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"
53 #ifndef MAX_FIXED_MODE_SIZE
54 #define MAX_FIXED_MODE_SIZE GET_MODE_BITSIZE (DImode)
57 /* Convention_Stdcall should be processed in a specific way on Windows targets
58 only. The macro below is a helper to avoid having to check for a Windows
59 specific attribute throughout this unit. */
61 #if TARGET_DLLIMPORT_DECL_ATTRIBUTES
62 #define Has_Stdcall_Convention(E) (Convention (E) == Convention_Stdcall)
64 #define Has_Stdcall_Convention(E) (0)
67 /* Stack realignment for functions with foreign conventions is provided on a
68 per back-end basis now, as it is handled by the prologue expanders and not
69 as part of the function's body any more. It might be requested by way of a
70 dedicated function type attribute on the targets that support it.
72 We need a way to avoid setting the attribute on the targets that don't
73 support it and use FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN for this purpose.
75 It is defined on targets where the circuitry is available, and indicates
76 whether the realignment is needed for 'main'. We use this to decide for
77 foreign subprograms as well.
79 It is not defined on targets where the circuitry is not implemented, and
80 we just never set the attribute in these cases.
82 Whether it is defined on all targets that would need it in theory is
83 not entirely clear. We currently trust the base GCC settings for this
86 #ifndef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
87 #define FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN 0
92 struct incomplete *next;
97 /* These variables are used to defer recursively expanding incomplete types
98 while we are processing an array, a record or a subprogram type. */
99 static int defer_incomplete_level = 0;
100 static struct incomplete *defer_incomplete_list;
102 /* This variable is used to delay expanding From_With_Type types until the
104 static struct incomplete *defer_limited_with;
106 /* These variables are used to defer finalizing types. The element of the
107 list is the TYPE_DECL associated with the type. */
108 static int defer_finalize_level = 0;
109 static VEC (tree,heap) *defer_finalize_list;
111 /* A hash table used to cache the result of annotate_value. */
112 static GTY ((if_marked ("tree_int_map_marked_p"),
113 param_is (struct tree_int_map))) htab_t annotate_value_cache;
122 static void relate_alias_sets (tree, tree, enum alias_set_op);
124 static tree substitution_list (Entity_Id, Entity_Id, tree, bool);
125 static bool allocatable_size_p (tree, bool);
126 static void prepend_one_attribute_to (struct attrib **,
127 enum attr_type, tree, tree, Node_Id);
128 static void prepend_attributes (Entity_Id, struct attrib **);
129 static tree elaborate_expression (Node_Id, Entity_Id, tree, bool, bool, bool);
130 static bool is_variable_size (tree);
131 static tree elaborate_expression_1 (tree, Entity_Id, tree, bool, bool);
132 static tree make_packable_type (tree, bool);
133 static tree gnat_to_gnu_field (Entity_Id, tree, int, bool);
134 static tree gnat_to_gnu_param (Entity_Id, Mechanism_Type, Entity_Id, bool,
136 static bool same_discriminant_p (Entity_Id, Entity_Id);
137 static bool array_type_has_nonaliased_component (Entity_Id, tree);
138 static bool compile_time_known_address_p (Node_Id);
139 static void components_to_record (tree, Node_Id, tree, int, bool, tree *,
140 bool, bool, bool, bool);
141 static Uint annotate_value (tree);
142 static void annotate_rep (Entity_Id, tree);
143 static tree compute_field_positions (tree, tree, tree, tree, unsigned int);
144 static tree validate_size (Uint, tree, Entity_Id, enum tree_code, bool, bool);
145 static void set_rm_size (Uint, tree, Entity_Id);
146 static tree make_type_from_size (tree, tree, bool);
147 static unsigned int validate_alignment (Uint, Entity_Id, unsigned int);
148 static unsigned int ceil_alignment (unsigned HOST_WIDE_INT);
149 static void check_ok_for_atomic (tree, Entity_Id, bool);
150 static int compatible_signatures_p (tree ftype1, tree ftype2);
151 static void rest_of_type_decl_compilation_no_defer (tree);
153 /* Given GNAT_ENTITY, a GNAT defining identifier node, which denotes some Ada
154 entity, return the equivalent GCC tree for that entity (a ..._DECL node)
155 and associate the ..._DECL node with the input GNAT defining identifier.
157 If GNAT_ENTITY is a variable or a constant declaration, GNU_EXPR gives its
158 initial value (in GCC tree form). This is optional for a variable. For
159 a renamed entity, GNU_EXPR gives the object being renamed.
161 DEFINITION is nonzero if this call is intended for a definition. This is
162 used for separate compilation where it is necessary to know whether an
163 external declaration or a definition must be created if the GCC equivalent
164 was not created previously. The value of 1 is normally used for a nonzero
165 DEFINITION, but a value of 2 is used in special circumstances, defined in
169 gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition)
171 /* Contains the kind of the input GNAT node. */
172 const Entity_Kind kind = Ekind (gnat_entity);
173 /* True if this is a type. */
174 const bool is_type = IN (kind, Type_Kind);
175 /* For a type, contains the equivalent GNAT node to be used in gigi. */
176 Entity_Id gnat_equiv_type = Empty;
177 /* Temporary used to walk the GNAT tree. */
179 /* Contains the GCC DECL node which is equivalent to the input GNAT node.
180 This node will be associated with the GNAT node by calling at the end
181 of the `switch' statement. */
182 tree gnu_decl = NULL_TREE;
183 /* Contains the GCC type to be used for the GCC node. */
184 tree gnu_type = NULL_TREE;
185 /* Contains the GCC size tree to be used for the GCC node. */
186 tree gnu_size = NULL_TREE;
187 /* Contains the GCC name to be used for the GCC node. */
188 tree gnu_entity_name;
189 /* True if we have already saved gnu_decl as a GNAT association. */
191 /* True if we incremented defer_incomplete_level. */
192 bool this_deferred = false;
193 /* True if we incremented force_global. */
194 bool this_global = false;
195 /* True if we should check to see if elaborated during processing. */
196 bool maybe_present = false;
197 /* True if we made GNU_DECL and its type here. */
198 bool this_made_decl = false;
199 /* True if debug info is requested for this entity. */
200 bool debug_info_p = (Needs_Debug_Info (gnat_entity)
201 || debug_info_level == DINFO_LEVEL_VERBOSE);
202 /* True if this entity is to be considered as imported. */
203 bool imported_p = (Is_Imported (gnat_entity)
204 && No (Address_Clause (gnat_entity)));
205 /* Size and alignment of the GCC node, if meaningful. */
206 unsigned int esize = 0, align = 0;
207 /* Contains the list of attributes directly attached to the entity. */
208 struct attrib *attr_list = NULL;
210 /* Since a use of an Itype is a definition, process it as such if it
211 is not in a with'ed unit. */
214 && Is_Itype (gnat_entity)
215 && !present_gnu_tree (gnat_entity)
216 && In_Extended_Main_Code_Unit (gnat_entity))
218 /* Ensure that we are in a subprogram mentioned in the Scope chain of
219 this entity, our current scope is global, or we encountered a task
220 or entry (where we can't currently accurately check scoping). */
221 if (!current_function_decl
222 || DECL_ELABORATION_PROC_P (current_function_decl))
224 process_type (gnat_entity);
225 return get_gnu_tree (gnat_entity);
228 for (gnat_temp = Scope (gnat_entity);
230 gnat_temp = Scope (gnat_temp))
232 if (Is_Type (gnat_temp))
233 gnat_temp = Underlying_Type (gnat_temp);
235 if (Ekind (gnat_temp) == E_Subprogram_Body)
237 = Corresponding_Spec (Parent (Declaration_Node (gnat_temp)));
239 if (IN (Ekind (gnat_temp), Subprogram_Kind)
240 && Present (Protected_Body_Subprogram (gnat_temp)))
241 gnat_temp = Protected_Body_Subprogram (gnat_temp);
243 if (Ekind (gnat_temp) == E_Entry
244 || Ekind (gnat_temp) == E_Entry_Family
245 || Ekind (gnat_temp) == E_Task_Type
246 || (IN (Ekind (gnat_temp), Subprogram_Kind)
247 && present_gnu_tree (gnat_temp)
248 && (current_function_decl
249 == gnat_to_gnu_entity (gnat_temp, NULL_TREE, 0))))
251 process_type (gnat_entity);
252 return get_gnu_tree (gnat_entity);
256 /* This abort means the Itype has an incorrect scope, i.e. that its
257 scope does not correspond to the subprogram it is declared in. */
261 /* If we've already processed this entity, return what we got last time.
262 If we are defining the node, we should not have already processed it.
263 In that case, we will abort below when we try to save a new GCC tree
264 for this object. We also need to handle the case of getting a dummy
265 type when a Full_View exists. */
266 if ((!definition || (is_type && imported_p))
267 && present_gnu_tree (gnat_entity))
269 gnu_decl = get_gnu_tree (gnat_entity);
271 if (TREE_CODE (gnu_decl) == TYPE_DECL
272 && TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl))
273 && IN (kind, Incomplete_Or_Private_Kind)
274 && Present (Full_View (gnat_entity)))
277 = gnat_to_gnu_entity (Full_View (gnat_entity), NULL_TREE, 0);
278 save_gnu_tree (gnat_entity, NULL_TREE, false);
279 save_gnu_tree (gnat_entity, gnu_decl, false);
285 /* If this is a numeric or enumeral type, or an access type, a nonzero
286 Esize must be specified unless it was specified by the programmer. */
287 gcc_assert (!Unknown_Esize (gnat_entity)
288 || Has_Size_Clause (gnat_entity)
289 || (!IN (kind, Numeric_Kind)
290 && !IN (kind, Enumeration_Kind)
291 && (!IN (kind, Access_Kind)
292 || kind == E_Access_Protected_Subprogram_Type
293 || kind == E_Anonymous_Access_Protected_Subprogram_Type
294 || kind == E_Access_Subtype)));
296 /* The RM size must be specified for all discrete and fixed-point types. */
297 gcc_assert (!(IN (kind, Discrete_Or_Fixed_Point_Kind)
298 && Unknown_RM_Size (gnat_entity)));
300 /* If we get here, it means we have not yet done anything with this entity.
301 If we are not defining it, it must be a type or an entity that is defined
302 elsewhere or externally, otherwise we should have defined it already. */
303 gcc_assert (definition
304 || type_annotate_only
306 || kind == E_Discriminant
307 || kind == E_Component
309 || (kind == E_Constant && Present (Full_View (gnat_entity)))
310 || Is_Public (gnat_entity));
312 /* Get the name of the entity and set up the line number and filename of
313 the original definition for use in any decl we make. */
314 gnu_entity_name = get_entity_name (gnat_entity);
315 Sloc_to_locus (Sloc (gnat_entity), &input_location);
317 /* For cases when we are not defining (i.e., we are referencing from
318 another compilation unit) public entities, show we are at global level
319 for the purpose of computing scopes. Don't do this for components or
320 discriminants since the relevant test is whether or not the record is
323 && kind != E_Component
324 && kind != E_Discriminant
325 && Is_Public (gnat_entity)
326 && !Is_Statically_Allocated (gnat_entity))
327 force_global++, this_global = true;
329 /* Handle any attributes directly attached to the entity. */
330 if (Has_Gigi_Rep_Item (gnat_entity))
331 prepend_attributes (gnat_entity, &attr_list);
333 /* Do some common processing for types. */
336 /* Compute the equivalent type to be used in gigi. */
337 gnat_equiv_type = Gigi_Equivalent_Type (gnat_entity);
339 /* Machine_Attributes on types are expected to be propagated to
340 subtypes. The corresponding Gigi_Rep_Items are only attached
341 to the first subtype though, so we handle the propagation here. */
342 if (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)),
348 /* Compute a default value for the size of the type. */
349 if (Known_Esize (gnat_entity)
350 && UI_Is_In_Int_Range (Esize (gnat_entity)))
352 unsigned int max_esize;
353 esize = UI_To_Int (Esize (gnat_entity));
355 if (IN (kind, Float_Kind))
356 max_esize = fp_prec_to_size (LONG_DOUBLE_TYPE_SIZE);
357 else if (IN (kind, Access_Kind))
358 max_esize = POINTER_SIZE * 2;
360 max_esize = LONG_LONG_TYPE_SIZE;
362 if (esize > max_esize)
366 esize = LONG_LONG_TYPE_SIZE;
372 /* If this is a use of a deferred constant without address clause,
373 get its full definition. */
375 && No (Address_Clause (gnat_entity))
376 && Present (Full_View (gnat_entity)))
379 = gnat_to_gnu_entity (Full_View (gnat_entity), gnu_expr, 0);
384 /* If we have an external constant that we are not defining, get the
385 expression that is was defined to represent. We may throw that
386 expression away later if it is not a constant. Do not retrieve the
387 expression if it is an aggregate or allocator, because in complex
388 instantiation contexts it may not be expanded */
390 && Present (Expression (Declaration_Node (gnat_entity)))
391 && !No_Initialization (Declaration_Node (gnat_entity))
392 && (Nkind (Expression (Declaration_Node (gnat_entity)))
394 && (Nkind (Expression (Declaration_Node (gnat_entity)))
396 gnu_expr = gnat_to_gnu (Expression (Declaration_Node (gnat_entity)));
398 /* Ignore deferred constant definitions without address clause since
399 they are processed fully in the front-end. If No_Initialization
400 is set, this is not a deferred constant but a constant whose value
401 is built manually. And constants that are renamings are handled
405 && No (Address_Clause (gnat_entity))
406 && !No_Initialization (Declaration_Node (gnat_entity))
407 && No (Renamed_Object (gnat_entity)))
409 gnu_decl = error_mark_node;
414 /* Ignore constant definitions already marked with the error node. See
415 the N_Object_Declaration case of gnat_to_gnu for the rationale. */
418 && present_gnu_tree (gnat_entity)
419 && get_gnu_tree (gnat_entity) == error_mark_node)
421 maybe_present = true;
428 /* We used to special case VMS exceptions here to directly map them to
429 their associated condition code. Since this code had to be masked
430 dynamically to strip off the severity bits, this caused trouble in
431 the GCC/ZCX case because the "type" pointers we store in the tables
432 have to be static. We now don't special case here anymore, and let
433 the regular processing take place, which leaves us with a regular
434 exception data object for VMS exceptions too. The condition code
435 mapping is taken care of by the front end and the bitmasking by the
442 /* The GNAT record where the component was defined. */
443 Entity_Id gnat_record = Underlying_Type (Scope (gnat_entity));
445 /* If the variable is an inherited record component (in the case of
446 extended record types), just return the inherited entity, which
447 must be a FIELD_DECL. Likewise for discriminants.
448 For discriminants of untagged records which have explicit
449 stored discriminants, return the entity for the corresponding
450 stored discriminant. Also use Original_Record_Component
451 if the record has a private extension. */
452 if (Present (Original_Record_Component (gnat_entity))
453 && Original_Record_Component (gnat_entity) != gnat_entity)
456 = gnat_to_gnu_entity (Original_Record_Component (gnat_entity),
457 gnu_expr, definition);
462 /* If the enclosing record has explicit stored discriminants,
463 then it is an untagged record. If the Corresponding_Discriminant
464 is not empty then this must be a renamed discriminant and its
465 Original_Record_Component must point to the corresponding explicit
466 stored discriminant (i.e. we should have taken the previous
468 else if (Present (Corresponding_Discriminant (gnat_entity))
469 && Is_Tagged_Type (gnat_record))
471 /* A tagged record has no explicit stored discriminants. */
472 gcc_assert (First_Discriminant (gnat_record)
473 == First_Stored_Discriminant (gnat_record));
475 = gnat_to_gnu_entity (Corresponding_Discriminant (gnat_entity),
476 gnu_expr, definition);
481 else if (Present (CR_Discriminant (gnat_entity))
482 && type_annotate_only)
484 gnu_decl = gnat_to_gnu_entity (CR_Discriminant (gnat_entity),
485 gnu_expr, definition);
490 /* If the enclosing record has explicit stored discriminants, then
491 it is an untagged record. If the Corresponding_Discriminant
492 is not empty then this must be a renamed discriminant and its
493 Original_Record_Component must point to the corresponding explicit
494 stored discriminant (i.e. we should have taken the first
496 else if (Present (Corresponding_Discriminant (gnat_entity))
497 && (First_Discriminant (gnat_record)
498 != First_Stored_Discriminant (gnat_record)))
501 /* Otherwise, if we are not defining this and we have no GCC type
502 for the containing record, make one for it. Then we should
503 have made our own equivalent. */
504 else if (!definition && !present_gnu_tree (gnat_record))
506 /* ??? If this is in a record whose scope is a protected
507 type and we have an Original_Record_Component, use it.
508 This is a workaround for major problems in protected type
510 Entity_Id Scop = Scope (Scope (gnat_entity));
511 if ((Is_Protected_Type (Scop)
512 || (Is_Private_Type (Scop)
513 && Present (Full_View (Scop))
514 && Is_Protected_Type (Full_View (Scop))))
515 && Present (Original_Record_Component (gnat_entity)))
518 = gnat_to_gnu_entity (Original_Record_Component
525 gnat_to_gnu_entity (Scope (gnat_entity), NULL_TREE, 0);
526 gnu_decl = get_gnu_tree (gnat_entity);
532 /* Here we have no GCC type and this is a reference rather than a
533 definition. This should never happen. Most likely the cause is
534 reference before declaration in the gnat tree for gnat_entity. */
538 case E_Loop_Parameter:
539 case E_Out_Parameter:
542 /* Simple variables, loop variables, Out parameters, and exceptions. */
545 bool used_by_ref = false;
547 = ((kind == E_Constant || kind == E_Variable)
548 && Is_True_Constant (gnat_entity)
549 && !Treat_As_Volatile (gnat_entity)
550 && (((Nkind (Declaration_Node (gnat_entity))
551 == N_Object_Declaration)
552 && Present (Expression (Declaration_Node (gnat_entity))))
553 || Present (Renamed_Object (gnat_entity))));
554 bool inner_const_flag = const_flag;
555 bool static_p = Is_Statically_Allocated (gnat_entity);
556 bool mutable_p = false;
557 tree gnu_ext_name = NULL_TREE;
558 tree renamed_obj = NULL_TREE;
559 tree gnu_object_size;
561 if (Present (Renamed_Object (gnat_entity)) && !definition)
563 if (kind == E_Exception)
564 gnu_expr = gnat_to_gnu_entity (Renamed_Entity (gnat_entity),
567 gnu_expr = gnat_to_gnu (Renamed_Object (gnat_entity));
570 /* Get the type after elaborating the renamed object. */
571 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
573 /* For a debug renaming declaration, build a pure debug entity. */
574 if (Present (Debug_Renaming_Link (gnat_entity)))
577 gnu_decl = build_decl (VAR_DECL, gnu_entity_name, gnu_type);
578 /* The (MEM (CONST (0))) pattern is prescribed by STABS. */
579 if (global_bindings_p ())
580 addr = gen_rtx_CONST (VOIDmode, const0_rtx);
582 addr = stack_pointer_rtx;
583 SET_DECL_RTL (gnu_decl, gen_rtx_MEM (Pmode, addr));
584 gnat_pushdecl (gnu_decl, gnat_entity);
588 /* If this is a loop variable, its type should be the base type.
589 This is because the code for processing a loop determines whether
590 a normal loop end test can be done by comparing the bounds of the
591 loop against those of the base type, which is presumed to be the
592 size used for computation. But this is not correct when the size
593 of the subtype is smaller than the type. */
594 if (kind == E_Loop_Parameter)
595 gnu_type = get_base_type (gnu_type);
597 /* Reject non-renamed objects whose types are unconstrained arrays or
598 any object whose type is a dummy type or VOID_TYPE. */
600 if ((TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE
601 && No (Renamed_Object (gnat_entity)))
602 || TYPE_IS_DUMMY_P (gnu_type)
603 || TREE_CODE (gnu_type) == VOID_TYPE)
605 gcc_assert (type_annotate_only);
608 return error_mark_node;
611 /* If an alignment is specified, use it if valid. Note that
612 exceptions are objects but don't have alignments. We must do this
613 before we validate the size, since the alignment can affect the
615 if (kind != E_Exception && Known_Alignment (gnat_entity))
617 gcc_assert (Present (Alignment (gnat_entity)));
618 align = validate_alignment (Alignment (gnat_entity), gnat_entity,
619 TYPE_ALIGN (gnu_type));
620 gnu_type = maybe_pad_type (gnu_type, NULL_TREE, align, gnat_entity,
621 "PAD", false, definition, true);
624 /* If we are defining the object, see if it has a Size value and
625 validate it if so. If we are not defining the object and a Size
626 clause applies, simply retrieve the value. We don't want to ignore
627 the clause and it is expected to have been validated already. Then
628 get the new type, if any. */
630 gnu_size = validate_size (Esize (gnat_entity), gnu_type,
631 gnat_entity, VAR_DECL, false,
632 Has_Size_Clause (gnat_entity));
633 else if (Has_Size_Clause (gnat_entity))
634 gnu_size = UI_To_gnu (Esize (gnat_entity), bitsizetype);
639 = make_type_from_size (gnu_type, gnu_size,
640 Has_Biased_Representation (gnat_entity));
642 if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0))
643 gnu_size = NULL_TREE;
646 /* If this object has self-referential size, it must be a record with
647 a default value. We are supposed to allocate an object of the
648 maximum size in this case unless it is a constant with an
649 initializing expression, in which case we can get the size from
650 that. Note that the resulting size may still be a variable, so
651 this may end up with an indirect allocation. */
652 if (No (Renamed_Object (gnat_entity))
653 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
655 if (gnu_expr && kind == E_Constant)
657 tree size = TYPE_SIZE (TREE_TYPE (gnu_expr));
658 if (CONTAINS_PLACEHOLDER_P (size))
660 /* If the initializing expression is itself a constant,
661 despite having a nominal type with self-referential
662 size, we can get the size directly from it. */
663 if (TREE_CODE (gnu_expr) == COMPONENT_REF
664 && TREE_CODE (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
667 (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
668 && TREE_CODE (TREE_OPERAND (gnu_expr, 0)) == VAR_DECL
669 && (TREE_READONLY (TREE_OPERAND (gnu_expr, 0))
670 || DECL_READONLY_ONCE_ELAB
671 (TREE_OPERAND (gnu_expr, 0))))
672 gnu_size = DECL_SIZE (TREE_OPERAND (gnu_expr, 0));
675 = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, gnu_expr);
680 /* We may have no GNU_EXPR because No_Initialization is
681 set even though there's an Expression. */
682 else if (kind == E_Constant
683 && (Nkind (Declaration_Node (gnat_entity))
684 == N_Object_Declaration)
685 && Present (Expression (Declaration_Node (gnat_entity))))
687 = TYPE_SIZE (gnat_to_gnu_type
689 (Expression (Declaration_Node (gnat_entity)))));
692 gnu_size = max_size (TYPE_SIZE (gnu_type), true);
697 /* If the size is zero bytes, make it one byte since some linkers have
698 trouble with zero-sized objects. If the object will have a
699 template, that will make it nonzero so don't bother. Also avoid
700 doing that for an object renaming or an object with an address
701 clause, as we would lose useful information on the view size
702 (e.g. for null array slices) and we are not allocating the object
705 && integer_zerop (gnu_size)
706 && !TREE_OVERFLOW (gnu_size))
707 || (TYPE_SIZE (gnu_type)
708 && integer_zerop (TYPE_SIZE (gnu_type))
709 && !TREE_OVERFLOW (TYPE_SIZE (gnu_type))))
710 && (!Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
711 || !Is_Array_Type (Etype (gnat_entity)))
712 && No (Renamed_Object (gnat_entity))
713 && No (Address_Clause (gnat_entity)))
714 gnu_size = bitsize_unit_node;
716 /* If this is an object with no specified size and alignment, and
717 if either it is atomic or we are not optimizing alignment for
718 space and it is composite and not an exception, an Out parameter
719 or a reference to another object, and the size of its type is a
720 constant, set the alignment to the smallest one which is not
721 smaller than the size, with an appropriate cap. */
722 if (!gnu_size && align == 0
723 && (Is_Atomic (gnat_entity)
724 || (!Optimize_Alignment_Space (gnat_entity)
725 && kind != E_Exception
726 && kind != E_Out_Parameter
727 && Is_Composite_Type (Etype (gnat_entity))
728 && !Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
730 && No (Renamed_Object (gnat_entity))
731 && No (Address_Clause (gnat_entity))))
732 && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST)
734 /* No point in jumping through all the hoops needed in order
735 to support BIGGEST_ALIGNMENT if we don't really have to.
736 So we cap to the smallest alignment that corresponds to
737 a known efficient memory access pattern of the target. */
738 unsigned int align_cap = Is_Atomic (gnat_entity)
740 : get_mode_alignment (ptr_mode);
742 if (!host_integerp (TYPE_SIZE (gnu_type), 1)
743 || compare_tree_int (TYPE_SIZE (gnu_type), align_cap) >= 0)
746 align = ceil_alignment (tree_low_cst (TYPE_SIZE (gnu_type), 1));
748 /* But make sure not to under-align the object. */
749 if (align <= TYPE_ALIGN (gnu_type))
752 /* And honor the minimum valid atomic alignment, if any. */
753 #ifdef MINIMUM_ATOMIC_ALIGNMENT
754 else if (align < MINIMUM_ATOMIC_ALIGNMENT)
755 align = MINIMUM_ATOMIC_ALIGNMENT;
759 /* If the object is set to have atomic components, find the component
760 type and validate it.
762 ??? Note that we ignore Has_Volatile_Components on objects; it's
763 not at all clear what to do in that case. */
765 if (Has_Atomic_Components (gnat_entity))
767 tree gnu_inner = (TREE_CODE (gnu_type) == ARRAY_TYPE
768 ? TREE_TYPE (gnu_type) : gnu_type);
770 while (TREE_CODE (gnu_inner) == ARRAY_TYPE
771 && TYPE_MULTI_ARRAY_P (gnu_inner))
772 gnu_inner = TREE_TYPE (gnu_inner);
774 check_ok_for_atomic (gnu_inner, gnat_entity, true);
777 /* Now check if the type of the object allows atomic access. Note
778 that we must test the type, even if this object has size and
779 alignment to allow such access, because we will be going
780 inside the padded record to assign to the object. We could fix
781 this by always copying via an intermediate value, but it's not
782 clear it's worth the effort. */
783 if (Is_Atomic (gnat_entity))
784 check_ok_for_atomic (gnu_type, gnat_entity, false);
786 /* If this is an aliased object with an unconstrained nominal subtype,
787 make a type that includes the template. */
788 if (Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity))
789 && Is_Array_Type (Etype (gnat_entity))
790 && !type_annotate_only)
793 = TREE_TYPE (gnat_to_gnu_type (Base_Type (Etype (gnat_entity))));
796 = build_unc_object_type_from_ptr (gnu_fat, gnu_type,
797 concat_name (gnu_entity_name,
801 #ifdef MINIMUM_ATOMIC_ALIGNMENT
802 /* If the size is a constant and no alignment is specified, force
803 the alignment to be the minimum valid atomic alignment. The
804 restriction on constant size avoids problems with variable-size
805 temporaries; if the size is variable, there's no issue with
806 atomic access. Also don't do this for a constant, since it isn't
807 necessary and can interfere with constant replacement. Finally,
808 do not do it for Out parameters since that creates an
809 size inconsistency with In parameters. */
810 if (align == 0 && MINIMUM_ATOMIC_ALIGNMENT > TYPE_ALIGN (gnu_type)
811 && !FLOAT_TYPE_P (gnu_type)
812 && !const_flag && No (Renamed_Object (gnat_entity))
813 && !imported_p && No (Address_Clause (gnat_entity))
814 && kind != E_Out_Parameter
815 && (gnu_size ? TREE_CODE (gnu_size) == INTEGER_CST
816 : TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST))
817 align = MINIMUM_ATOMIC_ALIGNMENT;
820 /* Make a new type with the desired size and alignment, if needed.
821 But do not take into account alignment promotions to compute the
822 size of the object. */
823 gnu_object_size = gnu_size ? gnu_size : TYPE_SIZE (gnu_type);
824 if (gnu_size || align > 0)
825 gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity,
826 "PAD", false, definition,
827 gnu_size ? true : false);
829 /* If this is a renaming, avoid as much as possible to create a new
830 object. However, in several cases, creating it is required.
831 This processing needs to be applied to the raw expression so
832 as to make it more likely to rename the underlying object. */
833 if (Present (Renamed_Object (gnat_entity)))
835 bool create_normal_object = false;
837 /* If the renamed object had padding, strip off the reference
838 to the inner object and reset our type. */
839 if ((TREE_CODE (gnu_expr) == COMPONENT_REF
840 && TREE_CODE (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))
842 && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0))))
843 /* Strip useless conversions around the object. */
844 || (TREE_CODE (gnu_expr) == NOP_EXPR
845 && gnat_types_compatible_p
846 (TREE_TYPE (gnu_expr),
847 TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))))
849 gnu_expr = TREE_OPERAND (gnu_expr, 0);
850 gnu_type = TREE_TYPE (gnu_expr);
853 /* Case 1: If this is a constant renaming stemming from a function
854 call, treat it as a normal object whose initial value is what
855 is being renamed. RM 3.3 says that the result of evaluating a
856 function call is a constant object. As a consequence, it can
857 be the inner object of a constant renaming. In this case, the
858 renaming must be fully instantiated, i.e. it cannot be a mere
859 reference to (part of) an existing object. */
862 tree inner_object = gnu_expr;
863 while (handled_component_p (inner_object))
864 inner_object = TREE_OPERAND (inner_object, 0);
865 if (TREE_CODE (inner_object) == CALL_EXPR)
866 create_normal_object = true;
869 /* Otherwise, see if we can proceed with a stabilized version of
870 the renamed entity or if we need to make a new object. */
871 if (!create_normal_object)
873 tree maybe_stable_expr = NULL_TREE;
876 /* Case 2: If the renaming entity need not be materialized and
877 the renamed expression is something we can stabilize, use
878 that for the renaming. At the global level, we can only do
879 this if we know no SAVE_EXPRs need be made, because the
880 expression we return might be used in arbitrary conditional
881 branches so we must force the SAVE_EXPRs evaluation
882 immediately and this requires a function context. */
883 if (!Materialize_Entity (gnat_entity)
884 && (!global_bindings_p ()
885 || (staticp (gnu_expr)
886 && !TREE_SIDE_EFFECTS (gnu_expr))))
889 = maybe_stabilize_reference (gnu_expr, true, &stable);
893 gnu_decl = maybe_stable_expr;
894 /* ??? No DECL_EXPR is created so we need to mark
895 the expression manually lest it is shared. */
896 if (global_bindings_p ())
897 mark_visited (&gnu_decl);
898 save_gnu_tree (gnat_entity, gnu_decl, true);
903 /* The stabilization failed. Keep maybe_stable_expr
904 untouched here to let the pointer case below know
905 about that failure. */
908 /* Case 3: If this is a constant renaming and creating a
909 new object is allowed and cheap, treat it as a normal
910 object whose initial value is what is being renamed. */
912 && !Is_Composite_Type
913 (Underlying_Type (Etype (gnat_entity))))
916 /* Case 4: Make this into a constant pointer to the object we
917 are to rename and attach the object to the pointer if it is
918 something we can stabilize.
920 From the proper scope, attached objects will be referenced
921 directly instead of indirectly via the pointer to avoid
922 subtle aliasing problems with non-addressable entities.
923 They have to be stable because we must not evaluate the
924 variables in the expression every time the renaming is used.
925 The pointer is called a "renaming" pointer in this case.
927 In the rare cases where we cannot stabilize the renamed
928 object, we just make a "bare" pointer, and the renamed
929 entity is always accessed indirectly through it. */
932 gnu_type = build_reference_type (gnu_type);
933 inner_const_flag = TREE_READONLY (gnu_expr);
936 /* If the previous attempt at stabilizing failed, there
937 is no point in trying again and we reuse the result
938 without attaching it to the pointer. In this case it
939 will only be used as the initializing expression of
940 the pointer and thus needs no special treatment with
941 regard to multiple evaluations. */
942 if (maybe_stable_expr)
945 /* Otherwise, try to stabilize and attach the expression
946 to the pointer if the stabilization succeeds.
948 Note that this might introduce SAVE_EXPRs and we don't
949 check whether we're at the global level or not. This
950 is fine since we are building a pointer initializer and
951 neither the pointer nor the initializing expression can
952 be accessed before the pointer elaboration has taken
953 place in a correct program.
955 These SAVE_EXPRs will be evaluated at the right place
956 by either the evaluation of the initializer for the
957 non-global case or the elaboration code for the global
958 case, and will be attached to the elaboration procedure
959 in the latter case. */
963 = maybe_stabilize_reference (gnu_expr, true, &stable);
966 renamed_obj = maybe_stable_expr;
968 /* Attaching is actually performed downstream, as soon
969 as we have a VAR_DECL for the pointer we make. */
973 = build_unary_op (ADDR_EXPR, gnu_type, maybe_stable_expr);
975 gnu_size = NULL_TREE;
981 /* Make a volatile version of this object's type if we are to make
982 the object volatile. We also interpret 13.3(19) conservatively
983 and disallow any optimizations for such a non-constant object. */
984 if ((Treat_As_Volatile (gnat_entity)
986 && (Is_Exported (gnat_entity)
987 || Is_Imported (gnat_entity)
988 || Present (Address_Clause (gnat_entity)))))
989 && !TYPE_VOLATILE (gnu_type))
990 gnu_type = build_qualified_type (gnu_type,
991 (TYPE_QUALS (gnu_type)
992 | TYPE_QUAL_VOLATILE));
994 /* If we are defining an aliased object whose nominal subtype is
995 unconstrained, the object is a record that contains both the
996 template and the object. If there is an initializer, it will
997 have already been converted to the right type, but we need to
998 create the template if there is no initializer. */
1001 && TREE_CODE (gnu_type) == RECORD_TYPE
1002 && (TYPE_CONTAINS_TEMPLATE_P (gnu_type)
1003 /* Beware that padding might have been introduced
1004 via maybe_pad_type above. */
1005 || (TYPE_IS_PADDING_P (gnu_type)
1006 && TREE_CODE (TREE_TYPE (TYPE_FIELDS (gnu_type)))
1008 && TYPE_CONTAINS_TEMPLATE_P
1009 (TREE_TYPE (TYPE_FIELDS (gnu_type))))))
1012 = TYPE_IS_PADDING_P (gnu_type)
1013 ? TYPE_FIELDS (TREE_TYPE (TYPE_FIELDS (gnu_type)))
1014 : TYPE_FIELDS (gnu_type);
1017 = gnat_build_constructor
1021 build_template (TREE_TYPE (template_field),
1022 TREE_TYPE (TREE_CHAIN (template_field)),
1027 /* Convert the expression to the type of the object except in the
1028 case where the object's type is unconstrained or the object's type
1029 is a padded record whose field is of self-referential size. In
1030 the former case, converting will generate unnecessary evaluations
1031 of the CONSTRUCTOR to compute the size and in the latter case, we
1032 want to only copy the actual data. */
1034 && TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE
1035 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
1036 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1037 && TYPE_IS_PADDING_P (gnu_type)
1038 && (CONTAINS_PLACEHOLDER_P
1039 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (gnu_type)))))))
1040 gnu_expr = convert (gnu_type, gnu_expr);
1042 /* If this is a pointer and it does not have an initializing
1043 expression, initialize it to NULL, unless the object is
1046 && (POINTER_TYPE_P (gnu_type) || TYPE_FAT_POINTER_P (gnu_type))
1047 && !Is_Imported (gnat_entity) && !gnu_expr)
1048 gnu_expr = integer_zero_node;
1050 /* If we are defining the object and it has an Address clause, we must
1051 either get the address expression from the saved GCC tree for the
1052 object if it has a Freeze node, or elaborate the address expression
1053 here since the front-end has guaranteed that the elaboration has no
1054 effects in this case. */
1055 if (definition && Present (Address_Clause (gnat_entity)))
1058 = present_gnu_tree (gnat_entity)
1059 ? get_gnu_tree (gnat_entity)
1060 : gnat_to_gnu (Expression (Address_Clause (gnat_entity)));
1062 save_gnu_tree (gnat_entity, NULL_TREE, false);
1064 /* Ignore the size. It's either meaningless or was handled
1066 gnu_size = NULL_TREE;
1067 /* Convert the type of the object to a reference type that can
1068 alias everything as per 13.3(19). */
1070 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
1071 gnu_address = convert (gnu_type, gnu_address);
1073 const_flag = !Is_Public (gnat_entity)
1074 || compile_time_known_address_p (Expression (Address_Clause
1077 /* If this is a deferred constant, the initializer is attached to
1079 if (kind == E_Constant && Present (Full_View (gnat_entity)))
1082 (Expression (Declaration_Node (Full_View (gnat_entity))));
1084 /* If we don't have an initializing expression for the underlying
1085 variable, the initializing expression for the pointer is the
1086 specified address. Otherwise, we have to make a COMPOUND_EXPR
1087 to assign both the address and the initial value. */
1089 gnu_expr = gnu_address;
1092 = build2 (COMPOUND_EXPR, gnu_type,
1094 (MODIFY_EXPR, NULL_TREE,
1095 build_unary_op (INDIRECT_REF, NULL_TREE,
1101 /* If it has an address clause and we are not defining it, mark it
1102 as an indirect object. Likewise for Stdcall objects that are
1104 if ((!definition && Present (Address_Clause (gnat_entity)))
1105 || (Is_Imported (gnat_entity)
1106 && Has_Stdcall_Convention (gnat_entity)))
1108 /* Convert the type of the object to a reference type that can
1109 alias everything as per 13.3(19). */
1111 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
1112 gnu_size = NULL_TREE;
1114 /* No point in taking the address of an initializing expression
1115 that isn't going to be used. */
1116 gnu_expr = NULL_TREE;
1118 /* If it has an address clause whose value is known at compile
1119 time, make the object a CONST_DECL. This will avoid a
1120 useless dereference. */
1121 if (Present (Address_Clause (gnat_entity)))
1123 Node_Id gnat_address
1124 = Expression (Address_Clause (gnat_entity));
1126 if (compile_time_known_address_p (gnat_address))
1128 gnu_expr = gnat_to_gnu (gnat_address);
1136 /* If we are at top level and this object is of variable size,
1137 make the actual type a hidden pointer to the real type and
1138 make the initializer be a memory allocation and initialization.
1139 Likewise for objects we aren't defining (presumed to be
1140 external references from other packages), but there we do
1141 not set up an initialization.
1143 If the object's size overflows, make an allocator too, so that
1144 Storage_Error gets raised. Note that we will never free
1145 such memory, so we presume it never will get allocated. */
1147 if (!allocatable_size_p (TYPE_SIZE_UNIT (gnu_type),
1148 global_bindings_p () || !definition
1151 && ! allocatable_size_p (gnu_size,
1152 global_bindings_p () || !definition
1155 gnu_type = build_reference_type (gnu_type);
1156 gnu_size = NULL_TREE;
1160 /* In case this was a aliased object whose nominal subtype is
1161 unconstrained, the pointer above will be a thin pointer and
1162 build_allocator will automatically make the template.
1164 If we have a template initializer only (that we made above),
1165 pretend there is none and rely on what build_allocator creates
1166 again anyway. Otherwise (if we have a full initializer), get
1167 the data part and feed that to build_allocator.
1169 If we are elaborating a mutable object, tell build_allocator to
1170 ignore a possibly simpler size from the initializer, if any, as
1171 we must allocate the maximum possible size in this case. */
1175 tree gnu_alloc_type = TREE_TYPE (gnu_type);
1177 if (TREE_CODE (gnu_alloc_type) == RECORD_TYPE
1178 && TYPE_CONTAINS_TEMPLATE_P (gnu_alloc_type))
1181 = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_alloc_type)));
1183 if (TREE_CODE (gnu_expr) == CONSTRUCTOR
1184 && 1 == VEC_length (constructor_elt,
1185 CONSTRUCTOR_ELTS (gnu_expr)))
1189 = build_component_ref
1190 (gnu_expr, NULL_TREE,
1191 TREE_CHAIN (TYPE_FIELDS (TREE_TYPE (gnu_expr))),
1195 if (TREE_CODE (TYPE_SIZE_UNIT (gnu_alloc_type)) == INTEGER_CST
1196 && TREE_OVERFLOW (TYPE_SIZE_UNIT (gnu_alloc_type))
1197 && !Is_Imported (gnat_entity))
1198 post_error ("?Storage_Error will be raised at run-time!",
1202 = build_allocator (gnu_alloc_type, gnu_expr, gnu_type,
1203 Empty, Empty, gnat_entity, mutable_p);
1207 gnu_expr = NULL_TREE;
1212 /* If this object would go into the stack and has an alignment larger
1213 than the largest stack alignment the back-end can honor, resort to
1214 a variable of "aligning type". */
1215 if (!global_bindings_p () && !static_p && definition
1216 && !imported_p && TYPE_ALIGN (gnu_type) > BIGGEST_ALIGNMENT)
1218 /* Create the new variable. No need for extra room before the
1219 aligned field as this is in automatic storage. */
1221 = make_aligning_type (gnu_type, TYPE_ALIGN (gnu_type),
1222 TYPE_SIZE_UNIT (gnu_type),
1223 BIGGEST_ALIGNMENT, 0);
1225 = create_var_decl (create_concat_name (gnat_entity, "ALIGN"),
1226 NULL_TREE, gnu_new_type, NULL_TREE, false,
1227 false, false, false, NULL, gnat_entity);
1229 /* Initialize the aligned field if we have an initializer. */
1232 (build_binary_op (MODIFY_EXPR, NULL_TREE,
1234 (gnu_new_var, NULL_TREE,
1235 TYPE_FIELDS (gnu_new_type), false),
1239 /* And setup this entity as a reference to the aligned field. */
1240 gnu_type = build_reference_type (gnu_type);
1243 (ADDR_EXPR, gnu_type,
1244 build_component_ref (gnu_new_var, NULL_TREE,
1245 TYPE_FIELDS (gnu_new_type), false));
1247 gnu_size = NULL_TREE;
1253 gnu_type = build_qualified_type (gnu_type, (TYPE_QUALS (gnu_type)
1254 | TYPE_QUAL_CONST));
1256 /* Convert the expression to the type of the object except in the
1257 case where the object's type is unconstrained or the object's type
1258 is a padded record whose field is of self-referential size. In
1259 the former case, converting will generate unnecessary evaluations
1260 of the CONSTRUCTOR to compute the size and in the latter case, we
1261 want to only copy the actual data. */
1263 && TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE
1264 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
1265 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1266 && TYPE_IS_PADDING_P (gnu_type)
1267 && (CONTAINS_PLACEHOLDER_P
1268 (TYPE_SIZE (TREE_TYPE (TYPE_FIELDS (gnu_type)))))))
1269 gnu_expr = convert (gnu_type, gnu_expr);
1271 /* If this name is external or there was a name specified, use it,
1272 unless this is a VMS exception object since this would conflict
1273 with the symbol we need to export in addition. Don't use the
1274 Interface_Name if there is an address clause (see CD30005). */
1275 if (!Is_VMS_Exception (gnat_entity)
1276 && ((Present (Interface_Name (gnat_entity))
1277 && No (Address_Clause (gnat_entity)))
1278 || (Is_Public (gnat_entity)
1279 && (!Is_Imported (gnat_entity)
1280 || Is_Exported (gnat_entity)))))
1281 gnu_ext_name = create_concat_name (gnat_entity, NULL);
1283 /* If this is constant initialized to a static constant and the
1284 object has an aggregate type, force it to be statically
1285 allocated. This will avoid an initialization copy. */
1286 if (!static_p && const_flag
1287 && gnu_expr && TREE_CONSTANT (gnu_expr)
1288 && AGGREGATE_TYPE_P (gnu_type)
1289 && host_integerp (TYPE_SIZE_UNIT (gnu_type), 1)
1290 && !(TREE_CODE (gnu_type) == RECORD_TYPE
1291 && TYPE_IS_PADDING_P (gnu_type)
1292 && !host_integerp (TYPE_SIZE_UNIT
1293 (TREE_TYPE (TYPE_FIELDS (gnu_type))), 1)))
1296 gnu_decl = create_var_decl (gnu_entity_name, gnu_ext_name, gnu_type,
1297 gnu_expr, const_flag,
1298 Is_Public (gnat_entity),
1299 imported_p || !definition,
1300 static_p, attr_list, gnat_entity);
1301 DECL_BY_REF_P (gnu_decl) = used_by_ref;
1302 DECL_POINTS_TO_READONLY_P (gnu_decl) = used_by_ref && inner_const_flag;
1303 if (TREE_CODE (gnu_decl) == VAR_DECL && renamed_obj)
1305 SET_DECL_RENAMED_OBJECT (gnu_decl, renamed_obj);
1306 if (global_bindings_p ())
1308 DECL_RENAMING_GLOBAL_P (gnu_decl) = 1;
1309 record_global_renaming_pointer (gnu_decl);
1313 if (definition && DECL_SIZE_UNIT (gnu_decl)
1314 && get_block_jmpbuf_decl ()
1315 && (TREE_CODE (DECL_SIZE_UNIT (gnu_decl)) != INTEGER_CST
1316 || (flag_stack_check == GENERIC_STACK_CHECK
1317 && compare_tree_int (DECL_SIZE_UNIT (gnu_decl),
1318 STACK_CHECK_MAX_VAR_SIZE) > 0)))
1319 add_stmt_with_node (build_call_1_expr
1320 (update_setjmp_buf_decl,
1321 build_unary_op (ADDR_EXPR, NULL_TREE,
1322 get_block_jmpbuf_decl ())),
1325 /* If we are defining an Out parameter and we're not optimizing,
1326 create a fake PARM_DECL for debugging purposes and make it
1327 point to the VAR_DECL. Suppress debug info for the latter
1328 but make sure it will still live on the stack so it can be
1329 accessed from within the debugger through the PARM_DECL. */
1330 if (kind == E_Out_Parameter && definition && !optimize)
1332 tree param = create_param_decl (gnu_entity_name, gnu_type, false);
1333 gnat_pushdecl (param, gnat_entity);
1334 SET_DECL_VALUE_EXPR (param, gnu_decl);
1335 DECL_HAS_VALUE_EXPR_P (param) = 1;
1337 debug_info_p = false;
1339 DECL_IGNORED_P (param) = 1;
1340 TREE_ADDRESSABLE (gnu_decl) = 1;
1343 /* If this is a public constant or we're not optimizing and we're not
1344 making a VAR_DECL for it, make one just for export or debugger use.
1345 Likewise if the address is taken or if either the object or type is
1346 aliased. Make an external declaration for a reference, unless this
1347 is a Standard entity since there no real symbol at the object level
1349 if (TREE_CODE (gnu_decl) == CONST_DECL
1350 && (definition || Sloc (gnat_entity) > Standard_Location)
1351 && ((Is_Public (gnat_entity) && No (Address_Clause (gnat_entity)))
1353 || Address_Taken (gnat_entity)
1354 || Is_Aliased (gnat_entity)
1355 || Is_Aliased (Etype (gnat_entity))))
1358 = create_true_var_decl (gnu_entity_name, gnu_ext_name, gnu_type,
1359 gnu_expr, true, Is_Public (gnat_entity),
1360 !definition, static_p, NULL,
1363 SET_DECL_CONST_CORRESPONDING_VAR (gnu_decl, gnu_corr_var);
1365 /* As debugging information will be generated for the variable,
1366 do not generate information for the constant. */
1367 DECL_IGNORED_P (gnu_decl) = 1;
1370 /* If this is declared in a block that contains a block with an
1371 exception handler, we must force this variable in memory to
1372 suppress an invalid optimization. */
1373 if (Has_Nested_Block_With_Handler (Scope (gnat_entity))
1374 && Exception_Mechanism != Back_End_Exceptions)
1375 TREE_ADDRESSABLE (gnu_decl) = 1;
1377 gnu_type = TREE_TYPE (gnu_decl);
1379 /* Back-annotate Alignment and Esize of the object if not already
1380 known, except for when the object is actually a pointer to the
1381 real object, since alignment and size of a pointer don't have
1382 anything to do with those of the designated object. Note that
1383 we pick the values of the type, not those of the object, to
1384 shield ourselves from low-level platform-dependent adjustments
1385 like alignment promotion. This is both consistent with all the
1386 treatment above, where alignment and size are set on the type of
1387 the object and not on the object directly, and makes it possible
1388 to support confirming representation clauses in all cases. */
1390 if (!used_by_ref && Unknown_Alignment (gnat_entity))
1391 Set_Alignment (gnat_entity,
1392 UI_From_Int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT));
1394 if (!used_by_ref && Unknown_Esize (gnat_entity))
1396 if (TREE_CODE (gnu_type) == RECORD_TYPE
1397 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
1399 = TYPE_SIZE (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type))));
1401 Set_Esize (gnat_entity, annotate_value (gnu_object_size));
1407 /* Return a TYPE_DECL for "void" that we previously made. */
1408 gnu_decl = TYPE_NAME (void_type_node);
1411 case E_Enumeration_Type:
1412 /* A special case: for the types Character and Wide_Character in
1413 Standard, we do not list all the literals. So if the literals
1414 are not specified, make this an unsigned type. */
1415 if (No (First_Literal (gnat_entity)))
1417 gnu_type = make_unsigned_type (esize);
1418 TYPE_NAME (gnu_type) = gnu_entity_name;
1420 /* Set TYPE_STRING_FLAG for Character and Wide_Character types.
1421 This is needed by the DWARF-2 back-end to distinguish between
1422 unsigned integer types and character types. */
1423 TYPE_STRING_FLAG (gnu_type) = 1;
1427 /* Normal case of non-character type or non-Standard character type. */
1429 /* Here we have a list of enumeral constants in First_Literal.
1430 We make a CONST_DECL for each and build into GNU_LITERAL_LIST
1431 the list to be placed into TYPE_FIELDS. Each node in the list
1432 is a TREE_LIST whose TREE_VALUE is the literal name and whose
1433 TREE_PURPOSE is the value of the literal. */
1435 Entity_Id gnat_literal;
1436 tree gnu_literal_list = NULL_TREE;
1438 if (Is_Unsigned_Type (gnat_entity))
1439 gnu_type = make_unsigned_type (esize);
1441 gnu_type = make_signed_type (esize);
1443 TREE_SET_CODE (gnu_type, ENUMERAL_TYPE);
1445 for (gnat_literal = First_Literal (gnat_entity);
1446 Present (gnat_literal);
1447 gnat_literal = Next_Literal (gnat_literal))
1449 tree gnu_value = UI_To_gnu (Enumeration_Rep (gnat_literal),
1452 = create_var_decl (get_entity_name (gnat_literal), NULL_TREE,
1453 gnu_type, gnu_value, true, false, false,
1454 false, NULL, gnat_literal);
1456 save_gnu_tree (gnat_literal, gnu_literal, false);
1457 gnu_literal_list = tree_cons (DECL_NAME (gnu_literal),
1458 gnu_value, gnu_literal_list);
1461 TYPE_VALUES (gnu_type) = nreverse (gnu_literal_list);
1463 /* Note that the bounds are updated at the end of this function
1464 to avoid an infinite recursion since they refer to the type. */
1468 case E_Signed_Integer_Type:
1469 case E_Ordinary_Fixed_Point_Type:
1470 case E_Decimal_Fixed_Point_Type:
1471 /* For integer types, just make a signed type the appropriate number
1473 gnu_type = make_signed_type (esize);
1476 case E_Modular_Integer_Type:
1478 /* For modular types, make the unsigned type of the proper number
1479 of bits and then set up the modulus, if required. */
1480 tree gnu_modulus, gnu_high = NULL_TREE;
1482 /* Packed array types are supposed to be subtypes only. */
1483 gcc_assert (!Is_Packed_Array_Type (gnat_entity));
1485 gnu_type = make_unsigned_type (esize);
1487 /* Get the modulus in this type. If it overflows, assume it is because
1488 it is equal to 2**Esize. Note that there is no overflow checking
1489 done on unsigned type, so we detect the overflow by looking for
1490 a modulus of zero, which is otherwise invalid. */
1491 gnu_modulus = UI_To_gnu (Modulus (gnat_entity), gnu_type);
1493 if (!integer_zerop (gnu_modulus))
1495 TYPE_MODULAR_P (gnu_type) = 1;
1496 SET_TYPE_MODULUS (gnu_type, gnu_modulus);
1497 gnu_high = fold_build2 (MINUS_EXPR, gnu_type, gnu_modulus,
1498 convert (gnu_type, integer_one_node));
1501 /* If the upper bound is not maximal, make an extra subtype. */
1503 && !tree_int_cst_equal (gnu_high, TYPE_MAX_VALUE (gnu_type)))
1505 tree gnu_subtype = make_unsigned_type (esize);
1506 SET_TYPE_RM_MAX_VALUE (gnu_subtype, gnu_high);
1507 TREE_TYPE (gnu_subtype) = gnu_type;
1508 TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1;
1509 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "UMT");
1510 gnu_type = gnu_subtype;
1515 case E_Signed_Integer_Subtype:
1516 case E_Enumeration_Subtype:
1517 case E_Modular_Integer_Subtype:
1518 case E_Ordinary_Fixed_Point_Subtype:
1519 case E_Decimal_Fixed_Point_Subtype:
1521 /* For integral subtypes, we make a new INTEGER_TYPE. Note that we do
1522 not want to call create_range_type since we would like each subtype
1523 node to be distinct. ??? Historically this was in preparation for
1524 when memory aliasing is implemented, but that's obsolete now given
1525 the call to relate_alias_sets below.
1527 The TREE_TYPE field of the INTEGER_TYPE points to the base type;
1528 this fact is used by the arithmetic conversion functions.
1530 We elaborate the Ancestor_Subtype if it is not in the current unit
1531 and one of our bounds is non-static. We do this to ensure consistent
1532 naming in the case where several subtypes share the same bounds, by
1533 elaborating the first such subtype first, thus using its name. */
1536 && Present (Ancestor_Subtype (gnat_entity))
1537 && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity))
1538 && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity))
1539 || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity))))
1540 gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity), gnu_expr, 0);
1542 /* Set the precision to the Esize except for bit-packed arrays. */
1543 if (Is_Packed_Array_Type (gnat_entity)
1544 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
1545 esize = UI_To_Int (RM_Size (gnat_entity));
1547 /* This should be an unsigned type if the base type is unsigned or
1548 if the lower bound is constant and non-negative or if the type
1550 if (Is_Unsigned_Type (Etype (gnat_entity))
1551 || Is_Unsigned_Type (gnat_entity)
1552 || Has_Biased_Representation (gnat_entity))
1553 gnu_type = make_unsigned_type (esize);
1555 gnu_type = make_signed_type (esize);
1556 TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity));
1558 SET_TYPE_RM_MIN_VALUE
1560 convert (TREE_TYPE (gnu_type),
1561 elaborate_expression (Type_Low_Bound (gnat_entity),
1562 gnat_entity, get_identifier ("L"),
1564 Needs_Debug_Info (gnat_entity))));
1566 SET_TYPE_RM_MAX_VALUE
1568 convert (TREE_TYPE (gnu_type),
1569 elaborate_expression (Type_High_Bound (gnat_entity),
1570 gnat_entity, get_identifier ("U"),
1572 Needs_Debug_Info (gnat_entity))));
1574 /* One of the above calls might have caused us to be elaborated,
1575 so don't blow up if so. */
1576 if (present_gnu_tree (gnat_entity))
1578 maybe_present = true;
1582 TYPE_BIASED_REPRESENTATION_P (gnu_type)
1583 = Has_Biased_Representation (gnat_entity);
1585 /* Attach the TYPE_STUB_DECL in case we have a parallel type. */
1586 TYPE_STUB_DECL (gnu_type)
1587 = create_type_stub_decl (gnu_entity_name, gnu_type);
1589 /* Inherit our alias set from what we're a subtype of. Subtypes
1590 are not different types and a pointer can designate any instance
1591 within a subtype hierarchy. */
1592 relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY);
1594 /* For a packed array, make the original array type a parallel type. */
1596 && Is_Packed_Array_Type (gnat_entity)
1597 && present_gnu_tree (Original_Array_Type (gnat_entity)))
1598 add_parallel_type (TYPE_STUB_DECL (gnu_type),
1600 (Original_Array_Type (gnat_entity)));
1602 /* If the type we are dealing with represents a bit-packed array,
1603 we need to have the bits left justified on big-endian targets
1604 and right justified on little-endian targets. We also need to
1605 ensure that when the value is read (e.g. for comparison of two
1606 such values), we only get the good bits, since the unused bits
1607 are uninitialized. Both goals are accomplished by wrapping up
1608 the modular type in an enclosing record type. */
1609 if (Is_Packed_Array_Type (gnat_entity)
1610 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
1612 tree gnu_field_type, gnu_field;
1614 /* Set the RM size before wrapping up the type. */
1615 SET_TYPE_RM_SIZE (gnu_type,
1616 UI_To_gnu (RM_Size (gnat_entity), bitsizetype));
1617 TYPE_PACKED_ARRAY_TYPE_P (gnu_type) = 1;
1618 gnu_field_type = gnu_type;
1620 gnu_type = make_node (RECORD_TYPE);
1621 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "JM");
1623 /* Propagate the alignment of the modular type to the record.
1624 This means that bit-packed arrays have "ceil" alignment for
1625 their size, which may seem counter-intuitive but makes it
1626 possible to easily overlay them on modular types. */
1627 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (gnu_field_type);
1628 TYPE_PACKED (gnu_type) = 1;
1630 /* Create a stripped-down declaration of the original type, mainly
1632 create_type_decl (gnu_entity_name, gnu_field_type, NULL, true,
1633 debug_info_p, gnat_entity);
1635 /* Don't notify the field as "addressable", since we won't be taking
1636 it's address and it would prevent create_field_decl from making a
1638 gnu_field = create_field_decl (get_identifier ("OBJECT"),
1639 gnu_field_type, gnu_type, 1, 0, 0, 0);
1641 /* Do not finalize it until after the parallel type is added. */
1642 finish_record_type (gnu_type, gnu_field, 0, true);
1643 TYPE_JUSTIFIED_MODULAR_P (gnu_type) = 1;
1645 relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY);
1647 /* Make the original array type a parallel type. */
1649 && present_gnu_tree (Original_Array_Type (gnat_entity)))
1650 add_parallel_type (TYPE_STUB_DECL (gnu_type),
1652 (Original_Array_Type (gnat_entity)));
1654 rest_of_record_type_compilation (gnu_type);
1657 /* If the type we are dealing with has got a smaller alignment than the
1658 natural one, we need to wrap it up in a record type and under-align
1659 the latter. We reuse the padding machinery for this purpose. */
1660 else if (Present (Alignment_Clause (gnat_entity))
1661 && UI_Is_In_Int_Range (Alignment (gnat_entity))
1662 && (align = UI_To_Int (Alignment (gnat_entity)) * BITS_PER_UNIT)
1663 && align < TYPE_ALIGN (gnu_type))
1665 tree gnu_field_type, gnu_field;
1667 /* Set the RM size before wrapping up the type. */
1668 SET_TYPE_RM_SIZE (gnu_type,
1669 UI_To_gnu (RM_Size (gnat_entity), bitsizetype));
1670 gnu_field_type = gnu_type;
1672 gnu_type = make_node (RECORD_TYPE);
1673 TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "PAD");
1675 TYPE_ALIGN (gnu_type) = align;
1676 TYPE_PACKED (gnu_type) = 1;
1678 /* Create a stripped-down declaration of the original type, mainly
1680 create_type_decl (gnu_entity_name, gnu_field_type, NULL, true,
1681 debug_info_p, gnat_entity);
1683 /* Don't notify the field as "addressable", since we won't be taking
1684 it's address and it would prevent create_field_decl from making a
1686 gnu_field = create_field_decl (get_identifier ("OBJECT"),
1687 gnu_field_type, gnu_type, 1, 0, 0, 0);
1689 finish_record_type (gnu_type, gnu_field, 0, false);
1690 TYPE_IS_PADDING_P (gnu_type) = 1;
1692 relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY);
1695 /* Otherwise reset the alignment lest we computed it above. */
1701 case E_Floating_Point_Type:
1702 /* If this is a VAX floating-point type, use an integer of the proper
1703 size. All the operations will be handled with ASM statements. */
1704 if (Vax_Float (gnat_entity))
1706 gnu_type = make_signed_type (esize);
1707 TYPE_VAX_FLOATING_POINT_P (gnu_type) = 1;
1708 SET_TYPE_DIGITS_VALUE (gnu_type,
1709 UI_To_gnu (Digits_Value (gnat_entity),
1714 /* The type of the Low and High bounds can be our type if this is
1715 a type from Standard, so set them at the end of the function. */
1716 gnu_type = make_node (REAL_TYPE);
1717 TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize);
1718 layout_type (gnu_type);
1721 case E_Floating_Point_Subtype:
1722 if (Vax_Float (gnat_entity))
1724 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
1730 && Present (Ancestor_Subtype (gnat_entity))
1731 && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity))
1732 && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity))
1733 || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity))))
1734 gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity),
1737 gnu_type = make_node (REAL_TYPE);
1738 TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity));
1739 TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize);
1740 TYPE_GCC_MIN_VALUE (gnu_type)
1741 = TYPE_GCC_MIN_VALUE (TREE_TYPE (gnu_type));
1742 TYPE_GCC_MAX_VALUE (gnu_type)
1743 = TYPE_GCC_MAX_VALUE (TREE_TYPE (gnu_type));
1744 layout_type (gnu_type);
1746 SET_TYPE_RM_MIN_VALUE
1748 convert (TREE_TYPE (gnu_type),
1749 elaborate_expression (Type_Low_Bound (gnat_entity),
1750 gnat_entity, get_identifier ("L"),
1752 Needs_Debug_Info (gnat_entity))));
1754 SET_TYPE_RM_MAX_VALUE
1756 convert (TREE_TYPE (gnu_type),
1757 elaborate_expression (Type_High_Bound (gnat_entity),
1758 gnat_entity, get_identifier ("U"),
1760 Needs_Debug_Info (gnat_entity))));
1762 /* One of the above calls might have caused us to be elaborated,
1763 so don't blow up if so. */
1764 if (present_gnu_tree (gnat_entity))
1766 maybe_present = true;
1770 /* Inherit our alias set from what we're a subtype of, as for
1771 integer subtypes. */
1772 relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY);
1776 /* Array and String Types and Subtypes
1778 Unconstrained array types are represented by E_Array_Type and
1779 constrained array types are represented by E_Array_Subtype. There
1780 are no actual objects of an unconstrained array type; all we have
1781 are pointers to that type.
1783 The following fields are defined on array types and subtypes:
1785 Component_Type Component type of the array.
1786 Number_Dimensions Number of dimensions (an int).
1787 First_Index Type of first index. */
1792 Entity_Id gnat_ind_subtype;
1793 Entity_Id gnat_ind_base_subtype;
1794 int ndim = Number_Dimensions (gnat_entity);
1796 = (Convention (gnat_entity) == Convention_Fortran) ? ndim - 1 : 0;
1798 = (Convention (gnat_entity) == Convention_Fortran) ? - 1 : 1;
1800 tree gnu_template_fields = NULL_TREE;
1801 tree gnu_template_type = make_node (RECORD_TYPE);
1802 tree gnu_template_reference;
1803 tree gnu_ptr_template = build_pointer_type (gnu_template_type);
1804 tree gnu_fat_type = make_node (RECORD_TYPE);
1805 tree *gnu_index_types = (tree *) alloca (ndim * sizeof (tree));
1806 tree *gnu_temp_fields = (tree *) alloca (ndim * sizeof (tree));
1807 tree gnu_max_size = size_one_node, gnu_max_size_unit;
1808 tree gnu_comp_size, tem;
1810 TYPE_NAME (gnu_template_type)
1811 = create_concat_name (gnat_entity, "XUB");
1813 /* Make a node for the array. If we are not defining the array
1814 suppress expanding incomplete types. */
1815 gnu_type = make_node (UNCONSTRAINED_ARRAY_TYPE);
1818 defer_incomplete_level++, this_deferred = true;
1820 /* Build the fat pointer type. Use a "void *" object instead of
1821 a pointer to the array type since we don't have the array type
1822 yet (it will reference the fat pointer via the bounds). */
1823 tem = chainon (chainon (NULL_TREE,
1824 create_field_decl (get_identifier ("P_ARRAY"),
1826 gnu_fat_type, 0, 0, 0, 0)),
1827 create_field_decl (get_identifier ("P_BOUNDS"),
1829 gnu_fat_type, 0, 0, 0, 0));
1831 /* Make sure we can put this into a register. */
1832 TYPE_ALIGN (gnu_fat_type) = MIN (BIGGEST_ALIGNMENT, 2 * POINTER_SIZE);
1834 /* Do not finalize this record type since the types of its fields
1835 are still incomplete at this point. */
1836 finish_record_type (gnu_fat_type, tem, 0, true);
1837 TYPE_IS_FAT_POINTER_P (gnu_fat_type) = 1;
1839 /* Build a reference to the template from a PLACEHOLDER_EXPR that
1840 is the fat pointer. This will be used to access the individual
1841 fields once we build them. */
1842 tem = build3 (COMPONENT_REF, gnu_ptr_template,
1843 build0 (PLACEHOLDER_EXPR, gnu_fat_type),
1844 TREE_CHAIN (TYPE_FIELDS (gnu_fat_type)), NULL_TREE);
1845 gnu_template_reference
1846 = build_unary_op (INDIRECT_REF, gnu_template_type, tem);
1847 TREE_READONLY (gnu_template_reference) = 1;
1849 /* Now create the GCC type for each index and add the fields for
1850 that index to the template. */
1851 for (index = first_dim, gnat_ind_subtype = First_Index (gnat_entity),
1852 gnat_ind_base_subtype
1853 = First_Index (Implementation_Base_Type (gnat_entity));
1854 index < ndim && index >= 0;
1856 gnat_ind_subtype = Next_Index (gnat_ind_subtype),
1857 gnat_ind_base_subtype = Next_Index (gnat_ind_base_subtype))
1859 char field_name[10];
1860 tree gnu_ind_subtype
1861 = get_unpadded_type (Base_Type (Etype (gnat_ind_subtype)));
1862 tree gnu_base_subtype
1863 = get_unpadded_type (Etype (gnat_ind_base_subtype));
1865 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_subtype));
1867 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_subtype));
1868 tree gnu_min_field, gnu_max_field, gnu_min, gnu_max;
1870 /* Make the FIELD_DECLs for the minimum and maximum of this
1871 type and then make extractions of that field from the
1873 sprintf (field_name, "LB%d", index);
1874 gnu_min_field = create_field_decl (get_identifier (field_name),
1876 gnu_template_type, 0, 0, 0, 0);
1877 field_name[0] = 'U';
1878 gnu_max_field = create_field_decl (get_identifier (field_name),
1880 gnu_template_type, 0, 0, 0, 0);
1882 Sloc_to_locus (Sloc (gnat_entity),
1883 &DECL_SOURCE_LOCATION (gnu_min_field));
1884 Sloc_to_locus (Sloc (gnat_entity),
1885 &DECL_SOURCE_LOCATION (gnu_max_field));
1886 gnu_temp_fields[index] = chainon (gnu_min_field, gnu_max_field);
1888 /* We can't use build_component_ref here since the template
1889 type isn't complete yet. */
1890 gnu_min = build3 (COMPONENT_REF, gnu_ind_subtype,
1891 gnu_template_reference, gnu_min_field,
1893 gnu_max = build3 (COMPONENT_REF, gnu_ind_subtype,
1894 gnu_template_reference, gnu_max_field,
1896 TREE_READONLY (gnu_min) = TREE_READONLY (gnu_max) = 1;
1898 /* Make a range type with the new ranges, but using
1899 the Ada subtype. Then we convert to sizetype. */
1900 gnu_index_types[index]
1901 = create_index_type (convert (sizetype, gnu_min),
1902 convert (sizetype, gnu_max),
1903 create_range_type (gnu_ind_subtype,
1906 /* Update the maximum size of the array, in elements. */
1908 = size_binop (MULT_EXPR, gnu_max_size,
1909 size_binop (PLUS_EXPR, size_one_node,
1910 size_binop (MINUS_EXPR, gnu_base_max,
1913 TYPE_NAME (gnu_index_types[index])
1914 = create_concat_name (gnat_entity, field_name);
1917 for (index = 0; index < ndim; index++)
1919 = chainon (gnu_template_fields, gnu_temp_fields[index]);
1921 /* Install all the fields into the template. */
1922 finish_record_type (gnu_template_type, gnu_template_fields, 0, false);
1923 TYPE_READONLY (gnu_template_type) = 1;
1925 /* Now make the array of arrays and update the pointer to the array
1926 in the fat pointer. Note that it is the first field. */
1927 tem = gnat_to_gnu_type (Component_Type (gnat_entity));
1929 /* Try to get a smaller form of the component if needed. */
1930 if ((Is_Packed (gnat_entity)
1931 || Has_Component_Size_Clause (gnat_entity))
1932 && !Is_Bit_Packed_Array (gnat_entity)
1933 && !Has_Aliased_Components (gnat_entity)
1934 && !Strict_Alignment (Component_Type (gnat_entity))
1935 && TREE_CODE (tem) == RECORD_TYPE
1936 && !TYPE_IS_FAT_POINTER_P (tem)
1937 && host_integerp (TYPE_SIZE (tem), 1))
1938 tem = make_packable_type (tem, false);
1940 if (Has_Atomic_Components (gnat_entity))
1941 check_ok_for_atomic (tem, gnat_entity, true);
1943 /* Get and validate any specified Component_Size, but if Packed,
1944 ignore it since the front end will have taken care of it. */
1946 = validate_size (Component_Size (gnat_entity), tem,
1948 (Is_Bit_Packed_Array (gnat_entity)
1949 ? TYPE_DECL : VAR_DECL),
1950 true, Has_Component_Size_Clause (gnat_entity));
1952 /* If the component type is a RECORD_TYPE that has a self-referential
1953 size, use the maximum size. */
1955 && TREE_CODE (tem) == RECORD_TYPE
1956 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (tem)))
1957 gnu_comp_size = max_size (TYPE_SIZE (tem), true);
1959 if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_entity))
1961 tree orig_tem = tem;
1962 unsigned int max_align;
1964 /* If an alignment is specified, use it as a cap on the component
1965 type so that it can be honored for the whole type. But ignore
1966 it for the original type of packed array types. */
1967 if (No (Packed_Array_Type (gnat_entity))
1968 && Known_Alignment (gnat_entity))
1969 max_align = validate_alignment (Alignment (gnat_entity),
1974 tem = make_type_from_size (tem, gnu_comp_size, false);
1975 if (max_align > 0 && TYPE_ALIGN (tem) > max_align)
1980 tem = maybe_pad_type (tem, gnu_comp_size, 0, gnat_entity,
1981 "C_PAD", false, definition, true);
1983 /* If a padding record was made, declare it now since it will
1984 never be declared otherwise. This is necessary to ensure
1985 that its subtrees are properly marked. */
1986 if (tem != orig_tem)
1987 create_type_decl (TYPE_NAME (tem), tem, NULL, true,
1988 debug_info_p, gnat_entity);
1991 if (Has_Volatile_Components (gnat_entity))
1992 tem = build_qualified_type (tem,
1993 TYPE_QUALS (tem) | TYPE_QUAL_VOLATILE);
1995 /* If Component_Size is not already specified, annotate it with the
1996 size of the component. */
1997 if (Unknown_Component_Size (gnat_entity))
1998 Set_Component_Size (gnat_entity, annotate_value (TYPE_SIZE (tem)));
2000 gnu_max_size_unit = size_binop (MAX_EXPR, size_zero_node,
2001 size_binop (MULT_EXPR, gnu_max_size,
2002 TYPE_SIZE_UNIT (tem)));
2003 gnu_max_size = size_binop (MAX_EXPR, bitsize_zero_node,
2004 size_binop (MULT_EXPR,
2005 convert (bitsizetype,
2009 for (index = ndim - 1; index >= 0; index--)
2011 tem = build_array_type (tem, gnu_index_types[index]);
2012 TYPE_MULTI_ARRAY_P (tem) = (index > 0);
2013 if (array_type_has_nonaliased_component (gnat_entity, tem))
2014 TYPE_NONALIASED_COMPONENT (tem) = 1;
2017 /* If an alignment is specified, use it if valid. But ignore it
2018 for the original type of packed array types. If the alignment
2019 was requested with an explicit alignment clause, state so. */
2020 if (No (Packed_Array_Type (gnat_entity))
2021 && Known_Alignment (gnat_entity))
2024 = validate_alignment (Alignment (gnat_entity), gnat_entity,
2026 if (Present (Alignment_Clause (gnat_entity)))
2027 TYPE_USER_ALIGN (tem) = 1;
2030 TYPE_CONVENTION_FORTRAN_P (tem)
2031 = (Convention (gnat_entity) == Convention_Fortran);
2032 TREE_TYPE (TYPE_FIELDS (gnu_fat_type)) = build_pointer_type (tem);
2034 /* The result type is an UNCONSTRAINED_ARRAY_TYPE that indicates the
2035 corresponding fat pointer. */
2036 TREE_TYPE (gnu_type) = TYPE_POINTER_TO (gnu_type)
2037 = TYPE_REFERENCE_TO (gnu_type) = gnu_fat_type;
2038 SET_TYPE_MODE (gnu_type, BLKmode);
2039 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (tem);
2040 SET_TYPE_UNCONSTRAINED_ARRAY (gnu_fat_type, gnu_type);
2042 /* If the maximum size doesn't overflow, use it. */
2043 if (TREE_CODE (gnu_max_size) == INTEGER_CST
2044 && !TREE_OVERFLOW (gnu_max_size))
2046 = size_binop (MIN_EXPR, gnu_max_size, TYPE_SIZE (tem));
2047 if (TREE_CODE (gnu_max_size_unit) == INTEGER_CST
2048 && !TREE_OVERFLOW (gnu_max_size_unit))
2049 TYPE_SIZE_UNIT (tem)
2050 = size_binop (MIN_EXPR, gnu_max_size_unit,
2051 TYPE_SIZE_UNIT (tem));
2053 create_type_decl (create_concat_name (gnat_entity, "XUA"),
2054 tem, NULL, !Comes_From_Source (gnat_entity),
2055 debug_info_p, gnat_entity);
2057 /* Give the fat pointer type a name. */
2058 create_type_decl (create_concat_name (gnat_entity, "XUP"),
2059 gnu_fat_type, NULL, true,
2060 debug_info_p, gnat_entity);
2062 /* Create the type to be used as what a thin pointer designates: an
2063 record type for the object and its template with the field offsets
2064 shifted to have the template at a negative offset. */
2065 tem = build_unc_object_type (gnu_template_type, tem,
2066 create_concat_name (gnat_entity, "XUT"));
2067 shift_unc_components_for_thin_pointers (tem);
2069 SET_TYPE_UNCONSTRAINED_ARRAY (tem, gnu_type);
2070 TYPE_OBJECT_RECORD_TYPE (gnu_type) = tem;
2072 /* Give the thin pointer type a name. */
2073 create_type_decl (create_concat_name (gnat_entity, "XUX"),
2074 build_pointer_type (tem), NULL, true,
2075 debug_info_p, gnat_entity);
2079 case E_String_Subtype:
2080 case E_Array_Subtype:
2082 /* This is the actual data type for array variables. Multidimensional
2083 arrays are implemented in the gnu tree as arrays of arrays. Note
2084 that for the moment arrays which have sparse enumeration subtypes as
2085 index components create sparse arrays, which is obviously space
2086 inefficient but so much easier to code for now.
2088 Also note that the subtype never refers to the unconstrained
2089 array type, which is somewhat at variance with Ada semantics.
2091 First check to see if this is simply a renaming of the array
2092 type. If so, the result is the array type. */
2094 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
2095 if (!Is_Constrained (gnat_entity))
2099 Entity_Id gnat_ind_subtype;
2100 Entity_Id gnat_ind_base_subtype;
2101 int dim = Number_Dimensions (gnat_entity);
2103 = (Convention (gnat_entity) == Convention_Fortran) ? dim - 1 : 0;
2105 = (Convention (gnat_entity) == Convention_Fortran) ? -1 : 1;
2107 tree gnu_base_type = gnu_type;
2108 tree *gnu_index_type = (tree *) alloca (dim * sizeof (tree));
2109 tree gnu_max_size = size_one_node, gnu_max_size_unit;
2110 bool need_index_type_struct = false;
2111 bool max_overflow = false;
2113 /* First create the gnu types for each index. Create types for
2114 debugging information to point to the index types if the
2115 are not integer types, have variable bounds, or are
2116 wider than sizetype. */
2118 for (index = first_dim, gnat_ind_subtype = First_Index (gnat_entity),
2119 gnat_ind_base_subtype
2120 = First_Index (Implementation_Base_Type (gnat_entity));
2121 index < dim && index >= 0;
2123 gnat_ind_subtype = Next_Index (gnat_ind_subtype),
2124 gnat_ind_base_subtype = Next_Index (gnat_ind_base_subtype))
2126 tree gnu_index_subtype
2127 = get_unpadded_type (Etype (gnat_ind_subtype));
2129 = convert (sizetype, TYPE_MIN_VALUE (gnu_index_subtype));
2131 = convert (sizetype, TYPE_MAX_VALUE (gnu_index_subtype));
2132 tree gnu_base_subtype
2133 = get_unpadded_type (Etype (gnat_ind_base_subtype));
2135 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_subtype));
2137 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_subtype));
2138 tree gnu_base_type = get_base_type (gnu_base_subtype);
2139 tree gnu_base_base_min
2140 = convert (sizetype, TYPE_MIN_VALUE (gnu_base_type));
2141 tree gnu_base_base_max
2142 = convert (sizetype, TYPE_MAX_VALUE (gnu_base_type));
2146 /* If the minimum and maximum values both overflow in
2147 SIZETYPE, but the difference in the original type
2148 does not overflow in SIZETYPE, ignore the overflow
2150 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)
2158 (fold_build2 (MINUS_EXPR, gnu_index_subtype,
2159 TYPE_MAX_VALUE (gnu_index_subtype),
2160 TYPE_MIN_VALUE (gnu_index_subtype))))
2162 TREE_OVERFLOW (gnu_min) = 0;
2163 TREE_OVERFLOW (gnu_max) = 0;
2164 if (tree_int_cst_lt (gnu_max, gnu_min))
2166 gnu_min = size_one_node;
2167 gnu_max = size_zero_node;
2172 /* Similarly, if the range is null, use bounds of 1..0 for
2173 the sizetype bounds. */
2174 else if ((TYPE_PRECISION (gnu_index_subtype)
2175 > TYPE_PRECISION (sizetype)
2176 || TYPE_UNSIGNED (gnu_index_subtype)
2177 != TYPE_UNSIGNED (sizetype))
2178 && TREE_CODE (gnu_min) == INTEGER_CST
2179 && TREE_CODE (gnu_max) == INTEGER_CST
2180 && (TREE_OVERFLOW (gnu_min) || TREE_OVERFLOW (gnu_max))
2181 && tree_int_cst_lt (TYPE_MAX_VALUE (gnu_index_subtype),
2182 TYPE_MIN_VALUE (gnu_index_subtype)))
2184 gnu_min = size_one_node;
2185 gnu_max = size_zero_node;
2189 /* See if the base array type is already flat. If it is, we
2190 are probably compiling an ACATS test, but it will cause the
2191 code below to malfunction if we don't handle it specially. */
2192 else if (TREE_CODE (gnu_base_min) == INTEGER_CST
2193 && TREE_CODE (gnu_base_max) == INTEGER_CST
2194 && !TREE_OVERFLOW (gnu_base_min)
2195 && !TREE_OVERFLOW (gnu_base_max)
2196 && tree_int_cst_lt (gnu_base_max, gnu_base_min))
2198 gnu_min = size_one_node;
2199 gnu_max = size_zero_node;
2205 /* Now compute the size of this bound. We need to provide
2206 GCC with an upper bound to use but have to deal with the
2207 "superflat" case. There are three ways to do this. If
2208 we can prove that the array can never be superflat, we
2209 can just use the high bound of the index subtype. If we
2210 can prove that the low bound minus one can't overflow,
2211 we can do this as MAX (hb, lb - 1). Otherwise, we have
2212 to use the expression hb >= lb ? hb : lb - 1. */
2213 gnu_high = size_binop (MINUS_EXPR, gnu_min, size_one_node);
2215 /* If gnu_high is now an integer which overflowed, the array
2216 cannot be superflat. */
2217 if (TREE_CODE (gnu_high) == INTEGER_CST
2218 && TREE_OVERFLOW (gnu_high))
2221 /* gnu_high cannot overflow if the subtype is unsigned since
2222 sizetype is signed, or if it is now a constant that hasn't
2224 else if (TYPE_UNSIGNED (gnu_base_subtype)
2225 || TREE_CODE (gnu_high) == INTEGER_CST)
2226 gnu_high = size_binop (MAX_EXPR, gnu_max, gnu_high);
2230 = build_cond_expr (sizetype,
2231 build_binary_op (GE_EXPR,
2237 gnu_index_type[index]
2238 = create_index_type (gnu_min, gnu_high, gnu_index_subtype,
2241 /* Also compute the maximum size of the array. Here we
2242 see if any constraint on the index type of the base type
2243 can be used in the case of self-referential bound on
2244 the index type of the subtype. We look for a non-"infinite"
2245 and non-self-referential bound from any type involved and
2246 handle each bound separately. */
2248 if ((TREE_CODE (gnu_min) == INTEGER_CST
2249 && !TREE_OVERFLOW (gnu_min)
2250 && !operand_equal_p (gnu_min, gnu_base_base_min, 0))
2251 || !CONTAINS_PLACEHOLDER_P (gnu_min)
2252 || !(TREE_CODE (gnu_base_min) == INTEGER_CST
2253 && !TREE_OVERFLOW (gnu_base_min)))
2254 gnu_base_min = gnu_min;
2256 if ((TREE_CODE (gnu_max) == INTEGER_CST
2257 && !TREE_OVERFLOW (gnu_max)
2258 && !operand_equal_p (gnu_max, gnu_base_base_max, 0))
2259 || !CONTAINS_PLACEHOLDER_P (gnu_max)
2260 || !(TREE_CODE (gnu_base_max) == INTEGER_CST
2261 && !TREE_OVERFLOW (gnu_base_max)))
2262 gnu_base_max = gnu_max;
2264 if ((TREE_CODE (gnu_base_min) == INTEGER_CST
2265 && TREE_OVERFLOW (gnu_base_min))
2266 || operand_equal_p (gnu_base_min, gnu_base_base_min, 0)
2267 || (TREE_CODE (gnu_base_max) == INTEGER_CST
2268 && TREE_OVERFLOW (gnu_base_max))
2269 || operand_equal_p (gnu_base_max, gnu_base_base_max, 0))
2270 max_overflow = true;
2272 gnu_base_min = size_binop (MAX_EXPR, gnu_base_min, gnu_min);
2273 gnu_base_max = size_binop (MIN_EXPR, gnu_base_max, gnu_max);
2276 = size_binop (MAX_EXPR,
2277 size_binop (PLUS_EXPR, size_one_node,
2278 size_binop (MINUS_EXPR, gnu_base_max,
2282 if (TREE_CODE (gnu_this_max) == INTEGER_CST
2283 && TREE_OVERFLOW (gnu_this_max))
2284 max_overflow = true;
2287 = size_binop (MULT_EXPR, gnu_max_size, gnu_this_max);
2289 if (!integer_onep (TYPE_MIN_VALUE (gnu_index_subtype))
2290 || (TREE_CODE (TYPE_MAX_VALUE (gnu_index_subtype))
2292 || TREE_CODE (gnu_index_subtype) != INTEGER_TYPE
2293 || (TREE_TYPE (gnu_index_subtype)
2294 && (TREE_CODE (TREE_TYPE (gnu_index_subtype))
2296 || TYPE_BIASED_REPRESENTATION_P (gnu_index_subtype)
2297 || (TYPE_PRECISION (gnu_index_subtype)
2298 > TYPE_PRECISION (sizetype)))
2299 need_index_type_struct = true;
2302 /* Then flatten: create the array of arrays. For an array type
2303 used to implement a packed array, get the component type from
2304 the original array type since the representation clauses that
2305 can affect it are on the latter. */
2306 if (Is_Packed_Array_Type (gnat_entity)
2307 && !Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))
2309 gnu_type = gnat_to_gnu_type (Original_Array_Type (gnat_entity));
2310 for (index = dim - 1; index >= 0; index--)
2311 gnu_type = TREE_TYPE (gnu_type);
2313 /* One of the above calls might have caused us to be elaborated,
2314 so don't blow up if so. */
2315 if (present_gnu_tree (gnat_entity))
2317 maybe_present = true;
2325 gnu_type = gnat_to_gnu_type (Component_Type (gnat_entity));
2327 /* One of the above calls might have caused us to be elaborated,
2328 so don't blow up if so. */
2329 if (present_gnu_tree (gnat_entity))
2331 maybe_present = true;
2335 /* Try to get a smaller form of the component if needed. */
2336 if ((Is_Packed (gnat_entity)
2337 || Has_Component_Size_Clause (gnat_entity))
2338 && !Is_Bit_Packed_Array (gnat_entity)
2339 && !Has_Aliased_Components (gnat_entity)
2340 && !Strict_Alignment (Component_Type (gnat_entity))
2341 && TREE_CODE (gnu_type) == RECORD_TYPE
2342 && !TYPE_IS_FAT_POINTER_P (gnu_type)
2343 && host_integerp (TYPE_SIZE (gnu_type), 1))
2344 gnu_type = make_packable_type (gnu_type, false);
2346 /* Get and validate any specified Component_Size, but if Packed,
2347 ignore it since the front end will have taken care of it. */
2349 = validate_size (Component_Size (gnat_entity), gnu_type,
2351 (Is_Bit_Packed_Array (gnat_entity)
2352 ? TYPE_DECL : VAR_DECL), true,
2353 Has_Component_Size_Clause (gnat_entity));
2355 /* If the component type is a RECORD_TYPE that has a
2356 self-referential size, use the maximum size. */
2358 && TREE_CODE (gnu_type) == RECORD_TYPE
2359 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
2360 gnu_comp_size = max_size (TYPE_SIZE (gnu_type), true);
2362 if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_entity))
2364 tree orig_gnu_type = gnu_type;
2365 unsigned int max_align;
2367 /* If an alignment is specified, use it as a cap on the
2368 component type so that it can be honored for the whole
2369 type. But ignore it for the original type of packed
2371 if (No (Packed_Array_Type (gnat_entity))
2372 && Known_Alignment (gnat_entity))
2373 max_align = validate_alignment (Alignment (gnat_entity),
2379 = make_type_from_size (gnu_type, gnu_comp_size, false);
2380 if (max_align > 0 && TYPE_ALIGN (gnu_type) > max_align)
2381 gnu_type = orig_gnu_type;
2383 orig_gnu_type = gnu_type;
2385 gnu_type = maybe_pad_type (gnu_type, gnu_comp_size, 0,
2386 gnat_entity, "C_PAD", false,
2389 /* If a padding record was made, declare it now since it
2390 will never be declared otherwise. This is necessary
2391 to ensure that its subtrees are properly marked. */
2392 if (gnu_type != orig_gnu_type)
2393 create_type_decl (TYPE_NAME (gnu_type), gnu_type, NULL,
2394 true, debug_info_p, gnat_entity);
2397 if (Has_Volatile_Components (Base_Type (gnat_entity)))
2398 gnu_type = build_qualified_type (gnu_type,
2399 (TYPE_QUALS (gnu_type)
2400 | TYPE_QUAL_VOLATILE));
2403 gnu_max_size_unit = size_binop (MULT_EXPR, gnu_max_size,
2404 TYPE_SIZE_UNIT (gnu_type));
2405 gnu_max_size = size_binop (MULT_EXPR,
2406 convert (bitsizetype, gnu_max_size),
2407 TYPE_SIZE (gnu_type));
2409 for (index = dim - 1; index >= 0; index --)
2411 gnu_type = build_array_type (gnu_type, gnu_index_type[index]);
2412 TYPE_MULTI_ARRAY_P (gnu_type) = (index > 0);
2413 if (array_type_has_nonaliased_component (gnat_entity, gnu_type))
2414 TYPE_NONALIASED_COMPONENT (gnu_type) = 1;
2417 /* Attach the TYPE_STUB_DECL in case we have a parallel type. */
2418 TYPE_STUB_DECL (gnu_type)
2419 = create_type_stub_decl (gnu_entity_name, gnu_type);
2421 /* If we are at file level and this is a multi-dimensional array, we
2422 need to make a variable corresponding to the stride of the
2423 inner dimensions. */
2424 if (global_bindings_p () && dim > 1)
2426 tree gnu_str_name = get_identifier ("ST");
2429 for (gnu_arr_type = TREE_TYPE (gnu_type);
2430 TREE_CODE (gnu_arr_type) == ARRAY_TYPE;
2431 gnu_arr_type = TREE_TYPE (gnu_arr_type),
2432 gnu_str_name = concat_name (gnu_str_name, "ST"))
2434 tree eltype = TREE_TYPE (gnu_arr_type);
2436 TYPE_SIZE (gnu_arr_type)
2437 = elaborate_expression_1 (TYPE_SIZE (gnu_arr_type),
2438 gnat_entity, gnu_str_name,
2441 /* ??? For now, store the size as a multiple of the
2442 alignment of the element type in bytes so that we
2443 can see the alignment from the tree. */
2444 TYPE_SIZE_UNIT (gnu_arr_type)
2446 (MULT_EXPR, sizetype,
2447 elaborate_expression_1
2448 (build_binary_op (EXACT_DIV_EXPR, sizetype,
2449 TYPE_SIZE_UNIT (gnu_arr_type),
2450 size_int (TYPE_ALIGN (eltype)
2452 gnat_entity, concat_name (gnu_str_name, "A_U"),
2454 size_int (TYPE_ALIGN (eltype) / BITS_PER_UNIT));
2456 /* ??? create_type_decl is not invoked on the inner types so
2457 the MULT_EXPR node built above will never be marked. */
2458 mark_visited (&TYPE_SIZE_UNIT (gnu_arr_type));
2462 /* If we need to write out a record type giving the names of the
2463 bounds for debugging purposes, do it now and make the record
2464 type a parallel type. This is not needed for a packed array
2465 since the bounds are conveyed by the original array type. */
2466 if (need_index_type_struct
2468 && !Is_Packed_Array_Type (gnat_entity))
2470 tree gnu_bound_rec = make_node (RECORD_TYPE);
2471 tree gnu_field_list = NULL_TREE;
2474 TYPE_NAME (gnu_bound_rec)
2475 = create_concat_name (gnat_entity, "XA");
2477 for (index = dim - 1; index >= 0; index--)
2479 tree gnu_index = TYPE_INDEX_TYPE (gnu_index_type[index]);
2480 tree gnu_index_name = TYPE_NAME (gnu_index);
2482 if (TREE_CODE (gnu_index_name) == TYPE_DECL)
2483 gnu_index_name = DECL_NAME (gnu_index_name);
2485 /* Make sure to reference the types themselves, and not just
2486 their names, as the debugger may fall back on them. */
2487 gnu_field = create_field_decl (gnu_index_name, gnu_index,
2489 0, NULL_TREE, NULL_TREE, 0);
2490 TREE_CHAIN (gnu_field) = gnu_field_list;
2491 gnu_field_list = gnu_field;
2494 finish_record_type (gnu_bound_rec, gnu_field_list, 0, false);
2495 add_parallel_type (TYPE_STUB_DECL (gnu_type), gnu_bound_rec);
2498 /* Otherwise, for a packed array, make the original array type a
2500 else if (debug_info_p
2501 && Is_Packed_Array_Type (gnat_entity)
2502 && present_gnu_tree (Original_Array_Type (gnat_entity)))
2503 add_parallel_type (TYPE_STUB_DECL (gnu_type),
2505 (Original_Array_Type (gnat_entity)));
2507 TYPE_CONVENTION_FORTRAN_P (gnu_type)
2508 = (Convention (gnat_entity) == Convention_Fortran);
2509 TYPE_PACKED_ARRAY_TYPE_P (gnu_type)
2510 = (Is_Packed_Array_Type (gnat_entity)
2511 && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)));
2513 /* If our size depends on a placeholder and the maximum size doesn't
2514 overflow, use it. */
2515 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))
2516 && !(TREE_CODE (gnu_max_size) == INTEGER_CST
2517 && TREE_OVERFLOW (gnu_max_size))
2518 && !(TREE_CODE (gnu_max_size_unit) == INTEGER_CST
2519 && TREE_OVERFLOW (gnu_max_size_unit))
2522 TYPE_SIZE (gnu_type) = size_binop (MIN_EXPR, gnu_max_size,
2523 TYPE_SIZE (gnu_type));
2524 TYPE_SIZE_UNIT (gnu_type)
2525 = size_binop (MIN_EXPR, gnu_max_size_unit,
2526 TYPE_SIZE_UNIT (gnu_type));
2529 /* Set our alias set to that of our base type. This gives all
2530 array subtypes the same alias set. */
2531 relate_alias_sets (gnu_type, gnu_base_type, ALIAS_SET_COPY);
2534 /* If this is a packed type, make this type the same as the packed
2535 array type, but do some adjusting in the type first. */
2536 if (Present (Packed_Array_Type (gnat_entity)))
2538 Entity_Id gnat_index;
2539 tree gnu_inner_type;
2541 /* First finish the type we had been making so that we output
2542 debugging information for it. */
2544 = build_qualified_type (gnu_type,
2545 (TYPE_QUALS (gnu_type)
2546 | (TYPE_QUAL_VOLATILE
2547 * Treat_As_Volatile (gnat_entity))));
2549 /* Make it artificial only if the base type was artificial as well.
2550 That's sort of "morally" true and will make it possible for the
2551 debugger to look it up by name in DWARF, which is necessary in
2552 order to decode the packed array type. */
2554 = create_type_decl (gnu_entity_name, gnu_type, attr_list,
2555 !Comes_From_Source (gnat_entity)
2556 && !Comes_From_Source (Etype (gnat_entity)),
2557 debug_info_p, gnat_entity);
2559 /* Save it as our equivalent in case the call below elaborates
2561 save_gnu_tree (gnat_entity, gnu_decl, false);
2563 gnu_decl = gnat_to_gnu_entity (Packed_Array_Type (gnat_entity),
2565 this_made_decl = true;
2566 gnu_type = TREE_TYPE (gnu_decl);
2567 save_gnu_tree (gnat_entity, NULL_TREE, false);
2569 gnu_inner_type = gnu_type;
2570 while (TREE_CODE (gnu_inner_type) == RECORD_TYPE
2571 && (TYPE_JUSTIFIED_MODULAR_P (gnu_inner_type)
2572 || TYPE_IS_PADDING_P (gnu_inner_type)))
2573 gnu_inner_type = TREE_TYPE (TYPE_FIELDS (gnu_inner_type));
2575 /* We need to attach the index type to the type we just made so
2576 that the actual bounds can later be put into a template. */
2577 if ((TREE_CODE (gnu_inner_type) == ARRAY_TYPE
2578 && !TYPE_ACTUAL_BOUNDS (gnu_inner_type))
2579 || (TREE_CODE (gnu_inner_type) == INTEGER_TYPE
2580 && !TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner_type)))
2582 if (TREE_CODE (gnu_inner_type) == INTEGER_TYPE)
2584 /* The TYPE_ACTUAL_BOUNDS field is overloaded with the
2585 TYPE_MODULUS for modular types so we make an extra
2586 subtype if necessary. */
2587 if (TYPE_MODULAR_P (gnu_inner_type))
2590 = make_unsigned_type (TYPE_PRECISION (gnu_inner_type));
2591 TREE_TYPE (gnu_subtype) = gnu_inner_type;
2592 TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1;
2593 SET_TYPE_RM_MIN_VALUE (gnu_subtype,
2594 TYPE_MIN_VALUE (gnu_inner_type));
2595 SET_TYPE_RM_MAX_VALUE (gnu_subtype,
2596 TYPE_MAX_VALUE (gnu_inner_type));
2597 gnu_inner_type = gnu_subtype;
2600 TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner_type) = 1;
2602 #ifdef ENABLE_CHECKING
2603 /* Check for other cases of overloading. */
2604 gcc_assert (!TYPE_ACTUAL_BOUNDS (gnu_inner_type));
2608 /* ??? This is necessary to make sure that the container is
2609 allocated with a null tree upfront; otherwise, it could
2610 be allocated with an uninitialized tree that is accessed
2611 before being set below. See ada-tree.h for details. */
2612 SET_TYPE_ACTUAL_BOUNDS (gnu_inner_type, NULL_TREE);
2614 for (gnat_index = First_Index (gnat_entity);
2615 Present (gnat_index); gnat_index = Next_Index (gnat_index))
2616 SET_TYPE_ACTUAL_BOUNDS
2618 tree_cons (NULL_TREE,
2619 get_unpadded_type (Etype (gnat_index)),
2620 TYPE_ACTUAL_BOUNDS (gnu_inner_type)));
2622 if (Convention (gnat_entity) != Convention_Fortran)
2623 SET_TYPE_ACTUAL_BOUNDS
2625 nreverse (TYPE_ACTUAL_BOUNDS (gnu_inner_type)));
2627 if (TREE_CODE (gnu_type) == RECORD_TYPE
2628 && TYPE_JUSTIFIED_MODULAR_P (gnu_type))
2629 TREE_TYPE (TYPE_FIELDS (gnu_type)) = gnu_inner_type;
2633 /* Abort if packed array with no packed array type field set. */
2635 gcc_assert (!Is_Packed (gnat_entity));
2639 case E_String_Literal_Subtype:
2640 /* Create the type for a string literal. */
2642 Entity_Id gnat_full_type
2643 = (IN (Ekind (Etype (gnat_entity)), Private_Kind)
2644 && Present (Full_View (Etype (gnat_entity)))
2645 ? Full_View (Etype (gnat_entity)) : Etype (gnat_entity));
2646 tree gnu_string_type = get_unpadded_type (gnat_full_type);
2647 tree gnu_string_array_type
2648 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_string_type))));
2649 tree gnu_string_index_type
2650 = get_base_type (TREE_TYPE (TYPE_INDEX_TYPE
2651 (TYPE_DOMAIN (gnu_string_array_type))));
2652 tree gnu_lower_bound
2653 = convert (gnu_string_index_type,
2654 gnat_to_gnu (String_Literal_Low_Bound (gnat_entity)));
2655 int length = UI_To_Int (String_Literal_Length (gnat_entity));
2656 tree gnu_length = ssize_int (length - 1);
2657 tree gnu_upper_bound
2658 = build_binary_op (PLUS_EXPR, gnu_string_index_type,
2660 convert (gnu_string_index_type, gnu_length));
2662 = create_index_type (convert (sizetype, gnu_lower_bound),
2663 convert (sizetype, gnu_upper_bound),
2664 create_range_type (gnu_string_index_type,
2670 = build_array_type (gnat_to_gnu_type (Component_Type (gnat_entity)),
2672 if (array_type_has_nonaliased_component (gnat_entity, gnu_type))
2673 TYPE_NONALIASED_COMPONENT (gnu_type) = 1;
2674 relate_alias_sets (gnu_type, gnu_string_type, ALIAS_SET_COPY);
2678 /* Record Types and Subtypes
2680 The following fields are defined on record types:
2682 Has_Discriminants True if the record has discriminants
2683 First_Discriminant Points to head of list of discriminants
2684 First_Entity Points to head of list of fields
2685 Is_Tagged_Type True if the record is tagged
2687 Implementation of Ada records and discriminated records:
2689 A record type definition is transformed into the equivalent of a C
2690 struct definition. The fields that are the discriminants which are
2691 found in the Full_Type_Declaration node and the elements of the
2692 Component_List found in the Record_Type_Definition node. The
2693 Component_List can be a recursive structure since each Variant of
2694 the Variant_Part of the Component_List has a Component_List.
2696 Processing of a record type definition comprises starting the list of
2697 field declarations here from the discriminants and the calling the
2698 function components_to_record to add the rest of the fields from the
2699 component list and return the gnu type node. The function
2700 components_to_record will call itself recursively as it traverses
2704 if (Has_Complex_Representation (gnat_entity))
2707 = build_complex_type
2709 (Etype (Defining_Entity
2710 (First (Component_Items
2713 (Declaration_Node (gnat_entity)))))))));
2719 Node_Id full_definition = Declaration_Node (gnat_entity);
2720 Node_Id record_definition = Type_Definition (full_definition);
2721 Entity_Id gnat_field;
2723 tree gnu_field_list = NULL_TREE;
2724 tree gnu_get_parent;
2725 /* Set PACKED in keeping with gnat_to_gnu_field. */
2727 = Is_Packed (gnat_entity)
2729 : Component_Alignment (gnat_entity) == Calign_Storage_Unit
2731 : (Known_Alignment (gnat_entity)
2732 || (Strict_Alignment (gnat_entity)
2733 && Known_Static_Esize (gnat_entity)))
2736 bool has_rep = Has_Specified_Layout (gnat_entity);
2737 bool all_rep = has_rep;
2739 = (Is_Tagged_Type (gnat_entity)
2740 && Nkind (record_definition) == N_Derived_Type_Definition);
2742 /* See if all fields have a rep clause. Stop when we find one
2744 for (gnat_field = First_Entity (gnat_entity);
2745 Present (gnat_field) && all_rep;
2746 gnat_field = Next_Entity (gnat_field))
2747 if ((Ekind (gnat_field) == E_Component
2748 || Ekind (gnat_field) == E_Discriminant)
2749 && No (Component_Clause (gnat_field)))
2752 /* If this is a record extension, go a level further to find the
2753 record definition. Also, verify we have a Parent_Subtype. */
2756 if (!type_annotate_only
2757 || Present (Record_Extension_Part (record_definition)))
2758 record_definition = Record_Extension_Part (record_definition);
2760 gcc_assert (type_annotate_only
2761 || Present (Parent_Subtype (gnat_entity)));
2764 /* Make a node for the record. If we are not defining the record,
2765 suppress expanding incomplete types. */
2766 gnu_type = make_node (tree_code_for_record_type (gnat_entity));
2767 TYPE_NAME (gnu_type) = gnu_entity_name;
2768 TYPE_PACKED (gnu_type) = (packed != 0) || has_rep;
2771 defer_incomplete_level++, this_deferred = true;
2773 /* If both a size and rep clause was specified, put the size in
2774 the record type now so that it can get the proper mode. */
2775 if (has_rep && Known_Esize (gnat_entity))
2776 TYPE_SIZE (gnu_type) = UI_To_gnu (Esize (gnat_entity), sizetype);
2778 /* Always set the alignment here so that it can be used to
2779 set the mode, if it is making the alignment stricter. If
2780 it is invalid, it will be checked again below. If this is to
2781 be Atomic, choose a default alignment of a word unless we know
2782 the size and it's smaller. */
2783 if (Known_Alignment (gnat_entity))
2784 TYPE_ALIGN (gnu_type)
2785 = validate_alignment (Alignment (gnat_entity), gnat_entity, 0);
2786 else if (Is_Atomic (gnat_entity))
2787 TYPE_ALIGN (gnu_type)
2788 = esize >= BITS_PER_WORD ? BITS_PER_WORD : ceil_alignment (esize);
2789 /* If a type needs strict alignment, the minimum size will be the
2790 type size instead of the RM size (see validate_size). Cap the
2791 alignment, lest it causes this type size to become too large. */
2792 else if (Strict_Alignment (gnat_entity)
2793 && Known_Static_Esize (gnat_entity))
2795 unsigned int raw_size = UI_To_Int (Esize (gnat_entity));
2796 unsigned int raw_align = raw_size & -raw_size;
2797 if (raw_align < BIGGEST_ALIGNMENT)
2798 TYPE_ALIGN (gnu_type) = raw_align;
2801 TYPE_ALIGN (gnu_type) = 0;
2803 /* If we have a Parent_Subtype, make a field for the parent. If
2804 this record has rep clauses, force the position to zero. */
2805 if (Present (Parent_Subtype (gnat_entity)))
2807 Entity_Id gnat_parent = Parent_Subtype (gnat_entity);
2810 /* A major complexity here is that the parent subtype will
2811 reference our discriminants in its Discriminant_Constraint
2812 list. But those must reference the parent component of this
2813 record which is of the parent subtype we have not built yet!
2814 To break the circle we first build a dummy COMPONENT_REF which
2815 represents the "get to the parent" operation and initialize
2816 each of those discriminants to a COMPONENT_REF of the above
2817 dummy parent referencing the corresponding discriminant of the
2818 base type of the parent subtype. */
2819 gnu_get_parent = build3 (COMPONENT_REF, void_type_node,
2820 build0 (PLACEHOLDER_EXPR, gnu_type),
2821 build_decl (FIELD_DECL, NULL_TREE,
2825 if (Has_Discriminants (gnat_entity))
2826 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2827 Present (gnat_field);
2828 gnat_field = Next_Stored_Discriminant (gnat_field))
2829 if (Present (Corresponding_Discriminant (gnat_field)))
2832 build3 (COMPONENT_REF,
2833 get_unpadded_type (Etype (gnat_field)),
2835 gnat_to_gnu_field_decl (Corresponding_Discriminant
2840 /* Then we build the parent subtype. If it has discriminants but
2841 the type itself has unknown discriminants, this means that it
2842 doesn't contain information about how the discriminants are
2843 derived from those of the ancestor type, so it cannot be used
2844 directly. Instead it is built by cloning the parent subtype
2845 of the underlying record view of the type, for which the above
2846 derivation of discriminants has been made explicit. */
2847 if (Has_Discriminants (gnat_parent)
2848 && Has_Unknown_Discriminants (gnat_entity))
2850 Entity_Id gnat_uview = Underlying_Record_View (gnat_entity);
2852 /* If we are defining the type, the underlying record
2853 view must already have been elaborated at this point.
2854 Otherwise do it now as its parent subtype cannot be
2855 technically elaborated on its own. */
2857 gcc_assert (present_gnu_tree (gnat_uview));
2859 gnat_to_gnu_entity (gnat_uview, NULL_TREE, 0);
2861 gnu_parent = gnat_to_gnu_type (Parent_Subtype (gnat_uview));
2863 /* Substitute the "get to the parent" of the type for that
2864 of its underlying record view in the cloned type. */
2865 for (gnat_field = First_Stored_Discriminant (gnat_uview);
2866 Present (gnat_field);
2867 gnat_field = Next_Stored_Discriminant (gnat_field))
2868 if (Present (Corresponding_Discriminant (gnat_field)))
2870 tree gnu_field = gnat_to_gnu_field_decl (gnat_field);
2872 = build3 (COMPONENT_REF, TREE_TYPE (gnu_field),
2873 gnu_get_parent, gnu_field, NULL_TREE);
2875 = substitute_in_type (gnu_parent, gnu_field, gnu_ref);
2879 gnu_parent = gnat_to_gnu_type (gnat_parent);
2881 /* Finally we fix up both kinds of twisted COMPONENT_REF we have
2882 initially built. The discriminants must reference the fields
2883 of the parent subtype and not those of its base type for the
2884 placeholder machinery to properly work. */
2885 if (Has_Discriminants (gnat_entity))
2886 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2887 Present (gnat_field);
2888 gnat_field = Next_Stored_Discriminant (gnat_field))
2889 if (Present (Corresponding_Discriminant (gnat_field)))
2891 Entity_Id field = Empty;
2892 for (field = First_Stored_Discriminant (gnat_parent);
2894 field = Next_Stored_Discriminant (field))
2895 if (same_discriminant_p (gnat_field, field))
2897 gcc_assert (Present (field));
2898 TREE_OPERAND (get_gnu_tree (gnat_field), 1)
2899 = gnat_to_gnu_field_decl (field);
2902 /* The "get to the parent" COMPONENT_REF must be given its
2904 TREE_TYPE (gnu_get_parent) = gnu_parent;
2906 /* ...and reference the _parent field of this record. */
2908 = create_field_decl (get_identifier
2909 (Get_Name_String (Name_uParent)),
2910 gnu_parent, gnu_type, 0,
2911 has_rep ? TYPE_SIZE (gnu_parent) : 0,
2912 has_rep ? bitsize_zero_node : 0, 1);
2913 DECL_INTERNAL_P (gnu_field_list) = 1;
2914 TREE_OPERAND (gnu_get_parent, 1) = gnu_field_list;
2917 /* Make the fields for the discriminants and put them into the record
2918 unless it's an Unchecked_Union. */
2919 if (Has_Discriminants (gnat_entity))
2920 for (gnat_field = First_Stored_Discriminant (gnat_entity);
2921 Present (gnat_field);
2922 gnat_field = Next_Stored_Discriminant (gnat_field))
2924 /* If this is a record extension and this discriminant
2925 is the renaming of another discriminant, we've already
2926 handled the discriminant above. */
2927 if (Present (Parent_Subtype (gnat_entity))
2928 && Present (Corresponding_Discriminant (gnat_field)))
2932 = gnat_to_gnu_field (gnat_field, gnu_type, packed, definition);
2934 /* Make an expression using a PLACEHOLDER_EXPR from the
2935 FIELD_DECL node just created and link that with the
2936 corresponding GNAT defining identifier. Then add to the
2938 save_gnu_tree (gnat_field,
2939 build3 (COMPONENT_REF, TREE_TYPE (gnu_field),
2940 build0 (PLACEHOLDER_EXPR,
2941 DECL_CONTEXT (gnu_field)),
2942 gnu_field, NULL_TREE),
2945 if (!Is_Unchecked_Union (gnat_entity))
2947 TREE_CHAIN (gnu_field) = gnu_field_list;
2948 gnu_field_list = gnu_field;
2952 /* Put the discriminants into the record (backwards), so we can
2953 know the appropriate discriminant to use for the names of the
2955 TYPE_FIELDS (gnu_type) = gnu_field_list;
2957 /* Add the listed fields into the record and finish it up. */
2958 components_to_record (gnu_type, Component_List (record_definition),
2959 gnu_field_list, packed, definition, NULL,
2960 false, all_rep, false,
2961 Is_Unchecked_Union (gnat_entity));
2963 /* We used to remove the associations of the discriminants and
2964 _Parent for validity checking, but we may need them if there's
2965 Freeze_Node for a subtype used in this record. */
2966 TYPE_VOLATILE (gnu_type) = Treat_As_Volatile (gnat_entity);
2967 TYPE_BY_REFERENCE_P (gnu_type) = Is_By_Reference_Type (gnat_entity);
2969 /* If it is a tagged record force the type to BLKmode to insure
2970 that these objects will always be placed in memory. Do the
2971 same thing for limited record types. */
2972 if (Is_Tagged_Type (gnat_entity) || Is_Limited_Record (gnat_entity))
2973 SET_TYPE_MODE (gnu_type, BLKmode);
2975 /* Fill in locations of fields. */
2976 annotate_rep (gnat_entity, gnu_type);
2978 /* If there are any entities in the chain corresponding to
2979 components that we did not elaborate, ensure we elaborate their
2980 types if they are Itypes. */
2981 for (gnat_temp = First_Entity (gnat_entity);
2982 Present (gnat_temp); gnat_temp = Next_Entity (gnat_temp))
2983 if ((Ekind (gnat_temp) == E_Component
2984 || Ekind (gnat_temp) == E_Discriminant)
2985 && Is_Itype (Etype (gnat_temp))
2986 && !present_gnu_tree (gnat_temp))
2987 gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0);
2991 case E_Class_Wide_Subtype:
2992 /* If an equivalent type is present, that is what we should use.
2993 Otherwise, fall through to handle this like a record subtype
2994 since it may have constraints. */
2995 if (gnat_equiv_type != gnat_entity)
2997 gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0);
2998 maybe_present = true;
3002 /* ... fall through ... */
3004 case E_Record_Subtype:
3006 /* If Cloned_Subtype is Present it means this record subtype has
3007 identical layout to that type or subtype and we should use
3008 that GCC type for this one. The front end guarantees that
3009 the component list is shared. */
3010 if (Present (Cloned_Subtype (gnat_entity)))
3012 gnu_decl = gnat_to_gnu_entity (Cloned_Subtype (gnat_entity),
3014 maybe_present = true;
3017 /* Otherwise, first ensure the base type is elaborated. Then, if we are
3018 changing the type, make a new type with each field having the
3019 type of the field in the new subtype but having the position
3020 computed by transforming every discriminant reference according
3021 to the constraints. We don't see any difference between
3022 private and nonprivate type here since derivations from types should
3023 have been deferred until the completion of the private type. */
3026 Entity_Id gnat_base_type = Implementation_Base_Type (gnat_entity);
3031 defer_incomplete_level++, this_deferred = true;
3033 /* Get the base type initially for its alignment and sizes. But
3034 if it is a padded type, we do all the other work with the
3036 gnu_base_type = gnat_to_gnu_type (gnat_base_type);
3038 if (TREE_CODE (gnu_base_type) == RECORD_TYPE
3039 && TYPE_IS_PADDING_P (gnu_base_type))
3040 gnu_type = gnu_orig_type = TREE_TYPE (TYPE_FIELDS (gnu_base_type));
3042 gnu_type = gnu_orig_type = gnu_base_type;
3044 if (present_gnu_tree (gnat_entity))
3046 maybe_present = true;
3050 /* When the type has discriminants, and these discriminants
3051 affect the shape of what it built, factor them in.
3053 If we are making a subtype of an Unchecked_Union (must be an
3054 Itype), just return the type.
3056 We can't just use Is_Constrained because private subtypes without
3057 discriminants of full types with discriminants with default
3058 expressions are Is_Constrained but aren't constrained! */
3060 if (IN (Ekind (gnat_base_type), Record_Kind)
3061 && !Is_For_Access_Subtype (gnat_entity)
3062 && !Is_Unchecked_Union (gnat_base_type)
3063 && Is_Constrained (gnat_entity)
3064 && Stored_Constraint (gnat_entity) != No_Elist
3065 && Present (Discriminant_Constraint (gnat_entity)))
3067 Entity_Id gnat_field;
3068 tree gnu_field_list = 0;
3070 = compute_field_positions (gnu_orig_type, NULL_TREE,
3071 size_zero_node, bitsize_zero_node,
3074 = substitution_list (gnat_entity, gnat_base_type, NULL_TREE,
3078 gnu_type = make_node (RECORD_TYPE);
3079 TYPE_NAME (gnu_type) = gnu_entity_name;
3080 TYPE_VOLATILE (gnu_type) = Treat_As_Volatile (gnat_entity);
3082 /* Set the size, alignment and alias set of the new type to
3083 match that of the old one, doing required substitutions.
3084 We do it this early because we need the size of the new
3085 type below to discard old fields if necessary. */
3086 TYPE_SIZE (gnu_type) = TYPE_SIZE (gnu_base_type);
3087 TYPE_SIZE_UNIT (gnu_type) = TYPE_SIZE_UNIT (gnu_base_type);
3088 SET_TYPE_ADA_SIZE (gnu_type, TYPE_ADA_SIZE (gnu_base_type));
3089 TYPE_ALIGN (gnu_type) = TYPE_ALIGN (gnu_base_type);
3090 relate_alias_sets (gnu_type, gnu_base_type, ALIAS_SET_COPY);
3092 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
3093 for (gnu_temp = gnu_subst_list;
3094 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3095 TYPE_SIZE (gnu_type)
3096 = substitute_in_expr (TYPE_SIZE (gnu_type),
3097 TREE_PURPOSE (gnu_temp),
3098 TREE_VALUE (gnu_temp));
3100 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE_UNIT (gnu_type)))
3101 for (gnu_temp = gnu_subst_list;
3102 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3103 TYPE_SIZE_UNIT (gnu_type)
3104 = substitute_in_expr (TYPE_SIZE_UNIT (gnu_type),
3105 TREE_PURPOSE (gnu_temp),
3106 TREE_VALUE (gnu_temp));
3108 if (CONTAINS_PLACEHOLDER_P (TYPE_ADA_SIZE (gnu_type)))
3109 for (gnu_temp = gnu_subst_list;
3110 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3112 (gnu_type, substitute_in_expr (TYPE_ADA_SIZE (gnu_type),
3113 TREE_PURPOSE (gnu_temp),
3114 TREE_VALUE (gnu_temp)));
3116 for (gnat_field = First_Entity (gnat_entity);
3117 Present (gnat_field); gnat_field = Next_Entity (gnat_field))
3118 if ((Ekind (gnat_field) == E_Component
3119 || Ekind (gnat_field) == E_Discriminant)
3120 && (Underlying_Type (Scope (Original_Record_Component
3123 && (No (Corresponding_Discriminant (gnat_field))
3124 || !Is_Tagged_Type (gnat_base_type)))
3127 = gnat_to_gnu_field_decl
3128 (Original_Record_Component (gnat_field));
3131 (purpose_member (gnu_old_field, gnu_pos_list));
3132 tree gnu_pos = TREE_PURPOSE (gnu_offset);
3133 tree gnu_bitpos = TREE_VALUE (TREE_VALUE (gnu_offset));
3134 tree gnu_field, gnu_field_type, gnu_size, gnu_new_pos;
3135 unsigned int offset_align
3137 (TREE_PURPOSE (TREE_VALUE (gnu_offset)), 1);
3139 /* If the type is the same, retrieve the GCC type from the
3140 old field to take into account possible adjustments. */
3141 if (Etype (gnat_field)
3142 == Etype (Original_Record_Component (gnat_field)))
3143 gnu_field_type = TREE_TYPE (gnu_old_field);
3145 gnu_field_type = gnat_to_gnu_type (Etype (gnat_field));
3147 gnu_size = TYPE_SIZE (gnu_field_type);
3149 /* If there was a component clause, the field types must be
3150 the same for the type and subtype, so copy the data from
3151 the old field to avoid recomputation here. Also if the
3152 field is justified modular and the optimization in
3153 gnat_to_gnu_field was applied. */
3154 if (Present (Component_Clause
3155 (Original_Record_Component (gnat_field)))
3156 || (TREE_CODE (gnu_field_type) == RECORD_TYPE
3157 && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type)
3158 && TREE_TYPE (TYPE_FIELDS (gnu_field_type))
3159 == TREE_TYPE (gnu_old_field)))
3161 gnu_size = DECL_SIZE (gnu_old_field);
3162 gnu_field_type = TREE_TYPE (gnu_old_field);
3165 /* If the old field was packed and of constant size, we
3166 have to get the old size here, as it might differ from
3167 what the Etype conveys and the latter might overlap
3168 onto the following field. Try to arrange the type for
3169 possible better packing along the way. */
3170 else if (DECL_PACKED (gnu_old_field)
3171 && TREE_CODE (DECL_SIZE (gnu_old_field))
3174 gnu_size = DECL_SIZE (gnu_old_field);
3175 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
3176 && !TYPE_IS_FAT_POINTER_P (gnu_field_type)
3177 && host_integerp (TYPE_SIZE (gnu_field_type), 1))
3179 = make_packable_type (gnu_field_type, true);
3182 if (CONTAINS_PLACEHOLDER_P (gnu_pos))
3183 for (gnu_temp = gnu_subst_list;
3184 gnu_temp; gnu_temp = TREE_CHAIN (gnu_temp))
3185 gnu_pos = substitute_in_expr (gnu_pos,
3186 TREE_PURPOSE (gnu_temp),
3187 TREE_VALUE (gnu_temp));
3189 /* If the position is now a constant, we can set it as the
3190 position of the field when we make it. Otherwise, we need
3191 to deal with it specially below. */
3192 if (TREE_CONSTANT (gnu_pos))
3194 gnu_new_pos = bit_from_pos (gnu_pos, gnu_bitpos);
3196 /* Discard old fields that are outside the new type.
3197 This avoids confusing code scanning it to decide
3198 how to pass it to functions on some platforms. */
3199 if (TREE_CODE (gnu_new_pos) == INTEGER_CST
3200 && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST
3201 && !integer_zerop (gnu_size)
3202 && !tree_int_cst_lt (gnu_new_pos,
3203 TYPE_SIZE (gnu_type)))
3207 gnu_new_pos = NULL_TREE;
3211 (DECL_NAME (gnu_old_field), gnu_field_type, gnu_type,
3212 DECL_PACKED (gnu_old_field), gnu_size, gnu_new_pos,
3213 !DECL_NONADDRESSABLE_P (gnu_old_field));
3215 if (!TREE_CONSTANT (gnu_pos))
3217 normalize_offset (&gnu_pos, &gnu_bitpos, offset_align);
3218 DECL_FIELD_OFFSET (gnu_field) = gnu_pos;
3219 DECL_FIELD_BIT_OFFSET (gnu_field) = gnu_bitpos;
3220 SET_DECL_OFFSET_ALIGN (gnu_field, offset_align);
3221 DECL_SIZE (gnu_field) = gnu_size;
3222 DECL_SIZE_UNIT (gnu_field)
3223 = convert (sizetype,
3224 size_binop (CEIL_DIV_EXPR, gnu_size,
3225 bitsize_unit_node));
3226 layout_decl (gnu_field, DECL_OFFSET_ALIGN (gnu_field));
3229 DECL_INTERNAL_P (gnu_field)
3230 = DECL_INTERNAL_P (gnu_old_field);
3231 SET_DECL_ORIGINAL_FIELD
3232 (gnu_field, (DECL_ORIGINAL_FIELD (gnu_old_field)
3233 ? DECL_ORIGINAL_FIELD (gnu_old_field)
3235 DECL_DISCRIMINANT_NUMBER (gnu_field)
3236 = DECL_DISCRIMINANT_NUMBER (gnu_old_field);
3237 TREE_THIS_VOLATILE (gnu_field)
3238 = TREE_THIS_VOLATILE (gnu_old_field);
3240 /* To match the layout crafted in components_to_record, if
3241 this is the _Tag field, put it before any discriminants
3242 instead of after them as for all other fields. */
3243 if (Chars (gnat_field) == Name_uTag)
3244 gnu_field_list = chainon (gnu_field_list, gnu_field);
3247 TREE_CHAIN (gnu_field) = gnu_field_list;
3248 gnu_field_list = gnu_field;
3251 save_gnu_tree (gnat_field, gnu_field, false);
3254 /* Now go through the entities again looking for Itypes that
3255 we have not elaborated but should (e.g., Etypes of fields
3256 that have Original_Components). */
3257 for (gnat_field = First_Entity (gnat_entity);
3258 Present (gnat_field); gnat_field = Next_Entity (gnat_field))
3259 if ((Ekind (gnat_field) == E_Discriminant
3260 || Ekind (gnat_field) == E_Component)
3261 && !present_gnu_tree (Etype (gnat_field)))
3262 gnat_to_gnu_entity (Etype (gnat_field), NULL_TREE, 0);
3264 /* Do not finalize it since we're going to modify it below. */
3265 gnu_field_list = nreverse (gnu_field_list);
3266 finish_record_type (gnu_type, gnu_field_list, 2, true);
3268 /* Finalize size and mode. */
3269 TYPE_SIZE (gnu_type) = variable_size (TYPE_SIZE (gnu_type));
3270 TYPE_SIZE_UNIT (gnu_type)
3271 = variable_size (TYPE_SIZE_UNIT (gnu_type));
3273 compute_record_mode (gnu_type);
3275 /* Fill in locations of fields. */
3276 annotate_rep (gnat_entity, gnu_type);
3278 /* We've built a new type, make an XVS type to show what this
3279 is a subtype of. Some debuggers require the XVS type to be
3280 output first, so do it in that order. */
3283 tree gnu_subtype_marker = make_node (RECORD_TYPE);
3284 tree gnu_orig_name = TYPE_NAME (gnu_orig_type);
3286 if (TREE_CODE (gnu_orig_name) == TYPE_DECL)
3287 gnu_orig_name = DECL_NAME (gnu_orig_name);
3289 TYPE_NAME (gnu_subtype_marker)
3290 = create_concat_name (gnat_entity, "XVS");
3291 finish_record_type (gnu_subtype_marker,
3292 create_field_decl (gnu_orig_name,
3299 add_parallel_type (TYPE_STUB_DECL (gnu_type),
3300 gnu_subtype_marker);
3303 /* Now we can finalize it. */
3304 rest_of_record_type_compilation (gnu_type);
3307 /* Otherwise, go down all the components in the new type and
3308 make them equivalent to those in the base type. */
3310 for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp);
3311 gnat_temp = Next_Entity (gnat_temp))
3312 if ((Ekind (gnat_temp) == E_Discriminant
3313 && !Is_Unchecked_Union (gnat_base_type))
3314 || Ekind (gnat_temp) == E_Component)
3315 save_gnu_tree (gnat_temp,
3316 gnat_to_gnu_field_decl
3317 (Original_Record_Component (gnat_temp)), false);
3321 case E_Access_Subprogram_Type:
3322 /* Use the special descriptor type for dispatch tables if needed,
3323 that is to say for the Prim_Ptr of a-tags.ads and its clones.
3324 Note that we are only required to do so for static tables in
3325 order to be compatible with the C++ ABI, but Ada 2005 allows
3326 to extend library level tagged types at the local level so
3327 we do it in the non-static case as well. */
3328 if (TARGET_VTABLE_USES_DESCRIPTORS
3329 && Is_Dispatch_Table_Entity (gnat_entity))
3331 gnu_type = fdesc_type_node;
3332 gnu_size = TYPE_SIZE (gnu_type);
3336 /* ... fall through ... */
3338 case E_Anonymous_Access_Subprogram_Type:
3339 /* If we are not defining this entity, and we have incomplete
3340 entities being processed above us, make a dummy type and
3341 fill it in later. */
3342 if (!definition && defer_incomplete_level != 0)
3344 struct incomplete *p
3345 = (struct incomplete *) xmalloc (sizeof (struct incomplete));
3348 = build_pointer_type
3349 (make_dummy_type (Directly_Designated_Type (gnat_entity)));
3350 gnu_decl = create_type_decl (gnu_entity_name, gnu_type, attr_list,
3351 !Comes_From_Source (gnat_entity),
3352 debug_info_p, gnat_entity);
3353 this_made_decl = true;
3354 gnu_type = TREE_TYPE (gnu_decl);
3355 save_gnu_tree (gnat_entity, gnu_decl, false);
3358 p->old_type = TREE_TYPE (gnu_type);
3359 p->full_type = Directly_Designated_Type (gnat_entity);
3360 p->next = defer_incomplete_list;
3361 defer_incomplete_list = p;
3365 /* ... fall through ... */
3367 case E_Allocator_Type:
3369 case E_Access_Attribute_Type:
3370 case E_Anonymous_Access_Type:
3371 case E_General_Access_Type:
3373 Entity_Id gnat_desig_type = Directly_Designated_Type (gnat_entity);
3374 Entity_Id gnat_desig_equiv = Gigi_Equivalent_Type (gnat_desig_type);
3375 bool is_from_limited_with
3376 = (IN (Ekind (gnat_desig_equiv), Incomplete_Kind)
3377 && From_With_Type (gnat_desig_equiv));
3379 /* Get the "full view" of this entity. If this is an incomplete
3380 entity from a limited with, treat its non-limited view as the full
3381 view. Otherwise, if this is an incomplete or private type, use the
3382 full view. In the former case, we might point to a private type,
3383 in which case, we need its full view. Also, we want to look at the
3384 actual type used for the representation, so this takes a total of
3386 Entity_Id gnat_desig_full_direct_first
3387 = (is_from_limited_with ? Non_Limited_View (gnat_desig_equiv)
3388 : (IN (Ekind (gnat_desig_equiv), Incomplete_Or_Private_Kind)
3389 ? Full_View (gnat_desig_equiv) : Empty));
3390 Entity_Id gnat_desig_full_direct
3391 = ((is_from_limited_with
3392 && Present (gnat_desig_full_direct_first)
3393 && IN (Ekind (gnat_desig_full_direct_first), Private_Kind))
3394 ? Full_View (gnat_desig_full_direct_first)
3395 : gnat_desig_full_direct_first);
3396 Entity_Id gnat_desig_full
3397 = Gigi_Equivalent_Type (gnat_desig_full_direct);
3399 /* This the type actually used to represent the designated type,
3400 either gnat_desig_full or gnat_desig_equiv. */
3401 Entity_Id gnat_desig_rep;
3403 /* True if this is a pointer to an unconstrained array. */
3404 bool is_unconstrained_array;
3406 /* We want to know if we'll be seeing the freeze node for any
3407 incomplete type we may be pointing to. */
3409 = (Present (gnat_desig_full)
3410 ? In_Extended_Main_Code_Unit (gnat_desig_full)
3411 : In_Extended_Main_Code_Unit (gnat_desig_type));
3413 /* True if we make a dummy type here. */
3414 bool got_fat_p = false;
3415 /* True if the dummy is a fat pointer. */
3416 bool made_dummy = false;
3417 tree gnu_desig_type = NULL_TREE;
3418 enum machine_mode p_mode = mode_for_size (esize, MODE_INT, 0);
3420 if (!targetm.valid_pointer_mode (p_mode))
3423 /* If either the designated type or its full view is an unconstrained
3424 array subtype, replace it with the type it's a subtype of. This
3425 avoids problems with multiple copies of unconstrained array types.
3426 Likewise, if the designated type is a subtype of an incomplete
3427 record type, use the parent type to avoid order of elaboration
3428 issues. This can lose some code efficiency, but there is no
3430 if (Ekind (gnat_desig_equiv) == E_Array_Subtype
3431 && ! Is_Constrained (gnat_desig_equiv))
3432 gnat_desig_equiv = Etype (gnat_desig_equiv);
3433 if (Present (gnat_desig_full)
3434 && ((Ekind (gnat_desig_full) == E_Array_Subtype
3435 && ! Is_Constrained (gnat_desig_full))
3436 || (Ekind (gnat_desig_full) == E_Record_Subtype
3437 && Ekind (Etype (gnat_desig_full)) == E_Record_Type)))
3438 gnat_desig_full = Etype (gnat_desig_full);
3440 /* Now set the type that actually marks the representation of
3441 the designated type and also flag whether we have a unconstrained
3443 gnat_desig_rep = gnat_desig_full ? gnat_desig_full : gnat_desig_equiv;
3444 is_unconstrained_array
3445 = (Is_Array_Type (gnat_desig_rep)
3446 && ! Is_Constrained (gnat_desig_rep));
3448 /* If we are pointing to an incomplete type whose completion is an
3449 unconstrained array, make a fat pointer type. The two types in our
3450 fields will be pointers to dummy nodes and will be replaced in
3451 update_pointer_to. Similarly, if the type itself is a dummy type or
3452 an unconstrained array. Also make a dummy TYPE_OBJECT_RECORD_TYPE
3453 in case we have any thin pointers to it. */
3454 if (is_unconstrained_array
3455 && (Present (gnat_desig_full)
3456 || (present_gnu_tree (gnat_desig_equiv)
3457 && TYPE_IS_DUMMY_P (TREE_TYPE
3458 (get_gnu_tree (gnat_desig_equiv))))
3459 || (No (gnat_desig_full) && ! in_main_unit
3460 && defer_incomplete_level != 0
3461 && ! present_gnu_tree (gnat_desig_equiv))
3462 || (in_main_unit && is_from_limited_with
3463 && Present (Freeze_Node (gnat_desig_rep)))))
3467 if (present_gnu_tree (gnat_desig_rep))
3468 gnu_old = TREE_TYPE (get_gnu_tree (gnat_desig_rep));
3471 gnu_old = make_dummy_type (gnat_desig_rep);
3473 /* Show the dummy we get will be a fat pointer. */
3474 got_fat_p = made_dummy = true;
3477 /* If the call above got something that has a pointer, that
3478 pointer is our type. This could have happened either
3479 because the type was elaborated or because somebody
3480 else executed the code below. */
3481 gnu_type = TYPE_POINTER_TO (gnu_old);
3484 tree gnu_template_type = make_node (ENUMERAL_TYPE);
3485 tree gnu_ptr_template = build_pointer_type (gnu_template_type);
3486 tree gnu_array_type = make_node (ENUMERAL_TYPE);
3487 tree gnu_ptr_array = build_pointer_type (gnu_array_type);
3490 TYPE_NAME (gnu_template_type)
3491 = create_concat_name (gnat_desig_equiv, "XUB");
3492 TYPE_DUMMY_P (gnu_template_type) = 1;
3494 TYPE_NAME (gnu_array_type)
3495 = create_concat_name (gnat_desig_equiv, "XUA");
3496 TYPE_DUMMY_P (gnu_array_type) = 1;
3498 gnu_type = make_node (RECORD_TYPE);
3499 SET_TYPE_UNCONSTRAINED_ARRAY (gnu_type, gnu_old);
3500 TYPE_POINTER_TO (gnu_old) = gnu_type;
3502 Sloc_to_locus (Sloc (gnat_entity), &input_location);
3504 = chainon (chainon (NULL_TREE,
3506 (get_identifier ("P_ARRAY"),
3508 gnu_type, 0, 0, 0, 0)),
3509 create_field_decl (get_identifier ("P_BOUNDS"),
3511 gnu_type, 0, 0, 0, 0));
3513 /* Make sure we can place this into a register. */
3514 TYPE_ALIGN (gnu_type)
3515 = MIN (BIGGEST_ALIGNMENT, 2 * POINTER_SIZE);
3516 TYPE_IS_FAT_POINTER_P (gnu_type) = 1;
3518 /* Do not finalize this record type since the types of
3519 its fields are incomplete. */
3520 finish_record_type (gnu_type, fields, 0, true);
3522 TYPE_OBJECT_RECORD_TYPE (gnu_old) = make_node (RECORD_TYPE);
3523 TYPE_NAME (TYPE_OBJECT_RECORD_TYPE (gnu_old))
3524 = create_concat_name (gnat_desig_equiv, "XUT");
3525 TYPE_DUMMY_P (TYPE_OBJECT_RECORD_TYPE (gnu_old)) = 1;
3529 /* If we already know what the full type is, use it. */
3530 else if (Present (gnat_desig_full)
3531 && present_gnu_tree (gnat_desig_full))
3532 gnu_desig_type = TREE_TYPE (get_gnu_tree (gnat_desig_full));
3534 /* Get the type of the thing we are to point to and build a pointer
3535 to it. If it is a reference to an incomplete or private type with a
3536 full view that is a record, make a dummy type node and get the
3537 actual type later when we have verified it is safe. */
3538 else if ((! in_main_unit
3539 && ! present_gnu_tree (gnat_desig_equiv)
3540 && Present (gnat_desig_full)
3541 && ! present_gnu_tree (gnat_desig_full)
3542 && Is_Record_Type (gnat_desig_full))
3543 /* Likewise if we are pointing to a record or array and we
3544 are to defer elaborating incomplete types. We do this
3545 since this access type may be the full view of some
3546 private type. Note that the unconstrained array case is
3548 || ((! in_main_unit || imported_p)
3549 && defer_incomplete_level != 0
3550 && ! present_gnu_tree (gnat_desig_equiv)
3551 && ((Is_Record_Type (gnat_desig_rep)
3552 || Is_Array_Type (gnat_desig_rep))))
3553 /* If this is a reference from a limited_with type back to our
3554 main unit and there's a Freeze_Node for it, either we have
3555 already processed the declaration and made the dummy type,
3556 in which case we just reuse the latter, or we have not yet,
3557 in which case we make the dummy type and it will be reused
3558 when the declaration is processed. In both cases, the
3559 pointer eventually created below will be automatically
3560 adjusted when the Freeze_Node is processed. Note that the
3561 unconstrained array case is handled above. */
3562 || (in_main_unit && is_from_limited_with
3563 && Present (Freeze_Node (gnat_desig_rep))))
3565 gnu_desig_type = make_dummy_type (gnat_desig_equiv);
3569 /* Otherwise handle the case of a pointer to itself. */
3570 else if (gnat_desig_equiv == gnat_entity)
3573 = build_pointer_type_for_mode (void_type_node, p_mode,
3574 No_Strict_Aliasing (gnat_entity));
3575 TREE_TYPE (gnu_type) = TYPE_POINTER_TO (gnu_type) = gnu_type;
3578 /* If expansion is disabled, the equivalent type of a concurrent
3579 type is absent, so build a dummy pointer type. */
3580 else if (type_annotate_only && No (gnat_desig_equiv))
3581 gnu_type = ptr_void_type_node;
3583 /* Finally, handle the straightforward case where we can just
3584 elaborate our designated type and point to it. */
3586 gnu_desig_type = gnat_to_gnu_type (gnat_desig_equiv);
3588 /* It is possible that a call to gnat_to_gnu_type above resolved our
3589 type. If so, just return it. */
3590 if (present_gnu_tree (gnat_entity))
3592 maybe_present = true;
3596 /* If we have a GCC type for the designated type, possibly modify it
3597 if we are pointing only to constant objects and then make a pointer
3598 to it. Don't do this for unconstrained arrays. */
3599 if (!gnu_type && gnu_desig_type)
3601 if (Is_Access_Constant (gnat_entity)
3602 && TREE_CODE (gnu_desig_type) != UNCONSTRAINED_ARRAY_TYPE)
3605 = build_qualified_type
3607 TYPE_QUALS (gnu_desig_type) | TYPE_QUAL_CONST);
3609 /* Some extra processing is required if we are building a
3610 pointer to an incomplete type (in the GCC sense). We might
3611 have such a type if we just made a dummy, or directly out
3612 of the call to gnat_to_gnu_type above if we are processing
3613 an access type for a record component designating the
3614 record type itself. */
3615 if (TYPE_MODE (gnu_desig_type) == VOIDmode)
3617 /* We must ensure that the pointer to variant we make will
3618 be processed by update_pointer_to when the initial type
3619 is completed. Pretend we made a dummy and let further
3620 processing act as usual. */
3623 /* We must ensure that update_pointer_to will not retrieve
3624 the dummy variant when building a properly qualified
3625 version of the complete type. We take advantage of the
3626 fact that get_qualified_type is requiring TYPE_NAMEs to
3627 match to influence build_qualified_type and then also
3628 update_pointer_to here. */
3629 TYPE_NAME (gnu_desig_type)
3630 = create_concat_name (gnat_desig_type, "INCOMPLETE_CST");
3635 = build_pointer_type_for_mode (gnu_desig_type, p_mode,
3636 No_Strict_Aliasing (gnat_entity));
3639 /* If we are not defining this object and we made a dummy pointer,
3640 save our current definition, evaluate the actual type, and replace
3641 the tentative type we made with the actual one. If we are to defer
3642 actually looking up the actual type, make an entry in the
3643 deferred list. If this is from a limited with, we have to defer
3644 to the end of the current spec in two cases: first if the
3645 designated type is in the current unit and second if the access
3647 if ((! in_main_unit || is_from_limited_with) && made_dummy)
3650 = TYPE_FAT_POINTER_P (gnu_type)
3651 ? TYPE_UNCONSTRAINED_ARRAY (gnu_type) : TREE_TYPE (gnu_type);
3653 if (esize == POINTER_SIZE
3654 && (got_fat_p || TYPE_FAT_POINTER_P (gnu_type)))
3656 = build_pointer_type
3657 (TYPE_OBJECT_RECORD_TYPE
3658 (TYPE_UNCONSTRAINED_ARRAY (gnu_type)));
3660 gnu_decl = create_type_decl (gnu_entity_name, gnu_type, attr_list,
3661 !Comes_From_Source (gnat_entity),
3662 debug_info_p, gnat_entity);
3663 this_made_decl = true;
3664 gnu_type = TREE_TYPE (gnu_decl);
3665 save_gnu_tree (gnat_entity, gnu_decl, false);
3668 if (defer_incomplete_level == 0
3669 && ! (is_from_limited_with
3671 || In_Extended_Main_Code_Unit (gnat_entity))))
3672 update_pointer_to (TYPE_MAIN_VARIANT (gnu_old_type),
3673 gnat_to_gnu_type (gnat_desig_equiv));
3675 /* Note that the call to gnat_to_gnu_type here might have
3676 updated gnu_old_type directly, in which case it is not a
3677 dummy type any more when we get into update_pointer_to.
3679 This may happen for instance when the designated type is a
3680 record type, because their elaboration starts with an
3681 initial node from make_dummy_type, which may yield the same
3682 node as the one we got.
3684 Besides, variants of this non-dummy type might have been
3685 created along the way. update_pointer_to is expected to
3686 properly take care of those situations. */
3689 struct incomplete *p
3690 = (struct incomplete *) xmalloc (sizeof
3691 (struct incomplete));
3692 struct incomplete **head
3693 = (is_from_limited_with
3695 || In_Extended_Main_Code_Unit (gnat_entity))
3696 ? &defer_limited_with : &defer_incomplete_list);
3698 p->old_type = gnu_old_type;
3699 p->full_type = gnat_desig_equiv;
3707 case E_Access_Protected_Subprogram_Type:
3708 case E_Anonymous_Access_Protected_Subprogram_Type:
3709 if (type_annotate_only && No (gnat_equiv_type))
3710 gnu_type = ptr_void_type_node;
3713 /* The runtime representation is the equivalent type. */
3714 gnu_type = gnat_to_gnu_type (gnat_equiv_type);
3715 maybe_present = true;
3718 if (Is_Itype (Directly_Designated_Type (gnat_entity))
3719 && !present_gnu_tree (Directly_Designated_Type (gnat_entity))
3720 && No (Freeze_Node (Directly_Designated_Type (gnat_entity)))
3721 && !Is_Record_Type (Scope (Directly_Designated_Type (gnat_entity))))
3722 gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity),
3727 case E_Access_Subtype:
3729 /* We treat this as identical to its base type; any constraint is
3730 meaningful only to the front end.
3732 The designated type must be elaborated as well, if it does
3733 not have its own freeze node. Designated (sub)types created
3734 for constrained components of records with discriminants are
3735 not frozen by the front end and thus not elaborated by gigi,
3736 because their use may appear before the base type is frozen,
3737 and because it is not clear that they are needed anywhere in
3738 Gigi. With the current model, there is no correct place where
3739 they could be elaborated. */
3741 gnu_type = gnat_to_gnu_type (Etype (gnat_entity));
3742 if (Is_Itype (Directly_Designated_Type (gnat_entity))
3743 && !present_gnu_tree (Directly_Designated_Type (gnat_entity))
3744 && Is_Frozen (Directly_Designated_Type (gnat_entity))
3745 && No (Freeze_Node (Directly_Designated_Type (gnat_entity))))
3747 /* If we are not defining this entity, and we have incomplete
3748 entities being processed above us, make a dummy type and
3749 elaborate it later. */
3750 if (!definition && defer_incomplete_level != 0)
3752 struct incomplete *p
3753 = (struct incomplete *) xmalloc (sizeof (struct incomplete));
3755 = build_pointer_type
3756 (make_dummy_type (Directly_Designated_Type (gnat_entity)));
3758 p->old_type = TREE_TYPE (gnu_ptr_type);
3759 p->full_type = Directly_Designated_Type (gnat_entity);
3760 p->next = defer_incomplete_list;
3761 defer_incomplete_list = p;
3763 else if (!IN (Ekind (Base_Type
3764 (Directly_Designated_Type (gnat_entity))),
3765 Incomplete_Or_Private_Kind))
3766 gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity),
3770 maybe_present = true;
3773 /* Subprogram Entities
3775 The following access functions are defined for subprograms (functions
3778 First_Formal The first formal parameter.
3779 Is_Imported Indicates that the subprogram has appeared in
3780 an INTERFACE or IMPORT pragma. For now we
3781 assume that the external language is C.
3782 Is_Exported Likewise but for an EXPORT pragma.
3783 Is_Inlined True if the subprogram is to be inlined.
3785 In addition for function subprograms we have:
3787 Etype Return type of the function.
3789 Each parameter is first checked by calling must_pass_by_ref on its
3790 type to determine if it is passed by reference. For parameters which
3791 are copied in, if they are Ada In Out or Out parameters, their return
3792 value becomes part of a record which becomes the return type of the
3793 function (C function - note that this applies only to Ada procedures
3794 so there is no Ada return type). Additional code to store back the
3795 parameters will be generated on the caller side. This transformation
3796 is done here, not in the front-end.
3798 The intended result of the transformation can be seen from the
3799 equivalent source rewritings that follow:
3801 struct temp {int a,b};
3802 procedure P (A,B: In Out ...) is temp P (int A,B)
3805 end P; return {A,B};
3812 For subprogram types we need to perform mainly the same conversions to
3813 GCC form that are needed for procedures and function declarations. The
3814 only difference is that at the end, we make a type declaration instead
3815 of a function declaration. */
3817 case E_Subprogram_Type:
3821 /* The first GCC parameter declaration (a PARM_DECL node). The
3822 PARM_DECL nodes are chained through the TREE_CHAIN field, so this
3823 actually is the head of this parameter list. */
3824 tree gnu_param_list = NULL_TREE;
3825 /* Likewise for the stub associated with an exported procedure. */
3826 tree gnu_stub_param_list = NULL_TREE;
3827 /* The type returned by a function. If the subprogram is a procedure
3828 this type should be void_type_node. */
3829 tree gnu_return_type = void_type_node;
3830 /* List of fields in return type of procedure with copy-in copy-out
3832 tree gnu_field_list = NULL_TREE;
3833 /* Non-null for subprograms containing parameters passed by copy-in
3834 copy-out (Ada In Out or Out parameters not passed by reference),
3835 in which case it is the list of nodes used to specify the values of
3836 the in out/out parameters that are returned as a record upon
3837 procedure return. The TREE_PURPOSE of an element of this list is
3838 a field of the record and the TREE_VALUE is the PARM_DECL
3839 corresponding to that field. This list will be saved in the
3840 TYPE_CI_CO_LIST field of the FUNCTION_TYPE node we create. */
3841 tree gnu_return_list = NULL_TREE;
3842 /* If an import pragma asks to map this subprogram to a GCC builtin,
3843 this is the builtin DECL node. */
3844 tree gnu_builtin_decl = NULL_TREE;
3845 /* For the stub associated with an exported procedure. */
3846 tree gnu_stub_type = NULL_TREE, gnu_stub_name = NULL_TREE;
3847 tree gnu_ext_name = create_concat_name (gnat_entity, NULL);
3848 Entity_Id gnat_param;
3849 bool inline_flag = Is_Inlined (gnat_entity);
3850 bool public_flag = Is_Public (gnat_entity) || imported_p;
3852 = (Is_Public (gnat_entity) && !definition) || imported_p;
3854 /* The semantics of "pure" in Ada essentially matches that of "const"
3855 in the back-end. In particular, both properties are orthogonal to
3856 the "nothrow" property if the EH circuitry is explicit in the
3857 internal representation of the back-end. If we are to completely
3858 hide the EH circuitry from it, we need to declare that calls to pure
3859 Ada subprograms that can throw have side effects since they can
3860 trigger an "abnormal" transfer of control flow; thus they can be
3861 neither "const" nor "pure" in the back-end sense. */
3863 = (Exception_Mechanism == Back_End_Exceptions
3864 && Is_Pure (gnat_entity));
3866 bool volatile_flag = No_Return (gnat_entity);
3867 bool returns_by_ref = false;
3868 bool returns_unconstrained = false;
3869 bool returns_by_target_ptr = false;
3870 bool has_copy_in_out = false;
3871 bool has_stub = false;
3874 if (kind == E_Subprogram_Type && !definition)
3875 /* A parameter may refer to this type, so defer completion
3876 of any incomplete types. */
3877 defer_incomplete_level++, this_deferred = true;
3879 /* If the subprogram has an alias, it is probably inherited, so
3880 we can use the original one. If the original "subprogram"
3881 is actually an enumeration literal, it may be the first use
3882 of its type, so we must elaborate that type now. */
3883 if (Present (Alias (gnat_entity)))
3885 if (Ekind (Alias (gnat_entity)) == E_Enumeration_Literal)
3886 gnat_to_gnu_entity (Etype (Alias (gnat_entity)), NULL_TREE, 0);
3888 gnu_decl = gnat_to_gnu_entity (Alias (gnat_entity),
3891 /* Elaborate any Itypes in the parameters of this entity. */
3892 for (gnat_temp = First_Formal_With_Extras (gnat_entity);
3893 Present (gnat_temp);
3894 gnat_temp = Next_Formal_With_Extras (gnat_temp))
3895 if (Is_Itype (Etype (gnat_temp)))
3896 gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0);
3901 /* If this subprogram is expectedly bound to a GCC builtin, fetch the
3902 corresponding DECL node.
3904 We still want the parameter associations to take place because the
3905 proper generation of calls depends on it (a GNAT parameter without
3906 a corresponding GCC tree has a very specific meaning), so we don't
3908 if (Convention (gnat_entity) == Convention_Intrinsic)
3909 gnu_builtin_decl = builtin_decl_for (gnu_ext_name);
3911 /* ??? What if we don't find the builtin node above ? warn ? err ?
3912 In the current state we neither warn nor err, and calls will just
3913 be handled as for regular subprograms. */
3915 if (kind == E_Function || kind == E_Subprogram_Type)
3916 gnu_return_type = gnat_to_gnu_type (Etype (gnat_entity));
3918 /* If this function returns by reference, make the actual
3919 return type of this function the pointer and mark the decl. */
3920 if (Returns_By_Ref (gnat_entity))
3922 returns_by_ref = true;
3923 gnu_return_type = build_pointer_type (gnu_return_type);
3926 /* If the Mechanism is By_Reference, ensure the return type uses
3927 the machine's by-reference mechanism, which may not the same
3928 as above (e.g., it might be by passing a fake parameter). */
3929 else if (kind == E_Function
3930 && Mechanism (gnat_entity) == By_Reference)
3932 TREE_ADDRESSABLE (gnu_return_type) = 1;
3934 /* We expect this bit to be reset by gigi shortly, so can avoid a
3935 type node copy here. This actually also prevents troubles with
3936 the generation of debug information for the function, because
3937 we might have issued such info for this type already, and would
3938 be attaching a distinct type node to the function if we made a
3942 /* If we are supposed to return an unconstrained array,
3943 actually return a fat pointer and make a note of that. Return
3944 a pointer to an unconstrained record of variable size. */
3945 else if (TREE_CODE (gnu_return_type) == UNCONSTRAINED_ARRAY_TYPE)
3947 gnu_return_type = TREE_TYPE (gnu_return_type);
3948 returns_unconstrained = true;
3951 /* If the type requires a transient scope, the result is allocated
3952 on the secondary stack, so the result type of the function is
3954 else if (Requires_Transient_Scope (Etype (gnat_entity)))
3956 gnu_return_type = build_pointer_type (gnu_return_type);
3957 returns_unconstrained = true;
3960 /* If the type is a padded type and the underlying type would not
3961 be passed by reference or this function has a foreign convention,
3962 return the underlying type. */
3963 else if (TREE_CODE (gnu_return_type) == RECORD_TYPE
3964 && TYPE_IS_PADDING_P (gnu_return_type)
3965 && (!default_pass_by_ref (TREE_TYPE
3966 (TYPE_FIELDS (gnu_return_type)))
3967 || Has_Foreign_Convention (gnat_entity)))
3968 gnu_return_type = TREE_TYPE (TYPE_FIELDS (gnu_return_type));
3970 /* If the return type has a non-constant size, we convert the function
3971 into a procedure and its caller will pass a pointer to an object as
3972 the first parameter when we call the function. This can happen for
3973 an unconstrained type with a maximum size or a constrained type with
3974 a size not known at compile time. */
3975 if (TYPE_SIZE_UNIT (gnu_return_type)
3976 && !TREE_CONSTANT (TYPE_SIZE_UNIT (gnu_return_type)))
3978 returns_by_target_ptr = true;
3980 = create_param_decl (get_identifier ("TARGET"),
3981 build_reference_type (gnu_return_type),
3983 gnu_return_type = void_type_node;
3986 /* If the return type has a size that overflows, we cannot have
3987 a function that returns that type. This usage doesn't make
3988 sense anyway, so give an error here. */
3989 if (TYPE_SIZE_UNIT (gnu_return_type)
3990 && TREE_CONSTANT (TYPE_SIZE_UNIT (gnu_return_type))
3991 && TREE_OVERFLOW (TYPE_SIZE_UNIT (gnu_return_type)))
3993 post_error ("cannot return type whose size overflows",
3995 gnu_return_type = copy_node (gnu_return_type);
3996 TYPE_SIZE (gnu_return_type) = bitsize_zero_node;
3997 TYPE_SIZE_UNIT (gnu_return_type) = size_zero_node;
3998 TYPE_MAIN_VARIANT (gnu_return_type) = gnu_return_type;
3999 TYPE_NEXT_VARIANT (gnu_return_type) = NULL_TREE;
4002 /* Look at all our parameters and get the type of
4003 each. While doing this, build a copy-out structure if
4006 /* Loop over the parameters and get their associated GCC tree.
4007 While doing this, build a copy-out structure if we need one. */
4008 for (gnat_param = First_Formal_With_Extras (gnat_entity), parmnum = 0;
4009 Present (gnat_param);
4010 gnat_param = Next_Formal_With_Extras (gnat_param), parmnum++)
4012 tree gnu_param_name = get_entity_name (gnat_param);
4013 tree gnu_param_type = gnat_to_gnu_type (Etype (gnat_param));
4014 tree gnu_param, gnu_field;
4015 bool copy_in_copy_out = false;
4016 Mechanism_Type mech = Mechanism (gnat_param);
4018 /* Builtins are expanded inline and there is no real call sequence
4019 involved. So the type expected by the underlying expander is
4020 always the type of each argument "as is". */
4021 if (gnu_builtin_decl)
4023 /* Handle the first parameter of a valued procedure specially. */
4024 else if (Is_Valued_Procedure (gnat_entity) && parmnum == 0)
4025 mech = By_Copy_Return;
4026 /* Otherwise, see if a Mechanism was supplied that forced this
4027 parameter to be passed one way or another. */
4028 else if (mech == Default
4029 || mech == By_Copy || mech == By_Reference)
4031 else if (By_Descriptor_Last <= mech && mech <= By_Descriptor)
4032 mech = By_Descriptor;
4034 else if (By_Short_Descriptor_Last <= mech &&
4035 mech <= By_Short_Descriptor)
4036 mech = By_Short_Descriptor;
4040 if (TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE
4041 || TREE_CODE (TYPE_SIZE (gnu_param_type)) != INTEGER_CST
4042 || 0 < compare_tree_int (TYPE_SIZE (gnu_param_type),
4044 mech = By_Reference;
4050 post_error ("unsupported mechanism for&", gnat_param);
4055 = gnat_to_gnu_param (gnat_param, mech, gnat_entity,
4056 Has_Foreign_Convention (gnat_entity),
4059 /* We are returned either a PARM_DECL or a type if no parameter
4060 needs to be passed; in either case, adjust the type. */
4061 if (DECL_P (gnu_param))
4062 gnu_param_type = TREE_TYPE (gnu_param);
4065 gnu_param_type = gnu_param;
4066 gnu_param = NULL_TREE;
4071 /* If it's an exported subprogram, we build a parameter list
4072 in parallel, in case we need to emit a stub for it. */
4073 if (Is_Exported (gnat_entity))
4076 = chainon (gnu_param, gnu_stub_param_list);
4077 /* Change By_Descriptor parameter to By_Reference for
4078 the internal version of an exported subprogram. */
4079 if (mech == By_Descriptor || mech == By_Short_Descriptor)
4082 = gnat_to_gnu_param (gnat_param, By_Reference,
4088 gnu_param = copy_node (gnu_param);
4091 gnu_param_list = chainon (gnu_param, gnu_param_list);
4092 Sloc_to_locus (Sloc (gnat_param),
4093 &DECL_SOURCE_LOCATION (gnu_param));
4094 save_gnu_tree (gnat_param, gnu_param, false);
4096 /* If a parameter is a pointer, this function may modify
4097 memory through it and thus shouldn't be considered
4098 a const function. Also, the memory may be modified
4099 between two calls, so they can't be CSE'ed. The latter
4100 case also handles by-ref parameters. */
4101 if (POINTER_TYPE_P (gnu_param_type)
4102 || TYPE_FAT_POINTER_P (gnu_param_type))
4106 if (copy_in_copy_out)
4108 if (!has_copy_in_out)
4110 gcc_assert (TREE_CODE (gnu_return_type) == VOID_TYPE);
4111 gnu_return_type = make_node (RECORD_TYPE);
4112 TYPE_NAME (gnu_return_type) = get_identifier ("RETURN");
4113 has_copy_in_out = true;
4116 gnu_field = create_field_decl (gnu_param_name, gnu_param_type,
4117 gnu_return_type, 0, 0, 0, 0);
4118 Sloc_to_locus (Sloc (gnat_param),
4119 &DECL_SOURCE_LOCATION (gnu_field));
4120 TREE_CHAIN (gnu_field) = gnu_field_list;
4121 gnu_field_list = gnu_field;
4122 gnu_return_list = tree_cons (gnu_field, gnu_param,
4127 /* Do not compute record for out parameters if subprogram is
4128 stubbed since structures are incomplete for the back-end. */
4129 if (gnu_field_list && Convention (gnat_entity) != Convention_Stubbed)
4130 finish_record_type (gnu_return_type, nreverse (gnu_field_list),
4133 /* If we have a CICO list but it has only one entry, we convert
4134 this function into a function that simply returns that one
4136 if (list_length (gnu_return_list) == 1)
4137 gnu_return_type = TREE_TYPE (TREE_PURPOSE (gnu_return_list));
4139 if (Has_Stdcall_Convention (gnat_entity))
4140 prepend_one_attribute_to
4141 (&attr_list, ATTR_MACHINE_ATTRIBUTE,
4142 get_identifier ("stdcall"), NULL_TREE,
4145 /* If we are on a target where stack realignment is needed for 'main'
4146 to honor GCC's implicit expectations (stack alignment greater than
4147 what the base ABI guarantees), ensure we do the same for foreign
4148 convention subprograms as they might be used as callbacks from code
4149 breaking such expectations. Note that this applies to task entry
4150 points in particular. */
4151 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
4152 && Has_Foreign_Convention (gnat_entity))
4153 prepend_one_attribute_to
4154 (&attr_list, ATTR_MACHINE_ATTRIBUTE,
4155 get_identifier ("force_align_arg_pointer"), NULL_TREE,
4158 /* The lists have been built in reverse. */
4159 gnu_param_list = nreverse (gnu_param_list);
4161 gnu_stub_param_list = nreverse (gnu_stub_param_list);
4162 gnu_return_list = nreverse (gnu_return_list);
4164 if (Ekind (gnat_entity) == E_Function)
4165 Set_Mechanism (gnat_entity,
4166 (returns_by_ref || returns_unconstrained
4167 ? By_Reference : By_Copy));
4169 = create_subprog_type (gnu_return_type, gnu_param_list,
4170 gnu_return_list, returns_unconstrained,
4171 returns_by_ref, returns_by_target_ptr);
4175 = create_subprog_type (gnu_return_type, gnu_stub_param_list,
4176 gnu_return_list, returns_unconstrained,
4177 returns_by_ref, returns_by_target_ptr);
4179 /* A subprogram (something that doesn't return anything) shouldn't
4180 be considered const since there would be no reason for such a
4181 subprogram. Note that procedures with Out (or In Out) parameters
4182 have already been converted into a function with a return type. */
4183 if (TREE_CODE (gnu_return_type) == VOID_TYPE)
4187 = build_qualified_type (gnu_type,
4188 TYPE_QUALS (gnu_type)
4189 | (TYPE_QUAL_CONST * const_flag)
4190 | (TYPE_QUAL_VOLATILE * volatile_flag));
4192 Sloc_to_locus (Sloc (gnat_entity), &input_location);
4196 = build_qualified_type (gnu_stub_type,
4197 TYPE_QUALS (gnu_stub_type)
4198 | (TYPE_QUAL_CONST * const_flag)
4199 | (TYPE_QUAL_VOLATILE * volatile_flag));
4201 /* If we have a builtin decl for that function, check the signatures
4202 compatibilities. If the signatures are compatible, use the builtin
4203 decl. If they are not, we expect the checker predicate to have
4204 posted the appropriate errors, and just continue with what we have
4206 if (gnu_builtin_decl)
4208 tree gnu_builtin_type = TREE_TYPE (gnu_builtin_decl);
4210 if (compatible_signatures_p (gnu_type, gnu_builtin_type))
4212 gnu_decl = gnu_builtin_decl;
4213 gnu_type = gnu_builtin_type;
4218 /* If there was no specified Interface_Name and the external and
4219 internal names of the subprogram are the same, only use the
4220 internal name to allow disambiguation of nested subprograms. */
4221 if (No (Interface_Name (gnat_entity))
4222 && gnu_ext_name == gnu_entity_name)
4223 gnu_ext_name = NULL_TREE;
4225 /* If we are defining the subprogram and it has an Address clause
4226 we must get the address expression from the saved GCC tree for the
4227 subprogram if it has a Freeze_Node. Otherwise, we elaborate
4228 the address expression here since the front-end has guaranteed
4229 in that case that the elaboration has no effects. If there is
4230 an Address clause and we are not defining the object, just
4231 make it a constant. */
4232 if (Present (Address_Clause (gnat_entity)))
4234 tree gnu_address = NULL_TREE;
4238 = (present_gnu_tree (gnat_entity)
4239 ? get_gnu_tree (gnat_entity)
4240 : gnat_to_gnu (Expression (Address_Clause (gnat_entity))));
4242 save_gnu_tree (gnat_entity, NULL_TREE, false);
4244 /* Convert the type of the object to a reference type that can
4245 alias everything as per 13.3(19). */
4247 = build_reference_type_for_mode (gnu_type, ptr_mode, true);
4249 gnu_address = convert (gnu_type, gnu_address);
4252 = create_var_decl (gnu_entity_name, gnu_ext_name, gnu_type,
4253 gnu_address, false, Is_Public (gnat_entity),
4254 extern_flag, false, NULL, gnat_entity);
4255 DECL_BY_REF_P (gnu_decl) = 1;
4258 else if (kind == E_Subprogram_Type)
4259 gnu_decl = create_type_decl (gnu_entity_name, gnu_type, attr_list,
4260 !Comes_From_Source (gnat_entity),
4261 debug_info_p, gnat_entity);
4266 gnu_stub_name = gnu_ext_name;
4267 gnu_ext_name = create_concat_name (gnat_entity, "internal");
4268 public_flag = false;
4271 gnu_decl = create_subprog_decl (gnu_entity_name, gnu_ext_name,
4272 gnu_type, gnu_param_list,
4273 inline_flag, public_flag,
4274 extern_flag, attr_list,
4279 = create_subprog_decl (gnu_entity_name, gnu_stub_name,
4280 gnu_stub_type, gnu_stub_param_list,
4282 extern_flag, attr_list,
4284 SET_DECL_FUNCTION_STUB (gnu_decl, gnu_stub_decl);
4287 /* This is unrelated to the stub built right above. */
4288 DECL_STUBBED_P (gnu_decl)
4289 = Convention (gnat_entity) == Convention_Stubbed;
4294 case E_Incomplete_Type:
4295 case E_Incomplete_Subtype:
4296 case E_Private_Type:
4297 case E_Private_Subtype:
4298 case E_Limited_Private_Type:
4299 case E_Limited_Private_Subtype:
4300 case E_Record_Type_With_Private:
4301 case E_Record_Subtype_With_Private:
4303 /* Get the "full view" of this entity. If this is an incomplete
4304 entity from a limited with, treat its non-limited view as the
4305 full view. Otherwise, use either the full view or the underlying
4306 full view, whichever is present. This is used in all the tests
4309 = (IN (Ekind (gnat_entity), Incomplete_Kind)
4310 && From_With_Type (gnat_entity))
4311 ? Non_Limited_View (gnat_entity)
4312 : Present (Full_View (gnat_entity))
4313 ? Full_View (gnat_entity)
4314 : Underlying_Full_View (gnat_entity);
4316 /* If this is an incomplete type with no full view, it must be a Taft
4317 Amendment type, in which case we return a dummy type. Otherwise,
4318 just get the type from its Etype. */
4321 if (kind == E_Incomplete_Type)
4323 gnu_type = make_dummy_type (gnat_entity);
4324 gnu_decl = TYPE_STUB_DECL (gnu_type);
4328 gnu_decl = gnat_to_gnu_entity (Etype (gnat_entity),
4330 maybe_present = true;
4335 /* If we already made a type for the full view, reuse it. */
4336 else if (present_gnu_tree (full_view))
4338 gnu_decl = get_gnu_tree (full_view);
4342 /* Otherwise, if we are not defining the type now, get the type
4343 from the full view. But always get the type from the full view
4344 for define on use types, since otherwise we won't see them! */
4345 else if (!definition
4346 || (Is_Itype (full_view)
4347 && No (Freeze_Node (gnat_entity)))
4348 || (Is_Itype (gnat_entity)
4349 && No (Freeze_Node (full_view))))
4351 gnu_decl = gnat_to_gnu_entity (full_view, NULL_TREE, 0);
4352 maybe_present = true;
4356 /* For incomplete types, make a dummy type entry which will be
4357 replaced later. Save it as the full declaration's type so
4358 we can do any needed updates when we see it. */
4359 gnu_type = make_dummy_type (gnat_entity);
4360 gnu_decl = TYPE_STUB_DECL (gnu_type);
4361 save_gnu_tree (full_view, gnu_decl, 0);
4365 /* Simple class_wide types are always viewed as their root_type
4366 by Gigi unless an Equivalent_Type is specified. */
4367 case E_Class_Wide_Type:
4368 gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0);
4369 maybe_present = true;
4373 case E_Task_Subtype:
4374 case E_Protected_Type:
4375 case E_Protected_Subtype:
4376 if (type_annotate_only && No (gnat_equiv_type))
4377 gnu_type = void_type_node;
4379 gnu_type = gnat_to_gnu_type (gnat_equiv_type);
4381 maybe_present = true;
4385 gnu_decl = create_label_decl (gnu_entity_name);
4390 /* Nothing at all to do here, so just return an ERROR_MARK and claim
4391 we've already saved it, so we don't try to. */
4392 gnu_decl = error_mark_node;
4400 /* If we had a case where we evaluated another type and it might have
4401 defined this one, handle it here. */
4402 if (maybe_present && present_gnu_tree (gnat_entity))
4404 gnu_decl = get_gnu_tree (gnat_entity);
4408 /* If we are processing a type and there is either no decl for it or
4409 we just made one, do some common processing for the type, such as
4410 handling alignment and possible padding. */
4411 if (is_type && (!gnu_decl || this_made_decl))
4413 if (Is_Tagged_Type (gnat_entity)
4414 || Is_Class_Wide_Equivalent_Type (gnat_entity))
4415 TYPE_ALIGN_OK (gnu_type) = 1;
4417 if (AGGREGATE_TYPE_P (gnu_type) && Is_By_Reference_Type (gnat_entity))
4418 TYPE_BY_REFERENCE_P (gnu_type) = 1;
4420 /* ??? Don't set the size for a String_Literal since it is either
4421 confirming or we don't handle it properly (if the low bound is
4423 if (!gnu_size && kind != E_String_Literal_Subtype)
4424 gnu_size = validate_size (Esize (gnat_entity), gnu_type, gnat_entity,
4426 Has_Size_Clause (gnat_entity));
4428 /* If a size was specified, see if we can make a new type of that size
4429 by rearranging the type, for example from a fat to a thin pointer. */
4433 = make_type_from_size (gnu_type, gnu_size,
4434 Has_Biased_Representation (gnat_entity));
4436 if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0)
4437 && operand_equal_p (rm_size (gnu_type), gnu_size, 0))
4441 /* If the alignment hasn't already been processed and this is
4442 not an unconstrained array, see if an alignment is specified.
4443 If not, we pick a default alignment for atomic objects. */
4444 if (align != 0 || TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE)
4446 else if (Known_Alignment (gnat_entity))
4448 align = validate_alignment (Alignment (gnat_entity), gnat_entity,
4449 TYPE_ALIGN (gnu_type));
4451 /* Warn on suspiciously large alignments. This should catch
4452 errors about the (alignment,byte)/(size,bit) discrepancy. */
4453 if (align > BIGGEST_ALIGNMENT && Has_Alignment_Clause (gnat_entity))
4457 /* If a size was specified, take it into account. Otherwise
4458 use the RM size for records as the type size has already
4459 been adjusted to the alignment. */
4462 else if ((TREE_CODE (gnu_type) == RECORD_TYPE
4463 || TREE_CODE (gnu_type) == UNION_TYPE
4464 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
4465 && !TYPE_IS_FAT_POINTER_P (gnu_type))
4466 size = rm_size (gnu_type);
4468 size = TYPE_SIZE (gnu_type);
4470 /* Consider an alignment as suspicious if the alignment/size
4471 ratio is greater or equal to the byte/bit ratio. */
4472 if (host_integerp (size, 1)
4473 && align >= TREE_INT_CST_LOW (size) * BITS_PER_UNIT)
4474 post_error_ne ("?suspiciously large alignment specified for&",
4475 Expression (Alignment_Clause (gnat_entity)),
4479 else if (Is_Atomic (gnat_entity) && !gnu_size
4480 && host_integerp (TYPE_SIZE (gnu_type), 1)
4481 && integer_pow2p (TYPE_SIZE (gnu_type)))
4482 align = MIN (BIGGEST_ALIGNMENT,
4483 tree_low_cst (TYPE_SIZE (gnu_type), 1));
4484 else if (Is_Atomic (gnat_entity) && gnu_size
4485 && host_integerp (gnu_size, 1)
4486 && integer_pow2p (gnu_size))
4487 align = MIN (BIGGEST_ALIGNMENT, tree_low_cst (gnu_size, 1));
4489 /* See if we need to pad the type. If we did, and made a record,
4490 the name of the new type may be changed. So get it back for
4491 us when we make the new TYPE_DECL below. */
4492 if (gnu_size || align > 0)
4493 gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity,
4494 "PAD", true, definition, false);
4496 if (TREE_CODE (gnu_type) == RECORD_TYPE
4497 && TYPE_IS_PADDING_P (gnu_type))
4499 gnu_entity_name = TYPE_NAME (gnu_type);
4500 if (TREE_CODE (gnu_entity_name) == TYPE_DECL)
4501 gnu_entity_name = DECL_NAME (gnu_entity_name);
4504 set_rm_size (RM_Size (gnat_entity), gnu_type, gnat_entity);
4506 /* If we are at global level, GCC will have applied variable_size to
4507 the type, but that won't have done anything. So, if it's not
4508 a constant or self-referential, call elaborate_expression_1 to
4509 make a variable for the size rather than calculating it each time.
4510 Handle both the RM size and the actual size. */
4511 if (global_bindings_p ()
4512 && TYPE_SIZE (gnu_type)
4513 && !TREE_CONSTANT (TYPE_SIZE (gnu_type))
4514 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)))
4516 if (TREE_CODE (gnu_type) == RECORD_TYPE
4517 && operand_equal_p (TYPE_ADA_SIZE (gnu_type),
4518 TYPE_SIZE (gnu_type), 0))
4520 TYPE_SIZE (gnu_type)
4521 = elaborate_expression_1 (TYPE_SIZE (gnu_type),
4522 gnat_entity, get_identifier ("SIZE"),
4524 SET_TYPE_ADA_SIZE (gnu_type, TYPE_SIZE (gnu_type));
4528 TYPE_SIZE (gnu_type)
4529 = elaborate_expression_1 (TYPE_SIZE (gnu_type),
4530 gnat_entity, get_identifier ("SIZE"),
4533 /* ??? For now, store the size as a multiple of the alignment
4534 in bytes so that we can see the alignment from the tree. */
4535 TYPE_SIZE_UNIT (gnu_type)
4537 (MULT_EXPR, sizetype,
4538 elaborate_expression_1
4539 (build_binary_op (EXACT_DIV_EXPR, sizetype,
4540 TYPE_SIZE_UNIT (gnu_type),
4541 size_int (TYPE_ALIGN (gnu_type)
4543 gnat_entity, get_identifier ("SIZE_A_UNIT"),
4545 size_int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT));
4547 if (TREE_CODE (gnu_type) == RECORD_TYPE)
4550 elaborate_expression_1 (TYPE_ADA_SIZE (gnu_type),
4552 get_identifier ("RM_SIZE"),
4553 definition, false));
4557 /* If this is a record type or subtype, call elaborate_expression_1 on
4558 any field position. Do this for both global and local types.
4559 Skip any fields that we haven't made trees for to avoid problems with
4560 class wide types. */
4561 if (IN (kind, Record_Kind))
4562 for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp);
4563 gnat_temp = Next_Entity (gnat_temp))
4564 if (Ekind (gnat_temp) == E_Component && present_gnu_tree (gnat_temp))
4566 tree gnu_field = get_gnu_tree (gnat_temp);
4568 /* ??? Unfortunately, GCC needs to be able to prove the
4569 alignment of this offset and if it's a variable, it can't.
4570 In GCC 3.4, we'll use DECL_OFFSET_ALIGN in some way, but
4571 right now, we have to put in an explicit multiply and
4572 divide by that value. */
4573 if (!CONTAINS_PLACEHOLDER_P (DECL_FIELD_OFFSET (gnu_field)))
4575 DECL_FIELD_OFFSET (gnu_field)
4577 (MULT_EXPR, sizetype,
4578 elaborate_expression_1
4579 (build_binary_op (EXACT_DIV_EXPR, sizetype,
4580 DECL_FIELD_OFFSET (gnu_field),
4581 size_int (DECL_OFFSET_ALIGN (gnu_field)
4583 gnat_temp, get_identifier ("OFFSET"),
4585 size_int (DECL_OFFSET_ALIGN (gnu_field) / BITS_PER_UNIT));
4587 /* ??? The context of gnu_field is not necessarily gnu_type so
4588 the MULT_EXPR node built above may not be marked by the call
4589 to create_type_decl below. */
4590 if (global_bindings_p ())
4591 mark_visited (&DECL_FIELD_OFFSET (gnu_field));
4595 gnu_type = build_qualified_type (gnu_type,
4596 (TYPE_QUALS (gnu_type)
4597 | (TYPE_QUAL_VOLATILE
4598 * Treat_As_Volatile (gnat_entity))));
4600 if (Is_Atomic (gnat_entity))
4601 check_ok_for_atomic (gnu_type, gnat_entity, false);
4603 if (Present (Alignment_Clause (gnat_entity)))
4604 TYPE_USER_ALIGN (gnu_type) = 1;
4606 if (Universal_Aliasing (gnat_entity))
4607 TYPE_UNIVERSAL_ALIASING_P (TYPE_MAIN_VARIANT (gnu_type)) = 1;
4610 gnu_decl = create_type_decl (gnu_entity_name, gnu_type, attr_list,
4611 !Comes_From_Source (gnat_entity),
4612 debug_info_p, gnat_entity);
4614 TREE_TYPE (gnu_decl) = gnu_type;
4617 if (is_type && !TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl)))
4619 gnu_type = TREE_TYPE (gnu_decl);
4621 /* If this is a derived type, relate its alias set to that of its parent
4622 to avoid troubles when a call to an inherited primitive is inlined in
4623 a context where a derived object is accessed. The inlined code works
4624 on the parent view so the resulting code may access the same object
4625 using both the parent and the derived alias sets, which thus have to
4626 conflict. As the same issue arises with component references, the
4627 parent alias set also has to conflict with composite types enclosing
4628 derived components. For instance, if we have:
4635 we want T to conflict with both D and R, in addition to R being a
4636 superset of D by record/component construction.
4638 One way to achieve this is to perform an alias set copy from the
4639 parent to the derived type. This is not quite appropriate, though,
4640 as we don't want separate derived types to conflict with each other:
4642 type I1 is new Integer;
4643 type I2 is new Integer;
4645 We want I1 and I2 to both conflict with Integer but we do not want
4646 I1 to conflict with I2, and an alias set copy on derivation would
4649 The option chosen is to make the alias set of the derived type a
4650 superset of that of its parent type. It trivially fulfills the
4651 simple requirement for the Integer derivation example above, and
4652 the component case as well by superset transitivity:
4655 R ----------> D ----------> T
4657 The language rules ensure the parent type is already frozen here. */
4658 if (Is_Derived_Type (gnat_entity))
4660 tree gnu_parent_type = gnat_to_gnu_type (Etype (gnat_entity));
4661 relate_alias_sets (gnu_type, gnu_parent_type, ALIAS_SET_SUPERSET);
4664 /* Back-annotate the Alignment of the type if not already in the
4665 tree. Likewise for sizes. */
4666 if (Unknown_Alignment (gnat_entity))
4668 unsigned int double_align, align;
4669 bool is_capped_double, align_clause;
4671 /* If the default alignment of "double" or larger scalar types is
4672 specifically capped and this is not an array with an alignment
4673 clause on the component type, return the cap. */
4674 if ((double_align = double_float_alignment) > 0)
4676 = is_double_float_or_array (gnat_entity, &align_clause);
4677 else if ((double_align = double_scalar_alignment) > 0)
4679 = is_double_scalar_or_array (gnat_entity, &align_clause);
4681 is_capped_double = align_clause = false;
4683 if (is_capped_double && !align_clause)
4684 align = double_align;
4686 align = TYPE_ALIGN (gnu_type) / BITS_PER_UNIT;
4688 Set_Alignment (gnat_entity, UI_From_Int (align));
4691 if (Unknown_Esize (gnat_entity) && TYPE_SIZE (gnu_type))
4693 /* If the size is self-referential, we annotate the maximum
4694 value of that size. */
4695 tree gnu_size = TYPE_SIZE (gnu_type);
4697 if (CONTAINS_PLACEHOLDER_P (gnu_size))
4698 gnu_size = max_size (gnu_size, true);
4700 Set_Esize (gnat_entity, annotate_value (gnu_size));
4702 if (type_annotate_only && Is_Tagged_Type (gnat_entity))
4704 /* In this mode the tag and the parent components are not
4705 generated by the front-end, so the sizes must be adjusted
4707 int size_offset, new_size;
4709 if (Is_Derived_Type (gnat_entity))
4712 = UI_To_Int (Esize (Etype (Base_Type (gnat_entity))));
4713 Set_Alignment (gnat_entity,
4714 Alignment (Etype (Base_Type (gnat_entity))));
4717 size_offset = POINTER_SIZE;
4719 new_size = UI_To_Int (Esize (gnat_entity)) + size_offset;
4720 Set_Esize (gnat_entity,
4721 UI_From_Int (((new_size + (POINTER_SIZE - 1))
4722 / POINTER_SIZE) * POINTER_SIZE));
4723 Set_RM_Size (gnat_entity, Esize (gnat_entity));
4727 if (Unknown_RM_Size (gnat_entity) && rm_size (gnu_type))
4728 Set_RM_Size (gnat_entity, annotate_value (rm_size (gnu_type)));
4731 if (!Comes_From_Source (gnat_entity) && DECL_P (gnu_decl))
4732 DECL_ARTIFICIAL (gnu_decl) = 1;
4734 if (!debug_info_p && DECL_P (gnu_decl)
4735 && TREE_CODE (gnu_decl) != FUNCTION_DECL
4736 && No (Renamed_Object (gnat_entity)))
4737 DECL_IGNORED_P (gnu_decl) = 1;
4739 /* If we haven't already, associate the ..._DECL node that we just made with
4740 the input GNAT entity node. */
4742 save_gnu_tree (gnat_entity, gnu_decl, false);
4744 /* If this is an enumeration or floating-point type, we were not able to set
4745 the bounds since they refer to the type. These are always static. */
4746 if ((kind == E_Enumeration_Type && Present (First_Literal (gnat_entity)))
4747 || (kind == E_Floating_Point_Type && !Vax_Float (gnat_entity)))
4749 tree gnu_scalar_type = gnu_type;
4750 tree gnu_low_bound, gnu_high_bound;
4752 /* If this is a padded type, we need to use the underlying type. */
4753 if (TREE_CODE (gnu_scalar_type) == RECORD_TYPE
4754 && TYPE_IS_PADDING_P (gnu_scalar_type))
4755 gnu_scalar_type = TREE_TYPE (TYPE_FIELDS (gnu_scalar_type));
4757 /* If this is a floating point type and we haven't set a floating
4758 point type yet, use this in the evaluation of the bounds. */
4759 if (!longest_float_type_node && kind == E_Floating_Point_Type)
4760 longest_float_type_node = gnu_scalar_type;
4762 gnu_low_bound = gnat_to_gnu (Type_Low_Bound (gnat_entity));
4763 gnu_high_bound = gnat_to_gnu (Type_High_Bound (gnat_entity));
4765 if (kind == E_Enumeration_Type)
4767 /* Enumeration types have specific RM bounds. */
4768 SET_TYPE_RM_MIN_VALUE (gnu_scalar_type, gnu_low_bound);
4769 SET_TYPE_RM_MAX_VALUE (gnu_scalar_type, gnu_high_bound);
4771 /* Write full debugging information. Since this has both a
4772 typedef and a tag, avoid outputting the name twice. */
4773 DECL_ARTIFICIAL (gnu_decl) = 1;
4774 rest_of_type_decl_compilation (gnu_decl);
4779 /* Floating-point types don't have specific RM bounds. */
4780 TYPE_GCC_MIN_VALUE (gnu_scalar_type) = gnu_low_bound;
4781 TYPE_GCC_MAX_VALUE (gnu_scalar_type) = gnu_high_bound;
4785 /* If we deferred processing of incomplete types, re-enable it. If there
4786 were no other disables and we have some to process, do so. */
4787 if (this_deferred && --defer_incomplete_level == 0)
4789 if (defer_incomplete_list)
4791 struct incomplete *incp, *next;
4793 /* We are back to level 0 for the deferring of incomplete types.
4794 But processing these incomplete types below may itself require
4795 deferring, so preserve what we have and restart from scratch. */
4796 incp = defer_incomplete_list;
4797 defer_incomplete_list = NULL;
4799 /* For finalization, however, all types must be complete so we
4800 cannot do the same because deferred incomplete types may end up
4801 referencing each other. Process them all recursively first. */
4802 defer_finalize_level++;
4804 for (; incp; incp = next)
4809 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4810 gnat_to_gnu_type (incp->full_type));
4814 defer_finalize_level--;
4817 /* All the deferred incomplete types have been processed so we can
4818 now proceed with the finalization of the deferred types. */
4819 if (defer_finalize_level == 0 && defer_finalize_list)
4824 for (i = 0; VEC_iterate (tree, defer_finalize_list, i, t); i++)
4825 rest_of_type_decl_compilation_no_defer (t);
4827 VEC_free (tree, heap, defer_finalize_list);
4831 /* If we are not defining this type, see if it's in the incomplete list.
4832 If so, handle that list entry now. */
4833 else if (!definition)
4835 struct incomplete *incp;
4837 for (incp = defer_incomplete_list; incp; incp = incp->next)
4838 if (incp->old_type && incp->full_type == gnat_entity)
4840 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4841 TREE_TYPE (gnu_decl));
4842 incp->old_type = NULL_TREE;
4849 /* If this is a packed array type whose original array type is itself
4850 an Itype without freeze node, make sure the latter is processed. */
4851 if (Is_Packed_Array_Type (gnat_entity)
4852 && Is_Itype (Original_Array_Type (gnat_entity))
4853 && No (Freeze_Node (Original_Array_Type (gnat_entity)))
4854 && !present_gnu_tree (Original_Array_Type (gnat_entity)))
4855 gnat_to_gnu_entity (Original_Array_Type (gnat_entity), NULL_TREE, 0);
4860 /* Similar, but if the returned value is a COMPONENT_REF, return the
4864 gnat_to_gnu_field_decl (Entity_Id gnat_entity)
4866 tree gnu_field = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0);
4868 if (TREE_CODE (gnu_field) == COMPONENT_REF)
4869 gnu_field = TREE_OPERAND (gnu_field, 1);
4874 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return
4875 the GCC type corresponding to that entity. */
4878 gnat_to_gnu_type (Entity_Id gnat_entity)
4882 /* The back end never attempts to annotate generic types. */
4883 if (Is_Generic_Type (gnat_entity) && type_annotate_only)
4884 return void_type_node;
4886 gnu_decl = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0);
4887 gcc_assert (TREE_CODE (gnu_decl) == TYPE_DECL);
4889 return TREE_TYPE (gnu_decl);
4892 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return
4893 the unpadded version of the GCC type corresponding to that entity. */
4896 get_unpadded_type (Entity_Id gnat_entity)
4898 tree type = gnat_to_gnu_type (gnat_entity);
4900 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
4901 type = TREE_TYPE (TYPE_FIELDS (type));
4906 /* Wrap up compilation of DECL, a TYPE_DECL, possibly deferring it.
4907 Every TYPE_DECL generated for a type definition must be passed
4908 to this function once everything else has been done for it. */
4911 rest_of_type_decl_compilation (tree decl)
4913 /* We need to defer finalizing the type if incomplete types
4914 are being deferred or if they are being processed. */
4915 if (defer_incomplete_level || defer_finalize_level)
4916 VEC_safe_push (tree, heap, defer_finalize_list, decl);
4918 rest_of_type_decl_compilation_no_defer (decl);
4921 /* Same as above but without deferring the compilation. This
4922 function should not be invoked directly on a TYPE_DECL. */
4925 rest_of_type_decl_compilation_no_defer (tree decl)
4927 const int toplev = global_bindings_p ();
4928 tree t = TREE_TYPE (decl);
4930 rest_of_decl_compilation (decl, toplev, 0);
4932 /* Now process all the variants. This is needed for STABS. */
4933 for (t = TYPE_MAIN_VARIANT (t); t; t = TYPE_NEXT_VARIANT (t))
4935 if (t == TREE_TYPE (decl))
4938 if (!TYPE_STUB_DECL (t))
4939 TYPE_STUB_DECL (t) = create_type_stub_decl (DECL_NAME (decl), t);
4941 rest_of_type_compilation (t, toplev);
4945 /* Finalize any From_With_Type incomplete types. We do this after processing
4946 our compilation unit and after processing its spec, if this is a body. */
4949 finalize_from_with_types (void)
4951 struct incomplete *incp = defer_limited_with;
4952 struct incomplete *next;
4954 defer_limited_with = 0;
4955 for (; incp; incp = next)
4959 if (incp->old_type != 0)
4960 update_pointer_to (TYPE_MAIN_VARIANT (incp->old_type),
4961 gnat_to_gnu_type (incp->full_type));
4966 /* Return the equivalent type to be used for GNAT_ENTITY, if it's a
4967 kind of type (such E_Task_Type) that has a different type which Gigi
4968 uses for its representation. If the type does not have a special type
4969 for its representation, return GNAT_ENTITY. If a type is supposed to
4970 exist, but does not, abort unless annotating types, in which case
4971 return Empty. If GNAT_ENTITY is Empty, return Empty. */
4974 Gigi_Equivalent_Type (Entity_Id gnat_entity)
4976 Entity_Id gnat_equiv = gnat_entity;
4978 if (No (gnat_entity))
4981 switch (Ekind (gnat_entity))
4983 case E_Class_Wide_Subtype:
4984 if (Present (Equivalent_Type (gnat_entity)))
4985 gnat_equiv = Equivalent_Type (gnat_entity);
4988 case E_Access_Protected_Subprogram_Type:
4989 case E_Anonymous_Access_Protected_Subprogram_Type:
4990 gnat_equiv = Equivalent_Type (gnat_entity);
4993 case E_Class_Wide_Type:
4994 gnat_equiv = ((Present (Equivalent_Type (gnat_entity)))
4995 ? Equivalent_Type (gnat_entity)
4996 : Root_Type (gnat_entity));
5000 case E_Task_Subtype:
5001 case E_Protected_Type:
5002 case E_Protected_Subtype:
5003 gnat_equiv = Corresponding_Record_Type (gnat_entity);
5010 gcc_assert (Present (gnat_equiv) || type_annotate_only);
5014 /* Return a GCC tree for a parameter corresponding to GNAT_PARAM and
5015 using MECH as its passing mechanism, to be placed in the parameter
5016 list built for GNAT_SUBPROG. Assume a foreign convention for the
5017 latter if FOREIGN is true. Also set CICO to true if the parameter
5018 must use the copy-in copy-out implementation mechanism.
5020 The returned tree is a PARM_DECL, except for those cases where no
5021 parameter needs to be actually passed to the subprogram; the type
5022 of this "shadow" parameter is then returned instead. */
5025 gnat_to_gnu_param (Entity_Id gnat_param, Mechanism_Type mech,
5026 Entity_Id gnat_subprog, bool foreign, bool *cico)
5028 tree gnu_param_name = get_entity_name (gnat_param);
5029 tree gnu_param_type = gnat_to_gnu_type (Etype (gnat_param));
5030 tree gnu_param_type_alt = NULL_TREE;
5031 bool in_param = (Ekind (gnat_param) == E_In_Parameter);
5032 /* The parameter can be indirectly modified if its address is taken. */
5033 bool ro_param = in_param && !Address_Taken (gnat_param);
5034 bool by_return = false, by_component_ptr = false, by_ref = false;
5037 /* Copy-return is used only for the first parameter of a valued procedure.
5038 It's a copy mechanism for which a parameter is never allocated. */
5039 if (mech == By_Copy_Return)
5041 gcc_assert (Ekind (gnat_param) == E_Out_Parameter);
5046 /* If this is either a foreign function or if the underlying type won't
5047 be passed by reference, strip off possible padding type. */
5048 if (TREE_CODE (gnu_param_type) == RECORD_TYPE
5049 && TYPE_IS_PADDING_P (gnu_param_type))
5051 tree unpadded_type = TREE_TYPE (TYPE_FIELDS (gnu_param_type));
5053 if (mech == By_Reference
5055 || (!must_pass_by_ref (unpadded_type)
5056 && (mech == By_Copy || !default_pass_by_ref (unpadded_type))))
5057 gnu_param_type = unpadded_type;
5060 /* If this is a read-only parameter, make a variant of the type that is
5061 read-only. ??? However, if this is an unconstrained array, that type
5062 can be very complex, so skip it for now. Likewise for any other
5063 self-referential type. */
5065 && TREE_CODE (gnu_param_type) != UNCONSTRAINED_ARRAY_TYPE
5066 && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_param_type)))
5067 gnu_param_type = build_qualified_type (gnu_param_type,
5068 (TYPE_QUALS (gnu_param_type)
5069 | TYPE_QUAL_CONST));
5071 /* For foreign conventions, pass arrays as pointers to the element type.
5072 First check for unconstrained array and get the underlying array. */
5073 if (foreign && TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE)
5075 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_param_type))));
5077 /* VMS descriptors are themselves passed by reference. */
5078 if (mech == By_Short_Descriptor ||
5079 (mech == By_Descriptor && TARGET_ABI_OPEN_VMS && !TARGET_MALLOC64))
5081 = build_pointer_type (build_vms_descriptor32 (gnu_param_type,
5082 Mechanism (gnat_param),
5084 else if (mech == By_Descriptor)
5086 /* Build both a 32-bit and 64-bit descriptor, one of which will be
5087 chosen in fill_vms_descriptor. */
5089 = build_pointer_type (build_vms_descriptor32 (gnu_param_type,
5090 Mechanism (gnat_param),
5093 = build_pointer_type (build_vms_descriptor (gnu_param_type,
5094 Mechanism (gnat_param),
5098 /* Arrays are passed as pointers to element type for foreign conventions. */
5101 && TREE_CODE (gnu_param_type) == ARRAY_TYPE)
5103 /* Strip off any multi-dimensional entries, then strip
5104 off the last array to get the component type. */
5105 while (TREE_CODE (TREE_TYPE (gnu_param_type)) == ARRAY_TYPE
5106 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_param_type)))
5107 gnu_param_type = TREE_TYPE (gnu_param_type);
5109 by_component_ptr = true;
5110 gnu_param_type = TREE_TYPE (gnu_param_type);
5113 gnu_param_type = build_qualified_type (gnu_param_type,
5114 (TYPE_QUALS (gnu_param_type)
5115 | TYPE_QUAL_CONST));
5117 gnu_param_type = build_pointer_type (gnu_param_type);
5120 /* Fat pointers are passed as thin pointers for foreign conventions. */
5121 else if (foreign && TYPE_FAT_POINTER_P (gnu_param_type))
5123 = make_type_from_size (gnu_param_type, size_int (POINTER_SIZE), 0);
5125 /* If we must pass or were requested to pass by reference, do so.
5126 If we were requested to pass by copy, do so.
5127 Otherwise, for foreign conventions, pass In Out or Out parameters
5128 or aggregates by reference. For COBOL and Fortran, pass all
5129 integer and FP types that way too. For Convention Ada, use
5130 the standard Ada default. */
5131 else if (must_pass_by_ref (gnu_param_type)
5132 || mech == By_Reference
5135 && (!in_param || AGGREGATE_TYPE_P (gnu_param_type)))
5137 && (Convention (gnat_subprog) == Convention_Fortran
5138 || Convention (gnat_subprog) == Convention_COBOL)
5139 && (INTEGRAL_TYPE_P (gnu_param_type)
5140 || FLOAT_TYPE_P (gnu_param_type)))
5142 && default_pass_by_ref (gnu_param_type)))))
5144 gnu_param_type = build_reference_type (gnu_param_type);
5148 /* Pass In Out or Out parameters using copy-in copy-out mechanism. */
5152 if (mech == By_Copy && (by_ref || by_component_ptr))
5153 post_error ("?cannot pass & by copy", gnat_param);
5155 /* If this is an Out parameter that isn't passed by reference and isn't
5156 a pointer or aggregate, we don't make a PARM_DECL for it. Instead,
5157 it will be a VAR_DECL created when we process the procedure, so just
5158 return its type. For the special parameter of a valued procedure,
5161 An exception is made to cover the RM-6.4.1 rule requiring "by copy"
5162 Out parameters with discriminants or implicit initial values to be
5163 handled like In Out parameters. These type are normally built as
5164 aggregates, hence passed by reference, except for some packed arrays
5165 which end up encoded in special integer types.
5167 The exception we need to make is then for packed arrays of records
5168 with discriminants or implicit initial values. We have no light/easy
5169 way to check for the latter case, so we merely check for packed arrays
5170 of records. This may lead to useless copy-in operations, but in very
5171 rare cases only, as these would be exceptions in a set of already
5172 exceptional situations. */
5173 if (Ekind (gnat_param) == E_Out_Parameter
5176 || (mech != By_Descriptor
5177 && mech != By_Short_Descriptor
5178 && !POINTER_TYPE_P (gnu_param_type)
5179 && !AGGREGATE_TYPE_P (gnu_param_type)))
5180 && !(Is_Array_Type (Etype (gnat_param))
5181 && Is_Packed (Etype (gnat_param))
5182 && Is_Composite_Type (Component_Type (Etype (gnat_param)))))
5183 return gnu_param_type;
5185 gnu_param = create_param_decl (gnu_param_name, gnu_param_type,
5186 ro_param || by_ref || by_component_ptr);
5187 DECL_BY_REF_P (gnu_param) = by_ref;
5188 DECL_BY_COMPONENT_PTR_P (gnu_param) = by_component_ptr;
5189 DECL_BY_DESCRIPTOR_P (gnu_param) = (mech == By_Descriptor ||
5190 mech == By_Short_Descriptor);
5191 DECL_POINTS_TO_READONLY_P (gnu_param)
5192 = (ro_param && (by_ref || by_component_ptr));
5194 /* Save the alternate descriptor type, if any. */
5195 if (gnu_param_type_alt)
5196 SET_DECL_PARM_ALT_TYPE (gnu_param, gnu_param_type_alt);
5198 /* If no Mechanism was specified, indicate what we're using, then
5199 back-annotate it. */
5200 if (mech == Default)
5201 mech = (by_ref || by_component_ptr) ? By_Reference : By_Copy;
5203 Set_Mechanism (gnat_param, mech);
5207 /* Return true if DISCR1 and DISCR2 represent the same discriminant. */
5210 same_discriminant_p (Entity_Id discr1, Entity_Id discr2)
5212 while (Present (Corresponding_Discriminant (discr1)))
5213 discr1 = Corresponding_Discriminant (discr1);
5215 while (Present (Corresponding_Discriminant (discr2)))
5216 discr2 = Corresponding_Discriminant (discr2);
5219 Original_Record_Component (discr1) == Original_Record_Component (discr2);
5222 /* Return true if the array type specified by GNAT_TYPE and GNU_TYPE has
5223 a non-aliased component in the back-end sense. */
5226 array_type_has_nonaliased_component (Entity_Id gnat_type, tree gnu_type)
5228 /* If the type below this is a multi-array type, then
5229 this does not have aliased components. */
5230 if (TREE_CODE (TREE_TYPE (gnu_type)) == ARRAY_TYPE
5231 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type)))
5234 if (Has_Aliased_Components (gnat_type))
5237 return type_for_nonaliased_component_p (TREE_TYPE (gnu_type));
5240 /* Return true if GNAT_ADDRESS is a value known at compile-time. */
5243 compile_time_known_address_p (Node_Id gnat_address)
5245 /* Catch System'To_Address. */
5246 if (Nkind (gnat_address) == N_Unchecked_Type_Conversion)
5247 gnat_address = Expression (gnat_address);
5249 return Compile_Time_Known_Value (gnat_address);
5252 /* Given GNAT_ENTITY, elaborate all expressions that are required to
5253 be elaborated at the point of its definition, but do nothing else. */
5256 elaborate_entity (Entity_Id gnat_entity)
5258 switch (Ekind (gnat_entity))
5260 case E_Signed_Integer_Subtype:
5261 case E_Modular_Integer_Subtype:
5262 case E_Enumeration_Subtype:
5263 case E_Ordinary_Fixed_Point_Subtype:
5264 case E_Decimal_Fixed_Point_Subtype:
5265 case E_Floating_Point_Subtype:
5267 Node_Id gnat_lb = Type_Low_Bound (gnat_entity);
5268 Node_Id gnat_hb = Type_High_Bound (gnat_entity);
5270 /* ??? Tests to avoid Constraint_Error in static expressions
5271 are needed until after the front stops generating bogus
5272 conversions on bounds of real types. */
5273 if (!Raises_Constraint_Error (gnat_lb))
5274 elaborate_expression (gnat_lb, gnat_entity, get_identifier ("L"),
5275 true, false, Needs_Debug_Info (gnat_entity));
5276 if (!Raises_Constraint_Error (gnat_hb))
5277 elaborate_expression (gnat_hb, gnat_entity, get_identifier ("U"),
5278 true, false, Needs_Debug_Info (gnat_entity));
5284 Node_Id full_definition = Declaration_Node (gnat_entity);
5285 Node_Id record_definition = Type_Definition (full_definition);
5287 /* If this is a record extension, go a level further to find the
5288 record definition. */
5289 if (Nkind (record_definition) == N_Derived_Type_Definition)
5290 record_definition = Record_Extension_Part (record_definition);
5294 case E_Record_Subtype:
5295 case E_Private_Subtype:
5296 case E_Limited_Private_Subtype:
5297 case E_Record_Subtype_With_Private:
5298 if (Is_Constrained (gnat_entity)
5299 && Has_Discriminants (Base_Type (gnat_entity))
5300 && Present (Discriminant_Constraint (gnat_entity)))
5302 Node_Id gnat_discriminant_expr;
5303 Entity_Id gnat_field;
5305 for (gnat_field = First_Discriminant (Base_Type (gnat_entity)),
5306 gnat_discriminant_expr
5307 = First_Elmt (Discriminant_Constraint (gnat_entity));
5308 Present (gnat_field);
5309 gnat_field = Next_Discriminant (gnat_field),
5310 gnat_discriminant_expr = Next_Elmt (gnat_discriminant_expr))
5311 /* ??? For now, ignore access discriminants. */
5312 if (!Is_Access_Type (Etype (Node (gnat_discriminant_expr))))
5313 elaborate_expression (Node (gnat_discriminant_expr),
5314 gnat_entity, get_entity_name (gnat_field),
5315 true, false, false);
5322 /* Mark GNAT_ENTITY as going out of scope at this point. Recursively mark
5323 any entities on its entity chain similarly. */
5326 mark_out_of_scope (Entity_Id gnat_entity)
5328 Entity_Id gnat_sub_entity;
5329 unsigned int kind = Ekind (gnat_entity);
5331 /* If this has an entity list, process all in the list. */
5332 if (IN (kind, Class_Wide_Kind) || IN (kind, Concurrent_Kind)
5333 || IN (kind, Private_Kind)
5334 || kind == E_Block || kind == E_Entry || kind == E_Entry_Family
5335 || kind == E_Function || kind == E_Generic_Function
5336 || kind == E_Generic_Package || kind == E_Generic_Procedure
5337 || kind == E_Loop || kind == E_Operator || kind == E_Package
5338 || kind == E_Package_Body || kind == E_Procedure
5339 || kind == E_Record_Type || kind == E_Record_Subtype
5340 || kind == E_Subprogram_Body || kind == E_Subprogram_Type)
5341 for (gnat_sub_entity = First_Entity (gnat_entity);
5342 Present (gnat_sub_entity);
5343 gnat_sub_entity = Next_Entity (gnat_sub_entity))
5344 if (Scope (gnat_sub_entity) == gnat_entity
5345 && gnat_sub_entity != gnat_entity)
5346 mark_out_of_scope (gnat_sub_entity);
5348 /* Now clear this if it has been defined, but only do so if it isn't
5349 a subprogram or parameter. We could refine this, but it isn't
5350 worth it. If this is statically allocated, it is supposed to
5351 hang around out of cope. */
5352 if (present_gnu_tree (gnat_entity) && !Is_Statically_Allocated (gnat_entity)
5353 && kind != E_Procedure && kind != E_Function && !IN (kind, Formal_Kind))
5355 save_gnu_tree (gnat_entity, NULL_TREE, true);
5356 save_gnu_tree (gnat_entity, error_mark_node, true);
5360 /* Relate the alias sets of GNU_NEW_TYPE and GNU_OLD_TYPE according to OP.
5361 If this is a multi-dimensional array type, do this recursively.
5364 - ALIAS_SET_COPY: the new set is made a copy of the old one.
5365 - ALIAS_SET_SUPERSET: the new set is made a superset of the old one.
5366 - ALIAS_SET_SUBSET: the new set is made a subset of the old one. */
5369 relate_alias_sets (tree gnu_new_type, tree gnu_old_type, enum alias_set_op op)
5371 /* Remove any padding from GNU_OLD_TYPE. It doesn't matter in the case
5372 of a one-dimensional array, since the padding has the same alias set
5373 as the field type, but if it's a multi-dimensional array, we need to
5374 see the inner types. */
5375 while (TREE_CODE (gnu_old_type) == RECORD_TYPE
5376 && (TYPE_JUSTIFIED_MODULAR_P (gnu_old_type)
5377 || TYPE_IS_PADDING_P (gnu_old_type)))
5378 gnu_old_type = TREE_TYPE (TYPE_FIELDS (gnu_old_type));
5380 /* Unconstrained array types are deemed incomplete and would thus be given
5381 alias set 0. Retrieve the underlying array type. */
5382 if (TREE_CODE (gnu_old_type) == UNCONSTRAINED_ARRAY_TYPE)
5384 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_old_type))));
5385 if (TREE_CODE (gnu_new_type) == UNCONSTRAINED_ARRAY_TYPE)
5387 = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_new_type))));
5389 if (TREE_CODE (gnu_new_type) == ARRAY_TYPE
5390 && TREE_CODE (TREE_TYPE (gnu_new_type)) == ARRAY_TYPE
5391 && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_new_type)))
5392 relate_alias_sets (TREE_TYPE (gnu_new_type), TREE_TYPE (gnu_old_type), op);
5396 case ALIAS_SET_COPY:
5397 /* The alias set shouldn't be copied between array types with different
5398 aliasing settings because this can break the aliasing relationship
5399 between the array type and its element type. */
5400 #ifndef ENABLE_CHECKING
5401 if (flag_strict_aliasing)
5403 gcc_assert (!(TREE_CODE (gnu_new_type) == ARRAY_TYPE
5404 && TREE_CODE (gnu_old_type) == ARRAY_TYPE
5405 && TYPE_NONALIASED_COMPONENT (gnu_new_type)
5406 != TYPE_NONALIASED_COMPONENT (gnu_old_type)));
5408 TYPE_ALIAS_SET (gnu_new_type) = get_alias_set (gnu_old_type);
5411 case ALIAS_SET_SUBSET:
5412 case ALIAS_SET_SUPERSET:
5414 alias_set_type old_set = get_alias_set (gnu_old_type);
5415 alias_set_type new_set = get_alias_set (gnu_new_type);
5417 /* Do nothing if the alias sets conflict. This ensures that we
5418 never call record_alias_subset several times for the same pair
5419 or at all for alias set 0. */
5420 if (!alias_sets_conflict_p (old_set, new_set))
5422 if (op == ALIAS_SET_SUBSET)
5423 record_alias_subset (old_set, new_set);
5425 record_alias_subset (new_set, old_set);
5434 record_component_aliases (gnu_new_type);
5437 /* Return a TREE_LIST describing the substitutions needed to reflect
5438 discriminant substitutions from GNAT_SUBTYPE to GNAT_TYPE and add
5439 them to GNU_LIST. If GNAT_TYPE is not specified, use the base type
5440 of GNAT_SUBTYPE. The substitutions can be in any order. TREE_PURPOSE
5441 gives the tree for the discriminant and TREE_VALUES is the replacement
5442 value. They are in the form of operands to substitute_in_expr.
5443 DEFINITION is as in gnat_to_gnu_entity. */
5446 substitution_list (Entity_Id gnat_subtype, Entity_Id gnat_type,
5447 tree gnu_list, bool definition)
5449 Entity_Id gnat_discrim;
5453 gnat_type = Implementation_Base_Type (gnat_subtype);
5455 if (Has_Discriminants (gnat_type))
5456 for (gnat_discrim = First_Stored_Discriminant (gnat_type),
5457 gnat_value = First_Elmt (Stored_Constraint (gnat_subtype));
5458 Present (gnat_discrim);
5459 gnat_discrim = Next_Stored_Discriminant (gnat_discrim),
5460 gnat_value = Next_Elmt (gnat_value))
5461 /* Ignore access discriminants. */
5462 if (!Is_Access_Type (Etype (Node (gnat_value))))
5463 gnu_list = tree_cons (gnat_to_gnu_field_decl (gnat_discrim),
5464 elaborate_expression
5465 (Node (gnat_value), gnat_subtype,
5466 get_entity_name (gnat_discrim), definition,
5473 /* Return true if the size represented by GNU_SIZE can be handled by an
5474 allocation. If STATIC_P is true, consider only what can be done with a
5475 static allocation. */
5478 allocatable_size_p (tree gnu_size, bool static_p)
5480 HOST_WIDE_INT our_size;
5482 /* If this is not a static allocation, the only case we want to forbid
5483 is an overflowing size. That will be converted into a raise a
5486 return !(TREE_CODE (gnu_size) == INTEGER_CST
5487 && TREE_OVERFLOW (gnu_size));
5489 /* Otherwise, we need to deal with both variable sizes and constant
5490 sizes that won't fit in a host int. We use int instead of HOST_WIDE_INT
5491 since assemblers may not like very large sizes. */
5492 if (!host_integerp (gnu_size, 1))
5495 our_size = tree_low_cst (gnu_size, 1);
5496 return (int) our_size == our_size;
5499 /* Prepend to ATTR_LIST an entry for an attribute with provided TYPE,
5500 NAME, ARGS and ERROR_POINT. */
5503 prepend_one_attribute_to (struct attrib ** attr_list,
5504 enum attr_type attr_type,
5507 Node_Id attr_error_point)
5509 struct attrib * attr = (struct attrib *) xmalloc (sizeof (struct attrib));
5511 attr->type = attr_type;
5512 attr->name = attr_name;
5513 attr->args = attr_args;
5514 attr->error_point = attr_error_point;
5516 attr->next = *attr_list;
5520 /* Prepend to ATTR_LIST the list of attributes for GNAT_ENTITY, if any. */
5523 prepend_attributes (Entity_Id gnat_entity, struct attrib ** attr_list)
5527 for (gnat_temp = First_Rep_Item (gnat_entity); Present (gnat_temp);
5528 gnat_temp = Next_Rep_Item (gnat_temp))
5529 if (Nkind (gnat_temp) == N_Pragma)
5531 tree gnu_arg0 = NULL_TREE, gnu_arg1 = NULL_TREE;
5532 Node_Id gnat_assoc = Pragma_Argument_Associations (gnat_temp);
5533 enum attr_type etype;
5535 if (Present (gnat_assoc) && Present (First (gnat_assoc))
5536 && Present (Next (First (gnat_assoc)))
5537 && (Nkind (Expression (Next (First (gnat_assoc))))
5538 == N_String_Literal))
5540 gnu_arg0 = get_identifier (TREE_STRING_POINTER
5543 (First (gnat_assoc))))));
5544 if (Present (Next (Next (First (gnat_assoc))))
5545 && (Nkind (Expression (Next (Next (First (gnat_assoc)))))
5546 == N_String_Literal))
5547 gnu_arg1 = get_identifier (TREE_STRING_POINTER
5551 (First (gnat_assoc)))))));
5554 switch (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_temp))))
5556 case Pragma_Machine_Attribute:
5557 etype = ATTR_MACHINE_ATTRIBUTE;
5560 case Pragma_Linker_Alias:
5561 etype = ATTR_LINK_ALIAS;
5564 case Pragma_Linker_Section:
5565 etype = ATTR_LINK_SECTION;
5568 case Pragma_Linker_Constructor:
5569 etype = ATTR_LINK_CONSTRUCTOR;
5572 case Pragma_Linker_Destructor:
5573 etype = ATTR_LINK_DESTRUCTOR;
5576 case Pragma_Weak_External:
5577 etype = ATTR_WEAK_EXTERNAL;
5580 case Pragma_Thread_Local_Storage:
5581 etype = ATTR_THREAD_LOCAL_STORAGE;
5589 /* Prepend to the list now. Make a list of the argument we might
5590 have, as GCC expects it. */
5591 prepend_one_attribute_to
5594 (gnu_arg1 != NULL_TREE)
5595 ? build_tree_list (NULL_TREE, gnu_arg1) : NULL_TREE,
5596 Present (Next (First (gnat_assoc)))
5597 ? Expression (Next (First (gnat_assoc))) : gnat_temp);
5601 /* Called when we need to protect a variable object using a SAVE_EXPR. */
5604 maybe_variable (tree gnu_operand)
5606 if (TREE_CONSTANT (gnu_operand)
5607 || TREE_READONLY (gnu_operand)
5608 || TREE_CODE (gnu_operand) == SAVE_EXPR
5609 || TREE_CODE (gnu_operand) == NULL_EXPR)
5612 if (TREE_CODE (gnu_operand) == UNCONSTRAINED_ARRAY_REF)
5615 = build1 (UNCONSTRAINED_ARRAY_REF, TREE_TYPE (gnu_operand),
5616 variable_size (TREE_OPERAND (gnu_operand, 0)));
5618 TREE_READONLY (gnu_result) = TREE_STATIC (gnu_result)
5619 = TYPE_READONLY (TREE_TYPE (TREE_TYPE (gnu_operand)));
5623 return variable_size (gnu_operand);
5626 /* Given a GNAT tree GNAT_EXPR, for an expression which is a value within a
5627 type definition (either a bound or a discriminant value) for GNAT_ENTITY,
5628 return the GCC tree to use for that expression. GNU_NAME is the suffix
5629 to use if a variable needs to be created and DEFINITION is true if this
5630 is a definition of GNAT_ENTITY. If NEED_VALUE is true, we need a result;
5631 otherwise, we are just elaborating the expression for side-effects. If
5632 NEED_DEBUG is true, we need a variable for debugging purposes even if it
5633 isn't needed for code generation. */
5636 elaborate_expression (Node_Id gnat_expr, Entity_Id gnat_entity, tree gnu_name,
5637 bool definition, bool need_value, bool need_debug)
5641 /* If we already elaborated this expression (e.g. it was involved
5642 in the definition of a private type), use the old value. */
5643 if (present_gnu_tree (gnat_expr))
5644 return get_gnu_tree (gnat_expr);
5646 /* If we don't need a value and this is static or a discriminant,
5647 we don't need to do anything. */
5649 && (Is_OK_Static_Expression (gnat_expr)
5650 || (Nkind (gnat_expr) == N_Identifier
5651 && Ekind (Entity (gnat_expr)) == E_Discriminant)))
5654 /* If it's a static expression, we don't need a variable for debugging. */
5655 if (need_debug && Is_OK_Static_Expression (gnat_expr))
5658 /* Otherwise, convert this tree to its GCC equivalent and elaborate it. */
5659 gnu_expr = elaborate_expression_1 (gnat_to_gnu (gnat_expr), gnat_entity,
5660 gnu_name, definition, need_debug);
5662 /* Save the expression in case we try to elaborate this entity again. Since
5663 it's not a DECL, don't check it. Don't save if it's a discriminant. */
5664 if (!CONTAINS_PLACEHOLDER_P (gnu_expr))
5665 save_gnu_tree (gnat_expr, gnu_expr, true);
5667 return need_value ? gnu_expr : error_mark_node;
5670 /* Similar, but take a GNU expression and always return a result. */
5673 elaborate_expression_1 (tree gnu_expr, Entity_Id gnat_entity, tree gnu_name,
5674 bool definition, bool need_debug)
5676 /* Skip any conversions and simple arithmetics to see if the expression
5677 is a read-only variable.
5678 ??? This really should remain read-only, but we have to think about
5679 the typing of the tree here. */
5681 = skip_simple_arithmetic (remove_conversions (gnu_expr, true));
5682 tree gnu_decl = NULL_TREE;
5683 bool expr_global = Is_Public (gnat_entity) || global_bindings_p ();
5686 /* In most cases, we won't see a naked FIELD_DECL because a discriminant
5687 reference will have been replaced with a COMPONENT_REF when the type
5688 is being elaborated. However, there are some cases involving child
5689 types where we will. So convert it to a COMPONENT_REF. We hope it
5690 will be at the highest level of the expression in these cases. */
5691 if (TREE_CODE (gnu_expr) == FIELD_DECL)
5692 gnu_expr = build3 (COMPONENT_REF, TREE_TYPE (gnu_expr),
5693 build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (gnu_expr)),
5694 gnu_expr, NULL_TREE);
5696 /* If GNU_EXPR is neither a placeholder nor a constant, nor a variable
5697 that is read-only, make a variable that is initialized to contain the
5698 bound when the package containing the definition is elaborated. If
5699 this entity is defined at top level and a bound or discriminant value
5700 isn't a constant or a reference to a discriminant, replace the bound
5701 by the variable; otherwise use a SAVE_EXPR if needed. Note that we
5702 rely here on the fact that an expression cannot contain both the
5703 discriminant and some other variable. */
5704 expr_variable = (!CONSTANT_CLASS_P (gnu_expr)
5705 && !(TREE_CODE (gnu_inner_expr) == VAR_DECL
5706 && (TREE_READONLY (gnu_inner_expr)
5707 || DECL_READONLY_ONCE_ELAB (gnu_inner_expr)))
5708 && !CONTAINS_PLACEHOLDER_P (gnu_expr));
5710 /* If GNU_EXPR contains a discriminant, we can't elaborate a variable. */
5711 if (need_debug && CONTAINS_PLACEHOLDER_P (gnu_expr))
5714 /* Now create the variable if we need it. */
5715 if (need_debug || (expr_variable && expr_global))
5717 = create_var_decl (create_concat_name (gnat_entity,
5718 IDENTIFIER_POINTER (gnu_name)),
5719 NULL_TREE, TREE_TYPE (gnu_expr), gnu_expr,
5720 !need_debug, Is_Public (gnat_entity),
5721 !definition, false, NULL, gnat_entity);
5723 /* We only need to use this variable if we are in global context since GCC
5724 can do the right thing in the local case. */
5725 if (expr_global && expr_variable)
5728 return expr_variable ? maybe_variable (gnu_expr) : gnu_expr;
5731 /* Create a record type that contains a SIZE bytes long field of TYPE with a
5732 starting bit position so that it is aligned to ALIGN bits, and leaving at
5733 least ROOM bytes free before the field. BASE_ALIGN is the alignment the
5734 record is guaranteed to get. */
5737 make_aligning_type (tree type, unsigned int align, tree size,
5738 unsigned int base_align, int room)
5740 /* We will be crafting a record type with one field at a position set to be
5741 the next multiple of ALIGN past record'address + room bytes. We use a
5742 record placeholder to express record'address. */
5744 tree record_type = make_node (RECORD_TYPE);
5745 tree record = build0 (PLACEHOLDER_EXPR, record_type);
5748 = convert (sizetype, build_unary_op (ADDR_EXPR, NULL_TREE, record));
5750 /* The diagram below summarizes the shape of what we manipulate:
5752 <--------- pos ---------->
5753 { +------------+-------------+-----------------+
5754 record =>{ |############| ... | field (type) |
5755 { +------------+-------------+-----------------+
5756 |<-- room -->|<- voffset ->|<---- size ----->|
5759 record_addr vblock_addr
5761 Every length is in sizetype bytes there, except "pos" which has to be
5762 set as a bit position in the GCC tree for the record. */
5764 tree room_st = size_int (room);
5765 tree vblock_addr_st = size_binop (PLUS_EXPR, record_addr_st, room_st);
5766 tree voffset_st, pos, field;
5768 tree name = TYPE_NAME (type);
5770 if (TREE_CODE (name) == TYPE_DECL)
5771 name = DECL_NAME (name);
5773 TYPE_NAME (record_type) = concat_name (name, "_ALIGN");
5775 /* Compute VOFFSET and then POS. The next byte position multiple of some
5776 alignment after some address is obtained by "and"ing the alignment minus
5777 1 with the two's complement of the address. */
5779 voffset_st = size_binop (BIT_AND_EXPR,
5780 size_diffop (size_zero_node, vblock_addr_st),
5781 ssize_int ((align / BITS_PER_UNIT) - 1));
5783 /* POS = (ROOM + VOFFSET) * BIT_PER_UNIT, in bitsizetype. */
5785 pos = size_binop (MULT_EXPR,
5786 convert (bitsizetype,
5787 size_binop (PLUS_EXPR, room_st, voffset_st)),
5790 /* Craft the GCC record representation. We exceptionally do everything
5791 manually here because 1) our generic circuitry is not quite ready to
5792 handle the complex position/size expressions we are setting up, 2) we
5793 have a strong simplifying factor at hand: we know the maximum possible
5794 value of voffset, and 3) we have to set/reset at least the sizes in
5795 accordance with this maximum value anyway, as we need them to convey
5796 what should be "alloc"ated for this type.
5798 Use -1 as the 'addressable' indication for the field to prevent the
5799 creation of a bitfield. We don't need one, it would have damaging
5800 consequences on the alignment computation, and create_field_decl would
5801 make one without this special argument, for instance because of the
5802 complex position expression. */
5804 field = create_field_decl (get_identifier ("F"), type, record_type,
5806 TYPE_FIELDS (record_type) = field;
5808 TYPE_ALIGN (record_type) = base_align;
5809 TYPE_USER_ALIGN (record_type) = 1;
5811 TYPE_SIZE (record_type)
5812 = size_binop (PLUS_EXPR,
5813 size_binop (MULT_EXPR, convert (bitsizetype, size),
5815 bitsize_int (align + room * BITS_PER_UNIT));
5816 TYPE_SIZE_UNIT (record_type)
5817 = size_binop (PLUS_EXPR, size,
5818 size_int (room + align / BITS_PER_UNIT));
5820 SET_TYPE_MODE (record_type, BLKmode);
5822 relate_alias_sets (record_type, type, ALIAS_SET_COPY);
5826 /* Return the result of rounding T up to ALIGN. */
5828 static inline unsigned HOST_WIDE_INT
5829 round_up_to_align (unsigned HOST_WIDE_INT t, unsigned int align)
5837 /* TYPE is a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE that is being used
5838 as the field type of a packed record if IN_RECORD is true, or as the
5839 component type of a packed array if IN_RECORD is false. See if we can
5840 rewrite it either as a type that has a non-BLKmode, which we can pack
5841 tighter in the packed record case, or as a smaller type. If so, return
5842 the new type. If not, return the original type. */
5845 make_packable_type (tree type, bool in_record)
5847 unsigned HOST_WIDE_INT size = tree_low_cst (TYPE_SIZE (type), 1);
5848 unsigned HOST_WIDE_INT new_size;
5849 tree new_type, old_field, field_list = NULL_TREE;
5851 /* No point in doing anything if the size is zero. */
5855 new_type = make_node (TREE_CODE (type));
5857 /* Copy the name and flags from the old type to that of the new.
5858 Note that we rely on the pointer equality created here for
5859 TYPE_NAME to look through conversions in various places. */
5860 TYPE_NAME (new_type) = TYPE_NAME (type);
5861 TYPE_JUSTIFIED_MODULAR_P (new_type) = TYPE_JUSTIFIED_MODULAR_P (type);
5862 TYPE_CONTAINS_TEMPLATE_P (new_type) = TYPE_CONTAINS_TEMPLATE_P (type);
5863 if (TREE_CODE (type) == RECORD_TYPE)
5864 TYPE_IS_PADDING_P (new_type) = TYPE_IS_PADDING_P (type);
5866 /* If we are in a record and have a small size, set the alignment to
5867 try for an integral mode. Otherwise set it to try for a smaller
5868 type with BLKmode. */
5869 if (in_record && size <= MAX_FIXED_MODE_SIZE)
5871 TYPE_ALIGN (new_type) = ceil_alignment (size);
5872 new_size = round_up_to_align (size, TYPE_ALIGN (new_type));
5876 unsigned HOST_WIDE_INT align;
5878 /* Do not try to shrink the size if the RM size is not constant. */
5879 if (TYPE_CONTAINS_TEMPLATE_P (type)
5880 || !host_integerp (TYPE_ADA_SIZE (type), 1))
5883 /* Round the RM size up to a unit boundary to get the minimal size
5884 for a BLKmode record. Give up if it's already the size. */
5885 new_size = TREE_INT_CST_LOW (TYPE_ADA_SIZE (type));
5886 new_size = round_up_to_align (new_size, BITS_PER_UNIT);
5887 if (new_size == size)
5890 align = new_size & -new_size;
5891 TYPE_ALIGN (new_type) = MIN (TYPE_ALIGN (type), align);
5894 TYPE_USER_ALIGN (new_type) = 1;
5896 /* Now copy the fields, keeping the position and size as we don't want
5897 to change the layout by propagating the packedness downwards. */
5898 for (old_field = TYPE_FIELDS (type); old_field;
5899 old_field = TREE_CHAIN (old_field))
5901 tree new_field_type = TREE_TYPE (old_field);
5902 tree new_field, new_size;
5904 if ((TREE_CODE (new_field_type) == RECORD_TYPE
5905 || TREE_CODE (new_field_type) == UNION_TYPE
5906 || TREE_CODE (new_field_type) == QUAL_UNION_TYPE)
5907 && !TYPE_IS_FAT_POINTER_P (new_field_type)
5908 && host_integerp (TYPE_SIZE (new_field_type), 1))
5909 new_field_type = make_packable_type (new_field_type, true);
5911 /* However, for the last field in a not already packed record type
5912 that is of an aggregate type, we need to use the RM size in the
5913 packable version of the record type, see finish_record_type. */
5914 if (!TREE_CHAIN (old_field)
5915 && !TYPE_PACKED (type)
5916 && (TREE_CODE (new_field_type) == RECORD_TYPE
5917 || TREE_CODE (new_field_type) == UNION_TYPE
5918 || TREE_CODE (new_field_type) == QUAL_UNION_TYPE)
5919 && !TYPE_IS_FAT_POINTER_P (new_field_type)
5920 && !TYPE_CONTAINS_TEMPLATE_P (new_field_type)
5921 && TYPE_ADA_SIZE (new_field_type))
5922 new_size = TYPE_ADA_SIZE (new_field_type);
5924 new_size = DECL_SIZE (old_field);
5926 new_field = create_field_decl (DECL_NAME (old_field), new_field_type,
5927 new_type, TYPE_PACKED (type), new_size,
5928 bit_position (old_field),
5929 !DECL_NONADDRESSABLE_P (old_field));
5931 DECL_INTERNAL_P (new_field) = DECL_INTERNAL_P (old_field);
5932 SET_DECL_ORIGINAL_FIELD
5933 (new_field, (DECL_ORIGINAL_FIELD (old_field)
5934 ? DECL_ORIGINAL_FIELD (old_field) : old_field));
5936 if (TREE_CODE (new_type) == QUAL_UNION_TYPE)
5937 DECL_QUALIFIER (new_field) = DECL_QUALIFIER (old_field);
5939 TREE_CHAIN (new_field) = field_list;
5940 field_list = new_field;
5943 finish_record_type (new_type, nreverse (field_list), 2, true);
5944 relate_alias_sets (new_type, type, ALIAS_SET_COPY);
5946 /* If this is a padding record, we never want to make the size smaller
5947 than what was specified. For QUAL_UNION_TYPE, also copy the size. */
5948 if ((TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
5949 || TREE_CODE (type) == QUAL_UNION_TYPE)
5951 TYPE_SIZE (new_type) = TYPE_SIZE (type);
5952 TYPE_SIZE_UNIT (new_type) = TYPE_SIZE_UNIT (type);
5956 TYPE_SIZE (new_type) = bitsize_int (new_size);
5957 TYPE_SIZE_UNIT (new_type)
5958 = size_int ((new_size + BITS_PER_UNIT - 1) / BITS_PER_UNIT);
5961 if (!TYPE_CONTAINS_TEMPLATE_P (type))
5962 SET_TYPE_ADA_SIZE (new_type, TYPE_ADA_SIZE (type));
5964 compute_record_mode (new_type);
5966 /* Try harder to get a packable type if necessary, for example
5967 in case the record itself contains a BLKmode field. */
5968 if (in_record && TYPE_MODE (new_type) == BLKmode)
5969 SET_TYPE_MODE (new_type,
5970 mode_for_size_tree (TYPE_SIZE (new_type), MODE_INT, 1));
5972 /* If neither the mode nor the size has shrunk, return the old type. */
5973 if (TYPE_MODE (new_type) == BLKmode && new_size >= size)
5979 /* Ensure that TYPE has SIZE and ALIGN. Make and return a new padded type
5980 if needed. We have already verified that SIZE and TYPE are large enough.
5982 GNAT_ENTITY and NAME_TRAILER are used to name the resulting record and
5985 IS_USER_TYPE is true if we must complete the original type.
5987 DEFINITION is true if this type is being defined.
5989 SAME_RM_SIZE is true if the RM size of the resulting type is to be set
5990 to SIZE too; otherwise, it's set to the RM size of the original type. */
5993 maybe_pad_type (tree type, tree size, unsigned int align,
5994 Entity_Id gnat_entity, const char *name_trailer,
5995 bool is_user_type, bool definition, bool same_rm_size)
5997 tree orig_rm_size = same_rm_size ? NULL_TREE : rm_size (type);
5998 tree orig_size = TYPE_SIZE (type);
5999 unsigned int orig_align = align;
6002 /* If TYPE is a padded type, see if it agrees with any size and alignment
6003 we were given. If so, return the original type. Otherwise, strip
6004 off the padding, since we will either be returning the inner type
6005 or repadding it. If no size or alignment is specified, use that of
6006 the original padded type. */
6007 if (TREE_CODE (type) == RECORD_TYPE && TYPE_IS_PADDING_P (type))
6010 || operand_equal_p (round_up (size,
6011 MAX (align, TYPE_ALIGN (type))),
6012 round_up (TYPE_SIZE (type),
6013 MAX (align, TYPE_ALIGN (type))),
6015 && (align == 0 || align == TYPE_ALIGN (type)))
6019 size = TYPE_SIZE (type);
6021 align = TYPE_ALIGN (type);
6023 type = TREE_TYPE (TYPE_FIELDS (type));
6024 orig_size = TYPE_SIZE (type);
6027 /* If the size is either not being changed or is being made smaller (which
6028 is not done here and is only valid for bitfields anyway), show the size
6029 isn't changing. Likewise, clear the alignment if it isn't being
6030 changed. Then return if we aren't doing anything. */
6032 && (operand_equal_p (size, orig_size, 0)
6033 || (TREE_CODE (orig_size) == INTEGER_CST
6034 && tree_int_cst_lt (size, orig_size))))
6037 if (align == TYPE_ALIGN (type))
6040 if (align == 0 && !size)
6043 /* If requested, complete the original type and give it a name. */
6045 create_type_decl (get_entity_name (gnat_entity), type,
6046 NULL, !Comes_From_Source (gnat_entity),
6048 && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
6049 && DECL_IGNORED_P (TYPE_NAME (type))),
6052 /* We used to modify the record in place in some cases, but that could
6053 generate incorrect debugging information. So make a new record
6055 record = make_node (RECORD_TYPE);
6056 TYPE_IS_PADDING_P (record) = 1;
6058 if (Present (gnat_entity))
6059 TYPE_NAME (record) = create_concat_name (gnat_entity, name_trailer);
6061 TYPE_VOLATILE (record)
6062 = Present (gnat_entity) && Treat_As_Volatile (gnat_entity);
6064 TYPE_ALIGN (record) = align;
6066 TYPE_USER_ALIGN (record) = align;
6068 TYPE_SIZE (record) = size ? size : orig_size;
6069 TYPE_SIZE_UNIT (record)
6070 = convert (sizetype,
6071 size_binop (CEIL_DIV_EXPR, TYPE_SIZE (record),
6072 bitsize_unit_node));
6074 /* If we are changing the alignment and the input type is a record with
6075 BLKmode and a small constant size, try to make a form that has an
6076 integral mode. This might allow the padding record to also have an
6077 integral mode, which will be much more efficient. There is no point
6078 in doing so if a size is specified unless it is also a small constant
6079 size and it is incorrect to do so if we cannot guarantee that the mode
6080 will be naturally aligned since the field must always be addressable.
6082 ??? This might not always be a win when done for a stand-alone object:
6083 since the nominal and the effective type of the object will now have
6084 different modes, a VIEW_CONVERT_EXPR will be required for converting
6085 between them and it might be hard to overcome afterwards, including
6086 at the RTL level when the stand-alone object is accessed as a whole. */
6088 && TREE_CODE (type) == RECORD_TYPE
6089 && TYPE_MODE (type) == BLKmode
6090 && TREE_CODE (orig_size) == INTEGER_CST
6091 && !TREE_OVERFLOW (orig_size)
6092 && compare_tree_int (orig_size, MAX_FIXED_MODE_SIZE) <= 0
6094 || (TREE_CODE (size) == INTEGER_CST
6095 && compare_tree_int (size, MAX_FIXED_MODE_SIZE) <= 0)))
6097 tree packable_type = make_packable_type (type, true);
6098 if (TYPE_MODE (packable_type) != BLKmode
6099 && align >= TYPE_ALIGN (packable_type))
6100 type = packable_type;
6103 /* Now create the field with the original size. */
6104 field = create_field_decl (get_identifier ("F"), type, record, 0,
6105 orig_size, bitsize_zero_node, 1);
6106 DECL_INTERNAL_P (field) = 1;
6108 /* Do not finalize it until after the auxiliary record is built. */
6109 finish_record_type (record, field, 1, true);
6111 /* Set the same size for its RM size if requested; otherwise reuse
6112 the RM size of the original type. */
6113 SET_TYPE_ADA_SIZE (record, same_rm_size ? size : orig_rm_size);
6115 /* Unless debugging information isn't being written for the input type,
6116 write a record that shows what we are a subtype of and also make a
6117 variable that indicates our size, if still variable. */
6118 if (TYPE_NAME (record)
6119 && AGGREGATE_TYPE_P (type)
6120 && TREE_CODE (orig_size) != INTEGER_CST
6121 && !(TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
6122 && DECL_IGNORED_P (TYPE_NAME (type))))
6124 tree marker = make_node (RECORD_TYPE);
6125 tree name = TYPE_NAME (record);
6126 tree orig_name = TYPE_NAME (type);
6128 if (TREE_CODE (name) == TYPE_DECL)
6129 name = DECL_NAME (name);
6131 if (TREE_CODE (orig_name) == TYPE_DECL)
6132 orig_name = DECL_NAME (orig_name);
6134 TYPE_NAME (marker) = concat_name (name, "XVS");
6135 finish_record_type (marker,
6136 create_field_decl (orig_name, integer_type_node,
6137 marker, 0, NULL_TREE, NULL_TREE,
6141 add_parallel_type (TYPE_STUB_DECL (record), marker);
6143 if (size && TREE_CODE (size) != INTEGER_CST && definition)
6144 create_var_decl (concat_name (name, "XVZ"), NULL_TREE, sizetype,
6145 TYPE_SIZE_UNIT (record), false, false, false,
6146 false, NULL, gnat_entity);
6149 rest_of_record_type_compilation (record);
6151 /* If the size was widened explicitly, maybe give a warning. Take the
6152 original size as the maximum size of the input if there was an
6153 unconstrained record involved and round it up to the specified alignment,
6154 if one was specified. */
6155 if (CONTAINS_PLACEHOLDER_P (orig_size))
6156 orig_size = max_size (orig_size, true);
6159 orig_size = round_up (orig_size, align);
6161 if (size && Present (gnat_entity)
6162 && !operand_equal_p (size, orig_size, 0)
6163 && !(TREE_CODE (size) == INTEGER_CST
6164 && TREE_CODE (orig_size) == INTEGER_CST
6165 && tree_int_cst_lt (size, orig_size)))
6167 Node_Id gnat_error_node = Empty;
6169 if (Is_Packed_Array_Type (gnat_entity))
6170 gnat_entity = Original_Array_Type (gnat_entity);
6172 if ((Ekind (gnat_entity) == E_Component
6173 || Ekind (gnat_entity) == E_Discriminant)
6174 && Present (Component_Clause (gnat_entity)))
6175 gnat_error_node = Last_Bit (Component_Clause (gnat_entity));
6176 else if (Present (Size_Clause (gnat_entity)))
6177 gnat_error_node = Expression (Size_Clause (gnat_entity));
6179 /* Generate message only for entities that come from source, since
6180 if we have an entity created by expansion, the message will be
6181 generated for some other corresponding source entity. */
6182 if (Comes_From_Source (gnat_entity) && Present (gnat_error_node))
6183 post_error_ne_tree ("{^ }bits of & unused?", gnat_error_node,
6185 size_diffop (size, orig_size));
6187 else if (*name_trailer == 'C' && !Is_Internal (gnat_entity))
6188 post_error_ne_tree ("component of& padded{ by ^ bits}?",
6189 gnat_entity, gnat_entity,
6190 size_diffop (size, orig_size));
6196 /* Given a GNU tree and a GNAT list of choices, generate an expression to test
6197 the value passed against the list of choices. */
6200 choices_to_gnu (tree operand, Node_Id choices)
6204 tree result = integer_zero_node;
6205 tree this_test, low = 0, high = 0, single = 0;
6207 for (choice = First (choices); Present (choice); choice = Next (choice))
6209 switch (Nkind (choice))
6212 low = gnat_to_gnu (Low_Bound (choice));
6213 high = gnat_to_gnu (High_Bound (choice));
6215 /* There's no good type to use here, so we might as well use
6216 integer_type_node. */
6218 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6219 build_binary_op (GE_EXPR, integer_type_node,
6221 build_binary_op (LE_EXPR, integer_type_node,
6226 case N_Subtype_Indication:
6227 gnat_temp = Range_Expression (Constraint (choice));
6228 low = gnat_to_gnu (Low_Bound (gnat_temp));
6229 high = gnat_to_gnu (High_Bound (gnat_temp));
6232 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6233 build_binary_op (GE_EXPR, integer_type_node,
6235 build_binary_op (LE_EXPR, integer_type_node,
6240 case N_Expanded_Name:
6241 /* This represents either a subtype range, an enumeration
6242 literal, or a constant Ekind says which. If an enumeration
6243 literal or constant, fall through to the next case. */
6244 if (Ekind (Entity (choice)) != E_Enumeration_Literal
6245 && Ekind (Entity (choice)) != E_Constant)
6247 tree type = gnat_to_gnu_type (Entity (choice));
6249 low = TYPE_MIN_VALUE (type);
6250 high = TYPE_MAX_VALUE (type);
6253 = build_binary_op (TRUTH_ANDIF_EXPR, integer_type_node,
6254 build_binary_op (GE_EXPR, integer_type_node,
6256 build_binary_op (LE_EXPR, integer_type_node,
6261 /* ... fall through ... */
6263 case N_Character_Literal:
6264 case N_Integer_Literal:
6265 single = gnat_to_gnu (choice);
6266 this_test = build_binary_op (EQ_EXPR, integer_type_node, operand,
6270 case N_Others_Choice:
6271 this_test = integer_one_node;
6278 result = build_binary_op (TRUTH_ORIF_EXPR, integer_type_node,
6285 /* Adjust PACKED setting as passed to gnat_to_gnu_field for a field of
6286 type FIELD_TYPE to be placed in RECORD_TYPE. Return the result. */
6289 adjust_packed (tree field_type, tree record_type, int packed)
6291 /* If the field contains an item of variable size, we cannot pack it
6292 because we cannot create temporaries of non-fixed size in case
6293 we need to take the address of the field. See addressable_p and
6294 the notes on the addressability issues for further details. */
6295 if (is_variable_size (field_type))
6298 /* If the alignment of the record is specified and the field type
6299 is over-aligned, request Storage_Unit alignment for the field. */
6302 if (TYPE_ALIGN (field_type) > TYPE_ALIGN (record_type))
6311 /* Return a GCC tree for a field corresponding to GNAT_FIELD to be
6312 placed in GNU_RECORD_TYPE.
6314 PACKED is 1 if the enclosing record is packed, -1 if the enclosing
6315 record has Component_Alignment of Storage_Unit, -2 if the enclosing
6316 record has a specified alignment.
6318 DEFINITION is true if this field is for a record being defined. */
6321 gnat_to_gnu_field (Entity_Id gnat_field, tree gnu_record_type, int packed,
6324 tree gnu_field_id = get_entity_name (gnat_field);
6325 tree gnu_field_type = gnat_to_gnu_type (Etype (gnat_field));
6326 tree gnu_field, gnu_size, gnu_pos;
6327 bool needs_strict_alignment
6328 = (Is_Aliased (gnat_field) || Strict_Alignment (Etype (gnat_field))
6329 || Treat_As_Volatile (gnat_field));
6331 /* If this field requires strict alignment, we cannot pack it because
6332 it would very likely be under-aligned in the record. */
6333 if (needs_strict_alignment)
6336 packed = adjust_packed (gnu_field_type, gnu_record_type, packed);
6338 /* If a size is specified, use it. Otherwise, if the record type is packed,
6339 use the official RM size. See "Handling of Type'Size Values" in Einfo
6340 for further details. */
6341 if (Known_Static_Esize (gnat_field))
6342 gnu_size = validate_size (Esize (gnat_field), gnu_field_type,
6343 gnat_field, FIELD_DECL, false, true);
6344 else if (packed == 1)
6345 gnu_size = validate_size (RM_Size (Etype (gnat_field)), gnu_field_type,
6346 gnat_field, FIELD_DECL, false, true);
6348 gnu_size = NULL_TREE;
6350 /* If we have a specified size that's smaller than that of the field type,
6351 or a position is specified, and the field type is a record, see if we can
6352 get either an integral mode form of the type or a smaller form. If we
6353 can, show a size was specified for the field if there wasn't one already,
6354 so we know to make this a bitfield and avoid making things wider.
6356 Doing this is first useful if the record is packed because we may then
6357 place the field at a non-byte-aligned position and so achieve tighter
6360 This is in addition *required* if the field shares a byte with another
6361 field and the front-end lets the back-end handle the references, because
6362 GCC does not handle BLKmode bitfields properly.
6364 We avoid the transformation if it is not required or potentially useful,
6365 as it might entail an increase of the field's alignment and have ripple
6366 effects on the outer record type. A typical case is a field known to be
6367 byte aligned and not to share a byte with another field.
6369 Besides, we don't even look the possibility of a transformation in cases
6370 known to be in error already, for instance when an invalid size results
6371 from a component clause. */
6373 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
6374 && !TYPE_IS_FAT_POINTER_P (gnu_field_type)
6375 && host_integerp (TYPE_SIZE (gnu_field_type), 1)
6378 && (tree_int_cst_lt (gnu_size, TYPE_SIZE (gnu_field_type))
6379 || Present (Component_Clause (gnat_field))))))
6381 /* See what the alternate type and size would be. */
6382 tree gnu_packable_type = make_packable_type (gnu_field_type, true);
6384 bool has_byte_aligned_clause
6385 = Present (Component_Clause (gnat_field))
6386 && (UI_To_Int (Component_Bit_Offset (gnat_field))
6387 % BITS_PER_UNIT == 0);
6389 /* Compute whether we should avoid the substitution. */
6391 /* There is no point substituting if there is no change... */
6392 = (gnu_packable_type == gnu_field_type)
6393 /* ... nor when the field is known to be byte aligned and not to
6394 share a byte with another field. */
6395 || (has_byte_aligned_clause
6396 && value_factor_p (gnu_size, BITS_PER_UNIT))
6397 /* The size of an aliased field must be an exact multiple of the
6398 type's alignment, which the substitution might increase. Reject
6399 substitutions that would so invalidate a component clause when the
6400 specified position is byte aligned, as the change would have no
6401 real benefit from the packing standpoint anyway. */
6402 || (Is_Aliased (gnat_field)
6403 && has_byte_aligned_clause
6404 && !value_factor_p (gnu_size, TYPE_ALIGN (gnu_packable_type)));
6406 /* Substitute unless told otherwise. */
6409 gnu_field_type = gnu_packable_type;
6412 gnu_size = rm_size (gnu_field_type);
6416 /* If we are packing the record and the field is BLKmode, round the
6417 size up to a byte boundary. */
6418 if (packed && TYPE_MODE (gnu_field_type) == BLKmode && gnu_size)
6419 gnu_size = round_up (gnu_size, BITS_PER_UNIT);
6421 if (Present (Component_Clause (gnat_field)))
6423 gnu_pos = UI_To_gnu (Component_Bit_Offset (gnat_field), bitsizetype);
6424 gnu_size = validate_size (Esize (gnat_field), gnu_field_type,
6425 gnat_field, FIELD_DECL, false, true);
6427 /* Ensure the position does not overlap with the parent subtype,
6429 if (Present (Parent_Subtype (Underlying_Type (Scope (gnat_field)))))
6432 = gnat_to_gnu_type (Parent_Subtype
6433 (Underlying_Type (Scope (gnat_field))));
6435 if (TREE_CODE (TYPE_SIZE (gnu_parent)) == INTEGER_CST
6436 && tree_int_cst_lt (gnu_pos, TYPE_SIZE (gnu_parent)))
6439 ("offset of& must be beyond parent{, minimum allowed is ^}",
6440 First_Bit (Component_Clause (gnat_field)), gnat_field,
6441 TYPE_SIZE_UNIT (gnu_parent));
6445 /* If this field needs strict alignment, ensure the record is
6446 sufficiently aligned and that that position and size are
6447 consistent with the alignment. */
6448 if (needs_strict_alignment)
6450 TYPE_ALIGN (gnu_record_type)
6451 = MAX (TYPE_ALIGN (gnu_record_type), TYPE_ALIGN (gnu_field_type));
6454 && !operand_equal_p (gnu_size, TYPE_SIZE (gnu_field_type), 0))
6456 if (Is_Atomic (gnat_field) || Is_Atomic (Etype (gnat_field)))
6458 ("atomic field& must be natural size of type{ (^)}",
6459 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6460 TYPE_SIZE (gnu_field_type));
6462 else if (Is_Aliased (gnat_field))
6464 ("size of aliased field& must be ^ bits",
6465 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6466 TYPE_SIZE (gnu_field_type));
6468 else if (Strict_Alignment (Etype (gnat_field)))
6470 ("size of & with aliased or tagged components not ^ bits",
6471 Last_Bit (Component_Clause (gnat_field)), gnat_field,
6472 TYPE_SIZE (gnu_field_type));
6474 gnu_size = NULL_TREE;
6477 if (!integer_zerop (size_binop
6478 (TRUNC_MOD_EXPR, gnu_pos,
6479 bitsize_int (TYPE_ALIGN (gnu_field_type)))))
6481 if (Is_Aliased (gnat_field))
6483 ("position of aliased field& must be multiple of ^ bits",
6484 First_Bit (Component_Clause (gnat_field)), gnat_field,
6485 TYPE_ALIGN (gnu_field_type));
6487 else if (Treat_As_Volatile (gnat_field))
6489 ("position of volatile field& must be multiple of ^ bits",
6490 First_Bit (Component_Clause (gnat_field)), gnat_field,
6491 TYPE_ALIGN (gnu_field_type));
6493 else if (Strict_Alignment (Etype (gnat_field)))
6495 ("position of & with aliased or tagged components not multiple of ^ bits",
6496 First_Bit (Component_Clause (gnat_field)), gnat_field,
6497 TYPE_ALIGN (gnu_field_type));
6502 gnu_pos = NULL_TREE;
6506 if (Is_Atomic (gnat_field))
6507 check_ok_for_atomic (gnu_field_type, gnat_field, false);
6510 /* If the record has rep clauses and this is the tag field, make a rep
6511 clause for it as well. */
6512 else if (Has_Specified_Layout (Scope (gnat_field))
6513 && Chars (gnat_field) == Name_uTag)
6515 gnu_pos = bitsize_zero_node;
6516 gnu_size = TYPE_SIZE (gnu_field_type);
6520 gnu_pos = NULL_TREE;
6522 /* We need to make the size the maximum for the type if it is
6523 self-referential and an unconstrained type. In that case, we can't
6524 pack the field since we can't make a copy to align it. */
6525 if (TREE_CODE (gnu_field_type) == RECORD_TYPE
6527 && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_field_type))
6528 && !Is_Constrained (Underlying_Type (Etype (gnat_field))))
6530 gnu_size = max_size (TYPE_SIZE (gnu_field_type), true);
6534 /* If a size is specified, adjust the field's type to it. */
6537 /* If the field's type is justified modular, we would need to remove
6538 the wrapper to (better) meet the layout requirements. However we
6539 can do so only if the field is not aliased to preserve the unique
6540 layout and if the prescribed size is not greater than that of the
6541 packed array to preserve the justification. */
6542 if (!needs_strict_alignment
6543 && TREE_CODE (gnu_field_type) == RECORD_TYPE
6544 && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type)
6545 && tree_int_cst_compare (gnu_size, TYPE_ADA_SIZE (gnu_field_type))
6547 gnu_field_type = TREE_TYPE (TYPE_FIELDS (gnu_field_type));
6550 = make_type_from_size (gnu_field_type, gnu_size,
6551 Has_Biased_Representation (gnat_field));
6552 gnu_field_type = maybe_pad_type (gnu_field_type, gnu_size, 0, gnat_field,
6553 "PAD", false, definition, true);
6556 /* Otherwise (or if there was an error), don't specify a position. */
6558 gnu_pos = NULL_TREE;
6560 gcc_assert (TREE_CODE (gnu_field_type) != RECORD_TYPE
6561 || !TYPE_CONTAINS_TEMPLATE_P (gnu_field_type));
6563 /* Now create the decl for the field. */
6564 gnu_field = create_field_decl (gnu_field_id, gnu_field_type, gnu_record_type,
6565 packed, gnu_size, gnu_pos,
6566 Is_Aliased (gnat_field));
6567 Sloc_to_locus (Sloc (gnat_field), &DECL_SOURCE_LOCATION (gnu_field));
6568 TREE_THIS_VOLATILE (gnu_field) = Treat_As_Volatile (gnat_field);
6570 if (Ekind (gnat_field) == E_Discriminant)
6571 DECL_DISCRIMINANT_NUMBER (gnu_field)
6572 = UI_To_gnu (Discriminant_Number (gnat_field), sizetype);
6577 /* Return true if TYPE is a type with variable size, a padding type with a
6578 field of variable size or is a record that has a field such a field. */
6581 is_variable_size (tree type)
6585 if (!TREE_CONSTANT (TYPE_SIZE (type)))
6588 if (TREE_CODE (type) == RECORD_TYPE
6589 && TYPE_IS_PADDING_P (type)
6590 && !TREE_CONSTANT (DECL_SIZE (TYPE_FIELDS (type))))
6593 if (TREE_CODE (type) != RECORD_TYPE
6594 && TREE_CODE (type) != UNION_TYPE
6595 && TREE_CODE (type) != QUAL_UNION_TYPE)
6598 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
6599 if (is_variable_size (TREE_TYPE (field)))
6605 /* qsort comparer for the bit positions of two record components. */
6608 compare_field_bitpos (const PTR rt1, const PTR rt2)
6610 const_tree const field1 = * (const_tree const *) rt1;
6611 const_tree const field2 = * (const_tree const *) rt2;
6613 = tree_int_cst_compare (bit_position (field1), bit_position (field2));
6615 return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2));
6618 /* Return a GCC tree for a record type given a GNAT Component_List and a chain
6619 of GCC trees for fields that are in the record and have already been
6620 processed. When called from gnat_to_gnu_entity during the processing of a
6621 record type definition, the GCC nodes for the discriminants will be on
6622 the chain. The other calls to this function are recursive calls from
6623 itself for the Component_List of a variant and the chain is empty.
6625 PACKED is 1 if this is for a packed record, -1 if this is for a record
6626 with Component_Alignment of Storage_Unit, -2 if this is for a record
6627 with a specified alignment.
6629 DEFINITION is true if we are defining this record.
6631 P_GNU_REP_LIST, if nonzero, is a pointer to a list to which each field
6632 with a rep clause is to be added. If it is nonzero, that is all that
6633 should be done with such fields.
6635 CANCEL_ALIGNMENT, if true, means the alignment should be zeroed before
6636 laying out the record. This means the alignment only serves to force fields
6637 to be bitfields, but not require the record to be that aligned. This is
6640 ALL_REP, if true, means a rep clause was found for all the fields. This
6641 simplifies the logic since we know we're not in the mixed case.
6643 DO_NOT_FINALIZE, if true, means that the record type is expected to be
6644 modified afterwards so it will not be sent to the back-end for finalization.
6646 UNCHECKED_UNION, if true, means that we are building a type for a record
6647 with a Pragma Unchecked_Union.
6649 The processing of the component list fills in the chain with all of the
6650 fields of the record and then the record type is finished. */
6653 components_to_record (tree gnu_record_type, Node_Id component_list,
6654 tree gnu_field_list, int packed, bool definition,
6655 tree *p_gnu_rep_list, bool cancel_alignment,
6656 bool all_rep, bool do_not_finalize, bool unchecked_union)
6658 Node_Id component_decl;
6659 Entity_Id gnat_field;
6660 Node_Id variant_part;
6661 tree gnu_our_rep_list = NULL_TREE;
6662 tree gnu_field, gnu_last;
6663 bool layout_with_rep = false;
6664 bool all_rep_and_size = all_rep && TYPE_SIZE (gnu_record_type);
6666 /* For each variable within each component declaration create a GCC field
6667 and add it to the list, skipping any pragmas in the list. */
6668 if (Present (Component_Items (component_list)))
6669 for (component_decl = First_Non_Pragma (Component_Items (component_list));
6670 Present (component_decl);
6671 component_decl = Next_Non_Pragma (component_decl))
6673 gnat_field = Defining_Entity (component_decl);
6675 if (Chars (gnat_field) == Name_uParent)
6676 gnu_field = tree_last (TYPE_FIELDS (gnu_record_type));
6679 gnu_field = gnat_to_gnu_field (gnat_field, gnu_record_type,
6680 packed, definition);
6682 /* If this is the _Tag field, put it before any discriminants,
6683 instead of after them as is the case for all other fields. */
6684 if (Chars (gnat_field) == Name_uTag)
6685 gnu_field_list = chainon (gnu_field_list, gnu_field);
6688 TREE_CHAIN (gnu_field) = gnu_field_list;
6689 gnu_field_list = gnu_field;
6693 save_gnu_tree (gnat_field, gnu_field, false);
6696 /* At the end of the component list there may be a variant part. */
6697 variant_part = Variant_Part (component_list);
6699 /* We create a QUAL_UNION_TYPE for the variant part since the variants are
6700 mutually exclusive and should go in the same memory. To do this we need
6701 to treat each variant as a record whose elements are created from the
6702 component list for the variant. So here we create the records from the
6703 lists for the variants and put them all into the QUAL_UNION_TYPE.
6704 If this is an Unchecked_Union, we make a UNION_TYPE instead or
6705 use GNU_RECORD_TYPE if there are no fields so far. */
6706 if (Present (variant_part))
6708 Node_Id gnat_discr = Name (variant_part), variant;
6709 tree gnu_discr = gnat_to_gnu (gnat_discr);
6710 tree gnu_name = TYPE_NAME (gnu_record_type);
6712 = concat_name (get_identifier (Get_Name_String (Chars (gnat_discr))),
6714 tree gnu_union_type, gnu_union_name, gnu_union_field;
6715 tree gnu_variant_list = NULL_TREE;
6717 if (TREE_CODE (gnu_name) == TYPE_DECL)
6718 gnu_name = DECL_NAME (gnu_name);
6721 = concat_name (gnu_name, IDENTIFIER_POINTER (gnu_var_name));
6723 /* Reuse an enclosing union if all fields are in the variant part
6724 and there is no representation clause on the record, to match
6725 the layout of C unions. There is an associated check below. */
6727 && TREE_CODE (gnu_record_type) == UNION_TYPE
6728 && !TYPE_PACKED (gnu_record_type))
6729 gnu_union_type = gnu_record_type;
6733 = make_node (unchecked_union ? UNION_TYPE : QUAL_UNION_TYPE);
6735 TYPE_NAME (gnu_union_type) = gnu_union_name;
6736 TYPE_ALIGN (gnu_union_type) = 0;
6737 TYPE_PACKED (gnu_union_type) = TYPE_PACKED (gnu_record_type);
6740 for (variant = First_Non_Pragma (Variants (variant_part));
6742 variant = Next_Non_Pragma (variant))
6744 tree gnu_variant_type = make_node (RECORD_TYPE);
6745 tree gnu_inner_name;
6748 Get_Variant_Encoding (variant);
6749 gnu_inner_name = get_identifier_with_length (Name_Buffer, Name_Len);
6750 TYPE_NAME (gnu_variant_type)
6751 = concat_name (gnu_union_name,
6752 IDENTIFIER_POINTER (gnu_inner_name));
6754 /* Set the alignment of the inner type in case we need to make
6755 inner objects into bitfields, but then clear it out
6756 so the record actually gets only the alignment required. */
6757 TYPE_ALIGN (gnu_variant_type) = TYPE_ALIGN (gnu_record_type);
6758 TYPE_PACKED (gnu_variant_type) = TYPE_PACKED (gnu_record_type);
6760 /* Similarly, if the outer record has a size specified and all fields
6761 have record rep clauses, we can propagate the size into the
6763 if (all_rep_and_size)
6765 TYPE_SIZE (gnu_variant_type) = TYPE_SIZE (gnu_record_type);
6766 TYPE_SIZE_UNIT (gnu_variant_type)
6767 = TYPE_SIZE_UNIT (gnu_record_type);
6770 /* Create the record type for the variant. Note that we defer
6771 finalizing it until after we are sure to actually use it. */
6772 components_to_record (gnu_variant_type, Component_List (variant),
6773 NULL_TREE, packed, definition,
6774 &gnu_our_rep_list, !all_rep_and_size, all_rep,
6775 true, unchecked_union);
6777 gnu_qual = choices_to_gnu (gnu_discr, Discrete_Choices (variant));
6779 Set_Present_Expr (variant, annotate_value (gnu_qual));
6781 /* If this is an Unchecked_Union and we have exactly one field,
6782 use this field directly to match the layout of C unions. */
6784 && TYPE_FIELDS (gnu_variant_type)
6785 && !TREE_CHAIN (TYPE_FIELDS (gnu_variant_type)))
6786 gnu_field = TYPE_FIELDS (gnu_variant_type);
6789 /* Deal with packedness like in gnat_to_gnu_field. */
6791 = adjust_packed (gnu_variant_type, gnu_record_type, packed);
6793 /* Finalize the record type now. We used to throw away
6794 empty records but we no longer do that because we need
6795 them to generate complete debug info for the variant;
6796 otherwise, the union type definition will be lacking
6797 the fields associated with these empty variants. */
6798 rest_of_record_type_compilation (gnu_variant_type);
6800 gnu_field = create_field_decl (gnu_inner_name, gnu_variant_type,
6801 gnu_union_type, field_packed,
6803 ? TYPE_SIZE (gnu_variant_type)
6806 ? bitsize_zero_node : 0),
6809 DECL_INTERNAL_P (gnu_field) = 1;
6811 if (!unchecked_union)
6812 DECL_QUALIFIER (gnu_field) = gnu_qual;
6815 TREE_CHAIN (gnu_field) = gnu_variant_list;
6816 gnu_variant_list = gnu_field;
6819 /* Only make the QUAL_UNION_TYPE if there are any non-empty variants. */
6820 if (gnu_variant_list)
6822 int union_field_packed;
6824 if (all_rep_and_size)
6826 TYPE_SIZE (gnu_union_type) = TYPE_SIZE (gnu_record_type);
6827 TYPE_SIZE_UNIT (gnu_union_type)
6828 = TYPE_SIZE_UNIT (gnu_record_type);
6831 finish_record_type (gnu_union_type, nreverse (gnu_variant_list),
6832 all_rep_and_size ? 1 : 0, false);
6834 /* If GNU_UNION_TYPE is our record type, it means we must have an
6835 Unchecked_Union with no fields. Verify that and, if so, just
6837 if (gnu_union_type == gnu_record_type)
6839 gcc_assert (unchecked_union
6841 && !gnu_our_rep_list);
6845 /* Deal with packedness like in gnat_to_gnu_field. */
6847 = adjust_packed (gnu_union_type, gnu_record_type, packed);
6850 = create_field_decl (gnu_var_name, gnu_union_type, gnu_record_type,
6852 all_rep ? TYPE_SIZE (gnu_union_type) : 0,
6853 all_rep ? bitsize_zero_node : 0, 0);
6855 DECL_INTERNAL_P (gnu_union_field) = 1;
6856 TREE_CHAIN (gnu_union_field) = gnu_field_list;
6857 gnu_field_list = gnu_union_field;
6861 /* Scan GNU_FIELD_LIST and see if any fields have rep clauses. If they
6862 do, pull them out and put them into GNU_OUR_REP_LIST. We have to do this
6863 in a separate pass since we want to handle the discriminants but can't
6864 play with them until we've used them in debugging data above.
6866 ??? Note: if we then reorder them, debugging information will be wrong,
6867 but there's nothing that can be done about this at the moment. */
6868 for (gnu_field = gnu_field_list, gnu_last = NULL_TREE; gnu_field; )
6870 if (DECL_FIELD_OFFSET (gnu_field))
6872 tree gnu_next = TREE_CHAIN (gnu_field);
6875 gnu_field_list = gnu_next;
6877 TREE_CHAIN (gnu_last) = gnu_next;
6879 TREE_CHAIN (gnu_field) = gnu_our_rep_list;
6880 gnu_our_rep_list = gnu_field;
6881 gnu_field = gnu_next;
6885 gnu_last = gnu_field;
6886 gnu_field = TREE_CHAIN (gnu_field);
6890 /* If we have any items in our rep'ed field list, it is not the case that all
6891 the fields in the record have rep clauses, and P_REP_LIST is nonzero,
6892 set it and ignore the items. */
6893 if (gnu_our_rep_list && p_gnu_rep_list && !all_rep)
6894 *p_gnu_rep_list = chainon (*p_gnu_rep_list, gnu_our_rep_list);
6895 else if (gnu_our_rep_list)
6897 /* Otherwise, sort the fields by bit position and put them into their
6898 own record if we have any fields without rep clauses. */
6900 = (gnu_field_list ? make_node (RECORD_TYPE) : gnu_record_type);
6901 int len = list_length (gnu_our_rep_list);
6902 tree *gnu_arr = (tree *) alloca (sizeof (tree) * len);
6905 for (i = 0, gnu_field = gnu_our_rep_list; gnu_field;
6906 gnu_field = TREE_CHAIN (gnu_field), i++)
6907 gnu_arr[i] = gnu_field;
6909 qsort (gnu_arr, len, sizeof (tree), compare_field_bitpos);
6911 /* Put the fields in the list in order of increasing position, which
6912 means we start from the end. */
6913 gnu_our_rep_list = NULL_TREE;
6914 for (i = len - 1; i >= 0; i--)
6916 TREE_CHAIN (gnu_arr[i]) = gnu_our_rep_list;
6917 gnu_our_rep_list = gnu_arr[i];
6918 DECL_CONTEXT (gnu_arr[i]) = gnu_rep_type;
6923 finish_record_type (gnu_rep_type, gnu_our_rep_list, 1, false);
6924 gnu_field = create_field_decl (get_identifier ("REP"), gnu_rep_type,
6925 gnu_record_type, 0, 0, 0, 1);
6926 DECL_INTERNAL_P (gnu_field) = 1;
6927 gnu_field_list = chainon (gnu_field_list, gnu_field);
6931 layout_with_rep = true;
6932 gnu_field_list = nreverse (gnu_our_rep_list);
6936 if (cancel_alignment)
6937 TYPE_ALIGN (gnu_record_type) = 0;
6939 finish_record_type (gnu_record_type, nreverse (gnu_field_list),
6940 layout_with_rep ? 1 : 0, do_not_finalize);
6943 /* Given GNU_SIZE, a GCC tree representing a size, return a Uint to be
6944 placed into an Esize, Component_Bit_Offset, or Component_Size value
6945 in the GNAT tree. */
6948 annotate_value (tree gnu_size)
6950 int len = TREE_CODE_LENGTH (TREE_CODE (gnu_size));
6952 Node_Ref_Or_Val ops[3], ret;
6955 struct tree_int_map **h = NULL;
6957 /* See if we've already saved the value for this node. */
6958 if (EXPR_P (gnu_size))
6960 struct tree_int_map in;
6961 if (!annotate_value_cache)
6962 annotate_value_cache = htab_create_ggc (512, tree_int_map_hash,
6963 tree_int_map_eq, 0);
6964 in.base.from = gnu_size;
6965 h = (struct tree_int_map **)
6966 htab_find_slot (annotate_value_cache, &in, INSERT);
6969 return (Node_Ref_Or_Val) (*h)->to;
6972 /* If we do not return inside this switch, TCODE will be set to the
6973 code to use for a Create_Node operand and LEN (set above) will be
6974 the number of recursive calls for us to make. */
6976 switch (TREE_CODE (gnu_size))
6979 if (TREE_OVERFLOW (gnu_size))
6982 /* This may have come from a conversion from some smaller type,
6983 so ensure this is in bitsizetype. */
6984 gnu_size = convert (bitsizetype, gnu_size);
6986 /* For negative values, use NEGATE_EXPR of the supplied value. */
6987 if (tree_int_cst_sgn (gnu_size) < 0)
6989 /* The ridiculous code below is to handle the case of the largest
6990 negative integer. */
6991 tree negative_size = size_diffop (bitsize_zero_node, gnu_size);
6992 bool adjust = false;
6995 if (TREE_OVERFLOW (negative_size))
6998 = size_binop (MINUS_EXPR, bitsize_zero_node,
6999 size_binop (PLUS_EXPR, gnu_size,
7004 temp = build1 (NEGATE_EXPR, bitsizetype, negative_size);
7006 temp = build2 (MINUS_EXPR, bitsizetype, temp, bitsize_one_node);
7008 return annotate_value (temp);
7011 if (!host_integerp (gnu_size, 1))
7014 size = tree_low_cst (gnu_size, 1);
7016 /* This peculiar test is to make sure that the size fits in an int
7017 on machines where HOST_WIDE_INT is not "int". */
7018 if (tree_low_cst (gnu_size, 1) == size)
7019 return UI_From_Int (size);
7024 /* The only case we handle here is a simple discriminant reference. */
7025 if (TREE_CODE (TREE_OPERAND (gnu_size, 0)) == PLACEHOLDER_EXPR
7026 && TREE_CODE (TREE_OPERAND (gnu_size, 1)) == FIELD_DECL
7027 && DECL_DISCRIMINANT_NUMBER (TREE_OPERAND (gnu_size, 1)))
7028 return Create_Node (Discrim_Val,
7029 annotate_value (DECL_DISCRIMINANT_NUMBER
7030 (TREE_OPERAND (gnu_size, 1))),
7035 CASE_CONVERT: case NON_LVALUE_EXPR:
7036 return annotate_value (TREE_OPERAND (gnu_size, 0));
7038 /* Now just list the operations we handle. */
7039 case COND_EXPR: tcode = Cond_Expr; break;
7040 case PLUS_EXPR: tcode = Plus_Expr; break;
7041 case MINUS_EXPR: tcode = Minus_Expr; break;
7042 case MULT_EXPR: tcode = Mult_Expr; break;
7043 case TRUNC_DIV_EXPR: tcode = Trunc_Div_Expr; break;
7044 case CEIL_DIV_EXPR: tcode = Ceil_Div_Expr; break;
7045 case FLOOR_DIV_EXPR: tcode = Floor_Div_Expr; break;
7046 case TRUNC_MOD_EXPR: tcode = Trunc_Mod_Expr; break;
7047 case CEIL_MOD_EXPR: tcode = Ceil_Mod_Expr; break;
7048 case FLOOR_MOD_EXPR: tcode = Floor_Mod_Expr; break;
7049 case EXACT_DIV_EXPR: tcode = Exact_Div_Expr; break;
7050 case NEGATE_EXPR: tcode = Negate_Expr; break;
7051 case MIN_EXPR: tcode = Min_Expr; break;
7052 case MAX_EXPR: tcode = Max_Expr; break;
7053 case ABS_EXPR: tcode = Abs_Expr; break;
7054 case TRUTH_ANDIF_EXPR: tcode = Truth_Andif_Expr; break;
7055 case TRUTH_ORIF_EXPR: tcode = Truth_Orif_Expr; break;
7056 case TRUTH_AND_EXPR: tcode = Truth_And_Expr; break;
7057 case TRUTH_OR_EXPR: tcode = Truth_Or_Expr; break;
7058 case TRUTH_XOR_EXPR: tcode = Truth_Xor_Expr; break;
7059 case TRUTH_NOT_EXPR: tcode = Truth_Not_Expr; break;
7060 case BIT_AND_EXPR: tcode = Bit_And_Expr; break;
7061 case LT_EXPR: tcode = Lt_Expr; break;
7062 case LE_EXPR: tcode = Le_Expr; break;
7063 case GT_EXPR: tcode = Gt_Expr; break;
7064 case GE_EXPR: tcode = Ge_Expr; break;
7065 case EQ_EXPR: tcode = Eq_Expr; break;
7066 case NE_EXPR: tcode = Ne_Expr; break;
7072 /* Now get each of the operands that's relevant for this code. If any
7073 cannot be expressed as a repinfo node, say we can't. */
7074 for (i = 0; i < 3; i++)
7077 for (i = 0; i < len; i++)
7079 ops[i] = annotate_value (TREE_OPERAND (gnu_size, i));
7080 if (ops[i] == No_Uint)
7084 ret = Create_Node (tcode, ops[0], ops[1], ops[2]);
7086 /* Save the result in the cache. */
7089 *h = GGC_NEW (struct tree_int_map);
7090 (*h)->base.from = gnu_size;
7097 /* Given GNAT_ENTITY, a record type, and GNU_TYPE, its corresponding
7098 GCC type, set Component_Bit_Offset and Esize to the position and size
7102 annotate_rep (Entity_Id gnat_entity, tree gnu_type)
7106 Entity_Id gnat_field;
7108 /* We operate by first making a list of all fields and their positions
7109 (we can get the sizes easily at any time) by a recursive call
7110 and then update all the sizes into the tree. */
7111 gnu_list = compute_field_positions (gnu_type, NULL_TREE,
7112 size_zero_node, bitsize_zero_node,
7115 for (gnat_field = First_Entity (gnat_entity); Present (gnat_field);
7116 gnat_field = Next_Entity (gnat_field))
7117 if ((Ekind (gnat_field) == E_Component
7118 || (Ekind (gnat_field) == E_Discriminant
7119 && !Is_Unchecked_Union (Scope (gnat_field)))))
7121 tree parent_offset = bitsize_zero_node;
7123 gnu_entry = purpose_member (gnat_to_gnu_field_decl (gnat_field),
7128 if (type_annotate_only && Is_Tagged_Type (gnat_entity))
7130 /* In this mode the tag and parent components have not been
7131 generated, so we add the appropriate offset to each
7132 component. For a component appearing in the current
7133 extension, the offset is the size of the parent. */
7134 if (Is_Derived_Type (gnat_entity)
7135 && Original_Record_Component (gnat_field) == gnat_field)
7137 = UI_To_gnu (Esize (Etype (Base_Type (gnat_entity))),
7140 parent_offset = bitsize_int (POINTER_SIZE);
7143 Set_Component_Bit_Offset
7146 (size_binop (PLUS_EXPR,
7147 bit_from_pos (TREE_PURPOSE (TREE_VALUE (gnu_entry)),
7148 TREE_VALUE (TREE_VALUE
7149 (TREE_VALUE (gnu_entry)))),
7152 Set_Esize (gnat_field,
7153 annotate_value (DECL_SIZE (TREE_PURPOSE (gnu_entry))));
7155 else if (Is_Tagged_Type (gnat_entity)
7156 && Is_Derived_Type (gnat_entity))
7158 /* If there is no gnu_entry, this is an inherited component whose
7159 position is the same as in the parent type. */
7160 Set_Component_Bit_Offset
7162 Component_Bit_Offset (Original_Record_Component (gnat_field)));
7163 Set_Esize (gnat_field,
7164 Esize (Original_Record_Component (gnat_field)));
7169 /* Scan all fields in GNU_TYPE and build entries where TREE_PURPOSE is the
7170 FIELD_DECL and TREE_VALUE a TREE_LIST with TREE_PURPOSE being the byte
7171 position and TREE_VALUE being a TREE_LIST with TREE_PURPOSE the value to be
7172 placed into DECL_OFFSET_ALIGN and TREE_VALUE the bit position. GNU_POS is
7173 to be added to the position, GNU_BITPOS to the bit position, OFFSET_ALIGN is
7174 the present value of DECL_OFFSET_ALIGN and GNU_LIST is a list of the entries
7178 compute_field_positions (tree gnu_type, tree gnu_list, tree gnu_pos,
7179 tree gnu_bitpos, unsigned int offset_align)
7182 tree gnu_result = gnu_list;
7184 for (gnu_field = TYPE_FIELDS (gnu_type); gnu_field;
7185 gnu_field = TREE_CHAIN (gnu_field))
7187 tree gnu_our_bitpos = size_binop (PLUS_EXPR, gnu_bitpos,
7188 DECL_FIELD_BIT_OFFSET (gnu_field));
7189 tree gnu_our_offset = size_binop (PLUS_EXPR, gnu_pos,
7190 DECL_FIELD_OFFSET (gnu_field));
7191 unsigned int our_offset_align
7192 = MIN (offset_align, DECL_OFFSET_ALIGN (gnu_field));
7195 = tree_cons (gnu_field,
7196 tree_cons (gnu_our_offset,
7197 tree_cons (size_int (our_offset_align),
7198 gnu_our_bitpos, NULL_TREE),
7202 if (DECL_INTERNAL_P (gnu_field))
7204 = compute_field_positions (TREE_TYPE (gnu_field), gnu_result,
7205 gnu_our_offset, gnu_our_bitpos,
7212 /* UINT_SIZE is a Uint giving the specified size for an object of GNU_TYPE
7213 corresponding to GNAT_OBJECT. If size is valid, return a tree corresponding
7214 to its value. Otherwise return 0. KIND is VAR_DECL is we are specifying
7215 the size for an object, TYPE_DECL for the size of a type, and FIELD_DECL
7216 for the size of a field. COMPONENT_P is true if we are being called
7217 to process the Component_Size of GNAT_OBJECT. This is used for error
7218 message handling and to indicate to use the object size of GNU_TYPE.
7219 ZERO_OK is true if a size of zero is permitted; if ZERO_OK is false,
7220 it means that a size of zero should be treated as an unspecified size. */
7223 validate_size (Uint uint_size, tree gnu_type, Entity_Id gnat_object,
7224 enum tree_code kind, bool component_p, bool zero_ok)
7226 Node_Id gnat_error_node;
7227 tree type_size, size;
7229 if (kind == VAR_DECL
7230 /* If a type needs strict alignment, a component of this type in
7231 a packed record cannot be packed and thus uses the type size. */
7232 || (kind == TYPE_DECL && Strict_Alignment (gnat_object)))
7233 type_size = TYPE_SIZE (gnu_type);
7235 type_size = rm_size (gnu_type);
7237 /* Find the node to use for errors. */
7238 if ((Ekind (gnat_object) == E_Component
7239 || Ekind (gnat_object) == E_Discriminant)
7240 && Present (Component_Clause (gnat_object)))
7241 gnat_error_node = Last_Bit (Component_Clause (gnat_object));
7242 else if (Present (Size_Clause (gnat_object)))
7243 gnat_error_node = Expression (Size_Clause (gnat_object));
7245 gnat_error_node = gnat_object;
7247 /* Return 0 if no size was specified, either because Esize was not Present
7248 or the specified size was zero. */
7249 if (No (uint_size) || uint_size == No_Uint)
7252 /* Get the size as a tree. Issue an error if a size was specified but
7253 cannot be represented in sizetype. */
7254 size = UI_To_gnu (uint_size, bitsizetype);
7255 if (TREE_OVERFLOW (size))
7257 post_error_ne (component_p ? "component size of & is too large"
7258 : "size of & is too large",
7259 gnat_error_node, gnat_object);
7263 /* Ignore a negative size since that corresponds to our back-annotation.
7264 Also ignore a zero size if it is not permitted. */
7265 if (tree_int_cst_sgn (size) < 0 || (integer_zerop (size) && !zero_ok))
7268 /* The size of objects is always a multiple of a byte. */
7269 if (kind == VAR_DECL
7270 && !integer_zerop (size_binop (TRUNC_MOD_EXPR, size, bitsize_unit_node)))
7273 post_error_ne ("component size for& is not a multiple of Storage_Unit",
7274 gnat_error_node, gnat_object);
7276 post_error_ne ("size for& is not a multiple of Storage_Unit",
7277 gnat_error_node, gnat_object);
7281 /* If this is an integral type or a packed array type, the front-end has
7282 verified the size, so we need not do it here (which would entail
7283 checking against the bounds). However, if this is an aliased object,
7284 it may not be smaller than the type of the object. */
7285 if ((INTEGRAL_TYPE_P (gnu_type) || TYPE_IS_PACKED_ARRAY_TYPE_P (gnu_type))
7286 && !(kind == VAR_DECL && Is_Aliased (gnat_object)))
7289 /* If the object is a record that contains a template, add the size of
7290 the template to the specified size. */
7291 if (TREE_CODE (gnu_type) == RECORD_TYPE
7292 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
7293 size = size_binop (PLUS_EXPR, DECL_SIZE (TYPE_FIELDS (gnu_type)), size);
7295 /* Modify the size of the type to be that of the maximum size if it has a
7297 if (type_size && CONTAINS_PLACEHOLDER_P (type_size))
7298 type_size = max_size (type_size, true);
7300 /* If this is an access type or a fat pointer, the minimum size is that given
7301 by the smallest integral mode that's valid for pointers. */
7302 if ((TREE_CODE (gnu_type) == POINTER_TYPE) || TYPE_FAT_POINTER_P (gnu_type))
7304 enum machine_mode p_mode;
7306 for (p_mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
7307 !targetm.valid_pointer_mode (p_mode);
7308 p_mode = GET_MODE_WIDER_MODE (p_mode))
7311 type_size = bitsize_int (GET_MODE_BITSIZE (p_mode));
7314 /* If the size of the object is a constant, the new size must not be
7316 if (TREE_CODE (type_size) != INTEGER_CST
7317 || TREE_OVERFLOW (type_size)
7318 || tree_int_cst_lt (size, type_size))
7322 ("component size for& too small{, minimum allowed is ^}",
7323 gnat_error_node, gnat_object, type_size);
7325 post_error_ne_tree ("size for& too small{, minimum allowed is ^}",
7326 gnat_error_node, gnat_object, type_size);
7328 if (kind == VAR_DECL && !component_p
7329 && TREE_CODE (rm_size (gnu_type)) == INTEGER_CST
7330 && !tree_int_cst_lt (size, rm_size (gnu_type)))
7331 post_error_ne_tree_2
7332 ("\\size of ^ is not a multiple of alignment (^ bits)",
7333 gnat_error_node, gnat_object, rm_size (gnu_type),
7334 TYPE_ALIGN (gnu_type));
7336 else if (INTEGRAL_TYPE_P (gnu_type))
7337 post_error_ne ("\\size would be legal if & were not aliased!",
7338 gnat_error_node, gnat_object);
7346 /* Similarly, but both validate and process a value of RM size. This
7347 routine is only called for types. */
7350 set_rm_size (Uint uint_size, tree gnu_type, Entity_Id gnat_entity)
7352 /* Only issue an error if a Value_Size clause was explicitly given.
7353 Otherwise, we'd be duplicating an error on the Size clause. */
7354 Node_Id gnat_attr_node
7355 = Get_Attribute_Definition_Clause (gnat_entity, Attr_Value_Size);
7356 tree old_size = rm_size (gnu_type), size;
7358 /* Do nothing if no size was specified, either because RM size was not
7359 Present or if the specified size was zero. */
7360 if (No (uint_size) || uint_size == No_Uint)
7363 /* Get the size as a tree. Issue an error if a size was specified but
7364 cannot be represented in sizetype. */
7365 size = UI_To_gnu (uint_size, bitsizetype);
7366 if (TREE_OVERFLOW (size))
7368 if (Present (gnat_attr_node))
7369 post_error_ne ("Value_Size of & is too large", gnat_attr_node,
7374 /* Ignore a negative size since that corresponds to our back-annotation.
7375 Also ignore a zero size unless a Value_Size clause exists, or a size
7376 clause exists, or this is an integer type, in which case the front-end
7377 will have always set it. */
7378 if (tree_int_cst_sgn (size) < 0
7379 || (integer_zerop (size)
7380 && No (gnat_attr_node)
7381 && !Has_Size_Clause (gnat_entity)
7382 && !Is_Discrete_Or_Fixed_Point_Type (gnat_entity)))
7385 /* If the old size is self-referential, get the maximum size. */
7386 if (CONTAINS_PLACEHOLDER_P (old_size))
7387 old_size = max_size (old_size, true);
7389 /* If the size of the object is a constant, the new size must not be
7390 smaller (the front-end checks this for scalar types). */
7391 if (TREE_CODE (old_size) != INTEGER_CST
7392 || TREE_OVERFLOW (old_size)
7393 || (AGGREGATE_TYPE_P (gnu_type) && tree_int_cst_lt (size, old_size)))
7395 if (Present (gnat_attr_node))
7397 ("Value_Size for& too small{, minimum allowed is ^}",
7398 gnat_attr_node, gnat_entity, old_size);
7402 /* Otherwise, set the RM size proper for integral types... */
7403 if ((TREE_CODE (gnu_type) == INTEGER_TYPE
7404 && Is_Discrete_Or_Fixed_Point_Type (gnat_entity))
7405 || (TREE_CODE (gnu_type) == ENUMERAL_TYPE
7406 || TREE_CODE (gnu_type) == BOOLEAN_TYPE))
7407 SET_TYPE_RM_SIZE (gnu_type, size);
7409 /* ...or the Ada size for record and union types. */
7410 else if ((TREE_CODE (gnu_type) == RECORD_TYPE
7411 || TREE_CODE (gnu_type) == UNION_TYPE
7412 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
7413 && !TYPE_IS_FAT_POINTER_P (gnu_type))
7414 SET_TYPE_ADA_SIZE (gnu_type, size);
7417 /* Given a type TYPE, return a new type whose size is appropriate for SIZE.
7418 If TYPE is the best type, return it. Otherwise, make a new type. We
7419 only support new integral and pointer types. FOR_BIASED is true if
7420 we are making a biased type. */
7423 make_type_from_size (tree type, tree size_tree, bool for_biased)
7425 unsigned HOST_WIDE_INT size;
7429 /* If size indicates an error, just return TYPE to avoid propagating
7430 the error. Likewise if it's too large to represent. */
7431 if (!size_tree || !host_integerp (size_tree, 1))
7434 size = tree_low_cst (size_tree, 1);
7436 switch (TREE_CODE (type))
7441 biased_p = (TREE_CODE (type) == INTEGER_TYPE
7442 && TYPE_BIASED_REPRESENTATION_P (type));
7444 /* Only do something if the type is not a packed array type and
7445 doesn't already have the proper size. */
7446 if (TYPE_PACKED_ARRAY_TYPE_P (type)
7447 || (TYPE_PRECISION (type) == size && biased_p == for_biased))
7450 biased_p |= for_biased;
7451 if (size > LONG_LONG_TYPE_SIZE)
7452 size = LONG_LONG_TYPE_SIZE;
7454 if (TYPE_UNSIGNED (type) || biased_p)
7455 new_type = make_unsigned_type (size);
7457 new_type = make_signed_type (size);
7458 TREE_TYPE (new_type) = TREE_TYPE (type) ? TREE_TYPE (type) : type;
7459 SET_TYPE_RM_MIN_VALUE (new_type,
7460 convert (TREE_TYPE (new_type),
7461 TYPE_MIN_VALUE (type)));
7462 SET_TYPE_RM_MAX_VALUE (new_type,
7463 convert (TREE_TYPE (new_type),
7464 TYPE_MAX_VALUE (type)));
7465 /* Propagate the name to avoid creating a fake subrange type. */
7466 if (TYPE_NAME (type))
7468 if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL)
7469 TYPE_NAME (new_type) = DECL_NAME (TYPE_NAME (type));
7471 TYPE_NAME (new_type) = TYPE_NAME (type);
7473 TYPE_BIASED_REPRESENTATION_P (new_type) = biased_p;
7474 SET_TYPE_RM_SIZE (new_type, bitsize_int (size));
7478 /* Do something if this is a fat pointer, in which case we
7479 may need to return the thin pointer. */
7480 if (TYPE_IS_FAT_POINTER_P (type) && size < POINTER_SIZE * 2)
7482 enum machine_mode p_mode = mode_for_size (size, MODE_INT, 0);
7483 if (!targetm.valid_pointer_mode (p_mode))
7486 build_pointer_type_for_mode
7487 (TYPE_OBJECT_RECORD_TYPE (TYPE_UNCONSTRAINED_ARRAY (type)),
7493 /* Only do something if this is a thin pointer, in which case we
7494 may need to return the fat pointer. */
7495 if (TYPE_THIN_POINTER_P (type) && size >= POINTER_SIZE * 2)
7497 build_pointer_type (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (type)));
7507 /* ALIGNMENT is a Uint giving the alignment specified for GNAT_ENTITY,
7508 a type or object whose present alignment is ALIGN. If this alignment is
7509 valid, return it. Otherwise, give an error and return ALIGN. */
7512 validate_alignment (Uint alignment, Entity_Id gnat_entity, unsigned int align)
7514 unsigned int max_allowed_alignment = get_target_maximum_allowed_alignment ();
7515 unsigned int new_align;
7516 Node_Id gnat_error_node;
7518 /* Don't worry about checking alignment if alignment was not specified
7519 by the source program and we already posted an error for this entity. */
7520 if (Error_Posted (gnat_entity) && !Has_Alignment_Clause (gnat_entity))
7523 /* Post the error on the alignment clause if any. */
7524 if (Present (Alignment_Clause (gnat_entity)))
7525 gnat_error_node = Expression (Alignment_Clause (gnat_entity));
7527 gnat_error_node = gnat_entity;
7529 /* Within GCC, an alignment is an integer, so we must make sure a value is
7530 specified that fits in that range. Also, there is an upper bound to
7531 alignments we can support/allow. */
7532 if (!UI_Is_In_Int_Range (alignment)
7533 || ((new_align = UI_To_Int (alignment)) > max_allowed_alignment))
7534 post_error_ne_num ("largest supported alignment for& is ^",
7535 gnat_error_node, gnat_entity, max_allowed_alignment);
7536 else if (!(Present (Alignment_Clause (gnat_entity))
7537 && From_At_Mod (Alignment_Clause (gnat_entity)))
7538 && new_align * BITS_PER_UNIT < align)
7540 unsigned int double_align;
7541 bool is_capped_double, align_clause;
7543 /* If the default alignment of "double" or larger scalar types is
7544 specifically capped and the new alignment is above the cap, do
7545 not post an error and change the alignment only if there is an
7546 alignment clause; this makes it possible to have the associated
7547 GCC type overaligned by default for performance reasons. */
7548 if ((double_align = double_float_alignment) > 0)
7551 = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity);
7553 = is_double_float_or_array (gnat_type, &align_clause);
7555 else if ((double_align = double_scalar_alignment) > 0)
7558 = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity);
7560 = is_double_scalar_or_array (gnat_type, &align_clause);
7563 is_capped_double = align_clause = false;
7565 if (is_capped_double && new_align >= double_align)
7568 align = new_align * BITS_PER_UNIT;
7572 if (is_capped_double)
7573 align = double_align * BITS_PER_UNIT;
7575 post_error_ne_num ("alignment for& must be at least ^",
7576 gnat_error_node, gnat_entity,
7577 align / BITS_PER_UNIT);
7582 new_align = (new_align > 0 ? new_align * BITS_PER_UNIT : 1);
7583 if (new_align > align)
7590 /* Return the smallest alignment not less than SIZE. */
7593 ceil_alignment (unsigned HOST_WIDE_INT size)
7595 return (unsigned int) 1 << (floor_log2 (size - 1) + 1);
7598 /* Verify that OBJECT, a type or decl, is something we can implement
7599 atomically. If not, give an error for GNAT_ENTITY. COMP_P is true
7600 if we require atomic components. */
7603 check_ok_for_atomic (tree object, Entity_Id gnat_entity, bool comp_p)
7605 Node_Id gnat_error_point = gnat_entity;
7607 enum machine_mode mode;
7611 /* There are three case of what OBJECT can be. It can be a type, in which
7612 case we take the size, alignment and mode from the type. It can be a
7613 declaration that was indirect, in which case the relevant values are
7614 that of the type being pointed to, or it can be a normal declaration,
7615 in which case the values are of the decl. The code below assumes that
7616 OBJECT is either a type or a decl. */
7617 if (TYPE_P (object))
7619 mode = TYPE_MODE (object);
7620 align = TYPE_ALIGN (object);
7621 size = TYPE_SIZE (object);
7623 else if (DECL_BY_REF_P (object))
7625 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (object)));
7626 align = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (object)));
7627 size = TYPE_SIZE (TREE_TYPE (TREE_TYPE (object)));
7631 mode = DECL_MODE (object);
7632 align = DECL_ALIGN (object);
7633 size = DECL_SIZE (object);
7636 /* Consider all floating-point types atomic and any types that that are
7637 represented by integers no wider than a machine word. */
7638 if (GET_MODE_CLASS (mode) == MODE_FLOAT
7639 || ((GET_MODE_CLASS (mode) == MODE_INT
7640 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
7641 && GET_MODE_BITSIZE (mode) <= BITS_PER_WORD))
7644 /* For the moment, also allow anything that has an alignment equal
7645 to its size and which is smaller than a word. */
7646 if (size && TREE_CODE (size) == INTEGER_CST
7647 && compare_tree_int (size, align) == 0
7648 && align <= BITS_PER_WORD)
7651 for (gnat_node = First_Rep_Item (gnat_entity); Present (gnat_node);
7652 gnat_node = Next_Rep_Item (gnat_node))
7654 if (!comp_p && Nkind (gnat_node) == N_Pragma
7655 && (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node)))
7657 gnat_error_point = First (Pragma_Argument_Associations (gnat_node));
7658 else if (comp_p && Nkind (gnat_node) == N_Pragma
7659 && (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node)))
7660 == Pragma_Atomic_Components))
7661 gnat_error_point = First (Pragma_Argument_Associations (gnat_node));
7665 post_error_ne ("atomic access to component of & cannot be guaranteed",
7666 gnat_error_point, gnat_entity);
7668 post_error_ne ("atomic access to & cannot be guaranteed",
7669 gnat_error_point, gnat_entity);
7672 /* Check if FTYPE1 and FTYPE2, two potentially different function type nodes,
7673 have compatible signatures so that a call using one type may be safely
7674 issued if the actual target function type is the other. Return 1 if it is
7675 the case, 0 otherwise, and post errors on the incompatibilities.
7677 This is used when an Ada subprogram is mapped onto a GCC builtin, to ensure
7678 that calls to the subprogram will have arguments suitable for the later
7679 underlying builtin expansion. */
7682 compatible_signatures_p (tree ftype1, tree ftype2)
7684 /* As of now, we only perform very trivial tests and consider it's the
7685 programmer's responsibility to ensure the type correctness in the Ada
7686 declaration, as in the regular Import cases.
7688 Mismatches typically result in either error messages from the builtin
7689 expander, internal compiler errors, or in a real call sequence. This
7690 should be refined to issue diagnostics helping error detection and
7693 /* Almost fake test, ensuring a use of each argument. */
7694 if (ftype1 == ftype2)
7700 /* Given a type T, a FIELD_DECL F, and a replacement value R, return a
7701 type with all size expressions that contain F in a PLACEHOLDER_EXPR
7702 updated by replacing F with R.
7704 The function doesn't update the layout of the type, i.e. it assumes
7705 that the substitution is purely formal. That's why the replacement
7706 value R must itself contain a PLACEHOLDER_EXPR. */
7709 substitute_in_type (tree t, tree f, tree r)
7713 gcc_assert (CONTAINS_PLACEHOLDER_P (r));
7715 switch (TREE_CODE (t))
7722 /* First the domain types of arrays. */
7723 if (CONTAINS_PLACEHOLDER_P (TYPE_GCC_MIN_VALUE (t))
7724 || CONTAINS_PLACEHOLDER_P (TYPE_GCC_MAX_VALUE (t)))
7726 tree low = SUBSTITUTE_IN_EXPR (TYPE_GCC_MIN_VALUE (t), f, r);
7727 tree high = SUBSTITUTE_IN_EXPR (TYPE_GCC_MAX_VALUE (t), f, r);
7729 if (low == TYPE_GCC_MIN_VALUE (t) && high == TYPE_GCC_MAX_VALUE (t))
7732 new = copy_type (t);
7733 TYPE_GCC_MIN_VALUE (new) = low;
7734 TYPE_GCC_MAX_VALUE (new) = high;
7736 if (TREE_CODE (t) == INTEGER_TYPE && TYPE_INDEX_TYPE (t))
7738 (new, substitute_in_type (TYPE_INDEX_TYPE (t), f, r));
7743 /* Then the subtypes. */
7744 if (CONTAINS_PLACEHOLDER_P (TYPE_RM_MIN_VALUE (t))
7745 || CONTAINS_PLACEHOLDER_P (TYPE_RM_MAX_VALUE (t)))
7747 tree low = SUBSTITUTE_IN_EXPR (TYPE_RM_MIN_VALUE (t), f, r);
7748 tree high = SUBSTITUTE_IN_EXPR (TYPE_RM_MAX_VALUE (t), f, r);
7750 if (low == TYPE_RM_MIN_VALUE (t) && high == TYPE_RM_MAX_VALUE (t))
7753 new = copy_type (t);
7754 SET_TYPE_RM_MIN_VALUE (new, low);
7755 SET_TYPE_RM_MAX_VALUE (new, high);
7763 new = substitute_in_type (TREE_TYPE (t), f, r);
7764 if (new == TREE_TYPE (t))
7767 return build_complex_type (new);
7773 /* These should never show up here. */
7778 tree component = substitute_in_type (TREE_TYPE (t), f, r);
7779 tree domain = substitute_in_type (TYPE_DOMAIN (t), f, r);
7781 if (component == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7784 new = build_array_type (component, domain);
7785 TYPE_ALIGN (new) = TYPE_ALIGN (t);
7786 TYPE_USER_ALIGN (new) = TYPE_USER_ALIGN (t);
7787 SET_TYPE_MODE (new, TYPE_MODE (t));
7788 TYPE_SIZE (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r);
7789 TYPE_SIZE_UNIT (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r);
7790 TYPE_NONALIASED_COMPONENT (new) = TYPE_NONALIASED_COMPONENT (t);
7791 TYPE_MULTI_ARRAY_P (new) = TYPE_MULTI_ARRAY_P (t);
7792 TYPE_CONVENTION_FORTRAN_P (new) = TYPE_CONVENTION_FORTRAN_P (t);
7798 case QUAL_UNION_TYPE:
7800 bool changed_field = false;
7803 /* Start out with no fields, make new fields, and chain them
7804 in. If we haven't actually changed the type of any field,
7805 discard everything we've done and return the old type. */
7806 new = copy_type (t);
7807 TYPE_FIELDS (new) = NULL_TREE;
7809 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
7811 tree new_field = copy_node (field), new_n;
7813 new_n = substitute_in_type (TREE_TYPE (field), f, r);
7814 if (new_n != TREE_TYPE (field))
7816 TREE_TYPE (new_field) = new_n;
7817 changed_field = true;
7820 new_n = SUBSTITUTE_IN_EXPR (DECL_FIELD_OFFSET (field), f, r);
7821 if (new_n != DECL_FIELD_OFFSET (field))
7823 DECL_FIELD_OFFSET (new_field) = new_n;
7824 changed_field = true;
7827 /* Do the substitution inside the qualifier, if any. */
7828 if (TREE_CODE (t) == QUAL_UNION_TYPE)
7830 new_n = SUBSTITUTE_IN_EXPR (DECL_QUALIFIER (field), f, r);
7831 if (new_n != DECL_QUALIFIER (field))
7833 DECL_QUALIFIER (new_field) = new_n;
7834 changed_field = true;
7838 DECL_CONTEXT (new_field) = new;
7839 SET_DECL_ORIGINAL_FIELD (new_field,
7840 (DECL_ORIGINAL_FIELD (field)
7841 ? DECL_ORIGINAL_FIELD (field) : field));
7843 TREE_CHAIN (new_field) = TYPE_FIELDS (new);
7844 TYPE_FIELDS (new) = new_field;
7850 TYPE_FIELDS (new) = nreverse (TYPE_FIELDS (new));
7851 TYPE_SIZE (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r);
7852 TYPE_SIZE_UNIT (new) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r);
7853 SET_TYPE_ADA_SIZE (new, SUBSTITUTE_IN_EXPR (TYPE_ADA_SIZE (t), f, r));
7862 /* Return the RM size of GNU_TYPE. This is the actual number of bits
7863 needed to represent the object. */
7866 rm_size (tree gnu_type)
7868 /* For integral types, we store the RM size explicitly. */
7869 if (INTEGRAL_TYPE_P (gnu_type) && TYPE_RM_SIZE (gnu_type))
7870 return TYPE_RM_SIZE (gnu_type);
7872 /* Return the RM size of the actual data plus the size of the template. */
7873 if (TREE_CODE (gnu_type) == RECORD_TYPE
7874 && TYPE_CONTAINS_TEMPLATE_P (gnu_type))
7876 size_binop (PLUS_EXPR,
7877 rm_size (TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_type)))),
7878 DECL_SIZE (TYPE_FIELDS (gnu_type)));
7880 /* For record types, we store the size explicitly. */
7881 if ((TREE_CODE (gnu_type) == RECORD_TYPE
7882 || TREE_CODE (gnu_type) == UNION_TYPE
7883 || TREE_CODE (gnu_type) == QUAL_UNION_TYPE)
7884 && !TYPE_IS_FAT_POINTER_P (gnu_type)
7885 && TYPE_ADA_SIZE (gnu_type))
7886 return TYPE_ADA_SIZE (gnu_type);
7888 /* For other types, this is just the size. */
7889 return TYPE_SIZE (gnu_type);
7892 /* Return the name to be used for GNAT_ENTITY. If a type, create a
7893 fully-qualified name, possibly with type information encoding.
7894 Otherwise, return the name. */
7897 get_entity_name (Entity_Id gnat_entity)
7899 Get_Encoded_Name (gnat_entity);
7900 return get_identifier_with_length (Name_Buffer, Name_Len);
7903 /* Return an identifier representing the external name to be used for
7904 GNAT_ENTITY. If SUFFIX is specified, the name is followed by "___"
7905 and the specified suffix. */
7908 create_concat_name (Entity_Id gnat_entity, const char *suffix)
7910 Entity_Kind kind = Ekind (gnat_entity);
7914 String_Template temp = {1, strlen (suffix)};
7915 Fat_Pointer fp = {suffix, &temp};
7916 Get_External_Name_With_Suffix (gnat_entity, fp);
7919 Get_External_Name (gnat_entity, 0);
7921 /* A variable using the Stdcall convention lives in a DLL. We adjust
7922 its name to use the jump table, the _imp__NAME contains the address
7923 for the NAME variable. */
7924 if ((kind == E_Variable || kind == E_Constant)
7925 && Has_Stdcall_Convention (gnat_entity))
7927 const int len = 6 + Name_Len;
7928 char *new_name = (char *) alloca (len + 1);
7929 strcpy (new_name, "_imp__");
7930 strcat (new_name, Name_Buffer);
7931 return get_identifier_with_length (new_name, len);
7934 return get_identifier_with_length (Name_Buffer, Name_Len);
7937 /* Given GNU_NAME, an IDENTIFIER_NODE containing a name and SUFFIX, a
7938 string, return a new IDENTIFIER_NODE that is the concatenation of
7939 the name followed by "___" and the specified suffix. */
7942 concat_name (tree gnu_name, const char *suffix)
7944 const int len = IDENTIFIER_LENGTH (gnu_name) + 3 + strlen (suffix);
7945 char *new_name = (char *) alloca (len + 1);
7946 strcpy (new_name, IDENTIFIER_POINTER (gnu_name));
7947 strcat (new_name, "___");
7948 strcat (new_name, suffix);
7949 return get_identifier_with_length (new_name, len);
7952 #include "gt-ada-decl.h"