1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- T Y P E S -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2015, 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. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32-- This package contains host independent type definitions which are used 33-- in more than one unit in the compiler. They are gathered here for easy 34-- reference, although in some cases the full description is found in the 35-- relevant module which implements the definition. The main reason that they 36-- are not in their "natural" specs is that this would cause a lot of inter- 37-- spec dependencies, and in particular some awkward circular dependencies 38-- would have to be dealt with. 39 40-- WARNING: There is a C version of this package. Any changes to this source 41-- file must be properly reflected in the C header file types.h declarations. 42 43-- Note: the declarations in this package reflect an expectation that the host 44-- machine has an efficient integer base type with a range at least 32 bits 45-- 2s-complement. If there are any machines for which this is not a correct 46-- assumption, a significant number of changes will be required. 47 48with System; 49with Unchecked_Conversion; 50with Unchecked_Deallocation; 51 52package Types is 53 pragma Preelaborate; 54 55 ------------------------------- 56 -- General Use Integer Types -- 57 ------------------------------- 58 59 type Int is range -2 ** 31 .. +2 ** 31 - 1; 60 -- Signed 32-bit integer 61 62 subtype Nat is Int range 0 .. Int'Last; 63 -- Non-negative Int values 64 65 subtype Pos is Int range 1 .. Int'Last; 66 -- Positive Int values 67 68 type Word is mod 2 ** 32; 69 -- Unsigned 32-bit integer 70 71 type Short is range -32768 .. +32767; 72 for Short'Size use 16; 73 -- 16-bit signed integer 74 75 type Byte is mod 2 ** 8; 76 for Byte'Size use 8; 77 -- 8-bit unsigned integer 78 79 type size_t is mod 2 ** Standard'Address_Size; 80 -- Memory size value, for use in calls to C routines 81 82 -------------------------------------- 83 -- 8-Bit Character and String Types -- 84 -------------------------------------- 85 86 -- We use Standard.Character and Standard.String freely, since we are 87 -- compiling ourselves, and we properly implement the required 8-bit 88 -- character code as required in Ada 95. This section defines a few 89 -- general use constants and subtypes. 90 91 EOF : constant Character := ASCII.SUB; 92 -- The character SUB (16#1A#) is used in DOS and other systems derived 93 -- from DOS (XP, NT etc) to signal the end of a text file. Internally 94 -- all source files are ended by an EOF character, even on Unix systems. 95 -- An EOF character acts as the end of file only as the last character 96 -- of a source buffer, in any other position, it is treated as a blank 97 -- if it appears between tokens, and as an illegal character otherwise. 98 -- This makes life easier dealing with files that originated from DOS, 99 -- including concatenated files with interspersed EOF characters. 100 101 subtype Graphic_Character is Character range ' ' .. '~'; 102 -- Graphic characters, as defined in ARM 103 104 subtype Line_Terminator is Character range ASCII.LF .. ASCII.CR; 105 -- Line terminator characters (LF, VT, FF, CR). For further details, see 106 -- the extensive discussion of line termination in the Sinput spec. 107 108 subtype Upper_Half_Character is 109 Character range Character'Val (16#80#) .. Character'Val (16#FF#); 110 -- 8-bit Characters with the upper bit set 111 112 type Character_Ptr is access all Character; 113 type String_Ptr is access all String; 114 type String_Ptr_Const is access constant String; 115 -- Standard character and string pointers 116 117 procedure Free is new Unchecked_Deallocation (String, String_Ptr); 118 -- Procedure for freeing dynamically allocated String values 119 120 subtype Big_String is String (Positive); 121 type Big_String_Ptr is access all Big_String; 122 -- Virtual type for handling imported big strings. Note that we should 123 -- never have any allocators for this type, but we don't give a storage 124 -- size of zero, since there are legitimate deallocations going on. 125 126 function To_Big_String_Ptr is 127 new Unchecked_Conversion (System.Address, Big_String_Ptr); 128 -- Used to obtain Big_String_Ptr values from external addresses 129 130 subtype Word_Hex_String is String (1 .. 8); 131 -- Type used to represent Word value as 8 hex digits, with lower case 132 -- letters for the alphabetic cases. 133 134 function Get_Hex_String (W : Word) return Word_Hex_String; 135 -- Convert word value to 8-character hex string 136 137 ----------------------------------------- 138 -- Types Used for Text Buffer Handling -- 139 ----------------------------------------- 140 141 -- We can not use type String for text buffers, since we must use the 142 -- standard 32-bit integer as an index value, since we count on all index 143 -- values being the same size. 144 145 type Text_Ptr is new Int; 146 -- Type used for subscripts in text buffer 147 148 type Text_Buffer is array (Text_Ptr range <>) of Character; 149 -- Text buffer used to hold source file or library information file 150 151 type Text_Buffer_Ptr is access all Text_Buffer; 152 -- Text buffers for input files are allocated dynamically and this type 153 -- is used to reference these text buffers. 154 155 procedure Free is new Unchecked_Deallocation (Text_Buffer, Text_Buffer_Ptr); 156 -- Procedure for freeing dynamically allocated text buffers 157 158 ------------------------------------------ 159 -- Types Used for Source Input Handling -- 160 ------------------------------------------ 161 162 type Logical_Line_Number is range 0 .. Int'Last; 163 for Logical_Line_Number'Size use 32; 164 -- Line number type, used for storing logical line numbers (i.e. line 165 -- numbers that include effects of any Source_Reference pragmas in the 166 -- source file). The value zero indicates a line containing a source 167 -- reference pragma. 168 169 No_Line_Number : constant Logical_Line_Number := 0; 170 -- Special value used to indicate no line number 171 172 type Physical_Line_Number is range 1 .. Int'Last; 173 for Physical_Line_Number'Size use 32; 174 -- Line number type, used for storing physical line numbers (i.e. line 175 -- numbers in the physical file being compiled, unaffected by the presence 176 -- of source reference pragmas). 177 178 type Column_Number is range 0 .. 32767; 179 for Column_Number'Size use 16; 180 -- Column number (assume that 2**15 - 1 is large enough). The range for 181 -- this type is used to compute Hostparm.Max_Line_Length. See also the 182 -- processing for -gnatyM in Stylesw). 183 184 No_Column_Number : constant Column_Number := 0; 185 -- Special value used to indicate no column number 186 187 Source_Align : constant := 2 ** 12; 188 -- Alignment requirement for source buffers (by keeping source buffers 189 -- aligned, we can optimize the implementation of Get_Source_File_Index. 190 -- See this routine in Sinput for details. 191 192 subtype Source_Buffer is Text_Buffer; 193 -- Type used to store text of a source file. The buffer for the main 194 -- source (the source specified on the command line) has a lower bound 195 -- starting at zero. Subsequent subsidiary sources have lower bounds 196 -- which are one greater than the previous upper bound, rounded up to 197 -- a multiple of Source_Align. 198 199 subtype Big_Source_Buffer is Text_Buffer (0 .. Text_Ptr'Last); 200 -- This is a virtual type used as the designated type of the access type 201 -- Source_Buffer_Ptr, see Osint.Read_Source_File for details. 202 203 type Source_Buffer_Ptr is access all Big_Source_Buffer; 204 -- Pointer to source buffer. We use virtual origin addressing for source 205 -- buffers, with thin pointers. The pointer points to a virtual instance 206 -- of type Big_Source_Buffer, where the actual type is in fact of type 207 -- Source_Buffer. The address is adjusted so that the virtual origin 208 -- addressing works correctly. See Osint.Read_Source_Buffer for further 209 -- details. Again, as for Big_String_Ptr, we should never allocate using 210 -- this type, but we don't give a storage size clause of zero, since we 211 -- may end up doing deallocations of instances allocated manually. 212 213 subtype Source_Ptr is Text_Ptr; 214 -- Type used to represent a source location, which is a subscript of a 215 -- character in the source buffer. As noted above, different source buffers 216 -- have different ranges, so it is possible to tell from a Source_Ptr value 217 -- which source it refers to. Note that negative numbers are allowed to 218 -- accommodate the following special values. 219 220 No_Location : constant Source_Ptr := -1; 221 -- Value used to indicate no source position set in a node. A test for a 222 -- Source_Ptr value being > No_Location is the approved way to test for a 223 -- standard value that does not include No_Location or any of the following 224 -- special definitions. One important use of No_Location is to label 225 -- generated nodes that we don't want the debugger to see in normal mode 226 -- (very often we conditionalize so that we set No_Location in normal mode 227 -- and the corresponding source line in -gnatD mode). 228 229 Standard_Location : constant Source_Ptr := -2; 230 -- Used for all nodes in the representation of package Standard other than 231 -- nodes representing the contents of Standard.ASCII. Note that testing for 232 -- a value being <= Standard_Location tests for both Standard_Location and 233 -- for Standard_ASCII_Location. 234 235 Standard_ASCII_Location : constant Source_Ptr := -3; 236 -- Used for all nodes in the presentation of package Standard.ASCII 237 238 System_Location : constant Source_Ptr := -4; 239 -- Used to identify locations of pragmas scanned by Targparm, where we know 240 -- the location is in System, but we don't know exactly what line. 241 242 First_Source_Ptr : constant Source_Ptr := 0; 243 -- Starting source pointer index value for first source program 244 245 ------------------------------------- 246 -- Range Definitions for Tree Data -- 247 ------------------------------------- 248 249 -- The tree has fields that can hold any of the following types: 250 251 -- Pointers to other tree nodes (type Node_Id) 252 -- List pointers (type List_Id) 253 -- Element list pointers (type Elist_Id) 254 -- Names (type Name_Id) 255 -- Strings (type String_Id) 256 -- Universal integers (type Uint) 257 -- Universal reals (type Ureal) 258 259 -- In most contexts, the strongly typed interface determines which of these 260 -- types is present. However, there are some situations (involving untyped 261 -- traversals of the tree), where it is convenient to be easily able to 262 -- distinguish these values. The underlying representation in all cases is 263 -- an integer type Union_Id, and we ensure that the range of the various 264 -- possible values for each of the above types is disjoint so that this 265 -- distinction is possible. 266 267 -- Note: it is also helpful for debugging purposes to make these ranges 268 -- distinct. If a bug leads to misidentification of a value, then it will 269 -- typically result in an out of range value and a Constraint_Error. 270 271 type Union_Id is new Int; 272 -- The type in the tree for a union of possible ID values 273 274 List_Low_Bound : constant := -100_000_000; 275 -- The List_Id values are subscripts into an array of list headers which 276 -- has List_Low_Bound as its lower bound. This value is chosen so that all 277 -- List_Id values are negative, and the value zero is in the range of both 278 -- List_Id and Node_Id values (see further description below). 279 280 List_High_Bound : constant := 0; 281 -- Maximum List_Id subscript value. This allows up to 100 million list Id 282 -- values, which is in practice infinite, and there is no need to check the 283 -- range. The range overlaps the node range by one element (with value 284 -- zero), which is used both for the Empty node, and for indicating no 285 -- list. The fact that the same value is used is convenient because it 286 -- means that the default value of Empty applies to both nodes and lists, 287 -- and also is more efficient to test for. 288 289 Node_Low_Bound : constant := 0; 290 -- The tree Id values start at zero, because we use zero for Empty (to 291 -- allow a zero test for Empty). Actual tree node subscripts start at 0 292 -- since Empty is a legitimate node value. 293 294 Node_High_Bound : constant := 099_999_999; 295 -- Maximum number of nodes that can be allocated is 100 million, which 296 -- is in practice infinite, and there is no need to check the range. 297 298 Elist_Low_Bound : constant := 100_000_000; 299 -- The Elist_Id values are subscripts into an array of elist headers which 300 -- has Elist_Low_Bound as its lower bound. 301 302 Elist_High_Bound : constant := 199_999_999; 303 -- Maximum Elist_Id subscript value. This allows up to 100 million Elists, 304 -- which is in practice infinite and there is no need to check the range. 305 306 Elmt_Low_Bound : constant := 200_000_000; 307 -- Low bound of element Id values. The use of these values is internal to 308 -- the Elists package, but the definition of the range is included here 309 -- since it must be disjoint from other Id values. The Elmt_Id values are 310 -- subscripts into an array of list elements which has this as lower bound. 311 312 Elmt_High_Bound : constant := 299_999_999; 313 -- Upper bound of Elmt_Id values. This allows up to 100 million element 314 -- list members, which is in practice infinite (no range check needed). 315 316 Names_Low_Bound : constant := 300_000_000; 317 -- Low bound for name Id values 318 319 Names_High_Bound : constant := 399_999_999; 320 -- Maximum number of names that can be allocated is 100 million, which is 321 -- in practice infinite and there is no need to check the range. 322 323 Strings_Low_Bound : constant := 400_000_000; 324 -- Low bound for string Id values 325 326 Strings_High_Bound : constant := 499_999_999; 327 -- Maximum number of strings that can be allocated is 100 million, which 328 -- is in practice infinite and there is no need to check the range. 329 330 Ureal_Low_Bound : constant := 500_000_000; 331 -- Low bound for Ureal values 332 333 Ureal_High_Bound : constant := 599_999_999; 334 -- Maximum number of Ureal values stored is 100_000_000 which is in 335 -- practice infinite so that no check is required. 336 337 Uint_Low_Bound : constant := 600_000_000; 338 -- Low bound for Uint values 339 340 Uint_Table_Start : constant := 2_000_000_000; 341 -- Location where table entries for universal integers start (see 342 -- Uintp spec for details of the representation of Uint values). 343 344 Uint_High_Bound : constant := 2_099_999_999; 345 -- The range of Uint values is very large, since a substantial part 346 -- of this range is used to store direct values, see Uintp for details. 347 348 -- The following subtype definitions are used to provide convenient names 349 -- for membership tests on Int values to see what data type range they 350 -- lie in. Such tests appear only in the lowest level packages. 351 352 subtype List_Range is Union_Id 353 range List_Low_Bound .. List_High_Bound; 354 355 subtype Node_Range is Union_Id 356 range Node_Low_Bound .. Node_High_Bound; 357 358 subtype Elist_Range is Union_Id 359 range Elist_Low_Bound .. Elist_High_Bound; 360 361 subtype Elmt_Range is Union_Id 362 range Elmt_Low_Bound .. Elmt_High_Bound; 363 364 subtype Names_Range is Union_Id 365 range Names_Low_Bound .. Names_High_Bound; 366 367 subtype Strings_Range is Union_Id 368 range Strings_Low_Bound .. Strings_High_Bound; 369 370 subtype Uint_Range is Union_Id 371 range Uint_Low_Bound .. Uint_High_Bound; 372 373 subtype Ureal_Range is Union_Id 374 range Ureal_Low_Bound .. Ureal_High_Bound; 375 376 ----------------------------- 377 -- Types for Atree Package -- 378 ----------------------------- 379 380 -- Node_Id values are used to identify nodes in the tree. They are 381 -- subscripts into the Nodes table declared in package Atree. Note that 382 -- the special values Empty and Error are subscripts into this table. 383 -- See package Atree for further details. 384 385 type Node_Id is range Node_Low_Bound .. Node_High_Bound; 386 -- Type used to identify nodes in the tree 387 388 subtype Entity_Id is Node_Id; 389 -- A synonym for node types, used in the Einfo package to refer to nodes 390 -- that are entities (i.e. nodes with an Nkind of N_Defining_xxx). All such 391 -- nodes are extended nodes and these are the only extended nodes, so that 392 -- in practice entity and extended nodes are synonymous. 393 394 subtype Node_Or_Entity_Id is Node_Id; 395 -- A synonym for node types, used in cases where a given value may be used 396 -- to represent either a node or an entity. We like to minimize such uses 397 -- for obvious reasons of logical type consistency, but where such uses 398 -- occur, they should be documented by use of this type. 399 400 Empty : constant Node_Id := Node_Low_Bound; 401 -- Used to indicate null node. A node is actually allocated with this 402 -- Id value, so that Nkind (Empty) = N_Empty. Note that Node_Low_Bound 403 -- is zero, so Empty = No_List = zero. 404 405 Empty_List_Or_Node : constant := 0; 406 -- This constant is used in situations (e.g. initializing empty fields) 407 -- where the value set will be used to represent either an empty node or 408 -- a non-existent list, depending on the context. 409 410 Error : constant Node_Id := Node_Low_Bound + 1; 411 -- Used to indicate an error in the source program. A node is actually 412 -- allocated with this Id value, so that Nkind (Error) = N_Error. 413 414 Empty_Or_Error : constant Node_Id := Error; 415 -- Since Empty and Error are the first two Node_Id values, the test for 416 -- N <= Empty_Or_Error tests to see if N is Empty or Error. This definition 417 -- provides convenient self-documentation for such tests. 418 419 First_Node_Id : constant Node_Id := Node_Low_Bound; 420 -- Subscript of first allocated node. Note that Empty and Error are both 421 -- allocated nodes, whose Nkind fields can be accessed without error. 422 423 ------------------------------ 424 -- Types for Nlists Package -- 425 ------------------------------ 426 427 -- List_Id values are used to identify node lists stored in the tree, so 428 -- that each node can be on at most one such list (see package Nlists for 429 -- further details). Note that the special value Error_List is a subscript 430 -- in this table, but the value No_List is *not* a valid subscript, and any 431 -- attempt to apply list operations to No_List will cause a (detected) 432 -- error. 433 434 type List_Id is range List_Low_Bound .. List_High_Bound; 435 -- Type used to identify a node list 436 437 No_List : constant List_Id := List_High_Bound; 438 -- Used to indicate absence of a list. Note that the value is zero, which 439 -- is the same as Empty, which is helpful in initializing nodes where a 440 -- value of zero can represent either an empty node or an empty list. 441 442 Error_List : constant List_Id := List_Low_Bound; 443 -- Used to indicate that there was an error in the source program in a 444 -- context which would normally require a list. This node appears to be 445 -- an empty list to the list operations (a null list is actually allocated 446 -- which has this Id value). 447 448 First_List_Id : constant List_Id := Error_List; 449 -- Subscript of first allocated list header 450 451 ------------------------------ 452 -- Types for Elists Package -- 453 ------------------------------ 454 455 -- Element list Id values are used to identify element lists stored outside 456 -- of the tree, allowing nodes to be members of more than one such list 457 -- (see package Elists for further details). 458 459 type Elist_Id is range Elist_Low_Bound .. Elist_High_Bound; 460 -- Type used to identify an element list (Elist header table subscript) 461 462 No_Elist : constant Elist_Id := Elist_Low_Bound; 463 -- Used to indicate absence of an element list. Note that this is not an 464 -- actual Elist header, so element list operations on this value are not 465 -- valid. 466 467 First_Elist_Id : constant Elist_Id := No_Elist + 1; 468 -- Subscript of first allocated Elist header 469 470 -- Element Id values are used to identify individual elements of an element 471 -- list (see package Elists for further details). 472 473 type Elmt_Id is range Elmt_Low_Bound .. Elmt_High_Bound; 474 -- Type used to identify an element list 475 476 No_Elmt : constant Elmt_Id := Elmt_Low_Bound; 477 -- Used to represent empty element 478 479 First_Elmt_Id : constant Elmt_Id := No_Elmt + 1; 480 -- Subscript of first allocated Elmt table entry 481 482 ------------------------------- 483 -- Types for Stringt Package -- 484 ------------------------------- 485 486 -- String_Id values are used to identify entries in the strings table. They 487 -- are subscripts into the Strings table defined in package Stringt. 488 489 -- Note that with only a few exceptions, which are clearly documented, the 490 -- type String_Id should be regarded as a private type. In particular it is 491 -- never appropriate to perform arithmetic operations using this type. 492 -- Doesn't this also apply to all other *_Id types??? 493 494 type String_Id is range Strings_Low_Bound .. Strings_High_Bound; 495 -- Type used to identify entries in the strings table 496 497 No_String : constant String_Id := Strings_Low_Bound; 498 -- Used to indicate missing string Id. Note that the value zero is used 499 -- to indicate a missing data value for all the Int types in this section. 500 501 First_String_Id : constant String_Id := No_String + 1; 502 -- First subscript allocated in string table 503 504 ------------------------- 505 -- Character Code Type -- 506 ------------------------- 507 508 -- The type Char is used for character data internally in the compiler, but 509 -- character codes in the source are represented by the Char_Code type. 510 -- Each character literal in the source is interpreted as being one of the 511 -- 16#7FFF_FFFF# possible Wide_Wide_Character codes, and a unique Integer 512 -- value is assigned, corresponding to the UTF-32 value, which also 513 -- corresponds to the Pos value in the Wide_Wide_Character type, and also 514 -- corresponds to the Pos value in the Wide_Character and Character types 515 -- for values that are in appropriate range. String literals are similarly 516 -- interpreted as a sequence of such codes. 517 518 type Char_Code_Base is mod 2 ** 32; 519 for Char_Code_Base'Size use 32; 520 521 subtype Char_Code is Char_Code_Base range 0 .. 16#7FFF_FFFF#; 522 for Char_Code'Value_Size use 32; 523 for Char_Code'Object_Size use 32; 524 525 function Get_Char_Code (C : Character) return Char_Code; 526 pragma Inline (Get_Char_Code); 527 -- Function to obtain internal character code from source character. For 528 -- the moment, the internal character code is simply the Pos value of the 529 -- input source character, but we provide this interface for possible 530 -- later support of alternative character sets. 531 532 function In_Character_Range (C : Char_Code) return Boolean; 533 pragma Inline (In_Character_Range); 534 -- Determines if the given character code is in range of type Character, 535 -- and if so, returns True. If not, returns False. 536 537 function In_Wide_Character_Range (C : Char_Code) return Boolean; 538 pragma Inline (In_Wide_Character_Range); 539 -- Determines if the given character code is in range of the type 540 -- Wide_Character, and if so, returns True. If not, returns False. 541 542 function Get_Character (C : Char_Code) return Character; 543 pragma Inline (Get_Character); 544 -- For a character C that is in Character range (see above function), this 545 -- function returns the corresponding Character value. It is an error to 546 -- call Get_Character if C is not in Character range. 547 548 function Get_Wide_Character (C : Char_Code) return Wide_Character; 549 -- For a character C that is in Wide_Character range (see above function), 550 -- this function returns the corresponding Wide_Character value. It is an 551 -- error to call Get_Wide_Character if C is not in Wide_Character range. 552 553 --------------------------------------- 554 -- Types used for Library Management -- 555 --------------------------------------- 556 557 type Unit_Number_Type is new Int; 558 -- Unit number. The main source is unit 0, and subsidiary sources have 559 -- non-zero numbers starting with 1. Unit numbers are used to index the 560 -- Units table in package Lib. 561 562 Main_Unit : constant Unit_Number_Type := 0; 563 -- Unit number value for main unit 564 565 No_Unit : constant Unit_Number_Type := -1; 566 -- Special value used to signal no unit 567 568 type Source_File_Index is new Int range -1 .. Int'Last; 569 -- Type used to index the source file table (see package Sinput) 570 571 Internal_Source_File : constant Source_File_Index := 572 Source_File_Index'First; 573 -- Value used to indicate the buffer for the source-code-like strings 574 -- internally created withing the compiler (see package Sinput) 575 576 No_Source_File : constant Source_File_Index := 0; 577 -- Value used to indicate no source file present 578 579 ----------------------------------- 580 -- Representation of Time Stamps -- 581 ----------------------------------- 582 583 -- All compiled units are marked with a time stamp which is derived from 584 -- the source file (we assume that the host system has the concept of a 585 -- file time stamp which is modified when a file is modified). These 586 -- time stamps are used to ensure consistency of the set of units that 587 -- constitutes a library. Time stamps are 14-character strings with 588 -- with the following format: 589 590 -- YYYYMMDDHHMMSS 591 592 -- YYYY year 593 -- MM month (2 digits 01-12) 594 -- DD day (2 digits 01-31) 595 -- HH hour (2 digits 00-23) 596 -- MM minutes (2 digits 00-59) 597 -- SS seconds (2 digits 00-59) 598 599 -- In the case of Unix systems (and other systems which keep the time in 600 -- GMT), the time stamp is the GMT time of the file, not the local time. 601 -- This solves problems in using libraries across networks with clients 602 -- spread across multiple time-zones. 603 604 Time_Stamp_Length : constant := 14; 605 -- Length of time stamp value 606 607 subtype Time_Stamp_Index is Natural range 1 .. Time_Stamp_Length; 608 type Time_Stamp_Type is new String (Time_Stamp_Index); 609 -- Type used to represent time stamp 610 611 Empty_Time_Stamp : constant Time_Stamp_Type := (others => ' '); 612 -- Value representing an empty or missing time stamp. Looks less than any 613 -- real time stamp if two time stamps are compared. Note that although this 614 -- is not private, clients should not rely on the exact way in which this 615 -- string is represented, and instead should use the subprograms below. 616 617 Dummy_Time_Stamp : constant Time_Stamp_Type := (others => '0'); 618 -- This is used for dummy time stamp values used in the D lines for 619 -- non-existent files, and is intended to be an impossible value. 620 621 function "=" (Left, Right : Time_Stamp_Type) return Boolean; 622 function "<=" (Left, Right : Time_Stamp_Type) return Boolean; 623 function ">=" (Left, Right : Time_Stamp_Type) return Boolean; 624 function "<" (Left, Right : Time_Stamp_Type) return Boolean; 625 function ">" (Left, Right : Time_Stamp_Type) return Boolean; 626 -- Comparison functions on time stamps. Note that two time stamps are 627 -- defined as being equal if they have the same day/month/year and the 628 -- hour/minutes/seconds values are within 2 seconds of one another. This 629 -- deals with rounding effects in library file time stamps caused by 630 -- copying operations during installation. We have particularly noticed 631 -- that WinNT seems susceptible to such changes. 632 -- 633 -- Note: the Empty_Time_Stamp value looks equal to itself, and less than 634 -- any non-empty time stamp value. 635 636 procedure Split_Time_Stamp 637 (TS : Time_Stamp_Type; 638 Year : out Nat; 639 Month : out Nat; 640 Day : out Nat; 641 Hour : out Nat; 642 Minutes : out Nat; 643 Seconds : out Nat); 644 -- Given a time stamp, decompose it into its components 645 646 procedure Make_Time_Stamp 647 (Year : Nat; 648 Month : Nat; 649 Day : Nat; 650 Hour : Nat; 651 Minutes : Nat; 652 Seconds : Nat; 653 TS : out Time_Stamp_Type); 654 -- Given the components of a time stamp, initialize the value 655 656 ------------------------------------- 657 -- Types used for Check Management -- 658 ------------------------------------- 659 660 type Check_Id is new Nat; 661 -- Type used to represent a check id 662 663 No_Check_Id : constant := 0; 664 -- Check_Id value used to indicate no check 665 666 Access_Check : constant := 1; 667 Accessibility_Check : constant := 2; 668 Alignment_Check : constant := 3; 669 Allocation_Check : constant := 4; 670 Atomic_Synchronization : constant := 5; 671 Discriminant_Check : constant := 6; 672 Division_Check : constant := 7; 673 Duplicated_Tag_Check : constant := 8; 674 Elaboration_Check : constant := 9; 675 Index_Check : constant := 10; 676 Length_Check : constant := 11; 677 Overflow_Check : constant := 12; 678 Predicate_Check : constant := 13; 679 Range_Check : constant := 14; 680 Storage_Check : constant := 15; 681 Tag_Check : constant := 16; 682 Validity_Check : constant := 17; 683 Container_Checks : constant := 18; 684 Tampering_Check : constant := 19; 685 -- Values used to represent individual predefined checks (including the 686 -- setting of Atomic_Synchronization, which is implemented internally using 687 -- a "check" whose name is Atomic_Synchronization). 688 689 All_Checks : constant := 20; 690 -- Value used to represent All_Checks value 691 692 subtype Predefined_Check_Id is Check_Id range 1 .. All_Checks; 693 -- Subtype for predefined checks, including All_Checks 694 695 -- The following array contains an entry for each recognized check name 696 -- for pragma Suppress. It is used to represent current settings of scope 697 -- based suppress actions from pragma Suppress or command line settings. 698 699 -- Note: when Suppress_Array (All_Checks) is True, then generally all other 700 -- specific check entries are set True, except for the Elaboration_Check 701 -- entry which is set only if an explicit Suppress for this check is given. 702 -- The reason for this non-uniformity is that we do not want All_Checks to 703 -- suppress elaboration checking when using the static elaboration model. 704 -- We recognize only an explicit suppress of Elaboration_Check as a signal 705 -- that the static elaboration checking should skip a compile time check. 706 707 type Suppress_Array is array (Predefined_Check_Id) of Boolean; 708 pragma Pack (Suppress_Array); 709 710 -- To add a new check type to GNAT, the following steps are required: 711 712 -- 1. Add an entry to Snames spec for the new name 713 -- 2. Add an entry to the definition of Check_Id above 714 -- 3. Add a new function to Checks to handle the new check test 715 -- 4. Add a new Do_xxx_Check flag to Sinfo (if required) 716 -- 5. Add appropriate checks for the new test 717 718 -- The following provides precise details on the mode used to generate 719 -- code for intermediate operations in expressions for signed integer 720 -- arithmetic (and how to generate overflow checks if enabled). Note 721 -- that this only affects handling of intermediate results. The final 722 -- result must always fit within the target range, and if overflow 723 -- checking is enabled, the check on the final result is against this 724 -- target range. 725 726 type Overflow_Mode_Type is ( 727 Not_Set, 728 -- Dummy value used during initialization process to show that the 729 -- corresponding value has not yet been initialized. 730 731 Strict, 732 -- Operations are done in the base type of the subexpression. If 733 -- overflow checks are enabled, then the check is against the range 734 -- of this base type. 735 736 Minimized, 737 -- Where appropriate, intermediate arithmetic operations are performed 738 -- with an extended range, using Long_Long_Integer if necessary. If 739 -- overflow checking is enabled, then the check is against the range 740 -- of Long_Long_Integer. 741 742 Eliminated); 743 -- In this mode arbitrary precision arithmetic is used as needed to 744 -- ensure that it is impossible for intermediate arithmetic to cause an 745 -- overflow. In this mode, intermediate expressions are not affected by 746 -- the overflow checking mode, since overflows are eliminated. 747 748 subtype Minimized_Or_Eliminated is 749 Overflow_Mode_Type range Minimized .. Eliminated; 750 -- Define subtype so that clients don't need to know ordering. Note that 751 -- Overflow_Mode_Type is not marked as an ordered enumeration type. 752 753 -- The following structure captures the state of check suppression or 754 -- activation at a particular point in the program execution. 755 756 type Suppress_Record is record 757 Suppress : Suppress_Array; 758 -- Indicates suppression status of each possible check 759 760 Overflow_Mode_General : Overflow_Mode_Type; 761 -- This field indicates the mode for handling code generation and 762 -- overflow checking (if enabled) for intermediate expression values. 763 -- This applies to general expressions outside assertions. 764 765 Overflow_Mode_Assertions : Overflow_Mode_Type; 766 -- This field indicates the mode for handling code generation and 767 -- overflow checking (if enabled) for intermediate expression values. 768 -- This applies to any expression occuring inside assertions. 769 end record; 770 771 ----------------------------------- 772 -- Global Exception Declarations -- 773 ----------------------------------- 774 775 -- This section contains declarations of exceptions that are used 776 -- throughout the compiler or in other GNAT tools. 777 778 Unrecoverable_Error : exception; 779 -- This exception is raised to immediately terminate the compilation of the 780 -- current source program. Used in situations where things are bad enough 781 -- that it doesn't seem worth continuing (e.g. max errors reached, or a 782 -- required file is not found). Also raised when the compiler finds itself 783 -- in trouble after an error (see Comperr). 784 785 Terminate_Program : exception; 786 -- This exception is raised to immediately terminate the tool being 787 -- executed. Each tool where this exception may be raised must have a 788 -- single exception handler that contains only a null statement and that is 789 -- the last statement of the program. If needed, procedure Set_Exit_Status 790 -- is called with the appropriate exit status before raising 791 -- Terminate_Program. 792 793 --------------------------------- 794 -- Parameter Mechanism Control -- 795 --------------------------------- 796 797 -- Function and parameter entities have a field that records the passing 798 -- mechanism. See specification of Sem_Mech for full details. The following 799 -- subtype is used to represent values of this type: 800 801 subtype Mechanism_Type is Int range -2 .. Int'Last; 802 -- Type used to represent a mechanism value. This is a subtype rather than 803 -- a type to avoid some annoying processing problems with certain routines 804 -- in Einfo (processing them to create the corresponding C). The values in 805 -- the range -2 .. 0 are used to represent mechanism types declared as 806 -- named constants in the spec of Sem_Mech. Positive values are used for 807 -- the case of a pragma C_Pass_By_Copy that sets a threshold value for the 808 -- mechanism to be used. For example if pragma C_Pass_By_Copy (32) is given 809 -- then Default_C_Record_Mechanism is set to 32, and the meaning is to use 810 -- By_Reference if the size is greater than 32, and By_Copy otherwise. 811 812 ------------------------------ 813 -- Run-Time Exception Codes -- 814 ------------------------------ 815 816 -- When the code generator generates a run-time exception, it provides a 817 -- reason code which is one of the following. This reason code is used to 818 -- select the appropriate run-time routine to be called, determining both 819 -- the exception to be raised, and the message text to be added. 820 821 -- The prefix CE/PE/SE indicates the exception to be raised 822 -- CE = Constraint_Error 823 -- PE = Program_Error 824 -- SE = Storage_Error 825 826 -- The remaining part of the name indicates the message text to be added, 827 -- where all letters are lower case, and underscores are converted to 828 -- spaces (for example CE_Invalid_Data adds the text "invalid data"). 829 830 -- To add a new code, you need to do the following: 831 832 -- 1. Assign a new number to the reason. Do not renumber existing codes, 833 -- since this causes compatibility/bootstrap issues, so always add the 834 -- new code at the end of the list. 835 836 -- 2. Update the contents of the array Kind 837 838 -- 3. Modify the corresponding definitions in types.h, including the 839 -- definition of last_reason_code. 840 841 -- 4. Add the name of the routines in exp_ch11.Get_RT_Exception_Name 842 843 -- 5. Add a new routine in Ada.Exceptions with the appropriate call and 844 -- static string constant. Note that there is more than one version 845 -- of a-except.adb which must be modified. 846 847 -- Note on ordering of references. For the tables in Ada.Exceptions units, 848 -- usually the ordering does not matter, and we use the same ordering as 849 -- is used here (note the requirement in the ordering here that CE/PE/SE 850 -- codes be kept together, so the subtype declarations work OK). 851 852 type RT_Exception_Code is 853 (CE_Access_Check_Failed, -- 00 854 CE_Access_Parameter_Is_Null, -- 01 855 CE_Discriminant_Check_Failed, -- 02 856 CE_Divide_By_Zero, -- 03 857 CE_Explicit_Raise, -- 04 858 CE_Index_Check_Failed, -- 05 859 CE_Invalid_Data, -- 06 860 CE_Length_Check_Failed, -- 07 861 CE_Null_Exception_Id, -- 08 862 CE_Null_Not_Allowed, -- 09 863 864 CE_Overflow_Check_Failed, -- 10 865 CE_Partition_Check_Failed, -- 11 866 CE_Range_Check_Failed, -- 12 867 CE_Tag_Check_Failed, -- 13 868 PE_Access_Before_Elaboration, -- 14 869 PE_Accessibility_Check_Failed, -- 15 870 PE_Address_Of_Intrinsic, -- 16 871 PE_Aliased_Parameters, -- 17 872 PE_All_Guards_Closed, -- 18 873 PE_Bad_Predicated_Generic_Type, -- 19 874 875 PE_Current_Task_In_Entry_Body, -- 20 876 PE_Duplicated_Entry_Address, -- 21 877 PE_Explicit_Raise, -- 22 878 PE_Finalize_Raised_Exception, -- 23 879 PE_Implicit_Return, -- 24 880 PE_Misaligned_Address_Value, -- 25 881 PE_Missing_Return, -- 26 882 PE_Overlaid_Controlled_Object, -- 27 883 PE_Potentially_Blocking_Operation, -- 28 884 PE_Stubbed_Subprogram_Called, -- 29 885 886 PE_Unchecked_Union_Restriction, -- 30 887 PE_Non_Transportable_Actual, -- 31 888 SE_Empty_Storage_Pool, -- 32 889 SE_Explicit_Raise, -- 33 890 SE_Infinite_Recursion, -- 34 891 SE_Object_Too_Large, -- 35 892 PE_Stream_Operation_Not_Allowed); -- 36 893 894 Last_Reason_Code : constant := 36; 895 -- Last reason code 896 897 type Reason_Kind is (CE_Reason, PE_Reason, SE_Reason); 898 -- Categorization of reason codes by exception raised 899 900 Rkind : constant array (RT_Exception_Code range <>) of Reason_Kind := 901 (CE_Access_Check_Failed => CE_Reason, 902 CE_Access_Parameter_Is_Null => CE_Reason, 903 CE_Discriminant_Check_Failed => CE_Reason, 904 CE_Divide_By_Zero => CE_Reason, 905 CE_Explicit_Raise => CE_Reason, 906 CE_Index_Check_Failed => CE_Reason, 907 CE_Invalid_Data => CE_Reason, 908 CE_Length_Check_Failed => CE_Reason, 909 CE_Null_Exception_Id => CE_Reason, 910 CE_Null_Not_Allowed => CE_Reason, 911 CE_Overflow_Check_Failed => CE_Reason, 912 CE_Partition_Check_Failed => CE_Reason, 913 CE_Range_Check_Failed => CE_Reason, 914 CE_Tag_Check_Failed => CE_Reason, 915 916 PE_Access_Before_Elaboration => PE_Reason, 917 PE_Accessibility_Check_Failed => PE_Reason, 918 PE_Address_Of_Intrinsic => PE_Reason, 919 PE_Aliased_Parameters => PE_Reason, 920 PE_All_Guards_Closed => PE_Reason, 921 PE_Bad_Predicated_Generic_Type => PE_Reason, 922 PE_Current_Task_In_Entry_Body => PE_Reason, 923 PE_Duplicated_Entry_Address => PE_Reason, 924 PE_Explicit_Raise => PE_Reason, 925 PE_Finalize_Raised_Exception => PE_Reason, 926 PE_Implicit_Return => PE_Reason, 927 PE_Misaligned_Address_Value => PE_Reason, 928 PE_Missing_Return => PE_Reason, 929 PE_Overlaid_Controlled_Object => PE_Reason, 930 PE_Potentially_Blocking_Operation => PE_Reason, 931 PE_Stubbed_Subprogram_Called => PE_Reason, 932 PE_Unchecked_Union_Restriction => PE_Reason, 933 PE_Non_Transportable_Actual => PE_Reason, 934 PE_Stream_Operation_Not_Allowed => PE_Reason, 935 936 SE_Empty_Storage_Pool => SE_Reason, 937 SE_Explicit_Raise => SE_Reason, 938 SE_Infinite_Recursion => SE_Reason, 939 SE_Object_Too_Large => SE_Reason); 940 941end Types; 942