1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2009, 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 ****************************************************************************/
26 /* We have attribute handlers using C specific format specifiers in warning
27 messages. Make sure they are properly recognized. */
28 #define GCC_DIAG_STYLE __gcc_cdiag__
32 #include "coretypes.h"
45 #include "tree-inline.h"
46 #include "tree-iterator.h"
48 #include "tree-dump.h"
49 #include "pointer-set.h"
50 #include "langhooks.h"
67 #ifndef MAX_FIXED_MODE_SIZE
68 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
71 #ifndef MAX_BITS_PER_WORD
72 #define MAX_BITS_PER_WORD BITS_PER_WORD
75 /* If nonzero, pretend we are allocating at global level. */
78 /* Tree nodes for the various types and decls we create. */
79 tree gnat_std_decls[(int) ADT_LAST];
81 /* Functions to call for each of the possible raise reasons. */
82 tree gnat_raise_decls[(int) LAST_REASON_CODE + 1];
84 /* Forward declarations for handlers of attributes. */
85 static tree handle_const_attribute (tree *, tree, tree, int, bool *);
86 static tree handle_nothrow_attribute (tree *, tree, tree, int, bool *);
87 static tree handle_pure_attribute (tree *, tree, tree, int, bool *);
88 static tree handle_novops_attribute (tree *, tree, tree, int, bool *);
89 static tree handle_nonnull_attribute (tree *, tree, tree, int, bool *);
90 static tree handle_sentinel_attribute (tree *, tree, tree, int, bool *);
91 static tree handle_noreturn_attribute (tree *, tree, tree, int, bool *);
92 static tree handle_malloc_attribute (tree *, tree, tree, int, bool *);
93 static tree handle_type_generic_attribute (tree *, tree, tree, int, bool *);
95 /* Fake handler for attributes we don't properly support, typically because
96 they'd require dragging a lot of the common-c front-end circuitry. */
97 static tree fake_attribute_handler (tree *, tree, tree, int, bool *);
99 /* Table of machine-independent internal attributes for Ada. We support
100 this minimal set of attributes to accommodate the needs of builtins. */
101 const struct attribute_spec gnat_internal_attribute_table[] =
103 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
104 { "const", 0, 0, true, false, false, handle_const_attribute },
105 { "nothrow", 0, 0, true, false, false, handle_nothrow_attribute },
106 { "pure", 0, 0, true, false, false, handle_pure_attribute },
107 { "no vops", 0, 0, true, false, false, handle_novops_attribute },
108 { "nonnull", 0, -1, false, true, true, handle_nonnull_attribute },
109 { "sentinel", 0, 1, false, true, true, handle_sentinel_attribute },
110 { "noreturn", 0, 0, true, false, false, handle_noreturn_attribute },
111 { "malloc", 0, 0, true, false, false, handle_malloc_attribute },
112 { "type generic", 0, 0, false, true, true, handle_type_generic_attribute },
114 /* ??? format and format_arg are heavy and not supported, which actually
115 prevents support for stdio builtins, which we however declare as part
116 of the common builtins.def contents. */
117 { "format", 3, 3, false, true, true, fake_attribute_handler },
118 { "format_arg", 1, 1, false, true, true, fake_attribute_handler },
120 { NULL, 0, 0, false, false, false, NULL }
123 /* Associates a GNAT tree node to a GCC tree node. It is used in
124 `save_gnu_tree', `get_gnu_tree' and `present_gnu_tree'. See documentation
125 of `save_gnu_tree' for more info. */
126 static GTY((length ("max_gnat_nodes"))) tree *associate_gnat_to_gnu;
128 #define GET_GNU_TREE(GNAT_ENTITY) \
129 associate_gnat_to_gnu[(GNAT_ENTITY) - First_Node_Id]
131 #define SET_GNU_TREE(GNAT_ENTITY,VAL) \
132 associate_gnat_to_gnu[(GNAT_ENTITY) - First_Node_Id] = (VAL)
134 #define PRESENT_GNU_TREE(GNAT_ENTITY) \
135 (associate_gnat_to_gnu[(GNAT_ENTITY) - First_Node_Id] != NULL_TREE)
137 /* Associates a GNAT entity to a GCC tree node used as a dummy, if any. */
138 static GTY((length ("max_gnat_nodes"))) tree *dummy_node_table;
140 #define GET_DUMMY_NODE(GNAT_ENTITY) \
141 dummy_node_table[(GNAT_ENTITY) - First_Node_Id]
143 #define SET_DUMMY_NODE(GNAT_ENTITY,VAL) \
144 dummy_node_table[(GNAT_ENTITY) - First_Node_Id] = (VAL)
146 #define PRESENT_DUMMY_NODE(GNAT_ENTITY) \
147 (dummy_node_table[(GNAT_ENTITY) - First_Node_Id] != NULL_TREE)
149 /* This variable keeps a table for types for each precision so that we only
150 allocate each of them once. Signed and unsigned types are kept separate.
152 Note that these types are only used when fold-const requests something
153 special. Perhaps we should NOT share these types; we'll see how it
155 static GTY(()) tree signed_and_unsigned_types[2 * MAX_BITS_PER_WORD + 1][2];
157 /* Likewise for float types, but record these by mode. */
158 static GTY(()) tree float_types[NUM_MACHINE_MODES];
160 /* For each binding contour we allocate a binding_level structure to indicate
161 the binding depth. */
163 struct gnat_binding_level GTY((chain_next ("%h.chain")))
165 /* The binding level containing this one (the enclosing binding level). */
166 struct gnat_binding_level *chain;
167 /* The BLOCK node for this level. */
169 /* If nonzero, the setjmp buffer that needs to be updated for any
170 variable-sized definition within this context. */
174 /* The binding level currently in effect. */
175 static GTY(()) struct gnat_binding_level *current_binding_level;
177 /* A chain of gnat_binding_level structures awaiting reuse. */
178 static GTY((deletable)) struct gnat_binding_level *free_binding_level;
180 /* An array of global declarations. */
181 static GTY(()) VEC(tree,gc) *global_decls;
183 /* An array of builtin function declarations. */
184 static GTY(()) VEC(tree,gc) *builtin_decls;
186 /* An array of global renaming pointers. */
187 static GTY(()) VEC(tree,gc) *global_renaming_pointers;
189 /* A chain of unused BLOCK nodes. */
190 static GTY((deletable)) tree free_block_chain;
192 static tree merge_sizes (tree, tree, tree, bool, bool);
193 static tree compute_related_constant (tree, tree);
194 static tree split_plus (tree, tree *);
195 static void gnat_gimplify_function (tree);
196 static tree float_type_for_precision (int, enum machine_mode);
197 static tree convert_to_fat_pointer (tree, tree);
198 static tree convert_to_thin_pointer (tree, tree);
199 static tree make_descriptor_field (const char *,tree, tree, tree);
200 static bool potential_alignment_gap (tree, tree, tree);
202 /* Initialize the association of GNAT nodes to GCC trees. */
205 init_gnat_to_gnu (void)
207 associate_gnat_to_gnu
208 = (tree *) ggc_alloc_cleared (max_gnat_nodes * sizeof (tree));
211 /* GNAT_ENTITY is a GNAT tree node for an entity. GNU_DECL is the GCC tree
212 which is to be associated with GNAT_ENTITY. Such GCC tree node is always
213 a ..._DECL node. If NO_CHECK is true, the latter check is suppressed.
215 If GNU_DECL is zero, a previous association is to be reset. */
218 save_gnu_tree (Entity_Id gnat_entity, tree gnu_decl, bool no_check)
220 /* Check that GNAT_ENTITY is not already defined and that it is being set
221 to something which is a decl. Raise gigi 401 if not. Usually, this
222 means GNAT_ENTITY is defined twice, but occasionally is due to some
224 gcc_assert (!(gnu_decl
225 && (PRESENT_GNU_TREE (gnat_entity)
226 || (!no_check && !DECL_P (gnu_decl)))));
228 SET_GNU_TREE (gnat_entity, gnu_decl);
231 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
232 Return the ..._DECL node that was associated with it. If there is no tree
233 node associated with GNAT_ENTITY, abort.
235 In some cases, such as delayed elaboration or expressions that need to
236 be elaborated only once, GNAT_ENTITY is really not an entity. */
239 get_gnu_tree (Entity_Id gnat_entity)
241 gcc_assert (PRESENT_GNU_TREE (gnat_entity));
242 return GET_GNU_TREE (gnat_entity);
245 /* Return nonzero if a GCC tree has been associated with GNAT_ENTITY. */
248 present_gnu_tree (Entity_Id gnat_entity)
250 return PRESENT_GNU_TREE (gnat_entity);
253 /* Initialize the association of GNAT nodes to GCC trees as dummies. */
256 init_dummy_type (void)
259 = (tree *) ggc_alloc_cleared (max_gnat_nodes * sizeof (tree));
262 /* Make a dummy type corresponding to GNAT_TYPE. */
265 make_dummy_type (Entity_Id gnat_type)
267 Entity_Id gnat_underlying = Gigi_Equivalent_Type (gnat_type);
270 /* If there is an equivalent type, get its underlying type. */
271 if (Present (gnat_underlying))
272 gnat_underlying = Underlying_Type (gnat_underlying);
274 /* If there was no equivalent type (can only happen when just annotating
275 types) or underlying type, go back to the original type. */
276 if (No (gnat_underlying))
277 gnat_underlying = gnat_type;
279 /* If it there already a dummy type, use that one. Else make one. */
280 if (PRESENT_DUMMY_NODE (gnat_underlying))
281 return GET_DUMMY_NODE (gnat_underlying);
283 /* If this is a record, make a RECORD_TYPE or UNION_TYPE; else make
285 gnu_type = make_node (Is_Record_Type (gnat_underlying)
286 ? tree_code_for_record_type (gnat_underlying)
288 TYPE_NAME (gnu_type) = get_entity_name (gnat_type);
289 TYPE_DUMMY_P (gnu_type) = 1;
290 TYPE_STUB_DECL (gnu_type)
291 = create_type_stub_decl (TYPE_NAME (gnu_type), gnu_type);
292 if (AGGREGATE_TYPE_P (gnu_type))
293 TYPE_BY_REFERENCE_P (gnu_type) = Is_By_Reference_Type (gnat_type);
295 SET_DUMMY_NODE (gnat_underlying, gnu_type);
300 /* Return nonzero if we are currently in the global binding level. */
303 global_bindings_p (void)
305 return ((force_global || !current_function_decl) ? -1 : 0);
308 /* Enter a new binding level. */
313 struct gnat_binding_level *newlevel = NULL;
315 /* Reuse a struct for this binding level, if there is one. */
316 if (free_binding_level)
318 newlevel = free_binding_level;
319 free_binding_level = free_binding_level->chain;
323 = (struct gnat_binding_level *)
324 ggc_alloc (sizeof (struct gnat_binding_level));
326 /* Use a free BLOCK, if any; otherwise, allocate one. */
327 if (free_block_chain)
329 newlevel->block = free_block_chain;
330 free_block_chain = BLOCK_CHAIN (free_block_chain);
331 BLOCK_CHAIN (newlevel->block) = NULL_TREE;
334 newlevel->block = make_node (BLOCK);
336 /* Point the BLOCK we just made to its parent. */
337 if (current_binding_level)
338 BLOCK_SUPERCONTEXT (newlevel->block) = current_binding_level->block;
340 BLOCK_VARS (newlevel->block) = BLOCK_SUBBLOCKS (newlevel->block) = NULL_TREE;
341 TREE_USED (newlevel->block) = 1;
343 /* Add this level to the front of the chain (stack) of levels that are
345 newlevel->chain = current_binding_level;
346 newlevel->jmpbuf_decl = NULL_TREE;
347 current_binding_level = newlevel;
350 /* Set SUPERCONTEXT of the BLOCK for the current binding level to FNDECL
351 and point FNDECL to this BLOCK. */
354 set_current_block_context (tree fndecl)
356 BLOCK_SUPERCONTEXT (current_binding_level->block) = fndecl;
357 DECL_INITIAL (fndecl) = current_binding_level->block;
360 /* Set the jmpbuf_decl for the current binding level to DECL. */
363 set_block_jmpbuf_decl (tree decl)
365 current_binding_level->jmpbuf_decl = decl;
368 /* Get the jmpbuf_decl, if any, for the current binding level. */
371 get_block_jmpbuf_decl ()
373 return current_binding_level->jmpbuf_decl;
376 /* Exit a binding level. Set any BLOCK into the current code group. */
381 struct gnat_binding_level *level = current_binding_level;
382 tree block = level->block;
384 BLOCK_VARS (block) = nreverse (BLOCK_VARS (block));
385 BLOCK_SUBBLOCKS (block) = nreverse (BLOCK_SUBBLOCKS (block));
387 /* If this is a function-level BLOCK don't do anything. Otherwise, if there
388 are no variables free the block and merge its subblocks into those of its
389 parent block. Otherwise, add it to the list of its parent. */
390 if (TREE_CODE (BLOCK_SUPERCONTEXT (block)) == FUNCTION_DECL)
392 else if (BLOCK_VARS (block) == NULL_TREE)
394 BLOCK_SUBBLOCKS (level->chain->block)
395 = chainon (BLOCK_SUBBLOCKS (block),
396 BLOCK_SUBBLOCKS (level->chain->block));
397 BLOCK_CHAIN (block) = free_block_chain;
398 free_block_chain = block;
402 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (level->chain->block);
403 BLOCK_SUBBLOCKS (level->chain->block) = block;
404 TREE_USED (block) = 1;
405 set_block_for_group (block);
408 /* Free this binding structure. */
409 current_binding_level = level->chain;
410 level->chain = free_binding_level;
411 free_binding_level = level;
415 /* Records a ..._DECL node DECL as belonging to the current lexical scope
416 and uses GNAT_NODE for location information and propagating flags. */
419 gnat_pushdecl (tree decl, Node_Id gnat_node)
421 /* If this decl is public external or at toplevel, there is no context.
422 But PARM_DECLs always go in the level of its function. */
423 if (TREE_CODE (decl) != PARM_DECL
424 && ((DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
425 || global_bindings_p ()))
426 DECL_CONTEXT (decl) = 0;
429 DECL_CONTEXT (decl) = current_function_decl;
431 /* Functions imported in another function are not really nested. */
432 if (TREE_CODE (decl) == FUNCTION_DECL && TREE_PUBLIC (decl))
433 DECL_NO_STATIC_CHAIN (decl) = 1;
436 TREE_NO_WARNING (decl) = (gnat_node == Empty || Warnings_Off (gnat_node));
438 /* Set the location of DECL and emit a declaration for it. */
439 if (Present (gnat_node))
440 Sloc_to_locus (Sloc (gnat_node), &DECL_SOURCE_LOCATION (decl));
441 add_decl_expr (decl, gnat_node);
443 /* Put the declaration on the list. The list of declarations is in reverse
444 order. The list will be reversed later. Put global variables in the
445 globals list and builtin functions in a dedicated list to speed up
446 further lookups. Don't put TYPE_DECLs for UNCONSTRAINED_ARRAY_TYPE into
447 the list, as they will cause trouble with the debugger and aren't needed
449 if (TREE_CODE (decl) != TYPE_DECL
450 || TREE_CODE (TREE_TYPE (decl)) != UNCONSTRAINED_ARRAY_TYPE)
452 if (global_bindings_p ())
454 VEC_safe_push (tree, gc, global_decls, decl);
456 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
457 VEC_safe_push (tree, gc, builtin_decls, decl);
461 TREE_CHAIN (decl) = BLOCK_VARS (current_binding_level->block);
462 BLOCK_VARS (current_binding_level->block) = decl;
466 /* For the declaration of a type, set its name if it either is not already
467 set or if the previous type name was not derived from a source name.
468 We'd rather have the type named with a real name and all the pointer
469 types to the same object have the same POINTER_TYPE node. Code in the
470 equivalent function of c-decl.c makes a copy of the type node here, but
471 that may cause us trouble with incomplete types. We make an exception
472 for fat pointer types because the compiler automatically builds them
473 for unconstrained array types and the debugger uses them to represent
474 both these and pointers to these. */
475 if (TREE_CODE (decl) == TYPE_DECL && DECL_NAME (decl))
477 tree t = TREE_TYPE (decl);
479 if (!(TYPE_NAME (t) && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL))
481 else if (TYPE_FAT_POINTER_P (t))
483 tree tt = build_variant_type_copy (t);
484 TYPE_NAME (tt) = decl;
485 TREE_USED (tt) = TREE_USED (t);
486 TREE_TYPE (decl) = tt;
487 DECL_ORIGINAL_TYPE (decl) = t;
490 else if (DECL_ARTIFICIAL (TYPE_NAME (t)) && !DECL_ARTIFICIAL (decl))
495 /* Propagate the name to all the variants. This is needed for
496 the type qualifiers machinery to work properly. */
498 for (t = TYPE_MAIN_VARIANT (t); t; t = TYPE_NEXT_VARIANT (t))
499 TYPE_NAME (t) = decl;
503 /* Do little here. Set up the standard declarations later after the
504 front end has been run. */
507 gnat_init_decl_processing (void)
509 /* Make the binding_level structure for global names. */
510 current_function_decl = 0;
511 current_binding_level = 0;
512 free_binding_level = 0;
515 build_common_tree_nodes (true, true);
517 /* In Ada, we use a signed type for SIZETYPE. Use the signed type
518 corresponding to the width of Pmode. In most cases when ptr_mode
519 and Pmode differ, C will use the width of ptr_mode for SIZETYPE.
520 But we get far better code using the width of Pmode. */
521 size_type_node = gnat_type_for_mode (Pmode, 0);
522 set_sizetype (size_type_node);
524 /* In Ada, we use an unsigned 8-bit type for the default boolean type. */
525 boolean_type_node = make_node (BOOLEAN_TYPE);
526 TYPE_PRECISION (boolean_type_node) = 1;
527 fixup_unsigned_type (boolean_type_node);
528 TYPE_RM_SIZE (boolean_type_node) = bitsize_int (1);
530 build_common_tree_nodes_2 (0);
532 ptr_void_type_node = build_pointer_type (void_type_node);
535 /* Record TYPE as a builtin type for Ada. NAME is the name of the type. */
538 record_builtin_type (const char *name, tree type)
540 tree type_decl = build_decl (TYPE_DECL, get_identifier (name), type);
542 gnat_pushdecl (type_decl, Empty);
544 if (debug_hooks->type_decl)
545 debug_hooks->type_decl (type_decl, false);
548 /* Given a record type RECORD_TYPE and a chain of FIELD_DECL nodes FIELDLIST,
549 finish constructing the record or union type. If REP_LEVEL is zero, this
550 record has no representation clause and so will be entirely laid out here.
551 If REP_LEVEL is one, this record has a representation clause and has been
552 laid out already; only set the sizes and alignment. If REP_LEVEL is two,
553 this record is derived from a parent record and thus inherits its layout;
554 only make a pass on the fields to finalize them. If DO_NOT_FINALIZE is
555 true, the record type is expected to be modified afterwards so it will
556 not be sent to the back-end for finalization. */
559 finish_record_type (tree record_type, tree fieldlist, int rep_level,
560 bool do_not_finalize)
562 enum tree_code code = TREE_CODE (record_type);
563 tree name = TYPE_NAME (record_type);
564 tree ada_size = bitsize_zero_node;
565 tree size = bitsize_zero_node;
566 bool had_size = TYPE_SIZE (record_type) != 0;
567 bool had_size_unit = TYPE_SIZE_UNIT (record_type) != 0;
568 bool had_align = TYPE_ALIGN (record_type) != 0;
571 TYPE_FIELDS (record_type) = fieldlist;
573 /* Always attach the TYPE_STUB_DECL for a record type. It is required to
574 generate debug info and have a parallel type. */
575 if (name && TREE_CODE (name) == TYPE_DECL)
576 name = DECL_NAME (name);
577 TYPE_STUB_DECL (record_type) = create_type_stub_decl (name, record_type);
579 /* Globally initialize the record first. If this is a rep'ed record,
580 that just means some initializations; otherwise, layout the record. */
583 TYPE_ALIGN (record_type) = MAX (BITS_PER_UNIT, TYPE_ALIGN (record_type));
584 SET_TYPE_MODE (record_type, BLKmode);
587 TYPE_SIZE_UNIT (record_type) = size_zero_node;
589 TYPE_SIZE (record_type) = bitsize_zero_node;
591 /* For all-repped records with a size specified, lay the QUAL_UNION_TYPE
592 out just like a UNION_TYPE, since the size will be fixed. */
593 else if (code == QUAL_UNION_TYPE)
598 /* Ensure there isn't a size already set. There can be in an error
599 case where there is a rep clause but all fields have errors and
600 no longer have a position. */
601 TYPE_SIZE (record_type) = 0;
602 layout_type (record_type);
605 /* At this point, the position and size of each field is known. It was
606 either set before entry by a rep clause, or by laying out the type above.
608 We now run a pass over the fields (in reverse order for QUAL_UNION_TYPEs)
609 to compute the Ada size; the GCC size and alignment (for rep'ed records
610 that are not padding types); and the mode (for rep'ed records). We also
611 clear the DECL_BIT_FIELD indication for the cases we know have not been
612 handled yet, and adjust DECL_NONADDRESSABLE_P accordingly. */
614 if (code == QUAL_UNION_TYPE)
615 fieldlist = nreverse (fieldlist);
617 for (field = fieldlist; field; field = TREE_CHAIN (field))
619 tree type = TREE_TYPE (field);
620 tree pos = bit_position (field);
621 tree this_size = DECL_SIZE (field);
624 if ((TREE_CODE (type) == RECORD_TYPE
625 || TREE_CODE (type) == UNION_TYPE
626 || TREE_CODE (type) == QUAL_UNION_TYPE)
627 && !TYPE_IS_FAT_POINTER_P (type)
628 && !TYPE_CONTAINS_TEMPLATE_P (type)
629 && TYPE_ADA_SIZE (type))
630 this_ada_size = TYPE_ADA_SIZE (type);
632 this_ada_size = this_size;
634 /* Clear DECL_BIT_FIELD for the cases layout_decl does not handle. */
635 if (DECL_BIT_FIELD (field)
636 && operand_equal_p (this_size, TYPE_SIZE (type), 0))
638 unsigned int align = TYPE_ALIGN (type);
640 /* In the general case, type alignment is required. */
641 if (value_factor_p (pos, align))
643 /* The enclosing record type must be sufficiently aligned.
644 Otherwise, if no alignment was specified for it and it
645 has been laid out already, bump its alignment to the
646 desired one if this is compatible with its size. */
647 if (TYPE_ALIGN (record_type) >= align)
649 DECL_ALIGN (field) = MAX (DECL_ALIGN (field), align);
650 DECL_BIT_FIELD (field) = 0;
654 && value_factor_p (TYPE_SIZE (record_type), align))
656 TYPE_ALIGN (record_type) = align;
657 DECL_ALIGN (field) = MAX (DECL_ALIGN (field), align);
658 DECL_BIT_FIELD (field) = 0;
662 /* In the non-strict alignment case, only byte alignment is. */
663 if (!STRICT_ALIGNMENT
664 && DECL_BIT_FIELD (field)
665 && value_factor_p (pos, BITS_PER_UNIT))
666 DECL_BIT_FIELD (field) = 0;
669 /* If we still have DECL_BIT_FIELD set at this point, we know the field
670 is technically not addressable. Except that it can actually be
671 addressed if the field is BLKmode and happens to be properly
673 DECL_NONADDRESSABLE_P (field)
674 |= DECL_BIT_FIELD (field) && DECL_MODE (field) != BLKmode;
676 /* A type must be as aligned as its most aligned field that is not
677 a bit-field. But this is already enforced by layout_type. */
678 if (rep_level > 0 && !DECL_BIT_FIELD (field))
679 TYPE_ALIGN (record_type)
680 = MAX (TYPE_ALIGN (record_type), DECL_ALIGN (field));
685 ada_size = size_binop (MAX_EXPR, ada_size, this_ada_size);
686 size = size_binop (MAX_EXPR, size, this_size);
689 case QUAL_UNION_TYPE:
691 = fold_build3 (COND_EXPR, bitsizetype, DECL_QUALIFIER (field),
692 this_ada_size, ada_size);
693 size = fold_build3 (COND_EXPR, bitsizetype, DECL_QUALIFIER (field),
698 /* Since we know here that all fields are sorted in order of
699 increasing bit position, the size of the record is one
700 higher than the ending bit of the last field processed
701 unless we have a rep clause, since in that case we might
702 have a field outside a QUAL_UNION_TYPE that has a higher ending
703 position. So use a MAX in that case. Also, if this field is a
704 QUAL_UNION_TYPE, we need to take into account the previous size in
705 the case of empty variants. */
707 = merge_sizes (ada_size, pos, this_ada_size,
708 TREE_CODE (type) == QUAL_UNION_TYPE, rep_level > 0);
710 = merge_sizes (size, pos, this_size,
711 TREE_CODE (type) == QUAL_UNION_TYPE, rep_level > 0);
719 if (code == QUAL_UNION_TYPE)
720 nreverse (fieldlist);
722 /* If the type is discriminated, it can be used to access all its
723 constrained subtypes, so force structural equality checks. */
724 if (CONTAINS_PLACEHOLDER_P (size))
725 SET_TYPE_STRUCTURAL_EQUALITY (record_type);
729 /* If this is a padding record, we never want to make the size smaller
730 than what was specified in it, if any. */
731 if (TREE_CODE (record_type) == RECORD_TYPE
732 && TYPE_IS_PADDING_P (record_type) && TYPE_SIZE (record_type))
733 size = TYPE_SIZE (record_type);
735 /* Now set any of the values we've just computed that apply. */
736 if (!TYPE_IS_FAT_POINTER_P (record_type)
737 && !TYPE_CONTAINS_TEMPLATE_P (record_type))
738 SET_TYPE_ADA_SIZE (record_type, ada_size);
742 tree size_unit = had_size_unit
743 ? TYPE_SIZE_UNIT (record_type)
745 size_binop (CEIL_DIV_EXPR, size,
747 unsigned int align = TYPE_ALIGN (record_type);
749 TYPE_SIZE (record_type) = variable_size (round_up (size, align));
750 TYPE_SIZE_UNIT (record_type)
751 = variable_size (round_up (size_unit, align / BITS_PER_UNIT));
753 compute_record_mode (record_type);
757 if (!do_not_finalize)
758 rest_of_record_type_compilation (record_type);
761 /* Wrap up compilation of RECORD_TYPE, i.e. most notably output all
762 the debug information associated with it. It need not be invoked
763 directly in most cases since finish_record_type takes care of doing
764 so, unless explicitly requested not to through DO_NOT_FINALIZE. */
767 rest_of_record_type_compilation (tree record_type)
769 tree fieldlist = TYPE_FIELDS (record_type);
771 enum tree_code code = TREE_CODE (record_type);
772 bool var_size = false;
774 for (field = fieldlist; field; field = TREE_CHAIN (field))
776 /* We need to make an XVE/XVU record if any field has variable size,
777 whether or not the record does. For example, if we have a union,
778 it may be that all fields, rounded up to the alignment, have the
779 same size, in which case we'll use that size. But the debug
780 output routines (except Dwarf2) won't be able to output the fields,
781 so we need to make the special record. */
782 if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST
783 /* If a field has a non-constant qualifier, the record will have
784 variable size too. */
785 || (code == QUAL_UNION_TYPE
786 && TREE_CODE (DECL_QUALIFIER (field)) != INTEGER_CST))
793 /* If this record is of variable size, rename it so that the
794 debugger knows it is and make a new, parallel, record
795 that tells the debugger how the record is laid out. See
796 exp_dbug.ads. But don't do this for records that are padding
797 since they confuse GDB. */
799 && !(TREE_CODE (record_type) == RECORD_TYPE
800 && TYPE_IS_PADDING_P (record_type)))
803 = make_node (TREE_CODE (record_type) == QUAL_UNION_TYPE
804 ? UNION_TYPE : TREE_CODE (record_type));
805 tree orig_name = TYPE_NAME (record_type);
807 = (TREE_CODE (orig_name) == TYPE_DECL ? DECL_NAME (orig_name)
810 = concat_id_with_name (orig_id,
811 TREE_CODE (record_type) == QUAL_UNION_TYPE
813 tree last_pos = bitsize_zero_node;
815 tree prev_old_field = 0;
817 TYPE_NAME (new_record_type) = new_id;
818 TYPE_ALIGN (new_record_type) = BIGGEST_ALIGNMENT;
819 TYPE_STUB_DECL (new_record_type)
820 = create_type_stub_decl (new_id, new_record_type);
821 DECL_IGNORED_P (TYPE_STUB_DECL (new_record_type))
822 = DECL_IGNORED_P (TYPE_STUB_DECL (record_type));
823 TYPE_SIZE (new_record_type) = size_int (TYPE_ALIGN (record_type));
824 TYPE_SIZE_UNIT (new_record_type)
825 = size_int (TYPE_ALIGN (record_type) / BITS_PER_UNIT);
827 add_parallel_type (TYPE_STUB_DECL (record_type), new_record_type);
829 /* Now scan all the fields, replacing each field with a new
830 field corresponding to the new encoding. */
831 for (old_field = TYPE_FIELDS (record_type); old_field;
832 old_field = TREE_CHAIN (old_field))
834 tree field_type = TREE_TYPE (old_field);
835 tree field_name = DECL_NAME (old_field);
837 tree curpos = bit_position (old_field);
839 unsigned int align = 0;
842 /* See how the position was modified from the last position.
844 There are two basic cases we support: a value was added
845 to the last position or the last position was rounded to
846 a boundary and they something was added. Check for the
847 first case first. If not, see if there is any evidence
848 of rounding. If so, round the last position and try
851 If this is a union, the position can be taken as zero. */
853 /* Some computations depend on the shape of the position expression,
854 so strip conversions to make sure it's exposed. */
855 curpos = remove_conversions (curpos, true);
857 if (TREE_CODE (new_record_type) == UNION_TYPE)
858 pos = bitsize_zero_node, align = 0;
860 pos = compute_related_constant (curpos, last_pos);
862 if (!pos && TREE_CODE (curpos) == MULT_EXPR
863 && host_integerp (TREE_OPERAND (curpos, 1), 1))
865 tree offset = TREE_OPERAND (curpos, 0);
866 align = tree_low_cst (TREE_OPERAND (curpos, 1), 1);
868 /* An offset which is a bitwise AND with a negative power of 2
869 means an alignment corresponding to this power of 2. */
870 offset = remove_conversions (offset, true);
871 if (TREE_CODE (offset) == BIT_AND_EXPR
872 && host_integerp (TREE_OPERAND (offset, 1), 0)
873 && tree_int_cst_sgn (TREE_OPERAND (offset, 1)) < 0)
876 = - tree_low_cst (TREE_OPERAND (offset, 1), 0);
877 if (exact_log2 (pow) > 0)
881 pos = compute_related_constant (curpos,
882 round_up (last_pos, align));
884 else if (!pos && TREE_CODE (curpos) == PLUS_EXPR
885 && TREE_CODE (TREE_OPERAND (curpos, 1)) == INTEGER_CST
886 && TREE_CODE (TREE_OPERAND (curpos, 0)) == MULT_EXPR
887 && host_integerp (TREE_OPERAND
888 (TREE_OPERAND (curpos, 0), 1),
893 (TREE_OPERAND (TREE_OPERAND (curpos, 0), 1), 1);
894 pos = compute_related_constant (curpos,
895 round_up (last_pos, align));
897 else if (potential_alignment_gap (prev_old_field, old_field,
900 align = TYPE_ALIGN (field_type);
901 pos = compute_related_constant (curpos,
902 round_up (last_pos, align));
905 /* If we can't compute a position, set it to zero.
907 ??? We really should abort here, but it's too much work
908 to get this correct for all cases. */
911 pos = bitsize_zero_node;
913 /* See if this type is variable-sized and make a pointer type
914 and indicate the indirection if so. Beware that the debug
915 back-end may adjust the position computed above according
916 to the alignment of the field type, i.e. the pointer type
917 in this case, if we don't preventively counter that. */
918 if (TREE_CODE (DECL_SIZE (old_field)) != INTEGER_CST)
920 field_type = build_pointer_type (field_type);
921 if (align != 0 && TYPE_ALIGN (field_type) > align)
923 field_type = copy_node (field_type);
924 TYPE_ALIGN (field_type) = align;
929 /* Make a new field name, if necessary. */
930 if (var || align != 0)
935 sprintf (suffix, "XV%c%u", var ? 'L' : 'A',
936 align / BITS_PER_UNIT);
938 strcpy (suffix, "XVL");
940 field_name = concat_id_with_name (field_name, suffix);
943 new_field = create_field_decl (field_name, field_type,
945 DECL_SIZE (old_field), pos, 0);
946 TREE_CHAIN (new_field) = TYPE_FIELDS (new_record_type);
947 TYPE_FIELDS (new_record_type) = new_field;
949 /* If old_field is a QUAL_UNION_TYPE, take its size as being
950 zero. The only time it's not the last field of the record
951 is when there are other components at fixed positions after
952 it (meaning there was a rep clause for every field) and we
953 want to be able to encode them. */
954 last_pos = size_binop (PLUS_EXPR, bit_position (old_field),
955 (TREE_CODE (TREE_TYPE (old_field))
958 : DECL_SIZE (old_field));
959 prev_old_field = old_field;
962 TYPE_FIELDS (new_record_type)
963 = nreverse (TYPE_FIELDS (new_record_type));
965 rest_of_type_decl_compilation (TYPE_STUB_DECL (new_record_type));
968 rest_of_type_decl_compilation (TYPE_STUB_DECL (record_type));
971 /* Append PARALLEL_TYPE on the chain of parallel types for decl. */
974 add_parallel_type (tree decl, tree parallel_type)
978 while (DECL_PARALLEL_TYPE (d))
979 d = TYPE_STUB_DECL (DECL_PARALLEL_TYPE (d));
981 SET_DECL_PARALLEL_TYPE (d, parallel_type);
984 /* Return the parallel type associated to a type, if any. */
987 get_parallel_type (tree type)
989 if (TYPE_STUB_DECL (type))
990 return DECL_PARALLEL_TYPE (TYPE_STUB_DECL (type));
995 /* Utility function of above to merge LAST_SIZE, the previous size of a record
996 with FIRST_BIT and SIZE that describe a field. SPECIAL is true if this
997 represents a QUAL_UNION_TYPE in which case we must look for COND_EXPRs and
998 replace a value of zero with the old size. If HAS_REP is true, we take the
999 MAX of the end position of this field with LAST_SIZE. In all other cases,
1000 we use FIRST_BIT plus SIZE. Return an expression for the size. */
1003 merge_sizes (tree last_size, tree first_bit, tree size, bool special,
1006 tree type = TREE_TYPE (last_size);
1009 if (!special || TREE_CODE (size) != COND_EXPR)
1011 new = size_binop (PLUS_EXPR, first_bit, size);
1013 new = size_binop (MAX_EXPR, last_size, new);
1017 new = fold_build3 (COND_EXPR, type, TREE_OPERAND (size, 0),
1018 integer_zerop (TREE_OPERAND (size, 1))
1019 ? last_size : merge_sizes (last_size, first_bit,
1020 TREE_OPERAND (size, 1),
1022 integer_zerop (TREE_OPERAND (size, 2))
1023 ? last_size : merge_sizes (last_size, first_bit,
1024 TREE_OPERAND (size, 2),
1027 /* We don't need any NON_VALUE_EXPRs and they can confuse us (especially
1028 when fed through substitute_in_expr) into thinking that a constant
1029 size is not constant. */
1030 while (TREE_CODE (new) == NON_LVALUE_EXPR)
1031 new = TREE_OPERAND (new, 0);
1036 /* Utility function of above to see if OP0 and OP1, both of SIZETYPE, are
1037 related by the addition of a constant. Return that constant if so. */
1040 compute_related_constant (tree op0, tree op1)
1042 tree op0_var, op1_var;
1043 tree op0_con = split_plus (op0, &op0_var);
1044 tree op1_con = split_plus (op1, &op1_var);
1045 tree result = size_binop (MINUS_EXPR, op0_con, op1_con);
1047 if (operand_equal_p (op0_var, op1_var, 0))
1049 else if (operand_equal_p (op0, size_binop (PLUS_EXPR, op1_var, result), 0))
1055 /* Utility function of above to split a tree OP which may be a sum, into a
1056 constant part, which is returned, and a variable part, which is stored
1057 in *PVAR. *PVAR may be bitsize_zero_node. All operations must be of
1061 split_plus (tree in, tree *pvar)
1063 /* Strip NOPS in order to ease the tree traversal and maximize the
1064 potential for constant or plus/minus discovery. We need to be careful
1065 to always return and set *pvar to bitsizetype trees, but it's worth
1069 *pvar = convert (bitsizetype, in);
1071 if (TREE_CODE (in) == INTEGER_CST)
1073 *pvar = bitsize_zero_node;
1074 return convert (bitsizetype, in);
1076 else if (TREE_CODE (in) == PLUS_EXPR || TREE_CODE (in) == MINUS_EXPR)
1078 tree lhs_var, rhs_var;
1079 tree lhs_con = split_plus (TREE_OPERAND (in, 0), &lhs_var);
1080 tree rhs_con = split_plus (TREE_OPERAND (in, 1), &rhs_var);
1082 if (lhs_var == TREE_OPERAND (in, 0)
1083 && rhs_var == TREE_OPERAND (in, 1))
1084 return bitsize_zero_node;
1086 *pvar = size_binop (TREE_CODE (in), lhs_var, rhs_var);
1087 return size_binop (TREE_CODE (in), lhs_con, rhs_con);
1090 return bitsize_zero_node;
1093 /* Return a FUNCTION_TYPE node. RETURN_TYPE is the type returned by the
1094 subprogram. If it is void_type_node, then we are dealing with a procedure,
1095 otherwise we are dealing with a function. PARAM_DECL_LIST is a list of
1096 PARM_DECL nodes that are the subprogram arguments. CICO_LIST is the
1097 copy-in/copy-out list to be stored into TYPE_CICO_LIST.
1098 RETURNS_UNCONSTRAINED is true if the function returns an unconstrained
1099 object. RETURNS_BY_REF is true if the function returns by reference.
1100 RETURNS_BY_TARGET_PTR is true if the function is to be passed (as its
1101 first parameter) the address of the place to copy its result. */
1104 create_subprog_type (tree return_type, tree param_decl_list, tree cico_list,
1105 bool returns_unconstrained, bool returns_by_ref,
1106 bool returns_by_target_ptr)
1108 /* A chain of TREE_LIST nodes whose TREE_VALUEs are the data type nodes of
1109 the subprogram formal parameters. This list is generated by traversing the
1110 input list of PARM_DECL nodes. */
1111 tree param_type_list = NULL;
1115 for (param_decl = param_decl_list; param_decl;
1116 param_decl = TREE_CHAIN (param_decl))
1117 param_type_list = tree_cons (NULL_TREE, TREE_TYPE (param_decl),
1120 /* The list of the function parameter types has to be terminated by the void
1121 type to signal to the back-end that we are not dealing with a variable
1122 parameter subprogram, but that the subprogram has a fixed number of
1124 param_type_list = tree_cons (NULL_TREE, void_type_node, param_type_list);
1126 /* The list of argument types has been created in reverse
1128 param_type_list = nreverse (param_type_list);
1130 type = build_function_type (return_type, param_type_list);
1132 /* TYPE may have been shared since GCC hashes types. If it has a CICO_LIST
1133 or the new type should, make a copy of TYPE. Likewise for
1134 RETURNS_UNCONSTRAINED and RETURNS_BY_REF. */
1135 if (TYPE_CI_CO_LIST (type) || cico_list
1136 || TYPE_RETURNS_UNCONSTRAINED_P (type) != returns_unconstrained
1137 || TYPE_RETURNS_BY_REF_P (type) != returns_by_ref
1138 || TYPE_RETURNS_BY_TARGET_PTR_P (type) != returns_by_target_ptr)
1139 type = copy_type (type);
1141 TYPE_CI_CO_LIST (type) = cico_list;
1142 TYPE_RETURNS_UNCONSTRAINED_P (type) = returns_unconstrained;
1143 TYPE_RETURNS_BY_REF_P (type) = returns_by_ref;
1144 TYPE_RETURNS_BY_TARGET_PTR_P (type) = returns_by_target_ptr;
1148 /* Return a copy of TYPE but safe to modify in any way. */
1151 copy_type (tree type)
1153 tree new = copy_node (type);
1155 /* copy_node clears this field instead of copying it, because it is
1156 aliased with TREE_CHAIN. */
1157 TYPE_STUB_DECL (new) = TYPE_STUB_DECL (type);
1159 TYPE_POINTER_TO (new) = 0;
1160 TYPE_REFERENCE_TO (new) = 0;
1161 TYPE_MAIN_VARIANT (new) = new;
1162 TYPE_NEXT_VARIANT (new) = 0;
1167 /* Return an INTEGER_TYPE of SIZETYPE with range MIN to MAX and whose
1168 TYPE_INDEX_TYPE is INDEX. GNAT_NODE is used for the position of
1172 create_index_type (tree min, tree max, tree index, Node_Id gnat_node)
1174 /* First build a type for the desired range. */
1175 tree type = build_index_2_type (min, max);
1177 /* If this type has the TYPE_INDEX_TYPE we want, return it. Otherwise, if it
1178 doesn't have TYPE_INDEX_TYPE set, set it to INDEX. If TYPE_INDEX_TYPE
1179 is set, but not to INDEX, make a copy of this type with the requested
1180 index type. Note that we have no way of sharing these types, but that's
1181 only a small hole. */
1182 if (TYPE_INDEX_TYPE (type) == index)
1184 else if (TYPE_INDEX_TYPE (type))
1185 type = copy_type (type);
1187 SET_TYPE_INDEX_TYPE (type, index);
1188 create_type_decl (NULL_TREE, type, NULL, true, false, gnat_node);
1192 /* Return a TYPE_DECL node suitable for the TYPE_STUB_DECL field of a type.
1193 TYPE_NAME gives the name of the type and TYPE is a ..._TYPE node giving
1197 create_type_stub_decl (tree type_name, tree type)
1199 /* Using a named TYPE_DECL ensures that a type name marker is emitted in
1200 STABS while setting DECL_ARTIFICIAL ensures that no DW_TAG_typedef is
1201 emitted in DWARF. */
1202 tree type_decl = build_decl (TYPE_DECL, type_name, type);
1203 DECL_ARTIFICIAL (type_decl) = 1;
1207 /* Return a TYPE_DECL node. TYPE_NAME gives the name of the type and TYPE
1208 is a ..._TYPE node giving its data type. ARTIFICIAL_P is true if this
1209 is a declaration that was generated by the compiler. DEBUG_INFO_P is
1210 true if we need to write debug information about this type. GNAT_NODE
1211 is used for the position of the decl. */
1214 create_type_decl (tree type_name, tree type, struct attrib *attr_list,
1215 bool artificial_p, bool debug_info_p, Node_Id gnat_node)
1217 enum tree_code code = TREE_CODE (type);
1218 bool named = TYPE_NAME (type) && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL;
1221 /* Only the builtin TYPE_STUB_DECL should be used for dummy types. */
1222 gcc_assert (!TYPE_IS_DUMMY_P (type));
1224 /* If the type hasn't been named yet, we're naming it; preserve an existing
1225 TYPE_STUB_DECL that has been attached to it for some purpose. */
1226 if (!named && TYPE_STUB_DECL (type))
1228 type_decl = TYPE_STUB_DECL (type);
1229 DECL_NAME (type_decl) = type_name;
1232 type_decl = build_decl (TYPE_DECL, type_name, type);
1234 DECL_ARTIFICIAL (type_decl) = artificial_p;
1235 gnat_pushdecl (type_decl, gnat_node);
1236 process_attributes (type_decl, attr_list);
1238 /* If we're naming the type, equate the TYPE_STUB_DECL to the name.
1239 This causes the name to be also viewed as a "tag" by the debug
1240 back-end, with the advantage that no DW_TAG_typedef is emitted
1241 for artificial "tagged" types in DWARF. */
1243 TYPE_STUB_DECL (type) = type_decl;
1245 /* Pass the type declaration to the debug back-end unless this is an
1246 UNCONSTRAINED_ARRAY_TYPE that the back-end does not support, or a
1247 type for which debugging information was not requested, or else an
1248 ENUMERAL_TYPE or RECORD_TYPE (except for fat pointers) which are
1249 handled separately. And do not pass dummy types either. */
1250 if (code == UNCONSTRAINED_ARRAY_TYPE || !debug_info_p)
1251 DECL_IGNORED_P (type_decl) = 1;
1252 else if (code != ENUMERAL_TYPE
1253 && (code != RECORD_TYPE || TYPE_IS_FAT_POINTER_P (type))
1254 && !((code == POINTER_TYPE || code == REFERENCE_TYPE)
1255 && TYPE_IS_DUMMY_P (TREE_TYPE (type)))
1256 && !(code == RECORD_TYPE
1258 (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (type))))))
1259 rest_of_type_decl_compilation (type_decl);
1264 /* Return a VAR_DECL or CONST_DECL node.
1266 VAR_NAME gives the name of the variable. ASM_NAME is its assembler name
1267 (if provided). TYPE is its data type (a GCC ..._TYPE node). VAR_INIT is
1268 the GCC tree for an optional initial expression; NULL_TREE if none.
1270 CONST_FLAG is true if this variable is constant, in which case we might
1271 return a CONST_DECL node unless CONST_DECL_ALLOWED_P is false.
1273 PUBLIC_FLAG is true if this is for a reference to a public entity or for a
1274 definition to be made visible outside of the current compilation unit, for
1275 instance variable definitions in a package specification.
1277 EXTERN_FLAG is true when processing an external variable declaration (as
1278 opposed to a definition: no storage is to be allocated for the variable).
1280 STATIC_FLAG is only relevant when not at top level. In that case
1281 it indicates whether to always allocate storage to the variable.
1283 GNAT_NODE is used for the position of the decl. */
1286 create_var_decl_1 (tree var_name, tree asm_name, tree type, tree var_init,
1287 bool const_flag, bool public_flag, bool extern_flag,
1288 bool static_flag, bool const_decl_allowed_p,
1289 struct attrib *attr_list, Node_Id gnat_node)
1293 && gnat_types_compatible_p (type, TREE_TYPE (var_init))
1294 && (global_bindings_p () || static_flag
1295 ? initializer_constant_valid_p (var_init, TREE_TYPE (var_init)) != 0
1296 : TREE_CONSTANT (var_init)));
1298 /* Whether we will make TREE_CONSTANT the DECL we produce here, in which
1299 case the initializer may be used in-lieu of the DECL node (as done in
1300 Identifier_to_gnu). This is useful to prevent the need of elaboration
1301 code when an identifier for which such a decl is made is in turn used as
1302 an initializer. We used to rely on CONST vs VAR_DECL for this purpose,
1303 but extra constraints apply to this choice (see below) and are not
1304 relevant to the distinction we wish to make. */
1305 bool constant_p = const_flag && init_const;
1307 /* The actual DECL node. CONST_DECL was initially intended for enumerals
1308 and may be used for scalars in general but not for aggregates. */
1310 = build_decl ((constant_p && const_decl_allowed_p
1311 && !AGGREGATE_TYPE_P (type)) ? CONST_DECL : VAR_DECL,
1314 /* If this is external, throw away any initializations (they will be done
1315 elsewhere) unless this is a constant for which we would like to remain
1316 able to get the initializer. If we are defining a global here, leave a
1317 constant initialization and save any variable elaborations for the
1318 elaboration routine. If we are just annotating types, throw away the
1319 initialization if it isn't a constant. */
1320 if ((extern_flag && !constant_p)
1321 || (type_annotate_only && var_init && !TREE_CONSTANT (var_init)))
1322 var_init = NULL_TREE;
1324 /* At the global level, an initializer requiring code to be generated
1325 produces elaboration statements. Check that such statements are allowed,
1326 that is, not violating a No_Elaboration_Code restriction. */
1327 if (global_bindings_p () && var_init != 0 && ! init_const)
1328 Check_Elaboration_Code_Allowed (gnat_node);
1330 /* Ada doesn't feature Fortran-like COMMON variables so we shouldn't
1331 try to fiddle with DECL_COMMON. However, on platforms that don't
1332 support global BSS sections, uninitialized global variables would
1333 go in DATA instead, thus increasing the size of the executable. */
1335 && TREE_CODE (var_decl) == VAR_DECL
1336 && !have_global_bss_p ())
1337 DECL_COMMON (var_decl) = 1;
1338 DECL_INITIAL (var_decl) = var_init;
1339 TREE_READONLY (var_decl) = const_flag;
1340 DECL_EXTERNAL (var_decl) = extern_flag;
1341 TREE_PUBLIC (var_decl) = public_flag || extern_flag;
1342 TREE_CONSTANT (var_decl) = constant_p;
1343 TREE_THIS_VOLATILE (var_decl) = TREE_SIDE_EFFECTS (var_decl)
1344 = TYPE_VOLATILE (type);
1346 /* If it's public and not external, always allocate storage for it.
1347 At the global binding level we need to allocate static storage for the
1348 variable if and only if it's not external. If we are not at the top level
1349 we allocate automatic storage unless requested not to. */
1350 TREE_STATIC (var_decl)
1351 = !extern_flag && (public_flag || static_flag || global_bindings_p ());
1353 if (asm_name && VAR_OR_FUNCTION_DECL_P (var_decl))
1354 SET_DECL_ASSEMBLER_NAME (var_decl, asm_name);
1356 process_attributes (var_decl, attr_list);
1358 /* Add this decl to the current binding level. */
1359 gnat_pushdecl (var_decl, gnat_node);
1361 if (TREE_SIDE_EFFECTS (var_decl))
1362 TREE_ADDRESSABLE (var_decl) = 1;
1364 if (TREE_CODE (var_decl) != CONST_DECL)
1366 if (global_bindings_p ())
1367 rest_of_decl_compilation (var_decl, true, 0);
1370 expand_decl (var_decl);
1375 /* Return true if TYPE, an aggregate type, contains (or is) an array. */
1378 aggregate_type_contains_array_p (tree type)
1380 switch (TREE_CODE (type))
1384 case QUAL_UNION_TYPE:
1387 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1388 if (AGGREGATE_TYPE_P (TREE_TYPE (field))
1389 && aggregate_type_contains_array_p (TREE_TYPE (field)))
1402 /* Returns a FIELD_DECL node. FIELD_NAME the field name, FIELD_TYPE is its
1403 type, and RECORD_TYPE is the type of the parent. PACKED is nonzero if
1404 this field is in a record type with a "pragma pack". If SIZE is nonzero
1405 it is the specified size for this field. If POS is nonzero, it is the bit
1406 position. If ADDRESSABLE is nonzero, it means we are allowed to take
1407 the address of this field for aliasing purposes. If it is negative, we
1408 should not make a bitfield, which is used by make_aligning_type. */
1411 create_field_decl (tree field_name, tree field_type, tree record_type,
1412 int packed, tree size, tree pos, int addressable)
1414 tree field_decl = build_decl (FIELD_DECL, field_name, field_type);
1416 DECL_CONTEXT (field_decl) = record_type;
1417 TREE_READONLY (field_decl) = TYPE_READONLY (field_type);
1419 /* If FIELD_TYPE is BLKmode, we must ensure this is aligned to at least a
1420 byte boundary since GCC cannot handle less-aligned BLKmode bitfields.
1421 Likewise for an aggregate without specified position that contains an
1422 array, because in this case slices of variable length of this array
1423 must be handled by GCC and variable-sized objects need to be aligned
1424 to at least a byte boundary. */
1425 if (packed && (TYPE_MODE (field_type) == BLKmode
1427 && AGGREGATE_TYPE_P (field_type)
1428 && aggregate_type_contains_array_p (field_type))))
1429 DECL_ALIGN (field_decl) = BITS_PER_UNIT;
1431 /* If a size is specified, use it. Otherwise, if the record type is packed
1432 compute a size to use, which may differ from the object's natural size.
1433 We always set a size in this case to trigger the checks for bitfield
1434 creation below, which is typically required when no position has been
1437 size = convert (bitsizetype, size);
1438 else if (packed == 1)
1440 size = rm_size (field_type);
1442 /* For a constant size larger than MAX_FIXED_MODE_SIZE, round up to
1444 if (TREE_CODE (size) == INTEGER_CST
1445 && compare_tree_int (size, MAX_FIXED_MODE_SIZE) > 0)
1446 size = round_up (size, BITS_PER_UNIT);
1449 /* If we may, according to ADDRESSABLE, make a bitfield if a size is
1450 specified for two reasons: first if the size differs from the natural
1451 size. Second, if the alignment is insufficient. There are a number of
1452 ways the latter can be true.
1454 We never make a bitfield if the type of the field has a nonconstant size,
1455 because no such entity requiring bitfield operations should reach here.
1457 We do *preventively* make a bitfield when there might be the need for it
1458 but we don't have all the necessary information to decide, as is the case
1459 of a field with no specified position in a packed record.
1461 We also don't look at STRICT_ALIGNMENT here, and rely on later processing
1462 in layout_decl or finish_record_type to clear the bit_field indication if
1463 it is in fact not needed. */
1464 if (addressable >= 0
1466 && TREE_CODE (size) == INTEGER_CST
1467 && TREE_CODE (TYPE_SIZE (field_type)) == INTEGER_CST
1468 && (!tree_int_cst_equal (size, TYPE_SIZE (field_type))
1469 || (pos && !value_factor_p (pos, TYPE_ALIGN (field_type)))
1471 || (TYPE_ALIGN (record_type) != 0
1472 && TYPE_ALIGN (record_type) < TYPE_ALIGN (field_type))))
1474 DECL_BIT_FIELD (field_decl) = 1;
1475 DECL_SIZE (field_decl) = size;
1476 if (!packed && !pos)
1477 DECL_ALIGN (field_decl)
1478 = (TYPE_ALIGN (record_type) != 0
1479 ? MIN (TYPE_ALIGN (record_type), TYPE_ALIGN (field_type))
1480 : TYPE_ALIGN (field_type));
1483 DECL_PACKED (field_decl) = pos ? DECL_BIT_FIELD (field_decl) : packed;
1485 /* Bump the alignment if need be, either for bitfield/packing purposes or
1486 to satisfy the type requirements if no such consideration applies. When
1487 we get the alignment from the type, indicate if this is from an explicit
1488 user request, which prevents stor-layout from lowering it later on. */
1490 unsigned int bit_align
1491 = (DECL_BIT_FIELD (field_decl) ? 1
1492 : packed && TYPE_MODE (field_type) != BLKmode ? BITS_PER_UNIT : 0);
1494 if (bit_align > DECL_ALIGN (field_decl))
1495 DECL_ALIGN (field_decl) = bit_align;
1496 else if (!bit_align && TYPE_ALIGN (field_type) > DECL_ALIGN (field_decl))
1498 DECL_ALIGN (field_decl) = TYPE_ALIGN (field_type);
1499 DECL_USER_ALIGN (field_decl) = TYPE_USER_ALIGN (field_type);
1505 /* We need to pass in the alignment the DECL is known to have.
1506 This is the lowest-order bit set in POS, but no more than
1507 the alignment of the record, if one is specified. Note
1508 that an alignment of 0 is taken as infinite. */
1509 unsigned int known_align;
1511 if (host_integerp (pos, 1))
1512 known_align = tree_low_cst (pos, 1) & - tree_low_cst (pos, 1);
1514 known_align = BITS_PER_UNIT;
1516 if (TYPE_ALIGN (record_type)
1517 && (known_align == 0 || known_align > TYPE_ALIGN (record_type)))
1518 known_align = TYPE_ALIGN (record_type);
1520 layout_decl (field_decl, known_align);
1521 SET_DECL_OFFSET_ALIGN (field_decl,
1522 host_integerp (pos, 1) ? BIGGEST_ALIGNMENT
1524 pos_from_bit (&DECL_FIELD_OFFSET (field_decl),
1525 &DECL_FIELD_BIT_OFFSET (field_decl),
1526 DECL_OFFSET_ALIGN (field_decl), pos);
1529 /* In addition to what our caller says, claim the field is addressable if we
1530 know that its type is not suitable.
1532 The field may also be "technically" nonaddressable, meaning that even if
1533 we attempt to take the field's address we will actually get the address
1534 of a copy. This is the case for true bitfields, but the DECL_BIT_FIELD
1535 value we have at this point is not accurate enough, so we don't account
1536 for this here and let finish_record_type decide. */
1537 if (!addressable && !type_for_nonaliased_component_p (field_type))
1540 DECL_NONADDRESSABLE_P (field_decl) = !addressable;
1545 /* Returns a PARM_DECL node. PARAM_NAME is the name of the parameter,
1546 PARAM_TYPE is its type. READONLY is true if the parameter is
1547 readonly (either an In parameter or an address of a pass-by-ref
1551 create_param_decl (tree param_name, tree param_type, bool readonly)
1553 tree param_decl = build_decl (PARM_DECL, param_name, param_type);
1555 /* Honor targetm.calls.promote_prototypes(), as not doing so can
1556 lead to various ABI violations. */
1557 if (targetm.calls.promote_prototypes (param_type)
1558 && (TREE_CODE (param_type) == INTEGER_TYPE
1559 || TREE_CODE (param_type) == ENUMERAL_TYPE
1560 || TREE_CODE (param_type) == BOOLEAN_TYPE)
1561 && TYPE_PRECISION (param_type) < TYPE_PRECISION (integer_type_node))
1563 /* We have to be careful about biased types here. Make a subtype
1564 of integer_type_node with the proper biasing. */
1565 if (TREE_CODE (param_type) == INTEGER_TYPE
1566 && TYPE_BIASED_REPRESENTATION_P (param_type))
1569 = copy_type (build_range_type (integer_type_node,
1570 TYPE_MIN_VALUE (param_type),
1571 TYPE_MAX_VALUE (param_type)));
1573 TYPE_BIASED_REPRESENTATION_P (param_type) = 1;
1576 param_type = integer_type_node;
1579 DECL_ARG_TYPE (param_decl) = param_type;
1580 TREE_READONLY (param_decl) = readonly;
1584 /* Given a DECL and ATTR_LIST, process the listed attributes. */
1587 process_attributes (tree decl, struct attrib *attr_list)
1589 for (; attr_list; attr_list = attr_list->next)
1590 switch (attr_list->type)
1592 case ATTR_MACHINE_ATTRIBUTE:
1593 decl_attributes (&decl, tree_cons (attr_list->name, attr_list->args,
1595 ATTR_FLAG_TYPE_IN_PLACE);
1598 case ATTR_LINK_ALIAS:
1599 if (! DECL_EXTERNAL (decl))
1601 TREE_STATIC (decl) = 1;
1602 assemble_alias (decl, attr_list->name);
1606 case ATTR_WEAK_EXTERNAL:
1608 declare_weak (decl);
1610 post_error ("?weak declarations not supported on this target",
1611 attr_list->error_point);
1614 case ATTR_LINK_SECTION:
1615 if (targetm.have_named_sections)
1617 DECL_SECTION_NAME (decl)
1618 = build_string (IDENTIFIER_LENGTH (attr_list->name),
1619 IDENTIFIER_POINTER (attr_list->name));
1620 DECL_COMMON (decl) = 0;
1623 post_error ("?section attributes are not supported for this target",
1624 attr_list->error_point);
1627 case ATTR_LINK_CONSTRUCTOR:
1628 DECL_STATIC_CONSTRUCTOR (decl) = 1;
1629 TREE_USED (decl) = 1;
1632 case ATTR_LINK_DESTRUCTOR:
1633 DECL_STATIC_DESTRUCTOR (decl) = 1;
1634 TREE_USED (decl) = 1;
1637 case ATTR_THREAD_LOCAL_STORAGE:
1638 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
1639 DECL_COMMON (decl) = 0;
1644 /* Record a global renaming pointer. */
1647 record_global_renaming_pointer (tree decl)
1649 gcc_assert (DECL_RENAMED_OBJECT (decl));
1650 VEC_safe_push (tree, gc, global_renaming_pointers, decl);
1653 /* Invalidate the global renaming pointers. */
1656 invalidate_global_renaming_pointers (void)
1661 for (i = 0; VEC_iterate(tree, global_renaming_pointers, i, iter); i++)
1662 SET_DECL_RENAMED_OBJECT (iter, NULL_TREE);
1664 VEC_free (tree, gc, global_renaming_pointers);
1667 /* Return true if VALUE is a known to be a multiple of FACTOR, which must be
1671 value_factor_p (tree value, HOST_WIDE_INT factor)
1673 if (host_integerp (value, 1))
1674 return tree_low_cst (value, 1) % factor == 0;
1676 if (TREE_CODE (value) == MULT_EXPR)
1677 return (value_factor_p (TREE_OPERAND (value, 0), factor)
1678 || value_factor_p (TREE_OPERAND (value, 1), factor));
1683 /* Given 2 consecutive field decls PREV_FIELD and CURR_FIELD, return true
1684 unless we can prove these 2 fields are laid out in such a way that no gap
1685 exist between the end of PREV_FIELD and the beginning of CURR_FIELD. OFFSET
1686 is the distance in bits between the end of PREV_FIELD and the starting
1687 position of CURR_FIELD. It is ignored if null. */
1690 potential_alignment_gap (tree prev_field, tree curr_field, tree offset)
1692 /* If this is the first field of the record, there cannot be any gap */
1696 /* If the previous field is a union type, then return False: The only
1697 time when such a field is not the last field of the record is when
1698 there are other components at fixed positions after it (meaning there
1699 was a rep clause for every field), in which case we don't want the
1700 alignment constraint to override them. */
1701 if (TREE_CODE (TREE_TYPE (prev_field)) == QUAL_UNION_TYPE)
1704 /* If the distance between the end of prev_field and the beginning of
1705 curr_field is constant, then there is a gap if the value of this
1706 constant is not null. */
1707 if (offset && host_integerp (offset, 1))
1708 return !integer_zerop (offset);
1710 /* If the size and position of the previous field are constant,
1711 then check the sum of this size and position. There will be a gap
1712 iff it is not multiple of the current field alignment. */
1713 if (host_integerp (DECL_SIZE (prev_field), 1)
1714 && host_integerp (bit_position (prev_field), 1))
1715 return ((tree_low_cst (bit_position (prev_field), 1)
1716 + tree_low_cst (DECL_SIZE (prev_field), 1))
1717 % DECL_ALIGN (curr_field) != 0);
1719 /* If both the position and size of the previous field are multiples
1720 of the current field alignment, there cannot be any gap. */
1721 if (value_factor_p (bit_position (prev_field), DECL_ALIGN (curr_field))
1722 && value_factor_p (DECL_SIZE (prev_field), DECL_ALIGN (curr_field)))
1725 /* Fallback, return that there may be a potential gap */
1729 /* Returns a LABEL_DECL node for LABEL_NAME. */
1732 create_label_decl (tree label_name)
1734 tree label_decl = build_decl (LABEL_DECL, label_name, void_type_node);
1736 DECL_CONTEXT (label_decl) = current_function_decl;
1737 DECL_MODE (label_decl) = VOIDmode;
1738 DECL_SOURCE_LOCATION (label_decl) = input_location;
1743 /* Returns a FUNCTION_DECL node. SUBPROG_NAME is the name of the subprogram,
1744 ASM_NAME is its assembler name, SUBPROG_TYPE is its type (a FUNCTION_TYPE
1745 node), PARAM_DECL_LIST is the list of the subprogram arguments (a list of
1746 PARM_DECL nodes chained through the TREE_CHAIN field).
1748 INLINE_FLAG, PUBLIC_FLAG, EXTERN_FLAG, and ATTR_LIST are used to set the
1749 appropriate fields in the FUNCTION_DECL. GNAT_NODE gives the location. */
1752 create_subprog_decl (tree subprog_name, tree asm_name,
1753 tree subprog_type, tree param_decl_list, bool inline_flag,
1754 bool public_flag, bool extern_flag,
1755 struct attrib *attr_list, Node_Id gnat_node)
1757 tree return_type = TREE_TYPE (subprog_type);
1758 tree subprog_decl = build_decl (FUNCTION_DECL, subprog_name, subprog_type);
1760 /* If this is a non-inline function nested inside an inlined external
1761 function, we cannot honor both requests without cloning the nested
1762 function in the current unit since it is private to the other unit.
1763 We could inline the nested function as well but it's probably better
1764 to err on the side of too little inlining. */
1766 && current_function_decl
1767 && DECL_DECLARED_INLINE_P (current_function_decl)
1768 && DECL_EXTERNAL (current_function_decl))
1769 DECL_DECLARED_INLINE_P (current_function_decl) = 0;
1771 DECL_EXTERNAL (subprog_decl) = extern_flag;
1772 TREE_PUBLIC (subprog_decl) = public_flag;
1773 TREE_STATIC (subprog_decl) = 1;
1774 TREE_READONLY (subprog_decl) = TYPE_READONLY (subprog_type);
1775 TREE_THIS_VOLATILE (subprog_decl) = TYPE_VOLATILE (subprog_type);
1776 TREE_SIDE_EFFECTS (subprog_decl) = TYPE_VOLATILE (subprog_type);
1777 DECL_DECLARED_INLINE_P (subprog_decl) = inline_flag;
1778 DECL_ARGUMENTS (subprog_decl) = param_decl_list;
1779 DECL_RESULT (subprog_decl) = build_decl (RESULT_DECL, 0, return_type);
1780 DECL_ARTIFICIAL (DECL_RESULT (subprog_decl)) = 1;
1781 DECL_IGNORED_P (DECL_RESULT (subprog_decl)) = 1;
1783 /* TREE_ADDRESSABLE is set on the result type to request the use of the
1784 target by-reference return mechanism. This is not supported all the
1785 way down to RTL expansion with GCC 4, which ICEs on temporary creation
1786 attempts with such a type and expects DECL_BY_REFERENCE to be set on
1787 the RESULT_DECL instead - see gnat_genericize for more details. */
1788 if (TREE_ADDRESSABLE (TREE_TYPE (DECL_RESULT (subprog_decl))))
1790 tree result_decl = DECL_RESULT (subprog_decl);
1792 TREE_ADDRESSABLE (TREE_TYPE (result_decl)) = 0;
1793 DECL_BY_REFERENCE (result_decl) = 1;
1798 SET_DECL_ASSEMBLER_NAME (subprog_decl, asm_name);
1800 /* The expand_main_function circuitry expects "main_identifier_node" to
1801 designate the DECL_NAME of the 'main' entry point, in turn expected
1802 to be declared as the "main" function literally by default. Ada
1803 program entry points are typically declared with a different name
1804 within the binder generated file, exported as 'main' to satisfy the
1805 system expectations. Redirect main_identifier_node in this case. */
1806 if (asm_name == main_identifier_node)
1807 main_identifier_node = DECL_NAME (subprog_decl);
1810 process_attributes (subprog_decl, attr_list);
1812 /* Add this decl to the current binding level. */
1813 gnat_pushdecl (subprog_decl, gnat_node);
1815 /* Output the assembler code and/or RTL for the declaration. */
1816 rest_of_decl_compilation (subprog_decl, global_bindings_p (), 0);
1818 return subprog_decl;
1821 /* Set up the framework for generating code for SUBPROG_DECL, a subprogram
1822 body. This routine needs to be invoked before processing the declarations
1823 appearing in the subprogram. */
1826 begin_subprog_body (tree subprog_decl)
1830 current_function_decl = subprog_decl;
1831 announce_function (subprog_decl);
1833 /* Enter a new binding level and show that all the parameters belong to
1836 for (param_decl = DECL_ARGUMENTS (subprog_decl); param_decl;
1837 param_decl = TREE_CHAIN (param_decl))
1838 DECL_CONTEXT (param_decl) = subprog_decl;
1840 make_decl_rtl (subprog_decl);
1842 /* We handle pending sizes via the elaboration of types, so we don't need to
1843 save them. This causes them to be marked as part of the outer function
1844 and then discarded. */
1845 get_pending_sizes ();
1849 /* Helper for the genericization callback. Return a dereference of VAL
1850 if it is of a reference type. */
1853 convert_from_reference (tree val)
1855 tree value_type, ref;
1857 if (TREE_CODE (TREE_TYPE (val)) != REFERENCE_TYPE)
1860 value_type = TREE_TYPE (TREE_TYPE (val));
1861 ref = build1 (INDIRECT_REF, value_type, val);
1863 /* See if what we reference is CONST or VOLATILE, which requires
1864 looking into array types to get to the component type. */
1866 while (TREE_CODE (value_type) == ARRAY_TYPE)
1867 value_type = TREE_TYPE (value_type);
1870 = (TYPE_QUALS (value_type) & TYPE_QUAL_CONST);
1871 TREE_THIS_VOLATILE (ref)
1872 = (TYPE_QUALS (value_type) & TYPE_QUAL_VOLATILE);
1874 TREE_SIDE_EFFECTS (ref)
1875 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (val));
1880 /* Helper for the genericization callback. Returns true if T denotes
1881 a RESULT_DECL with DECL_BY_REFERENCE set. */
1884 is_byref_result (tree t)
1886 return (TREE_CODE (t) == RESULT_DECL && DECL_BY_REFERENCE (t));
1890 /* Tree walking callback for gnat_genericize. Currently ...
1892 o Adjust references to the function's DECL_RESULT if it is marked
1893 DECL_BY_REFERENCE and so has had its type turned into a reference
1894 type at the end of the function compilation. */
1897 gnat_genericize_r (tree *stmt_p, int *walk_subtrees, void *data)
1899 /* This implementation is modeled after what the C++ front-end is
1900 doing, basis of the downstream passes behavior. */
1902 tree stmt = *stmt_p;
1903 struct pointer_set_t *p_set = (struct pointer_set_t*) data;
1905 /* If we have a direct mention of the result decl, dereference. */
1906 if (is_byref_result (stmt))
1908 *stmt_p = convert_from_reference (stmt);
1913 /* Otherwise, no need to walk the same tree twice. */
1914 if (pointer_set_contains (p_set, stmt))
1920 /* If we are taking the address of what now is a reference, just get the
1922 if (TREE_CODE (stmt) == ADDR_EXPR
1923 && is_byref_result (TREE_OPERAND (stmt, 0)))
1925 *stmt_p = convert (TREE_TYPE (stmt), TREE_OPERAND (stmt, 0));
1929 /* Don't dereference an by-reference RESULT_DECL inside a RETURN_EXPR. */
1930 else if (TREE_CODE (stmt) == RETURN_EXPR
1931 && TREE_OPERAND (stmt, 0)
1932 && is_byref_result (TREE_OPERAND (stmt, 0)))
1935 /* Don't look inside trees that cannot embed references of interest. */
1936 else if (IS_TYPE_OR_DECL_P (stmt))
1939 pointer_set_insert (p_set, *stmt_p);
1944 /* Perform lowering of Ada trees to GENERIC. In particular:
1946 o Turn a DECL_BY_REFERENCE RESULT_DECL into a real by-reference decl
1947 and adjust all the references to this decl accordingly. */
1950 gnat_genericize (tree fndecl)
1952 /* Prior to GCC 4, an explicit By_Reference result mechanism for a function
1953 was handled by simply setting TREE_ADDRESSABLE on the result type.
1954 Everything required to actually pass by invisible ref using the target
1955 mechanism (e.g. extra parameter) was handled at RTL expansion time.
1957 This doesn't work with GCC 4 any more for several reasons. First, the
1958 gimplification process might need the creation of temporaries of this
1959 type, and the gimplifier ICEs on such attempts. Second, the middle-end
1960 now relies on a different attribute for such cases (DECL_BY_REFERENCE on
1961 RESULT/PARM_DECLs), and expects the user invisible by-reference-ness to
1962 be explicitly accounted for by the front-end in the function body.
1964 We achieve the complete transformation in two steps:
1966 1/ create_subprog_decl performs early attribute tweaks: it clears
1967 TREE_ADDRESSABLE from the result type and sets DECL_BY_REFERENCE on
1968 the result decl. The former ensures that the bit isn't set in the GCC
1969 tree saved for the function, so prevents ICEs on temporary creation.
1970 The latter we use here to trigger the rest of the processing.
1972 2/ This function performs the type transformation on the result decl
1973 and adjusts all the references to this decl from the function body
1976 Clearing TREE_ADDRESSABLE from the type differs from the C++ front-end
1977 strategy, which escapes the gimplifier temporary creation issues by
1978 creating it's own temporaries using TARGET_EXPR nodes. Our way relies
1979 on simple specific support code in aggregate_value_p to look at the
1980 target function result decl explicitly. */
1982 struct pointer_set_t *p_set;
1983 tree decl_result = DECL_RESULT (fndecl);
1985 if (!DECL_BY_REFERENCE (decl_result))
1988 /* Make the DECL_RESULT explicitly by-reference and adjust all the
1989 occurrences in the function body using the common tree-walking facility.
1990 We want to see every occurrence of the result decl to adjust the
1991 referencing tree, so need to use our own pointer set to control which
1992 trees should be visited again or not. */
1994 p_set = pointer_set_create ();
1996 TREE_TYPE (decl_result) = build_reference_type (TREE_TYPE (decl_result));
1997 TREE_ADDRESSABLE (decl_result) = 0;
1998 relayout_decl (decl_result);
2000 walk_tree (&DECL_SAVED_TREE (fndecl), gnat_genericize_r, p_set, NULL);
2002 pointer_set_destroy (p_set);
2005 /* Finish the definition of the current subprogram BODY and compile it all the
2006 way to assembler language output. ELAB_P tells if this is called for an
2007 elaboration routine, to be entirely discarded if empty. */
2010 end_subprog_body (tree body, bool elab_p)
2012 tree fndecl = current_function_decl;
2014 /* Mark the BLOCK for this level as being for this function and pop the
2015 level. Since the vars in it are the parameters, clear them. */
2016 BLOCK_VARS (current_binding_level->block) = 0;
2017 BLOCK_SUPERCONTEXT (current_binding_level->block) = fndecl;
2018 DECL_INITIAL (fndecl) = current_binding_level->block;
2021 /* We handle pending sizes via the elaboration of types, so we don't
2022 need to save them. */
2023 get_pending_sizes ();
2025 /* Mark the RESULT_DECL as being in this subprogram. */
2026 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
2028 DECL_SAVED_TREE (fndecl) = body;
2030 current_function_decl = DECL_CONTEXT (fndecl);
2033 /* We cannot track the location of errors past this point. */
2034 error_gnat_node = Empty;
2036 /* If we're only annotating types, don't actually compile this function. */
2037 if (type_annotate_only)
2040 /* Perform the required pre-gimplification transformations on the tree. */
2041 gnat_genericize (fndecl);
2043 /* We do different things for nested and non-nested functions.
2044 ??? This should be in cgraph. */
2045 if (!DECL_CONTEXT (fndecl))
2047 gnat_gimplify_function (fndecl);
2049 /* If this is an empty elaboration proc, just discard the node.
2050 Otherwise, compile further. */
2051 if (elab_p && empty_body_p (gimple_body (fndecl)))
2052 cgraph_remove_node (cgraph_node (fndecl));
2054 cgraph_finalize_function (fndecl, false);
2057 /* Register this function with cgraph just far enough to get it
2058 added to our parent's nested function list. */
2059 (void) cgraph_node (fndecl);
2062 /* Convert FNDECL's code to GIMPLE and handle any nested functions. */
2065 gnat_gimplify_function (tree fndecl)
2067 struct cgraph_node *cgn;
2069 dump_function (TDI_original, fndecl);
2070 gimplify_function_tree (fndecl);
2071 dump_function (TDI_generic, fndecl);
2073 /* Convert all nested functions to GIMPLE now. We do things in this order
2074 so that items like VLA sizes are expanded properly in the context of the
2075 correct function. */
2076 cgn = cgraph_node (fndecl);
2077 for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
2078 gnat_gimplify_function (cgn->decl);
2082 gnat_builtin_function (tree decl)
2084 gnat_pushdecl (decl, Empty);
2088 /* Return an integer type with the number of bits of precision given by
2089 PRECISION. UNSIGNEDP is nonzero if the type is unsigned; otherwise
2090 it is a signed type. */
2093 gnat_type_for_size (unsigned precision, int unsignedp)
2098 if (precision <= 2 * MAX_BITS_PER_WORD
2099 && signed_and_unsigned_types[precision][unsignedp])
2100 return signed_and_unsigned_types[precision][unsignedp];
2103 t = make_unsigned_type (precision);
2105 t = make_signed_type (precision);
2107 if (precision <= 2 * MAX_BITS_PER_WORD)
2108 signed_and_unsigned_types[precision][unsignedp] = t;
2112 sprintf (type_name, "%sSIGNED_%d", unsignedp ? "UN" : "", precision);
2113 TYPE_NAME (t) = get_identifier (type_name);
2119 /* Likewise for floating-point types. */
2122 float_type_for_precision (int precision, enum machine_mode mode)
2127 if (float_types[(int) mode])
2128 return float_types[(int) mode];
2130 float_types[(int) mode] = t = make_node (REAL_TYPE);
2131 TYPE_PRECISION (t) = precision;
2134 gcc_assert (TYPE_MODE (t) == mode);
2137 sprintf (type_name, "FLOAT_%d", precision);
2138 TYPE_NAME (t) = get_identifier (type_name);
2144 /* Return a data type that has machine mode MODE. UNSIGNEDP selects
2145 an unsigned type; otherwise a signed type is returned. */
2148 gnat_type_for_mode (enum machine_mode mode, int unsignedp)
2150 if (mode == BLKmode)
2152 else if (mode == VOIDmode)
2153 return void_type_node;
2154 else if (COMPLEX_MODE_P (mode))
2156 else if (SCALAR_FLOAT_MODE_P (mode))
2157 return float_type_for_precision (GET_MODE_PRECISION (mode), mode);
2158 else if (SCALAR_INT_MODE_P (mode))
2159 return gnat_type_for_size (GET_MODE_BITSIZE (mode), unsignedp);
2164 /* Return the unsigned version of a TYPE_NODE, a scalar type. */
2167 gnat_unsigned_type (tree type_node)
2169 tree type = gnat_type_for_size (TYPE_PRECISION (type_node), 1);
2171 if (TREE_CODE (type_node) == INTEGER_TYPE && TYPE_MODULAR_P (type_node))
2173 type = copy_node (type);
2174 TREE_TYPE (type) = type_node;
2176 else if (TREE_TYPE (type_node)
2177 && TREE_CODE (TREE_TYPE (type_node)) == INTEGER_TYPE
2178 && TYPE_MODULAR_P (TREE_TYPE (type_node)))
2180 type = copy_node (type);
2181 TREE_TYPE (type) = TREE_TYPE (type_node);
2187 /* Return the signed version of a TYPE_NODE, a scalar type. */
2190 gnat_signed_type (tree type_node)
2192 tree type = gnat_type_for_size (TYPE_PRECISION (type_node), 0);
2194 if (TREE_CODE (type_node) == INTEGER_TYPE && TYPE_MODULAR_P (type_node))
2196 type = copy_node (type);
2197 TREE_TYPE (type) = type_node;
2199 else if (TREE_TYPE (type_node)
2200 && TREE_CODE (TREE_TYPE (type_node)) == INTEGER_TYPE
2201 && TYPE_MODULAR_P (TREE_TYPE (type_node)))
2203 type = copy_node (type);
2204 TREE_TYPE (type) = TREE_TYPE (type_node);
2210 /* Return 1 if the types T1 and T2 are compatible, i.e. if they can be
2211 transparently converted to each other. */
2214 gnat_types_compatible_p (tree t1, tree t2)
2216 enum tree_code code;
2218 /* This is the default criterion. */
2219 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
2222 /* We only check structural equivalence here. */
2223 if ((code = TREE_CODE (t1)) != TREE_CODE (t2))
2226 /* Array types are also compatible if they are constrained and have
2227 the same component type and the same domain. */
2228 if (code == ARRAY_TYPE
2229 && TREE_TYPE (t1) == TREE_TYPE (t2)
2230 && (TYPE_DOMAIN (t1) == TYPE_DOMAIN (t2)
2231 || (TYPE_DOMAIN (t1)
2233 && tree_int_cst_equal (TYPE_MIN_VALUE (TYPE_DOMAIN (t1)),
2234 TYPE_MIN_VALUE (TYPE_DOMAIN (t2)))
2235 && tree_int_cst_equal (TYPE_MAX_VALUE (TYPE_DOMAIN (t1)),
2236 TYPE_MAX_VALUE (TYPE_DOMAIN (t2))))))
2239 /* Padding record types are also compatible if they pad the same
2240 type and have the same constant size. */
2241 if (code == RECORD_TYPE
2242 && TYPE_IS_PADDING_P (t1) && TYPE_IS_PADDING_P (t2)
2243 && TREE_TYPE (TYPE_FIELDS (t1)) == TREE_TYPE (TYPE_FIELDS (t2))
2244 && tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2)))
2250 /* EXP is an expression for the size of an object. If this size contains
2251 discriminant references, replace them with the maximum (if MAX_P) or
2252 minimum (if !MAX_P) possible value of the discriminant. */
2255 max_size (tree exp, bool max_p)
2257 enum tree_code code = TREE_CODE (exp);
2258 tree type = TREE_TYPE (exp);
2260 switch (TREE_CODE_CLASS (code))
2262 case tcc_declaration:
2267 if (code == CALL_EXPR)
2270 int i, n = call_expr_nargs (exp);
2273 argarray = (tree *) alloca (n * sizeof (tree));
2274 for (i = 0; i < n; i++)
2275 argarray[i] = max_size (CALL_EXPR_ARG (exp, i), max_p);
2276 return build_call_array (type, CALL_EXPR_FN (exp), n, argarray);
2281 /* If this contains a PLACEHOLDER_EXPR, it is the thing we want to
2282 modify. Otherwise, we treat it like a variable. */
2283 if (!CONTAINS_PLACEHOLDER_P (exp))
2286 type = TREE_TYPE (TREE_OPERAND (exp, 1));
2288 max_size (max_p ? TYPE_MAX_VALUE (type) : TYPE_MIN_VALUE (type), true);
2290 case tcc_comparison:
2291 return max_p ? size_one_node : size_zero_node;
2295 case tcc_expression:
2296 switch (TREE_CODE_LENGTH (code))
2299 if (code == NON_LVALUE_EXPR)
2300 return max_size (TREE_OPERAND (exp, 0), max_p);
2303 fold_build1 (code, type,
2304 max_size (TREE_OPERAND (exp, 0),
2305 code == NEGATE_EXPR ? !max_p : max_p));
2308 if (code == COMPOUND_EXPR)
2309 return max_size (TREE_OPERAND (exp, 1), max_p);
2311 /* Calculate "(A ? B : C) - D" as "A ? B - D : C - D" which
2312 may provide a tighter bound on max_size. */
2313 if (code == MINUS_EXPR
2314 && TREE_CODE (TREE_OPERAND (exp, 0)) == COND_EXPR)
2316 tree lhs = fold_build2 (MINUS_EXPR, type,
2317 TREE_OPERAND (TREE_OPERAND (exp, 0), 1),
2318 TREE_OPERAND (exp, 1));
2319 tree rhs = fold_build2 (MINUS_EXPR, type,
2320 TREE_OPERAND (TREE_OPERAND (exp, 0), 2),
2321 TREE_OPERAND (exp, 1));
2322 return fold_build2 (max_p ? MAX_EXPR : MIN_EXPR, type,
2323 max_size (lhs, max_p),
2324 max_size (rhs, max_p));
2328 tree lhs = max_size (TREE_OPERAND (exp, 0), max_p);
2329 tree rhs = max_size (TREE_OPERAND (exp, 1),
2330 code == MINUS_EXPR ? !max_p : max_p);
2332 /* Special-case wanting the maximum value of a MIN_EXPR.
2333 In that case, if one side overflows, return the other.
2334 sizetype is signed, but we know sizes are non-negative.
2335 Likewise, handle a MINUS_EXPR or PLUS_EXPR with the LHS
2336 overflowing or the maximum possible value and the RHS
2340 && TREE_CODE (rhs) == INTEGER_CST
2341 && TREE_OVERFLOW (rhs))
2345 && TREE_CODE (lhs) == INTEGER_CST
2346 && TREE_OVERFLOW (lhs))
2348 else if ((code == MINUS_EXPR || code == PLUS_EXPR)
2349 && ((TREE_CODE (lhs) == INTEGER_CST
2350 && TREE_OVERFLOW (lhs))
2351 || operand_equal_p (lhs, TYPE_MAX_VALUE (type), 0))
2352 && !TREE_CONSTANT (rhs))
2355 return fold_build2 (code, type, lhs, rhs);
2359 if (code == SAVE_EXPR)
2361 else if (code == COND_EXPR)
2362 return fold_build2 (max_p ? MAX_EXPR : MIN_EXPR, type,
2363 max_size (TREE_OPERAND (exp, 1), max_p),
2364 max_size (TREE_OPERAND (exp, 2), max_p));
2367 /* Other tree classes cannot happen. */
2375 /* Build a template of type TEMPLATE_TYPE from the array bounds of ARRAY_TYPE.
2376 EXPR is an expression that we can use to locate any PLACEHOLDER_EXPRs.
2377 Return a constructor for the template. */
2380 build_template (tree template_type, tree array_type, tree expr)
2382 tree template_elts = NULL_TREE;
2383 tree bound_list = NULL_TREE;
2386 while (TREE_CODE (array_type) == RECORD_TYPE
2387 && (TYPE_IS_PADDING_P (array_type)
2388 || TYPE_JUSTIFIED_MODULAR_P (array_type)))
2389 array_type = TREE_TYPE (TYPE_FIELDS (array_type));
2391 if (TREE_CODE (array_type) == ARRAY_TYPE
2392 || (TREE_CODE (array_type) == INTEGER_TYPE
2393 && TYPE_HAS_ACTUAL_BOUNDS_P (array_type)))
2394 bound_list = TYPE_ACTUAL_BOUNDS (array_type);
2396 /* First make the list for a CONSTRUCTOR for the template. Go down the
2397 field list of the template instead of the type chain because this
2398 array might be an Ada array of arrays and we can't tell where the
2399 nested arrays stop being the underlying object. */
2401 for (field = TYPE_FIELDS (template_type); field;
2403 ? (bound_list = TREE_CHAIN (bound_list))
2404 : (array_type = TREE_TYPE (array_type))),
2405 field = TREE_CHAIN (TREE_CHAIN (field)))
2407 tree bounds, min, max;
2409 /* If we have a bound list, get the bounds from there. Likewise
2410 for an ARRAY_TYPE. Otherwise, if expr is a PARM_DECL with
2411 DECL_BY_COMPONENT_PTR_P, use the bounds of the field in the template.
2412 This will give us a maximum range. */
2414 bounds = TREE_VALUE (bound_list);
2415 else if (TREE_CODE (array_type) == ARRAY_TYPE)
2416 bounds = TYPE_INDEX_TYPE (TYPE_DOMAIN (array_type));
2417 else if (expr && TREE_CODE (expr) == PARM_DECL
2418 && DECL_BY_COMPONENT_PTR_P (expr))
2419 bounds = TREE_TYPE (field);
2423 min = convert (TREE_TYPE (field), TYPE_MIN_VALUE (bounds));
2424 max = convert (TREE_TYPE (TREE_CHAIN (field)), TYPE_MAX_VALUE (bounds));
2426 /* If either MIN or MAX involve a PLACEHOLDER_EXPR, we must
2427 substitute it from OBJECT. */
2428 min = SUBSTITUTE_PLACEHOLDER_IN_EXPR (min, expr);
2429 max = SUBSTITUTE_PLACEHOLDER_IN_EXPR (max, expr);
2431 template_elts = tree_cons (TREE_CHAIN (field), max,
2432 tree_cons (field, min, template_elts));
2435 return gnat_build_constructor (template_type, nreverse (template_elts));
2438 /* Build a 32bit VMS descriptor from a Mechanism_Type, which must specify
2439 a descriptor type, and the GCC type of an object. Each FIELD_DECL
2440 in the type contains in its DECL_INITIAL the expression to use when
2441 a constructor is made for the type. GNAT_ENTITY is an entity used
2442 to print out an error message if the mechanism cannot be applied to
2443 an object of that type and also for the name. */
2446 build_vms_descriptor32 (tree type, Mechanism_Type mech, Entity_Id gnat_entity)
2448 tree record_type = make_node (RECORD_TYPE);
2449 tree pointer32_type;
2450 tree field_list = 0;
2459 /* If TYPE is an unconstrained array, use the underlying array type. */
2460 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
2461 type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type))));
2463 /* If this is an array, compute the number of dimensions in the array,
2464 get the index types, and point to the inner type. */
2465 if (TREE_CODE (type) != ARRAY_TYPE)
2468 for (ndim = 1, inner_type = type;
2469 TREE_CODE (TREE_TYPE (inner_type)) == ARRAY_TYPE
2470 && TYPE_MULTI_ARRAY_P (TREE_TYPE (inner_type));
2471 ndim++, inner_type = TREE_TYPE (inner_type))
2474 idx_arr = (tree *) alloca (ndim * sizeof (tree));
2476 if (mech != By_Descriptor_NCA && mech != By_Short_Descriptor_NCA
2477 && TREE_CODE (type) == ARRAY_TYPE && TYPE_CONVENTION_FORTRAN_P (type))
2478 for (i = ndim - 1, inner_type = type;
2480 i--, inner_type = TREE_TYPE (inner_type))
2481 idx_arr[i] = TYPE_DOMAIN (inner_type);
2483 for (i = 0, inner_type = type;
2485 i++, inner_type = TREE_TYPE (inner_type))
2486 idx_arr[i] = TYPE_DOMAIN (inner_type);
2488 /* Now get the DTYPE value. */
2489 switch (TREE_CODE (type))
2494 if (TYPE_VAX_FLOATING_POINT_P (type))
2495 switch (tree_low_cst (TYPE_DIGITS_VALUE (type), 1))
2508 switch (GET_MODE_BITSIZE (TYPE_MODE (type)))
2511 dtype = TYPE_UNSIGNED (type) ? 2 : 6;
2514 dtype = TYPE_UNSIGNED (type) ? 3 : 7;
2517 dtype = TYPE_UNSIGNED (type) ? 4 : 8;
2520 dtype = TYPE_UNSIGNED (type) ? 5 : 9;
2523 dtype = TYPE_UNSIGNED (type) ? 25 : 26;
2529 dtype = GET_MODE_BITSIZE (TYPE_MODE (type)) == 32 ? 52 : 53;
2533 if (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
2534 && TYPE_VAX_FLOATING_POINT_P (type))
2535 switch (tree_low_cst (TYPE_DIGITS_VALUE (type), 1))
2547 dtype = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) == 32 ? 54: 55;
2558 /* Get the CLASS value. */
2561 case By_Descriptor_A:
2562 case By_Short_Descriptor_A:
2565 case By_Descriptor_NCA:
2566 case By_Short_Descriptor_NCA:
2569 case By_Descriptor_SB:
2570 case By_Short_Descriptor_SB:
2574 case By_Short_Descriptor:
2575 case By_Descriptor_S:
2576 case By_Short_Descriptor_S:
2582 /* Make the type for a descriptor for VMS. The first four fields
2583 are the same for all types. */
2586 = chainon (field_list,
2587 make_descriptor_field
2588 ("LENGTH", gnat_type_for_size (16, 1), record_type,
2589 size_in_bytes ((mech == By_Descriptor_A ||
2590 mech == By_Short_Descriptor_A)
2591 ? inner_type : type)));
2593 field_list = chainon (field_list,
2594 make_descriptor_field ("DTYPE",
2595 gnat_type_for_size (8, 1),
2596 record_type, size_int (dtype)));
2597 field_list = chainon (field_list,
2598 make_descriptor_field ("CLASS",
2599 gnat_type_for_size (8, 1),
2600 record_type, size_int (class)));
2602 /* Of course this will crash at run-time if the address space is not
2603 within the low 32 bits, but there is nothing else we can do. */
2604 pointer32_type = build_pointer_type_for_mode (type, SImode, false);
2607 = chainon (field_list,
2608 make_descriptor_field
2609 ("POINTER", pointer32_type, record_type,
2610 build_unary_op (ADDR_EXPR,
2612 build0 (PLACEHOLDER_EXPR, type))));
2617 case By_Short_Descriptor:
2618 case By_Descriptor_S:
2619 case By_Short_Descriptor_S:
2622 case By_Descriptor_SB:
2623 case By_Short_Descriptor_SB:
2625 = chainon (field_list,
2626 make_descriptor_field
2627 ("SB_L1", gnat_type_for_size (32, 1), record_type,
2628 TREE_CODE (type) == ARRAY_TYPE
2629 ? TYPE_MIN_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2631 = chainon (field_list,
2632 make_descriptor_field
2633 ("SB_U1", gnat_type_for_size (32, 1), record_type,
2634 TREE_CODE (type) == ARRAY_TYPE
2635 ? TYPE_MAX_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2638 case By_Descriptor_A:
2639 case By_Short_Descriptor_A:
2640 case By_Descriptor_NCA:
2641 case By_Short_Descriptor_NCA:
2642 field_list = chainon (field_list,
2643 make_descriptor_field ("SCALE",
2644 gnat_type_for_size (8, 1),
2648 field_list = chainon (field_list,
2649 make_descriptor_field ("DIGITS",
2650 gnat_type_for_size (8, 1),
2655 = chainon (field_list,
2656 make_descriptor_field
2657 ("AFLAGS", gnat_type_for_size (8, 1), record_type,
2658 size_int ((mech == By_Descriptor_NCA ||
2659 mech == By_Short_Descriptor_NCA)
2661 /* Set FL_COLUMN, FL_COEFF, and FL_BOUNDS. */
2662 : (TREE_CODE (type) == ARRAY_TYPE
2663 && TYPE_CONVENTION_FORTRAN_P (type)
2666 field_list = chainon (field_list,
2667 make_descriptor_field ("DIMCT",
2668 gnat_type_for_size (8, 1),
2672 field_list = chainon (field_list,
2673 make_descriptor_field ("ARSIZE",
2674 gnat_type_for_size (32, 1),
2676 size_in_bytes (type)));
2678 /* Now build a pointer to the 0,0,0... element. */
2679 tem = build0 (PLACEHOLDER_EXPR, type);
2680 for (i = 0, inner_type = type; i < ndim;
2681 i++, inner_type = TREE_TYPE (inner_type))
2682 tem = build4 (ARRAY_REF, TREE_TYPE (inner_type), tem,
2683 convert (TYPE_DOMAIN (inner_type), size_zero_node),
2684 NULL_TREE, NULL_TREE);
2687 = chainon (field_list,
2688 make_descriptor_field
2690 build_pointer_type_for_mode (inner_type, SImode, false),
2693 build_pointer_type_for_mode (inner_type, SImode,
2697 /* Next come the addressing coefficients. */
2698 tem = size_one_node;
2699 for (i = 0; i < ndim; i++)
2703 = size_binop (MULT_EXPR, tem,
2704 size_binop (PLUS_EXPR,
2705 size_binop (MINUS_EXPR,
2706 TYPE_MAX_VALUE (idx_arr[i]),
2707 TYPE_MIN_VALUE (idx_arr[i])),
2710 fname[0] = ((mech == By_Descriptor_NCA ||
2711 mech == By_Short_Descriptor_NCA) ? 'S' : 'M');
2712 fname[1] = '0' + i, fname[2] = 0;
2714 = chainon (field_list,
2715 make_descriptor_field (fname,
2716 gnat_type_for_size (32, 1),
2717 record_type, idx_length));
2719 if (mech == By_Descriptor_NCA || mech == By_Short_Descriptor_NCA)
2723 /* Finally here are the bounds. */
2724 for (i = 0; i < ndim; i++)
2728 fname[0] = 'L', fname[1] = '0' + i, fname[2] = 0;
2730 = chainon (field_list,
2731 make_descriptor_field
2732 (fname, gnat_type_for_size (32, 1), record_type,
2733 TYPE_MIN_VALUE (idx_arr[i])));
2737 = chainon (field_list,
2738 make_descriptor_field
2739 (fname, gnat_type_for_size (32, 1), record_type,
2740 TYPE_MAX_VALUE (idx_arr[i])));
2745 post_error ("unsupported descriptor type for &", gnat_entity);
2748 TYPE_NAME (record_type) = create_concat_name (gnat_entity, "DESC");
2749 finish_record_type (record_type, field_list, 0, true);
2753 /* Build a 64bit VMS descriptor from a Mechanism_Type, which must specify
2754 a descriptor type, and the GCC type of an object. Each FIELD_DECL
2755 in the type contains in its DECL_INITIAL the expression to use when
2756 a constructor is made for the type. GNAT_ENTITY is an entity used
2757 to print out an error message if the mechanism cannot be applied to
2758 an object of that type and also for the name. */
2761 build_vms_descriptor (tree type, Mechanism_Type mech, Entity_Id gnat_entity)
2763 tree record64_type = make_node (RECORD_TYPE);
2764 tree pointer64_type;
2765 tree field_list64 = 0;
2774 /* If TYPE is an unconstrained array, use the underlying array type. */
2775 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
2776 type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type))));
2778 /* If this is an array, compute the number of dimensions in the array,
2779 get the index types, and point to the inner type. */
2780 if (TREE_CODE (type) != ARRAY_TYPE)
2783 for (ndim = 1, inner_type = type;
2784 TREE_CODE (TREE_TYPE (inner_type)) == ARRAY_TYPE
2785 && TYPE_MULTI_ARRAY_P (TREE_TYPE (inner_type));
2786 ndim++, inner_type = TREE_TYPE (inner_type))
2789 idx_arr = (tree *) alloca (ndim * sizeof (tree));
2791 if (mech != By_Descriptor_NCA
2792 && TREE_CODE (type) == ARRAY_TYPE && TYPE_CONVENTION_FORTRAN_P (type))
2793 for (i = ndim - 1, inner_type = type;
2795 i--, inner_type = TREE_TYPE (inner_type))
2796 idx_arr[i] = TYPE_DOMAIN (inner_type);
2798 for (i = 0, inner_type = type;
2800 i++, inner_type = TREE_TYPE (inner_type))
2801 idx_arr[i] = TYPE_DOMAIN (inner_type);
2803 /* Now get the DTYPE value. */
2804 switch (TREE_CODE (type))
2809 if (TYPE_VAX_FLOATING_POINT_P (type))
2810 switch (tree_low_cst (TYPE_DIGITS_VALUE (type), 1))
2823 switch (GET_MODE_BITSIZE (TYPE_MODE (type)))
2826 dtype = TYPE_UNSIGNED (type) ? 2 : 6;
2829 dtype = TYPE_UNSIGNED (type) ? 3 : 7;
2832 dtype = TYPE_UNSIGNED (type) ? 4 : 8;
2835 dtype = TYPE_UNSIGNED (type) ? 5 : 9;
2838 dtype = TYPE_UNSIGNED (type) ? 25 : 26;
2844 dtype = GET_MODE_BITSIZE (TYPE_MODE (type)) == 32 ? 52 : 53;
2848 if (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
2849 && TYPE_VAX_FLOATING_POINT_P (type))
2850 switch (tree_low_cst (TYPE_DIGITS_VALUE (type), 1))
2862 dtype = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) == 32 ? 54: 55;
2873 /* Get the CLASS value. */
2876 case By_Descriptor_A:
2879 case By_Descriptor_NCA:
2882 case By_Descriptor_SB:
2886 case By_Descriptor_S:
2892 /* Make the type for a 64bit descriptor for VMS. The first six fields
2893 are the same for all types. */
2895 field_list64 = chainon (field_list64,
2896 make_descriptor_field ("MBO",
2897 gnat_type_for_size (16, 1),
2898 record64_type, size_int (1)));
2900 field_list64 = chainon (field_list64,
2901 make_descriptor_field ("DTYPE",
2902 gnat_type_for_size (8, 1),
2903 record64_type, size_int (dtype)));
2904 field_list64 = chainon (field_list64,
2905 make_descriptor_field ("CLASS",
2906 gnat_type_for_size (8, 1),
2907 record64_type, size_int (class)));
2909 field_list64 = chainon (field_list64,
2910 make_descriptor_field ("MBMO",
2911 gnat_type_for_size (32, 1),
2912 record64_type, ssize_int (-1)));
2915 = chainon (field_list64,
2916 make_descriptor_field
2917 ("LENGTH", gnat_type_for_size (64, 1), record64_type,
2918 size_in_bytes (mech == By_Descriptor_A ? inner_type : type)));
2920 pointer64_type = build_pointer_type_for_mode (type, DImode, false);
2923 = chainon (field_list64,
2924 make_descriptor_field
2925 ("POINTER", pointer64_type, record64_type,
2926 build_unary_op (ADDR_EXPR,
2928 build0 (PLACEHOLDER_EXPR, type))));
2933 case By_Descriptor_S:
2936 case By_Descriptor_SB:
2938 = chainon (field_list64,
2939 make_descriptor_field
2940 ("SB_L1", gnat_type_for_size (64, 1), record64_type,
2941 TREE_CODE (type) == ARRAY_TYPE
2942 ? TYPE_MIN_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2944 = chainon (field_list64,
2945 make_descriptor_field
2946 ("SB_U1", gnat_type_for_size (64, 1), record64_type,
2947 TREE_CODE (type) == ARRAY_TYPE
2948 ? TYPE_MAX_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2951 case By_Descriptor_A:
2952 case By_Descriptor_NCA:
2953 field_list64 = chainon (field_list64,
2954 make_descriptor_field ("SCALE",
2955 gnat_type_for_size (8, 1),
2959 field_list64 = chainon (field_list64,
2960 make_descriptor_field ("DIGITS",
2961 gnat_type_for_size (8, 1),
2966 = chainon (field_list64,
2967 make_descriptor_field
2968 ("AFLAGS", gnat_type_for_size (8, 1), record64_type,
2969 size_int (mech == By_Descriptor_NCA
2971 /* Set FL_COLUMN, FL_COEFF, and FL_BOUNDS. */
2972 : (TREE_CODE (type) == ARRAY_TYPE
2973 && TYPE_CONVENTION_FORTRAN_P (type)
2976 field_list64 = chainon (field_list64,
2977 make_descriptor_field ("DIMCT",
2978 gnat_type_for_size (8, 1),
2982 field_list64 = chainon (field_list64,
2983 make_descriptor_field ("MBZ",
2984 gnat_type_for_size (32, 1),
2987 field_list64 = chainon (field_list64,
2988 make_descriptor_field ("ARSIZE",
2989 gnat_type_for_size (64, 1),
2991 size_in_bytes (type)));
2993 /* Now build a pointer to the 0,0,0... element. */
2994 tem = build0 (PLACEHOLDER_EXPR, type);
2995 for (i = 0, inner_type = type; i < ndim;
2996 i++, inner_type = TREE_TYPE (inner_type))
2997 tem = build4 (ARRAY_REF, TREE_TYPE (inner_type), tem,
2998 convert (TYPE_DOMAIN (inner_type), size_zero_node),
2999 NULL_TREE, NULL_TREE);
3002 = chainon (field_list64,
3003 make_descriptor_field
3005 build_pointer_type_for_mode (inner_type, DImode, false),
3008 build_pointer_type_for_mode (inner_type, DImode,
3012 /* Next come the addressing coefficients. */
3013 tem = size_one_node;
3014 for (i = 0; i < ndim; i++)
3018 = size_binop (MULT_EXPR, tem,
3019 size_binop (PLUS_EXPR,
3020 size_binop (MINUS_EXPR,
3021 TYPE_MAX_VALUE (idx_arr[i]),
3022 TYPE_MIN_VALUE (idx_arr[i])),
3025 fname[0] = (mech == By_Descriptor_NCA ? 'S' : 'M');
3026 fname[1] = '0' + i, fname[2] = 0;
3028 = chainon (field_list64,
3029 make_descriptor_field (fname,
3030 gnat_type_for_size (64, 1),
3031 record64_type, idx_length));
3033 if (mech == By_Descriptor_NCA)
3037 /* Finally here are the bounds. */
3038 for (i = 0; i < ndim; i++)
3042 fname[0] = 'L', fname[1] = '0' + i, fname[2] = 0;
3044 = chainon (field_list64,
3045 make_descriptor_field
3046 (fname, gnat_type_for_size (64, 1), record64_type,
3047 TYPE_MIN_VALUE (idx_arr[i])));
3051 = chainon (field_list64,
3052 make_descriptor_field
3053 (fname, gnat_type_for_size (64, 1), record64_type,
3054 TYPE_MAX_VALUE (idx_arr[i])));
3059 post_error ("unsupported descriptor type for &", gnat_entity);
3062 TYPE_NAME (record64_type) = create_concat_name (gnat_entity, "DESC64");
3063 finish_record_type (record64_type, field_list64, 0, true);
3064 return record64_type;
3067 /* Utility routine for above code to make a field. */
3070 make_descriptor_field (const char *name, tree type,
3071 tree rec_type, tree initial)
3074 = create_field_decl (get_identifier (name), type, rec_type, 0, 0, 0, 0);
3076 DECL_INITIAL (field) = initial;
3080 /* Convert GNU_EXPR, a pointer to a 64bit VMS descriptor, to GNU_TYPE, a
3081 regular pointer or fat pointer type. GNAT_SUBPROG is the subprogram to
3082 which the VMS descriptor is passed. */
3085 convert_vms_descriptor64 (tree gnu_type, tree gnu_expr, Entity_Id gnat_subprog)
3087 tree desc_type = TREE_TYPE (TREE_TYPE (gnu_expr));
3088 tree desc = build1 (INDIRECT_REF, desc_type, gnu_expr);
3089 /* The CLASS field is the 3rd field in the descriptor. */
3090 tree class = TREE_CHAIN (TREE_CHAIN (TYPE_FIELDS (desc_type)));
3091 /* The POINTER field is the 6th field in the descriptor. */
3092 tree pointer64 = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (class)));
3094 /* Retrieve the value of the POINTER field. */
3096 = build3 (COMPONENT_REF, TREE_TYPE (pointer64), desc, pointer64, NULL_TREE);
3098 if (POINTER_TYPE_P (gnu_type))
3099 return convert (gnu_type, gnu_expr64);
3101 else if (TYPE_FAT_POINTER_P (gnu_type))
3103 tree p_array_type = TREE_TYPE (TYPE_FIELDS (gnu_type));
3104 tree p_bounds_type = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type)));
3105 tree template_type = TREE_TYPE (p_bounds_type);
3106 tree min_field = TYPE_FIELDS (template_type);
3107 tree max_field = TREE_CHAIN (TYPE_FIELDS (template_type));
3108 tree template, template_addr, aflags, dimct, t, u;
3109 /* See the head comment of build_vms_descriptor. */
3110 int iclass = TREE_INT_CST_LOW (DECL_INITIAL (class));
3111 tree lfield, ufield;
3113 /* Convert POINTER to the type of the P_ARRAY field. */
3114 gnu_expr64 = convert (p_array_type, gnu_expr64);
3118 case 1: /* Class S */
3119 case 15: /* Class SB */
3120 /* Build {1, LENGTH} template; LENGTH64 is the 5th field. */
3121 t = TREE_CHAIN (TREE_CHAIN (class));
3122 t = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3123 t = tree_cons (min_field,
3124 convert (TREE_TYPE (min_field), integer_one_node),
3125 tree_cons (max_field,
3126 convert (TREE_TYPE (max_field), t),
3128 template = gnat_build_constructor (template_type, t);
3129 template_addr = build_unary_op (ADDR_EXPR, NULL_TREE, template);
3131 /* For class S, we are done. */
3135 /* Test that we really have a SB descriptor, like DEC Ada. */
3136 t = build3 (COMPONENT_REF, TREE_TYPE (class), desc, class, NULL);
3137 u = convert (TREE_TYPE (class), DECL_INITIAL (class));
3138 u = build_binary_op (EQ_EXPR, integer_type_node, t, u);
3139 /* If so, there is already a template in the descriptor and
3140 it is located right after the POINTER field. The fields are
3141 64bits so they must be repacked. */
3142 t = TREE_CHAIN (pointer64);
3143 lfield = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3144 lfield = convert (TREE_TYPE (TYPE_FIELDS (template_type)), lfield);
3147 ufield = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3149 (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (template_type))), ufield);
3151 /* Build the template in the form of a constructor. */
3152 t = tree_cons (TYPE_FIELDS (template_type), lfield,
3153 tree_cons (TREE_CHAIN (TYPE_FIELDS (template_type)),
3154 ufield, NULL_TREE));
3155 template = gnat_build_constructor (template_type, t);
3157 /* Otherwise use the {1, LENGTH} template we build above. */
3158 template_addr = build3 (COND_EXPR, p_bounds_type, u,
3159 build_unary_op (ADDR_EXPR, p_bounds_type,
3164 case 4: /* Class A */
3165 /* The AFLAGS field is the 3rd field after the pointer in the
3167 t = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (pointer64)));
3168 aflags = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3169 /* The DIMCT field is the next field in the descriptor after
3172 dimct = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3173 /* Raise CONSTRAINT_ERROR if either more than 1 dimension
3174 or FL_COEFF or FL_BOUNDS not set. */
3175 u = build_int_cst (TREE_TYPE (aflags), 192);
3176 u = build_binary_op (TRUTH_OR_EXPR, integer_type_node,
3177 build_binary_op (NE_EXPR, integer_type_node,
3179 convert (TREE_TYPE (dimct),
3181 build_binary_op (NE_EXPR, integer_type_node,
3182 build2 (BIT_AND_EXPR,
3186 /* There is already a template in the descriptor and it is located
3187 in block 3. The fields are 64bits so they must be repacked. */
3188 t = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN
3190 lfield = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3191 lfield = convert (TREE_TYPE (TYPE_FIELDS (template_type)), lfield);
3194 ufield = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3196 (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (template_type))), ufield);
3198 /* Build the template in the form of a constructor. */
3199 t = tree_cons (TYPE_FIELDS (template_type), lfield,
3200 tree_cons (TREE_CHAIN (TYPE_FIELDS (template_type)),
3201 ufield, NULL_TREE));
3202 template = gnat_build_constructor (template_type, t);
3203 template = build3 (COND_EXPR, p_bounds_type, u,
3204 build_call_raise (CE_Length_Check_Failed, Empty,
3205 N_Raise_Constraint_Error),
3207 template_addr = build_unary_op (ADDR_EXPR, p_bounds_type, template);
3210 case 10: /* Class NCA */
3212 post_error ("unsupported descriptor type for &", gnat_subprog);
3213 template_addr = integer_zero_node;
3217 /* Build the fat pointer in the form of a constructor. */
3218 t = tree_cons (TYPE_FIELDS (gnu_type), gnu_expr64,
3219 tree_cons (TREE_CHAIN (TYPE_FIELDS (gnu_type)),
3220 template_addr, NULL_TREE));
3221 return gnat_build_constructor (gnu_type, t);
3228 /* Convert GNU_EXPR, a pointer to a 32bit VMS descriptor, to GNU_TYPE, a
3229 regular pointer or fat pointer type. GNAT_SUBPROG is the subprogram to
3230 which the VMS descriptor is passed. */
3233 convert_vms_descriptor32 (tree gnu_type, tree gnu_expr, Entity_Id gnat_subprog)
3235 tree desc_type = TREE_TYPE (TREE_TYPE (gnu_expr));
3236 tree desc = build1 (INDIRECT_REF, desc_type, gnu_expr);
3237 /* The CLASS field is the 3rd field in the descriptor. */
3238 tree class = TREE_CHAIN (TREE_CHAIN (TYPE_FIELDS (desc_type)));
3239 /* The POINTER field is the 4th field in the descriptor. */
3240 tree pointer = TREE_CHAIN (class);
3242 /* Retrieve the value of the POINTER field. */
3244 = build3 (COMPONENT_REF, TREE_TYPE (pointer), desc, pointer, NULL_TREE);
3246 if (POINTER_TYPE_P (gnu_type))
3247 return convert (gnu_type, gnu_expr32);
3249 else if (TYPE_FAT_POINTER_P (gnu_type))
3251 tree p_array_type = TREE_TYPE (TYPE_FIELDS (gnu_type));
3252 tree p_bounds_type = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type)));
3253 tree template_type = TREE_TYPE (p_bounds_type);
3254 tree min_field = TYPE_FIELDS (template_type);
3255 tree max_field = TREE_CHAIN (TYPE_FIELDS (template_type));
3256 tree template, template_addr, aflags, dimct, t, u;
3257 /* See the head comment of build_vms_descriptor. */
3258 int iclass = TREE_INT_CST_LOW (DECL_INITIAL (class));
3260 /* Convert POINTER to the type of the P_ARRAY field. */
3261 gnu_expr32 = convert (p_array_type, gnu_expr32);
3265 case 1: /* Class S */
3266 case 15: /* Class SB */
3267 /* Build {1, LENGTH} template; LENGTH is the 1st field. */
3268 t = TYPE_FIELDS (desc_type);
3269 t = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3270 t = tree_cons (min_field,
3271 convert (TREE_TYPE (min_field), integer_one_node),
3272 tree_cons (max_field,
3273 convert (TREE_TYPE (max_field), t),
3275 template = gnat_build_constructor (template_type, t);
3276 template_addr = build_unary_op (ADDR_EXPR, NULL_TREE, template);
3278 /* For class S, we are done. */
3282 /* Test that we really have a SB descriptor, like DEC Ada. */
3283 t = build3 (COMPONENT_REF, TREE_TYPE (class), desc, class, NULL);
3284 u = convert (TREE_TYPE (class), DECL_INITIAL (class));
3285 u = build_binary_op (EQ_EXPR, integer_type_node, t, u);
3286 /* If so, there is already a template in the descriptor and
3287 it is located right after the POINTER field. */
3288 t = TREE_CHAIN (pointer);
3289 template = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3290 /* Otherwise use the {1, LENGTH} template we build above. */
3291 template_addr = build3 (COND_EXPR, p_bounds_type, u,
3292 build_unary_op (ADDR_EXPR, p_bounds_type,
3297 case 4: /* Class A */
3298 /* The AFLAGS field is the 7th field in the descriptor. */
3299 t = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (pointer)));
3300 aflags = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3301 /* The DIMCT field is the 8th field in the descriptor. */
3303 dimct = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3304 /* Raise CONSTRAINT_ERROR if either more than 1 dimension
3305 or FL_COEFF or FL_BOUNDS not set. */
3306 u = build_int_cst (TREE_TYPE (aflags), 192);
3307 u = build_binary_op (TRUTH_OR_EXPR, integer_type_node,
3308 build_binary_op (NE_EXPR, integer_type_node,
3310 convert (TREE_TYPE (dimct),
3312 build_binary_op (NE_EXPR, integer_type_node,
3313 build2 (BIT_AND_EXPR,
3317 /* There is already a template in the descriptor and it is
3318 located at the start of block 3 (12th field). */
3319 t = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (t))));
3320 template = build3 (COMPONENT_REF, TREE_TYPE (t), desc, t, NULL_TREE);
3321 template = build3 (COND_EXPR, p_bounds_type, u,
3322 build_call_raise (CE_Length_Check_Failed, Empty,
3323 N_Raise_Constraint_Error),
3325 template_addr = build_unary_op (ADDR_EXPR, p_bounds_type, template);
3328 case 10: /* Class NCA */
3330 post_error ("unsupported descriptor type for &", gnat_subprog);
3331 template_addr = integer_zero_node;
3335 /* Build the fat pointer in the form of a constructor. */
3336 t = tree_cons (TYPE_FIELDS (gnu_type), gnu_expr32,
3337 tree_cons (TREE_CHAIN (TYPE_FIELDS (gnu_type)),
3338 template_addr, NULL_TREE));
3340 return gnat_build_constructor (gnu_type, t);
3347 /* Convert GNU_EXPR, a pointer to a VMS descriptor, to GNU_TYPE, a regular
3348 pointer or fat pointer type. GNU_EXPR_ALT_TYPE is the alternate (32-bit)
3349 pointer type of GNU_EXPR. GNAT_SUBPROG is the subprogram to which the
3350 VMS descriptor is passed. */
3353 convert_vms_descriptor (tree gnu_type, tree gnu_expr, tree gnu_expr_alt_type,
3354 Entity_Id gnat_subprog)
3356 tree desc_type = TREE_TYPE (TREE_TYPE (gnu_expr));
3357 tree desc = build1 (INDIRECT_REF, desc_type, gnu_expr);
3358 tree mbo = TYPE_FIELDS (desc_type);
3359 const char *mbostr = IDENTIFIER_POINTER (DECL_NAME (mbo));
3360 tree mbmo = TREE_CHAIN (TREE_CHAIN (TREE_CHAIN (mbo)));
3361 tree is64bit, gnu_expr32, gnu_expr64;
3363 /* If the field name is not MBO, it must be 32-bit and no alternate.
3364 Otherwise primary must be 64-bit and alternate 32-bit. */
3365 if (strcmp (mbostr, "MBO") != 0)
3366 return convert_vms_descriptor32 (gnu_type, gnu_expr, gnat_subprog);
3368 /* Build the test for 64-bit descriptor. */
3369 mbo = build3 (COMPONENT_REF, TREE_TYPE (mbo), desc, mbo, NULL_TREE);
3370 mbmo = build3 (COMPONENT_REF, TREE_TYPE (mbmo), desc, mbmo, NULL_TREE);
3372 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
3373 build_binary_op (EQ_EXPR, integer_type_node,
3374 convert (integer_type_node, mbo),
3376 build_binary_op (EQ_EXPR, integer_type_node,
3377 convert (integer_type_node, mbmo),
3378 integer_minus_one_node));
3380 /* Build the 2 possible end results. */
3381 gnu_expr64 = convert_vms_descriptor64 (gnu_type, gnu_expr, gnat_subprog);
3382 gnu_expr = fold_convert (gnu_expr_alt_type, gnu_expr);
3383 gnu_expr32 = convert_vms_descriptor32 (gnu_type, gnu_expr, gnat_subprog);
3385 return build3 (COND_EXPR, gnu_type, is64bit, gnu_expr64, gnu_expr32);
3388 /* Build a stub for the subprogram specified by the GCC tree GNU_SUBPROG
3389 and the GNAT node GNAT_SUBPROG. */
3392 build_function_stub (tree gnu_subprog, Entity_Id gnat_subprog)
3394 tree gnu_subprog_type, gnu_subprog_addr, gnu_subprog_call;
3395 tree gnu_stub_param, gnu_param_list, gnu_arg_types, gnu_param;
3396 tree gnu_stub_decl = DECL_FUNCTION_STUB (gnu_subprog);
3399 gnu_subprog_type = TREE_TYPE (gnu_subprog);
3400 gnu_param_list = NULL_TREE;
3402 begin_subprog_body (gnu_stub_decl);
3405 start_stmt_group ();
3407 /* Loop over the parameters of the stub and translate any of them
3408 passed by descriptor into a by reference one. */
3409 for (gnu_stub_param = DECL_ARGUMENTS (gnu_stub_decl),
3410 gnu_arg_types = TYPE_ARG_TYPES (gnu_subprog_type);
3412 gnu_stub_param = TREE_CHAIN (gnu_stub_param),
3413 gnu_arg_types = TREE_CHAIN (gnu_arg_types))
3415 if (DECL_BY_DESCRIPTOR_P (gnu_stub_param))
3417 = convert_vms_descriptor (TREE_VALUE (gnu_arg_types),
3419 DECL_PARM_ALT_TYPE (gnu_stub_param),
3422 gnu_param = gnu_stub_param;
3424 gnu_param_list = tree_cons (NULL_TREE, gnu_param, gnu_param_list);
3427 gnu_body = end_stmt_group ();
3429 /* Invoke the internal subprogram. */
3430 gnu_subprog_addr = build1 (ADDR_EXPR, build_pointer_type (gnu_subprog_type),
3432 gnu_subprog_call = build_call_list (TREE_TYPE (gnu_subprog_type),
3434 nreverse (gnu_param_list));
3436 /* Propagate the return value, if any. */
3437 if (VOID_TYPE_P (TREE_TYPE (gnu_subprog_type)))
3438 append_to_statement_list (gnu_subprog_call, &gnu_body);
3440 append_to_statement_list (build_return_expr (DECL_RESULT (gnu_stub_decl),
3446 allocate_struct_function (gnu_stub_decl, false);
3447 end_subprog_body (gnu_body, false);
3450 /* Build a type to be used to represent an aliased object whose nominal
3451 type is an unconstrained array. This consists of a RECORD_TYPE containing
3452 a field of TEMPLATE_TYPE and a field of OBJECT_TYPE, which is an
3453 ARRAY_TYPE. If ARRAY_TYPE is that of the unconstrained array, this
3454 is used to represent an arbitrary unconstrained object. Use NAME
3455 as the name of the record. */
3458 build_unc_object_type (tree template_type, tree object_type, tree name)
3460 tree type = make_node (RECORD_TYPE);
3461 tree template_field = create_field_decl (get_identifier ("BOUNDS"),
3462 template_type, type, 0, 0, 0, 1);
3463 tree array_field = create_field_decl (get_identifier ("ARRAY"), object_type,
3466 TYPE_NAME (type) = name;
3467 TYPE_CONTAINS_TEMPLATE_P (type) = 1;
3468 finish_record_type (type,
3469 chainon (chainon (NULL_TREE, template_field),
3476 /* Same, taking a thin or fat pointer type instead of a template type. */
3479 build_unc_object_type_from_ptr (tree thin_fat_ptr_type, tree object_type,
3484 gcc_assert (TYPE_FAT_OR_THIN_POINTER_P (thin_fat_ptr_type));
3487 = (TYPE_FAT_POINTER_P (thin_fat_ptr_type)
3488 ? TREE_TYPE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (thin_fat_ptr_type))))
3489 : TREE_TYPE (TYPE_FIELDS (TREE_TYPE (thin_fat_ptr_type))));
3490 return build_unc_object_type (template_type, object_type, name);
3493 /* Shift the component offsets within an unconstrained object TYPE to make it
3494 suitable for use as a designated type for thin pointers. */
3497 shift_unc_components_for_thin_pointers (tree type)
3499 /* Thin pointer values designate the ARRAY data of an unconstrained object,
3500 allocated past the BOUNDS template. The designated type is adjusted to
3501 have ARRAY at position zero and the template at a negative offset, so
3502 that COMPONENT_REFs on (*thin_ptr) designate the proper location. */
3504 tree bounds_field = TYPE_FIELDS (type);
3505 tree array_field = TREE_CHAIN (TYPE_FIELDS (type));
3507 DECL_FIELD_OFFSET (bounds_field)
3508 = size_binop (MINUS_EXPR, size_zero_node, byte_position (array_field));
3510 DECL_FIELD_OFFSET (array_field) = size_zero_node;
3511 DECL_FIELD_BIT_OFFSET (array_field) = bitsize_zero_node;
3514 /* Update anything previously pointing to OLD_TYPE to point to NEW_TYPE.
3515 In the normal case this is just two adjustments, but we have more to
3516 do if NEW_TYPE is an UNCONSTRAINED_ARRAY_TYPE. */
3519 update_pointer_to (tree old_type, tree new_type)
3521 tree ptr = TYPE_POINTER_TO (old_type);
3522 tree ref = TYPE_REFERENCE_TO (old_type);
3526 /* If this is the main variant, process all the other variants first. */
3527 if (TYPE_MAIN_VARIANT (old_type) == old_type)
3528 for (type = TYPE_NEXT_VARIANT (old_type); type;
3529 type = TYPE_NEXT_VARIANT (type))
3530 update_pointer_to (type, new_type);
3532 /* If no pointers and no references, we are done. */
3536 /* Merge the old type qualifiers in the new type.
3538 Each old variant has qualifiers for specific reasons, and the new
3539 designated type as well. Each set of qualifiers represents useful
3540 information grabbed at some point, and merging the two simply unifies
3541 these inputs into the final type description.
3543 Consider for instance a volatile type frozen after an access to constant
3544 type designating it; after the designated type's freeze, we get here with
3545 a volatile NEW_TYPE and a dummy OLD_TYPE with a readonly variant, created
3546 when the access type was processed. We will make a volatile and readonly
3547 designated type, because that's what it really is.
3549 We might also get here for a non-dummy OLD_TYPE variant with different
3550 qualifiers than those of NEW_TYPE, for instance in some cases of pointers
3551 to private record type elaboration (see the comments around the call to
3552 this routine in gnat_to_gnu_entity <E_Access_Type>). We have to merge
3553 the qualifiers in those cases too, to avoid accidentally discarding the
3554 initial set, and will often end up with OLD_TYPE == NEW_TYPE then. */
3556 = build_qualified_type (new_type,
3557 TYPE_QUALS (old_type) | TYPE_QUALS (new_type));
3559 /* If old type and new type are identical, there is nothing to do. */
3560 if (old_type == new_type)
3563 /* Otherwise, first handle the simple case. */
3564 if (TREE_CODE (new_type) != UNCONSTRAINED_ARRAY_TYPE)
3566 TYPE_POINTER_TO (new_type) = ptr;
3567 TYPE_REFERENCE_TO (new_type) = ref;
3569 for (; ptr; ptr = TYPE_NEXT_PTR_TO (ptr))
3570 for (ptr1 = TYPE_MAIN_VARIANT (ptr); ptr1;
3571 ptr1 = TYPE_NEXT_VARIANT (ptr1))
3572 TREE_TYPE (ptr1) = new_type;
3574 for (; ref; ref = TYPE_NEXT_REF_TO (ref))
3575 for (ref1 = TYPE_MAIN_VARIANT (ref); ref1;
3576 ref1 = TYPE_NEXT_VARIANT (ref1))
3577 TREE_TYPE (ref1) = new_type;
3580 /* Now deal with the unconstrained array case. In this case the "pointer"
3581 is actually a RECORD_TYPE where both fields are pointers to dummy nodes.
3582 Turn them into pointers to the correct types using update_pointer_to. */
3583 else if (!TYPE_FAT_POINTER_P (ptr))
3588 tree new_obj_rec = TYPE_OBJECT_RECORD_TYPE (new_type);
3589 tree array_field = TYPE_FIELDS (ptr);
3590 tree bounds_field = TREE_CHAIN (TYPE_FIELDS (ptr));
3591 tree new_ptr = TYPE_POINTER_TO (new_type);
3595 /* Make pointers to the dummy template point to the real template. */
3597 (TREE_TYPE (TREE_TYPE (bounds_field)),
3598 TREE_TYPE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (new_ptr)))));
3600 /* The references to the template bounds present in the array type
3601 are made through a PLACEHOLDER_EXPR of type NEW_PTR. Since we
3602 are updating PTR to make it a full replacement for NEW_PTR as
3603 pointer to NEW_TYPE, we must rework the PLACEHOLDER_EXPR so as
3604 to make it of type PTR. */
3605 new_ref = build3 (COMPONENT_REF, TREE_TYPE (bounds_field),
3606 build0 (PLACEHOLDER_EXPR, ptr),
3607 bounds_field, NULL_TREE);
3609 /* Create the new array for the new PLACEHOLDER_EXPR and make pointers
3610 to the dummy array point to it. */
3612 (TREE_TYPE (TREE_TYPE (array_field)),
3613 substitute_in_type (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (new_ptr))),
3614 TREE_CHAIN (TYPE_FIELDS (new_ptr)), new_ref));
3616 /* Make PTR the pointer to NEW_TYPE. */
3617 TYPE_POINTER_TO (new_type) = TYPE_REFERENCE_TO (new_type)
3618 = TREE_TYPE (new_type) = ptr;
3620 for (var = TYPE_MAIN_VARIANT (ptr); var; var = TYPE_NEXT_VARIANT (var))
3621 SET_TYPE_UNCONSTRAINED_ARRAY (var, new_type);
3623 /* Now handle updating the allocation record, what the thin pointer
3624 points to. Update all pointers from the old record into the new
3625 one, update the type of the array field, and recompute the size. */
3626 update_pointer_to (TYPE_OBJECT_RECORD_TYPE (old_type), new_obj_rec);
3628 TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (new_obj_rec)))
3629 = TREE_TYPE (TREE_TYPE (array_field));
3631 /* The size recomputation needs to account for alignment constraints, so
3632 we let layout_type work it out. This will reset the field offsets to
3633 what they would be in a regular record, so we shift them back to what
3634 we want them to be for a thin pointer designated type afterwards. */
3635 DECL_SIZE (TYPE_FIELDS (new_obj_rec)) = 0;
3636 DECL_SIZE (TREE_CHAIN (TYPE_FIELDS (new_obj_rec))) = 0;
3637 TYPE_SIZE (new_obj_rec) = 0;
3638 layout_type (new_obj_rec);
3640 shift_unc_components_for_thin_pointers (new_obj_rec);
3642 /* We are done, at last. */
3643 rest_of_record_type_compilation (ptr);
3647 /* Convert EXPR, a pointer to a constrained array, into a pointer to an
3648 unconstrained one. This involves making or finding a template. */
3651 convert_to_fat_pointer (tree type, tree expr)
3653 tree template_type = TREE_TYPE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (type))));
3654 tree p_array_type = TREE_TYPE (TYPE_FIELDS (type));
3655 tree etype = TREE_TYPE (expr);
3658 /* If EXPR is null, make a fat pointer that contains null pointers to the
3659 template and array. */
3660 if (integer_zerop (expr))
3662 gnat_build_constructor
3664 tree_cons (TYPE_FIELDS (type),
3665 convert (p_array_type, expr),
3666 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
3667 convert (build_pointer_type (template_type),
3671 /* If EXPR is a thin pointer, make template and data from the record.. */
3672 else if (TYPE_THIN_POINTER_P (etype))
3674 tree fields = TYPE_FIELDS (TREE_TYPE (etype));
3676 expr = save_expr (expr);
3677 if (TREE_CODE (expr) == ADDR_EXPR)
3678 expr = TREE_OPERAND (expr, 0);
3680 expr = build1 (INDIRECT_REF, TREE_TYPE (etype), expr);
3682 template = build_component_ref (expr, NULL_TREE, fields, false);
3683 expr = build_unary_op (ADDR_EXPR, NULL_TREE,
3684 build_component_ref (expr, NULL_TREE,
3685 TREE_CHAIN (fields), false));
3688 /* Otherwise, build the constructor for the template. */
3690 template = build_template (template_type, TREE_TYPE (etype), expr);
3692 /* The final result is a constructor for the fat pointer.
3694 If EXPR is an argument of a foreign convention subprogram, the type it
3695 points to is directly the component type. In this case, the expression
3696 type may not match the corresponding FIELD_DECL type at this point, so we
3697 call "convert" here to fix that up if necessary. This type consistency is
3698 required, for instance because it ensures that possible later folding of
3699 COMPONENT_REFs against this constructor always yields something of the
3700 same type as the initial reference.
3702 Note that the call to "build_template" above is still fine because it
3703 will only refer to the provided TEMPLATE_TYPE in this case. */
3705 gnat_build_constructor
3707 tree_cons (TYPE_FIELDS (type),
3708 convert (p_array_type, expr),
3709 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
3710 build_unary_op (ADDR_EXPR, NULL_TREE, template),
3714 /* Convert to a thin pointer type, TYPE. The only thing we know how to convert
3715 is something that is a fat pointer, so convert to it first if it EXPR
3716 is not already a fat pointer. */
3719 convert_to_thin_pointer (tree type, tree expr)
3721 if (!TYPE_FAT_POINTER_P (TREE_TYPE (expr)))
3723 = convert_to_fat_pointer
3724 (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))), expr);
3726 /* We get the pointer to the data and use a NOP_EXPR to make it the
3728 expr = build_component_ref (expr, NULL_TREE, TYPE_FIELDS (TREE_TYPE (expr)),
3730 expr = build1 (NOP_EXPR, type, expr);
3735 /* Create an expression whose value is that of EXPR,
3736 converted to type TYPE. The TREE_TYPE of the value
3737 is always TYPE. This function implements all reasonable
3738 conversions; callers should filter out those that are
3739 not permitted by the language being compiled. */
3742 convert (tree type, tree expr)
3744 enum tree_code code = TREE_CODE (type);
3745 tree etype = TREE_TYPE (expr);
3746 enum tree_code ecode = TREE_CODE (etype);
3748 /* If EXPR is already the right type, we are done. */
3752 /* If both input and output have padding and are of variable size, do this
3753 as an unchecked conversion. Likewise if one is a mere variant of the
3754 other, so we avoid a pointless unpad/repad sequence. */
3755 else if (code == RECORD_TYPE && ecode == RECORD_TYPE
3756 && TYPE_IS_PADDING_P (type) && TYPE_IS_PADDING_P (etype)
3757 && (!TREE_CONSTANT (TYPE_SIZE (type))
3758 || !TREE_CONSTANT (TYPE_SIZE (etype))
3759 || gnat_types_compatible_p (type, etype)
3760 || TYPE_NAME (TREE_TYPE (TYPE_FIELDS (type)))
3761 == TYPE_NAME (TREE_TYPE (TYPE_FIELDS (etype)))))
3764 /* If the output type has padding, convert to the inner type and
3765 make a constructor to build the record. */
3766 else if (code == RECORD_TYPE && TYPE_IS_PADDING_P (type))
3768 /* If we previously converted from another type and our type is
3769 of variable size, remove the conversion to avoid the need for
3770 variable-size temporaries. Likewise for a conversion between
3771 original and packable version. */
3772 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3773 && (!TREE_CONSTANT (TYPE_SIZE (type))
3774 || (ecode == RECORD_TYPE
3775 && TYPE_NAME (etype)
3776 == TYPE_NAME (TREE_TYPE (TREE_OPERAND (expr, 0))))))
3777 expr = TREE_OPERAND (expr, 0);
3779 /* If we are just removing the padding from expr, convert the original
3780 object if we have variable size in order to avoid the need for some
3781 variable-size temporaries. Likewise if the padding is a mere variant
3782 of the other, so we avoid a pointless unpad/repad sequence. */
3783 if (TREE_CODE (expr) == COMPONENT_REF
3784 && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE
3785 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (expr, 0)))
3786 && (!TREE_CONSTANT (TYPE_SIZE (type))
3787 || gnat_types_compatible_p (type,
3788 TREE_TYPE (TREE_OPERAND (expr, 0)))
3789 || (ecode == RECORD_TYPE
3790 && TYPE_NAME (etype)
3791 == TYPE_NAME (TREE_TYPE (TYPE_FIELDS (type))))))
3792 return convert (type, TREE_OPERAND (expr, 0));
3794 /* If the result type is a padded type with a self-referentially-sized
3795 field and the expression type is a record, do this as an
3796 unchecked conversion. */
3797 else if (TREE_CODE (etype) == RECORD_TYPE
3798 && CONTAINS_PLACEHOLDER_P (DECL_SIZE (TYPE_FIELDS (type))))
3799 return unchecked_convert (type, expr, false);
3803 gnat_build_constructor (type,
3804 tree_cons (TYPE_FIELDS (type),
3806 (TYPE_FIELDS (type)),
3811 /* If the input type has padding, remove it and convert to the output type.
3812 The conditions ordering is arranged to ensure that the output type is not
3813 a padding type here, as it is not clear whether the conversion would
3814 always be correct if this was to happen. */
3815 else if (ecode == RECORD_TYPE && TYPE_IS_PADDING_P (etype))
3819 /* If we have just converted to this padded type, just get the
3820 inner expression. */
3821 if (TREE_CODE (expr) == CONSTRUCTOR
3822 && !VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (expr))
3823 && VEC_index (constructor_elt, CONSTRUCTOR_ELTS (expr), 0)->index
3824 == TYPE_FIELDS (etype))
3826 = VEC_index (constructor_elt, CONSTRUCTOR_ELTS (expr), 0)->value;
3828 /* Otherwise, build an explicit component reference. */
3831 = build_component_ref (expr, NULL_TREE, TYPE_FIELDS (etype), false);
3833 return convert (type, unpadded);
3836 /* If the input is a biased type, adjust first. */
3837 if (ecode == INTEGER_TYPE && TYPE_BIASED_REPRESENTATION_P (etype))
3838 return convert (type, fold_build2 (PLUS_EXPR, TREE_TYPE (etype),
3839 fold_convert (TREE_TYPE (etype),
3841 TYPE_MIN_VALUE (etype)));
3843 /* If the input is a justified modular type, we need to extract the actual
3844 object before converting it to any other type with the exceptions of an
3845 unconstrained array or of a mere type variant. It is useful to avoid the
3846 extraction and conversion in the type variant case because it could end
3847 up replacing a VAR_DECL expr by a constructor and we might be about the
3848 take the address of the result. */
3849 if (ecode == RECORD_TYPE && TYPE_JUSTIFIED_MODULAR_P (etype)
3850 && code != UNCONSTRAINED_ARRAY_TYPE
3851 && TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (etype))
3852 return convert (type, build_component_ref (expr, NULL_TREE,
3853 TYPE_FIELDS (etype), false));
3855 /* If converting to a type that contains a template, convert to the data
3856 type and then build the template. */
3857 if (code == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (type))
3859 tree obj_type = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (type)));
3861 /* If the source already has a template, get a reference to the
3862 associated array only, as we are going to rebuild a template
3863 for the target type anyway. */
3864 expr = maybe_unconstrained_array (expr);
3867 gnat_build_constructor
3869 tree_cons (TYPE_FIELDS (type),
3870 build_template (TREE_TYPE (TYPE_FIELDS (type)),
3871 obj_type, NULL_TREE),
3872 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
3873 convert (obj_type, expr), NULL_TREE)));
3876 /* There are some special cases of expressions that we process
3878 switch (TREE_CODE (expr))
3884 /* Just set its type here. For TRANSFORM_EXPR, we will do the actual
3885 conversion in gnat_expand_expr. NULL_EXPR does not represent
3886 and actual value, so no conversion is needed. */
3887 expr = copy_node (expr);
3888 TREE_TYPE (expr) = type;
3892 /* If we are converting a STRING_CST to another constrained array type,
3893 just make a new one in the proper type. */
3894 if (code == ecode && AGGREGATE_TYPE_P (etype)
3895 && !(TREE_CODE (TYPE_SIZE (etype)) == INTEGER_CST
3896 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
3898 expr = copy_node (expr);
3899 TREE_TYPE (expr) = type;
3905 /* If we are converting a CONSTRUCTOR to a mere variant type, just make
3906 a new one in the proper type. */
3907 if (code == ecode && gnat_types_compatible_p (type, etype))
3909 expr = copy_node (expr);
3910 TREE_TYPE (expr) = type;
3914 /* Likewise for a conversion between original and packable version, but
3915 we have to work harder in order to preserve type consistency. */
3917 && code == RECORD_TYPE
3918 && TYPE_NAME (type) == TYPE_NAME (etype))
3920 VEC(constructor_elt,gc) *e = CONSTRUCTOR_ELTS (expr);
3921 unsigned HOST_WIDE_INT len = VEC_length (constructor_elt, e);
3922 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, len);
3923 tree efield = TYPE_FIELDS (etype), field = TYPE_FIELDS (type);
3924 unsigned HOST_WIDE_INT idx;
3927 FOR_EACH_CONSTRUCTOR_ELT(e, idx, index, value)
3929 constructor_elt *elt = VEC_quick_push (constructor_elt, v, NULL);
3930 /* We expect only simple constructors. Otherwise, punt. */
3931 if (!(index == efield || index == DECL_ORIGINAL_FIELD (efield)))
3934 elt->value = convert (TREE_TYPE (field), value);
3935 efield = TREE_CHAIN (efield);
3936 field = TREE_CHAIN (field);
3941 expr = copy_node (expr);
3942 TREE_TYPE (expr) = type;
3943 CONSTRUCTOR_ELTS (expr) = v;
3949 case UNCONSTRAINED_ARRAY_REF:
3950 /* Convert this to the type of the inner array by getting the address of
3951 the array from the template. */
3952 expr = build_unary_op (INDIRECT_REF, NULL_TREE,
3953 build_component_ref (TREE_OPERAND (expr, 0),
3954 get_identifier ("P_ARRAY"),
3956 etype = TREE_TYPE (expr);
3957 ecode = TREE_CODE (etype);
3960 case VIEW_CONVERT_EXPR:
3962 /* GCC 4.x is very sensitive to type consistency overall, and view
3963 conversions thus are very frequent. Even though just "convert"ing
3964 the inner operand to the output type is fine in most cases, it
3965 might expose unexpected input/output type mismatches in special
3966 circumstances so we avoid such recursive calls when we can. */
3967 tree op0 = TREE_OPERAND (expr, 0);
3969 /* If we are converting back to the original type, we can just
3970 lift the input conversion. This is a common occurrence with
3971 switches back-and-forth amongst type variants. */
3972 if (type == TREE_TYPE (op0))
3975 /* Otherwise, if we're converting between two aggregate types, we
3976 might be allowed to substitute the VIEW_CONVERT_EXPR target type
3977 in place or to just convert the inner expression. */
3978 if (AGGREGATE_TYPE_P (type) && AGGREGATE_TYPE_P (etype))
3980 /* If we are converting between mere variants, we can just
3981 substitute the VIEW_CONVERT_EXPR in place. */
3982 if (gnat_types_compatible_p (type, etype))
3983 return build1 (VIEW_CONVERT_EXPR, type, op0);
3985 /* Otherwise, we may just bypass the input view conversion unless
3986 one of the types is a fat pointer, which is handled by
3987 specialized code below which relies on exact type matching. */
3988 else if (!TYPE_FAT_POINTER_P (type) && !TYPE_FAT_POINTER_P (etype))
3989 return convert (type, op0);
3995 /* If both types are record types, just convert the pointer and
3996 make a new INDIRECT_REF.
3998 ??? Disable this for now since it causes problems with the
3999 code in build_binary_op for MODIFY_EXPR which wants to
4000 strip off conversions. But that code really is a mess and
4001 we need to do this a much better way some time. */
4003 && (TREE_CODE (type) == RECORD_TYPE
4004 || TREE_CODE (type) == UNION_TYPE)
4005 && (TREE_CODE (etype) == RECORD_TYPE
4006 || TREE_CODE (etype) == UNION_TYPE)
4007 && !TYPE_FAT_POINTER_P (type) && !TYPE_FAT_POINTER_P (etype))
4008 return build_unary_op (INDIRECT_REF, NULL_TREE,
4009 convert (build_pointer_type (type),
4010 TREE_OPERAND (expr, 0)));
4017 /* Check for converting to a pointer to an unconstrained array. */
4018 if (TYPE_FAT_POINTER_P (type) && !TYPE_FAT_POINTER_P (etype))
4019 return convert_to_fat_pointer (type, expr);
4021 /* If we are converting between two aggregate types that are mere
4022 variants, just make a VIEW_CONVERT_EXPR. */
4023 else if (code == ecode
4024 && AGGREGATE_TYPE_P (type)
4025 && gnat_types_compatible_p (type, etype))
4026 return build1 (VIEW_CONVERT_EXPR, type, expr);
4028 /* In all other cases of related types, make a NOP_EXPR. */
4029 else if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (etype)
4030 || (code == INTEGER_CST && ecode == INTEGER_CST
4031 && (type == TREE_TYPE (etype) || etype == TREE_TYPE (type))))
4032 return fold_convert (type, expr);
4037 return fold_build1 (CONVERT_EXPR, type, expr);
4040 if (TYPE_HAS_ACTUAL_BOUNDS_P (type)
4041 && (ecode == ARRAY_TYPE || ecode == UNCONSTRAINED_ARRAY_TYPE
4042 || (ecode == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (etype))))
4043 return unchecked_convert (type, expr, false);
4044 else if (TYPE_BIASED_REPRESENTATION_P (type))
4045 return fold_convert (type,
4046 fold_build2 (MINUS_EXPR, TREE_TYPE (type),
4047 convert (TREE_TYPE (type), expr),
4048 TYPE_MIN_VALUE (type)));
4050 /* ... fall through ... */
4054 /* If we are converting an additive expression to an integer type
4055 with lower precision, be wary of the optimization that can be
4056 applied by convert_to_integer. There are 2 problematic cases:
4057 - if the first operand was originally of a biased type,
4058 because we could be recursively called to convert it
4059 to an intermediate type and thus rematerialize the
4060 additive operator endlessly,
4061 - if the expression contains a placeholder, because an
4062 intermediate conversion that changes the sign could
4063 be inserted and thus introduce an artificial overflow
4064 at compile time when the placeholder is substituted. */
4065 if (code == INTEGER_TYPE
4066 && ecode == INTEGER_TYPE
4067 && TYPE_PRECISION (type) < TYPE_PRECISION (etype)
4068 && (TREE_CODE (expr) == PLUS_EXPR || TREE_CODE (expr) == MINUS_EXPR))
4070 tree op0 = get_unwidened (TREE_OPERAND (expr, 0), type);
4072 if ((TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
4073 && TYPE_BIASED_REPRESENTATION_P (TREE_TYPE (op0)))
4074 || CONTAINS_PLACEHOLDER_P (expr))
4075 return build1 (NOP_EXPR, type, expr);
4078 return fold (convert_to_integer (type, expr));
4081 case REFERENCE_TYPE:
4082 /* If converting between two pointers to records denoting
4083 both a template and type, adjust if needed to account
4084 for any differing offsets, since one might be negative. */
4085 if (TYPE_THIN_POINTER_P (etype) && TYPE_THIN_POINTER_P (type))
4088 = size_diffop (bit_position (TYPE_FIELDS (TREE_TYPE (etype))),
4089 bit_position (TYPE_FIELDS (TREE_TYPE (type))));
4090 tree byte_diff = size_binop (CEIL_DIV_EXPR, bit_diff,
4091 sbitsize_int (BITS_PER_UNIT));
4093 expr = build1 (NOP_EXPR, type, expr);
4094 TREE_CONSTANT (expr) = TREE_CONSTANT (TREE_OPERAND (expr, 0));
4095 if (integer_zerop (byte_diff))
4098 return build_binary_op (POINTER_PLUS_EXPR, type, expr,
4099 fold (convert (sizetype, byte_diff)));
4102 /* If converting to a thin pointer, handle specially. */
4103 if (TYPE_THIN_POINTER_P (type)
4104 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)))
4105 return convert_to_thin_pointer (type, expr);
4107 /* If converting fat pointer to normal pointer, get the pointer to the
4108 array and then convert it. */
4109 else if (TYPE_FAT_POINTER_P (etype))
4110 expr = build_component_ref (expr, get_identifier ("P_ARRAY"),
4113 return fold (convert_to_pointer (type, expr));
4116 return fold (convert_to_real (type, expr));
4119 if (TYPE_JUSTIFIED_MODULAR_P (type) && !AGGREGATE_TYPE_P (etype))
4121 gnat_build_constructor
4122 (type, tree_cons (TYPE_FIELDS (type),
4123 convert (TREE_TYPE (TYPE_FIELDS (type)), expr),
4126 /* ... fall through ... */
4129 /* In these cases, assume the front-end has validated the conversion.
4130 If the conversion is valid, it will be a bit-wise conversion, so
4131 it can be viewed as an unchecked conversion. */
4132 return unchecked_convert (type, expr, false);
4135 /* This is a either a conversion between a tagged type and some
4136 subtype, which we have to mark as a UNION_TYPE because of
4137 overlapping fields or a conversion of an Unchecked_Union. */
4138 return unchecked_convert (type, expr, false);
4140 case UNCONSTRAINED_ARRAY_TYPE:
4141 /* If EXPR is a constrained array, take its address, convert it to a
4142 fat pointer, and then dereference it. Likewise if EXPR is a
4143 record containing both a template and a constrained array.
4144 Note that a record representing a justified modular type
4145 always represents a packed constrained array. */
4146 if (ecode == ARRAY_TYPE
4147 || (ecode == INTEGER_TYPE && TYPE_HAS_ACTUAL_BOUNDS_P (etype))
4148 || (ecode == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (etype))
4149 || (ecode == RECORD_TYPE && TYPE_JUSTIFIED_MODULAR_P (etype)))
4152 (INDIRECT_REF, NULL_TREE,
4153 convert_to_fat_pointer (TREE_TYPE (type),
4154 build_unary_op (ADDR_EXPR,
4157 /* Do something very similar for converting one unconstrained
4158 array to another. */
4159 else if (ecode == UNCONSTRAINED_ARRAY_TYPE)
4161 build_unary_op (INDIRECT_REF, NULL_TREE,
4162 convert (TREE_TYPE (type),
4163 build_unary_op (ADDR_EXPR,
4169 return fold (convert_to_complex (type, expr));
4176 /* Remove all conversions that are done in EXP. This includes converting
4177 from a padded type or to a justified modular type. If TRUE_ADDRESS
4178 is true, always return the address of the containing object even if
4179 the address is not bit-aligned. */
4182 remove_conversions (tree exp, bool true_address)
4184 switch (TREE_CODE (exp))
4188 && TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
4189 && TYPE_JUSTIFIED_MODULAR_P (TREE_TYPE (exp)))
4191 remove_conversions (VEC_index (constructor_elt,
4192 CONSTRUCTOR_ELTS (exp), 0)->value,
4197 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == RECORD_TYPE
4198 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
4199 return remove_conversions (TREE_OPERAND (exp, 0), true_address);
4202 case VIEW_CONVERT_EXPR: case NON_LVALUE_EXPR:
4204 return remove_conversions (TREE_OPERAND (exp, 0), true_address);
4213 /* If EXP's type is an UNCONSTRAINED_ARRAY_TYPE, return an expression that
4214 refers to the underlying array. If its type has TYPE_CONTAINS_TEMPLATE_P,
4215 likewise return an expression pointing to the underlying array. */
4218 maybe_unconstrained_array (tree exp)
4220 enum tree_code code = TREE_CODE (exp);
4223 switch (TREE_CODE (TREE_TYPE (exp)))
4225 case UNCONSTRAINED_ARRAY_TYPE:
4226 if (code == UNCONSTRAINED_ARRAY_REF)
4229 = build_unary_op (INDIRECT_REF, NULL_TREE,
4230 build_component_ref (TREE_OPERAND (exp, 0),
4231 get_identifier ("P_ARRAY"),
4233 TREE_READONLY (new) = TREE_STATIC (new) = TREE_READONLY (exp);
4237 else if (code == NULL_EXPR)
4238 return build1 (NULL_EXPR,
4239 TREE_TYPE (TREE_TYPE (TYPE_FIELDS
4240 (TREE_TYPE (TREE_TYPE (exp))))),
4241 TREE_OPERAND (exp, 0));
4244 /* If this is a padded type, convert to the unpadded type and see if
4245 it contains a template. */
4246 if (TYPE_IS_PADDING_P (TREE_TYPE (exp)))
4248 new = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (exp))), exp);
4249 if (TREE_CODE (TREE_TYPE (new)) == RECORD_TYPE
4250 && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (new)))
4252 build_component_ref (new, NULL_TREE,
4253 TREE_CHAIN (TYPE_FIELDS (TREE_TYPE (new))),
4256 else if (TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (exp)))
4258 build_component_ref (exp, NULL_TREE,
4259 TREE_CHAIN (TYPE_FIELDS (TREE_TYPE (exp))), 0);
4269 /* Return true if EXPR is an expression that can be folded as an operand
4270 of a VIEW_CONVERT_EXPR. See the head comment of unchecked_convert for
4274 can_fold_for_view_convert_p (tree expr)
4278 /* The folder will fold NOP_EXPRs between integral types with the same
4279 precision (in the middle-end's sense). We cannot allow it if the
4280 types don't have the same precision in the Ada sense as well. */
4281 if (TREE_CODE (expr) != NOP_EXPR)
4284 t1 = TREE_TYPE (expr);
4285 t2 = TREE_TYPE (TREE_OPERAND (expr, 0));
4287 /* Defer to the folder for non-integral conversions. */
4288 if (!(INTEGRAL_TYPE_P (t1) && INTEGRAL_TYPE_P (t2)))
4291 /* Only fold conversions that preserve both precisions. */
4292 if (TYPE_PRECISION (t1) == TYPE_PRECISION (t2)
4293 && operand_equal_p (rm_size (t1), rm_size (t2), 0))
4299 /* Return an expression that does an unchecked conversion of EXPR to TYPE.
4300 If NOTRUNC_P is true, truncation operations should be suppressed.
4302 Special care is required with (source or target) integral types whose
4303 precision is not equal to their size, to make sure we fetch or assign
4304 the value bits whose location might depend on the endianness, e.g.
4306 Rmsize : constant := 8;
4307 subtype Int is Integer range 0 .. 2 ** Rmsize - 1;
4309 type Bit_Array is array (1 .. Rmsize) of Boolean;
4310 pragma Pack (Bit_Array);
4312 function To_Bit_Array is new Unchecked_Conversion (Int, Bit_Array);
4314 Value : Int := 2#1000_0001#;
4315 Vbits : Bit_Array := To_Bit_Array (Value);
4317 we expect the 8 bits at Vbits'Address to always contain Value, while
4318 their original location depends on the endianness, at Value'Address
4319 on a little-endian architecture but not on a big-endian one.
4321 ??? There is a problematic discrepancy between what is called precision
4322 here (and more generally throughout gigi) for integral types and what is
4323 called precision in the middle-end. In the former case it's the RM size
4324 as given by TYPE_RM_SIZE (or rm_size) whereas it's TYPE_PRECISION in the
4325 latter case, the hitch being that they are not equal when they matter,
4326 that is when the number of value bits is not equal to the type's size:
4327 TYPE_RM_SIZE does give the number of value bits but TYPE_PRECISION is set
4328 to the size. The sole exception are BOOLEAN_TYPEs for which both are 1.
4330 The consequence is that gigi must duplicate code bridging the gap between
4331 the type's size and its precision that exists for TYPE_PRECISION in the
4332 middle-end, because the latter knows nothing about TYPE_RM_SIZE, and be
4333 wary of transformations applied in the middle-end based on TYPE_PRECISION
4334 because this value doesn't reflect the actual precision for Ada. */
4337 unchecked_convert (tree type, tree expr, bool notrunc_p)
4339 tree etype = TREE_TYPE (expr);
4341 /* If the expression is already the right type, we are done. */
4345 /* If both types types are integral just do a normal conversion.
4346 Likewise for a conversion to an unconstrained array. */
4347 if ((((INTEGRAL_TYPE_P (type)
4348 && !(TREE_CODE (type) == INTEGER_TYPE
4349 && TYPE_VAX_FLOATING_POINT_P (type)))
4350 || (POINTER_TYPE_P (type) && ! TYPE_THIN_POINTER_P (type))
4351 || (TREE_CODE (type) == RECORD_TYPE
4352 && TYPE_JUSTIFIED_MODULAR_P (type)))
4353 && ((INTEGRAL_TYPE_P (etype)
4354 && !(TREE_CODE (etype) == INTEGER_TYPE
4355 && TYPE_VAX_FLOATING_POINT_P (etype)))
4356 || (POINTER_TYPE_P (etype) && !TYPE_THIN_POINTER_P (etype))
4357 || (TREE_CODE (etype) == RECORD_TYPE
4358 && TYPE_JUSTIFIED_MODULAR_P (etype))))
4359 || TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
4361 if (TREE_CODE (etype) == INTEGER_TYPE
4362 && TYPE_BIASED_REPRESENTATION_P (etype))
4364 tree ntype = copy_type (etype);
4365 TYPE_BIASED_REPRESENTATION_P (ntype) = 0;
4366 TYPE_MAIN_VARIANT (ntype) = ntype;
4367 expr = build1 (NOP_EXPR, ntype, expr);
4370 if (TREE_CODE (type) == INTEGER_TYPE
4371 && TYPE_BIASED_REPRESENTATION_P (type))
4373 tree rtype = copy_type (type);
4374 TYPE_BIASED_REPRESENTATION_P (rtype) = 0;
4375 TYPE_MAIN_VARIANT (rtype) = rtype;
4376 expr = convert (rtype, expr);
4377 expr = build1 (NOP_EXPR, type, expr);
4380 /* We have another special case: if we are unchecked converting either
4381 a subtype or a type with limited range into a base type, we need to
4382 ensure that VRP doesn't propagate range information because this
4383 conversion may be done precisely to validate that the object is
4384 within the range it is supposed to have. */
4385 else if (TREE_CODE (expr) != INTEGER_CST
4386 && TREE_CODE (type) == INTEGER_TYPE && !TREE_TYPE (type)
4387 && ((TREE_CODE (etype) == INTEGER_TYPE && TREE_TYPE (etype))
4388 || TREE_CODE (etype) == ENUMERAL_TYPE
4389 || TREE_CODE (etype) == BOOLEAN_TYPE))
4391 /* The optimization barrier is a VIEW_CONVERT_EXPR node; moreover,
4392 in order not to be deemed an useless type conversion, it must
4393 be from subtype to base type.
4395 Therefore we first do the bulk of the conversion to a subtype of
4396 the final type. And this conversion must itself not be deemed
4397 useless if the source type is not a subtype because, otherwise,
4398 the final VIEW_CONVERT_EXPR will be deemed so as well. That's
4399 why we toggle the unsigned flag in this conversion, which is
4400 harmless since the final conversion is only a reinterpretation
4403 ??? This may raise addressability and/or aliasing issues because
4404 VIEW_CONVERT_EXPR gets gimplified as an lvalue, thus causing the
4405 address of its operand to be taken if it is deemed addressable
4406 and not already in GIMPLE form. */
4408 = gnat_type_for_mode (TYPE_MODE (type), !TYPE_UNSIGNED (etype));
4409 rtype = copy_type (rtype);
4410 TYPE_MAIN_VARIANT (rtype) = rtype;
4411 TREE_TYPE (rtype) = type;
4412 expr = convert (rtype, expr);
4413 expr = build1 (VIEW_CONVERT_EXPR, type, expr);
4417 expr = convert (type, expr);
4420 /* If we are converting to an integral type whose precision is not equal
4421 to its size, first unchecked convert to a record that contains an
4422 object of the output type. Then extract the field. */
4423 else if (INTEGRAL_TYPE_P (type) && TYPE_RM_SIZE (type)
4424 && 0 != compare_tree_int (TYPE_RM_SIZE (type),
4425 GET_MODE_BITSIZE (TYPE_MODE (type))))
4427 tree rec_type = make_node (RECORD_TYPE);
4428 tree field = create_field_decl (get_identifier ("OBJ"), type,
4429 rec_type, 1, 0, 0, 0);
4431 TYPE_FIELDS (rec_type) = field;
4432 layout_type (rec_type);
4434 expr = unchecked_convert (rec_type, expr, notrunc_p);
4435 expr = build_component_ref (expr, NULL_TREE, field, 0);
4438 /* Similarly if we are converting from an integral type whose precision
4439 is not equal to its size. */
4440 else if (INTEGRAL_TYPE_P (etype) && TYPE_RM_SIZE (etype)
4441 && 0 != compare_tree_int (TYPE_RM_SIZE (etype),
4442 GET_MODE_BITSIZE (TYPE_MODE (etype))))
4444 tree rec_type = make_node (RECORD_TYPE);
4446 = create_field_decl (get_identifier ("OBJ"), etype, rec_type,
4449 TYPE_FIELDS (rec_type) = field;
4450 layout_type (rec_type);
4452 expr = gnat_build_constructor (rec_type, build_tree_list (field, expr));
4453 expr = unchecked_convert (type, expr, notrunc_p);
4456 /* We have a special case when we are converting between two
4457 unconstrained array types. In that case, take the address,
4458 convert the fat pointer types, and dereference. */
4459 else if (TREE_CODE (etype) == UNCONSTRAINED_ARRAY_TYPE
4460 && TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
4461 expr = build_unary_op (INDIRECT_REF, NULL_TREE,
4462 build1 (VIEW_CONVERT_EXPR, TREE_TYPE (type),
4463 build_unary_op (ADDR_EXPR, NULL_TREE,
4467 expr = maybe_unconstrained_array (expr);
4468 etype = TREE_TYPE (expr);
4469 if (can_fold_for_view_convert_p (expr))
4470 expr = fold_build1 (VIEW_CONVERT_EXPR, type, expr);
4472 expr = build1 (VIEW_CONVERT_EXPR, type, expr);
4475 /* If the result is an integral type whose precision is not equal to its
4476 size, sign- or zero-extend the result. We need not do this if the input
4477 is an integral type of the same precision and signedness or if the output
4478 is a biased type or if both the input and output are unsigned. */
4480 && INTEGRAL_TYPE_P (type) && TYPE_RM_SIZE (type)
4481 && !(TREE_CODE (type) == INTEGER_TYPE
4482 && TYPE_BIASED_REPRESENTATION_P (type))
4483 && 0 != compare_tree_int (TYPE_RM_SIZE (type),
4484 GET_MODE_BITSIZE (TYPE_MODE (type)))
4485 && !(INTEGRAL_TYPE_P (etype)
4486 && TYPE_UNSIGNED (type) == TYPE_UNSIGNED (etype)
4487 && operand_equal_p (TYPE_RM_SIZE (type),
4488 (TYPE_RM_SIZE (etype) != 0
4489 ? TYPE_RM_SIZE (etype) : TYPE_SIZE (etype)),
4491 && !(TYPE_UNSIGNED (type) && TYPE_UNSIGNED (etype)))
4493 tree base_type = gnat_type_for_mode (TYPE_MODE (type),
4494 TYPE_UNSIGNED (type));
4496 = convert (base_type,
4497 size_binop (MINUS_EXPR,
4499 (GET_MODE_BITSIZE (TYPE_MODE (type))),
4500 TYPE_RM_SIZE (type)));
4503 build_binary_op (RSHIFT_EXPR, base_type,
4504 build_binary_op (LSHIFT_EXPR, base_type,
4505 convert (base_type, expr),
4510 /* An unchecked conversion should never raise Constraint_Error. The code
4511 below assumes that GCC's conversion routines overflow the same way that
4512 the underlying hardware does. This is probably true. In the rare case
4513 when it is false, we can rely on the fact that such conversions are
4514 erroneous anyway. */
4515 if (TREE_CODE (expr) == INTEGER_CST)
4516 TREE_OVERFLOW (expr) = 0;
4518 /* If the sizes of the types differ and this is an VIEW_CONVERT_EXPR,
4519 show no longer constant. */
4520 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
4521 && !operand_equal_p (TYPE_SIZE_UNIT (type), TYPE_SIZE_UNIT (etype),
4523 TREE_CONSTANT (expr) = 0;
4528 /* Return the appropriate GCC tree code for the specified GNAT type,
4529 the latter being a record type as predicated by Is_Record_Type. */
4532 tree_code_for_record_type (Entity_Id gnat_type)
4534 Node_Id component_list
4535 = Component_List (Type_Definition
4537 (Implementation_Base_Type (gnat_type))));
4540 /* Make this a UNION_TYPE unless it's either not an Unchecked_Union or
4541 we have a non-discriminant field outside a variant. In either case,
4542 it's a RECORD_TYPE. */
4544 if (!Is_Unchecked_Union (gnat_type))
4547 for (component = First_Non_Pragma (Component_Items (component_list));
4548 Present (component);
4549 component = Next_Non_Pragma (component))
4550 if (Ekind (Defining_Entity (component)) == E_Component)
4556 /* Return true if GNU_TYPE is suitable as the type of a non-aliased
4557 component of an aggregate type. */
4560 type_for_nonaliased_component_p (tree gnu_type)
4562 /* If the type is passed by reference, we may have pointers to the
4563 component so it cannot be made non-aliased. */
4564 if (must_pass_by_ref (gnu_type) || default_pass_by_ref (gnu_type))
4567 /* We used to say that any component of aggregate type is aliased
4568 because the front-end may take 'Reference of it. The front-end
4569 has been enhanced in the meantime so as to use a renaming instead
4570 in most cases, but the back-end can probably take the address of
4571 such a component too so we go for the conservative stance.
4573 For instance, we might need the address of any array type, even
4574 if normally passed by copy, to construct a fat pointer if the
4575 component is used as an actual for an unconstrained formal.
4577 Likewise for record types: even if a specific record subtype is
4578 passed by copy, the parent type might be passed by ref (e.g. if
4579 it's of variable size) and we might take the address of a child
4580 component to pass to a parent formal. We have no way to check
4581 for such conditions here. */
4582 if (AGGREGATE_TYPE_P (gnu_type))
4588 /* Perform final processing on global variables. */
4591 gnat_write_global_declarations (void)
4593 /* Proceed to optimize and emit assembly.
4594 FIXME: shouldn't be the front end's responsibility to call this. */
4597 /* Emit debug info for all global declarations. */
4598 emit_debug_global_declarations (VEC_address (tree, global_decls),
4599 VEC_length (tree, global_decls));
4602 /* ************************************************************************
4603 * * GCC builtins support *
4604 * ************************************************************************ */
4606 /* The general scheme is fairly simple:
4608 For each builtin function/type to be declared, gnat_install_builtins calls
4609 internal facilities which eventually get to gnat_push_decl, which in turn
4610 tracks the so declared builtin function decls in the 'builtin_decls' global
4611 datastructure. When an Intrinsic subprogram declaration is processed, we
4612 search this global datastructure to retrieve the associated BUILT_IN DECL
4615 /* Search the chain of currently available builtin declarations for a node
4616 corresponding to function NAME (an IDENTIFIER_NODE). Return the first node
4617 found, if any, or NULL_TREE otherwise. */
4619 builtin_decl_for (tree name)
4624 for (i = 0; VEC_iterate(tree, builtin_decls, i, decl); i++)
4625 if (DECL_NAME (decl) == name)
4631 /* The code below eventually exposes gnat_install_builtins, which declares
4632 the builtin types and functions we might need, either internally or as
4633 user accessible facilities.
4635 ??? This is a first implementation shot, still in rough shape. It is
4636 heavily inspired from the "C" family implementation, with chunks copied
4637 verbatim from there.
4639 Two obvious TODO candidates are
4640 o Use a more efficient name/decl mapping scheme
4641 o Devise a middle-end infrastructure to avoid having to copy
4642 pieces between front-ends. */
4644 /* ----------------------------------------------------------------------- *
4645 * BUILTIN ELEMENTARY TYPES *
4646 * ----------------------------------------------------------------------- */
4648 /* Standard data types to be used in builtin argument declarations. */
4652 CTI_SIGNED_SIZE_TYPE, /* For format checking only. */
4654 CTI_CONST_STRING_TYPE,
4659 static tree c_global_trees[CTI_MAX];
4661 #define signed_size_type_node c_global_trees[CTI_SIGNED_SIZE_TYPE]
4662 #define string_type_node c_global_trees[CTI_STRING_TYPE]
4663 #define const_string_type_node c_global_trees[CTI_CONST_STRING_TYPE]
4665 /* ??? In addition some attribute handlers, we currently don't support a
4666 (small) number of builtin-types, which in turns inhibits support for a
4667 number of builtin functions. */
4668 #define wint_type_node void_type_node
4669 #define intmax_type_node void_type_node
4670 #define uintmax_type_node void_type_node
4672 /* Build the void_list_node (void_type_node having been created). */
4675 build_void_list_node (void)
4677 tree t = build_tree_list (NULL_TREE, void_type_node);
4681 /* Used to help initialize the builtin-types.def table. When a type of
4682 the correct size doesn't exist, use error_mark_node instead of NULL.
4683 The later results in segfaults even when a decl using the type doesn't
4687 builtin_type_for_size (int size, bool unsignedp)
4689 tree type = lang_hooks.types.type_for_size (size, unsignedp);
4690 return type ? type : error_mark_node;
4693 /* Build/push the elementary type decls that builtin functions/types
4697 install_builtin_elementary_types (void)
4699 signed_size_type_node = size_type_node;
4700 pid_type_node = integer_type_node;
4701 void_list_node = build_void_list_node ();
4703 string_type_node = build_pointer_type (char_type_node);
4704 const_string_type_node
4705 = build_pointer_type (build_qualified_type
4706 (char_type_node, TYPE_QUAL_CONST));
4709 /* ----------------------------------------------------------------------- *
4710 * BUILTIN FUNCTION TYPES *
4711 * ----------------------------------------------------------------------- */
4713 /* Now, builtin function types per se. */
4717 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
4718 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
4719 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
4720 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
4721 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4722 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4723 #define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
4724 #define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME,
4725 #define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME,
4726 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
4727 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
4728 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
4729 #define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
4730 #define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
4731 #define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \
4733 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
4734 #include "builtin-types.def"
4735 #undef DEF_PRIMITIVE_TYPE
4736 #undef DEF_FUNCTION_TYPE_0
4737 #undef DEF_FUNCTION_TYPE_1
4738 #undef DEF_FUNCTION_TYPE_2
4739 #undef DEF_FUNCTION_TYPE_3
4740 #undef DEF_FUNCTION_TYPE_4
4741 #undef DEF_FUNCTION_TYPE_5
4742 #undef DEF_FUNCTION_TYPE_6
4743 #undef DEF_FUNCTION_TYPE_7
4744 #undef DEF_FUNCTION_TYPE_VAR_0
4745 #undef DEF_FUNCTION_TYPE_VAR_1
4746 #undef DEF_FUNCTION_TYPE_VAR_2
4747 #undef DEF_FUNCTION_TYPE_VAR_3
4748 #undef DEF_FUNCTION_TYPE_VAR_4
4749 #undef DEF_FUNCTION_TYPE_VAR_5
4750 #undef DEF_POINTER_TYPE
4754 typedef enum c_builtin_type builtin_type;
4756 /* A temporary array used in communication with def_fn_type. */
4757 static GTY(()) tree builtin_types[(int) BT_LAST + 1];
4759 /* A helper function for install_builtin_types. Build function type
4760 for DEF with return type RET and N arguments. If VAR is true, then the
4761 function should be variadic after those N arguments.
4763 Takes special care not to ICE if any of the types involved are
4764 error_mark_node, which indicates that said type is not in fact available
4765 (see builtin_type_for_size). In which case the function type as a whole
4766 should be error_mark_node. */
4769 def_fn_type (builtin_type def, builtin_type ret, bool var, int n, ...)
4771 tree args = NULL, t;
4776 for (i = 0; i < n; ++i)
4778 builtin_type a = va_arg (list, builtin_type);
4779 t = builtin_types[a];
4780 if (t == error_mark_node)
4782 args = tree_cons (NULL_TREE, t, args);
4786 args = nreverse (args);
4788 args = chainon (args, void_list_node);
4790 t = builtin_types[ret];
4791 if (t == error_mark_node)
4793 t = build_function_type (t, args);
4796 builtin_types[def] = t;
4799 /* Build the builtin function types and install them in the builtin_types
4800 array for later use in builtin function decls. */
4803 install_builtin_function_types (void)
4805 tree va_list_ref_type_node;
4806 tree va_list_arg_type_node;
4808 if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
4810 va_list_arg_type_node = va_list_ref_type_node =
4811 build_pointer_type (TREE_TYPE (va_list_type_node));
4815 va_list_arg_type_node = va_list_type_node;
4816 va_list_ref_type_node = build_reference_type (va_list_type_node);
4819 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
4820 builtin_types[ENUM] = VALUE;
4821 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
4822 def_fn_type (ENUM, RETURN, 0, 0);
4823 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
4824 def_fn_type (ENUM, RETURN, 0, 1, ARG1);
4825 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
4826 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
4827 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4828 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
4829 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4830 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
4831 #define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4832 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4833 #define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4835 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
4836 #define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
4838 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
4839 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
4840 def_fn_type (ENUM, RETURN, 1, 0);
4841 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
4842 def_fn_type (ENUM, RETURN, 1, 1, ARG1);
4843 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
4844 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
4845 #define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
4846 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
4847 #define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
4848 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
4849 #define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
4850 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
4851 #define DEF_POINTER_TYPE(ENUM, TYPE) \
4852 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
4854 #include "builtin-types.def"
4856 #undef DEF_PRIMITIVE_TYPE
4857 #undef DEF_FUNCTION_TYPE_1
4858 #undef DEF_FUNCTION_TYPE_2
4859 #undef DEF_FUNCTION_TYPE_3
4860 #undef DEF_FUNCTION_TYPE_4
4861 #undef DEF_FUNCTION_TYPE_5
4862 #undef DEF_FUNCTION_TYPE_6
4863 #undef DEF_FUNCTION_TYPE_VAR_0
4864 #undef DEF_FUNCTION_TYPE_VAR_1
4865 #undef DEF_FUNCTION_TYPE_VAR_2
4866 #undef DEF_FUNCTION_TYPE_VAR_3
4867 #undef DEF_FUNCTION_TYPE_VAR_4
4868 #undef DEF_FUNCTION_TYPE_VAR_5
4869 #undef DEF_POINTER_TYPE
4870 builtin_types[(int) BT_LAST] = NULL_TREE;
4873 /* ----------------------------------------------------------------------- *
4874 * BUILTIN ATTRIBUTES *
4875 * ----------------------------------------------------------------------- */
4877 enum built_in_attribute
4879 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
4880 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
4881 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
4882 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
4883 #include "builtin-attrs.def"
4884 #undef DEF_ATTR_NULL_TREE
4886 #undef DEF_ATTR_IDENT
4887 #undef DEF_ATTR_TREE_LIST
4891 static GTY(()) tree built_in_attributes[(int) ATTR_LAST];
4894 install_builtin_attributes (void)
4896 /* Fill in the built_in_attributes array. */
4897 #define DEF_ATTR_NULL_TREE(ENUM) \
4898 built_in_attributes[(int) ENUM] = NULL_TREE;
4899 #define DEF_ATTR_INT(ENUM, VALUE) \
4900 built_in_attributes[(int) ENUM] = build_int_cst (NULL_TREE, VALUE);
4901 #define DEF_ATTR_IDENT(ENUM, STRING) \
4902 built_in_attributes[(int) ENUM] = get_identifier (STRING);
4903 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
4904 built_in_attributes[(int) ENUM] \
4905 = tree_cons (built_in_attributes[(int) PURPOSE], \
4906 built_in_attributes[(int) VALUE], \
4907 built_in_attributes[(int) CHAIN]);
4908 #include "builtin-attrs.def"
4909 #undef DEF_ATTR_NULL_TREE
4911 #undef DEF_ATTR_IDENT
4912 #undef DEF_ATTR_TREE_LIST
4915 /* Handle a "const" attribute; arguments as in
4916 struct attribute_spec.handler. */
4919 handle_const_attribute (tree *node, tree ARG_UNUSED (name),
4920 tree ARG_UNUSED (args), int ARG_UNUSED (flags),
4923 if (TREE_CODE (*node) == FUNCTION_DECL)
4924 TREE_READONLY (*node) = 1;
4926 *no_add_attrs = true;
4931 /* Handle a "nothrow" attribute; arguments as in
4932 struct attribute_spec.handler. */
4935 handle_nothrow_attribute (tree *node, tree ARG_UNUSED (name),
4936 tree ARG_UNUSED (args), int ARG_UNUSED (flags),
4939 if (TREE_CODE (*node) == FUNCTION_DECL)
4940 TREE_NOTHROW (*node) = 1;
4942 *no_add_attrs = true;
4947 /* Handle a "pure" attribute; arguments as in
4948 struct attribute_spec.handler. */
4951 handle_pure_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4952 int ARG_UNUSED (flags), bool *no_add_attrs)
4954 if (TREE_CODE (*node) == FUNCTION_DECL)
4955 DECL_PURE_P (*node) = 1;
4956 /* ??? TODO: Support types. */
4959 warning (OPT_Wattributes, "%qE attribute ignored", name);
4960 *no_add_attrs = true;
4966 /* Handle a "no vops" attribute; arguments as in
4967 struct attribute_spec.handler. */
4970 handle_novops_attribute (tree *node, tree ARG_UNUSED (name),
4971 tree ARG_UNUSED (args), int ARG_UNUSED (flags),
4972 bool *ARG_UNUSED (no_add_attrs))
4974 gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
4975 DECL_IS_NOVOPS (*node) = 1;
4979 /* Helper for nonnull attribute handling; fetch the operand number
4980 from the attribute argument list. */
4983 get_nonnull_operand (tree arg_num_expr, unsigned HOST_WIDE_INT *valp)
4985 /* Verify the arg number is a constant. */
4986 if (TREE_CODE (arg_num_expr) != INTEGER_CST
4987 || TREE_INT_CST_HIGH (arg_num_expr) != 0)
4990 *valp = TREE_INT_CST_LOW (arg_num_expr);
4994 /* Handle the "nonnull" attribute. */
4996 handle_nonnull_attribute (tree *node, tree ARG_UNUSED (name),
4997 tree args, int ARG_UNUSED (flags),
5001 unsigned HOST_WIDE_INT attr_arg_num;
5003 /* If no arguments are specified, all pointer arguments should be
5004 non-null. Verify a full prototype is given so that the arguments
5005 will have the correct types when we actually check them later. */
5008 if (!TYPE_ARG_TYPES (type))
5010 error ("nonnull attribute without arguments on a non-prototype");
5011 *no_add_attrs = true;
5016 /* Argument list specified. Verify that each argument number references
5017 a pointer argument. */
5018 for (attr_arg_num = 1; args; args = TREE_CHAIN (args))
5021 unsigned HOST_WIDE_INT arg_num = 0, ck_num;
5023 if (!get_nonnull_operand (TREE_VALUE (args), &arg_num))
5025 error ("nonnull argument has invalid operand number (argument %lu)",
5026 (unsigned long) attr_arg_num);
5027 *no_add_attrs = true;
5031 argument = TYPE_ARG_TYPES (type);
5034 for (ck_num = 1; ; ck_num++)
5036 if (!argument || ck_num == arg_num)
5038 argument = TREE_CHAIN (argument);
5042 || TREE_CODE (TREE_VALUE (argument)) == VOID_TYPE)
5044 error ("nonnull argument with out-of-range operand number (argument %lu, operand %lu)",
5045 (unsigned long) attr_arg_num, (unsigned long) arg_num);
5046 *no_add_attrs = true;
5050 if (TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE)
5052 error ("nonnull argument references non-pointer operand (argument %lu, operand %lu)",
5053 (unsigned long) attr_arg_num, (unsigned long) arg_num);
5054 *no_add_attrs = true;
5063 /* Handle a "sentinel" attribute. */
5066 handle_sentinel_attribute (tree *node, tree name, tree args,
5067 int ARG_UNUSED (flags), bool *no_add_attrs)
5069 tree params = TYPE_ARG_TYPES (*node);
5073 warning (OPT_Wattributes,
5074 "%qE attribute requires prototypes with named arguments", name);
5075 *no_add_attrs = true;
5079 while (TREE_CHAIN (params))
5080 params = TREE_CHAIN (params);
5082 if (VOID_TYPE_P (TREE_VALUE (params)))
5084 warning (OPT_Wattributes,
5085 "%qE attribute only applies to variadic functions", name);
5086 *no_add_attrs = true;
5092 tree position = TREE_VALUE (args);
5094 if (TREE_CODE (position) != INTEGER_CST)
5096 warning (0, "requested position is not an integer constant");
5097 *no_add_attrs = true;
5101 if (tree_int_cst_lt (position, integer_zero_node))
5103 warning (0, "requested position is less than zero");
5104 *no_add_attrs = true;
5112 /* Handle a "noreturn" attribute; arguments as in
5113 struct attribute_spec.handler. */
5116 handle_noreturn_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5117 int ARG_UNUSED (flags), bool *no_add_attrs)
5119 tree type = TREE_TYPE (*node);
5121 /* See FIXME comment in c_common_attribute_table. */
5122 if (TREE_CODE (*node) == FUNCTION_DECL)
5123 TREE_THIS_VOLATILE (*node) = 1;
5124 else if (TREE_CODE (type) == POINTER_TYPE
5125 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
5127 = build_pointer_type
5128 (build_type_variant (TREE_TYPE (type),
5129 TYPE_READONLY (TREE_TYPE (type)), 1));
5132 warning (OPT_Wattributes, "%qE attribute ignored", name);
5133 *no_add_attrs = true;
5139 /* Handle a "malloc" attribute; arguments as in
5140 struct attribute_spec.handler. */
5143 handle_malloc_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5144 int ARG_UNUSED (flags), bool *no_add_attrs)
5146 if (TREE_CODE (*node) == FUNCTION_DECL
5147 && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (*node))))
5148 DECL_IS_MALLOC (*node) = 1;
5151 warning (OPT_Wattributes, "%qE attribute ignored", name);
5152 *no_add_attrs = true;
5158 /* Fake handler for attributes we don't properly support. */
5161 fake_attribute_handler (tree * ARG_UNUSED (node),
5162 tree ARG_UNUSED (name),
5163 tree ARG_UNUSED (args),
5164 int ARG_UNUSED (flags),
5165 bool * ARG_UNUSED (no_add_attrs))
5170 /* Handle a "type_generic" attribute. */
5173 handle_type_generic_attribute (tree *node, tree ARG_UNUSED (name),
5174 tree ARG_UNUSED (args), int ARG_UNUSED (flags),
5175 bool * ARG_UNUSED (no_add_attrs))
5179 /* Ensure we have a function type. */
5180 gcc_assert (TREE_CODE (*node) == FUNCTION_TYPE);
5182 params = TYPE_ARG_TYPES (*node);
5183 while (params && ! VOID_TYPE_P (TREE_VALUE (params)))
5184 params = TREE_CHAIN (params);
5186 /* Ensure we have a variadic function. */
5187 gcc_assert (!params);
5192 /* ----------------------------------------------------------------------- *
5193 * BUILTIN FUNCTIONS *
5194 * ----------------------------------------------------------------------- */
5196 /* Worker for DEF_BUILTIN. Possibly define a builtin function with one or two
5197 names. Does not declare a non-__builtin_ function if flag_no_builtin, or
5198 if nonansi_p and flag_no_nonansi_builtin. */
5201 def_builtin_1 (enum built_in_function fncode,
5203 enum built_in_class fnclass,
5204 tree fntype, tree libtype,
5205 bool both_p, bool fallback_p,
5206 bool nonansi_p ATTRIBUTE_UNUSED,
5207 tree fnattrs, bool implicit_p)
5210 const char *libname;
5212 /* Preserve an already installed decl. It most likely was setup in advance
5213 (e.g. as part of the internal builtins) for specific reasons. */
5214 if (built_in_decls[(int) fncode] != NULL_TREE)
5217 gcc_assert ((!both_p && !fallback_p)
5218 || !strncmp (name, "__builtin_",
5219 strlen ("__builtin_")));
5221 libname = name + strlen ("__builtin_");
5222 decl = add_builtin_function (name, fntype, fncode, fnclass,
5223 (fallback_p ? libname : NULL),
5226 /* ??? This is normally further controlled by command-line options
5227 like -fno-builtin, but we don't have them for Ada. */
5228 add_builtin_function (libname, libtype, fncode, fnclass,
5231 built_in_decls[(int) fncode] = decl;
5233 implicit_built_in_decls[(int) fncode] = decl;
5236 static int flag_isoc94 = 0;
5237 static int flag_isoc99 = 0;
5239 /* Install what the common builtins.def offers. */
5242 install_builtin_functions (void)
5244 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
5245 NONANSI_P, ATTRS, IMPLICIT, COND) \
5247 def_builtin_1 (ENUM, NAME, CLASS, \
5248 builtin_types[(int) TYPE], \
5249 builtin_types[(int) LIBTYPE], \
5250 BOTH_P, FALLBACK_P, NONANSI_P, \
5251 built_in_attributes[(int) ATTRS], IMPLICIT);
5252 #include "builtins.def"
5256 /* ----------------------------------------------------------------------- *
5257 * BUILTIN FUNCTIONS *
5258 * ----------------------------------------------------------------------- */
5260 /* Install the builtin functions we might need. */
5263 gnat_install_builtins (void)
5265 install_builtin_elementary_types ();
5266 install_builtin_function_types ();
5267 install_builtin_attributes ();
5269 /* Install builtins used by generic middle-end pieces first. Some of these
5270 know about internal specificities and control attributes accordingly, for
5271 instance __builtin_alloca vs no-throw and -fstack-check. We will ignore
5272 the generic definition from builtins.def. */
5273 build_common_builtin_nodes ();
5275 /* Now, install the target specific builtins, such as the AltiVec family on
5276 ppc, and the common set as exposed by builtins.def. */
5277 targetm.init_builtins ();
5278 install_builtin_functions ();
5281 #include "gt-ada-utils.h"
5282 #include "gtype-ada.h"
OSDN Git Service
