gcc/ada/gcc-interface/gigi.h

   1 /****************************************************************************
   2  *                                                                          *
   3  *                         GNAT COMPILER COMPONENTS                         *
   4  *                                                                          *
   5  *                                 G I G I                                  *
   6  *                                                                          *
   7  *                              C Header File                               *
   8  *                                                                          *
   9  *          Copyright (C) 1992-2014, 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 nonzero if this call is intended for a definition.  This is
  38    used for separate compilation where it necessary to know whether an
  39    external declaration or a definition should be created if the GCC equivalent
  40    was not created previously.  The value of 1 is normally used for a nonzero
  41    DEFINITION, but a value of 2 is used in special circumstances, defined in
  42    the code.  */
  43 extern tree gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr,
  44                                 int definition);
  45
  46 /* Similar, but if the returned value is a COMPONENT_REF, return the
  47    FIELD_DECL.  */
  48 extern tree gnat_to_gnu_field_decl (Entity_Id gnat_entity);
  49
  50 /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type.  Return
  51    the GCC type corresponding to that entity.  */
  52 extern tree gnat_to_gnu_type (Entity_Id gnat_entity);
  53
  54 /* Start a new statement group chained to the previous group.  */
  55 extern void start_stmt_group (void);
  56
  57 /* Add GNU_STMT to the current statement group.  If it is an expression with
  58    no effects, it is ignored.  */
  59 extern void add_stmt (tree gnu_stmt);
  60
  61 /* Similar, but the statement is always added, regardless of side-effects.  */
  62 extern void add_stmt_force (tree gnu_stmt);
  63
  64 /* Like add_stmt, but set the location of GNU_STMT to that of GNAT_NODE.  */
  65 extern void add_stmt_with_node (tree gnu_stmt, Node_Id gnat_node);
  66
  67 /* Similar, but the statement is always added, regardless of side-effects.  */
  68 extern void add_stmt_with_node_force (tree gnu_stmt, Node_Id gnat_node);
  69
  70 /* Return code corresponding to the current code group.  It is normally
  71    a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
  72    BLOCK or cleanups were set.  */
  73 extern tree end_stmt_group (void);
  74
  75 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK.  */
  76 extern void set_block_for_group (tree);
  77
  78 /* Add a declaration statement for GNU_DECL to the current BLOCK_STMT node.
  79    Get SLOC from GNAT_ENTITY.  */
  80 extern void add_decl_expr (tree gnu_decl, Entity_Id gnat_entity);
  81
  82 /* Mark nodes rooted at T with TREE_VISITED and types as having their
  83    sized gimplified.  We use this to indicate all variable sizes and
  84    positions in global types may not be shared by any subprogram.  */
  85 extern void mark_visited (tree t);
  86
  87 /* This macro calls the above function but short-circuits the common
  88    case of a constant to save time and also checks for NULL.  */
  89
  90 #define MARK_VISITED(EXP)               \
  91 do {                                    \
  92   if((EXP) && !CONSTANT_CLASS_P (EXP))  \
  93     mark_visited (EXP);                 \
  94 } while (0)
  95
  96 /* Finalize the processing of From_Limited_With incomplete types.  */
  97 extern void finalize_from_limited_with (void);
  98
  99 /* Return the equivalent type to be used for GNAT_ENTITY, if it's a
 100    kind of type (such E_Task_Type) that has a different type which Gigi
 101    uses for its representation.  If the type does not have a special type
 102    for its representation, return GNAT_ENTITY.  If a type is supposed to
 103    exist, but does not, abort unless annotating types, in which case
 104    return Empty.   If GNAT_ENTITY is Empty, return Empty.  */
 105 extern Entity_Id Gigi_Equivalent_Type (Entity_Id gnat_entity);
 106
 107 /* Given GNAT_ENTITY, elaborate all expressions that are required to
 108    be elaborated at the point of its definition, but do nothing else.  */
 109 extern void elaborate_entity (Entity_Id gnat_entity);
 110
 111 /* Get the unpadded version of a GNAT type.  */
 112 extern tree get_unpadded_type (Entity_Id gnat_entity);
 113
 114 /* Return the DECL associated with the public subprogram GNAT_ENTITY but whose
 115    type has been changed to that of the parameterless procedure, except if an
 116    alias is already present, in which case it is returned instead.  */
 117 extern tree get_minimal_subprog_decl (Entity_Id gnat_entity);
 118
 119 /* Return whether the E_Subprogram_Type/E_Function/E_Procedure GNAT_ENTITY is
 120    a C++ imported method or equivalent.  */
 121 extern bool is_cplusplus_method (Entity_Id gnat_entity);
 122
 123 /* Create a record type that contains a SIZE bytes long field of TYPE with a
 124     starting bit position so that it is aligned to ALIGN bits, and leaving at
 125     least ROOM bytes free before the field.  BASE_ALIGN is the alignment the
 126     record is guaranteed to get.  GNAT_NODE is used for the position of the
 127     associated TYPE_DECL.  */
 128 extern tree make_aligning_type (tree type, unsigned int align, tree size,
 129                                 unsigned int base_align, int room, Node_Id);
 130
 131 /* TYPE is a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE that is being used
 132    as the field type of a packed record if IN_RECORD is true, or as the
 133    component type of a packed array if IN_RECORD is false.  See if we can
 134    rewrite it either as a type that has a non-BLKmode, which we can pack
 135    tighter in the packed record case, or as a smaller type.  If so, return
 136    the new type.  If not, return the original type.  */
 137 extern tree make_packable_type (tree type, bool in_record);
 138
 139 /* Given a type TYPE, return a new type whose size is appropriate for SIZE.
 140    If TYPE is the best type, return it.  Otherwise, make a new type.  We
 141    only support new integral and pointer types.  FOR_BIASED is true if
 142    we are making a biased type.  */
 143 extern tree make_type_from_size (tree type, tree size_tree, bool for_biased);
 144
 145 /* Ensure that TYPE has SIZE and ALIGN.  Make and return a new padded type
 146    if needed.  We have already verified that SIZE and ALIGN are large enough.
 147    GNAT_ENTITY is used to name the resulting record and to issue a warning.
 148    IS_COMPONENT_TYPE is true if this is being done for the component type of
 149    an array.  IS_USER_TYPE is true if the original type needs to be completed.
 150    DEFINITION is true if this type is being defined.  SET_RM_SIZE is true if
 151    the RM size of the resulting type is to be set to SIZE too.  */
 152 extern tree maybe_pad_type (tree type, tree size, unsigned int align,
 153                             Entity_Id gnat_entity, bool is_component_type,
 154                             bool is_user_type, bool definition,
 155                             bool set_rm_size);
 156
 157 /* Return a copy of the padded TYPE but with reverse storage order.  */
 158 extern tree set_reverse_storage_order_on_pad_type (tree type);
 159
 160 enum alias_set_op
 161 {
 162   ALIAS_SET_COPY,
 163   ALIAS_SET_SUBSET,
 164   ALIAS_SET_SUPERSET
 165 };
 166
 167 /* Relate the alias sets of GNU_NEW_TYPE and GNU_OLD_TYPE according to OP.
 168    If this is a multi-dimensional array type, do this recursively.
 169
 170    OP may be
 171    - ALIAS_SET_COPY:     the new set is made a copy of the old one.
 172    - ALIAS_SET_SUPERSET: the new set is made a superset of the old one.
 173    - ALIAS_SET_SUBSET:   the new set is made a subset of the old one.  */
 174 extern void relate_alias_sets (tree gnu_new_type, tree gnu_old_type,
 175                                enum alias_set_op op);
 176
 177 /* Given a GNU tree and a GNAT list of choices, generate an expression to test
 178    the value passed against the list of choices.  */
 179 extern tree choices_to_gnu (tree operand, Node_Id choices);
 180
 181 /* Given GNAT_ENTITY, an object (constant, variable, parameter, exception)
 182    and GNU_TYPE, its corresponding GCC type, set Esize and Alignment to the
 183    size and alignment used by Gigi.  Prefer SIZE over TYPE_SIZE if non-null.
 184    BY_REF is true if the object is used by reference.  */
 185 extern void annotate_object (Entity_Id gnat_entity, tree gnu_type, tree size,
 186                              bool by_ref);
 187
 188 /* Return the variant part of RECORD_TYPE, if any.  Otherwise return NULL.  */
 189 extern tree get_variant_part (tree record_type);
 190
 191 /* Given a type T, a FIELD_DECL F, and a replacement value R, return a new
 192    type with all size expressions that contain F updated by replacing F
 193    with R.  If F is NULL_TREE, always make a new RECORD_TYPE, even if
 194    nothing has changed.  */
 195 extern tree substitute_in_type (tree t, tree f, tree r);
 196
 197 /* Return the RM size of GNU_TYPE.  This is the actual number of bits
 198    needed to represent the object.  */
 199 extern tree rm_size (tree gnu_type);
 200
 201 /* Return the name to be used for GNAT_ENTITY.  If a type, create a
 202    fully-qualified name, possibly with type information encoding.
 203    Otherwise, return the name.  */
 204 extern tree get_entity_name (Entity_Id gnat_entity);
 205
 206 /* Return an identifier representing the external name to be used for
 207    GNAT_ENTITY.  If SUFFIX is specified, the name is followed by "___"
 208    and the specified suffix.  */
 209 extern tree create_concat_name (Entity_Id gnat_entity, const char *suffix);
 210
 211 /* Given GNU_NAME, an IDENTIFIER_NODE containing a name and SUFFIX, a
 212    string, return a new IDENTIFIER_NODE that is the concatenation of
 213    the name followed by "___" and the specified suffix.  */
 214 extern tree concat_name (tree gnu_name, const char *suffix);
 215
 216 /* Initialize data structures of the decl.c module.  */
 217 extern void init_gnat_decl (void);
 218
 219 /* Destroy data structures of the decl.c module.  */
 220 extern void destroy_gnat_decl (void);
 221
 222 /* Highest number in the front-end node table.  */
 223 extern int max_gnat_nodes;
 224
 225 /* Current node being treated, in case abort called.  */
 226 extern Node_Id error_gnat_node;
 227
 228 /* True when gigi is being called on an analyzed but unexpanded
 229    tree, and the only purpose of the call is to properly annotate
 230    types with representation information.  */
 231 extern bool type_annotate_only;
 232
 233 /* Current file name without path.  */
 234 extern const char *ref_filename;
 235
 236 /* This structure must be kept synchronized with Call_Back_End.  */
 237 struct File_Info_Type
 238 {
 239   File_Name_Type File_Name;
 240   Instance_Id    Instance;
 241   Nat            Num_Source_Lines;
 242 };
 243
 244 #ifdef __cplusplus
 245 extern "C" {
 246 #endif
 247
 248 /* This is the main program of the back-end.  It sets up all the table
 249    structures and then generates code.  */
 250 extern void gigi (Node_Id gnat_root,
 251                   int max_gnat_node,
 252                   int number_name ATTRIBUTE_UNUSED,
 253                   struct Node *nodes_ptr,
 254                   struct Flags *Flags_Ptr,
 255                   Node_Id *next_node_ptr,
 256                   Node_Id *prev_node_ptr,
 257                   struct Elist_Header *elists_ptr,
 258                   struct Elmt_Item *elmts_ptr,
 259                   struct String_Entry *strings_ptr,
 260                   Char_Code *strings_chars_ptr,
 261                   struct List_Header *list_headers_ptr,
 262                   Nat number_file,
 263                   struct File_Info_Type *file_info_ptr,
 264                   Entity_Id standard_boolean,
 265                   Entity_Id standard_integer,
 266                   Entity_Id standard_character,
 267                   Entity_Id standard_long_long_float,
 268                   Entity_Id standard_exception_type,
 269                   Int gigi_operating_mode);
 270
 271 #ifdef __cplusplus
 272 }
 273 #endif
 274
 275 /* GNAT_NODE is the root of some GNAT tree.  Return the root of the
 276    GCC tree corresponding to that GNAT tree.  Normally, no code is generated;
 277    we just return an equivalent tree which is used elsewhere to generate
 278    code.  */
 279 extern tree gnat_to_gnu (Node_Id gnat_node);
 280
 281 /* GNU_STMT is a statement.  We generate code for that statement.  */
 282 extern void gnat_expand_stmt (tree gnu_stmt);
 283
 284 /* Generate GIMPLE in place for the expression at *EXPR_P.  */
 285 extern int gnat_gimplify_expr (tree *expr_p, gimple_seq *pre_p,
 286                                gimple_seq *post_p ATTRIBUTE_UNUSED);
 287
 288 /* Do the processing for the declaration of a GNAT_ENTITY, a type.  If
 289    a separate Freeze node exists, delay the bulk of the processing.  Otherwise
 290    make a GCC type for GNAT_ENTITY and set up the correspondence.  */
 291 extern void process_type (Entity_Id gnat_entity);
 292
 293 /* Convert SLOC into LOCUS.  Return true if SLOC corresponds to a source code
 294    location and false if it doesn't.  In the former case, set the Gigi global
 295    variable REF_FILENAME to the simple debug file name as given by sinput.  */
 296 extern bool Sloc_to_locus (Source_Ptr Sloc, location_t *locus);
 297
 298 /* Post an error message.  MSG is the error message, properly annotated.
 299    NODE is the node at which to post the error and the node to use for the
 300    '&' substitution.  */
 301 extern void post_error (const char *msg, Node_Id node);
 302
 303 /* Similar to post_error, but NODE is the node at which to post the error and
 304    ENT is the node to use for the '&' substitution.  */
 305 extern void post_error_ne (const char *msg, Node_Id node, Entity_Id ent);
 306
 307 /* Similar to post_error_ne, but NUM is the number to use for the '^'.  */
 308 extern void post_error_ne_num (const char *msg, Node_Id node, Entity_Id ent,
 309                                int num);
 310
 311 /* Similar to post_error_ne, but T is a GCC tree representing the number to
 312    write.  If T represents a constant, the text inside curly brackets in
 313    MSG will be output (presumably including a '^').  Otherwise it will not
 314    be output and the text inside square brackets will be output instead.  */
 315 extern void post_error_ne_tree (const char *msg, Node_Id node, Entity_Id ent,
 316                                 tree t);
 317
 318 /* Similar to post_error_ne_tree, but NUM is a second integer to write.  */
 319 extern void post_error_ne_tree_2 (const char *msg, Node_Id node, Entity_Id ent,
 320                                   tree t, int num);
 321
 322 /* Return a label to branch to for the exception type in KIND or NULL_TREE
 323    if none.  */
 324 extern tree get_exception_label (char kind);
 325
 326 /* Return the decl for the current elaboration procedure.  */
 327 extern tree get_elaboration_procedure (void);
 328
 329 /* If nonzero, pretend we are allocating at global level.  */
 330 extern int force_global;
 331
 332 /* The default alignment of "double" floating-point types, i.e. floating
 333    point types whose size is equal to 64 bits, or 0 if this alignment is
 334    not specifically capped.  */
 335 extern int double_float_alignment;
 336
 337 /* The default alignment of "double" or larger scalar types, i.e. scalar
 338    types whose size is greater or equal to 64 bits, or 0 if this alignment
 339    is not specifically capped.  */
 340 extern int double_scalar_alignment;
 341
 342 /* True if floating-point arithmetics may use wider intermediate results.  */
 343 extern bool fp_arith_may_widen;
 344 \f
 345 /* Data structures used to represent attributes.  */
 346
 347 enum attr_type
 348 {
 349   ATTR_MACHINE_ATTRIBUTE,
 350   ATTR_LINK_ALIAS,
 351   ATTR_LINK_SECTION,
 352   ATTR_LINK_CONSTRUCTOR,
 353   ATTR_LINK_DESTRUCTOR,
 354   ATTR_THREAD_LOCAL_STORAGE,
 355   ATTR_WEAK_EXTERNAL
 356 };
 357
 358 struct attrib
 359 {
 360   struct attrib *next;
 361   enum attr_type type;
 362   tree name;
 363   tree args;
 364   Node_Id error_point;
 365 };
 366
 367 /* Table of machine-independent internal attributes.  */
 368 extern const struct attribute_spec gnat_internal_attribute_table[];
 369
 370 /* Define the entries in the standard data array.  */
 371 enum standard_datatypes
 372 {
 373   /* The longest floating-point type.  */
 374   ADT_longest_float_type,
 375
 376   /* The type of an exception.  */
 377   ADT_except_type,
 378
 379   /* Type declaration node  <==> typedef void *T */
 380   ADT_ptr_void_type,
 381
 382   /* Function type declaration -- void T() */
 383   ADT_void_ftype,
 384
 385   /* Type declaration node  <==> typedef void *T() */
 386   ADT_ptr_void_ftype,
 387
 388   /* Type declaration node  <==> typedef virtual void *T() */
 389   ADT_fdesc_type,
 390
 391   /* Null pointer for above type.  */
 392   ADT_null_fdesc,
 393
 394   /* Value 1 in signed bitsizetype.  */
 395   ADT_sbitsize_one_node,
 396
 397   /* Value BITS_PER_UNIT in signed bitsizetype.  */
 398   ADT_sbitsize_unit_node,
 399
 400   /* Function declaration nodes for run-time functions for allocating memory.
 401      Ada allocators cause calls to this function to be generated.  */
 402   ADT_malloc_decl,
 403
 404   /* Likewise for freeing memory.  */
 405   ADT_free_decl,
 406
 407   /* Function decl node for 64-bit multiplication with overflow checking.  */
 408   ADT_mulv64_decl,
 409
 410   /* Identifier for the name of the _Parent field in tagged record types.  */
 411   ADT_parent_name_id,
 412
 413   /* Identifier for the name of the Exception_Data type.  */
 414   ADT_exception_data_name_id,
 415
 416   /* Types and decls used by our temporary exception mechanism.  See
 417      init_gigi_decls for details.  */
 418   ADT_jmpbuf_type,
 419   ADT_jmpbuf_ptr_type,
 420   ADT_get_jmpbuf_decl,
 421   ADT_set_jmpbuf_decl,
 422   ADT_get_excptr_decl,
 423   ADT_setjmp_decl,
 424   ADT_longjmp_decl,
 425   ADT_update_setjmp_buf_decl,
 426   ADT_raise_nodefer_decl,
 427   ADT_reraise_zcx_decl,
 428   ADT_set_exception_parameter_decl,
 429   ADT_begin_handler_decl,
 430   ADT_end_handler_decl,
 431   ADT_unhandled_except_decl,
 432   ADT_others_decl,
 433   ADT_all_others_decl,
 434   ADT_unhandled_others_decl,
 435   ADT_LAST};
 436
 437 /* Define kind of exception information associated with raise statements.  */
 438 enum exception_info_kind
 439 {
 440   /* Simple exception information: file:line.  */
 441   exception_simple,
 442   /* Range exception information: file:line + index, first, last.  */
 443   exception_range,
 444   /* Column exception information: file:line:column.  */
 445   exception_column
 446 };
 447
 448 /* Define the inline status of a subprogram.  */
 449 enum inline_status_t
 450 {
 451   /* Inlining is suppressed for the subprogram.  */
 452   is_suppressed,
 453   /* No inlining is requested for the subprogram.  */
 454   is_disabled,
 455   /* Inlining is requested for the subprogram.  */
 456   is_enabled,
 457   /* Inlining is required for the subprogram.  */
 458   is_required
 459 };
 460
 461 extern GTY(()) tree gnat_std_decls[(int) ADT_LAST];
 462 extern GTY(()) tree gnat_raise_decls[(int) LAST_REASON_CODE + 1];
 463 extern GTY(()) tree gnat_raise_decls_ext[(int) LAST_REASON_CODE + 1];
 464
 465 #define longest_float_type_node gnat_std_decls[(int) ADT_longest_float_type]
 466 #define except_type_node gnat_std_decls[(int) ADT_except_type]
 467 #define ptr_void_type_node gnat_std_decls[(int) ADT_ptr_void_type]
 468 #define void_ftype gnat_std_decls[(int) ADT_void_ftype]
 469 #define ptr_void_ftype gnat_std_decls[(int) ADT_ptr_void_ftype]
 470 #define fdesc_type_node gnat_std_decls[(int) ADT_fdesc_type]
 471 #define null_fdesc_node gnat_std_decls[(int) ADT_null_fdesc]
 472 #define sbitsize_one_node gnat_std_decls[(int) ADT_sbitsize_one_node]
 473 #define sbitsize_unit_node gnat_std_decls[(int) ADT_sbitsize_unit_node]
 474 #define malloc_decl gnat_std_decls[(int) ADT_malloc_decl]
 475 #define free_decl gnat_std_decls[(int) ADT_free_decl]
 476 #define mulv64_decl gnat_std_decls[(int) ADT_mulv64_decl]
 477 #define parent_name_id gnat_std_decls[(int) ADT_parent_name_id]
 478 #define exception_data_name_id gnat_std_decls[(int) ADT_exception_data_name_id]
 479 #define jmpbuf_type gnat_std_decls[(int) ADT_jmpbuf_type]
 480 #define jmpbuf_ptr_type gnat_std_decls[(int) ADT_jmpbuf_ptr_type]
 481 #define get_jmpbuf_decl gnat_std_decls[(int) ADT_get_jmpbuf_decl]
 482 #define set_jmpbuf_decl gnat_std_decls[(int) ADT_set_jmpbuf_decl]
 483 #define get_excptr_decl gnat_std_decls[(int) ADT_get_excptr_decl]
 484 #define setjmp_decl gnat_std_decls[(int) ADT_setjmp_decl]
 485 #define longjmp_decl gnat_std_decls[(int) ADT_longjmp_decl]
 486 #define update_setjmp_buf_decl gnat_std_decls[(int) ADT_update_setjmp_buf_decl]
 487 #define raise_nodefer_decl gnat_std_decls[(int) ADT_raise_nodefer_decl]
 488 #define reraise_zcx_decl gnat_std_decls[(int) ADT_reraise_zcx_decl]
 489 #define set_exception_parameter_decl \
 490           gnat_std_decls[(int) ADT_set_exception_parameter_decl]
 491 #define begin_handler_decl gnat_std_decls[(int) ADT_begin_handler_decl]
 492 #define others_decl gnat_std_decls[(int) ADT_others_decl]
 493 #define all_others_decl gnat_std_decls[(int) ADT_all_others_decl]
 494 #define unhandled_others_decl gnat_std_decls[(int) ADT_unhandled_others_decl]
 495 #define end_handler_decl gnat_std_decls[(int) ADT_end_handler_decl]
 496 #define unhandled_except_decl gnat_std_decls[(int) ADT_unhandled_except_decl]
 497
 498 /* Routines expected by the gcc back-end. They must have exactly the same
 499    prototype and names as below.  */
 500
 501 /* Return true if we are in the global binding level.  */
 502 extern bool global_bindings_p (void);
 503
 504 /* Enter and exit a new binding level.  */
 505 extern void gnat_pushlevel (void);
 506 extern void gnat_poplevel (void);
 507 extern void gnat_zaplevel (void);
 508
 509 /* Set SUPERCONTEXT of the BLOCK for the current binding level to FNDECL
 510    and point FNDECL to this BLOCK.  */
 511 extern void set_current_block_context (tree fndecl);
 512
 513 /* Set the jmpbuf_decl for the current binding level to DECL.  */
 514 extern void set_block_jmpbuf_decl (tree decl);
 515
 516 /* Get the setjmp_decl, if any, for the current binding level.  */
 517 extern tree get_block_jmpbuf_decl (void);
 518
 519 /* Record DECL as belonging to the current lexical scope and use GNAT_NODE
 520    for location information and flag propagation.  */
 521 extern void gnat_pushdecl (tree decl, Node_Id gnat_node);
 522
 523 /* Initialize the GCC support for exception handling.  */
 524 extern void gnat_init_gcc_eh (void);
 525
 526 /* Initialize the GCC support for floating-point operations.  */
 527 extern void gnat_init_gcc_fp (void);
 528
 529 /* Install the builtin functions we might need.  */
 530 extern void gnat_install_builtins (void);
 531
 532 /* Return an integer type with the number of bits of precision given by
 533    PRECISION.  UNSIGNEDP is nonzero if the type is unsigned; otherwise
 534    it is a signed type.  */
 535 extern tree gnat_type_for_size (unsigned precision, int unsignedp);
 536
 537 /* Return a data type that has machine mode MODE.  UNSIGNEDP selects
 538    an unsigned type; otherwise a signed type is returned.  */
 539 extern tree gnat_type_for_mode (machine_mode mode, int unsignedp);
 540
 541 /* Emit debug info for all global variable declarations.  */
 542 extern void gnat_write_global_declarations (void);
 543
 544 /* Return the unsigned version of a TYPE_NODE, a scalar type.  */
 545 extern tree gnat_unsigned_type (tree type_node);
 546
 547 /* Return the signed version of a TYPE_NODE, a scalar type.  */
 548 extern tree gnat_signed_type (tree type_node);
 549
 550 /* Return 1 if the types T1 and T2 are compatible, i.e. if they can be
 551    transparently converted to each other.  */
 552 extern int gnat_types_compatible_p (tree t1, tree t2);
 553
 554 /* Return true if EXPR is a useless type conversion.  */
 555 extern bool gnat_useless_type_conversion (tree expr);
 556
 557 /* Return true if T, a FUNCTION_TYPE, has the specified list of flags.  */
 558 extern bool fntype_same_flags_p (const_tree, tree, bool, bool, bool);
 559
 560 /* Create an expression whose value is that of EXPR,
 561    converted to type TYPE.  The TREE_TYPE of the value
 562    is always TYPE.  This function implements all reasonable
 563    conversions; callers should filter out those that are
 564    not permitted by the language being compiled.  */
 565 extern tree convert (tree type, tree expr);
 566
 567 /* Create an expression whose value is that of EXPR converted to the common
 568    index type, which is sizetype.  */
 569 extern tree convert_to_index_type (tree expr);
 570
 571 /* Routines created solely for the tree translator's sake. Their prototypes
 572    can be changed as desired.  */
 573
 574 /* Initialize data structures of the utils.c module.  */
 575 extern void init_gnat_utils (void);
 576
 577 /* Destroy data structures of the utils.c module.  */
 578 extern void destroy_gnat_utils (void);
 579
 580 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
 581    GNU_DECL is the GCC tree which is to be associated with
 582    GNAT_ENTITY. Such gnu tree node is always an ..._DECL node.
 583    If NO_CHECK is nonzero, the latter check is suppressed.
 584    If GNU_DECL is zero, a previous association is to be reset.  */
 585 extern void save_gnu_tree (Entity_Id gnat_entity, tree gnu_decl,
 586                            bool no_check);
 587
 588 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
 589    Return the ..._DECL node that was associated with it.  If there is no tree
 590    node associated with GNAT_ENTITY, abort.  */
 591 extern tree get_gnu_tree (Entity_Id gnat_entity);
 592
 593 /* Return nonzero if a GCC tree has been associated with GNAT_ENTITY.  */
 594 extern bool present_gnu_tree (Entity_Id gnat_entity);
 595
 596 /* Make a dummy type corresponding to GNAT_TYPE.  */
 597 extern tree make_dummy_type (Entity_Id gnat_type);
 598
 599 /* Return the dummy type that was made for GNAT_TYPE, if any.  */
 600 extern tree get_dummy_type (Entity_Id gnat_type);
 601
 602 /* Build dummy fat and thin pointer types whose designated type is specified
 603    by GNAT_DESIG_TYPE/GNU_DESIG_TYPE and attach them to the latter.  */
 604 extern void build_dummy_unc_pointer_types (Entity_Id gnat_desig_type,
 605                                            tree gnu_desig_type);
 606
 607 /* Record TYPE as a builtin type for Ada.  NAME is the name of the type.
 608    ARTIFICIAL_P is true if it's a type that was generated by the compiler.  */
 609 extern void record_builtin_type (const char *name, tree type,
 610                                  bool artificial_p);
 611
 612 /* Given a record type RECORD_TYPE and a list of FIELD_DECL nodes FIELD_LIST,
 613    finish constructing the record type as a fat pointer type.  */
 614 extern void finish_fat_pointer_type (tree record_type, tree field_list);
 615
 616 /* Given a record type RECORD_TYPE and a list of FIELD_DECL nodes FIELD_LIST,
 617    finish constructing the record or union type.  If REP_LEVEL is zero, this
 618    record has no representation clause and so will be entirely laid out here.
 619    If REP_LEVEL is one, this record has a representation clause and has been
 620    laid out already; only set the sizes and alignment.  If REP_LEVEL is two,
 621    this record is derived from a parent record and thus inherits its layout;
 622    only make a pass on the fields to finalize them.  DEBUG_INFO_P is true if
 623    we need to write debug information about this type.  */
 624 extern void finish_record_type (tree record_type, tree field_list,
 625                                 int rep_level, bool debug_info_p);
 626
 627 /* Wrap up compilation of RECORD_TYPE, i.e. output all the debug information
 628    associated with it.  It need not be invoked directly in most cases since
 629    finish_record_type takes care of doing so, but this can be necessary if
 630    a parallel type is to be attached to the record type.  */
 631 extern void rest_of_record_type_compilation (tree record_type);
 632
 633 /* Append PARALLEL_TYPE on the chain of parallel types for TYPE.  */
 634 extern void add_parallel_type (tree type, tree parallel_type);
 635
 636 /* Return a FUNCTION_TYPE node.  RETURN_TYPE is the type returned by the
 637    subprogram.  If it is VOID_TYPE, then we are dealing with a procedure,
 638    otherwise we are dealing with a function.  PARAM_DECL_LIST is a list of
 639    PARM_DECL nodes that are the subprogram parameters.  CICO_LIST is the
 640    copy-in/copy-out list to be stored into the TYPE_CICO_LIST field.
 641    RETURN_UNCONSTRAINED_P is true if the function returns an unconstrained
 642    object.  RETURN_BY_DIRECT_REF_P is true if the function returns by direct
 643    reference.  RETURN_BY_INVISI_REF_P is true if the function returns by
 644    invisible reference.  */
 645 extern tree create_subprog_type (tree return_type, tree param_decl_list,
 646                                  tree cico_list, bool return_unconstrained_p,
 647                                  bool return_by_direct_ref_p,
 648                                  bool return_by_invisi_ref_p);
 649
 650 /* Return a copy of TYPE, but safe to modify in any way.  */
 651 extern tree copy_type (tree type);
 652
 653 /* Return a subtype of sizetype with range MIN to MAX and whose
 654    TYPE_INDEX_TYPE is INDEX.  GNAT_NODE is used for the position
 655    of the associated TYPE_DECL.  */
 656 extern tree create_index_type (tree min, tree max, tree index,
 657                                Node_Id gnat_node);
 658
 659 /* Return a subtype of TYPE with range MIN to MAX.  If TYPE is NULL,
 660    sizetype is used.  */
 661 extern tree create_range_type (tree type, tree min, tree max);
 662
 663 /* Return a TYPE_DECL node suitable for the TYPE_STUB_DECL field of a type.
 664    TYPE_NAME gives the name of the type and TYPE is a ..._TYPE node giving
 665    its data type.  */
 666 extern tree create_type_stub_decl (tree type_name, tree type);
 667
 668 /* Return a TYPE_DECL node.  TYPE_NAME gives the name of the type and TYPE
 669    is a ..._TYPE node giving its data type.  ARTIFICIAL_P is true if this
 670    is a declaration that was generated by the compiler.  DEBUG_INFO_P is
 671    true if we need to write debug information about this type.  GNAT_NODE
 672    is used for the position of the decl.  */
 673 extern tree create_type_decl (tree type_name, tree type, bool artificial_p,
 674                               bool debug_info_p, Node_Id gnat_node);
 675
 676 /* Return a VAR_DECL or CONST_DECL node.
 677
 678    VAR_NAME gives the name of the variable.  ASM_NAME is its assembler name
 679    (if provided).  TYPE is its data type (a GCC ..._TYPE node).  VAR_INIT is
 680    the GCC tree for an optional initial expression; NULL_TREE if none.
 681
 682    CONST_FLAG is true if this variable is constant, in which case we might
 683    return a CONST_DECL node unless CONST_DECL_ALLOWED_P is false.
 684
 685    PUBLIC_FLAG is true if this definition is to be made visible outside of
 686    the current compilation unit. This flag should be set when processing the
 687    variable definitions in a package specification.
 688
 689    EXTERN_FLAG is nonzero when processing an external variable declaration (as
 690    opposed to a definition: no storage is to be allocated for the variable).
 691
 692    STATIC_FLAG is only relevant when not at top level.  In that case
 693    it indicates whether to always allocate storage to the variable.
 694
 695    GNAT_NODE is used for the position of the decl.  */
 696 extern tree
 697 create_var_decl_1 (tree var_name, tree asm_name, tree type, tree var_init,
 698                    bool const_flag, bool public_flag, bool extern_flag,
 699                    bool static_flag, bool const_decl_allowed_p,
 700                    struct attrib *attr_list, Node_Id gnat_node);
 701
 702 /* Wrapper around create_var_decl_1 for cases where we don't care whether
 703    a VAR or a CONST decl node is created.  */
 704 #define create_var_decl(var_name, asm_name, type, var_init,     \
 705                         const_flag, public_flag, extern_flag,   \
 706                         static_flag, attr_list, gnat_node)      \
 707   create_var_decl_1 (var_name, asm_name, type, var_init,        \
 708                      const_flag, public_flag, extern_flag,      \
 709                      static_flag, true, attr_list, gnat_node)
 710
 711 /* Wrapper around create_var_decl_1 for cases where a VAR_DECL node is
 712    required.  The primary intent is for DECL_CONST_CORRESPONDING_VARs, which
 713    must be VAR_DECLs and on which we want TREE_READONLY set to have them
 714    possibly assigned to a readonly data section.  */
 715 #define create_true_var_decl(var_name, asm_name, type, var_init,        \
 716                              const_flag, public_flag, extern_flag,      \
 717                              static_flag, attr_list, gnat_node)         \
 718   create_var_decl_1 (var_name, asm_name, type, var_init,                \
 719                      const_flag, public_flag, extern_flag,              \
 720                      static_flag, false, attr_list, gnat_node)
 721
 722 /* Record DECL as a global renaming pointer.  */
 723 extern void record_global_renaming_pointer (tree decl);
 724
 725 /* Invalidate the global renaming pointers.  */
 726 extern void invalidate_global_renaming_pointers (void);
 727
 728 /* Return a FIELD_DECL node.  FIELD_NAME is the field's name, FIELD_TYPE is
 729    its type and RECORD_TYPE is the type of the enclosing record.  If SIZE is
 730    nonzero, it is the specified size of the field.  If POS is nonzero, it is
 731    the bit position.  PACKED is 1 if the enclosing record is packed, -1 if it
 732    has Component_Alignment of Storage_Unit.  If ADDRESSABLE is nonzero, it
 733    means we are allowed to take the address of the field; if it is negative,
 734    we should not make a bitfield, which is used by make_aligning_type.  */
 735 extern tree create_field_decl (tree field_name, tree field_type,
 736                                tree record_type, tree size, tree pos,
 737                                int packed, int addressable);
 738
 739 /* Return a PARM_DECL node.  PARAM_NAME is the name of the parameter and
 740    PARAM_TYPE is its type.  READONLY is true if the parameter is readonly
 741    (either an In parameter or an address of a pass-by-ref parameter).  */
 742 extern tree create_param_decl (tree param_name, tree param_type,
 743                                bool readonly);
 744
 745 /* Return a LABEL_DECL with LABEL_NAME.  GNAT_NODE is used for the position
 746    of the decl.  */
 747 extern tree create_label_decl (tree label_name, Node_Id gnat_node);
 748
 749 /* Return a FUNCTION_DECL node.  SUBPROG_NAME is the name of the subprogram,
 750    ASM_NAME is its assembler name, SUBPROG_TYPE is its type (a FUNCTION_TYPE
 751    node), PARAM_DECL_LIST is the list of the subprogram arguments (a list of
 752    PARM_DECL nodes chained through the DECL_CHAIN field).
 753
 754    INLINE_STATUS, PUBLIC_FLAG, EXTERN_FLAG, ARTIFICIAL_FLAG and ATTR_LIST are
 755    used to set the appropriate fields in the FUNCTION_DECL.  GNAT_NODE is
 756    used for the position of the decl.  */
 757 extern tree create_subprog_decl (tree subprog_name, tree asm_name,
 758                                  tree subprog_type, tree param_decl_list,
 759                                  enum inline_status_t inline_status,
 760                                  bool public_flag, bool extern_flag,
 761                                  bool artificial_flag,
 762                                  struct attrib *attr_list, Node_Id gnat_node);
 763
 764 /* Process the attributes in ATTR_LIST for NODE, which is either a DECL or
 765    a TYPE.  If IN_PLACE is true, the tree pointed to by NODE should not be
 766    changed.  GNAT_NODE is used for the position of error messages.  */
 767 extern void process_attributes (tree *node, struct attrib **attr_list,
 768                                 bool in_place, Node_Id gnat_node);
 769
 770 /* Set up the framework for generating code for SUBPROG_DECL, a subprogram
 771    body. This routine needs to be invoked before processing the declarations
 772    appearing in the subprogram.  */
 773 extern void begin_subprog_body (tree subprog_decl);
 774
 775 /* Finish translating the current subprogram and set its BODY.  */
 776 extern void end_subprog_body (tree body);
 777
 778 /* Wrap up compilation of SUBPROG_DECL, a subprogram body.  */
 779 extern void rest_of_subprog_body_compilation (tree subprog_decl);
 780
 781 /* Build a template of type TEMPLATE_TYPE from the array bounds of ARRAY_TYPE.
 782    EXPR is an expression that we can use to locate any PLACEHOLDER_EXPRs.
 783    Return a constructor for the template.  */
 784 extern tree build_template (tree template_type, tree array_type, tree expr);
 785
 786 /* Build a type to be used to represent an aliased object whose nominal type
 787    is an unconstrained array.  This consists of a RECORD_TYPE containing a
 788    field of TEMPLATE_TYPE and a field of OBJECT_TYPE, which is an ARRAY_TYPE.
 789    If ARRAY_TYPE is that of an unconstrained array, this is used to represent
 790    an arbitrary unconstrained object.  Use NAME as the name of the record.
 791    DEBUG_INFO_P is true if we need to write debug information for the type.  */
 792 extern tree build_unc_object_type (tree template_type, tree object_type,
 793                                    tree name, bool debug_info_p);
 794
 795 /* Same as build_unc_object_type, but taking a thin or fat pointer type
 796    instead of the template type.  */
 797 extern tree build_unc_object_type_from_ptr (tree thin_fat_ptr_type,
 798                                             tree object_type, tree name,
 799                                             bool debug_info_p);
 800
 801 /* Update anything previously pointing to OLD_TYPE to point to NEW_TYPE.  In
 802    the normal case this is just two adjustments, but we have more to do
 803    if NEW is an UNCONSTRAINED_ARRAY_TYPE.  */
 804 extern void update_pointer_to (tree old_type, tree new_type);
 805
 806 /* EXP is an expression for the size of an object.  If this size contains
 807    discriminant references, replace them with the maximum (if MAX_P) or
 808    minimum (if !MAX_P) possible value of the discriminant.  */
 809 extern tree max_size (tree exp, bool max_p);
 810
 811 /* Remove all conversions that are done in EXP.  This includes converting
 812    from a padded type or to a left-justified modular type.  If TRUE_ADDRESS
 813    is true, always return the address of the containing object even if
 814    the address is not bit-aligned.  */
 815 extern tree remove_conversions (tree exp, bool true_address);
 816
 817 /* If EXP's type is an UNCONSTRAINED_ARRAY_TYPE, return an expression that
 818    refers to the underlying array.  If its type has TYPE_CONTAINS_TEMPLATE_P,
 819    likewise return an expression pointing to the underlying array.  */
 820 extern tree maybe_unconstrained_array (tree exp);
 821
 822 /* Return an expression that does an unchecked conversion of EXPR to TYPE.
 823    If NOTRUNC_P is true, truncation operations should be suppressed.  */
 824 extern tree unchecked_convert (tree type, tree expr, bool notrunc_p);
 825
 826 /* Return the appropriate GCC tree code for the specified GNAT_TYPE,
 827    the latter being a record type as predicated by Is_Record_Type.  */
 828 extern enum tree_code tree_code_for_record_type (Entity_Id gnat_type);
 829
 830 /* Return true if GNAT_TYPE is a "double" floating-point type, i.e. whose
 831    size is equal to 64 bits, or an array of such a type.  Set ALIGN_CLAUSE
 832    according to the presence of an alignment clause on the type or, if it
 833    is an array, on the component type.  */
 834 extern bool is_double_float_or_array (Entity_Id gnat_type,
 835                                       bool *align_clause);
 836
 837 /* Return true if GNAT_TYPE is a "double" or larger scalar type, i.e. whose
 838    size is greater or equal to 64 bits, or an array of such a type.  Set
 839    ALIGN_CLAUSE according to the presence of an alignment clause on the
 840    type or, if it is an array, on the component type.  */
 841 extern bool is_double_scalar_or_array (Entity_Id gnat_type,
 842                                        bool *align_clause);
 843
 844 /* Return true if GNU_TYPE is suitable as the type of a non-aliased
 845    component of an aggregate type.  */
 846 extern bool type_for_nonaliased_component_p (tree gnu_type);
 847
 848 /* Return true if TYPE is a smaller form of ORIG_TYPE.  */
 849 extern bool smaller_form_type_p (tree type, tree orig_type);
 850
 851 /* Return the base type of TYPE.  */
 852 extern tree get_base_type (tree type);
 853
 854 /* EXP is a GCC tree representing an address.  See if we can find how
 855    strictly the object at that address is aligned.   Return that alignment
 856    strictly the object at that address is aligned.   Return that alignment
 857    in bits.  If we don't know anything about the alignment, return 0.  */
 858 extern unsigned int known_alignment (tree exp);
 859
 860 /* Return true if VALUE is a multiple of FACTOR. FACTOR must be a power
 861    of 2.  */
 862 extern bool value_factor_p (tree value, HOST_WIDE_INT factor);
 863
 864 /* Build an atomic load for the underlying atomic object in SRC.  */
 865 extern tree build_atomic_load (tree src);
 866
 867 /* Build an atomic store from SRC to the underlying atomic object in DEST.  */
 868 extern tree build_atomic_store (tree dest, tree src);
 869
 870 /* Make a binary operation of kind OP_CODE.  RESULT_TYPE is the type
 871    desired for the result.  Usually the operation is to be performed
 872    in that type.  For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
 873    in which case the type to be used will be derived from the operands.  */
 874 extern tree build_binary_op (enum tree_code op_code, tree result_type,
 875                              tree left_operand, tree right_operand);
 876
 877 /* Similar, but make unary operation.  */
 878 extern tree build_unary_op (enum tree_code op_code, tree result_type,
 879                             tree operand);
 880
 881 /* Similar, but for COND_EXPR.  */
 882 extern tree build_cond_expr (tree result_type, tree condition_operand,
 883                              tree true_operand, tree false_operand);
 884
 885 /* Similar, but for COMPOUND_EXPR.  */
 886 extern tree build_compound_expr (tree result_type, tree stmt_operand,
 887                                  tree expr_operand);
 888
 889 /* Conveniently construct a function call expression.  FNDECL names the
 890    function to be called, N is the number of arguments, and the "..."
 891    parameters are the argument expressions.  Unlike build_call_expr
 892    this doesn't fold the call, hence it will always return a CALL_EXPR.  */
 893 extern tree build_call_n_expr (tree fndecl, int n, ...);
 894
 895 /* Call a function that raises an exception and pass the line number and file
 896    name, if requested.  MSG says which exception function to call.
 897
 898    GNAT_NODE is the gnat node conveying the source location for which the
 899    error should be signaled, or Empty in which case the error is signaled on
 900    the current ref_file_name/input_line.
 901
 902    KIND says which kind of exception this is for
 903     (N_Raise_{Constraint,Storage,Program}_Error).  */
 904 extern tree build_call_raise (int msg, Node_Id gnat_node, char kind);
 905
 906 /* Similar to build_call_raise, for an index or range check exception as
 907    determined by MSG, with extra information generated of the form
 908    "INDEX out of range FIRST..LAST".  */
 909 extern tree build_call_raise_range (int msg, Node_Id gnat_node,
 910                                     tree index, tree first, tree last);
 911
 912 /* Similar to build_call_raise, with extra information about the column
 913    where the check failed.  */
 914 extern tree build_call_raise_column (int msg, Node_Id gnat_node);
 915
 916 /* Return a CONSTRUCTOR of TYPE whose elements are V.  This is not the
 917    same as build_constructor in the language-independent tree.c.  */
 918 extern tree gnat_build_constructor (tree type, vec<constructor_elt, va_gc> *v);
 919
 920 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
 921    an IDENTIFIER_NODE giving the name of the field, FIELD, a FIELD_DECL,
 922    for the field, or both.  Don't fold the result if NO_FOLD_P.  */
 923 extern tree build_component_ref (tree record_variable, tree component,
 924                                  tree field, bool no_fold_p);
 925
 926 /* Build a GCC tree to call an allocation or deallocation function.
 927    If GNU_OBJ is nonzero, it is an object to deallocate.  Otherwise,
 928    generate an allocator.
 929
 930    GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
 931    object type, used to determine the to-be-honored address alignment.
 932    GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
 933    pool to use.  If not present, malloc and free are used.  GNAT_NODE is used
 934    to provide an error location for restriction violation messages.  */
 935 extern tree build_call_alloc_dealloc (tree gnu_obj, tree gnu_size,
 936                                       tree gnu_type, Entity_Id gnat_proc,
 937                                       Entity_Id gnat_pool, Node_Id gnat_node);
 938
 939 /* Build a GCC tree to correspond to allocating an object of TYPE whose
 940    initial value if INIT, if INIT is nonzero.  Convert the expression to
 941    RESULT_TYPE, which must be some type of pointer.  Return the tree.
 942
 943    GNAT_PROC and GNAT_POOL optionally give the procedure to call and
 944    the storage pool to use.  GNAT_NODE is used to provide an error
 945    location for restriction violation messages.  If IGNORE_INIT_TYPE is
 946    true, ignore the type of INIT for the purpose of determining the size;
 947    this will cause the maximum size to be allocated if TYPE is of
 948    self-referential size.  */
 949 extern tree build_allocator (tree type, tree init, tree result_type,
 950                              Entity_Id gnat_proc, Entity_Id gnat_pool,
 951                              Node_Id gnat_node, bool);
 952
 953 /* Indicate that we need to take the address of T and that it therefore
 954    should not be allocated in a register.  Returns true if successful.  */
 955 extern bool gnat_mark_addressable (tree t);
 956
 957 /* Save EXP for later use or reuse.  This is equivalent to save_expr in tree.c
 958    but we know how to handle our own nodes.  */
 959 extern tree gnat_save_expr (tree exp);
 960
 961 /* Protect EXP for immediate reuse.  This is a variant of gnat_save_expr that
 962    is optimized under the assumption that EXP's value doesn't change before
 963    its subsequent reuse(s) except through its potential reevaluation.  */
 964 extern tree gnat_protect_expr (tree exp);
 965
 966 /* This is equivalent to stabilize_reference in tree.c but we know how to
 967    handle our own nodes and we take extra arguments.  FORCE says whether to
 968    force evaluation of everything.  We set SUCCESS to true unless we walk
 969    through something we don't know how to stabilize.  */
 970 extern tree gnat_stabilize_reference (tree ref, bool force, bool *success);
 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_generic_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 #ifdef __cplusplus
1012 extern "C" {
1013 #endif
1014
1015 /* These functions return the basic data type sizes and related parameters
1016    about the target machine.  */
1017 extern Pos get_target_bits_per_unit (void);
1018 extern Pos get_target_bits_per_word (void);
1019 extern Pos get_target_char_size (void);
1020 extern Pos get_target_wchar_t_size (void);
1021 extern Pos get_target_short_size (void);
1022 extern Pos get_target_int_size (void);
1023 extern Pos get_target_long_size (void);
1024 extern Pos get_target_long_long_size (void);
1025 extern Pos get_target_float_size (void);
1026 extern Pos get_target_double_size (void);
1027 extern Pos get_target_long_double_size (void);
1028 extern Pos get_target_pointer_size (void);
1029 extern Pos get_target_maximum_default_alignment (void);
1030 extern Pos get_target_system_allocator_alignment (void);
1031 extern Pos get_target_maximum_allowed_alignment (void);
1032 extern Pos get_target_maximum_alignment (void);
1033 extern Nat get_float_words_be (void);
1034 extern Nat get_words_be (void);
1035 extern Nat get_bytes_be (void);
1036 extern Nat get_bits_be (void);
1037 extern Nat get_target_strict_alignment (void);
1038 extern Nat get_target_double_float_alignment (void);
1039 extern Nat get_target_double_scalar_alignment (void);
1040
1041 /* This function is called by the front-end to enumerate all the supported
1042    modes for the machine, as well as some predefined C types.  */
1043 extern void enumerate_modes (void (*f) (const char *, int, int, int, int, int,
1044                                         int, int));
1045
1046 #ifdef __cplusplus
1047 }
1048 #endif
1049
1050 /* Convenient shortcuts.  */
1051 #define VECTOR_TYPE_P(TYPE) (TREE_CODE (TYPE) == VECTOR_TYPE)
1052
1053 /* If EXP's type is a VECTOR_TYPE, return EXP converted to the associated
1054    TYPE_REPRESENTATIVE_ARRAY.  */
1055
1056 static inline tree
1057 maybe_vector_array (tree exp)
1058 {
1059   tree etype = TREE_TYPE (exp);
1060
1061   if (VECTOR_TYPE_P (etype))
1062     exp = convert (TYPE_REPRESENTATIVE_ARRAY (etype), exp);
1063
1064   return exp;
1065 }
1066
1067 static inline unsigned HOST_WIDE_INT
1068 ceil_pow2 (unsigned HOST_WIDE_INT x)
1069 {
1070   return (unsigned HOST_WIDE_INT) 1 << (floor_log2 (x - 1) + 1);
1071 }