1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- T Y P E S -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2021, 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, go to -- 19-- http://www.gnu.org/licenses for a complete copy of the license. -- 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-- This package contains host independent type definitions which are used 27-- in more than one unit in the compiler. They are gathered here for easy 28-- reference, although in some cases the full description is found in the 29-- relevant module which implements the definition. The main reason that they 30-- are not in their "natural" specs is that this would cause a lot of inter- 31-- spec dependencies, and in particular some awkward circular dependencies 32-- would have to be dealt with. 33 34-- WARNING: There is a C version of this package. Any changes to this source 35-- file must be properly reflected in the C header file types.h 36 37-- Note: the declarations in this package reflect an expectation that the host 38-- machine has an efficient integer base type with a range at least 32 bits 39-- 2s-complement. If there are any machines for which this is not a correct 40-- assumption, a significant number of changes will be required. 41 42with System; 43with Unchecked_Conversion; 44with Unchecked_Deallocation; 45 46package Types is 47 pragma Preelaborate; 48 49 ------------------------------- 50 -- General Use Integer Types -- 51 ------------------------------- 52 53 type Int is range -2 ** 31 .. +2 ** 31 - 1; 54 -- Signed 32-bit integer 55 56 subtype Nat is Int range 0 .. Int'Last; 57 -- Non-negative Int values 58 59 subtype Pos is Int range 1 .. Int'Last; 60 -- Positive Int values 61 62 subtype Nonzero_Int is Int with Predicate => Nonzero_Int /= 0; 63 64 type Int_64 is range -2 ** 63 .. +2 ** 63 - 1; 65 -- Signed 64-bit integer 66 67 subtype Nat_64 is Int_64 range 0 .. Int_64'Last; 68 subtype Pos_64 is Int_64 range 1 .. Int_64'Last; 69 subtype Nonzero_Int_64 is Int_64 with Predicate => Nonzero_Int_64 /= 0; 70 71 type Word is mod 2 ** 32; 72 -- Unsigned 32-bit integer 73 74 type Short is range -32768 .. +32767; 75 for Short'Size use 16; 76 -- 16-bit signed integer 77 78 type Byte is mod 2 ** 8; 79 for Byte'Size use 8; 80 -- 8-bit unsigned integer 81 82 type size_t is mod 2 ** Standard'Address_Size; 83 -- Memory size value, for use in calls to C routines 84 85 -------------------------------------- 86 -- 8-Bit Character and String Types -- 87 -------------------------------------- 88 89 -- We use Standard.Character and Standard.String freely, since we are 90 -- compiling ourselves, and we properly implement the required 8-bit 91 -- character code as required in Ada 95. This section defines a few 92 -- general use constants and subtypes. 93 94 EOF : constant Character := ASCII.SUB; 95 -- The character SUB (16#1A#) is used in DOS and other systems derived 96 -- from DOS (XP, NT etc) to signal the end of a text file. Internally 97 -- all source files are ended by an EOF character, even on Unix systems. 98 -- An EOF character acts as the end of file only as the last character 99 -- of a source buffer, in any other position, it is treated as a blank 100 -- if it appears between tokens, and as an illegal character otherwise. 101 -- This makes life easier dealing with files that originated from DOS, 102 -- including concatenated files with interspersed EOF characters. 103 104 subtype Graphic_Character is Character range ' ' .. '~'; 105 -- Graphic characters, as defined in ARM 106 107 subtype Line_Terminator is Character range ASCII.LF .. ASCII.CR; 108 -- Line terminator characters (LF, VT, FF, CR). For further details, see 109 -- the extensive discussion of line termination in the Sinput spec. 110 111 subtype Upper_Half_Character is 112 Character range Character'Val (16#80#) .. Character'Val (16#FF#); 113 -- 8-bit Characters with the upper bit set 114 115 type Character_Ptr is access all Character; 116 type String_Ptr is access all String; 117 type String_Ptr_Const is access constant String; 118 -- Standard character and string pointers 119 120 procedure Free is new Unchecked_Deallocation (String, String_Ptr); 121 -- Procedure for freeing dynamically allocated String values 122 123 subtype Big_String is String (Positive); 124 type Big_String_Ptr is access all Big_String; 125 -- Virtual type for handling imported big strings. Note that we should 126 -- never have any allocators for this type, but we don't give a storage 127 -- size of zero, since there are legitimate deallocations going on. 128 129 function To_Big_String_Ptr is 130 new Unchecked_Conversion (System.Address, Big_String_Ptr); 131 -- Used to obtain Big_String_Ptr values from external addresses 132 133 subtype Word_Hex_String is String (1 .. 8); 134 -- Type used to represent Word value as 8 hex digits, with lower case 135 -- letters for the alphabetic cases. 136 137 function Get_Hex_String (W : Word) return Word_Hex_String; 138 -- Convert word value to 8-character hex string 139 140 ----------------------------------------- 141 -- Types Used for Text Buffer Handling -- 142 ----------------------------------------- 143 144 -- We cannot use type String for text buffers, since we must use the 145 -- standard 32-bit integer as an index value, since we count on all index 146 -- values being the same size. 147 148 type Text_Ptr is new Int; 149 -- Type used for subscripts in text buffer 150 151 type Text_Buffer is array (Text_Ptr range <>) of Character; 152 -- Text buffer used to hold source file or library information file 153 154 type Text_Buffer_Ptr is access all Text_Buffer; 155 -- Text buffers for input files are allocated dynamically and this type 156 -- is used to reference these text buffers. 157 158 procedure Free is new Unchecked_Deallocation (Text_Buffer, Text_Buffer_Ptr); 159 -- Procedure for freeing dynamically allocated text buffers 160 161 ------------------------------------------ 162 -- Types Used for Source Input Handling -- 163 ------------------------------------------ 164 165 type Logical_Line_Number is range 0 .. Int'Last; 166 for Logical_Line_Number'Size use 32; 167 -- Line number type, used for storing logical line numbers (i.e. line 168 -- numbers that include effects of any Source_Reference pragmas in the 169 -- source file). The value zero indicates a line containing a source 170 -- reference pragma. 171 172 No_Line_Number : constant Logical_Line_Number := 0; 173 -- Special value used to indicate no line number 174 175 type Physical_Line_Number is range 1 .. Int'Last; 176 for Physical_Line_Number'Size use 32; 177 -- Line number type, used for storing physical line numbers (i.e. line 178 -- numbers in the physical file being compiled, unaffected by the presence 179 -- of source reference pragmas). 180 181 type Column_Number is range 0 .. 32767; 182 for Column_Number'Size use 16; 183 -- Column number (assume that 2**15 - 1 is large enough). The range for 184 -- this type is used to compute Hostparm.Max_Line_Length. See also the 185 -- processing for -gnatyM in Stylesw). 186 187 No_Column_Number : constant Column_Number := 0; 188 -- Special value used to indicate no column number 189 190 Source_Align : constant := 2 ** 12; 191 -- Alignment requirement for source buffers (by keeping source buffers 192 -- aligned, we can optimize the implementation of Get_Source_File_Index. 193 -- See this routine in Sinput for details. 194 195 subtype Source_Buffer is Text_Buffer; 196 -- Type used to store text of a source file. The buffer for the main 197 -- source (the source specified on the command line) has a lower bound 198 -- starting at zero. Subsequent subsidiary sources have lower bounds 199 -- which are one greater than the previous upper bound, rounded up to 200 -- a multiple of Source_Align. 201 202 type Source_Buffer_Ptr_Var is access all Source_Buffer; 203 type Source_Buffer_Ptr is access constant Source_Buffer; 204 -- Pointer to source buffer. Source_Buffer_Ptr_Var is used for allocation 205 -- and deallocation; Source_Buffer_Ptr is used for all other uses of source 206 -- buffers. 207 208 function Null_Source_Buffer_Ptr (X : Source_Buffer_Ptr) return Boolean; 209 -- True if X = null 210 211 function Source_Buffer_Ptr_Equal (X, Y : Source_Buffer_Ptr) return Boolean 212 renames "="; 213 -- Squirrel away the predefined "=", for use in Null_Source_Buffer_Ptr. 214 -- Do not call this elsewhere. 215 216 function "=" (X, Y : Source_Buffer_Ptr) return Boolean is abstract; 217 -- Make "=" abstract. Note that this makes "/=" abstract as well. This is a 218 -- vestige of the zero-origin array indexing we used to use, where "=" is 219 -- always wrong (including the one in Null_Source_Buffer_Ptr). We keep this 220 -- just because we never need to compare Source_Buffer_Ptrs other than to 221 -- null. 222 223 subtype Source_Ptr is Text_Ptr; 224 -- Type used to represent a source location, which is a subscript of a 225 -- character in the source buffer. As noted above, different source buffers 226 -- have different ranges, so it is possible to tell from a Source_Ptr value 227 -- which source it refers to. Note that negative numbers are allowed to 228 -- accommodate the following special values. 229 230 type Source_Span is record 231 Ptr, First, Last : Source_Ptr; 232 end record; 233 -- Type used to represent a source span, consisting in a main location Ptr, 234 -- with a First and Last location, such that Ptr in First .. Last 235 236 function To_Span (Loc : Source_Ptr) return Source_Span is ((others => Loc)); 237 function To_Span (Ptr, First, Last : Source_Ptr) return Source_Span is 238 ((Ptr, First, Last)); 239 240 No_Location : constant Source_Ptr := -1; 241 -- Value used to indicate no source position set in a node. A test for a 242 -- Source_Ptr value being > No_Location is the approved way to test for a 243 -- standard value that does not include No_Location or any of the following 244 -- special definitions. One important use of No_Location is to label 245 -- generated nodes that we don't want the debugger to see in normal mode 246 -- (very often we conditionalize so that we set No_Location in normal mode 247 -- and the corresponding source line in -gnatD mode). 248 249 Standard_Location : constant Source_Ptr := -2; 250 -- Used for all nodes in the representation of package Standard other than 251 -- nodes representing the contents of Standard.ASCII. Note that testing for 252 -- a value being <= Standard_Location tests for both Standard_Location and 253 -- for Standard_ASCII_Location. 254 255 Standard_ASCII_Location : constant Source_Ptr := -3; 256 -- Used for all nodes in the presentation of package Standard.ASCII 257 258 System_Location : constant Source_Ptr := -4; 259 -- Used to identify locations of pragmas scanned by Targparm, where we know 260 -- the location is in System, but we don't know exactly what line. 261 262 First_Source_Ptr : constant Source_Ptr := 0; 263 -- Starting source pointer index value for first source program 264 265 ------------------------------------- 266 -- Range Definitions for Tree Data -- 267 ------------------------------------- 268 269 -- The tree has fields that can hold any of the following types: 270 271 -- Pointers to other tree nodes (type Node_Id) 272 -- List pointers (type List_Id) 273 -- Element list pointers (type Elist_Id) 274 -- Names (type Name_Id) 275 -- Strings (type String_Id) 276 -- Universal integers (type Uint) 277 -- Universal reals (type Ureal) 278 279 -- These types are represented as integer indices into various tables. 280 -- However, they should be treated as private, except in a few documented 281 -- cases. In particular it is usually inappropriate to perform arithmetic 282 -- operations using these types. One exception is in computing hash 283 -- functions of these types. 284 285 -- In most contexts, the strongly typed interface determines which of these 286 -- types is present. However, there are some situations (involving untyped 287 -- traversals of the tree), where it is convenient to be easily able to 288 -- distinguish these values. The underlying representation in all cases is 289 -- an integer type Union_Id, and we ensure that the range of the various 290 -- possible values for each of the above types is disjoint (except that 291 -- List_Id and Node_Id overlap at Empty) so that this distinction is 292 -- possible. 293 294 -- Note: it is also helpful for debugging purposes to make these ranges 295 -- distinct. If a bug leads to misidentification of a value, then it will 296 -- typically result in an out of range value and a Constraint_Error. 297 298 -- The range of Node_Id is most of the nonnegative integers. The other 299 -- ranges are negative. Uint has a very large range, because a substantial 300 -- part of this range is used to store direct values; see Uintp for 301 -- details. The other types have 100 million values, which should be 302 -- plenty. 303 304 type Union_Id is new Int; 305 -- The type in the tree for a union of possible ID values 306 307 -- Following are the Low and High bounds of the various ranges. 308 309 List_Low_Bound : constant := -099_999_999; 310 -- The List_Id values are subscripts into an array of list headers which 311 -- has List_Low_Bound as its lower bound. 312 313 List_High_Bound : constant := 0; 314 -- Maximum List_Id subscript value. The ranges of List_Id and Node_Id 315 -- overlap by one element (with value zero), which is used both for the 316 -- Empty node, and for No_List. The fact that the same value is used is 317 -- convenient because it means that the default value of Empty applies to 318 -- both nodes and lists, and also is more efficient to test for. 319 320 Node_Low_Bound : constant := 0; 321 -- The tree Id values start at zero, because we use zero for Empty (to 322 -- allow a zero test for Empty). 323 324 Node_High_Bound : constant := 1_999_999_999; 325 326 Elist_Low_Bound : constant := -199_999_999; 327 -- The Elist_Id values are subscripts into an array of elist headers which 328 -- has Elist_Low_Bound as its lower bound. 329 330 Elist_High_Bound : constant := -100_000_000; 331 332 Elmt_Low_Bound : constant := -299_999_999; 333 -- Low bound of element Id values. The use of these values is internal to 334 -- the Elists package, but the definition of the range is included here 335 -- since it must be disjoint from other Id values. The Elmt_Id values are 336 -- subscripts into an array of list elements which has this as lower bound. 337 338 Elmt_High_Bound : constant := -200_000_000; 339 340 Names_Low_Bound : constant := -399_999_999; 341 342 Names_High_Bound : constant := -300_000_000; 343 344 Strings_Low_Bound : constant := -499_999_999; 345 346 Strings_High_Bound : constant := -400_000_000; 347 348 Ureal_Low_Bound : constant := -599_999_999; 349 350 Ureal_High_Bound : constant := -500_000_000; 351 352 Uint_Low_Bound : constant := -2_100_000_000; 353 -- Low bound for Uint values 354 355 Uint_Table_Start : constant := -699_999_999; 356 -- Location where table entries for universal integers start (see 357 -- Uintp spec for details of the representation of Uint values). 358 359 Uint_High_Bound : constant := -600_000_000; 360 361 -- The following subtype definitions are used to provide convenient names 362 -- for membership tests on Int values to see what data type range they 363 -- lie in. Such tests appear only in the lowest level packages. 364 365 subtype List_Range is Union_Id 366 range List_Low_Bound .. List_High_Bound; 367 368 subtype Node_Range is Union_Id 369 range Node_Low_Bound .. Node_High_Bound; 370 371 subtype Elist_Range is Union_Id 372 range Elist_Low_Bound .. Elist_High_Bound; 373 374 subtype Elmt_Range is Union_Id 375 range Elmt_Low_Bound .. Elmt_High_Bound; 376 377 subtype Names_Range is Union_Id 378 range Names_Low_Bound .. Names_High_Bound; 379 380 subtype Strings_Range is Union_Id 381 range Strings_Low_Bound .. Strings_High_Bound; 382 383 subtype Uint_Range is Union_Id 384 range Uint_Low_Bound .. Uint_High_Bound; 385 386 subtype Ureal_Range is Union_Id 387 range Ureal_Low_Bound .. Ureal_High_Bound; 388 389 ----------------------------- 390 -- Types for Atree Package -- 391 ----------------------------- 392 393 -- Node_Id values are used to identify nodes in the tree. They are 394 -- subscripts into the Nodes table declared in package Atree. Note that 395 -- the special values Empty and Error are subscripts into this table. 396 -- See package Atree for further details. 397 398 type Node_Id is range Node_Low_Bound .. Node_High_Bound with Size => 32; 399 -- Type used to identify nodes in the tree 400 401 subtype Entity_Id is Node_Id; 402 -- A synonym for node types, used in the Einfo package to refer to nodes 403 -- that are entities (i.e. nodes with an Nkind of N_Defining_xxx). All such 404 -- nodes are extended nodes and these are the only extended nodes, so that 405 -- in practice entity and extended nodes are synonymous. 406 407 subtype Node_Or_Entity_Id is Node_Id; 408 -- A synonym for node types, used in cases where a given value may be used 409 -- to represent either a node or an entity. We like to minimize such uses 410 -- for obvious reasons of logical type consistency, but where such uses 411 -- occur, they should be documented by use of this type. 412 413 Empty : constant Node_Id := Node_Low_Bound; 414 -- Used to indicate null node. A node is actually allocated with this 415 -- Id value, so that Nkind (Empty) = N_Empty. Note that Node_Low_Bound 416 -- is zero, so Empty = No_List = zero. 417 418 Empty_List_Or_Node : constant := 0; 419 -- This constant is used in situations (e.g. initializing empty fields) 420 -- where the value set will be used to represent either an empty node or 421 -- a non-existent list, depending on the context. 422 423 Error : constant Node_Id := Node_Low_Bound + 1; 424 -- Used to indicate an error in the source program. A node is actually 425 -- allocated with this Id value, so that Nkind (Error) = N_Error. 426 427 Empty_Or_Error : constant Node_Id := Error; 428 -- Since Empty and Error are the first two Node_Id values, the test for 429 -- N <= Empty_Or_Error tests to see if N is Empty or Error. This definition 430 -- provides convenient self-documentation for such tests. 431 432 First_Node_Id : constant Node_Id := Node_Low_Bound; 433 -- Subscript of first allocated node. Note that Empty and Error are both 434 -- allocated nodes, whose Nkind fields can be accessed without error. 435 436 ------------------------------ 437 -- Types for Nlists Package -- 438 ------------------------------ 439 440 -- List_Id values are used to identify node lists stored in the tree, so 441 -- that each node can be on at most one such list (see package Nlists for 442 -- further details). Note that the special value Error_List is a subscript 443 -- in this table, but the value No_List is *not* a valid subscript, and any 444 -- attempt to apply list operations to No_List will cause a (detected) 445 -- error. 446 447 type List_Id is range List_Low_Bound .. List_High_Bound with Size => 32; 448 -- Type used to identify a node list 449 450 No_List : constant List_Id := List_High_Bound; 451 -- Used to indicate absence of a list. Note that the value is zero, which 452 -- is the same as Empty, which is helpful in initializing nodes where a 453 -- value of zero can represent either an empty node or an empty list. 454 455 Error_List : constant List_Id := List_Low_Bound; 456 -- Used to indicate that there was an error in the source program in a 457 -- context which would normally require a list. This node appears to be 458 -- an empty list to the list operations (a null list is actually allocated 459 -- which has this Id value). 460 461 First_List_Id : constant List_Id := Error_List; 462 -- Subscript of first allocated list header 463 464 ------------------------------ 465 -- Types for Elists Package -- 466 ------------------------------ 467 468 -- Element list Id values are used to identify element lists stored outside 469 -- of the tree, allowing nodes to be members of more than one such list 470 -- (see package Elists for further details). 471 472 type Elist_Id is range Elist_Low_Bound .. Elist_High_Bound with Size => 32; 473 -- Type used to identify an element list (Elist header table subscript) 474 475 No_Elist : constant Elist_Id := Elist_Low_Bound; 476 -- Used to indicate absence of an element list. Note that this is not an 477 -- actual Elist header, so element list operations on this value are not 478 -- valid. 479 480 First_Elist_Id : constant Elist_Id := No_Elist + 1; 481 -- Subscript of first allocated Elist header 482 483 -- Element Id values are used to identify individual elements of an element 484 -- list (see package Elists for further details). 485 486 type Elmt_Id is range Elmt_Low_Bound .. Elmt_High_Bound; 487 -- Type used to identify an element list 488 489 No_Elmt : constant Elmt_Id := Elmt_Low_Bound; 490 -- Used to represent empty element 491 492 First_Elmt_Id : constant Elmt_Id := No_Elmt + 1; 493 -- Subscript of first allocated Elmt table entry 494 495 ------------------------------- 496 -- Types for Stringt Package -- 497 ------------------------------- 498 499 -- String_Id values are used to identify entries in the strings table. They 500 -- are subscripts into the Strings table defined in package Stringt. 501 502 type String_Id is range Strings_Low_Bound .. Strings_High_Bound 503 with Size => 32; 504 -- Type used to identify entries in the strings table 505 506 No_String : constant String_Id := Strings_Low_Bound; 507 -- Used to indicate missing string Id. Note that the value zero is used 508 -- to indicate a missing data value for all the Int types in this section. 509 510 First_String_Id : constant String_Id := No_String + 1; 511 -- First subscript allocated in string table 512 513 ------------------------- 514 -- Character Code Type -- 515 ------------------------- 516 517 -- The type Char is used for character data internally in the compiler, but 518 -- character codes in the source are represented by the Char_Code type. 519 -- Each character literal in the source is interpreted as being one of the 520 -- 16#7FFF_FFFF# possible Wide_Wide_Character codes, and a unique Integer 521 -- value is assigned, corresponding to the UTF-32 value, which also 522 -- corresponds to the Pos value in the Wide_Wide_Character type, and also 523 -- corresponds to the Pos value in the Wide_Character and Character types 524 -- for values that are in appropriate range. String literals are similarly 525 -- interpreted as a sequence of such codes. 526 527 type Char_Code_Base is mod 2 ** 32; 528 for Char_Code_Base'Size use 32; 529 530 subtype Char_Code is Char_Code_Base range 0 .. 16#7FFF_FFFF#; 531 for Char_Code'Value_Size use 32; 532 for Char_Code'Object_Size use 32; 533 534 function Get_Char_Code (C : Character) return Char_Code; 535 pragma Inline (Get_Char_Code); 536 -- Function to obtain internal character code from source character. For 537 -- the moment, the internal character code is simply the Pos value of the 538 -- input source character, but we provide this interface for possible 539 -- later support of alternative character sets. 540 541 function In_Character_Range (C : Char_Code) return Boolean; 542 pragma Inline (In_Character_Range); 543 -- Determines if the given character code is in range of type Character, 544 -- and if so, returns True. If not, returns False. 545 546 function In_Wide_Character_Range (C : Char_Code) return Boolean; 547 pragma Inline (In_Wide_Character_Range); 548 -- Determines if the given character code is in range of the type 549 -- Wide_Character, and if so, returns True. If not, returns False. 550 551 function Get_Character (C : Char_Code) return Character; 552 pragma Inline (Get_Character); 553 -- For a character C that is in Character range (see above function), this 554 -- function returns the corresponding Character value. It is an error to 555 -- call Get_Character if C is not in Character range. 556 557 function Get_Wide_Character (C : Char_Code) return Wide_Character; 558 -- For a character C that is in Wide_Character range (see above function), 559 -- this function returns the corresponding Wide_Character value. It is an 560 -- error to call Get_Wide_Character if C is not in Wide_Character range. 561 562 --------------------------------------- 563 -- Types used for Library Management -- 564 --------------------------------------- 565 566 type Unit_Number_Type is new Int range -1 .. Int'Last; 567 -- Unit number. The main source is unit 0, and subsidiary sources have 568 -- non-zero numbers starting with 1. Unit numbers are used to index the 569 -- Units table in package Lib. 570 571 Main_Unit : constant Unit_Number_Type := 0; 572 -- Unit number value for main unit 573 574 No_Unit : constant Unit_Number_Type := -1; 575 -- Special value used to signal no unit 576 577 type Source_File_Index is new Int range -1 .. Int'Last; 578 -- Type used to index the source file table (see package Sinput) 579 580 No_Source_File : constant Source_File_Index := 0; 581 -- Value used to indicate no source file present 582 583 No_Access_To_Source_File : constant Source_File_Index := -1; 584 -- Value used to indicate a source file is present but unreadable 585 586 ----------------------------------- 587 -- Representation of Time Stamps -- 588 ----------------------------------- 589 590 -- All compiled units are marked with a time stamp which is derived from 591 -- the source file (we assume that the host system has the concept of a 592 -- file time stamp which is modified when a file is modified). These 593 -- time stamps are used to ensure consistency of the set of units that 594 -- constitutes a library. Time stamps are 14-character strings with 595 -- with the following format: 596 597 -- YYYYMMDDHHMMSS 598 599 -- YYYY year 600 -- MM month (2 digits 01-12) 601 -- DD day (2 digits 01-31) 602 -- HH hour (2 digits 00-23) 603 -- MM minutes (2 digits 00-59) 604 -- SS seconds (2 digits 00-59) 605 606 -- In the case of Unix systems (and other systems which keep the time in 607 -- GMT), the time stamp is the GMT time of the file, not the local time. 608 -- This solves problems in using libraries across networks with clients 609 -- spread across multiple time-zones. 610 611 Time_Stamp_Length : constant := 14; 612 -- Length of time stamp value 613 614 subtype Time_Stamp_Index is Natural range 1 .. Time_Stamp_Length; 615 type Time_Stamp_Type is new String (Time_Stamp_Index); 616 -- Type used to represent time stamp 617 618 Empty_Time_Stamp : constant Time_Stamp_Type := (others => ' '); 619 -- Value representing an empty or missing time stamp. Looks less than any 620 -- real time stamp if two time stamps are compared. Note that although this 621 -- is not private, clients should not rely on the exact way in which this 622 -- string is represented, and instead should use the subprograms below. 623 624 Dummy_Time_Stamp : constant Time_Stamp_Type := (others => '0'); 625 -- This is used for dummy time stamp values used in the D lines for 626 -- non-existent files, and is intended to be an impossible value. 627 628 function "=" (Left, Right : Time_Stamp_Type) return Boolean; 629 function "<=" (Left, Right : Time_Stamp_Type) return Boolean; 630 function ">=" (Left, Right : Time_Stamp_Type) return Boolean; 631 function "<" (Left, Right : Time_Stamp_Type) return Boolean; 632 function ">" (Left, Right : Time_Stamp_Type) return Boolean; 633 -- Comparison functions on time stamps. Note that two time stamps are 634 -- defined as being equal if they have the same day/month/year and the 635 -- hour/minutes/seconds values are within 2 seconds of one another. This 636 -- deals with rounding effects in library file time stamps caused by 637 -- copying operations during installation. We have particularly noticed 638 -- that WinNT seems susceptible to such changes. 639 -- 640 -- Note: the Empty_Time_Stamp value looks equal to itself, and less than 641 -- any non-empty time stamp value. 642 643 procedure Split_Time_Stamp 644 (TS : Time_Stamp_Type; 645 Year : out Nat; 646 Month : out Nat; 647 Day : out Nat; 648 Hour : out Nat; 649 Minutes : out Nat; 650 Seconds : out Nat); 651 -- Given a time stamp, decompose it into its components 652 653 procedure Make_Time_Stamp 654 (Year : Nat; 655 Month : Nat; 656 Day : Nat; 657 Hour : Nat; 658 Minutes : Nat; 659 Seconds : Nat; 660 TS : out Time_Stamp_Type); 661 -- Given the components of a time stamp, initialize the value 662 663 ------------------------------------- 664 -- Types used for Check Management -- 665 ------------------------------------- 666 667 type Check_Id is new Nat; 668 -- Type used to represent a check id 669 670 No_Check_Id : constant := 0; 671 -- Check_Id value used to indicate no check 672 673 Access_Check : constant := 1; 674 Accessibility_Check : constant := 2; 675 Alignment_Check : constant := 3; 676 Allocation_Check : constant := 4; 677 Atomic_Synchronization : constant := 5; 678 Characters_Assertion_Check : constant := 6; 679 Containers_Assertion_Check : constant := 7; 680 Discriminant_Check : constant := 8; 681 Division_Check : constant := 9; 682 Duplicated_Tag_Check : constant := 10; 683 Elaboration_Check : constant := 11; 684 Index_Check : constant := 12; 685 Interfaces_Assertion_Check : constant := 13; 686 IO_Assertion_Check : constant := 14; 687 Length_Check : constant := 15; 688 Numerics_Assertion_Check : constant := 16; 689 Overflow_Check : constant := 17; 690 Predicate_Check : constant := 18; 691 Program_Error_Check : constant := 19; 692 Range_Check : constant := 20; 693 Storage_Check : constant := 21; 694 Strings_Assertion_Check : constant := 22; 695 System_Assertion_Check : constant := 23; 696 Tag_Check : constant := 24; 697 Validity_Check : constant := 25; 698 Container_Checks : constant := 26; 699 Tampering_Check : constant := 27; 700 Tasking_Check : constant := 28; 701 -- Values used to represent individual predefined checks (including the 702 -- setting of Atomic_Synchronization, which is implemented internally using 703 -- a "check" whose name is Atomic_Synchronization). 704 705 All_Checks : constant := 29; 706 -- Value used to represent All_Checks value 707 708 subtype Predefined_Check_Id is Check_Id range 1 .. All_Checks; 709 -- Subtype for predefined checks, including All_Checks 710 711 -- The following array contains an entry for each recognized check name 712 -- for pragma Suppress. It is used to represent current settings of scope 713 -- based suppress actions from pragma Suppress or command line settings. 714 715 -- Note: when Suppress_Array (All_Checks) is True, then generally all other 716 -- specific check entries are set True, except for the Elaboration_Check 717 -- entry which is set only if an explicit Suppress for this check is given. 718 -- The reason for this non-uniformity is that we do not want All_Checks to 719 -- suppress elaboration checking when using the static elaboration model. 720 -- We recognize only an explicit suppress of Elaboration_Check as a signal 721 -- that the static elaboration checking should skip a compile time check. 722 723 type Suppress_Array is array (Predefined_Check_Id) of Boolean; 724 pragma Pack (Suppress_Array); 725 726 -- To add a new check type to GNAT, the following steps are required: 727 728 -- 1. Add an entry to Snames spec for the new name 729 -- 2. Add an entry to the definition of Check_Id above (very important: 730 -- these definitions should be in the same order in Snames and here) 731 -- 3. Add a new function to Checks to handle the new check test 732 -- 4. Add a new Do_xxx_Check flag to Sinfo (if required) 733 -- 5. Add appropriate checks for the new test 734 735 -- The following provides precise details on the mode used to generate 736 -- code for intermediate operations in expressions for signed integer 737 -- arithmetic (and how to generate overflow checks if enabled). Note 738 -- that this only affects handling of intermediate results. The final 739 -- result must always fit within the target range, and if overflow 740 -- checking is enabled, the check on the final result is against this 741 -- target range. 742 743 type Overflow_Mode_Type is ( 744 Not_Set, 745 -- Dummy value used during initialization process to show that the 746 -- corresponding value has not yet been initialized. 747 748 Strict, 749 -- Operations are done in the base type of the subexpression. If 750 -- overflow checks are enabled, then the check is against the range 751 -- of this base type. 752 753 Minimized, 754 -- Where appropriate, intermediate arithmetic operations are performed 755 -- with an extended range, using Long_Long_Integer if necessary. If 756 -- overflow checking is enabled, then the check is against the range 757 -- of Long_Long_Integer. 758 759 Eliminated); 760 -- In this mode arbitrary precision arithmetic is used as needed to 761 -- ensure that it is impossible for intermediate arithmetic to cause an 762 -- overflow. In this mode, intermediate expressions are not affected by 763 -- the overflow checking mode, since overflows are eliminated. 764 765 subtype Minimized_Or_Eliminated is 766 Overflow_Mode_Type range Minimized .. Eliminated; 767 -- Define subtype so that clients don't need to know ordering. Note that 768 -- Overflow_Mode_Type is not marked as an ordered enumeration type. 769 770 -- The following structure captures the state of check suppression or 771 -- activation at a particular point in the program execution. 772 773 type Suppress_Record is record 774 Suppress : Suppress_Array; 775 -- Indicates suppression status of each possible check 776 777 Overflow_Mode_General : Overflow_Mode_Type; 778 -- This field indicates the mode for handling code generation and 779 -- overflow checking (if enabled) for intermediate expression values. 780 -- This applies to general expressions outside assertions. 781 782 Overflow_Mode_Assertions : Overflow_Mode_Type; 783 -- This field indicates the mode for handling code generation and 784 -- overflow checking (if enabled) for intermediate expression values. 785 -- This applies to any expression occurring inside assertions. 786 end record; 787 788 ----------------------------------- 789 -- Global Exception Declarations -- 790 ----------------------------------- 791 792 -- This section contains declarations of exceptions that are used 793 -- throughout the compiler or in other GNAT tools. 794 795 Unrecoverable_Error : exception; 796 -- This exception is raised to immediately terminate the compilation of the 797 -- current source program. Used in situations where things are bad enough 798 -- that it doesn't seem worth continuing (e.g. max errors reached, or a 799 -- required file is not found). Also raised when the compiler finds itself 800 -- in trouble after an error (see Comperr). 801 802 Terminate_Program : exception; 803 -- This exception is raised to immediately terminate the tool being 804 -- executed. Each tool where this exception may be raised must have a 805 -- single exception handler that contains only a null statement and that is 806 -- the last statement of the program. If needed, procedure Set_Exit_Status 807 -- is called with the appropriate exit status before raising 808 -- Terminate_Program. 809 810 --------------------------------- 811 -- Parameter Mechanism Control -- 812 --------------------------------- 813 814 -- Function and parameter entities have a field that records the passing 815 -- mechanism. See specification of Sem_Mech for full details. The following 816 -- subtype is used to represent values of this type: 817 818 subtype Mechanism_Type is Int range -2 .. Int'Last; 819 -- Type used to represent a mechanism value. This is a subtype rather than 820 -- a type to avoid some annoying processing problems with certain routines 821 -- in Einfo (processing them to create the corresponding C). The values in 822 -- the range -2 .. 0 are used to represent mechanism types declared as 823 -- named constants in the spec of Sem_Mech. Positive values are used for 824 -- the case of a pragma C_Pass_By_Copy that sets a threshold value for the 825 -- mechanism to be used. For example if pragma C_Pass_By_Copy (32) is given 826 -- then Default_C_Record_Mechanism is set to 32, and the meaning is to use 827 -- By_Reference if the size is greater than 32, and By_Copy otherwise. 828 829 --------------------------------- 830 -- Component_Alignment Control -- 831 --------------------------------- 832 833 -- There are four types of alignment possible for array and record 834 -- types, and a field in the type entities contains a value of the 835 -- following type indicating which alignment choice applies. For full 836 -- details of the meaning of these alignment types, see description 837 -- of the Component_Alignment pragma. 838 839 type Component_Alignment_Kind is ( 840 Calign_Default, -- default alignment 841 Calign_Component_Size, -- natural alignment for component size 842 Calign_Component_Size_4, -- natural for size <= 4, 4 for size >= 4 843 Calign_Storage_Unit); -- all components byte aligned 844 845 ----------------------------------- 846 -- Floating Point Representation -- 847 ----------------------------------- 848 849 type Float_Rep_Kind is (IEEE_Binary); 850 -- The only one supported now is IEEE 754p conforming binary format, but 851 -- other formats were supported in the past, and could conceivably be 852 -- supported in the future, so we keep this singleton enumeration type. 853 854 ---------------------------- 855 -- Small_Paren_Count_Type -- 856 ---------------------------- 857 858 -- See Paren_Count in Atree for documentation 859 860 subtype Small_Paren_Count_Type is Nat range 0 .. 3; 861 862 ------------------------------ 863 -- Run-Time Exception Codes -- 864 ------------------------------ 865 866 -- When the code generator generates a run-time exception, it provides a 867 -- reason code which is one of the following. This reason code is used to 868 -- select the appropriate run-time routine to be called, determining both 869 -- the exception to be raised, and the message text to be added. 870 871 -- The prefix CE/PE/SE indicates the exception to be raised 872 -- CE = Constraint_Error 873 -- PE = Program_Error 874 -- SE = Storage_Error 875 876 -- The remaining part of the name indicates the message text to be added, 877 -- where all letters are lower case, and underscores are converted to 878 -- spaces (for example CE_Invalid_Data adds the text "invalid data"). 879 880 -- To add a new code, you need to do the following: 881 882 -- 1. Assign a new number to the reason. Do not renumber existing codes, 883 -- since this causes compatibility/bootstrap issues, so always add the 884 -- new code at the end of the list. 885 886 -- 2. Update the contents of the array Kind 887 888 -- 3. Modify the corresponding definitions in types.h, including the 889 -- definition of last_reason_code. 890 891 -- 4. Add the name of the routines in exp_ch11.Get_RT_Exception_Name 892 893 -- 5. Add a new routine in Ada.Exceptions with the appropriate call and 894 -- static string constant. Note that there is more than one version 895 -- of a-except.adb which must be modified. 896 897 -- Note on ordering of references. For the tables in Ada.Exceptions units, 898 -- usually the ordering does not matter, and we use the same ordering as 899 -- is used here. 900 901 type RT_Exception_Code is 902 (CE_Access_Check_Failed, -- 00 903 CE_Access_Parameter_Is_Null, -- 01 904 CE_Discriminant_Check_Failed, -- 02 905 CE_Divide_By_Zero, -- 03 906 CE_Explicit_Raise, -- 04 907 CE_Index_Check_Failed, -- 05 908 CE_Invalid_Data, -- 06 909 CE_Length_Check_Failed, -- 07 910 CE_Null_Exception_Id, -- 08 911 CE_Null_Not_Allowed, -- 09 912 913 CE_Overflow_Check_Failed, -- 10 914 CE_Partition_Check_Failed, -- 11 915 CE_Range_Check_Failed, -- 12 916 CE_Tag_Check_Failed, -- 13 917 PE_Access_Before_Elaboration, -- 14 918 PE_Accessibility_Check_Failed, -- 15 919 PE_Address_Of_Intrinsic, -- 16 920 PE_Aliased_Parameters, -- 17 921 PE_All_Guards_Closed, -- 18 922 PE_Bad_Predicated_Generic_Type, -- 19 923 924 PE_Current_Task_In_Entry_Body, -- 20 925 PE_Duplicated_Entry_Address, -- 21 926 PE_Explicit_Raise, -- 22 927 PE_Finalize_Raised_Exception, -- 23 928 PE_Implicit_Return, -- 24 929 PE_Misaligned_Address_Value, -- 25 930 PE_Missing_Return, -- 26 931 PE_Overlaid_Controlled_Object, -- 27 932 PE_Potentially_Blocking_Operation, -- 28 933 PE_Stubbed_Subprogram_Called, -- 29 934 935 PE_Unchecked_Union_Restriction, -- 30 936 PE_Non_Transportable_Actual, -- 31 937 SE_Empty_Storage_Pool, -- 32 938 SE_Explicit_Raise, -- 33 939 SE_Infinite_Recursion, -- 34 940 SE_Object_Too_Large, -- 35 941 PE_Stream_Operation_Not_Allowed, -- 36 942 PE_Build_In_Place_Mismatch); -- 37 943 pragma Convention (C, RT_Exception_Code); 944 945 Last_Reason_Code : constant := 946 RT_Exception_Code'Pos (RT_Exception_Code'Last); 947 -- Last reason code 948 949 type Reason_Kind is (CE_Reason, PE_Reason, SE_Reason); 950 -- Categorization of reason codes by exception raised 951 952 Rkind : constant array (RT_Exception_Code range <>) of Reason_Kind := 953 (CE_Access_Check_Failed => CE_Reason, 954 CE_Access_Parameter_Is_Null => CE_Reason, 955 CE_Discriminant_Check_Failed => CE_Reason, 956 CE_Divide_By_Zero => CE_Reason, 957 CE_Explicit_Raise => CE_Reason, 958 CE_Index_Check_Failed => CE_Reason, 959 CE_Invalid_Data => CE_Reason, 960 CE_Length_Check_Failed => CE_Reason, 961 CE_Null_Exception_Id => CE_Reason, 962 CE_Null_Not_Allowed => CE_Reason, 963 CE_Overflow_Check_Failed => CE_Reason, 964 CE_Partition_Check_Failed => CE_Reason, 965 CE_Range_Check_Failed => CE_Reason, 966 CE_Tag_Check_Failed => CE_Reason, 967 968 PE_Access_Before_Elaboration => PE_Reason, 969 PE_Accessibility_Check_Failed => PE_Reason, 970 PE_Address_Of_Intrinsic => PE_Reason, 971 PE_Aliased_Parameters => PE_Reason, 972 PE_All_Guards_Closed => PE_Reason, 973 PE_Bad_Predicated_Generic_Type => PE_Reason, 974 PE_Current_Task_In_Entry_Body => PE_Reason, 975 PE_Duplicated_Entry_Address => PE_Reason, 976 PE_Explicit_Raise => PE_Reason, 977 PE_Finalize_Raised_Exception => PE_Reason, 978 PE_Implicit_Return => PE_Reason, 979 PE_Misaligned_Address_Value => PE_Reason, 980 PE_Missing_Return => PE_Reason, 981 PE_Overlaid_Controlled_Object => PE_Reason, 982 PE_Potentially_Blocking_Operation => PE_Reason, 983 PE_Stubbed_Subprogram_Called => PE_Reason, 984 PE_Unchecked_Union_Restriction => PE_Reason, 985 PE_Non_Transportable_Actual => PE_Reason, 986 PE_Stream_Operation_Not_Allowed => PE_Reason, 987 PE_Build_In_Place_Mismatch => PE_Reason, 988 989 SE_Empty_Storage_Pool => SE_Reason, 990 SE_Explicit_Raise => SE_Reason, 991 SE_Infinite_Recursion => SE_Reason, 992 SE_Object_Too_Large => SE_Reason); 993 994 -- Types for field offsets/sizes used in Seinfo, Sinfo.Nodes and 995 -- Einfo.Entities: 996 997 type Field_Offset is new Nat; 998 -- Offset of a node field, in units of the size of the field, which is 999 -- always a power of 2. 1000 1001 subtype Node_Offset is Field_Offset'Base range 1 .. Field_Offset'Base'Last; 1002 1003 subtype Slot_Count is Field_Offset; 1004 -- Count of number of slots. Same type as Field_Offset to avoid 1005 -- proliferation of type conversions. 1006 1007 subtype Field_Size_In_Bits is Field_Offset with Predicate => 1008 Field_Size_In_Bits in 1 | 2 | 4 | 8 | 32; 1009 1010 subtype Opt_Field_Offset is Field_Offset'Base range -1 .. Field_Offset'Last; 1011 No_Field_Offset : constant Opt_Field_Offset := Opt_Field_Offset'First; 1012 1013 type Offset_Array_Index is new Nat; 1014 type Offset_Array is 1015 array (Offset_Array_Index range <>) of Opt_Field_Offset; 1016 1017end Types; 1018