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 bool a1_side_effects_p = TREE_SIDE_EFFECTS (a1);
251 bool a2_side_effects_p = TREE_SIDE_EFFECTS (a2);
252 bool length_zero_p = false;
254 /* If either operand has side-effects, they have to be evaluated only once
255 in spite of the multiple references to the operand in the comparison. */
256 if (a1_side_effects_p)
257 a1 = gnat_protect_expr (a1);
259 if (a2_side_effects_p)
260 a2 = gnat_protect_expr (a2);
262 /* Process each dimension separately and compare the lengths. If any
263 dimension has a length known to be zero, set LENGTH_ZERO_P to true
264 in order to suppress the comparison of the data at the end. */
265 while (TREE_CODE (t1) == ARRAY_TYPE && TREE_CODE (t2) == ARRAY_TYPE)
267 tree lb1 = TYPE_MIN_VALUE (TYPE_DOMAIN (t1));
268 tree ub1 = TYPE_MAX_VALUE (TYPE_DOMAIN (t1));
269 tree lb2 = TYPE_MIN_VALUE (TYPE_DOMAIN (t2));
270 tree ub2 = TYPE_MAX_VALUE (TYPE_DOMAIN (t2));
271 tree length1 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub1, lb1),
273 tree length2 = size_binop (PLUS_EXPR, size_binop (MINUS_EXPR, ub2, lb2),
275 tree comparison, this_a1_is_null, this_a2_is_null;
277 /* If the length of the first array is a constant, swap our operands
278 unless the length of the second array is the constant zero. */
279 if (TREE_CODE (length1) == INTEGER_CST && !integer_zerop (length2))
284 tem = a1, a1 = a2, a2 = tem;
285 tem = t1, t1 = t2, t2 = tem;
286 tem = lb1, lb1 = lb2, lb2 = tem;
287 tem = ub1, ub1 = ub2, ub2 = tem;
288 tem = length1, length1 = length2, length2 = tem;
289 tem = a1_is_null, a1_is_null = a2_is_null, a2_is_null = tem;
290 btem = a1_side_effects_p, a1_side_effects_p = a2_side_effects_p,
291 a2_side_effects_p = btem;
294 /* If the length of the second array is the constant zero, we can just
295 use the original stored bounds for the first array and see whether
296 last < first holds. */
297 if (integer_zerop (length2))
299 length_zero_p = true;
301 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
302 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
304 comparison = build_binary_op (LT_EXPR, result_type, ub1, lb1);
305 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
306 if (EXPR_P (comparison))
307 SET_EXPR_LOCATION (comparison, input_location);
309 this_a1_is_null = comparison;
310 this_a2_is_null = convert (result_type, boolean_true_node);
313 /* Otherwise, if the length is some other constant value, we know that
314 this dimension in the second array cannot be superflat, so we can
315 just use its length computed from the actual stored bounds. */
316 else if (TREE_CODE (length2) == INTEGER_CST)
320 ub1 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
321 lb1 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1)));
322 /* Note that we know that UB2 and LB2 are constant and hence
323 cannot contain a PLACEHOLDER_EXPR. */
324 ub2 = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
325 lb2 = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2)));
326 bt = get_base_type (TREE_TYPE (ub1));
329 = build_binary_op (EQ_EXPR, result_type,
330 build_binary_op (MINUS_EXPR, bt, ub1, lb1),
331 build_binary_op (MINUS_EXPR, bt, ub2, lb2));
332 comparison = SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison, a1);
333 if (EXPR_P (comparison))
334 SET_EXPR_LOCATION (comparison, input_location);
336 this_a1_is_null = build_binary_op (LT_EXPR, result_type, ub1, lb1);
337 if (EXPR_P (this_a1_is_null))
338 SET_EXPR_LOCATION (this_a1_is_null, input_location);
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 = build_binary_op (EQ_EXPR, result_type, length1, length2);
351 if (EXPR_P (comparison))
352 SET_EXPR_LOCATION (comparison, input_location);
354 /* If the length expression is of the form (cond ? val : 0), assume
355 that cond is equivalent to (length != 0). That's guaranteed by
356 construction of the array types in gnat_to_gnu_entity. */
357 if (TREE_CODE (length1) == COND_EXPR
358 && integer_zerop (TREE_OPERAND (length1, 2)))
359 this_a1_is_null = invert_truthvalue (TREE_OPERAND (length1, 0));
361 this_a1_is_null = build_binary_op (EQ_EXPR, result_type, length1,
363 if (EXPR_P (this_a1_is_null))
364 SET_EXPR_LOCATION (this_a1_is_null, input_location);
366 /* Likewise for the second array. */
367 if (TREE_CODE (length2) == COND_EXPR
368 && integer_zerop (TREE_OPERAND (length2, 2)))
369 this_a2_is_null = invert_truthvalue (TREE_OPERAND (length2, 0));
371 this_a2_is_null = build_binary_op (EQ_EXPR, result_type, length2,
373 if (EXPR_P (this_a2_is_null))
374 SET_EXPR_LOCATION (this_a2_is_null, input_location);
377 /* Append expressions for this dimension to the final expressions. */
378 result = build_binary_op (TRUTH_ANDIF_EXPR, result_type,
381 a1_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
382 this_a1_is_null, a1_is_null);
384 a2_is_null = build_binary_op (TRUTH_ORIF_EXPR, result_type,
385 this_a2_is_null, a2_is_null);
391 /* Unless the length of some dimension is known to be zero, compare the
392 data in the array. */
395 tree type = find_common_type (TREE_TYPE (a1), TREE_TYPE (a2));
400 a1 = convert (type, a1),
401 a2 = convert (type, a2);
404 comparison = fold_build2 (EQ_EXPR, result_type, a1, a2);
405 if (EXPR_P (comparison))
406 SET_EXPR_LOCATION (comparison, input_location);
409 = build_binary_op (TRUTH_ANDIF_EXPR, result_type, result, comparison);
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
1084 add the offset to the field. Otherwise, do this the normal
1086 if (op_code == ATTR_ADDR_EXPR)
1088 HOST_WIDE_INT bitsize;
1089 HOST_WIDE_INT bitpos;
1091 enum machine_mode mode;
1092 int unsignedp, volatilep;
1094 inner = get_inner_reference (operand, &bitsize, &bitpos, &offset,
1095 &mode, &unsignedp, &volatilep,
1098 /* If INNER is a padding type whose field has a self-referential
1099 size, convert to that inner type. We know the offset is zero
1100 and we need to have that type visible. */
1101 if (TYPE_IS_PADDING_P (TREE_TYPE (inner))
1102 && CONTAINS_PLACEHOLDER_P
1103 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1104 (TREE_TYPE (inner))))))
1105 inner = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner))),
1108 /* Compute the offset as a byte offset from INNER. */
1110 offset = size_zero_node;
1112 if (bitpos % BITS_PER_UNIT != 0)
1114 ("taking address of object not aligned on storage unit?",
1117 offset = size_binop (PLUS_EXPR, offset,
1118 size_int (bitpos / BITS_PER_UNIT));
1120 /* Take the address of INNER, convert the offset to void *, and
1121 add then. It will later be converted to the desired result
1123 inner = build_unary_op (ADDR_EXPR, NULL_TREE, inner);
1124 inner = convert (ptr_void_type_node, inner);
1125 result = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1127 result = convert (build_pointer_type (TREE_TYPE (operand)),
1134 /* If this is just a constructor for a padded record, we can
1135 just take the address of the single field and convert it to
1136 a pointer to our type. */
1137 if (TYPE_IS_PADDING_P (type))
1139 result = VEC_index (constructor_elt,
1140 CONSTRUCTOR_ELTS (operand),
1142 result = convert (build_pointer_type (TREE_TYPE (operand)),
1143 build_unary_op (ADDR_EXPR, NULL_TREE, result));
1150 if (AGGREGATE_TYPE_P (type)
1151 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand, 0))))
1152 return build_unary_op (ADDR_EXPR, result_type,
1153 TREE_OPERAND (operand, 0));
1155 /* ... fallthru ... */
1157 case VIEW_CONVERT_EXPR:
1158 /* If this just a variant conversion or if the conversion doesn't
1159 change the mode, get the result type from this type and go down.
1160 This is needed for conversions of CONST_DECLs, to eventually get
1161 to the address of their CORRESPONDING_VARs. */
1162 if ((TYPE_MAIN_VARIANT (type)
1163 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand, 0))))
1164 || (TYPE_MODE (type) != BLKmode
1165 && (TYPE_MODE (type)
1166 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand, 0))))))
1167 return build_unary_op (ADDR_EXPR,
1168 (result_type ? result_type
1169 : build_pointer_type (type)),
1170 TREE_OPERAND (operand, 0));
1174 operand = DECL_CONST_CORRESPONDING_VAR (operand);
1176 /* ... fall through ... */
1181 /* If we are taking the address of a padded record whose field is
1182 contains a template, take the address of the template. */
1183 if (TYPE_IS_PADDING_P (type)
1184 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type))) == RECORD_TYPE
1185 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type))))
1187 type = TREE_TYPE (TYPE_FIELDS (type));
1188 operand = convert (type, operand);
1191 gnat_mark_addressable (operand);
1192 result = build_fold_addr_expr (operand);
1195 TREE_CONSTANT (result) = staticp (operand) || TREE_CONSTANT (operand);
1199 /* If we want to refer to an unconstrained array, use the appropriate
1200 expression to do so. This will never survive down to the back-end.
1201 But if TYPE is a thin pointer, first convert to a fat pointer. */
1202 if (TYPE_IS_THIN_POINTER_P (type)
1203 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
1206 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))),
1208 type = TREE_TYPE (operand);
1211 if (TYPE_IS_FAT_POINTER_P (type))
1213 result = build1 (UNCONSTRAINED_ARRAY_REF,
1214 TYPE_UNCONSTRAINED_ARRAY (type), operand);
1215 TREE_READONLY (result)
1216 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type));
1219 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1220 else if (TREE_CODE (operand) == ADDR_EXPR)
1221 result = TREE_OPERAND (operand, 0);
1223 /* Otherwise, build and fold the indirect reference. */
1226 result = build_fold_indirect_ref (operand);
1227 TREE_READONLY (result) = TYPE_READONLY (TREE_TYPE (type));
1231 = (!TYPE_IS_FAT_POINTER_P (type) && TYPE_VOLATILE (TREE_TYPE (type)));
1237 tree modulus = ((operation_type
1238 && TREE_CODE (operation_type) == INTEGER_TYPE
1239 && TYPE_MODULAR_P (operation_type))
1240 ? TYPE_MODULUS (operation_type) : NULL_TREE);
1241 int mod_pow2 = modulus && integer_pow2p (modulus);
1243 /* If this is a modular type, there are various possibilities
1244 depending on the operation and whether the modulus is a
1245 power of two or not. */
1249 gcc_assert (operation_type == base_type);
1250 operand = convert (operation_type, operand);
1252 /* The fastest in the negate case for binary modulus is
1253 the straightforward code; the TRUNC_MOD_EXPR below
1254 is an AND operation. */
1255 if (op_code == NEGATE_EXPR && mod_pow2)
1256 result = fold_build2 (TRUNC_MOD_EXPR, operation_type,
1257 fold_build1 (NEGATE_EXPR, operation_type,
1261 /* For nonbinary negate case, return zero for zero operand,
1262 else return the modulus minus the operand. If the modulus
1263 is a power of two minus one, we can do the subtraction
1264 as an XOR since it is equivalent and faster on most machines. */
1265 else if (op_code == NEGATE_EXPR && !mod_pow2)
1267 if (integer_pow2p (fold_build2 (PLUS_EXPR, operation_type,
1269 convert (operation_type,
1270 integer_one_node))))
1271 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1274 result = fold_build2 (MINUS_EXPR, operation_type,
1277 result = fold_build3 (COND_EXPR, operation_type,
1278 fold_build2 (NE_EXPR,
1283 integer_zero_node)),
1288 /* For the NOT cases, we need a constant equal to
1289 the modulus minus one. For a binary modulus, we
1290 XOR against the constant and subtract the operand from
1291 that constant for nonbinary modulus. */
1293 tree cnst = fold_build2 (MINUS_EXPR, operation_type, modulus,
1294 convert (operation_type,
1298 result = fold_build2 (BIT_XOR_EXPR, operation_type,
1301 result = fold_build2 (MINUS_EXPR, operation_type,
1309 /* ... fall through ... */
1312 gcc_assert (operation_type == base_type);
1313 result = fold_build1 (op_code, operation_type,
1314 convert (operation_type, operand));
1319 TREE_SIDE_EFFECTS (result) = 1;
1320 if (TREE_CODE (result) == INDIRECT_REF)
1321 TREE_THIS_VOLATILE (result) = TYPE_VOLATILE (TREE_TYPE (result));
1324 if (result_type && TREE_TYPE (result) != result_type)
1325 result = convert (result_type, result);
1330 /* Similar, but for COND_EXPR. */
1333 build_cond_expr (tree result_type, tree condition_operand,
1334 tree true_operand, tree false_operand)
1336 bool addr_p = false;
1339 /* The front-end verified that result, true and false operands have
1340 same base type. Convert everything to the result type. */
1341 true_operand = convert (result_type, true_operand);
1342 false_operand = convert (result_type, false_operand);
1344 /* If the result type is unconstrained, take the address of the operands and
1345 then dereference the result. Likewise if the result type is passed by
1346 reference, but this is natively handled in the gimplifier. */
1347 if (TREE_CODE (result_type) == UNCONSTRAINED_ARRAY_TYPE
1348 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type)))
1350 result_type = build_pointer_type (result_type);
1351 true_operand = build_unary_op (ADDR_EXPR, result_type, true_operand);
1352 false_operand = build_unary_op (ADDR_EXPR, result_type, false_operand);
1356 result = fold_build3 (COND_EXPR, result_type, condition_operand,
1357 true_operand, false_operand);
1359 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1360 in both arms, make sure it gets evaluated by moving it ahead of the
1361 conditional expression. This is necessary because it is evaluated
1362 in only one place at run time and would otherwise be uninitialized
1363 in one of the arms. */
1364 true_operand = skip_simple_arithmetic (true_operand);
1365 false_operand = skip_simple_arithmetic (false_operand);
1367 if (true_operand == false_operand && TREE_CODE (true_operand) == SAVE_EXPR)
1368 result = build2 (COMPOUND_EXPR, result_type, true_operand, result);
1371 result = build_unary_op (INDIRECT_REF, NULL_TREE, result);
1376 /* Similar, but for RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR
1377 around the assignment of RET_VAL to RET_OBJ. Otherwise just build a bare
1378 RETURN_EXPR around RESULT_OBJ, which may be null in this case. */
1381 build_return_expr (tree ret_obj, tree ret_val)
1387 /* The gimplifier explicitly enforces the following invariant:
1396 As a consequence, type consistency dictates that we use the type
1397 of the RET_OBJ as the operation type. */
1398 tree operation_type = TREE_TYPE (ret_obj);
1400 /* Convert the right operand to the operation type. Note that it's the
1401 same transformation as in the MODIFY_EXPR case of build_binary_op,
1402 with the assumption that the type cannot involve a placeholder. */
1403 if (operation_type != TREE_TYPE (ret_val))
1404 ret_val = convert (operation_type, ret_val);
1406 result_expr = build2 (MODIFY_EXPR, operation_type, ret_obj, ret_val);
1409 result_expr = ret_obj;
1411 return build1 (RETURN_EXPR, void_type_node, result_expr);
1414 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG. Return
1418 build_call_1_expr (tree fundecl, tree arg)
1420 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1421 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1423 TREE_SIDE_EFFECTS (call) = 1;
1427 /* Build a CALL_EXPR to call FUNDECL with two arguments, ARG1 & ARG2. Return
1431 build_call_2_expr (tree fundecl, tree arg1, tree arg2)
1433 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1434 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1436 TREE_SIDE_EFFECTS (call) = 1;
1440 /* Likewise to call FUNDECL with no arguments. */
1443 build_call_0_expr (tree fundecl)
1445 /* We rely on build_call_nary to compute TREE_SIDE_EFFECTS. This makes
1446 it possible to propagate DECL_IS_PURE on parameterless functions. */
1447 tree call = build_call_nary (TREE_TYPE (TREE_TYPE (fundecl)),
1448 build_unary_op (ADDR_EXPR, NULL_TREE, fundecl),
1453 /* Call a function that raises an exception and pass the line number and file
1454 name, if requested. MSG says which exception function to call.
1456 GNAT_NODE is the gnat node conveying the source location for which the
1457 error should be signaled, or Empty in which case the error is signaled on
1458 the current ref_file_name/input_line.
1460 KIND says which kind of exception this is for
1461 (N_Raise_{Constraint,Storage,Program}_Error). */
1464 build_call_raise (int msg, Node_Id gnat_node, char kind)
1466 tree fndecl = gnat_raise_decls[msg];
1467 tree label = get_exception_label (kind);
1473 /* If this is to be done as a goto, handle that case. */
1476 Entity_Id local_raise = Get_Local_Raise_Call_Entity ();
1477 tree gnu_result = build1 (GOTO_EXPR, void_type_node, label);
1479 /* If Local_Raise is present, generate
1480 Local_Raise (exception'Identity); */
1481 if (Present (local_raise))
1483 tree gnu_local_raise
1484 = gnat_to_gnu_entity (local_raise, NULL_TREE, 0);
1485 tree gnu_exception_entity
1486 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg), NULL_TREE, 0);
1488 = build_call_1_expr (gnu_local_raise,
1489 build_unary_op (ADDR_EXPR, NULL_TREE,
1490 gnu_exception_entity));
1492 gnu_result = build2 (COMPOUND_EXPR, void_type_node,
1493 gnu_call, gnu_result);}
1499 = (Debug_Flag_NN || Exception_Locations_Suppressed)
1501 : (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1502 ? IDENTIFIER_POINTER
1503 (get_identifier (Get_Name_String
1505 (Get_Source_File_Index (Sloc (gnat_node))))))
1509 filename = build_string (len, str);
1511 = (gnat_node != Empty && Sloc (gnat_node) != No_Location)
1512 ? Get_Logical_Line_Number (Sloc(gnat_node)) : input_line;
1514 TREE_TYPE (filename) = build_array_type (unsigned_char_type_node,
1515 build_index_type (size_int (len)));
1518 build_call_2_expr (fndecl,
1520 build_pointer_type (unsigned_char_type_node),
1522 build_int_cst (NULL_TREE, line_number));
1525 /* qsort comparer for the bit positions of two constructor elements
1526 for record components. */
1529 compare_elmt_bitpos (const PTR rt1, const PTR rt2)
1531 const_tree const elmt1 = * (const_tree const *) rt1;
1532 const_tree const elmt2 = * (const_tree const *) rt2;
1533 const_tree const field1 = TREE_PURPOSE (elmt1);
1534 const_tree const field2 = TREE_PURPOSE (elmt2);
1536 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
1538 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
1541 /* Return a CONSTRUCTOR of TYPE whose list is LIST. */
1544 gnat_build_constructor (tree type, tree list)
1546 bool allconstant = (TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST);
1547 bool side_effects = false;
1551 /* Scan the elements to see if they are all constant or if any has side
1552 effects, to let us set global flags on the resulting constructor. Count
1553 the elements along the way for possible sorting purposes below. */
1554 for (n_elmts = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), n_elmts ++)
1556 tree obj = TREE_PURPOSE (elmt);
1557 tree val = TREE_VALUE (elmt);
1559 /* The predicate must be in keeping with output_constructor. */
1560 if (!TREE_CONSTANT (val)
1561 || (TREE_CODE (type) == RECORD_TYPE
1562 && CONSTRUCTOR_BITFIELD_P (obj)
1563 && !initializer_constant_valid_for_bitfield_p (val))
1564 || !initializer_constant_valid_p (val, TREE_TYPE (val)))
1565 allconstant = false;
1567 if (TREE_SIDE_EFFECTS (val))
1568 side_effects = true;
1571 /* For record types with constant components only, sort field list
1572 by increasing bit position. This is necessary to ensure the
1573 constructor can be output as static data. */
1574 if (allconstant && TREE_CODE (type) == RECORD_TYPE && n_elmts > 1)
1576 /* Fill an array with an element tree per index, and ask qsort to order
1577 them according to what a bitpos comparison function says. */
1578 tree *gnu_arr = (tree *) alloca (sizeof (tree) * n_elmts);
1581 for (i = 0, elmt = list; elmt; elmt = TREE_CHAIN (elmt), i++)
1584 qsort (gnu_arr, n_elmts, sizeof (tree), compare_elmt_bitpos);
1586 /* Then reconstruct the list from the sorted array contents. */
1588 for (i = n_elmts - 1; i >= 0; i--)
1590 TREE_CHAIN (gnu_arr[i]) = list;
1595 result = build_constructor_from_list (type, list);
1596 TREE_CONSTANT (result) = TREE_STATIC (result) = allconstant;
1597 TREE_SIDE_EFFECTS (result) = side_effects;
1598 TREE_READONLY (result) = TYPE_READONLY (type) || allconstant;
1602 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1603 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1604 for the field. Don't fold the result if NO_FOLD_P is true.
1606 We also handle the fact that we might have been passed a pointer to the
1607 actual record and know how to look for fields in variant parts. */
1610 build_simple_component_ref (tree record_variable, tree component,
1611 tree field, bool no_fold_p)
1613 tree record_type = TYPE_MAIN_VARIANT (TREE_TYPE (record_variable));
1614 tree ref, inner_variable;
1616 gcc_assert ((TREE_CODE (record_type) == RECORD_TYPE
1617 || TREE_CODE (record_type) == UNION_TYPE
1618 || TREE_CODE (record_type) == QUAL_UNION_TYPE)
1619 && TYPE_SIZE (record_type)
1620 && (component != 0) != (field != 0));
1622 /* If no field was specified, look for a field with the specified name
1623 in the current record only. */
1625 for (field = TYPE_FIELDS (record_type); field;
1626 field = TREE_CHAIN (field))
1627 if (DECL_NAME (field) == component)
1633 /* If this field is not in the specified record, see if we can find
1634 something in the record whose original field is the same as this one. */
1635 if (DECL_CONTEXT (field) != record_type)
1636 /* Check if there is a field with name COMPONENT in the record. */
1640 /* First loop thru normal components. */
1641 for (new_field = TYPE_FIELDS (record_type); new_field;
1642 new_field = TREE_CHAIN (new_field))
1643 if (SAME_FIELD_P (field, new_field))
1646 /* Next, loop thru DECL_INTERNAL_P components if we haven't found
1647 the component in the first search. Doing this search in 2 steps
1648 is required to avoiding hidden homonymous fields in the
1651 for (new_field = TYPE_FIELDS (record_type); new_field;
1652 new_field = TREE_CHAIN (new_field))
1653 if (DECL_INTERNAL_P (new_field))
1656 = build_simple_component_ref (record_variable,
1657 NULL_TREE, new_field, no_fold_p);
1658 ref = build_simple_component_ref (field_ref, NULL_TREE, field,
1671 /* If the field's offset has overflowed, do not attempt to access it
1672 as doing so may trigger sanity checks deeper in the back-end.
1673 Note that we don't need to warn since this will be done on trying
1674 to declare the object. */
1675 if (TREE_CODE (DECL_FIELD_OFFSET (field)) == INTEGER_CST
1676 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field)))
1679 /* Look through conversion between type variants. Note that this
1680 is transparent as far as the field is concerned. */
1681 if (TREE_CODE (record_variable) == VIEW_CONVERT_EXPR
1682 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (record_variable, 0)))
1684 inner_variable = TREE_OPERAND (record_variable, 0);
1686 inner_variable = record_variable;
1688 ref = build3 (COMPONENT_REF, TREE_TYPE (field), inner_variable, field,
1691 if (TREE_READONLY (record_variable) || TREE_READONLY (field))
1692 TREE_READONLY (ref) = 1;
1693 if (TREE_THIS_VOLATILE (record_variable) || TREE_THIS_VOLATILE (field)
1694 || TYPE_VOLATILE (record_type))
1695 TREE_THIS_VOLATILE (ref) = 1;
1700 /* The generic folder may punt in this case because the inner array type
1701 can be self-referential, but folding is in fact not problematic. */
1702 else if (TREE_CODE (record_variable) == CONSTRUCTOR
1703 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (record_variable)))
1705 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (record_variable);
1706 unsigned HOST_WIDE_INT idx;
1708 FOR_EACH_CONSTRUCTOR_ELT (elts, idx, index, value)
1718 /* Like build_simple_component_ref, except that we give an error if the
1719 reference could not be found. */
1722 build_component_ref (tree record_variable, tree component,
1723 tree field, bool no_fold_p)
1725 tree ref = build_simple_component_ref (record_variable, component, field,
1731 /* If FIELD was specified, assume this is an invalid user field so raise
1732 Constraint_Error. Otherwise, we have no type to return so abort. */
1734 return build1 (NULL_EXPR, TREE_TYPE (field),
1735 build_call_raise (CE_Discriminant_Check_Failed, Empty,
1736 N_Raise_Constraint_Error));
1739 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
1740 identically. Process the case where a GNAT_PROC to call is provided. */
1743 build_call_alloc_dealloc_proc (tree gnu_obj, tree gnu_size, tree gnu_type,
1744 Entity_Id gnat_proc, Entity_Id gnat_pool)
1746 tree gnu_proc = gnat_to_gnu (gnat_proc);
1747 tree gnu_proc_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_proc);
1750 /* The storage pools are obviously always tagged types, but the
1751 secondary stack uses the same mechanism and is not tagged. */
1752 if (Is_Tagged_Type (Etype (gnat_pool)))
1754 /* The size is the third parameter; the alignment is the
1756 Entity_Id gnat_size_type
1757 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc))));
1758 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1760 tree gnu_pool = gnat_to_gnu (gnat_pool);
1761 tree gnu_pool_addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_pool);
1762 tree gnu_align = size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT);
1764 gnu_size = convert (gnu_size_type, gnu_size);
1765 gnu_align = convert (gnu_size_type, gnu_align);
1767 /* The first arg is always the address of the storage pool; next
1768 comes the address of the object, for a deallocator, then the
1769 size and alignment. */
1771 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1772 gnu_proc_addr, 4, gnu_pool_addr,
1773 gnu_obj, gnu_size, gnu_align);
1775 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1776 gnu_proc_addr, 3, gnu_pool_addr,
1777 gnu_size, gnu_align);
1780 /* Secondary stack case. */
1783 /* The size is the second parameter. */
1784 Entity_Id gnat_size_type
1785 = Etype (Next_Formal (First_Formal (gnat_proc)));
1786 tree gnu_size_type = gnat_to_gnu_type (gnat_size_type);
1788 gnu_size = convert (gnu_size_type, gnu_size);
1790 /* The first arg is the address of the object, for a deallocator,
1793 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1794 gnu_proc_addr, 2, gnu_obj, gnu_size);
1796 gnu_call = build_call_nary (TREE_TYPE (TREE_TYPE (gnu_proc)),
1797 gnu_proc_addr, 1, gnu_size);
1800 TREE_SIDE_EFFECTS (gnu_call) = 1;
1804 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
1805 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
1806 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
1810 maybe_wrap_malloc (tree data_size, tree data_type, Node_Id gnat_node)
1812 /* When the DATA_TYPE alignment is stricter than what malloc offers
1813 (super-aligned case), we allocate an "aligning" wrapper type and return
1814 the address of its single data field with the malloc's return value
1815 stored just in front. */
1817 unsigned int data_align = TYPE_ALIGN (data_type);
1818 unsigned int default_allocator_alignment
1819 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1822 = ((data_align > default_allocator_alignment)
1823 ? make_aligning_type (data_type, data_align, data_size,
1824 default_allocator_alignment,
1825 POINTER_SIZE / BITS_PER_UNIT)
1829 = aligning_type ? TYPE_SIZE_UNIT (aligning_type) : data_size;
1833 /* On VMS, if 64-bit memory is disabled or pointers are 64-bit and the
1834 allocator size is 32-bit or Convention C, allocate 32-bit memory. */
1835 if (TARGET_ABI_OPEN_VMS
1836 && (!TARGET_MALLOC64
1837 || (POINTER_SIZE == 64
1838 && (UI_To_Int (Esize (Etype (gnat_node))) == 32
1839 || Convention (Etype (gnat_node)) == Convention_C))))
1840 malloc_ptr = build_call_1_expr (malloc32_decl, size_to_malloc);
1842 malloc_ptr = build_call_1_expr (malloc_decl, size_to_malloc);
1846 /* Latch malloc's return value and get a pointer to the aligning field
1848 tree storage_ptr = gnat_protect_expr (malloc_ptr);
1850 tree aligning_record_addr
1851 = convert (build_pointer_type (aligning_type), storage_ptr);
1853 tree aligning_record
1854 = build_unary_op (INDIRECT_REF, NULL_TREE, aligning_record_addr);
1857 = build_component_ref (aligning_record, NULL_TREE,
1858 TYPE_FIELDS (aligning_type), false);
1860 tree aligning_field_addr
1861 = build_unary_op (ADDR_EXPR, NULL_TREE, aligning_field);
1863 /* Then arrange to store the allocator's return value ahead
1865 tree storage_ptr_slot_addr
1866 = build_binary_op (POINTER_PLUS_EXPR, ptr_void_type_node,
1867 convert (ptr_void_type_node, aligning_field_addr),
1868 size_int (-(HOST_WIDE_INT) POINTER_SIZE
1871 tree storage_ptr_slot
1872 = build_unary_op (INDIRECT_REF, NULL_TREE,
1873 convert (build_pointer_type (ptr_void_type_node),
1874 storage_ptr_slot_addr));
1877 build2 (COMPOUND_EXPR, TREE_TYPE (aligning_field_addr),
1878 build_binary_op (MODIFY_EXPR, NULL_TREE,
1879 storage_ptr_slot, storage_ptr),
1880 aligning_field_addr);
1886 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
1887 designated by DATA_PTR using the __gnat_free entry point. */
1890 maybe_wrap_free (tree data_ptr, tree data_type)
1892 /* In the regular alignment case, we pass the data pointer straight to free.
1893 In the superaligned case, we need to retrieve the initial allocator
1894 return value, stored in front of the data block at allocation time. */
1896 unsigned int data_align = TYPE_ALIGN (data_type);
1897 unsigned int default_allocator_alignment
1898 = get_target_default_allocator_alignment () * BITS_PER_UNIT;
1902 if (data_align > default_allocator_alignment)
1904 /* DATA_FRONT_PTR (void *)
1905 = (void *)DATA_PTR - (void *)sizeof (void *)) */
1908 (POINTER_PLUS_EXPR, ptr_void_type_node,
1909 convert (ptr_void_type_node, data_ptr),
1910 size_int (-(HOST_WIDE_INT) POINTER_SIZE / BITS_PER_UNIT));
1912 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
1915 (INDIRECT_REF, NULL_TREE,
1916 convert (build_pointer_type (ptr_void_type_node), data_front_ptr));
1919 free_ptr = data_ptr;
1921 return build_call_1_expr (free_decl, free_ptr);
1924 /* Build a GCC tree to call an allocation or deallocation function.
1925 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
1926 generate an allocator.
1928 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
1929 object type, used to determine the to-be-honored address alignment.
1930 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
1931 pool to use. If not present, malloc and free are used. GNAT_NODE is used
1932 to provide an error location for restriction violation messages. */
1935 build_call_alloc_dealloc (tree gnu_obj, tree gnu_size, tree gnu_type,
1936 Entity_Id gnat_proc, Entity_Id gnat_pool,
1939 gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_obj);
1941 /* Explicit proc to call ? This one is assumed to deal with the type
1942 alignment constraints. */
1943 if (Present (gnat_proc))
1944 return build_call_alloc_dealloc_proc (gnu_obj, gnu_size, gnu_type,
1945 gnat_proc, gnat_pool);
1947 /* Otherwise, object to "free" or "malloc" with possible special processing
1948 for alignments stricter than what the default allocator honors. */
1950 return maybe_wrap_free (gnu_obj, gnu_type);
1953 /* Assert that we no longer can be called with this special pool. */
1954 gcc_assert (gnat_pool != -1);
1956 /* Check that we aren't violating the associated restriction. */
1957 if (!(Nkind (gnat_node) == N_Allocator && Comes_From_Source (gnat_node)))
1958 Check_No_Implicit_Heap_Alloc (gnat_node);
1960 return maybe_wrap_malloc (gnu_size, gnu_type, gnat_node);
1964 /* Build a GCC tree to correspond to allocating an object of TYPE whose
1965 initial value is INIT, if INIT is nonzero. Convert the expression to
1966 RESULT_TYPE, which must be some type of pointer. Return the tree.
1968 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
1969 the storage pool to use. GNAT_NODE is used to provide an error
1970 location for restriction violation messages. If IGNORE_INIT_TYPE is
1971 true, ignore the type of INIT for the purpose of determining the size;
1972 this will cause the maximum size to be allocated if TYPE is of
1973 self-referential size. */
1976 build_allocator (tree type, tree init, tree result_type, Entity_Id gnat_proc,
1977 Entity_Id gnat_pool, Node_Id gnat_node, bool ignore_init_type)
1979 tree size = TYPE_SIZE_UNIT (type);
1982 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
1983 if (init && TREE_CODE (init) == NULL_EXPR)
1984 return build1 (NULL_EXPR, result_type, TREE_OPERAND (init, 0));
1986 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
1987 sizes of the object and its template. Allocate the whole thing and
1988 fill in the parts that are known. */
1989 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type))
1992 = build_unc_object_type_from_ptr (result_type, type,
1993 get_identifier ("ALLOC"));
1994 tree template_type = TREE_TYPE (TYPE_FIELDS (storage_type));
1995 tree storage_ptr_type = build_pointer_type (storage_type);
1997 tree template_cons = NULL_TREE;
1999 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type),
2002 /* If the size overflows, pass -1 so the allocator will raise
2004 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2005 size = ssize_int (-1);
2007 storage = build_call_alloc_dealloc (NULL_TREE, size, storage_type,
2008 gnat_proc, gnat_pool, gnat_node);
2009 storage = convert (storage_ptr_type, gnat_protect_expr (storage));
2011 if (TYPE_IS_PADDING_P (type))
2013 type = TREE_TYPE (TYPE_FIELDS (type));
2015 init = convert (type, init);
2018 /* If there is an initializing expression, make a constructor for
2019 the entire object including the bounds and copy it into the
2020 object. If there is no initializing expression, just set the
2024 template_cons = tree_cons (TREE_CHAIN (TYPE_FIELDS (storage_type)),
2026 template_cons = tree_cons (TYPE_FIELDS (storage_type),
2027 build_template (template_type, type,
2033 build2 (COMPOUND_EXPR, storage_ptr_type,
2035 (MODIFY_EXPR, storage_type,
2036 build_unary_op (INDIRECT_REF, NULL_TREE,
2037 convert (storage_ptr_type, storage)),
2038 gnat_build_constructor (storage_type, template_cons)),
2039 convert (storage_ptr_type, storage)));
2043 (COMPOUND_EXPR, result_type,
2045 (MODIFY_EXPR, template_type,
2047 (build_unary_op (INDIRECT_REF, NULL_TREE,
2048 convert (storage_ptr_type, storage)),
2049 NULL_TREE, TYPE_FIELDS (storage_type), false),
2050 build_template (template_type, type, NULL_TREE)),
2051 convert (result_type, convert (storage_ptr_type, storage)));
2054 /* If we have an initializing expression, see if its size is simpler
2055 than the size from the type. */
2056 if (!ignore_init_type && init && TYPE_SIZE_UNIT (TREE_TYPE (init))
2057 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init))) == INTEGER_CST
2058 || CONTAINS_PLACEHOLDER_P (size)))
2059 size = TYPE_SIZE_UNIT (TREE_TYPE (init));
2061 /* If the size is still self-referential, reference the initializing
2062 expression, if it is present. If not, this must have been a
2063 call to allocate a library-level object, in which case we use
2064 the maximum size. */
2065 if (CONTAINS_PLACEHOLDER_P (size))
2067 if (!ignore_init_type && init)
2068 size = substitute_placeholder_in_expr (size, init);
2070 size = max_size (size, true);
2073 /* If the size overflows, pass -1 so the allocator will raise
2075 if (TREE_CODE (size) == INTEGER_CST && TREE_OVERFLOW (size))
2076 size = ssize_int (-1);
2078 result = convert (result_type,
2079 build_call_alloc_dealloc (NULL_TREE, size, type,
2080 gnat_proc, gnat_pool,
2083 /* If we have an initial value, protect the new address, assign the value
2084 and return the address with a COMPOUND_EXPR. */
2087 result = gnat_protect_expr (result);
2089 = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2091 (MODIFY_EXPR, NULL_TREE,
2092 build_unary_op (INDIRECT_REF,
2093 TREE_TYPE (TREE_TYPE (result)), result),
2098 return convert (result_type, result);
2101 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
2102 GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is
2103 how we derive the source location to raise C_E on an out of range
2107 fill_vms_descriptor (tree expr, Entity_Id gnat_formal, Node_Id gnat_actual)
2109 tree parm_decl = get_gnu_tree (gnat_formal);
2110 tree record_type = TREE_TYPE (TREE_TYPE (parm_decl));
2111 tree const_list = NULL_TREE, field;
2112 const bool do_range_check
2114 IDENTIFIER_POINTER (DECL_NAME (TYPE_FIELDS (record_type))));
2116 expr = maybe_unconstrained_array (expr);
2117 gnat_mark_addressable (expr);
2119 for (field = TYPE_FIELDS (record_type); field; field = TREE_CHAIN (field))
2121 tree conexpr = convert (TREE_TYPE (field),
2122 SUBSTITUTE_PLACEHOLDER_IN_EXPR
2123 (DECL_INITIAL (field), expr));
2125 /* Check to ensure that only 32-bit pointers are passed in
2126 32-bit descriptors */
2128 && strcmp (IDENTIFIER_POINTER (DECL_NAME (field)), "POINTER") == 0)
2131 = build_pointer_type_for_mode (void_type_node, DImode, false);
2132 tree addr64expr = build_unary_op (ADDR_EXPR, pointer64type, expr);
2134 = build_int_cstu (long_integer_type_node, 0x80000000);
2136 add_stmt (build3 (COND_EXPR, void_type_node,
2137 build_binary_op (GE_EXPR, boolean_type_node,
2138 convert (long_integer_type_node,
2141 build_call_raise (CE_Range_Check_Failed,
2143 N_Raise_Constraint_Error),
2146 const_list = tree_cons (field, conexpr, const_list);
2149 return gnat_build_constructor (record_type, nreverse (const_list));
2152 /* Indicate that we need to take the address of T and that it therefore
2153 should not be allocated in a register. Returns true if successful. */
2156 gnat_mark_addressable (tree t)
2159 switch (TREE_CODE (t))
2164 case ARRAY_RANGE_REF:
2167 case VIEW_CONVERT_EXPR:
2168 case NON_LVALUE_EXPR:
2170 t = TREE_OPERAND (t, 0);
2174 t = TREE_OPERAND (t, 1);
2178 TREE_ADDRESSABLE (t) = 1;
2184 TREE_ADDRESSABLE (t) = 1;
2188 TREE_ADDRESSABLE (t) = 1;
2192 return DECL_CONST_CORRESPONDING_VAR (t)
2193 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t));
2200 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2201 but we know how to handle our own nodes. */
2204 gnat_save_expr (tree exp)
2206 tree type = TREE_TYPE (exp);
2207 enum tree_code code = TREE_CODE (exp);
2209 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2212 if (code == UNCONSTRAINED_ARRAY_REF)
2214 tree t = build1 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)));
2215 TREE_READONLY (t) = TYPE_READONLY (type);
2219 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2220 This may be more efficient, but will also allow us to more easily find
2221 the match for the PLACEHOLDER_EXPR. */
2222 if (code == COMPONENT_REF
2223 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2224 return build3 (code, type, gnat_save_expr (TREE_OPERAND (exp, 0)),
2225 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2227 return save_expr (exp);
2230 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2231 is optimized under the assumption that EXP's value doesn't change before
2232 its subsequent reuse(s) except through its potential reevaluation. */
2235 gnat_protect_expr (tree exp)
2237 tree type = TREE_TYPE (exp);
2238 enum tree_code code = TREE_CODE (exp);
2240 if (TREE_CONSTANT (exp) || code == SAVE_EXPR || code == NULL_EXPR)
2243 /* If EXP has no side effects, we theoritically don't need to do anything.
2244 However, we may be recursively passed more and more complex expressions
2245 involving checks which will be reused multiple times and eventually be
2246 unshared for gimplification; in order to avoid a complexity explosion
2247 at that point, we protect any expressions more complex than a simple
2248 arithmetic expression. */
2249 if (!TREE_SIDE_EFFECTS (exp))
2251 tree inner = skip_simple_arithmetic (exp);
2252 if (!EXPR_P (inner) || REFERENCE_CLASS_P (inner))
2256 /* If this is a conversion, protect what's inside the conversion. */
2257 if (code == NON_LVALUE_EXPR
2258 || CONVERT_EXPR_CODE_P (code)
2259 || code == VIEW_CONVERT_EXPR)
2260 return build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2262 /* If we're indirectly referencing something, we only need to protect the
2263 address since the data itself can't change in these situations. */
2264 if (code == INDIRECT_REF || code == UNCONSTRAINED_ARRAY_REF)
2266 tree t = build1 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)));
2267 TREE_READONLY (t) = TYPE_READONLY (type);
2271 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2272 This may be more efficient, but will also allow us to more easily find
2273 the match for the PLACEHOLDER_EXPR. */
2274 if (code == COMPONENT_REF
2275 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
2276 return build3 (code, type, gnat_protect_expr (TREE_OPERAND (exp, 0)),
2277 TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2));
2279 /* If this is a fat pointer or something that can be placed in a register,
2280 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2281 returned via invisible reference in most ABIs so the temporary will
2282 directly be filled by the callee. */
2283 if (TYPE_IS_FAT_POINTER_P (type)
2284 || TYPE_MODE (type) != BLKmode
2285 || code == CALL_EXPR)
2286 return save_expr (exp);
2288 /* Otherwise reference, protect the address and dereference. */
2290 build_unary_op (INDIRECT_REF, type,
2291 save_expr (build_unary_op (ADDR_EXPR,
2292 build_reference_type (type),
2296 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2297 argument to force evaluation of everything. */
2300 gnat_stabilize_reference_1 (tree e, bool force)
2302 enum tree_code code = TREE_CODE (e);
2303 tree type = TREE_TYPE (e);
2306 /* We cannot ignore const expressions because it might be a reference
2307 to a const array but whose index contains side-effects. But we can
2308 ignore things that are actual constant or that already have been
2309 handled by this function. */
2310 if (TREE_CONSTANT (e) || code == SAVE_EXPR)
2313 switch (TREE_CODE_CLASS (code))
2315 case tcc_exceptional:
2316 case tcc_declaration:
2317 case tcc_comparison:
2318 case tcc_expression:
2321 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2322 fat pointer. This may be more efficient, but will also allow
2323 us to more easily find the match for the PLACEHOLDER_EXPR. */
2324 if (code == COMPONENT_REF
2325 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e, 0))))
2327 = build3 (code, type,
2328 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2329 TREE_OPERAND (e, 1), TREE_OPERAND (e, 2));
2330 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2331 so that it will only be evaluated once. */
2332 /* The tcc_reference and tcc_comparison classes could be handled as
2333 below, but it is generally faster to only evaluate them once. */
2334 else if (TREE_SIDE_EFFECTS (e) || force)
2335 return save_expr (e);
2341 /* Recursively stabilize each operand. */
2343 = build2 (code, type,
2344 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force),
2345 gnat_stabilize_reference_1 (TREE_OPERAND (e, 1), force));
2349 /* Recursively stabilize each operand. */
2351 = build1 (code, type,
2352 gnat_stabilize_reference_1 (TREE_OPERAND (e, 0), force));
2359 /* See similar handling in gnat_stabilize_reference. */
2360 TREE_READONLY (result) = TREE_READONLY (e);
2361 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (e);
2362 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
2367 /* This is equivalent to stabilize_reference in tree.c but we know how to
2368 handle our own nodes and we take extra arguments. FORCE says whether to
2369 force evaluation of everything. We set SUCCESS to true unless we walk
2370 through something we don't know how to stabilize. */
2373 gnat_stabilize_reference (tree ref, bool force, bool *success)
2375 tree type = TREE_TYPE (ref);
2376 enum tree_code code = TREE_CODE (ref);
2379 /* Assume we'll success unless proven otherwise. */
2389 /* No action is needed in this case. */
2395 case FIX_TRUNC_EXPR:
2396 case VIEW_CONVERT_EXPR:
2398 = build1 (code, type,
2399 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2404 case UNCONSTRAINED_ARRAY_REF:
2405 result = build1 (code, type,
2406 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 0),
2411 result = build3 (COMPONENT_REF, type,
2412 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2414 TREE_OPERAND (ref, 1), NULL_TREE);
2418 result = build3 (BIT_FIELD_REF, type,
2419 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2421 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2423 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 2),
2428 case ARRAY_RANGE_REF:
2429 result = build4 (code, type,
2430 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2432 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2434 NULL_TREE, NULL_TREE);
2438 result = gnat_stabilize_reference_1 (ref, force);
2442 result = build2 (COMPOUND_EXPR, type,
2443 gnat_stabilize_reference (TREE_OPERAND (ref, 0), force,
2445 gnat_stabilize_reference_1 (TREE_OPERAND (ref, 1),
2450 /* Constructors with 1 element are used extensively to formally
2451 convert objects to special wrapping types. */
2452 if (TREE_CODE (type) == RECORD_TYPE
2453 && VEC_length (constructor_elt, CONSTRUCTOR_ELTS (ref)) == 1)
2456 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->index;
2458 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ref), 0)->value;
2460 = build_constructor_single (type, index,
2461 gnat_stabilize_reference_1 (value,
2473 ref = error_mark_node;
2475 /* ... fall through to failure ... */
2477 /* If arg isn't a kind of lvalue we recognize, make no change.
2478 Caller should recognize the error for an invalid lvalue. */
2485 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2486 may not be sustained across some paths, such as the way via build1 for
2487 INDIRECT_REF. We reset those flags here in the general case, which is
2488 consistent with the GCC version of this routine.
2490 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2491 paths introduce side-effects where there was none initially (e.g. if a
2492 SAVE_EXPR is built) and we also want to keep track of that. */
2493 TREE_READONLY (result) = TREE_READONLY (ref);
2494 TREE_SIDE_EFFECTS (result) |= TREE_SIDE_EFFECTS (ref);
2495 TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);