1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2011, 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 to 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 avoid writing more than what the target can hold if this is for
197 an assignment and the case of tagged types is handled in build_binary_op
198 so we use the lhs type if it is known to be smaller or of constant size
199 and 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 an assignment, except for the case of record types with a variant
202 part on the lhs but not on the rhs to make the conversion simpler. */
203 if (TREE_CONSTANT (TYPE_SIZE (t1))
204 && (!TREE_CONSTANT (TYPE_SIZE (t2))
205 || tree_int_cst_lt (TYPE_SIZE (t1), TYPE_SIZE (t2))
206 || (TYPE_SIZE (t1) == TYPE_SIZE (t2)
207 && !(TREE_CODE (t1) == RECORD_TYPE
208 && TREE_CODE (t2) == RECORD_TYPE
209 && get_variant_part (t1) != NULL_TREE
210 && get_variant_part (t2) == NULL_TREE))))
213 /* Otherwise, if the lhs type is non-BLKmode, use it. Note that we know
214 that we will not have any alignment problems since, if we did, the
215 non-BLKmode type could not have been used. */
216 if (TYPE_MODE (t1) != BLKmode)
219 /* If the rhs type is of constant size, use it whatever the modes. At
220 this point it is known to be smaller, or of constant size and the
222 if (TREE_CONSTANT (TYPE_SIZE (t2)))
225 /* Otherwise, if the rhs type is non-BLKmode, use it. */
226 if (TYPE_MODE (t2) != BLKmode)
229 /* In this case, both types have variable size and BLKmode. It's
230 probably best to leave the "type mismatch" because changing it
231 could cause a bad self-referential reference. */
235 /* Return an expression tree representing an equality comparison of A1 and A2,
236 two objects of type ARRAY_TYPE. The result should be of type RESULT_TYPE.
238 Two arrays are equal in one of two ways: (1) if both have zero length in
239 some dimension (not necessarily the same dimension) or (2) if the lengths
240 in each dimension are equal and the data is equal. We perform the length
241 tests in as efficient a manner as possible. */
244 compare_arrays (location_t loc, tree result_type, tree a1, tree a2)
246 tree result = convert (result_type, boolean_true_node);
247 tree a1_is_null = convert (result_type, boolean_false_node);
248 tree a2_is_null = convert (result_type, boolean_false_node);
249 tree t1 = TREE_TYPE (a1);
250 tree t2 = TREE_TYPE (a2);
251 bool a1_side_effects_p = TREE_SIDE_EFFECTS (a1);
252 bool a2_side_effects_p = TREE_SIDE_EFFECTS (a2);
253 bool length_zero_p = false;
255 /* If either operand has side-effects, they have to be evaluated only once
256 in spite of the multiple references to the operand in the comparison. */
257 if (a1_side_effects_p)
258 a1 = gnat_protect_expr (a1);
260 if (a2_side_effects_p)
261 a2 = gnat_protect_expr (a2);
263 /* Process each dimension separately and compare the lengths. If any
264 dimension has a length known to be zero, set LENGTH_ZERO_P to true
265 in order to suppress the comparison of the data at the end. */
266 while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
268 tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
269 tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
270 tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
271 tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
272 tree length1 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub1, lb1),
274 tree length2 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub2, lb2),
276 tree comparison, this_a1_is_null, this_a2_is_null;
278 /* If the length of the first array is a constant, swap our operands
279 unless the length of the second array is the constant zero. */
280 if (TREE_CODE (length1) == INTEGER_CST && !integer_zerop (length2))
285 tem = a1, a1 = a2, a2 = tem;
286 tem = t1, t1 = t2, t2 = tem;
287 tem = lb1, lb1 = lb2, lb2 = tem;
288 tem = ub1, ub1 = ub2, ub2 = tem;
289 tem = length1, length1 = length2, length2 = tem;
290 tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
291 btem = a1_side_effects_p, a1_side_effects_p = a2_side_effects_p,
292 a2_side_effects_p = btem;
295 /* If the length of the second array is the constant zero, we can just
296 use the original stored bounds for the first array and see whether
297 last < first holds. */
298 if (integer_zerop (length2))
300 length_zero_p = true;
302 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
303 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
305 comparison = fold_build2_loc (loc, LT_EXPR, result_type, ub1, lb1);
306 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
307 if (EXPR_P (comparison))
308 SET_EXPR_LOCATION (comparison, loc);
310 this_a1_is_null = comparison;
311 this_a2_is_null = convert (result_type, boolean_true_node);
314 /* Otherwise, if the length is some other constant value, we know that
315 this dimension in the second array cannot be superflat, so we can
316 just use its length computed from the actual stored bounds. */
317 else if (TREE_CODE (length2) == INTEGER_CST)
321 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
322 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
323 /* Note that we know that UB2 and LB2 are constant and hence
324 cannot contain a PLACEHOLDER_EXPR. */
325 ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
326 lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
327 bt = get_base_type (TREE_TYPE (ub1));
330 = fold_build2_loc (loc, EQ_EXPR, result_type,
331 build_binary_op (MINUS_EXPR, bt, ub1, lb1),
332 build_binary_op (MINUS_EXPR, bt, ub2, lb2));
333 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
334 if (EXPR_P (comparison))
335 SET_EXPR_LOCATION (comparison, loc);
338 = fold_build2_loc (loc, LT_EXPR, result_type, ub1, lb1);
340 this_a2_is_null = convert (result_type, boolean_false_node);
343 /* Otherwise, compare the computed lengths. */
346 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
347 length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
350 = fold_build2_loc (loc, EQ_EXPR, result_type, length1, length2);
352 /* If the length expression is of the form (cond ? val : 0), assume
353 that cond is equivalent to (length != 0). That's guaranteed by
354 construction of the array types in gnat_to_gnu_entity. */
355 if (TREE_CODE (length1) == COND_EXPR
356 && integer_zerop (TREE_OPERAND (length1, 2)))
358 = invert_truthvalue_loc (loc, TREE_OPERAND (length1, 0));
360 this_a1_is_null = fold_build2_loc (loc, EQ_EXPR, result_type,
361 length1, size_zero_node);
363 /* Likewise for the second array. */
364 if (TREE_CODE (length2) == COND_EXPR
365 && integer_zerop (TREE_OPERAND (length2, 2)))
367 = invert_truthvalue_loc (loc, TREE_OPERAND (length2, 0));
369 this_a2_is_null = fold_build2_loc (loc, EQ_EXPR, result_type,
370 length2, size_zero_node);
373 /* Append expressions for this dimension to the final expressions. */
374 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
377 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
378 this_a1_is_null, a1_is_null);
380 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
381 this_a2_is_null, a2_is_null);
387 /* Unless the length of some dimension is known to be zero, compare the
388 data in the array. */
391 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
396 a1 = convert (type, a1),
397 a2 = convert (type, a2);
400 comparison = fold_build2_loc (loc, EQ_EXPR, result_type, a1, a2);
403 = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result, comparison);
406 /* The result is also true if both sizes are zero. */
407 result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
408 build_binary_op (TRUTH_ANDIF_EXPR, result_type,
409 a1_is_null, a2_is_null),
412 /* If either operand has side-effects, they have to be evaluated before
413 starting the comparison above since the place they would be otherwise
414 evaluated could be wrong. */
415 if (a1_side_effects_p)
416 result = build2 (COMPOUND_EXPR, result_type, a1, result);
418 if (a2_side_effects_p)
419 result = build2 (COMPOUND_EXPR, result_type, a2, result);
424 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
425 type TYPE. We know that TYPE is a modular type with a nonbinary
429 nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
432 tree modulus = TYPE_MODULUS (type);
433 unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
434 unsigned int precision;
435 bool unsignedp = true;
439 /* If this is an addition of a constant, convert it to a subtraction
440 of a constant since we can do that faster. */
441 if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
443 rhs = fold_build2 (MINUS_EXPR, type, modulus, rhs);
444 op_code = MINUS_EXPR;
447 /* For the logical operations, we only need PRECISION bits. For
448 addition and subtraction, we need one more and for multiplication we
449 need twice as many. But we never want to make a size smaller than
451 if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
452 needed_precision += 1;
453 else if (op_code == MULT_EXPR)
454 needed_precision *= 2;
456 precision = MAX (needed_precision, TYPE_PRECISION (op_type));
458 /* Unsigned will do for everything but subtraction. */
459 if (op_code == MINUS_EXPR)
462 /* If our type is the wrong signedness or isn't wide enough, make a new
463 type and convert both our operands to it. */
464 if (TYPE_PRECISION (op_type) < precision
465 || TYPE_UNSIGNED (op_type) != unsignedp)
467 /* Copy the node so we ensure it can be modified to make it modular. */
468 op_type = copy_node (gnat_type_for_size (precision, unsignedp));
469 modulus = convert (op_type, modulus);
470 SET_TYPE_MODULUS (op_type, modulus);
471 TYPE_MODULAR_P (op_type) = 1;
472 lhs = convert (op_type, lhs);
473 rhs = convert (op_type, rhs);
476 /* Do the operation, then we'll fix it up. */
477 result = fold_build2 (op_code, op_type, lhs, rhs);
479 /* For multiplication, we have no choice but to do a full modulus
480 operation. However, we want to do this in the narrowest
482 if (op_code == MULT_EXPR)
484 tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
485 modulus = convert (div_type, modulus);
486 SET_TYPE_MODULUS (div_type, modulus);
487 TYPE_MODULAR_P (div_type) = 1;
488 result = convert (op_type,
489 fold_build2 (TRUNC_MOD_EXPR, div_type,
490 convert (div_type, result), modulus));
493 /* For subtraction, add the modulus back if we are negative. */
494 else if (op_code == MINUS_EXPR)
496 result = gnat_protect_expr (result);
497 result = fold_build3 (COND_EXPR, op_type,
498 fold_build2 (LT_EXPR, boolean_type_node, result,
499 convert (op_type, integer_zero_node)),
500 fold_build2 (PLUS_EXPR, op_type, result, modulus),
504 /* For the other operations, subtract the modulus if we are >= it. */
507 result = gnat_protect_expr (result);
508 result = fold_build3 (COND_EXPR, op_type,
509 fold_build2 (GE_EXPR, boolean_type_node,
511 fold_build2 (MINUS_EXPR, op_type,
516 return convert (type, result);
519 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
520 desired for the result. Usually the operation is to be performed
521 in that type. For INIT_EXPR and MODIFY_EXPR, RESULT_TYPE must be
522 NULL_TREE. For ARRAY_REF, RESULT_TYPE may be NULL_TREE, in which
523 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 && TREE_CODE (operation_type) == INTEGER_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 #ifdef ENABLE_CHECKING
562 gcc_assert (result_type == NULL_TREE);
564 /* If there were integral or pointer conversions on the LHS, remove
565 them; we'll be putting them back below if needed. Likewise for
566 conversions between array and record types, except for justified
567 modular types. But don't do this if the right operand is not
568 BLKmode (for packed arrays) unless we are not changing the mode. */
569 while ((CONVERT_EXPR_P (left_operand)
570 || TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
571 && (((INTEGRAL_TYPE_P (left_type)
572 || POINTER_TYPE_P (left_type))
573 && (INTEGRAL_TYPE_P (TREE_TYPE
574 (TREE_OPERAND (left_operand, 0)))
575 || POINTER_TYPE_P (TREE_TYPE
576 (TREE_OPERAND (left_operand, 0)))))
577 || (((TREE_CODE (left_type) == RECORD_TYPE
578 && !TYPE_JUSTIFIED_MODULAR_P (left_type))
579 || TREE_CODE (left_type) == ARRAY_TYPE)
580 && ((TREE_CODE (TREE_TYPE
581 (TREE_OPERAND (left_operand, 0)))
583 || (TREE_CODE (TREE_TYPE
584 (TREE_OPERAND (left_operand, 0)))
586 && (TYPE_MODE (right_type) == BLKmode
587 || (TYPE_MODE (left_type)
588 == TYPE_MODE (TREE_TYPE
590 (left_operand, 0))))))))
592 left_operand = TREE_OPERAND (left_operand, 0);
593 left_type = TREE_TYPE (left_operand);
596 /* If a class-wide type may be involved, force use of the RHS type. */
597 if ((TREE_CODE (right_type) == RECORD_TYPE
598 || TREE_CODE (right_type) == UNION_TYPE)
599 && TYPE_ALIGN_OK (right_type))
600 operation_type = right_type;
602 /* If we are copying between padded objects with compatible types, use
603 the padded view of the objects, this is very likely more efficient.
604 Likewise for a padded object that is assigned a constructor, if we
605 can convert the constructor to the inner type, to avoid putting a
606 VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
607 actually copied anything. */
608 else if (TYPE_IS_PADDING_P (left_type)
609 && TREE_CONSTANT (TYPE_SIZE (left_type))
610 && ((TREE_CODE (right_operand) == COMPONENT_REF
612 (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
613 && gnat_types_compatible_p
615 TREE_TYPE (TREE_OPERAND (right_operand, 0))))
616 || (TREE_CODE (right_operand) == CONSTRUCTOR
617 && !CONTAINS_PLACEHOLDER_P
618 (DECL_SIZE (TYPE_FIELDS (left_type)))))
619 && !integer_zerop (TYPE_SIZE (right_type)))
620 operation_type = left_type;
622 /* If we have a call to a function that returns an unconstrained type
623 with default discriminant on the RHS, use the RHS type (which is
624 padded) as we cannot compute the size of the actual assignment. */
625 else if (TREE_CODE (right_operand) == CALL_EXPR
626 && TYPE_IS_PADDING_P (right_type)
627 && CONTAINS_PLACEHOLDER_P
628 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (right_type)))))
629 operation_type = right_type;
631 /* Find the best type to use for copying between aggregate types. */
632 else if (((TREE_CODE (left_type) == ARRAY_TYPE
633 && TREE_CODE (right_type) == ARRAY_TYPE)
634 || (TREE_CODE (left_type) == RECORD_TYPE
635 && TREE_CODE (right_type) == RECORD_TYPE))
636 && (best_type = find_common_type (left_type, right_type)))
637 operation_type = best_type;
639 /* Otherwise use the LHS type. */
641 operation_type = left_type;
643 /* Ensure everything on the LHS is valid. If we have a field reference,
644 strip anything that get_inner_reference can handle. Then remove any
645 conversions between types having the same code and mode. And mark
646 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
647 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
648 result = left_operand;
651 tree restype = TREE_TYPE (result);
653 if (TREE_CODE (result) == COMPONENT_REF
654 || TREE_CODE (result) == ARRAY_REF
655 || TREE_CODE (result) == ARRAY_RANGE_REF)
656 while (handled_component_p (result))
657 result = TREE_OPERAND (result, 0);
658 else if (TREE_CODE (result) == REALPART_EXPR
659 || TREE_CODE (result) == IMAGPART_EXPR
660 || (CONVERT_EXPR_P (result)
661 && (((TREE_CODE (restype)
662 == TREE_CODE (TREE_TYPE
663 (TREE_OPERAND (result, 0))))
664 && (TYPE_MODE (TREE_TYPE
665 (TREE_OPERAND (result, 0)))
666 == TYPE_MODE (restype)))
667 || TYPE_ALIGN_OK (restype))))
668 result = TREE_OPERAND (result, 0);
669 else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
671 TREE_ADDRESSABLE (result) = 1;
672 result = TREE_OPERAND (result, 0);
678 gcc_assert (TREE_CODE (result) == INDIRECT_REF
679 || TREE_CODE (result) == NULL_EXPR
682 /* Convert the right operand to the operation type unless it is
683 either already of the correct type or if the type involves a
684 placeholder, since the RHS may not have the same record type. */
685 if (operation_type != right_type
686 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type)))
688 right_operand = convert (operation_type, right_operand);
689 right_type = operation_type;
692 /* If the left operand is not of the same type as the operation
693 type, wrap it up in a VIEW_CONVERT_EXPR. */
694 if (left_type != operation_type)
695 left_operand = unchecked_convert (operation_type, left_operand, false);
697 has_side_effects = true;
703 operation_type = TREE_TYPE (left_type);
705 /* ... fall through ... */
707 case ARRAY_RANGE_REF:
708 /* First look through conversion between type variants. Note that
709 this changes neither the operation type nor the type domain. */
710 if (TREE_CODE (left_operand) == VIEW_CONVERT_EXPR
711 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand, 0)))
712 == TYPE_MAIN_VARIANT (left_type))
714 left_operand = TREE_OPERAND (left_operand, 0);
715 left_type = TREE_TYPE (left_operand);
718 /* For a range, make sure the element type is consistent. */
719 if (op_code == ARRAY_RANGE_REF
720 && TREE_TYPE (operation_type) != TREE_TYPE (left_type))
721 operation_type = build_array_type (TREE_TYPE (left_type),
722 TYPE_DOMAIN (operation_type));
724 /* Then convert the right operand to its base type. This will prevent
725 unneeded sign conversions when sizetype is wider than integer. */
726 right_operand = convert (right_base_type, right_operand);
727 right_operand = convert (sizetype, right_operand);
731 case TRUTH_ANDIF_EXPR:
732 case TRUTH_ORIF_EXPR:
736 #ifdef ENABLE_CHECKING
737 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
739 operation_type = left_base_type;
740 left_operand = convert (operation_type, left_operand);
741 right_operand = convert (operation_type, right_operand);
750 #ifdef ENABLE_CHECKING
751 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
753 /* If either operand is a NULL_EXPR, just return a new one. */
754 if (TREE_CODE (left_operand) == NULL_EXPR)
755 return build2 (op_code, result_type,
756 build1 (NULL_EXPR, integer_type_node,
757 TREE_OPERAND (left_operand, 0)),
760 else if (TREE_CODE (right_operand) == NULL_EXPR)
761 return build2 (op_code, result_type,
762 build1 (NULL_EXPR, integer_type_node,
763 TREE_OPERAND (right_operand, 0)),
766 /* If either object is a justified modular types, get the
767 fields from within. */
768 if (TREE_CODE (left_type) == RECORD_TYPE
769 && TYPE_JUSTIFIED_MODULAR_P (left_type))
771 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
773 left_type = TREE_TYPE (left_operand);
774 left_base_type = get_base_type (left_type);
777 if (TREE_CODE (right_type) == RECORD_TYPE
778 && TYPE_JUSTIFIED_MODULAR_P (right_type))
780 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
782 right_type = TREE_TYPE (right_operand);
783 right_base_type = get_base_type (right_type);
786 /* If both objects are arrays, compare them specially. */
787 if ((TREE_CODE (left_type) == ARRAY_TYPE
788 || (TREE_CODE (left_type) == INTEGER_TYPE
789 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
790 && (TREE_CODE (right_type) == ARRAY_TYPE
791 || (TREE_CODE (right_type) == INTEGER_TYPE
792 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
794 result = compare_arrays (input_location,
795 result_type, left_operand, right_operand);
796 if (op_code == NE_EXPR)
797 result = invert_truthvalue_loc (EXPR_LOCATION (result), result);
799 gcc_assert (op_code == EQ_EXPR);
804 /* Otherwise, the base types must be the same, unless they are both fat
805 pointer types or record types. In the latter case, use the best type
806 and convert both operands to that type. */
807 if (left_base_type != right_base_type)
809 if (TYPE_IS_FAT_POINTER_P (left_base_type)
810 && TYPE_IS_FAT_POINTER_P (right_base_type))
812 gcc_assert (TYPE_MAIN_VARIANT (left_base_type)
813 == TYPE_MAIN_VARIANT (right_base_type));
814 best_type = left_base_type;
817 else if (TREE_CODE (left_base_type) == RECORD_TYPE
818 && TREE_CODE (right_base_type) == RECORD_TYPE)
820 /* The only way this is permitted is if both types have the same
821 name. In that case, one of them must not be self-referential.
822 Use it as the best type. Even better with a fixed size. */
823 gcc_assert (TYPE_NAME (left_base_type)
824 && TYPE_NAME (left_base_type)
825 == TYPE_NAME (right_base_type));
827 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
828 best_type = left_base_type;
829 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
830 best_type = right_base_type;
831 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
832 best_type = left_base_type;
833 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
834 best_type = right_base_type;
842 left_operand = convert (best_type, left_operand);
843 right_operand = convert (best_type, right_operand);
847 left_operand = convert (left_base_type, left_operand);
848 right_operand = convert (right_base_type, right_operand);
851 /* If we are comparing a fat pointer against zero, we just need to
852 compare the data pointer. */
853 if (TYPE_IS_FAT_POINTER_P (left_base_type)
854 && TREE_CODE (right_operand) == CONSTRUCTOR
855 && integer_zerop (VEC_index (constructor_elt,
856 CONSTRUCTOR_ELTS (right_operand),
860 = build_component_ref (left_operand, NULL_TREE,
861 TYPE_FIELDS (left_base_type), false);
863 = convert (TREE_TYPE (left_operand), integer_zero_node);
873 /* The RHS of a shift can be any type. Also, ignore any modulus
874 (we used to abort, but this is needed for unchecked conversion
875 to modular types). Otherwise, processing is the same as normal. */
876 gcc_assert (operation_type == left_base_type);
878 left_operand = convert (operation_type, left_operand);
884 /* For binary modulus, if the inputs are in range, so are the
886 if (modulus && integer_pow2p (modulus))
891 gcc_assert (TREE_TYPE (result_type) == left_base_type
892 && TREE_TYPE (result_type) == right_base_type);
893 left_operand = convert (left_base_type, left_operand);
894 right_operand = convert (right_base_type, right_operand);
897 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
898 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
899 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
900 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
901 /* These always produce results lower than either operand. */
905 case POINTER_PLUS_EXPR:
906 gcc_assert (operation_type == left_base_type
907 && sizetype == right_base_type);
908 left_operand = convert (operation_type, left_operand);
909 right_operand = convert (sizetype, right_operand);
912 case PLUS_NOMOD_EXPR:
913 case MINUS_NOMOD_EXPR:
914 if (op_code == PLUS_NOMOD_EXPR)
917 op_code = MINUS_EXPR;
920 /* ... fall through ... */
924 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
925 other compilers. Contrary to C, Ada doesn't allow arithmetics in
926 these types but can generate addition/subtraction for Succ/Pred. */
928 && (TREE_CODE (operation_type) == ENUMERAL_TYPE
929 || TREE_CODE (operation_type) == BOOLEAN_TYPE))
930 operation_type = left_base_type = right_base_type
931 = gnat_type_for_mode (TYPE_MODE (operation_type),
932 TYPE_UNSIGNED (operation_type));
934 /* ... fall through ... */
938 /* The result type should be the same as the base types of the
939 both operands (and they should be the same). Convert
940 everything to the result type. */
942 gcc_assert (operation_type == left_base_type
943 && left_base_type == right_base_type);
944 left_operand = convert (operation_type, left_operand);
945 right_operand = convert (operation_type, right_operand);
948 if (modulus && !integer_pow2p (modulus))
950 result = nonbinary_modular_operation (op_code, operation_type,
951 left_operand, right_operand);
954 /* If either operand is a NULL_EXPR, just return a new one. */
955 else if (TREE_CODE (left_operand) == NULL_EXPR)
956 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
957 else if (TREE_CODE (right_operand) == NULL_EXPR)
958 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
959 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
960 result = fold (build4 (op_code, operation_type, left_operand,
961 right_operand, NULL_TREE, NULL_TREE));
962 else if (op_code == INIT_EXPR || op_code == MODIFY_EXPR)
963 result = build2 (op_code, void_type_node, left_operand, right_operand);
966 = fold_build2 (op_code, operation_type, left_operand, right_operand);
968 if (TREE_CONSTANT (result))
970 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
972 TREE_THIS_NOTRAP (result) = 1;
973 if (TYPE_VOLATILE (operation_type))
974 TREE_THIS_VOLATILE (result) = 1;
977 TREE_CONSTANT (result)
978 |= (TREE_CONSTANT (left_operand) && TREE_CONSTANT (right_operand));
980 TREE_SIDE_EFFECTS (result) |= has_side_effects;
982 /* If we are working with modular types, perform the MOD operation
983 if something above hasn't eliminated the need for it. */
985 result = fold_build2 (FLOOR_MOD_EXPR, operation_type, result,
986 convert (operation_type, modulus));
988 if (result_type && result_type != operation_type)
989 result = convert (result_type, result);
994 /* Similar, but for unary operations. */
997 build_unary_op (enum tree_code op_code, tree result_type, tree operand)
999 tree type = TREE_TYPE (operand);
1000 tree base_type = get_base_type (type);
1001 tree operation_type = result_type;
1003 bool side_effects = false;
1006 && TREE_CODE (operation_type) == RECORD_TYPE
1007 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
1008 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
1011 && TREE_CODE (operation_type) == INTEGER_TYPE
1012 && TYPE_EXTRA_SUBTYPE_P (operation_type))
1013 operation_type = get_base_type (operation_type);
1019 if (!operation_type)
1020 result_type = operation_type = TREE_TYPE (type);
1022 gcc_assert (result_type == TREE_TYPE (type));
1024 result = fold_build1 (op_code, operation_type, operand);
1027 case TRUTH_NOT_EXPR:
1028 #ifdef ENABLE_CHECKING
1029 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
1031 result = invert_truthvalue_loc (EXPR_LOCATION (operand), operand);
1032 /* When not optimizing, fold the result as invert_truthvalue_loc
1033 doesn't fold the result of comparisons. This is intended to undo
1034 the trick used for boolean rvalues in gnat_to_gnu. */
1036 result = fold (result);
1039 case ATTR_ADDR_EXPR:
1041 switch (TREE_CODE (operand))
1044 case UNCONSTRAINED_ARRAY_REF:
1045 result = TREE_OPERAND (operand, 0);
1047 /* Make sure the type here is a pointer, not a reference.
1048 GCC wants pointer types for function addresses. */
1050 result_type = build_pointer_type (type);
1052 /* If the underlying object can alias everything, propagate the
1053 property since we are effectively retrieving the object. */
1054 if (POINTER_TYPE_P (TREE_TYPE (result))
1055 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1057 if (TREE_CODE (result_type) == POINTER_TYPE
1058 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1060 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1061 TYPE_MODE (result_type),
1063 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1064 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1066 = build_reference_type_for_mode (TREE_TYPE (result_type),
1067 TYPE_MODE (result_type),
1074 TREE_TYPE (result) = type = build_pointer_type (type);
1078 /* Fold a compound expression if it has unconstrained array type
1079 since the middle-end cannot handle it. But we don't it in the
1080 general case because it may introduce aliasing issues if the
1081 first operand is an indirect assignment and the second operand
1082 the corresponding address, e.g. for an allocator. */
1083 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
1085 result = build_unary_op (ADDR_EXPR, result_type,
1086 TREE_OPERAND (operand, 1));
1087 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1088 TREE_OPERAND (operand, 0), result);
1094 case ARRAY_RANGE_REF:
1097 /* If this is for 'Address, find the address of the prefix and add
1098 the offset to the field. Otherwise, do this the normal way. */
1099 if (op_code == ATTR_ADDR_EXPR)
1101 HOST_WIDE_INT bitsize;
1102 HOST_WIDE_INT bitpos;
1104 enum machine_mode mode;
1105 int unsignedp, volatilep;
1107 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1108 &mode, &unsignedp, &volatilep,
1111 /* If INNER is a padding type whose field has a self-referential
1112 size, convert to that inner type. We know the offset is zero
1113 and we need to have that type visible. */
1114 if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
1115 && CONTAINS_PLACEHOLDER_P
1116 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1117 (TREE_TYPE (inner))))))
1118 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1121 /* Compute the offset as a byte offset from INNER. */
1123 offset = size_zero_node;
1125 offset = size_binop (PLUS_EXPR, offset,
1126 size_int (bitpos / BITS_PER_UNIT));
1128 /* Take the address of INNER, convert the offset to void *, and
1129 add then. It will later be converted to the desired result
1131 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1132 inner = convert (ptr_void_type_node, inner);
1133 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1135 result = convert (build_pointer_type (TREE_TYPE (operand)),
1142 /* If this is just a constructor for a padded record, we can
1143 just take the address of the single field and convert it to
1144 a pointer to our type. */
1145 if (TYPE_IS_PADDING_P (type))
1147 result = VEC_index (constructor_elt,
1148 CONSTRUCTOR_ELTS (operand),
1150 result = convert (build_pointer_type (TREE_TYPE (operand)),
1151 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1158 if (AGGREGATE_TYPE_P (type)
1159 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1160 return build_unary_op (ADDR_EXPR, result_type,
1161 TREE_OPERAND (operand, 0));
1163 /* ... fallthru ... */
1165 case VIEW_CONVERT_EXPR:
1166 /* If this just a variant conversion or if the conversion doesn't
1167 change the mode, get the result type from this type and go down.
1168 This is needed for conversions of CONST_DECLs, to eventually get
1169 to the address of their CORRESPONDING_VARs. */
1170 if ((TYPE_MAIN_VARIANT (type)
1171 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1172 || (TYPE_MODE (type) != BLKmode
1173 && (TYPE_MODE (type)
1174 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1175 return build_unary_op (ADDR_EXPR,
1176 (result_type ? result_type
1177 : build_pointer_type (type)),
1178 TREE_OPERAND (operand, 0));
1182 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1184 /* ... fall through ... */
1189 /* If we are taking the address of a padded record whose field is
1190 contains a template, take the address of the template. */
1191 if (TYPE_IS_PADDING_P (type)
1192 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1193 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1195 type = TREE_TYPE (TYPE_FIELDS (type));
1196 operand = convert (type, operand);
1199 gnat_mark_addressable (operand);
1200 result = build_fold_addr_expr (operand);
1203 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1207 /* If we want to refer to an unconstrained array, use the appropriate
1208 expression to do so. This will never survive down to the back-end.
1209 But if TYPE is a thin pointer, first convert to a fat pointer. */
1210 if (TYPE_IS_THIN_POINTER_P (type)
1211 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1214 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1216 type = TREE_TYPE (operand);
1219 if (TYPE_IS_FAT_POINTER_P (type))
1221 result = build1 (UNCONSTRAINED_ARRAY_REF,
1222 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1223 TREE_READONLY (result)
1224 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1227 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1228 else if (TREE_CODE (operand) == ADDR_EXPR)
1229 result = TREE_OPERAND (operand, 0);
1231 /* Otherwise, build and fold the indirect reference. */
1234 result = build_fold_indirect_ref (operand);
1235 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1239 = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1245 tree modulus = ((operation_type
1246 && TREE_CODE (operation_type) == INTEGER_TYPE
1247 && TYPE_MODULAR_P (operation_type))
1248 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1249 int mod_pow2 = modulus && integer_pow2p (modulus);
1251 /* If this is a modular type, there are various possibilities
1252 depending on the operation and whether the modulus is a
1253 power of two or not. */
1257 gcc_assert (operation_type == base_type);
1258 operand = convert (operation_type, operand);
1260 /* The fastest in the negate case for binary modulus is
1261 the straightforward code; the TRUNC_MOD_EXPR below
1262 is an AND operation. */
1263 if (op_code == NEGATE_EXPR && mod_pow2)
1264 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1265 fold_build1 (NEGATE_EXPR, operation_type,
1269 /* For nonbinary negate case, return zero for zero operand,
1270 else return the modulus minus the operand. If the modulus
1271 is a power of two minus one, we can do the subtraction
1272 as an XOR since it is equivalent and faster on most machines. */
1273 else if (op_code == NEGATE_EXPR && !mod_pow2)
1275 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1277 convert (operation_type,
1278 integer_one_node))))
1279 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1282 result = fold_build2 (MINUS_EXPR, operation_type,
1285 result = fold_build3 (COND_EXPR, operation_type,
1286 fold_build2 (NE_EXPR,
1291 integer_zero_node)),
1296 /* For the NOT cases, we need a constant equal to
1297 the modulus minus one. For a binary modulus, we
1298 XOR against the constant and subtract the operand from
1299 that constant for nonbinary modulus. */
1301 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1302 convert (operation_type,
1306 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1309 result = fold_build2 (MINUS_EXPR, operation_type,
1317 /* ... fall through ... */
1320 gcc_assert (operation_type == base_type);
1321 result = fold_build1 (op_code, operation_type,
1322 convert (operation_type, operand));
1327 TREE_SIDE_EFFECTS (result) = 1;
1328 if (TREE_CODE (result) == INDIRECT_REF)
1329 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1332 if (result_type && TREE_TYPE (result) != result_type)
1333 result = convert (result_type, result);
1338 /* Similar, but for COND_EXPR. */
1341 build_cond_expr (tree result_type, tree condition_operand,
1342 tree true_operand, tree false_operand)
1344 bool addr_p = false;
1347 /* The front-end verified that result, true and false operands have
1348 same base type. Convert everything to the result type. */
1349 true_operand = convert (result_type, true_operand);
1350 false_operand = convert (result_type, false_operand);
1352 /* If the result type is unconstrained, take the address of the operands and
1353 then dereference the result. Likewise if the result type is passed by
1354 reference, but this is natively handled in the gimplifier. */
1355 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1356 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1358 result_type = build_pointer_type (result_type);
1359 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1360 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1364 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1365 true_operand, false_operand);
1367 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1368 in both arms, make sure it gets evaluated by moving it ahead of the
1369 conditional expression. This is necessary because it is evaluated
1370 in only one place at run time and would otherwise be uninitialized
1371 in one of the arms. */
1372 true_operand = skip_simple_arithmetic (true_operand);
1373 false_operand = skip_simple_arithmetic (false_operand);
1375 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1376 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1379 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1384 /* Similar, but for COMPOUND_EXPR. */
1387 build_compound_expr (tree result_type, tree stmt_operand, tree expr_operand)
1389 bool addr_p = false;
1392 /* If the result type is unconstrained, take the address of the operand and
1393 then dereference the result. Likewise if the result type is passed by
1394 reference, but this is natively handled in the gimplifier. */
1395 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1396 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1398 result_type = build_pointer_type (result_type);
1399 expr_operand = build_unary_op (ADDR_EXPR, result_type, expr_operand);
1403 result = fold_build2 (COMPOUND_EXPR, result_type, stmt_operand,
1407 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1412 /* Conveniently construct a function call expression. FNDECL names the
1413 function to be called, N is the number of arguments, and the "..."
1414 parameters are the argument expressions. Unlike build_call_expr
1415 this doesn't fold the call, hence it will always return a CALL_EXPR. */
1418 build_call_n_expr (tree fndecl, int n, ...)
1421 tree fntype = TREE_TYPE (fndecl);
1422 tree fn = build1 (ADDR_EXPR, build_pointer_type (fntype), fndecl);
1425 fn = build_call_valist (TREE_TYPE (fntype), fn, n, ap);
1430 /* Call a function that raises an exception and pass the line number and file
1431 name, if requested. MSG says which exception function to call.
1433 GNAT_NODE is the gnat node conveying the source location for which the
1434 error should be signaled, or Empty in which case the error is signaled on
1435 the current ref_file_name/input_line.
1437 KIND says which kind of exception this is for
1438 (N_Raise_{Constraint,Storage,Program}_Error). */
1441 build_call_raise (int msg, Node_Id gnat_node, char kind)
1443 tree fndecl = gnat_raise_decls[msg];
1444 tree label = get_exception_label (kind);
1450 /* If this is to be done as a goto, handle that case. */
1453 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1454 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1456 /* If Local_Raise is present, generate
1457 Local_Raise (exception'Identity); */
1458 if (Present (local_raise))
1460 tree gnu_local_raise
1461 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1462 tree gnu_exception_entity
1463 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1465 = build_call_n_expr (gnu_local_raise, 1,
1466 build_unary_op (ADDR_EXPR, NULL_TREE,
1467 gnu_exception_entity));
1469 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1470 gnu_call, gnu_result);}
1476 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1478 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1479 ? IDENTIFIER_POINTER
1480 (get_identifier (Get_Name_String
1482 (Get_Source_File_Index (Sloc (gnat_node))))))
1486 filename = build_string (len, str);
1488 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1489 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1491 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1492 build_index_type (size_int (len)));
1495 build_call_n_expr (fndecl, 2,
1497 build_pointer_type (unsigned_char_type_node),
1499 build_int_cst (NULL_TREE, line_number));
1502 /* Similar to build_call_raise, for an index or range check exception as
1503 determined by MSG, with extra information generated of the form
1504 "INDEX out of range FIRST..LAST". */
1507 build_call_raise_range (int msg, Node_Id gnat_node,
1508 tree index, tree first, tree last)
1510 tree fndecl = gnat_raise_decls_ext[msg];
1512 int line_number, column_number;
1517 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1519 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1520 ? IDENTIFIER_POINTER
1521 (get_identifier (Get_Name_String
1523 (Get_Source_File_Index (Sloc (gnat_node))))))
1527 filename = build_string (len, str);
1528 if (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1530 line_number = Get_Logical_Line_Number (Sloc (gnat_node));
1531 column_number = Get_Column_Number (Sloc (gnat_node));
1535 line_number = input_line;
1539 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1540 build_index_type (size_int (len)));
1543 build_call_n_expr (fndecl, 6,
1545 build_pointer_type (unsigned_char_type_node),
1547 build_int_cst (NULL_TREE, line_number),
1548 build_int_cst (NULL_TREE, column_number),
1549 convert (integer_type_node, index),
1550 convert (integer_type_node, first),
1551 convert (integer_type_node, last));
1554 /* Similar to build_call_raise, with extra information about the column
1555 where the check failed. */
1558 build_call_raise_column (int msg, Node_Id gnat_node)
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)));
1593 build_call_n_expr (fndecl, 3,
1595 build_pointer_type (unsigned_char_type_node),
1597 build_int_cst (NULL_TREE, line_number),
1598 build_int_cst (NULL_TREE, column_number));
1601 /* qsort comparer for the bit positions of two constructor elements
1602 for record components. */
1605 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1607 const constructor_elt * const elmt1 = (const constructor_elt * const) rt1;
1608 const constructor_elt * const elmt2 = (const constructor_elt * const) rt2;
1609 const_tree const field1 = elmt1->index;
1610 const_tree const field2 = elmt2->index;
1612 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1614 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1617 /* Return a CONSTRUCTOR of TYPE whose elements are V. */
1620 gnat_build_constructor (tree type, VEC(constructor_elt,gc) *v)
1622 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1623 bool side_effects = false;
1624 tree result, obj, val;
1625 unsigned int n_elmts;
1627 /* Scan the elements to see if they are all constant or if any has side
1628 effects, to let us set global flags on the resulting constructor. Count
1629 the elements along the way for possible sorting purposes below. */
1630 FOR_EACH_CONSTRUCTOR_ELT (v, n_elmts, obj, val)
1632 /* The predicate must be in keeping with output_constructor. */
1633 if (!TREE_CONSTANT (val)
1634 || (TREE_CODE (type) == RECORD_TYPE
1635 && CONSTRUCTOR_BITFIELD_P (obj)
1636 && !initializer_constant_valid_for_bitfield_p (val))
1637 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1638 allconstant = false;
1640 if (TREE_SIDE_EFFECTS (val))
1641 side_effects = true;
1644 /* For record types with constant components only, sort field list
1645 by increasing bit position. This is necessary to ensure the
1646 constructor can be output as static data. */
1647 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1648 VEC_qsort (constructor_elt, v, compare_elmt_bitpos);
1650 result = build_constructor (type, v);
1651 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1652 TREE_SIDE_EFFECTS (result) = side_effects;
1653 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1657 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1658 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1659 for the field. Don't fold the result if NO_FOLD_P is true.
1661 We also handle the fact that we might have been passed a pointer to the
1662 actual record and know how to look for fields in variant parts. */
1665 build_simple_component_ref (tree record_variable, tree component,
1666 tree field, bool no_fold_p)
1668 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1669 tree ref, inner_variable;
1671 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1672 || TREE_CODE (record_type) == UNION_TYPE
1673 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1674 && TYPE_SIZE (record_type)
1675 && (component != 0) != (field != 0));
1677 /* If no field was specified, look for a field with the specified name
1678 in the current record only. */
1680 for (field = TYPE_FIELDS (record_type); field;
1681 field = TREE_CHAIN (field))
1682 if (DECL_NAME (field) == component)
1688 /* If this field is not in the specified record, see if we can find a field
1689 in the specified record whose original field is the same as this one. */
1690 if (DECL_CONTEXT (field) != record_type)
1694 /* First loop thru normal components. */
1695 for (new_field = TYPE_FIELDS (record_type); new_field;
1696 new_field = DECL_CHAIN (new_field))
1697 if (SAME_FIELD_P (field, new_field))
1700 /* Next, see if we're looking for an inherited component in an extension.
1701 If so, look thru the extension directly. */
1703 && TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1704 && TYPE_ALIGN_OK (record_type)
1705 && TREE_CODE (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1707 && TYPE_ALIGN_OK (TREE_TYPE (TREE_OPERAND (record_variable, 0))))
1709 ref = build_simple_component_ref (TREE_OPERAND (record_variable, 0),
1710 NULL_TREE, field, no_fold_p);
1715 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1716 the component in the first search. Doing this search in 2 steps
1717 is required to avoiding hidden homonymous fields in the
1720 for (new_field = TYPE_FIELDS (record_type); new_field;
1721 new_field = DECL_CHAIN (new_field))
1722 if (DECL_INTERNAL_P (new_field))
1725 = build_simple_component_ref (record_variable,
1726 NULL_TREE, new_field, no_fold_p);
1727 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1740 /* If the field's offset has overflowed, do not attempt to access it
1741 as doing so may trigger sanity checks deeper in the back-end.
1742 Note that we don't need to warn since this will be done on trying
1743 to declare the object. */
1744 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1745 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1748 /* Look through conversion between type variants. Note that this
1749 is transparent as far as the field is concerned. */
1750 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1751 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1753 inner_variable = TREE_OPERAND (record_variable, 0);
1755 inner_variable = record_variable;
1757 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1760 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1761 TREE_READONLY (ref) = 1;
1762 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1763 || TYPE_VOLATILE (record_type))
1764 TREE_THIS_VOLATILE (ref) = 1;
1769 /* The generic folder may punt in this case because the inner array type
1770 can be self-referential, but folding is in fact not problematic. */
1771 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1772 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1774 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1775 unsigned HOST_WIDE_INT idx;
1777 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1787 /* Like build_simple_component_ref, except that we give an error if the
1788 reference could not be found. */
1791 build_component_ref (tree record_variable, tree component,
1792 tree field, bool no_fold_p)
1794 tree ref = build_simple_component_ref (record_variable, component, field,
1800 /* If FIELD was specified, assume this is an invalid user field so raise
1801 Constraint_Error. Otherwise, we have no type to return so abort. */
1803 return build1 (NULL_EXPR, TREE_TYPE (field),
1804 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1805 N_Raise_Constraint_Error));
1808 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1809 identically. Process the case where a GNAT_PROC to call is provided. */
1812 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1813 Entity_Id gnat_proc, Entity_Id gnat_pool)
1815 tree gnu_proc = gnat_to_gnu (gnat_proc);
1818 /* The storage pools are obviously always tagged types, but the
1819 secondary stack uses the same mechanism and is not tagged. */
1820 if (Is_Tagged_Type (Etype (gnat_pool)))
1822 /* The size is the third parameter; the alignment is the
1824 Entity_Id gnat_size_type
1825 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1826 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1828 tree gnu_pool = gnat_to_gnu (gnat_pool);
1829 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1830 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1832 gnu_size = convert (gnu_size_type, gnu_size);
1833 gnu_align = convert (gnu_size_type, gnu_align);
1835 /* The first arg is always the address of the storage pool; next
1836 comes the address of the object, for a deallocator, then the
1837 size and alignment. */
1839 gnu_call = build_call_n_expr (gnu_proc, 4, gnu_pool_addr, gnu_obj,
1840 gnu_size, gnu_align);
1842 gnu_call = build_call_n_expr (gnu_proc, 3, gnu_pool_addr,
1843 gnu_size, gnu_align);
1846 /* Secondary stack case. */
1849 /* The size is the second parameter. */
1850 Entity_Id gnat_size_type
1851 = Etype (Next_Formal (First_Formal (gnat_proc)));
1852 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1854 gnu_size = convert (gnu_size_type, gnu_size);
1856 /* The first arg is the address of the object, for a deallocator,
1859 gnu_call = build_call_n_expr (gnu_proc, 2, gnu_obj, gnu_size);
1861 gnu_call = build_call_n_expr (gnu_proc, 1, gnu_size);
1867 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1868 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1869 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1873 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1875 /* When the DATA_TYPE alignment is stricter than what malloc offers
1876 (super-aligned case), we allocate an "aligning" wrapper type and return
1877 the address of its single data field with the malloc's return value
1878 stored just in front. */
1880 unsigned int data_align = TYPE_ALIGN (data_type);
1881 unsigned int system_allocator_alignment
1882 = get_target_system_allocator_alignment () * BITS_PER_UNIT;
1885 = ((data_align > system_allocator_alignment)
1886 ? make_aligning_type (data_type, data_align, data_size,
1887 system_allocator_alignment,
1888 POINTER_SIZE / BITS_PER_UNIT)
1892 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1896 /* On VMS, if pointers are 64-bit and the allocator size is 32-bit or
1897 Convention C, allocate 32-bit memory. */
1898 if (TARGET_ABI_OPEN_VMS
1899 && POINTER_SIZE == 64
1900 && Nkind (gnat_node) == N_Allocator
1901 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1902 || Convention (Etype (gnat_node)) == Convention_C))
1903 malloc_ptr = build_call_n_expr (malloc32_decl, 1, size_to_malloc);
1905 malloc_ptr = build_call_n_expr (malloc_decl, 1, size_to_malloc);
1909 /* Latch malloc's return value and get a pointer to the aligning field
1911 tree storage_ptr = gnat_protect_expr (malloc_ptr);
1913 tree aligning_record_addr
1914 = convert (build_pointer_type (aligning_type), storage_ptr);
1916 tree aligning_record
1917 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1920 = build_component_ref (aligning_record, NULL_TREE,
1921 TYPE_FIELDS (aligning_type), false);
1923 tree aligning_field_addr
1924 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1926 /* Then arrange to store the allocator's return value ahead
1928 tree storage_ptr_slot_addr
1929 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1930 convert (ptr_void_type_node, aligning_field_addr),
1931 size_int (-(HOST_WIDE_INT) POINTER_SIZE
1934 tree storage_ptr_slot
1935 = build_unary_op (INDIRECT_REF, NULL_TREE,
1936 convert (build_pointer_type (ptr_void_type_node),
1937 storage_ptr_slot_addr));
1940 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
1941 build_binary_op (MODIFY_EXPR, NULL_TREE,
1942 storage_ptr_slot, storage_ptr),
1943 aligning_field_addr);
1949 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
1950 designated by DATA_PTR using the __gnat_free entry point. */
1953 maybe_wrap_free (tree data_ptr, tree data_type)
1955 /* In the regular alignment case, we pass the data pointer straight to free.
1956 In the superaligned case, we need to retrieve the initial allocator
1957 return value, stored in front of the data block at allocation time. */
1959 unsigned int data_align = TYPE_ALIGN (data_type);
1960 unsigned int system_allocator_alignment
1961 = get_target_system_allocator_alignment () * BITS_PER_UNIT;
1965 if (data_align > system_allocator_alignment)
1967 /* DATA_FRONT_PTR (void *)
1968 = (void *)DATA_PTR - (void *)sizeof (void *)) */
1971 (POINTER_PLUS_EXPR, ptr_void_type_node,
1972 convert (ptr_void_type_node, data_ptr),
1973 size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
1975 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
1978 (INDIRECT_REF, NULL_TREE,
1979 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
1982 free_ptr = data_ptr;
1984 return build_call_n_expr (free_decl, 1, free_ptr);
1987 /* Build a GCC tree to call an allocation or deallocation function.
1988 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
1989 generate an allocator.
1991 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
1992 object type, used to determine the to-be-honored address alignment.
1993 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
1994 pool to use. If not present, malloc and free are used. GNAT_NODE is used
1995 to provide an error location for restriction violation messages. */
1998 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
1999 Entity_Id gnat_proc, Entity_Id gnat_pool,
2002 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
2004 /* Explicit proc to call ? This one is assumed to deal with the type
2005 alignment constraints. */
2006 if (Present (gnat_proc))
2007 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
2008 gnat_proc, gnat_pool);
2010 /* Otherwise, object to "free" or "malloc" with possible special processing
2011 for alignments stricter than what the default allocator honors. */
2013 return maybe_wrap_free (gnu_obj, gnu_type);
2016 /* Assert that we no longer can be called with this special pool. */
2017 gcc_assert (gnat_pool != -1);
2019 /* Check that we aren't violating the associated restriction. */
2020 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
2021 Check_No_Implicit_Heap_Alloc (gnat_node);
2023 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
2027 /* Build a GCC tree to correspond to allocating an object of TYPE whose
2028 initial value is INIT, if INIT is nonzero. Convert the expression to
2029 RESULT_TYPE, which must be some type of pointer. Return the tree.
2031 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
2032 the storage pool to use. GNAT_NODE is used to provide an error
2033 location for restriction violation messages. If IGNORE_INIT_TYPE is
2034 true, ignore the type of INIT for the purpose of determining the size;
2035 this will cause the maximum size to be allocated if TYPE is of
2036 self-referential size. */
2039 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
2040 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
2042 tree size = TYPE_SIZE_UNIT (type);
2045 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
2046 if (init && TREE_CODE (init) == NULL_EXPR)
2047 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
2049 /* If the initializer, if present, is a COND_EXPR, deal with each branch. */
2050 else if (init && TREE_CODE (init) == COND_EXPR)
2051 return build3 (COND_EXPR, result_type, TREE_OPERAND (init, 0),
2052 build_allocator (type, TREE_OPERAND (init, 1), result_type,
2053 gnat_proc, gnat_pool, gnat_node,
2055 build_allocator (type, TREE_OPERAND (init, 2), result_type,
2056 gnat_proc, gnat_pool, gnat_node,
2059 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
2060 sizes of the object and its template. Allocate the whole thing and
2061 fill in the parts that are known. */
2062 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
2065 = build_unc_object_type_from_ptr (result_type, type,
2066 get_identifier ("ALLOC"), false);
2067 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
2068 tree storage_ptr_type = build_pointer_type (storage_type);
2071 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2074 /* If the size overflows, pass -1 so the allocator will raise
2076 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2077 size = ssize_int (-1);
2079 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2080 gnat_proc, gnat_pool, gnat_node);
2081 storage = convert (storage_ptr_type, gnat_protect_expr (storage));
2083 /* If there is an initializing expression, then make a constructor for
2084 the entire object including the bounds and copy it into the object.
2085 If there is no initializing expression, just set the bounds. */
2088 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, 2);
2090 CONSTRUCTOR_APPEND_ELT (v, TYPE_FIELDS (storage_type),
2091 build_template (template_type, type, init));
2092 CONSTRUCTOR_APPEND_ELT (v, DECL_CHAIN (TYPE_FIELDS (storage_type)),
2096 build2 (COMPOUND_EXPR, storage_ptr_type,
2098 (MODIFY_EXPR, NULL_TREE,
2099 build_unary_op (INDIRECT_REF, NULL_TREE,
2100 convert (storage_ptr_type, storage)),
2101 gnat_build_constructor (storage_type, v)),
2102 convert (storage_ptr_type, storage)));
2106 (COMPOUND_EXPR, result_type,
2108 (MODIFY_EXPR, NULL_TREE,
2110 (build_unary_op (INDIRECT_REF, NULL_TREE,
2111 convert (storage_ptr_type, storage)),
2112 NULL_TREE, TYPE_FIELDS (storage_type), false),
2113 build_template (template_type, type, NULL_TREE)),
2114 convert (result_type, convert (storage_ptr_type, storage)));
2117 /* If we have an initializing expression, see if its size is simpler
2118 than the size from the type. */
2119 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2120 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2121 || CONTAINS_PLACEHOLDER_P (size)))
2122 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2124 /* If the size is still self-referential, reference the initializing
2125 expression, if it is present. If not, this must have been a
2126 call to allocate a library-level object, in which case we use
2127 the maximum size. */
2128 if (CONTAINS_PLACEHOLDER_P (size))
2130 if (!ignore_init_type && init)
2131 size = substitute_placeholder_in_expr (size, init);
2133 size = max_size (size, true);
2136 /* If the size overflows, pass -1 so the allocator will raise
2138 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2139 size = ssize_int (-1);
2141 result = convert (result_type,
2142 build_call_alloc_dealloc (NULL_TREE, size, type,
2143 gnat_proc, gnat_pool,
2146 /* If we have an initial value, protect the new address, assign the value
2147 and return the address with a COMPOUND_EXPR. */
2150 result = gnat_protect_expr (result);
2152 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2154 (MODIFY_EXPR, NULL_TREE,
2155 build_unary_op (INDIRECT_REF,
2156 TREE_TYPE (TREE_TYPE (result)), result),
2161 return convert (result_type, result);
2164 /* Indicate that we need to take the address of T and that it therefore
2165 should not be allocated in a register. Returns true if successful. */
2168 gnat_mark_addressable (tree t)
2171 switch (TREE_CODE (t))
2176 case ARRAY_RANGE_REF:
2179 case VIEW_CONVERT_EXPR:
2180 case NON_LVALUE_EXPR:
2182 t = TREE_OPERAND (t, 0);
2186 t = TREE_OPERAND (t, 1);
2190 TREE_ADDRESSABLE (t) = 1;
2196 TREE_ADDRESSABLE (t) = 1;
2200 TREE_ADDRESSABLE (t) = 1;
2204 return DECL_CONST_CORRESPONDING_VAR (t)
2205 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
2212 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2213 but we know how to handle our own nodes. */
2216 gnat_save_expr (tree exp)
2218 tree type = TREE_TYPE (exp);
2219 enum tree_code code = TREE_CODE (exp);
2221 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2224 if (code == UNCONSTRAINED_ARRAY_REF)
2226 tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
2227 TREE_READONLY (t) = TYPE_READONLY (type);
2231 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2232 This may be more efficient, but will also allow us to more easily find
2233 the match for the PLACEHOLDER_EXPR. */
2234 if (code == COMPONENT_REF
2235 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2236 return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
2237 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2239 return save_expr (exp);
2242 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2243 is optimized under the assumption that EXP's value doesn't change before
2244 its subsequent reuse(s) except through its potential reevaluation. */
2247 gnat_protect_expr (tree exp)
2249 tree type = TREE_TYPE (exp);
2250 enum tree_code code = TREE_CODE (exp);
2252 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2255 /* If EXP has no side effects, we theoretically don't need to do anything.
2256 However, we may be recursively passed more and more complex expressions
2257 involving checks which will be reused multiple times and eventually be
2258 unshared for gimplification; in order to avoid a complexity explosion
2259 at that point, we protect any expressions more complex than a simple
2260 arithmetic expression. */
2261 if (!TREE_SIDE_EFFECTS (exp))
2263 tree inner = skip_simple_arithmetic (exp);
2264 if (!EXPR_P (inner) || REFERENCE_CLASS_P (inner))
2268 /* If this is a conversion, protect what's inside the conversion. */
2269 if (code == NON_LVALUE_EXPR
2270 || CONVERT_EXPR_CODE_P (code)
2271 || code == VIEW_CONVERT_EXPR)
2272 return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2274 /* If we're indirectly referencing something, we only need to protect the
2275 address since the data itself can't change in these situations. */
2276 if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
2278 tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2279 TREE_READONLY (t) = TYPE_READONLY (type);
2283 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2284 This may be more efficient, but will also allow us to more easily find
2285 the match for the PLACEHOLDER_EXPR. */
2286 if (code == COMPONENT_REF
2287 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2288 return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
2289 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2291 /* If this is a fat pointer or something that can be placed in a register,
2292 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2293 returned via invisible reference in most ABIs so the temporary will
2294 directly be filled by the callee. */
2295 if (TYPE_IS_FAT_POINTER_P (type)
2296 || TYPE_MODE (type) != BLKmode
2297 || code == CALL_EXPR)
2298 return save_expr (exp);
2300 /* Otherwise reference, protect the address and dereference. */
2302 build_unary_op (INDIRECT_REF, type,
2303 save_expr (build_unary_op (ADDR_EXPR,
2304 build_reference_type (type),
2308 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2309 argument to force evaluation of everything. */
2312 gnat_stabilize_reference_1 (tree e, bool force)
2314 enum tree_code code = TREE_CODE (e);
2315 tree type = TREE_TYPE (e);
2318 /* We cannot ignore const expressions because it might be a reference
2319 to a const array but whose index contains side-effects. But we can
2320 ignore things that are actual constant or that already have been
2321 handled by this function. */
2322 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2325 switch (TREE_CODE_CLASS (code))
2327 case tcc_exceptional:
2328 case tcc_declaration:
2329 case tcc_comparison:
2330 case tcc_expression:
2333 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2334 fat pointer. This may be more efficient, but will also allow
2335 us to more easily find the match for the PLACEHOLDER_EXPR. */
2336 if (code == COMPONENT_REF
2337 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
2339 = build3 (code, type,
2340 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2341 TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
2342 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2343 so that it will only be evaluated once. */
2344 /* The tcc_reference and tcc_comparison classes could be handled as
2345 below, but it is generally faster to only evaluate them once. */
2346 else if (TREE_SIDE_EFFECTS (e) || force)
2347 return save_expr (e);
2353 /* Recursively stabilize each operand. */
2355 = build2 (code, type,
2356 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2357 gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
2361 /* Recursively stabilize each operand. */
2363 = build1 (code, type,
2364 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
2371 /* See similar handling in gnat_stabilize_reference. */
2372 TREE_READONLY (result) = TREE_READONLY (e);
2373 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
2374 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2376 if (code == INDIRECT_REF || code == ARRAY_REF || code == ARRAY_RANGE_REF)
2377 TREE_THIS_NOTRAP (result) = TREE_THIS_NOTRAP (e);
2382 /* This is equivalent to stabilize_reference in tree.c but we know how to
2383 handle our own nodes and we take extra arguments. FORCE says whether to
2384 force evaluation of everything. We set SUCCESS to true unless we walk
2385 through something we don't know how to stabilize. */
2388 gnat_stabilize_reference (tree ref, bool force, bool *success)
2390 tree type = TREE_TYPE (ref);
2391 enum tree_code code = TREE_CODE (ref);
2394 /* Assume we'll success unless proven otherwise. */
2404 /* No action is needed in this case. */
2410 case FIX_TRUNC_EXPR:
2411 case VIEW_CONVERT_EXPR:
2413 = build1 (code, type,
2414 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2419 case UNCONSTRAINED_ARRAY_REF:
2420 result = build1 (code, type,
2421 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
2426 result = build3 (COMPONENT_REF, type,
2427 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2429 TREE_OPERAND (ref, 1), NULL_TREE);
2433 result = build3 (BIT_FIELD_REF, type,
2434 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2436 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2438 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
2443 case ARRAY_RANGE_REF:
2444 result = build4 (code, type,
2445 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2447 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2449 NULL_TREE, NULL_TREE);
2453 result = gnat_stabilize_reference_1 (ref, force);
2457 result = build2 (COMPOUND_EXPR, type,
2458 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2460 gnat_stabilize_reference (TREE_OPERAND (ref, 1), force,
2465 /* Constructors with 1 element are used extensively to formally
2466 convert objects to special wrapping types. */
2467 if (TREE_CODE (type) == RECORD_TYPE
2468 && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
2471 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
2473 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
2475 = build_constructor_single (type, index,
2476 gnat_stabilize_reference_1 (value,
2488 ref = error_mark_node;
2490 /* ... fall through to failure ... */
2492 /* If arg isn't a kind of lvalue we recognize, make no change.
2493 Caller should recognize the error for an invalid lvalue. */
2500 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2501 may not be sustained across some paths, such as the way via build1 for
2502 INDIRECT_REF. We reset those flags here in the general case, which is
2503 consistent with the GCC version of this routine.
2505 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2506 paths introduce side-effects where there was none initially (e.g. if a
2507 SAVE_EXPR is built) and we also want to keep track of that. */
2508 TREE_READONLY (result) = TREE_READONLY (ref);
2509 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
2510 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
2512 if (code == INDIRECT_REF || code == ARRAY_REF || code == ARRAY_RANGE_REF)
2513 TREE_THIS_NOTRAP (result) = TREE_THIS_NOTRAP (ref);