1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 1992-2009, Free Software Foundation, Inc. *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 3, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License along with GCC; see the file COPYING3. If not see *
19 * <http://www.gnu.org/licenses/>. *
21 * GNAT was originally developed by the GNAT team at New York University. *
22 * Extensive contributions were provided by Ada Core Technologies Inc. *
24 ****************************************************************************/
28 #include "coretypes.h"
56 #ifndef MAX_FIXED_MODE_SIZE
57 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
60 /* Convention_Stdcall should be processed in a specific way on Windows targets
61 only. The macro below is a helper to avoid having to check for a Windows
62 specific attribute throughout this unit. */
64 #if TARGET_DLLIMPORT_DECL_ATTRIBUTES
65 #define Has_Stdcall_Convention(E) (Convention (E) == Convention_Stdcall)
67 #define Has_Stdcall_Convention(E) (0)
70 /* Stack realignment for functions with foreign conventions is provided on a
71 per back-end basis now, as it is handled by the prologue expanders and not
72 as part of the function's body any more. It might be requested by way of a
73 dedicated function type attribute on the targets that support it.
75 We need a way to avoid setting the attribute on the targets that don't
76 support it and use FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN for this purpose.
78 It is defined on targets where the circuitry is available, and indicates
79 whether the realignment is needed for 'main'. We use this to decide for
80 foreign subprograms as well.
82 It is not defined on targets where the circuitry is not implemented, and
83 we just never set the attribute in these cases.
85 Whether it is defined on all targets that would need it in theory is
86 not entirely clear. We currently trust the base GCC settings for this
89 #ifndef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
90 #define FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN 0
95 struct incomplete *next;
100 /* These variables are used to defer recursively expanding incomplete types
101 while we are processing an array, a record or a subprogram type. */
102 static int defer_incomplete_level = 0;
103 static struct incomplete *defer_incomplete_list;
105 /* This variable is used to delay expanding From_With_Type types until the
107 static struct incomplete *defer_limited_with;
109 /* These variables are used to defer finalizing types. The element of the
110 list is the TYPE_DECL associated with the type. */
111 static int defer_finalize_level = 0;
112 static VEC (tree,heap) *defer_finalize_list;
114 /* A hash table used to cache the result of annotate_value. */
115 static GTY ((if_marked ("tree_int_map_marked_p"),
116 param_is (struct tree_int_map))) htab_t annotate_value_cache;
125 static void relate_alias_sets (tree, tree, enum alias_set_op);
127 static tree substitution_list (Entity_Id, Entity_Id, tree, bool);
128 static bool allocatable_size_p (tree, bool);
129 static void prepend_one_attribute_to (struct attrib **,
130 enum attr_type, tree, tree, Node_Id);
131 static void prepend_attributes (Entity_Id, struct attrib **);
132 static tree elaborate_expression (Node_Id, Entity_Id, tree, bool, bool, bool);
133 static bool is_variable_size (tree);
134 static tree elaborate_expression_1 (Node_Id, Entity_Id, tree, tree,
136 static tree make_packable_type (tree, bool);
137 static tree gnat_to_gnu_field (Entity_Id, tree, int, bool);
138 static tree gnat_to_gnu_param (Entity_Id, Mechanism_Type, Entity_Id, bool,
140 static bool same_discriminant_p (Entity_Id, Entity_Id);
141 static bool array_type_has_nonaliased_component (Entity_Id, tree);
142 static bool compile_time_known_address_p (Node_Id);
143 static void components_to_record (tree, Node_Id, tree, int, bool, tree *,
144 bool, bool, bool, bool);
145 static Uint annotate_value (tree);
146 static void annotate_rep (Entity_Id, tree);
147 static tree compute_field_positions (tree, tree, tree, tree, unsigned int);
148 static tree validate_size (Uint, tree, Entity_Id, enum tree_code, bool, bool);
149 static void set_rm_size (Uint, tree, Entity_Id);
150 static tree make_type_from_size (tree, tree, bool);
151 static unsigned int validate_alignment (Uint, Entity_Id, unsigned int);
152 static unsigned int ceil_alignment (unsigned HOST_WIDE_INT);
153 static void check_ok_for_atomic (tree, Entity_Id, bool);
154 static int compatible_signatures_p (tree ftype1, tree ftype2);
155 static void rest_of_type_decl_compilation_no_defer (tree);
157 /* Given GNAT_ENTITY, a GNAT defining identifier node, which denotes some Ada
158 entity, return the equivalent GCC tree for that entity (a ..._DECL node)
159 and associate the ..._DECL node with the input GNAT defining identifier.
161 If GNAT_ENTITY is a variable or a constant declaration, GNU_EXPR gives its
162 initial value (in GCC tree form). This is optional for a variable. For
163 a renamed entity, GNU_EXPR gives the object being renamed.
165 DEFINITION is nonzero if this call is intended for a definition. This is
166 used for separate compilation where it is necessary to know whether an
167 external declaration or a definition must be created if the GCC equivalent
168 was not created previously. The value of 1 is normally used for a nonzero
169 DEFINITION, but a value of 2 is used in special circumstances, defined in
173 gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition)
175 Entity_Id gnat_equiv_type = Gigi_Equivalent_Type (gnat_entity);
177 Entity_Kind kind = Ekind (gnat_entity);
178 /* Contains the GCC DECL node which is equivalent to the input GNAT node.
179 This node will be associated with the GNAT node by calling at the end
180 of the `switch' statement. */
181 tree gnu_decl = NULL_TREE;
182 /* Contains the GCC type to be used for the GCC node. */
183 tree gnu_type = NULL_TREE;
184 /* Contains the GCC size tree to be used for the GCC node. */
185 tree gnu_size = NULL_TREE;
186 /* Contains the GCC name to be used for the GCC node. */
188 /* True if we have already saved gnu_decl as a GNAT association. */
190 /* True if we incremented defer_incomplete_level. */
191 bool this_deferred = false;
192 /* True if we incremented force_global. */
193 bool this_global = false;
194 /* True if we should check to see if elaborated during processing. */
195 bool maybe_present = false;
196 /* True if we made GNU_DECL and its type here. */
197 bool this_made_decl = false;
198 /* True if debug info is requested for this entity. */
199 bool debug_info_p = (Needs_Debug_Info (gnat_entity)
200 || debug_info_level == DINFO_LEVEL_VERBOSE);
201 /* True if this entity is to be considered as imported. */
202 bool imported_p = (Is_Imported (gnat_entity)
203 && No (Address_Clause (gnat_entity)));
205 = ((Known_Esize (gnat_entity)
206 && UI_Is_In_Int_Range (Esize (gnat_entity)))
207 ? MIN (UI_To_Int (Esize (gnat_entity)),
208 IN (kind, Float_Kind)
209 ? fp_prec_to_size (LONG_DOUBLE_TYPE_SIZE)
210 : IN (kind, Access_Kind) ? POINTER_SIZE * 2
211 : LONG_LONG_TYPE_SIZE)
212 : LONG_LONG_TYPE_SIZE);
213 unsigned int align = 0;
214 struct attrib *attr_list = NULL;
216 /* Since a use of an Itype is a definition, process it as such if it
217 is not in a with'ed unit. */
219 && Is_Itype (gnat_entity)
220 && !present_gnu_tree (gnat_entity)
221 && In_Extended_Main_Code_Unit (gnat_entity))
223 /* Ensure that we are in a subprogram mentioned in the Scope chain of
224 this entity, our current scope is global, or we encountered a task
225 or entry (where we can't currently accurately check scoping). */
226 if (!current_function_decl
227 || DECL_ELABORATION_PROC_P (current_function_decl))
229 process_type (gnat_entity);
230 return get_gnu_tree (gnat_entity);
233 for (gnat_temp = Scope (gnat_entity);
235 gnat_temp = Scope (gnat_temp))
237 if (Is_Type (gnat_temp))
238 gnat_temp = Underlying_Type (gnat_temp);
240 if (Ekind (gnat_temp) == E_Subprogram_Body)
242 = Corresponding_Spec (Parent (Declaration_Node (gnat_temp)));
244 if (IN (Ekind (gnat_temp), Subprogram_Kind)
245 && Present (Protected_Body_Subprogram (gnat_temp)))
246 gnat_temp = Protected_Body_Subprogram (gnat_temp);
248 if (Ekind (gnat_temp) == E_Entry
249 || Ekind (gnat_temp) == E_Entry_Family
250 || Ekind (gnat_temp) == E_Task_Type
251 || (IN (Ekind (gnat_temp), Subprogram_Kind)
252 && present_gnu_tree (gnat_temp)
253 && (current_function_decl
254 == gnat_to_gnu_entity (gnat_temp, NULL_TREE, 0))))
256 process_type (gnat_entity);
257 return get_gnu_tree (gnat_entity);
261 /* This abort means the entity has an incorrect scope, i.e. that its
262 scope does not correspond to the subprogram it is declared in. */
266 /* If the entiy is not present, something went badly wrong. */
267 gcc_assert (Present (gnat_entity));
269 /* If we've already processed this entity, return what we got last time.
270 If we are defining the node, we should not have already processed it.
271 In that case, we will abort below when we try to save a new GCC tree
272 for this object. We also need to handle the case of getting a dummy
273 type when a Full_View exists. */
274 if (present_gnu_tree (gnat_entity)
275 && (!definition || (Is_Type (gnat_entity) && imported_p)))
277 gnu_decl = get_gnu_tree (gnat_entity);
279 if (TREE_CODE (gnu_decl) == TYPE_DECL
280 && TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl))
281 && IN (kind, Incomplete_Or_Private_Kind)
282 && Present (Full_View (gnat_entity)))
285 = gnat_to_gnu_entity (Full_View (gnat_entity), NULL_TREE, 0);
286 save_gnu_tree (gnat_entity, NULL_TREE, false);
287 save_gnu_tree (gnat_entity, gnu_decl, false);
293 /* If this is a numeric or enumeral type, or an access type, a nonzero
294 Esize must be specified unless it was specified by the programmer. */
295 gcc_assert (!Unknown_Esize (gnat_entity)
296 || Has_Size_Clause (gnat_entity)
297 || (!IN (kind, Numeric_Kind)
298 && !IN (kind, Enumeration_Kind)
299 && (!IN (kind, Access_Kind)
300 || kind == E_Access_Protected_Subprogram_Type
301 || kind == E_Anonymous_Access_Protected_Subprogram_Type
302 || kind == E_Access_Subtype)));
304 /* RM_Size must be specified for all discrete and fixed-point types. */
305 gcc_assert (!IN (kind, Discrete_Or_Fixed_Point_Kind)
306 || !Unknown_RM_Size (gnat_entity));
308 /* Get the name of the entity and set up the line number and filename of
309 the original definition for use in any decl we make. */
310 gnu_entity_id = get_entity_name (gnat_entity);
311 Sloc_to_locus (Sloc (gnat_entity), &input_location);
313 /* If we get here, it means we have not yet done anything with this
314 entity. If we are not defining it here, it must be external,
315 otherwise we should have defined it already. */
316 gcc_assert (definition || Is_Public (gnat_entity) || type_annotate_only
317 || kind == E_Discriminant || kind == E_Component
319 || (kind == E_Constant && Present (Full_View (gnat_entity)))
320 || IN (kind, Type_Kind));
322 /* For cases when we are not defining (i.e., we are referencing from
323 another compilation unit) public entities, show we are at global level
324 for the purpose of computing scopes. Don't do this for components or
325 discriminants since the relevant test is whether or not the record is
326 being defined. But do this for Imported functions or procedures in
328 if ((!definition && Is_Public (gnat_entity)
329 && !Is_Statically_Allocated (gnat_entity)
330 && kind != E_Discriminant && kind != E_Component)
331 || (Is_Imported (gnat_entity)
332 && (kind == E_Function || kind == E_Procedure)))
333 force_global++, this_global = true;
335 /* Handle any attributes directly attached to the entity. */
336 if (Has_Gigi_Rep_Item (gnat_entity))
337 prepend_attributes (gnat_entity, &attr_list);
339 /* Machine_Attributes on types are expected to be propagated to subtypes.
340 The corresponding Gigi_Rep_Items are only attached to the first subtype
341 though, so we handle the propagation here. */
342 if (Is_Type (gnat_entity) && Base_Type (gnat_entity) != gnat_entity
343 && !Is_First_Subtype (gnat_entity)
344 && Has_Gigi_Rep_Item (First_Subtype (Base_Type (gnat_entity))))
345 prepend_attributes (First_Subtype (Base_Type (gnat_entity)), &attr_list);
350 /* If this is a use of a deferred constant without address clause,
351 get its full definition. */
353 && No (Address_Clause (gnat_entity))
354 && Present (Full_View (gnat_entity)))
357 = gnat_to_gnu_entity (Full_View (gnat_entity), gnu_expr, 0);
362 /* If we have an external constant that we are not defining, get the
363 expression that is was defined to represent. We may throw that
364 expression away later if it is not a constant. Do not retrieve the
365 expression if it is an aggregate or allocator, because in complex
366 instantiation contexts it may not be expanded */
368 && Present (Expression (Declaration_Node (gnat_entity)))
369 && !No_Initialization (Declaration_Node (gnat_entity))
370 && (Nkind (Expression (Declaration_Node (gnat_entity)))
372 && (Nkind (Expression (Declaration_Node (gnat_entity)))
374 gnu_expr = gnat_to_gnu (Expression (Declaration_Node (gnat_entity)));
376 /* Ignore deferred constant definitions without address clause since
377 they are processed fully in the front-end. If No_Initialization
378 is set, this is not a deferred constant but a constant whose value
379 is built manually. And constants that are renamings are handled
383 && No (Address_Clause (gnat_entity))
384 && !No_Initialization (Declaration_Node (gnat_entity))
385 && No (Renamed_Object (gnat_entity)))
387 gnu_decl = error_mark_node;
392 /* Ignore constant definitions already marked with the error node. See
393 the N_Object_Declaration case of gnat_to_gnu for the rationale. */
396 && present_gnu_tree (gnat_entity)
397 && get_gnu_tree (gnat_entity) == error_mark_node)
399 maybe_present = true;
406 /* We used to special case VMS exceptions here to directly map them to
407 their associated condition code. Since this code had to be masked
408 dynamically to strip off the severity bits, this caused trouble in
409 the GCC/ZCX case because the "type" pointers we store in the tables
410 have to be static. We now don't special case here anymore, and let
411 the regular processing take place, which leaves us with a regular
412 exception data object for VMS exceptions too. The condition code
413 mapping is taken care of by the front end and the bitmasking by the
420 /* The GNAT record where the component was defined. */
421 Entity_Id gnat_record = Underlying_Type (Scope (gnat_entity));
423 /* If the variable is an inherited record component (in the case of
424 extended record types), just return the inherited entity, which
425 must be a FIELD_DECL. Likewise for discriminants.
426 For discriminants of untagged records which have explicit
427 stored discriminants, return the entity for the corresponding
428 stored discriminant. Also use Original_Record_Component
429 if the record has a private extension. */
430 if (Present (Original_Record_Component (gnat_entity))
431 && Original_Record_Component (gnat_entity) != gnat_entity)
434 = gnat_to_gnu_entity (Original_Record_Component (gnat_entity),
435 gnu_expr, definition);
440 /* If the enclosing record has explicit stored discriminants,
441 then it is an untagged record. If the Corresponding_Discriminant
442 is not empty then this must be a renamed discriminant and its
443 Original_Record_Component must point to the corresponding explicit
444 stored discriminant (i.e. we should have taken the previous
446 else if (Present (Corresponding_Discriminant (gnat_entity))
447 && Is_Tagged_Type (gnat_record))
449 /* A tagged record has no explicit stored discriminants. */
450 gcc_assert (First_Discriminant (gnat_record)
451 == First_Stored_Discriminant (gnat_record));
453 = gnat_to_gnu_entity (Corresponding_Discriminant (gnat_entity),
454 gnu_expr, definition);
459 else if (Present (CR_Discriminant (gnat_entity))
460 && type_annotate_only)
462 gnu_decl = gnat_to_gnu_entity (CR_Discriminant (gnat_entity),
463 gnu_expr, definition);
468 /* If the enclosing record has explicit stored discriminants, then
469 it is an untagged record. If the Corresponding_Discriminant
470 is not empty then this must be a renamed discriminant and its
471 Original_Record_Component must point to the corresponding explicit
472 stored discriminant (i.e. we should have taken the first
474 else if (Present (Corresponding_Discriminant (gnat_entity))
475 && (First_Discriminant (gnat_record)
476 != First_Stored_Discriminant (gnat_record)))
479 /* Otherwise, if we are not defining this and we have no GCC type
480 for the containing record, make one for it. Then we should
481 have made our own equivalent. */
482 else if (!definition && !present_gnu_tree (gnat_record))
484 /* ??? If this is in a record whose scope is a protected
485 type and we have an Original_Record_Component, use it.
486 This is a workaround for major problems in protected type
488 Entity_Id Scop = Scope (Scope (gnat_entity));
489 if ((Is_Protected_Type (Scop)
490 || (Is_Private_Type (Scop)
491 && Present (Full_View (Scop))
492 && Is_Protected_Type (Full_View (Scop))))
493 && Present (Original_Record_Component (gnat_entity)))
496 = gnat_to_gnu_entity (Original_Record_Component
503 gnat_to_gnu_entity (Scope (gnat_entity), NULL_TREE, 0);
504 gnu_decl = get_gnu_tree (gnat_entity);
510 /* Here we have no GCC type and this is a reference rather than a
511 definition. This should never happen. Most likely the cause is
512 reference before declaration in the gnat tree for gnat_entity. */
516 case E_Loop_Parameter:
517 case E_Out_Parameter:
520 /* Simple variables, loop variables, Out parameters, and exceptions. */
523 bool used_by_ref = false;
525 = ((kind == E_Constant || kind == E_Variable)
526 && Is_True_Constant (gnat_entity)
527 && !Treat_As_Volatile (gnat_entity)
528 && (((Nkind (Declaration_Node (gnat_entity))
529 == N_Object_Declaration)
530 && Present (Expression (Declaration_Node (gnat_entity))))
531 || Present (Renamed_Object (gnat_entity))));
532 bool inner_const_flag = const_flag;
533 bool static_p = Is_Statically_Allocated (gnat_entity);
534 bool mutable_p = false;
535 tree gnu_ext_name = NULL_TREE;
536 tree renamed_obj = NULL_TREE;
537 tree gnu_object_size;
539 if (Present (Renamed_Object (gnat_entity)) && !definition)
541 if (kind == E_Exception)
542 gnu_expr = gnat_to_gnu_entity (Renamed_Entity (gnat_entity),
545 gnu_expr = gnat_to_gnu (Renamed_Object (gnat_entity));
548 /* Get the type after elaborating the renamed object. */
549 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
551 /* For a debug renaming declaration, build a pure debug entity. */
552 if (Present (Debug_Renaming_Link (gnat_entity)))
555 gnu_decl = build_decl (VAR_DECL, gnu_entity_id, gnu_type);
556 /* The (MEM (CONST (0))) pattern is prescribed by STABS. */
557 if (global_bindings_p ())
558 addr = gen_rtx_CONST (VOIDmode, const0_rtx);
560 addr = stack_pointer_rtx;
561 SET_DECL_RTL (gnu_decl, gen_rtx_MEM (Pmode, addr));
562 gnat_pushdecl (gnu_decl, gnat_entity);
566 /* If this is a loop variable, its type should be the base type.
567 This is because the code for processing a loop determines whether
568 a normal loop end test can be done by comparing the bounds of the
569 loop against those of the base type, which is presumed to be the
570 size used for computation. But this is not correct when the size
571 of the subtype is smaller than the type. */
572 if (kind == E_Loop_Parameter)
573 gnu_type = get_base_type (gnu_type);
575 /* Reject non-renamed objects whose types are unconstrained arrays or
576 any object whose type is a dummy type or VOID_TYPE. */
578 if ((TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
579 && No (Renamed_Object (gnat_entity)))
580 || TYPE_IS_DUMMY_P (gnu_type)
581 || TREE_CODE (gnu_type) == VOID_TYPE)
583 gcc_assert (type_annotate_only);
586 return error_mark_node;
589 /* If an alignment is specified, use it if valid. Note that
590 exceptions are objects but don't have alignments. We must do this
591 before we validate the size, since the alignment can affect the
593 if (kind != E_Exception && Known_Alignment (gnat_entity))
595 gcc_assert (Present (Alignment (gnat_entity)));
596 align = validate_alignment (Alignment (gnat_entity), gnat_entity,
597 TYPE_ALIGN (gnu_type));
598 gnu_type = maybe_pad_type (gnu_type, NULL_TREE, align, gnat_entity,
599 "PAD", false, definition, true);
602 /* If we are defining the object, see if it has a Size value and
603 validate it if so. If we are not defining the object and a Size
604 clause applies, simply retrieve the value. We don't want to ignore
605 the clause and it is expected to have been validated already. Then
606 get the new type, if any. */
608 gnu_size = validate_size (Esize (gnat_entity), gnu_type,
609 gnat_entity, VAR_DECL, false,
610 Has_Size_Clause (gnat_entity));
611 else if (Has_Size_Clause (gnat_entity))
612 gnu_size = UI_To_gnu (Esize (gnat_entity), bitsizetype);
617 = make_type_from_size (gnu_type, gnu_size,
618 Has_Biased_Representation (gnat_entity));
620 if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0))
621 gnu_size = NULL_TREE;
624 /* If this object has self-referential size, it must be a record with
625 a default value. We are supposed to allocate an object of the
626 maximum size in this case unless it is a constant with an
627 initializing expression, in which case we can get the size from
628 that. Note that the resulting size may still be a variable, so
629 this may end up with an indirect allocation. */
630 if (No (Renamed_Object (gnat_entity))
631 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
633 if (gnu_expr && kind == E_Constant)
635 tree size = TYPE_SIZE (TREE_TYPE (gnu_expr));
636 if (CONTAINS_PLACEHOLDER_P (size))
638 /* If the initializing expression is itself a constant,
639 despite having a nominal type with self-referential
640 size, we can get the size directly from it. */
641 if (TREE_CODE (gnu_expr) == COMPONENT_REF
642 && TREE_CODE (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
645 (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
646 && TREE_CODE (TREE_OPERAND (gnu_expr, 0)) == VAR_DECL
647 && (TREE_READONLY (TREE_OPERAND (gnu_expr, 0))
648 || DECL_READONLY_ONCE_ELAB
649 (TREE_OPERAND (gnu_expr, 0))))
650 gnu_size = DECL_SIZE (TREE_OPERAND (gnu_expr, 0));
653 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, gnu_expr);
658 /* We may have no GNU_EXPR because No_Initialization is
659 set even though there's an Expression. */
660 else if (kind == E_Constant
661 && (Nkind (Declaration_Node (gnat_entity))
662 == N_Object_Declaration)
663 && Present (Expression (Declaration_Node (gnat_entity))))
665 = TYPE_SIZE (gnat_to_gnu_type
667 (Expression (Declaration_Node (gnat_entity)))));
670 gnu_size = max_size (TYPE_SIZE (gnu_type), true);
675 /* If the size is zero bytes, make it one byte since some linkers have
676 trouble with zero-sized objects. If the object will have a
677 template, that will make it nonzero so don't bother. Also avoid
678 doing that for an object renaming or an object with an address
679 clause, as we would lose useful information on the view size
680 (e.g. for null array slices) and we are not allocating the object
683 && integer_zerop (gnu_size)
684 && !TREE_OVERFLOW (gnu_size))
685 || (TYPE_SIZE (gnu_type)
686 && integer_zerop (TYPE_SIZE (gnu_type))
687 && !TREE_OVERFLOW (TYPE_SIZE (gnu_type))))
688 && (!Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
689 || !Is_Array_Type (Etype (gnat_entity)))
690 && !Present (Renamed_Object (gnat_entity))
691 && !Present (Address_Clause (gnat_entity)))
692 gnu_size = bitsize_unit_node;
694 /* If this is an object with no specified size and alignment, and
695 if either it is atomic or we are not optimizing alignment for
696 space and it is composite and not an exception, an Out parameter
697 or a reference to another object, and the size of its type is a
698 constant, set the alignment to the smallest one which is not
699 smaller than the size, with an appropriate cap. */
700 if (!gnu_size && align == 0
701 && (Is_Atomic (gnat_entity)
702 || (!Optimize_Alignment_Space (gnat_entity)
703 && kind != E_Exception
704 && kind != E_Out_Parameter
705 && Is_Composite_Type (Etype (gnat_entity))
706 && !Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
708 && No (Renamed_Object (gnat_entity))
709 && No (Address_Clause (gnat_entity))))
710 && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST)
712 /* No point in jumping through all the hoops needed in order
713 to support BIGGEST_ALIGNMENT if we don't really have to.
714 So we cap to the smallest alignment that corresponds to
715 a known efficient memory access pattern of the target. */
716 unsigned int align_cap = Is_Atomic (gnat_entity)
718 : get_mode_alignment (ptr_mode);
720 if (!host_integerp (TYPE_SIZE (gnu_type), 1)
721 || compare_tree_int (TYPE_SIZE (gnu_type), align_cap) >= 0)
724 align = ceil_alignment (tree_low_cst (TYPE_SIZE (gnu_type), 1));
726 /* But make sure not to under-align the object. */
727 if (align <= TYPE_ALIGN (gnu_type))
730 /* And honor the minimum valid atomic alignment, if any. */
731 #ifdef MINIMUM_ATOMIC_ALIGNMENT
732 else if (align < MINIMUM_ATOMIC_ALIGNMENT)
733 align = MINIMUM_ATOMIC_ALIGNMENT;
737 /* If the object is set to have atomic components, find the component
738 type and validate it.
740 ??? Note that we ignore Has_Volatile_Components on objects; it's
741 not at all clear what to do in that case. */
743 if (Has_Atomic_Components (gnat_entity))
745 tree gnu_inner = (TREE_CODE (gnu_type) == ARRAY_TYPE
746 ? TREE_TYPE (gnu_type) : gnu_type);
748 while (TREE_CODE (gnu_inner) == ARRAY_TYPE
749 && TYPE_MULTI_ARRAY_P (gnu_inner))
750 gnu_inner = TREE_TYPE (gnu_inner);
752 check_ok_for_atomic (gnu_inner, gnat_entity, true);
755 /* Now check if the type of the object allows atomic access. Note
756 that we must test the type, even if this object has size and
757 alignment to allow such access, because we will be going
758 inside the padded record to assign to the object. We could fix
759 this by always copying via an intermediate value, but it's not
760 clear it's worth the effort. */
761 if (Is_Atomic (gnat_entity))
762 check_ok_for_atomic (gnu_type, gnat_entity, false);
764 /* If this is an aliased object with an unconstrained nominal subtype,
765 make a type that includes the template. */
766 if (Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
767 && Is_Array_Type (Etype (gnat_entity))
768 && !type_annotate_only)
771 = TREE_TYPE (gnat_to_gnu_type (Base_Type (Etype (gnat_entity))));
774 = build_unc_object_type_from_ptr (gnu_fat, gnu_type,
775 concat_id_with_name (gnu_entity_id,
779 #ifdef MINIMUM_ATOMIC_ALIGNMENT
780 /* If the size is a constant and no alignment is specified, force
781 the alignment to be the minimum valid atomic alignment. The
782 restriction on constant size avoids problems with variable-size
783 temporaries; if the size is variable, there's no issue with
784 atomic access. Also don't do this for a constant, since it isn't
785 necessary and can interfere with constant replacement. Finally,
786 do not do it for Out parameters since that creates an
787 size inconsistency with In parameters. */
788 if (align == 0 && MINIMUM_ATOMIC_ALIGNMENT > TYPE_ALIGN (gnu_type)
789 && !FLOAT_TYPE_P (gnu_type)
790 && !const_flag && No (Renamed_Object (gnat_entity))
791 && !imported_p && No (Address_Clause (gnat_entity))
792 && kind != E_Out_Parameter
793 && (gnu_size ? TREE_CODE (gnu_size) == INTEGER_CST
794 : TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST))
795 align = MINIMUM_ATOMIC_ALIGNMENT;
798 /* Make a new type with the desired size and alignment, if needed.
799 But do not take into account alignment promotions to compute the
800 size of the object. */
801 gnu_object_size = gnu_size ? gnu_size : TYPE_SIZE (gnu_type);
802 if (gnu_size || align > 0)
803 gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity,
804 "PAD", false, definition,
805 gnu_size ? true : false);
807 /* If this is a renaming, avoid as much as possible to create a new
808 object. However, in several cases, creating it is required.
809 This processing needs to be applied to the raw expression so
810 as to make it more likely to rename the underlying object. */
811 if (Present (Renamed_Object (gnat_entity)))
813 bool create_normal_object = false;
815 /* If the renamed object had padding, strip off the reference
816 to the inner object and reset our type. */
817 if ((TREE_CODE (gnu_expr) == COMPONENT_REF
818 && TREE_CODE (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
820 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0))))
821 /* Strip useless conversions around the object. */
822 || (TREE_CODE (gnu_expr) == NOP_EXPR
823 && gnat_types_compatible_p
824 (TREE_TYPE (gnu_expr),
825 TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))))
827 gnu_expr = TREE_OPERAND (gnu_expr, 0);
828 gnu_type = TREE_TYPE (gnu_expr);
831 /* Case 1: If this is a constant renaming stemming from a function
832 call, treat it as a normal object whose initial value is what
833 is being renamed. RM 3.3 says that the result of evaluating a
834 function call is a constant object. As a consequence, it can
835 be the inner object of a constant renaming. In this case, the
836 renaming must be fully instantiated, i.e. it cannot be a mere
837 reference to (part of) an existing object. */
840 tree inner_object = gnu_expr;
841 while (handled_component_p (inner_object))
842 inner_object = TREE_OPERAND (inner_object, 0);
843 if (TREE_CODE (inner_object) == CALL_EXPR)
844 create_normal_object = true;
847 /* Otherwise, see if we can proceed with a stabilized version of
848 the renamed entity or if we need to make a new object. */
849 if (!create_normal_object)
851 tree maybe_stable_expr = NULL_TREE;
854 /* Case 2: If the renaming entity need not be materialized and
855 the renamed expression is something we can stabilize, use
856 that for the renaming. At the global level, we can only do
857 this if we know no SAVE_EXPRs need be made, because the
858 expression we return might be used in arbitrary conditional
859 branches so we must force the SAVE_EXPRs evaluation
860 immediately and this requires a function context. */
861 if (!Materialize_Entity (gnat_entity)
862 && (!global_bindings_p ()
863 || (staticp (gnu_expr)
864 && !TREE_SIDE_EFFECTS (gnu_expr))))
867 = maybe_stabilize_reference (gnu_expr, true, &stable);
871 gnu_decl = maybe_stable_expr;
872 /* ??? No DECL_EXPR is created so we need to mark
873 the expression manually lest it is shared. */
874 if (global_bindings_p ())
875 mark_visited (&gnu_decl);
876 save_gnu_tree (gnat_entity, gnu_decl, true);
881 /* The stabilization failed. Keep maybe_stable_expr
882 untouched here to let the pointer case below know
883 about that failure. */
886 /* Case 3: If this is a constant renaming and creating a
887 new object is allowed and cheap, treat it as a normal
888 object whose initial value is what is being renamed. */
890 && !Is_Composite_Type
891 (Underlying_Type (Etype (gnat_entity))))
894 /* Case 4: Make this into a constant pointer to the object we
895 are to rename and attach the object to the pointer if it is
896 something we can stabilize.
898 From the proper scope, attached objects will be referenced
899 directly instead of indirectly via the pointer to avoid
900 subtle aliasing problems with non-addressable entities.
901 They have to be stable because we must not evaluate the
902 variables in the expression every time the renaming is used.
903 The pointer is called a "renaming" pointer in this case.
905 In the rare cases where we cannot stabilize the renamed
906 object, we just make a "bare" pointer, and the renamed
907 entity is always accessed indirectly through it. */
910 gnu_type = build_reference_type (gnu_type);
911 inner_const_flag = TREE_READONLY (gnu_expr);
914 /* If the previous attempt at stabilizing failed, there
915 is no point in trying again and we reuse the result
916 without attaching it to the pointer. In this case it
917 will only be used as the initializing expression of
918 the pointer and thus needs no special treatment with
919 regard to multiple evaluations. */
920 if (maybe_stable_expr)
923 /* Otherwise, try to stabilize and attach the expression
924 to the pointer if the stabilization succeeds.
926 Note that this might introduce SAVE_EXPRs and we don't
927 check whether we're at the global level or not. This
928 is fine since we are building a pointer initializer and
929 neither the pointer nor the initializing expression can
930 be accessed before the pointer elaboration has taken
931 place in a correct program.
933 These SAVE_EXPRs will be evaluated at the right place
934 by either the evaluation of the initializer for the
935 non-global case or the elaboration code for the global
936 case, and will be attached to the elaboration procedure
937 in the latter case. */
941 = maybe_stabilize_reference (gnu_expr, true, &stable);
944 renamed_obj = maybe_stable_expr;
946 /* Attaching is actually performed downstream, as soon
947 as we have a VAR_DECL for the pointer we make. */
951 = build_unary_op (ADDR_EXPR, gnu_type, maybe_stable_expr);
953 gnu_size = NULL_TREE;
959 /* Make a volatile version of this object's type if we are to make
960 the object volatile. We also interpret 13.3(19) conservatively
961 and disallow any optimizations for an object covered by it. */
962 if ((Treat_As_Volatile (gnat_entity)
963 || (Is_Exported (gnat_entity)
964 /* Exclude exported constants created by the compiler,
965 which should boil down to static dispatch tables and
966 make it possible to put them in read-only memory. */
967 && (Comes_From_Source (gnat_entity) || !const_flag))
968 || Is_Imported (gnat_entity)
969 || Present (Address_Clause (gnat_entity)))
970 && !TYPE_VOLATILE (gnu_type))
971 gnu_type = build_qualified_type (gnu_type,
972 (TYPE_QUALS (gnu_type)
973 | TYPE_QUAL_VOLATILE));
975 /* If we are defining an aliased object whose nominal subtype is
976 unconstrained, the object is a record that contains both the
977 template and the object. If there is an initializer, it will
978 have already been converted to the right type, but we need to
979 create the template if there is no initializer. */
982 && TREE_CODE (gnu_type) == RECORD_TYPE
983 && (TYPE_CONTAINS_TEMPLATE_P (gnu_type)
984 /* Beware that padding might have been introduced
985 via maybe_pad_type above. */
986 || (TYPE_IS_PADDING_P (gnu_type)
987 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (gnu_type)))
989 && TYPE_CONTAINS_TEMPLATE_P
990 (TREE_TYPE (TYPE_FIELDS (gnu_type))))))
993 = TYPE_IS_PADDING_P (gnu_type)
994 ? TYPE_FIELDS (TREE_TYPE (TYPE_FIELDS (gnu_type)))
995 : TYPE_FIELDS (gnu_type);
998 = gnat_build_constructor
1002 build_template (TREE_TYPE (template_field),
1003 TREE_TYPE (TREE_CHAIN (template_field)),
1008 /* Convert the expression to the type of the object except in the
1009 case where the object's type is unconstrained or the object's type
1010 is a padded record whose field is of self-referential size. In
1011 the former case, converting will generate unnecessary evaluations
1012 of the CONSTRUCTOR to compute the size and in the latter case, we
1013 want to only copy the actual data. */
1015 && TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE
1016 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
1017 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1018 && TYPE_IS_PADDING_P (gnu_type)
1019 && (CONTAINS_PLACEHOLDER_P
1020 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (gnu_type)))))))
1021 gnu_expr = convert (gnu_type, gnu_expr);
1023 /* If this is a pointer and it does not have an initializing
1024 expression, initialize it to NULL, unless the object is
1027 && (POINTER_TYPE_P (gnu_type) || TYPE_FAT_POINTER_P (gnu_type))
1028 && !Is_Imported (gnat_entity) && !gnu_expr)
1029 gnu_expr = integer_zero_node;
1031 /* If we are defining the object and it has an Address clause, we must
1032 either get the address expression from the saved GCC tree for the
1033 object if it has a Freeze node, or elaborate the address expression
1034 here since the front-end has guaranteed that the elaboration has no
1035 effects in this case. */
1036 if (definition && Present (Address_Clause (gnat_entity)))
1039 = present_gnu_tree (gnat_entity)
1040 ? get_gnu_tree (gnat_entity)
1041 : gnat_to_gnu (Expression (Address_Clause (gnat_entity)));
1043 save_gnu_tree (gnat_entity, NULL_TREE, false);
1045 /* Ignore the size. It's either meaningless or was handled
1047 gnu_size = NULL_TREE;
1048 /* Convert the type of the object to a reference type that can
1049 alias everything as per 13.3(19). */
1051 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
1052 gnu_address = convert (gnu_type, gnu_address);
1054 const_flag = !Is_Public (gnat_entity)
1055 || compile_time_known_address_p (Expression (Address_Clause
1058 /* If this is a deferred constant, the initializer is attached to
1060 if (kind == E_Constant && Present (Full_View (gnat_entity)))
1063 (Expression (Declaration_Node (Full_View (gnat_entity))));
1065 /* If we don't have an initializing expression for the underlying
1066 variable, the initializing expression for the pointer is the
1067 specified address. Otherwise, we have to make a COMPOUND_EXPR
1068 to assign both the address and the initial value. */
1070 gnu_expr = gnu_address;
1073 = build2 (COMPOUND_EXPR, gnu_type,
1075 (MODIFY_EXPR, NULL_TREE,
1076 build_unary_op (INDIRECT_REF, NULL_TREE,
1082 /* If it has an address clause and we are not defining it, mark it
1083 as an indirect object. Likewise for Stdcall objects that are
1085 if ((!definition && Present (Address_Clause (gnat_entity)))
1086 || (Is_Imported (gnat_entity)
1087 && Has_Stdcall_Convention (gnat_entity)))
1089 /* Convert the type of the object to a reference type that can
1090 alias everything as per 13.3(19). */
1092 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
1093 gnu_size = NULL_TREE;
1095 /* No point in taking the address of an initializing expression
1096 that isn't going to be used. */
1097 gnu_expr = NULL_TREE;
1099 /* If it has an address clause whose value is known at compile
1100 time, make the object a CONST_DECL. This will avoid a
1101 useless dereference. */
1102 if (Present (Address_Clause (gnat_entity)))
1104 Node_Id gnat_address
1105 = Expression (Address_Clause (gnat_entity));
1107 if (compile_time_known_address_p (gnat_address))
1109 gnu_expr = gnat_to_gnu (gnat_address);
1117 /* If we are at top level and this object is of variable size,
1118 make the actual type a hidden pointer to the real type and
1119 make the initializer be a memory allocation and initialization.
1120 Likewise for objects we aren't defining (presumed to be
1121 external references from other packages), but there we do
1122 not set up an initialization.
1124 If the object's size overflows, make an allocator too, so that
1125 Storage_Error gets raised. Note that we will never free
1126 such memory, so we presume it never will get allocated. */
1128 if (!allocatable_size_p (TYPE_SIZE_UNIT (gnu_type),
1129 global_bindings_p () || !definition
1132 && ! allocatable_size_p (gnu_size,
1133 global_bindings_p () || !definition
1136 gnu_type = build_reference_type (gnu_type);
1137 gnu_size = NULL_TREE;
1141 /* In case this was a aliased object whose nominal subtype is
1142 unconstrained, the pointer above will be a thin pointer and
1143 build_allocator will automatically make the template.
1145 If we have a template initializer only (that we made above),
1146 pretend there is none and rely on what build_allocator creates
1147 again anyway. Otherwise (if we have a full initializer), get
1148 the data part and feed that to build_allocator.
1150 If we are elaborating a mutable object, tell build_allocator to
1151 ignore a possibly simpler size from the initializer, if any, as
1152 we must allocate the maximum possible size in this case. */
1156 tree gnu_alloc_type = TREE_TYPE (gnu_type);
1158 if (TREE_CODE (gnu_alloc_type) == RECORD_TYPE
1159 && TYPE_CONTAINS_TEMPLATE_P (gnu_alloc_type))
1162 = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_alloc_type)));
1164 if (TREE_CODE (gnu_expr) == CONSTRUCTOR
1165 && 1 == VEC_length (constructor_elt,
1166 CONSTRUCTOR_ELTS (gnu_expr)))
1170 = build_component_ref
1171 (gnu_expr, NULL_TREE,
1172 TREE_CHAIN (TYPE_FIELDS (TREE_TYPE (gnu_expr))),
1176 if (TREE_CODE (TYPE_SIZE_UNIT (gnu_alloc_type)) == INTEGER_CST
1177 && TREE_OVERFLOW (TYPE_SIZE_UNIT (gnu_alloc_type))
1178 && !Is_Imported (gnat_entity))
1179 post_error ("?Storage_Error will be raised at run-time!",
1182 gnu_expr = build_allocator (gnu_alloc_type, gnu_expr, gnu_type,
1183 0, 0, gnat_entity, mutable_p);
1187 gnu_expr = NULL_TREE;
1192 /* If this object would go into the stack and has an alignment larger
1193 than the largest stack alignment the back-end can honor, resort to
1194 a variable of "aligning type". */
1195 if (!global_bindings_p () && !static_p && definition
1196 && !imported_p && TYPE_ALIGN (gnu_type) > BIGGEST_ALIGNMENT)
1198 /* Create the new variable. No need for extra room before the
1199 aligned field as this is in automatic storage. */
1201 = make_aligning_type (gnu_type, TYPE_ALIGN (gnu_type),
1202 TYPE_SIZE_UNIT (gnu_type),
1203 BIGGEST_ALIGNMENT, 0);
1205 = create_var_decl (create_concat_name (gnat_entity, "ALIGN"),
1206 NULL_TREE, gnu_new_type, NULL_TREE, false,
1207 false, false, false, NULL, gnat_entity);
1209 /* Initialize the aligned field if we have an initializer. */
1212 (build_binary_op (MODIFY_EXPR, NULL_TREE,
1214 (gnu_new_var, NULL_TREE,
1215 TYPE_FIELDS (gnu_new_type), false),
1219 /* And setup this entity as a reference to the aligned field. */
1220 gnu_type = build_reference_type (gnu_type);
1223 (ADDR_EXPR, gnu_type,
1224 build_component_ref (gnu_new_var, NULL_TREE,
1225 TYPE_FIELDS (gnu_new_type), false));
1227 gnu_size = NULL_TREE;
1233 gnu_type = build_qualified_type (gnu_type, (TYPE_QUALS (gnu_type)
1234 | TYPE_QUAL_CONST));
1236 /* Convert the expression to the type of the object except in the
1237 case where the object's type is unconstrained or the object's type
1238 is a padded record whose field is of self-referential size. In
1239 the former case, converting will generate unnecessary evaluations
1240 of the CONSTRUCTOR to compute the size and in the latter case, we
1241 want to only copy the actual data. */
1243 && TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE
1244 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
1245 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1246 && TYPE_IS_PADDING_P (gnu_type)
1247 && (CONTAINS_PLACEHOLDER_P
1248 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (gnu_type)))))))
1249 gnu_expr = convert (gnu_type, gnu_expr);
1251 /* If this name is external or there was a name specified, use it,
1252 unless this is a VMS exception object since this would conflict
1253 with the symbol we need to export in addition. Don't use the
1254 Interface_Name if there is an address clause (see CD30005). */
1255 if (!Is_VMS_Exception (gnat_entity)
1256 && ((Present (Interface_Name (gnat_entity))
1257 && No (Address_Clause (gnat_entity)))
1258 || (Is_Public (gnat_entity)
1259 && (!Is_Imported (gnat_entity)
1260 || Is_Exported (gnat_entity)))))
1261 gnu_ext_name = create_concat_name (gnat_entity, 0);
1263 /* If this is constant initialized to a static constant and the
1264 object has an aggregate type, force it to be statically
1265 allocated. This will avoid an initialization copy. */
1266 if (!static_p && const_flag
1267 && gnu_expr && TREE_CONSTANT (gnu_expr)
1268 && AGGREGATE_TYPE_P (gnu_type)
1269 && host_integerp (TYPE_SIZE_UNIT (gnu_type), 1)
1270 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1271 && TYPE_IS_PADDING_P (gnu_type)
1272 && !host_integerp (TYPE_SIZE_UNIT
1273 (TREE_TYPE (TYPE_FIELDS (gnu_type))), 1)))
1276 gnu_decl = create_var_decl (gnu_entity_id, gnu_ext_name, gnu_type,
1277 gnu_expr, const_flag,
1278 Is_Public (gnat_entity),
1279 imported_p || !definition,
1280 static_p, attr_list, gnat_entity);
1281 DECL_BY_REF_P (gnu_decl) = used_by_ref;
1282 DECL_POINTS_TO_READONLY_P (gnu_decl) = used_by_ref && inner_const_flag;
1283 if (TREE_CODE (gnu_decl) == VAR_DECL && renamed_obj)
1285 SET_DECL_RENAMED_OBJECT (gnu_decl, renamed_obj);
1286 if (global_bindings_p ())
1288 DECL_RENAMING_GLOBAL_P (gnu_decl) = 1;
1289 record_global_renaming_pointer (gnu_decl);
1293 if (definition && DECL_SIZE_UNIT (gnu_decl)
1294 && get_block_jmpbuf_decl ()
1295 && (TREE_CODE (DECL_SIZE_UNIT (gnu_decl)) != INTEGER_CST
1296 || (flag_stack_check == GENERIC_STACK_CHECK
1297 && compare_tree_int (DECL_SIZE_UNIT (gnu_decl),
1298 STACK_CHECK_MAX_VAR_SIZE) > 0)))
1299 add_stmt_with_node (build_call_1_expr
1300 (update_setjmp_buf_decl,
1301 build_unary_op (ADDR_EXPR, NULL_TREE,
1302 get_block_jmpbuf_decl ())),
1305 /* If we are defining an Out parameter and we're not optimizing,
1306 create a fake PARM_DECL for debugging purposes and make it
1307 point to the VAR_DECL. Suppress debug info for the latter
1308 but make sure it will still live on the stack so it can be
1309 accessed from within the debugger through the PARM_DECL. */
1310 if (kind == E_Out_Parameter && definition && !optimize)
1312 tree param = create_param_decl (gnu_entity_id, gnu_type, false);
1313 gnat_pushdecl (param, gnat_entity);
1314 SET_DECL_VALUE_EXPR (param, gnu_decl);
1315 DECL_HAS_VALUE_EXPR_P (param) = 1;
1317 debug_info_p = false;
1319 DECL_IGNORED_P (param) = 1;
1320 TREE_ADDRESSABLE (gnu_decl) = 1;
1323 /* If this is a public constant or we're not optimizing and we're not
1324 making a VAR_DECL for it, make one just for export or debugger use.
1325 Likewise if the address is taken or if either the object or type is
1326 aliased. Make an external declaration for a reference, unless this
1327 is a Standard entity since there no real symbol at the object level
1329 if (TREE_CODE (gnu_decl) == CONST_DECL
1330 && (definition || Sloc (gnat_entity) > Standard_Location)
1331 && ((Is_Public (gnat_entity)
1332 && !Present (Address_Clause (gnat_entity)))
1334 || Address_Taken (gnat_entity)
1335 || Is_Aliased (gnat_entity)
1336 || Is_Aliased (Etype (gnat_entity))))
1339 = create_true_var_decl (gnu_entity_id, gnu_ext_name, gnu_type,
1340 gnu_expr, true, Is_Public (gnat_entity),
1341 !definition, static_p, NULL,
1344 SET_DECL_CONST_CORRESPONDING_VAR (gnu_decl, gnu_corr_var);
1346 /* As debugging information will be generated for the variable,
1347 do not generate information for the constant. */
1348 DECL_IGNORED_P (gnu_decl) = 1;
1351 /* If this is declared in a block that contains a block with an
1352 exception handler, we must force this variable in memory to
1353 suppress an invalid optimization. */
1354 if (Has_Nested_Block_With_Handler (Scope (gnat_entity))
1355 && Exception_Mechanism != Back_End_Exceptions)
1356 TREE_ADDRESSABLE (gnu_decl) = 1;
1358 gnu_type = TREE_TYPE (gnu_decl);
1360 /* Back-annotate Alignment and Esize of the object if not already
1361 known, except for when the object is actually a pointer to the
1362 real object, since alignment and size of a pointer don't have
1363 anything to do with those of the designated object. Note that
1364 we pick the values of the type, not those of the object, to
1365 shield ourselves from low-level platform-dependent adjustments
1366 like alignment promotion. This is both consistent with all the
1367 treatment above, where alignment and size are set on the type of
1368 the object and not on the object directly, and makes it possible
1369 to support confirming representation clauses in all cases. */
1371 if (!used_by_ref && Unknown_Alignment (gnat_entity))
1372 Set_Alignment (gnat_entity,
1373 UI_From_Int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT));
1375 if (!used_by_ref && Unknown_Esize (gnat_entity))
1377 if (TREE_CODE (gnu_type) == RECORD_TYPE
1378 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
1380 = TYPE_SIZE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type))));
1382 Set_Esize (gnat_entity, annotate_value (gnu_object_size));
1388 /* Return a TYPE_DECL for "void" that we previously made. */
1389 gnu_decl = TYPE_NAME (void_type_node);
1392 case E_Enumeration_Type:
1393 /* A special case, for the types Character and Wide_Character in
1394 Standard, we do not list all the literals. So if the literals
1395 are not specified, make this an unsigned type. */
1396 if (No (First_Literal (gnat_entity)))
1398 gnu_type = make_unsigned_type (esize);
1399 TYPE_NAME (gnu_type) = gnu_entity_id;
1401 /* Set TYPE_STRING_FLAG for Ada Character and Wide_Character types.
1402 This is needed by the DWARF-2 back-end to distinguish between
1403 unsigned integer types and character types. */
1404 TYPE_STRING_FLAG (gnu_type) = 1;
1408 /* Normal case of non-character type, or non-Standard character type */
1410 /* Here we have a list of enumeral constants in First_Literal.
1411 We make a CONST_DECL for each and build into GNU_LITERAL_LIST
1412 the list to be places into TYPE_FIELDS. Each node in the list
1413 is a TREE_LIST node whose TREE_VALUE is the literal name
1414 and whose TREE_PURPOSE is the value of the literal.
1416 Esize contains the number of bits needed to represent the enumeral
1417 type, Type_Low_Bound also points to the first literal and
1418 Type_High_Bound points to the last literal. */
1420 Entity_Id gnat_literal;
1421 tree gnu_literal_list = NULL_TREE;
1423 if (Is_Unsigned_Type (gnat_entity))
1424 gnu_type = make_unsigned_type (esize);
1426 gnu_type = make_signed_type (esize);
1428 TREE_SET_CODE (gnu_type, ENUMERAL_TYPE);
1430 for (gnat_literal = First_Literal (gnat_entity);
1431 Present (gnat_literal);
1432 gnat_literal = Next_Literal (gnat_literal))
1434 tree gnu_value = UI_To_gnu (Enumeration_Rep (gnat_literal),
1437 = create_var_decl (get_entity_name (gnat_literal), NULL_TREE,
1438 gnu_type, gnu_value, true, false, false,
1439 false, NULL, gnat_literal);
1441 save_gnu_tree (gnat_literal, gnu_literal, false);
1442 gnu_literal_list = tree_cons (DECL_NAME (gnu_literal),
1443 gnu_value, gnu_literal_list);
1446 TYPE_VALUES (gnu_type) = nreverse (gnu_literal_list);
1448 /* Note that the bounds are updated at the end of this function
1449 because to avoid an infinite recursion when we get the bounds of
1450 this type, since those bounds are objects of this type. */
1454 case E_Signed_Integer_Type:
1455 case E_Ordinary_Fixed_Point_Type:
1456 case E_Decimal_Fixed_Point_Type:
1457 /* For integer types, just make a signed type the appropriate number
1459 gnu_type = make_signed_type (esize);
1462 case E_Modular_Integer_Type:
1463 /* For modular types, make the unsigned type of the proper number of
1464 bits and then set up the modulus, if required. */
1466 enum machine_mode mode;
1470 if (Is_Packed_Array_Type (gnat_entity))
1471 esize = UI_To_Int (RM_Size (gnat_entity));
1473 /* Find the smallest mode at least ESIZE bits wide and make a class
1476 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1477 GET_MODE_BITSIZE (mode) < esize;
1478 mode = GET_MODE_WIDER_MODE (mode))
1481 gnu_type = make_unsigned_type (GET_MODE_BITSIZE (mode));
1482 TYPE_PACKED_ARRAY_TYPE_P (gnu_type)
1483 = (Is_Packed_Array_Type (gnat_entity)
1484 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)));
1486 /* Get the modulus in this type. If it overflows, assume it is because
1487 it is equal to 2**Esize. Note that there is no overflow checking
1488 done on unsigned type, so we detect the overflow by looking for
1489 a modulus of zero, which is otherwise invalid. */
1490 gnu_modulus = UI_To_gnu (Modulus (gnat_entity), gnu_type);
1492 if (!integer_zerop (gnu_modulus))
1494 TYPE_MODULAR_P (gnu_type) = 1;
1495 SET_TYPE_MODULUS (gnu_type, gnu_modulus);
1496 gnu_high = fold_build2 (MINUS_EXPR, gnu_type, gnu_modulus,
1497 convert (gnu_type, integer_one_node));
1500 /* If we have to set TYPE_PRECISION different from its natural value,
1501 make a subtype to do do. Likewise if there is a modulus and
1502 it is not one greater than TYPE_MAX_VALUE. */
1503 if (TYPE_PRECISION (gnu_type) != esize
1504 || (TYPE_MODULAR_P (gnu_type)
1505 && !tree_int_cst_equal (TYPE_MAX_VALUE (gnu_type), gnu_high)))
1507 tree gnu_subtype = make_node (INTEGER_TYPE);
1509 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "UMT");
1510 TREE_TYPE (gnu_subtype) = gnu_type;
1511 TYPE_MIN_VALUE (gnu_subtype) = TYPE_MIN_VALUE (gnu_type);
1512 TYPE_MAX_VALUE (gnu_subtype)
1513 = TYPE_MODULAR_P (gnu_type)
1514 ? gnu_high : TYPE_MAX_VALUE (gnu_type);
1515 TYPE_PRECISION (gnu_subtype) = esize;
1516 TYPE_UNSIGNED (gnu_subtype) = 1;
1517 TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1;
1518 TYPE_PACKED_ARRAY_TYPE_P (gnu_subtype)
1519 = (Is_Packed_Array_Type (gnat_entity)
1520 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)));
1521 layout_type (gnu_subtype);
1523 gnu_type = gnu_subtype;
1528 case E_Signed_Integer_Subtype:
1529 case E_Enumeration_Subtype:
1530 case E_Modular_Integer_Subtype:
1531 case E_Ordinary_Fixed_Point_Subtype:
1532 case E_Decimal_Fixed_Point_Subtype:
1534 /* For integral subtypes, we make a new INTEGER_TYPE. Note
1535 that we do not want to call build_range_type since we would
1536 like each subtype node to be distinct. This will be important
1537 when memory aliasing is implemented.
1539 The TREE_TYPE field of the INTEGER_TYPE we make points to the
1540 parent type; this fact is used by the arithmetic conversion
1543 We elaborate the Ancestor_Subtype if it is not in the current
1544 unit and one of our bounds is non-static. We do this to ensure
1545 consistent naming in the case where several subtypes share the same
1546 bounds by always elaborating the first such subtype first, thus
1550 && Present (Ancestor_Subtype (gnat_entity))
1551 && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity))
1552 && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity))
1553 || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity))))
1554 gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity),
1557 gnu_type = make_node (INTEGER_TYPE);
1558 TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity));
1560 /* Set the precision to the Esize except for bit-packed arrays and
1561 subtypes of Standard.Boolean. */
1562 if (Is_Packed_Array_Type (gnat_entity)
1563 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
1565 esize = UI_To_Int (RM_Size (gnat_entity));
1566 TYPE_PACKED_ARRAY_TYPE_P (gnu_type) = 1;
1568 else if (TREE_CODE (TREE_TYPE (gnu_type)) == BOOLEAN_TYPE)
1571 TYPE_PRECISION (gnu_type) = esize;
1573 TYPE_MIN_VALUE (gnu_type)
1574 = convert (TREE_TYPE (gnu_type),
1575 elaborate_expression (Type_Low_Bound (gnat_entity),
1577 get_identifier ("L"), definition, 1,
1578 Needs_Debug_Info (gnat_entity)));
1580 TYPE_MAX_VALUE (gnu_type)
1581 = convert (TREE_TYPE (gnu_type),
1582 elaborate_expression (Type_High_Bound (gnat_entity),
1584 get_identifier ("U"), definition, 1,
1585 Needs_Debug_Info (gnat_entity)));
1587 /* One of the above calls might have caused us to be elaborated,
1588 so don't blow up if so. */
1589 if (present_gnu_tree (gnat_entity))
1591 maybe_present = true;
1595 TYPE_BIASED_REPRESENTATION_P (gnu_type)
1596 = Has_Biased_Representation (gnat_entity);
1598 /* This should be an unsigned type if the lower bound is constant
1599 and non-negative or if the base type is unsigned; a signed type
1601 TYPE_UNSIGNED (gnu_type)
1602 = (TYPE_UNSIGNED (TREE_TYPE (gnu_type))
1603 || (TREE_CODE (TYPE_MIN_VALUE (gnu_type)) == INTEGER_CST
1604 && TREE_INT_CST_HIGH (TYPE_MIN_VALUE (gnu_type)) >= 0)
1605 || TYPE_BIASED_REPRESENTATION_P (gnu_type)
1606 || Is_Unsigned_Type (gnat_entity));
1608 layout_type (gnu_type);
1610 /* Inherit our alias set from what we're a subtype of. Subtypes
1611 are not different types and a pointer can designate any instance
1612 within a subtype hierarchy. */
1613 relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY);
1615 /* If the type we are dealing with is to represent a packed array,
1616 we need to have the bits left justified on big-endian targets
1617 and right justified on little-endian targets. We also need to
1618 ensure that when the value is read (e.g. for comparison of two
1619 such values), we only get the good bits, since the unused bits
1620 are uninitialized. Both goals are accomplished by wrapping the
1621 modular value in an enclosing struct. */
1622 if (Is_Packed_Array_Type (gnat_entity)
1623 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
1625 tree gnu_field_type = gnu_type;
1628 TYPE_RM_SIZE_NUM (gnu_field_type)
1629 = UI_To_gnu (RM_Size (gnat_entity), bitsizetype);
1630 gnu_type = make_node (RECORD_TYPE);
1631 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "JM");
1633 /* Propagate the alignment of the modular type to the record.
1634 This means that bitpacked arrays have "ceil" alignment for
1635 their size, which may seem counter-intuitive but makes it
1636 possible to easily overlay them on modular types. */
1637 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (gnu_field_type);
1638 TYPE_PACKED (gnu_type) = 1;
1640 /* Create a stripped-down declaration of the original type, mainly
1642 create_type_decl (get_entity_name (gnat_entity), gnu_field_type,
1643 NULL, true, debug_info_p, gnat_entity);
1645 /* Don't notify the field as "addressable", since we won't be taking
1646 it's address and it would prevent create_field_decl from making a
1648 gnu_field = create_field_decl (get_identifier ("OBJECT"),
1649 gnu_field_type, gnu_type, 1, 0, 0, 0);
1651 finish_record_type (gnu_type, gnu_field, 0, false);
1652 TYPE_JUSTIFIED_MODULAR_P (gnu_type) = 1;
1653 SET_TYPE_ADA_SIZE (gnu_type, bitsize_int (esize));
1655 relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY);
1658 /* If the type we are dealing with has got a smaller alignment than the
1659 natural one, we need to wrap it up in a record type and under-align
1660 the latter. We reuse the padding machinery for this purpose. */
1661 else if (Known_Alignment (gnat_entity)
1662 && UI_Is_In_Int_Range (Alignment (gnat_entity))
1663 && (align = UI_To_Int (Alignment (gnat_entity)) * BITS_PER_UNIT)
1664 && align < TYPE_ALIGN (gnu_type))
1666 tree gnu_field_type = gnu_type;
1669 gnu_type = make_node (RECORD_TYPE);
1670 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "PAD");
1672 TYPE_ALIGN (gnu_type) = align;
1673 TYPE_PACKED (gnu_type) = 1;
1675 /* Create a stripped-down declaration of the original type, mainly
1677 create_type_decl (get_entity_name (gnat_entity), gnu_field_type,
1678 NULL, true, debug_info_p, gnat_entity);
1680 /* Don't notify the field as "addressable", since we won't be taking
1681 it's address and it would prevent create_field_decl from making a
1683 gnu_field = create_field_decl (get_identifier ("OBJECT"),
1684 gnu_field_type, gnu_type, 1, 0, 0, 0);
1686 finish_record_type (gnu_type, gnu_field, 0, false);
1687 TYPE_IS_PADDING_P (gnu_type) = 1;
1688 SET_TYPE_ADA_SIZE (gnu_type, bitsize_int (esize));
1690 relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY);
1693 /* Otherwise reset the alignment lest we computed it above. */
1699 case E_Floating_Point_Type:
1700 /* If this is a VAX floating-point type, use an integer of the proper
1701 size. All the operations will be handled with ASM statements. */
1702 if (Vax_Float (gnat_entity))
1704 gnu_type = make_signed_type (esize);
1705 TYPE_VAX_FLOATING_POINT_P (gnu_type) = 1;
1706 SET_TYPE_DIGITS_VALUE (gnu_type,
1707 UI_To_gnu (Digits_Value (gnat_entity),
1712 /* The type of the Low and High bounds can be our type if this is
1713 a type from Standard, so set them at the end of the function. */
1714 gnu_type = make_node (REAL_TYPE);
1715 TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize);
1716 layout_type (gnu_type);
1719 case E_Floating_Point_Subtype:
1720 if (Vax_Float (gnat_entity))
1722 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
1728 && Present (Ancestor_Subtype (gnat_entity))
1729 && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity))
1730 && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity))
1731 || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity))))
1732 gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity),
1735 gnu_type = make_node (REAL_TYPE);
1736 TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity));
1737 TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize);
1739 TYPE_MIN_VALUE (gnu_type)
1740 = convert (TREE_TYPE (gnu_type),
1741 elaborate_expression (Type_Low_Bound (gnat_entity),
1742 gnat_entity, get_identifier ("L"),
1744 Needs_Debug_Info (gnat_entity)));
1746 TYPE_MAX_VALUE (gnu_type)
1747 = convert (TREE_TYPE (gnu_type),
1748 elaborate_expression (Type_High_Bound (gnat_entity),
1749 gnat_entity, get_identifier ("U"),
1751 Needs_Debug_Info (gnat_entity)));
1753 /* One of the above calls might have caused us to be elaborated,
1754 so don't blow up if so. */
1755 if (present_gnu_tree (gnat_entity))
1757 maybe_present = true;
1761 layout_type (gnu_type);
1763 /* Inherit our alias set from what we're a subtype of, as for
1764 integer subtypes. */
1765 relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY);
1769 /* Array and String Types and Subtypes
1771 Unconstrained array types are represented by E_Array_Type and
1772 constrained array types are represented by E_Array_Subtype. There
1773 are no actual objects of an unconstrained array type; all we have
1774 are pointers to that type.
1776 The following fields are defined on array types and subtypes:
1778 Component_Type Component type of the array.
1779 Number_Dimensions Number of dimensions (an int).
1780 First_Index Type of first index. */
1785 tree gnu_template_fields = NULL_TREE;
1786 tree gnu_template_type = make_node (RECORD_TYPE);
1787 tree gnu_ptr_template = build_pointer_type (gnu_template_type);
1788 tree gnu_fat_type = make_node (RECORD_TYPE);
1789 int ndim = Number_Dimensions (gnat_entity);
1791 = (Convention (gnat_entity) == Convention_Fortran) ? ndim - 1 : 0;
1793 = (Convention (gnat_entity) == Convention_Fortran) ? - 1 : 1;
1795 tree *gnu_index_types = (tree *) alloca (ndim * sizeof (tree *));
1796 tree *gnu_temp_fields = (tree *) alloca (ndim * sizeof (tree *));
1797 tree gnu_comp_size = 0;
1798 tree gnu_max_size = size_one_node;
1799 tree gnu_max_size_unit;
1800 Entity_Id gnat_ind_subtype;
1801 Entity_Id gnat_ind_base_subtype;
1802 tree gnu_template_reference;
1805 TYPE_NAME (gnu_template_type)
1806 = create_concat_name (gnat_entity, "XUB");
1808 /* Make a node for the array. If we are not defining the array
1809 suppress expanding incomplete types. */
1810 gnu_type = make_node (UNCONSTRAINED_ARRAY_TYPE);
1813 defer_incomplete_level++, this_deferred = true;
1815 /* Build the fat pointer type. Use a "void *" object instead of
1816 a pointer to the array type since we don't have the array type
1817 yet (it will reference the fat pointer via the bounds). */
1818 tem = chainon (chainon (NULL_TREE,
1819 create_field_decl (get_identifier ("P_ARRAY"),
1821 gnu_fat_type, 0, 0, 0, 0)),
1822 create_field_decl (get_identifier ("P_BOUNDS"),
1824 gnu_fat_type, 0, 0, 0, 0));
1826 /* Make sure we can put this into a register. */
1827 TYPE_ALIGN (gnu_fat_type) = MIN (BIGGEST_ALIGNMENT, 2 * POINTER_SIZE);
1829 /* Do not finalize this record type since the types of its fields
1830 are still incomplete at this point. */
1831 finish_record_type (gnu_fat_type, tem, 0, true);
1832 TYPE_IS_FAT_POINTER_P (gnu_fat_type) = 1;
1834 /* Build a reference to the template from a PLACEHOLDER_EXPR that
1835 is the fat pointer. This will be used to access the individual
1836 fields once we build them. */
1837 tem = build3 (COMPONENT_REF, gnu_ptr_template,
1838 build0 (PLACEHOLDER_EXPR, gnu_fat_type),
1839 TREE_CHAIN (TYPE_FIELDS (gnu_fat_type)), NULL_TREE);
1840 gnu_template_reference
1841 = build_unary_op (INDIRECT_REF, gnu_template_type, tem);
1842 TREE_READONLY (gnu_template_reference) = 1;
1844 /* Now create the GCC type for each index and add the fields for
1845 that index to the template. */
1846 for (index = firstdim, gnat_ind_subtype = First_Index (gnat_entity),
1847 gnat_ind_base_subtype
1848 = First_Index (Implementation_Base_Type (gnat_entity));
1849 index < ndim && index >= 0;
1851 gnat_ind_subtype = Next_Index (gnat_ind_subtype),
1852 gnat_ind_base_subtype = Next_Index (gnat_ind_base_subtype))
1854 char field_name[10];
1855 tree gnu_ind_subtype
1856 = get_unpadded_type (Base_Type (Etype (gnat_ind_subtype)));
1857 tree gnu_base_subtype
1858 = get_unpadded_type (Etype (gnat_ind_base_subtype));
1860 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_subtype));
1862 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_subtype));
1863 tree gnu_min_field, gnu_max_field, gnu_min, gnu_max;
1865 /* Make the FIELD_DECLs for the minimum and maximum of this
1866 type and then make extractions of that field from the
1868 sprintf (field_name, "LB%d", index);
1869 gnu_min_field = create_field_decl (get_identifier (field_name),
1871 gnu_template_type, 0, 0, 0, 0);
1872 field_name[0] = 'U';
1873 gnu_max_field = create_field_decl (get_identifier (field_name),
1875 gnu_template_type, 0, 0, 0, 0);
1877 Sloc_to_locus (Sloc (gnat_entity),
1878 &DECL_SOURCE_LOCATION (gnu_min_field));
1879 Sloc_to_locus (Sloc (gnat_entity),
1880 &DECL_SOURCE_LOCATION (gnu_max_field));
1881 gnu_temp_fields[index] = chainon (gnu_min_field, gnu_max_field);
1883 /* We can't use build_component_ref here since the template
1884 type isn't complete yet. */
1885 gnu_min = build3 (COMPONENT_REF, gnu_ind_subtype,
1886 gnu_template_reference, gnu_min_field,
1888 gnu_max = build3 (COMPONENT_REF, gnu_ind_subtype,
1889 gnu_template_reference, gnu_max_field,
1891 TREE_READONLY (gnu_min) = TREE_READONLY (gnu_max) = 1;
1893 /* Make a range type with the new ranges, but using
1894 the Ada subtype. Then we convert to sizetype. */
1895 gnu_index_types[index]
1896 = create_index_type (convert (sizetype, gnu_min),
1897 convert (sizetype, gnu_max),
1898 build_range_type (gnu_ind_subtype,
1901 /* Update the maximum size of the array, in elements. */
1903 = size_binop (MULT_EXPR, gnu_max_size,
1904 size_binop (PLUS_EXPR, size_one_node,
1905 size_binop (MINUS_EXPR, gnu_base_max,
1908 TYPE_NAME (gnu_index_types[index])
1909 = create_concat_name (gnat_entity, field_name);
1912 for (index = 0; index < ndim; index++)
1914 = chainon (gnu_template_fields, gnu_temp_fields[index]);
1916 /* Install all the fields into the template. */
1917 finish_record_type (gnu_template_type, gnu_template_fields, 0, false);
1918 TYPE_READONLY (gnu_template_type) = 1;
1920 /* Now make the array of arrays and update the pointer to the array
1921 in the fat pointer. Note that it is the first field. */
1922 tem = gnat_to_gnu_type (Component_Type (gnat_entity));
1924 /* Try to get a smaller form of the component if needed. */
1925 if ((Is_Packed (gnat_entity)
1926 || Has_Component_Size_Clause (gnat_entity))
1927 && !Is_Bit_Packed_Array (gnat_entity)
1928 && !Has_Aliased_Components (gnat_entity)
1929 && !Strict_Alignment (Component_Type (gnat_entity))
1930 && TREE_CODE (tem) == RECORD_TYPE
1931 && !TYPE_IS_FAT_POINTER_P (tem)
1932 && host_integerp (TYPE_SIZE (tem), 1))
1933 tem = make_packable_type (tem, false);
1935 if (Has_Atomic_Components (gnat_entity))
1936 check_ok_for_atomic (tem, gnat_entity, true);
1938 /* Get and validate any specified Component_Size, but if Packed,
1939 ignore it since the front end will have taken care of it. */
1941 = validate_size (Component_Size (gnat_entity), tem,
1943 (Is_Bit_Packed_Array (gnat_entity)
1944 ? TYPE_DECL : VAR_DECL),
1945 true, Has_Component_Size_Clause (gnat_entity));
1947 /* If the component type is a RECORD_TYPE that has a self-referential
1948 size, use the maximum size. */
1949 if (!gnu_comp_size && TREE_CODE (tem) == RECORD_TYPE
1950 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (tem)))
1951 gnu_comp_size = max_size (TYPE_SIZE (tem), true);
1953 if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_entity))
1956 tem = make_type_from_size (tem, gnu_comp_size, false);
1958 tem = maybe_pad_type (tem, gnu_comp_size, 0, gnat_entity,
1959 "C_PAD", false, definition, true);
1960 /* If a padding record was made, declare it now since it will
1961 never be declared otherwise. This is necessary to ensure
1962 that its subtrees are properly marked. */
1963 if (tem != orig_tem)
1964 create_type_decl (TYPE_NAME (tem), tem, NULL, true,
1965 debug_info_p, gnat_entity);
1968 if (Has_Volatile_Components (gnat_entity))
1969 tem = build_qualified_type (tem,
1970 TYPE_QUALS (tem) | TYPE_QUAL_VOLATILE);
1972 /* If Component_Size is not already specified, annotate it with the
1973 size of the component. */
1974 if (Unknown_Component_Size (gnat_entity))
1975 Set_Component_Size (gnat_entity, annotate_value (TYPE_SIZE (tem)));
1977 gnu_max_size_unit = size_binop (MAX_EXPR, size_zero_node,
1978 size_binop (MULT_EXPR, gnu_max_size,
1979 TYPE_SIZE_UNIT (tem)));
1980 gnu_max_size = size_binop (MAX_EXPR, bitsize_zero_node,
1981 size_binop (MULT_EXPR,
1982 convert (bitsizetype,
1986 for (index = ndim - 1; index >= 0; index--)
1988 tem = build_array_type (tem, gnu_index_types[index]);
1989 TYPE_MULTI_ARRAY_P (tem) = (index > 0);
1990 if (array_type_has_nonaliased_component (gnat_entity, tem))
1991 TYPE_NONALIASED_COMPONENT (tem) = 1;
1994 /* If an alignment is specified, use it if valid. But ignore it for
1995 types that represent the unpacked base type for packed arrays. If
1996 the alignment was requested with an explicit user alignment clause,
1998 if (No (Packed_Array_Type (gnat_entity))
1999 && Known_Alignment (gnat_entity))
2001 gcc_assert (Present (Alignment (gnat_entity)));
2003 = validate_alignment (Alignment (gnat_entity), gnat_entity,
2005 if (Present (Alignment_Clause (gnat_entity)))
2006 TYPE_USER_ALIGN (tem) = 1;
2009 TYPE_CONVENTION_FORTRAN_P (tem)
2010 = (Convention (gnat_entity) == Convention_Fortran);
2011 TREE_TYPE (TYPE_FIELDS (gnu_fat_type)) = build_pointer_type (tem);
2013 /* The result type is an UNCONSTRAINED_ARRAY_TYPE that indicates the
2014 corresponding fat pointer. */
2015 TREE_TYPE (gnu_type) = TYPE_POINTER_TO (gnu_type)
2016 = TYPE_REFERENCE_TO (gnu_type) = gnu_fat_type;
2017 SET_TYPE_MODE (gnu_type, BLKmode);
2018 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (tem);
2019 SET_TYPE_UNCONSTRAINED_ARRAY (gnu_fat_type, gnu_type);
2021 /* If the maximum size doesn't overflow, use it. */
2022 if (TREE_CODE (gnu_max_size) == INTEGER_CST
2023 && !TREE_OVERFLOW (gnu_max_size))
2025 = size_binop (MIN_EXPR, gnu_max_size, TYPE_SIZE (tem));
2026 if (TREE_CODE (gnu_max_size_unit) == INTEGER_CST
2027 && !TREE_OVERFLOW (gnu_max_size_unit))
2028 TYPE_SIZE_UNIT (tem)
2029 = size_binop (MIN_EXPR, gnu_max_size_unit,
2030 TYPE_SIZE_UNIT (tem));
2032 create_type_decl (create_concat_name (gnat_entity, "XUA"),
2033 tem, NULL, !Comes_From_Source (gnat_entity),
2034 debug_info_p, gnat_entity);
2036 /* Give the fat pointer type a name. */
2037 create_type_decl (create_concat_name (gnat_entity, "XUP"),
2038 gnu_fat_type, NULL, true,
2039 debug_info_p, gnat_entity);
2041 /* Create the type to be used as what a thin pointer designates: an
2042 record type for the object and its template with the field offsets
2043 shifted to have the template at a negative offset. */
2044 tem = build_unc_object_type (gnu_template_type, tem,
2045 create_concat_name (gnat_entity, "XUT"));
2046 shift_unc_components_for_thin_pointers (tem);
2048 SET_TYPE_UNCONSTRAINED_ARRAY (tem, gnu_type);
2049 TYPE_OBJECT_RECORD_TYPE (gnu_type) = tem;
2051 /* Give the thin pointer type a name. */
2052 create_type_decl (create_concat_name (gnat_entity, "XUX"),
2053 build_pointer_type (tem), NULL, true,
2054 debug_info_p, gnat_entity);
2058 case E_String_Subtype:
2059 case E_Array_Subtype:
2061 /* This is the actual data type for array variables. Multidimensional
2062 arrays are implemented in the gnu tree as arrays of arrays. Note
2063 that for the moment arrays which have sparse enumeration subtypes as
2064 index components create sparse arrays, which is obviously space
2065 inefficient but so much easier to code for now.
2067 Also note that the subtype never refers to the unconstrained
2068 array type, which is somewhat at variance with Ada semantics.
2070 First check to see if this is simply a renaming of the array
2071 type. If so, the result is the array type. */
2073 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
2074 if (!Is_Constrained (gnat_entity))
2079 int array_dim = Number_Dimensions (gnat_entity);
2081 = ((Convention (gnat_entity) == Convention_Fortran)
2082 ? array_dim - 1 : 0);
2084 = (Convention (gnat_entity) == Convention_Fortran) ? -1 : 1;
2085 Entity_Id gnat_ind_subtype;
2086 Entity_Id gnat_ind_base_subtype;
2087 tree gnu_base_type = gnu_type;
2088 tree *gnu_index_type = (tree *) alloca (array_dim * sizeof (tree *));
2089 tree gnu_comp_size = NULL_TREE;
2090 tree gnu_max_size = size_one_node;
2091 tree gnu_max_size_unit;
2092 bool need_index_type_struct = false;
2093 bool max_overflow = false;
2095 /* First create the gnu types for each index. Create types for
2096 debugging information to point to the index types if the
2097 are not integer types, have variable bounds, or are
2098 wider than sizetype. */
2100 for (index = first_dim, gnat_ind_subtype = First_Index (gnat_entity),
2101 gnat_ind_base_subtype
2102 = First_Index (Implementation_Base_Type (gnat_entity));
2103 index < array_dim && index >= 0;
2105 gnat_ind_subtype = Next_Index (gnat_ind_subtype),
2106 gnat_ind_base_subtype = Next_Index (gnat_ind_base_subtype))
2108 tree gnu_index_subtype
2109 = get_unpadded_type (Etype (gnat_ind_subtype));
2111 = convert (sizetype, TYPE_MIN_VALUE (gnu_index_subtype));
2113 = convert (sizetype, TYPE_MAX_VALUE (gnu_index_subtype));
2114 tree gnu_base_subtype
2115 = get_unpadded_type (Etype (gnat_ind_base_subtype));
2117 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_subtype));
2119 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_subtype));
2120 tree gnu_base_type = get_base_type (gnu_base_subtype);
2121 tree gnu_base_base_min
2122 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_type));
2123 tree gnu_base_base_max
2124 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_type));
2128 /* If the minimum and maximum values both overflow in
2129 SIZETYPE, but the difference in the original type
2130 does not overflow in SIZETYPE, ignore the overflow
2132 if ((TYPE_PRECISION (gnu_index_subtype)
2133 > TYPE_PRECISION (sizetype)
2134 || TYPE_UNSIGNED (gnu_index_subtype)
2135 != TYPE_UNSIGNED (sizetype))
2136 && TREE_CODE (gnu_min) == INTEGER_CST
2137 && TREE_CODE (gnu_max) == INTEGER_CST
2138 && TREE_OVERFLOW (gnu_min) && TREE_OVERFLOW (gnu_max)
2140 (fold_build2 (MINUS_EXPR, gnu_index_subtype,
2141 TYPE_MAX_VALUE (gnu_index_subtype),
2142 TYPE_MIN_VALUE (gnu_index_subtype)))))
2144 TREE_OVERFLOW (gnu_min) = 0;
2145 TREE_OVERFLOW (gnu_max) = 0;
2148 /* Similarly, if the range is null, use bounds of 1..0 for
2149 the sizetype bounds. */
2150 else if ((TYPE_PRECISION (gnu_index_subtype)
2151 > TYPE_PRECISION (sizetype)
2152 || TYPE_UNSIGNED (gnu_index_subtype)
2153 != TYPE_UNSIGNED (sizetype))
2154 && TREE_CODE (gnu_min) == INTEGER_CST
2155 && TREE_CODE (gnu_max) == INTEGER_CST
2156 && (TREE_OVERFLOW (gnu_min) || TREE_OVERFLOW (gnu_max))
2157 && tree_int_cst_lt (TYPE_MAX_VALUE (gnu_index_subtype),
2158 TYPE_MIN_VALUE (gnu_index_subtype)))
2159 gnu_min = size_one_node, gnu_max = size_zero_node;
2161 /* Now compute the size of this bound. We need to provide
2162 GCC with an upper bound to use but have to deal with the
2163 "superflat" case. There are three ways to do this. If we
2164 can prove that the array can never be superflat, we can
2165 just use the high bound of the index subtype. If we can
2166 prove that the low bound minus one can't overflow, we
2167 can do this as MAX (hb, lb - 1). Otherwise, we have to use
2168 the expression hb >= lb ? hb : lb - 1. */
2169 gnu_high = size_binop (MINUS_EXPR, gnu_min, size_one_node);
2171 /* See if the base array type is already flat. If it is, we
2172 are probably compiling an ACVC test, but it will cause the
2173 code below to malfunction if we don't handle it specially. */
2174 if (TREE_CODE (gnu_base_min) == INTEGER_CST
2175 && TREE_CODE (gnu_base_max) == INTEGER_CST
2176 && !TREE_OVERFLOW (gnu_base_min)
2177 && !TREE_OVERFLOW (gnu_base_max)
2178 && tree_int_cst_lt (gnu_base_max, gnu_base_min))
2179 gnu_high = size_zero_node, gnu_min = size_one_node;
2181 /* If gnu_high is now an integer which overflowed, the array
2182 cannot be superflat. */
2183 else if (TREE_CODE (gnu_high) == INTEGER_CST
2184 && TREE_OVERFLOW (gnu_high))
2186 else if (TYPE_UNSIGNED (gnu_base_subtype)
2187 || TREE_CODE (gnu_high) == INTEGER_CST)
2188 gnu_high = size_binop (MAX_EXPR, gnu_max, gnu_high);
2192 (sizetype, build_binary_op (GE_EXPR, integer_type_node,
2196 gnu_index_type[index]
2197 = create_index_type (gnu_min, gnu_high, gnu_index_subtype,
2200 /* Also compute the maximum size of the array. Here we
2201 see if any constraint on the index type of the base type
2202 can be used in the case of self-referential bound on
2203 the index type of the subtype. We look for a non-"infinite"
2204 and non-self-referential bound from any type involved and
2205 handle each bound separately. */
2207 if ((TREE_CODE (gnu_min) == INTEGER_CST
2208 && !TREE_OVERFLOW (gnu_min)
2209 && !operand_equal_p (gnu_min, gnu_base_base_min, 0))
2210 || !CONTAINS_PLACEHOLDER_P (gnu_min)
2211 || !(TREE_CODE (gnu_base_min) == INTEGER_CST
2212 && !TREE_OVERFLOW (gnu_base_min)))
2213 gnu_base_min = gnu_min;
2215 if ((TREE_CODE (gnu_max) == INTEGER_CST
2216 && !TREE_OVERFLOW (gnu_max)
2217 && !operand_equal_p (gnu_max, gnu_base_base_max, 0))
2218 || !CONTAINS_PLACEHOLDER_P (gnu_max)
2219 || !(TREE_CODE (gnu_base_max) == INTEGER_CST
2220 && !TREE_OVERFLOW (gnu_base_max)))
2221 gnu_base_max = gnu_max;
2223 if ((TREE_CODE (gnu_base_min) == INTEGER_CST
2224 && TREE_OVERFLOW (gnu_base_min))
2225 || operand_equal_p (gnu_base_min, gnu_base_base_min, 0)
2226 || (TREE_CODE (gnu_base_max) == INTEGER_CST
2227 && TREE_OVERFLOW (gnu_base_max))
2228 || operand_equal_p (gnu_base_max, gnu_base_base_max, 0))
2229 max_overflow = true;
2231 gnu_base_min = size_binop (MAX_EXPR, gnu_base_min, gnu_min);
2232 gnu_base_max = size_binop (MIN_EXPR, gnu_base_max, gnu_max);
2235 = size_binop (MAX_EXPR,
2236 size_binop (PLUS_EXPR, size_one_node,
2237 size_binop (MINUS_EXPR, gnu_base_max,
2241 if (TREE_CODE (gnu_this_max) == INTEGER_CST
2242 && TREE_OVERFLOW (gnu_this_max))
2243 max_overflow = true;
2246 = size_binop (MULT_EXPR, gnu_max_size, gnu_this_max);
2248 if (!integer_onep (TYPE_MIN_VALUE (gnu_index_subtype))
2249 || (TREE_CODE (TYPE_MAX_VALUE (gnu_index_subtype))
2251 || TREE_CODE (gnu_index_subtype) != INTEGER_TYPE
2252 || (TREE_TYPE (gnu_index_subtype)
2253 && (TREE_CODE (TREE_TYPE (gnu_index_subtype))
2255 || TYPE_BIASED_REPRESENTATION_P (gnu_index_subtype)
2256 || (TYPE_PRECISION (gnu_index_subtype)
2257 > TYPE_PRECISION (sizetype)))
2258 need_index_type_struct = true;
2261 /* Then flatten: create the array of arrays. For an array type
2262 used to implement a packed array, get the component type from
2263 the original array type since the representation clauses that
2264 can affect it are on the latter. */
2265 if (Is_Packed_Array_Type (gnat_entity)
2266 && !Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
2268 gnu_type = gnat_to_gnu_type (Original_Array_Type (gnat_entity));
2269 for (index = array_dim - 1; index >= 0; index--)
2270 gnu_type = TREE_TYPE (gnu_type);
2272 /* One of the above calls might have caused us to be elaborated,
2273 so don't blow up if so. */
2274 if (present_gnu_tree (gnat_entity))
2276 maybe_present = true;
2282 gnu_type = gnat_to_gnu_type (Component_Type (gnat_entity));
2284 /* One of the above calls might have caused us to be elaborated,
2285 so don't blow up if so. */
2286 if (present_gnu_tree (gnat_entity))
2288 maybe_present = true;
2292 /* Try to get a smaller form of the component if needed. */
2293 if ((Is_Packed (gnat_entity)
2294 || Has_Component_Size_Clause (gnat_entity))
2295 && !Is_Bit_Packed_Array (gnat_entity)
2296 && !Has_Aliased_Components (gnat_entity)
2297 && !Strict_Alignment (Component_Type (gnat_entity))
2298 && TREE_CODE (gnu_type) == RECORD_TYPE
2299 && !TYPE_IS_FAT_POINTER_P (gnu_type)
2300 && host_integerp (TYPE_SIZE (gnu_type), 1))
2301 gnu_type = make_packable_type (gnu_type, false);
2303 /* Get and validate any specified Component_Size, but if Packed,
2304 ignore it since the front end will have taken care of it. */
2306 = validate_size (Component_Size (gnat_entity), gnu_type,
2308 (Is_Bit_Packed_Array (gnat_entity)
2309 ? TYPE_DECL : VAR_DECL), true,
2310 Has_Component_Size_Clause (gnat_entity));
2312 /* If the component type is a RECORD_TYPE that has a
2313 self-referential size, use the maximum size. */
2315 && TREE_CODE (gnu_type) == RECORD_TYPE
2316 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
2317 gnu_comp_size = max_size (TYPE_SIZE (gnu_type), true);
2319 if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_entity))
2323 = make_type_from_size (gnu_type, gnu_comp_size, false);
2324 orig_gnu_type = gnu_type;
2325 gnu_type = maybe_pad_type (gnu_type, gnu_comp_size, 0,
2326 gnat_entity, "C_PAD", false,
2328 /* If a padding record was made, declare it now since it
2329 will never be declared otherwise. This is necessary
2330 to ensure that its subtrees are properly marked. */
2331 if (gnu_type != orig_gnu_type)
2332 create_type_decl (TYPE_NAME (gnu_type), gnu_type, NULL,
2333 true, debug_info_p, gnat_entity);
2336 if (Has_Volatile_Components (Base_Type (gnat_entity)))
2337 gnu_type = build_qualified_type (gnu_type,
2338 (TYPE_QUALS (gnu_type)
2339 | TYPE_QUAL_VOLATILE));
2342 gnu_max_size_unit = size_binop (MULT_EXPR, gnu_max_size,
2343 TYPE_SIZE_UNIT (gnu_type));
2344 gnu_max_size = size_binop (MULT_EXPR,
2345 convert (bitsizetype, gnu_max_size),
2346 TYPE_SIZE (gnu_type));
2348 for (index = array_dim - 1; index >= 0; index --)
2350 gnu_type = build_array_type (gnu_type, gnu_index_type[index]);
2351 TYPE_MULTI_ARRAY_P (gnu_type) = (index > 0);
2352 if (array_type_has_nonaliased_component (gnat_entity, gnu_type))
2353 TYPE_NONALIASED_COMPONENT (gnu_type) = 1;
2356 /* Attach the TYPE_STUB_DECL in case we have a parallel type. */
2357 if (need_index_type_struct)
2358 TYPE_STUB_DECL (gnu_type)
2359 = create_type_stub_decl (gnu_entity_id, gnu_type);
2361 /* If we are at file level and this is a multi-dimensional array, we
2362 need to make a variable corresponding to the stride of the
2363 inner dimensions. */
2364 if (global_bindings_p () && array_dim > 1)
2366 tree gnu_str_name = get_identifier ("ST");
2369 for (gnu_arr_type = TREE_TYPE (gnu_type);
2370 TREE_CODE (gnu_arr_type) == ARRAY_TYPE;
2371 gnu_arr_type = TREE_TYPE (gnu_arr_type),
2372 gnu_str_name = concat_id_with_name (gnu_str_name, "ST"))
2374 tree eltype = TREE_TYPE (gnu_arr_type);
2376 TYPE_SIZE (gnu_arr_type)
2377 = elaborate_expression_1 (gnat_entity, gnat_entity,
2378 TYPE_SIZE (gnu_arr_type),
2379 gnu_str_name, definition, 0);
2381 /* ??? For now, store the size as a multiple of the
2382 alignment of the element type in bytes so that we
2383 can see the alignment from the tree. */
2384 TYPE_SIZE_UNIT (gnu_arr_type)
2386 (MULT_EXPR, sizetype,
2387 elaborate_expression_1
2388 (gnat_entity, gnat_entity,
2389 build_binary_op (EXACT_DIV_EXPR, sizetype,
2390 TYPE_SIZE_UNIT (gnu_arr_type),
2391 size_int (TYPE_ALIGN (eltype)
2393 concat_id_with_name (gnu_str_name, "A_U"),
2395 size_int (TYPE_ALIGN (eltype) / BITS_PER_UNIT));
2397 /* ??? create_type_decl is not invoked on the inner types so
2398 the MULT_EXPR node built above will never be marked. */
2399 mark_visited (&TYPE_SIZE_UNIT (gnu_arr_type));
2403 /* If we need to write out a record type giving the names of
2404 the bounds, do it now. Make sure to reference the index
2405 types themselves, not just their names, as the debugger
2406 may fall back on them in some cases. */
2407 if (need_index_type_struct && debug_info_p)
2409 tree gnu_bound_rec = make_node (RECORD_TYPE);
2410 tree gnu_field_list = NULL_TREE;
2413 TYPE_NAME (gnu_bound_rec)
2414 = create_concat_name (gnat_entity, "XA");
2416 for (index = array_dim - 1; index >= 0; index--)
2418 tree gnu_index = TYPE_INDEX_TYPE (gnu_index_type[index]);
2419 tree gnu_index_name = TYPE_NAME (gnu_index);
2421 if (TREE_CODE (gnu_index_name) == TYPE_DECL)
2422 gnu_index_name = DECL_NAME (gnu_index_name);
2424 gnu_field = create_field_decl (gnu_index_name, gnu_index,
2426 0, NULL_TREE, NULL_TREE, 0);
2427 TREE_CHAIN (gnu_field) = gnu_field_list;
2428 gnu_field_list = gnu_field;
2431 finish_record_type (gnu_bound_rec, gnu_field_list, 0, false);
2432 add_parallel_type (TYPE_STUB_DECL (gnu_type), gnu_bound_rec);
2435 TYPE_CONVENTION_FORTRAN_P (gnu_type)
2436 = (Convention (gnat_entity) == Convention_Fortran);
2437 TYPE_PACKED_ARRAY_TYPE_P (gnu_type)
2438 = (Is_Packed_Array_Type (gnat_entity)
2439 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)));
2441 /* If our size depends on a placeholder and the maximum size doesn't
2442 overflow, use it. */
2443 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
2444 && !(TREE_CODE (gnu_max_size) == INTEGER_CST
2445 && TREE_OVERFLOW (gnu_max_size))
2446 && !(TREE_CODE (gnu_max_size_unit) == INTEGER_CST
2447 && TREE_OVERFLOW (gnu_max_size_unit))
2450 TYPE_SIZE (gnu_type) = size_binop (MIN_EXPR, gnu_max_size,
2451 TYPE_SIZE (gnu_type));
2452 TYPE_SIZE_UNIT (gnu_type)
2453 = size_binop (MIN_EXPR, gnu_max_size_unit,
2454 TYPE_SIZE_UNIT (gnu_type));
2457 /* Set our alias set to that of our base type. This gives all
2458 array subtypes the same alias set. */
2459 relate_alias_sets (gnu_type, gnu_base_type, ALIAS_SET_COPY);
2462 /* If this is a packed type, make this type the same as the packed
2463 array type, but do some adjusting in the type first. */
2464 if (Present (Packed_Array_Type (gnat_entity)))
2466 Entity_Id gnat_index;
2467 tree gnu_inner_type;
2469 /* First finish the type we had been making so that we output
2470 debugging information for it. */
2472 = build_qualified_type (gnu_type,
2473 (TYPE_QUALS (gnu_type)
2474 | (TYPE_QUAL_VOLATILE
2475 * Treat_As_Volatile (gnat_entity))));
2477 /* Make it artificial only if the base type was artificial as well.
2478 That's sort of "morally" true and will make it possible for the
2479 debugger to look it up by name in DWARF more easily. */
2481 = create_type_decl (gnu_entity_id, gnu_type, attr_list,
2482 !Comes_From_Source (gnat_entity)
2483 && !Comes_From_Source (Etype (gnat_entity)),
2484 debug_info_p, gnat_entity);
2486 /* Save it as our equivalent in case the call below elaborates
2488 save_gnu_tree (gnat_entity, gnu_decl, false);
2490 gnu_decl = gnat_to_gnu_entity (Packed_Array_Type (gnat_entity),
2492 this_made_decl = true;
2493 gnu_type = TREE_TYPE (gnu_decl);
2494 save_gnu_tree (gnat_entity, NULL_TREE, false);
2496 gnu_inner_type = gnu_type;
2497 while (TREE_CODE (gnu_inner_type) == RECORD_TYPE
2498 && (TYPE_JUSTIFIED_MODULAR_P (gnu_inner_type)
2499 || TYPE_IS_PADDING_P (gnu_inner_type)))
2500 gnu_inner_type = TREE_TYPE (TYPE_FIELDS (gnu_inner_type));
2502 /* We need to point the type we just made to our index type so
2503 the actual bounds can be put into a template. */
2505 if ((TREE_CODE (gnu_inner_type) == ARRAY_TYPE
2506 && !TYPE_ACTUAL_BOUNDS (gnu_inner_type))
2507 || (TREE_CODE (gnu_inner_type) == INTEGER_TYPE
2508 && !TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner_type)))
2510 if (TREE_CODE (gnu_inner_type) == INTEGER_TYPE)
2512 /* The TYPE_ACTUAL_BOUNDS field is also used for the modulus.
2513 If it is, we need to make another type. */
2514 if (TYPE_MODULAR_P (gnu_inner_type))
2518 gnu_subtype = make_node (INTEGER_TYPE);
2520 TREE_TYPE (gnu_subtype) = gnu_inner_type;
2521 TYPE_MIN_VALUE (gnu_subtype)
2522 = TYPE_MIN_VALUE (gnu_inner_type);
2523 TYPE_MAX_VALUE (gnu_subtype)
2524 = TYPE_MAX_VALUE (gnu_inner_type);
2525 TYPE_PRECISION (gnu_subtype)
2526 = TYPE_PRECISION (gnu_inner_type);
2527 TYPE_UNSIGNED (gnu_subtype)
2528 = TYPE_UNSIGNED (gnu_inner_type);
2529 TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1;
2530 layout_type (gnu_subtype);
2532 gnu_inner_type = gnu_subtype;
2535 TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner_type) = 1;
2538 SET_TYPE_ACTUAL_BOUNDS (gnu_inner_type, NULL_TREE);
2540 for (gnat_index = First_Index (gnat_entity);
2541 Present (gnat_index); gnat_index = Next_Index (gnat_index))
2542 SET_TYPE_ACTUAL_BOUNDS
2544 tree_cons (NULL_TREE,
2545 get_unpadded_type (Etype (gnat_index)),
2546 TYPE_ACTUAL_BOUNDS (gnu_inner_type)));
2548 if (Convention (gnat_entity) != Convention_Fortran)
2549 SET_TYPE_ACTUAL_BOUNDS
2551 nreverse (TYPE_ACTUAL_BOUNDS (gnu_inner_type)));
2553 if (TREE_CODE (gnu_type) == RECORD_TYPE
2554 && TYPE_JUSTIFIED_MODULAR_P (gnu_type))
2555 TREE_TYPE (TYPE_FIELDS (gnu_type)) = gnu_inner_type;
2559 /* Abort if packed array with no packed array type field set. */
2561 gcc_assert (!Is_Packed (gnat_entity));
2565 case E_String_Literal_Subtype:
2566 /* Create the type for a string literal. */
2568 Entity_Id gnat_full_type
2569 = (IN (Ekind (Etype (gnat_entity)), Private_Kind)
2570 && Present (Full_View (Etype (gnat_entity)))
2571 ? Full_View (Etype (gnat_entity)) : Etype (gnat_entity));
2572 tree gnu_string_type = get_unpadded_type (gnat_full_type);
2573 tree gnu_string_array_type
2574 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_string_type))));
2575 tree gnu_string_index_type
2576 = get_base_type (TREE_TYPE (TYPE_INDEX_TYPE
2577 (TYPE_DOMAIN (gnu_string_array_type))));
2578 tree gnu_lower_bound
2579 = convert (gnu_string_index_type,
2580 gnat_to_gnu (String_Literal_Low_Bound (gnat_entity)));
2581 int length = UI_To_Int (String_Literal_Length (gnat_entity));
2582 tree gnu_length = ssize_int (length - 1);
2583 tree gnu_upper_bound
2584 = build_binary_op (PLUS_EXPR, gnu_string_index_type,
2586 convert (gnu_string_index_type, gnu_length));
2588 = build_range_type (gnu_string_index_type,
2589 gnu_lower_bound, gnu_upper_bound);
2591 = create_index_type (convert (sizetype,
2592 TYPE_MIN_VALUE (gnu_range_type)),
2594 TYPE_MAX_VALUE (gnu_range_type)),
2595 gnu_range_type, gnat_entity);
2598 = build_array_type (gnat_to_gnu_type (Component_Type (gnat_entity)),
2600 if (array_type_has_nonaliased_component (gnat_entity, gnu_type))
2601 TYPE_NONALIASED_COMPONENT (gnu_type) = 1;
2602 relate_alias_sets (gnu_type, gnu_string_type, ALIAS_SET_COPY);
2606 /* Record Types and Subtypes
2608 The following fields are defined on record types:
2610 Has_Discriminants True if the record has discriminants
2611 First_Discriminant Points to head of list of discriminants
2612 First_Entity Points to head of list of fields
2613 Is_Tagged_Type True if the record is tagged
2615 Implementation of Ada records and discriminated records:
2617 A record type definition is transformed into the equivalent of a C
2618 struct definition. The fields that are the discriminants which are
2619 found in the Full_Type_Declaration node and the elements of the
2620 Component_List found in the Record_Type_Definition node. The
2621 Component_List can be a recursive structure since each Variant of
2622 the Variant_Part of the Component_List has a Component_List.
2624 Processing of a record type definition comprises starting the list of
2625 field declarations here from the discriminants and the calling the
2626 function components_to_record to add the rest of the fields from the
2627 component list and return the gnu type node. The function
2628 components_to_record will call itself recursively as it traverses
2632 if (Has_Complex_Representation (gnat_entity))
2635 = build_complex_type
2637 (Etype (Defining_Entity
2638 (First (Component_Items
2641 (Declaration_Node (gnat_entity)))))))));
2647 Node_Id full_definition = Declaration_Node (gnat_entity);
2648 Node_Id record_definition = Type_Definition (full_definition);
2649 Entity_Id gnat_field;
2651 tree gnu_field_list = NULL_TREE;
2652 tree gnu_get_parent;
2653 /* Set PACKED in keeping with gnat_to_gnu_field. */
2655 = Is_Packed (gnat_entity)
2657 : Component_Alignment (gnat_entity) == Calign_Storage_Unit
2659 : (Known_Alignment (gnat_entity)
2660 || (Strict_Alignment (gnat_entity)
2661 && Known_Static_Esize (gnat_entity)))
2664 bool has_rep = Has_Specified_Layout (gnat_entity);
2665 bool all_rep = has_rep;
2667 = (Is_Tagged_Type (gnat_entity)
2668 && Nkind (record_definition) == N_Derived_Type_Definition);
2670 /* See if all fields have a rep clause. Stop when we find one
2672 for (gnat_field = First_Entity (gnat_entity);
2673 Present (gnat_field) && all_rep;
2674 gnat_field = Next_Entity (gnat_field))
2675 if ((Ekind (gnat_field) == E_Component
2676 || Ekind (gnat_field) == E_Discriminant)
2677 && No (Component_Clause (gnat_field)))
2680 /* If this is a record extension, go a level further to find the
2681 record definition. Also, verify we have a Parent_Subtype. */
2684 if (!type_annotate_only
2685 || Present (Record_Extension_Part (record_definition)))
2686 record_definition = Record_Extension_Part (record_definition);
2688 gcc_assert (type_annotate_only
2689 || Present (Parent_Subtype (gnat_entity)));
2692 /* Make a node for the record. If we are not defining the record,
2693 suppress expanding incomplete types. */
2694 gnu_type = make_node (tree_code_for_record_type (gnat_entity));
2695 TYPE_NAME (gnu_type) = gnu_entity_id;
2696 TYPE_PACKED (gnu_type) = (packed != 0) || has_rep;
2699 defer_incomplete_level++, this_deferred = true;
2701 /* If both a size and rep clause was specified, put the size in
2702 the record type now so that it can get the proper mode. */
2703 if (has_rep && Known_Esize (gnat_entity))
2704 TYPE_SIZE (gnu_type) = UI_To_gnu (Esize (gnat_entity), sizetype);
2706 /* Always set the alignment here so that it can be used to
2707 set the mode, if it is making the alignment stricter. If
2708 it is invalid, it will be checked again below. If this is to
2709 be Atomic, choose a default alignment of a word unless we know
2710 the size and it's smaller. */
2711 if (Known_Alignment (gnat_entity))
2712 TYPE_ALIGN (gnu_type)
2713 = validate_alignment (Alignment (gnat_entity), gnat_entity, 0);
2714 else if (Is_Atomic (gnat_entity))
2715 TYPE_ALIGN (gnu_type)
2716 = esize >= BITS_PER_WORD ? BITS_PER_WORD : ceil_alignment (esize);
2717 /* If a type needs strict alignment, the minimum size will be the
2718 type size instead of the RM size (see validate_size). Cap the
2719 alignment, lest it causes this type size to become too large. */
2720 else if (Strict_Alignment (gnat_entity)
2721 && Known_Static_Esize (gnat_entity))
2723 unsigned int raw_size = UI_To_Int (Esize (gnat_entity));
2724 unsigned int raw_align = raw_size & -raw_size;
2725 if (raw_align < BIGGEST_ALIGNMENT)
2726 TYPE_ALIGN (gnu_type) = raw_align;
2729 TYPE_ALIGN (gnu_type) = 0;
2731 /* If we have a Parent_Subtype, make a field for the parent. If
2732 this record has rep clauses, force the position to zero. */
2733 if (Present (Parent_Subtype (gnat_entity)))
2735 Entity_Id gnat_parent = Parent_Subtype (gnat_entity);
2738 /* A major complexity here is that the parent subtype will
2739 reference our discriminants in its Discriminant_Constraint
2740 list. But those must reference the parent component of this
2741 record which is of the parent subtype we have not built yet!
2742 To break the circle we first build a dummy COMPONENT_REF which
2743 represents the "get to the parent" operation and initialize
2744 each of those discriminants to a COMPONENT_REF of the above
2745 dummy parent referencing the corresponding discriminant of the
2746 base type of the parent subtype. */
2747 gnu_get_parent = build3 (COMPONENT_REF, void_type_node,
2748 build0 (PLACEHOLDER_EXPR, gnu_type),
2749 build_decl (FIELD_DECL, NULL_TREE,
2753 if (Has_Discriminants (gnat_entity))
2754 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2755 Present (gnat_field);
2756 gnat_field = Next_Stored_Discriminant (gnat_field))
2757 if (Present (Corresponding_Discriminant (gnat_field)))
2760 build3 (COMPONENT_REF,
2761 get_unpadded_type (Etype (gnat_field)),
2763 gnat_to_gnu_field_decl (Corresponding_Discriminant
2768 /* Then we build the parent subtype. If it has discriminants but
2769 the type itself has unknown discriminants, this means that it
2770 doesn't contain information about how the discriminants are
2771 derived from those of the ancestor type, so it cannot be used
2772 directly. Instead it is built by cloning the parent subtype
2773 of the underlying record view of the type, for which the above
2774 derivation of discriminants has been made explicit. */
2775 if (Has_Discriminants (gnat_parent)
2776 && Has_Unknown_Discriminants (gnat_entity))
2778 Entity_Id gnat_uview = Underlying_Record_View (gnat_entity);
2780 /* If we are defining the type, the underlying record
2781 view must already have been elaborated at this point.
2782 Otherwise do it now as its parent subtype cannot be
2783 technically elaborated on its own. */
2785 gcc_assert (present_gnu_tree (gnat_uview));
2787 gnat_to_gnu_entity (gnat_uview, NULL_TREE, 0);
2789 gnu_parent = gnat_to_gnu_type (Parent_Subtype (gnat_uview));
2791 /* Substitute the "get to the parent" of the type for that
2792 of its underlying record view in the cloned type. */
2793 for (gnat_field = First_Stored_Discriminant (gnat_uview);
2794 Present (gnat_field);
2795 gnat_field = Next_Stored_Discriminant (gnat_field))
2796 if (Present (Corresponding_Discriminant (gnat_field)))
2798 tree gnu_field = gnat_to_gnu_field_decl (gnat_field);
2800 = build3 (COMPONENT_REF, TREE_TYPE (gnu_field),
2801 gnu_get_parent, gnu_field, NULL_TREE);
2803 = substitute_in_type (gnu_parent, gnu_field, gnu_ref);
2807 gnu_parent = gnat_to_gnu_type (gnat_parent);
2809 /* Finally we fix up both kinds of twisted COMPONENT_REF we have
2810 initially built. The discriminants must reference the fields
2811 of the parent subtype and not those of its base type for the
2812 placeholder machinery to properly work. */
2813 if (Has_Discriminants (gnat_entity))
2814 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2815 Present (gnat_field);
2816 gnat_field = Next_Stored_Discriminant (gnat_field))
2817 if (Present (Corresponding_Discriminant (gnat_field)))
2819 Entity_Id field = Empty;
2820 for (field = First_Stored_Discriminant (gnat_parent);
2822 field = Next_Stored_Discriminant (field))
2823 if (same_discriminant_p (gnat_field, field))
2825 gcc_assert (Present (field));
2826 TREE_OPERAND (get_gnu_tree (gnat_field), 1)
2827 = gnat_to_gnu_field_decl (field);
2830 /* The "get to the parent" COMPONENT_REF must be given its
2832 TREE_TYPE (gnu_get_parent) = gnu_parent;
2834 /* ...and reference the _parent field of this record. */
2836 = create_field_decl (get_identifier
2837 (Get_Name_String (Name_uParent)),
2838 gnu_parent, gnu_type, 0,
2839 has_rep ? TYPE_SIZE (gnu_parent) : 0,
2840 has_rep ? bitsize_zero_node : 0, 1);
2841 DECL_INTERNAL_P (gnu_field_list) = 1;
2842 TREE_OPERAND (gnu_get_parent, 1) = gnu_field_list;
2845 /* Make the fields for the discriminants and put them into the record
2846 unless it's an Unchecked_Union. */
2847 if (Has_Discriminants (gnat_entity))
2848 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2849 Present (gnat_field);
2850 gnat_field = Next_Stored_Discriminant (gnat_field))
2852 /* If this is a record extension and this discriminant
2853 is the renaming of another discriminant, we've already
2854 handled the discriminant above. */
2855 if (Present (Parent_Subtype (gnat_entity))
2856 && Present (Corresponding_Discriminant (gnat_field)))
2860 = gnat_to_gnu_field (gnat_field, gnu_type, packed, definition);
2862 /* Make an expression using a PLACEHOLDER_EXPR from the
2863 FIELD_DECL node just created and link that with the
2864 corresponding GNAT defining identifier. Then add to the
2866 save_gnu_tree (gnat_field,
2867 build3 (COMPONENT_REF, TREE_TYPE (gnu_field),
2868 build0 (PLACEHOLDER_EXPR,
2869 DECL_CONTEXT (gnu_field)),
2870 gnu_field, NULL_TREE),
2873 if (!Is_Unchecked_Union (gnat_entity))
2875 TREE_CHAIN (gnu_field) = gnu_field_list;
2876 gnu_field_list = gnu_field;
2880 /* Put the discriminants into the record (backwards), so we can
2881 know the appropriate discriminant to use for the names of the
2883 TYPE_FIELDS (gnu_type) = gnu_field_list;
2885 /* Add the listed fields into the record and finish it up. */
2886 components_to_record (gnu_type, Component_List (record_definition),
2887 gnu_field_list, packed, definition, NULL,
2888 false, all_rep, false,
2889 Is_Unchecked_Union (gnat_entity));
2891 /* We used to remove the associations of the discriminants and
2892 _Parent for validity checking, but we may need them if there's
2893 Freeze_Node for a subtype used in this record. */
2894 TYPE_VOLATILE (gnu_type) = Treat_As_Volatile (gnat_entity);
2895 TYPE_BY_REFERENCE_P (gnu_type) = Is_By_Reference_Type (gnat_entity);
2897 /* If it is a tagged record force the type to BLKmode to insure
2898 that these objects will always be placed in memory. Do the
2899 same thing for limited record types. */
2900 if (Is_Tagged_Type (gnat_entity) || Is_Limited_Record (gnat_entity))
2901 SET_TYPE_MODE (gnu_type, BLKmode);
2903 /* Fill in locations of fields. */
2904 annotate_rep (gnat_entity, gnu_type);
2906 /* If there are any entities in the chain corresponding to
2907 components that we did not elaborate, ensure we elaborate their
2908 types if they are Itypes. */
2909 for (gnat_temp = First_Entity (gnat_entity);
2910 Present (gnat_temp); gnat_temp = Next_Entity (gnat_temp))
2911 if ((Ekind (gnat_temp) == E_Component
2912 || Ekind (gnat_temp) == E_Discriminant)
2913 && Is_Itype (Etype (gnat_temp))
2914 && !present_gnu_tree (gnat_temp))
2915 gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0);
2919 case E_Class_Wide_Subtype:
2920 /* If an equivalent type is present, that is what we should use.
2921 Otherwise, fall through to handle this like a record subtype
2922 since it may have constraints. */
2923 if (gnat_equiv_type != gnat_entity)
2925 gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0);
2926 maybe_present = true;
2930 /* ... fall through ... */
2932 case E_Record_Subtype:
2934 /* If Cloned_Subtype is Present it means this record subtype has
2935 identical layout to that type or subtype and we should use
2936 that GCC type for this one. The front end guarantees that
2937 the component list is shared. */
2938 if (Present (Cloned_Subtype (gnat_entity)))
2940 gnu_decl = gnat_to_gnu_entity (Cloned_Subtype (gnat_entity),
2942 maybe_present = true;
2945 /* Otherwise, first ensure the base type is elaborated. Then, if we are
2946 changing the type, make a new type with each field having the
2947 type of the field in the new subtype but having the position
2948 computed by transforming every discriminant reference according
2949 to the constraints. We don't see any difference between
2950 private and nonprivate type here since derivations from types should
2951 have been deferred until the completion of the private type. */
2954 Entity_Id gnat_base_type = Implementation_Base_Type (gnat_entity);
2959 defer_incomplete_level++, this_deferred = true;
2961 /* Get the base type initially for its alignment and sizes. But
2962 if it is a padded type, we do all the other work with the
2964 gnu_base_type = gnat_to_gnu_type (gnat_base_type);
2966 if (TREE_CODE (gnu_base_type) == RECORD_TYPE
2967 && TYPE_IS_PADDING_P (gnu_base_type))
2968 gnu_type = gnu_orig_type = TREE_TYPE (TYPE_FIELDS (gnu_base_type));
2970 gnu_type = gnu_orig_type = gnu_base_type;
2972 if (present_gnu_tree (gnat_entity))
2974 maybe_present = true;
2978 /* When the type has discriminants, and these discriminants
2979 affect the shape of what it built, factor them in.
2981 If we are making a subtype of an Unchecked_Union (must be an
2982 Itype), just return the type.
2984 We can't just use Is_Constrained because private subtypes without
2985 discriminants of full types with discriminants with default
2986 expressions are Is_Constrained but aren't constrained! */
2988 if (IN (Ekind (gnat_base_type), Record_Kind)
2989 && !Is_For_Access_Subtype (gnat_entity)
2990 && !Is_Unchecked_Union (gnat_base_type)
2991 && Is_Constrained (gnat_entity)
2992 && Stored_Constraint (gnat_entity) != No_Elist
2993 && Present (Discriminant_Constraint (gnat_entity)))
2995 Entity_Id gnat_field;
2996 tree gnu_field_list = 0;
2998 = compute_field_positions (gnu_orig_type, NULL_TREE,
2999 size_zero_node, bitsize_zero_node,
3002 = substitution_list (gnat_entity, gnat_base_type, NULL_TREE,
3006 gnu_type = make_node (RECORD_TYPE);
3007 TYPE_NAME (gnu_type) = gnu_entity_id;
3008 TYPE_VOLATILE (gnu_type) = Treat_As_Volatile (gnat_entity);
3010 /* Set the size, alignment and alias set of the new type to
3011 match that of the old one, doing required substitutions.
3012 We do it this early because we need the size of the new
3013 type below to discard old fields if necessary. */
3014 TYPE_SIZE (gnu_type) = TYPE_SIZE (gnu_base_type);
3015 TYPE_SIZE_UNIT (gnu_type) = TYPE_SIZE_UNIT (gnu_base_type);
3016 SET_TYPE_ADA_SIZE (gnu_type, TYPE_ADA_SIZE (gnu_base_type));
3017 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (gnu_base_type);
3018 relate_alias_sets (gnu_type, gnu_base_type, ALIAS_SET_COPY);
3020 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
3021 for (gnu_temp = gnu_subst_list;
3022 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3023 TYPE_SIZE (gnu_type)
3024 = substitute_in_expr (TYPE_SIZE (gnu_type),
3025 TREE_PURPOSE (gnu_temp),
3026 TREE_VALUE (gnu_temp));
3028 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE_UNIT (gnu_type)))
3029 for (gnu_temp = gnu_subst_list;
3030 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3031 TYPE_SIZE_UNIT (gnu_type)
3032 = substitute_in_expr (TYPE_SIZE_UNIT (gnu_type),
3033 TREE_PURPOSE (gnu_temp),
3034 TREE_VALUE (gnu_temp));
3036 if (CONTAINS_PLACEHOLDER_P (TYPE_ADA_SIZE (gnu_type)))
3037 for (gnu_temp = gnu_subst_list;
3038 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3040 (gnu_type, substitute_in_expr (TYPE_ADA_SIZE (gnu_type),
3041 TREE_PURPOSE (gnu_temp),
3042 TREE_VALUE (gnu_temp)));
3044 for (gnat_field = First_Entity (gnat_entity);
3045 Present (gnat_field); gnat_field = Next_Entity (gnat_field))
3046 if ((Ekind (gnat_field) == E_Component
3047 || Ekind (gnat_field) == E_Discriminant)
3048 && (Underlying_Type (Scope (Original_Record_Component
3051 && (No (Corresponding_Discriminant (gnat_field))
3052 || !Is_Tagged_Type (gnat_base_type)))
3055 = gnat_to_gnu_field_decl (Original_Record_Component
3058 = TREE_VALUE (purpose_member (gnu_old_field,
3060 tree gnu_pos = TREE_PURPOSE (gnu_offset);
3061 tree gnu_bitpos = TREE_VALUE (TREE_VALUE (gnu_offset));
3063 = gnat_to_gnu_type (Etype (gnat_field));
3064 tree gnu_size = TYPE_SIZE (gnu_field_type);
3065 tree gnu_new_pos = NULL_TREE;
3066 unsigned int offset_align
3067 = tree_low_cst (TREE_PURPOSE (TREE_VALUE (gnu_offset)),
3071 /* If there was a component clause, the field types must be
3072 the same for the type and subtype, so copy the data from
3073 the old field to avoid recomputation here. Also if the
3074 field is justified modular and the optimization in
3075 gnat_to_gnu_field was applied. */
3076 if (Present (Component_Clause
3077 (Original_Record_Component (gnat_field)))
3078 || (TREE_CODE (gnu_field_type) == RECORD_TYPE
3079 && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type)
3080 && TREE_TYPE (TYPE_FIELDS (gnu_field_type))
3081 == TREE_TYPE (gnu_old_field)))
3083 gnu_size = DECL_SIZE (gnu_old_field);
3084 gnu_field_type = TREE_TYPE (gnu_old_field);
3087 /* If the old field was packed and of constant size, we
3088 have to get the old size here, as it might differ from
3089 what the Etype conveys and the latter might overlap
3090 onto the following field. Try to arrange the type for
3091 possible better packing along the way. */
3092 else if (DECL_PACKED (gnu_old_field)
3093 && TREE_CODE (DECL_SIZE (gnu_old_field))
3096 gnu_size = DECL_SIZE (gnu_old_field);
3097 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
3098 && !TYPE_IS_FAT_POINTER_P (gnu_field_type)
3099 && host_integerp (TYPE_SIZE (gnu_field_type), 1))
3101 = make_packable_type (gnu_field_type, true);
3104 if (CONTAINS_PLACEHOLDER_P (gnu_pos))
3105 for (gnu_temp = gnu_subst_list;
3106 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3107 gnu_pos = substitute_in_expr (gnu_pos,
3108 TREE_PURPOSE (gnu_temp),
3109 TREE_VALUE (gnu_temp));
3111 /* If the position is now a constant, we can set it as the
3112 position of the field when we make it. Otherwise, we need
3113 to deal with it specially below. */
3114 if (TREE_CONSTANT (gnu_pos))
3116 gnu_new_pos = bit_from_pos (gnu_pos, gnu_bitpos);
3118 /* Discard old fields that are outside the new type.
3119 This avoids confusing code scanning it to decide
3120 how to pass it to functions on some platforms. */
3121 if (TREE_CODE (gnu_new_pos) == INTEGER_CST
3122 && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST
3123 && !integer_zerop (gnu_size)
3124 && !tree_int_cst_lt (gnu_new_pos,
3125 TYPE_SIZE (gnu_type)))
3131 (DECL_NAME (gnu_old_field), gnu_field_type, gnu_type,
3132 DECL_PACKED (gnu_old_field), gnu_size, gnu_new_pos,
3133 !DECL_NONADDRESSABLE_P (gnu_old_field));
3135 if (!TREE_CONSTANT (gnu_pos))
3137 normalize_offset (&gnu_pos, &gnu_bitpos, offset_align);
3138 DECL_FIELD_OFFSET (gnu_field) = gnu_pos;
3139 DECL_FIELD_BIT_OFFSET (gnu_field) = gnu_bitpos;
3140 SET_DECL_OFFSET_ALIGN (gnu_field, offset_align);
3141 DECL_SIZE (gnu_field) = gnu_size;
3142 DECL_SIZE_UNIT (gnu_field)
3143 = convert (sizetype,
3144 size_binop (CEIL_DIV_EXPR, gnu_size,
3145 bitsize_unit_node));
3146 layout_decl (gnu_field, DECL_OFFSET_ALIGN (gnu_field));
3149 DECL_INTERNAL_P (gnu_field)
3150 = DECL_INTERNAL_P (gnu_old_field);
3151 SET_DECL_ORIGINAL_FIELD
3152 (gnu_field, (DECL_ORIGINAL_FIELD (gnu_old_field)
3153 ? DECL_ORIGINAL_FIELD (gnu_old_field)
3155 DECL_DISCRIMINANT_NUMBER (gnu_field)
3156 = DECL_DISCRIMINANT_NUMBER (gnu_old_field);
3157 TREE_THIS_VOLATILE (gnu_field)
3158 = TREE_THIS_VOLATILE (gnu_old_field);
3160 /* To match the layout crafted in components_to_record, if
3161 this is the _Tag field, put it before any discriminants
3162 instead of after them as for all other fields. */
3163 if (Chars (gnat_field) == Name_uTag)
3164 gnu_field_list = chainon (gnu_field_list, gnu_field);
3167 TREE_CHAIN (gnu_field) = gnu_field_list;
3168 gnu_field_list = gnu_field;
3171 save_gnu_tree (gnat_field, gnu_field, false);
3174 /* Now go through the entities again looking for Itypes that
3175 we have not elaborated but should (e.g., Etypes of fields
3176 that have Original_Components). */
3177 for (gnat_field = First_Entity (gnat_entity);
3178 Present (gnat_field); gnat_field = Next_Entity (gnat_field))
3179 if ((Ekind (gnat_field) == E_Discriminant
3180 || Ekind (gnat_field) == E_Component)
3181 && !present_gnu_tree (Etype (gnat_field)))
3182 gnat_to_gnu_entity (Etype (gnat_field), NULL_TREE, 0);
3184 /* Do not finalize it since we're going to modify it below. */
3185 gnu_field_list = nreverse (gnu_field_list);
3186 finish_record_type (gnu_type, gnu_field_list, 2, true);
3188 /* Finalize size and mode. */
3189 TYPE_SIZE (gnu_type) = variable_size (TYPE_SIZE (gnu_type));
3190 TYPE_SIZE_UNIT (gnu_type)
3191 = variable_size (TYPE_SIZE_UNIT (gnu_type));
3193 compute_record_mode (gnu_type);
3195 /* Fill in locations of fields. */
3196 annotate_rep (gnat_entity, gnu_type);
3198 /* We've built a new type, make an XVS type to show what this
3199 is a subtype of. Some debuggers require the XVS type to be
3200 output first, so do it in that order. */
3203 tree gnu_subtype_marker = make_node (RECORD_TYPE);
3204 tree gnu_orig_name = TYPE_NAME (gnu_orig_type);
3206 if (TREE_CODE (gnu_orig_name) == TYPE_DECL)
3207 gnu_orig_name = DECL_NAME (gnu_orig_name);
3209 TYPE_NAME (gnu_subtype_marker)
3210 = create_concat_name (gnat_entity, "XVS");
3211 finish_record_type (gnu_subtype_marker,
3212 create_field_decl (gnu_orig_name,
3219 add_parallel_type (TYPE_STUB_DECL (gnu_type),
3220 gnu_subtype_marker);
3223 /* Now we can finalize it. */
3224 rest_of_record_type_compilation (gnu_type);
3227 /* Otherwise, go down all the components in the new type and
3228 make them equivalent to those in the base type. */
3230 for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp);
3231 gnat_temp = Next_Entity (gnat_temp))
3232 if ((Ekind (gnat_temp) == E_Discriminant
3233 && !Is_Unchecked_Union (gnat_base_type))
3234 || Ekind (gnat_temp) == E_Component)
3235 save_gnu_tree (gnat_temp,
3236 gnat_to_gnu_field_decl
3237 (Original_Record_Component (gnat_temp)), false);
3241 case E_Access_Subprogram_Type:
3242 /* Use the special descriptor type for dispatch tables if needed,
3243 that is to say for the Prim_Ptr of a-tags.ads and its clones.
3244 Note that we are only required to do so for static tables in
3245 order to be compatible with the C++ ABI, but Ada 2005 allows
3246 to extend library level tagged types at the local level so
3247 we do it in the non-static case as well. */
3248 if (TARGET_VTABLE_USES_DESCRIPTORS
3249 && Is_Dispatch_Table_Entity (gnat_entity))
3251 gnu_type = fdesc_type_node;
3252 gnu_size = TYPE_SIZE (gnu_type);
3256 /* ... fall through ... */
3258 case E_Anonymous_Access_Subprogram_Type:
3259 /* If we are not defining this entity, and we have incomplete
3260 entities being processed above us, make a dummy type and
3261 fill it in later. */
3262 if (!definition && defer_incomplete_level != 0)
3264 struct incomplete *p
3265 = (struct incomplete *) xmalloc (sizeof (struct incomplete));
3268 = build_pointer_type
3269 (make_dummy_type (Directly_Designated_Type (gnat_entity)));
3270 gnu_decl = create_type_decl (gnu_entity_id, gnu_type, attr_list,
3271 !Comes_From_Source (gnat_entity),
3272 debug_info_p, gnat_entity);
3273 this_made_decl = true;
3274 gnu_type = TREE_TYPE (gnu_decl);
3275 save_gnu_tree (gnat_entity, gnu_decl, false);
3278 p->old_type = TREE_TYPE (gnu_type);
3279 p->full_type = Directly_Designated_Type (gnat_entity);
3280 p->next = defer_incomplete_list;
3281 defer_incomplete_list = p;
3285 /* ... fall through ... */
3287 case E_Allocator_Type:
3289 case E_Access_Attribute_Type:
3290 case E_Anonymous_Access_Type:
3291 case E_General_Access_Type:
3293 Entity_Id gnat_desig_type = Directly_Designated_Type (gnat_entity);
3294 Entity_Id gnat_desig_equiv = Gigi_Equivalent_Type (gnat_desig_type);
3295 bool is_from_limited_with
3296 = (IN (Ekind (gnat_desig_equiv), Incomplete_Kind)
3297 && From_With_Type (gnat_desig_equiv));
3299 /* Get the "full view" of this entity. If this is an incomplete
3300 entity from a limited with, treat its non-limited view as the full
3301 view. Otherwise, if this is an incomplete or private type, use the
3302 full view. In the former case, we might point to a private type,
3303 in which case, we need its full view. Also, we want to look at the
3304 actual type used for the representation, so this takes a total of
3306 Entity_Id gnat_desig_full_direct_first
3307 = (is_from_limited_with ? Non_Limited_View (gnat_desig_equiv)
3308 : (IN (Ekind (gnat_desig_equiv), Incomplete_Or_Private_Kind)
3309 ? Full_View (gnat_desig_equiv) : Empty));
3310 Entity_Id gnat_desig_full_direct
3311 = ((is_from_limited_with
3312 && Present (gnat_desig_full_direct_first)
3313 && IN (Ekind (gnat_desig_full_direct_first), Private_Kind))
3314 ? Full_View (gnat_desig_full_direct_first)
3315 : gnat_desig_full_direct_first);
3316 Entity_Id gnat_desig_full
3317 = Gigi_Equivalent_Type (gnat_desig_full_direct);
3319 /* This the type actually used to represent the designated type,
3320 either gnat_desig_full or gnat_desig_equiv. */
3321 Entity_Id gnat_desig_rep;
3323 /* True if this is a pointer to an unconstrained array. */
3324 bool is_unconstrained_array;
3326 /* We want to know if we'll be seeing the freeze node for any
3327 incomplete type we may be pointing to. */
3329 = (Present (gnat_desig_full)
3330 ? In_Extended_Main_Code_Unit (gnat_desig_full)
3331 : In_Extended_Main_Code_Unit (gnat_desig_type));
3333 /* True if we make a dummy type here. */
3334 bool got_fat_p = false;
3335 /* True if the dummy is a fat pointer. */
3336 bool made_dummy = false;
3337 tree gnu_desig_type = NULL_TREE;
3338 enum machine_mode p_mode = mode_for_size (esize, MODE_INT, 0);
3340 if (!targetm.valid_pointer_mode (p_mode))
3343 /* If either the designated type or its full view is an unconstrained
3344 array subtype, replace it with the type it's a subtype of. This
3345 avoids problems with multiple copies of unconstrained array types.
3346 Likewise, if the designated type is a subtype of an incomplete
3347 record type, use the parent type to avoid order of elaboration
3348 issues. This can lose some code efficiency, but there is no
3350 if (Ekind (gnat_desig_equiv) == E_Array_Subtype
3351 && ! Is_Constrained (gnat_desig_equiv))
3352 gnat_desig_equiv = Etype (gnat_desig_equiv);
3353 if (Present (gnat_desig_full)
3354 && ((Ekind (gnat_desig_full) == E_Array_Subtype
3355 && ! Is_Constrained (gnat_desig_full))
3356 || (Ekind (gnat_desig_full) == E_Record_Subtype
3357 && Ekind (Etype (gnat_desig_full)) == E_Record_Type)))
3358 gnat_desig_full = Etype (gnat_desig_full);
3360 /* Now set the type that actually marks the representation of
3361 the designated type and also flag whether we have a unconstrained
3363 gnat_desig_rep = gnat_desig_full ? gnat_desig_full : gnat_desig_equiv;
3364 is_unconstrained_array
3365 = (Is_Array_Type (gnat_desig_rep)
3366 && ! Is_Constrained (gnat_desig_rep));
3368 /* If we are pointing to an incomplete type whose completion is an
3369 unconstrained array, make a fat pointer type. The two types in our
3370 fields will be pointers to dummy nodes and will be replaced in
3371 update_pointer_to. Similarly, if the type itself is a dummy type or
3372 an unconstrained array. Also make a dummy TYPE_OBJECT_RECORD_TYPE
3373 in case we have any thin pointers to it. */
3374 if (is_unconstrained_array
3375 && (Present (gnat_desig_full)
3376 || (present_gnu_tree (gnat_desig_equiv)
3377 && TYPE_IS_DUMMY_P (TREE_TYPE
3378 (get_gnu_tree (gnat_desig_equiv))))
3379 || (No (gnat_desig_full) && ! in_main_unit
3380 && defer_incomplete_level != 0
3381 && ! present_gnu_tree (gnat_desig_equiv))
3382 || (in_main_unit && is_from_limited_with
3383 && Present (Freeze_Node (gnat_desig_rep)))))
3386 = (present_gnu_tree (gnat_desig_rep)
3387 ? TREE_TYPE (get_gnu_tree (gnat_desig_rep))
3388 : make_dummy_type (gnat_desig_rep));
3391 /* Show the dummy we get will be a fat pointer. */
3392 got_fat_p = made_dummy = true;
3394 /* If the call above got something that has a pointer, that
3395 pointer is our type. This could have happened either
3396 because the type was elaborated or because somebody
3397 else executed the code below. */
3398 gnu_type = TYPE_POINTER_TO (gnu_old);
3401 tree gnu_template_type = make_node (ENUMERAL_TYPE);
3402 tree gnu_ptr_template = build_pointer_type (gnu_template_type);
3403 tree gnu_array_type = make_node (ENUMERAL_TYPE);
3404 tree gnu_ptr_array = build_pointer_type (gnu_array_type);
3406 TYPE_NAME (gnu_template_type)
3407 = concat_id_with_name (get_entity_name (gnat_desig_equiv),
3409 TYPE_DUMMY_P (gnu_template_type) = 1;
3411 TYPE_NAME (gnu_array_type)
3412 = concat_id_with_name (get_entity_name (gnat_desig_equiv),
3414 TYPE_DUMMY_P (gnu_array_type) = 1;
3416 gnu_type = make_node (RECORD_TYPE);
3417 SET_TYPE_UNCONSTRAINED_ARRAY (gnu_type, gnu_old);
3418 TYPE_POINTER_TO (gnu_old) = gnu_type;
3420 Sloc_to_locus (Sloc (gnat_entity), &input_location);
3422 = chainon (chainon (NULL_TREE,
3424 (get_identifier ("P_ARRAY"),
3426 gnu_type, 0, 0, 0, 0)),
3427 create_field_decl (get_identifier ("P_BOUNDS"),
3429 gnu_type, 0, 0, 0, 0));
3431 /* Make sure we can place this into a register. */
3432 TYPE_ALIGN (gnu_type)
3433 = MIN (BIGGEST_ALIGNMENT, 2 * POINTER_SIZE);
3434 TYPE_IS_FAT_POINTER_P (gnu_type) = 1;
3436 /* Do not finalize this record type since the types of
3437 its fields are incomplete. */
3438 finish_record_type (gnu_type, fields, 0, true);
3440 TYPE_OBJECT_RECORD_TYPE (gnu_old) = make_node (RECORD_TYPE);
3441 TYPE_NAME (TYPE_OBJECT_RECORD_TYPE (gnu_old))
3442 = concat_id_with_name (get_entity_name (gnat_desig_equiv),
3444 TYPE_DUMMY_P (TYPE_OBJECT_RECORD_TYPE (gnu_old)) = 1;
3448 /* If we already know what the full type is, use it. */
3449 else if (Present (gnat_desig_full)
3450 && present_gnu_tree (gnat_desig_full))
3451 gnu_desig_type = TREE_TYPE (get_gnu_tree (gnat_desig_full));
3453 /* Get the type of the thing we are to point to and build a pointer
3454 to it. If it is a reference to an incomplete or private type with a
3455 full view that is a record, make a dummy type node and get the
3456 actual type later when we have verified it is safe. */
3457 else if ((! in_main_unit
3458 && ! present_gnu_tree (gnat_desig_equiv)
3459 && Present (gnat_desig_full)
3460 && ! present_gnu_tree (gnat_desig_full)
3461 && Is_Record_Type (gnat_desig_full))
3462 /* Likewise if we are pointing to a record or array and we
3463 are to defer elaborating incomplete types. We do this
3464 since this access type may be the full view of some
3465 private type. Note that the unconstrained array case is
3467 || ((! in_main_unit || imported_p)
3468 && defer_incomplete_level != 0
3469 && ! present_gnu_tree (gnat_desig_equiv)
3470 && ((Is_Record_Type (gnat_desig_rep)
3471 || Is_Array_Type (gnat_desig_rep))))
3472 /* If this is a reference from a limited_with type back to our
3473 main unit and there's a Freeze_Node for it, either we have
3474 already processed the declaration and made the dummy type,
3475 in which case we just reuse the latter, or we have not yet,
3476 in which case we make the dummy type and it will be reused
3477 when the declaration is processed. In both cases, the
3478 pointer eventually created below will be automatically
3479 adjusted when the Freeze_Node is processed. Note that the
3480 unconstrained array case is handled above. */
3481 || (in_main_unit && is_from_limited_with
3482 && Present (Freeze_Node (gnat_desig_rep))))
3484 gnu_desig_type = make_dummy_type (gnat_desig_equiv);
3488 /* Otherwise handle the case of a pointer to itself. */
3489 else if (gnat_desig_equiv == gnat_entity)
3492 = build_pointer_type_for_mode (void_type_node, p_mode,
3493 No_Strict_Aliasing (gnat_entity));
3494 TREE_TYPE (gnu_type) = TYPE_POINTER_TO (gnu_type) = gnu_type;
3497 /* If expansion is disabled, the equivalent type of a concurrent
3498 type is absent, so build a dummy pointer type. */
3499 else if (type_annotate_only && No (gnat_desig_equiv))
3500 gnu_type = ptr_void_type_node;
3502 /* Finally, handle the straightforward case where we can just
3503 elaborate our designated type and point to it. */
3505 gnu_desig_type = gnat_to_gnu_type (gnat_desig_equiv);
3507 /* It is possible that a call to gnat_to_gnu_type above resolved our
3508 type. If so, just return it. */
3509 if (present_gnu_tree (gnat_entity))
3511 maybe_present = true;
3515 /* If we have a GCC type for the designated type, possibly modify it
3516 if we are pointing only to constant objects and then make a pointer
3517 to it. Don't do this for unconstrained arrays. */
3518 if (!gnu_type && gnu_desig_type)
3520 if (Is_Access_Constant (gnat_entity)
3521 && TREE_CODE (gnu_desig_type) != UNCONSTRAINED_ARRAY_TYPE)
3524 = build_qualified_type
3526 TYPE_QUALS (gnu_desig_type) | TYPE_QUAL_CONST);
3528 /* Some extra processing is required if we are building a
3529 pointer to an incomplete type (in the GCC sense). We might
3530 have such a type if we just made a dummy, or directly out
3531 of the call to gnat_to_gnu_type above if we are processing
3532 an access type for a record component designating the
3533 record type itself. */
3534 if (TYPE_MODE (gnu_desig_type) == VOIDmode)
3536 /* We must ensure that the pointer to variant we make will
3537 be processed by update_pointer_to when the initial type
3538 is completed. Pretend we made a dummy and let further
3539 processing act as usual. */
3542 /* We must ensure that update_pointer_to will not retrieve
3543 the dummy variant when building a properly qualified
3544 version of the complete type. We take advantage of the
3545 fact that get_qualified_type is requiring TYPE_NAMEs to
3546 match to influence build_qualified_type and then also
3547 update_pointer_to here. */
3548 TYPE_NAME (gnu_desig_type)
3549 = create_concat_name (gnat_desig_type, "INCOMPLETE_CST");
3554 = build_pointer_type_for_mode (gnu_desig_type, p_mode,
3555 No_Strict_Aliasing (gnat_entity));
3558 /* If we are not defining this object and we made a dummy pointer,
3559 save our current definition, evaluate the actual type, and replace
3560 the tentative type we made with the actual one. If we are to defer
3561 actually looking up the actual type, make an entry in the
3562 deferred list. If this is from a limited with, we have to defer
3563 to the end of the current spec in two cases: first if the
3564 designated type is in the current unit and second if the access
3566 if ((! in_main_unit || is_from_limited_with) && made_dummy)
3569 = TYPE_FAT_POINTER_P (gnu_type)
3570 ? TYPE_UNCONSTRAINED_ARRAY (gnu_type) : TREE_TYPE (gnu_type);
3572 if (esize == POINTER_SIZE
3573 && (got_fat_p || TYPE_FAT_POINTER_P (gnu_type)))
3575 = build_pointer_type
3576 (TYPE_OBJECT_RECORD_TYPE
3577 (TYPE_UNCONSTRAINED_ARRAY (gnu_type)));
3579 gnu_decl = create_type_decl (gnu_entity_id, gnu_type, attr_list,
3580 !Comes_From_Source (gnat_entity),
3581 debug_info_p, gnat_entity);
3582 this_made_decl = true;
3583 gnu_type = TREE_TYPE (gnu_decl);
3584 save_gnu_tree (gnat_entity, gnu_decl, false);
3587 if (defer_incomplete_level == 0
3588 && ! (is_from_limited_with
3590 || In_Extended_Main_Code_Unit (gnat_entity))))
3591 update_pointer_to (TYPE_MAIN_VARIANT (gnu_old_type),
3592 gnat_to_gnu_type (gnat_desig_equiv));
3594 /* Note that the call to gnat_to_gnu_type here might have
3595 updated gnu_old_type directly, in which case it is not a
3596 dummy type any more when we get into update_pointer_to.
3598 This may happen for instance when the designated type is a
3599 record type, because their elaboration starts with an
3600 initial node from make_dummy_type, which may yield the same
3601 node as the one we got.
3603 Besides, variants of this non-dummy type might have been
3604 created along the way. update_pointer_to is expected to
3605 properly take care of those situations. */
3608 struct incomplete *p
3609 = (struct incomplete *) xmalloc (sizeof
3610 (struct incomplete));
3611 struct incomplete **head
3612 = (is_from_limited_with
3614 || In_Extended_Main_Code_Unit (gnat_entity))
3615 ? &defer_limited_with : &defer_incomplete_list);
3617 p->old_type = gnu_old_type;
3618 p->full_type = gnat_desig_equiv;
3626 case E_Access_Protected_Subprogram_Type:
3627 case E_Anonymous_Access_Protected_Subprogram_Type:
3628 if (type_annotate_only && No (gnat_equiv_type))
3629 gnu_type = ptr_void_type_node;
3632 /* The runtime representation is the equivalent type. */
3633 gnu_type = gnat_to_gnu_type (gnat_equiv_type);
3634 maybe_present = true;
3637 if (Is_Itype (Directly_Designated_Type (gnat_entity))
3638 && !present_gnu_tree (Directly_Designated_Type (gnat_entity))
3639 && No (Freeze_Node (Directly_Designated_Type (gnat_entity)))
3640 && !Is_Record_Type (Scope (Directly_Designated_Type (gnat_entity))))
3641 gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity),
3646 case E_Access_Subtype:
3648 /* We treat this as identical to its base type; any constraint is
3649 meaningful only to the front end.
3651 The designated type must be elaborated as well, if it does
3652 not have its own freeze node. Designated (sub)types created
3653 for constrained components of records with discriminants are
3654 not frozen by the front end and thus not elaborated by gigi,
3655 because their use may appear before the base type is frozen,
3656 and because it is not clear that they are needed anywhere in
3657 Gigi. With the current model, there is no correct place where
3658 they could be elaborated. */
3660 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
3661 if (Is_Itype (Directly_Designated_Type (gnat_entity))
3662 && !present_gnu_tree (Directly_Designated_Type (gnat_entity))
3663 && Is_Frozen (Directly_Designated_Type (gnat_entity))
3664 && No (Freeze_Node (Directly_Designated_Type (gnat_entity))))
3666 /* If we are not defining this entity, and we have incomplete
3667 entities being processed above us, make a dummy type and
3668 elaborate it later. */
3669 if (!definition && defer_incomplete_level != 0)
3671 struct incomplete *p
3672 = (struct incomplete *) xmalloc (sizeof (struct incomplete));
3674 = build_pointer_type
3675 (make_dummy_type (Directly_Designated_Type (gnat_entity)));
3677 p->old_type = TREE_TYPE (gnu_ptr_type);
3678 p->full_type = Directly_Designated_Type (gnat_entity);
3679 p->next = defer_incomplete_list;
3680 defer_incomplete_list = p;
3682 else if (!IN (Ekind (Base_Type
3683 (Directly_Designated_Type (gnat_entity))),
3684 Incomplete_Or_Private_Kind))
3685 gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity),
3689 maybe_present = true;
3692 /* Subprogram Entities
3694 The following access functions are defined for subprograms (functions
3697 First_Formal The first formal parameter.
3698 Is_Imported Indicates that the subprogram has appeared in
3699 an INTERFACE or IMPORT pragma. For now we
3700 assume that the external language is C.
3701 Is_Exported Likewise but for an EXPORT pragma.
3702 Is_Inlined True if the subprogram is to be inlined.
3704 In addition for function subprograms we have:
3706 Etype Return type of the function.
3708 Each parameter is first checked by calling must_pass_by_ref on its
3709 type to determine if it is passed by reference. For parameters which
3710 are copied in, if they are Ada In Out or Out parameters, their return
3711 value becomes part of a record which becomes the return type of the
3712 function (C function - note that this applies only to Ada procedures
3713 so there is no Ada return type). Additional code to store back the
3714 parameters will be generated on the caller side. This transformation
3715 is done here, not in the front-end.
3717 The intended result of the transformation can be seen from the
3718 equivalent source rewritings that follow:
3720 struct temp {int a,b};
3721 procedure P (A,B: In Out ...) is temp P (int A,B)
3724 end P; return {A,B};
3731 For subprogram types we need to perform mainly the same conversions to
3732 GCC form that are needed for procedures and function declarations. The
3733 only difference is that at the end, we make a type declaration instead
3734 of a function declaration. */
3736 case E_Subprogram_Type:
3740 /* The first GCC parameter declaration (a PARM_DECL node). The
3741 PARM_DECL nodes are chained through the TREE_CHAIN field, so this
3742 actually is the head of this parameter list. */
3743 tree gnu_param_list = NULL_TREE;
3744 /* Likewise for the stub associated with an exported procedure. */
3745 tree gnu_stub_param_list = NULL_TREE;
3746 /* The type returned by a function. If the subprogram is a procedure
3747 this type should be void_type_node. */
3748 tree gnu_return_type = void_type_node;
3749 /* List of fields in return type of procedure with copy-in copy-out
3751 tree gnu_field_list = NULL_TREE;
3752 /* Non-null for subprograms containing parameters passed by copy-in
3753 copy-out (Ada In Out or Out parameters not passed by reference),
3754 in which case it is the list of nodes used to specify the values of
3755 the in out/out parameters that are returned as a record upon
3756 procedure return. The TREE_PURPOSE of an element of this list is
3757 a field of the record and the TREE_VALUE is the PARM_DECL
3758 corresponding to that field. This list will be saved in the
3759 TYPE_CI_CO_LIST field of the FUNCTION_TYPE node we create. */
3760 tree gnu_return_list = NULL_TREE;
3761 /* If an import pragma asks to map this subprogram to a GCC builtin,
3762 this is the builtin DECL node. */
3763 tree gnu_builtin_decl = NULL_TREE;
3764 /* For the stub associated with an exported procedure. */
3765 tree gnu_stub_type = NULL_TREE, gnu_stub_name = NULL_TREE;
3766 tree gnu_ext_name = create_concat_name (gnat_entity, NULL);
3767 Entity_Id gnat_param;
3768 bool inline_flag = Is_Inlined (gnat_entity);
3769 bool public_flag = Is_Public (gnat_entity) || imported_p;
3771 = (Is_Public (gnat_entity) && !definition) || imported_p;
3773 /* The semantics of "pure" in Ada essentially matches that of "const"
3774 in the back-end. In particular, both properties are orthogonal to
3775 the "nothrow" property if the EH circuitry is explicit in the
3776 internal representation of the back-end. If we are to completely
3777 hide the EH circuitry from it, we need to declare that calls to pure
3778 Ada subprograms that can throw have side effects since they can
3779 trigger an "abnormal" transfer of control flow; thus they can be
3780 neither "const" nor "pure" in the back-end sense. */
3782 = (Exception_Mechanism == Back_End_Exceptions
3783 && Is_Pure (gnat_entity));
3785 bool volatile_flag = No_Return (gnat_entity);
3786 bool returns_by_ref = false;
3787 bool returns_unconstrained = false;
3788 bool returns_by_target_ptr = false;
3789 bool has_copy_in_out = false;
3790 bool has_stub = false;
3793 if (kind == E_Subprogram_Type && !definition)
3794 /* A parameter may refer to this type, so defer completion
3795 of any incomplete types. */
3796 defer_incomplete_level++, this_deferred = true;
3798 /* If the subprogram has an alias, it is probably inherited, so
3799 we can use the original one. If the original "subprogram"
3800 is actually an enumeration literal, it may be the first use
3801 of its type, so we must elaborate that type now. */
3802 if (Present (Alias (gnat_entity)))
3804 if (Ekind (Alias (gnat_entity)) == E_Enumeration_Literal)
3805 gnat_to_gnu_entity (Etype (Alias (gnat_entity)), NULL_TREE, 0);
3807 gnu_decl = gnat_to_gnu_entity (Alias (gnat_entity),
3810 /* Elaborate any Itypes in the parameters of this entity. */
3811 for (gnat_temp = First_Formal_With_Extras (gnat_entity);
3812 Present (gnat_temp);
3813 gnat_temp = Next_Formal_With_Extras (gnat_temp))
3814 if (Is_Itype (Etype (gnat_temp)))
3815 gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0);
3820 /* If this subprogram is expectedly bound to a GCC builtin, fetch the
3821 corresponding DECL node.
3823 We still want the parameter associations to take place because the
3824 proper generation of calls depends on it (a GNAT parameter without
3825 a corresponding GCC tree has a very specific meaning), so we don't
3827 if (Convention (gnat_entity) == Convention_Intrinsic)
3828 gnu_builtin_decl = builtin_decl_for (gnu_ext_name);
3830 /* ??? What if we don't find the builtin node above ? warn ? err ?
3831 In the current state we neither warn nor err, and calls will just
3832 be handled as for regular subprograms. */
3834 if (kind == E_Function || kind == E_Subprogram_Type)
3835 gnu_return_type = gnat_to_gnu_type (Etype (gnat_entity));
3837 /* If this function returns by reference, make the actual
3838 return type of this function the pointer and mark the decl. */
3839 if (Returns_By_Ref (gnat_entity))
3841 returns_by_ref = true;
3842 gnu_return_type = build_pointer_type (gnu_return_type);
3845 /* If the Mechanism is By_Reference, ensure the return type uses
3846 the machine's by-reference mechanism, which may not the same
3847 as above (e.g., it might be by passing a fake parameter). */
3848 else if (kind == E_Function
3849 && Mechanism (gnat_entity) == By_Reference)
3851 TREE_ADDRESSABLE (gnu_return_type) = 1;
3853 /* We expect this bit to be reset by gigi shortly, so can avoid a
3854 type node copy here. This actually also prevents troubles with
3855 the generation of debug information for the function, because
3856 we might have issued such info for this type already, and would
3857 be attaching a distinct type node to the function if we made a
3861 /* If we are supposed to return an unconstrained array,
3862 actually return a fat pointer and make a note of that. Return
3863 a pointer to an unconstrained record of variable size. */
3864 else if (TREE_CODE (gnu_return_type) == UNCONSTRAINED_ARRAY_TYPE)
3866 gnu_return_type = TREE_TYPE (gnu_return_type);
3867 returns_unconstrained = true;
3870 /* If the type requires a transient scope, the result is allocated
3871 on the secondary stack, so the result type of the function is
3873 else if (Requires_Transient_Scope (Etype (gnat_entity)))
3875 gnu_return_type = build_pointer_type (gnu_return_type);
3876 returns_unconstrained = true;
3879 /* If the type is a padded type and the underlying type would not
3880 be passed by reference or this function has a foreign convention,
3881 return the underlying type. */
3882 else if (TREE_CODE (gnu_return_type) == RECORD_TYPE
3883 && TYPE_IS_PADDING_P (gnu_return_type)
3884 && (!default_pass_by_ref (TREE_TYPE
3885 (TYPE_FIELDS (gnu_return_type)))
3886 || Has_Foreign_Convention (gnat_entity)))
3887 gnu_return_type = TREE_TYPE (TYPE_FIELDS (gnu_return_type));
3889 /* If the return type has a non-constant size, we convert the function
3890 into a procedure and its caller will pass a pointer to an object as
3891 the first parameter when we call the function. This can happen for
3892 an unconstrained type with a maximum size or a constrained type with
3893 a size not known at compile time. */
3894 if (TYPE_SIZE_UNIT (gnu_return_type)
3895 && !TREE_CONSTANT (TYPE_SIZE_UNIT (gnu_return_type)))
3897 returns_by_target_ptr = true;
3899 = create_param_decl (get_identifier ("TARGET"),
3900 build_reference_type (gnu_return_type),
3902 gnu_return_type = void_type_node;
3905 /* If the return type has a size that overflows, we cannot have
3906 a function that returns that type. This usage doesn't make
3907 sense anyway, so give an error here. */
3908 if (TYPE_SIZE_UNIT (gnu_return_type)
3909 && TREE_CONSTANT (TYPE_SIZE_UNIT (gnu_return_type))
3910 && TREE_OVERFLOW (TYPE_SIZE_UNIT (gnu_return_type)))
3912 post_error ("cannot return type whose size overflows",
3914 gnu_return_type = copy_node (gnu_return_type);
3915 TYPE_SIZE (gnu_return_type) = bitsize_zero_node;
3916 TYPE_SIZE_UNIT (gnu_return_type) = size_zero_node;
3917 TYPE_MAIN_VARIANT (gnu_return_type) = gnu_return_type;
3918 TYPE_NEXT_VARIANT (gnu_return_type) = NULL_TREE;
3921 /* Look at all our parameters and get the type of
3922 each. While doing this, build a copy-out structure if
3925 /* Loop over the parameters and get their associated GCC tree.
3926 While doing this, build a copy-out structure if we need one. */
3927 for (gnat_param = First_Formal_With_Extras (gnat_entity), parmnum = 0;
3928 Present (gnat_param);
3929 gnat_param = Next_Formal_With_Extras (gnat_param), parmnum++)
3931 tree gnu_param_name = get_entity_name (gnat_param);
3932 tree gnu_param_type = gnat_to_gnu_type (Etype (gnat_param));
3933 tree gnu_param, gnu_field;
3934 bool copy_in_copy_out = false;
3935 Mechanism_Type mech = Mechanism (gnat_param);
3937 /* Builtins are expanded inline and there is no real call sequence
3938 involved. So the type expected by the underlying expander is
3939 always the type of each argument "as is". */
3940 if (gnu_builtin_decl)
3942 /* Handle the first parameter of a valued procedure specially. */
3943 else if (Is_Valued_Procedure (gnat_entity) && parmnum == 0)
3944 mech = By_Copy_Return;
3945 /* Otherwise, see if a Mechanism was supplied that forced this
3946 parameter to be passed one way or another. */
3947 else if (mech == Default
3948 || mech == By_Copy || mech == By_Reference)
3950 else if (By_Descriptor_Last <= mech && mech <= By_Descriptor)
3951 mech = By_Descriptor;
3953 else if (By_Short_Descriptor_Last <= mech &&
3954 mech <= By_Short_Descriptor)
3955 mech = By_Short_Descriptor;
3959 if (TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE
3960 || TREE_CODE (TYPE_SIZE (gnu_param_type)) != INTEGER_CST
3961 || 0 < compare_tree_int (TYPE_SIZE (gnu_param_type),
3963 mech = By_Reference;
3969 post_error ("unsupported mechanism for&", gnat_param);
3974 = gnat_to_gnu_param (gnat_param, mech, gnat_entity,
3975 Has_Foreign_Convention (gnat_entity),
3978 /* We are returned either a PARM_DECL or a type if no parameter
3979 needs to be passed; in either case, adjust the type. */
3980 if (DECL_P (gnu_param))
3981 gnu_param_type = TREE_TYPE (gnu_param);
3984 gnu_param_type = gnu_param;
3985 gnu_param = NULL_TREE;
3990 /* If it's an exported subprogram, we build a parameter list
3991 in parallel, in case we need to emit a stub for it. */
3992 if (Is_Exported (gnat_entity))
3995 = chainon (gnu_param, gnu_stub_param_list);
3996 /* Change By_Descriptor parameter to By_Reference for
3997 the internal version of an exported subprogram. */
3998 if (mech == By_Descriptor || mech == By_Short_Descriptor)
4001 = gnat_to_gnu_param (gnat_param, By_Reference,
4007 gnu_param = copy_node (gnu_param);
4010 gnu_param_list = chainon (gnu_param, gnu_param_list);
4011 Sloc_to_locus (Sloc (gnat_param),
4012 &DECL_SOURCE_LOCATION (gnu_param));
4013 save_gnu_tree (gnat_param, gnu_param, false);
4015 /* If a parameter is a pointer, this function may modify
4016 memory through it and thus shouldn't be considered
4017 a const function. Also, the memory may be modified
4018 between two calls, so they can't be CSE'ed. The latter
4019 case also handles by-ref parameters. */
4020 if (POINTER_TYPE_P (gnu_param_type)
4021 || TYPE_FAT_POINTER_P (gnu_param_type))
4025 if (copy_in_copy_out)
4027 if (!has_copy_in_out)
4029 gcc_assert (TREE_CODE (gnu_return_type) == VOID_TYPE);
4030 gnu_return_type = make_node (RECORD_TYPE);
4031 TYPE_NAME (gnu_return_type) = get_identifier ("RETURN");
4032 has_copy_in_out = true;
4035 gnu_field = create_field_decl (gnu_param_name, gnu_param_type,
4036 gnu_return_type, 0, 0, 0, 0);
4037 Sloc_to_locus (Sloc (gnat_param),
4038 &DECL_SOURCE_LOCATION (gnu_field));
4039 TREE_CHAIN (gnu_field) = gnu_field_list;
4040 gnu_field_list = gnu_field;
4041 gnu_return_list = tree_cons (gnu_field, gnu_param,
4046 /* Do not compute record for out parameters if subprogram is
4047 stubbed since structures are incomplete for the back-end. */
4048 if (gnu_field_list && Convention (gnat_entity) != Convention_Stubbed)
4049 finish_record_type (gnu_return_type, nreverse (gnu_field_list),
4052 /* If we have a CICO list but it has only one entry, we convert
4053 this function into a function that simply returns that one
4055 if (list_length (gnu_return_list) == 1)
4056 gnu_return_type = TREE_TYPE (TREE_PURPOSE (gnu_return_list));
4058 if (Has_Stdcall_Convention (gnat_entity))
4059 prepend_one_attribute_to
4060 (&attr_list, ATTR_MACHINE_ATTRIBUTE,
4061 get_identifier ("stdcall"), NULL_TREE,
4064 /* If we are on a target where stack realignment is needed for 'main'
4065 to honor GCC's implicit expectations (stack alignment greater than
4066 what the base ABI guarantees), ensure we do the same for foreign
4067 convention subprograms as they might be used as callbacks from code
4068 breaking such expectations. Note that this applies to task entry
4069 points in particular. */
4070 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
4071 && Has_Foreign_Convention (gnat_entity))
4072 prepend_one_attribute_to
4073 (&attr_list, ATTR_MACHINE_ATTRIBUTE,
4074 get_identifier ("force_align_arg_pointer"), NULL_TREE,
4077 /* The lists have been built in reverse. */
4078 gnu_param_list = nreverse (gnu_param_list);
4080 gnu_stub_param_list = nreverse (gnu_stub_param_list);
4081 gnu_return_list = nreverse (gnu_return_list);
4083 if (Ekind (gnat_entity) == E_Function)
4084 Set_Mechanism (gnat_entity,
4085 (returns_by_ref || returns_unconstrained
4086 ? By_Reference : By_Copy));
4088 = create_subprog_type (gnu_return_type, gnu_param_list,
4089 gnu_return_list, returns_unconstrained,
4090 returns_by_ref, returns_by_target_ptr);
4094 = create_subprog_type (gnu_return_type, gnu_stub_param_list,
4095 gnu_return_list, returns_unconstrained,
4096 returns_by_ref, returns_by_target_ptr);
4098 /* A subprogram (something that doesn't return anything) shouldn't
4099 be considered const since there would be no reason for such a
4100 subprogram. Note that procedures with Out (or In Out) parameters
4101 have already been converted into a function with a return type. */
4102 if (TREE_CODE (gnu_return_type) == VOID_TYPE)
4106 = build_qualified_type (gnu_type,
4107 TYPE_QUALS (gnu_type)
4108 | (TYPE_QUAL_CONST * const_flag)
4109 | (TYPE_QUAL_VOLATILE * volatile_flag));
4111 Sloc_to_locus (Sloc (gnat_entity), &input_location);
4115 = build_qualified_type (gnu_stub_type,
4116 TYPE_QUALS (gnu_stub_type)
4117 | (TYPE_QUAL_CONST * const_flag)
4118 | (TYPE_QUAL_VOLATILE * volatile_flag));
4120 /* If we have a builtin decl for that function, check the signatures
4121 compatibilities. If the signatures are compatible, use the builtin
4122 decl. If they are not, we expect the checker predicate to have
4123 posted the appropriate errors, and just continue with what we have
4125 if (gnu_builtin_decl)
4127 tree gnu_builtin_type = TREE_TYPE (gnu_builtin_decl);
4129 if (compatible_signatures_p (gnu_type, gnu_builtin_type))
4131 gnu_decl = gnu_builtin_decl;
4132 gnu_type = gnu_builtin_type;
4137 /* If there was no specified Interface_Name and the external and
4138 internal names of the subprogram are the same, only use the
4139 internal name to allow disambiguation of nested subprograms. */
4140 if (No (Interface_Name (gnat_entity)) && gnu_ext_name == gnu_entity_id)
4141 gnu_ext_name = NULL_TREE;
4143 /* If we are defining the subprogram and it has an Address clause
4144 we must get the address expression from the saved GCC tree for the
4145 subprogram if it has a Freeze_Node. Otherwise, we elaborate
4146 the address expression here since the front-end has guaranteed
4147 in that case that the elaboration has no effects. If there is
4148 an Address clause and we are not defining the object, just
4149 make it a constant. */
4150 if (Present (Address_Clause (gnat_entity)))
4152 tree gnu_address = NULL_TREE;
4156 = (present_gnu_tree (gnat_entity)
4157 ? get_gnu_tree (gnat_entity)
4158 : gnat_to_gnu (Expression (Address_Clause (gnat_entity))));
4160 save_gnu_tree (gnat_entity, NULL_TREE, false);
4162 /* Convert the type of the object to a reference type that can
4163 alias everything as per 13.3(19). */
4165 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
4167 gnu_address = convert (gnu_type, gnu_address);
4170 = create_var_decl (gnu_entity_id, gnu_ext_name, gnu_type,
4171 gnu_address, false, Is_Public (gnat_entity),
4172 extern_flag, false, NULL, gnat_entity);
4173 DECL_BY_REF_P (gnu_decl) = 1;
4176 else if (kind == E_Subprogram_Type)
4177 gnu_decl = create_type_decl (gnu_entity_id, gnu_type, attr_list,
4178 !Comes_From_Source (gnat_entity),
4179 debug_info_p, gnat_entity);
4184 gnu_stub_name = gnu_ext_name;
4185 gnu_ext_name = create_concat_name (gnat_entity, "internal");
4186 public_flag = false;
4189 gnu_decl = create_subprog_decl (gnu_entity_id, gnu_ext_name,
4190 gnu_type, gnu_param_list,
4191 inline_flag, public_flag,
4192 extern_flag, attr_list,
4197 = create_subprog_decl (gnu_entity_id, gnu_stub_name,
4198 gnu_stub_type, gnu_stub_param_list,
4200 extern_flag, attr_list,
4202 SET_DECL_FUNCTION_STUB (gnu_decl, gnu_stub_decl);
4205 /* This is unrelated to the stub built right above. */
4206 DECL_STUBBED_P (gnu_decl)
4207 = Convention (gnat_entity) == Convention_Stubbed;
4212 case E_Incomplete_Type:
4213 case E_Incomplete_Subtype:
4214 case E_Private_Type:
4215 case E_Private_Subtype:
4216 case E_Limited_Private_Type:
4217 case E_Limited_Private_Subtype:
4218 case E_Record_Type_With_Private:
4219 case E_Record_Subtype_With_Private:
4221 /* Get the "full view" of this entity. If this is an incomplete
4222 entity from a limited with, treat its non-limited view as the
4223 full view. Otherwise, use either the full view or the underlying
4224 full view, whichever is present. This is used in all the tests
4227 = (IN (Ekind (gnat_entity), Incomplete_Kind)
4228 && From_With_Type (gnat_entity))
4229 ? Non_Limited_View (gnat_entity)
4230 : Present (Full_View (gnat_entity))
4231 ? Full_View (gnat_entity)
4232 : Underlying_Full_View (gnat_entity);
4234 /* If this is an incomplete type with no full view, it must be a Taft
4235 Amendment type, in which case we return a dummy type. Otherwise,
4236 just get the type from its Etype. */
4239 if (kind == E_Incomplete_Type)
4241 gnu_type = make_dummy_type (gnat_entity);
4242 gnu_decl = TYPE_STUB_DECL (gnu_type);
4246 gnu_decl = gnat_to_gnu_entity (Etype (gnat_entity),
4248 maybe_present = true;
4253 /* If we already made a type for the full view, reuse it. */
4254 else if (present_gnu_tree (full_view))
4256 gnu_decl = get_gnu_tree (full_view);
4260 /* Otherwise, if we are not defining the type now, get the type
4261 from the full view. But always get the type from the full view
4262 for define on use types, since otherwise we won't see them! */
4263 else if (!definition
4264 || (Is_Itype (full_view)
4265 && No (Freeze_Node (gnat_entity)))
4266 || (Is_Itype (gnat_entity)
4267 && No (Freeze_Node (full_view))))
4269 gnu_decl = gnat_to_gnu_entity (full_view, NULL_TREE, 0);
4270 maybe_present = true;
4274 /* For incomplete types, make a dummy type entry which will be
4275 replaced later. Save it as the full declaration's type so
4276 we can do any needed updates when we see it. */
4277 gnu_type = make_dummy_type (gnat_entity);
4278 gnu_decl = TYPE_STUB_DECL (gnu_type);
4279 save_gnu_tree (full_view, gnu_decl, 0);
4283 /* Simple class_wide types are always viewed as their root_type
4284 by Gigi unless an Equivalent_Type is specified. */
4285 case E_Class_Wide_Type:
4286 gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0);
4287 maybe_present = true;
4291 case E_Task_Subtype:
4292 case E_Protected_Type:
4293 case E_Protected_Subtype:
4294 if (type_annotate_only && No (gnat_equiv_type))
4295 gnu_type = void_type_node;
4297 gnu_type = gnat_to_gnu_type (gnat_equiv_type);
4299 maybe_present = true;
4303 gnu_decl = create_label_decl (gnu_entity_id);
4308 /* Nothing at all to do here, so just return an ERROR_MARK and claim
4309 we've already saved it, so we don't try to. */
4310 gnu_decl = error_mark_node;
4318 /* If we had a case where we evaluated another type and it might have
4319 defined this one, handle it here. */
4320 if (maybe_present && present_gnu_tree (gnat_entity))
4322 gnu_decl = get_gnu_tree (gnat_entity);
4326 /* If we are processing a type and there is either no decl for it or
4327 we just made one, do some common processing for the type, such as
4328 handling alignment and possible padding. */
4330 if ((!gnu_decl || this_made_decl) && IN (kind, Type_Kind))
4332 if (Is_Tagged_Type (gnat_entity)
4333 || Is_Class_Wide_Equivalent_Type (gnat_entity))
4334 TYPE_ALIGN_OK (gnu_type) = 1;
4336 if (AGGREGATE_TYPE_P (gnu_type) && Is_By_Reference_Type (gnat_entity))
4337 TYPE_BY_REFERENCE_P (gnu_type) = 1;
4339 /* ??? Don't set the size for a String_Literal since it is either
4340 confirming or we don't handle it properly (if the low bound is
4342 if (!gnu_size && kind != E_String_Literal_Subtype)
4343 gnu_size = validate_size (Esize (gnat_entity), gnu_type, gnat_entity,
4345 Has_Size_Clause (gnat_entity));
4347 /* If a size was specified, see if we can make a new type of that size
4348 by rearranging the type, for example from a fat to a thin pointer. */
4352 = make_type_from_size (gnu_type, gnu_size,
4353 Has_Biased_Representation (gnat_entity));
4355 if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0)
4356 && operand_equal_p (rm_size (gnu_type), gnu_size, 0))
4360 /* If the alignment hasn't already been processed and this is
4361 not an unconstrained array, see if an alignment is specified.
4362 If not, we pick a default alignment for atomic objects. */
4363 if (align != 0 || TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE)
4365 else if (Known_Alignment (gnat_entity))
4367 align = validate_alignment (Alignment (gnat_entity), gnat_entity,
4368 TYPE_ALIGN (gnu_type));
4370 /* Warn on suspiciously large alignments. This should catch
4371 errors about the (alignment,byte)/(size,bit) discrepancy. */
4372 if (align > BIGGEST_ALIGNMENT && Has_Alignment_Clause (gnat_entity))
4376 /* If a size was specified, take it into account. Otherwise
4377 use the RM size for records as the type size has already
4378 been adjusted to the alignment. */
4381 else if ((TREE_CODE (gnu_type) == RECORD_TYPE
4382 || TREE_CODE (gnu_type) == UNION_TYPE
4383 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
4384 && !TYPE_IS_FAT_POINTER_P (gnu_type))
4385 size = rm_size (gnu_type);
4387 size = TYPE_SIZE (gnu_type);
4389 /* Consider an alignment as suspicious if the alignment/size
4390 ratio is greater or equal to the byte/bit ratio. */
4391 if (host_integerp (size, 1)
4392 && align >= TREE_INT_CST_LOW (size) * BITS_PER_UNIT)
4393 post_error_ne ("?suspiciously large alignment specified for&",
4394 Expression (Alignment_Clause (gnat_entity)),
4398 else if (Is_Atomic (gnat_entity) && !gnu_size
4399 && host_integerp (TYPE_SIZE (gnu_type), 1)
4400 && integer_pow2p (TYPE_SIZE (gnu_type)))
4401 align = MIN (BIGGEST_ALIGNMENT,
4402 tree_low_cst (TYPE_SIZE (gnu_type), 1));
4403 else if (Is_Atomic (gnat_entity) && gnu_size
4404 && host_integerp (gnu_size, 1)
4405 && integer_pow2p (gnu_size))
4406 align = MIN (BIGGEST_ALIGNMENT, tree_low_cst (gnu_size, 1));
4408 /* See if we need to pad the type. If we did, and made a record,
4409 the name of the new type may be changed. So get it back for
4410 us when we make the new TYPE_DECL below. */
4411 if (gnu_size || align > 0)
4412 gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity,
4413 "PAD", true, definition, false);
4415 if (TREE_CODE (gnu_type) == RECORD_TYPE
4416 && TYPE_IS_PADDING_P (gnu_type))
4418 gnu_entity_id = TYPE_NAME (gnu_type);
4419 if (TREE_CODE (gnu_entity_id) == TYPE_DECL)
4420 gnu_entity_id = DECL_NAME (gnu_entity_id);
4423 set_rm_size (RM_Size (gnat_entity), gnu_type, gnat_entity);
4425 /* If we are at global level, GCC will have applied variable_size to
4426 the type, but that won't have done anything. So, if it's not
4427 a constant or self-referential, call elaborate_expression_1 to
4428 make a variable for the size rather than calculating it each time.
4429 Handle both the RM size and the actual size. */
4430 if (global_bindings_p ()
4431 && TYPE_SIZE (gnu_type)
4432 && !TREE_CONSTANT (TYPE_SIZE (gnu_type))
4433 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
4435 if (TREE_CODE (gnu_type) == RECORD_TYPE
4436 && operand_equal_p (TYPE_ADA_SIZE (gnu_type),
4437 TYPE_SIZE (gnu_type), 0))
4439 TYPE_SIZE (gnu_type)
4440 = elaborate_expression_1 (gnat_entity, gnat_entity,
4441 TYPE_SIZE (gnu_type),
4442 get_identifier ("SIZE"),
4444 SET_TYPE_ADA_SIZE (gnu_type, TYPE_SIZE (gnu_type));
4448 TYPE_SIZE (gnu_type)
4449 = elaborate_expression_1 (gnat_entity, gnat_entity,
4450 TYPE_SIZE (gnu_type),
4451 get_identifier ("SIZE"),
4454 /* ??? For now, store the size as a multiple of the alignment
4455 in bytes so that we can see the alignment from the tree. */
4456 TYPE_SIZE_UNIT (gnu_type)
4458 (MULT_EXPR, sizetype,
4459 elaborate_expression_1
4460 (gnat_entity, gnat_entity,
4461 build_binary_op (EXACT_DIV_EXPR, sizetype,
4462 TYPE_SIZE_UNIT (gnu_type),
4463 size_int (TYPE_ALIGN (gnu_type)
4465 get_identifier ("SIZE_A_UNIT"),
4467 size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT));
4469 if (TREE_CODE (gnu_type) == RECORD_TYPE)
4472 elaborate_expression_1 (gnat_entity,
4474 TYPE_ADA_SIZE (gnu_type),
4475 get_identifier ("RM_SIZE"),
4480 /* If this is a record type or subtype, call elaborate_expression_1 on
4481 any field position. Do this for both global and local types.
4482 Skip any fields that we haven't made trees for to avoid problems with
4483 class wide types. */
4484 if (IN (kind, Record_Kind))
4485 for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp);
4486 gnat_temp = Next_Entity (gnat_temp))
4487 if (Ekind (gnat_temp) == E_Component && present_gnu_tree (gnat_temp))
4489 tree gnu_field = get_gnu_tree (gnat_temp);
4491 /* ??? Unfortunately, GCC needs to be able to prove the
4492 alignment of this offset and if it's a variable, it can't.
4493 In GCC 3.4, we'll use DECL_OFFSET_ALIGN in some way, but
4494 right now, we have to put in an explicit multiply and
4495 divide by that value. */
4496 if (!CONTAINS_PLACEHOLDER_P (DECL_FIELD_OFFSET (gnu_field)))
4498 DECL_FIELD_OFFSET (gnu_field)
4500 (MULT_EXPR, sizetype,
4501 elaborate_expression_1
4502 (gnat_temp, gnat_temp,
4503 build_binary_op (EXACT_DIV_EXPR, sizetype,
4504 DECL_FIELD_OFFSET (gnu_field),
4505 size_int (DECL_OFFSET_ALIGN (gnu_field)
4507 get_identifier ("OFFSET"),
4509 size_int (DECL_OFFSET_ALIGN (gnu_field) / BITS_PER_UNIT));
4511 /* ??? The context of gnu_field is not necessarily gnu_type so
4512 the MULT_EXPR node built above may not be marked by the call
4513 to create_type_decl below. */
4514 if (global_bindings_p ())
4515 mark_visited (&DECL_FIELD_OFFSET (gnu_field));
4519 gnu_type = build_qualified_type (gnu_type,
4520 (TYPE_QUALS (gnu_type)
4521 | (TYPE_QUAL_VOLATILE
4522 * Treat_As_Volatile (gnat_entity))));
4524 if (Is_Atomic (gnat_entity))
4525 check_ok_for_atomic (gnu_type, gnat_entity, false);
4527 if (Present (Alignment_Clause (gnat_entity)))
4528 TYPE_USER_ALIGN (gnu_type) = 1;
4530 if (Universal_Aliasing (gnat_entity))
4531 TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (gnu_type)) = 1;
4534 gnu_decl = create_type_decl (gnu_entity_id, gnu_type, attr_list,
4535 !Comes_From_Source (gnat_entity),
4536 debug_info_p, gnat_entity);
4538 TREE_TYPE (gnu_decl) = gnu_type;
4541 if (IN (kind, Type_Kind) && !TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl)))
4543 gnu_type = TREE_TYPE (gnu_decl);
4545 /* If this is a derived type, relate its alias set to that of its parent
4546 to avoid troubles when a call to an inherited primitive is inlined in
4547 a context where a derived object is accessed. The inlined code works
4548 on the parent view so the resulting code may access the same object
4549 using both the parent and the derived alias sets, which thus have to
4550 conflict. As the same issue arises with component references, the
4551 parent alias set also has to conflict with composite types enclosing
4552 derived components. For instance, if we have:
4559 we want T to conflict with both D and R, in addition to R being a
4560 superset of D by record/component construction.
4562 One way to achieve this is to perform an alias set copy from the
4563 parent to the derived type. This is not quite appropriate, though,
4564 as we don't want separate derived types to conflict with each other:
4566 type I1 is new Integer;
4567 type I2 is new Integer;
4569 We want I1 and I2 to both conflict with Integer but we do not want
4570 I1 to conflict with I2, and an alias set copy on derivation would
4573 The option chosen is to make the alias set of the derived type a
4574 superset of that of its parent type. It trivially fulfills the
4575 simple requirement for the Integer derivation example above, and
4576 the component case as well by superset transitivity:
4579 R ----------> D ----------> T
4581 The language rules ensure the parent type is already frozen here. */
4582 if (Is_Derived_Type (gnat_entity))
4584 tree gnu_parent_type = gnat_to_gnu_type (Etype (gnat_entity));
4585 relate_alias_sets (gnu_type, gnu_parent_type, ALIAS_SET_SUPERSET);
4588 /* Back-annotate the Alignment of the type if not already in the
4589 tree. Likewise for sizes. */
4590 if (Unknown_Alignment (gnat_entity))
4591 Set_Alignment (gnat_entity,
4592 UI_From_Int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT));
4594 if (Unknown_Esize (gnat_entity) && TYPE_SIZE (gnu_type))
4596 /* If the size is self-referential, we annotate the maximum
4597 value of that size. */
4598 tree gnu_size = TYPE_SIZE (gnu_type);
4600 if (CONTAINS_PLACEHOLDER_P (gnu_size))
4601 gnu_size = max_size (gnu_size, true);
4603 Set_Esize (gnat_entity, annotate_value (gnu_size));
4605 if (type_annotate_only && Is_Tagged_Type (gnat_entity))
4607 /* In this mode the tag and the parent components are not
4608 generated by the front-end, so the sizes must be adjusted
4610 int size_offset, new_size;
4612 if (Is_Derived_Type (gnat_entity))
4615 = UI_To_Int (Esize (Etype (Base_Type (gnat_entity))));
4616 Set_Alignment (gnat_entity,
4617 Alignment (Etype (Base_Type (gnat_entity))));
4620 size_offset = POINTER_SIZE;
4622 new_size = UI_To_Int (Esize (gnat_entity)) + size_offset;
4623 Set_Esize (gnat_entity,
4624 UI_From_Int (((new_size + (POINTER_SIZE - 1))
4625 / POINTER_SIZE) * POINTER_SIZE));
4626 Set_RM_Size (gnat_entity, Esize (gnat_entity));
4630 if (Unknown_RM_Size (gnat_entity) && rm_size (gnu_type))
4631 Set_RM_Size (gnat_entity, annotate_value (rm_size (gnu_type)));
4634 if (!Comes_From_Source (gnat_entity) && DECL_P (gnu_decl))
4635 DECL_ARTIFICIAL (gnu_decl) = 1;
4637 if (!debug_info_p && DECL_P (gnu_decl)
4638 && TREE_CODE (gnu_decl) != FUNCTION_DECL
4639 && No (Renamed_Object (gnat_entity)))
4640 DECL_IGNORED_P (gnu_decl) = 1;
4642 /* If we haven't already, associate the ..._DECL node that we just made with
4643 the input GNAT entity node. */
4645 save_gnu_tree (gnat_entity, gnu_decl, false);
4647 /* If this is an enumeral or floating-point type, we were not able to set
4648 the bounds since they refer to the type. These bounds are always static.
4650 For enumeration types, also write debugging information and declare the
4651 enumeration literal table, if needed. */
4653 if ((kind == E_Enumeration_Type && Present (First_Literal (gnat_entity)))
4654 || (kind == E_Floating_Point_Type && !Vax_Float (gnat_entity)))
4656 tree gnu_scalar_type = gnu_type;
4658 /* If this is a padded type, we need to use the underlying type. */
4659 if (TREE_CODE (gnu_scalar_type) == RECORD_TYPE
4660 && TYPE_IS_PADDING_P (gnu_scalar_type))
4661 gnu_scalar_type = TREE_TYPE (TYPE_FIELDS (gnu_scalar_type));
4663 /* If this is a floating point type and we haven't set a floating
4664 point type yet, use this in the evaluation of the bounds. */
4665 if (!longest_float_type_node && kind == E_Floating_Point_Type)
4666 longest_float_type_node = gnu_type;
4668 TYPE_MIN_VALUE (gnu_scalar_type)
4669 = gnat_to_gnu (Type_Low_Bound (gnat_entity));
4670 TYPE_MAX_VALUE (gnu_scalar_type)
4671 = gnat_to_gnu (Type_High_Bound (gnat_entity));
4673 if (TREE_CODE (gnu_scalar_type) == ENUMERAL_TYPE)
4675 /* Since this has both a typedef and a tag, avoid outputting
4677 DECL_ARTIFICIAL (gnu_decl) = 1;
4678 rest_of_type_decl_compilation (gnu_decl);
4682 /* If we deferred processing of incomplete types, re-enable it. If there
4683 were no other disables and we have some to process, do so. */
4684 if (this_deferred && --defer_incomplete_level == 0)
4686 if (defer_incomplete_list)
4688 struct incomplete *incp, *next;
4690 /* We are back to level 0 for the deferring of incomplete types.
4691 But processing these incomplete types below may itself require
4692 deferring, so preserve what we have and restart from scratch. */
4693 incp = defer_incomplete_list;
4694 defer_incomplete_list = NULL;
4696 /* For finalization, however, all types must be complete so we
4697 cannot do the same because deferred incomplete types may end up
4698 referencing each other. Process them all recursively first. */
4699 defer_finalize_level++;
4701 for (; incp; incp = next)
4706 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4707 gnat_to_gnu_type (incp->full_type));
4711 defer_finalize_level--;
4714 /* All the deferred incomplete types have been processed so we can
4715 now proceed with the finalization of the deferred types. */
4716 if (defer_finalize_level == 0 && defer_finalize_list)
4721 for (i = 0; VEC_iterate (tree, defer_finalize_list, i, t); i++)
4722 rest_of_type_decl_compilation_no_defer (t);
4724 VEC_free (tree, heap, defer_finalize_list);
4728 /* If we are not defining this type, see if it's in the incomplete list.
4729 If so, handle that list entry now. */
4730 else if (!definition)
4732 struct incomplete *incp;
4734 for (incp = defer_incomplete_list; incp; incp = incp->next)
4735 if (incp->old_type && incp->full_type == gnat_entity)
4737 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4738 TREE_TYPE (gnu_decl));
4739 incp->old_type = NULL_TREE;
4746 if (Is_Packed_Array_Type (gnat_entity)
4747 && Is_Itype (Associated_Node_For_Itype (gnat_entity))
4748 && No (Freeze_Node (Associated_Node_For_Itype (gnat_entity)))
4749 && !present_gnu_tree (Associated_Node_For_Itype (gnat_entity)))
4750 gnat_to_gnu_entity (Associated_Node_For_Itype (gnat_entity), NULL_TREE, 0);
4755 /* Similar, but if the returned value is a COMPONENT_REF, return the
4759 gnat_to_gnu_field_decl (Entity_Id gnat_entity)
4761 tree gnu_field = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0);
4763 if (TREE_CODE (gnu_field) == COMPONENT_REF)
4764 gnu_field = TREE_OPERAND (gnu_field, 1);
4769 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return
4770 the GCC type corresponding to that entity. */
4773 gnat_to_gnu_type (Entity_Id gnat_entity)
4777 /* The back end never attempts to annotate generic types. */
4778 if (Is_Generic_Type (gnat_entity) && type_annotate_only)
4779 return void_type_node;
4781 gnu_decl = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0);
4782 gcc_assert (TREE_CODE (gnu_decl) == TYPE_DECL);
4784 return TREE_TYPE (gnu_decl);
4787 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return
4788 the unpadded version of the GCC type corresponding to that entity. */
4791 get_unpadded_type (Entity_Id gnat_entity)
4793 tree type = gnat_to_gnu_type (gnat_entity);
4795 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
4796 type = TREE_TYPE (TYPE_FIELDS (type));
4801 /* Wrap up compilation of DECL, a TYPE_DECL, possibly deferring it.
4802 Every TYPE_DECL generated for a type definition must be passed
4803 to this function once everything else has been done for it. */
4806 rest_of_type_decl_compilation (tree decl)
4808 /* We need to defer finalizing the type if incomplete types
4809 are being deferred or if they are being processed. */
4810 if (defer_incomplete_level || defer_finalize_level)
4811 VEC_safe_push (tree, heap, defer_finalize_list, decl);
4813 rest_of_type_decl_compilation_no_defer (decl);
4816 /* Same as above but without deferring the compilation. This
4817 function should not be invoked directly on a TYPE_DECL. */
4820 rest_of_type_decl_compilation_no_defer (tree decl)
4822 const int toplev = global_bindings_p ();
4823 tree t = TREE_TYPE (decl);
4825 rest_of_decl_compilation (decl, toplev, 0);
4827 /* Now process all the variants. This is needed for STABS. */
4828 for (t = TYPE_MAIN_VARIANT (t); t; t = TYPE_NEXT_VARIANT (t))
4830 if (t == TREE_TYPE (decl))
4833 if (!TYPE_STUB_DECL (t))
4834 TYPE_STUB_DECL (t) = create_type_stub_decl (DECL_NAME (decl), t);
4836 rest_of_type_compilation (t, toplev);
4840 /* Finalize any From_With_Type incomplete types. We do this after processing
4841 our compilation unit and after processing its spec, if this is a body. */
4844 finalize_from_with_types (void)
4846 struct incomplete *incp = defer_limited_with;
4847 struct incomplete *next;
4849 defer_limited_with = 0;
4850 for (; incp; incp = next)
4854 if (incp->old_type != 0)
4855 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4856 gnat_to_gnu_type (incp->full_type));
4861 /* Return the equivalent type to be used for GNAT_ENTITY, if it's a
4862 kind of type (such E_Task_Type) that has a different type which Gigi
4863 uses for its representation. If the type does not have a special type
4864 for its representation, return GNAT_ENTITY. If a type is supposed to
4865 exist, but does not, abort unless annotating types, in which case
4866 return Empty. If GNAT_ENTITY is Empty, return Empty. */
4869 Gigi_Equivalent_Type (Entity_Id gnat_entity)
4871 Entity_Id gnat_equiv = gnat_entity;
4873 if (No (gnat_entity))
4876 switch (Ekind (gnat_entity))
4878 case E_Class_Wide_Subtype:
4879 if (Present (Equivalent_Type (gnat_entity)))
4880 gnat_equiv = Equivalent_Type (gnat_entity);
4883 case E_Access_Protected_Subprogram_Type:
4884 case E_Anonymous_Access_Protected_Subprogram_Type:
4885 gnat_equiv = Equivalent_Type (gnat_entity);
4888 case E_Class_Wide_Type:
4889 gnat_equiv = ((Present (Equivalent_Type (gnat_entity)))
4890 ? Equivalent_Type (gnat_entity)
4891 : Root_Type (gnat_entity));
4895 case E_Task_Subtype:
4896 case E_Protected_Type:
4897 case E_Protected_Subtype:
4898 gnat_equiv = Corresponding_Record_Type (gnat_entity);
4905 gcc_assert (Present (gnat_equiv) || type_annotate_only);
4909 /* Return a GCC tree for a parameter corresponding to GNAT_PARAM and
4910 using MECH as its passing mechanism, to be placed in the parameter
4911 list built for GNAT_SUBPROG. Assume a foreign convention for the
4912 latter if FOREIGN is true. Also set CICO to true if the parameter
4913 must use the copy-in copy-out implementation mechanism.
4915 The returned tree is a PARM_DECL, except for those cases where no
4916 parameter needs to be actually passed to the subprogram; the type
4917 of this "shadow" parameter is then returned instead. */
4920 gnat_to_gnu_param (Entity_Id gnat_param, Mechanism_Type mech,
4921 Entity_Id gnat_subprog, bool foreign, bool *cico)
4923 tree gnu_param_name = get_entity_name (gnat_param);
4924 tree gnu_param_type = gnat_to_gnu_type (Etype (gnat_param));
4925 tree gnu_param_type_alt = NULL_TREE;
4926 bool in_param = (Ekind (gnat_param) == E_In_Parameter);
4927 /* The parameter can be indirectly modified if its address is taken. */
4928 bool ro_param = in_param && !Address_Taken (gnat_param);
4929 bool by_return = false, by_component_ptr = false, by_ref = false;
4932 /* Copy-return is used only for the first parameter of a valued procedure.
4933 It's a copy mechanism for which a parameter is never allocated. */
4934 if (mech == By_Copy_Return)
4936 gcc_assert (Ekind (gnat_param) == E_Out_Parameter);
4941 /* If this is either a foreign function or if the underlying type won't
4942 be passed by reference, strip off possible padding type. */
4943 if (TREE_CODE (gnu_param_type) == RECORD_TYPE
4944 && TYPE_IS_PADDING_P (gnu_param_type))
4946 tree unpadded_type = TREE_TYPE (TYPE_FIELDS (gnu_param_type));
4948 if (mech == By_Reference
4950 || (!must_pass_by_ref (unpadded_type)
4951 && (mech == By_Copy || !default_pass_by_ref (unpadded_type))))
4952 gnu_param_type = unpadded_type;
4955 /* If this is a read-only parameter, make a variant of the type that is
4956 read-only. ??? However, if this is an unconstrained array, that type
4957 can be very complex, so skip it for now. Likewise for any other
4958 self-referential type. */
4960 && TREE_CODE (gnu_param_type) != UNCONSTRAINED_ARRAY_TYPE
4961 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_param_type)))
4962 gnu_param_type = build_qualified_type (gnu_param_type,
4963 (TYPE_QUALS (gnu_param_type)
4964 | TYPE_QUAL_CONST));
4966 /* For foreign conventions, pass arrays as pointers to the element type.
4967 First check for unconstrained array and get the underlying array. */
4968 if (foreign && TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE)
4970 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_param_type))));
4972 /* VMS descriptors are themselves passed by reference. */
4973 if (mech == By_Short_Descriptor ||
4974 (mech == By_Descriptor && TARGET_ABI_OPEN_VMS && !TARGET_MALLOC64))
4976 = build_pointer_type (build_vms_descriptor32 (gnu_param_type,
4977 Mechanism (gnat_param),
4979 else if (mech == By_Descriptor)
4981 /* Build both a 32-bit and 64-bit descriptor, one of which will be
4982 chosen in fill_vms_descriptor. */
4984 = build_pointer_type (build_vms_descriptor32 (gnu_param_type,
4985 Mechanism (gnat_param),
4988 = build_pointer_type (build_vms_descriptor (gnu_param_type,
4989 Mechanism (gnat_param),
4993 /* Arrays are passed as pointers to element type for foreign conventions. */
4996 && TREE_CODE (gnu_param_type) == ARRAY_TYPE)
4998 /* Strip off any multi-dimensional entries, then strip
4999 off the last array to get the component type. */
5000 while (TREE_CODE (TREE_TYPE (gnu_param_type)) == ARRAY_TYPE
5001 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_param_type)))
5002 gnu_param_type = TREE_TYPE (gnu_param_type);
5004 by_component_ptr = true;
5005 gnu_param_type = TREE_TYPE (gnu_param_type);
5008 gnu_param_type = build_qualified_type (gnu_param_type,
5009 (TYPE_QUALS (gnu_param_type)
5010 | TYPE_QUAL_CONST));
5012 gnu_param_type = build_pointer_type (gnu_param_type);
5015 /* Fat pointers are passed as thin pointers for foreign conventions. */
5016 else if (foreign && TYPE_FAT_POINTER_P (gnu_param_type))
5018 = make_type_from_size (gnu_param_type, size_int (POINTER_SIZE), 0);
5020 /* If we must pass or were requested to pass by reference, do so.
5021 If we were requested to pass by copy, do so.
5022 Otherwise, for foreign conventions, pass In Out or Out parameters
5023 or aggregates by reference. For COBOL and Fortran, pass all
5024 integer and FP types that way too. For Convention Ada, use
5025 the standard Ada default. */
5026 else if (must_pass_by_ref (gnu_param_type)
5027 || mech == By_Reference
5030 && (!in_param || AGGREGATE_TYPE_P (gnu_param_type)))
5032 && (Convention (gnat_subprog) == Convention_Fortran
5033 || Convention (gnat_subprog) == Convention_COBOL)
5034 && (INTEGRAL_TYPE_P (gnu_param_type)
5035 || FLOAT_TYPE_P (gnu_param_type)))
5037 && default_pass_by_ref (gnu_param_type)))))
5039 gnu_param_type = build_reference_type (gnu_param_type);
5043 /* Pass In Out or Out parameters using copy-in copy-out mechanism. */
5047 if (mech == By_Copy && (by_ref || by_component_ptr))
5048 post_error ("?cannot pass & by copy", gnat_param);
5050 /* If this is an Out parameter that isn't passed by reference and isn't
5051 a pointer or aggregate, we don't make a PARM_DECL for it. Instead,
5052 it will be a VAR_DECL created when we process the procedure, so just
5053 return its type. For the special parameter of a valued procedure,
5056 An exception is made to cover the RM-6.4.1 rule requiring "by copy"
5057 Out parameters with discriminants or implicit initial values to be
5058 handled like In Out parameters. These type are normally built as
5059 aggregates, hence passed by reference, except for some packed arrays
5060 which end up encoded in special integer types.
5062 The exception we need to make is then for packed arrays of records
5063 with discriminants or implicit initial values. We have no light/easy
5064 way to check for the latter case, so we merely check for packed arrays
5065 of records. This may lead to useless copy-in operations, but in very
5066 rare cases only, as these would be exceptions in a set of already
5067 exceptional situations. */
5068 if (Ekind (gnat_param) == E_Out_Parameter
5071 || (mech != By_Descriptor
5072 && mech != By_Short_Descriptor
5073 && !POINTER_TYPE_P (gnu_param_type)
5074 && !AGGREGATE_TYPE_P (gnu_param_type)))
5075 && !(Is_Array_Type (Etype (gnat_param))
5076 && Is_Packed (Etype (gnat_param))
5077 && Is_Composite_Type (Component_Type (Etype (gnat_param)))))
5078 return gnu_param_type;
5080 gnu_param = create_param_decl (gnu_param_name, gnu_param_type,
5081 ro_param || by_ref || by_component_ptr);
5082 DECL_BY_REF_P (gnu_param) = by_ref;
5083 DECL_BY_COMPONENT_PTR_P (gnu_param) = by_component_ptr;
5084 DECL_BY_DESCRIPTOR_P (gnu_param) = (mech == By_Descriptor ||
5085 mech == By_Short_Descriptor);
5086 DECL_POINTS_TO_READONLY_P (gnu_param)
5087 = (ro_param && (by_ref || by_component_ptr));
5089 /* Save the alternate descriptor type, if any. */
5090 if (gnu_param_type_alt)
5091 SET_DECL_PARM_ALT_TYPE (gnu_param, gnu_param_type_alt);
5093 /* If no Mechanism was specified, indicate what we're using, then
5094 back-annotate it. */
5095 if (mech == Default)
5096 mech = (by_ref || by_component_ptr) ? By_Reference : By_Copy;
5098 Set_Mechanism (gnat_param, mech);
5102 /* Return true if DISCR1 and DISCR2 represent the same discriminant. */
5105 same_discriminant_p (Entity_Id discr1, Entity_Id discr2)
5107 while (Present (Corresponding_Discriminant (discr1)))
5108 discr1 = Corresponding_Discriminant (discr1);
5110 while (Present (Corresponding_Discriminant (discr2)))
5111 discr2 = Corresponding_Discriminant (discr2);
5114 Original_Record_Component (discr1) == Original_Record_Component (discr2);
5117 /* Return true if the array type specified by GNAT_TYPE and GNU_TYPE has
5118 a non-aliased component in the back-end sense. */
5121 array_type_has_nonaliased_component (Entity_Id gnat_type, tree gnu_type)
5123 /* If the type below this is a multi-array type, then
5124 this does not have aliased components. */
5125 if (TREE_CODE (TREE_TYPE (gnu_type)) == ARRAY_TYPE
5126 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type)))
5129 if (Has_Aliased_Components (gnat_type))
5132 return type_for_nonaliased_component_p (TREE_TYPE (gnu_type));
5135 /* Return true if GNAT_ADDRESS is a value known at compile-time. */
5138 compile_time_known_address_p (Node_Id gnat_address)
5140 /* Catch System'To_Address. */
5141 if (Nkind (gnat_address) == N_Unchecked_Type_Conversion)
5142 gnat_address = Expression (gnat_address);
5144 return Compile_Time_Known_Value (gnat_address);
5147 /* Given GNAT_ENTITY, elaborate all expressions that are required to
5148 be elaborated at the point of its definition, but do nothing else. */
5151 elaborate_entity (Entity_Id gnat_entity)
5153 switch (Ekind (gnat_entity))
5155 case E_Signed_Integer_Subtype:
5156 case E_Modular_Integer_Subtype:
5157 case E_Enumeration_Subtype:
5158 case E_Ordinary_Fixed_Point_Subtype:
5159 case E_Decimal_Fixed_Point_Subtype:
5160 case E_Floating_Point_Subtype:
5162 Node_Id gnat_lb = Type_Low_Bound (gnat_entity);
5163 Node_Id gnat_hb = Type_High_Bound (gnat_entity);
5165 /* ??? Tests for avoiding static constraint error expression
5166 is needed until the front stops generating bogus conversions
5167 on bounds of real types. */
5169 if (!Raises_Constraint_Error (gnat_lb))
5170 elaborate_expression (gnat_lb, gnat_entity, get_identifier ("L"),
5171 1, 0, Needs_Debug_Info (gnat_entity));
5172 if (!Raises_Constraint_Error (gnat_hb))
5173 elaborate_expression (gnat_hb, gnat_entity, get_identifier ("U"),
5174 1, 0, Needs_Debug_Info (gnat_entity));
5180 Node_Id full_definition = Declaration_Node (gnat_entity);
5181 Node_Id record_definition = Type_Definition (full_definition);
5183 /* If this is a record extension, go a level further to find the
5184 record definition. */
5185 if (Nkind (record_definition) == N_Derived_Type_Definition)
5186 record_definition = Record_Extension_Part (record_definition);
5190 case E_Record_Subtype:
5191 case E_Private_Subtype:
5192 case E_Limited_Private_Subtype:
5193 case E_Record_Subtype_With_Private:
5194 if (Is_Constrained (gnat_entity)
5195 && Has_Discriminants (Base_Type (gnat_entity))
5196 && Present (Discriminant_Constraint (gnat_entity)))
5198 Node_Id gnat_discriminant_expr;
5199 Entity_Id gnat_field;
5201 for (gnat_field = First_Discriminant (Base_Type (gnat_entity)),
5202 gnat_discriminant_expr
5203 = First_Elmt (Discriminant_Constraint (gnat_entity));
5204 Present (gnat_field);
5205 gnat_field = Next_Discriminant (gnat_field),
5206 gnat_discriminant_expr = Next_Elmt (gnat_discriminant_expr))
5207 /* ??? For now, ignore access discriminants. */
5208 if (!Is_Access_Type (Etype (Node (gnat_discriminant_expr))))
5209 elaborate_expression (Node (gnat_discriminant_expr),
5211 get_entity_name (gnat_field), 1, 0, 0);
5218 /* Mark GNAT_ENTITY as going out of scope at this point. Recursively mark
5219 any entities on its entity chain similarly. */
5222 mark_out_of_scope (Entity_Id gnat_entity)
5224 Entity_Id gnat_sub_entity;
5225 unsigned int kind = Ekind (gnat_entity);
5227 /* If this has an entity list, process all in the list. */
5228 if (IN (kind, Class_Wide_Kind) || IN (kind, Concurrent_Kind)
5229 || IN (kind, Private_Kind)
5230 || kind == E_Block || kind == E_Entry || kind == E_Entry_Family
5231 || kind == E_Function || kind == E_Generic_Function
5232 || kind == E_Generic_Package || kind == E_Generic_Procedure
5233 || kind == E_Loop || kind == E_Operator || kind == E_Package
5234 || kind == E_Package_Body || kind == E_Procedure
5235 || kind == E_Record_Type || kind == E_Record_Subtype
5236 || kind == E_Subprogram_Body || kind == E_Subprogram_Type)
5237 for (gnat_sub_entity = First_Entity (gnat_entity);
5238 Present (gnat_sub_entity);
5239 gnat_sub_entity = Next_Entity (gnat_sub_entity))
5240 if (Scope (gnat_sub_entity) == gnat_entity
5241 && gnat_sub_entity != gnat_entity)
5242 mark_out_of_scope (gnat_sub_entity);
5244 /* Now clear this if it has been defined, but only do so if it isn't
5245 a subprogram or parameter. We could refine this, but it isn't
5246 worth it. If this is statically allocated, it is supposed to
5247 hang around out of cope. */
5248 if (present_gnu_tree (gnat_entity) && !Is_Statically_Allocated (gnat_entity)
5249 && kind != E_Procedure && kind != E_Function && !IN (kind, Formal_Kind))
5251 save_gnu_tree (gnat_entity, NULL_TREE, true);
5252 save_gnu_tree (gnat_entity, error_mark_node, true);
5256 /* Relate the alias sets of GNU_NEW_TYPE and GNU_OLD_TYPE according to OP.
5257 If this is a multi-dimensional array type, do this recursively.
5260 - ALIAS_SET_COPY: the new set is made a copy of the old one.
5261 - ALIAS_SET_SUPERSET: the new set is made a superset of the old one.
5262 - ALIAS_SET_SUBSET: the new set is made a subset of the old one. */
5265 relate_alias_sets (tree gnu_new_type, tree gnu_old_type, enum alias_set_op op)
5267 /* Remove any padding from GNU_OLD_TYPE. It doesn't matter in the case
5268 of a one-dimensional array, since the padding has the same alias set
5269 as the field type, but if it's a multi-dimensional array, we need to
5270 see the inner types. */
5271 while (TREE_CODE (gnu_old_type) == RECORD_TYPE
5272 && (TYPE_JUSTIFIED_MODULAR_P (gnu_old_type)
5273 || TYPE_IS_PADDING_P (gnu_old_type)))
5274 gnu_old_type = TREE_TYPE (TYPE_FIELDS (gnu_old_type));
5276 /* Unconstrained array types are deemed incomplete and would thus be given
5277 alias set 0. Retrieve the underlying array type. */
5278 if (TREE_CODE (gnu_old_type) == UNCONSTRAINED_ARRAY_TYPE)
5280 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_old_type))));
5281 if (TREE_CODE (gnu_new_type) == UNCONSTRAINED_ARRAY_TYPE)
5283 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_new_type))));
5285 if (TREE_CODE (gnu_new_type) == ARRAY_TYPE
5286 && TREE_CODE (TREE_TYPE (gnu_new_type)) == ARRAY_TYPE
5287 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_new_type)))
5288 relate_alias_sets (TREE_TYPE (gnu_new_type), TREE_TYPE (gnu_old_type), op);
5292 case ALIAS_SET_COPY:
5293 /* The alias set shouldn't be copied between array types with different
5294 aliasing settings because this can break the aliasing relationship
5295 between the array type and its element type. */
5296 #ifndef ENABLE_CHECKING
5297 if (flag_strict_aliasing)
5299 gcc_assert (!(TREE_CODE (gnu_new_type) == ARRAY_TYPE
5300 && TREE_CODE (gnu_old_type) == ARRAY_TYPE
5301 && TYPE_NONALIASED_COMPONENT (gnu_new_type)
5302 != TYPE_NONALIASED_COMPONENT (gnu_old_type)));
5304 TYPE_ALIAS_SET (gnu_new_type) = get_alias_set (gnu_old_type);
5307 case ALIAS_SET_SUBSET:
5308 case ALIAS_SET_SUPERSET:
5310 alias_set_type old_set = get_alias_set (gnu_old_type);
5311 alias_set_type new_set = get_alias_set (gnu_new_type);
5313 /* Do nothing if the alias sets conflict. This ensures that we
5314 never call record_alias_subset several times for the same pair
5315 or at all for alias set 0. */
5316 if (!alias_sets_conflict_p (old_set, new_set))
5318 if (op == ALIAS_SET_SUBSET)
5319 record_alias_subset (old_set, new_set);
5321 record_alias_subset (new_set, old_set);
5330 record_component_aliases (gnu_new_type);
5333 /* Return a TREE_LIST describing the substitutions needed to reflect
5334 discriminant substitutions from GNAT_SUBTYPE to GNAT_TYPE and add
5335 them to GNU_LIST. If GNAT_TYPE is not specified, use the base type
5336 of GNAT_SUBTYPE. The substitutions can be in any order. TREE_PURPOSE
5337 gives the tree for the discriminant and TREE_VALUES is the replacement
5338 value. They are in the form of operands to substitute_in_expr.
5339 DEFINITION is as in gnat_to_gnu_entity. */
5342 substitution_list (Entity_Id gnat_subtype, Entity_Id gnat_type,
5343 tree gnu_list, bool definition)
5345 Entity_Id gnat_discrim;
5349 gnat_type = Implementation_Base_Type (gnat_subtype);
5351 if (Has_Discriminants (gnat_type))
5352 for (gnat_discrim = First_Stored_Discriminant (gnat_type),
5353 gnat_value = First_Elmt (Stored_Constraint (gnat_subtype));
5354 Present (gnat_discrim);
5355 gnat_discrim = Next_Stored_Discriminant (gnat_discrim),
5356 gnat_value = Next_Elmt (gnat_value))
5357 /* Ignore access discriminants. */
5358 if (!Is_Access_Type (Etype (Node (gnat_value))))
5359 gnu_list = tree_cons (gnat_to_gnu_field_decl (gnat_discrim),
5360 elaborate_expression
5361 (Node (gnat_value), gnat_subtype,
5362 get_entity_name (gnat_discrim), definition,
5369 /* Return true if the size represented by GNU_SIZE can be handled by an
5370 allocation. If STATIC_P is true, consider only what can be done with a
5371 static allocation. */
5374 allocatable_size_p (tree gnu_size, bool static_p)
5376 HOST_WIDE_INT our_size;
5378 /* If this is not a static allocation, the only case we want to forbid
5379 is an overflowing size. That will be converted into a raise a
5382 return !(TREE_CODE (gnu_size) == INTEGER_CST
5383 && TREE_OVERFLOW (gnu_size));
5385 /* Otherwise, we need to deal with both variable sizes and constant
5386 sizes that won't fit in a host int. We use int instead of HOST_WIDE_INT
5387 since assemblers may not like very large sizes. */
5388 if (!host_integerp (gnu_size, 1))
5391 our_size = tree_low_cst (gnu_size, 1);
5392 return (int) our_size == our_size;
5395 /* Prepend to ATTR_LIST an entry for an attribute with provided TYPE,
5396 NAME, ARGS and ERROR_POINT. */
5399 prepend_one_attribute_to (struct attrib ** attr_list,
5400 enum attr_type attr_type,
5403 Node_Id attr_error_point)
5405 struct attrib * attr = (struct attrib *) xmalloc (sizeof (struct attrib));
5407 attr->type = attr_type;
5408 attr->name = attr_name;
5409 attr->args = attr_args;
5410 attr->error_point = attr_error_point;
5412 attr->next = *attr_list;
5416 /* Prepend to ATTR_LIST the list of attributes for GNAT_ENTITY, if any. */
5419 prepend_attributes (Entity_Id gnat_entity, struct attrib ** attr_list)
5423 for (gnat_temp = First_Rep_Item (gnat_entity); Present (gnat_temp);
5424 gnat_temp = Next_Rep_Item (gnat_temp))
5425 if (Nkind (gnat_temp) == N_Pragma)
5427 tree gnu_arg0 = NULL_TREE, gnu_arg1 = NULL_TREE;
5428 Node_Id gnat_assoc = Pragma_Argument_Associations (gnat_temp);
5429 enum attr_type etype;
5431 if (Present (gnat_assoc) && Present (First (gnat_assoc))
5432 && Present (Next (First (gnat_assoc)))
5433 && (Nkind (Expression (Next (First (gnat_assoc))))
5434 == N_String_Literal))
5436 gnu_arg0 = get_identifier (TREE_STRING_POINTER
5439 (First (gnat_assoc))))));
5440 if (Present (Next (Next (First (gnat_assoc))))
5441 && (Nkind (Expression (Next (Next (First (gnat_assoc)))))
5442 == N_String_Literal))
5443 gnu_arg1 = get_identifier (TREE_STRING_POINTER
5447 (First (gnat_assoc)))))));
5450 switch (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_temp))))
5452 case Pragma_Machine_Attribute:
5453 etype = ATTR_MACHINE_ATTRIBUTE;
5456 case Pragma_Linker_Alias:
5457 etype = ATTR_LINK_ALIAS;
5460 case Pragma_Linker_Section:
5461 etype = ATTR_LINK_SECTION;
5464 case Pragma_Linker_Constructor:
5465 etype = ATTR_LINK_CONSTRUCTOR;
5468 case Pragma_Linker_Destructor:
5469 etype = ATTR_LINK_DESTRUCTOR;
5472 case Pragma_Weak_External:
5473 etype = ATTR_WEAK_EXTERNAL;
5476 case Pragma_Thread_Local_Storage:
5477 etype = ATTR_THREAD_LOCAL_STORAGE;
5485 /* Prepend to the list now. Make a list of the argument we might
5486 have, as GCC expects it. */
5487 prepend_one_attribute_to
5490 (gnu_arg1 != NULL_TREE)
5491 ? build_tree_list (NULL_TREE, gnu_arg1) : NULL_TREE,
5492 Present (Next (First (gnat_assoc)))
5493 ? Expression (Next (First (gnat_assoc))) : gnat_temp);
5497 /* Called when we need to protect a variable object using a save_expr. */
5500 maybe_variable (tree gnu_operand)
5502 if (TREE_CONSTANT (gnu_operand) || TREE_READONLY (gnu_operand)
5503 || TREE_CODE (gnu_operand) == SAVE_EXPR
5504 || TREE_CODE (gnu_operand) == NULL_EXPR)
5507 if (TREE_CODE (gnu_operand) == UNCONSTRAINED_ARRAY_REF)
5509 tree gnu_result = build1 (UNCONSTRAINED_ARRAY_REF,
5510 TREE_TYPE (gnu_operand),
5511 variable_size (TREE_OPERAND (gnu_operand, 0)));
5513 TREE_READONLY (gnu_result) = TREE_STATIC (gnu_result)
5514 = TYPE_READONLY (TREE_TYPE (TREE_TYPE (gnu_operand)));
5518 return variable_size (gnu_operand);
5521 /* Given a GNAT tree GNAT_EXPR, for an expression which is a value within a
5522 type definition (either a bound or a discriminant value) for GNAT_ENTITY,
5523 return the GCC tree to use for that expression. GNU_NAME is the
5524 qualification to use if an external name is appropriate and DEFINITION is
5525 true if this is a definition of GNAT_ENTITY. If NEED_VALUE is true, we
5526 need a result. Otherwise, we are just elaborating this for side-effects.
5527 If NEED_DEBUG is true we need the symbol for debugging purposes even if it
5528 isn't needed for code generation. */
5531 elaborate_expression (Node_Id gnat_expr, Entity_Id gnat_entity,
5532 tree gnu_name, bool definition, bool need_value,
5537 /* If we already elaborated this expression (e.g., it was involved
5538 in the definition of a private type), use the old value. */
5539 if (present_gnu_tree (gnat_expr))
5540 return get_gnu_tree (gnat_expr);
5542 /* If we don't need a value and this is static or a discriminant, we
5543 don't need to do anything. */
5544 else if (!need_value
5545 && (Is_OK_Static_Expression (gnat_expr)
5546 || (Nkind (gnat_expr) == N_Identifier
5547 && Ekind (Entity (gnat_expr)) == E_Discriminant)))
5550 /* Otherwise, convert this tree to its GCC equivalent. */
5552 = elaborate_expression_1 (gnat_expr, gnat_entity, gnat_to_gnu (gnat_expr),
5553 gnu_name, definition, need_debug);
5555 /* Save the expression in case we try to elaborate this entity again. Since
5556 it's not a DECL, don't check it. Don't save if it's a discriminant. */
5557 if (!CONTAINS_PLACEHOLDER_P (gnu_expr))
5558 save_gnu_tree (gnat_expr, gnu_expr, true);
5560 return need_value ? gnu_expr : error_mark_node;
5563 /* Similar, but take a GNU expression. */
5566 elaborate_expression_1 (Node_Id gnat_expr, Entity_Id gnat_entity,
5567 tree gnu_expr, tree gnu_name, bool definition,
5570 tree gnu_decl = NULL_TREE;
5571 /* Skip any conversions and simple arithmetics to see if the expression
5572 is a read-only variable.
5573 ??? This really should remain read-only, but we have to think about
5574 the typing of the tree here. */
5576 = skip_simple_arithmetic (remove_conversions (gnu_expr, true));
5577 bool expr_global = Is_Public (gnat_entity) || global_bindings_p ();
5580 /* In most cases, we won't see a naked FIELD_DECL here because a
5581 discriminant reference will have been replaced with a COMPONENT_REF
5582 when the type is being elaborated. However, there are some cases
5583 involving child types where we will. So convert it to a COMPONENT_REF
5584 here. We have to hope it will be at the highest level of the
5585 expression in these cases. */
5586 if (TREE_CODE (gnu_expr) == FIELD_DECL)
5587 gnu_expr = build3 (COMPONENT_REF, TREE_TYPE (gnu_expr),
5588 build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (gnu_expr)),
5589 gnu_expr, NULL_TREE);
5591 /* If GNU_EXPR is neither a placeholder nor a constant, nor a variable
5592 that is read-only, make a variable that is initialized to contain the
5593 bound when the package containing the definition is elaborated. If
5594 this entity is defined at top level and a bound or discriminant value
5595 isn't a constant or a reference to a discriminant, replace the bound
5596 by the variable; otherwise use a SAVE_EXPR if needed. Note that we
5597 rely here on the fact that an expression cannot contain both the
5598 discriminant and some other variable. */
5600 expr_variable = (!CONSTANT_CLASS_P (gnu_expr)
5601 && !(TREE_CODE (gnu_inner_expr) == VAR_DECL
5602 && (TREE_READONLY (gnu_inner_expr)
5603 || DECL_READONLY_ONCE_ELAB (gnu_inner_expr)))
5604 && !CONTAINS_PLACEHOLDER_P (gnu_expr));
5606 /* If this is a static expression or contains a discriminant, we don't
5607 need the variable for debugging (and can't elaborate anyway if a
5610 && (Is_OK_Static_Expression (gnat_expr)
5611 || CONTAINS_PLACEHOLDER_P (gnu_expr)))
5614 /* Now create the variable if we need it. */
5615 if (need_debug || (expr_variable && expr_global))
5617 = create_var_decl (create_concat_name (gnat_entity,
5618 IDENTIFIER_POINTER (gnu_name)),
5619 NULL_TREE, TREE_TYPE (gnu_expr), gnu_expr,
5620 !need_debug, Is_Public (gnat_entity),
5621 !definition, false, NULL, gnat_entity);
5623 /* We only need to use this variable if we are in global context since GCC
5624 can do the right thing in the local case. */
5625 if (expr_global && expr_variable)
5627 else if (!expr_variable)
5630 return maybe_variable (gnu_expr);
5633 /* Create a record type that contains a SIZE bytes long field of TYPE with a
5634 starting bit position so that it is aligned to ALIGN bits, and leaving at
5635 least ROOM bytes free before the field. BASE_ALIGN is the alignment the
5636 record is guaranteed to get. */
5639 make_aligning_type (tree type, unsigned int align, tree size,
5640 unsigned int base_align, int room)
5642 /* We will be crafting a record type with one field at a position set to be
5643 the next multiple of ALIGN past record'address + room bytes. We use a
5644 record placeholder to express record'address. */
5646 tree record_type = make_node (RECORD_TYPE);
5647 tree record = build0 (PLACEHOLDER_EXPR, record_type);
5650 = convert (sizetype, build_unary_op (ADDR_EXPR, NULL_TREE, record));
5652 /* The diagram below summarizes the shape of what we manipulate:
5654 <--------- pos ---------->
5655 { +------------+-------------+-----------------+
5656 record =>{ |############| ... | field (type) |
5657 { +------------+-------------+-----------------+
5658 |<-- room -->|<- voffset ->|<---- size ----->|
5661 record_addr vblock_addr
5663 Every length is in sizetype bytes there, except "pos" which has to be
5664 set as a bit position in the GCC tree for the record. */
5666 tree room_st = size_int (room);
5667 tree vblock_addr_st = size_binop (PLUS_EXPR, record_addr_st, room_st);
5668 tree voffset_st, pos, field;
5670 tree name = TYPE_NAME (type);
5672 if (TREE_CODE (name) == TYPE_DECL)
5673 name = DECL_NAME (name);
5675 TYPE_NAME (record_type) = concat_id_with_name (name, "_ALIGN");
5677 /* Compute VOFFSET and then POS. The next byte position multiple of some
5678 alignment after some address is obtained by "and"ing the alignment minus
5679 1 with the two's complement of the address. */
5681 voffset_st = size_binop (BIT_AND_EXPR,
5682 size_diffop (size_zero_node, vblock_addr_st),
5683 ssize_int ((align / BITS_PER_UNIT) - 1));
5685 /* POS = (ROOM + VOFFSET) * BIT_PER_UNIT, in bitsizetype. */
5687 pos = size_binop (MULT_EXPR,
5688 convert (bitsizetype,
5689 size_binop (PLUS_EXPR, room_st, voffset_st)),
5692 /* Craft the GCC record representation. We exceptionally do everything
5693 manually here because 1) our generic circuitry is not quite ready to
5694 handle the complex position/size expressions we are setting up, 2) we
5695 have a strong simplifying factor at hand: we know the maximum possible
5696 value of voffset, and 3) we have to set/reset at least the sizes in
5697 accordance with this maximum value anyway, as we need them to convey
5698 what should be "alloc"ated for this type.
5700 Use -1 as the 'addressable' indication for the field to prevent the
5701 creation of a bitfield. We don't need one, it would have damaging
5702 consequences on the alignment computation, and create_field_decl would
5703 make one without this special argument, for instance because of the
5704 complex position expression. */
5706 field = create_field_decl (get_identifier ("F"), type, record_type,
5708 TYPE_FIELDS (record_type) = field;
5710 TYPE_ALIGN (record_type) = base_align;
5711 TYPE_USER_ALIGN (record_type) = 1;
5713 TYPE_SIZE (record_type)
5714 = size_binop (PLUS_EXPR,
5715 size_binop (MULT_EXPR, convert (bitsizetype, size),
5717 bitsize_int (align + room * BITS_PER_UNIT));
5718 TYPE_SIZE_UNIT (record_type)
5719 = size_binop (PLUS_EXPR, size,
5720 size_int (room + align / BITS_PER_UNIT));
5722 SET_TYPE_MODE (record_type, BLKmode);
5724 relate_alias_sets (record_type, type, ALIAS_SET_COPY);
5728 /* Return the result of rounding T up to ALIGN. */
5730 static inline unsigned HOST_WIDE_INT
5731 round_up_to_align (unsigned HOST_WIDE_INT t, unsigned int align)
5739 /* TYPE is a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE that is being used
5740 as the field type of a packed record if IN_RECORD is true, or as the
5741 component type of a packed array if IN_RECORD is false. See if we can
5742 rewrite it either as a type that has a non-BLKmode, which we can pack
5743 tighter in the packed record case, or as a smaller type. If so, return
5744 the new type. If not, return the original type. */
5747 make_packable_type (tree type, bool in_record)
5749 unsigned HOST_WIDE_INT size = tree_low_cst (TYPE_SIZE (type), 1);
5750 unsigned HOST_WIDE_INT new_size;
5751 tree new_type, old_field, field_list = NULL_TREE;
5753 /* No point in doing anything if the size is zero. */
5757 new_type = make_node (TREE_CODE (type));
5759 /* Copy the name and flags from the old type to that of the new.
5760 Note that we rely on the pointer equality created here for
5761 TYPE_NAME to look through conversions in various places. */
5762 TYPE_NAME (new_type) = TYPE_NAME (type);
5763 TYPE_JUSTIFIED_MODULAR_P (new_type) = TYPE_JUSTIFIED_MODULAR_P (type);
5764 TYPE_CONTAINS_TEMPLATE_P (new_type) = TYPE_CONTAINS_TEMPLATE_P (type);
5765 if (TREE_CODE (type) == RECORD_TYPE)
5766 TYPE_IS_PADDING_P (new_type) = TYPE_IS_PADDING_P (type);
5768 /* If we are in a record and have a small size, set the alignment to
5769 try for an integral mode. Otherwise set it to try for a smaller
5770 type with BLKmode. */
5771 if (in_record && size <= MAX_FIXED_MODE_SIZE)
5773 TYPE_ALIGN (new_type) = ceil_alignment (size);
5774 new_size = round_up_to_align (size, TYPE_ALIGN (new_type));
5778 unsigned HOST_WIDE_INT align;
5780 /* Do not try to shrink the size if the RM size is not constant. */
5781 if (TYPE_CONTAINS_TEMPLATE_P (type)
5782 || !host_integerp (TYPE_ADA_SIZE (type), 1))
5785 /* Round the RM size up to a unit boundary to get the minimal size
5786 for a BLKmode record. Give up if it's already the size. */
5787 new_size = TREE_INT_CST_LOW (TYPE_ADA_SIZE (type));
5788 new_size = round_up_to_align (new_size, BITS_PER_UNIT);
5789 if (new_size == size)
5792 align = new_size & -new_size;
5793 TYPE_ALIGN (new_type) = MIN (TYPE_ALIGN (type), align);
5796 TYPE_USER_ALIGN (new_type) = 1;
5798 /* Now copy the fields, keeping the position and size as we don't want
5799 to change the layout by propagating the packedness downwards. */
5800 for (old_field = TYPE_FIELDS (type); old_field;
5801 old_field = TREE_CHAIN (old_field))
5803 tree new_field_type = TREE_TYPE (old_field);
5804 tree new_field, new_size;
5806 if ((TREE_CODE (new_field_type) == RECORD_TYPE
5807 || TREE_CODE (new_field_type) == UNION_TYPE
5808 || TREE_CODE (new_field_type) == QUAL_UNION_TYPE)
5809 && !TYPE_IS_FAT_POINTER_P (new_field_type)
5810 && host_integerp (TYPE_SIZE (new_field_type), 1))
5811 new_field_type = make_packable_type (new_field_type, true);
5813 /* However, for the last field in a not already packed record type
5814 that is of an aggregate type, we need to use the RM_Size in the
5815 packable version of the record type, see finish_record_type. */
5816 if (!TREE_CHAIN (old_field)
5817 && !TYPE_PACKED (type)
5818 && (TREE_CODE (new_field_type) == RECORD_TYPE
5819 || TREE_CODE (new_field_type) == UNION_TYPE
5820 || TREE_CODE (new_field_type) == QUAL_UNION_TYPE)
5821 && !TYPE_IS_FAT_POINTER_P (new_field_type)
5822 && !TYPE_CONTAINS_TEMPLATE_P (new_field_type)
5823 && TYPE_ADA_SIZE (new_field_type))
5824 new_size = TYPE_ADA_SIZE (new_field_type);
5826 new_size = DECL_SIZE (old_field);
5828 new_field = create_field_decl (DECL_NAME (old_field), new_field_type,
5829 new_type, TYPE_PACKED (type), new_size,
5830 bit_position (old_field),
5831 !DECL_NONADDRESSABLE_P (old_field));
5833 DECL_INTERNAL_P (new_field) = DECL_INTERNAL_P (old_field);
5834 SET_DECL_ORIGINAL_FIELD
5835 (new_field, (DECL_ORIGINAL_FIELD (old_field)
5836 ? DECL_ORIGINAL_FIELD (old_field) : old_field));
5838 if (TREE_CODE (new_type) == QUAL_UNION_TYPE)
5839 DECL_QUALIFIER (new_field) = DECL_QUALIFIER (old_field);
5841 TREE_CHAIN (new_field) = field_list;
5842 field_list = new_field;
5845 finish_record_type (new_type, nreverse (field_list), 2, true);
5846 relate_alias_sets (new_type, type, ALIAS_SET_COPY);
5848 /* If this is a padding record, we never want to make the size smaller
5849 than what was specified. For QUAL_UNION_TYPE, also copy the size. */
5850 if ((TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
5851 || TREE_CODE (type) == QUAL_UNION_TYPE)
5853 TYPE_SIZE (new_type) = TYPE_SIZE (type);
5854 TYPE_SIZE_UNIT (new_type) = TYPE_SIZE_UNIT (type);
5858 TYPE_SIZE (new_type) = bitsize_int (new_size);
5859 TYPE_SIZE_UNIT (new_type)
5860 = size_int ((new_size + BITS_PER_UNIT - 1) / BITS_PER_UNIT);
5863 if (!TYPE_CONTAINS_TEMPLATE_P (type))
5864 SET_TYPE_ADA_SIZE (new_type, TYPE_ADA_SIZE (type));
5866 compute_record_mode (new_type);
5868 /* Try harder to get a packable type if necessary, for example
5869 in case the record itself contains a BLKmode field. */
5870 if (in_record && TYPE_MODE (new_type) == BLKmode)
5871 SET_TYPE_MODE (new_type,
5872 mode_for_size_tree (TYPE_SIZE (new_type), MODE_INT, 1));
5874 /* If neither the mode nor the size has shrunk, return the old type. */
5875 if (TYPE_MODE (new_type) == BLKmode && new_size >= size)
5881 /* Ensure that TYPE has SIZE and ALIGN. Make and return a new padded type
5882 if needed. We have already verified that SIZE and TYPE are large enough.
5884 GNAT_ENTITY and NAME_TRAILER are used to name the resulting record and
5887 IS_USER_TYPE is true if we must complete the original type.
5889 DEFINITION is true if this type is being defined.
5891 SAME_RM_SIZE is true if the RM_Size of the resulting type is to be set
5892 to SIZE too; otherwise, it's set to the RM_Size of the original type. */
5895 maybe_pad_type (tree type, tree size, unsigned int align,
5896 Entity_Id gnat_entity, const char *name_trailer,
5897 bool is_user_type, bool definition, bool same_rm_size)
5899 tree orig_rm_size = same_rm_size ? NULL_TREE : rm_size (type);
5900 tree orig_size = TYPE_SIZE (type);
5901 unsigned int orig_align = align;
5904 /* If TYPE is a padded type, see if it agrees with any size and alignment
5905 we were given. If so, return the original type. Otherwise, strip
5906 off the padding, since we will either be returning the inner type
5907 or repadding it. If no size or alignment is specified, use that of
5908 the original padded type. */
5909 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
5912 || operand_equal_p (round_up (size,
5913 MAX (align, TYPE_ALIGN (type))),
5914 round_up (TYPE_SIZE (type),
5915 MAX (align, TYPE_ALIGN (type))),
5917 && (align == 0 || align == TYPE_ALIGN (type)))
5921 size = TYPE_SIZE (type);
5923 align = TYPE_ALIGN (type);
5925 type = TREE_TYPE (TYPE_FIELDS (type));
5926 orig_size = TYPE_SIZE (type);
5929 /* If the size is either not being changed or is being made smaller (which
5930 is not done here (and is only valid for bitfields anyway), show the size
5931 isn't changing. Likewise, clear the alignment if it isn't being
5932 changed. Then return if we aren't doing anything. */
5934 && (operand_equal_p (size, orig_size, 0)
5935 || (TREE_CODE (orig_size) == INTEGER_CST
5936 && tree_int_cst_lt (size, orig_size))))
5939 if (align == TYPE_ALIGN (type))
5942 if (align == 0 && !size)
5945 /* If requested, complete the original type and give it a name. */
5947 create_type_decl (get_entity_name (gnat_entity), type,
5948 NULL, !Comes_From_Source (gnat_entity),
5950 && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
5951 && DECL_IGNORED_P (TYPE_NAME (type))),
5954 /* We used to modify the record in place in some cases, but that could
5955 generate incorrect debugging information. So make a new record
5957 record = make_node (RECORD_TYPE);
5958 TYPE_IS_PADDING_P (record) = 1;
5960 if (Present (gnat_entity))
5961 TYPE_NAME (record) = create_concat_name (gnat_entity, name_trailer);
5963 TYPE_VOLATILE (record)
5964 = Present (gnat_entity) && Treat_As_Volatile (gnat_entity);
5966 TYPE_ALIGN (record) = align;
5968 TYPE_USER_ALIGN (record) = align;
5970 TYPE_SIZE (record) = size ? size : orig_size;
5971 TYPE_SIZE_UNIT (record)
5972 = convert (sizetype,
5973 size_binop (CEIL_DIV_EXPR, TYPE_SIZE (record),
5974 bitsize_unit_node));
5976 /* If we are changing the alignment and the input type is a record with
5977 BLKmode and a small constant size, try to make a form that has an
5978 integral mode. This might allow the padding record to also have an
5979 integral mode, which will be much more efficient. There is no point
5980 in doing so if a size is specified unless it is also a small constant
5981 size and it is incorrect to do so if we cannot guarantee that the mode
5982 will be naturally aligned since the field must always be addressable.
5984 ??? This might not always be a win when done for a stand-alone object:
5985 since the nominal and the effective type of the object will now have
5986 different modes, a VIEW_CONVERT_EXPR will be required for converting
5987 between them and it might be hard to overcome afterwards, including
5988 at the RTL level when the stand-alone object is accessed as a whole. */
5990 && TREE_CODE (type) == RECORD_TYPE
5991 && TYPE_MODE (type) == BLKmode
5992 && TREE_CODE (orig_size) == INTEGER_CST
5993 && !TREE_OVERFLOW (orig_size)
5994 && compare_tree_int (orig_size, MAX_FIXED_MODE_SIZE) <= 0
5996 || (TREE_CODE (size) == INTEGER_CST
5997 && compare_tree_int (size, MAX_FIXED_MODE_SIZE) <= 0)))
5999 tree packable_type = make_packable_type (type, true);
6000 if (TYPE_MODE (packable_type) != BLKmode
6001 && align >= TYPE_ALIGN (packable_type))
6002 type = packable_type;
6005 /* Now create the field with the original size. */
6006 field = create_field_decl (get_identifier ("F"), type, record, 0,
6007 orig_size, bitsize_zero_node, 1);
6008 DECL_INTERNAL_P (field) = 1;
6010 /* Do not finalize it until after the auxiliary record is built. */
6011 finish_record_type (record, field, 1, true);
6013 /* Set the same size for its RM_size if requested; otherwise reuse
6014 the RM_size of the original type. */
6015 SET_TYPE_ADA_SIZE (record, same_rm_size ? size : orig_rm_size);
6017 /* Unless debugging information isn't being written for the input type,
6018 write a record that shows what we are a subtype of and also make a
6019 variable that indicates our size, if still variable. */
6020 if (TYPE_NAME (record)
6021 && AGGREGATE_TYPE_P (type)
6022 && TREE_CODE (orig_size) != INTEGER_CST
6023 && !(TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
6024 && DECL_IGNORED_P (TYPE_NAME (type))))
6026 tree marker = make_node (RECORD_TYPE);
6027 tree name = TYPE_NAME (record);
6028 tree orig_name = TYPE_NAME (type);
6030 if (TREE_CODE (name) == TYPE_DECL)
6031 name = DECL_NAME (name);
6033 if (TREE_CODE (orig_name) == TYPE_DECL)
6034 orig_name = DECL_NAME (orig_name);
6036 TYPE_NAME (marker) = concat_id_with_name (name, "XVS");
6037 finish_record_type (marker,
6038 create_field_decl (orig_name, integer_type_node,
6039 marker, 0, NULL_TREE, NULL_TREE,
6043 add_parallel_type (TYPE_STUB_DECL (record), marker);
6045 if (size && TREE_CODE (size) != INTEGER_CST && definition)
6046 create_var_decl (concat_id_with_name (name, "XVZ"), NULL_TREE,
6047 sizetype, TYPE_SIZE_UNIT (record), false, false,
6048 false, false, NULL, gnat_entity);
6051 rest_of_record_type_compilation (record);
6053 /* If the size was widened explicitly, maybe give a warning. Take the
6054 original size as the maximum size of the input if there was an
6055 unconstrained record involved and round it up to the specified alignment,
6056 if one was specified. */
6057 if (CONTAINS_PLACEHOLDER_P (orig_size))
6058 orig_size = max_size (orig_size, true);
6061 orig_size = round_up (orig_size, align);
6063 if (size && Present (gnat_entity)
6064 && !operand_equal_p (size, orig_size, 0)
6065 && !(TREE_CODE (size) == INTEGER_CST
6066 && TREE_CODE (orig_size) == INTEGER_CST
6067 && tree_int_cst_lt (size, orig_size)))
6069 Node_Id gnat_error_node = Empty;
6071 if (Is_Packed_Array_Type (gnat_entity))
6072 gnat_entity = Original_Array_Type (gnat_entity);
6074 if ((Ekind (gnat_entity) == E_Component
6075 || Ekind (gnat_entity) == E_Discriminant)
6076 && Present (Component_Clause (gnat_entity)))
6077 gnat_error_node = Last_Bit (Component_Clause (gnat_entity));
6078 else if (Present (Size_Clause (gnat_entity)))
6079 gnat_error_node = Expression (Size_Clause (gnat_entity));
6081 /* Generate message only for entities that come from source, since
6082 if we have an entity created by expansion, the message will be
6083 generated for some other corresponding source entity. */
6084 if (Comes_From_Source (gnat_entity) && Present (gnat_error_node))
6085 post_error_ne_tree ("{^ }bits of & unused?", gnat_error_node,
6087 size_diffop (size, orig_size));
6089 else if (*name_trailer == 'C' && !Is_Internal (gnat_entity))
6090 post_error_ne_tree ("component of& padded{ by ^ bits}?",
6091 gnat_entity, gnat_entity,
6092 size_diffop (size, orig_size));
6098 /* Given a GNU tree and a GNAT list of choices, generate an expression to test
6099 the value passed against the list of choices. */
6102 choices_to_gnu (tree operand, Node_Id choices)
6106 tree result = integer_zero_node;
6107 tree this_test, low = 0, high = 0, single = 0;
6109 for (choice = First (choices); Present (choice); choice = Next (choice))
6111 switch (Nkind (choice))
6114 low = gnat_to_gnu (Low_Bound (choice));
6115 high = gnat_to_gnu (High_Bound (choice));
6117 /* There's no good type to use here, so we might as well use
6118 integer_type_node. */
6120 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6121 build_binary_op (GE_EXPR, integer_type_node,
6123 build_binary_op (LE_EXPR, integer_type_node,
6128 case N_Subtype_Indication:
6129 gnat_temp = Range_Expression (Constraint (choice));
6130 low = gnat_to_gnu (Low_Bound (gnat_temp));
6131 high = gnat_to_gnu (High_Bound (gnat_temp));
6134 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6135 build_binary_op (GE_EXPR, integer_type_node,
6137 build_binary_op (LE_EXPR, integer_type_node,
6142 case N_Expanded_Name:
6143 /* This represents either a subtype range, an enumeration
6144 literal, or a constant Ekind says which. If an enumeration
6145 literal or constant, fall through to the next case. */
6146 if (Ekind (Entity (choice)) != E_Enumeration_Literal
6147 && Ekind (Entity (choice)) != E_Constant)
6149 tree type = gnat_to_gnu_type (Entity (choice));
6151 low = TYPE_MIN_VALUE (type);
6152 high = TYPE_MAX_VALUE (type);
6155 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6156 build_binary_op (GE_EXPR, integer_type_node,
6158 build_binary_op (LE_EXPR, integer_type_node,
6163 /* ... fall through ... */
6165 case N_Character_Literal:
6166 case N_Integer_Literal:
6167 single = gnat_to_gnu (choice);
6168 this_test = build_binary_op (EQ_EXPR, integer_type_node, operand,
6172 case N_Others_Choice:
6173 this_test = integer_one_node;
6180 result = build_binary_op (TRUTH_ORIF_EXPR, integer_type_node,
6187 /* Adjust PACKED setting as passed to gnat_to_gnu_field for a field of
6188 type FIELD_TYPE to be placed in RECORD_TYPE. Return the result. */
6191 adjust_packed (tree field_type, tree record_type, int packed)
6193 /* If the field contains an item of variable size, we cannot pack it
6194 because we cannot create temporaries of non-fixed size in case
6195 we need to take the address of the field. See addressable_p and
6196 the notes on the addressability issues for further details. */
6197 if (is_variable_size (field_type))
6200 /* If the alignment of the record is specified and the field type
6201 is over-aligned, request Storage_Unit alignment for the field. */
6204 if (TYPE_ALIGN (field_type) > TYPE_ALIGN (record_type))
6213 /* Return a GCC tree for a field corresponding to GNAT_FIELD to be
6214 placed in GNU_RECORD_TYPE.
6216 PACKED is 1 if the enclosing record is packed, -1 if the enclosing
6217 record has Component_Alignment of Storage_Unit, -2 if the enclosing
6218 record has a specified alignment.
6220 DEFINITION is true if this field is for a record being defined. */
6223 gnat_to_gnu_field (Entity_Id gnat_field, tree gnu_record_type, int packed,
6226 tree gnu_field_id = get_entity_name (gnat_field);
6227 tree gnu_field_type = gnat_to_gnu_type (Etype (gnat_field));
6228 tree gnu_field, gnu_size, gnu_pos;
6229 bool needs_strict_alignment
6230 = (Is_Aliased (gnat_field) || Strict_Alignment (Etype (gnat_field))
6231 || Treat_As_Volatile (gnat_field));
6233 /* If this field requires strict alignment, we cannot pack it because
6234 it would very likely be under-aligned in the record. */
6235 if (needs_strict_alignment)
6238 packed = adjust_packed (gnu_field_type, gnu_record_type, packed);
6240 /* If a size is specified, use it. Otherwise, if the record type is packed,
6241 use the official RM size. See "Handling of Type'Size Values" in Einfo
6242 for further details. */
6243 if (Known_Static_Esize (gnat_field))
6244 gnu_size = validate_size (Esize (gnat_field), gnu_field_type,
6245 gnat_field, FIELD_DECL, false, true);
6246 else if (packed == 1)
6247 gnu_size = validate_size (RM_Size (Etype (gnat_field)), gnu_field_type,
6248 gnat_field, FIELD_DECL, false, true);
6250 gnu_size = NULL_TREE;
6252 /* If we have a specified size that's smaller than that of the field type,
6253 or a position is specified, and the field type is a record, see if we can
6254 get either an integral mode form of the type or a smaller form. If we
6255 can, show a size was specified for the field if there wasn't one already,
6256 so we know to make this a bitfield and avoid making things wider.
6258 Doing this is first useful if the record is packed because we may then
6259 place the field at a non-byte-aligned position and so achieve tighter
6262 This is in addition *required* if the field shares a byte with another
6263 field and the front-end lets the back-end handle the references, because
6264 GCC does not handle BLKmode bitfields properly.
6266 We avoid the transformation if it is not required or potentially useful,
6267 as it might entail an increase of the field's alignment and have ripple
6268 effects on the outer record type. A typical case is a field known to be
6269 byte aligned and not to share a byte with another field.
6271 Besides, we don't even look the possibility of a transformation in cases
6272 known to be in error already, for instance when an invalid size results
6273 from a component clause. */
6275 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
6276 && !TYPE_IS_FAT_POINTER_P (gnu_field_type)
6277 && host_integerp (TYPE_SIZE (gnu_field_type), 1)
6280 && (tree_int_cst_lt (gnu_size, TYPE_SIZE (gnu_field_type))
6281 || Present (Component_Clause (gnat_field))))))
6283 /* See what the alternate type and size would be. */
6284 tree gnu_packable_type = make_packable_type (gnu_field_type, true);
6286 bool has_byte_aligned_clause
6287 = Present (Component_Clause (gnat_field))
6288 && (UI_To_Int (Component_Bit_Offset (gnat_field))
6289 % BITS_PER_UNIT == 0);
6291 /* Compute whether we should avoid the substitution. */
6293 /* There is no point substituting if there is no change... */
6294 = (gnu_packable_type == gnu_field_type)
6295 /* ... nor when the field is known to be byte aligned and not to
6296 share a byte with another field. */
6297 || (has_byte_aligned_clause
6298 && value_factor_p (gnu_size, BITS_PER_UNIT))
6299 /* The size of an aliased field must be an exact multiple of the
6300 type's alignment, which the substitution might increase. Reject
6301 substitutions that would so invalidate a component clause when the
6302 specified position is byte aligned, as the change would have no
6303 real benefit from the packing standpoint anyway. */
6304 || (Is_Aliased (gnat_field)
6305 && has_byte_aligned_clause
6306 && !value_factor_p (gnu_size, TYPE_ALIGN (gnu_packable_type)));
6308 /* Substitute unless told otherwise. */
6311 gnu_field_type = gnu_packable_type;
6314 gnu_size = rm_size (gnu_field_type);
6318 /* If we are packing the record and the field is BLKmode, round the
6319 size up to a byte boundary. */
6320 if (packed && TYPE_MODE (gnu_field_type) == BLKmode && gnu_size)
6321 gnu_size = round_up (gnu_size, BITS_PER_UNIT);
6323 if (Present (Component_Clause (gnat_field)))
6325 gnu_pos = UI_To_gnu (Component_Bit_Offset (gnat_field), bitsizetype);
6326 gnu_size = validate_size (Esize (gnat_field), gnu_field_type,
6327 gnat_field, FIELD_DECL, false, true);
6329 /* Ensure the position does not overlap with the parent subtype,
6331 if (Present (Parent_Subtype (Underlying_Type (Scope (gnat_field)))))
6334 = gnat_to_gnu_type (Parent_Subtype
6335 (Underlying_Type (Scope (gnat_field))));
6337 if (TREE_CODE (TYPE_SIZE (gnu_parent)) == INTEGER_CST
6338 && tree_int_cst_lt (gnu_pos, TYPE_SIZE (gnu_parent)))
6341 ("offset of& must be beyond parent{, minimum allowed is ^}",
6342 First_Bit (Component_Clause (gnat_field)), gnat_field,
6343 TYPE_SIZE_UNIT (gnu_parent));
6347 /* If this field needs strict alignment, ensure the record is
6348 sufficiently aligned and that that position and size are
6349 consistent with the alignment. */
6350 if (needs_strict_alignment)
6352 TYPE_ALIGN (gnu_record_type)
6353 = MAX (TYPE_ALIGN (gnu_record_type), TYPE_ALIGN (gnu_field_type));
6356 && !operand_equal_p (gnu_size, TYPE_SIZE (gnu_field_type), 0))
6358 if (Is_Atomic (gnat_field) || Is_Atomic (Etype (gnat_field)))
6360 ("atomic field& must be natural size of type{ (^)}",
6361 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6362 TYPE_SIZE (gnu_field_type));
6364 else if (Is_Aliased (gnat_field))
6366 ("size of aliased field& must be ^ bits",
6367 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6368 TYPE_SIZE (gnu_field_type));
6370 else if (Strict_Alignment (Etype (gnat_field)))
6372 ("size of & with aliased or tagged components not ^ bits",
6373 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6374 TYPE_SIZE (gnu_field_type));
6376 gnu_size = NULL_TREE;
6379 if (!integer_zerop (size_binop
6380 (TRUNC_MOD_EXPR, gnu_pos,
6381 bitsize_int (TYPE_ALIGN (gnu_field_type)))))
6383 if (Is_Aliased (gnat_field))
6385 ("position of aliased field& must be multiple of ^ bits",
6386 First_Bit (Component_Clause (gnat_field)), gnat_field,
6387 TYPE_ALIGN (gnu_field_type));
6389 else if (Treat_As_Volatile (gnat_field))
6391 ("position of volatile field& must be multiple of ^ bits",
6392 First_Bit (Component_Clause (gnat_field)), gnat_field,
6393 TYPE_ALIGN (gnu_field_type));
6395 else if (Strict_Alignment (Etype (gnat_field)))
6397 ("position of & with aliased or tagged components not multiple of ^ bits",
6398 First_Bit (Component_Clause (gnat_field)), gnat_field,
6399 TYPE_ALIGN (gnu_field_type));
6404 gnu_pos = NULL_TREE;
6408 if (Is_Atomic (gnat_field))
6409 check_ok_for_atomic (gnu_field_type, gnat_field, false);
6412 /* If the record has rep clauses and this is the tag field, make a rep
6413 clause for it as well. */
6414 else if (Has_Specified_Layout (Scope (gnat_field))
6415 && Chars (gnat_field) == Name_uTag)
6417 gnu_pos = bitsize_zero_node;
6418 gnu_size = TYPE_SIZE (gnu_field_type);
6422 gnu_pos = NULL_TREE;
6424 /* We need to make the size the maximum for the type if it is
6425 self-referential and an unconstrained type. In that case, we can't
6426 pack the field since we can't make a copy to align it. */
6427 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
6429 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_field_type))
6430 && !Is_Constrained (Underlying_Type (Etype (gnat_field))))
6432 gnu_size = max_size (TYPE_SIZE (gnu_field_type), true);
6436 /* If a size is specified, adjust the field's type to it. */
6439 /* If the field's type is justified modular, we would need to remove
6440 the wrapper to (better) meet the layout requirements. However we
6441 can do so only if the field is not aliased to preserve the unique
6442 layout and if the prescribed size is not greater than that of the
6443 packed array to preserve the justification. */
6444 if (!needs_strict_alignment
6445 && TREE_CODE (gnu_field_type) == RECORD_TYPE
6446 && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type)
6447 && tree_int_cst_compare (gnu_size, TYPE_ADA_SIZE (gnu_field_type))
6449 gnu_field_type = TREE_TYPE (TYPE_FIELDS (gnu_field_type));
6452 = make_type_from_size (gnu_field_type, gnu_size,
6453 Has_Biased_Representation (gnat_field));
6454 gnu_field_type = maybe_pad_type (gnu_field_type, gnu_size, 0, gnat_field,
6455 "PAD", false, definition, true);
6458 /* Otherwise (or if there was an error), don't specify a position. */
6460 gnu_pos = NULL_TREE;
6462 gcc_assert (TREE_CODE (gnu_field_type) != RECORD_TYPE
6463 || !TYPE_CONTAINS_TEMPLATE_P (gnu_field_type));
6465 /* Now create the decl for the field. */
6466 gnu_field = create_field_decl (gnu_field_id, gnu_field_type, gnu_record_type,
6467 packed, gnu_size, gnu_pos,
6468 Is_Aliased (gnat_field));
6469 Sloc_to_locus (Sloc (gnat_field), &DECL_SOURCE_LOCATION (gnu_field));
6470 TREE_THIS_VOLATILE (gnu_field) = Treat_As_Volatile (gnat_field);
6472 if (Ekind (gnat_field) == E_Discriminant)
6473 DECL_DISCRIMINANT_NUMBER (gnu_field)
6474 = UI_To_gnu (Discriminant_Number (gnat_field), sizetype);
6479 /* Return true if TYPE is a type with variable size, a padding type with a
6480 field of variable size or is a record that has a field such a field. */
6483 is_variable_size (tree type)
6487 if (!TREE_CONSTANT (TYPE_SIZE (type)))
6490 if (TREE_CODE (type) == RECORD_TYPE
6491 && TYPE_IS_PADDING_P (type)
6492 && !TREE_CONSTANT (DECL_SIZE (TYPE_FIELDS (type))))
6495 if (TREE_CODE (type) != RECORD_TYPE
6496 && TREE_CODE (type) != UNION_TYPE
6497 && TREE_CODE (type) != QUAL_UNION_TYPE)
6500 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6501 if (is_variable_size (TREE_TYPE (field)))
6507 /* qsort comparer for the bit positions of two record components. */
6510 compare_field_bitpos (const PTR rt1, const PTR rt2)
6512 const_tree const field1 = * (const_tree const *) rt1;
6513 const_tree const field2 = * (const_tree const *) rt2;
6515 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
6517 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
6520 /* Return a GCC tree for a record type given a GNAT Component_List and a chain
6521 of GCC trees for fields that are in the record and have already been
6522 processed. When called from gnat_to_gnu_entity during the processing of a
6523 record type definition, the GCC nodes for the discriminants will be on
6524 the chain. The other calls to this function are recursive calls from
6525 itself for the Component_List of a variant and the chain is empty.
6527 PACKED is 1 if this is for a packed record, -1 if this is for a record
6528 with Component_Alignment of Storage_Unit, -2 if this is for a record
6529 with a specified alignment.
6531 DEFINITION is true if we are defining this record.
6533 P_GNU_REP_LIST, if nonzero, is a pointer to a list to which each field
6534 with a rep clause is to be added. If it is nonzero, that is all that
6535 should be done with such fields.
6537 CANCEL_ALIGNMENT, if true, means the alignment should be zeroed before
6538 laying out the record. This means the alignment only serves to force fields
6539 to be bitfields, but not require the record to be that aligned. This is
6542 ALL_REP, if true, means a rep clause was found for all the fields. This
6543 simplifies the logic since we know we're not in the mixed case.
6545 DO_NOT_FINALIZE, if true, means that the record type is expected to be
6546 modified afterwards so it will not be sent to the back-end for finalization.
6548 UNCHECKED_UNION, if true, means that we are building a type for a record
6549 with a Pragma Unchecked_Union.
6551 The processing of the component list fills in the chain with all of the
6552 fields of the record and then the record type is finished. */
6555 components_to_record (tree gnu_record_type, Node_Id component_list,
6556 tree gnu_field_list, int packed, bool definition,
6557 tree *p_gnu_rep_list, bool cancel_alignment,
6558 bool all_rep, bool do_not_finalize, bool unchecked_union)
6560 Node_Id component_decl;
6561 Entity_Id gnat_field;
6562 Node_Id variant_part;
6563 tree gnu_our_rep_list = NULL_TREE;
6564 tree gnu_field, gnu_last;
6565 bool layout_with_rep = false;
6566 bool all_rep_and_size = all_rep && TYPE_SIZE (gnu_record_type);
6568 /* For each variable within each component declaration create a GCC field
6569 and add it to the list, skipping any pragmas in the list. */
6570 if (Present (Component_Items (component_list)))
6571 for (component_decl = First_Non_Pragma (Component_Items (component_list));
6572 Present (component_decl);
6573 component_decl = Next_Non_Pragma (component_decl))
6575 gnat_field = Defining_Entity (component_decl);
6577 if (Chars (gnat_field) == Name_uParent)
6578 gnu_field = tree_last (TYPE_FIELDS (gnu_record_type));
6581 gnu_field = gnat_to_gnu_field (gnat_field, gnu_record_type,
6582 packed, definition);
6584 /* If this is the _Tag field, put it before any discriminants,
6585 instead of after them as is the case for all other fields. */
6586 if (Chars (gnat_field) == Name_uTag)
6587 gnu_field_list = chainon (gnu_field_list, gnu_field);
6590 TREE_CHAIN (gnu_field) = gnu_field_list;
6591 gnu_field_list = gnu_field;
6595 save_gnu_tree (gnat_field, gnu_field, false);
6598 /* At the end of the component list there may be a variant part. */
6599 variant_part = Variant_Part (component_list);
6601 /* We create a QUAL_UNION_TYPE for the variant part since the variants are
6602 mutually exclusive and should go in the same memory. To do this we need
6603 to treat each variant as a record whose elements are created from the
6604 component list for the variant. So here we create the records from the
6605 lists for the variants and put them all into the QUAL_UNION_TYPE.
6606 If this is an Unchecked_Union, we make a UNION_TYPE instead or
6607 use GNU_RECORD_TYPE if there are no fields so far. */
6608 if (Present (variant_part))
6610 tree gnu_discriminant = gnat_to_gnu (Name (variant_part));
6612 tree gnu_name = TYPE_NAME (gnu_record_type);
6614 = concat_id_with_name (get_identifier (Get_Name_String
6615 (Chars (Name (variant_part)))),
6617 tree gnu_union_type;
6618 tree gnu_union_name;
6619 tree gnu_union_field;
6620 tree gnu_variant_list = NULL_TREE;
6622 if (TREE_CODE (gnu_name) == TYPE_DECL)
6623 gnu_name = DECL_NAME (gnu_name);
6625 gnu_union_name = concat_id_with_name (gnu_name,
6626 IDENTIFIER_POINTER (gnu_var_name));
6628 /* Reuse an enclosing union if all fields are in the variant part
6629 and there is no representation clause on the record, to match
6630 the layout of C unions. There is an associated check below. */
6632 && TREE_CODE (gnu_record_type) == UNION_TYPE
6633 && !TYPE_PACKED (gnu_record_type))
6634 gnu_union_type = gnu_record_type;
6638 = make_node (unchecked_union ? UNION_TYPE : QUAL_UNION_TYPE);
6640 TYPE_NAME (gnu_union_type) = gnu_union_name;
6641 TYPE_ALIGN (gnu_union_type) = 0;
6642 TYPE_PACKED (gnu_union_type) = TYPE_PACKED (gnu_record_type);
6645 for (variant = First_Non_Pragma (Variants (variant_part));
6647 variant = Next_Non_Pragma (variant))
6649 tree gnu_variant_type = make_node (RECORD_TYPE);
6650 tree gnu_inner_name;
6653 Get_Variant_Encoding (variant);
6654 gnu_inner_name = get_identifier (Name_Buffer);
6655 TYPE_NAME (gnu_variant_type)
6656 = concat_id_with_name (gnu_union_name,
6657 IDENTIFIER_POINTER (gnu_inner_name));
6659 /* Set the alignment of the inner type in case we need to make
6660 inner objects into bitfields, but then clear it out
6661 so the record actually gets only the alignment required. */
6662 TYPE_ALIGN (gnu_variant_type) = TYPE_ALIGN (gnu_record_type);
6663 TYPE_PACKED (gnu_variant_type) = TYPE_PACKED (gnu_record_type);
6665 /* Similarly, if the outer record has a size specified and all fields
6666 have record rep clauses, we can propagate the size into the
6668 if (all_rep_and_size)
6670 TYPE_SIZE (gnu_variant_type) = TYPE_SIZE (gnu_record_type);
6671 TYPE_SIZE_UNIT (gnu_variant_type)
6672 = TYPE_SIZE_UNIT (gnu_record_type);
6675 /* Create the record type for the variant. Note that we defer
6676 finalizing it until after we are sure to actually use it. */
6677 components_to_record (gnu_variant_type, Component_List (variant),
6678 NULL_TREE, packed, definition,
6679 &gnu_our_rep_list, !all_rep_and_size, all_rep,
6680 true, unchecked_union);
6682 gnu_qual = choices_to_gnu (gnu_discriminant,
6683 Discrete_Choices (variant));
6685 Set_Present_Expr (variant, annotate_value (gnu_qual));
6687 /* If this is an Unchecked_Union and we have exactly one field,
6688 use this field directly to match the layout of C unions. */
6690 && TYPE_FIELDS (gnu_variant_type)
6691 && !TREE_CHAIN (TYPE_FIELDS (gnu_variant_type)))
6692 gnu_field = TYPE_FIELDS (gnu_variant_type);
6695 /* Deal with packedness like in gnat_to_gnu_field. */
6697 = adjust_packed (gnu_variant_type, gnu_record_type, packed);
6699 /* Finalize the record type now. We used to throw away
6700 empty records but we no longer do that because we need
6701 them to generate complete debug info for the variant;
6702 otherwise, the union type definition will be lacking
6703 the fields associated with these empty variants. */
6704 rest_of_record_type_compilation (gnu_variant_type);
6706 gnu_field = create_field_decl (gnu_inner_name, gnu_variant_type,
6707 gnu_union_type, field_packed,
6709 ? TYPE_SIZE (gnu_variant_type)
6712 ? bitsize_zero_node : 0),
6715 DECL_INTERNAL_P (gnu_field) = 1;
6717 if (!unchecked_union)
6718 DECL_QUALIFIER (gnu_field) = gnu_qual;
6721 TREE_CHAIN (gnu_field) = gnu_variant_list;
6722 gnu_variant_list = gnu_field;
6725 /* Only make the QUAL_UNION_TYPE if there are any non-empty variants. */
6726 if (gnu_variant_list)
6728 int union_field_packed;
6730 if (all_rep_and_size)
6732 TYPE_SIZE (gnu_union_type) = TYPE_SIZE (gnu_record_type);
6733 TYPE_SIZE_UNIT (gnu_union_type)
6734 = TYPE_SIZE_UNIT (gnu_record_type);
6737 finish_record_type (gnu_union_type, nreverse (gnu_variant_list),
6738 all_rep_and_size ? 1 : 0, false);
6740 /* If GNU_UNION_TYPE is our record type, it means we must have an
6741 Unchecked_Union with no fields. Verify that and, if so, just
6743 if (gnu_union_type == gnu_record_type)
6745 gcc_assert (unchecked_union
6747 && !gnu_our_rep_list);
6751 /* Deal with packedness like in gnat_to_gnu_field. */
6753 = adjust_packed (gnu_union_type, gnu_record_type, packed);
6756 = create_field_decl (gnu_var_name, gnu_union_type, gnu_record_type,
6758 all_rep ? TYPE_SIZE (gnu_union_type) : 0,
6759 all_rep ? bitsize_zero_node : 0, 0);
6761 DECL_INTERNAL_P (gnu_union_field) = 1;
6762 TREE_CHAIN (gnu_union_field) = gnu_field_list;
6763 gnu_field_list = gnu_union_field;
6767 /* Scan GNU_FIELD_LIST and see if any fields have rep clauses. If they
6768 do, pull them out and put them into GNU_OUR_REP_LIST. We have to do this
6769 in a separate pass since we want to handle the discriminants but can't
6770 play with them until we've used them in debugging data above.
6772 ??? Note: if we then reorder them, debugging information will be wrong,
6773 but there's nothing that can be done about this at the moment. */
6774 for (gnu_field = gnu_field_list, gnu_last = NULL_TREE; gnu_field; )
6776 if (DECL_FIELD_OFFSET (gnu_field))
6778 tree gnu_next = TREE_CHAIN (gnu_field);
6781 gnu_field_list = gnu_next;
6783 TREE_CHAIN (gnu_last) = gnu_next;
6785 TREE_CHAIN (gnu_field) = gnu_our_rep_list;
6786 gnu_our_rep_list = gnu_field;
6787 gnu_field = gnu_next;
6791 gnu_last = gnu_field;
6792 gnu_field = TREE_CHAIN (gnu_field);
6796 /* If we have any items in our rep'ed field list, it is not the case that all
6797 the fields in the record have rep clauses, and P_REP_LIST is nonzero,
6798 set it and ignore the items. */
6799 if (gnu_our_rep_list && p_gnu_rep_list && !all_rep)
6800 *p_gnu_rep_list = chainon (*p_gnu_rep_list, gnu_our_rep_list);
6801 else if (gnu_our_rep_list)
6803 /* Otherwise, sort the fields by bit position and put them into their
6804 own record if we have any fields without rep clauses. */
6806 = (gnu_field_list ? make_node (RECORD_TYPE) : gnu_record_type);
6807 int len = list_length (gnu_our_rep_list);
6808 tree *gnu_arr = (tree *) alloca (sizeof (tree) * len);
6811 for (i = 0, gnu_field = gnu_our_rep_list; gnu_field;
6812 gnu_field = TREE_CHAIN (gnu_field), i++)
6813 gnu_arr[i] = gnu_field;
6815 qsort (gnu_arr, len, sizeof (tree), compare_field_bitpos);
6817 /* Put the fields in the list in order of increasing position, which
6818 means we start from the end. */
6819 gnu_our_rep_list = NULL_TREE;
6820 for (i = len - 1; i >= 0; i--)
6822 TREE_CHAIN (gnu_arr[i]) = gnu_our_rep_list;
6823 gnu_our_rep_list = gnu_arr[i];
6824 DECL_CONTEXT (gnu_arr[i]) = gnu_rep_type;
6829 finish_record_type (gnu_rep_type, gnu_our_rep_list, 1, false);
6830 gnu_field = create_field_decl (get_identifier ("REP"), gnu_rep_type,
6831 gnu_record_type, 0, 0, 0, 1);
6832 DECL_INTERNAL_P (gnu_field) = 1;
6833 gnu_field_list = chainon (gnu_field_list, gnu_field);
6837 layout_with_rep = true;
6838 gnu_field_list = nreverse (gnu_our_rep_list);
6842 if (cancel_alignment)
6843 TYPE_ALIGN (gnu_record_type) = 0;
6845 finish_record_type (gnu_record_type, nreverse (gnu_field_list),
6846 layout_with_rep ? 1 : 0, do_not_finalize);
6849 /* Given GNU_SIZE, a GCC tree representing a size, return a Uint to be
6850 placed into an Esize, Component_Bit_Offset, or Component_Size value
6851 in the GNAT tree. */
6854 annotate_value (tree gnu_size)
6856 int len = TREE_CODE_LENGTH (TREE_CODE (gnu_size));
6858 Node_Ref_Or_Val ops[3], ret;
6861 struct tree_int_map **h = NULL;
6863 /* See if we've already saved the value for this node. */
6864 if (EXPR_P (gnu_size))
6866 struct tree_int_map in;
6867 if (!annotate_value_cache)
6868 annotate_value_cache = htab_create_ggc (512, tree_int_map_hash,
6869 tree_int_map_eq, 0);
6870 in.base.from = gnu_size;
6871 h = (struct tree_int_map **)
6872 htab_find_slot (annotate_value_cache, &in, INSERT);
6875 return (Node_Ref_Or_Val) (*h)->to;
6878 /* If we do not return inside this switch, TCODE will be set to the
6879 code to use for a Create_Node operand and LEN (set above) will be
6880 the number of recursive calls for us to make. */
6882 switch (TREE_CODE (gnu_size))
6885 if (TREE_OVERFLOW (gnu_size))
6888 /* This may have come from a conversion from some smaller type,
6889 so ensure this is in bitsizetype. */
6890 gnu_size = convert (bitsizetype, gnu_size);
6892 /* For negative values, use NEGATE_EXPR of the supplied value. */
6893 if (tree_int_cst_sgn (gnu_size) < 0)
6895 /* The ridiculous code below is to handle the case of the largest
6896 negative integer. */
6897 tree negative_size = size_diffop (bitsize_zero_node, gnu_size);
6898 bool adjust = false;
6901 if (TREE_OVERFLOW (negative_size))
6904 = size_binop (MINUS_EXPR, bitsize_zero_node,
6905 size_binop (PLUS_EXPR, gnu_size,
6910 temp = build1 (NEGATE_EXPR, bitsizetype, negative_size);
6912 temp = build2 (MINUS_EXPR, bitsizetype, temp, bitsize_one_node);
6914 return annotate_value (temp);
6917 if (!host_integerp (gnu_size, 1))
6920 size = tree_low_cst (gnu_size, 1);
6922 /* This peculiar test is to make sure that the size fits in an int
6923 on machines where HOST_WIDE_INT is not "int". */
6924 if (tree_low_cst (gnu_size, 1) == size)
6925 return UI_From_Int (size);
6930 /* The only case we handle here is a simple discriminant reference. */
6931 if (TREE_CODE (TREE_OPERAND (gnu_size, 0)) == PLACEHOLDER_EXPR
6932 && TREE_CODE (TREE_OPERAND (gnu_size, 1)) == FIELD_DECL
6933 && DECL_DISCRIMINANT_NUMBER (TREE_OPERAND (gnu_size, 1)))
6934 return Create_Node (Discrim_Val,
6935 annotate_value (DECL_DISCRIMINANT_NUMBER
6936 (TREE_OPERAND (gnu_size, 1))),
6941 CASE_CONVERT: case NON_LVALUE_EXPR:
6942 return annotate_value (TREE_OPERAND (gnu_size, 0));
6944 /* Now just list the operations we handle. */
6945 case COND_EXPR: tcode = Cond_Expr; break;
6946 case PLUS_EXPR: tcode = Plus_Expr; break;
6947 case MINUS_EXPR: tcode = Minus_Expr; break;
6948 case MULT_EXPR: tcode = Mult_Expr; break;
6949 case TRUNC_DIV_EXPR: tcode = Trunc_Div_Expr; break;
6950 case CEIL_DIV_EXPR: tcode = Ceil_Div_Expr; break;
6951 case FLOOR_DIV_EXPR: tcode = Floor_Div_Expr; break;
6952 case TRUNC_MOD_EXPR: tcode = Trunc_Mod_Expr; break;
6953 case CEIL_MOD_EXPR: tcode = Ceil_Mod_Expr; break;
6954 case FLOOR_MOD_EXPR: tcode = Floor_Mod_Expr; break;
6955 case EXACT_DIV_EXPR: tcode = Exact_Div_Expr; break;
6956 case NEGATE_EXPR: tcode = Negate_Expr; break;
6957 case MIN_EXPR: tcode = Min_Expr; break;
6958 case MAX_EXPR: tcode = Max_Expr; break;
6959 case ABS_EXPR: tcode = Abs_Expr; break;
6960 case TRUTH_ANDIF_EXPR: tcode = Truth_Andif_Expr; break;
6961 case TRUTH_ORIF_EXPR: tcode = Truth_Orif_Expr; break;
6962 case TRUTH_AND_EXPR: tcode = Truth_And_Expr; break;
6963 case TRUTH_OR_EXPR: tcode = Truth_Or_Expr; break;
6964 case TRUTH_XOR_EXPR: tcode = Truth_Xor_Expr; break;
6965 case TRUTH_NOT_EXPR: tcode = Truth_Not_Expr; break;
6966 case BIT_AND_EXPR: tcode = Bit_And_Expr; break;
6967 case LT_EXPR: tcode = Lt_Expr; break;
6968 case LE_EXPR: tcode = Le_Expr; break;
6969 case GT_EXPR: tcode = Gt_Expr; break;
6970 case GE_EXPR: tcode = Ge_Expr; break;
6971 case EQ_EXPR: tcode = Eq_Expr; break;
6972 case NE_EXPR: tcode = Ne_Expr; break;
6978 /* Now get each of the operands that's relevant for this code. If any
6979 cannot be expressed as a repinfo node, say we can't. */
6980 for (i = 0; i < 3; i++)
6983 for (i = 0; i < len; i++)
6985 ops[i] = annotate_value (TREE_OPERAND (gnu_size, i));
6986 if (ops[i] == No_Uint)
6990 ret = Create_Node (tcode, ops[0], ops[1], ops[2]);
6992 /* Save the result in the cache. */
6995 *h = GGC_NEW (struct tree_int_map);
6996 (*h)->base.from = gnu_size;
7003 /* Given GNAT_ENTITY, a record type, and GNU_TYPE, its corresponding
7004 GCC type, set Component_Bit_Offset and Esize to the position and size
7008 annotate_rep (Entity_Id gnat_entity, tree gnu_type)
7012 Entity_Id gnat_field;
7014 /* We operate by first making a list of all fields and their positions
7015 (we can get the sizes easily at any time) by a recursive call
7016 and then update all the sizes into the tree. */
7017 gnu_list = compute_field_positions (gnu_type, NULL_TREE,
7018 size_zero_node, bitsize_zero_node,
7021 for (gnat_field = First_Entity (gnat_entity); Present (gnat_field);
7022 gnat_field = Next_Entity (gnat_field))
7023 if ((Ekind (gnat_field) == E_Component
7024 || (Ekind (gnat_field) == E_Discriminant
7025 && !Is_Unchecked_Union (Scope (gnat_field)))))
7027 tree parent_offset = bitsize_zero_node;
7029 gnu_entry = purpose_member (gnat_to_gnu_field_decl (gnat_field),
7034 if (type_annotate_only && Is_Tagged_Type (gnat_entity))
7036 /* In this mode the tag and parent components have not been
7037 generated, so we add the appropriate offset to each
7038 component. For a component appearing in the current
7039 extension, the offset is the size of the parent. */
7040 if (Is_Derived_Type (gnat_entity)
7041 && Original_Record_Component (gnat_field) == gnat_field)
7043 = UI_To_gnu (Esize (Etype (Base_Type (gnat_entity))),
7046 parent_offset = bitsize_int (POINTER_SIZE);
7049 Set_Component_Bit_Offset
7052 (size_binop (PLUS_EXPR,
7053 bit_from_pos (TREE_PURPOSE (TREE_VALUE (gnu_entry)),
7054 TREE_VALUE (TREE_VALUE
7055 (TREE_VALUE (gnu_entry)))),
7058 Set_Esize (gnat_field,
7059 annotate_value (DECL_SIZE (TREE_PURPOSE (gnu_entry))));
7061 else if (Is_Tagged_Type (gnat_entity)
7062 && Is_Derived_Type (gnat_entity))
7064 /* If there is no gnu_entry, this is an inherited component whose
7065 position is the same as in the parent type. */
7066 Set_Component_Bit_Offset
7068 Component_Bit_Offset (Original_Record_Component (gnat_field)));
7069 Set_Esize (gnat_field,
7070 Esize (Original_Record_Component (gnat_field)));
7075 /* Scan all fields in GNU_TYPE and build entries where TREE_PURPOSE is the
7076 FIELD_DECL and TREE_VALUE a TREE_LIST with TREE_PURPOSE being the byte
7077 position and TREE_VALUE being a TREE_LIST with TREE_PURPOSE the value to be
7078 placed into DECL_OFFSET_ALIGN and TREE_VALUE the bit position. GNU_POS is
7079 to be added to the position, GNU_BITPOS to the bit position, OFFSET_ALIGN is
7080 the present value of DECL_OFFSET_ALIGN and GNU_LIST is a list of the entries
7084 compute_field_positions (tree gnu_type, tree gnu_list, tree gnu_pos,
7085 tree gnu_bitpos, unsigned int offset_align)
7088 tree gnu_result = gnu_list;
7090 for (gnu_field = TYPE_FIELDS (gnu_type); gnu_field;
7091 gnu_field = TREE_CHAIN (gnu_field))
7093 tree gnu_our_bitpos = size_binop (PLUS_EXPR, gnu_bitpos,
7094 DECL_FIELD_BIT_OFFSET (gnu_field));
7095 tree gnu_our_offset = size_binop (PLUS_EXPR, gnu_pos,
7096 DECL_FIELD_OFFSET (gnu_field));
7097 unsigned int our_offset_align
7098 = MIN (offset_align, DECL_OFFSET_ALIGN (gnu_field));
7101 = tree_cons (gnu_field,
7102 tree_cons (gnu_our_offset,
7103 tree_cons (size_int (our_offset_align),
7104 gnu_our_bitpos, NULL_TREE),
7108 if (DECL_INTERNAL_P (gnu_field))
7110 = compute_field_positions (TREE_TYPE (gnu_field), gnu_result,
7111 gnu_our_offset, gnu_our_bitpos,
7118 /* UINT_SIZE is a Uint giving the specified size for an object of GNU_TYPE
7119 corresponding to GNAT_OBJECT. If size is valid, return a tree corresponding
7120 to its value. Otherwise return 0. KIND is VAR_DECL is we are specifying
7121 the size for an object, TYPE_DECL for the size of a type, and FIELD_DECL
7122 for the size of a field. COMPONENT_P is true if we are being called
7123 to process the Component_Size of GNAT_OBJECT. This is used for error
7124 message handling and to indicate to use the object size of GNU_TYPE.
7125 ZERO_OK is true if a size of zero is permitted; if ZERO_OK is false,
7126 it means that a size of zero should be treated as an unspecified size. */
7129 validate_size (Uint uint_size, tree gnu_type, Entity_Id gnat_object,
7130 enum tree_code kind, bool component_p, bool zero_ok)
7132 Node_Id gnat_error_node;
7133 tree type_size, size;
7135 if (kind == VAR_DECL
7136 /* If a type needs strict alignment, a component of this type in
7137 a packed record cannot be packed and thus uses the type size. */
7138 || (kind == TYPE_DECL && Strict_Alignment (gnat_object)))
7139 type_size = TYPE_SIZE (gnu_type);
7141 type_size = rm_size (gnu_type);
7143 /* Find the node to use for errors. */
7144 if ((Ekind (gnat_object) == E_Component
7145 || Ekind (gnat_object) == E_Discriminant)
7146 && Present (Component_Clause (gnat_object)))
7147 gnat_error_node = Last_Bit (Component_Clause (gnat_object));
7148 else if (Present (Size_Clause (gnat_object)))
7149 gnat_error_node = Expression (Size_Clause (gnat_object));
7151 gnat_error_node = gnat_object;
7153 /* Return 0 if no size was specified, either because Esize was not Present or
7154 the specified size was zero. */
7155 if (No (uint_size) || uint_size == No_Uint)
7158 /* Get the size as a tree. Give an error if a size was specified, but cannot
7159 be represented as in sizetype. */
7160 size = UI_To_gnu (uint_size, bitsizetype);
7161 if (TREE_OVERFLOW (size))
7163 post_error_ne (component_p ? "component size of & is too large"
7164 : "size of & is too large",
7165 gnat_error_node, gnat_object);
7169 /* Ignore a negative size since that corresponds to our back-annotation.
7170 Also ignore a zero size unless a size clause exists. */
7171 else if (tree_int_cst_sgn (size) < 0 || (integer_zerop (size) && !zero_ok))
7174 /* The size of objects is always a multiple of a byte. */
7175 if (kind == VAR_DECL
7176 && !integer_zerop (size_binop (TRUNC_MOD_EXPR, size, bitsize_unit_node)))
7179 post_error_ne ("component size for& is not a multiple of Storage_Unit",
7180 gnat_error_node, gnat_object);
7182 post_error_ne ("size for& is not a multiple of Storage_Unit",
7183 gnat_error_node, gnat_object);
7187 /* If this is an integral type or a packed array type, the front-end has
7188 verified the size, so we need not do it here (which would entail
7189 checking against the bounds). However, if this is an aliased object, it
7190 may not be smaller than the type of the object. */
7191 if ((INTEGRAL_TYPE_P (gnu_type) || TYPE_IS_PACKED_ARRAY_TYPE_P (gnu_type))
7192 && !(kind == VAR_DECL && Is_Aliased (gnat_object)))
7195 /* If the object is a record that contains a template, add the size of
7196 the template to the specified size. */
7197 if (TREE_CODE (gnu_type) == RECORD_TYPE
7198 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
7199 size = size_binop (PLUS_EXPR, DECL_SIZE (TYPE_FIELDS (gnu_type)), size);
7201 /* Modify the size of the type to be that of the maximum size if it has a
7203 if (type_size && CONTAINS_PLACEHOLDER_P (type_size))
7204 type_size = max_size (type_size, true);
7206 /* If this is an access type or a fat pointer, the minimum size is that given
7207 by the smallest integral mode that's valid for pointers. */
7208 if ((TREE_CODE (gnu_type) == POINTER_TYPE) || TYPE_FAT_POINTER_P (gnu_type))
7210 enum machine_mode p_mode;
7212 for (p_mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
7213 !targetm.valid_pointer_mode (p_mode);
7214 p_mode = GET_MODE_WIDER_MODE (p_mode))
7217 type_size = bitsize_int (GET_MODE_BITSIZE (p_mode));
7220 /* If the size of the object is a constant, the new size must not be
7222 if (TREE_CODE (type_size) != INTEGER_CST
7223 || TREE_OVERFLOW (type_size)
7224 || tree_int_cst_lt (size, type_size))
7228 ("component size for& too small{, minimum allowed is ^}",
7229 gnat_error_node, gnat_object, type_size);
7231 post_error_ne_tree ("size for& too small{, minimum allowed is ^}",
7232 gnat_error_node, gnat_object, type_size);
7234 if (kind == VAR_DECL && !component_p
7235 && TREE_CODE (rm_size (gnu_type)) == INTEGER_CST
7236 && !tree_int_cst_lt (size, rm_size (gnu_type)))
7237 post_error_ne_tree_2
7238 ("\\size of ^ is not a multiple of alignment (^ bits)",
7239 gnat_error_node, gnat_object, rm_size (gnu_type),
7240 TYPE_ALIGN (gnu_type));
7242 else if (INTEGRAL_TYPE_P (gnu_type))
7243 post_error_ne ("\\size would be legal if & were not aliased!",
7244 gnat_error_node, gnat_object);
7252 /* Similarly, but both validate and process a value of RM_Size. This
7253 routine is only called for types. */
7256 set_rm_size (Uint uint_size, tree gnu_type, Entity_Id gnat_entity)
7258 /* Only give an error if a Value_Size clause was explicitly given.
7259 Otherwise, we'd be duplicating an error on the Size clause. */
7260 Node_Id gnat_attr_node
7261 = Get_Attribute_Definition_Clause (gnat_entity, Attr_Value_Size);
7262 tree old_size = rm_size (gnu_type);
7265 /* Get the size as a tree. Do nothing if none was specified, either
7266 because RM_Size was not Present or if the specified size was zero.
7267 Give an error if a size was specified, but cannot be represented as
7269 if (No (uint_size) || uint_size == No_Uint)
7272 size = UI_To_gnu (uint_size, bitsizetype);
7273 if (TREE_OVERFLOW (size))
7275 if (Present (gnat_attr_node))
7276 post_error_ne ("Value_Size of & is too large", gnat_attr_node,
7282 /* Ignore a negative size since that corresponds to our back-annotation.
7283 Also ignore a zero size unless a size clause exists, a Value_Size
7284 clause exists, or this is an integer type, in which case the
7285 front end will have always set it. */
7286 else if (tree_int_cst_sgn (size) < 0
7287 || (integer_zerop (size) && No (gnat_attr_node)
7288 && !Has_Size_Clause (gnat_entity)
7289 && !Is_Discrete_Or_Fixed_Point_Type (gnat_entity)))
7292 /* If the old size is self-referential, get the maximum size. */
7293 if (CONTAINS_PLACEHOLDER_P (old_size))
7294 old_size = max_size (old_size, true);
7296 /* If the size of the object is a constant, the new size must not be
7297 smaller (the front end checks this for scalar types). */
7298 if (TREE_CODE (old_size) != INTEGER_CST
7299 || TREE_OVERFLOW (old_size)
7300 || (AGGREGATE_TYPE_P (gnu_type)
7301 && tree_int_cst_lt (size, old_size)))
7303 if (Present (gnat_attr_node))
7305 ("Value_Size for& too small{, minimum allowed is ^}",
7306 gnat_attr_node, gnat_entity, old_size);
7311 /* Otherwise, set the RM_Size. */
7312 if (TREE_CODE (gnu_type) == INTEGER_TYPE
7313 && Is_Discrete_Or_Fixed_Point_Type (gnat_entity))
7314 TYPE_RM_SIZE_NUM (gnu_type) = size;
7315 else if (TREE_CODE (gnu_type) == ENUMERAL_TYPE
7316 || TREE_CODE (gnu_type) == BOOLEAN_TYPE)
7317 TYPE_RM_SIZE_NUM (gnu_type) = size;
7318 else if ((TREE_CODE (gnu_type) == RECORD_TYPE
7319 || TREE_CODE (gnu_type) == UNION_TYPE
7320 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
7321 && !TYPE_IS_FAT_POINTER_P (gnu_type))
7322 SET_TYPE_ADA_SIZE (gnu_type, size);
7325 /* Given a type TYPE, return a new type whose size is appropriate for SIZE.
7326 If TYPE is the best type, return it. Otherwise, make a new type. We
7327 only support new integral and pointer types. FOR_BIASED is true if
7328 we are making a biased type. */
7331 make_type_from_size (tree type, tree size_tree, bool for_biased)
7333 unsigned HOST_WIDE_INT size;
7337 /* If size indicates an error, just return TYPE to avoid propagating
7338 the error. Likewise if it's too large to represent. */
7339 if (!size_tree || !host_integerp (size_tree, 1))
7342 size = tree_low_cst (size_tree, 1);
7344 switch (TREE_CODE (type))
7349 biased_p = (TREE_CODE (type) == INTEGER_TYPE
7350 && TYPE_BIASED_REPRESENTATION_P (type));
7352 /* Only do something if the type is not a packed array type and
7353 doesn't already have the proper size. */
7354 if (TYPE_PACKED_ARRAY_TYPE_P (type)
7355 || (TYPE_PRECISION (type) == size && biased_p == for_biased))
7358 biased_p |= for_biased;
7359 size = MIN (size, LONG_LONG_TYPE_SIZE);
7361 if (TYPE_UNSIGNED (type) || biased_p)
7362 new_type = make_unsigned_type (size);
7364 new_type = make_signed_type (size);
7365 TREE_TYPE (new_type) = TREE_TYPE (type) ? TREE_TYPE (type) : type;
7366 TYPE_MIN_VALUE (new_type)
7367 = convert (TREE_TYPE (new_type), TYPE_MIN_VALUE (type));
7368 TYPE_MAX_VALUE (new_type)
7369 = convert (TREE_TYPE (new_type), TYPE_MAX_VALUE (type));
7370 /* Propagate the name to avoid creating a fake subrange type. */
7371 if (TYPE_NAME (type))
7373 if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL)
7374 TYPE_NAME (new_type) = DECL_NAME (TYPE_NAME (type));
7376 TYPE_NAME (new_type) = TYPE_NAME (type);
7378 TYPE_BIASED_REPRESENTATION_P (new_type) = biased_p;
7379 TYPE_RM_SIZE_NUM (new_type) = bitsize_int (size);
7383 /* Do something if this is a fat pointer, in which case we
7384 may need to return the thin pointer. */
7385 if (TYPE_IS_FAT_POINTER_P (type) && size < POINTER_SIZE * 2)
7387 enum machine_mode p_mode = mode_for_size (size, MODE_INT, 0);
7388 if (!targetm.valid_pointer_mode (p_mode))
7391 build_pointer_type_for_mode
7392 (TYPE_OBJECT_RECORD_TYPE (TYPE_UNCONSTRAINED_ARRAY (type)),
7398 /* Only do something if this is a thin pointer, in which case we
7399 may need to return the fat pointer. */
7400 if (TYPE_THIN_POINTER_P (type) && size >= POINTER_SIZE * 2)
7402 build_pointer_type (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)));
7412 /* ALIGNMENT is a Uint giving the alignment specified for GNAT_ENTITY,
7413 a type or object whose present alignment is ALIGN. If this alignment is
7414 valid, return it. Otherwise, give an error and return ALIGN. */
7417 validate_alignment (Uint alignment, Entity_Id gnat_entity, unsigned int align)
7419 unsigned int max_allowed_alignment = get_target_maximum_allowed_alignment ();
7420 unsigned int new_align;
7421 Node_Id gnat_error_node;
7423 /* Don't worry about checking alignment if alignment was not specified
7424 by the source program and we already posted an error for this entity. */
7425 if (Error_Posted (gnat_entity) && !Has_Alignment_Clause (gnat_entity))
7428 /* Post the error on the alignment clause if any. */
7429 if (Present (Alignment_Clause (gnat_entity)))
7430 gnat_error_node = Expression (Alignment_Clause (gnat_entity));
7432 gnat_error_node = gnat_entity;
7434 /* Within GCC, an alignment is an integer, so we must make sure a value is
7435 specified that fits in that range. Also, there is an upper bound to
7436 alignments we can support/allow. */
7437 if (!UI_Is_In_Int_Range (alignment)
7438 || ((new_align = UI_To_Int (alignment)) > max_allowed_alignment))
7439 post_error_ne_num ("largest supported alignment for& is ^",
7440 gnat_error_node, gnat_entity, max_allowed_alignment);
7441 else if (!(Present (Alignment_Clause (gnat_entity))
7442 && From_At_Mod (Alignment_Clause (gnat_entity)))
7443 && new_align * BITS_PER_UNIT < align)
7444 post_error_ne_num ("alignment for& must be at least ^",
7445 gnat_error_node, gnat_entity,
7446 align / BITS_PER_UNIT);
7449 new_align = (new_align > 0 ? new_align * BITS_PER_UNIT : 1);
7450 if (new_align > align)
7457 /* Return the smallest alignment not less than SIZE. */
7460 ceil_alignment (unsigned HOST_WIDE_INT size)
7462 return (unsigned int) 1 << (floor_log2 (size - 1) + 1);
7465 /* Verify that OBJECT, a type or decl, is something we can implement
7466 atomically. If not, give an error for GNAT_ENTITY. COMP_P is true
7467 if we require atomic components. */
7470 check_ok_for_atomic (tree object, Entity_Id gnat_entity, bool comp_p)
7472 Node_Id gnat_error_point = gnat_entity;
7474 enum machine_mode mode;
7478 /* There are three case of what OBJECT can be. It can be a type, in which
7479 case we take the size, alignment and mode from the type. It can be a
7480 declaration that was indirect, in which case the relevant values are
7481 that of the type being pointed to, or it can be a normal declaration,
7482 in which case the values are of the decl. The code below assumes that
7483 OBJECT is either a type or a decl. */
7484 if (TYPE_P (object))
7486 mode = TYPE_MODE (object);
7487 align = TYPE_ALIGN (object);
7488 size = TYPE_SIZE (object);
7490 else if (DECL_BY_REF_P (object))
7492 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (object)));
7493 align = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (object)));
7494 size = TYPE_SIZE (TREE_TYPE (TREE_TYPE (object)));
7498 mode = DECL_MODE (object);
7499 align = DECL_ALIGN (object);
7500 size = DECL_SIZE (object);
7503 /* Consider all floating-point types atomic and any types that that are
7504 represented by integers no wider than a machine word. */
7505 if (GET_MODE_CLASS (mode) == MODE_FLOAT
7506 || ((GET_MODE_CLASS (mode) == MODE_INT
7507 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
7508 && GET_MODE_BITSIZE (mode) <= BITS_PER_WORD))
7511 /* For the moment, also allow anything that has an alignment equal
7512 to its size and which is smaller than a word. */
7513 if (size && TREE_CODE (size) == INTEGER_CST
7514 && compare_tree_int (size, align) == 0
7515 && align <= BITS_PER_WORD)
7518 for (gnat_node = First_Rep_Item (gnat_entity); Present (gnat_node);
7519 gnat_node = Next_Rep_Item (gnat_node))
7521 if (!comp_p && Nkind (gnat_node) == N_Pragma
7522 && (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node)))
7524 gnat_error_point = First (Pragma_Argument_Associations (gnat_node));
7525 else if (comp_p && Nkind (gnat_node) == N_Pragma
7526 && (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node)))
7527 == Pragma_Atomic_Components))
7528 gnat_error_point = First (Pragma_Argument_Associations (gnat_node));
7532 post_error_ne ("atomic access to component of & cannot be guaranteed",
7533 gnat_error_point, gnat_entity);
7535 post_error_ne ("atomic access to & cannot be guaranteed",
7536 gnat_error_point, gnat_entity);
7539 /* Check if FTYPE1 and FTYPE2, two potentially different function type nodes,
7540 have compatible signatures so that a call using one type may be safely
7541 issued if the actual target function type is the other. Return 1 if it is
7542 the case, 0 otherwise, and post errors on the incompatibilities.
7544 This is used when an Ada subprogram is mapped onto a GCC builtin, to ensure
7545 that calls to the subprogram will have arguments suitable for the later
7546 underlying builtin expansion. */
7549 compatible_signatures_p (tree ftype1, tree ftype2)
7551 /* As of now, we only perform very trivial tests and consider it's the
7552 programmer's responsibility to ensure the type correctness in the Ada
7553 declaration, as in the regular Import cases.
7555 Mismatches typically result in either error messages from the builtin
7556 expander, internal compiler errors, or in a real call sequence. This
7557 should be refined to issue diagnostics helping error detection and
7560 /* Almost fake test, ensuring a use of each argument. */
7561 if (ftype1 == ftype2)
7567 /* Given a type T, a FIELD_DECL F, and a replacement value R, return a
7568 type with all size expressions that contain F in a PLACEHOLDER_EXPR
7569 updated by replacing F with R.
7571 The function doesn't update the layout of the type, i.e. it assumes
7572 that the substitution is purely formal. That's why the replacement
7573 value R must itself contain a PLACEHOLDER_EXPR. */
7576 substitute_in_type (tree t, tree f, tree r)
7580 gcc_assert (CONTAINS_PLACEHOLDER_P (r));
7582 switch (TREE_CODE (t))
7587 if (CONTAINS_PLACEHOLDER_P (TYPE_MIN_VALUE (t))
7588 || CONTAINS_PLACEHOLDER_P (TYPE_MAX_VALUE (t)))
7590 tree low = SUBSTITUTE_IN_EXPR (TYPE_MIN_VALUE (t), f, r);
7591 tree high = SUBSTITUTE_IN_EXPR (TYPE_MAX_VALUE (t), f, r);
7593 if (low == TYPE_MIN_VALUE (t) && high == TYPE_MAX_VALUE (t))
7596 new = build_range_type (TREE_TYPE (t), low, high);
7597 if (TYPE_INDEX_TYPE (t))
7599 (new, substitute_in_type (TYPE_INDEX_TYPE (t), f, r));
7606 if (CONTAINS_PLACEHOLDER_P (TYPE_MIN_VALUE (t))
7607 || CONTAINS_PLACEHOLDER_P (TYPE_MAX_VALUE (t)))
7609 tree low = SUBSTITUTE_IN_EXPR (TYPE_MIN_VALUE (t), f, r);
7610 tree high = SUBSTITUTE_IN_EXPR (TYPE_MAX_VALUE (t), f, r);
7612 if (low == TYPE_MIN_VALUE (t) && high == TYPE_MAX_VALUE (t))
7615 new = copy_type (t);
7616 TYPE_MIN_VALUE (new) = low;
7617 TYPE_MAX_VALUE (new) = high;
7624 new = substitute_in_type (TREE_TYPE (t), f, r);
7625 if (new == TREE_TYPE (t))
7628 return build_complex_type (new);
7634 /* These should never show up here. */
7639 tree component = substitute_in_type (TREE_TYPE (t), f, r);
7640 tree domain = substitute_in_type (TYPE_DOMAIN (t), f, r);
7642 if (component == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7645 new = build_array_type (component, domain);
7646 TYPE_ALIGN (new) = TYPE_ALIGN (t);
7647 TYPE_USER_ALIGN (new) = TYPE_USER_ALIGN (t);
7648 SET_TYPE_MODE (new, TYPE_MODE (t));
7649 TYPE_SIZE (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r);
7650 TYPE_SIZE_UNIT (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r);
7651 TYPE_NONALIASED_COMPONENT (new) = TYPE_NONALIASED_COMPONENT (t);
7652 TYPE_MULTI_ARRAY_P (new) = TYPE_MULTI_ARRAY_P (t);
7653 TYPE_CONVENTION_FORTRAN_P (new) = TYPE_CONVENTION_FORTRAN_P (t);
7659 case QUAL_UNION_TYPE:
7661 bool changed_field = false;
7664 /* Start out with no fields, make new fields, and chain them
7665 in. If we haven't actually changed the type of any field,
7666 discard everything we've done and return the old type. */
7667 new = copy_type (t);
7668 TYPE_FIELDS (new) = NULL_TREE;
7670 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
7672 tree new_field = copy_node (field), new_n;
7674 new_n = substitute_in_type (TREE_TYPE (field), f, r);
7675 if (new_n != TREE_TYPE (field))
7677 TREE_TYPE (new_field) = new_n;
7678 changed_field = true;
7681 new_n = SUBSTITUTE_IN_EXPR (DECL_FIELD_OFFSET (field), f, r);
7682 if (new_n != DECL_FIELD_OFFSET (field))
7684 DECL_FIELD_OFFSET (new_field) = new_n;
7685 changed_field = true;
7688 /* Do the substitution inside the qualifier, if any. */
7689 if (TREE_CODE (t) == QUAL_UNION_TYPE)
7691 new_n = SUBSTITUTE_IN_EXPR (DECL_QUALIFIER (field), f, r);
7692 if (new_n != DECL_QUALIFIER (field))
7694 DECL_QUALIFIER (new_field) = new_n;
7695 changed_field = true;
7699 DECL_CONTEXT (new_field) = new;
7700 SET_DECL_ORIGINAL_FIELD (new_field,
7701 (DECL_ORIGINAL_FIELD (field)
7702 ? DECL_ORIGINAL_FIELD (field) : field));
7704 TREE_CHAIN (new_field) = TYPE_FIELDS (new);
7705 TYPE_FIELDS (new) = new_field;
7711 TYPE_FIELDS (new) = nreverse (TYPE_FIELDS (new));
7712 TYPE_SIZE (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r);
7713 TYPE_SIZE_UNIT (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r);
7714 SET_TYPE_ADA_SIZE (new, SUBSTITUTE_IN_EXPR (TYPE_ADA_SIZE (t), f, r));
7723 /* Return the "RM size" of GNU_TYPE. This is the actual number of bits
7724 needed to represent the object. */
7727 rm_size (tree gnu_type)
7729 /* For integer types, this is the precision. For record types, we store
7730 the size explicitly. For other types, this is just the size. */
7732 if (INTEGRAL_TYPE_P (gnu_type) && TYPE_RM_SIZE (gnu_type))
7733 return TYPE_RM_SIZE (gnu_type);
7734 else if (TREE_CODE (gnu_type) == RECORD_TYPE
7735 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
7736 /* Return the rm_size of the actual data plus the size of the template. */
7738 size_binop (PLUS_EXPR,
7739 rm_size (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type)))),
7740 DECL_SIZE (TYPE_FIELDS (gnu_type)));
7741 else if ((TREE_CODE (gnu_type) == RECORD_TYPE
7742 || TREE_CODE (gnu_type) == UNION_TYPE
7743 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
7744 && !TYPE_IS_FAT_POINTER_P (gnu_type)
7745 && TYPE_ADA_SIZE (gnu_type))
7746 return TYPE_ADA_SIZE (gnu_type);
7748 return TYPE_SIZE (gnu_type);
7751 /* Return an identifier representing the external name to be used for
7752 GNAT_ENTITY. If SUFFIX is specified, the name is followed by "___"
7753 and the specified suffix. */
7756 create_concat_name (Entity_Id gnat_entity, const char *suffix)
7758 Entity_Kind kind = Ekind (gnat_entity);
7760 const char *str = (!suffix ? "" : suffix);
7761 String_Template temp = {1, strlen (str)};
7762 Fat_Pointer fp = {str, &temp};
7764 Get_External_Name_With_Suffix (gnat_entity, fp);
7766 /* A variable using the Stdcall convention (meaning we are running
7767 on a Windows box) live in a DLL. Here we adjust its name to use
7768 the jump-table, the _imp__NAME contains the address for the NAME
7770 if ((kind == E_Variable || kind == E_Constant)
7771 && Has_Stdcall_Convention (gnat_entity))
7773 const char *prefix = "_imp__";
7774 int k, plen = strlen (prefix);
7776 for (k = 0; k <= Name_Len; k++)
7777 Name_Buffer [Name_Len - k + plen] = Name_Buffer [Name_Len - k];
7778 strncpy (Name_Buffer, prefix, plen);
7781 return get_identifier (Name_Buffer);
7784 /* Return the name to be used for GNAT_ENTITY. If a type, create a
7785 fully-qualified name, possibly with type information encoding.
7786 Otherwise, return the name. */
7789 get_entity_name (Entity_Id gnat_entity)
7791 Get_Encoded_Name (gnat_entity);
7792 return get_identifier (Name_Buffer);
7795 /* Given GNU_ID, an IDENTIFIER_NODE containing a name and SUFFIX, a
7796 string, return a new IDENTIFIER_NODE that is the concatenation of
7797 the name in GNU_ID and SUFFIX. */
7800 concat_id_with_name (tree gnu_id, const char *suffix)
7802 int len = IDENTIFIER_LENGTH (gnu_id);
7804 strncpy (Name_Buffer, IDENTIFIER_POINTER (gnu_id), len);
7805 strncpy (Name_Buffer + len, "___", 3);
7807 strcpy (Name_Buffer + len, suffix);
7808 return get_identifier (Name_Buffer);
7811 #include "gt-ada-decl.h"