1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
11 * Copyright (C) 1992-2001, Free Software Foundation, Inc. *
13 * GNAT is free software; you can redistribute it and/or modify it under *
14 * terms of the GNU General Public License as published by the Free Soft- *
15 * ware Foundation; either version 2, or (at your option) any later ver- *
16 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
17 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
18 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
19 * for more details. You should have received a copy of the GNU General *
20 * Public License distributed with GNAT; see file COPYING. If not, write *
21 * to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, *
22 * MA 02111-1307, USA. *
24 * GNAT was originally developed by the GNAT team at New York University. *
25 * It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). *
27 ****************************************************************************/
53 #ifndef MAX_FIXED_MODE_SIZE
54 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
57 #ifndef MAX_BITS_PER_WORD
58 #define MAX_BITS_PER_WORD BITS_PER_WORD
61 /* If nonzero, pretend we are allocating at global level. */
64 /* Global Variables for the various types we create. */
65 tree gnat_std_decls[(int) ADT_LAST];
67 /* Associates a GNAT tree node to a GCC tree node. It is used in
68 `save_gnu_tree', `get_gnu_tree' and `present_gnu_tree'. See documentation
69 of `save_gnu_tree' for more info. */
70 static tree *associate_gnat_to_gnu;
72 /* This listhead is used to record any global objects that need elaboration.
73 TREE_PURPOSE is the variable to be elaborated and TREE_VALUE is the
74 initial value to assign. */
76 static tree pending_elaborations;
78 /* This stack allows us to momentarily switch to generating elaboration
79 lists for an inner context. */
81 static struct e_stack {struct e_stack *next; tree elab_list; } *elist_stack;
83 /* This variable keeps a table for types for each precision so that we only
84 allocate each of them once. Signed and unsigned types are kept separate.
86 Note that these types are only used when fold-const requests something
87 special. Perhaps we should NOT share these types; we'll see how it
89 static tree signed_and_unsigned_types[2 * MAX_BITS_PER_WORD + 1][2];
91 /* Likewise for float types, but record these by mode. */
92 static tree float_types[NUM_MACHINE_MODES];
94 /* For each binding contour we allocate a binding_level structure which records
95 the entities defined or declared in that contour. Contours include:
98 one for each subprogram definition
99 one for each compound statement (declare block)
101 Binding contours are used to create GCC tree BLOCK nodes. */
105 /* A chain of ..._DECL nodes for all variables, constants, functions,
106 parameters and type declarations. These ..._DECL nodes are chained
107 through the TREE_CHAIN field. Note that these ..._DECL nodes are stored
108 in the reverse of the order supplied to be compatible with the
111 /* For each level (except the global one), a chain of BLOCK nodes for all
112 the levels that were entered and exited one level down from this one. */
114 /* The BLOCK node for this level, if one has been preallocated.
115 If 0, the BLOCK is allocated (if needed) when the level is popped. */
117 /* The binding level containing this one (the enclosing binding level). */
118 struct binding_level *level_chain;
121 /* The binding level currently in effect. */
122 static struct binding_level *current_binding_level = NULL;
124 /* A chain of binding_level structures awaiting reuse. */
125 static struct binding_level *free_binding_level = NULL;
127 /* The outermost binding level. This binding level is created when the
128 compiler is started and it will exist through the entire compilation. */
129 static struct binding_level *global_binding_level;
131 /* Binding level structures are initialized by copying this one. */
132 static struct binding_level clear_binding_level = {NULL, NULL, NULL, NULL};
135 static tree merge_sizes PARAMS ((tree, tree, tree, int, int));
136 static tree compute_related_constant PARAMS ((tree, tree));
137 static tree split_plus PARAMS ((tree, tree *));
138 static int value_zerop PARAMS ((tree));
139 static tree float_type_for_size PARAMS ((int, enum machine_mode));
140 static tree convert_to_fat_pointer PARAMS ((tree, tree));
141 static tree convert_to_thin_pointer PARAMS ((tree, tree));
142 static tree make_descriptor_field PARAMS ((const char *,tree, tree,
144 static void mark_binding_level PARAMS((PTR));
145 static void mark_e_stack PARAMS((PTR));
147 /* Initialize the association of GNAT nodes to GCC trees. */
154 associate_gnat_to_gnu = (tree *) xmalloc (max_gnat_nodes * sizeof (tree));
155 ggc_add_tree_root (associate_gnat_to_gnu, max_gnat_nodes);
157 for (gnat_node = 0; gnat_node < max_gnat_nodes; gnat_node++)
158 associate_gnat_to_gnu [gnat_node] = NULL_TREE;
160 associate_gnat_to_gnu -= First_Node_Id;
162 pending_elaborations = build_tree_list (NULL_TREE, NULL_TREE);
163 ggc_add_tree_root (&pending_elaborations, 1);
164 ggc_add_root ((PTR) &elist_stack, 1, sizeof (struct e_stack), mark_e_stack);
165 ggc_add_tree_root (&signed_and_unsigned_types[0][0],
166 (sizeof signed_and_unsigned_types
167 / sizeof signed_and_unsigned_types[0][0]));
168 ggc_add_tree_root (float_types, ARRAY_SIZE (float_types));
170 ggc_add_root (¤t_binding_level, 1, sizeof current_binding_level,
174 /* GNAT_ENTITY is a GNAT tree node for an entity. GNU_DECL is the GCC tree
175 which is to be associated with GNAT_ENTITY. Such GCC tree node is always
176 a ..._DECL node. If NO_CHECK is nonzero, the latter check is suppressed.
178 If GNU_DECL is zero, a previous association is to be reset. */
181 save_gnu_tree (gnat_entity, gnu_decl, no_check)
182 Entity_Id gnat_entity;
187 && (associate_gnat_to_gnu [gnat_entity]
188 || (! no_check && ! DECL_P (gnu_decl))))
191 associate_gnat_to_gnu [gnat_entity] = gnu_decl;
194 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
195 Return the ..._DECL node that was associated with it. If there is no tree
196 node associated with GNAT_ENTITY, abort.
198 In some cases, such as delayed elaboration or expressions that need to
199 be elaborated only once, GNAT_ENTITY is really not an entity. */
202 get_gnu_tree (gnat_entity)
203 Entity_Id gnat_entity;
205 if (! associate_gnat_to_gnu [gnat_entity])
208 return associate_gnat_to_gnu [gnat_entity];
211 /* Return nonzero if a GCC tree has been associated with GNAT_ENTITY. */
214 present_gnu_tree (gnat_entity)
215 Entity_Id gnat_entity;
217 return (associate_gnat_to_gnu [gnat_entity] != NULL_TREE);
221 /* Return non-zero if we are currently in the global binding level. */
226 return (force_global != 0 || current_binding_level == global_binding_level
230 /* Return the list of declarations in the current level. Note that this list
231 is in reverse order (it has to be so for back-end compatibility). */
236 return current_binding_level->names;
239 /* Nonzero if the current level needs to have a BLOCK made. */
244 return (current_binding_level->names != 0);
247 /* Enter a new binding level. The input parameter is ignored, but has to be
248 specified for back-end compatibility. */
252 int ignore ATTRIBUTE_UNUSED;
254 struct binding_level *newlevel = NULL;
256 /* Reuse a struct for this binding level, if there is one. */
257 if (free_binding_level)
259 newlevel = free_binding_level;
260 free_binding_level = free_binding_level->level_chain;
264 = (struct binding_level *) xmalloc (sizeof (struct binding_level));
266 *newlevel = clear_binding_level;
268 /* Add this level to the front of the chain (stack) of levels that are
270 newlevel->level_chain = current_binding_level;
271 current_binding_level = newlevel;
274 /* Exit a binding level.
275 Pop the level off, and restore the state of the identifier-decl mappings
276 that were in effect when this level was entered.
278 If KEEP is nonzero, this level had explicit declarations, so
279 and create a "block" (a BLOCK node) for the level
280 to record its declarations and subblocks for symbol table output.
282 If FUNCTIONBODY is nonzero, this level is the body of a function,
283 so create a block as if KEEP were set and also clear out all
286 If REVERSE is nonzero, reverse the order of decls before putting
287 them into the BLOCK. */
290 poplevel (keep, reverse, functionbody)
295 /* Points to a GCC BLOCK tree node. This is the BLOCK node construted for the
296 binding level that we are about to exit and which is returned by this
298 tree block = NULL_TREE;
301 tree subblock_chain = current_binding_level->blocks;
303 int block_previously_created;
305 /* Reverse the list of XXXX_DECL nodes if desired. Note that the ..._DECL
306 nodes chained through the `names' field of current_binding_level are in
307 reverse order except for PARM_DECL node, which are explicitly stored in
309 current_binding_level->names
310 = decl_chain = (reverse) ? nreverse (current_binding_level->names)
311 : current_binding_level->names;
313 /* Output any nested inline functions within this block which must be
314 compiled because their address is needed. */
315 for (decl_node = decl_chain; decl_node; decl_node = TREE_CHAIN (decl_node))
316 if (TREE_CODE (decl_node) == FUNCTION_DECL
317 && ! TREE_ASM_WRITTEN (decl_node) && TREE_ADDRESSABLE (decl_node)
318 && DECL_INITIAL (decl_node) != 0)
320 push_function_context ();
321 output_inline_function (decl_node);
322 pop_function_context ();
326 block_previously_created = (current_binding_level->this_block != 0);
327 if (block_previously_created)
328 block = current_binding_level->this_block;
329 else if (keep || functionbody)
330 block = make_node (BLOCK);
333 BLOCK_VARS (block) = keep ? decl_chain : 0;
334 BLOCK_SUBBLOCKS (block) = subblock_chain;
337 /* Record the BLOCK node just built as the subblock its enclosing scope. */
338 for (subblock_node = subblock_chain; subblock_node;
339 subblock_node = TREE_CHAIN (subblock_node))
340 BLOCK_SUPERCONTEXT (subblock_node) = block;
342 /* Clear out the meanings of the local variables of this level. */
344 for (subblock_node = decl_chain; subblock_node;
345 subblock_node = TREE_CHAIN (subblock_node))
346 if (DECL_NAME (subblock_node) != 0)
347 /* If the identifier was used or addressed via a local extern decl,
348 don't forget that fact. */
349 if (DECL_EXTERNAL (subblock_node))
351 if (TREE_USED (subblock_node))
352 TREE_USED (DECL_NAME (subblock_node)) = 1;
353 if (TREE_ADDRESSABLE (subblock_node))
354 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (subblock_node)) = 1;
358 /* Pop the current level, and free the structure for reuse. */
359 struct binding_level *level = current_binding_level;
360 current_binding_level = current_binding_level->level_chain;
361 level->level_chain = free_binding_level;
362 free_binding_level = level;
367 /* This is the top level block of a function. The ..._DECL chain stored
368 in BLOCK_VARS are the function's parameters (PARM_DECL nodes). Don't
369 leave them in the BLOCK because they are found in the FUNCTION_DECL
371 DECL_INITIAL (current_function_decl) = block;
372 BLOCK_VARS (block) = 0;
376 if (!block_previously_created)
377 current_binding_level->blocks
378 = chainon (current_binding_level->blocks, block);
381 /* If we did not make a block for the level just exited, any blocks made for
382 inner levels (since they cannot be recorded as subblocks in that level)
383 must be carried forward so they will later become subblocks of something
385 else if (subblock_chain)
386 current_binding_level->blocks
387 = chainon (current_binding_level->blocks, subblock_chain);
389 TREE_USED (block) = 1;
394 /* Insert BLOCK at the end of the list of subblocks of the
395 current binding level. This is used when a BIND_EXPR is expanded,
396 to handle the BLOCK node inside the BIND_EXPR. */
402 TREE_USED (block) = 1;
403 current_binding_level->blocks
404 = chainon (current_binding_level->blocks, block);
407 /* Set the BLOCK node for the innermost scope
408 (the one we are currently in). */
414 current_binding_level->this_block = block;
415 current_binding_level->names = chainon (current_binding_level->names,
417 current_binding_level->blocks = chainon (current_binding_level->blocks,
418 BLOCK_SUBBLOCKS (block));
421 /* Records a ..._DECL node DECL as belonging to the current lexical scope.
422 Returns the ..._DECL node. */
428 struct binding_level *b;
430 /* If at top level, there is no context. But PARM_DECLs always go in the
431 level of its function. */
432 if (global_bindings_p () && TREE_CODE (decl) != PARM_DECL)
434 b = global_binding_level;
435 DECL_CONTEXT (decl) = 0;
439 b = current_binding_level;
440 DECL_CONTEXT (decl) = current_function_decl;
443 /* Put the declaration on the list. The list of declarations is in reverse
444 order. The list will be reversed later if necessary. This needs to be
445 this way for compatibility with the back-end.
447 Don't put TYPE_DECLs for UNCONSTRAINED_ARRAY_TYPE into the list. They
448 will cause trouble with the debugger and aren't needed anyway. */
449 if (TREE_CODE (decl) != TYPE_DECL
450 || TREE_CODE (TREE_TYPE (decl)) != UNCONSTRAINED_ARRAY_TYPE)
452 TREE_CHAIN (decl) = b->names;
456 /* For the declaration of a type, set its name if it either is not already
457 set, was set to an IDENTIFIER_NODE, indicating an internal name,
458 or if the previous type name was not derived from a source name.
459 We'd rather have the type named with a real name and all the pointer
460 types to the same object have the same POINTER_TYPE node. Code in this
461 function in c-decl.c makes a copy of the type node here, but that may
462 cause us trouble with incomplete types, so let's not try it (at least
465 if (TREE_CODE (decl) == TYPE_DECL
466 && DECL_NAME (decl) != 0
467 && (TYPE_NAME (TREE_TYPE (decl)) == 0
468 || TREE_CODE (TYPE_NAME (TREE_TYPE (decl))) == IDENTIFIER_NODE
469 || (TREE_CODE (TYPE_NAME (TREE_TYPE (decl))) == TYPE_DECL
470 && DECL_ARTIFICIAL (TYPE_NAME (TREE_TYPE (decl)))
471 && ! DECL_ARTIFICIAL (decl))))
472 TYPE_NAME (TREE_TYPE (decl)) = decl;
477 /* Do little here. Set up the standard declarations later after the
478 front end has been run. */
481 gnat_init_decl_processing ()
485 /* incomplete_decl_finalize_hook is defined in toplev.c. It needs to be set
486 by each front end to the appropriate routine that handles incomplete
487 VAR_DECL nodes. This routine will be invoked by compile_file when a
488 VAR_DECL node of DECL_SIZE zero is encountered. */
489 incomplete_decl_finalize_hook = finish_incomplete_decl;
491 /* Make the binding_level structure for global names. */
492 current_function_decl = 0;
493 current_binding_level = 0;
494 free_binding_level = 0;
496 global_binding_level = current_binding_level;
498 build_common_tree_nodes (0);
500 /* In Ada, we use a signed type for SIZETYPE. Use the signed type
501 corresponding to the size of ptr_mode. Make this here since we need
502 this before we can expand the GNAT types. */
503 set_sizetype (type_for_size (GET_MODE_BITSIZE (ptr_mode), 0));
504 build_common_tree_nodes_2 (0);
506 pushdecl (build_decl (TYPE_DECL, get_identifier (SIZE_TYPE), sizetype));
508 /* We need to make the integer type before doing anything else.
509 We stitch this in to the appropriate GNAT type later. */
510 pushdecl (build_decl (TYPE_DECL, get_identifier ("integer"),
512 pushdecl (build_decl (TYPE_DECL, get_identifier ("unsigned char"),
515 ptr_void_type_node = build_pointer_type (void_type_node);
519 /* Create the predefined scalar types such as `integer_type_node' needed
520 in the gcc back-end and initialize the global binding level. */
523 init_gigi_decls (long_long_float_type, exception_type)
524 tree long_long_float_type, exception_type;
528 /* Set the types that GCC and Gigi use from the front end. We would like
529 to do this for char_type_node, but it needs to correspond to the C
531 if (TREE_CODE (TREE_TYPE (long_long_float_type)) == INTEGER_TYPE)
533 /* In this case, the builtin floating point types are VAX float,
534 so make up a type for use. */
535 longest_float_type_node = make_node (REAL_TYPE);
536 TYPE_PRECISION (longest_float_type_node) = LONG_DOUBLE_TYPE_SIZE;
537 layout_type (longest_float_type_node);
538 pushdecl (build_decl (TYPE_DECL, get_identifier ("longest float type"),
539 longest_float_type_node));
542 longest_float_type_node = TREE_TYPE (long_long_float_type);
544 except_type_node = TREE_TYPE (exception_type);
546 unsigned_type_node = type_for_size (INT_TYPE_SIZE, 1);
547 pushdecl (build_decl (TYPE_DECL, get_identifier ("unsigned int"),
548 unsigned_type_node));
551 = pushdecl (build_decl (TYPE_DECL, get_identifier ("void"),
554 void_ftype = build_function_type (void_type_node, NULL_TREE);
555 ptr_void_ftype = build_pointer_type (void_ftype);
557 /* Now declare runtime functions. */
558 endlink = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
560 /* malloc is a function declaration tree for a function to allocate
562 malloc_decl = create_subprog_decl (get_identifier ("__gnat_malloc"),
564 build_function_type (ptr_void_type_node,
565 tree_cons (NULL_TREE,
568 NULL_TREE, 0, 1, 1, 0);
570 /* free is a function declaration tree for a function to free memory. */
573 = create_subprog_decl (get_identifier ("__gnat_free"), NULL_TREE,
574 build_function_type (void_type_node,
575 tree_cons (NULL_TREE,
578 NULL_TREE, 0, 1, 1, 0);
580 /* Make the types and functions used for exception processing. */
582 = build_array_type (type_for_mode (Pmode, 0),
583 build_index_type (build_int_2 (5, 0)));
584 pushdecl (build_decl (TYPE_DECL, get_identifier ("JMPBUF_T"), jmpbuf_type));
585 jmpbuf_ptr_type = build_pointer_type (jmpbuf_type);
587 /* Functions to get and set the jumpbuf pointer for the current thread. */
589 = create_subprog_decl
590 (get_identifier ("system__soft_links__get_jmpbuf_address_soft"),
591 NULL_TREE, build_function_type (jmpbuf_ptr_type, NULL_TREE),
592 NULL_TREE, 0, 1, 1, 0);
595 = create_subprog_decl
596 (get_identifier ("system__soft_links__set_jmpbuf_address_soft"),
598 build_function_type (void_type_node,
599 tree_cons (NULL_TREE, jmpbuf_ptr_type, endlink)),
600 NULL_TREE, 0, 1, 1, 0);
602 /* Function to get the current exception. */
604 = create_subprog_decl
605 (get_identifier ("system__soft_links__get_gnat_exception"),
607 build_function_type (build_pointer_type (except_type_node), NULL_TREE),
608 NULL_TREE, 0, 1, 1, 0);
610 /* Function that raise exceptions. */
612 = create_subprog_decl
613 (get_identifier ("__gnat_raise_nodefer_with_msg"), NULL_TREE,
614 build_function_type (void_type_node,
615 tree_cons (NULL_TREE,
616 build_pointer_type (except_type_node),
618 NULL_TREE, 0, 1, 1, 0);
621 /* __gnat_raise_constraint_error takes a string, an integer and never
623 raise_constraint_error_decl
624 = create_subprog_decl
625 (get_identifier ("__gnat_raise_constraint_error"), NULL_TREE,
626 build_function_type (void_type_node,
627 tree_cons (NULL_TREE,
628 build_pointer_type (char_type_node),
629 tree_cons (NULL_TREE,
632 NULL_TREE, 0, 1, 1, 0);
634 /* Likewise for __gnat_raise_program_error. */
635 raise_program_error_decl
636 = create_subprog_decl
637 (get_identifier ("__gnat_raise_program_error"), NULL_TREE,
638 build_function_type (void_type_node,
639 tree_cons (NULL_TREE,
640 build_pointer_type (char_type_node),
641 tree_cons (NULL_TREE,
644 NULL_TREE, 0, 1, 1, 0);
646 /* Likewise for __gnat_raise_storage_error. */
647 raise_storage_error_decl
648 = create_subprog_decl
649 (get_identifier ("__gnat_raise_storage_error"), NULL_TREE,
650 build_function_type (void_type_node,
651 tree_cons (NULL_TREE,
652 build_pointer_type (char_type_node),
653 tree_cons (NULL_TREE,
656 NULL_TREE, 0, 1, 1, 0);
658 /* Indicate that these never return. */
660 TREE_THIS_VOLATILE (raise_nodefer_decl) = 1;
661 TREE_THIS_VOLATILE (raise_constraint_error_decl) = 1;
662 TREE_THIS_VOLATILE (raise_program_error_decl) = 1;
663 TREE_THIS_VOLATILE (raise_storage_error_decl) = 1;
665 TREE_SIDE_EFFECTS (raise_nodefer_decl) = 1;
666 TREE_SIDE_EFFECTS (raise_constraint_error_decl) = 1;
667 TREE_SIDE_EFFECTS (raise_program_error_decl) = 1;
668 TREE_SIDE_EFFECTS (raise_storage_error_decl) = 1;
670 TREE_TYPE (raise_nodefer_decl)
671 = build_qualified_type (TREE_TYPE (raise_nodefer_decl),
673 TREE_TYPE (raise_constraint_error_decl)
674 = build_qualified_type (TREE_TYPE (raise_constraint_error_decl),
676 TREE_TYPE (raise_program_error_decl)
677 = build_qualified_type (TREE_TYPE (raise_program_error_decl),
679 TREE_TYPE (raise_storage_error_decl)
680 = build_qualified_type (TREE_TYPE (raise_storage_error_decl),
683 /* setjmp returns an integer and has one operand, which is a pointer to
686 = create_subprog_decl
687 (get_identifier ("setjmp"), NULL_TREE,
688 build_function_type (integer_type_node,
689 tree_cons (NULL_TREE, jmpbuf_ptr_type, endlink)),
690 NULL_TREE, 0, 1, 1, 0);
692 DECL_BUILT_IN_CLASS (setjmp_decl) = BUILT_IN_NORMAL;
693 DECL_FUNCTION_CODE (setjmp_decl) = BUILT_IN_SETJMP;
695 ggc_add_tree_root (gnat_std_decls, ARRAY_SIZE (gnat_std_decls));
698 /* This routine is called in tree.c to print an error message for invalid use
699 of an incomplete type. */
702 incomplete_type_error (dont_care_1, dont_care_2)
703 tree dont_care_1 ATTRIBUTE_UNUSED;
704 tree dont_care_2 ATTRIBUTE_UNUSED;
709 /* This function is called indirectly from toplev.c to handle incomplete
710 declarations, i.e. VAR_DECL nodes whose DECL_SIZE is zero. To be precise,
711 compile_file in toplev.c makes an indirect call through the function pointer
712 incomplete_decl_finalize_hook which is initialized to this routine in
713 init_decl_processing. */
716 finish_incomplete_decl (dont_care)
717 tree dont_care ATTRIBUTE_UNUSED;
722 /* Given a record type (RECORD_TYPE) and a chain of FIELD_DECL
723 nodes (FIELDLIST), finish constructing the record or union type.
724 If HAS_REP is nonzero, this record has a rep clause; don't call
725 layout_type but merely set the size and alignment ourselves.
726 If DEFER_DEBUG is nonzero, do not call the debugging routines
727 on this type; it will be done later. */
730 finish_record_type (record_type, fieldlist, has_rep, defer_debug)
736 enum tree_code code = TREE_CODE (record_type);
737 tree ada_size = bitsize_zero_node;
738 tree size = bitsize_zero_node;
739 tree size_unit = size_zero_node;
742 TYPE_FIELDS (record_type) = fieldlist;
744 if (TYPE_NAME (record_type) != 0
745 && TREE_CODE (TYPE_NAME (record_type)) == TYPE_DECL)
746 TYPE_STUB_DECL (record_type) = TYPE_NAME (record_type);
748 TYPE_STUB_DECL (record_type)
749 = pushdecl (build_decl (TYPE_DECL, TYPE_NAME (record_type),
752 /* We don't need both the typedef name and the record name output in
753 the debugging information, since they are the same. */
754 DECL_ARTIFICIAL (TYPE_STUB_DECL (record_type)) = 1;
756 /* Globally initialize the record first. If this is a rep'ed record,
757 that just means some initializations; otherwise, layout the record. */
761 TYPE_ALIGN (record_type) = MAX (BITS_PER_UNIT, TYPE_ALIGN (record_type));
762 TYPE_MODE (record_type) = BLKmode;
763 if (TYPE_SIZE (record_type) == 0)
765 TYPE_SIZE (record_type) = bitsize_zero_node;
766 TYPE_SIZE_UNIT (record_type) = size_zero_node;
771 /* Ensure there isn't a size already set. There can be in an error
772 case where there is a rep clause but all fields have errors and
773 no longer have a position. */
774 TYPE_SIZE (record_type) = 0;
775 layout_type (record_type);
778 /* At this point, the position and size of each field is known. It was
779 either set before entry by a rep clause, or by laying out the type
780 above. We now make a pass through the fields (in reverse order for
781 QUAL_UNION_TYPEs) to compute the Ada size; the GCC size and alignment
782 (for rep'ed records that are not padding types); and the mode (for
785 if (code == QUAL_UNION_TYPE)
786 fieldlist = nreverse (fieldlist);
788 for (field = fieldlist; field; field = TREE_CHAIN (field))
790 tree type = TREE_TYPE (field);
791 tree this_size = DECL_SIZE (field);
792 tree this_size_unit = DECL_SIZE_UNIT (field);
793 tree this_ada_size = DECL_SIZE (field);
795 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
796 || TREE_CODE (type) == QUAL_UNION_TYPE)
797 && ! TYPE_IS_FAT_POINTER_P (type)
798 && ! TYPE_CONTAINS_TEMPLATE_P (type)
799 && TYPE_ADA_SIZE (type) != 0)
800 this_ada_size = TYPE_ADA_SIZE (type);
802 if (has_rep && ! DECL_BIT_FIELD (field))
803 TYPE_ALIGN (record_type)
804 = MAX (TYPE_ALIGN (record_type), DECL_ALIGN (field));
809 ada_size = size_binop (MAX_EXPR, ada_size, this_ada_size);
810 size = size_binop (MAX_EXPR, size, this_size);
811 size_unit = size_binop (MAX_EXPR, size_unit, this_size_unit);
814 case QUAL_UNION_TYPE:
816 = fold (build (COND_EXPR, bitsizetype, DECL_QUALIFIER (field),
817 this_ada_size, ada_size));
818 size = fold (build (COND_EXPR, bitsizetype, DECL_QUALIFIER (field),
820 size_unit = fold (build (COND_EXPR, sizetype, DECL_QUALIFIER (field),
821 this_size_unit, size_unit));
825 /* Since we know here that all fields are sorted in order of
826 increasing bit position, the size of the record is one
827 higher than the ending bit of the last field processed
828 unless we have a rep clause, since in that case we might
829 have a field outside a QUAL_UNION_TYPE that has a higher ending
830 position. So use a MAX in that case. Also, if this field is a
831 QUAL_UNION_TYPE, we need to take into account the previous size in
832 the case of empty variants. */
834 = merge_sizes (ada_size, bit_position (field), this_ada_size,
835 TREE_CODE (type) == QUAL_UNION_TYPE, has_rep);
836 size = merge_sizes (size, bit_position (field), this_size,
837 TREE_CODE (type) == QUAL_UNION_TYPE, has_rep);
839 = merge_sizes (size_unit, byte_position (field), this_size_unit,
840 TREE_CODE (type) == QUAL_UNION_TYPE, has_rep);
848 if (code == QUAL_UNION_TYPE)
849 nreverse (fieldlist);
851 /* If this is a padding record, we never want to make the size smaller than
852 what was specified in it, if any. */
853 if (TREE_CODE (record_type) == RECORD_TYPE
854 && TYPE_IS_PADDING_P (record_type) && TYPE_SIZE (record_type) != 0)
856 size = TYPE_SIZE (record_type);
857 size_unit = TYPE_SIZE_UNIT (record_type);
860 /* Now set any of the values we've just computed that apply. */
861 if (! TYPE_IS_FAT_POINTER_P (record_type)
862 && ! TYPE_CONTAINS_TEMPLATE_P (record_type))
863 TYPE_ADA_SIZE (record_type) = ada_size;
865 #ifdef ROUND_TYPE_SIZE
866 size = ROUND_TYPE_SIZE (record_type, size, TYPE_ALIGN (record_type));
867 size_unit = ROUND_TYPE_SIZE_UNIT (record_size, size_unit,
868 TYPE_ALIGN (record_type) / BITS_PER_UNIT);
870 size = round_up (size, TYPE_ALIGN (record_type));
871 size_unit = round_up (size_unit, TYPE_ALIGN (record_type) / BITS_PER_UNIT);
875 && ! (TREE_CODE (record_type) == RECORD_TYPE
876 && TYPE_IS_PADDING_P (record_type)
877 && TREE_CODE (size) != INTEGER_CST
878 && contains_placeholder_p (size)))
880 TYPE_SIZE (record_type) = size;
881 TYPE_SIZE_UNIT (record_type) = size_unit;
885 compute_record_mode (record_type);
889 /* If this record is of variable size, rename it so that the
890 debugger knows it is and make a new, parallel, record
891 that tells the debugger how the record is laid out. See
893 if (TREE_CODE (TYPE_SIZE (record_type)) != INTEGER_CST)
896 = make_node (TREE_CODE (record_type) == QUAL_UNION_TYPE
897 ? UNION_TYPE : TREE_CODE (record_type));
898 tree orig_id = DECL_NAME (TYPE_STUB_DECL (record_type));
900 = concat_id_with_name (orig_id,
901 TREE_CODE (record_type) == QUAL_UNION_TYPE
903 tree last_pos = bitsize_zero_node;
906 TYPE_NAME (new_record_type) = new_id;
907 TYPE_ALIGN (new_record_type) = BIGGEST_ALIGNMENT;
908 TYPE_STUB_DECL (new_record_type)
909 = pushdecl (build_decl (TYPE_DECL, new_id, new_record_type));
910 DECL_ARTIFICIAL (TYPE_STUB_DECL (new_record_type)) = 1;
911 DECL_IGNORED_P (TYPE_STUB_DECL (new_record_type))
912 = DECL_IGNORED_P (TYPE_STUB_DECL (record_type));
913 TYPE_SIZE (new_record_type) = size_int (TYPE_ALIGN (record_type));
915 /* Now scan all the fields, replacing each field with a new
916 field corresponding to the new encoding. */
917 for (old_field = TYPE_FIELDS (record_type); old_field != 0;
918 old_field = TREE_CHAIN (old_field))
920 tree field_type = TREE_TYPE (old_field);
921 tree field_name = DECL_NAME (old_field);
923 tree curpos = bit_position (old_field);
925 unsigned int align = 0;
928 /* See how the position was modified from the last position.
930 There are two basic cases we support: a value was added
931 to the last position or the last position was rounded to
932 a boundary and they something was added. Check for the
933 first case first. If not, see if there is any evidence
934 of rounding. If so, round the last position and try
937 If this is a union, the position can be taken as zero. */
939 if (TREE_CODE (new_record_type) == UNION_TYPE)
940 pos = bitsize_zero_node, align = 0;
942 pos = compute_related_constant (curpos, last_pos);
944 if (pos == 0 && TREE_CODE (curpos) == MULT_EXPR
945 && TREE_CODE (TREE_OPERAND (curpos, 1)) == INTEGER_CST)
947 align = TREE_INT_CST_LOW (TREE_OPERAND (curpos, 1));
948 pos = compute_related_constant (curpos,
949 round_up (last_pos, align));
951 else if (pos == 0 && TREE_CODE (curpos) == PLUS_EXPR
952 && TREE_CODE (TREE_OPERAND (curpos, 1)) == INTEGER_CST
953 && TREE_CODE (TREE_OPERAND (curpos, 0)) == MULT_EXPR
954 && host_integerp (TREE_OPERAND
955 (TREE_OPERAND (curpos, 0), 1),
960 (TREE_OPERAND (TREE_OPERAND (curpos, 0), 1), 1);
961 pos = compute_related_constant (curpos,
962 round_up (last_pos, align));
965 /* If we can't compute a position, set it to zero.
967 ??? We really should abort here, but it's too much work
968 to get this correct for all cases. */
971 pos = bitsize_zero_node;
973 /* See if this type is variable-size and make a new type
974 and indicate the indirection if so. */
975 if (TREE_CODE (TYPE_SIZE (field_type)) != INTEGER_CST)
977 field_type = build_pointer_type (field_type);
981 /* Make a new field name, if necessary. */
982 if (var || align != 0)
987 sprintf (suffix, "XV%c%u", var ? 'L' : 'A',
988 align / BITS_PER_UNIT);
990 strcpy (suffix, "XVL");
992 field_name = concat_id_with_name (field_name, suffix);
995 new_field = create_field_decl (field_name, field_type,
997 TYPE_SIZE (field_type), pos, 0);
998 TREE_CHAIN (new_field) = TYPE_FIELDS (new_record_type);
999 TYPE_FIELDS (new_record_type) = new_field;
1001 /* If old_field is a QUAL_UNION_TYPE, take its size as being
1002 zero. The only time it's not the last field of the record
1003 is when there are other components at fixed positions after
1004 it (meaning there was a rep clause for every field) and we
1005 want to be able to encode them. */
1006 last_pos = size_binop (PLUS_EXPR, bit_position (old_field),
1007 (TREE_CODE (TREE_TYPE (old_field))
1010 : TYPE_SIZE (TREE_TYPE (old_field)));
1013 TYPE_FIELDS (new_record_type)
1014 = nreverse (TYPE_FIELDS (new_record_type));
1016 rest_of_type_compilation (new_record_type, global_bindings_p ());
1019 rest_of_type_compilation (record_type, global_bindings_p ());
1023 /* Utility function of above to merge LAST_SIZE, the previous size of a record
1024 with FIRST_BIT and SIZE that describe a field. SPECIAL is nonzero
1025 if this represents a QUAL_UNION_TYPE in which case we must look for
1026 COND_EXPRs and replace a value of zero with the old size. If HAS_REP
1027 is nonzero, we must take the MAX of the end position of this field
1028 with LAST_SIZE. In all other cases, we use FIRST_BIT plus SIZE.
1030 We return an expression for the size. */
1033 merge_sizes (last_size, first_bit, size, special, has_rep)
1035 tree first_bit, size;
1039 tree type = TREE_TYPE (last_size);
1041 if (! special || TREE_CODE (size) != COND_EXPR)
1043 tree new = size_binop (PLUS_EXPR, first_bit, size);
1046 new = size_binop (MAX_EXPR, last_size, new);
1051 return fold (build (COND_EXPR, type, TREE_OPERAND (size, 0),
1052 integer_zerop (TREE_OPERAND (size, 1))
1053 ? last_size : merge_sizes (last_size, first_bit,
1054 TREE_OPERAND (size, 1),
1056 integer_zerop (TREE_OPERAND (size, 2))
1057 ? last_size : merge_sizes (last_size, first_bit,
1058 TREE_OPERAND (size, 2),
1062 /* Utility function of above to see if OP0 and OP1, both of SIZETYPE, are
1063 related by the addition of a constant. Return that constant if so. */
1066 compute_related_constant (op0, op1)
1069 tree op0_var, op1_var;
1070 tree op0_con = split_plus (op0, &op0_var);
1071 tree op1_con = split_plus (op1, &op1_var);
1072 tree result = size_binop (MINUS_EXPR, op0_con, op1_con);
1074 if (operand_equal_p (op0_var, op1_var, 0))
1076 else if (operand_equal_p (op0, size_binop (PLUS_EXPR, op1_var, result), 0))
1082 /* Utility function of above to split a tree OP which may be a sum, into a
1083 constant part, which is returned, and a variable part, which is stored
1084 in *PVAR. *PVAR may be size_zero_node. All operations must be of
1088 split_plus (in, pvar)
1092 tree result = bitsize_zero_node;
1094 while (TREE_CODE (in) == NON_LVALUE_EXPR)
1095 in = TREE_OPERAND (in, 0);
1098 if (TREE_CODE (in) == INTEGER_CST)
1100 *pvar = bitsize_zero_node;
1103 else if (TREE_CODE (in) == PLUS_EXPR || TREE_CODE (in) == MINUS_EXPR)
1105 tree lhs_var, rhs_var;
1106 tree lhs_con = split_plus (TREE_OPERAND (in, 0), &lhs_var);
1107 tree rhs_con = split_plus (TREE_OPERAND (in, 1), &rhs_var);
1109 result = size_binop (PLUS_EXPR, result, lhs_con);
1110 result = size_binop (TREE_CODE (in), result, rhs_con);
1112 if (lhs_var == TREE_OPERAND (in, 0)
1113 && rhs_var == TREE_OPERAND (in, 1))
1114 return bitsize_zero_node;
1116 *pvar = size_binop (TREE_CODE (in), lhs_var, rhs_var);
1120 return bitsize_zero_node;
1123 /* Return a FUNCTION_TYPE node. RETURN_TYPE is the type returned by the
1124 subprogram. If it is void_type_node, then we are dealing with a procedure,
1125 otherwise we are dealing with a function. PARAM_DECL_LIST is a list of
1126 PARM_DECL nodes that are the subprogram arguments. CICO_LIST is the
1127 copy-in/copy-out list to be stored into TYPE_CICO_LIST.
1128 RETURNS_UNCONSTRAINED is nonzero if the function returns an unconstrained
1129 object. RETURNS_BY_REF is nonzero if the function returns by reference.
1130 RETURNS_WITH_DSP is nonzero if the function is to return with a
1131 depressed stack pointer. */
1134 create_subprog_type (return_type, param_decl_list, cico_list,
1135 returns_unconstrained, returns_by_ref, returns_with_dsp)
1137 tree param_decl_list;
1139 int returns_unconstrained, returns_by_ref, returns_with_dsp;
1141 /* A chain of TREE_LIST nodes whose TREE_VALUEs are the data type nodes of
1142 the subprogram formal parameters. This list is generated by traversing the
1143 input list of PARM_DECL nodes. */
1144 tree param_type_list = NULL;
1148 for (param_decl = param_decl_list; param_decl;
1149 param_decl = TREE_CHAIN (param_decl))
1150 param_type_list = tree_cons (NULL_TREE, TREE_TYPE (param_decl),
1153 /* The list of the function parameter types has to be terminated by the void
1154 type to signal to the back-end that we are not dealing with a variable
1155 parameter subprogram, but that the subprogram has a fixed number of
1157 param_type_list = tree_cons (NULL_TREE, void_type_node, param_type_list);
1159 /* The list of argument types has been created in reverse
1161 param_type_list = nreverse (param_type_list);
1163 type = build_function_type (return_type, param_type_list);
1165 /* TYPE may have been shared since GCC hashes types. If it has a CICO_LIST
1166 or the new type should, make a copy of TYPE. Likewise for
1167 RETURNS_UNCONSTRAINED and RETURNS_BY_REF. */
1168 if (TYPE_CI_CO_LIST (type) != 0 || cico_list != 0
1169 || TYPE_RETURNS_UNCONSTRAINED_P (type) != returns_unconstrained
1170 || TYPE_RETURNS_BY_REF_P (type) != returns_by_ref)
1171 type = copy_type (type);
1173 TYPE_CI_CO_LIST (type) = cico_list;
1174 TYPE_RETURNS_UNCONSTRAINED_P (type) = returns_unconstrained;
1175 TYPE_RETURNS_STACK_DEPRESSED (type) = returns_with_dsp;
1176 TYPE_RETURNS_BY_REF_P (type) = returns_by_ref;
1180 /* Return a copy of TYPE but safe to modify in any way. */
1186 tree new = copy_node (type);
1188 /* copy_node clears this field instead of copying it, because it is
1189 aliased with TREE_CHAIN. */
1190 TYPE_STUB_DECL (new) = TYPE_STUB_DECL (type);
1192 TYPE_POINTER_TO (new) = 0;
1193 TYPE_REFERENCE_TO (new) = 0;
1194 TYPE_MAIN_VARIANT (new) = new;
1195 TYPE_NEXT_VARIANT (new) = 0;
1200 /* Return an INTEGER_TYPE of SIZETYPE with range MIN to MAX and whose
1201 TYPE_INDEX_TYPE is INDEX. */
1204 create_index_type (min, max, index)
1208 /* First build a type for the desired range. */
1209 tree type = build_index_2_type (min, max);
1211 /* If this type has the TYPE_INDEX_TYPE we want, return it. Otherwise, if it
1212 doesn't have TYPE_INDEX_TYPE set, set it to INDEX. If TYPE_INDEX_TYPE
1213 is set, but not to INDEX, make a copy of this type with the requested
1214 index type. Note that we have no way of sharing these types, but that's
1215 only a small hole. */
1216 if (TYPE_INDEX_TYPE (type) == index)
1218 else if (TYPE_INDEX_TYPE (type) != 0)
1219 type = copy_type (type);
1221 TYPE_INDEX_TYPE (type) = index;
1225 /* Return a TYPE_DECL node. TYPE_NAME gives the name of the type (a character
1226 string) and TYPE is a ..._TYPE node giving its data type.
1227 ARTIFICIAL_P is nonzero if this is a declaration that was generated
1228 by the compiler. DEBUG_INFO_P is nonzero if we need to write debugging
1229 information about this type. */
1232 create_type_decl (type_name, type, attr_list, artificial_p, debug_info_p)
1235 struct attrib *attr_list;
1239 tree type_decl = build_decl (TYPE_DECL, type_name, type);
1240 enum tree_code code = TREE_CODE (type);
1242 DECL_ARTIFICIAL (type_decl) = artificial_p;
1243 pushdecl (type_decl);
1244 process_attributes (type_decl, attr_list);
1246 /* Pass type declaration information to the debugger unless this is an
1247 UNCONSTRAINED_ARRAY_TYPE, which the debugger does not support,
1248 and ENUMERAL_TYPE or RECORD_TYPE which is handled separately,
1249 a dummy type, which will be completed later, or a type for which
1250 debugging information was not requested. */
1251 if (code == UNCONSTRAINED_ARRAY_TYPE || TYPE_IS_DUMMY_P (type)
1253 DECL_IGNORED_P (type_decl) = 1;
1254 else if (code != ENUMERAL_TYPE && code != RECORD_TYPE
1255 && ! ((code == POINTER_TYPE || code == REFERENCE_TYPE)
1256 && TYPE_IS_DUMMY_P (TREE_TYPE (type))))
1257 rest_of_decl_compilation (type_decl, NULL, global_bindings_p (), 0);
1262 /* Returns a GCC VAR_DECL node. VAR_NAME gives the name of the variable.
1263 ASM_NAME is its assembler name (if provided). TYPE is its data type
1264 (a GCC ..._TYPE node). VAR_INIT is the GCC tree for an optional initial
1265 expression; NULL_TREE if none.
1267 CONST_FLAG is nonzero if this variable is constant.
1269 PUBLIC_FLAG is nonzero if this definition is to be made visible outside of
1270 the current compilation unit. This flag should be set when processing the
1271 variable definitions in a package specification. EXTERN_FLAG is nonzero
1272 when processing an external variable declaration (as opposed to a
1273 definition: no storage is to be allocated for the variable here).
1275 STATIC_FLAG is only relevant when not at top level. In that case
1276 it indicates whether to always allocate storage to the variable. */
1279 create_var_decl (var_name, asm_name, type, var_init, const_flag, public_flag,
1280 extern_flag, static_flag, attr_list)
1289 struct attrib *attr_list;
1294 : (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (var_init))
1295 && (global_bindings_p () || static_flag
1296 ? 0 != initializer_constant_valid_p (var_init,
1297 TREE_TYPE (var_init))
1298 : TREE_CONSTANT (var_init))));
1300 = build_decl ((const_flag && init_const
1301 /* Only make a CONST_DECL for sufficiently-small objects.
1302 We consider complex double "sufficiently-small" */
1303 && TYPE_SIZE (type) != 0
1304 && host_integerp (TYPE_SIZE_UNIT (type), 1)
1305 && 0 >= compare_tree_int (TYPE_SIZE_UNIT (type),
1306 GET_MODE_SIZE (DCmode)))
1307 ? CONST_DECL : VAR_DECL, var_name, type);
1308 tree assign_init = 0;
1310 /* If this is external, throw away any initializations unless this is a
1311 CONST_DECL (meaning we have a constant); they will be done elsewhere. If
1312 we are defining a global here, leave a constant initialization and save
1313 any variable elaborations for the elaboration routine. Otherwise, if
1314 the initializing expression is not the same as TYPE, generate the
1315 initialization with an assignment statement, since it knows how
1316 to do the required adjustents. If we are just annotating types,
1317 throw away the initialization if it isn't a constant. */
1319 if ((extern_flag && TREE_CODE (var_decl) != CONST_DECL)
1320 || (type_annotate_only && var_init != 0 && ! TREE_CONSTANT (var_init)))
1323 if (global_bindings_p () && var_init != 0 && ! init_const)
1325 add_pending_elaborations (var_decl, var_init);
1329 else if (var_init != 0
1330 && ((TYPE_MAIN_VARIANT (TREE_TYPE (var_init))
1331 != TYPE_MAIN_VARIANT (type))
1332 || (static_flag && ! init_const)))
1333 assign_init = var_init, var_init = 0;
1335 DECL_COMMON (var_decl) = !flag_no_common;
1336 DECL_INITIAL (var_decl) = var_init;
1337 TREE_READONLY (var_decl) = const_flag;
1338 DECL_EXTERNAL (var_decl) = extern_flag;
1339 TREE_PUBLIC (var_decl) = public_flag || extern_flag;
1340 TREE_CONSTANT (var_decl) = TREE_CODE (var_decl) == CONST_DECL;
1341 TREE_THIS_VOLATILE (var_decl) = TREE_SIDE_EFFECTS (var_decl)
1342 = TYPE_VOLATILE (type);
1344 /* At the global binding level we need to allocate static storage for the
1345 variable if and only if its not external. If we are not at the top level
1346 we allocate automatic storage unless requested not to. */
1347 TREE_STATIC (var_decl) = global_bindings_p () ? !extern_flag : static_flag;
1350 SET_DECL_ASSEMBLER_NAME (var_decl, asm_name);
1352 process_attributes (var_decl, attr_list);
1354 /* Add this decl to the current binding level and generate any
1355 needed code and RTL. */
1356 var_decl = pushdecl (var_decl);
1357 expand_decl (var_decl);
1359 if (DECL_CONTEXT (var_decl) != 0)
1360 expand_decl_init (var_decl);
1362 /* If this is volatile, force it into memory. */
1363 if (TREE_SIDE_EFFECTS (var_decl))
1364 mark_addressable (var_decl);
1366 if (TREE_CODE (var_decl) != CONST_DECL)
1367 rest_of_decl_compilation (var_decl, 0, global_bindings_p (), 0);
1369 if (assign_init != 0)
1371 /* If VAR_DECL has a padded type, convert it to the unpadded
1372 type so the assignment is done properly. */
1373 tree lhs = var_decl;
1375 if (TREE_CODE (TREE_TYPE (lhs)) == RECORD_TYPE
1376 && TYPE_IS_PADDING_P (TREE_TYPE (lhs)))
1377 lhs = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (lhs))), lhs);
1379 expand_expr_stmt (build_binary_op (MODIFY_EXPR, NULL_TREE, lhs,
1386 /* Returns a FIELD_DECL node. FIELD_NAME the field name, FIELD_TYPE is its
1387 type, and RECORD_TYPE is the type of the parent. PACKED is nonzero if
1388 this field is in a record type with a "pragma pack". If SIZE is nonzero
1389 it is the specified size for this field. If POS is nonzero, it is the bit
1390 position. If ADDRESSABLE is nonzero, it means we are allowed to take
1391 the address of this field for aliasing purposes. */
1394 create_field_decl (field_name, field_type, record_type, packed, size, pos,
1403 tree field_decl = build_decl (FIELD_DECL, field_name, field_type);
1405 DECL_CONTEXT (field_decl) = record_type;
1406 TREE_READONLY (field_decl) = TREE_READONLY (field_type);
1408 /* If FIELD_TYPE is BLKmode, we must ensure this is aligned to at least a
1409 byte boundary since GCC cannot handle less-aligned BLKmode bitfields.
1410 If it is a padding type where the inner field is of variable size, it
1411 must be at its natural alignment. Just handle the packed case here; we
1412 will disallow non-aligned rep clauses elsewhere. */
1413 if (packed && TYPE_MODE (field_type) == BLKmode)
1414 DECL_ALIGN (field_decl)
1415 = ((TREE_CODE (field_type) == RECORD_TYPE
1416 && TYPE_IS_PADDING_P (field_type)
1417 && ! TREE_CONSTANT (DECL_SIZE (TYPE_FIELDS (field_type))))
1418 ? TYPE_ALIGN (field_type) : BITS_PER_UNIT);
1420 /* If a size is specified, use it. Otherwise, see if we have a size
1421 to use that may differ from the natural size of the object. */
1423 size = convert (bitsizetype, size);
1426 if (packed == 1 && ! operand_equal_p (rm_size (field_type),
1427 TYPE_SIZE (field_type), 0))
1428 size = rm_size (field_type);
1430 /* For a constant size larger than MAX_FIXED_MODE_SIZE, round up to
1432 if (size != 0 && TREE_CODE (size) == INTEGER_CST
1433 && compare_tree_int (size, MAX_FIXED_MODE_SIZE) > 0)
1434 size = round_up (size, BITS_PER_UNIT);
1437 /* Make a bitfield if a size is specified for two reasons: first if the size
1438 differs from the natural size. Second, if the alignment is insufficient.
1439 There are a number of ways the latter can be true. But never make a
1440 bitfield if the type of the field has a nonconstant size. */
1442 if (size != 0 && TREE_CODE (size) == INTEGER_CST
1443 && TREE_CODE (TYPE_SIZE (field_type)) == INTEGER_CST
1444 && (! operand_equal_p (TYPE_SIZE (field_type), size, 0)
1446 && ! value_zerop (size_binop (TRUNC_MOD_EXPR, pos,
1447 bitsize_int (TYPE_ALIGN
1450 || (TYPE_ALIGN (record_type) != 0
1451 && TYPE_ALIGN (record_type) < TYPE_ALIGN (field_type))))
1453 DECL_BIT_FIELD (field_decl) = 1;
1454 DECL_SIZE (field_decl) = size;
1455 if (! packed && pos == 0)
1456 DECL_ALIGN (field_decl)
1457 = (TYPE_ALIGN (record_type) != 0
1458 ? MIN (TYPE_ALIGN (record_type), TYPE_ALIGN (field_type))
1459 : TYPE_ALIGN (field_type));
1462 DECL_PACKED (field_decl) = pos != 0 ? DECL_BIT_FIELD (field_decl) : packed;
1463 DECL_ALIGN (field_decl)
1464 = MAX (DECL_ALIGN (field_decl),
1465 DECL_BIT_FIELD (field_decl) ? 1
1466 : packed && TYPE_MODE (field_type) != BLKmode ? BITS_PER_UNIT
1467 : TYPE_ALIGN (field_type));
1471 /* We need to pass in the alignment the DECL is known to have.
1472 This is the lowest-order bit set in POS, but no more than
1473 the alignment of the record, if one is specified. Note
1474 that an alignment of 0 is taken as infinite. */
1475 unsigned int known_align;
1477 if (host_integerp (pos, 1))
1478 known_align = tree_low_cst (pos, 1) & - tree_low_cst (pos, 1);
1480 known_align = BITS_PER_UNIT;
1482 if (TYPE_ALIGN (record_type)
1483 && (known_align == 0 || known_align > TYPE_ALIGN (record_type)))
1484 known_align = TYPE_ALIGN (record_type);
1486 layout_decl (field_decl, known_align);
1487 SET_DECL_OFFSET_ALIGN (field_decl, BIGGEST_ALIGNMENT);
1488 pos_from_bit (&DECL_FIELD_OFFSET (field_decl),
1489 &DECL_FIELD_BIT_OFFSET (field_decl),
1490 BIGGEST_ALIGNMENT, pos);
1492 DECL_HAS_REP_P (field_decl) = 1;
1495 /* Mark the decl as nonaddressable if it either is indicated so semantically
1496 or if it is a bit field. */
1497 DECL_NONADDRESSABLE_P (field_decl)
1498 = ! addressable || DECL_BIT_FIELD (field_decl);
1503 /* Subroutine of previous function: return nonzero if EXP, ignoring any side
1504 effects, has the value of zero. */
1510 if (TREE_CODE (exp) == COMPOUND_EXPR)
1511 return value_zerop (TREE_OPERAND (exp, 1));
1513 return integer_zerop (exp);
1516 /* Returns a PARM_DECL node. PARAM_NAME is the name of the parameter,
1517 PARAM_TYPE is its type. READONLY is nonzero if the parameter is
1518 readonly (either an IN parameter or an address of a pass-by-ref
1522 create_param_decl (param_name, param_type, readonly)
1527 tree param_decl = build_decl (PARM_DECL, param_name, param_type);
1529 DECL_ARG_TYPE (param_decl) = param_type;
1530 DECL_ARG_TYPE_AS_WRITTEN (param_decl) = param_type;
1531 TREE_READONLY (param_decl) = readonly;
1535 /* Given a DECL and ATTR_LIST, process the listed attributes. */
1538 process_attributes (decl, attr_list)
1540 struct attrib *attr_list;
1542 for (; attr_list; attr_list = attr_list->next)
1543 switch (attr_list->type)
1545 case ATTR_MACHINE_ATTRIBUTE:
1546 decl_attributes (&decl, tree_cons (attr_list->name, attr_list->arg,
1548 ATTR_FLAG_TYPE_IN_PLACE);
1551 case ATTR_LINK_ALIAS:
1552 TREE_STATIC (decl) = 1;
1553 assemble_alias (decl, attr_list->name);
1556 case ATTR_WEAK_EXTERNAL:
1558 declare_weak (decl);
1560 post_error ("?weak declarations not supported on this target",
1561 attr_list->error_point);
1564 case ATTR_LINK_SECTION:
1565 #ifdef ASM_OUTPUT_SECTION_NAME
1566 DECL_SECTION_NAME (decl)
1567 = build_string (IDENTIFIER_LENGTH (attr_list->name),
1568 IDENTIFIER_POINTER (attr_list->name));
1569 DECL_COMMON (decl) = 0;
1571 post_error ("?section attributes are not supported for this target",
1572 attr_list->error_point);
1578 /* Add some pending elaborations on the list. */
1581 add_pending_elaborations (var_decl, var_init)
1586 Check_Elaboration_Code_Allowed (error_gnat_node);
1588 pending_elaborations
1589 = chainon (pending_elaborations, build_tree_list (var_decl, var_init));
1592 /* Obtain any pending elaborations and clear the old list. */
1595 get_pending_elaborations ()
1597 /* Each thing added to the list went on the end; we want it on the
1599 tree result = TREE_CHAIN (pending_elaborations);
1601 TREE_CHAIN (pending_elaborations) = 0;
1605 /* Mark the binding level stack. */
1608 mark_binding_level (arg)
1611 struct binding_level *level = *(struct binding_level **) arg;
1613 for (; level != 0; level = level->level_chain)
1615 ggc_mark_tree (level->names);
1616 ggc_mark_tree (level->blocks);
1617 ggc_mark_tree (level->this_block);
1621 /* Mark the pending elaboration list. */
1627 struct e_stack *p = *((struct e_stack **) data);
1631 ggc_mark_tree (p->elab_list);
1632 mark_e_stack (&p->next);
1636 /* Return nonzero if there are pending elaborations. */
1639 pending_elaborations_p ()
1641 return TREE_CHAIN (pending_elaborations) != 0;
1644 /* Save a copy of the current pending elaboration list and make a new
1648 push_pending_elaborations ()
1650 struct e_stack *p = (struct e_stack *) xmalloc (sizeof (struct e_stack));
1652 p->next = elist_stack;
1653 p->elab_list = pending_elaborations;
1655 pending_elaborations = build_tree_list (NULL_TREE, NULL_TREE);
1658 /* Pop the stack of pending elaborations. */
1661 pop_pending_elaborations ()
1663 struct e_stack *p = elist_stack;
1665 pending_elaborations = p->elab_list;
1666 elist_stack = p->next;
1670 /* Return the current position in pending_elaborations so we can insert
1671 elaborations after that point. */
1674 get_elaboration_location ()
1676 return tree_last (pending_elaborations);
1679 /* Insert the current elaborations after ELAB, which is in some elaboration
1683 insert_elaboration_list (elab)
1686 tree next = TREE_CHAIN (elab);
1688 if (TREE_CHAIN (pending_elaborations))
1690 TREE_CHAIN (elab) = TREE_CHAIN (pending_elaborations);
1691 TREE_CHAIN (tree_last (pending_elaborations)) = next;
1692 TREE_CHAIN (pending_elaborations) = 0;
1696 /* Returns a LABEL_DECL node for LABEL_NAME. */
1699 create_label_decl (label_name)
1702 tree label_decl = build_decl (LABEL_DECL, label_name, void_type_node);
1704 DECL_CONTEXT (label_decl) = current_function_decl;
1705 DECL_MODE (label_decl) = VOIDmode;
1706 DECL_SOURCE_LINE (label_decl) = lineno;
1707 DECL_SOURCE_FILE (label_decl) = input_filename;
1712 /* Returns a FUNCTION_DECL node. SUBPROG_NAME is the name of the subprogram,
1713 ASM_NAME is its assembler name, SUBPROG_TYPE is its type (a FUNCTION_TYPE
1714 node), PARAM_DECL_LIST is the list of the subprogram arguments (a list of
1715 PARM_DECL nodes chained through the TREE_CHAIN field).
1717 INLINE_FLAG, PUBLIC_FLAG, and EXTERN_FLAG are used to set the appropriate
1718 fields in the FUNCTION_DECL. */
1721 create_subprog_decl (subprog_name, asm_name, subprog_type, param_decl_list,
1722 inline_flag, public_flag, extern_flag, attr_list)
1726 tree param_decl_list;
1730 struct attrib *attr_list;
1732 tree return_type = TREE_TYPE (subprog_type);
1733 tree subprog_decl = build_decl (FUNCTION_DECL, subprog_name, subprog_type);
1735 /* If this is a function nested inside an inlined external function, it
1736 means we aren't going to compile the outer function unless it is
1737 actually inlined, so do the same for us. */
1738 if (current_function_decl != 0 && DECL_INLINE (current_function_decl)
1739 && DECL_EXTERNAL (current_function_decl))
1742 DECL_EXTERNAL (subprog_decl) = extern_flag;
1743 TREE_PUBLIC (subprog_decl) = public_flag;
1744 DECL_INLINE (subprog_decl) = inline_flag;
1745 TREE_READONLY (subprog_decl) = TYPE_READONLY (subprog_type);
1746 TREE_THIS_VOLATILE (subprog_decl) = TYPE_VOLATILE (subprog_type);
1747 TREE_SIDE_EFFECTS (subprog_decl) = TYPE_VOLATILE (subprog_type);
1748 DECL_ARGUMENTS (subprog_decl) = param_decl_list;
1749 DECL_RESULT (subprog_decl) = build_decl (RESULT_DECL, 0, return_type);
1752 DECL_ASSEMBLER_NAME (subprog_decl) = asm_name;
1754 process_attributes (subprog_decl, attr_list);
1756 /* Add this decl to the current binding level. */
1757 subprog_decl = pushdecl (subprog_decl);
1759 /* Output the assembler code and/or RTL for the declaration. */
1760 rest_of_decl_compilation (subprog_decl, 0, global_bindings_p (), 0);
1762 return subprog_decl;
1765 /* Count how deep we are into nested functions. This is because
1766 we shouldn't call the backend function context routines unless we
1767 are in a nested function. */
1769 static int function_nesting_depth;
1771 /* Set up the framework for generating code for SUBPROG_DECL, a subprogram
1772 body. This routine needs to be invoked before processing the declarations
1773 appearing in the subprogram. */
1776 begin_subprog_body (subprog_decl)
1779 tree param_decl_list;
1783 if (function_nesting_depth++ != 0)
1784 push_function_context ();
1786 announce_function (subprog_decl);
1788 /* Make this field nonzero so further routines know that this is not
1789 tentative. error_mark_node is replaced below (in poplevel) with the
1791 DECL_INITIAL (subprog_decl) = error_mark_node;
1793 /* This function exists in static storage. This does not mean `static' in
1795 TREE_STATIC (subprog_decl) = 1;
1797 /* Enter a new binding level. */
1798 current_function_decl = subprog_decl;
1801 /* Push all the PARM_DECL nodes onto the current scope (i.e. the scope of the
1802 subprogram body) so that they can be recognized as local variables in the
1805 The list of PARM_DECL nodes is stored in the right order in
1806 DECL_ARGUMENTS. Since ..._DECL nodes get stored in the reverse order in
1807 which they are transmitted to `pushdecl' we need to reverse the list of
1808 PARM_DECLs if we want it to be stored in the right order. The reason why
1809 we want to make sure the PARM_DECLs are stored in the correct order is
1810 that this list will be retrieved in a few lines with a call to `getdecl'
1811 to store it back into the DECL_ARGUMENTS field. */
1812 param_decl_list = nreverse (DECL_ARGUMENTS (subprog_decl));
1814 for (param_decl = param_decl_list; param_decl; param_decl = next_param)
1816 next_param = TREE_CHAIN (param_decl);
1817 TREE_CHAIN (param_decl) = NULL;
1818 pushdecl (param_decl);
1821 /* Store back the PARM_DECL nodes. They appear in the right order. */
1822 DECL_ARGUMENTS (subprog_decl) = getdecls ();
1824 init_function_start (subprog_decl, input_filename, lineno);
1825 expand_function_start (subprog_decl, 0);
1829 /* Finish the definition of the current subprogram and compile it all the way
1830 to assembler language output. */
1839 BLOCK_SUPERCONTEXT (DECL_INITIAL (current_function_decl))
1840 = current_function_decl;
1842 /* Mark the RESULT_DECL as being in this subprogram. */
1843 DECL_CONTEXT (DECL_RESULT (current_function_decl)) = current_function_decl;
1845 expand_function_end (input_filename, lineno, 0);
1847 /* If this is a nested function, push a new GC context. That will keep
1848 local variables on the stack from being collected while we're doing
1849 the compilation of this function. */
1850 if (function_nesting_depth > 1)
1851 ggc_push_context ();
1853 rest_of_compilation (current_function_decl);
1855 if (function_nesting_depth > 1)
1859 /* If we're sure this function is defined in this file then mark it
1861 if (TREE_ASM_WRITTEN (current_function_decl))
1862 mark_fn_defined_in_this_file (current_function_decl);
1865 /* Throw away any VAR_DECLs we made for OUT parameters; they must
1866 not be seen when we call this function and will be in
1867 unallocated memory anyway. */
1868 for (cico_list = TYPE_CI_CO_LIST (TREE_TYPE (current_function_decl));
1869 cico_list != 0; cico_list = TREE_CHAIN (cico_list))
1870 TREE_VALUE (cico_list) = 0;
1872 if (DECL_SAVED_INSNS (current_function_decl) == 0)
1874 /* Throw away DECL_RTL in any PARM_DECLs unless this function
1875 was saved for inline, in which case the DECL_RTLs are in
1876 preserved memory. */
1877 for (decl = DECL_ARGUMENTS (current_function_decl);
1878 decl != 0; decl = TREE_CHAIN (decl))
1880 SET_DECL_RTL (decl, 0);
1881 DECL_INCOMING_RTL (decl) = 0;
1884 /* Similarly, discard DECL_RTL of the return value. */
1885 SET_DECL_RTL (DECL_RESULT (current_function_decl), 0);
1887 /* But DECL_INITIAL must remain nonzero so we know this
1888 was an actual function definition unless toplev.c decided not
1890 if (DECL_INITIAL (current_function_decl) != 0)
1891 DECL_INITIAL (current_function_decl) = error_mark_node;
1893 DECL_ARGUMENTS (current_function_decl) = 0;
1896 /* If we are not at the bottom of the function nesting stack, pop up to
1897 the containing function. Otherwise show we aren't in any function. */
1898 if (--function_nesting_depth != 0)
1899 pop_function_context ();
1901 current_function_decl = 0;
1904 /* Return a definition for a builtin function named NAME and whose data type
1905 is TYPE. TYPE should be a function type with argument types.
1906 FUNCTION_CODE tells later passes how to compile calls to this function.
1907 See tree.h for its possible values.
1909 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
1910 the name to be called if we can't opencode the function. */
1913 builtin_function (name, type, function_code, class, library_name)
1917 enum built_in_class class;
1918 const char *library_name;
1920 tree decl = build_decl (FUNCTION_DECL, get_identifier (name), type);
1922 DECL_EXTERNAL (decl) = 1;
1923 TREE_PUBLIC (decl) = 1;
1925 DECL_ASSEMBLER_NAME (decl) = get_identifier (library_name);
1928 DECL_BUILT_IN_CLASS (decl) = class;
1929 DECL_FUNCTION_CODE (decl) = function_code;
1933 /* Return an integer type with the number of bits of precision given by
1934 PRECISION. UNSIGNEDP is nonzero if the type is unsigned; otherwise
1935 it is a signed type. */
1938 type_for_size (precision, unsignedp)
1945 if (precision <= 2 * MAX_BITS_PER_WORD
1946 && signed_and_unsigned_types[precision][unsignedp] != 0)
1947 return signed_and_unsigned_types[precision][unsignedp];
1950 t = make_unsigned_type (precision);
1952 t = make_signed_type (precision);
1954 if (precision <= 2 * MAX_BITS_PER_WORD)
1955 signed_and_unsigned_types[precision][unsignedp] = t;
1957 if (TYPE_NAME (t) == 0)
1959 sprintf (type_name, "%sSIGNED_%d", unsignedp ? "UN" : "", precision);
1960 TYPE_NAME (t) = get_identifier (type_name);
1966 /* Likewise for floating-point types. */
1969 float_type_for_size (precision, mode)
1971 enum machine_mode mode;
1976 if (float_types[(int) mode] != 0)
1977 return float_types[(int) mode];
1979 float_types[(int) mode] = t = make_node (REAL_TYPE);
1980 TYPE_PRECISION (t) = precision;
1983 if (TYPE_MODE (t) != mode)
1986 if (TYPE_NAME (t) == 0)
1988 sprintf (type_name, "FLOAT_%d", precision);
1989 TYPE_NAME (t) = get_identifier (type_name);
1995 /* Return a data type that has machine mode MODE. UNSIGNEDP selects
1996 an unsigned type; otherwise a signed type is returned. */
1999 type_for_mode (mode, unsignedp)
2000 enum machine_mode mode;
2003 if (GET_MODE_CLASS (mode) == MODE_FLOAT)
2004 return float_type_for_size (GET_MODE_BITSIZE (mode), mode);
2006 return type_for_size (GET_MODE_BITSIZE (mode), unsignedp);
2009 /* Return the unsigned version of a TYPE_NODE, a scalar type. */
2012 unsigned_type (type_node)
2015 tree type = type_for_size (TYPE_PRECISION (type_node), 1);
2017 if (TREE_CODE (type_node) == INTEGER_TYPE && TYPE_MODULAR_P (type_node))
2019 type = copy_node (type);
2020 TREE_TYPE (type) = type_node;
2022 else if (TREE_TYPE (type_node) != 0
2023 && TREE_CODE (TREE_TYPE (type_node)) == INTEGER_TYPE
2024 && TYPE_MODULAR_P (TREE_TYPE (type_node)))
2026 type = copy_node (type);
2027 TREE_TYPE (type) = TREE_TYPE (type_node);
2033 /* Return the signed version of a TYPE_NODE, a scalar type. */
2036 signed_type (type_node)
2039 tree type = type_for_size (TYPE_PRECISION (type_node), 0);
2041 if (TREE_CODE (type_node) == INTEGER_TYPE && TYPE_MODULAR_P (type_node))
2043 type = copy_node (type);
2044 TREE_TYPE (type) = type_node;
2046 else if (TREE_TYPE (type_node) != 0
2047 && TREE_CODE (TREE_TYPE (type_node)) == INTEGER_TYPE
2048 && TYPE_MODULAR_P (TREE_TYPE (type_node)))
2050 type = copy_node (type);
2051 TREE_TYPE (type) = TREE_TYPE (type_node);
2057 /* Return a type the same as TYPE except unsigned or signed according to
2061 signed_or_unsigned_type (unsignedp, type)
2065 if (! INTEGRAL_TYPE_P (type) || TREE_UNSIGNED (type) == unsignedp)
2068 return type_for_size (TYPE_PRECISION (type), unsignedp);
2071 /* EXP is an expression for the size of an object. If this size contains
2072 discriminant references, replace them with the maximum (if MAX_P) or
2073 minimum (if ! MAX_P) possible value of the discriminant. */
2076 max_size (exp, max_p)
2080 enum tree_code code = TREE_CODE (exp);
2081 tree type = TREE_TYPE (exp);
2083 switch (TREE_CODE_CLASS (code))
2090 if (code == TREE_LIST)
2091 return tree_cons (TREE_PURPOSE (exp),
2092 max_size (TREE_VALUE (exp), max_p),
2093 TREE_CHAIN (exp) != 0
2094 ? max_size (TREE_CHAIN (exp), max_p) : 0);
2098 /* If this contains a PLACEHOLDER_EXPR, it is the thing we want to
2099 modify. Otherwise, we abort since it is something we can't
2101 if (! contains_placeholder_p (exp))
2104 type = TREE_TYPE (TREE_OPERAND (exp, 1));
2106 max_size (max_p ? TYPE_MAX_VALUE (type) : TYPE_MIN_VALUE (type), 1);
2109 return max_p ? size_one_node : size_zero_node;
2114 switch (TREE_CODE_LENGTH (code))
2117 if (code == NON_LVALUE_EXPR)
2118 return max_size (TREE_OPERAND (exp, 0), max_p);
2121 fold (build1 (code, type,
2122 max_size (TREE_OPERAND (exp, 0),
2123 code == NEGATE_EXPR ? ! max_p : max_p)));
2126 if (code == RTL_EXPR)
2128 else if (code == COMPOUND_EXPR)
2129 return max_size (TREE_OPERAND (exp, 1), max_p);
2130 else if (code == WITH_RECORD_EXPR)
2134 tree lhs = max_size (TREE_OPERAND (exp, 0), max_p);
2135 tree rhs = max_size (TREE_OPERAND (exp, 1),
2136 code == MINUS_EXPR ? ! max_p : max_p);
2138 /* Special-case wanting the maximum value of a MIN_EXPR.
2139 In that case, if one side overflows, return the other.
2140 sizetype is signed, but we know sizes are non-negative.
2141 Likewise, handle a MINUS_EXPR or PLUS_EXPR with the LHS
2142 overflowing or the maximum possible value and the RHS
2144 if (max_p && code == MIN_EXPR && TREE_OVERFLOW (rhs))
2146 else if (max_p && code == MIN_EXPR && TREE_OVERFLOW (lhs))
2148 else if ((code == MINUS_EXPR || code == PLUS_EXPR)
2149 && (TREE_OVERFLOW (lhs)
2150 || operand_equal_p (lhs, TYPE_MAX_VALUE (type), 0))
2151 && ! TREE_CONSTANT (rhs))
2154 return fold (build (code, type, lhs, rhs));
2158 if (code == SAVE_EXPR)
2160 else if (code == COND_EXPR)
2161 return fold (build (MAX_EXPR, type,
2162 max_size (TREE_OPERAND (exp, 1), max_p),
2163 max_size (TREE_OPERAND (exp, 2), max_p)));
2164 else if (code == CALL_EXPR && TREE_OPERAND (exp, 1) != 0)
2165 return build (CALL_EXPR, type, TREE_OPERAND (exp, 0),
2166 max_size (TREE_OPERAND (exp, 1), max_p));
2173 /* Build a template of type TEMPLATE_TYPE from the array bounds of ARRAY_TYPE.
2174 EXPR is an expression that we can use to locate any PLACEHOLDER_EXPRs.
2175 Return a constructor for the template. */
2178 build_template (template_type, array_type, expr)
2183 tree template_elts = NULL_TREE;
2184 tree bound_list = NULL_TREE;
2187 if (TREE_CODE (array_type) == RECORD_TYPE
2188 && (TYPE_IS_PADDING_P (array_type)
2189 || TYPE_LEFT_JUSTIFIED_MODULAR_P (array_type)))
2190 array_type = TREE_TYPE (TYPE_FIELDS (array_type));
2192 if (TREE_CODE (array_type) == ARRAY_TYPE
2193 || (TREE_CODE (array_type) == INTEGER_TYPE
2194 && TYPE_HAS_ACTUAL_BOUNDS_P (array_type)))
2195 bound_list = TYPE_ACTUAL_BOUNDS (array_type);
2197 /* First make the list for a CONSTRUCTOR for the template. Go down the
2198 field list of the template instead of the type chain because this
2199 array might be an Ada array of arrays and we can't tell where the
2200 nested arrays stop being the underlying object. */
2202 for (field = TYPE_FIELDS (template_type); field;
2204 ? (bound_list = TREE_CHAIN (bound_list))
2205 : (array_type = TREE_TYPE (array_type))),
2206 field = TREE_CHAIN (TREE_CHAIN (field)))
2208 tree bounds, min, max;
2210 /* If we have a bound list, get the bounds from there. Likewise
2211 for an ARRAY_TYPE. Otherwise, if expr is a PARM_DECL with
2212 DECL_BY_COMPONENT_PTR_P, use the bounds of the field in the template.
2213 This will give us a maximum range. */
2214 if (bound_list != 0)
2215 bounds = TREE_VALUE (bound_list);
2216 else if (TREE_CODE (array_type) == ARRAY_TYPE)
2217 bounds = TYPE_INDEX_TYPE (TYPE_DOMAIN (array_type));
2218 else if (expr != 0 && TREE_CODE (expr) == PARM_DECL
2219 && DECL_BY_COMPONENT_PTR_P (expr))
2220 bounds = TREE_TYPE (field);
2224 min = convert (TREE_TYPE (TREE_CHAIN (field)), TYPE_MIN_VALUE (bounds));
2225 max = convert (TREE_TYPE (field), TYPE_MAX_VALUE (bounds));
2227 /* If either MIN or MAX involve a PLACEHOLDER_EXPR, we must
2228 surround them with a WITH_RECORD_EXPR giving EXPR as the
2230 if (! TREE_CONSTANT (min) && contains_placeholder_p (min))
2231 min = build (WITH_RECORD_EXPR, TREE_TYPE (min), min, expr);
2232 if (! TREE_CONSTANT (max) && contains_placeholder_p (max))
2233 max = build (WITH_RECORD_EXPR, TREE_TYPE (max), max, expr);
2235 template_elts = tree_cons (TREE_CHAIN (field), max,
2236 tree_cons (field, min, template_elts));
2239 return build_constructor (template_type, nreverse (template_elts));
2242 /* Build a VMS descriptor from a Mechanism_Type, which must specify
2243 a descriptor type, and the GCC type of an object. Each FIELD_DECL
2244 in the type contains in its DECL_INITIAL the expression to use when
2245 a constructor is made for the type. GNAT_ENTITY is a gnat node used
2246 to print out an error message if the mechanism cannot be applied to
2247 an object of that type and also for the name. */
2250 build_vms_descriptor (type, mech, gnat_entity)
2252 Mechanism_Type mech;
2253 Entity_Id gnat_entity;
2255 tree record_type = make_node (RECORD_TYPE);
2256 tree field_list = 0;
2265 /* If TYPE is an unconstrained array, use the underlying array type. */
2266 if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
2267 type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (type))));
2269 /* If this is an array, compute the number of dimensions in the array,
2270 get the index types, and point to the inner type. */
2271 if (TREE_CODE (type) != ARRAY_TYPE)
2274 for (ndim = 1, inner_type = type;
2275 TREE_CODE (TREE_TYPE (inner_type)) == ARRAY_TYPE
2276 && TYPE_MULTI_ARRAY_P (TREE_TYPE (inner_type));
2277 ndim++, inner_type = TREE_TYPE (inner_type))
2280 idx_arr = (tree *) alloca (ndim * sizeof (tree));
2282 if (mech != By_Descriptor_NCA
2283 && TREE_CODE (type) == ARRAY_TYPE && TYPE_CONVENTION_FORTRAN_P (type))
2284 for (i = ndim - 1, inner_type = type;
2286 i--, inner_type = TREE_TYPE (inner_type))
2287 idx_arr[i] = TYPE_DOMAIN (inner_type);
2289 for (i = 0, inner_type = type;
2291 i++, inner_type = TREE_TYPE (inner_type))
2292 idx_arr[i] = TYPE_DOMAIN (inner_type);
2294 /* Now get the DTYPE value. */
2295 switch (TREE_CODE (type))
2299 if (TYPE_VAX_FLOATING_POINT_P (type))
2300 switch ((int) TYPE_DIGITS_VALUE (type))
2313 switch (GET_MODE_BITSIZE (TYPE_MODE (type)))
2316 dtype = TREE_UNSIGNED (type) ? 2 : 6;
2319 dtype = TREE_UNSIGNED (type) ? 3 : 7;
2322 dtype = TREE_UNSIGNED (type) ? 4 : 8;
2325 dtype = TREE_UNSIGNED (type) ? 5 : 9;
2328 dtype = TREE_UNSIGNED (type) ? 25 : 26;
2334 dtype = GET_MODE_BITSIZE (TYPE_MODE (type)) == 32 ? 52 : 53;
2338 if (TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE
2339 && TYPE_VAX_FLOATING_POINT_P (type))
2340 switch ((int) TYPE_DIGITS_VALUE (type))
2352 dtype = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (type))) == 32 ? 54: 55;
2363 /* Get the CLASS value. */
2366 case By_Descriptor_A:
2369 case By_Descriptor_NCA:
2372 case By_Descriptor_SB:
2379 /* Make the type for a descriptor for VMS. The first four fields
2380 are the same for all types. */
2383 = chainon (field_list,
2384 make_descriptor_field
2385 ("LENGTH", type_for_size (16, 1), record_type,
2386 size_in_bytes (mech == By_Descriptor_A ? inner_type : type)));
2388 field_list = chainon (field_list,
2389 make_descriptor_field ("DTYPE", type_for_size (8, 1),
2390 record_type, size_int (dtype)));
2391 field_list = chainon (field_list,
2392 make_descriptor_field ("CLASS", type_for_size (8, 1),
2393 record_type, size_int (class)));
2396 = chainon (field_list,
2397 make_descriptor_field ("POINTER",
2398 build_pointer_type (type),
2401 build_pointer_type (type),
2402 build (PLACEHOLDER_EXPR,
2408 case By_Descriptor_S:
2411 case By_Descriptor_SB:
2413 = chainon (field_list,
2414 make_descriptor_field
2415 ("SB_L1", type_for_size (32, 1), record_type,
2416 TREE_CODE (type) == ARRAY_TYPE
2417 ? TYPE_MIN_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2419 = chainon (field_list,
2420 make_descriptor_field
2421 ("SB_L2", type_for_size (32, 1), record_type,
2422 TREE_CODE (type) == ARRAY_TYPE
2423 ? TYPE_MAX_VALUE (TYPE_DOMAIN (type)) : size_zero_node));
2426 case By_Descriptor_A:
2427 case By_Descriptor_NCA:
2428 field_list = chainon (field_list,
2429 make_descriptor_field ("SCALE",
2430 type_for_size (8, 1),
2434 field_list = chainon (field_list,
2435 make_descriptor_field ("DIGITS",
2436 type_for_size (8, 1),
2441 = chainon (field_list,
2442 make_descriptor_field
2443 ("AFLAGS", type_for_size (8, 1), record_type,
2444 size_int (mech == By_Descriptor_NCA
2446 /* Set FL_COLUMN, FL_COEFF, and FL_BOUNDS. */
2447 : (TREE_CODE (type) == ARRAY_TYPE
2448 && TYPE_CONVENTION_FORTRAN_P (type)
2451 field_list = chainon (field_list,
2452 make_descriptor_field ("DIMCT",
2453 type_for_size (8, 1),
2457 field_list = chainon (field_list,
2458 make_descriptor_field ("ARSIZE",
2459 type_for_size (32, 1),
2461 size_in_bytes (type)));
2463 /* Now build a pointer to the 0,0,0... element. */
2464 tem = build (PLACEHOLDER_EXPR, type);
2465 for (i = 0, inner_type = type; i < ndim;
2466 i++, inner_type = TREE_TYPE (inner_type))
2467 tem = build (ARRAY_REF, TREE_TYPE (inner_type), tem,
2468 convert (TYPE_DOMAIN (inner_type), size_zero_node));
2471 = chainon (field_list,
2472 make_descriptor_field
2473 ("A0", build_pointer_type (inner_type), record_type,
2474 build1 (ADDR_EXPR, build_pointer_type (inner_type), tem)));
2476 /* Next come the addressing coefficients. */
2478 for (i = 0; i < ndim; i++)
2482 = size_binop (MULT_EXPR, tem,
2483 size_binop (PLUS_EXPR,
2484 size_binop (MINUS_EXPR,
2485 TYPE_MAX_VALUE (idx_arr[i]),
2486 TYPE_MIN_VALUE (idx_arr[i])),
2489 fname[0] = (mech == By_Descriptor_NCA ? 'S' : 'M');
2490 fname[1] = '0' + i, fname[2] = 0;
2491 field_list = chainon (field_list,
2492 make_descriptor_field (fname,
2493 type_for_size (32, 1),
2497 if (mech == By_Descriptor_NCA)
2501 /* Finally here are the bounds. */
2502 for (i = 0; i < ndim; i++)
2506 fname[0] = 'L', fname[1] = '0' + i, fname[2] = 0;
2508 = chainon (field_list,
2509 make_descriptor_field
2510 (fname, type_for_size (32, 1), record_type,
2511 TYPE_MIN_VALUE (idx_arr[i])));
2515 = chainon (field_list,
2516 make_descriptor_field
2517 (fname, type_for_size (32, 1), record_type,
2518 TYPE_MAX_VALUE (idx_arr[i])));
2523 post_error ("unsupported descriptor type for &", gnat_entity);
2526 finish_record_type (record_type, field_list, 0, 1);
2527 pushdecl (build_decl (TYPE_DECL, create_concat_name (gnat_entity, "DESC"),
2533 /* Utility routine for above code to make a field. */
2536 make_descriptor_field (name, type, rec_type, initial)
2543 = create_field_decl (get_identifier (name), type, rec_type, 0, 0, 0, 0);
2545 DECL_INITIAL (field) = initial;
2549 /* Build a type to be used to represent an aliased object whose nominal
2550 type is an unconstrained array. This consists of a RECORD_TYPE containing
2551 a field of TEMPLATE_TYPE and a field of OBJECT_TYPE, which is an
2552 ARRAY_TYPE. If ARRAY_TYPE is that of the unconstrained array, this
2553 is used to represent an arbitrary unconstrained object. Use NAME
2554 as the name of the record. */
2557 build_unc_object_type (template_type, object_type, name)
2562 tree type = make_node (RECORD_TYPE);
2563 tree template_field = create_field_decl (get_identifier ("BOUNDS"),
2564 template_type, type, 0, 0, 0, 1);
2565 tree array_field = create_field_decl (get_identifier ("ARRAY"), object_type,
2568 TYPE_NAME (type) = name;
2569 TYPE_CONTAINS_TEMPLATE_P (type) = 1;
2570 finish_record_type (type,
2571 chainon (chainon (NULL_TREE, template_field),
2578 /* Update anything previously pointing to OLD_TYPE to point to NEW_TYPE. In
2579 the normal case this is just two adjustments, but we have more to do
2580 if NEW is an UNCONSTRAINED_ARRAY_TYPE. */
2583 update_pointer_to (old_type, new_type)
2587 tree ptr = TYPE_POINTER_TO (old_type);
2588 tree ref = TYPE_REFERENCE_TO (old_type);
2591 /* If this is the main variant, process all the other variants first. */
2592 if (TYPE_MAIN_VARIANT (old_type) == old_type)
2593 for (type = TYPE_NEXT_VARIANT (old_type); type != 0;
2594 type = TYPE_NEXT_VARIANT (type))
2595 update_pointer_to (type, new_type);
2597 /* If no pointer or reference, we are done. Otherwise, get the new type with
2598 the same qualifiers as the old type and see if it is the same as the old
2600 if (ptr == 0 && ref == 0)
2603 new_type = build_qualified_type (new_type, TYPE_QUALS (old_type));
2604 if (old_type == new_type)
2607 /* First handle the simple case. */
2608 if (TREE_CODE (new_type) != UNCONSTRAINED_ARRAY_TYPE)
2611 TREE_TYPE (ptr) = new_type;
2612 TYPE_POINTER_TO (new_type) = ptr;
2615 TREE_TYPE (ref) = new_type;
2616 TYPE_REFERENCE_TO (new_type) = ref;
2618 if (ptr != 0 && TYPE_NAME (ptr) != 0
2619 && TREE_CODE (TYPE_NAME (ptr)) == TYPE_DECL
2620 && TREE_CODE (new_type) != ENUMERAL_TYPE)
2621 rest_of_decl_compilation (TYPE_NAME (ptr), NULL,
2622 global_bindings_p (), 0);
2623 if (ref != 0 && TYPE_NAME (ref) != 0
2624 && TREE_CODE (TYPE_NAME (ref)) == TYPE_DECL
2625 && TREE_CODE (new_type) != ENUMERAL_TYPE)
2626 rest_of_decl_compilation (TYPE_NAME (ref), NULL,
2627 global_bindings_p (), 0);
2630 /* Now deal with the unconstrained array case. In this case the "pointer"
2631 is actually a RECORD_TYPE where the types of both fields are
2632 pointers to void. In that case, copy the field list from the
2633 old type to the new one and update the fields' context. */
2634 else if (TREE_CODE (ptr) != RECORD_TYPE || ! TYPE_IS_FAT_POINTER_P (ptr))
2639 tree new_obj_rec = TYPE_OBJECT_RECORD_TYPE (new_type);
2644 TYPE_FIELDS (ptr) = TYPE_FIELDS (TYPE_POINTER_TO (new_type));
2645 DECL_CONTEXT (TYPE_FIELDS (ptr)) = ptr;
2646 DECL_CONTEXT (TREE_CHAIN (TYPE_FIELDS (ptr))) = ptr;
2648 /* Rework the PLACEHOLDER_EXPR inside the reference to the
2651 ??? This is now the only use of gnat_substitute_in_type, which
2652 is now a very "heavy" routine to do this, so it should be replaced
2654 ptr_temp_type = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (ptr)));
2655 new_ref = build (COMPONENT_REF, ptr_temp_type,
2656 build (PLACEHOLDER_EXPR, ptr),
2657 TREE_CHAIN (TYPE_FIELDS (ptr)));
2660 (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (ptr))),
2661 gnat_substitute_in_type (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (ptr))),
2662 TREE_CHAIN (TYPE_FIELDS (ptr)), new_ref));
2664 for (var = TYPE_MAIN_VARIANT (ptr); var; var = TYPE_NEXT_VARIANT (var))
2665 TYPE_UNCONSTRAINED_ARRAY (var) = new_type;
2667 TYPE_POINTER_TO (new_type) = TYPE_REFERENCE_TO (new_type)
2668 = TREE_TYPE (new_type) = ptr;
2670 /* Now handle updating the allocation record, what the thin pointer
2671 points to. Update all pointers from the old record into the new
2672 one, update the types of the fields, and recompute the size. */
2674 update_pointer_to (TYPE_OBJECT_RECORD_TYPE (old_type), new_obj_rec);
2676 TREE_TYPE (TYPE_FIELDS (new_obj_rec)) = TREE_TYPE (ptr_temp_type);
2677 TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (new_obj_rec)))
2678 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (ptr)));
2679 DECL_SIZE (TREE_CHAIN (TYPE_FIELDS (new_obj_rec)))
2680 = TYPE_SIZE (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (ptr))));
2681 DECL_SIZE_UNIT (TREE_CHAIN (TYPE_FIELDS (new_obj_rec)))
2682 = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (TYPE_FIELDS (ptr))));
2684 TYPE_SIZE (new_obj_rec)
2685 = size_binop (PLUS_EXPR,
2686 DECL_SIZE (TYPE_FIELDS (new_obj_rec)),
2687 DECL_SIZE (TREE_CHAIN (TYPE_FIELDS (new_obj_rec))));
2688 TYPE_SIZE_UNIT (new_obj_rec)
2689 = size_binop (PLUS_EXPR,
2690 DECL_SIZE_UNIT (TYPE_FIELDS (new_obj_rec)),
2691 DECL_SIZE_UNIT (TREE_CHAIN (TYPE_FIELDS (new_obj_rec))));
2692 rest_of_type_compilation (ptr, global_bindings_p ());
2696 /* Convert a pointer to a constrained array into a pointer to a fat
2697 pointer. This involves making or finding a template. */
2700 convert_to_fat_pointer (type, expr)
2704 tree template_type = TREE_TYPE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (type))));
2705 tree template, template_addr;
2706 tree etype = TREE_TYPE (expr);
2708 /* If EXPR is a constant of zero, we make a fat pointer that has a null
2709 pointer to the template and array. */
2710 if (integer_zerop (expr))
2714 tree_cons (TYPE_FIELDS (type),
2715 convert (TREE_TYPE (TYPE_FIELDS (type)), expr),
2716 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
2717 convert (build_pointer_type (template_type),
2721 /* If EXPR is a thin pointer, make the template and data from the record. */
2723 else if (TYPE_THIN_POINTER_P (etype))
2725 tree fields = TYPE_FIELDS (TREE_TYPE (etype));
2727 expr = save_expr (expr);
2728 if (TREE_CODE (expr) == ADDR_EXPR)
2729 expr = TREE_OPERAND (expr, 0);
2731 expr = build1 (INDIRECT_REF, TREE_TYPE (etype), expr);
2733 template = build_component_ref (expr, NULL_TREE, fields);
2734 expr = build_unary_op (ADDR_EXPR, NULL_TREE,
2735 build_component_ref (expr, NULL_TREE,
2736 TREE_CHAIN (fields)));
2739 /* Otherwise, build the constructor for the template. */
2740 template = build_template (template_type, TREE_TYPE (etype), expr);
2742 template_addr = build_unary_op (ADDR_EXPR, NULL_TREE, template);
2744 /* The result is a CONSTRUCTOR for the fat pointer. */
2746 build_constructor (type,
2747 tree_cons (TYPE_FIELDS (type), expr,
2748 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
2749 template_addr, NULL_TREE)));
2752 /* Convert to a thin pointer type, TYPE. The only thing we know how to convert
2753 is something that is a fat pointer, so convert to it first if it EXPR
2754 is not already a fat pointer. */
2757 convert_to_thin_pointer (type, expr)
2761 if (! TYPE_FAT_POINTER_P (TREE_TYPE (expr)))
2763 = convert_to_fat_pointer
2764 (TREE_TYPE (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type))), expr);
2766 /* We get the pointer to the data and use a NOP_EXPR to make it the
2768 expr = build_component_ref (expr, NULL_TREE, TYPE_FIELDS (TREE_TYPE (expr)));
2769 expr = build1 (NOP_EXPR, type, expr);
2774 /* Create an expression whose value is that of EXPR,
2775 converted to type TYPE. The TREE_TYPE of the value
2776 is always TYPE. This function implements all reasonable
2777 conversions; callers should filter out those that are
2778 not permitted by the language being compiled. */
2781 convert (type, expr)
2784 enum tree_code code = TREE_CODE (type);
2785 tree etype = TREE_TYPE (expr);
2786 enum tree_code ecode = TREE_CODE (etype);
2789 /* If EXPR is already the right type, we are done. */
2793 /* If EXPR is a WITH_RECORD_EXPR, do the conversion inside and then make a
2795 if (TREE_CODE (expr) == WITH_RECORD_EXPR)
2796 return build (WITH_RECORD_EXPR, type,
2797 convert (type, TREE_OPERAND (expr, 0)),
2798 TREE_OPERAND (expr, 1));
2800 /* If the input type has padding, remove it by doing a component reference
2801 to the field. If the output type has padding, make a constructor
2802 to build the record. If both input and output have padding and are
2803 of variable size, do this as an unchecked conversion. */
2804 if (ecode == RECORD_TYPE && code == RECORD_TYPE
2805 && TYPE_IS_PADDING_P (type) && TYPE_IS_PADDING_P (etype)
2806 && (! TREE_CONSTANT (TYPE_SIZE (type))
2807 || ! TREE_CONSTANT (TYPE_SIZE (etype))))
2809 else if (ecode == RECORD_TYPE && TYPE_IS_PADDING_P (etype))
2811 /* If we have just converted to this padded type, just get
2812 the inner expression. */
2813 if (TREE_CODE (expr) == CONSTRUCTOR
2814 && CONSTRUCTOR_ELTS (expr) != 0
2815 && TREE_PURPOSE (CONSTRUCTOR_ELTS (expr)) == TYPE_FIELDS (etype))
2816 return TREE_VALUE (CONSTRUCTOR_ELTS (expr));
2818 return convert (type, build_component_ref (expr, NULL_TREE,
2819 TYPE_FIELDS (etype)));
2821 else if (code == RECORD_TYPE && TYPE_IS_PADDING_P (type))
2823 /* If we previously converted from another type and our type is
2824 of variable size, remove the conversion to avoid the need for
2825 variable-size temporaries. */
2826 if (TREE_CODE (expr) == UNCHECKED_CONVERT_EXPR
2827 && ! TREE_CONSTANT (TYPE_SIZE (type)))
2828 expr = TREE_OPERAND (expr, 0);
2830 /* If we are just removing the padding from expr, convert the original
2831 object if we have variable size. That will avoid the need
2832 for some variable-size temporaries. */
2833 if (TREE_CODE (expr) == COMPONENT_REF
2834 && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE
2835 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (expr, 0)))
2836 && ! TREE_CONSTANT (TYPE_SIZE (type)))
2837 return convert (type, TREE_OPERAND (expr, 0));
2839 /* If the result type is a padded type with a self-referentially-sized
2840 field and the expression type is a record, do this as an
2841 unchecked converstion. */
2842 else if (TREE_CODE (DECL_SIZE (TYPE_FIELDS (type))) != INTEGER_CST
2843 && contains_placeholder_p (DECL_SIZE (TYPE_FIELDS (type)))
2844 && TREE_CODE (etype) == RECORD_TYPE)
2845 return unchecked_convert (type, expr);
2849 build_constructor (type,
2850 tree_cons (TYPE_FIELDS (type),
2852 (TYPE_FIELDS (type)),
2857 /* If the input is a biased type, adjust first. */
2858 if (ecode == INTEGER_TYPE && TYPE_BIASED_REPRESENTATION_P (etype))
2859 return convert (type, fold (build (PLUS_EXPR, TREE_TYPE (etype),
2860 fold (build1 (GNAT_NOP_EXPR,
2861 TREE_TYPE (etype), expr)),
2862 TYPE_MIN_VALUE (etype))));
2864 /* If the input is a left-justified modular type, we need to extract
2865 the actual object before converting it to any other type with the
2866 exception of an unconstrained array. */
2867 if (ecode == RECORD_TYPE && TYPE_LEFT_JUSTIFIED_MODULAR_P (etype)
2868 && code != UNCONSTRAINED_ARRAY_TYPE)
2869 return convert (type, build_component_ref (expr, NULL_TREE,
2870 TYPE_FIELDS (etype)));
2872 /* If converting a type that does not contain a template into one
2873 that does, convert to the data type and then build the template. */
2874 if (code == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (type)
2875 && ! (ecode == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (etype)))
2877 tree obj_type = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (type)));
2882 tree_cons (TYPE_FIELDS (type),
2883 build_template (TREE_TYPE (TYPE_FIELDS (type)),
2884 obj_type, NULL_TREE),
2885 tree_cons (TREE_CHAIN (TYPE_FIELDS (type)),
2886 convert (obj_type, expr), NULL_TREE)));
2889 /* There are some special cases of expressions that we process
2891 switch (TREE_CODE (expr))
2896 case TRANSFORM_EXPR:
2898 /* Just set its type here. For TRANSFORM_EXPR, we will do the actual
2899 conversion in gnat_expand_expr. NULL_EXPR does not represent
2900 and actual value, so no conversion is needed. */
2901 TREE_TYPE (expr) = type;
2906 /* If we are converting a STRING_CST to another constrained array type,
2907 just make a new one in the proper type. Likewise for a
2908 CONSTRUCTOR. But if the mode of the type is different, we must
2909 ensure a new RTL is made for the constant. */
2910 if (code == ecode && AGGREGATE_TYPE_P (etype)
2911 && ! (TREE_CODE (TYPE_SIZE (etype)) == INTEGER_CST
2912 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
2914 expr = copy_node (expr);
2915 TREE_TYPE (expr) = type;
2917 if (TYPE_MODE (type) != TYPE_MODE (etype))
2918 TREE_CST_RTL (expr) = 0;
2925 /* If we are converting between two aggregate types of the same
2926 kind, size, mode, and alignment, just make a new COMPONENT_REF.
2927 This avoid unneeded conversions which makes reference computations
2929 if (code == ecode && TYPE_MODE (type) == TYPE_MODE (etype)
2930 && AGGREGATE_TYPE_P (type) && AGGREGATE_TYPE_P (etype)
2931 && TYPE_ALIGN (type) == TYPE_ALIGN (etype)
2932 && operand_equal_p (TYPE_SIZE (type), TYPE_SIZE (etype), 0))
2933 return build (COMPONENT_REF, type, TREE_OPERAND (expr, 0),
2934 TREE_OPERAND (expr, 1));
2938 case UNCONSTRAINED_ARRAY_REF:
2939 /* Convert this to the type of the inner array by getting the address of
2940 the array from the template. */
2941 expr = build_unary_op (INDIRECT_REF, NULL_TREE,
2942 build_component_ref (TREE_OPERAND (expr, 0),
2943 get_identifier ("P_ARRAY"),
2945 etype = TREE_TYPE (expr);
2946 ecode = TREE_CODE (etype);
2949 case UNCHECKED_CONVERT_EXPR:
2950 if (AGGREGATE_TYPE_P (type) && AGGREGATE_TYPE_P (etype)
2951 && ! TYPE_FAT_POINTER_P (type) && ! TYPE_FAT_POINTER_P (etype))
2952 return convert (type, TREE_OPERAND (expr, 0));
2956 /* If both types are record types, just convert the pointer and
2957 make a new INDIRECT_REF.
2959 ??? Disable this for now since it causes problems with the
2960 code in build_binary_op for MODIFY_EXPR which wants to
2961 strip off conversions. But that code really is a mess and
2962 we need to do this a much better way some time. */
2964 && (TREE_CODE (type) == RECORD_TYPE
2965 || TREE_CODE (type) == UNION_TYPE)
2966 && (TREE_CODE (etype) == RECORD_TYPE
2967 || TREE_CODE (etype) == UNION_TYPE)
2968 && ! TYPE_FAT_POINTER_P (type) && ! TYPE_FAT_POINTER_P (etype))
2969 return build_unary_op (INDIRECT_REF, NULL_TREE,
2970 convert (build_pointer_type (type),
2971 TREE_OPERAND (expr, 0)));
2978 /* Check for converting to a pointer to an unconstrained array. */
2979 if (TYPE_FAT_POINTER_P (type) && ! TYPE_FAT_POINTER_P (etype))
2980 return convert_to_fat_pointer (type, expr);
2982 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (etype)
2983 || (code == INTEGER_CST && ecode == INTEGER_CST
2984 && (type == TREE_TYPE (etype) || etype == TREE_TYPE (type))))
2985 return fold (build1 (NOP_EXPR, type, expr));
2990 return build1 (CONVERT_EXPR, type, expr);
2993 if (TYPE_HAS_ACTUAL_BOUNDS_P (type)
2994 && (ecode == ARRAY_TYPE || ecode == UNCONSTRAINED_ARRAY_TYPE))
2995 return unchecked_convert (type, expr);
2996 else if (TYPE_BIASED_REPRESENTATION_P (type))
2997 return fold (build1 (CONVERT_EXPR, type,
2998 fold (build (MINUS_EXPR, TREE_TYPE (type),
2999 convert (TREE_TYPE (type), expr),
3000 TYPE_MIN_VALUE (type)))));
3002 /* ... fall through ... */
3005 return fold (convert_to_integer (type, expr));
3008 case REFERENCE_TYPE:
3009 /* If converting between two pointers to records denoting
3010 both a template and type, adjust if needed to account
3011 for any differing offsets, since one might be negative. */
3012 if (TYPE_THIN_POINTER_P (etype) && TYPE_THIN_POINTER_P (type))
3015 = size_diffop (bit_position (TYPE_FIELDS (TREE_TYPE (etype))),
3016 bit_position (TYPE_FIELDS (TREE_TYPE (type))));
3017 tree byte_diff = size_binop (CEIL_DIV_EXPR, bit_diff,
3018 sbitsize_int (BITS_PER_UNIT));
3020 expr = build1 (NOP_EXPR, type, expr);
3021 TREE_CONSTANT (expr) = TREE_CONSTANT (TREE_OPERAND (expr, 0));
3022 if (integer_zerop (byte_diff))
3025 return build_binary_op (PLUS_EXPR, type, expr,
3026 fold (convert_to_pointer (type, byte_diff)));
3029 /* If converting to a thin pointer, handle specially. */
3030 if (TYPE_THIN_POINTER_P (type)
3031 && TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)) != 0)
3032 return convert_to_thin_pointer (type, expr);
3034 /* If converting fat pointer to normal pointer, get the pointer to the
3035 array and then convert it. */
3036 else if (TYPE_FAT_POINTER_P (etype))
3037 expr = build_component_ref (expr, get_identifier ("P_ARRAY"),
3040 return fold (convert_to_pointer (type, expr));
3043 return fold (convert_to_real (type, expr));
3046 if (TYPE_LEFT_JUSTIFIED_MODULAR_P (type) && ! AGGREGATE_TYPE_P (etype))
3049 (type, tree_cons (TYPE_FIELDS (type),
3050 convert (TREE_TYPE (TYPE_FIELDS (type)), expr),
3053 /* ... fall through ... */
3056 /* In these cases, assume the front-end has validated the conversion.
3057 If the conversion is valid, it will be a bit-wise conversion, so
3058 it can be viewed as an unchecked conversion. */
3059 return unchecked_convert (type, expr);
3062 /* Just validate that the type is indeed that of a field
3063 of the type. Then make the simple conversion. */
3064 for (tem = TYPE_FIELDS (type); tem; tem = TREE_CHAIN (tem))
3065 if (TREE_TYPE (tem) == etype)
3066 return build1 (CONVERT_EXPR, type, expr);
3070 case UNCONSTRAINED_ARRAY_TYPE:
3071 /* If EXPR is a constrained array, take its address, convert it to a
3072 fat pointer, and then dereference it. Likewise if EXPR is a
3073 record containing both a template and a constrained array.
3074 Note that a record representing a left justified modular type
3075 always represents a packed constrained array. */
3076 if (ecode == ARRAY_TYPE
3077 || (ecode == INTEGER_TYPE && TYPE_HAS_ACTUAL_BOUNDS_P (etype))
3078 || (ecode == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (etype))
3079 || (ecode == RECORD_TYPE && TYPE_LEFT_JUSTIFIED_MODULAR_P (etype)))
3082 (INDIRECT_REF, NULL_TREE,
3083 convert_to_fat_pointer (TREE_TYPE (type),
3084 build_unary_op (ADDR_EXPR,
3087 /* Do something very similar for converting one unconstrained
3088 array to another. */
3089 else if (ecode == UNCONSTRAINED_ARRAY_TYPE)
3091 build_unary_op (INDIRECT_REF, NULL_TREE,
3092 convert (TREE_TYPE (type),
3093 build_unary_op (ADDR_EXPR,
3099 return fold (convert_to_complex (type, expr));
3106 /* Remove all conversions that are done in EXP. This includes converting
3107 from a padded type or converting to a left-justified modular type. */
3110 remove_conversions (exp)
3113 switch (TREE_CODE (exp))
3116 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
3117 && TYPE_LEFT_JUSTIFIED_MODULAR_P (TREE_TYPE (exp)))
3118 return remove_conversions (TREE_VALUE (CONSTRUCTOR_ELTS (exp)));
3122 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == RECORD_TYPE
3123 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (exp, 0))))
3124 return remove_conversions (TREE_OPERAND (exp, 0));
3127 case UNCHECKED_CONVERT_EXPR:
3128 case NOP_EXPR: case CONVERT_EXPR:
3129 return remove_conversions (TREE_OPERAND (exp, 0));
3138 /* If EXP's type is an UNCONSTRAINED_ARRAY_TYPE, return an expression that
3139 refers to the underlying array. If its type has TYPE_CONTAINS_TEMPLATE_P,
3140 likewise return an expression pointing to the underlying array. */
3143 maybe_unconstrained_array (exp)
3146 enum tree_code code = TREE_CODE (exp);
3149 switch (TREE_CODE (TREE_TYPE (exp)))
3151 case UNCONSTRAINED_ARRAY_TYPE:
3152 if (code == UNCONSTRAINED_ARRAY_REF)
3155 = build_unary_op (INDIRECT_REF, NULL_TREE,
3156 build_component_ref (TREE_OPERAND (exp, 0),
3157 get_identifier ("P_ARRAY"),
3159 TREE_READONLY (new) = TREE_STATIC (new) = TREE_READONLY (exp);
3163 else if (code == NULL_EXPR)
3164 return build1 (NULL_EXPR,
3165 TREE_TYPE (TREE_TYPE (TYPE_FIELDS
3166 (TREE_TYPE (TREE_TYPE (exp))))),
3167 TREE_OPERAND (exp, 0));
3169 else if (code == WITH_RECORD_EXPR
3170 && (TREE_OPERAND (exp, 0)
3171 != (new = maybe_unconstrained_array
3172 (TREE_OPERAND (exp, 0)))))
3173 return build (WITH_RECORD_EXPR, TREE_TYPE (new), new,
3174 TREE_OPERAND (exp, 1));
3177 if (TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (exp)))
3180 = build_component_ref (exp, NULL_TREE,
3181 TREE_CHAIN (TYPE_FIELDS (TREE_TYPE (exp))));
3182 if (TREE_CODE (TREE_TYPE (new)) == RECORD_TYPE
3183 && TYPE_IS_PADDING_P (TREE_TYPE (new)))
3184 new = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (new))), new);
3197 /* Return an expression that does an unchecked converstion of EXPR to TYPE. */
3200 unchecked_convert (type, expr)
3204 tree etype = TREE_TYPE (expr);
3206 /* If the expression is already the right type, we are done. */
3210 /* If EXPR is a WITH_RECORD_EXPR, do the conversion inside and then make a
3212 if (TREE_CODE (expr) == WITH_RECORD_EXPR)
3213 return build (WITH_RECORD_EXPR, type,
3214 unchecked_convert (type, TREE_OPERAND (expr, 0)),
3215 TREE_OPERAND (expr, 1));
3217 /* If both types types are integral just do a normal conversion.
3218 Likewise for a conversion to an unconstrained array. */
3219 if ((((INTEGRAL_TYPE_P (type)
3220 && ! (TREE_CODE (type) == INTEGER_TYPE
3221 && TYPE_VAX_FLOATING_POINT_P (type)))
3222 || (POINTER_TYPE_P (type) && ! TYPE_THIN_POINTER_P (type))
3223 || (TREE_CODE (type) == RECORD_TYPE
3224 && TYPE_LEFT_JUSTIFIED_MODULAR_P (type)))
3225 && ((INTEGRAL_TYPE_P (etype)
3226 && ! (TREE_CODE (etype) == INTEGER_TYPE
3227 && TYPE_VAX_FLOATING_POINT_P (etype)))
3228 || (POINTER_TYPE_P (etype) && ! TYPE_THIN_POINTER_P (etype))
3229 || (TREE_CODE (etype) == RECORD_TYPE
3230 && TYPE_LEFT_JUSTIFIED_MODULAR_P (etype))))
3231 || TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
3235 if (TREE_CODE (etype) == INTEGER_TYPE
3236 && TYPE_BIASED_REPRESENTATION_P (etype))
3238 tree ntype = copy_type (etype);
3240 TYPE_BIASED_REPRESENTATION_P (ntype) = 0;
3241 TYPE_MAIN_VARIANT (ntype) = ntype;
3242 expr = build1 (GNAT_NOP_EXPR, ntype, expr);
3245 if (TREE_CODE (type) == INTEGER_TYPE
3246 && TYPE_BIASED_REPRESENTATION_P (type))
3248 rtype = copy_type (type);
3249 TYPE_BIASED_REPRESENTATION_P (rtype) = 0;
3250 TYPE_MAIN_VARIANT (rtype) = rtype;
3253 expr = convert (rtype, expr);
3255 expr = build1 (GNAT_NOP_EXPR, type, expr);
3258 /* If we are converting TO an integral type whose precision is not the
3259 same as its size, first unchecked convert to a record that contains
3260 an object of the output type. Then extract the field. */
3261 else if (INTEGRAL_TYPE_P (type) && TYPE_RM_SIZE (type) != 0
3262 && 0 != compare_tree_int (TYPE_RM_SIZE (type),
3263 GET_MODE_BITSIZE (TYPE_MODE (type))))
3265 tree rec_type = make_node (RECORD_TYPE);
3266 tree field = create_field_decl (get_identifier ("OBJ"), type,
3267 rec_type, 1, 0, 0, 0);
3269 TYPE_FIELDS (rec_type) = field;
3270 layout_type (rec_type);
3272 expr = unchecked_convert (rec_type, expr);
3273 expr = build_component_ref (expr, NULL_TREE, field);
3276 /* Similarly for integral input type whose precision is not equal to its
3278 else if (INTEGRAL_TYPE_P (etype) && TYPE_RM_SIZE (etype) != 0
3279 && 0 != compare_tree_int (TYPE_RM_SIZE (etype),
3280 GET_MODE_BITSIZE (TYPE_MODE (etype))))
3282 tree rec_type = make_node (RECORD_TYPE);
3284 = create_field_decl (get_identifier ("OBJ"), etype, rec_type,
3287 TYPE_FIELDS (rec_type) = field;
3288 layout_type (rec_type);
3290 expr = build_constructor (rec_type, build_tree_list (field, expr));
3291 expr = unchecked_convert (type, expr);
3294 /* We have a special case when we are converting between two
3295 unconstrained array types. In that case, take the address,
3296 convert the fat pointer types, and dereference. */
3297 else if (TREE_CODE (etype) == UNCONSTRAINED_ARRAY_TYPE
3298 && TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
3299 expr = build_unary_op (INDIRECT_REF, NULL_TREE,
3300 build1 (UNCHECKED_CONVERT_EXPR, TREE_TYPE (type),
3301 build_unary_op (ADDR_EXPR, NULL_TREE,
3304 /* If both types are aggregates with the same mode and alignment (except
3305 if the result is a UNION_TYPE), we can do this as a normal conversion. */
3306 else if (AGGREGATE_TYPE_P (type) && AGGREGATE_TYPE_P (etype)
3307 && TREE_CODE (type) != UNION_TYPE
3308 && TYPE_ALIGN (type) == TYPE_ALIGN (etype)
3309 && TYPE_MODE (type) == TYPE_MODE (etype))
3310 expr = build1 (CONVERT_EXPR, type, expr);
3314 expr = maybe_unconstrained_array (expr);
3315 etype = TREE_TYPE (expr);
3316 expr = build1 (UNCHECKED_CONVERT_EXPR, type, expr);
3320 /* If the result is an integral type whose size is not equal to
3321 the size of the underlying machine type, sign- or zero-extend
3322 the result. We need not do this in the case where the input is
3323 an integral type of the same precision and signedness or if the output
3324 is a biased type or if both the input and output are unsigned. */
3325 if (INTEGRAL_TYPE_P (type) && TYPE_RM_SIZE (type) != 0
3326 && ! (TREE_CODE (type) == INTEGER_TYPE
3327 && TYPE_BIASED_REPRESENTATION_P (type))
3328 && 0 != compare_tree_int (TYPE_RM_SIZE (type),
3329 GET_MODE_BITSIZE (TYPE_MODE (type)))
3330 && ! (INTEGRAL_TYPE_P (etype)
3331 && TREE_UNSIGNED (type) == TREE_UNSIGNED (etype)
3332 && operand_equal_p (TYPE_RM_SIZE (type),
3333 (TYPE_RM_SIZE (etype) != 0
3334 ? TYPE_RM_SIZE (etype) : TYPE_SIZE (etype)),
3336 && ! (TREE_UNSIGNED (type) && TREE_UNSIGNED (etype)))
3338 tree base_type = type_for_mode (TYPE_MODE (type), TREE_UNSIGNED (type));
3340 = convert (base_type,
3341 size_binop (MINUS_EXPR,
3343 (GET_MODE_BITSIZE (TYPE_MODE (type))),
3344 TYPE_RM_SIZE (type)));
3347 build_binary_op (RSHIFT_EXPR, base_type,
3348 build_binary_op (LSHIFT_EXPR, base_type,
3349 convert (base_type, expr),
3354 /* An unchecked conversion should never raise Constraint_Error. The code
3355 below assumes that GCC's conversion routines overflow the same
3356 way that the underlying hardware does. This is probably true. In
3357 the rare case when it isn't, we can rely on the fact that such
3358 conversions are erroneous anyway. */
3359 if (TREE_CODE (expr) == INTEGER_CST)
3360 TREE_OVERFLOW (expr) = TREE_CONSTANT_OVERFLOW (expr) = 0;
3362 /* If the sizes of the types differ and this is an UNCHECKED_CONVERT_EXPR,
3363 show no longer constant. */
3364 if (TREE_CODE (expr) == UNCHECKED_CONVERT_EXPR
3365 && ! operand_equal_p (TYPE_SIZE_UNIT (type), TYPE_SIZE_UNIT (etype), 1))
3366 TREE_CONSTANT (expr) = 0;