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) 1992-2010, 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 /* Wrap up compilation of T, a TYPE_DECL, possibly deferring it.  */
  55 extern void rest_of_type_decl_compilation (tree t);
  56
  57 /* Start a new statement group chained to the previous group.  */
  58 extern void start_stmt_group (void);
  59
  60 /* Add GNU_STMT to the current BLOCK_STMT node.  */
  61 extern void add_stmt (tree gnu_stmt);
  62
  63 /* Similar, but set the location of GNU_STMT to that of GNAT_NODE.  */
  64 extern void add_stmt_with_node (tree gnu_stmt, Node_Id gnat_node);
  65
  66 /* Return code corresponding to the current code group.  It is normally
  67    a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if
  68    BLOCK or cleanups were set.  */
  69 extern tree end_stmt_group (void);
  70
  71 /* Set the BLOCK node corresponding to the current code group to GNU_BLOCK.  */
  72 extern void set_block_for_group (tree);
  73
  74 /* Add a declaration statement for GNU_DECL to the current BLOCK_STMT node.
  75    Get SLOC from GNAT_ENTITY.  */
  76 extern void add_decl_expr (tree gnu_decl, Entity_Id gnat_entity);
  77
  78 /* Mark nodes rooted at T with TREE_VISITED and types as having their
  79    sized gimplified.  We use this to indicate all variable sizes and
  80    positions in global types may not be shared by any subprogram.  */
  81 extern void mark_visited (tree t);
  82
  83 /* This macro calls the above function but short-circuits the common
  84    case of a constant to save time and also checks for NULL.  */
  85
  86 #define MARK_VISITED(EXP)               \
  87 do {                                    \
  88   if((EXP) && !TREE_CONSTANT (EXP))     \
  89     mark_visited (EXP);                 \
  90 } while (0)
  91
  92 /* Finalize any From_With_Type incomplete types.  We do this after processing
  93    our compilation unit and after processing its spec, if this is a body.  */
  94 extern void finalize_from_with_types (void);
  95
  96 /* Return the equivalent type to be used for GNAT_ENTITY, if it's a
  97    kind of type (such E_Task_Type) that has a different type which Gigi
  98    uses for its representation.  If the type does not have a special type
  99    for its representation, return GNAT_ENTITY.  If a type is supposed to
 100    exist, but does not, abort unless annotating types, in which case
 101    return Empty.   If GNAT_ENTITY is Empty, return Empty.  */
 102 extern Entity_Id Gigi_Equivalent_Type (Entity_Id gnat_entity);
 103
 104 /* Given GNAT_ENTITY, elaborate all expressions that are required to
 105    be elaborated at the point of its definition, but do nothing else.  */
 106 extern void elaborate_entity (Entity_Id gnat_entity);
 107
 108 /* Mark GNAT_ENTITY as going out of scope at this point.  Recursively mark
 109    any entities on its entity chain similarly.  */
 110 extern void mark_out_of_scope (Entity_Id gnat_entity);
 111
 112 /* Get the unpadded version of a GNAT type.  */
 113 extern tree get_unpadded_type (Entity_Id gnat_entity);
 114
 115 /* Create a record type that contains a SIZE bytes long field of TYPE with a
 116     starting bit position so that it is aligned to ALIGN bits, and leaving at
 117     least ROOM bytes free before the field.  BASE_ALIGN is the alignment the
 118     record is guaranteed to get.  */
 119 extern tree make_aligning_type (tree type, unsigned int align, tree size,
 120                                 unsigned int base_align, int room);
 121
 122 /* Ensure that TYPE has SIZE and ALIGN.  Make and return a new padded type
 123    if needed.  We have already verified that SIZE and TYPE are large enough.
 124    GNAT_ENTITY is used to name the resulting record and to issue a warning.
 125    IS_COMPONENT_TYPE is true if this is being done for the component type
 126    of an array.  IS_USER_TYPE is true if we must complete the original type.
 127    DEFINITION is true if this type is being defined.  SAME_RM_SIZE is true
 128    if the RM size of the resulting type is to be set to SIZE too; otherwise,
 129    it's set to the RM size of the original type.  */
 130 extern tree maybe_pad_type (tree type, tree size, unsigned int align,
 131                             Entity_Id gnat_entity, bool is_component_type,
 132                             bool is_user_type, bool definition,
 133                             bool same_rm_size);
 134
 135 /* Given a GNU tree and a GNAT list of choices, generate an expression to test
 136    the value passed against the list of choices.  */
 137 extern tree choices_to_gnu (tree operand, Node_Id choices);
 138
 139 /* Given GNAT_ENTITY, an object (constant, variable, parameter, exception)
 140    and GNU_TYPE, its corresponding GCC type, set Esize and Alignment to the
 141    size and alignment used by Gigi.  Prefer SIZE over TYPE_SIZE if non-null.
 142    BY_REF is true if the object is used by reference.  */
 143 extern void annotate_object (Entity_Id gnat_entity, tree gnu_type, tree size,
 144                              bool by_ref);
 145
 146 /* Given a type T, a FIELD_DECL F, and a replacement value R, return a new
 147    type with all size expressions that contain F updated by replacing F
 148    with R.  If F is NULL_TREE, always make a new RECORD_TYPE, even if
 149    nothing has changed.  */
 150 extern tree substitute_in_type (tree t, tree f, tree r);
 151
 152 /* Return the RM size of GNU_TYPE.  This is the actual number of bits
 153    needed to represent the object.  */
 154 extern tree rm_size (tree gnu_type);
 155
 156 /* Return the name to be used for GNAT_ENTITY.  If a type, create a
 157    fully-qualified name, possibly with type information encoding.
 158    Otherwise, return the name.  */
 159 extern tree get_entity_name (Entity_Id gnat_entity);
 160
 161 /* Return an identifier representing the external name to be used for
 162    GNAT_ENTITY.  If SUFFIX is specified, the name is followed by "___"
 163    and the specified suffix.  */
 164 extern tree create_concat_name (Entity_Id gnat_entity, const char *suffix);
 165
 166 /* Given GNU_NAME, an IDENTIFIER_NODE containing a name and SUFFIX, a
 167    string, return a new IDENTIFIER_NODE that is the concatenation of
 168    the name followed by "___" and the specified suffix.  */
 169 extern tree concat_name (tree gnu_name, const char *suffix);
 170
 171 /* If true, then gigi is being called on an analyzed but unexpanded tree, and
 172    the only purpose of the call is to properly annotate types with
 173    representation information.  */
 174 extern bool type_annotate_only;
 175
 176 /* Current file name without path */
 177 extern const char *ref_filename;
 178
 179 /* This structure must be kept synchronized with Call_Back_End.  */
 180 struct File_Info_Type
 181 {
 182   File_Name_Type File_Name;
 183   Nat Num_Source_Lines;
 184 };
 185
 186 /* This is the main program of the back-end.  It sets up all the table
 187    structures and then generates code.
 188
 189    ??? Needs parameter descriptions  */
 190
 191 extern void gigi (Node_Id gnat_root, int max_gnat_node, int number_name,
 192                   struct Node *nodes_ptr, Node_Id *next_node_ptr,
 193                   Node_Id *prev_node_ptr, struct Elist_Header *elists_ptr,
 194                   struct Elmt_Item *elmts_ptr,
 195                   struct String_Entry *strings_ptr,
 196                   Char_Code *strings_chars_ptr,
 197                   struct List_Header *list_headers_ptr,
 198                   Nat number_file,
 199                   struct File_Info_Type *file_info_ptr,
 200                   Entity_Id standard_boolean,
 201                   Entity_Id standard_integer,
 202                   Entity_Id standard_long_long_float,
 203                   Entity_Id standard_exception_type,
 204                   Int gigi_operating_mode);
 205
 206 /* GNAT_NODE is the root of some GNAT tree.  Return the root of the
 207    GCC tree corresponding to that GNAT tree.  Normally, no code is generated;
 208    we just return an equivalent tree which is used elsewhere to generate
 209    code.  */
 210 extern tree gnat_to_gnu (Node_Id gnat_node);
 211
 212 /* GNU_STMT is a statement.  We generate code for that statement.  */
 213 extern void gnat_expand_stmt (tree gnu_stmt);
 214
 215 /* Generate GIMPLE in place for the expression at *EXPR_P.  */
 216 extern int gnat_gimplify_expr (tree *expr_p, gimple_seq *pre_p,
 217                                gimple_seq *post_p ATTRIBUTE_UNUSED);
 218
 219 /* Do the processing for the declaration of a GNAT_ENTITY, a type.  If
 220    a separate Freeze node exists, delay the bulk of the processing.  Otherwise
 221    make a GCC type for GNAT_ENTITY and set up the correspondence.  */
 222 extern void process_type (Entity_Id gnat_entity);
 223
 224 /* Convert SLOC into LOCUS.  Return true if SLOC corresponds to a source code
 225    location and false if it doesn't.  In the former case, set the Gigi global
 226    variable REF_FILENAME to the simple debug file name as given by sinput.  */
 227 extern bool Sloc_to_locus (Source_Ptr Sloc, location_t *locus);
 228
 229 /* Post an error message.  MSG is the error message, properly annotated.
 230    NODE is the node at which to post the error and the node to use for the
 231    "&" substitution.  */
 232 extern void post_error (const char *msg, Node_Id node);
 233
 234 /* Similar, but NODE is the node at which to post the error and ENT
 235    is the node to use for the "&" substitution.  */
 236 extern void post_error_ne (const char *msg, Node_Id node, Entity_Id ent);
 237
 238 /* Similar, but NODE is the node at which to post the error, ENT is the node
 239    to use for the "&" substitution, and N is the number to use for the ^.  */
 240 extern void post_error_ne_num (const char *msg, Node_Id node, Entity_Id ent,
 241                                int n);
 242
 243 /* Similar to post_error_ne_num, but T is a GCC tree representing the number
 244    to write.  If the tree represents a constant that fits within a
 245    host integer, the text inside curly brackets in MSG will be output
 246    (presumably including a '^').  Otherwise that text will not be output
 247    and the text inside square brackets will be output instead.  */
 248 extern void post_error_ne_tree (const char *msg, Node_Id node, Entity_Id ent,
 249                                 tree t);
 250
 251 /* Similar to post_error_ne_tree, except that NUM is a second
 252    integer to write in the message.  */
 253 extern void post_error_ne_tree_2 (const char *msg, Node_Id node, Entity_Id ent,
 254                                   tree t, int num);
 255
 256 /* Return a label to branch to for the exception type in KIND or NULL_TREE
 257    if none.  */
 258 extern tree get_exception_label (char kind);
 259
 260 /* Current node being treated, in case gigi_abort or Check_Elaboration_Code
 261    called.  */
 262 extern Node_Id error_gnat_node;
 263
 264 /* Highest number in the front-end node table.  */
 265 extern int max_gnat_nodes;
 266
 267 /* If nonzero, pretend we are allocating at global level.  */
 268 extern int force_global;
 269
 270 /* The default alignment of "double" floating-point types, i.e. floating
 271    point types whose size is equal to 64 bits, or 0 if this alignment is
 272    not specifically capped.  */
 273 extern int double_float_alignment;
 274
 275 /* The default alignment of "double" or larger scalar types, i.e. scalar
 276    types whose size is greater or equal to 64 bits, or 0 if this alignment
 277    is not specifically capped.  */
 278 extern int double_scalar_alignment;
 279
 280 /* Standard data type sizes.  Most of these are not used.  */
 281
 282 #ifndef CHAR_TYPE_SIZE
 283 #define CHAR_TYPE_SIZE BITS_PER_UNIT
 284 #endif
 285
 286 #ifndef SHORT_TYPE_SIZE
 287 #define SHORT_TYPE_SIZE (BITS_PER_UNIT * MIN ((UNITS_PER_WORD + 1) / 2, 2))
 288 #endif
 289
 290 #ifndef INT_TYPE_SIZE
 291 #define INT_TYPE_SIZE BITS_PER_WORD
 292 #endif
 293
 294 #ifndef LONG_TYPE_SIZE
 295 #define LONG_TYPE_SIZE BITS_PER_WORD
 296 #endif
 297
 298 #ifndef LONG_LONG_TYPE_SIZE
 299 #define LONG_LONG_TYPE_SIZE (BITS_PER_WORD * 2)
 300 #endif
 301
 302 #ifndef FLOAT_TYPE_SIZE
 303 #define FLOAT_TYPE_SIZE BITS_PER_WORD
 304 #endif
 305
 306 #ifndef DOUBLE_TYPE_SIZE
 307 #define DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
 308 #endif
 309
 310 #ifndef LONG_DOUBLE_TYPE_SIZE
 311 #define LONG_DOUBLE_TYPE_SIZE (BITS_PER_WORD * 2)
 312 #endif
 313
 314 /* The choice of SIZE_TYPE here is very problematic.  We need a signed
 315    type whose bit width is Pmode.  Assume "long" is such a type here.  */
 316 #undef SIZE_TYPE
 317 #define SIZE_TYPE "long int"
 318 \f
 319 /* Data structures used to represent attributes.  */
 320
 321 enum attr_type
 322 {
 323   ATTR_MACHINE_ATTRIBUTE,
 324   ATTR_LINK_ALIAS,
 325   ATTR_LINK_SECTION,
 326   ATTR_LINK_CONSTRUCTOR,
 327   ATTR_LINK_DESTRUCTOR,
 328   ATTR_THREAD_LOCAL_STORAGE,
 329   ATTR_WEAK_EXTERNAL
 330 };
 331
 332 struct attrib
 333 {
 334   struct attrib *next;
 335   enum attr_type type;
 336   tree name;
 337   tree args;
 338   Node_Id error_point;
 339 };
 340
 341 /* Table of machine-independent internal attributes.  */
 342 extern const struct attribute_spec gnat_internal_attribute_table[];
 343
 344 /* Define the entries in the standard data array.  */
 345 enum standard_datatypes
 346 {
 347   /* The longest floating-point type.  */
 348   ADT_longest_float_type,
 349
 350   /* The type of an exception.  */
 351   ADT_except_type,
 352
 353   /* Type declaration node  <==> typedef void *T */
 354   ADT_ptr_void_type,
 355
 356   /* Function type declaration -- void T() */
 357   ADT_void_ftype,
 358
 359   /* Type declaration node  <==> typedef void *T() */
 360   ADT_ptr_void_ftype,
 361
 362   /* Type declaration node  <==> typedef virtual void *T() */
 363   ADT_fdesc_type,
 364
 365   /* Null pointer for above type */
 366   ADT_null_fdesc,
 367
 368   /* Function declaration nodes for run-time functions for allocating memory.
 369      Ada allocators cause calls to these functions to be generated.  Malloc32
 370      is used only on 64bit systems needing to allocate 32bit memory.  */
 371   ADT_malloc_decl,
 372   ADT_malloc32_decl,
 373
 374   /* Likewise for freeing memory.  */
 375   ADT_free_decl,
 376
 377   /* Function decl node for 64-bit multiplication with overflow checking */
 378   ADT_mulv64_decl,
 379
 380   /* Types and decls used by our temporary exception mechanism.  See
 381      init_gigi_decls for details.  */
 382   ADT_jmpbuf_type,
 383   ADT_jmpbuf_ptr_type,
 384   ADT_get_jmpbuf_decl,
 385   ADT_set_jmpbuf_decl,
 386   ADT_get_excptr_decl,
 387   ADT_setjmp_decl,
 388   ADT_longjmp_decl,
 389   ADT_update_setjmp_buf_decl,
 390   ADT_raise_nodefer_decl,
 391   ADT_begin_handler_decl,
 392   ADT_end_handler_decl,
 393   ADT_others_decl,
 394   ADT_all_others_decl,
 395   ADT_LAST};
 396
 397 extern GTY(()) tree gnat_std_decls[(int) ADT_LAST];
 398 extern GTY(()) tree gnat_raise_decls[(int) LAST_REASON_CODE + 1];
 399
 400 #define longest_float_type_node gnat_std_decls[(int) ADT_longest_float_type]
 401 #define except_type_node gnat_std_decls[(int) ADT_except_type]
 402 #define ptr_void_type_node gnat_std_decls[(int) ADT_ptr_void_type]
 403 #define void_ftype gnat_std_decls[(int) ADT_void_ftype]
 404 #define ptr_void_ftype gnat_std_decls[(int) ADT_ptr_void_ftype]
 405 #define fdesc_type_node gnat_std_decls[(int) ADT_fdesc_type]
 406 #define null_fdesc_node gnat_std_decls[(int) ADT_null_fdesc]
 407 #define malloc_decl gnat_std_decls[(int) ADT_malloc_decl]
 408 #define malloc32_decl gnat_std_decls[(int) ADT_malloc32_decl]
 409 #define free_decl gnat_std_decls[(int) ADT_free_decl]
 410 #define mulv64_decl gnat_std_decls[(int) ADT_mulv64_decl]
 411 #define jmpbuf_type gnat_std_decls[(int) ADT_jmpbuf_type]
 412 #define jmpbuf_ptr_type gnat_std_decls[(int) ADT_jmpbuf_ptr_type]
 413 #define get_jmpbuf_decl gnat_std_decls[(int) ADT_get_jmpbuf_decl]
 414 #define set_jmpbuf_decl gnat_std_decls[(int) ADT_set_jmpbuf_decl]
 415 #define get_excptr_decl gnat_std_decls[(int) ADT_get_excptr_decl]
 416 #define setjmp_decl gnat_std_decls[(int) ADT_setjmp_decl]
 417 #define longjmp_decl gnat_std_decls[(int) ADT_longjmp_decl]
 418 #define update_setjmp_buf_decl gnat_std_decls[(int) ADT_update_setjmp_buf_decl]
 419 #define raise_nodefer_decl gnat_std_decls[(int) ADT_raise_nodefer_decl]
 420 #define begin_handler_decl gnat_std_decls[(int) ADT_begin_handler_decl]
 421 #define others_decl gnat_std_decls[(int) ADT_others_decl]
 422 #define all_others_decl gnat_std_decls[(int) ADT_all_others_decl]
 423 #define end_handler_decl gnat_std_decls[(int) ADT_end_handler_decl]
 424
 425 /* Routines expected by the gcc back-end. They must have exactly the same
 426    prototype and names as below.  */
 427
 428 /* Returns nonzero if we are currently in the global binding level.  */
 429 extern int global_bindings_p (void);
 430
 431 /* Enter and exit a new binding level.  */
 432 extern void gnat_pushlevel (void);
 433 extern void gnat_poplevel (void);
 434
 435 /* Set SUPERCONTEXT of the BLOCK for the current binding level to FNDECL
 436    and point FNDECL to this BLOCK.  */
 437 extern void set_current_block_context (tree fndecl);
 438
 439 /* Set the jmpbuf_decl for the current binding level to DECL.  */
 440 extern void set_block_jmpbuf_decl (tree decl);
 441
 442 /* Get the setjmp_decl, if any, for the current binding level.  */
 443 extern tree get_block_jmpbuf_decl (void);
 444
 445 /* Records a ..._DECL node DECL as belonging to the current lexical scope
 446    and uses GNAT_NODE for location information.  */
 447 extern void gnat_pushdecl (tree decl, Node_Id gnat_node);
 448
 449 extern void gnat_init_decl_processing (void);
 450 extern void gnat_init_gcc_eh (void);
 451 extern void gnat_install_builtins (void);
 452
 453 /* Return an integer type with the number of bits of precision given by
 454    PRECISION.  UNSIGNEDP is nonzero if the type is unsigned; otherwise
 455    it is a signed type.  */
 456 extern tree gnat_type_for_size (unsigned precision, int unsignedp);
 457
 458 /* Return a data type that has machine mode MODE.  UNSIGNEDP selects
 459    an unsigned type; otherwise a signed type is returned.  */
 460 extern tree gnat_type_for_mode (enum machine_mode mode, int unsignedp);
 461
 462 /* Emit debug info for all global variable declarations.  */
 463 extern void gnat_write_global_declarations (void);
 464
 465 /* Return the unsigned version of a TYPE_NODE, a scalar type.  */
 466 extern tree gnat_unsigned_type (tree type_node);
 467
 468 /* Return the signed version of a TYPE_NODE, a scalar type.  */
 469 extern tree gnat_signed_type (tree type_node);
 470
 471 /* Return 1 if the types T1 and T2 are compatible, i.e. if they can be
 472    transparently converted to each other.  */
 473 extern int gnat_types_compatible_p (tree t1, tree t2);
 474
 475 /* Create an expression whose value is that of EXPR,
 476    converted to type TYPE.  The TREE_TYPE of the value
 477    is always TYPE.  This function implements all reasonable
 478    conversions; callers should filter out those that are
 479    not permitted by the language being compiled.  */
 480 extern tree convert (tree type, tree expr);
 481
 482 /* Routines created solely for the tree translator's sake. Their prototypes
 483    can be changed as desired.  */
 484
 485 /* Initialize the association of GNAT nodes to GCC trees.  */
 486 extern void init_gnat_to_gnu (void);
 487
 488 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
 489    GNU_DECL is the GCC tree which is to be associated with
 490    GNAT_ENTITY. Such gnu tree node is always an ..._DECL node.
 491    If NO_CHECK is nonzero, the latter check is suppressed.
 492    If GNU_DECL is zero, a previous association is to be reset.  */
 493 extern void save_gnu_tree (Entity_Id gnat_entity, tree gnu_decl,
 494                            bool no_check);
 495
 496 /* GNAT_ENTITY is a GNAT tree node for a defining identifier.
 497    Return the ..._DECL node that was associated with it.  If there is no tree
 498    node associated with GNAT_ENTITY, abort.  */
 499 extern tree get_gnu_tree (Entity_Id gnat_entity);
 500
 501 /* Return nonzero if a GCC tree has been associated with GNAT_ENTITY.  */
 502 extern bool present_gnu_tree (Entity_Id gnat_entity);
 503
 504 /* Initialize the association of GNAT nodes to GCC trees as dummies.  */
 505 extern void init_dummy_type (void);
 506
 507 /* Make a dummy type corresponding to GNAT_TYPE.  */
 508 extern tree make_dummy_type (Entity_Id gnat_type);
 509
 510 /* Record TYPE as a builtin type for Ada.  NAME is the name of the type.  */
 511 extern void record_builtin_type (const char *name, tree type);
 512
 513 /* Given a record type RECORD_TYPE and a list of FIELD_DECL nodes FIELD_LIST,
 514    finish constructing the record or union type.  If REP_LEVEL is zero, this
 515    record has no representation clause and so will be entirely laid out here.
 516    If REP_LEVEL is one, this record has a representation clause and has been
 517    laid out already; only set the sizes and alignment.  If REP_LEVEL is two,
 518    this record is derived from a parent record and thus inherits its layout;
 519    only make a pass on the fields to finalize them.  DEBUG_INFO_P is true if
 520    we need to write debug information about this type.  */
 521 extern void finish_record_type (tree record_type, tree field_list,
 522                                 int rep_level, bool debug_info_p);
 523
 524 /* Wrap up compilation of RECORD_TYPE, i.e. output all the debug information
 525    associated with it.  It need not be invoked directly in most cases since
 526    finish_record_type takes care of doing so, but this can be necessary if
 527    a parallel type is to be attached to the record type.  */
 528 extern void rest_of_record_type_compilation (tree record_type);
 529
 530 /* Append PARALLEL_TYPE on the chain of parallel types for decl.  */
 531 extern void add_parallel_type (tree decl, tree parallel_type);
 532
 533 /* Return the parallel type associated to a type, if any.  */
 534 extern tree get_parallel_type (tree type);
 535
 536 /* Return a FUNCTION_TYPE node.  RETURN_TYPE is the type returned by the
 537    subprogram.  If it is VOID_TYPE, then we are dealing with a procedure,
 538    otherwise we are dealing with a function.  PARAM_DECL_LIST is a list of
 539    PARM_DECL nodes that are the subprogram parameters.  CICO_LIST is the
 540    copy-in/copy-out list to be stored into the TYPE_CICO_LIST field.
 541    RETURN_UNCONSTRAINED_P is true if the function returns an unconstrained
 542    object.  RETURN_BY_DIRECT_REF_P is true if the function returns by direct
 543    reference.  RETURN_BY_INVISI_REF_P is true if the function returns by
 544    invisible reference.  */
 545 extern tree create_subprog_type (tree return_type, tree param_decl_list,
 546                                  tree cico_list, bool return_unconstrained_p,
 547                                  bool return_by_direct_ref_p,
 548                                  bool return_by_invisi_ref_p);
 549
 550 /* Return a copy of TYPE, but safe to modify in any way.  */
 551 extern tree copy_type (tree type);
 552
 553 /* Return a subtype of sizetype with range MIN to MAX and whose
 554    TYPE_INDEX_TYPE is INDEX.  GNAT_NODE is used for the position
 555    of the associated TYPE_DECL.  */
 556 extern tree create_index_type (tree min, tree max, tree index,
 557                                Node_Id gnat_node);
 558
 559 /* Return a subtype of TYPE with range MIN to MAX.  If TYPE is NULL,
 560    sizetype is used.  */
 561 extern tree create_range_type (tree type, tree min, tree max);
 562
 563 /* Return a TYPE_DECL node suitable for the TYPE_STUB_DECL field of a type.
 564    TYPE_NAME gives the name of the type and TYPE is a ..._TYPE node giving
 565    its data type.  */
 566 extern tree create_type_stub_decl (tree type_name, tree type);
 567
 568 /* Return a TYPE_DECL node.  TYPE_NAME gives the name of the type and TYPE
 569    is a ..._TYPE node giving its data type.  ARTIFICIAL_P is true if this
 570    is a declaration that was generated by the compiler.  DEBUG_INFO_P is
 571    true if we need to write debug information about this type.  GNAT_NODE
 572    is used for the position of the decl.  */
 573 extern tree create_type_decl (tree type_name, tree type,
 574                               struct attrib *attr_list,
 575                               bool artificial_p, bool debug_info_p,
 576                               Node_Id gnat_node);
 577
 578 /* Return a VAR_DECL or CONST_DECL node.
 579
 580    VAR_NAME gives the name of the variable.  ASM_NAME is its assembler name
 581    (if provided).  TYPE is its data type (a GCC ..._TYPE node).  VAR_INIT is
 582    the GCC tree for an optional initial expression; NULL_TREE if none.
 583
 584    CONST_FLAG is true if this variable is constant, in which case we might
 585    return a CONST_DECL node unless CONST_DECL_ALLOWED_P is false.
 586
 587    PUBLIC_FLAG is true if this definition is to be made visible outside of
 588    the current compilation unit. This flag should be set when processing the
 589    variable definitions in a package specification.
 590
 591    EXTERN_FLAG is nonzero when processing an external variable declaration (as
 592    opposed to a definition: no storage is to be allocated for the variable).
 593
 594    STATIC_FLAG is only relevant when not at top level.  In that case
 595    it indicates whether to always allocate storage to the variable.
 596
 597    GNAT_NODE is used for the position of the decl.  */
 598 extern tree
 599 create_var_decl_1 (tree var_name, tree asm_name, tree type, tree var_init,
 600                    bool const_flag, bool public_flag, bool extern_flag,
 601                    bool static_flag, bool const_decl_allowed_p,
 602                    struct attrib *attr_list, Node_Id gnat_node);
 603
 604 /* Wrapper around create_var_decl_1 for cases where we don't care whether
 605    a VAR or a CONST decl node is created.  */
 606 #define create_var_decl(var_name, asm_name, type, var_init,     \
 607                         const_flag, public_flag, extern_flag,   \
 608                         static_flag, attr_list, gnat_node)      \
 609   create_var_decl_1 (var_name, asm_name, type, var_init,        \
 610                      const_flag, public_flag, extern_flag,      \
 611                      static_flag, true, attr_list, gnat_node)
 612
 613 /* Wrapper around create_var_decl_1 for cases where a VAR_DECL node is
 614    required.  The primary intent is for DECL_CONST_CORRESPONDING_VARs, which
 615    must be VAR_DECLs and on which we want TREE_READONLY set to have them
 616    possibly assigned to a readonly data section.  */
 617 #define create_true_var_decl(var_name, asm_name, type, var_init,        \
 618                              const_flag, public_flag, extern_flag,      \
 619                              static_flag, attr_list, gnat_node)         \
 620   create_var_decl_1 (var_name, asm_name, type, var_init,                \
 621                      const_flag, public_flag, extern_flag,              \
 622                      static_flag, false, attr_list, gnat_node)
 623
 624 /* Given a DECL and ATTR_LIST, apply the listed attributes.  */
 625 extern void process_attributes (tree decl, struct attrib *attr_list);
 626
 627 /* Record DECL as a global renaming pointer.  */
 628 extern void record_global_renaming_pointer (tree decl);
 629
 630 /* Invalidate the global renaming pointers.  */
 631 extern void invalidate_global_renaming_pointers (void);
 632
 633 /* Return a FIELD_DECL node.  FIELD_NAME is the field's name, FIELD_TYPE is
 634    its type and RECORD_TYPE is the type of the enclosing record.  PACKED is
 635    1 if the enclosing record is packed, -1 if it has Component_Alignment of
 636    Storage_Unit.  If SIZE is nonzero, it is the specified size of the field.
 637    If POS is nonzero, it is the bit position.  If ADDRESSABLE is nonzero, it
 638    means we are allowed to take the address of the field; if it is negative,
 639    we should not make a bitfield, which is used by make_aligning_type.  */
 640 extern tree create_field_decl (tree field_name, tree field_type,
 641                                tree record_type, int packed, tree size,
 642                                tree pos, int addressable);
 643
 644 /* Returns a PARM_DECL node. PARAM_NAME is the name of the parameter,
 645    PARAM_TYPE is its type.  READONLY is true if the parameter is
 646    readonly (either an In parameter or an address of a pass-by-ref
 647    parameter).  */
 648 extern tree create_param_decl (tree param_name, tree param_type,
 649                                bool readonly);
 650
 651 /* Returns a FUNCTION_DECL node.  SUBPROG_NAME is the name of the subprogram,
 652    ASM_NAME is its assembler name, SUBPROG_TYPE is its type (a FUNCTION_TYPE
 653    node), PARAM_DECL_LIST is the list of the subprogram arguments (a list of
 654    PARM_DECL nodes chained through the TREE_CHAIN field).
 655
 656    INLINE_FLAG, PUBLIC_FLAG, EXTERN_FLAG, and ATTR_LIST are used to set the
 657    appropriate fields in the FUNCTION_DECL.  GNAT_NODE gives the location.  */
 658 extern tree create_subprog_decl (tree subprog_name, tree asm_name,
 659                                  tree subprog_type, tree param_decl_list,
 660                                  bool inlinee_flag, bool public_flag,
 661                                  bool extern_flag,
 662                                  struct attrib *attr_list, Node_Id gnat_node);
 663
 664 /* Returns a LABEL_DECL node for LABEL_NAME.  */
 665 extern tree create_label_decl (tree label_name);
 666
 667 /* Set up the framework for generating code for SUBPROG_DECL, a subprogram
 668    body. This routine needs to be invoked before processing the declarations
 669    appearing in the subprogram.  */
 670 extern void begin_subprog_body (tree subprog_decl);
 671
 672 /* Finish the definition of the current subprogram BODY and finalize it.  */
 673 extern void end_subprog_body (tree body);
 674
 675 /* Build a template of type TEMPLATE_TYPE from the array bounds of ARRAY_TYPE.
 676    EXPR is an expression that we can use to locate any PLACEHOLDER_EXPRs.
 677    Return a constructor for the template.  */
 678 extern tree build_template (tree template_type, tree array_type, tree expr);
 679
 680 /* Build a 64bit VMS descriptor from a Mechanism_Type, which must specify
 681    a descriptor type, and the GCC type of an object.  Each FIELD_DECL
 682    in the type contains in its DECL_INITIAL the expression to use when
 683    a constructor is made for the type.  GNAT_ENTITY is a gnat node used
 684    to print out an error message if the mechanism cannot be applied to
 685    an object of that type and also for the name.  */
 686 extern tree build_vms_descriptor (tree type, Mechanism_Type mech,
 687                                   Entity_Id gnat_entity);
 688
 689 /* Build a 32bit VMS descriptor from a Mechanism_Type. See above.  */
 690 extern tree build_vms_descriptor32 (tree type, Mechanism_Type mech,
 691                                   Entity_Id gnat_entity);
 692
 693 /* Build a stub for the subprogram specified by the GCC tree GNU_SUBPROG
 694    and the GNAT node GNAT_SUBPROG.  */
 695 extern void build_function_stub (tree gnu_subprog, Entity_Id gnat_subprog);
 696
 697 /* Build a type to be used to represent an aliased object whose nominal
 698    type is an unconstrained array.  This consists of a RECORD_TYPE containing
 699    a field of TEMPLATE_TYPE and a field of OBJECT_TYPE, which is an
 700    ARRAY_TYPE.  If ARRAY_TYPE is that of the unconstrained array, this
 701    is used to represent an arbitrary unconstrained object.  Use NAME
 702    as the name of the record.  */
 703 extern tree build_unc_object_type (tree template_type, tree object_type,
 704                                    tree name);
 705
 706 /* Same as build_unc_object_type, but taking a thin or fat pointer type
 707    instead of the template type.  */
 708 extern tree build_unc_object_type_from_ptr (tree thin_fat_ptr_type,
 709                                             tree object_type, tree name);
 710
 711 /* Shift the component offsets within an unconstrained object TYPE to make it
 712    suitable for use as a designated type for thin pointers.  */
 713 extern void shift_unc_components_for_thin_pointers (tree type);
 714
 715 /* Update anything previously pointing to OLD_TYPE to point to NEW_TYPE.  In
 716    the normal case this is just two adjustments, but we have more to do
 717    if NEW is an UNCONSTRAINED_ARRAY_TYPE.  */
 718 extern void update_pointer_to (tree old_type, tree new_type);
 719
 720 /* EXP is an expression for the size of an object.  If this size contains
 721    discriminant references, replace them with the maximum (if MAX_P) or
 722    minimum (if !MAX_P) possible value of the discriminant.  */
 723 extern tree max_size (tree exp, bool max_p);
 724
 725 /* Remove all conversions that are done in EXP.  This includes converting
 726    from a padded type or to a left-justified modular type.  If TRUE_ADDRESS
 727    is true, always return the address of the containing object even if
 728    the address is not bit-aligned.  */
 729 extern tree remove_conversions (tree exp, bool true_address);
 730
 731 /* If EXP's type is an UNCONSTRAINED_ARRAY_TYPE, return an expression that
 732    refers to the underlying array.  If its type has TYPE_CONTAINS_TEMPLATE_P,
 733    likewise return an expression pointing to the underlying array.  */
 734 extern tree maybe_unconstrained_array (tree exp);
 735
 736 /* If EXP's type is a VECTOR_TYPE, return EXP converted to the associated
 737    TYPE_REPRESENTATIVE_ARRAY.  */
 738 extern tree maybe_vector_array (tree exp);
 739
 740 /* Return an expression that does an unchecked conversion of EXPR to TYPE.
 741    If NOTRUNC_P is true, truncation operations should be suppressed.  */
 742 extern tree unchecked_convert (tree type, tree expr, bool notrunc_p);
 743
 744 /* Return the appropriate GCC tree code for the specified GNAT_TYPE,
 745    the latter being a record type as predicated by Is_Record_Type.  */
 746 extern enum tree_code tree_code_for_record_type (Entity_Id gnat_type);
 747
 748 /* Return true if GNAT_TYPE is a "double" floating-point type, i.e. whose
 749    size is equal to 64 bits, or an array of such a type.  Set ALIGN_CLAUSE
 750    according to the presence of an alignment clause on the type or, if it
 751    is an array, on the component type.  */
 752 extern bool is_double_float_or_array (Entity_Id gnat_type,
 753                                       bool *align_clause);
 754
 755 /* Return true if GNAT_TYPE is a "double" or larger scalar type, i.e. whose
 756    size is greater or equal to 64 bits, or an array of such a type.  Set
 757    ALIGN_CLAUSE according to the presence of an alignment clause on the
 758    type or, if it is an array, on the component type.  */
 759 extern bool is_double_scalar_or_array (Entity_Id gnat_type,
 760                                        bool *align_clause);
 761
 762 /* Return true if GNU_TYPE is suitable as the type of a non-aliased
 763    component of an aggregate type.  */
 764 extern bool type_for_nonaliased_component_p (tree gnu_type);
 765
 766 /* Return the base type of TYPE.  */
 767 extern tree get_base_type (tree type);
 768
 769 /* EXP is a GCC tree representing an address.  See if we can find how
 770    strictly the object at that address is aligned.   Return that alignment
 771    strictly the object at that address is aligned.   Return that alignment
 772    in bits.  If we don't know anything about the alignment, return 0.  */
 773 extern unsigned int known_alignment (tree exp);
 774
 775 /* Return true if VALUE is a multiple of FACTOR. FACTOR must be a power
 776    of 2.  */
 777 extern bool value_factor_p (tree value, HOST_WIDE_INT factor);
 778
 779 /* Make a binary operation of kind OP_CODE.  RESULT_TYPE is the type
 780    desired for the result.  Usually the operation is to be performed
 781    in that type.  For MODIFY_EXPR and ARRAY_REF, RESULT_TYPE may be 0
 782    in which case the type to be used will be derived from the operands.  */
 783 extern tree build_binary_op (enum tree_code op_code, tree result_type,
 784                              tree left_operand, tree right_operand);
 785
 786 /* Similar, but make unary operation.  */
 787 extern tree build_unary_op (enum tree_code op_code, tree result_type,
 788                             tree operand);
 789
 790 /* Similar, but for COND_EXPR.  */
 791 extern tree build_cond_expr (tree result_type, tree condition_operand,
 792                              tree true_operand, tree false_operand);
 793
 794 /* Similar, but for RETURN_EXPR.  */
 795 extern tree build_return_expr (tree ret_obj, tree ret_val);
 796
 797 /* Build a CALL_EXPR to call FUNDECL with one argument, ARG.  Return
 798    the CALL_EXPR.  */
 799 extern tree build_call_1_expr (tree fundecl, tree arg);
 800
 801 /* Build a CALL_EXPR to call FUNDECL with two argument, ARG1 & ARG2.  Return
 802    the CALL_EXPR.  */
 803 extern tree build_call_2_expr (tree fundecl, tree arg1, tree arg2);
 804
 805 /* Likewise to call FUNDECL with no arguments.  */
 806 extern tree build_call_0_expr (tree fundecl);
 807
 808 /* Call a function that raises an exception and pass the line number and file
 809    name, if requested.  MSG says which exception function to call.
 810
 811    GNAT_NODE is the gnat node conveying the source location for which the
 812    error should be signaled, or Empty in which case the error is signaled on
 813    the current ref_file_name/input_line.
 814
 815    KIND says which kind of exception this is for
 816     (N_Raise_{Constraint,Storage,Program}_Error).  */
 817 extern tree build_call_raise (int msg, Node_Id gnat_node, char kind);
 818
 819 /* Return a CONSTRUCTOR of TYPE whose list is LIST.  This is not the
 820    same as build_constructor in the language-independent tree.c.  */
 821 extern tree gnat_build_constructor (tree type, tree list);
 822
 823 /* Return a COMPONENT_REF to access a field that is given by COMPONENT,
 824    an IDENTIFIER_NODE giving the name of the field, FIELD, a FIELD_DECL,
 825    for the field, or both.  Don't fold the result if NO_FOLD_P.  */
 826 extern tree build_component_ref (tree record_variable, tree component,
 827                                  tree field, bool no_fold_p);
 828
 829 /* Build a GCC tree to call an allocation or deallocation function.
 830    If GNU_OBJ is nonzero, it is an object to deallocate.  Otherwise,
 831    generate an allocator.
 832
 833    GNU_SIZE is the number of bytes to allocate and GNU_TYPE is the contained
 834    object type, used to determine the to-be-honored address alignment.
 835    GNAT_PROC, if present, is a procedure to call and GNAT_POOL is the storage
 836    pool to use.  If not present, malloc and free are used.  GNAT_NODE is used
 837    to provide an error location for restriction violation messages.  */
 838 extern tree build_call_alloc_dealloc (tree gnu_obj, tree gnu_size,
 839                                       tree gnu_type, Entity_Id gnat_proc,
 840                                       Entity_Id gnat_pool, Node_Id gnat_node);
 841
 842 /* Build a GCC tree to correspond to allocating an object of TYPE whose
 843    initial value if INIT, if INIT is nonzero.  Convert the expression to
 844    RESULT_TYPE, which must be some type of pointer.  Return the tree.
 845
 846    GNAT_PROC and GNAT_POOL optionally give the procedure to call and
 847    the storage pool to use.  GNAT_NODE is used to provide an error
 848    location for restriction violation messages.  If IGNORE_INIT_TYPE is
 849    true, ignore the type of INIT for the purpose of determining the size;
 850    this will cause the maximum size to be allocated if TYPE is of
 851    self-referential size.  */
 852 extern tree build_allocator (tree type, tree init, tree result_type,
 853                              Entity_Id gnat_proc, Entity_Id gnat_pool,
 854                              Node_Id gnat_node, bool);
 855
 856 /* Fill in a VMS descriptor for EXPR and return a constructor for it.
 857    GNAT_FORMAL is how we find the descriptor record. GNAT_ACTUAL is how
 858    we derive the source location on a C_E */
 859 extern tree fill_vms_descriptor (tree expr, Entity_Id gnat_formal,
 860                                  Node_Id gnat_actual);
 861
 862 /* Indicate that we need to take the address of T and that it therefore
 863    should not be allocated in a register.  Returns true if successful.  */
 864 extern bool gnat_mark_addressable (tree t);
 865
 866 /* Save EXP for later use or reuse.  This is equivalent to save_expr in tree.c
 867    but we know how to handle our own nodes.  */
 868 extern tree gnat_save_expr (tree exp);
 869
 870 /* Protect EXP for immediate reuse.  This is a variant of gnat_save_expr that
 871    is optimized under the assumption that EXP's value doesn't change before
 872    its subsequent reuse(s) except through its potential reevaluation.  */
 873 extern tree gnat_protect_expr (tree exp);
 874
 875 /* This is equivalent to stabilize_reference in tree.c but we know how to
 876    handle our own nodes and we take extra arguments.  FORCE says whether to
 877    force evaluation of everything.  We set SUCCESS to true unless we walk
 878    through something we don't know how to stabilize.  */
 879 extern tree gnat_stabilize_reference (tree ref, bool force, bool *success);
 880
 881 /* Implementation of the builtin_function langhook.  */
 882 extern tree gnat_builtin_function (tree decl);
 883
 884 /* Search the chain of currently reachable declarations for a builtin
 885    FUNCTION_DECL node corresponding to function NAME (an IDENTIFIER_NODE).
 886    Return the first node found, if any, or NULL_TREE otherwise.  */
 887 extern tree builtin_decl_for (tree name);
 888
 889 /* GNU_TYPE is a type. Determine if it should be passed by reference by
 890    default.  */
 891 extern bool default_pass_by_ref (tree gnu_type);
 892
 893 /* GNU_TYPE is the type of a subprogram parameter.  Determine from the type
 894    if it should be passed by reference.  */
 895 extern bool must_pass_by_ref (tree gnu_type);
 896
 897 /* This function is called by the front end to enumerate all the supported
 898    modes for the machine.  We pass a function which is called back with
 899    the following integer parameters:
 900
 901    FLOAT_P      nonzero if this represents a floating-point mode
 902    COMPLEX_P    nonzero is this represents a complex mode
 903    COUNT        count of number of items, nonzero for vector mode
 904    PRECISION    number of bits in data representation
 905    MANTISSA     number of bits in mantissa, if FP and known, else zero.
 906    SIZE         number of bits used to store data
 907    ALIGN        number of bits to which mode is aligned.  */
 908 extern void enumerate_modes (void (*f) (int, int, int, int, int, int,
 909                                         unsigned int));
 910
 911 /* Return the size of the FP mode with precision PREC.  */
 912 extern int fp_prec_to_size (int prec);
 913
 914 /* Return the precision of the FP mode with size SIZE.  */
 915 extern int fp_size_to_prec (int size);
 916
 917 /* These functions return the basic data type sizes and related parameters
 918    about the target machine.  */
 919
 920 extern Pos get_target_bits_per_unit (void);
 921 extern Pos get_target_bits_per_word (void);
 922 extern Pos get_target_char_size (void);
 923 extern Pos get_target_wchar_t_size (void);
 924 extern Pos get_target_short_size (void);
 925 extern Pos get_target_int_size (void);
 926 extern Pos get_target_long_size (void);
 927 extern Pos get_target_long_long_size (void);
 928 extern Pos get_target_float_size (void);
 929 extern Pos get_target_double_size (void);
 930 extern Pos get_target_long_double_size (void);
 931 extern Pos get_target_pointer_size (void);
 932 extern Pos get_target_maximum_default_alignment (void);
 933 extern Pos get_target_default_allocator_alignment (void);
 934 extern Pos get_target_maximum_allowed_alignment (void);
 935 extern Pos get_target_maximum_alignment (void);
 936 extern Nat get_float_words_be (void);
 937 extern Nat get_words_be (void);
 938 extern Nat get_bytes_be (void);
 939 extern Nat get_bits_be (void);
 940 extern Nat get_target_strict_alignment (void);
 941 extern Nat get_target_double_float_alignment (void);
 942 extern Nat get_target_double_scalar_alignment (void);
 943
 944 /* Let code know whether we are targetting VMS without need of
 945    intrusive preprocessor directives.  */
 946 #ifndef TARGET_ABI_OPEN_VMS
 947 #define TARGET_ABI_OPEN_VMS 0
 948 #endif
 949
 950 /* VMS macro set by default, when clear forces 32bit mallocs and 32bit
 951    Descriptors. Always used in combination with TARGET_ABI_OPEN_VMS
 952    so no effect on non-VMS systems.  */
 953 #ifndef TARGET_MALLOC64
 954 #define TARGET_MALLOC64 0
 955 #endif
 956
 957 /* Convenient shortcuts.  */
 958 #define VECTOR_TYPE_P(TYPE) (TREE_CODE (TYPE) == VECTOR_TYPE)