE_TYPE
571 (TREE_OPERAND (left_operand, 0)))
572 || POINTER_TYPE_P (TREE_TYPE
573 (TREE_OPERAND (left_operand, 0)))))
574 || (((TREE_CODE (left_type) == RECORD_TYPE
575 && !TYPE_JUSTIFIED_MODULAR_P (left_type))
576 || TREE_CODE (left_type) == ARRAY_TYPE)
577 && ((TREE_CODE (TREE_TYPE
578 (TREE_OPERAND (left_operand, 0)))
580 || (TREE_CODE (TREE_TYPE
581 (TREE_OPERAND (left_operand, 0)))
583 && (TYPE_MODE (right_type) == BLKmode
584 || (TYPE_MODE (left_type)
585 == TYPE_MODE (TREE_TYPE
587 (left_operand, 0))))))))
589 left_operand = TREE_OPERAND (left_operand, 0);
590 left_type = TREE_TYPE (left_operand);
593 /* If a class-wide type may be involved, force use of the RHS type. */
594 if ((TREE_CODE (right_type) == RECORD_TYPE
595 || TREE_CODE (right_type) == UNION_TYPE)
596 && TYPE_ALIGN_OK (right_type))
597 operation_type = right_type;
599 /* If we are copying between padded objects with compatible types, use
600 the padded view of the objects, this is very likely more efficient.
601 Likewise for a padded object that is assigned a constructor, if we
602 can convert the constructor to the inner type, to avoid putting a
603 VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
604 actually copied anything. */
605 else if (TYPE_IS_PADDING_P (left_type)
606 && TREE_CONSTANT (TYPE_SIZE (left_type))
607 && ((TREE_CODE (right_operand) == COMPONENT_REF
609 (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
610 && gnat_types_compatible_p
612 TREE_TYPE (TREE_OPERAND (right_operand, 0))))
613 || (TREE_CODE (right_operand) == CONSTRUCTOR
614 && !CONTAINS_PLACEHOLDER_P
615 (DECL_SIZE (TYPE_FIELDS (left_type)))))
616 && !integer_zerop (TYPE_SIZE (right_type)))
617 operation_type = left_type;
619 /* Find the best type to use for copying between aggregate types. */
620 else if (((TREE_CODE (left_type) == ARRAY_TYPE
621 && TREE_CODE (right_type) == ARRAY_TYPE)
622 || (TREE_CODE (left_type) == RECORD_TYPE
623 && TREE_CODE (right_type) == RECORD_TYPE))
624 && (best_type = find_common_type (left_type, right_type)))
625 operation_type = best_type;
627 /* Otherwise use the LHS type. */
628 else if (!operation_type)
629 operation_type = left_type;
631 /* Ensure everything on the LHS is valid. If we have a field reference,
632 strip anything that get_inner_reference can handle. Then remove any
633 conversions between types having the same code and mode. And mark
634 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
635 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
636 result = left_operand;
639 tree restype = TREE_TYPE (result);
641 if (TREE_CODE (result) == COMPONENT_REF
642 || TREE_CODE (result) == ARRAY_REF
643 || TREE_CODE (result) == ARRAY_RANGE_REF)
644 while (handled_component_p (result))
645 result = TREE_OPERAND (result, 0);
646 else if (TREE_CODE (result) == REALPART_EXPR
647 || TREE_CODE (result) == IMAGPART_EXPR
648 || (CONVERT_EXPR_P (result)
649 && (((TREE_CODE (restype)
650 == TREE_CODE (TREE_TYPE
651 (TREE_OPERAND (result, 0))))
652 && (TYPE_MODE (TREE_TYPE
653 (TREE_OPERAND (result, 0)))
654 == TYPE_MODE (restype)))
655 || TYPE_ALIGN_OK (restype))))
656 result = TREE_OPERAND (result, 0);
657 else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
659 TREE_ADDRESSABLE (result) = 1;
660 result = TREE_OPERAND (result, 0);
666 gcc_assert (TREE_CODE (result) == INDIRECT_REF
667 || TREE_CODE (result) == NULL_EXPR
670 /* Convert the right operand to the operation type unless it is
671 either already of the correct type or if the type involves a
672 placeholder, since the RHS may not have the same record type. */
673 if (operation_type != right_type
674 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type)))
676 right_operand = convert (operation_type, right_operand);
677 right_type = operation_type;
680 /* If the left operand is not of the same type as the operation
681 type, wrap it up in a VIEW_CONVERT_EXPR. */
682 if (left_type != operation_type)
683 left_operand = unchecked_convert (operation_type, left_operand, false);
685 has_side_effects = true;
691 operation_type = TREE_TYPE (left_type);
693 /* ... fall through ... */
695 case ARRAY_RANGE_REF:
696 /* First look through conversion between type variants. Note that
697 this changes neither the operation type nor the type domain. */
698 if (TREE_CODE (left_operand) == VIEW_CONVERT_EXPR
699 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand, 0)))
700 == TYPE_MAIN_VARIANT (left_type))
702 left_operand = TREE_OPERAND (left_operand, 0);
703 left_type = TREE_TYPE (left_operand);
706 /* For a range, make sure the element type is consistent. */
707 if (op_code == ARRAY_RANGE_REF
708 && TREE_TYPE (operation_type) != TREE_TYPE (left_type))
709 operation_type = build_array_type (TREE_TYPE (left_type),
710 TYPE_DOMAIN (operation_type));
712 /* Then convert the right operand to its base type. This will prevent
713 unneeded sign conversions when sizetype is wider than integer. */
714 right_operand = convert (right_base_type, right_operand);
715 right_operand = convert (sizetype, right_operand);
717 if (!TREE_CONSTANT (right_operand)
718 || !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
719 gnat_mark_addressable (left_operand);
724 case TRUTH_ANDIF_EXPR:
725 case TRUTH_ORIF_EXPR:
729 #ifdef ENABLE_CHECKING
730 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
732 operation_type = left_base_type;
733 left_operand = convert (operation_type, left_operand);
734 right_operand = convert (operation_type, right_operand);
743 #ifdef ENABLE_CHECKING
744 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
746 /* If either operand is a NULL_EXPR, just return a new one. */
747 if (TREE_CODE (left_operand) == NULL_EXPR)
748 return build2 (op_code, result_type,
749 build1 (NULL_EXPR, integer_type_node,
750 TREE_OPERAND (left_operand, 0)),
753 else if (TREE_CODE (right_operand) == NULL_EXPR)
754 return build2 (op_code, result_type,
755 build1 (NULL_EXPR, integer_type_node,
756 TREE_OPERAND (right_operand, 0)),
759 /* If either object is a justified modular types, get the
760 fields from within. */
761 if (TREE_CODE (left_type) == RECORD_TYPE
762 && TYPE_JUSTIFIED_MODULAR_P (left_type))
764 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
766 left_type = TREE_TYPE (left_operand);
767 left_base_type = get_base_type (left_type);
770 if (TREE_CODE (right_type) == RECORD_TYPE
771 && TYPE_JUSTIFIED_MODULAR_P (right_type))
773 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
775 right_type = TREE_TYPE (right_operand);
776 right_base_type = get_base_type (right_type);
779 /* If both objects are arrays, compare them specially. */
780 if ((TREE_CODE (left_type) == ARRAY_TYPE
781 || (TREE_CODE (left_type) == INTEGER_TYPE
782 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
783 && (TREE_CODE (right_type) == ARRAY_TYPE
784 || (TREE_CODE (right_type) == INTEGER_TYPE
785 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
787 result = compare_arrays (result_type, left_operand, right_operand);
789 if (op_code == NE_EXPR)
790 result = invert_truthvalue_loc (EXPR_LOCATION (result), result);
792 gcc_assert (op_code == EQ_EXPR);
797 /* Otherwise, the base types must be the same, unless they are both fat
798 pointer types or record types. In the latter case, use the best type
799 and convert both operands to that type. */
800 if (left_base_type != right_base_type)
802 if (TYPE_IS_FAT_POINTER_P (left_base_type)
803 && TYPE_IS_FAT_POINTER_P (right_base_type))
805 gcc_assert (TYPE_MAIN_VARIANT (left_base_type)
806 == TYPE_MAIN_VARIANT (right_base_type));
807 best_type = left_base_type;
810 else if (TREE_CODE (left_base_type) == RECORD_TYPE
811 && TREE_CODE (right_base_type) == RECORD_TYPE)
813 /* The only way this is permitted is if both types have the same
814 name. In that case, one of them must not be self-referential.
815 Use it as the best type. Even better with a fixed size. */
816 gcc_assert (TYPE_NAME (left_base_type)
817 && TYPE_NAME (left_base_type)
818 == TYPE_NAME (right_base_type));
820 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
821 best_type = left_base_type;
822 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
823 best_type = right_base_type;
824 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
825 best_type = left_base_type;
826 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
827 best_type = right_base_type;
835 left_operand = convert (best_type, left_operand);
836 right_operand = convert (best_type, right_operand);
840 left_operand = convert (left_base_type, left_operand);
841 right_operand = convert (right_base_type, right_operand);
844 /* If we are comparing a fat pointer against zero, we just need to
845 compare the data pointer. */
846 if (TYPE_IS_FAT_POINTER_P (left_base_type)
847 && TREE_CODE (right_operand) == CONSTRUCTOR
848 && integer_zerop (VEC_index (constructor_elt,
849 CONSTRUCTOR_ELTS (right_operand),
853 = build_component_ref (left_operand, NULL_TREE,
854 TYPE_FIELDS (left_base_type), false);
856 = convert (TREE_TYPE (left_operand), integer_zero_node);
866 /* The RHS of a shift can be any type. Also, ignore any modulus
867 (we used to abort, but this is needed for unchecked conversion
868 to modular types). Otherwise, processing is the same as normal. */
869 gcc_assert (operation_type == left_base_type);
871 left_operand = convert (operation_type, left_operand);
877 /* For binary modulus, if the inputs are in range, so are the
879 if (modulus && integer_pow2p (modulus))
884 gcc_assert (TREE_TYPE (result_type) == left_base_type
885 && TREE_TYPE (result_type) == right_base_type);
886 left_operand = convert (left_base_type, left_operand);
887 right_operand = convert (right_base_type, right_operand);
890 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
891 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
892 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
893 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
894 /* These always produce results lower than either operand. */
898 case POINTER_PLUS_EXPR:
899 gcc_assert (operation_type == left_base_type
900 && sizetype == right_base_type);
901 left_operand = convert (operation_type, left_operand);
902 right_operand = convert (sizetype, right_operand);
905 case PLUS_NOMOD_EXPR:
906 case MINUS_NOMOD_EXPR:
907 if (op_code == PLUS_NOMOD_EXPR)
910 op_code = MINUS_EXPR;
913 /* ... fall through ... */
917 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
918 other compilers. Contrary to C, Ada doesn't allow arithmetics in
919 these types but can generate addition/subtraction for Succ/Pred. */
921 && (TREE_CODE (operation_type) == ENUMERAL_TYPE
922 || TREE_CODE (operation_type) == BOOLEAN_TYPE))
923 operation_type = left_base_type = right_base_type
924 = gnat_type_for_mode (TYPE_MODE (operation_type),
925 TYPE_UNSIGNED (operation_type));
927 /* ... fall through ... */
931 /* The result type should be the same as the base types of the
932 both operands (and they should be the same). Convert
933 everything to the result type. */
935 gcc_assert (operation_type == left_base_type
936 && left_base_type == right_base_type);
937 left_operand = convert (operation_type, left_operand);
938 right_operand = convert (operation_type, right_operand);
941 if (modulus && !integer_pow2p (modulus))
943 result = nonbinary_modular_operation (op_code, operation_type,
944 left_operand, right_operand);
947 /* If either operand is a NULL_EXPR, just return a new one. */
948 else if (TREE_CODE (left_operand) == NULL_EXPR)
949 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
950 else if (TREE_CODE (right_operand) == NULL_EXPR)
951 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
952 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
953 result = fold (build4 (op_code, operation_type, left_operand,
954 right_operand, NULL_TREE, NULL_TREE));
957 = fold_build2 (op_code, operation_type, left_operand, right_operand);
959 if (TREE_CONSTANT (result))
961 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
963 TREE_THIS_NOTRAP (result) = 1;
964 if (TYPE_VOLATILE (operation_type))
965 TREE_THIS_VOLATILE (result) = 1;
968 TREE_CONSTANT (result)
969 |= (TREE_CONSTANT (left_operand) && TREE_CONSTANT (right_operand));
971 TREE_SIDE_EFFECTS (result) |= has_side_effects;
973 /* If we are working with modular types, perform the MOD operation
974 if something above hasn't eliminated the need for it. */
976 result = fold_build2 (FLOOR_MOD_EXPR, operation_type, result,
977 convert (operation_type, modulus));
979 if (result_type && result_type != operation_type)
980 result = convert (result_type, result);
985 /* Similar, but for unary operations. */
988 build_unary_op (enum tree_code op_code, tree result_type, tree operand)
990 tree type = TREE_TYPE (operand);
991 tree base_type = get_base_type (type);
992 tree operation_type = result_type;
994 bool side_effects = false;
997 && TREE_CODE (operation_type) == RECORD_TYPE
998 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
999 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
1002 && !AGGREGATE_TYPE_P (operation_type)
1003 && TYPE_EXTRA_SUBTYPE_P (operation_type))
1004 operation_type = get_base_type (operation_type);
1010 if (!operation_type)
1011 result_type = operation_type = TREE_TYPE (type);
1013 gcc_assert (result_type == TREE_TYPE (type));
1015 result = fold_build1 (op_code, operation_type, operand);
1018 case TRUTH_NOT_EXPR:
1019 #ifdef ENABLE_CHECKING
1020 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
1022 result = invert_truthvalue_loc (EXPR_LOCATION (operand), operand);
1023 /* When not optimizing, fold the result as invert_truthvalue_loc
1024 doesn't fold the result of comparisons. This is intended to undo
1025 the trick used for boolean rvalues in gnat_to_gnu. */
1027 result = fold (result);
1030 case ATTR_ADDR_EXPR:
1032 switch (TREE_CODE (operand))
1035 case UNCONSTRAINED_ARRAY_REF:
1036 result = TREE_OPERAND (operand, 0);
1038 /* Make sure the type here is a pointer, not a reference.
1039 GCC wants pointer types for function addresses. */
1041 result_type = build_pointer_type (type);
1043 /* If the underlying object can alias everything, propagate the
1044 property since we are effectively retrieving the object. */
1045 if (POINTER_TYPE_P (TREE_TYPE (result))
1046 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1048 if (TREE_CODE (result_type) == POINTER_TYPE
1049 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1051 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1052 TYPE_MODE (result_type),
1054 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1055 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1057 = build_reference_type_for_mode (TREE_TYPE (result_type),
1058 TYPE_MODE (result_type),
1065 TREE_TYPE (result) = type = build_pointer_type (type);
1069 /* Fold a compound expression if it has unconstrained array type
1070 since the middle-end cannot handle it. But we don't it in the
1071 general case because it may introduce aliasing issues if the
1072 first operand is an indirect assignment and the second operand
1073 the corresponding address, e.g. for an allocator. */
1074 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
1076 result = build_unary_op (ADDR_EXPR, result_type,
1077 TREE_OPERAND (operand, 1));
1078 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1079 TREE_OPERAND (operand, 0), result);
1085 case ARRAY_RANGE_REF:
1088 /* If this is for 'Address, find the address of the prefix and add
1089 the offset to the field. Otherwise, do this the normal way. */
1090 if (op_code == ATTR_ADDR_EXPR)
1092 HOST_WIDE_INT bitsize;
1093 HOST_WIDE_INT bitpos;
1095 enum machine_mode mode;
1096 int unsignedp, volatilep;
1098 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1099 &mode, &unsignedp, &volatilep,
1102 /* If INNER is a padding type whose field has a self-referential
1103 size, convert to that inner type. We know the offset is zero
1104 and we need to have that type visible. */
1105 if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
1106 && CONTAINS_PLACEHOLDER_P
1107 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1108 (TREE_TYPE (inner))))))
1109 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1112 /* Compute the offset as a byte offset from INNER. */
1114 offset = size_zero_node;
1116 offset = size_binop (PLUS_EXPR, offset,
1117 size_int (bitpos / BITS_PER_UNIT));
1119 /* Take the address of INNER, convert the offset to void *, and
1120 add then. It will later be converted to the desired result
1122 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1123 inner = convert (ptr_void_type_node, inner);
1124 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1126 result = convert (build_pointer_type (TREE_TYPE (operand)),
1133 /* If this is just a constructor for a padded record, we can
1134 just take the address of the single field and convert it to
1135 a pointer to our type. */
1136 if (TYPE_IS_PADDING_P (type))
1138 result = VEC_index (constructor_elt,
1139 CONSTRUCTOR_ELTS (operand),
1141 result = convert (build_pointer_type (TREE_TYPE (operand)),
1142 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1149 if (AGGREGATE_TYPE_P (type)
1150 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1151 return build_unary_op (ADDR_EXPR, result_type,
1152 TREE_OPERAND (operand, 0));
1154 /* ... fallthru ... */
1156 case VIEW_CONVERT_EXPR:
1157 /* If this just a variant conversion or if the conversion doesn't
1158 change the mode, get the result type from this type and go down.
1159 This is needed for conversions of CONST_DECLs, to eventually get
1160 to the address of their CORRESPONDING_VARs. */
1161 if ((TYPE_MAIN_VARIANT (type)
1162 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1163 || (TYPE_MODE (type) != BLKmode
1164 && (TYPE_MODE (type)
1165 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1166 return build_unary_op (ADDR_EXPR,
1167 (result_type ? result_type
1168 : build_pointer_type (type)),
1169 TREE_OPERAND (operand, 0));
1173 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1175 /* ... fall through ... */
1180 /* If we are taking the address of a padded record whose field is
1181 contains a template, take the address of the template. */
1182 if (TYPE_IS_PADDING_P (type)
1183 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1184 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1186 type = TREE_TYPE (TYPE_FIELDS (type));
1187 operand = convert (type, operand);
1190 gnat_mark_addressable (operand);
1191 result = build_fold_addr_expr (operand);
1194 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1198 /* If we want to refer to an unconstrained array, use the appropriate
1199 expression to do so. This will never survive down to the back-end.
1200 But if TYPE is a thin pointer, first convert to a fat pointer. */
1201 if (TYPE_IS_THIN_POINTER_P (type)
1202 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1205 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1207 type = TREE_TYPE (operand);
1210 if (TYPE_IS_FAT_POINTER_P (type))
1212 result = build1 (UNCONSTRAINED_ARRAY_REF,
1213 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1214 TREE_READONLY (result)
1215 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1218 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1219 else if (TREE_CODE (operand) == ADDR_EXPR)
1220 result = TREE_OPERAND (operand, 0);
1222 /* Otherwise, build and fold the indirect reference. */
1225 result = build_fold_indirect_ref (operand);
1226 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1230 = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1236 tree modulus = ((operation_type
1237 && TREE_CODE (operation_type) == INTEGER_TYPE
1238 && TYPE_MODULAR_P (operation_type))
1239 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1240 int mod_pow2 = modulus && integer_pow2p (modulus);
1242 /* If this is a modular type, there are various possibilities
1243 depending on the operation and whether the modulus is a
1244 power of two or not. */
1248 gcc_assert (operation_type == base_type);
1249 operand = convert (operation_type, operand);
1251 /* The fastest in the negate case for binary modulus is
1252 the straightforward code; the TRUNC_MOD_EXPR below
1253 is an AND operation. */
1254 if (op_code == NEGATE_EXPR && mod_pow2)
1255 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1256 fold_build1 (NEGATE_EXPR, operation_type,
1260 /* For nonbinary negate case, return zero for zero operand,
1261 else return the modulus minus the operand. If the modulus
1262 is a power of two minus one, we can do the subtraction
1263 as an XOR since it is equivalent and faster on most machines. */
1264 else if (op_code == NEGATE_EXPR && !mod_pow2)
1266 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1268 convert (operation_type,
1269 integer_one_node))))
1270 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1273 result = fold_build2 (MINUS_EXPR, operation_type,
1276 result = fold_build3 (COND_EXPR, operation_type,
1277 fold_build2 (NE_EXPR,
1282 integer_zero_node)),
1287 /* For the NOT cases, we need a constant equal to
1288 the modulus minus one. For a binary modulus, we
1289 XOR against the constant and subtract the operand from
1290 that constant for nonbinary modulus. */
1292 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1293 convert (operation_type,
1297 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1300 result = fold_build2 (MINUS_EXPR, operation_type,
1308 /* ... fall through ... */
1311 gcc_assert (operation_type == base_type);
1312 result = fold_build1 (op_code, operation_type,
1313 convert (operation_type, operand));
1318 TREE_SIDE_EFFECTS (result) = 1;
1319 if (TREE_CODE (result) == INDIRECT_REF)
1320 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1323 if (result_type && TREE_TYPE (result) != result_type)
1324 result = convert (result_type, result);
1329 /* Similar, but for COND_EXPR. */
1332 build_cond_expr (tree result_type, tree condition_operand,
1333 tree true_operand, tree false_operand)
1335 bool addr_p = false;
1338 /* The front-end verified that result, true and false operands have
1339 same base type. Convert everything to the result type. */
1340 true_operand = convert (result_type, true_operand);
1341 false_operand = convert (result_type, false_operand);
1343 /* If the result type is unconstrained, take the address of the operands and
1344 then dereference the result. Likewise if the result type is passed by
1345 reference, but this is natively handled in the gimplifier. */
1346 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1347 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1349 result_type = build_pointer_type (result_type);
1350 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1351 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1355 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1356 true_operand, false_operand);
1358 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1359 in both arms, make sure it gets evaluated by moving it ahead of the
1360 conditional expression. This is necessary because it is evaluated
1361 in only one place at run time and would otherwise be uninitialized
1362 in one of the arms. */
1363 true_operand = skip_simple_arithmetic (true_operand);
1364 false_operand = skip_simple_arithmetic (false_operand);
1366 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1367 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1370 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1375 /* Similar, but for COMPOUND_EXPR. */
1378 build_compound_expr (tree result_type, tree stmt_operand, tree expr_operand)
1380 bool addr_p = false;
1383 /* If the result type is unconstrained, take the address of the operand and
1384 then dereference the result. Likewise if the result type is passed by
1385 reference, but this is natively handled in the gimplifier. */
1386 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1387 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1389 result_type = build_pointer_type (result_type);
1390 expr_operand = build_unary_op (ADDR_EXPR, result_type, expr_operand);
1394 result = fold_build2 (COMPOUND_EXPR, result_type, stmt_operand,
1398 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1402 /* Similar, but for RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR
1403 around the assignment of RET_VAL to RET_OBJ. Otherwise just build a bare
1404 RETURN_EXPR around RESULT_OBJ, which may be null in this case. */
1407 build_return_expr (tree ret_obj, tree ret_val)
1413 /* The gimplifier explicitly enforces the following invariant:
1422 As a consequence, type consistency dictates that we use the type
1423 of the RET_OBJ as the operation type. */
1424 tree operation_type = TREE_TYPE (ret_obj);
1426 /* Convert the right operand to the operation type. Note that it's the
1427 same transformation as in the MODIFY_EXPR case of build_binary_op,
1428 with the assumption that the type cannot involve a placeholder. */
1429 if (operation_type != TREE_TYPE (ret_val))
1430 ret_val = convert (operation_type, ret_val);
1432 result_expr = build2 (MODIFY_EXPR, operation_type, ret_obj, ret_val);
1435 result_expr = ret_obj;
1437 return build1 (RETURN_EXPR, void_type_node, result_expr);
1440 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1444 build_call_1_expr (tree fundecl, tree arg)
1446 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1447 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1449 TREE_SIDE_EFFECTS (call) = 1;
1453 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1457 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1459 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1460 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1462 TREE_SIDE_EFFECTS (call) = 1;
1466 /* Likewise to call FUNDECL with no arguments. */
1469 build_call_0_expr (tree fundecl)
1471 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1472 it possible to propagate DECL_IS_PURE on parameterless functions. */
1473 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1474 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1479 /* Call a function that raises an exception and pass the line number and file
1480 name, if requested. MSG says which exception function to call.
1482 GNAT_NODE is the gnat node conveying the source location for which the
1483 error should be signaled, or Empty in which case the error is signaled on
1484 the current ref_file_name/input_line.
1486 KIND says which kind of exception this is for
1487 (N_Raise_{Constraint,Storage,Program}_Error). */
1490 build_call_raise (int msg, Node_Id gnat_node, char kind)
1492 tree fndecl = gnat_raise_decls[msg];
1493 tree label = get_exception_label (kind);
1499 /* If this is to be done as a goto, handle that case. */
1502 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1503 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1505 /* If Local_Raise is present, generate
1506 Local_Raise (exception'Identity); */
1507 if (Present (local_raise))
1509 tree gnu_local_raise
1510 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1511 tree gnu_exception_entity
1512 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1514 = build_call_1_expr (gnu_local_raise,
1515 build_unary_op (ADDR_EXPR, NULL_TREE,
1516 gnu_exception_entity));
1518 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1519 gnu_call, gnu_result);}
1525 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1527 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1528 ? IDENTIFIER_POINTER
1529 (get_identifier (Get_Name_String
1531 (Get_Source_File_Index (Sloc (gnat_node))))))
1535 filename = build_string (len, str);
1537 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1538 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1540 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1541 build_index_type (size_int (len)));
1544 build_call_2_expr (fndecl,
1546 build_pointer_type (unsigned_char_type_node),
1548 build_int_cst (NULL_TREE, line_number));
1551 /* Similar to build_call_raise, for an index or range check exception as
1552 determined by MSG, with extra information generated of the form
1553 "INDEX out of range FIRST..LAST". */
1556 build_call_raise_range (int msg, Node_Id gnat_node,
1557 tree index, tree first, tree last)
1560 tree fndecl = gnat_raise_decls_ext[msg];
1562 int line_number, column_number;
1567 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1569 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1570 ? IDENTIFIER_POINTER
1571 (get_identifier (Get_Name_String
1573 (Get_Source_File_Index (Sloc (gnat_node))))))
1577 filename = build_string (len, str);
1578 if (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1580 line_number = Get_Logical_Line_Number (Sloc (gnat_node));
1581 column_number = Get_Column_Number (Sloc (gnat_node));
1585 line_number = input_line;
1589 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1590 build_index_type (size_int (len)));
1592 call = build_call_nary (TREE_TYPE (TREE_TYPE (fndecl)),
1593 build_unary_op (ADDR_EXPR, NULL_TREE, fndecl),
1596 build_pointer_type (unsigned_char_type_node),
1598 build_int_cst (NULL_TREE, line_number),
1599 build_int_cst (NULL_TREE, column_number),
1600 convert (integer_type_node, index),
1601 convert (integer_type_node, first),
1602 convert (integer_type_node, last));
1603 TREE_SIDE_EFFECTS (call) = 1;
1607 /* Similar to build_call_raise, with extra information about the column
1608 where the check failed. */
1611 build_call_raise_column (int msg, Node_Id gnat_node)
1613 tree fndecl = gnat_raise_decls_ext[msg];
1616 int line_number, column_number;
1621 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1623 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1624 ? IDENTIFIER_POINTER
1625 (get_identifier (Get_Name_String
1627 (Get_Source_File_Index (Sloc (gnat_node))))))
1631 filename = build_string (len, str);
1632 if (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1634 line_number = Get_Logical_Line_Number (Sloc (gnat_node));
1635 column_number = Get_Column_Number (Sloc (gnat_node));
1639 line_number = input_line;
1643 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1644 build_index_type (size_int (len)));
1646 call = build_call_nary (TREE_TYPE (TREE_TYPE (fndecl)),
1647 build_unary_op (ADDR_EXPR, NULL_TREE, fndecl),
1650 build_pointer_type (unsigned_char_type_node),
1652 build_int_cst (NULL_TREE, line_number),
1653 build_int_cst (NULL_TREE, column_number));
1654 TREE_SIDE_EFFECTS (call) = 1;
1658 /* qsort comparer for the bit positions of two constructor elements
1659 for record components. */
1662 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1664 const constructor_elt * const elmt1 = (const constructor_elt const *) rt1;
1665 const constructor_elt * const elmt2 = (const constructor_elt const *) rt2;
1666 const_tree const field1 = elmt1->index;
1667 const_tree const field2 = elmt2->index;
1669 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1671 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1674 /* Return a CONSTRUCTOR of TYPE whose elements are V. */
1677 gnat_build_constructor (tree type, VEC(constructor_elt,gc) *v)
1679 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1680 bool side_effects = false;
1681 tree result, obj, val;
1682 unsigned int n_elmts;
1684 /* Scan the elements to see if they are all constant or if any has side
1685 effects, to let us set global flags on the resulting constructor. Count
1686 the elements along the way for possible sorting purposes below. */
1687 FOR_EACH_CONSTRUCTOR_ELT (v, n_elmts, obj, val)
1689 /* The predicate must be in keeping with output_constructor. */
1690 if (!TREE_CONSTANT (val)
1691 || (TREE_CODE (type) == RECORD_TYPE
1692 && CONSTRUCTOR_BITFIELD_P (obj)
1693 && !initializer_constant_valid_for_bitfield_p (val))
1694 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1695 allconstant = false;
1697 if (TREE_SIDE_EFFECTS (val))
1698 side_effects = true;
1701 /* For record types with constant components only, sort field list
1702 by increasing bit position. This is necessary to ensure the
1703 constructor can be output as static data. */
1704 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1705 VEC_qsort (constructor_elt, v, compare_elmt_bitpos);
1707 result = build_constructor (type, v);
1708 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1709 TREE_SIDE_EFFECTS (result) = side_effects;
1710 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1714 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1715 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1716 for the field. Don't fold the result if NO_FOLD_P is true.
1718 We also handle the fact that we might have been passed a pointer to the
1719 actual record and know how to look for fields in variant parts. */
1722 build_simple_component_ref (tree record_variable, tree component,
1723 tree field, bool no_fold_p)
1725 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1726 tree ref, inner_variable;
1728 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1729 || TREE_CODE (record_type) == UNION_TYPE
1730 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1731 && TYPE_SIZE (record_type)
1732 && (component != 0) != (field != 0));
1734 /* If no field was specified, look for a field with the specified name
1735 in the current record only. */
1737 for (field = TYPE_FIELDS (record_type); field;
1738 field = TREE_CHAIN (field))
1739 if (DECL_NAME (field) == component)
1745 /* If this field is not in the specified record, see if we can find a field
1746 in the specified record whose original field is the same as this one. */
1747 if (DECL_CONTEXT (field) != record_type)
1751 /* First loop thru normal components. */
1752 for (new_field = TYPE_FIELDS (record_type); new_field;
1753 new_field = DECL_CHAIN (new_field))
1754 if (SAME_FIELD_P (field, new_field))
1757 /* Next, see if we're looking for an inherited component in an extension.
1758 If so, look thru the extension directly. */
1760 && TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1761 && TYPE_ALIGN_OK (record_type)
1762 && TREE_CODE (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1764 && TYPE_ALIGN_OK (TREE_TYPE (TREE_OPERAND (record_variable, 0))))
1766 ref = build_simple_component_ref (TREE_OPERAND (record_variable, 0),
1767 NULL_TREE, field, no_fold_p);
1772 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1773 the component in the first search. Doing this search in 2 steps
1774 is required to avoiding hidden homonymous fields in the
1777 for (new_field = TYPE_FIELDS (record_type); new_field;
1778 new_field = DECL_CHAIN (new_field))
1779 if (DECL_INTERNAL_P (new_field))
1782 = build_simple_component_ref (record_variable,
1783 NULL_TREE, new_field, no_fold_p);
1784 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1797 /* If the field's offset has overflowed, do not attempt to access it
1798 as doing so may trigger sanity checks deeper in the back-end.
1799 Note that we don't need to warn since this will be done on trying
1800 to declare the object. */
1801 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1802 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1805 /* Look through conversion between type variants. Note that this
1806 is transparent as far as the field is concerned. */
1807 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1808 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1810 inner_variable = TREE_OPERAND (record_variable, 0);
1812 inner_variable = record_variable;
1814 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1817 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1818 TREE_READONLY (ref) = 1;
1819 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1820 || TYPE_VOLATILE (record_type))
1821 TREE_THIS_VOLATILE (ref) = 1;
1826 /* The generic folder may punt in this case because the inner array type
1827 can be self-referential, but folding is in fact not problematic. */
1828 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1829 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1831 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1832 unsigned HOST_WIDE_INT idx;
1834 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1844 /* Like build_simple_component_ref, except that we give an error if the
1845 reference could not be found. */
1848 build_component_ref (tree record_variable, tree component,
1849 tree field, bool no_fold_p)
1851 tree ref = build_simple_component_ref (record_variable, component, field,
1857 /* If FIELD was specified, assume this is an invalid user field so raise
1858 Constraint_Error. Otherwise, we have no type to return so abort. */
1860 return build1 (NULL_EXPR, TREE_TYPE (field),
1861 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1862 N_Raise_Constraint_Error));
1865 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1866 identically. Process the case where a GNAT_PROC to call is provided. */
1869 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1870 Entity_Id gnat_proc, Entity_Id gnat_pool)
1872 tree gnu_proc = gnat_to_gnu (gnat_proc);
1873 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1876 /* The storage pools are obviously always tagged types, but the
1877 secondary stack uses the same mechanism and is not tagged. */
1878 if (Is_Tagged_Type (Etype (gnat_pool)))
1880 /* The size is the third parameter; the alignment is the
1882 Entity_Id gnat_size_type
1883 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1884 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1886 tree gnu_pool = gnat_to_gnu (gnat_pool);
1887 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1888 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1890 gnu_size = convert (gnu_size_type, gnu_size);
1891 gnu_align = convert (gnu_size_type, gnu_align);
1893 /* The first arg is always the address of the storage pool; next
1894 comes the address of the object, for a deallocator, then the
1895 size and alignment. */
1897 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1898 gnu_proc_addr, 4, gnu_pool_addr,
1899 gnu_obj, gnu_size, gnu_align);
1901 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1902 gnu_proc_addr, 3, gnu_pool_addr,
1903 gnu_size, gnu_align);
1906 /* Secondary stack case. */
1909 /* The size is the second parameter. */
1910 Entity_Id gnat_size_type
1911 = Etype (Next_Formal (First_Formal (gnat_proc)));
1912 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1914 gnu_size = convert (gnu_size_type, gnu_size);
1916 /* The first arg is the address of the object, for a deallocator,
1919 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1920 gnu_proc_addr, 2, gnu_obj, gnu_size);
1922 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1923 gnu_proc_addr, 1, gnu_size);
1926 TREE_SIDE_EFFECTS (gnu_call) = 1;
1930 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1931 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1932 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1936 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1938 /* When the DATA_TYPE alignment is stricter than what malloc offers
1939 (super-aligned case), we allocate an "aligning" wrapper type and return
1940 the address of its single data field with the malloc's return value
1941 stored just in front. */
1943 unsigned int data_align = TYPE_ALIGN (data_type);
1944 unsigned int default_allocator_alignment
1945 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1948 = ((data_align > default_allocator_alignment)
1949 ? make_aligning_type (data_type, data_align, data_size,
1950 default_allocator_alignment,
1951 POINTER_SIZE / BITS_PER_UNIT)
1955 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1959 /* On VMS, if pointers are 64-bit and the allocator size is 32-bit or
1960 Convention C, allocate 32-bit memory. */
1961 if (TARGET_ABI_OPEN_VMS
1962 && POINTER_SIZE == 64
1963 && Nkind (gnat_node) == N_Allocator
1964 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1965 || Convention (Etype (gnat_node)) == Convention_C))
1966 malloc_ptr = build_call_1_expr (malloc32_decl, size_to_malloc);
1968 malloc_ptr = build_call_1_expr (malloc_decl, size_to_malloc);
1972 /* Latch malloc's return value and get a pointer to the aligning field
1974 tree storage_ptr = gnat_protect_expr (malloc_ptr);
1976 tree aligning_record_addr
1977 = convert (build_pointer_type (aligning_type), storage_ptr);
1979 tree aligning_record
1980 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1983 = build_component_ref (aligning_record, NULL_TREE,
1984 TYPE_FIELDS (aligning_type), false);
1986 tree aligning_field_addr
1987 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1989 /* Then arrange to store the allocator's return value ahead
1991 tree storage_ptr_slot_addr
1992 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1993 convert (ptr_void_type_node, aligning_field_addr),
1994 size_int (-(HOST_WIDE_INT) POINTER_SIZE
1997 tree storage_ptr_slot
1998 = build_unary_op (INDIRECT_REF, NULL_TREE,
1999 convert (build_pointer_type (ptr_void_type_node),
2000 storage_ptr_slot_addr));
2003 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
2004 build_binary_op (MODIFY_EXPR, NULL_TREE,
2005 storage_ptr_slot, storage_ptr),
2006 aligning_field_addr);
2012 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
2013 designated by DATA_PTR using the __gnat_free entry point. */
2016 maybe_wrap_free (tree data_ptr, tree data_type)
2018 /* In the regular alignment case, we pass the data pointer straight to free.
2019 In the superaligned case, we need to retrieve the initial allocator
2020 return value, stored in front of the data block at allocation time. */
2022 unsigned int data_align = TYPE_ALIGN (data_type);
2023 unsigned int default_allocator_alignment
2024 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
2028 if (data_align > default_allocator_alignment)
2030 /* DATA_FRONT_PTR (void *)
2031 = (void *)DATA_PTR - (void *)sizeof (void *)) */
2034 (POINTER_PLUS_EXPR, ptr_void_type_node,
2035 convert (ptr_void_type_node, data_ptr),
2036 size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
2038 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
2041 (INDIRECT_REF, NULL_TREE,
2042 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
2045 free_ptr = data_ptr;
2047 return build_call_1_expr (free_decl, free_ptr);
2050 /* Build a GCC tree to call an allocation or deallocation function.
2051 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
2052 generate an allocator.
2054 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
2055 object type, used to determine the to-be-honored address alignment.
2056 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
2057 pool to use. If not present, malloc and free are used. GNAT_NODE is used
2058 to provide an error location for restriction violation messages. */
2061 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
2062 Entity_Id gnat_proc, Entity_Id gnat_pool,
2065 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
2067 /* Explicit proc to call ? This one is assumed to deal with the type
2068 alignment constraints. */
2069 if (Present (gnat_proc))
2070 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
2071 gnat_proc, gnat_pool);
2073 /* Otherwise, object to "free" or "malloc" with possible special processing
2074 for alignments stricter than what the default allocator honors. */
2076 return maybe_wrap_free (gnu_obj, gnu_type);
2079 /* Assert that we no longer can be called with this special pool. */
2080 gcc_assert (gnat_pool != -1);
2082 /* Check that we aren't violating the associated restriction. */
2083 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
2084 Check_No_Implicit_Heap_Alloc (gnat_node);
2086 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
2090 /* Build a GCC tree to correspond to allocating an object of TYPE whose
2091 initial value is INIT, if INIT is nonzero. Convert the expression to
2092 RESULT_TYPE, which must be some type of pointer. Return the tree.
2094 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
2095 the storage pool to use. GNAT_NODE is used to provide an error
2096 location for restriction violation messages. If IGNORE_INIT_TYPE is
2097 true, ignore the type of INIT for the purpose of determining the size;
2098 this will cause the maximum size to be allocated if TYPE is of
2099 self-referential size. */
2102 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
2103 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
2105 tree size = TYPE_SIZE_UNIT (type);
2108 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
2109 if (init && TREE_CODE (init) == NULL_EXPR)
2110 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
2112 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
2113 sizes of the object and its template. Allocate the whole thing and
2114 fill in the parts that are known. */
2115 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
2118 = build_unc_object_type_from_ptr (result_type, type,
2119 get_identifier ("ALLOC"), false);
2120 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
2121 tree storage_ptr_type = build_pointer_type (storage_type);
2124 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2127 /* If the size overflows, pass -1 so the allocator will raise
2129 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2130 size = ssize_int (-1);
2132 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2133 gnat_proc, gnat_pool, gnat_node);
2134 storage = convert (storage_ptr_type, gnat_protect_expr (storage));
2136 if (TYPE_IS_PADDING_P (type))
2138 type = TREE_TYPE (TYPE_FIELDS (type));
2140 init = convert (type, init);
2143 /* If there is an initializing expression, make a constructor for
2144 the entire object including the bounds and copy it into the
2145 object. If there is no initializing expression, just set the
2149 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, 2);
2151 CONSTRUCTOR_APPEND_ELT (v, TYPE_FIELDS (storage_type),
2152 build_template (template_type, type, init));
2153 CONSTRUCTOR_APPEND_ELT (v, DECL_CHAIN (TYPE_FIELDS (storage_type)),
2158 build2 (COMPOUND_EXPR, storage_ptr_type,
2160 (MODIFY_EXPR, storage_type,
2161 build_unary_op (INDIRECT_REF, NULL_TREE,
2162 convert (storage_ptr_type, storage)),
2163 gnat_build_constructor (storage_type, v)),
2164 convert (storage_ptr_type, storage)));
2168 (COMPOUND_EXPR, result_type,
2170 (MODIFY_EXPR, template_type,
2172 (build_unary_op (INDIRECT_REF, NULL_TREE,
2173 convert (storage_ptr_type, storage)),
2174 NULL_TREE, TYPE_FIELDS (storage_type), false),
2175 build_template (template_type, type, NULL_TREE)),
2176 convert (result_type, convert (storage_ptr_type, storage)));
2179 /* If we have an initializing expression, see if its size is simpler
2180 than the size from the type. */
2181 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2182 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2183 || CONTAINS_PLACEHOLDER_P (size)))
2184 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2186 /* If the size is still self-referential, reference the initializing
2187 expression, if it is present. If not, this must have been a
2188 call to allocate a library-level object, in which case we use
2189 the maximum size. */
2190 if (CONTAINS_PLACEHOLDER_P (size))
2192 if (!ignore_init_type && init)
2193 size = substitute_placeholder_in_expr (size, init);
2195 size = max_size (size, true);
2198 /* If the size overflows, pass -1 so the allocator will raise
2200 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2201 size = ssize_int (-1);
2203 result = convert (result_type,
2204 build_call_alloc_dealloc (NULL_TREE, size, type,
2205 gnat_proc, gnat_pool,
2208 /* If we have an initial value, protect the new address, assign the value
2209 and return the address with a COMPOUND_EXPR. */
2212 result = gnat_protect_expr (result);
2214 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2216 (MODIFY_EXPR, NULL_TREE,
2217 build_unary_op (INDIRECT_REF,
2218 TREE_TYPE (TREE_TYPE (result)), result),
2223 return convert (result_type, result);
2226 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2227 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2228 how we derive the source location to raise C_E on an out of range
2232 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2234 tree parm_decl = get_gnu_tree (gnat_formal);
2235 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2237 const bool do_range_check
2239 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2240 VEC(constructor_elt,gc) *v = NULL;
2242 expr = maybe_unconstrained_array (expr);
2243 gnat_mark_addressable (expr);
2245 for (field = TYPE_FIELDS (record_type); field; field = DECL_CHAIN (field))
2247 tree conexpr = convert (TREE_TYPE (field),
2248 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2249 (DECL_INITIAL (field), expr));
2251 /* Check to ensure that only 32-bit pointers are passed in
2252 32-bit descriptors */
2254 && strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2257 = build_pointer_type_for_mode (void_type_node, DImode, false);
2258 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2260 = build_int_cstu (long_integer_type_node, 0x80000000);
2262 add_stmt (build3 (COND_EXPR, void_type_node,
2263 build_binary_op (GE_EXPR, boolean_type_node,
2264 convert (long_integer_type_node,
2267 build_call_raise (CE_Range_Check_Failed,
2269 N_Raise_Constraint_Error),
2272 CONSTRUCTOR_APPEND_ELT (v, field, conexpr);
2275 return gnat_build_constructor (record_type, v);
2278 /* Indicate that we need to take the address of T and that it therefore
2279 should not be allocated in a register. Returns true if successful. */
2282 gnat_mark_addressable (tree t)
2285 switch (TREE_CODE (t))
2290 case ARRAY_RANGE_REF:
2293 case VIEW_CONVERT_EXPR:
2294 case NON_LVALUE_EXPR:
2296 t = TREE_OPERAND (t, 0);
2300 t = TREE_OPERAND (t, 1);
2304 TREE_ADDRESSABLE (t) = 1;
2310 TREE_ADDRESSABLE (t) = 1;
2314 TREE_ADDRESSABLE (t) = 1;
2318 return DECL_CONST_CORRESPONDING_VAR (t)
2319 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
2326 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2327 but we know how to handle our own nodes. */
2330 gnat_save_expr (tree exp)
2332 tree type = TREE_TYPE (exp);
2333 enum tree_code code = TREE_CODE (exp);
2335 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2338 if (code == UNCONSTRAINED_ARRAY_REF)
2340 tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
2341 TREE_READONLY (t) = TYPE_READONLY (type);
2345 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2346 This may be more efficient, but will also allow us to more easily find
2347 the match for the PLACEHOLDER_EXPR. */
2348 if (code == COMPONENT_REF
2349 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2350 return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
2351 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2353 return save_expr (exp);
2356 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2357 is optimized under the assumption that EXP's value doesn't change before
2358 its subsequent reuse(s) except through its potential reevaluation. */
2361 gnat_protect_expr (tree exp)
2363 tree type = TREE_TYPE (exp);
2364 enum tree_code code = TREE_CODE (exp);
2366 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2369 /* If EXP has no side effects, we theoritically don't need to do anything.
2370 However, we may be recursively passed more and more complex expressions
2371 involving checks which will be reused multiple times and eventually be
2372 unshared for gimplification; in order to avoid a complexity explosion
2373 at that point, we protect any expressions more complex than a simple
2374 arithmetic expression. */
2375 if (!TREE_SIDE_EFFECTS (exp))
2377 tree inner = skip_simple_arithmetic (exp);
2378 if (!EXPR_P (inner) || REFERENCE_CLASS_P (inner))
2382 /* If this is a conversion, protect what's inside the conversion. */
2383 if (code == NON_LVALUE_EXPR
2384 || CONVERT_EXPR_CODE_P (code)
2385 || code == VIEW_CONVERT_EXPR)
2386 return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2388 /* If we're indirectly referencing something, we only need to protect the
2389 address since the data itself can't change in these situations. */
2390 if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
2392 tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2393 TREE_READONLY (t) = TYPE_READONLY (type);
2397 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2398 This may be more efficient, but will also allow us to more easily find
2399 the match for the PLACEHOLDER_EXPR. */
2400 if (code == COMPONENT_REF
2401 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2402 return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
2403 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2405 /* If this is a fat pointer or something that can be placed in a register,
2406 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2407 returned via invisible reference in most ABIs so the temporary will
2408 directly be filled by the callee. */
2409 if (TYPE_IS_FAT_POINTER_P (type)
2410 || TYPE_MODE (type) != BLKmode
2411 || code == CALL_EXPR)
2412 return save_expr (exp);
2414 /* Otherwise reference, protect the address and dereference. */
2416 build_unary_op (INDIRECT_REF, type,
2417 save_expr (build_unary_op (ADDR_EXPR,
2418 build_reference_type (type),
2422 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2423 argument to force evaluation of everything. */
2426 gnat_stabilize_reference_1 (tree e, bool force)
2428 enum tree_code code = TREE_CODE (e);
2429 tree type = TREE_TYPE (e);
2432 /* We cannot ignore const expressions because it might be a reference
2433 to a const array but whose index contains side-effects. But we can
2434 ignore things that are actual constant or that already have been
2435 handled by this function. */
2436 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2439 switch (TREE_CODE_CLASS (code))
2441 case tcc_exceptional:
2442 case tcc_declaration:
2443 case tcc_comparison:
2444 case tcc_expression:
2447 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2448 fat pointer. This may be more efficient, but will also allow
2449 us to more easily find the match for the PLACEHOLDER_EXPR. */
2450 if (code == COMPONENT_REF
2451 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
2453 = build3 (code, type,
2454 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2455 TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
2456 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2457 so that it will only be evaluated once. */
2458 /* The tcc_reference and tcc_comparison classes could be handled as
2459 below, but it is generally faster to only evaluate them once. */
2460 else if (TREE_SIDE_EFFECTS (e) || force)
2461 return save_expr (e);
2467 /* Recursively stabilize each operand. */
2469 = build2 (code, type,
2470 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2471 gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
2475 /* Recursively stabilize each operand. */
2477 = build1 (code, type,
2478 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
2485 /* See similar handling in gnat_stabilize_reference. */
2486 TREE_READONLY (result) = TREE_READONLY (e);
2487 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
2488 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2490 if (code == INDIRECT_REF || code == ARRAY_REF || code == ARRAY_RANGE_REF)
2491 TREE_THIS_NOTRAP (result) = TREE_THIS_NOTRAP (e);
2496 /* This is equivalent to stabilize_reference in tree.c but we know how to
2497 handle our own nodes and we take extra arguments. FORCE says whether to
2498 force evaluation of everything. We set SUCCESS to true unless we walk
2499 through something we don't know how to stabilize. */
2502 gnat_stabilize_reference (tree ref, bool force, bool *success)
2504 tree type = TREE_TYPE (ref);
2505 enum tree_code code = TREE_CODE (ref);
2508 /* Assume we'll success unless proven otherwise. */
2518 /* No action is needed in this case. */
2524 case FIX_TRUNC_EXPR:
2525 case VIEW_CONVERT_EXPR:
2527 = build1 (code, type,
2528 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2533 case UNCONSTRAINED_ARRAY_REF:
2534 result = build1 (code, type,
2535 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
2540 result = build3 (COMPONENT_REF, type,
2541 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2543 TREE_OPERAND (ref, 1), NULL_TREE);
2547 result = build3 (BIT_FIELD_REF, type,
2548 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2550 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2552 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
2557 case ARRAY_RANGE_REF:
2558 result = build4 (code, type,
2559 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2561 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2563 NULL_TREE, NULL_TREE);
2567 result = gnat_stabilize_reference_1 (ref, force);
2571 result = build2 (COMPOUND_EXPR, type,
2572 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2574 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2579 /* Constructors with 1 element are used extensively to formally
2580 convert objects to special wrapping types. */
2581 if (TREE_CODE (type) == RECORD_TYPE
2582 && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
2585 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
2587 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
2589 = build_constructor_single (type, index,
2590 gnat_stabilize_reference_1 (value,
2602 ref = error_mark_node;
2604 /* ... fall through to failure ... */
2606 /* If arg isn't a kind of lvalue we recognize, make no change.
2607 Caller should recognize the error for an invalid lvalue. */
2614 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2615 may not be sustained across some paths, such as the way via build1 for
2616 INDIRECT_REF. We reset those flags here in the general case, which is
2617 consistent with the GCC version of this routine.
2619 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2620 paths introduce side-effects where there was none initially (e.g. if a
2621 SAVE_EXPR is built) and we also want to keep track of that. */
2622 TREE_READONLY (result) = TREE_READONLY (ref);
2623 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
2624 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);