1 /****************************************************************************
2  *                                                                          *
3  *                         GNAT COMPILER COMPONENTS                         *
4  *                                                                          *
5  *                                 G I G I                                  *
6  *                                                                          *
7  *                              C Header File                               *
8  *                                                                          *
9  *          Copyright (C) 1992-2018, Free Software Foundation, Inc.         *
10  *                                                                          *
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  distributed  with GNAT;  see file  COPYING3.  If not see *
19  * <http://www.gnu.org/licenses/>.                                          *
20  *                                                                          *
21  * GNAT was originally developed  by the GNAT team at  New York University. *
22  * Extensive contributions were provided by Ada Core Technologies Inc.      *
23  *                                                                          *
24  ****************************************************************************/
25 
26 /* Declare all functions and types used by gigi.  */
27 
28 /* Given GNAT_ENTITY, a GNAT defining identifier node, which denotes some Ada
29    entity, this routine returns the equivalent GCC tree for that entity
30    (an ..._DECL node) and associates the ..._DECL node with the input GNAT
31    defining identifier.
32 
33    If GNAT_ENTITY is a variable or a constant declaration, GNU_EXPR gives its
34    initial value (in GCC tree form). This is optional for variables.
35    For renamed entities, GNU_EXPR gives the object being renamed.
36 
37    DEFINITION is true if this call is intended for a definition.  This is used
38    for separate compilation where it is necessary to know whether an external
39    declaration or a definition must be created if the GCC equivalent was not
40    created previously.  */
41 extern tree gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr,
42                                 bool definition);
43 
44 /* Similar, but if the returned value is a COMPONENT_REF, return the
45    FIELD_DECL.  */
46 extern tree gnat_to_gnu_field_decl (Entity_Id gnat_entity);
47 
48 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type.  Return
49    the GCC type corresponding to that entity.  */
50 extern tree gnat_to_gnu_type (Entity_Id gnat_entity);
51 
52 /* Update the GCC tree previously built for the profiles involving GNU_TYPE,
53    a dummy type which appears in profiles.  */
54 extern void update_profiles_with (tree gnu_type);
55 
56 /* Start a new statement group chained to the previous group.  */
57 extern void start_stmt_group (void);
58 
59 /* Add GNU_STMT to the current statement group.  If it is an expression with
60    no effects, it is ignored.  */
61 extern void add_stmt (tree gnu_stmt);
62 
63 /* Similar, but the statement is always added, regardless of side-effects.  */
64 extern void add_stmt_force (tree gnu_stmt);
65 
66 /* Like add_stmt, but set the location of GNU_STMT to that of GNAT_NODE.  */
67 extern void add_stmt_with_node (tree gnu_stmt, Node_Id gnat_node);
68 
69 /* Similar, but the statement is always added, regardless of side-effects.  */
70 extern void add_stmt_with_node_force (tree gnu_stmt, Node_Id gnat_node);
71 
72 /* Return code corresponding to the current code group.  It is normally
73    a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
74    BLOCK or cleanups were set.  */
75 extern tree end_stmt_group (void);
76 
77 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK.  */
78 extern void set_block_for_group (tree);
79 
80 /* Add a declaration statement for GNU_DECL to the current statement group.
81    Get the SLOC to be put onto the statement from GNAT_NODE.  */
82 extern void add_decl_expr (tree gnu_decl, Node_Id gnat_node);
83 
84 /* Mark nodes rooted at T with TREE_VISITED and types as having their
85    sized gimplified.  We use this to indicate all variable sizes and
86    positions in global types may not be shared by any subprogram.  */
87 extern void mark_visited (tree t);
88 
89 /* This macro calls the above function but short-circuits the common
90    case of a constant to save time and also checks for NULL.  */
91 #define MARK_VISITED(EXP)		\
92 do {					\
93   if((EXP) && !CONSTANT_CLASS_P (EXP))	\
94     mark_visited (EXP);			\
95 } while (0)
96 
97 /* Finalize the processing of From_Limited_With incomplete types.  */
98 extern void finalize_from_limited_with (void);
99 
100 /* Return the equivalent type to be used for GNAT_ENTITY, if it's a kind
101    of type (such E_Task_Type) that has a different type which Gigi uses
102    for its representation.  If the type does not have a special type for
103    its representation, return GNAT_ENTITY.  */
104 extern Entity_Id Gigi_Equivalent_Type (Entity_Id gnat_entity);
105 
106 /* Given GNAT_ENTITY, elaborate all expressions that are required to
107    be elaborated at the point of its definition, but do nothing else.  */
108 extern void elaborate_entity (Entity_Id gnat_entity);
109 
110 /* Get the unpadded version of a GNAT type.  */
111 extern tree get_unpadded_type (Entity_Id gnat_entity);
112 
113 /* Create a record type that contains a SIZE bytes long field of TYPE with a
114     starting bit position so that it is aligned to ALIGN bits, and leaving at
115     least ROOM bytes free before the field.  BASE_ALIGN is the alignment the
116     record is guaranteed to get.  GNAT_NODE is used for the position of the
117     associated TYPE_DECL.  */
118 extern tree make_aligning_type (tree type, unsigned int align, tree size,
119 				unsigned int base_align, int room, Node_Id);
120 
121 /* TYPE is a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE that is being used
122    as the field type of a packed record if IN_RECORD is true, or as the
123    component type of a packed array if IN_RECORD is false.  See if we can
124    rewrite it either as a type that has a non-BLKmode, which we can pack
125    tighter in the packed record case, or as a smaller type with at most
126    MAX_ALIGN alignment if the value is non-zero.  If so, return the new
127    type; if not, return the original type.  */
128 extern tree make_packable_type (tree type, bool in_record,
129 				unsigned int max_align = 0);
130 
131 /* Given a type TYPE, return a new type whose size is appropriate for SIZE.
132    If TYPE is the best type, return it.  Otherwise, make a new type.  We
133    only support new integral and pointer types.  FOR_BIASED is true if
134    we are making a biased type.  */
135 extern tree make_type_from_size (tree type, tree size_tree, bool for_biased);
136 
137 /* Ensure that TYPE has SIZE and ALIGN.  Make and return a new padded type
138    if needed.  We have already verified that SIZE and ALIGN are large enough.
139    GNAT_ENTITY is used to name the resulting record and to issue a warning.
140    IS_COMPONENT_TYPE is true if this is being done for the component type of
141    an array.  IS_USER_TYPE is true if the original type needs to be completed.
142    DEFINITION is true if this type is being defined.  SET_RM_SIZE is true if
143    the RM size of the resulting type is to be set to SIZE too; in this case,
144    the padded type is canonicalized before being returned.  */
145 extern tree maybe_pad_type (tree type, tree size, unsigned int align,
146 			    Entity_Id gnat_entity, bool is_component_type,
147 			    bool is_user_type, bool definition,
148 			    bool set_rm_size);
149 
150 /* Return true if padded TYPE was built with an RM size.  */
151 extern bool pad_type_has_rm_size (tree type);
152 
153 /* Return a copy of the padded TYPE but with reverse storage order.  */
154 extern tree set_reverse_storage_order_on_pad_type (tree type);
155 
156 enum alias_set_op
157 {
158   ALIAS_SET_COPY,
159   ALIAS_SET_SUBSET,
160   ALIAS_SET_SUPERSET
161 };
162 
163 /* Relate the alias sets of GNU_NEW_TYPE and GNU_OLD_TYPE according to OP.
164    If this is a multi-dimensional array type, do this recursively.
165 
166    OP may be
167    - ALIAS_SET_COPY:     the new set is made a copy of the old one.
168    - ALIAS_SET_SUPERSET: the new set is made a superset of the old one.
169    - ALIAS_SET_SUBSET:   the new set is made a subset of the old one.  */
170 extern void relate_alias_sets (tree gnu_new_type, tree gnu_old_type,
171 			       enum alias_set_op op);
172 
173 /* Given GNAT_ENTITY, an object (constant, variable, parameter, exception)
174    and GNU_TYPE, its corresponding GCC type, set Esize and Alignment to the
175    size and alignment used by Gigi.  Prefer SIZE over TYPE_SIZE if non-null.
176    BY_REF is true if the object is used by reference.  */
177 extern void annotate_object (Entity_Id gnat_entity, tree gnu_type, tree size,
178 			     bool by_ref);
179 
180 /* Return the variant part of RECORD_TYPE, if any.  Otherwise return NULL.  */
181 extern tree get_variant_part (tree record_type);
182 
183 /* Given a type T, a FIELD_DECL F, and a replacement value R, return a new
184    type with all size expressions that contain F updated by replacing F
185    with R.  If F is NULL_TREE, always make a new RECORD_TYPE, even if
186    nothing has changed.  */
187 extern tree substitute_in_type (tree t, tree f, tree r);
188 
189 /* Return the RM size of GNU_TYPE.  This is the actual number of bits
190    needed to represent the object.  */
191 extern tree rm_size (tree gnu_type);
192 
193 /* Return the name to be used for GNAT_ENTITY.  If a type, create a
194    fully-qualified name, possibly with type information encoding.
195    Otherwise, return the name.  */
196 extern tree get_entity_name (Entity_Id gnat_entity);
197 
198 /* Return an identifier representing the external name to be used for
199    GNAT_ENTITY.  If SUFFIX is specified, the name is followed by "___"
200    and the specified suffix.  */
201 extern tree create_concat_name (Entity_Id gnat_entity, const char *suffix);
202 
203 /* Given GNU_NAME, an IDENTIFIER_NODE containing a name and SUFFIX, a
204    string, return a new IDENTIFIER_NODE that is the concatenation of
205    the name followed by "___" and the specified suffix.  */
206 extern tree concat_name (tree gnu_name, const char *suffix);
207 
208 /* Initialize data structures of the decl.c module.  */
209 extern void init_gnat_decl (void);
210 
211 /* Destroy data structures of the decl.c module.  */
212 extern void destroy_gnat_decl (void);
213 
214 /* Highest number in the front-end node table.  */
215 extern int max_gnat_nodes;
216 
217 /* True when gigi is being called on an analyzed but unexpanded
218    tree, and the only purpose of the call is to properly annotate
219    types with representation information.  */
220 extern bool type_annotate_only;
221 
222 /* This structure must be kept synchronized with Call_Back_End.  */
223 struct File_Info_Type
224 {
225   File_Name_Type File_Name;
226   Instance_Id    Instance;
227   Nat            Num_Source_Lines;
228 };
229 
230 #ifdef __cplusplus
231 extern "C" {
232 #endif
233 
234 /* This is the main program of the back-end.  It sets up all the table
235    structures and then generates code.  */
236 extern void gigi (Node_Id gnat_root,
237 	          int max_gnat_node,
238                   int number_name,
239 		  struct Node *nodes_ptr,
240 		  struct Flags *Flags_Ptr,
241 		  Node_Id *next_node_ptr,
242 		  Node_Id *prev_node_ptr,
243 		  struct Elist_Header *elists_ptr,
244                   struct Elmt_Item *elmts_ptr,
245                   struct String_Entry *strings_ptr,
246                   Char_Code *strings_chars_ptr,
247                   struct List_Header *list_headers_ptr,
248                   Nat number_file,
249                   struct File_Info_Type *file_info_ptr,
250                   Entity_Id standard_boolean,
251                   Entity_Id standard_integer,
252                   Entity_Id standard_character,
253                   Entity_Id standard_long_long_float,
254                   Entity_Id standard_exception_type,
255                   Int gigi_operating_mode);
256 
257 #ifdef __cplusplus
258 }
259 #endif
260 
261 /* GNAT_NODE is the root of some GNAT tree.  Return the root of the
262    GCC tree corresponding to that GNAT tree.  */
263 extern tree gnat_to_gnu (Node_Id gnat_node);
264 
265 /* Similar to gnat_to_gnu, but discard any object that might be created in
266    the course of the translation of GNAT_NODE, which must be an "external"
267    expression in the sense that it will be elaborated elsewhere.  */
268 extern tree gnat_to_gnu_external (Node_Id gnat_node);
269 
270 /* GNU_STMT is a statement.  We generate code for that statement.  */
271 extern void gnat_expand_stmt (tree gnu_stmt);
272 
273 /* Generate GIMPLE in place for the expression at *EXPR_P.  */
274 extern int gnat_gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *);
275 
276 /* Do the processing for the declaration of a GNAT_ENTITY, a type.  If
277    a separate Freeze node exists, delay the bulk of the processing.  Otherwise
278    make a GCC type for GNAT_ENTITY and set up the correspondence.  */
279 extern void process_type (Entity_Id gnat_entity);
280 
281 /* Convert SLOC into LOCUS.  Return true if SLOC corresponds to a source code
282    location and false if it doesn't.  If CLEAR_COLUMN is true, set the column
283    information to 0.  */
284 extern bool Sloc_to_locus (Source_Ptr Sloc, location_t *locus,
285 			   bool clear_column = false, const_tree decl = 0);
286 
287 /* Post an error message.  MSG is the error message, properly annotated.
288    NODE is the node at which to post the error and the node to use for the
289    '&' substitution.  */
290 extern void post_error (const char *msg, Node_Id node);
291 
292 /* Similar to post_error, but NODE is the node at which to post the error and
293    ENT is the node to use for the '&' substitution.  */
294 extern void post_error_ne (const char *msg, Node_Id node, Entity_Id ent);
295 
296 /* Similar to post_error_ne, but NUM is the number to use for the '^'.  */
297 extern void post_error_ne_num (const char *msg, Node_Id node, Entity_Id ent,
298                                int num);
299 
300 /* Similar to post_error_ne, but T is a GCC tree representing the number to
301    write.  If T represents a constant, the text inside curly brackets in
302    MSG will be output (presumably including a '^').  Otherwise it will not
303    be output and the text inside square brackets will be output instead.  */
304 extern void post_error_ne_tree (const char *msg, Node_Id node, Entity_Id ent,
305                                 tree t);
306 
307 /* Similar to post_error_ne_tree, but NUM is a second integer to write.  */
308 extern void post_error_ne_tree_2 (const char *msg, Node_Id node, Entity_Id ent,
309                                   tree t, int num);
310 
311 /* Return a label to branch to for the exception type in KIND or Empty
312    if none.  */
313 extern Entity_Id get_exception_label (char kind);
314 
315 /* If nonzero, pretend we are allocating at global level.  */
316 extern int force_global;
317 
318 /* The default alignment of "double" floating-point types, i.e. floating
319    point types whose size is equal to 64 bits, or 0 if this alignment is
320    not specifically capped.  */
321 extern int double_float_alignment;
322 
323 /* The default alignment of "double" or larger scalar types, i.e. scalar
324    types whose size is greater or equal to 64 bits, or 0 if this alignment
325    is not specifically capped.  */
326 extern int double_scalar_alignment;
327 
328 /* True if floating-point arithmetics may use wider intermediate results.  */
329 extern bool fp_arith_may_widen;
330 
331 /* Data structures used to represent attributes.  */
332 
333 enum attrib_type
334 {
335   ATTR_MACHINE_ATTRIBUTE,
336   ATTR_LINK_ALIAS,
337   ATTR_LINK_SECTION,
338   ATTR_LINK_CONSTRUCTOR,
339   ATTR_LINK_DESTRUCTOR,
340   ATTR_THREAD_LOCAL_STORAGE,
341   ATTR_WEAK_EXTERNAL
342 };
343 
344 struct attrib
345 {
346   struct attrib *next;
347   enum attrib_type type;
348   tree name;
349   tree args;
350   Node_Id error_point;
351 };
352 
353 /* Table of machine-independent internal attributes.  */
354 extern const struct attribute_spec gnat_internal_attribute_table[];
355 
356 /* Define the entries in the standard data array.  */
357 enum standard_datatypes
358 {
359   /* The longest floating-point type.  */
360   ADT_longest_float_type,
361 
362   /* The type of an exception.  */
363   ADT_except_type,
364 
365   /* Function type declaration -- void T() */
366   ADT_void_ftype,
367 
368   /* Type declaration node  <==> typedef void *T() */
369   ADT_ptr_void_ftype,
370 
371   /* Type declaration node  <==> typedef virtual void *T() */
372   ADT_fdesc_type,
373 
374   /* Null pointer for above type.  */
375   ADT_null_fdesc,
376 
377   /* Value 1 in signed bitsizetype.  */
378   ADT_sbitsize_one_node,
379 
380   /* Value BITS_PER_UNIT in signed bitsizetype.  */
381   ADT_sbitsize_unit_node,
382 
383   /* Function declaration node for run-time allocation function.  */
384   ADT_malloc_decl,
385 
386   /* Function declaration node for run-time freeing function.  */
387   ADT_free_decl,
388 
389   /* Function declaration node for run-time reallocation function.  */
390   ADT_realloc_decl,
391 
392   /* Function decl node for 64-bit multiplication with overflow checking.  */
393   ADT_mulv64_decl,
394 
395   /* Identifier for the name of the _Parent field in tagged record types.  */
396   ADT_parent_name_id,
397 
398   /* Identifier for the name of the Exception_Data type.  */
399   ADT_exception_data_name_id,
400 
401   /* Types and decls used by the SJLJ exception mechanism.  */
402   ADT_jmpbuf_type,
403   ADT_jmpbuf_ptr_type,
404   ADT_get_jmpbuf_decl,
405   ADT_set_jmpbuf_decl,
406   ADT_get_excptr_decl,
407   ADT_not_handled_by_others_decl,
408   ADT_setjmp_decl,
409   ADT_update_setjmp_buf_decl,
410   ADT_raise_nodefer_decl,
411 
412   /* Types and decls used by the ZCX exception mechanism.  */
413   ADT_reraise_zcx_decl,
414   ADT_set_exception_parameter_decl,
415   ADT_begin_handler_decl,
416   ADT_end_handler_decl,
417   ADT_unhandled_except_decl,
418   ADT_others_decl,
419   ADT_all_others_decl,
420   ADT_unhandled_others_decl,
421 
422   ADT_LAST
423 };
424 
425 /* Define kind of exception information associated with raise statements.  */
426 enum exception_info_kind
427 {
428   /* Simple exception information: file:line.  */
429   exception_simple,
430   /* Range exception information: file:line + index, first, last.  */
431   exception_range,
432   /* Column exception information: file:line:column.  */
433   exception_column
434 };
435 
436 /* Define the inline status of a subprogram.  */
437 enum inline_status_t
438 {
439   /* Inlining is suppressed for the subprogram.  */
440   is_suppressed,
441   /* No inlining is requested for the subprogram.  */
442   is_default,
443   /* Inlining is requested for the subprogram.  */
444   is_requested,
445   /* Inlining is strongly requested for the subprogram.  */
446   is_prescribed,
447   /* Inlining is required for the subprogram.  */
448   is_required
449 };
450 
451 extern GTY(()) tree gnat_std_decls[(int) ADT_LAST];
452 extern GTY(()) tree gnat_raise_decls[(int) LAST_REASON_CODE + 1];
453 extern GTY(()) tree gnat_raise_decls_ext[(int) LAST_REASON_CODE + 1];
454 
455 #define longest_float_type_node gnat_std_decls[(int) ADT_longest_float_type]
456 #define except_type_node gnat_std_decls[(int) ADT_except_type]
457 #define void_ftype gnat_std_decls[(int) ADT_void_ftype]
458 #define ptr_void_ftype gnat_std_decls[(int) ADT_ptr_void_ftype]
459 #define fdesc_type_node gnat_std_decls[(int) ADT_fdesc_type]
460 #define null_fdesc_node gnat_std_decls[(int) ADT_null_fdesc]
461 #define sbitsize_one_node gnat_std_decls[(int) ADT_sbitsize_one_node]
462 #define sbitsize_unit_node gnat_std_decls[(int) ADT_sbitsize_unit_node]
463 #define malloc_decl gnat_std_decls[(int) ADT_malloc_decl]
464 #define free_decl gnat_std_decls[(int) ADT_free_decl]
465 #define realloc_decl gnat_std_decls[(int) ADT_realloc_decl]
466 #define mulv64_decl gnat_std_decls[(int) ADT_mulv64_decl]
467 #define parent_name_id gnat_std_decls[(int) ADT_parent_name_id]
468 #define exception_data_name_id gnat_std_decls[(int) ADT_exception_data_name_id]
469 #define jmpbuf_type gnat_std_decls[(int) ADT_jmpbuf_type]
470 #define jmpbuf_ptr_type gnat_std_decls[(int) ADT_jmpbuf_ptr_type]
471 #define get_jmpbuf_decl gnat_std_decls[(int) ADT_get_jmpbuf_decl]
472 #define set_jmpbuf_decl gnat_std_decls[(int) ADT_set_jmpbuf_decl]
473 #define get_excptr_decl gnat_std_decls[(int) ADT_get_excptr_decl]
474 #define not_handled_by_others_decl \
475 	  gnat_std_decls[(int) ADT_not_handled_by_others_decl]
476 #define setjmp_decl gnat_std_decls[(int) ADT_setjmp_decl]
477 #define update_setjmp_buf_decl gnat_std_decls[(int) ADT_update_setjmp_buf_decl]
478 #define raise_nodefer_decl gnat_std_decls[(int) ADT_raise_nodefer_decl]
479 #define reraise_zcx_decl gnat_std_decls[(int) ADT_reraise_zcx_decl]
480 #define set_exception_parameter_decl \
481 	  gnat_std_decls[(int) ADT_set_exception_parameter_decl]
482 #define begin_handler_decl gnat_std_decls[(int) ADT_begin_handler_decl]
483 #define others_decl gnat_std_decls[(int) ADT_others_decl]
484 #define all_others_decl gnat_std_decls[(int) ADT_all_others_decl]
485 #define unhandled_others_decl gnat_std_decls[(int) ADT_unhandled_others_decl]
486 #define end_handler_decl gnat_std_decls[(int) ADT_end_handler_decl]
487 #define unhandled_except_decl gnat_std_decls[(int) ADT_unhandled_except_decl]
488 
489 /* Routines expected by the gcc back-end. They must have exactly the same
490    prototype and names as below.  */
491 
492 /* Return true if we are in the global binding level.  */
493 extern bool global_bindings_p (void);
494 
495 /* Enter and exit a new binding level.  */
496 extern void gnat_pushlevel (void);
497 extern void gnat_poplevel (void);
498 extern void gnat_zaplevel (void);
499 
500 /* Set SUPERCONTEXT of the BLOCK for the current binding level to FNDECL
501    and point FNDECL to this BLOCK.  */
502 extern void set_current_block_context (tree fndecl);
503 
504 /* Set the jmpbuf_decl for the current binding level to DECL.  */
505 extern void set_block_jmpbuf_decl (tree decl);
506 
507 /* Get the setjmp_decl, if any, for the current binding level.  */
508 extern tree get_block_jmpbuf_decl (void);
509 
510 /* Record DECL as belonging to the current lexical scope and use GNAT_NODE
511    for location information and flag propagation.  */
512 extern void gnat_pushdecl (tree decl, Node_Id gnat_node);
513 
514 /* Initialize the GCC support for exception handling.  */
515 extern void gnat_init_gcc_eh (void);
516 
517 /* Initialize the GCC support for floating-point operations.  */
518 extern void gnat_init_gcc_fp (void);
519 
520 /* Install the builtin functions we might need.  */
521 extern void gnat_install_builtins (void);
522 
523 /* Return an integer type with the number of bits of precision given by
524    PRECISION.  UNSIGNEDP is nonzero if the type is unsigned; otherwise
525    it is a signed type.  */
526 extern tree gnat_type_for_size (unsigned precision, int unsignedp);
527 
528 /* Return a data type that has machine mode MODE.  UNSIGNEDP selects
529    an unsigned type; otherwise a signed type is returned.  */
530 extern tree gnat_type_for_mode (machine_mode mode, int unsignedp);
531 
532 /* Perform final processing on global declarations.  */
533 extern void gnat_write_global_declarations (void);
534 
535 /* Return the signed or unsigned version of TYPE_NODE, a scalar type, the
536    signedness being specified by UNSIGNEDP.  */
537 extern tree gnat_signed_or_unsigned_type_for (int unsignedp, tree type_node);
538 
539 /* Return 1 if the types T1 and T2 are compatible, i.e. if they can be
540    transparently converted to each other.  */
541 extern int gnat_types_compatible_p (tree t1, tree t2);
542 
543 /* Return true if EXPR is a useless type conversion.  */
544 extern bool gnat_useless_type_conversion (tree expr);
545 
546 /* Return true if T, a {FUNCTION,METHOD}_TYPE, has the specified flags.  */
547 extern bool fntype_same_flags_p (const_tree, tree, bool, bool, bool);
548 
549 /* Create an expression whose value is that of EXPR,
550    converted to type TYPE.  The TREE_TYPE of the value
551    is always TYPE.  This function implements all reasonable
552    conversions; callers should filter out those that are
553    not permitted by the language being compiled.  */
554 extern tree convert (tree type, tree expr);
555 
556 /* Create an expression whose value is that of EXPR converted to the common
557    index type, which is sizetype.  */
558 extern tree convert_to_index_type (tree expr);
559 
560 /* Routines created solely for the tree translator's sake. Their prototypes
561    can be changed as desired.  */
562 
563 /* Initialize data structures of the utils.c module.  */
564 extern void init_gnat_utils (void);
565 
566 /* Destroy data structures of the utils.c module.  */
567 extern void destroy_gnat_utils (void);
568 
569 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
570    GNU_DECL is the GCC tree which is to be associated with
571    GNAT_ENTITY. Such gnu tree node is always an ..._DECL node.
572    If NO_CHECK is nonzero, the latter check is suppressed.
573    If GNU_DECL is zero, a previous association is to be reset.  */
574 extern void save_gnu_tree (Entity_Id gnat_entity, tree gnu_decl,
575                            bool no_check);
576 
577 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
578    Return the ..._DECL node that was associated with it.  If there is no tree
579    node associated with GNAT_ENTITY, abort.  */
580 extern tree get_gnu_tree (Entity_Id gnat_entity);
581 
582 /* Return nonzero if a GCC tree has been associated with GNAT_ENTITY.  */
583 extern bool present_gnu_tree (Entity_Id gnat_entity);
584 
585 /* Make a dummy type corresponding to GNAT_TYPE.  */
586 extern tree make_dummy_type (Entity_Id gnat_type);
587 
588 /* Return the dummy type that was made for GNAT_TYPE, if any.  */
589 extern tree get_dummy_type (Entity_Id gnat_type);
590 
591 /* Build dummy fat and thin pointer types whose designated type is specified
592    by GNAT_DESIG_TYPE/GNU_DESIG_TYPE and attach them to the latter.  */
593 extern void build_dummy_unc_pointer_types (Entity_Id gnat_desig_type,
594 					   tree gnu_desig_type);
595 
596 /* Record TYPE as a builtin type for Ada.  NAME is the name of the type.
597    ARTIFICIAL_P is true if the type was generated by the compiler.  */
598 extern void record_builtin_type (const char *name, tree type,
599 				 bool artificial_p);
600 
601 /* Finish constructing the character type CHAR_TYPE.  */
602 extern void finish_character_type (tree char_type);
603 
604 /* Given a record type RECORD_TYPE and a list of FIELD_DECL nodes FIELD_LIST,
605    finish constructing the record type as a fat pointer type.  */
606 extern void finish_fat_pointer_type (tree record_type, tree field_list);
607 
608 /* Given a record type RECORD_TYPE and a list of FIELD_DECL nodes FIELD_LIST,
609    finish constructing the record or union type.  If REP_LEVEL is zero, this
610    record has no representation clause and so will be entirely laid out here.
611    If REP_LEVEL is one, this record has a representation clause and has been
612    laid out already; only set the sizes and alignment.  If REP_LEVEL is two,
613    this record is derived from a parent record and thus inherits its layout;
614    only make a pass on the fields to finalize them.  DEBUG_INFO_P is true if
615    additional debug info needs to be output for this type.  */
616 extern void finish_record_type (tree record_type, tree field_list,
617 				int rep_level, bool debug_info_p);
618 
619 /* Wrap up compilation of RECORD_TYPE, i.e. output additional debug info
620    associated with it.  It need not be invoked directly in most cases as
621    finish_record_type takes care of doing so.  */
622 extern void rest_of_record_type_compilation (tree record_type);
623 
624 /* Append PARALLEL_TYPE on the chain of parallel types for TYPE.  */
625 extern void add_parallel_type (tree type, tree parallel_type);
626 
627 /* Return a copy of TYPE, but safe to modify in any way.  */
628 extern tree copy_type (tree type);
629 
630 /* Return a subtype of sizetype with range MIN to MAX and whose
631    TYPE_INDEX_TYPE is INDEX.  GNAT_NODE is used for the position
632    of the associated TYPE_DECL.  */
633 extern tree create_index_type (tree min, tree max, tree index,
634 			       Node_Id gnat_node);
635 
636 /* Return a subtype of TYPE with range MIN to MAX.  If TYPE is NULL,
637    sizetype is used.  */
638 extern tree create_range_type (tree type, tree min, tree max);
639 
640 /* Return an extra subtype of TYPE with range MIN to MAX.  */
641 extern tree create_extra_subtype (tree type, tree min, tree max);
642 
643 /* Return a TYPE_DECL node suitable for the TYPE_STUB_DECL field of TYPE.
644    NAME gives the name of the type to be used in the declaration.  */
645 extern tree create_type_stub_decl (tree name, tree type);
646 
647 /* Return a TYPE_DECL node for TYPE.  NAME gives the name of the type to be
648    used in the declaration.  ARTIFICIAL_P is true if the declaration was
649    generated by the compiler.  DEBUG_INFO_P is true if we need to write
650    debug information about this type.  GNAT_NODE is used for the position
651    of the decl.  */
652 extern tree create_type_decl (tree name, tree type, bool artificial_p,
653 			      bool debug_info_p, Node_Id gnat_node);
654 
655 /* Return a VAR_DECL or CONST_DECL node.
656 
657    NAME gives the name of the variable.  ASM_NAME is its assembler name
658    (if provided).  TYPE is its data type (a GCC ..._TYPE node).  INIT is
659    the GCC tree for an optional initial expression; NULL_TREE if none.
660 
661    CONST_FLAG is true if this variable is constant, in which case we might
662    return a CONST_DECL node unless CONST_DECL_ALLOWED_P is false.
663 
664    PUBLIC_FLAG is true if this is for a reference to a public entity or for a
665    definition to be made visible outside of the current compilation unit, for
666    instance variable definitions in a package specification.
667 
668    EXTERN_FLAG is true when processing an external variable declaration (as
669    opposed to a definition: no storage is to be allocated for the variable).
670 
671    STATIC_FLAG is only relevant when not at top level and indicates whether
672    to always allocate storage to the variable.
673 
674    VOLATILE_FLAG is true if this variable is declared as volatile.
675 
676    ARTIFICIAL_P is true if the variable was generated by the compiler.
677 
678    DEBUG_INFO_P is true if we need to write debug information for it.
679 
680    ATTR_LIST is the list of attributes to be attached to the variable.
681 
682    GNAT_NODE is used for the position of the decl.  */
683 extern tree create_var_decl (tree name, tree asm_name, tree type, tree init,
684 			     bool const_flag, bool public_flag,
685 			     bool extern_flag, bool static_flag,
686 			     bool volatile_flag,
687 			     bool artificial_p, bool debug_info_p,
688 			     struct attrib *attr_list, Node_Id gnat_node,
689 			     bool const_decl_allowed_p = true);
690 
691 /* Return a FIELD_DECL node.  NAME is the field's name, TYPE is its type and
692    RECORD_TYPE is the type of the enclosing record.  If SIZE is nonzero, it
693    is the specified size of the field.  If POS is nonzero, it is the bit
694    position.  PACKED is 1 if the enclosing record is packed, -1 if it has
695    Component_Alignment of Storage_Unit.  If ADDRESSABLE is nonzero, it
696    means we are allowed to take the address of the field; if it is negative,
697    we should not make a bitfield, which is used by make_aligning_type.  */
698 extern tree create_field_decl (tree name, tree type, tree record_type,
699 			       tree size, tree pos, int packed,
700 			       int addressable);
701 
702 /* Return a PARM_DECL node with NAME and TYPE.  */
703 extern tree create_param_decl (tree name, tree type);
704 
705 /* Return a LABEL_DECL with NAME.  GNAT_NODE is used for the position of
706    the decl.  */
707 extern tree create_label_decl (tree name, Node_Id gnat_node);
708 
709 /* Return a FUNCTION_DECL node.  NAME is the name of the subprogram, ASM_NAME
710    its assembler name, TYPE its type (a FUNCTION_TYPE node), PARAM_DECL_LIST
711    the list of its parameters (a list of PARM_DECL nodes chained through the
712    DECL_CHAIN field).
713 
714    INLINE_STATUS describes the inline flags to be set on the FUNCTION_DECL.
715 
716    PUBLIC_FLAG is true if this is for a reference to a public entity or for a
717    definition to be made visible outside of the current compilation unit.
718 
719    EXTERN_FLAG is true when processing an external subprogram declaration.
720 
721    ARTIFICIAL_P is true if the subprogram was generated by the compiler.
722 
723    DEBUG_INFO_P is true if we need to write debug information for it.
724 
725    DEFINITION is true if the subprogram is to be considered as a definition.
726 
727    ATTR_LIST is the list of attributes to be attached to the subprogram.
728 
729    GNAT_NODE is used for the position of the decl.  */
730 extern tree create_subprog_decl (tree name, tree asm_name, tree type,
731 				 tree param_decl_list,
732 				 enum inline_status_t inline_status,
733 				 bool public_flag, bool extern_flag,
734 				 bool artificial_p, bool debug_info_p,
735 				 bool definition, struct attrib *attr_list,
736 				 Node_Id gnat_node);
737 
738 /* Given a subprogram declaration DECL, its assembler name and its type,
739    finish constructing the subprogram declaration from ASM_NAME and TYPE.  */
740 extern void finish_subprog_decl (tree decl, tree asm_name, tree type);
741 
742 /* Process the attributes in ATTR_LIST for NODE, which is either a DECL or
743    a TYPE.  If IN_PLACE is true, the tree pointed to by NODE should not be
744    changed.  GNAT_NODE is used for the position of error messages.  */
745 extern void process_attributes (tree *node, struct attrib **attr_list,
746 				bool in_place, Node_Id gnat_node);
747 
748 /* Set up the framework for generating code for SUBPROG_DECL, a subprogram
749    body. This routine needs to be invoked before processing the declarations
750    appearing in the subprogram.  */
751 extern void begin_subprog_body (tree subprog_decl);
752 
753 /* Finish translating the current subprogram and set its BODY.  */
754 extern void end_subprog_body (tree body);
755 
756 /* Wrap up compilation of SUBPROG_DECL, a subprogram body.  */
757 extern void rest_of_subprog_body_compilation (tree subprog_decl);
758 
759 /* Build a template of type TEMPLATE_TYPE from the array bounds of ARRAY_TYPE.
760    EXPR is an expression that we can use to locate any PLACEHOLDER_EXPRs.
761    Return a constructor for the template.  */
762 extern tree build_template (tree template_type, tree array_type, tree expr);
763 
764 /* Build a type to be used to represent an aliased object whose nominal type
765    is an unconstrained array.  This consists of a RECORD_TYPE containing a
766    field of TEMPLATE_TYPE and a field of OBJECT_TYPE, which is an ARRAY_TYPE.
767    If ARRAY_TYPE is that of an unconstrained array, this is used to represent
768    an arbitrary unconstrained object.  Use NAME as the name of the record.
769    DEBUG_INFO_P is true if we need to write debug information for the type.  */
770 extern tree build_unc_object_type (tree template_type, tree object_type,
771 				   tree name, bool debug_info_p);
772 
773 /* Same as build_unc_object_type, but taking a thin or fat pointer type
774    instead of the template type.  */
775 extern tree build_unc_object_type_from_ptr (tree thin_fat_ptr_type,
776 					    tree object_type, tree name,
777 					    bool debug_info_p);
778 
779 /* Update anything previously pointing to OLD_TYPE to point to NEW_TYPE.  In
780    the normal case this is just two adjustments, but we have more to do
781    if NEW is an UNCONSTRAINED_ARRAY_TYPE.  */
782 extern void update_pointer_to (tree old_type, tree new_type);
783 
784 /* EXP is an expression for the size of an object.  If this size contains
785    discriminant references, replace them with the maximum (if MAX_P) or
786    minimum (if !MAX_P) possible value of the discriminant.  */
787 extern tree max_size (tree exp, bool max_p);
788 
789 /* Remove all conversions that are done in EXP.  This includes converting
790    from a padded type or to a left-justified modular type.  If TRUE_ADDRESS
791    is true, always return the address of the containing object even if
792    the address is not bit-aligned.  */
793 extern tree remove_conversions (tree exp, bool true_address);
794 
795 /* If EXP's type is an UNCONSTRAINED_ARRAY_TYPE, return an expression that
796    refers to the underlying array.  If its type has TYPE_CONTAINS_TEMPLATE_P,
797    likewise return an expression pointing to the underlying array.  */
798 extern tree maybe_unconstrained_array (tree exp);
799 
800 /* Return an expression that does an unchecked conversion of EXPR to TYPE.
801    If NOTRUNC_P is true, truncation operations should be suppressed.  */
802 extern tree unchecked_convert (tree type, tree expr, bool notrunc_p);
803 
804 /* Return the appropriate GCC tree code for the specified GNAT_TYPE,
805    the latter being a record type as predicated by Is_Record_Type.  */
806 extern enum tree_code tree_code_for_record_type (Entity_Id gnat_type);
807 
808 /* Return true if GNAT_TYPE is a "double" floating-point type, i.e. whose
809    size is equal to 64 bits, or an array of such a type.  Set ALIGN_CLAUSE
810    according to the presence of an alignment clause on the type or, if it
811    is an array, on the component type.  */
812 extern bool is_double_float_or_array (Entity_Id gnat_type,
813 				      bool *align_clause);
814 
815 /* Return true if GNAT_TYPE is a "double" or larger scalar type, i.e. whose
816    size is greater or equal to 64 bits, or an array of such a type.  Set
817    ALIGN_CLAUSE according to the presence of an alignment clause on the
818    type or, if it is an array, on the component type.  */
819 extern bool is_double_scalar_or_array (Entity_Id gnat_type,
820 				       bool *align_clause);
821 
822 /* Return true if GNU_TYPE is suitable as the type of a non-aliased
823    component of an aggregate type.  */
824 extern bool type_for_nonaliased_component_p (tree gnu_type);
825 
826 /* Return true if TYPE is a smaller form of ORIG_TYPE.  */
827 extern bool smaller_form_type_p (tree type, tree orig_type);
828 
829 /* Return the base type of TYPE.  */
830 extern tree get_base_type (tree type);
831 
832 /* EXP is a GCC tree representing an address.  See if we can find how
833    strictly the object at that address is aligned.   Return that alignment
834    strictly the object at that address is aligned.   Return that alignment
835    in bits.  If we don't know anything about the alignment, return 0.  */
836 extern unsigned int known_alignment (tree exp);
837 
838 /* Return true if VALUE is a multiple of FACTOR. FACTOR must be a power
839    of 2.  */
840 extern bool value_factor_p (tree value, HOST_WIDE_INT factor);
841 
842 /* Build an atomic load for the underlying atomic object in SRC.  SYNC is
843    true if the load requires synchronization.  */
844 extern tree build_atomic_load (tree src, bool sync);
845 
846 /* Build an atomic store from SRC to the underlying atomic object in DEST.
847    SYNC is true if the store requires synchronization.  */
848 extern tree build_atomic_store (tree dest, tree src, bool sync);
849 
850 /* Build a load-modify-store sequence from SRC to DEST.  GNAT_NODE is used for
851    the location of the sequence.  Note that, even if the load and the store are
852    both atomic, the sequence itself is not atomic.  */
853 extern tree build_load_modify_store (tree dest, tree src, Node_Id gnat_node);
854 
855 /* Make a binary operation of kind OP_CODE.  RESULT_TYPE is the type
856    desired for the result.  Usually the operation is to be performed
857    in that type.  For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
858    in which case the type to be used will be derived from the operands.
859    Don't fold the result if NO_FOLD is true.  */
860 extern tree build_binary_op (enum tree_code op_code, tree result_type,
861 			     tree left_operand, tree right_operand,
862 			     bool no_fold=false);
863 
864 /* Similar, but make unary operation.  */
865 extern tree build_unary_op (enum tree_code op_code, tree result_type,
866                             tree operand);
867 
868 /* Similar, but for COND_EXPR.  */
869 extern tree build_cond_expr (tree result_type, tree condition_operand,
870                              tree true_operand, tree false_operand);
871 
872 /* Similar, but for COMPOUND_EXPR.  */
873 extern tree build_compound_expr (tree result_type, tree stmt_operand,
874 				 tree expr_operand);
875 
876 /* Conveniently construct a function call expression.  FNDECL names the
877    function to be called, N is the number of arguments, and the "..."
878    parameters are the argument expressions.  Unlike build_call_expr
879    this doesn't fold the call, hence it will always return a CALL_EXPR.  */
880 extern tree build_call_n_expr (tree fndecl, int n, ...);
881 
882 /* Build a call to a function that raises an exception and passes file name
883    and line number, if requested.  MSG says which exception function to call.
884    GNAT_NODE is the node conveying the source location for which the error
885    should be signaled, or Empty in which case the error is signaled for the
886    current location.  KIND says which kind of exception node this is for,
887    among N_Raise_{Constraint,Storage,Program}_Error.  */
888 extern tree build_call_raise (int msg, Node_Id gnat_node, char kind);
889 
890 /* Similar to build_call_raise, with extra information about the column
891    where the check failed.  */
892 extern tree build_call_raise_column (int msg, Node_Id gnat_node, char kind);
893 
894 /* Similar to build_call_raise_column, for an index or range check exception ,
895    with extra information of the form "INDEX out of range FIRST..LAST".  */
896 extern tree build_call_raise_range (int msg, Node_Id gnat_node, char kind,
897 				    tree index, tree first, tree last);
898 
899 /* Return a CONSTRUCTOR of TYPE whose elements are V.  This is not the
900    same as build_constructor in the language-independent tree.c.  */
901 extern tree gnat_build_constructor (tree type, vec<constructor_elt, va_gc> *v);
902 
903 /* Return a COMPONENT_REF to access FIELD in RECORD, or NULL_EXPR and generate
904    a Constraint_Error if the field is not found in the record.  Don't fold the
905    result if NO_FOLD is true.  */
906 extern tree build_component_ref (tree record, tree field, bool no_fold);
907 
908 /* Build a GCC tree to call an allocation or deallocation function.
909    If GNU_OBJ is nonzero, it is an object to deallocate.  Otherwise,
910    generate an allocator.
911 
912    GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
913    object type, used to determine the to-be-honored address alignment.
914    GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
915    pool to use.  If not present, malloc and free are used.  GNAT_NODE is used
916    to provide an error location for restriction violation messages.  */
917 extern tree build_call_alloc_dealloc (tree gnu_obj, tree gnu_size,
918                                       tree gnu_type, Entity_Id gnat_proc,
919 				      Entity_Id gnat_pool, Node_Id gnat_node);
920 
921 /* Build a GCC tree to correspond to allocating an object of TYPE whose
922    initial value if INIT, if INIT is nonzero.  Convert the expression to
923    RESULT_TYPE, which must be some type of pointer.  Return the tree.
924 
925    GNAT_PROC and GNAT_POOL optionally give the procedure to call and
926    the storage pool to use.  GNAT_NODE is used to provide an error
927    location for restriction violation messages.  If IGNORE_INIT_TYPE is
928    true, ignore the type of INIT for the purpose of determining the size;
929    this will cause the maximum size to be allocated if TYPE is of
930    self-referential size.  */
931 extern tree build_allocator (tree type, tree init, tree result_type,
932                              Entity_Id gnat_proc, Entity_Id gnat_pool,
933                              Node_Id gnat_node, bool);
934 
935 /* Indicate that we need to take the address of T and that it therefore
936    should not be allocated in a register.  Returns true if successful.  */
937 extern bool gnat_mark_addressable (tree t);
938 
939 /* Save EXP for later use or reuse.  This is equivalent to save_expr in tree.c
940    but we know how to handle our own nodes.  */
941 extern tree gnat_save_expr (tree exp);
942 
943 /* Protect EXP for immediate reuse.  This is a variant of gnat_save_expr that
944    is optimized under the assumption that EXP's value doesn't change before
945    its subsequent reuse(s) except through its potential reevaluation.  */
946 extern tree gnat_protect_expr (tree exp);
947 
948 /* This is equivalent to stabilize_reference in tree.c but we know how to
949    handle our own nodes and we take extra arguments.  FORCE says whether to
950    force evaluation of everything in REF.  INIT is set to the first arm of
951    a COMPOUND_EXPR present in REF, if any.  */
952 extern tree gnat_stabilize_reference (tree ref, bool force, tree *init);
953 
954 /* Rewrite reference REF and call FUNC on each expression within REF in the
955    process.  DATA is passed unmodified to FUNC.  INIT is set to the first
956    arm of a COMPOUND_EXPR present in REF, if any.  */
957 typedef tree (*rewrite_fn) (tree, void *);
958 extern tree gnat_rewrite_reference (tree ref, rewrite_fn func, void *data,
959 				    tree *init);
960 
961 /* This is equivalent to get_inner_reference in expr.c but it returns the
962    ultimate containing object only if the reference (lvalue) is constant,
963    i.e. if it doesn't depend on the context in which it is evaluated.  */
964 extern tree get_inner_constant_reference (tree exp);
965 
966 /* Return true if EXPR is the addition or the subtraction of a constant and,
967    if so, set *ADD to the addend, *CST to the constant and *MINUS_P to true
968    if this is a subtraction.  */
969 extern bool is_simple_additive_expression (tree expr, tree *add, tree *cst,
970 					   bool *minus_p);
971 
972 /* If EXPR is an expression that is invariant in the current function, in the
973    sense that it can be evaluated anywhere in the function and any number of
974    times, return EXPR or an equivalent expression.  Otherwise return NULL.  */
975 extern tree gnat_invariant_expr (tree expr);
976 
977 /* Implementation of the builtin_function langhook.  */
978 extern tree gnat_builtin_function (tree decl);
979 
980 /* Search the chain of currently reachable declarations for a builtin
981    FUNCTION_DECL node corresponding to function NAME (an IDENTIFIER_NODE).
982    Return the first node found, if any, or NULL_TREE otherwise.  */
983 extern tree builtin_decl_for (tree name);
984 
985 /* GNU_TYPE is a type. Determine if it should be passed by reference by
986    default.  */
987 extern bool default_pass_by_ref (tree gnu_type);
988 
989 /* GNU_TYPE is the type of a subprogram parameter.  Determine from the type
990    if it should be passed by reference.  */
991 extern bool must_pass_by_ref (tree gnu_type);
992 
993 /* Return the size of the FP mode with precision PREC.  */
994 extern int fp_prec_to_size (int prec);
995 
996 /* Return the precision of the FP mode with size SIZE.  */
997 extern int fp_size_to_prec (int size);
998 
999 /* Return whether GNAT_NODE is a defining identifier for a renaming that comes
1000    from the parameter association for the instantiation of a generic.  We do
1001    not want to emit source location for them: the code generated for their
1002    initialization is likely to disturb debugging.  */
1003 extern bool renaming_from_instantiation_p (Node_Id gnat_node);
1004 
1005 /* Try to process all nodes in the deferred context queue.  Keep in the queue
1006    the ones that cannot be processed yet, remove the other ones.  If FORCE is
1007    true, force the processing for all nodes, use the global context when nodes
1008    don't have a GNU translation.  */
1009 extern void process_deferred_decl_context (bool force);
1010 
1011 /* Return the innermost scope, starting at GNAT_NODE, we are be interested in
1012    the debug info, or Empty if there is no such scope.  If not NULL, set
1013    IS_SUBPROGRAM to whether the returned entity is a subprogram.  */
1014 extern Entity_Id get_debug_scope (Node_Id gnat_node, bool *is_subprogram);
1015 
1016 /* Return whether EXPR, which is the renamed object in an object renaming
1017    declaration, can be materialized as a reference (REFERENCE_TYPE).  This
1018    should be synchronized with Exp_Dbug.Debug_Renaming_Declaration.  */
1019 extern bool can_materialize_object_renaming_p (Node_Id expr);
1020 
1021 #ifdef __cplusplus
1022 extern "C" {
1023 #endif
1024 
1025 /* These functions return the basic data type sizes and related parameters
1026    about the target machine.  */
1027 extern Pos get_target_bits_per_unit (void);
1028 extern Pos get_target_bits_per_word (void);
1029 extern Pos get_target_char_size (void);
1030 extern Pos get_target_wchar_t_size (void);
1031 extern Pos get_target_short_size (void);
1032 extern Pos get_target_int_size (void);
1033 extern Pos get_target_long_size (void);
1034 extern Pos get_target_long_long_size (void);
1035 extern Pos get_target_pointer_size (void);
1036 extern Pos get_target_maximum_default_alignment (void);
1037 extern Pos get_target_system_allocator_alignment (void);
1038 extern Pos get_target_maximum_allowed_alignment (void);
1039 extern Pos get_target_maximum_alignment (void);
1040 extern Nat get_target_float_words_be (void);
1041 extern Nat get_target_words_be (void);
1042 extern Nat get_target_bytes_be (void);
1043 extern Nat get_target_bits_be (void);
1044 extern Nat get_target_strict_alignment (void);
1045 extern Nat get_target_double_float_alignment (void);
1046 extern Nat get_target_double_scalar_alignment (void);
1047 
1048 /* This function is called by the front-end to enumerate all the supported
1049    modes for the machine, as well as some predefined C types.  */
1050 extern void enumerate_modes (void (*f) (const char *, int, int, int, int, int,
1051 					int, int));
1052 
1053 #ifdef __cplusplus
1054 }
1055 #endif
1056 
1057 /* If EXP's type is a VECTOR_TYPE, return EXP converted to the associated
1058    TYPE_REPRESENTATIVE_ARRAY.  */
1059 
1060 static inline tree
maybe_vector_array(tree exp)1061 maybe_vector_array (tree exp)
1062 {
1063   tree etype = TREE_TYPE (exp);
1064 
1065   if (VECTOR_TYPE_P (etype))
1066     exp = convert (TYPE_REPRESENTATIVE_ARRAY (etype), exp);
1067 
1068   return exp;
1069 }
1070 
1071 /* Return the smallest power of 2 larger than X.  */
1072 
1073 static inline unsigned HOST_WIDE_INT
ceil_pow2(unsigned HOST_WIDE_INT x)1074 ceil_pow2 (unsigned HOST_WIDE_INT x)
1075 {
1076   return (unsigned HOST_WIDE_INT) 1 << ceil_log2 (x);
1077 }
1078 
1079 /* Return true if EXP, a CALL_EXPR, is an atomic load.  */
1080 
1081 static inline bool
call_is_atomic_load(tree exp)1082 call_is_atomic_load (tree exp)
1083 {
1084   tree fndecl = get_callee_fndecl (exp);
1085 
1086   if (!(fndecl && fndecl_built_in_p (fndecl, BUILT_IN_NORMAL)))
1087     return false;
1088 
1089   enum built_in_function code = DECL_FUNCTION_CODE (fndecl);
1090   return BUILT_IN_ATOMIC_LOAD_N <= code && code <= BUILT_IN_ATOMIC_LOAD_16;
1091 }
1092 
1093 /* Return true if TYPE is padding a self-referential type.  */
1094 
1095 static inline bool
type_is_padding_self_referential(tree type)1096 type_is_padding_self_referential (tree type)
1097 {
1098   if (!TYPE_IS_PADDING_P (type))
1099     return false;
1100 
1101   return CONTAINS_PLACEHOLDER_P (DECL_SIZE (TYPE_FIELDS (type)));
1102 }
1103 
1104 /* Return true if a function returning TYPE doesn't return a fixed size.  */
1105 
1106 static inline bool
return_type_with_variable_size_p(tree type)1107 return_type_with_variable_size_p (tree type)
1108 {
1109   if (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1110     return true;
1111 
1112   /* Return true for an unconstrained type with default discriminant, see
1113      the E_Subprogram_Type case of gnat_to_gnu_entity.  */
1114   if (type_is_padding_self_referential (type))
1115     return true;
1116 
1117   return false;
1118 }
1119 
1120 /* Return the unsigned version of TYPE_NODE, a scalar type.  */
1121 
1122 static inline tree
gnat_unsigned_type_for(tree type_node)1123 gnat_unsigned_type_for (tree type_node)
1124 {
1125   return gnat_signed_or_unsigned_type_for (1, type_node);
1126 }
1127 
1128 /* Return the signed version of TYPE_NODE, a scalar type.  */
1129 
1130 static inline tree
gnat_signed_type_for(tree type_node)1131 gnat_signed_type_for (tree type_node)
1132 {
1133   return gnat_signed_or_unsigned_type_for (0, type_node);
1134 }
1135 
1136 /* Adjust the character type TYPE if need be.  */
1137 
1138 static inline tree
maybe_character_type(tree type)1139 maybe_character_type (tree type)
1140 {
1141   if (TYPE_STRING_FLAG (type) && !TYPE_UNSIGNED (type))
1142     type = gnat_unsigned_type_for (type);
1143 
1144   return type;
1145 }
1146 
1147 /* Adjust the character value EXPR if need be.  */
1148 
1149 static inline tree
maybe_character_value(tree expr)1150 maybe_character_value (tree expr)
1151 {
1152   tree type = TREE_TYPE (expr);
1153 
1154   if (TYPE_STRING_FLAG (type) && !TYPE_UNSIGNED (type))
1155     {
1156       type = gnat_unsigned_type_for (type);
1157       expr = convert (type, expr);
1158     }
1159 
1160   return expr;
1161 }
1162 
1163 /* Return the debug type of TYPE if it exists, otherwise TYPE itself.  */
1164 
1165 static inline tree
maybe_debug_type(tree type)1166 maybe_debug_type (tree type)
1167 {
1168   if (TYPE_CAN_HAVE_DEBUG_TYPE_P (type) && TYPE_DEBUG_TYPE (type))
1169     type = TYPE_DEBUG_TYPE (type);
1170 
1171   return type;
1172 }
1173 
1174 /* Like build_qualified_type, but TYPE_QUALS is added to the existing
1175    qualifiers on TYPE.  */
1176 
1177 static inline tree
change_qualified_type(tree type,int type_quals)1178 change_qualified_type (tree type, int type_quals)
1179 {
1180   /* Qualifiers must be put on the associated array type.  */
1181   if (TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)
1182     return type;
1183 
1184   return build_qualified_type (type, TYPE_QUALS (type) | type_quals);
1185 }
1186