1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2014, 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"
33 #include "double-int.h"
40 #include "fold-const.h"
41 #include "stor-layout.h"
42 #include "stringpool.h"
47 #include "tree-inline.h"
64 /* Return the base type of TYPE. */
67 get_base_type (tree type
)
69 if (TREE_CODE (type
) == RECORD_TYPE
70 && TYPE_JUSTIFIED_MODULAR_P (type
))
71 type
= TREE_TYPE (TYPE_FIELDS (type
));
73 while (TREE_TYPE (type
)
74 && (TREE_CODE (type
) == INTEGER_TYPE
75 || TREE_CODE (type
) == REAL_TYPE
))
76 type
= TREE_TYPE (type
);
81 /* EXP is a GCC tree representing an address. See if we can find how
82 strictly the object at that address is aligned. Return that alignment
83 in bits. If we don't know anything about the alignment, return 0. */
86 known_alignment (tree exp
)
88 unsigned int this_alignment
;
89 unsigned int lhs
, rhs
;
91 switch (TREE_CODE (exp
))
94 case VIEW_CONVERT_EXPR
:
96 /* Conversions between pointers and integers don't change the alignment
97 of the underlying object. */
98 this_alignment
= known_alignment (TREE_OPERAND (exp
, 0));
102 /* The value of a COMPOUND_EXPR is that of it's second operand. */
103 this_alignment
= known_alignment (TREE_OPERAND (exp
, 1));
108 /* If two address are added, the alignment of the result is the
109 minimum of the two alignments. */
110 lhs
= known_alignment (TREE_OPERAND (exp
, 0));
111 rhs
= known_alignment (TREE_OPERAND (exp
, 1));
112 this_alignment
= MIN (lhs
, rhs
);
115 case POINTER_PLUS_EXPR
:
116 lhs
= known_alignment (TREE_OPERAND (exp
, 0));
117 rhs
= known_alignment (TREE_OPERAND (exp
, 1));
118 /* If we don't know the alignment of the offset, we assume that
121 this_alignment
= lhs
;
123 this_alignment
= MIN (lhs
, rhs
);
127 /* If there is a choice between two values, use the smallest one. */
128 lhs
= known_alignment (TREE_OPERAND (exp
, 1));
129 rhs
= known_alignment (TREE_OPERAND (exp
, 2));
130 this_alignment
= MIN (lhs
, rhs
);
135 unsigned HOST_WIDE_INT c
= TREE_INT_CST_LOW (exp
);
136 /* The first part of this represents the lowest bit in the constant,
137 but it is originally in bytes, not bits. */
138 this_alignment
= MIN (BITS_PER_UNIT
* (c
& -c
), BIGGEST_ALIGNMENT
);
143 /* If we know the alignment of just one side, use it. Otherwise,
144 use the product of the alignments. */
145 lhs
= known_alignment (TREE_OPERAND (exp
, 0));
146 rhs
= known_alignment (TREE_OPERAND (exp
, 1));
149 this_alignment
= rhs
;
151 this_alignment
= lhs
;
153 this_alignment
= MIN (lhs
* rhs
, BIGGEST_ALIGNMENT
);
157 /* A bit-and expression is as aligned as the maximum alignment of the
158 operands. We typically get here for a complex lhs and a constant
159 negative power of two on the rhs to force an explicit alignment, so
160 don't bother looking at the lhs. */
161 this_alignment
= known_alignment (TREE_OPERAND (exp
, 1));
165 this_alignment
= expr_align (TREE_OPERAND (exp
, 0));
170 tree t
= maybe_inline_call_in_expr (exp
);
172 return known_alignment (t
);
175 /* Fall through... */
178 /* For other pointer expressions, we assume that the pointed-to object
179 is at least as aligned as the pointed-to type. Beware that we can
180 have a dummy type here (e.g. a Taft Amendment type), for which the
181 alignment is meaningless and should be ignored. */
182 if (POINTER_TYPE_P (TREE_TYPE (exp
))
183 && !TYPE_IS_DUMMY_P (TREE_TYPE (TREE_TYPE (exp
))))
184 this_alignment
= TYPE_ALIGN (TREE_TYPE (TREE_TYPE (exp
)));
190 return this_alignment
;
193 /* We have a comparison or assignment operation on two types, T1 and T2, which
194 are either both array types or both record types. T1 is assumed to be for
195 the left hand side operand, and T2 for the right hand side. Return the
196 type that both operands should be converted to for the operation, if any.
197 Otherwise return zero. */
200 find_common_type (tree t1
, tree t2
)
202 /* ??? As of today, various constructs lead to here with types of different
203 sizes even when both constants (e.g. tagged types, packable vs regular
204 component types, padded vs unpadded types, ...). While some of these
205 would better be handled upstream (types should be made consistent before
206 calling into build_binary_op), some others are really expected and we
207 have to be careful. */
209 /* We must avoid writing more than what the target can hold if this is for
210 an assignment and the case of tagged types is handled in build_binary_op
211 so we use the lhs type if it is known to be smaller or of constant size
212 and the rhs type is not, whatever the modes. We also force t1 in case of
213 constant size equality to minimize occurrences of view conversions on the
214 lhs of an assignment, except for the case of record types with a variant
215 part on the lhs but not on the rhs to make the conversion simpler. */
216 if (TREE_CONSTANT (TYPE_SIZE (t1
))
217 && (!TREE_CONSTANT (TYPE_SIZE (t2
))
218 || tree_int_cst_lt (TYPE_SIZE (t1
), TYPE_SIZE (t2
))
219 || (TYPE_SIZE (t1
) == TYPE_SIZE (t2
)
220 && !(TREE_CODE (t1
) == RECORD_TYPE
221 && TREE_CODE (t2
) == RECORD_TYPE
222 && get_variant_part (t1
) != NULL_TREE
223 && get_variant_part (t2
) == NULL_TREE
))))
226 /* Otherwise, if the lhs type is non-BLKmode, use it. Note that we know
227 that we will not have any alignment problems since, if we did, the
228 non-BLKmode type could not have been used. */
229 if (TYPE_MODE (t1
) != BLKmode
)
232 /* If the rhs type is of constant size, use it whatever the modes. At
233 this point it is known to be smaller, or of constant size and the
235 if (TREE_CONSTANT (TYPE_SIZE (t2
)))
238 /* Otherwise, if the rhs type is non-BLKmode, use it. */
239 if (TYPE_MODE (t2
) != BLKmode
)
242 /* In this case, both types have variable size and BLKmode. It's
243 probably best to leave the "type mismatch" because changing it
244 could cause a bad self-referential reference. */
248 /* Return an expression tree representing an equality comparison of A1 and A2,
249 two objects of type ARRAY_TYPE. The result should be of type RESULT_TYPE.
251 Two arrays are equal in one of two ways: (1) if both have zero length in
252 some dimension (not necessarily the same dimension) or (2) if the lengths
253 in each dimension are equal and the data is equal. We perform the length
254 tests in as efficient a manner as possible. */
257 compare_arrays (location_t loc
, tree result_type
, tree a1
, tree a2
)
259 tree result
= convert (result_type
, boolean_true_node
);
260 tree a1_is_null
= convert (result_type
, boolean_false_node
);
261 tree a2_is_null
= convert (result_type
, boolean_false_node
);
262 tree t1
= TREE_TYPE (a1
);
263 tree t2
= TREE_TYPE (a2
);
264 bool a1_side_effects_p
= TREE_SIDE_EFFECTS (a1
);
265 bool a2_side_effects_p
= TREE_SIDE_EFFECTS (a2
);
266 bool length_zero_p
= false;
268 /* If the operands have side-effects, they need to be evaluated only once
269 in spite of the multiple references in the comparison. */
270 if (a1_side_effects_p
)
271 a1
= gnat_protect_expr (a1
);
273 if (a2_side_effects_p
)
274 a2
= gnat_protect_expr (a2
);
276 /* Process each dimension separately and compare the lengths. If any
277 dimension has a length known to be zero, set LENGTH_ZERO_P to true
278 in order to suppress the comparison of the data at the end. */
279 while (TREE_CODE (t1
) == ARRAY_TYPE
&& TREE_CODE (t2
) == ARRAY_TYPE
)
281 tree lb1
= TYPE_MIN_VALUE (TYPE_DOMAIN (t1
));
282 tree ub1
= TYPE_MAX_VALUE (TYPE_DOMAIN (t1
));
283 tree lb2
= TYPE_MIN_VALUE (TYPE_DOMAIN (t2
));
284 tree ub2
= TYPE_MAX_VALUE (TYPE_DOMAIN (t2
));
285 tree length1
= size_binop (PLUS_EXPR
, size_binop (MINUS_EXPR
, ub1
, lb1
),
287 tree length2
= size_binop (PLUS_EXPR
, size_binop (MINUS_EXPR
, ub2
, lb2
),
289 tree comparison
, this_a1_is_null
, this_a2_is_null
;
291 /* If the length of the first array is a constant, swap our operands
292 unless the length of the second array is the constant zero. */
293 if (TREE_CODE (length1
) == INTEGER_CST
&& !integer_zerop (length2
))
298 tem
= a1
, a1
= a2
, a2
= tem
;
299 tem
= t1
, t1
= t2
, t2
= tem
;
300 tem
= lb1
, lb1
= lb2
, lb2
= tem
;
301 tem
= ub1
, ub1
= ub2
, ub2
= tem
;
302 tem
= length1
, length1
= length2
, length2
= tem
;
303 tem
= a1_is_null
, a1_is_null
= a2_is_null
, a2_is_null
= tem
;
304 btem
= a1_side_effects_p
, a1_side_effects_p
= a2_side_effects_p
,
305 a2_side_effects_p
= btem
;
308 /* If the length of the second array is the constant zero, we can just
309 use the original stored bounds for the first array and see whether
310 last < first holds. */
311 if (integer_zerop (length2
))
313 tree b
= get_base_type (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
)));
315 length_zero_p
= true;
318 = convert (b
, TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
))));
320 = convert (b
, TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
))));
322 comparison
= fold_build2_loc (loc
, LT_EXPR
, result_type
, ub1
, lb1
);
323 comparison
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison
, a1
);
324 if (EXPR_P (comparison
))
325 SET_EXPR_LOCATION (comparison
, loc
);
327 this_a1_is_null
= comparison
;
328 this_a2_is_null
= convert (result_type
, boolean_true_node
);
331 /* Otherwise, if the length is some other constant value, we know that
332 this dimension in the second array cannot be superflat, so we can
333 just use its length computed from the actual stored bounds. */
334 else if (TREE_CODE (length2
) == INTEGER_CST
)
336 tree b
= get_base_type (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
)));
339 = convert (b
, TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
))));
341 = convert (b
, TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t1
))));
342 /* Note that we know that UB2 and LB2 are constant and hence
343 cannot contain a PLACEHOLDER_EXPR. */
345 = convert (b
, TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2
))));
347 = convert (b
, TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (t2
))));
350 = fold_build2_loc (loc
, EQ_EXPR
, result_type
,
351 build_binary_op (MINUS_EXPR
, b
, ub1
, lb1
),
352 build_binary_op (MINUS_EXPR
, b
, ub2
, lb2
));
353 comparison
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (comparison
, a1
);
354 if (EXPR_P (comparison
))
355 SET_EXPR_LOCATION (comparison
, loc
);
358 = fold_build2_loc (loc
, LT_EXPR
, result_type
, ub1
, lb1
);
360 this_a2_is_null
= convert (result_type
, boolean_false_node
);
363 /* Otherwise, compare the computed lengths. */
366 length1
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (length1
, a1
);
367 length2
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (length2
, a2
);
370 = fold_build2_loc (loc
, EQ_EXPR
, result_type
, length1
, length2
);
372 /* If the length expression is of the form (cond ? val : 0), assume
373 that cond is equivalent to (length != 0). That's guaranteed by
374 construction of the array types in gnat_to_gnu_entity. */
375 if (TREE_CODE (length1
) == COND_EXPR
376 && integer_zerop (TREE_OPERAND (length1
, 2)))
378 = invert_truthvalue_loc (loc
, TREE_OPERAND (length1
, 0));
380 this_a1_is_null
= fold_build2_loc (loc
, EQ_EXPR
, result_type
,
381 length1
, size_zero_node
);
383 /* Likewise for the second array. */
384 if (TREE_CODE (length2
) == COND_EXPR
385 && integer_zerop (TREE_OPERAND (length2
, 2)))
387 = invert_truthvalue_loc (loc
, TREE_OPERAND (length2
, 0));
389 this_a2_is_null
= fold_build2_loc (loc
, EQ_EXPR
, result_type
,
390 length2
, size_zero_node
);
393 /* Append expressions for this dimension to the final expressions. */
394 result
= build_binary_op (TRUTH_ANDIF_EXPR
, result_type
,
397 a1_is_null
= build_binary_op (TRUTH_ORIF_EXPR
, result_type
,
398 this_a1_is_null
, a1_is_null
);
400 a2_is_null
= build_binary_op (TRUTH_ORIF_EXPR
, result_type
,
401 this_a2_is_null
, a2_is_null
);
407 /* Unless the length of some dimension is known to be zero, compare the
408 data in the array. */
411 tree type
= find_common_type (TREE_TYPE (a1
), TREE_TYPE (a2
));
416 a1
= convert (type
, a1
),
417 a2
= convert (type
, a2
);
420 comparison
= fold_build2_loc (loc
, EQ_EXPR
, result_type
, a1
, a2
);
423 = build_binary_op (TRUTH_ANDIF_EXPR
, result_type
, result
, comparison
);
426 /* The result is also true if both sizes are zero. */
427 result
= build_binary_op (TRUTH_ORIF_EXPR
, result_type
,
428 build_binary_op (TRUTH_ANDIF_EXPR
, result_type
,
429 a1_is_null
, a2_is_null
),
432 /* If the operands have side-effects, they need to be evaluated before
433 doing the tests above since the place they otherwise would end up
434 being evaluated at run time could be wrong. */
435 if (a1_side_effects_p
)
436 result
= build2 (COMPOUND_EXPR
, result_type
, a1
, result
);
438 if (a2_side_effects_p
)
439 result
= build2 (COMPOUND_EXPR
, result_type
, a2
, result
);
444 /* Return an expression tree representing an equality comparison of P1 and P2,
445 two objects of fat pointer type. The result should be of type RESULT_TYPE.
447 Two fat pointers are equal in one of two ways: (1) if both have a null
448 pointer to the array or (2) if they contain the same couple of pointers.
449 We perform the comparison in as efficient a manner as possible. */
452 compare_fat_pointers (location_t loc
, tree result_type
, tree p1
, tree p2
)
454 tree p1_array
, p2_array
, p1_bounds
, p2_bounds
, same_array
, same_bounds
;
455 tree p1_array_is_null
, p2_array_is_null
;
457 /* If either operand has side-effects, they have to be evaluated only once
458 in spite of the multiple references to the operand in the comparison. */
459 p1
= gnat_protect_expr (p1
);
460 p2
= gnat_protect_expr (p2
);
462 /* The constant folder doesn't fold fat pointer types so we do it here. */
463 if (TREE_CODE (p1
) == CONSTRUCTOR
)
464 p1_array
= (*CONSTRUCTOR_ELTS (p1
))[0].value
;
466 p1_array
= build_component_ref (p1
, NULL_TREE
,
467 TYPE_FIELDS (TREE_TYPE (p1
)), true);
470 = fold_build2_loc (loc
, EQ_EXPR
, result_type
, p1_array
,
471 fold_convert_loc (loc
, TREE_TYPE (p1_array
),
474 if (TREE_CODE (p2
) == CONSTRUCTOR
)
475 p2_array
= (*CONSTRUCTOR_ELTS (p2
))[0].value
;
477 p2_array
= build_component_ref (p2
, NULL_TREE
,
478 TYPE_FIELDS (TREE_TYPE (p2
)), true);
481 = fold_build2_loc (loc
, EQ_EXPR
, result_type
, p2_array
,
482 fold_convert_loc (loc
, TREE_TYPE (p2_array
),
485 /* If one of the pointers to the array is null, just compare the other. */
486 if (integer_zerop (p1_array
))
487 return p2_array_is_null
;
488 else if (integer_zerop (p2_array
))
489 return p1_array_is_null
;
491 /* Otherwise, do the fully-fledged comparison. */
493 = fold_build2_loc (loc
, EQ_EXPR
, result_type
, p1_array
, p2_array
);
495 if (TREE_CODE (p1
) == CONSTRUCTOR
)
496 p1_bounds
= (*CONSTRUCTOR_ELTS (p1
))[1].value
;
499 = build_component_ref (p1
, NULL_TREE
,
500 DECL_CHAIN (TYPE_FIELDS (TREE_TYPE (p1
))), true);
502 if (TREE_CODE (p2
) == CONSTRUCTOR
)
503 p2_bounds
= (*CONSTRUCTOR_ELTS (p2
))[1].value
;
506 = build_component_ref (p2
, NULL_TREE
,
507 DECL_CHAIN (TYPE_FIELDS (TREE_TYPE (p2
))), true);
510 = fold_build2_loc (loc
, EQ_EXPR
, result_type
, p1_bounds
, p2_bounds
);
512 /* P1_ARRAY == P2_ARRAY && (P1_ARRAY == NULL || P1_BOUNDS == P2_BOUNDS). */
513 return build_binary_op (TRUTH_ANDIF_EXPR
, result_type
, same_array
,
514 build_binary_op (TRUTH_ORIF_EXPR
, result_type
,
515 p1_array_is_null
, same_bounds
));
518 /* Compute the result of applying OP_CODE to LHS and RHS, where both are of
519 type TYPE. We know that TYPE is a modular type with a nonbinary
523 nonbinary_modular_operation (enum tree_code op_code
, tree type
, tree lhs
,
526 tree modulus
= TYPE_MODULUS (type
);
527 unsigned int needed_precision
= tree_floor_log2 (modulus
) + 1;
528 unsigned int precision
;
529 bool unsignedp
= true;
533 /* If this is an addition of a constant, convert it to a subtraction
534 of a constant since we can do that faster. */
535 if (op_code
== PLUS_EXPR
&& TREE_CODE (rhs
) == INTEGER_CST
)
537 rhs
= fold_build2 (MINUS_EXPR
, type
, modulus
, rhs
);
538 op_code
= MINUS_EXPR
;
541 /* For the logical operations, we only need PRECISION bits. For
542 addition and subtraction, we need one more and for multiplication we
543 need twice as many. But we never want to make a size smaller than
545 if (op_code
== PLUS_EXPR
|| op_code
== MINUS_EXPR
)
546 needed_precision
+= 1;
547 else if (op_code
== MULT_EXPR
)
548 needed_precision
*= 2;
550 precision
= MAX (needed_precision
, TYPE_PRECISION (op_type
));
552 /* Unsigned will do for everything but subtraction. */
553 if (op_code
== MINUS_EXPR
)
556 /* If our type is the wrong signedness or isn't wide enough, make a new
557 type and convert both our operands to it. */
558 if (TYPE_PRECISION (op_type
) < precision
559 || TYPE_UNSIGNED (op_type
) != unsignedp
)
561 /* Copy the node so we ensure it can be modified to make it modular. */
562 op_type
= copy_node (gnat_type_for_size (precision
, unsignedp
));
563 modulus
= convert (op_type
, modulus
);
564 SET_TYPE_MODULUS (op_type
, modulus
);
565 TYPE_MODULAR_P (op_type
) = 1;
566 lhs
= convert (op_type
, lhs
);
567 rhs
= convert (op_type
, rhs
);
570 /* Do the operation, then we'll fix it up. */
571 result
= fold_build2 (op_code
, op_type
, lhs
, rhs
);
573 /* For multiplication, we have no choice but to do a full modulus
574 operation. However, we want to do this in the narrowest
576 if (op_code
== MULT_EXPR
)
578 tree div_type
= copy_node (gnat_type_for_size (needed_precision
, 1));
579 modulus
= convert (div_type
, modulus
);
580 SET_TYPE_MODULUS (div_type
, modulus
);
581 TYPE_MODULAR_P (div_type
) = 1;
582 result
= convert (op_type
,
583 fold_build2 (TRUNC_MOD_EXPR
, div_type
,
584 convert (div_type
, result
), modulus
));
587 /* For subtraction, add the modulus back if we are negative. */
588 else if (op_code
== MINUS_EXPR
)
590 result
= gnat_protect_expr (result
);
591 result
= fold_build3 (COND_EXPR
, op_type
,
592 fold_build2 (LT_EXPR
, boolean_type_node
, result
,
593 convert (op_type
, integer_zero_node
)),
594 fold_build2 (PLUS_EXPR
, op_type
, result
, modulus
),
598 /* For the other operations, subtract the modulus if we are >= it. */
601 result
= gnat_protect_expr (result
);
602 result
= fold_build3 (COND_EXPR
, op_type
,
603 fold_build2 (GE_EXPR
, boolean_type_node
,
605 fold_build2 (MINUS_EXPR
, op_type
,
610 return convert (type
, result
);
613 /* This page contains routines that implement the Ada semantics with regard
614 to atomic objects. They are fully piggybacked on the middle-end support
615 for atomic loads and stores.
617 *** Memory barriers and volatile objects ***
619 We implement the weakened form of the C.6(16) clause that was introduced
620 in Ada 2012 (AI05-117). Earlier forms of this clause wouldn't have been
621 implementable without significant performance hits on modern platforms.
623 We also take advantage of the requirements imposed on shared variables by
624 9.10 (conditions for sequential actions) to have non-erroneous execution
625 and consider that C.6(16) and C.6(17) only prescribe an uniform order of
626 volatile updates with regard to sequential actions, i.e. with regard to
627 reads or updates of atomic objects.
629 As such, an update of an atomic object by a task requires that all earlier
630 accesses to volatile objects have completed. Similarly, later accesses to
631 volatile objects cannot be reordered before the update of the atomic object.
632 So, memory barriers both before and after the atomic update are needed.
634 For a read of an atomic object, to avoid seeing writes of volatile objects
635 by a task earlier than by the other tasks, a memory barrier is needed before
636 the atomic read. Finally, to avoid reordering later reads or updates of
637 volatile objects to before the atomic read, a barrier is needed after the
640 So, memory barriers are needed before and after atomic reads and updates.
641 And, in order to simplify the implementation, we use full memory barriers
642 in all cases, i.e. we enforce sequential consistency for atomic accesses. */
644 /* Return the size of TYPE, which must be a positive power of 2. */
647 resolve_atomic_size (tree type
)
649 unsigned HOST_WIDE_INT size
= tree_to_uhwi (TYPE_SIZE_UNIT (type
));
651 if (size
== 1 || size
== 2 || size
== 4 || size
== 8 || size
== 16)
654 /* We shouldn't reach here without having already detected that the size
655 isn't compatible with an atomic access. */
656 gcc_assert (Serious_Errors_Detected
);
661 /* Build an atomic load for the underlying atomic object in SRC. */
664 build_atomic_load (tree src
)
668 (build_qualified_type (void_type_node
, TYPE_QUAL_VOLATILE
));
669 tree mem_model
= build_int_cst (integer_type_node
, MEMMODEL_SEQ_CST
);
675 /* Remove conversions to get the address of the underlying object. */
676 src
= remove_conversions (src
, false);
677 size
= resolve_atomic_size (TREE_TYPE (src
));
681 fncode
= (int) BUILT_IN_ATOMIC_LOAD_N
+ exact_log2 (size
) + 1;
682 t
= builtin_decl_implicit ((enum built_in_function
) fncode
);
684 addr
= build_unary_op (ADDR_EXPR
, ptr_type
, src
);
685 val
= build_call_expr (t
, 2, addr
, mem_model
);
687 /* First reinterpret the loaded bits in the original type of the load,
688 then convert to the expected result type. */
689 t
= fold_build1 (VIEW_CONVERT_EXPR
, TREE_TYPE (src
), val
);
690 return convert (TREE_TYPE (orig_src
), t
);
693 /* Build an atomic store from SRC to the underlying atomic object in DEST. */
696 build_atomic_store (tree dest
, tree src
)
700 (build_qualified_type (void_type_node
, TYPE_QUAL_VOLATILE
));
701 tree mem_model
= build_int_cst (integer_type_node
, MEMMODEL_SEQ_CST
);
702 tree orig_dest
= dest
;
703 tree t
, int_type
, addr
;
707 /* Remove conversions to get the address of the underlying object. */
708 dest
= remove_conversions (dest
, false);
709 size
= resolve_atomic_size (TREE_TYPE (dest
));
711 return build_binary_op (MODIFY_EXPR
, NULL_TREE
, orig_dest
, src
);
713 fncode
= (int) BUILT_IN_ATOMIC_STORE_N
+ exact_log2 (size
) + 1;
714 t
= builtin_decl_implicit ((enum built_in_function
) fncode
);
715 int_type
= gnat_type_for_size (BITS_PER_UNIT
* size
, 1);
717 /* First convert the bits to be stored to the original type of the store,
718 then reinterpret them in the effective type. But if the original type
719 is a padded type with the same size, convert to the inner type instead,
720 as we don't want to artificially introduce a CONSTRUCTOR here. */
721 if (TYPE_IS_PADDING_P (TREE_TYPE (dest
))
722 && TYPE_SIZE (TREE_TYPE (dest
))
723 == TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (dest
)))))
724 src
= convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (dest
))), src
);
726 src
= convert (TREE_TYPE (dest
), src
);
727 src
= fold_build1 (VIEW_CONVERT_EXPR
, int_type
, src
);
728 addr
= build_unary_op (ADDR_EXPR
, ptr_type
, dest
);
730 return build_call_expr (t
, 3, addr
, src
, mem_model
);
733 /* Make a binary operation of kind OP_CODE. RESULT_TYPE is the type
734 desired for the result. Usually the operation is to be performed
735 in that type. For INIT_EXPR and MODIFY_EXPR, RESULT_TYPE must be
736 NULL_TREE. For ARRAY_REF, RESULT_TYPE may be NULL_TREE, in which
737 case the type to be used will be derived from the operands.
739 This function is very much unlike the ones for C and C++ since we
740 have already done any type conversion and matching required. All we
741 have to do here is validate the work done by SEM and handle subtypes. */
744 build_binary_op (enum tree_code op_code
, tree result_type
,
745 tree left_operand
, tree right_operand
)
747 tree left_type
= TREE_TYPE (left_operand
);
748 tree right_type
= TREE_TYPE (right_operand
);
749 tree left_base_type
= get_base_type (left_type
);
750 tree right_base_type
= get_base_type (right_type
);
751 tree operation_type
= result_type
;
752 tree best_type
= NULL_TREE
;
753 tree modulus
, result
;
754 bool has_side_effects
= false;
757 && TREE_CODE (operation_type
) == RECORD_TYPE
758 && TYPE_JUSTIFIED_MODULAR_P (operation_type
))
759 operation_type
= TREE_TYPE (TYPE_FIELDS (operation_type
));
762 && TREE_CODE (operation_type
) == INTEGER_TYPE
763 && TYPE_EXTRA_SUBTYPE_P (operation_type
))
764 operation_type
= get_base_type (operation_type
);
766 modulus
= (operation_type
767 && TREE_CODE (operation_type
) == INTEGER_TYPE
768 && TYPE_MODULAR_P (operation_type
)
769 ? TYPE_MODULUS (operation_type
) : NULL_TREE
);
775 #ifdef ENABLE_CHECKING
776 gcc_assert (result_type
== NULL_TREE
);
778 /* If there were integral or pointer conversions on the LHS, remove
779 them; we'll be putting them back below if needed. Likewise for
780 conversions between array and record types, except for justified
781 modular types. But don't do this if the right operand is not
782 BLKmode (for packed arrays) unless we are not changing the mode. */
783 while ((CONVERT_EXPR_P (left_operand
)
784 || TREE_CODE (left_operand
) == VIEW_CONVERT_EXPR
)
785 && (((INTEGRAL_TYPE_P (left_type
)
786 || POINTER_TYPE_P (left_type
))
787 && (INTEGRAL_TYPE_P (TREE_TYPE
788 (TREE_OPERAND (left_operand
, 0)))
789 || POINTER_TYPE_P (TREE_TYPE
790 (TREE_OPERAND (left_operand
, 0)))))
791 || (((TREE_CODE (left_type
) == RECORD_TYPE
792 && !TYPE_JUSTIFIED_MODULAR_P (left_type
))
793 || TREE_CODE (left_type
) == ARRAY_TYPE
)
794 && ((TREE_CODE (TREE_TYPE
795 (TREE_OPERAND (left_operand
, 0)))
797 || (TREE_CODE (TREE_TYPE
798 (TREE_OPERAND (left_operand
, 0)))
800 && (TYPE_MODE (right_type
) == BLKmode
801 || (TYPE_MODE (left_type
)
802 == TYPE_MODE (TREE_TYPE
804 (left_operand
, 0))))))))
806 left_operand
= TREE_OPERAND (left_operand
, 0);
807 left_type
= TREE_TYPE (left_operand
);
810 /* If a class-wide type may be involved, force use of the RHS type. */
811 if ((TREE_CODE (right_type
) == RECORD_TYPE
812 || TREE_CODE (right_type
) == UNION_TYPE
)
813 && TYPE_ALIGN_OK (right_type
))
814 operation_type
= right_type
;
816 /* If we are copying between padded objects with compatible types, use
817 the padded view of the objects, this is very likely more efficient.
818 Likewise for a padded object that is assigned a constructor, if we
819 can convert the constructor to the inner type, to avoid putting a
820 VIEW_CONVERT_EXPR on the LHS. But don't do so if we wouldn't have
821 actually copied anything. */
822 else if (TYPE_IS_PADDING_P (left_type
)
823 && TREE_CONSTANT (TYPE_SIZE (left_type
))
824 && ((TREE_CODE (right_operand
) == COMPONENT_REF
825 && TYPE_MAIN_VARIANT (left_type
)
827 (TREE_TYPE (TREE_OPERAND (right_operand
, 0))))
828 || (TREE_CODE (right_operand
) == CONSTRUCTOR
829 && !CONTAINS_PLACEHOLDER_P
830 (DECL_SIZE (TYPE_FIELDS (left_type
)))))
831 && !integer_zerop (TYPE_SIZE (right_type
)))
833 /* We make an exception for a BLKmode type padding a non-BLKmode
834 inner type and do the conversion of the LHS right away, since
835 unchecked_convert wouldn't do it properly. */
836 if (TYPE_MODE (left_type
) == BLKmode
837 && TYPE_MODE (right_type
) != BLKmode
838 && TREE_CODE (right_operand
) != CONSTRUCTOR
)
840 operation_type
= right_type
;
841 left_operand
= convert (operation_type
, left_operand
);
842 left_type
= operation_type
;
845 operation_type
= left_type
;
848 /* If we have a call to a function that returns an unconstrained type
849 with default discriminant on the RHS, use the RHS type (which is
850 padded) as we cannot compute the size of the actual assignment. */
851 else if (TREE_CODE (right_operand
) == CALL_EXPR
852 && TYPE_IS_PADDING_P (right_type
)
853 && CONTAINS_PLACEHOLDER_P
854 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (right_type
)))))
855 operation_type
= right_type
;
857 /* Find the best type to use for copying between aggregate types. */
858 else if (((TREE_CODE (left_type
) == ARRAY_TYPE
859 && TREE_CODE (right_type
) == ARRAY_TYPE
)
860 || (TREE_CODE (left_type
) == RECORD_TYPE
861 && TREE_CODE (right_type
) == RECORD_TYPE
))
862 && (best_type
= find_common_type (left_type
, right_type
)))
863 operation_type
= best_type
;
865 /* Otherwise use the LHS type. */
867 operation_type
= left_type
;
869 /* Ensure everything on the LHS is valid. If we have a field reference,
870 strip anything that get_inner_reference can handle. Then remove any
871 conversions between types having the same code and mode. And mark
872 VIEW_CONVERT_EXPRs with TREE_ADDRESSABLE. When done, we must have
873 either an INDIRECT_REF, a NULL_EXPR or a DECL node. */
874 result
= left_operand
;
877 tree restype
= TREE_TYPE (result
);
879 if (TREE_CODE (result
) == COMPONENT_REF
880 || TREE_CODE (result
) == ARRAY_REF
881 || TREE_CODE (result
) == ARRAY_RANGE_REF
)
882 while (handled_component_p (result
))
883 result
= TREE_OPERAND (result
, 0);
884 else if (TREE_CODE (result
) == REALPART_EXPR
885 || TREE_CODE (result
) == IMAGPART_EXPR
886 || (CONVERT_EXPR_P (result
)
887 && (((TREE_CODE (restype
)
888 == TREE_CODE (TREE_TYPE
889 (TREE_OPERAND (result
, 0))))
890 && (TYPE_MODE (TREE_TYPE
891 (TREE_OPERAND (result
, 0)))
892 == TYPE_MODE (restype
)))
893 || TYPE_ALIGN_OK (restype
))))
894 result
= TREE_OPERAND (result
, 0);
895 else if (TREE_CODE (result
) == VIEW_CONVERT_EXPR
)
897 TREE_ADDRESSABLE (result
) = 1;
898 result
= TREE_OPERAND (result
, 0);
904 gcc_assert (TREE_CODE (result
) == INDIRECT_REF
905 || TREE_CODE (result
) == NULL_EXPR
908 /* Convert the right operand to the operation type unless it is
909 either already of the correct type or if the type involves a
910 placeholder, since the RHS may not have the same record type. */
911 if (operation_type
!= right_type
912 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (operation_type
)))
914 right_operand
= convert (operation_type
, right_operand
);
915 right_type
= operation_type
;
918 /* If the left operand is not of the same type as the operation
919 type, wrap it up in a VIEW_CONVERT_EXPR. */
920 if (left_type
!= operation_type
)
921 left_operand
= unchecked_convert (operation_type
, left_operand
, false);
923 has_side_effects
= true;
929 operation_type
= TREE_TYPE (left_type
);
931 /* ... fall through ... */
933 case ARRAY_RANGE_REF
:
934 /* First look through conversion between type variants. Note that
935 this changes neither the operation type nor the type domain. */
936 if (TREE_CODE (left_operand
) == VIEW_CONVERT_EXPR
937 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (left_operand
, 0)))
938 == TYPE_MAIN_VARIANT (left_type
))
940 left_operand
= TREE_OPERAND (left_operand
, 0);
941 left_type
= TREE_TYPE (left_operand
);
944 /* For a range, make sure the element type is consistent. */
945 if (op_code
== ARRAY_RANGE_REF
946 && TREE_TYPE (operation_type
) != TREE_TYPE (left_type
))
947 operation_type
= build_array_type (TREE_TYPE (left_type
),
948 TYPE_DOMAIN (operation_type
));
950 /* Then convert the right operand to its base type. This will prevent
951 unneeded sign conversions when sizetype is wider than integer. */
952 right_operand
= convert (right_base_type
, right_operand
);
953 right_operand
= convert_to_index_type (right_operand
);
957 case TRUTH_ANDIF_EXPR
:
958 case TRUTH_ORIF_EXPR
:
962 #ifdef ENABLE_CHECKING
963 gcc_assert (TREE_CODE (get_base_type (result_type
)) == BOOLEAN_TYPE
);
965 operation_type
= left_base_type
;
966 left_operand
= convert (operation_type
, left_operand
);
967 right_operand
= convert (operation_type
, right_operand
);
976 #ifdef ENABLE_CHECKING
977 gcc_assert (TREE_CODE (get_base_type (result_type
)) == BOOLEAN_TYPE
);
979 /* If either operand is a NULL_EXPR, just return a new one. */
980 if (TREE_CODE (left_operand
) == NULL_EXPR
)
981 return build2 (op_code
, result_type
,
982 build1 (NULL_EXPR
, integer_type_node
,
983 TREE_OPERAND (left_operand
, 0)),
986 else if (TREE_CODE (right_operand
) == NULL_EXPR
)
987 return build2 (op_code
, result_type
,
988 build1 (NULL_EXPR
, integer_type_node
,
989 TREE_OPERAND (right_operand
, 0)),
992 /* If either object is a justified modular types, get the
993 fields from within. */
994 if (TREE_CODE (left_type
) == RECORD_TYPE
995 && TYPE_JUSTIFIED_MODULAR_P (left_type
))
997 left_operand
= convert (TREE_TYPE (TYPE_FIELDS (left_type
)),
999 left_type
= TREE_TYPE (left_operand
);
1000 left_base_type
= get_base_type (left_type
);
1003 if (TREE_CODE (right_type
) == RECORD_TYPE
1004 && TYPE_JUSTIFIED_MODULAR_P (right_type
))
1006 right_operand
= convert (TREE_TYPE (TYPE_FIELDS (right_type
)),
1008 right_type
= TREE_TYPE (right_operand
);
1009 right_base_type
= get_base_type (right_type
);
1012 /* If both objects are arrays, compare them specially. */
1013 if ((TREE_CODE (left_type
) == ARRAY_TYPE
1014 || (TREE_CODE (left_type
) == INTEGER_TYPE
1015 && TYPE_HAS_ACTUAL_BOUNDS_P (left_type
)))
1016 && (TREE_CODE (right_type
) == ARRAY_TYPE
1017 || (TREE_CODE (right_type
) == INTEGER_TYPE
1018 && TYPE_HAS_ACTUAL_BOUNDS_P (right_type
))))
1020 result
= compare_arrays (input_location
,
1021 result_type
, left_operand
, right_operand
);
1022 if (op_code
== NE_EXPR
)
1023 result
= invert_truthvalue_loc (EXPR_LOCATION (result
), result
);
1025 gcc_assert (op_code
== EQ_EXPR
);
1030 /* Otherwise, the base types must be the same, unless they are both fat
1031 pointer types or record types. In the latter case, use the best type
1032 and convert both operands to that type. */
1033 if (left_base_type
!= right_base_type
)
1035 if (TYPE_IS_FAT_POINTER_P (left_base_type
)
1036 && TYPE_IS_FAT_POINTER_P (right_base_type
))
1038 gcc_assert (TYPE_MAIN_VARIANT (left_base_type
)
1039 == TYPE_MAIN_VARIANT (right_base_type
));
1040 best_type
= left_base_type
;
1043 else if (TREE_CODE (left_base_type
) == RECORD_TYPE
1044 && TREE_CODE (right_base_type
) == RECORD_TYPE
)
1046 /* The only way this is permitted is if both types have the same
1047 name. In that case, one of them must not be self-referential.
1048 Use it as the best type. Even better with a fixed size. */
1049 gcc_assert (TYPE_NAME (left_base_type
)
1050 && TYPE_NAME (left_base_type
)
1051 == TYPE_NAME (right_base_type
));
1053 if (TREE_CONSTANT (TYPE_SIZE (left_base_type
)))
1054 best_type
= left_base_type
;
1055 else if (TREE_CONSTANT (TYPE_SIZE (right_base_type
)))
1056 best_type
= right_base_type
;
1057 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (left_base_type
)))
1058 best_type
= left_base_type
;
1059 else if (!CONTAINS_PLACEHOLDER_P (TYPE_SIZE (right_base_type
)))
1060 best_type
= right_base_type
;
1068 left_operand
= convert (best_type
, left_operand
);
1069 right_operand
= convert (best_type
, right_operand
);
1073 left_operand
= convert (left_base_type
, left_operand
);
1074 right_operand
= convert (right_base_type
, right_operand
);
1077 /* If both objects are fat pointers, compare them specially. */
1078 if (TYPE_IS_FAT_POINTER_P (left_base_type
))
1081 = compare_fat_pointers (input_location
,
1082 result_type
, left_operand
, right_operand
);
1083 if (op_code
== NE_EXPR
)
1084 result
= invert_truthvalue_loc (EXPR_LOCATION (result
), result
);
1086 gcc_assert (op_code
== EQ_EXPR
);
1091 modulus
= NULL_TREE
;
1098 /* The RHS of a shift can be any type. Also, ignore any modulus
1099 (we used to abort, but this is needed for unchecked conversion
1100 to modular types). Otherwise, processing is the same as normal. */
1101 gcc_assert (operation_type
== left_base_type
);
1102 modulus
= NULL_TREE
;
1103 left_operand
= convert (operation_type
, left_operand
);
1109 /* For binary modulus, if the inputs are in range, so are the
1111 if (modulus
&& integer_pow2p (modulus
))
1112 modulus
= NULL_TREE
;
1116 gcc_assert (TREE_TYPE (result_type
) == left_base_type
1117 && TREE_TYPE (result_type
) == right_base_type
);
1118 left_operand
= convert (left_base_type
, left_operand
);
1119 right_operand
= convert (right_base_type
, right_operand
);
1122 case TRUNC_DIV_EXPR
: case TRUNC_MOD_EXPR
:
1123 case CEIL_DIV_EXPR
: case CEIL_MOD_EXPR
:
1124 case FLOOR_DIV_EXPR
: case FLOOR_MOD_EXPR
:
1125 case ROUND_DIV_EXPR
: case ROUND_MOD_EXPR
:
1126 /* These always produce results lower than either operand. */
1127 modulus
= NULL_TREE
;
1130 case POINTER_PLUS_EXPR
:
1131 gcc_assert (operation_type
== left_base_type
1132 && sizetype
== right_base_type
);
1133 left_operand
= convert (operation_type
, left_operand
);
1134 right_operand
= convert (sizetype
, right_operand
);
1137 case PLUS_NOMOD_EXPR
:
1138 case MINUS_NOMOD_EXPR
:
1139 if (op_code
== PLUS_NOMOD_EXPR
)
1140 op_code
= PLUS_EXPR
;
1142 op_code
= MINUS_EXPR
;
1143 modulus
= NULL_TREE
;
1145 /* ... fall through ... */
1149 /* Avoid doing arithmetics in ENUMERAL_TYPE or BOOLEAN_TYPE like the
1150 other compilers. Contrary to C, Ada doesn't allow arithmetics in
1151 these types but can generate addition/subtraction for Succ/Pred. */
1153 && (TREE_CODE (operation_type
) == ENUMERAL_TYPE
1154 || TREE_CODE (operation_type
) == BOOLEAN_TYPE
))
1155 operation_type
= left_base_type
= right_base_type
1156 = gnat_type_for_mode (TYPE_MODE (operation_type
),
1157 TYPE_UNSIGNED (operation_type
));
1159 /* ... fall through ... */
1163 /* The result type should be the same as the base types of the
1164 both operands (and they should be the same). Convert
1165 everything to the result type. */
1167 gcc_assert (operation_type
== left_base_type
1168 && left_base_type
== right_base_type
);
1169 left_operand
= convert (operation_type
, left_operand
);
1170 right_operand
= convert (operation_type
, right_operand
);
1173 if (modulus
&& !integer_pow2p (modulus
))
1175 result
= nonbinary_modular_operation (op_code
, operation_type
,
1176 left_operand
, right_operand
);
1177 modulus
= NULL_TREE
;
1179 /* If either operand is a NULL_EXPR, just return a new one. */
1180 else if (TREE_CODE (left_operand
) == NULL_EXPR
)
1181 return build1 (NULL_EXPR
, operation_type
, TREE_OPERAND (left_operand
, 0));
1182 else if (TREE_CODE (right_operand
) == NULL_EXPR
)
1183 return build1 (NULL_EXPR
, operation_type
, TREE_OPERAND (right_operand
, 0));
1184 else if (op_code
== ARRAY_REF
|| op_code
== ARRAY_RANGE_REF
)
1185 result
= fold (build4 (op_code
, operation_type
, left_operand
,
1186 right_operand
, NULL_TREE
, NULL_TREE
));
1187 else if (op_code
== INIT_EXPR
|| op_code
== MODIFY_EXPR
)
1188 result
= build2 (op_code
, void_type_node
, left_operand
, right_operand
);
1191 = fold_build2 (op_code
, operation_type
, left_operand
, right_operand
);
1193 if (TREE_CONSTANT (result
))
1195 else if (op_code
== ARRAY_REF
|| op_code
== ARRAY_RANGE_REF
)
1197 if (TYPE_VOLATILE (operation_type
))
1198 TREE_THIS_VOLATILE (result
) = 1;
1201 TREE_CONSTANT (result
)
1202 |= (TREE_CONSTANT (left_operand
) && TREE_CONSTANT (right_operand
));
1204 TREE_SIDE_EFFECTS (result
) |= has_side_effects
;
1206 /* If we are working with modular types, perform the MOD operation
1207 if something above hasn't eliminated the need for it. */
1209 result
= fold_build2 (FLOOR_MOD_EXPR
, operation_type
, result
,
1210 convert (operation_type
, modulus
));
1212 if (result_type
&& result_type
!= operation_type
)
1213 result
= convert (result_type
, result
);
1218 /* Similar, but for unary operations. */
1221 build_unary_op (enum tree_code op_code
, tree result_type
, tree operand
)
1223 tree type
= TREE_TYPE (operand
);
1224 tree base_type
= get_base_type (type
);
1225 tree operation_type
= result_type
;
1229 && TREE_CODE (operation_type
) == RECORD_TYPE
1230 && TYPE_JUSTIFIED_MODULAR_P (operation_type
))
1231 operation_type
= TREE_TYPE (TYPE_FIELDS (operation_type
));
1234 && TREE_CODE (operation_type
) == INTEGER_TYPE
1235 && TYPE_EXTRA_SUBTYPE_P (operation_type
))
1236 operation_type
= get_base_type (operation_type
);
1242 if (!operation_type
)
1243 result_type
= operation_type
= TREE_TYPE (type
);
1245 gcc_assert (result_type
== TREE_TYPE (type
));
1247 result
= fold_build1 (op_code
, operation_type
, operand
);
1250 case TRUTH_NOT_EXPR
:
1251 #ifdef ENABLE_CHECKING
1252 gcc_assert (TREE_CODE (get_base_type (result_type
)) == BOOLEAN_TYPE
);
1254 result
= invert_truthvalue_loc (EXPR_LOCATION (operand
), operand
);
1255 /* When not optimizing, fold the result as invert_truthvalue_loc
1256 doesn't fold the result of comparisons. This is intended to undo
1257 the trick used for boolean rvalues in gnat_to_gnu. */
1259 result
= fold (result
);
1262 case ATTR_ADDR_EXPR
:
1264 switch (TREE_CODE (operand
))
1267 case UNCONSTRAINED_ARRAY_REF
:
1268 result
= TREE_OPERAND (operand
, 0);
1270 /* Make sure the type here is a pointer, not a reference.
1271 GCC wants pointer types for function addresses. */
1273 result_type
= build_pointer_type (type
);
1275 /* If the underlying object can alias everything, propagate the
1276 property since we are effectively retrieving the object. */
1277 if (POINTER_TYPE_P (TREE_TYPE (result
))
1278 && TYPE_REF_CAN_ALIAS_ALL (TREE_TYPE (result
)))
1280 if (TREE_CODE (result_type
) == POINTER_TYPE
1281 && !TYPE_REF_CAN_ALIAS_ALL (result_type
))
1283 = build_pointer_type_for_mode (TREE_TYPE (result_type
),
1284 TYPE_MODE (result_type
),
1286 else if (TREE_CODE (result_type
) == REFERENCE_TYPE
1287 && !TYPE_REF_CAN_ALIAS_ALL (result_type
))
1289 = build_reference_type_for_mode (TREE_TYPE (result_type
),
1290 TYPE_MODE (result_type
),
1297 TREE_TYPE (result
) = type
= build_pointer_type (type
);
1301 /* Fold a compound expression if it has unconstrained array type
1302 since the middle-end cannot handle it. But we don't it in the
1303 general case because it may introduce aliasing issues if the
1304 first operand is an indirect assignment and the second operand
1305 the corresponding address, e.g. for an allocator. */
1306 if (TREE_CODE (type
) == UNCONSTRAINED_ARRAY_TYPE
)
1308 result
= build_unary_op (ADDR_EXPR
, result_type
,
1309 TREE_OPERAND (operand
, 1));
1310 result
= build2 (COMPOUND_EXPR
, TREE_TYPE (result
),
1311 TREE_OPERAND (operand
, 0), result
);
1317 case ARRAY_RANGE_REF
:
1320 /* If this is for 'Address, find the address of the prefix and add
1321 the offset to the field. Otherwise, do this the normal way. */
1322 if (op_code
== ATTR_ADDR_EXPR
)
1324 HOST_WIDE_INT bitsize
;
1325 HOST_WIDE_INT bitpos
;
1328 int unsignedp
, volatilep
;
1330 inner
= get_inner_reference (operand
, &bitsize
, &bitpos
, &offset
,
1331 &mode
, &unsignedp
, &volatilep
,
1334 /* If INNER is a padding type whose field has a self-referential
1335 size, convert to that inner type. We know the offset is zero
1336 and we need to have that type visible. */
1337 if (TYPE_IS_PADDING_P (TREE_TYPE (inner
))
1338 && CONTAINS_PLACEHOLDER_P
1339 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS
1340 (TREE_TYPE (inner
))))))
1341 inner
= convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (inner
))),
1344 /* Compute the offset as a byte offset from INNER. */
1346 offset
= size_zero_node
;
1348 offset
= size_binop (PLUS_EXPR
, offset
,
1349 size_int (bitpos
/ BITS_PER_UNIT
));
1351 /* Take the address of INNER, convert the offset to void *, and
1352 add then. It will later be converted to the desired result
1354 inner
= build_unary_op (ADDR_EXPR
, NULL_TREE
, inner
);
1355 inner
= convert (ptr_void_type_node
, inner
);
1356 result
= build_binary_op (POINTER_PLUS_EXPR
, ptr_void_type_node
,
1358 result
= convert (build_pointer_type (TREE_TYPE (operand
)),
1365 /* If this is just a constructor for a padded record, we can
1366 just take the address of the single field and convert it to
1367 a pointer to our type. */
1368 if (TYPE_IS_PADDING_P (type
))
1370 result
= (*CONSTRUCTOR_ELTS (operand
))[0].value
;
1371 result
= convert (build_pointer_type (TREE_TYPE (operand
)),
1372 build_unary_op (ADDR_EXPR
, NULL_TREE
, result
));
1379 if (AGGREGATE_TYPE_P (type
)
1380 && AGGREGATE_TYPE_P (TREE_TYPE (TREE_OPERAND (operand
, 0))))
1381 return build_unary_op (ADDR_EXPR
, result_type
,
1382 TREE_OPERAND (operand
, 0));
1384 /* ... fallthru ... */
1386 case VIEW_CONVERT_EXPR
:
1387 /* If this just a variant conversion or if the conversion doesn't
1388 change the mode, get the result type from this type and go down.
1389 This is needed for conversions of CONST_DECLs, to eventually get
1390 to the address of their CORRESPONDING_VARs. */
1391 if ((TYPE_MAIN_VARIANT (type
)
1392 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (operand
, 0))))
1393 || (TYPE_MODE (type
) != BLKmode
1394 && (TYPE_MODE (type
)
1395 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (operand
, 0))))))
1396 return build_unary_op (ADDR_EXPR
,
1397 (result_type
? result_type
1398 : build_pointer_type (type
)),
1399 TREE_OPERAND (operand
, 0));
1403 operand
= DECL_CONST_CORRESPONDING_VAR (operand
);
1405 /* ... fall through ... */
1410 /* If we are taking the address of a padded record whose field
1411 contains a template, take the address of the field. */
1412 if (TYPE_IS_PADDING_P (type
)
1413 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (type
))) == RECORD_TYPE
1414 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (type
))))
1416 type
= TREE_TYPE (TYPE_FIELDS (type
));
1417 operand
= convert (type
, operand
);
1420 gnat_mark_addressable (operand
);
1421 result
= build_fold_addr_expr (operand
);
1424 TREE_CONSTANT (result
) = staticp (operand
) || TREE_CONSTANT (operand
);
1429 tree t
= remove_conversions (operand
, false);
1430 bool can_never_be_null
= DECL_P (t
) && DECL_CAN_NEVER_BE_NULL_P (t
);
1432 /* If TYPE is a thin pointer, either first retrieve the base if this
1433 is an expression with an offset built for the initialization of an
1434 object with an unconstrained nominal subtype, or else convert to
1436 if (TYPE_IS_THIN_POINTER_P (type
))
1438 tree rec_type
= TREE_TYPE (type
);
1440 if (TREE_CODE (operand
) == POINTER_PLUS_EXPR
1441 && TREE_OPERAND (operand
, 1)
1442 == byte_position (DECL_CHAIN (TYPE_FIELDS (rec_type
)))
1443 && TREE_CODE (TREE_OPERAND (operand
, 0)) == NOP_EXPR
)
1445 operand
= TREE_OPERAND (TREE_OPERAND (operand
, 0), 0);
1446 type
= TREE_TYPE (operand
);
1448 else if (TYPE_UNCONSTRAINED_ARRAY (rec_type
))
1451 = convert (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (rec_type
)),
1453 type
= TREE_TYPE (operand
);
1457 /* If we want to refer to an unconstrained array, use the appropriate
1458 expression. But this will never survive down to the back-end. */
1459 if (TYPE_IS_FAT_POINTER_P (type
))
1461 result
= build1 (UNCONSTRAINED_ARRAY_REF
,
1462 TYPE_UNCONSTRAINED_ARRAY (type
), operand
);
1463 TREE_READONLY (result
)
1464 = TYPE_READONLY (TYPE_UNCONSTRAINED_ARRAY (type
));
1467 /* If we are dereferencing an ADDR_EXPR, return its operand. */
1468 else if (TREE_CODE (operand
) == ADDR_EXPR
)
1469 result
= TREE_OPERAND (operand
, 0);
1471 /* Otherwise, build and fold the indirect reference. */
1474 result
= build_fold_indirect_ref (operand
);
1475 TREE_READONLY (result
) = TYPE_READONLY (TREE_TYPE (type
));
1478 if (!TYPE_IS_FAT_POINTER_P (type
) && TYPE_VOLATILE (TREE_TYPE (type
)))
1480 TREE_SIDE_EFFECTS (result
) = 1;
1481 if (TREE_CODE (result
) == INDIRECT_REF
)
1482 TREE_THIS_VOLATILE (result
) = TYPE_VOLATILE (TREE_TYPE (result
));
1485 if ((TREE_CODE (result
) == INDIRECT_REF
1486 || TREE_CODE (result
) == UNCONSTRAINED_ARRAY_REF
)
1487 && can_never_be_null
)
1488 TREE_THIS_NOTRAP (result
) = 1;
1496 tree modulus
= ((operation_type
1497 && TREE_CODE (operation_type
) == INTEGER_TYPE
1498 && TYPE_MODULAR_P (operation_type
))
1499 ? TYPE_MODULUS (operation_type
) : NULL_TREE
);
1500 int mod_pow2
= modulus
&& integer_pow2p (modulus
);
1502 /* If this is a modular type, there are various possibilities
1503 depending on the operation and whether the modulus is a
1504 power of two or not. */
1508 gcc_assert (operation_type
== base_type
);
1509 operand
= convert (operation_type
, operand
);
1511 /* The fastest in the negate case for binary modulus is
1512 the straightforward code; the TRUNC_MOD_EXPR below
1513 is an AND operation. */
1514 if (op_code
== NEGATE_EXPR
&& mod_pow2
)
1515 result
= fold_build2 (TRUNC_MOD_EXPR
, operation_type
,
1516 fold_build1 (NEGATE_EXPR
, operation_type
,
1520 /* For nonbinary negate case, return zero for zero operand,
1521 else return the modulus minus the operand. If the modulus
1522 is a power of two minus one, we can do the subtraction
1523 as an XOR since it is equivalent and faster on most machines. */
1524 else if (op_code
== NEGATE_EXPR
&& !mod_pow2
)
1526 if (integer_pow2p (fold_build2 (PLUS_EXPR
, operation_type
,
1528 convert (operation_type
,
1529 integer_one_node
))))
1530 result
= fold_build2 (BIT_XOR_EXPR
, operation_type
,
1533 result
= fold_build2 (MINUS_EXPR
, operation_type
,
1536 result
= fold_build3 (COND_EXPR
, operation_type
,
1537 fold_build2 (NE_EXPR
,
1542 integer_zero_node
)),
1547 /* For the NOT cases, we need a constant equal to
1548 the modulus minus one. For a binary modulus, we
1549 XOR against the constant and subtract the operand from
1550 that constant for nonbinary modulus. */
1552 tree cnst
= fold_build2 (MINUS_EXPR
, operation_type
, modulus
,
1553 convert (operation_type
,
1557 result
= fold_build2 (BIT_XOR_EXPR
, operation_type
,
1560 result
= fold_build2 (MINUS_EXPR
, operation_type
,
1568 /* ... fall through ... */
1571 gcc_assert (operation_type
== base_type
);
1572 result
= fold_build1 (op_code
, operation_type
,
1573 convert (operation_type
, operand
));
1576 if (result_type
&& TREE_TYPE (result
) != result_type
)
1577 result
= convert (result_type
, result
);
1582 /* Similar, but for COND_EXPR. */
1585 build_cond_expr (tree result_type
, tree condition_operand
,
1586 tree true_operand
, tree false_operand
)
1588 bool addr_p
= false;
1591 /* The front-end verified that result, true and false operands have
1592 same base type. Convert everything to the result type. */
1593 true_operand
= convert (result_type
, true_operand
);
1594 false_operand
= convert (result_type
, false_operand
);
1596 /* If the result type is unconstrained, take the address of the operands and
1597 then dereference the result. Likewise if the result type is passed by
1598 reference, because creating a temporary of this type is not allowed. */
1599 if (TREE_CODE (result_type
) == UNCONSTRAINED_ARRAY_TYPE
1600 || TYPE_IS_BY_REFERENCE_P (result_type
)
1601 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type
)))
1603 result_type
= build_pointer_type (result_type
);
1604 true_operand
= build_unary_op (ADDR_EXPR
, result_type
, true_operand
);
1605 false_operand
= build_unary_op (ADDR_EXPR
, result_type
, false_operand
);
1609 result
= fold_build3 (COND_EXPR
, result_type
, condition_operand
,
1610 true_operand
, false_operand
);
1612 /* If we have a common SAVE_EXPR (possibly surrounded by arithmetics)
1613 in both arms, make sure it gets evaluated by moving it ahead of the
1614 conditional expression. This is necessary because it is evaluated
1615 in only one place at run time and would otherwise be uninitialized
1616 in one of the arms. */
1617 true_operand
= skip_simple_arithmetic (true_operand
);
1618 false_operand
= skip_simple_arithmetic (false_operand
);
1620 if (true_operand
== false_operand
&& TREE_CODE (true_operand
) == SAVE_EXPR
)
1621 result
= build2 (COMPOUND_EXPR
, result_type
, true_operand
, result
);
1624 result
= build_unary_op (INDIRECT_REF
, NULL_TREE
, result
);
1629 /* Similar, but for COMPOUND_EXPR. */
1632 build_compound_expr (tree result_type
, tree stmt_operand
, tree expr_operand
)
1634 bool addr_p
= false;
1637 /* If the result type is unconstrained, take the address of the operand and
1638 then dereference the result. Likewise if the result type is passed by
1639 reference, but this is natively handled in the gimplifier. */
1640 if (TREE_CODE (result_type
) == UNCONSTRAINED_ARRAY_TYPE
1641 || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (result_type
)))
1643 result_type
= build_pointer_type (result_type
);
1644 expr_operand
= build_unary_op (ADDR_EXPR
, result_type
, expr_operand
);
1648 result
= fold_build2 (COMPOUND_EXPR
, result_type
, stmt_operand
,
1652 result
= build_unary_op (INDIRECT_REF
, NULL_TREE
, result
);
1657 /* Conveniently construct a function call expression. FNDECL names the
1658 function to be called, N is the number of arguments, and the "..."
1659 parameters are the argument expressions. Unlike build_call_expr
1660 this doesn't fold the call, hence it will always return a CALL_EXPR. */
1663 build_call_n_expr (tree fndecl
, int n
, ...)
1666 tree fntype
= TREE_TYPE (fndecl
);
1667 tree fn
= build1 (ADDR_EXPR
, build_pointer_type (fntype
), fndecl
);
1670 fn
= build_call_valist (TREE_TYPE (fntype
), fn
, n
, ap
);
1675 /* Call a function that raises an exception and pass the line number and file
1676 name, if requested. MSG says which exception function to call.
1678 GNAT_NODE is the gnat node conveying the source location for which the
1679 error should be signaled, or Empty in which case the error is signaled on
1680 the current ref_file_name/input_line.
1682 KIND says which kind of exception this is for
1683 (N_Raise_{Constraint,Storage,Program}_Error). */
1686 build_call_raise (int msg
, Node_Id gnat_node
, char kind
)
1688 tree fndecl
= gnat_raise_decls
[msg
];
1689 tree label
= get_exception_label (kind
);
1695 /* If this is to be done as a goto, handle that case. */
1698 Entity_Id local_raise
= Get_Local_Raise_Call_Entity ();
1699 tree gnu_result
= build1 (GOTO_EXPR
, void_type_node
, label
);
1701 /* If Local_Raise is present, generate
1702 Local_Raise (exception'Identity); */
1703 if (Present (local_raise
))
1705 tree gnu_local_raise
1706 = gnat_to_gnu_entity (local_raise
, NULL_TREE
, 0);
1707 tree gnu_exception_entity
1708 = gnat_to_gnu_entity (Get_RT_Exception_Entity (msg
), NULL_TREE
, 0);
1710 = build_call_n_expr (gnu_local_raise
, 1,
1711 build_unary_op (ADDR_EXPR
, NULL_TREE
,
1712 gnu_exception_entity
));
1714 gnu_result
= build2 (COMPOUND_EXPR
, void_type_node
,
1715 gnu_call
, gnu_result
);}
1721 = (Debug_Flag_NN
|| Exception_Locations_Suppressed
)
1723 : (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1724 ? IDENTIFIER_POINTER
1725 (get_identifier (Get_Name_String
1727 (Get_Source_File_Index (Sloc (gnat_node
))))))
1731 filename
= build_string (len
, str
);
1733 = (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1734 ? Get_Logical_Line_Number (Sloc(gnat_node
))
1735 : LOCATION_LINE (input_location
);
1737 TREE_TYPE (filename
) = build_array_type (unsigned_char_type_node
,
1738 build_index_type (size_int (len
)));
1741 build_call_n_expr (fndecl
, 2,
1743 build_pointer_type (unsigned_char_type_node
),
1745 build_int_cst (NULL_TREE
, line_number
));
1748 /* Similar to build_call_raise, for an index or range check exception as
1749 determined by MSG, with extra information generated of the form
1750 "INDEX out of range FIRST..LAST". */
1753 build_call_raise_range (int msg
, Node_Id gnat_node
,
1754 tree index
, tree first
, tree last
)
1756 tree fndecl
= gnat_raise_decls_ext
[msg
];
1758 int line_number
, column_number
;
1763 = (Debug_Flag_NN
|| Exception_Locations_Suppressed
)
1765 : (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1766 ? IDENTIFIER_POINTER
1767 (get_identifier (Get_Name_String
1769 (Get_Source_File_Index (Sloc (gnat_node
))))))
1773 filename
= build_string (len
, str
);
1774 if (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1776 line_number
= Get_Logical_Line_Number (Sloc (gnat_node
));
1777 column_number
= Get_Column_Number (Sloc (gnat_node
));
1781 line_number
= LOCATION_LINE (input_location
);
1785 TREE_TYPE (filename
) = build_array_type (unsigned_char_type_node
,
1786 build_index_type (size_int (len
)));
1789 build_call_n_expr (fndecl
, 6,
1791 build_pointer_type (unsigned_char_type_node
),
1793 build_int_cst (NULL_TREE
, line_number
),
1794 build_int_cst (NULL_TREE
, column_number
),
1795 convert (integer_type_node
, index
),
1796 convert (integer_type_node
, first
),
1797 convert (integer_type_node
, last
));
1800 /* Similar to build_call_raise, with extra information about the column
1801 where the check failed. */
1804 build_call_raise_column (int msg
, Node_Id gnat_node
)
1806 tree fndecl
= gnat_raise_decls_ext
[msg
];
1808 int line_number
, column_number
;
1813 = (Debug_Flag_NN
|| Exception_Locations_Suppressed
)
1815 : (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1816 ? IDENTIFIER_POINTER
1817 (get_identifier (Get_Name_String
1819 (Get_Source_File_Index (Sloc (gnat_node
))))))
1823 filename
= build_string (len
, str
);
1824 if (gnat_node
!= Empty
&& Sloc (gnat_node
) != No_Location
)
1826 line_number
= Get_Logical_Line_Number (Sloc (gnat_node
));
1827 column_number
= Get_Column_Number (Sloc (gnat_node
));
1831 line_number
= LOCATION_LINE (input_location
);
1835 TREE_TYPE (filename
) = build_array_type (unsigned_char_type_node
,
1836 build_index_type (size_int (len
)));
1839 build_call_n_expr (fndecl
, 3,
1841 build_pointer_type (unsigned_char_type_node
),
1843 build_int_cst (NULL_TREE
, line_number
),
1844 build_int_cst (NULL_TREE
, column_number
));
1847 /* qsort comparer for the bit positions of two constructor elements
1848 for record components. */
1851 compare_elmt_bitpos (const PTR rt1
, const PTR rt2
)
1853 const constructor_elt
* const elmt1
= (const constructor_elt
* const) rt1
;
1854 const constructor_elt
* const elmt2
= (const constructor_elt
* const) rt2
;
1855 const_tree
const field1
= elmt1
->index
;
1856 const_tree
const field2
= elmt2
->index
;
1858 = tree_int_cst_compare (bit_position (field1
), bit_position (field2
));
1860 return ret
? ret
: (int) (DECL_UID (field1
) - DECL_UID (field2
));
1863 /* Return a CONSTRUCTOR of TYPE whose elements are V. */
1866 gnat_build_constructor (tree type
, vec
<constructor_elt
, va_gc
> *v
)
1868 bool allconstant
= (TREE_CODE (TYPE_SIZE (type
)) == INTEGER_CST
);
1869 bool read_only
= true;
1870 bool side_effects
= false;
1871 tree result
, obj
, val
;
1872 unsigned int n_elmts
;
1874 /* Scan the elements to see if they are all constant or if any has side
1875 effects, to let us set global flags on the resulting constructor. Count
1876 the elements along the way for possible sorting purposes below. */
1877 FOR_EACH_CONSTRUCTOR_ELT (v
, n_elmts
, obj
, val
)
1879 /* The predicate must be in keeping with output_constructor. */
1880 if ((!TREE_CONSTANT (val
) && !TREE_STATIC (val
))
1881 || (TREE_CODE (type
) == RECORD_TYPE
1882 && CONSTRUCTOR_BITFIELD_P (obj
)
1883 && !initializer_constant_valid_for_bitfield_p (val
))
1884 || !initializer_constant_valid_p (val
, TREE_TYPE (val
)))
1885 allconstant
= false;
1887 if (!TREE_READONLY (val
))
1890 if (TREE_SIDE_EFFECTS (val
))
1891 side_effects
= true;
1894 /* For record types with constant components only, sort field list
1895 by increasing bit position. This is necessary to ensure the
1896 constructor can be output as static data. */
1897 if (allconstant
&& TREE_CODE (type
) == RECORD_TYPE
&& n_elmts
> 1)
1898 v
->qsort (compare_elmt_bitpos
);
1900 result
= build_constructor (type
, v
);
1901 CONSTRUCTOR_NO_CLEARING (result
) = 1;
1902 TREE_CONSTANT (result
) = TREE_STATIC (result
) = allconstant
;
1903 TREE_SIDE_EFFECTS (result
) = side_effects
;
1904 TREE_READONLY (result
) = TYPE_READONLY (type
) || read_only
|| allconstant
;
1908 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
1909 an IDENTIFIER_NODE giving the name of the field, or FIELD, a FIELD_DECL,
1910 for the field. Don't fold the result if NO_FOLD_P is true.
1912 We also handle the fact that we might have been passed a pointer to the
1913 actual record and know how to look for fields in variant parts. */
1916 build_simple_component_ref (tree record_variable
, tree component
, tree field
,
1919 tree record_type
= TYPE_MAIN_VARIANT (TREE_TYPE (record_variable
));
1922 gcc_assert (RECORD_OR_UNION_TYPE_P (record_type
)
1923 && COMPLETE_TYPE_P (record_type
)
1924 && (component
== NULL_TREE
) != (field
== NULL_TREE
));
1926 /* If no field was specified, look for a field with the specified name in
1927 the current record only. */
1929 for (field
= TYPE_FIELDS (record_type
);
1931 field
= DECL_CHAIN (field
))
1932 if (DECL_NAME (field
) == component
)
1938 /* If this field is not in the specified record, see if we can find a field
1939 in the specified record whose original field is the same as this one. */
1940 if (DECL_CONTEXT (field
) != record_type
)
1944 /* First loop through normal components. */
1945 for (new_field
= TYPE_FIELDS (record_type
);
1947 new_field
= DECL_CHAIN (new_field
))
1948 if (SAME_FIELD_P (field
, new_field
))
1951 /* Next, see if we're looking for an inherited component in an extension.
1952 If so, look through the extension directly, unless the type contains
1953 a placeholder, as it might be needed for a later substitution. */
1955 && TREE_CODE (record_variable
) == VIEW_CONVERT_EXPR
1956 && TYPE_ALIGN_OK (record_type
)
1957 && !type_contains_placeholder_p (record_type
)
1958 && TREE_CODE (TREE_TYPE (TREE_OPERAND (record_variable
, 0)))
1960 && TYPE_ALIGN_OK (TREE_TYPE (TREE_OPERAND (record_variable
, 0))))
1962 ref
= build_simple_component_ref (TREE_OPERAND (record_variable
, 0),
1963 NULL_TREE
, field
, no_fold_p
);
1968 /* Next, loop through DECL_INTERNAL_P components if we haven't found the
1969 component in the first search. Doing this search in two steps is
1970 required to avoid hidden homonymous fields in the _Parent field. */
1972 for (new_field
= TYPE_FIELDS (record_type
);
1974 new_field
= DECL_CHAIN (new_field
))
1975 if (DECL_INTERNAL_P (new_field
))
1978 = build_simple_component_ref (record_variable
,
1979 NULL_TREE
, new_field
, no_fold_p
);
1980 ref
= build_simple_component_ref (field_ref
, NULL_TREE
, field
,
1992 /* If the field's offset has overflowed, do not try to access it, as doing
1993 so may trigger sanity checks deeper in the back-end. Note that we don't
1994 need to warn since this will be done on trying to declare the object. */
1995 if (TREE_CODE (DECL_FIELD_OFFSET (field
)) == INTEGER_CST
1996 && TREE_OVERFLOW (DECL_FIELD_OFFSET (field
)))
1999 /* We have found a suitable field. Before building the COMPONENT_REF, get
2000 the base object of the record variable if possible. */
2001 base
= record_variable
;
2003 if (TREE_CODE (record_variable
) == VIEW_CONVERT_EXPR
)
2005 tree inner_variable
= TREE_OPERAND (record_variable
, 0);
2006 tree inner_type
= TYPE_MAIN_VARIANT (TREE_TYPE (inner_variable
));
2008 /* Look through a conversion between type variants. This is transparent
2009 as far as the field is concerned. */
2010 if (inner_type
== record_type
)
2011 base
= inner_variable
;
2013 /* Look through a conversion between original and packable version, but
2014 the field needs to be adjusted in this case. */
2015 else if (RECORD_OR_UNION_TYPE_P (inner_type
)
2016 && TYPE_NAME (inner_type
) == TYPE_NAME (record_type
))
2020 for (new_field
= TYPE_FIELDS (inner_type
);
2022 new_field
= DECL_CHAIN (new_field
))
2023 if (SAME_FIELD_P (field
, new_field
))
2028 base
= inner_variable
;
2033 ref
= build3 (COMPONENT_REF
, TREE_TYPE (field
), base
, field
, NULL_TREE
);
2035 if (TREE_READONLY (record_variable
)
2036 || TREE_READONLY (field
)
2037 || TYPE_READONLY (record_type
))
2038 TREE_READONLY (ref
) = 1;
2040 if (TREE_THIS_VOLATILE (record_variable
)
2041 || TREE_THIS_VOLATILE (field
)
2042 || TYPE_VOLATILE (record_type
))
2043 TREE_THIS_VOLATILE (ref
) = 1;
2048 /* The generic folder may punt in this case because the inner array type
2049 can be self-referential, but folding is in fact not problematic. */
2050 if (TREE_CODE (base
) == CONSTRUCTOR
2051 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (base
)))
2053 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (base
);
2054 unsigned HOST_WIDE_INT idx
;
2056 FOR_EACH_CONSTRUCTOR_ELT (elts
, idx
, index
, value
)
2065 /* Likewise, but generate a Constraint_Error if the reference could not be
2069 build_component_ref (tree record_variable
, tree component
, tree field
,
2072 tree ref
= build_simple_component_ref (record_variable
, component
, field
,
2077 /* If FIELD was specified, assume this is an invalid user field so raise
2078 Constraint_Error. Otherwise, we have no type to return so abort. */
2080 return build1 (NULL_EXPR
, TREE_TYPE (field
),
2081 build_call_raise (CE_Discriminant_Check_Failed
, Empty
,
2082 N_Raise_Constraint_Error
));
2085 /* Helper for build_call_alloc_dealloc, with arguments to be interpreted
2086 identically. Process the case where a GNAT_PROC to call is provided. */
2089 build_call_alloc_dealloc_proc (tree gnu_obj
, tree gnu_size
, tree gnu_type
,
2090 Entity_Id gnat_proc
, Entity_Id gnat_pool
)
2092 tree gnu_proc
= gnat_to_gnu (gnat_proc
);
2095 /* A storage pool's underlying type is a record type (for both predefined
2096 storage pools and GNAT simple storage pools). The secondary stack uses
2097 the same mechanism, but its pool object (SS_Pool) is an integer. */
2098 if (Is_Record_Type (Underlying_Type (Etype (gnat_pool
))))
2100 /* The size is the third parameter; the alignment is the
2102 Entity_Id gnat_size_type
2103 = Etype (Next_Formal (Next_Formal (First_Formal (gnat_proc
))));
2104 tree gnu_size_type
= gnat_to_gnu_type (gnat_size_type
);
2106 tree gnu_pool
= gnat_to_gnu (gnat_pool
);
2107 tree gnu_pool_addr
= build_unary_op (ADDR_EXPR
, NULL_TREE
, gnu_pool
);
2108 tree gnu_align
= size_int (TYPE_ALIGN (gnu_type
) / BITS_PER_UNIT
);
2110 gnu_size
= convert (gnu_size_type
, gnu_size
);
2111 gnu_align
= convert (gnu_size_type
, gnu_align
);
2113 /* The first arg is always the address of the storage pool; next
2114 comes the address of the object, for a deallocator, then the
2115 size and alignment. */
2117 gnu_call
= build_call_n_expr (gnu_proc
, 4, gnu_pool_addr
, gnu_obj
,
2118 gnu_size
, gnu_align
);
2120 gnu_call
= build_call_n_expr (gnu_proc
, 3, gnu_pool_addr
,
2121 gnu_size
, gnu_align
);
2124 /* Secondary stack case. */
2127 /* The size is the second parameter. */
2128 Entity_Id gnat_size_type
2129 = Etype (Next_Formal (First_Formal (gnat_proc
)));
2130 tree gnu_size_type
= gnat_to_gnu_type (gnat_size_type
);
2132 gnu_size
= convert (gnu_size_type
, gnu_size
);
2134 /* The first arg is the address of the object, for a deallocator,
2137 gnu_call
= build_call_n_expr (gnu_proc
, 2, gnu_obj
, gnu_size
);
2139 gnu_call
= build_call_n_expr (gnu_proc
, 1, gnu_size
);
2145 /* Helper for build_call_alloc_dealloc, to build and return an allocator for
2146 DATA_SIZE bytes aimed at containing a DATA_TYPE object, using the default
2147 __gnat_malloc allocator. Honor DATA_TYPE alignments greater than what the
2151 maybe_wrap_malloc (tree data_size
, tree data_type
, Node_Id gnat_node
)
2153 /* When the DATA_TYPE alignment is stricter than what malloc offers
2154 (super-aligned case), we allocate an "aligning" wrapper type and return
2155 the address of its single data field with the malloc's return value
2156 stored just in front. */
2158 unsigned int data_align
= TYPE_ALIGN (data_type
);
2159 unsigned int system_allocator_alignment
2160 = get_target_system_allocator_alignment () * BITS_PER_UNIT
;
2163 = ((data_align
> system_allocator_alignment
)
2164 ? make_aligning_type (data_type
, data_align
, data_size
,
2165 system_allocator_alignment
,
2166 POINTER_SIZE
/ BITS_PER_UNIT
,
2171 = aligning_type
? TYPE_SIZE_UNIT (aligning_type
) : data_size
;
2173 tree malloc_ptr
= build_call_n_expr (malloc_decl
, 1, size_to_malloc
);
2177 /* Latch malloc's return value and get a pointer to the aligning field
2179 tree storage_ptr
= gnat_protect_expr (malloc_ptr
);
2181 tree aligning_record_addr
2182 = convert (build_pointer_type (aligning_type
), storage_ptr
);
2184 tree aligning_record
2185 = build_unary_op (INDIRECT_REF
, NULL_TREE
, aligning_record_addr
);
2188 = build_component_ref (aligning_record
, NULL_TREE
,
2189 TYPE_FIELDS (aligning_type
), false);
2191 tree aligning_field_addr
2192 = build_unary_op (ADDR_EXPR
, NULL_TREE
, aligning_field
);
2194 /* Then arrange to store the allocator's return value ahead
2196 tree storage_ptr_slot_addr
2197 = build_binary_op (POINTER_PLUS_EXPR
, ptr_void_type_node
,
2198 convert (ptr_void_type_node
, aligning_field_addr
),
2199 size_int (-(HOST_WIDE_INT
) POINTER_SIZE
2202 tree storage_ptr_slot
2203 = build_unary_op (INDIRECT_REF
, NULL_TREE
,
2204 convert (build_pointer_type (ptr_void_type_node
),
2205 storage_ptr_slot_addr
));
2208 build2 (COMPOUND_EXPR
, TREE_TYPE (aligning_field_addr
),
2209 build_binary_op (INIT_EXPR
, NULL_TREE
,
2210 storage_ptr_slot
, storage_ptr
),
2211 aligning_field_addr
);
2217 /* Helper for build_call_alloc_dealloc, to release a DATA_TYPE object
2218 designated by DATA_PTR using the __gnat_free entry point. */
2221 maybe_wrap_free (tree data_ptr
, tree data_type
)
2223 /* In the regular alignment case, we pass the data pointer straight to free.
2224 In the superaligned case, we need to retrieve the initial allocator
2225 return value, stored in front of the data block at allocation time. */
2227 unsigned int data_align
= TYPE_ALIGN (data_type
);
2228 unsigned int system_allocator_alignment
2229 = get_target_system_allocator_alignment () * BITS_PER_UNIT
;
2233 if (data_align
> system_allocator_alignment
)
2235 /* DATA_FRONT_PTR (void *)
2236 = (void *)DATA_PTR - (void *)sizeof (void *)) */
2239 (POINTER_PLUS_EXPR
, ptr_void_type_node
,
2240 convert (ptr_void_type_node
, data_ptr
),
2241 size_int (-(HOST_WIDE_INT
) POINTER_SIZE
/ BITS_PER_UNIT
));
2243 /* FREE_PTR (void *) = *(void **)DATA_FRONT_PTR */
2246 (INDIRECT_REF
, NULL_TREE
,
2247 convert (build_pointer_type (ptr_void_type_node
), data_front_ptr
));
2250 free_ptr
= data_ptr
;
2252 return build_call_n_expr (free_decl
, 1, free_ptr
);
2255 /* Build a GCC tree to call an allocation or deallocation function.
2256 If GNU_OBJ is nonzero, it is an object to deallocate. Otherwise,
2257 generate an allocator.
2259 GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
2260 object type, used to determine the to-be-honored address alignment.
2261 GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
2262 pool to use. If not present, malloc and free are used. GNAT_NODE is used
2263 to provide an error location for restriction violation messages. */
2266 build_call_alloc_dealloc (tree gnu_obj
, tree gnu_size
, tree gnu_type
,
2267 Entity_Id gnat_proc
, Entity_Id gnat_pool
,
2270 gnu_size
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size
, gnu_obj
);
2272 /* Explicit proc to call ? This one is assumed to deal with the type
2273 alignment constraints. */
2274 if (Present (gnat_proc
))
2275 return build_call_alloc_dealloc_proc (gnu_obj
, gnu_size
, gnu_type
,
2276 gnat_proc
, gnat_pool
);
2278 /* Otherwise, object to "free" or "malloc" with possible special processing
2279 for alignments stricter than what the default allocator honors. */
2281 return maybe_wrap_free (gnu_obj
, gnu_type
);
2284 /* Assert that we no longer can be called with this special pool. */
2285 gcc_assert (gnat_pool
!= -1);
2287 /* Check that we aren't violating the associated restriction. */
2288 if (!(Nkind (gnat_node
) == N_Allocator
&& Comes_From_Source (gnat_node
)))
2289 Check_No_Implicit_Heap_Alloc (gnat_node
);
2291 return maybe_wrap_malloc (gnu_size
, gnu_type
, gnat_node
);
2295 /* Build a GCC tree that corresponds to allocating an object of TYPE whose
2296 initial value is INIT, if INIT is nonzero. Convert the expression to
2297 RESULT_TYPE, which must be some pointer type, and return the result.
2299 GNAT_PROC and GNAT_POOL optionally give the procedure to call and
2300 the storage pool to use. GNAT_NODE is used to provide an error
2301 location for restriction violation messages. If IGNORE_INIT_TYPE is
2302 true, ignore the type of INIT for the purpose of determining the size;
2303 this will cause the maximum size to be allocated if TYPE is of
2304 self-referential size. */
2307 build_allocator (tree type
, tree init
, tree result_type
, Entity_Id gnat_proc
,
2308 Entity_Id gnat_pool
, Node_Id gnat_node
, bool ignore_init_type
)
2310 tree size
, storage
, storage_deref
, storage_init
;
2312 /* If the initializer, if present, is a NULL_EXPR, just return a new one. */
2313 if (init
&& TREE_CODE (init
) == NULL_EXPR
)
2314 return build1 (NULL_EXPR
, result_type
, TREE_OPERAND (init
, 0));
2316 /* If the initializer, if present, is a COND_EXPR, deal with each branch. */
2317 else if (init
&& TREE_CODE (init
) == COND_EXPR
)
2318 return build3 (COND_EXPR
, result_type
, TREE_OPERAND (init
, 0),
2319 build_allocator (type
, TREE_OPERAND (init
, 1), result_type
,
2320 gnat_proc
, gnat_pool
, gnat_node
,
2322 build_allocator (type
, TREE_OPERAND (init
, 2), result_type
,
2323 gnat_proc
, gnat_pool
, gnat_node
,
2326 /* If RESULT_TYPE is a fat or thin pointer, set SIZE to be the sum of the
2327 sizes of the object and its template. Allocate the whole thing and
2328 fill in the parts that are known. */
2329 else if (TYPE_IS_FAT_OR_THIN_POINTER_P (result_type
))
2332 = build_unc_object_type_from_ptr (result_type
, type
,
2333 get_identifier ("ALLOC"), false);
2334 tree template_type
= TREE_TYPE (TYPE_FIELDS (storage_type
));
2335 tree storage_ptr_type
= build_pointer_type (storage_type
);
2337 size
= SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (storage_type
),
2340 /* If the size overflows, pass -1 so Storage_Error will be raised. */
2341 if (TREE_CODE (size
) == INTEGER_CST
&& !valid_constant_size_p (size
))
2342 size
= size_int (-1);
2344 storage
= build_call_alloc_dealloc (NULL_TREE
, size
, storage_type
,
2345 gnat_proc
, gnat_pool
, gnat_node
);
2346 storage
= convert (storage_ptr_type
, gnat_protect_expr (storage
));
2347 storage_deref
= build_unary_op (INDIRECT_REF
, NULL_TREE
, storage
);
2348 TREE_THIS_NOTRAP (storage_deref
) = 1;
2350 /* If there is an initializing expression, then make a constructor for
2351 the entire object including the bounds and copy it into the object.
2352 If there is no initializing expression, just set the bounds. */
2355 vec
<constructor_elt
, va_gc
> *v
;
2358 CONSTRUCTOR_APPEND_ELT (v
, TYPE_FIELDS (storage_type
),
2359 build_template (template_type
, type
, init
));
2360 CONSTRUCTOR_APPEND_ELT (v
, DECL_CHAIN (TYPE_FIELDS (storage_type
)),
2363 = build_binary_op (INIT_EXPR
, NULL_TREE
, storage_deref
,
2364 gnat_build_constructor (storage_type
, v
));
2368 = build_binary_op (INIT_EXPR
, NULL_TREE
,
2369 build_component_ref (storage_deref
, NULL_TREE
,
2370 TYPE_FIELDS (storage_type
),
2372 build_template (template_type
, type
, NULL_TREE
));
2374 return build2 (COMPOUND_EXPR
, result_type
,
2375 storage_init
, convert (result_type
, storage
));
2378 size
= TYPE_SIZE_UNIT (type
);
2380 /* If we have an initializing expression, see if its size is simpler
2381 than the size from the type. */
2382 if (!ignore_init_type
&& init
&& TYPE_SIZE_UNIT (TREE_TYPE (init
))
2383 && (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (init
))) == INTEGER_CST
2384 || CONTAINS_PLACEHOLDER_P (size
)))
2385 size
= TYPE_SIZE_UNIT (TREE_TYPE (init
));
2387 /* If the size is still self-referential, reference the initializing
2388 expression, if it is present. If not, this must have been a
2389 call to allocate a library-level object, in which case we use
2390 the maximum size. */
2391 if (CONTAINS_PLACEHOLDER_P (size
))
2393 if (!ignore_init_type
&& init
)
2394 size
= substitute_placeholder_in_expr (size
, init
);
2396 size
= max_size (size
, true);
2399 /* If the size overflows, pass -1 so Storage_Error will be raised. */
2400 if (TREE_CODE (size
) == INTEGER_CST
&& !valid_constant_size_p (size
))
2401 size
= size_int (-1);
2403 storage
= convert (result_type
,
2404 build_call_alloc_dealloc (NULL_TREE
, size
, type
,
2405 gnat_proc
, gnat_pool
,
2408 /* If we have an initial value, protect the new address, assign the value
2409 and return the address with a COMPOUND_EXPR. */
2412 storage
= gnat_protect_expr (storage
);
2413 storage_deref
= build_unary_op (INDIRECT_REF
, NULL_TREE
, storage
);
2414 TREE_THIS_NOTRAP (storage_deref
) = 1;
2416 = build_binary_op (INIT_EXPR
, NULL_TREE
, storage_deref
, init
);
2417 return build2 (COMPOUND_EXPR
, result_type
, storage_init
, storage
);
2423 /* Indicate that we need to take the address of T and that it therefore
2424 should not be allocated in a register. Returns true if successful. */
2427 gnat_mark_addressable (tree t
)
2430 switch (TREE_CODE (t
))
2435 case ARRAY_RANGE_REF
:
2438 case VIEW_CONVERT_EXPR
:
2439 case NON_LVALUE_EXPR
:
2441 t
= TREE_OPERAND (t
, 0);
2445 t
= TREE_OPERAND (t
, 1);
2449 TREE_ADDRESSABLE (t
) = 1;
2455 TREE_ADDRESSABLE (t
) = 1;
2459 TREE_ADDRESSABLE (t
) = 1;
2463 return DECL_CONST_CORRESPONDING_VAR (t
)
2464 && gnat_mark_addressable (DECL_CONST_CORRESPONDING_VAR (t
));
2471 /* Save EXP for later use or reuse. This is equivalent to save_expr in tree.c
2472 but we know how to handle our own nodes. */
2475 gnat_save_expr (tree exp
)
2477 tree type
= TREE_TYPE (exp
);
2478 enum tree_code code
= TREE_CODE (exp
);
2480 if (TREE_CONSTANT (exp
) || code
== SAVE_EXPR
|| code
== NULL_EXPR
)
2483 if (code
== UNCONSTRAINED_ARRAY_REF
)
2485 tree t
= build1 (code
, type
, gnat_save_expr (TREE_OPERAND (exp
, 0)));
2486 TREE_READONLY (t
) = TYPE_READONLY (type
);
2490 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2491 This may be more efficient, but will also allow us to more easily find
2492 the match for the PLACEHOLDER_EXPR. */
2493 if (code
== COMPONENT_REF
2494 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp
, 0))))
2495 return build3 (code
, type
, gnat_save_expr (TREE_OPERAND (exp
, 0)),
2496 TREE_OPERAND (exp
, 1), TREE_OPERAND (exp
, 2));
2498 return save_expr (exp
);
2501 /* Protect EXP for immediate reuse. This is a variant of gnat_save_expr that
2502 is optimized under the assumption that EXP's value doesn't change before
2503 its subsequent reuse(s) except through its potential reevaluation. */
2506 gnat_protect_expr (tree exp
)
2508 tree type
= TREE_TYPE (exp
);
2509 enum tree_code code
= TREE_CODE (exp
);
2511 if (TREE_CONSTANT (exp
) || code
== SAVE_EXPR
|| code
== NULL_EXPR
)
2514 /* If EXP has no side effects, we theoretically don't need to do anything.
2515 However, we may be recursively passed more and more complex expressions
2516 involving checks which will be reused multiple times and eventually be
2517 unshared for gimplification; in order to avoid a complexity explosion
2518 at that point, we protect any expressions more complex than a simple
2519 arithmetic expression. */
2520 if (!TREE_SIDE_EFFECTS (exp
))
2522 tree inner
= skip_simple_arithmetic (exp
);
2523 if (!EXPR_P (inner
) || REFERENCE_CLASS_P (inner
))
2527 /* If this is a conversion, protect what's inside the conversion. */
2528 if (code
== NON_LVALUE_EXPR
2529 || CONVERT_EXPR_CODE_P (code
)
2530 || code
== VIEW_CONVERT_EXPR
)
2531 return build1 (code
, type
, gnat_protect_expr (TREE_OPERAND (exp
, 0)));
2533 /* If we're indirectly referencing something, we only need to protect the
2534 address since the data itself can't change in these situations. */
2535 if (code
== INDIRECT_REF
|| code
== UNCONSTRAINED_ARRAY_REF
)
2537 tree t
= build1 (code
, type
, gnat_protect_expr (TREE_OPERAND (exp
, 0)));
2538 TREE_READONLY (t
) = TYPE_READONLY (type
);
2542 /* If this is a COMPONENT_REF of a fat pointer, save the entire fat pointer.
2543 This may be more efficient, but will also allow us to more easily find
2544 the match for the PLACEHOLDER_EXPR. */
2545 if (code
== COMPONENT_REF
2546 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (exp
, 0))))
2547 return build3 (code
, type
, gnat_protect_expr (TREE_OPERAND (exp
, 0)),
2548 TREE_OPERAND (exp
, 1), TREE_OPERAND (exp
, 2));
2550 /* If this is a fat pointer or something that can be placed in a register,
2551 just make a SAVE_EXPR. Likewise for a CALL_EXPR as large objects are
2552 returned via invisible reference in most ABIs so the temporary will
2553 directly be filled by the callee. */
2554 if (TYPE_IS_FAT_POINTER_P (type
)
2555 || TYPE_MODE (type
) != BLKmode
2556 || code
== CALL_EXPR
)
2557 return save_expr (exp
);
2559 /* Otherwise reference, protect the address and dereference. */
2561 build_unary_op (INDIRECT_REF
, type
,
2562 save_expr (build_unary_op (ADDR_EXPR
,
2563 build_reference_type (type
),
2567 /* This is equivalent to stabilize_reference_1 in tree.c but we take an extra
2568 argument to force evaluation of everything. */
2571 gnat_stabilize_reference_1 (tree e
, bool force
)
2573 enum tree_code code
= TREE_CODE (e
);
2574 tree type
= TREE_TYPE (e
);
2577 /* We cannot ignore const expressions because it might be a reference
2578 to a const array but whose index contains side-effects. But we can
2579 ignore things that are actual constant or that already have been
2580 handled by this function. */
2581 if (TREE_CONSTANT (e
) || code
== SAVE_EXPR
)
2584 switch (TREE_CODE_CLASS (code
))
2586 case tcc_exceptional
:
2587 case tcc_declaration
:
2588 case tcc_comparison
:
2589 case tcc_expression
:
2592 /* If this is a COMPONENT_REF of a fat pointer, save the entire
2593 fat pointer. This may be more efficient, but will also allow
2594 us to more easily find the match for the PLACEHOLDER_EXPR. */
2595 if (code
== COMPONENT_REF
2596 && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (e
, 0))))
2598 = build3 (code
, type
,
2599 gnat_stabilize_reference_1 (TREE_OPERAND (e
, 0), force
),
2600 TREE_OPERAND (e
, 1), TREE_OPERAND (e
, 2));
2601 /* If the expression has side-effects, then encase it in a SAVE_EXPR
2602 so that it will only be evaluated once. */
2603 /* The tcc_reference and tcc_comparison classes could be handled as
2604 below, but it is generally faster to only evaluate them once. */
2605 else if (TREE_SIDE_EFFECTS (e
) || force
)
2606 return save_expr (e
);
2612 /* Recursively stabilize each operand. */
2614 = build2 (code
, type
,
2615 gnat_stabilize_reference_1 (TREE_OPERAND (e
, 0), force
),
2616 gnat_stabilize_reference_1 (TREE_OPERAND (e
, 1), force
));
2620 /* Recursively stabilize each operand. */
2622 = build1 (code
, type
,
2623 gnat_stabilize_reference_1 (TREE_OPERAND (e
, 0), force
));
2630 /* See similar handling in gnat_stabilize_reference. */
2631 TREE_READONLY (result
) = TREE_READONLY (e
);
2632 TREE_SIDE_EFFECTS (result
) |= TREE_SIDE_EFFECTS (e
);
2633 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (e
);
2635 if (code
== INDIRECT_REF
2636 || code
== UNCONSTRAINED_ARRAY_REF
2637 || code
== ARRAY_REF
2638 || code
== ARRAY_RANGE_REF
)
2639 TREE_THIS_NOTRAP (result
) = TREE_THIS_NOTRAP (e
);
2644 /* This is equivalent to stabilize_reference in tree.c but we know how to
2645 handle our own nodes and we take extra arguments. FORCE says whether to
2646 force evaluation of everything. We set SUCCESS to true unless we walk
2647 through something we don't know how to stabilize. */
2650 gnat_stabilize_reference (tree ref
, bool force
, bool *success
)
2652 tree type
= TREE_TYPE (ref
);
2653 enum tree_code code
= TREE_CODE (ref
);
2656 /* Assume we'll success unless proven otherwise. */
2666 /* No action is needed in this case. */
2672 case FIX_TRUNC_EXPR
:
2673 case VIEW_CONVERT_EXPR
:
2675 = build1 (code
, type
,
2676 gnat_stabilize_reference (TREE_OPERAND (ref
, 0), force
,
2681 case UNCONSTRAINED_ARRAY_REF
:
2682 result
= build1 (code
, type
,
2683 gnat_stabilize_reference_1 (TREE_OPERAND (ref
, 0),
2688 result
= build3 (COMPONENT_REF
, type
,
2689 gnat_stabilize_reference (TREE_OPERAND (ref
, 0), force
,
2691 TREE_OPERAND (ref
, 1), NULL_TREE
);
2695 result
= build3 (BIT_FIELD_REF
, type
,
2696 gnat_stabilize_reference (TREE_OPERAND (ref
, 0), force
,
2698 TREE_OPERAND (ref
, 1), TREE_OPERAND (ref
, 2));
2702 case ARRAY_RANGE_REF
:
2703 result
= build4 (code
, type
,
2704 gnat_stabilize_reference (TREE_OPERAND (ref
, 0), force
,
2706 gnat_stabilize_reference_1 (TREE_OPERAND (ref
, 1),
2708 NULL_TREE
, NULL_TREE
);
2712 result
= gnat_stabilize_reference_1 (ref
, force
);
2716 result
= build2 (COMPOUND_EXPR
, type
,
2717 gnat_stabilize_reference (TREE_OPERAND (ref
, 0), force
,
2719 gnat_stabilize_reference (TREE_OPERAND (ref
, 1), force
,
2724 /* Constructors with 1 element are used extensively to formally
2725 convert objects to special wrapping types. */
2726 if (TREE_CODE (type
) == RECORD_TYPE
2727 && vec_safe_length (CONSTRUCTOR_ELTS (ref
)) == 1)
2729 tree index
= (*CONSTRUCTOR_ELTS (ref
))[0].index
;
2730 tree value
= (*CONSTRUCTOR_ELTS (ref
))[0].value
;
2732 = build_constructor_single (type
, index
,
2733 gnat_stabilize_reference_1 (value
,
2745 ref
= error_mark_node
;
2747 /* ... fall through to failure ... */
2749 /* If arg isn't a kind of lvalue we recognize, make no change.
2750 Caller should recognize the error for an invalid lvalue. */
2757 /* TREE_THIS_VOLATILE and TREE_SIDE_EFFECTS set on the initial expression
2758 may not be sustained across some paths, such as the way via build1 for
2759 INDIRECT_REF. We reset those flags here in the general case, which is
2760 consistent with the GCC version of this routine.
2762 Special care should be taken regarding TREE_SIDE_EFFECTS, because some
2763 paths introduce side-effects where there was none initially (e.g. if a
2764 SAVE_EXPR is built) and we also want to keep track of that. */
2765 TREE_READONLY (result
) = TREE_READONLY (ref
);
2766 TREE_SIDE_EFFECTS (result
) |= TREE_SIDE_EFFECTS (ref
);
2767 TREE_THIS_VOLATILE (result
) = TREE_THIS_VOLATILE (ref
);
2769 if (code
== INDIRECT_REF
2770 || code
== UNCONSTRAINED_ARRAY_REF
2771 || code
== ARRAY_REF
2772 || code
== ARRAY_RANGE_REF
)
2773 TREE_THIS_NOTRAP (result
) = TREE_THIS_NOTRAP (ref
);
2778 /* If EXPR is an expression that is invariant in the current function, in the
2779 sense that it can be evaluated anywhere in the function and any number of
2780 times, return EXPR or an equivalent expression. Otherwise return NULL. */
2783 gnat_invariant_expr (tree expr
)
2785 tree type
= TREE_TYPE (expr
), t
;
2787 expr
= remove_conversions (expr
, false);
2789 while ((TREE_CODE (expr
) == CONST_DECL
2790 || (TREE_CODE (expr
) == VAR_DECL
&& TREE_READONLY (expr
)))
2791 && decl_function_context (expr
) == current_function_decl
2792 && DECL_INITIAL (expr
))
2794 expr
= DECL_INITIAL (expr
);
2795 /* Look into CONSTRUCTORs built to initialize padded types. */
2796 if (TYPE_IS_PADDING_P (TREE_TYPE (expr
)))
2797 expr
= convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (expr
))), expr
);
2798 expr
= remove_conversions (expr
, false);
2801 if (TREE_CONSTANT (expr
))
2802 return fold_convert (type
, expr
);
2808 switch (TREE_CODE (t
))
2811 if (TREE_OPERAND (t
, 2) != NULL_TREE
)
2816 case ARRAY_RANGE_REF
:
2817 if (!TREE_CONSTANT (TREE_OPERAND (t
, 1))
2818 || TREE_OPERAND (t
, 2) != NULL_TREE
2819 || TREE_OPERAND (t
, 3) != NULL_TREE
)
2824 case VIEW_CONVERT_EXPR
:
2830 if (!TREE_READONLY (t
)
2831 || TREE_SIDE_EFFECTS (t
)
2832 || !TREE_THIS_NOTRAP (t
))
2840 t
= TREE_OPERAND (t
, 0);
2844 if (TREE_SIDE_EFFECTS (t
))
2847 if (TREE_CODE (t
) == CONST_DECL
2848 && (DECL_EXTERNAL (t
)
2849 || decl_function_context (t
) != current_function_decl
))
2850 return fold_convert (type
, expr
);
2852 if (!TREE_READONLY (t
))
2855 if (TREE_CODE (t
) == PARM_DECL
)
2856 return fold_convert (type
, expr
);
2858 if (TREE_CODE (t
) == VAR_DECL
2859 && (DECL_EXTERNAL (t
)
2860 || decl_function_context (t
) != current_function_decl
))
2861 return fold_convert (type
, expr
);