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 static tree find_common_type (tree, tree);
52 static tree compare_arrays (tree, tree, tree);
53 static tree nonbinary_modular_operation (enum tree_code, tree, tree, tree);
54 static tree build_simple_component_ref (tree, tree, tree, bool);
56 /* Return the base type of TYPE. */
59 get_base_type (tree type)
61 if (TREE_CODE (type) == RECORD_TYPE
62 && TYPE_JUSTIFIED_MODULAR_P (type))
63 type = TREE_TYPE (TYPE_FIELDS (type));
65 while (TREE_TYPE (type)
66 && (TREE_CODE (type) == INTEGER_TYPE
67 || TREE_CODE (type) == REAL_TYPE))
68 type = TREE_TYPE (type);
73 /* EXP is a GCC tree representing an address. See if we can find how
74 strictly the object at that address is aligned. Return that alignment
75 in bits. If we don't know anything about the alignment, return 0. */
78 known_alignment (tree exp)
80 unsigned int this_alignment;
81 unsigned int lhs, rhs;
83 switch (TREE_CODE (exp))
86 case VIEW_CONVERT_EXPR:
88 /* Conversions between pointers and integers don't change the alignment
89 of the underlying object. */
90 this_alignment = known_alignment (TREE_OPERAND (exp, 0));
94 /* The value of a COMPOUND_EXPR is that of it's second operand. */
95 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
100 /* If two address are added, the alignment of the result is the
101 minimum of the two alignments. */
102 lhs = known_alignment (TREE_OPERAND (exp, 0));
103 rhs = known_alignment (TREE_OPERAND (exp, 1));
104 this_alignment = MIN (lhs, rhs);
107 case POINTER_PLUS_EXPR:
108 lhs = known_alignment (TREE_OPERAND (exp, 0));
109 rhs = known_alignment (TREE_OPERAND (exp, 1));
110 /* If we don't know the alignment of the offset, we assume that
113 this_alignment = lhs;
115 this_alignment = MIN (lhs, rhs);
119 /* If there is a choice between two values, use the smallest one. */
120 lhs = known_alignment (TREE_OPERAND (exp, 1));
121 rhs = known_alignment (TREE_OPERAND (exp, 2));
122 this_alignment = MIN (lhs, rhs);
127 unsigned HOST_WIDE_INT c = TREE_INT_CST_LOW (exp);
128 /* The first part of this represents the lowest bit in the constant,
129 but it is originally in bytes, not bits. */
130 this_alignment = MIN (BITS_PER_UNIT * (c & -c), BIGGEST_ALIGNMENT);
135 /* If we know the alignment of just one side, use it. Otherwise,
136 use the product of the alignments. */
137 lhs = known_alignment (TREE_OPERAND (exp, 0));
138 rhs = known_alignment (TREE_OPERAND (exp, 1));
141 this_alignment = rhs;
143 this_alignment = lhs;
145 this_alignment = MIN (lhs * rhs, BIGGEST_ALIGNMENT);
149 /* A bit-and expression is as aligned as the maximum alignment of the
150 operands. We typically get here for a complex lhs and a constant
151 negative power of two on the rhs to force an explicit alignment, so
152 don't bother looking at the lhs. */
153 this_alignment = known_alignment (TREE_OPERAND (exp, 1));
157 this_alignment = expr_align (TREE_OPERAND (exp, 0));
162 tree t = maybe_inline_call_in_expr (exp);
164 return known_alignment (t);
167 /* Fall through... */
170 /* For other pointer expressions, we assume that the pointed-to object
171 is at least as aligned as the pointed-to type. Beware that we can
172 have a dummy type here (e.g. a Taft Amendment type), for which the
173 alignment is meaningless and should be ignored. */
174 if (POINTER_TYPE_P (TREE_TYPE (exp))
175 && !TYPE_IS_DUMMY_P (TREE_TYPE (TREE_TYPE (exp))))
176 this_alignment = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp)));
182 return this_alignment;
185 /* We have a comparison or assignment operation on two types, T1 and T2, which
186 are either both array types or both record types. T1 is assumed to be for
187 the left hand side operand, and T2 for the right hand side. Return the
188 type that both operands should be converted to for the operation, if any.
189 Otherwise return zero. */
192 find_common_type (tree t1, tree t2)
194 /* ??? As of today, various constructs lead here with types of different
195 sizes even when both constants (e.g. tagged types, packable vs regular
196 component types, padded vs unpadded types, ...). While some of these
197 would better be handled upstream (types should be made consistent before
198 calling into build_binary_op), some others are really expected and we
199 have to be careful. */
201 /* We must prevent writing more than what the target may hold if this is for
202 an assignment and the case of tagged types is handled in build_binary_op
203 so use the lhs type if it is known to be smaller, or of constant size and
204 the rhs type is not, whatever the modes. We also force t1 in case of
205 constant size equality to minimize occurrences of view conversions on the
206 lhs of assignments. */
207 if (TREE_CONSTANT (TYPE_SIZE (t1))
208 && (!TREE_CONSTANT (TYPE_SIZE (t2))
209 || !tree_int_cst_lt (TYPE_SIZE (t2), TYPE_SIZE (t1))))
212 /* Otherwise, if the lhs type is non-BLKmode, use it. Note that we know
213 that we will not have any alignment problems since, if we did, the
214 non-BLKmode type could not have been used. */
215 if (TYPE_MODE (t1) != BLKmode)
218 /* If the rhs type is of constant size, use it whatever the modes. At
219 this point it is known to be smaller, or of constant size and the
221 if (TREE_CONSTANT (TYPE_SIZE (t2)))
224 /* Otherwise, if the rhs type is non-BLKmode, use it. */
225 if (TYPE_MODE (t2) != BLKmode)
228 /* In this case, both types have variable size and BLKmode. It's
229 probably best to leave the "type mismatch" because changing it
230 could cause a bad self-referential reference. */
234 /* Return an expression tree representing an equality comparison of A1 and A2,
235 two objects of type ARRAY_TYPE. The result should be of type RESULT_TYPE.
237 Two arrays are equal in one of two ways: (1) if both have zero length in
238 some dimension (not necessarily the same dimension) or (2) if the lengths
239 in each dimension are equal and the data is equal. We perform the length
240 tests in as efficient a manner as possible. */
243 compare_arrays (tree result_type, tree a1, tree a2)
245 tree result = convert (result_type, boolean_true_node);
246 tree a1_is_null = convert (result_type, boolean_false_node);
247 tree a2_is_null = convert (result_type, boolean_false_node);
248 tree t1 = TREE_TYPE (a1);
249 tree t2 = TREE_TYPE (a2);
250 tree result = convert (result_type, integer_one_node);
251 tree a1_is_null = convert (result_type, integer_zero_node);
252 tree a2_is_null = convert (result_type, integer_zero_node);
253 bool a1_side_effects_p = TREE_SIDE_EFFECTS (a1);
254 bool a2_side_effects_p = TREE_SIDE_EFFECTS (a2);
255 bool length_zero_p = false;
257 /* If either operand has side-effects, they have to be evaluated only once
258 in spite of the multiple references to the operand in the comparison. */
259 if (a1_side_effects_p)
260 a1 = gnat_protect_expr (a1);
262 if (a2_side_effects_p)
263 a2 = gnat_protect_expr (a2);
265 /* Process each dimension separately and compare the lengths. If any
266 dimension has a length known to be zero, set LENGTH_ZERO_P to true
267 in order to suppress the comparison of the data at the end. */
268 while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
270 tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
271 tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
272 tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
273 tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
274 tree bt = get_base_type (TREE_TYPE (lb1));
275 tree length1 = fold_build2 (MINUS_EXPR, bt, ub1, lb1);
276 tree length2 = fold_build2 (MINUS_EXPR, bt, ub2, lb2);
277 tree comparison, this_a1_is_null, this_a2_is_null;
281 /* If the length of the first array is a constant, swap our operands
282 unless the length of the second array is the constant zero. */
283 if (TREE_CODE (length1) == INTEGER_CST && !integer_zerop (length2))
288 tem = a1, a1 = a2, a2 = tem;
289 tem = t1, t1 = t2, t2 = tem;
290 tem = lb1, lb1 = lb2, lb2 = tem;
291 tem = ub1, ub1 = ub2, ub2 = tem;
292 tem = length1, length1 = length2, length2 = tem;
293 tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
294 btem = a1_side_effects_p, a1_side_effects_p = a2_side_effects_p,
295 a2_side_effects_p = btem;
298 /* If the length of the second array is the constant zero, we can just
299 use the original stored bounds for the first array and see whether
300 last < first holds. */
301 if (integer_zerop (length2))
303 length_zero_p = true;
305 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
306 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
308 comparison = build_binary_op (LT_EXPR, result_type, ub1, lb1);
309 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
310 if (EXPR_P (comparison))
311 SET_EXPR_LOCATION (comparison, input_location);
313 this_a1_is_null = comparison;
314 this_a2_is_null = convert (result_type, boolean_true_node);
317 /* Otherwise, if the length is some other constant value, we know that
318 this dimension in the second array cannot be superflat, so we can
319 just use its length computed from the actual stored bounds. */
320 else if (TREE_CODE (length2) == INTEGER_CST)
324 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
325 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
326 /* Note that we know that UB2 and LB2 are constant and hence
327 cannot contain a PLACEHOLDER_EXPR. */
328 ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
329 lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
330 bt = get_base_type (TREE_TYPE (ub1));
333 = build_binary_op (EQ_EXPR, result_type,
334 build_binary_op (MINUS_EXPR, bt, ub1, lb1),
335 build_binary_op (MINUS_EXPR, bt, ub2, lb2));
336 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
337 if (EXPR_P (comparison))
338 SET_EXPR_LOCATION (comparison, input_location);
340 this_a1_is_null = build_binary_op (LT_EXPR, result_type, ub1, lb1);
341 if (EXPR_P (this_a1_is_null))
342 SET_EXPR_LOCATION (this_a1_is_null, input_location);
344 this_a2_is_null = convert (result_type, boolean_false_node);
347 /* Otherwise, compare the computed lengths. */
350 length1 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1, a1);
351 length2 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2, a2);
354 = build_binary_op (EQ_EXPR, result_type, length1, length2);
355 if (EXPR_P (comparison))
356 SET_EXPR_LOCATION (comparison, input_location);
358 /* If the length expression is of the form (cond ? val : 0), assume
359 that cond is equivalent to (length != 0). That's guaranteed by
360 construction of the array types in gnat_to_gnu_entity. */
361 if (TREE_CODE (length1) == COND_EXPR
362 && integer_zerop (TREE_OPERAND (length1, 2)))
363 this_a1_is_null = invert_truthvalue (TREE_OPERAND (length1, 0));
365 this_a1_is_null = build_binary_op (EQ_EXPR, result_type, length1,
367 if (EXPR_P (this_a1_is_null))
368 SET_EXPR_LOCATION (this_a1_is_null, input_location);
370 /* Likewise for the second array. */
371 if (TREE_CODE (length2) == COND_EXPR
372 && integer_zerop (TREE_OPERAND (length2, 2)))
373 this_a2_is_null = invert_truthvalue (TREE_OPERAND (length2, 0));
375 this_a2_is_null = build_binary_op (EQ_EXPR, result_type, length2,
377 if (EXPR_P (this_a2_is_null))
378 SET_EXPR_LOCATION (this_a2_is_null, input_location);
381 /* Append expressions for this dimension to the final expressions. */
382 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
385 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
386 this_a1_is_null, a1_is_null);
388 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
389 this_a2_is_null, a2_is_null);
395 /* Unless the length of some dimension is known to be zero, compare the
396 data in the array. */
399 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
404 a1 = convert (type, a1),
405 a2 = convert (type, a2);
408 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result,
409 fold_build2 (EQ_EXPR, result_type, a1, a2));
412 /* The result is also true if both sizes are zero. */
413 result = build_binary_op (TRUTH_ORIF_EXPR, result_type,
414 build_binary_op (TRUTH_ANDIF_EXPR, result_type,
415 a1_is_null, a2_is_null),
418 /* If either operand has side-effects, they have to be evaluated before
419 starting the comparison above since the place they would be otherwise
420 evaluated could be wrong. */
421 if (a1_side_effects_p)
422 result = build2 (COMPOUND_EXPR, result_type, a1, result);
424 if (a2_side_effects_p)
425 result = build2 (COMPOUND_EXPR, result_type, a2, result);
430 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
431 type TYPE. We know that TYPE is a modular type with a nonbinary
435 nonbinary_modular_operation (enum tree_code op_code, tree type, tree lhs,
438 tree modulus = TYPE_MODULUS (type);
439 unsigned int needed_precision = tree_floor_log2 (modulus) + 1;
440 unsigned int precision;
441 bool unsignedp = true;
445 /* If this is an addition of a constant, convert it to a subtraction
446 of a constant since we can do that faster. */
447 if (op_code == PLUS_EXPR && TREE_CODE (rhs) == INTEGER_CST)
449 rhs = fold_build2 (MINUS_EXPR, type, modulus, rhs);
450 op_code = MINUS_EXPR;
453 /* For the logical operations, we only need PRECISION bits. For
454 addition and subtraction, we need one more and for multiplication we
455 need twice as many. But we never want to make a size smaller than
457 if (op_code == PLUS_EXPR || op_code == MINUS_EXPR)
458 needed_precision += 1;
459 else if (op_code == MULT_EXPR)
460 needed_precision *= 2;
462 precision = MAX (needed_precision, TYPE_PRECISION (op_type));
464 /* Unsigned will do for everything but subtraction. */
465 if (op_code == MINUS_EXPR)
468 /* If our type is the wrong signedness or isn't wide enough, make a new
469 type and convert both our operands to it. */
470 if (TYPE_PRECISION (op_type) < precision
471 || TYPE_UNSIGNED (op_type) != unsignedp)
473 /* Copy the node so we ensure it can be modified to make it modular. */
474 op_type = copy_node (gnat_type_for_size (precision, unsignedp));
475 modulus = convert (op_type, modulus);
476 SET_TYPE_MODULUS (op_type, modulus);
477 TYPE_MODULAR_P (op_type) = 1;
478 lhs = convert (op_type, lhs);
479 rhs = convert (op_type, rhs);
482 /* Do the operation, then we'll fix it up. */
483 result = fold_build2 (op_code, op_type, lhs, rhs);
485 /* For multiplication, we have no choice but to do a full modulus
486 operation. However, we want to do this in the narrowest
488 if (op_code == MULT_EXPR)
490 tree div_type = copy_node (gnat_type_for_size (needed_precision, 1));
491 modulus = convert (div_type, modulus);
492 SET_TYPE_MODULUS (div_type, modulus);
493 TYPE_MODULAR_P (div_type) = 1;
494 result = convert (op_type,
495 fold_build2 (TRUNC_MOD_EXPR, div_type,
496 convert (div_type, result), modulus));
499 /* For subtraction, add the modulus back if we are negative. */
500 else if (op_code == MINUS_EXPR)
502 result = gnat_protect_expr (result);
503 result = fold_build3 (COND_EXPR, op_type,
504 fold_build2 (LT_EXPR, boolean_type_node, result,
505 convert (op_type, integer_zero_node)),
506 fold_build2 (PLUS_EXPR, op_type, result, modulus),
510 /* For the other operations, subtract the modulus if we are >= it. */
513 result = gnat_protect_expr (result);
514 result = fold_build3 (COND_EXPR, op_type,
515 fold_build2 (GE_EXPR, boolean_type_node,
517 fold_build2 (MINUS_EXPR, op_type,
522 return convert (type, result);
525 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
526 desired for the result. Usually the operation is to be performed
527 in that type. For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
528 in which case the type to be used will be derived from the operands.
530 This function is very much unlike the ones for C and C++ since we
531 have already done any type conversion and matching required. All we
532 have to do here is validate the work done by SEM and handle subtypes. */
535 build_binary_op (enum tree_code op_code, tree result_type,
536 tree left_operand, tree right_operand)
538 tree left_type = TREE_TYPE (left_operand);
539 tree right_type = TREE_TYPE (right_operand);
540 tree left_base_type = get_base_type (left_type);
541 tree right_base_type = get_base_type (right_type);
542 tree operation_type = result_type;
543 tree best_type = NULL_TREE;
544 tree modulus, result;
545 bool has_side_effects = false;
548 && TREE_CODE (operation_type) == RECORD_TYPE
549 && TYPE_JUSTIFIED_MODULAR_P (operation_type))
550 operation_type = TREE_TYPE (TYPE_FIELDS (operation_type));
553 && !AGGREGATE_TYPE_P (operation_type)
554 && TYPE_EXTRA_SUBTYPE_P (operation_type))
555 operation_type = get_base_type (operation_type);
557 modulus = (operation_type
558 && TREE_CODE (operation_type) == INTEGER_TYPE
559 && TYPE_MODULAR_P (operation_type)
560 ? TYPE_MODULUS (operation_type) : NULL_TREE);
566 /* If there were integral or pointer conversions on the LHS, remove
567 them; we'll be putting them back below if needed. Likewise for
568 conversions between array and record types, except for justified
569 modular types. But don't do this if the right operand is not
570 BLKmode (for packed arrays) unless we are not changing the mode. */
571 while ((CONVERT_EXPR_P (left_operand)
572 || TREE_CODE (left_operand) == VIEW_CONVERT_EXPR)
573 && (((INTEGRAL_TYPE_P (left_type)
574 || POINTER_TYPE_P (left_type))
575 && (INTEGRAL_TYPE_P (TREE_TYPE
576 (TREE_OPERAND (left_operand, 0)))
577 || POINTER_TYPE_P (TREE_TYPE
578 (TREE_OPERAND (left_operand, 0)))))
579 || (((TREE_CODE (left_type) == RECORD_TYPE
580 && !TYPE_JUSTIFIED_MODULAR_P (left_type))
581 || TREE_CODE (left_type) == ARRAY_TYPE)
582 && ((TREE_CODE (TREE_TYPE
583 (TREE_OPERAND (left_operand, 0)))
585 || (TREE_CODE (TREE_TYPE
586 (TREE_OPERAND (left_operand, 0)))
588 && (TYPE_MODE (right_type) == BLKmode
589 || (TYPE_MODE (left_type)
590 == TYPE_MODE (TREE_TYPE
592 (left_operand, 0))))))))
594 left_operand = TREE_OPERAND (left_operand, 0);
595 left_type = TREE_TYPE (left_operand);
598 /* If a class-wide type may be involved, force use of the RHS type. */
599 if ((TREE_CODE (right_type) == RECORD_TYPE
600 || TREE_CODE (right_type) == UNION_TYPE)
601 && TYPE_ALIGN_OK (right_type))
602 operation_type = right_type;
604 /* If we are copying between padded objects with compatible types, use
605 the padded view of the objects, this is very likely more efficient.
606 Likewise for a padded object that is assigned a constructor, if we
607 can convert the constructor to the inner type, to avoid putting a
608 VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
609 actually copied anything. */
610 else if (TYPE_IS_PADDING_P (left_type)
611 && TREE_CONSTANT (TYPE_SIZE (left_type))
612 && ((TREE_CODE (right_operand) == COMPONENT_REF
614 (TREE_TYPE (TREE_OPERAND (right_operand, 0)))
615 && gnat_types_compatible_p
617 TREE_TYPE (TREE_OPERAND (right_operand, 0))))
618 || (TREE_CODE (right_operand) == CONSTRUCTOR
619 && !CONTAINS_PLACEHOLDER_P
620 (DECL_SIZE (TYPE_FIELDS (left_type)))))
621 && !integer_zerop (TYPE_SIZE (right_type)))
622 operation_type = left_type;
624 /* Find the best type to use for copying between aggregate types. */
625 else if (((TREE_CODE (left_type) == ARRAY_TYPE
626 && TREE_CODE (right_type) == ARRAY_TYPE)
627 || (TREE_CODE (left_type) == RECORD_TYPE
628 && TREE_CODE (right_type) == RECORD_TYPE))
629 && (best_type = find_common_type (left_type, right_type)))
630 operation_type = best_type;
632 /* Otherwise use the LHS type. */
633 else if (!operation_type)
634 operation_type = left_type;
636 /* Ensure everything on the LHS is valid. If we have a field reference,
637 strip anything that get_inner_reference can handle. Then remove any
638 conversions between types having the same code and mode. And mark
639 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
640 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
641 result = left_operand;
644 tree restype = TREE_TYPE (result);
646 if (TREE_CODE (result) == COMPONENT_REF
647 || TREE_CODE (result) == ARRAY_REF
648 || TREE_CODE (result) == ARRAY_RANGE_REF)
649 while (handled_component_p (result))
650 result = TREE_OPERAND (result, 0);
651 else if (TREE_CODE (result) == REALPART_EXPR
652 || TREE_CODE (result) == IMAGPART_EXPR
653 || (CONVERT_EXPR_P (result)
654 && (((TREE_CODE (restype)
655 == TREE_CODE (TREE_TYPE
656 (TREE_OPERAND (result, 0))))
657 && (TYPE_MODE (TREE_TYPE
658 (TREE_OPERAND (result, 0)))
659 == TYPE_MODE (restype)))
660 || TYPE_ALIGN_OK (restype))))
661 result = TREE_OPERAND (result, 0);
662 else if (TREE_CODE (result) == VIEW_CONVERT_EXPR)
664 TREE_ADDRESSABLE (result) = 1;
665 result = TREE_OPERAND (result, 0);
671 gcc_assert (TREE_CODE (result) == INDIRECT_REF
672 || TREE_CODE (result) == NULL_EXPR
675 /* Convert the right operand to the operation type unless it is
676 either already of the correct type or if the type involves a
677 placeholder, since the RHS may not have the same record type. */
678 if (operation_type != right_type
679 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type)))
681 right_operand = convert (operation_type, right_operand);
682 right_type = operation_type;
685 /* If the left operand is not of the same type as the operation
686 type, wrap it up in a VIEW_CONVERT_EXPR. */
687 if (left_type != operation_type)
688 left_operand = unchecked_convert (operation_type, left_operand, false);
690 has_side_effects = true;
696 operation_type = TREE_TYPE (left_type);
698 /* ... fall through ... */
700 case ARRAY_RANGE_REF:
701 /* First look through conversion between type variants. Note that
702 this changes neither the operation type nor the type domain. */
703 if (TREE_CODE (left_operand) == VIEW_CONVERT_EXPR
704 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand, 0)))
705 == TYPE_MAIN_VARIANT (left_type))
707 left_operand = TREE_OPERAND (left_operand, 0);
708 left_type = TREE_TYPE (left_operand);
711 /* For a range, make sure the element type is consistent. */
712 if (op_code == ARRAY_RANGE_REF
713 && TREE_TYPE (operation_type) != TREE_TYPE (left_type))
714 operation_type = build_array_type (TREE_TYPE (left_type),
715 TYPE_DOMAIN (operation_type));
717 /* Then convert the right operand to its base type. This will prevent
718 unneeded sign conversions when sizetype is wider than integer. */
719 right_operand = convert (right_base_type, right_operand);
720 right_operand = convert (sizetype, right_operand);
722 if (!TREE_CONSTANT (right_operand)
723 || !TREE_CONSTANT (TYPE_MIN_VALUE (right_type)))
724 gnat_mark_addressable (left_operand);
729 case TRUTH_ANDIF_EXPR:
730 case TRUTH_ORIF_EXPR:
734 #ifdef ENABLE_CHECKING
735 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
737 operation_type = left_base_type;
738 left_operand = convert (operation_type, left_operand);
739 right_operand = convert (operation_type, right_operand);
748 #ifdef ENABLE_CHECKING
749 gcc_assert (TREE_CODE (get_base_type (result_type)) == BOOLEAN_TYPE);
751 /* If either operand is a NULL_EXPR, just return a new one. */
752 if (TREE_CODE (left_operand) == NULL_EXPR)
753 return build2 (op_code, result_type,
754 build1 (NULL_EXPR, integer_type_node,
755 TREE_OPERAND (left_operand, 0)),
758 else if (TREE_CODE (right_operand) == NULL_EXPR)
759 return build2 (op_code, result_type,
760 build1 (NULL_EXPR, integer_type_node,
761 TREE_OPERAND (right_operand, 0)),
764 /* If either object is a justified modular types, get the
765 fields from within. */
766 if (TREE_CODE (left_type) == RECORD_TYPE
767 && TYPE_JUSTIFIED_MODULAR_P (left_type))
769 left_operand = convert (TREE_TYPE (TYPE_FIELDS (left_type)),
771 left_type = TREE_TYPE (left_operand);
772 left_base_type = get_base_type (left_type);
775 if (TREE_CODE (right_type) == RECORD_TYPE
776 && TYPE_JUSTIFIED_MODULAR_P (right_type))
778 right_operand = convert (TREE_TYPE (TYPE_FIELDS (right_type)),
780 right_type = TREE_TYPE (right_operand);
781 right_base_type = get_base_type (right_type);
784 /* If both objects are arrays, compare them specially. */
785 if ((TREE_CODE (left_type) == ARRAY_TYPE
786 || (TREE_CODE (left_type) == INTEGER_TYPE
787 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type)))
788 && (TREE_CODE (right_type) == ARRAY_TYPE
789 || (TREE_CODE (right_type) == INTEGER_TYPE
790 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type))))
792 result = compare_arrays (result_type, left_operand, right_operand);
794 if (op_code == NE_EXPR)
795 result = invert_truthvalue (result);
797 gcc_assert (op_code == EQ_EXPR);
802 /* Otherwise, the base types must be the same, unless they are both fat
803 pointer types or record types. In the latter case, use the best type
804 and convert both operands to that type. */
805 if (left_base_type != right_base_type)
807 if (TYPE_IS_FAT_POINTER_P (left_base_type)
808 && TYPE_IS_FAT_POINTER_P (right_base_type))
810 gcc_assert (TYPE_MAIN_VARIANT (left_base_type)
811 == TYPE_MAIN_VARIANT (right_base_type));
812 best_type = left_base_type;
815 else if (TREE_CODE (left_base_type) == RECORD_TYPE
816 && TREE_CODE (right_base_type) == RECORD_TYPE)
818 /* The only way this is permitted is if both types have the same
819 name. In that case, one of them must not be self-referential.
820 Use it as the best type. Even better with a fixed size. */
821 gcc_assert (TYPE_NAME (left_base_type)
822 && TYPE_NAME (left_base_type)
823 == TYPE_NAME (right_base_type));
825 if (TREE_CONSTANT (TYPE_SIZE (left_base_type)))
826 best_type = left_base_type;
827 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type)))
828 best_type = right_base_type;
829 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type)))
830 best_type = left_base_type;
831 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type)))
832 best_type = right_base_type;
840 left_operand = convert (best_type, left_operand);
841 right_operand = convert (best_type, right_operand);
845 left_operand = convert (left_base_type, left_operand);
846 right_operand = convert (right_base_type, right_operand);
849 /* If we are comparing a fat pointer against zero, we just need to
850 compare the data pointer. */
851 if (TYPE_IS_FAT_POINTER_P (left_base_type)
852 && TREE_CODE (right_operand) == CONSTRUCTOR
853 && integer_zerop (VEC_index (constructor_elt,
854 CONSTRUCTOR_ELTS (right_operand),
858 = build_component_ref (left_operand, NULL_TREE,
859 TYPE_FIELDS (left_base_type), false);
861 = convert (TREE_TYPE (left_operand), integer_zero_node);
871 /* The RHS of a shift can be any type. Also, ignore any modulus
872 (we used to abort, but this is needed for unchecked conversion
873 to modular types). Otherwise, processing is the same as normal. */
874 gcc_assert (operation_type == left_base_type);
876 left_operand = convert (operation_type, left_operand);
882 /* For binary modulus, if the inputs are in range, so are the
884 if (modulus && integer_pow2p (modulus))
889 gcc_assert (TREE_TYPE (result_type) == left_base_type
890 && TREE_TYPE (result_type) == right_base_type);
891 left_operand = convert (left_base_type, left_operand);
892 right_operand = convert (right_base_type, right_operand);
895 case TRUNC_DIV_EXPR: case TRUNC_MOD_EXPR:
896 case CEIL_DIV_EXPR: case CEIL_MOD_EXPR:
897 case FLOOR_DIV_EXPR: case FLOOR_MOD_EXPR:
898 case ROUND_DIV_EXPR: case ROUND_MOD_EXPR:
899 /* These always produce results lower than either operand. */
903 case POINTER_PLUS_EXPR:
904 gcc_assert (operation_type == left_base_type
905 && sizetype == right_base_type);
906 left_operand = convert (operation_type, left_operand);
907 right_operand = convert (sizetype, right_operand);
910 case PLUS_NOMOD_EXPR:
911 case MINUS_NOMOD_EXPR:
912 if (op_code == PLUS_NOMOD_EXPR)
915 op_code = MINUS_EXPR;
918 /* ... fall through ... */
922 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
923 other compilers. Contrary to C, Ada doesn't allow arithmetics in
924 these types but can generate addition/subtraction for Succ/Pred. */
926 && (TREE_CODE (operation_type) == ENUMERAL_TYPE
927 || TREE_CODE (operation_type) == BOOLEAN_TYPE))
928 operation_type = left_base_type = right_base_type
929 = gnat_type_for_mode (TYPE_MODE (operation_type),
930 TYPE_UNSIGNED (operation_type));
932 /* ... fall through ... */
936 /* The result type should be the same as the base types of the
937 both operands (and they should be the same). Convert
938 everything to the result type. */
940 gcc_assert (operation_type == left_base_type
941 && left_base_type == right_base_type);
942 left_operand = convert (operation_type, left_operand);
943 right_operand = convert (operation_type, right_operand);
946 if (modulus && !integer_pow2p (modulus))
948 result = nonbinary_modular_operation (op_code, operation_type,
949 left_operand, right_operand);
952 /* If either operand is a NULL_EXPR, just return a new one. */
953 else if (TREE_CODE (left_operand) == NULL_EXPR)
954 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (left_operand, 0));
955 else if (TREE_CODE (right_operand) == NULL_EXPR)
956 return build1 (NULL_EXPR, operation_type, TREE_OPERAND (right_operand, 0));
957 else if (op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
958 result = fold (build4 (op_code, operation_type, left_operand,
959 right_operand, NULL_TREE, NULL_TREE));
962 = fold_build2 (op_code, operation_type, left_operand, right_operand);
964 TREE_SIDE_EFFECTS (result) |= has_side_effects;
965 TREE_CONSTANT (result)
966 |= (TREE_CONSTANT (left_operand) & TREE_CONSTANT (right_operand)
967 && op_code != ARRAY_REF && op_code != ARRAY_RANGE_REF);
969 if ((op_code == ARRAY_REF || op_code == ARRAY_RANGE_REF)
970 && TYPE_VOLATILE (operation_type))
971 TREE_THIS_VOLATILE (result) = 1;
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 (operand);
1025 case ATTR_ADDR_EXPR:
1027 switch (TREE_CODE (operand))
1030 case UNCONSTRAINED_ARRAY_REF:
1031 result = TREE_OPERAND (operand, 0);
1033 /* Make sure the type here is a pointer, not a reference.
1034 GCC wants pointer types for function addresses. */
1036 result_type = build_pointer_type (type);
1038 /* If the underlying object can alias everything, propagate the
1039 property since we are effectively retrieving the object. */
1040 if (POINTER_TYPE_P (TREE_TYPE (result))
1041 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result)))
1043 if (TREE_CODE (result_type) == POINTER_TYPE
1044 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1046 = build_pointer_type_for_mode (TREE_TYPE (result_type),
1047 TYPE_MODE (result_type),
1049 else if (TREE_CODE (result_type) == REFERENCE_TYPE
1050 && !TYPE_REF_CAN_ALIAS_ALL (result_type))
1052 = build_reference_type_for_mode (TREE_TYPE (result_type),
1053 TYPE_MODE (result_type),
1060 TREE_TYPE (result) = type = build_pointer_type (type);
1064 /* Fold a compound expression if it has unconstrained array type
1065 since the middle-end cannot handle it. But we don't it in the
1066 general case because it may introduce aliasing issues if the
1067 first operand is an indirect assignment and the second operand
1068 the corresponding address, e.g. for an allocator. */
1069 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
1071 result = build_unary_op (ADDR_EXPR, result_type,
1072 TREE_OPERAND (operand, 1));
1073 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1074 TREE_OPERAND (operand, 0), result);
1080 case ARRAY_RANGE_REF:
1083 /* If this is for 'Address, find the address of the prefix and add
1084 the offset to the field. Otherwise, do this the normal way. */
1085 if (op_code == ATTR_ADDR_EXPR)
1087 HOST_WIDE_INT bitsize;
1088 HOST_WIDE_INT bitpos;
1090 enum machine_mode mode;
1091 int unsignedp, volatilep;
1093 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1094 &mode, &unsignedp, &volatilep,
1097 /* If INNER is a padding type whose field has a self-referential
1098 size, convert to that inner type. We know the offset is zero
1099 and we need to have that type visible. */
1100 if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
1101 && CONTAINS_PLACEHOLDER_P
1102 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1103 (TREE_TYPE (inner))))))
1104 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1107 /* Compute the offset as a byte offset from INNER. */
1109 offset = size_zero_node;
1111 offset = size_binop (PLUS_EXPR, offset,
1112 size_int (bitpos / BITS_PER_UNIT));
1114 /* Take the address of INNER, convert the offset to void *, and
1115 add then. It will later be converted to the desired result
1117 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1118 inner = convert (ptr_void_type_node, inner);
1119 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1121 result = convert (build_pointer_type (TREE_TYPE (operand)),
1128 /* If this is just a constructor for a padded record, we can
1129 just take the address of the single field and convert it to
1130 a pointer to our type. */
1131 if (TYPE_IS_PADDING_P (type))
1133 result = VEC_index (constructor_elt,
1134 CONSTRUCTOR_ELTS (operand),
1136 result = convert (build_pointer_type (TREE_TYPE (operand)),
1137 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1144 if (AGGREGATE_TYPE_P (type)
1145 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1146 return build_unary_op (ADDR_EXPR, result_type,
1147 TREE_OPERAND (operand, 0));
1149 /* ... fallthru ... */
1151 case VIEW_CONVERT_EXPR:
1152 /* If this just a variant conversion or if the conversion doesn't
1153 change the mode, get the result type from this type and go down.
1154 This is needed for conversions of CONST_DECLs, to eventually get
1155 to the address of their CORRESPONDING_VARs. */
1156 if ((TYPE_MAIN_VARIANT (type)
1157 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1158 || (TYPE_MODE (type) != BLKmode
1159 && (TYPE_MODE (type)
1160 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1161 return build_unary_op (ADDR_EXPR,
1162 (result_type ? result_type
1163 : build_pointer_type (type)),
1164 TREE_OPERAND (operand, 0));
1168 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1170 /* ... fall through ... */
1175 /* If we are taking the address of a padded record whose field is
1176 contains a template, take the address of the template. */
1177 if (TYPE_IS_PADDING_P (type)
1178 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1179 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1181 type = TREE_TYPE (TYPE_FIELDS (type));
1182 operand = convert (type, operand);
1185 gnat_mark_addressable (operand);
1186 result = build_fold_addr_expr (operand);
1189 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1193 /* If we want to refer to an unconstrained array, use the appropriate
1194 expression to do so. This will never survive down to the back-end.
1195 But if TYPE is a thin pointer, first convert to a fat pointer. */
1196 if (TYPE_IS_THIN_POINTER_P (type)
1197 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1200 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1202 type = TREE_TYPE (operand);
1205 if (TYPE_IS_FAT_POINTER_P (type))
1207 result = build1 (UNCONSTRAINED_ARRAY_REF,
1208 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1209 TREE_READONLY (result)
1210 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1213 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1214 else if (TREE_CODE (operand) == ADDR_EXPR)
1215 result = TREE_OPERAND (operand, 0);
1217 /* Otherwise, build and fold the indirect reference. */
1220 result = build_fold_indirect_ref (operand);
1221 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1225 = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1231 tree modulus = ((operation_type
1232 && TREE_CODE (operation_type) == INTEGER_TYPE
1233 && TYPE_MODULAR_P (operation_type))
1234 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1235 int mod_pow2 = modulus && integer_pow2p (modulus);
1237 /* If this is a modular type, there are various possibilities
1238 depending on the operation and whether the modulus is a
1239 power of two or not. */
1243 gcc_assert (operation_type == base_type);
1244 operand = convert (operation_type, operand);
1246 /* The fastest in the negate case for binary modulus is
1247 the straightforward code; the TRUNC_MOD_EXPR below
1248 is an AND operation. */
1249 if (op_code == NEGATE_EXPR && mod_pow2)
1250 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1251 fold_build1 (NEGATE_EXPR, operation_type,
1255 /* For nonbinary negate case, return zero for zero operand,
1256 else return the modulus minus the operand. If the modulus
1257 is a power of two minus one, we can do the subtraction
1258 as an XOR since it is equivalent and faster on most machines. */
1259 else if (op_code == NEGATE_EXPR && !mod_pow2)
1261 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1263 convert (operation_type,
1264 integer_one_node))))
1265 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1268 result = fold_build2 (MINUS_EXPR, operation_type,
1271 result = fold_build3 (COND_EXPR, operation_type,
1272 fold_build2 (NE_EXPR,
1277 integer_zero_node)),
1282 /* For the NOT cases, we need a constant equal to
1283 the modulus minus one. For a binary modulus, we
1284 XOR against the constant and subtract the operand from
1285 that constant for nonbinary modulus. */
1287 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1288 convert (operation_type,
1292 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1295 result = fold_build2 (MINUS_EXPR, operation_type,
1303 /* ... fall through ... */
1306 gcc_assert (operation_type == base_type);
1307 result = fold_build1 (op_code, operation_type,
1308 convert (operation_type, operand));
1313 TREE_SIDE_EFFECTS (result) = 1;
1314 if (TREE_CODE (result) == INDIRECT_REF)
1315 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1318 if (result_type && TREE_TYPE (result) != result_type)
1319 result = convert (result_type, result);
1324 /* Similar, but for COND_EXPR. */
1327 build_cond_expr (tree result_type, tree condition_operand,
1328 tree true_operand, tree false_operand)
1330 bool addr_p = false;
1333 /* The front-end verified that result, true and false operands have
1334 same base type. Convert everything to the result type. */
1335 true_operand = convert (result_type, true_operand);
1336 false_operand = convert (result_type, false_operand);
1338 /* If the result type is unconstrained, take the address of the operands and
1339 then dereference the result. Likewise if the result type is passed by
1340 reference because creating a temporary of this type is not allowed. */
1341 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1342 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type))
1343 || (AGGREGATE_TYPE_P (result_type) && TYPE_BY_REFERENCE_P (result_type)))
1345 result_type = build_pointer_type (result_type);
1346 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1347 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1351 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1352 true_operand, false_operand);
1354 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1355 in both arms, make sure it gets evaluated by moving it ahead of the
1356 conditional expression. This is necessary because it is evaluated
1357 in only one place at run time and would otherwise be uninitialized
1358 in one of the arms. */
1359 true_operand = skip_simple_arithmetic (true_operand);
1360 false_operand = skip_simple_arithmetic (false_operand);
1362 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1363 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1366 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1371 /* Similar, but for RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR
1372 around the assignment of RET_VAL to RET_OBJ. Otherwise just build a bare
1373 RETURN_EXPR around RESULT_OBJ, which may be null in this case. */
1376 build_return_expr (tree ret_obj, tree ret_val)
1382 /* The gimplifier explicitly enforces the following invariant:
1391 As a consequence, type consistency dictates that we use the type
1392 of the RET_OBJ as the operation type. */
1393 tree operation_type = TREE_TYPE (ret_obj);
1395 /* Convert the right operand to the operation type. Note that it's the
1396 same transformation as in the MODIFY_EXPR case of build_binary_op,
1397 with the assumption that the type cannot involve a placeholder. */
1398 if (operation_type != TREE_TYPE (ret_val))
1399 ret_val = convert (operation_type, ret_val);
1401 result_expr = build2 (MODIFY_EXPR, operation_type, ret_obj, ret_val);
1404 result_expr = ret_obj;
1406 return build1 (RETURN_EXPR, void_type_node, result_expr);
1409 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1413 build_call_1_expr (tree fundecl, tree arg)
1415 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1416 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1418 TREE_SIDE_EFFECTS (call) = 1;
1422 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1426 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1428 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1429 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1431 TREE_SIDE_EFFECTS (call) = 1;
1435 /* Likewise to call FUNDECL with no arguments. */
1438 build_call_0_expr (tree fundecl)
1440 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1441 it possible to propagate DECL_IS_PURE on parameterless functions. */
1442 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1443 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1448 /* Call a function that raises an exception and pass the line number and file
1449 name, if requested. MSG says which exception function to call.
1451 GNAT_NODE is the gnat node conveying the source location for which the
1452 error should be signaled, or Empty in which case the error is signaled on
1453 the current ref_file_name/input_line.
1455 KIND says which kind of exception this is for
1456 (N_Raise_{Constraint,Storage,Program}_Error). */
1459 build_call_raise (int msg, Node_Id gnat_node, char kind)
1461 tree fndecl = gnat_raise_decls[msg];
1462 tree label = get_exception_label (kind);
1468 /* If this is to be done as a goto, handle that case. */
1471 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1472 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1474 /* If Local_Raise is present, generate
1475 Local_Raise (exception'Identity); */
1476 if (Present (local_raise))
1478 tree gnu_local_raise
1479 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1480 tree gnu_exception_entity
1481 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1483 = build_call_1_expr (gnu_local_raise,
1484 build_unary_op (ADDR_EXPR, NULL_TREE,
1485 gnu_exception_entity));
1487 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1488 gnu_call, gnu_result);}
1494 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1496 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1497 ? IDENTIFIER_POINTER
1498 (get_identifier (Get_Name_String
1500 (Get_Source_File_Index (Sloc (gnat_node))))))
1504 filename = build_string (len, str);
1506 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1507 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1509 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1510 build_index_type (size_int (len)));
1513 build_call_2_expr (fndecl,
1515 build_pointer_type (unsigned_char_type_node),
1517 build_int_cst (NULL_TREE, line_number));
1520 /* qsort comparer for the bit positions of two constructor elements
1521 for record components. */
1524 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1526 const_tree const elmt1 = * (const_tree const *) rt1;
1527 const_tree const elmt2 = * (const_tree const *) rt2;
1528 const_tree const field1 = TREE_PURPOSE (elmt1);
1529 const_tree const field2 = TREE_PURPOSE (elmt2);
1531 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1533 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1536 /* Return a CONSTRUCTOR of TYPE whose list is LIST. */
1539 gnat_build_constructor (tree type, tree list)
1541 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1542 bool side_effects = false;
1546 /* Scan the elements to see if they are all constant or if any has side
1547 effects, to let us set global flags on the resulting constructor. Count
1548 the elements along the way for possible sorting purposes below. */
1549 for (n_elmts = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), n_elmts ++)
1551 tree obj = TREE_PURPOSE (elmt);
1552 tree val = TREE_VALUE (elmt);
1554 /* The predicate must be in keeping with output_constructor. */
1555 if (!TREE_CONSTANT (val)
1556 || (TREE_CODE (type) == RECORD_TYPE
1557 && CONSTRUCTOR_BITFIELD_P (obj)
1558 && !initializer_constant_valid_for_bitfield_p (val))
1559 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1560 allconstant = false;
1562 if (TREE_SIDE_EFFECTS (val))
1563 side_effects = true;
1566 /* For record types with constant components only, sort field list
1567 by increasing bit position. This is necessary to ensure the
1568 constructor can be output as static data. */
1569 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1571 /* Fill an array with an element tree per index, and ask qsort to order
1572 them according to what a bitpos comparison function says. */
1573 tree *gnu_arr = (tree *) alloca (sizeof (tree) * n_elmts);
1576 for (i = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), i++)
1579 qsort (gnu_arr, n_elmts, sizeof (tree), compare_elmt_bitpos);
1581 /* Then reconstruct the list from the sorted array contents. */
1583 for (i = n_elmts - 1; i >= 0; i--)
1585 TREE_CHAIN (gnu_arr[i]) = list;
1590 result = build_constructor_from_list (type, list);
1591 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1592 TREE_SIDE_EFFECTS (result) = side_effects;
1593 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1597 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1598 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1599 for the field. Don't fold the result if NO_FOLD_P is true.
1601 We also handle the fact that we might have been passed a pointer to the
1602 actual record and know how to look for fields in variant parts. */
1605 build_simple_component_ref (tree record_variable, tree component,
1606 tree field, bool no_fold_p)
1608 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1609 tree ref, inner_variable;
1611 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1612 || TREE_CODE (record_type) == UNION_TYPE
1613 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1614 && TYPE_SIZE (record_type)
1615 && (component != 0) != (field != 0));
1617 /* If no field was specified, look for a field with the specified name
1618 in the current record only. */
1620 for (field = TYPE_FIELDS (record_type); field;
1621 field = TREE_CHAIN (field))
1622 if (DECL_NAME (field) == component)
1628 /* If this field is not in the specified record, see if we can find
1629 something in the record whose original field is the same as this one. */
1630 if (DECL_CONTEXT (field) != record_type)
1631 /* Check if there is a field with name COMPONENT in the record. */
1635 /* First loop thru normal components. */
1636 for (new_field = TYPE_FIELDS (record_type); new_field;
1637 new_field = TREE_CHAIN (new_field))
1638 if (SAME_FIELD_P (field, new_field))
1641 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1642 the component in the first search. Doing this search in 2 steps
1643 is required to avoiding hidden homonymous fields in the
1646 for (new_field = TYPE_FIELDS (record_type); new_field;
1647 new_field = TREE_CHAIN (new_field))
1648 if (DECL_INTERNAL_P (new_field))
1651 = build_simple_component_ref (record_variable,
1652 NULL_TREE, new_field, no_fold_p);
1653 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1666 /* If the field's offset has overflowed, do not attempt to access it
1667 as doing so may trigger sanity checks deeper in the back-end.
1668 Note that we don't need to warn since this will be done on trying
1669 to declare the object. */
1670 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1671 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1674 /* Look through conversion between type variants. Note that this
1675 is transparent as far as the field is concerned. */
1676 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1677 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1679 inner_variable = TREE_OPERAND (record_variable, 0);
1681 inner_variable = record_variable;
1683 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1686 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1687 TREE_READONLY (ref) = 1;
1688 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1689 || TYPE_VOLATILE (record_type))
1690 TREE_THIS_VOLATILE (ref) = 1;
1695 /* The generic folder may punt in this case because the inner array type
1696 can be self-referential, but folding is in fact not problematic. */
1697 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1698 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1700 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1701 unsigned HOST_WIDE_INT idx;
1703 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1713 /* Like build_simple_component_ref, except that we give an error if the
1714 reference could not be found. */
1717 build_component_ref (tree record_variable, tree component,
1718 tree field, bool no_fold_p)
1720 tree ref = build_simple_component_ref (record_variable, component, field,
1726 /* If FIELD was specified, assume this is an invalid user field so raise
1727 Constraint_Error. Otherwise, we have no type to return so abort. */
1729 return build1 (NULL_EXPR, TREE_TYPE (field),
1730 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1731 N_Raise_Constraint_Error));
1734 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1735 identically. Process the case where a GNAT_PROC to call is provided. */
1738 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1739 Entity_Id gnat_proc, Entity_Id gnat_pool)
1741 tree gnu_proc = gnat_to_gnu (gnat_proc);
1742 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1745 /* The storage pools are obviously always tagged types, but the
1746 secondary stack uses the same mechanism and is not tagged. */
1747 if (Is_Tagged_Type (Etype (gnat_pool)))
1749 /* The size is the third parameter; the alignment is the
1751 Entity_Id gnat_size_type
1752 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1753 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1755 tree gnu_pool = gnat_to_gnu (gnat_pool);
1756 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1757 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1759 gnu_size = convert (gnu_size_type, gnu_size);
1760 gnu_align = convert (gnu_size_type, gnu_align);
1762 /* The first arg is always the address of the storage pool; next
1763 comes the address of the object, for a deallocator, then the
1764 size and alignment. */
1766 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1767 gnu_proc_addr, 4, gnu_pool_addr,
1768 gnu_obj, gnu_size, gnu_align);
1770 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1771 gnu_proc_addr, 3, gnu_pool_addr,
1772 gnu_size, gnu_align);
1775 /* Secondary stack case. */
1778 /* The size is the second parameter. */
1779 Entity_Id gnat_size_type
1780 = Etype (Next_Formal (First_Formal (gnat_proc)));
1781 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1783 gnu_size = convert (gnu_size_type, gnu_size);
1785 /* The first arg is the address of the object, for a deallocator,
1788 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1789 gnu_proc_addr, 2, gnu_obj, gnu_size);
1791 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1792 gnu_proc_addr, 1, gnu_size);
1795 TREE_SIDE_EFFECTS (gnu_call) = 1;
1799 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1800 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1801 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1805 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1807 /* When the DATA_TYPE alignment is stricter than what malloc offers
1808 (super-aligned case), we allocate an "aligning" wrapper type and return
1809 the address of its single data field with the malloc's return value
1810 stored just in front. */
1812 unsigned int data_align = TYPE_ALIGN (data_type);
1813 unsigned int default_allocator_alignment
1814 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1817 = ((data_align > default_allocator_alignment)
1818 ? make_aligning_type (data_type, data_align, data_size,
1819 default_allocator_alignment,
1820 POINTER_SIZE / BITS_PER_UNIT)
1824 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1828 /* On VMS, if 64-bit memory is disabled or pointers are 64-bit and the
1829 allocator size is 32-bit or Convention C, allocate 32-bit memory. */
1830 if (TARGET_ABI_OPEN_VMS
1831 && (!TARGET_MALLOC64
1832 || (POINTER_SIZE == 64
1833 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1834 || Convention (Etype (gnat_node)) == Convention_C))))
1835 malloc_ptr = build_call_1_expr (malloc32_decl, size_to_malloc);
1837 malloc_ptr = build_call_1_expr (malloc_decl, size_to_malloc);
1841 /* Latch malloc's return value and get a pointer to the aligning field
1843 tree storage_ptr = gnat_protect_expr (malloc_ptr);
1845 tree aligning_record_addr
1846 = convert (build_pointer_type (aligning_type), storage_ptr);
1848 tree aligning_record
1849 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1852 = build_component_ref (aligning_record, NULL_TREE,
1853 TYPE_FIELDS (aligning_type), false);
1855 tree aligning_field_addr
1856 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1858 /* Then arrange to store the allocator's return value ahead
1860 tree storage_ptr_slot_addr
1861 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1862 convert (ptr_void_type_node, aligning_field_addr),
1863 size_int (-(HOST_WIDE_INT) POINTER_SIZE
1866 tree storage_ptr_slot
1867 = build_unary_op (INDIRECT_REF, NULL_TREE,
1868 convert (build_pointer_type (ptr_void_type_node),
1869 storage_ptr_slot_addr));
1872 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
1873 build_binary_op (MODIFY_EXPR, NULL_TREE,
1874 storage_ptr_slot, storage_ptr),
1875 aligning_field_addr);
1881 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
1882 designated by DATA_PTR using the __gnat_free entry point. */
1885 maybe_wrap_free (tree data_ptr, tree data_type)
1887 /* In the regular alignment case, we pass the data pointer straight to free.
1888 In the superaligned case, we need to retrieve the initial allocator
1889 return value, stored in front of the data block at allocation time. */
1891 unsigned int data_align = TYPE_ALIGN (data_type);
1892 unsigned int default_allocator_alignment
1893 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1897 if (data_align > default_allocator_alignment)
1899 /* DATA_FRONT_PTR (void *)
1900 = (void *)DATA_PTR - (void *)sizeof (void *)) */
1903 (POINTER_PLUS_EXPR, ptr_void_type_node,
1904 convert (ptr_void_type_node, data_ptr),
1905 size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
1907 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
1910 (INDIRECT_REF, NULL_TREE,
1911 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
1914 free_ptr = data_ptr;
1916 return build_call_1_expr (free_decl, free_ptr);
1919 /* Build a GCC tree to call an allocation or deallocation function.
1920 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
1921 generate an allocator.
1923 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
1924 object type, used to determine the to-be-honored address alignment.
1925 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
1926 pool to use. If not present, malloc and free are used. GNAT_NODE is used
1927 to provide an error location for restriction violation messages. */
1930 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
1931 Entity_Id gnat_proc, Entity_Id gnat_pool,
1934 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
1936 /* Explicit proc to call ? This one is assumed to deal with the type
1937 alignment constraints. */
1938 if (Present (gnat_proc))
1939 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
1940 gnat_proc, gnat_pool);
1942 /* Otherwise, object to "free" or "malloc" with possible special processing
1943 for alignments stricter than what the default allocator honors. */
1945 return maybe_wrap_free (gnu_obj, gnu_type);
1948 /* Assert that we no longer can be called with this special pool. */
1949 gcc_assert (gnat_pool != -1);
1951 /* Check that we aren't violating the associated restriction. */
1952 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
1953 Check_No_Implicit_Heap_Alloc (gnat_node);
1955 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
1959 /* Build a GCC tree to correspond to allocating an object of TYPE whose
1960 initial value is INIT, if INIT is nonzero. Convert the expression to
1961 RESULT_TYPE, which must be some type of pointer. Return the tree.
1963 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
1964 the storage pool to use. GNAT_NODE is used to provide an error
1965 location for restriction violation messages. If IGNORE_INIT_TYPE is
1966 true, ignore the type of INIT for the purpose of determining the size;
1967 this will cause the maximum size to be allocated if TYPE is of
1968 self-referential size. */
1971 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
1972 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
1974 tree size = TYPE_SIZE_UNIT (type);
1977 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
1978 if (init && TREE_CODE (init) == NULL_EXPR)
1979 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
1981 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
1982 sizes of the object and its template. Allocate the whole thing and
1983 fill in the parts that are known. */
1984 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
1987 = build_unc_object_type_from_ptr (result_type, type,
1988 get_identifier ("ALLOC"), false);
1989 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
1990 tree storage_ptr_type = build_pointer_type (storage_type);
1992 tree template_cons = NULL_TREE;
1994 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
1997 /* If the size overflows, pass -1 so the allocator will raise
1999 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2000 size = ssize_int (-1);
2002 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2003 gnat_proc, gnat_pool, gnat_node);
2004 storage = convert (storage_ptr_type, gnat_protect_expr (storage));
2006 if (TYPE_IS_PADDING_P (type))
2008 type = TREE_TYPE (TYPE_FIELDS (type));
2010 init = convert (type, init);
2013 /* If there is an initializing expression, make a constructor for
2014 the entire object including the bounds and copy it into the
2015 object. If there is no initializing expression, just set the
2019 template_cons = tree_cons (TREE_CHAIN (TYPE_FIELDS (storage_type)),
2021 template_cons = tree_cons (TYPE_FIELDS (storage_type),
2022 build_template (template_type, type,
2028 build2 (COMPOUND_EXPR, storage_ptr_type,
2030 (MODIFY_EXPR, storage_type,
2031 build_unary_op (INDIRECT_REF, NULL_TREE,
2032 convert (storage_ptr_type, storage)),
2033 gnat_build_constructor (storage_type, template_cons)),
2034 convert (storage_ptr_type, storage)));
2038 (COMPOUND_EXPR, result_type,
2040 (MODIFY_EXPR, template_type,
2042 (build_unary_op (INDIRECT_REF, NULL_TREE,
2043 convert (storage_ptr_type, storage)),
2044 NULL_TREE, TYPE_FIELDS (storage_type), false),
2045 build_template (template_type, type, NULL_TREE)),
2046 convert (result_type, convert (storage_ptr_type, storage)));
2049 /* If we have an initializing expression, see if its size is simpler
2050 than the size from the type. */
2051 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2052 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2053 || CONTAINS_PLACEHOLDER_P (size)))
2054 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2056 /* If the size is still self-referential, reference the initializing
2057 expression, if it is present. If not, this must have been a
2058 call to allocate a library-level object, in which case we use
2059 the maximum size. */
2060 if (CONTAINS_PLACEHOLDER_P (size))
2062 if (!ignore_init_type && init)
2063 size = substitute_placeholder_in_expr (size, init);
2065 size = max_size (size, true);
2068 /* If the size overflows, pass -1 so the allocator will raise
2070 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2071 size = ssize_int (-1);
2073 result = convert (result_type,
2074 build_call_alloc_dealloc (NULL_TREE, size, type,
2075 gnat_proc, gnat_pool,
2078 /* If we have an initial value, protect the new address, assign the value
2079 and return the address with a COMPOUND_EXPR. */
2082 result = gnat_protect_expr (result);
2084 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2086 (MODIFY_EXPR, NULL_TREE,
2087 build_unary_op (INDIRECT_REF,
2088 TREE_TYPE (TREE_TYPE (result)), result),
2093 return convert (result_type, result);
2096 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2097 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2098 how we derive the source location to raise C_E on an out of range
2102 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2104 tree parm_decl = get_gnu_tree (gnat_formal);
2105 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2106 tree const_list = NULL_TREE, field;
2107 const bool do_range_check
2109 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2111 expr = maybe_unconstrained_array (expr);
2112 gnat_mark_addressable (expr);
2114 for (field = TYPE_FIELDS (record_type); field; field = TREE_CHAIN (field))
2116 tree conexpr = convert (TREE_TYPE (field),
2117 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2118 (DECL_INITIAL (field), expr));
2120 /* Check to ensure that only 32-bit pointers are passed in
2121 32-bit descriptors */
2123 && strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2126 = build_pointer_type_for_mode (void_type_node, DImode, false);
2127 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2129 = build_int_cstu (long_integer_type_node, 0x80000000);
2131 add_stmt (build3 (COND_EXPR, void_type_node,
2132 build_binary_op (GE_EXPR, boolean_type_node,
2133 convert (long_integer_type_node,
2136 build_call_raise (CE_Range_Check_Failed,
2138 N_Raise_Constraint_Error),
2141 const_list = tree_cons (field, conexpr, const_list);
2144 return gnat_build_constructor (record_type, nreverse (const_list));
2147 /* Indicate that we need to take the address of T and that it therefore
2148 should not be allocated in a register. Returns true if successful. */
2151 gnat_mark_addressable (tree t)
2154 switch (TREE_CODE (t))
2159 case ARRAY_RANGE_REF:
2162 case VIEW_CONVERT_EXPR:
2163 case NON_LVALUE_EXPR:
2165 t = TREE_OPERAND (t, 0);
2169 TREE_ADDRESSABLE (t) = 1;
2175 TREE_ADDRESSABLE (t) = 1;
2179 TREE_ADDRESSABLE (t) = 1;
2183 return DECL_CONST_CORRESPONDING_VAR (t)
2184 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
2191 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2192 but we know how to handle our own nodes. */
2195 gnat_save_expr (tree exp)
2197 tree type = TREE_TYPE (exp);
2198 enum tree_code code = TREE_CODE (exp);
2200 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2203 if (code == UNCONSTRAINED_ARRAY_REF)
2205 tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
2206 TREE_READONLY (t) = TYPE_READONLY (type);
2210 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2211 This may be more efficient, but will also allow us to more easily find
2212 the match for the PLACEHOLDER_EXPR. */
2213 if (code == COMPONENT_REF
2214 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2215 return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
2216 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2218 return save_expr (exp);
2221 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2222 is optimized under the assumption that EXP's value doesn't change before
2223 its subsequent reuse(s) except through its potential reevaluation. */
2226 gnat_protect_expr (tree exp)
2228 tree type = TREE_TYPE (exp);
2229 enum tree_code code = TREE_CODE (exp);
2231 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2234 /* If EXP has no side effects, we theoritically don't need to do anything.
2235 However, we may be recursively passed more and more complex expressions
2236 involving checks which will be reused multiple times and eventually be
2237 unshared for gimplification; in order to avoid a complexity explosion
2238 at that point, we protect any expressions more complex than a simple
2239 arithmetic expression. */
2240 if (!TREE_SIDE_EFFECTS (exp)
2241 && !EXPRESSION_CLASS_P (skip_simple_arithmetic (exp)))
2244 /* If this is a conversion, protect what's inside the conversion. */
2245 if (code == NON_LVALUE_EXPR
2246 || CONVERT_EXPR_CODE_P (code)
2247 || code == VIEW_CONVERT_EXPR)
2248 return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2250 /* If we're indirectly referencing something, we only need to protect the
2251 address since the data itself can't change in these situations. */
2252 if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
2254 tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2255 TREE_READONLY (t) = TYPE_READONLY (type);
2259 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2260 This may be more efficient, but will also allow us to more easily find
2261 the match for the PLACEHOLDER_EXPR. */
2262 if (code == COMPONENT_REF
2263 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2264 return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
2265 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2267 /* If this is a fat pointer or something that can be placed in a register,
2268 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2269 returned via invisible reference in most ABIs so the temporary will
2270 directly be filled by the callee. */
2271 if (TYPE_IS_FAT_POINTER_P (type)
2272 || TYPE_MODE (type) != BLKmode
2273 || code == CALL_EXPR)
2274 return save_expr (exp);
2276 /* Otherwise reference, protect the address and dereference. */
2278 build_unary_op (INDIRECT_REF, type,
2279 save_expr (build_unary_op (ADDR_EXPR,
2280 build_reference_type (type),
2284 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2285 argument to force evaluation of everything. */
2288 gnat_stabilize_reference_1 (tree e, bool force)
2290 enum tree_code code = TREE_CODE (e);
2291 tree type = TREE_TYPE (e);
2294 /* We cannot ignore const expressions because it might be a reference
2295 to a const array but whose index contains side-effects. But we can
2296 ignore things that are actual constant or that already have been
2297 handled by this function. */
2298 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2301 switch (TREE_CODE_CLASS (code))
2303 case tcc_exceptional:
2304 case tcc_declaration:
2305 case tcc_comparison:
2306 case tcc_expression:
2309 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2310 fat pointer. This may be more efficient, but will also allow
2311 us to more easily find the match for the PLACEHOLDER_EXPR. */
2312 if (code == COMPONENT_REF
2313 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
2315 = build3 (code, type,
2316 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2317 TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
2318 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2319 so that it will only be evaluated once. */
2320 /* The tcc_reference and tcc_comparison classes could be handled as
2321 below, but it is generally faster to only evaluate them once. */
2322 else if (TREE_SIDE_EFFECTS (e) || force)
2323 return save_expr (e);
2329 /* Recursively stabilize each operand. */
2331 = build2 (code, type,
2332 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2333 gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
2337 /* Recursively stabilize each operand. */
2339 = build1 (code, type,
2340 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
2347 /* See similar handling in gnat_stabilize_reference. */
2348 TREE_READONLY (result) = TREE_READONLY (e);
2349 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
2350 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2355 /* This is equivalent to stabilize_reference in tree.c but we know how to
2356 handle our own nodes and we take extra arguments. FORCE says whether to
2357 force evaluation of everything. We set SUCCESS to true unless we walk
2358 through something we don't know how to stabilize. */
2361 gnat_stabilize_reference (tree ref, bool force, bool *success)
2363 tree type = TREE_TYPE (ref);
2364 enum tree_code code = TREE_CODE (ref);
2367 /* Assume we'll success unless proven otherwise. */
2377 /* No action is needed in this case. */
2383 case FIX_TRUNC_EXPR:
2384 case VIEW_CONVERT_EXPR:
2386 = build1 (code, type,
2387 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2392 case UNCONSTRAINED_ARRAY_REF:
2393 result = build1 (code, type,
2394 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
2399 result = build3 (COMPONENT_REF, type,
2400 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2402 TREE_OPERAND (ref, 1), NULL_TREE);
2406 result = build3 (BIT_FIELD_REF, type,
2407 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2409 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2411 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
2416 case ARRAY_RANGE_REF:
2417 result = build4 (code, type,
2418 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2420 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2422 NULL_TREE, NULL_TREE);
2427 result = gnat_stabilize_reference_1 (ref, force);
2431 /* Constructors with 1 element are used extensively to formally
2432 convert objects to special wrapping types. */
2433 if (TREE_CODE (type) == RECORD_TYPE
2434 && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
2437 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
2439 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
2441 = build_constructor_single (type, index,
2442 gnat_stabilize_reference_1 (value,
2454 ref = error_mark_node;
2456 /* ... fall through to failure ... */
2458 /* If arg isn't a kind of lvalue we recognize, make no change.
2459 Caller should recognize the error for an invalid lvalue. */
2466 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2467 may not be sustained across some paths, such as the way via build1 for
2468 INDIRECT_REF. We reset those flags here in the general case, which is
2469 consistent with the GCC version of this routine.
2471 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2472 paths introduce side-effects where there was none initially (e.g. if a
2473 SAVE_EXPR is built) and we also want to keep track of that. */
2474 TREE_READONLY (result) = TREE_READONLY (ref);
2475 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
2476 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);