gcc/ada/libgnat/s-auxdec.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                       S Y S T E M . A U X _ D E C                        --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1996-2023, 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 definitions that are designed to be compatible
  33 --  with the extra definitions in package System for DEC Ada implementations.
  34
  35 --  These definitions can be used directly by withing this package, or merged
  36 --  with System using pragma Extend_System (Aux_DEC)
  37
  38 with Ada.Unchecked_Conversion;
  39
  40 package System.Aux_DEC is
  41    pragma Preelaborate;
  42
  43    subtype Short_Address is Address;
  44    --  For compatibility with systems having short and long addresses
  45
  46    type Integer_8  is range -2 **  (8 - 1) .. +2 **  (8 - 1) - 1;
  47    for Integer_8'Size  use  8;
  48
  49    type Integer_16 is range -2 ** (16 - 1) .. +2 ** (16 - 1) - 1;
  50    for Integer_16'Size use 16;
  51
  52    type Integer_32 is range -2 ** (32 - 1) .. +2 ** (32 - 1) - 1;
  53    for Integer_32'Size use 32;
  54
  55    type Integer_64 is range -2 ** (64 - 1) .. +2 ** (64 - 1) - 1;
  56    for Integer_64'Size use 64;
  57
  58    type Integer_8_Array  is array (Integer range <>) of Integer_8;
  59    type Integer_16_Array is array (Integer range <>) of Integer_16;
  60    type Integer_32_Array is array (Integer range <>) of Integer_32;
  61    type Integer_64_Array is array (Integer range <>) of Integer_64;
  62    --  These array types are not in all versions of DEC System, and in fact it
  63    --  is not quite clear why they are in some and not others, but since they
  64    --  definitely appear in some versions, we include them unconditionally.
  65
  66    type Largest_Integer is range Min_Int .. Max_Int;
  67
  68    type AST_Handler is private;
  69
  70    No_AST_Handler : constant AST_Handler;
  71
  72    type Type_Class is
  73      (Type_Class_Enumeration,
  74       Type_Class_Integer,
  75       Type_Class_Fixed_Point,
  76       Type_Class_Floating_Point,
  77       Type_Class_Array,
  78       Type_Class_Record,
  79       Type_Class_Access,
  80       Type_Class_Task,             -- also in Ada 95 protected
  81       Type_Class_Address);
  82
  83    function "not" (Left        : Largest_Integer) return Largest_Integer;
  84    function "and" (Left, Right : Largest_Integer) return Largest_Integer;
  85    function "or"  (Left, Right : Largest_Integer) return Largest_Integer;
  86    function "xor" (Left, Right : Largest_Integer) return Largest_Integer;
  87
  88    Address_Zero       : constant Address;
  89    No_Addr            : constant Address;
  90    Address_Size       : constant := Standard'Address_Size;
  91    Short_Address_Size : constant := Standard'Address_Size;
  92
  93    function "+" (Left : Address; Right : Integer) return Address;
  94    function "+" (Left : Integer; Right : Address) return Address;
  95    function "-" (Left : Address; Right : Address) return Integer;
  96    function "-" (Left : Address; Right : Integer) return Address;
  97
  98    generic
  99       type Target is private;
 100    function Fetch_From_Address (A : Address) return Target;
 101
 102    generic
 103       type Target is private;
 104    procedure Assign_To_Address (A : Address; T : Target);
 105
 106    --  Floating point type declarations for VAX floating point data types
 107
 108    type F_Float is digits 6;
 109    type D_Float is digits 9;
 110    type G_Float is digits 15;
 111    --  We provide the type names, but these will be IEEE format, not VAX format
 112
 113    --  Floating point type declarations for IEEE floating point data types
 114
 115    type IEEE_Single_Float is digits 6;
 116    type IEEE_Double_Float is digits 15;
 117
 118    Non_Ada_Error : exception;
 119
 120    --  Hardware-oriented types and functions
 121
 122    type Bit_Array is array (Integer range <>) of Boolean;
 123    pragma Pack (Bit_Array);
 124
 125    subtype Bit_Array_8  is Bit_Array (0 ..  7);
 126    subtype Bit_Array_16 is Bit_Array (0 .. 15);
 127    subtype Bit_Array_32 is Bit_Array (0 .. 31);
 128    subtype Bit_Array_64 is Bit_Array (0 .. 63);
 129
 130    type Unsigned_Byte is range 0 .. 255;
 131    for  Unsigned_Byte'Size use 8;
 132
 133    function "not" (Left        : Unsigned_Byte) return Unsigned_Byte;
 134    function "and" (Left, Right : Unsigned_Byte) return Unsigned_Byte;
 135    function "or"  (Left, Right : Unsigned_Byte) return Unsigned_Byte;
 136    function "xor" (Left, Right : Unsigned_Byte) return Unsigned_Byte;
 137
 138    function To_Unsigned_Byte (X : Bit_Array_8) return Unsigned_Byte;
 139    function To_Bit_Array_8   (X : Unsigned_Byte) return Bit_Array_8;
 140
 141    type Unsigned_Byte_Array is array (Integer range <>) of Unsigned_Byte;
 142
 143    type Unsigned_Word is range 0 .. 65535;
 144    for  Unsigned_Word'Size use 16;
 145
 146    function "not" (Left        : Unsigned_Word) return Unsigned_Word;
 147    function "and" (Left, Right : Unsigned_Word) return Unsigned_Word;
 148    function "or"  (Left, Right : Unsigned_Word) return Unsigned_Word;
 149    function "xor" (Left, Right : Unsigned_Word) return Unsigned_Word;
 150
 151    function To_Unsigned_Word (X : Bit_Array_16) return Unsigned_Word;
 152    function To_Bit_Array_16  (X : Unsigned_Word) return Bit_Array_16;
 153
 154    type Unsigned_Word_Array is array (Integer range <>) of Unsigned_Word;
 155
 156    type Unsigned_Longword is range -2_147_483_648 .. 2_147_483_647;
 157    for  Unsigned_Longword'Size use 32;
 158
 159    function "not" (Left        : Unsigned_Longword) return Unsigned_Longword;
 160    function "and" (Left, Right : Unsigned_Longword) return Unsigned_Longword;
 161    function "or"  (Left, Right : Unsigned_Longword) return Unsigned_Longword;
 162    function "xor" (Left, Right : Unsigned_Longword) return Unsigned_Longword;
 163
 164    function To_Unsigned_Longword (X : Bit_Array_32) return Unsigned_Longword;
 165    function To_Bit_Array_32 (X : Unsigned_Longword) return Bit_Array_32;
 166
 167    type Unsigned_Longword_Array is
 168       array (Integer range <>) of Unsigned_Longword;
 169
 170    type Unsigned_32 is range 0 .. 4_294_967_295;
 171    for  Unsigned_32'Size use 32;
 172
 173    function "not" (Left        : Unsigned_32) return Unsigned_32;
 174    function "and" (Left, Right : Unsigned_32) return Unsigned_32;
 175    function "or"  (Left, Right : Unsigned_32) return Unsigned_32;
 176    function "xor" (Left, Right : Unsigned_32) return Unsigned_32;
 177
 178    function To_Unsigned_32 (X : Bit_Array_32) return Unsigned_32;
 179    function To_Bit_Array_32 (X : Unsigned_32) return Bit_Array_32;
 180
 181    type Unsigned_Quadword is record
 182       L0 : Unsigned_Longword;
 183       L1 : Unsigned_Longword;
 184    end record;
 185
 186    for Unsigned_Quadword'Size      use 64;
 187    for Unsigned_Quadword'Alignment use
 188      Integer'Min (8, Standard'Maximum_Alignment);
 189
 190    function "not" (Left        : Unsigned_Quadword) return Unsigned_Quadword;
 191    function "and" (Left, Right : Unsigned_Quadword) return Unsigned_Quadword;
 192    function "or"  (Left, Right : Unsigned_Quadword) return Unsigned_Quadword;
 193    function "xor" (Left, Right : Unsigned_Quadword) return Unsigned_Quadword;
 194
 195    function To_Unsigned_Quadword (X : Bit_Array_64) return Unsigned_Quadword;
 196    function To_Bit_Array_64 (X : Unsigned_Quadword) return Bit_Array_64;
 197
 198    type Unsigned_Quadword_Array is
 199       array (Integer range <>) of Unsigned_Quadword;
 200
 201    subtype Address_Int is Integer;
 202
 203    function To_Address (X : Integer) return Address;
 204    pragma Pure_Function (To_Address);
 205
 206    function To_Address_Long (X : Unsigned_Longword) return Address;
 207    pragma Pure_Function (To_Address_Long);
 208
 209    function To_Integer (X : Address) return Integer;
 210
 211    function To_Unsigned_Longword (X : Address)     return Unsigned_Longword;
 212    function To_Unsigned_Longword (X : AST_Handler) return Unsigned_Longword;
 213
 214    --  Conventional names for static subtypes of type UNSIGNED_LONGWORD
 215
 216    subtype Unsigned_1  is Unsigned_Longword range 0 .. 2** 1 - 1;
 217    subtype Unsigned_2  is Unsigned_Longword range 0 .. 2** 2 - 1;
 218    subtype Unsigned_3  is Unsigned_Longword range 0 .. 2** 3 - 1;
 219    subtype Unsigned_4  is Unsigned_Longword range 0 .. 2** 4 - 1;
 220    subtype Unsigned_5  is Unsigned_Longword range 0 .. 2** 5 - 1;
 221    subtype Unsigned_6  is Unsigned_Longword range 0 .. 2** 6 - 1;
 222    subtype Unsigned_7  is Unsigned_Longword range 0 .. 2** 7 - 1;
 223    subtype Unsigned_8  is Unsigned_Longword range 0 .. 2** 8 - 1;
 224    subtype Unsigned_9  is Unsigned_Longword range 0 .. 2** 9 - 1;
 225    subtype Unsigned_10 is Unsigned_Longword range 0 .. 2**10 - 1;
 226    subtype Unsigned_11 is Unsigned_Longword range 0 .. 2**11 - 1;
 227    subtype Unsigned_12 is Unsigned_Longword range 0 .. 2**12 - 1;
 228    subtype Unsigned_13 is Unsigned_Longword range 0 .. 2**13 - 1;
 229    subtype Unsigned_14 is Unsigned_Longword range 0 .. 2**14 - 1;
 230    subtype Unsigned_15 is Unsigned_Longword range 0 .. 2**15 - 1;
 231    subtype Unsigned_16 is Unsigned_Longword range 0 .. 2**16 - 1;
 232    subtype Unsigned_17 is Unsigned_Longword range 0 .. 2**17 - 1;
 233    subtype Unsigned_18 is Unsigned_Longword range 0 .. 2**18 - 1;
 234    subtype Unsigned_19 is Unsigned_Longword range 0 .. 2**19 - 1;
 235    subtype Unsigned_20 is Unsigned_Longword range 0 .. 2**20 - 1;
 236    subtype Unsigned_21 is Unsigned_Longword range 0 .. 2**21 - 1;
 237    subtype Unsigned_22 is Unsigned_Longword range 0 .. 2**22 - 1;
 238    subtype Unsigned_23 is Unsigned_Longword range 0 .. 2**23 - 1;
 239    subtype Unsigned_24 is Unsigned_Longword range 0 .. 2**24 - 1;
 240    subtype Unsigned_25 is Unsigned_Longword range 0 .. 2**25 - 1;
 241    subtype Unsigned_26 is Unsigned_Longword range 0 .. 2**26 - 1;
 242    subtype Unsigned_27 is Unsigned_Longword range 0 .. 2**27 - 1;
 243    subtype Unsigned_28 is Unsigned_Longword range 0 .. 2**28 - 1;
 244    subtype Unsigned_29 is Unsigned_Longword range 0 .. 2**29 - 1;
 245    subtype Unsigned_30 is Unsigned_Longword range 0 .. 2**30 - 1;
 246    subtype Unsigned_31 is Unsigned_Longword range 0 .. 2**31 - 1;
 247
 248    --  Function for obtaining global symbol values
 249
 250    function Import_Value         (Symbol : String) return Unsigned_Longword;
 251    function Import_Address       (Symbol : String) return Address;
 252    function Import_Largest_Value (Symbol : String) return Largest_Integer;
 253
 254    pragma Import (Intrinsic, Import_Value);
 255    pragma Import (Intrinsic, Import_Address);
 256    pragma Import (Intrinsic, Import_Largest_Value);
 257
 258    --  For the following declarations, note that the declaration without a
 259    --  Retry_Count parameter means to retry infinitely. A value of zero for
 260    --  the Retry_Count parameter means do not retry.
 261
 262    --  Interlocked-instruction procedures
 263
 264    procedure Clear_Interlocked
 265      (Bit       : in out Boolean;
 266       Old_Value : out Boolean);
 267
 268    procedure Set_Interlocked
 269      (Bit       : in out Boolean;
 270       Old_Value : out Boolean);
 271
 272    type Aligned_Word is record
 273       Value : Short_Integer;
 274    end record;
 275
 276    for Aligned_Word'Alignment use Integer'Min (2, Standard'Maximum_Alignment);
 277
 278    procedure Clear_Interlocked
 279      (Bit          : in out Boolean;
 280       Old_Value    : out Boolean;
 281       Retry_Count  : Natural;
 282       Success_Flag : out Boolean);
 283
 284    procedure Set_Interlocked
 285      (Bit          : in out Boolean;
 286       Old_Value    : out Boolean;
 287       Retry_Count  : Natural;
 288       Success_Flag : out Boolean);
 289
 290    procedure Add_Interlocked
 291      (Addend       : Short_Integer;
 292       Augend       : in out Aligned_Word;
 293       Sign         : out Integer);
 294
 295    type Aligned_Integer is record
 296       Value : Integer;
 297    end record;
 298
 299    for Aligned_Integer'Alignment use
 300      Integer'Min (4, Standard'Maximum_Alignment);
 301
 302    type Aligned_Long_Integer is record
 303       Value : Long_Integer;
 304    end record;
 305
 306    for Aligned_Long_Integer'Alignment use
 307      Integer'Min (8, Standard'Maximum_Alignment);
 308
 309    --  For the following declarations, note that the declaration without a
 310    --  Retry_Count parameter mean to retry infinitely. A value of zero for
 311    --  the Retry_Count means do not retry.
 312
 313    procedure Add_Atomic
 314      (To           : in out Aligned_Integer;
 315       Amount       : Integer);
 316
 317    procedure Add_Atomic
 318      (To           : in out Aligned_Integer;
 319       Amount       : Integer;
 320       Retry_Count  : Natural;
 321       Old_Value    : out Integer;
 322       Success_Flag : out Boolean);
 323
 324    procedure Add_Atomic
 325      (To           : in out Aligned_Long_Integer;
 326       Amount       : Long_Integer);
 327
 328    procedure Add_Atomic
 329      (To           : in out Aligned_Long_Integer;
 330       Amount       : Long_Integer;
 331       Retry_Count  : Natural;
 332       Old_Value    : out Long_Integer;
 333       Success_Flag : out Boolean);
 334
 335    procedure And_Atomic
 336      (To           : in out Aligned_Integer;
 337       From         : Integer);
 338
 339    procedure And_Atomic
 340      (To           : in out Aligned_Integer;
 341       From         : Integer;
 342       Retry_Count  : Natural;
 343       Old_Value    : out Integer;
 344       Success_Flag : out Boolean);
 345
 346    procedure And_Atomic
 347      (To           : in out Aligned_Long_Integer;
 348       From         : Long_Integer);
 349
 350    procedure And_Atomic
 351      (To           : in out Aligned_Long_Integer;
 352       From         : Long_Integer;
 353       Retry_Count  : Natural;
 354       Old_Value    : out Long_Integer;
 355       Success_Flag : out Boolean);
 356
 357    procedure Or_Atomic
 358      (To           : in out Aligned_Integer;
 359       From         : Integer);
 360
 361    procedure Or_Atomic
 362      (To           : in out Aligned_Integer;
 363       From         : Integer;
 364       Retry_Count  : Natural;
 365       Old_Value    : out Integer;
 366       Success_Flag : out Boolean);
 367
 368    procedure Or_Atomic
 369      (To           : in out Aligned_Long_Integer;
 370       From         : Long_Integer);
 371
 372    procedure Or_Atomic
 373      (To           : in out Aligned_Long_Integer;
 374       From         : Long_Integer;
 375       Retry_Count  : Natural;
 376       Old_Value    : out Long_Integer;
 377       Success_Flag : out Boolean);
 378
 379    type Insq_Status is (Fail_No_Lock, OK_Not_First, OK_First);
 380
 381    for Insq_Status use
 382      (Fail_No_Lock => -1,
 383       OK_Not_First =>  0,
 384       OK_First     => +1);
 385
 386    type Remq_Status is (
 387      Fail_No_Lock,
 388      Fail_Was_Empty,
 389      OK_Not_Empty,
 390      OK_Empty);
 391
 392    for Remq_Status use
 393      (Fail_No_Lock   => -1,
 394       Fail_Was_Empty =>  0,
 395       OK_Not_Empty   => +1,
 396       OK_Empty       => +2);
 397
 398    procedure Insqhi
 399      (Item   : Address;
 400       Header : Address;
 401       Status : out Insq_Status);
 402
 403    procedure Remqhi
 404      (Header : Address;
 405       Item   : out Address;
 406       Status : out Remq_Status);
 407
 408    procedure Insqti
 409      (Item   : Address;
 410       Header : Address;
 411       Status : out Insq_Status);
 412
 413    procedure Remqti
 414      (Header : Address;
 415       Item   : out Address;
 416       Status : out Remq_Status);
 417
 418 private
 419
 420    Address_Zero : constant Address := Null_Address;
 421    No_Addr      : constant Address := Null_Address;
 422
 423    --  An AST_Handler value is from a typing point of view simply a pointer
 424    --  to a procedure taking a single 64 bit parameter. However, this
 425    --  is a bit misleading, because the data that this pointer references is
 426    --  highly stylized. See body of System.AST_Handling for full details.
 427
 428    type AST_Handler is access procedure (Param : Long_Integer);
 429    No_AST_Handler : constant AST_Handler := null;
 430
 431    --  Other operators have incorrect profiles. It would be nice to make
 432    --  them intrinsic, since the backend can handle them, but the front
 433    --  end is not prepared to deal with them, so at least inline them.
 434
 435    pragma Inline_Always ("+");
 436    pragma Inline_Always ("-");
 437    pragma Inline_Always ("not");
 438    pragma Inline_Always ("and");
 439    pragma Inline_Always ("or");
 440    pragma Inline_Always ("xor");
 441
 442    --  Other inlined subprograms
 443
 444    pragma Inline_Always (Fetch_From_Address);
 445    pragma Inline_Always (Assign_To_Address);
 446
 447    --  Synchronization related subprograms. Mechanism is explicitly set
 448    --  so that the critical parameters are passed by reference.
 449    --  Without this, the parameters are passed by copy, creating load/store
 450    --  race conditions. We also inline them, since this seems more in the
 451    --  spirit of the original (hardware intrinsic) routines.
 452
 453    pragma Export_Procedure
 454      (Clear_Interlocked,
 455       External        => "system__aux_dec__clear_interlocked__1",
 456       Parameter_Types => (Boolean, Boolean),
 457       Mechanism       => (Reference, Reference));
 458    pragma Export_Procedure
 459      (Clear_Interlocked,
 460       External        => "system__aux_dec__clear_interlocked__2",
 461       Parameter_Types => (Boolean, Boolean, Natural, Boolean),
 462       Mechanism       => (Reference, Reference, Value, Reference));
 463    pragma Inline_Always (Clear_Interlocked);
 464
 465    pragma Export_Procedure
 466      (Set_Interlocked,
 467       External        => "system__aux_dec__set_interlocked__1",
 468       Parameter_Types => (Boolean, Boolean),
 469       Mechanism       => (Reference, Reference));
 470    pragma Export_Procedure
 471      (Set_Interlocked,
 472       External        => "system__aux_dec__set_interlocked__2",
 473       Parameter_Types => (Boolean, Boolean, Natural, Boolean),
 474       Mechanism       => (Reference, Reference, Value, Reference));
 475    pragma Inline_Always (Set_Interlocked);
 476
 477    pragma Export_Procedure
 478      (Add_Interlocked,
 479       External        => "system__aux_dec__add_interlocked__1",
 480       Mechanism       => (Value, Reference, Reference));
 481    pragma Inline_Always (Add_Interlocked);
 482
 483    pragma Export_Procedure
 484      (Add_Atomic,
 485       External        => "system__aux_dec__add_atomic__1",
 486       Parameter_Types => (Aligned_Integer, Integer),
 487       Mechanism       => (Reference, Value));
 488    pragma Export_Procedure
 489      (Add_Atomic,
 490       External        => "system__aux_dec__add_atomic__2",
 491       Parameter_Types => (Aligned_Integer, Integer, Natural, Integer, Boolean),
 492       Mechanism       => (Reference, Value, Value, Reference, Reference));
 493    pragma Export_Procedure
 494      (Add_Atomic,
 495       External        => "system__aux_dec__add_atomic__3",
 496       Parameter_Types => (Aligned_Long_Integer, Long_Integer),
 497       Mechanism       => (Reference, Value));
 498    pragma Export_Procedure
 499      (Add_Atomic,
 500       External        => "system__aux_dec__add_atomic__4",
 501       Parameter_Types => (Aligned_Long_Integer, Long_Integer, Natural,
 502                           Long_Integer, Boolean),
 503       Mechanism       => (Reference, Value, Value, Reference, Reference));
 504    pragma Inline_Always (Add_Atomic);
 505
 506    pragma Export_Procedure
 507      (And_Atomic,
 508       External        => "system__aux_dec__and_atomic__1",
 509       Parameter_Types => (Aligned_Integer, Integer),
 510       Mechanism       => (Reference, Value));
 511    pragma Export_Procedure
 512      (And_Atomic,
 513       External        => "system__aux_dec__and_atomic__2",
 514       Parameter_Types => (Aligned_Integer, Integer, Natural, Integer, Boolean),
 515       Mechanism       => (Reference, Value, Value, Reference, Reference));
 516    pragma Export_Procedure
 517      (And_Atomic,
 518       External => "system__aux_dec__and_atomic__3",
 519       Parameter_Types => (Aligned_Long_Integer, Long_Integer),
 520       Mechanism => (Reference, Value));
 521    pragma Export_Procedure
 522      (And_Atomic,
 523       External        => "system__aux_dec__and_atomic__4",
 524       Parameter_Types => (Aligned_Long_Integer, Long_Integer, Natural,
 525                           Long_Integer, Boolean),
 526       Mechanism       => (Reference, Value, Value, Reference, Reference));
 527    pragma Inline_Always (And_Atomic);
 528
 529    pragma Export_Procedure
 530      (Or_Atomic,
 531       External        => "system__aux_dec__or_atomic__1",
 532       Parameter_Types => (Aligned_Integer, Integer),
 533       Mechanism       => (Reference, Value));
 534    pragma Export_Procedure
 535      (Or_Atomic,
 536       External        => "system__aux_dec__or_atomic__2",
 537       Parameter_Types => (Aligned_Integer, Integer, Natural, Integer, Boolean),
 538       Mechanism       => (Reference, Value, Value, Reference, Reference));
 539    pragma Export_Procedure
 540      (Or_Atomic,
 541       External        => "system__aux_dec__or_atomic__3",
 542       Parameter_Types => (Aligned_Long_Integer, Long_Integer),
 543       Mechanism       => (Reference, Value));
 544    pragma Export_Procedure
 545      (Or_Atomic,
 546       External        => "system__aux_dec__or_atomic__4",
 547       Parameter_Types => (Aligned_Long_Integer, Long_Integer, Natural,
 548                           Long_Integer, Boolean),
 549       Mechanism       => (Reference, Value, Value, Reference, Reference));
 550    pragma Inline_Always (Or_Atomic);
 551
 552    --  Provide proper unchecked conversion definitions for transfer
 553    --  functions. Note that we need this level of indirection because
 554    --  the formal parameter name is X and not Source (and this is indeed
 555    --  detectable by a program)
 556
 557    function To_Unsigned_Byte_A is new
 558      Ada.Unchecked_Conversion (Bit_Array_8, Unsigned_Byte);
 559
 560    function To_Unsigned_Byte (X : Bit_Array_8) return Unsigned_Byte
 561      renames To_Unsigned_Byte_A;
 562
 563    function To_Bit_Array_8_A is new
 564      Ada.Unchecked_Conversion (Unsigned_Byte, Bit_Array_8);
 565
 566    function To_Bit_Array_8 (X : Unsigned_Byte) return Bit_Array_8
 567      renames To_Bit_Array_8_A;
 568
 569    function To_Unsigned_Word_A is new
 570      Ada.Unchecked_Conversion (Bit_Array_16, Unsigned_Word);
 571
 572    function To_Unsigned_Word (X : Bit_Array_16) return Unsigned_Word
 573      renames To_Unsigned_Word_A;
 574
 575    function To_Bit_Array_16_A is new
 576      Ada.Unchecked_Conversion (Unsigned_Word, Bit_Array_16);
 577
 578    function To_Bit_Array_16 (X : Unsigned_Word) return Bit_Array_16
 579      renames To_Bit_Array_16_A;
 580
 581    function To_Unsigned_Longword_A is new
 582      Ada.Unchecked_Conversion (Bit_Array_32, Unsigned_Longword);
 583
 584    function To_Unsigned_Longword (X : Bit_Array_32) return Unsigned_Longword
 585      renames To_Unsigned_Longword_A;
 586
 587    function To_Bit_Array_32_A is new
 588      Ada.Unchecked_Conversion (Unsigned_Longword, Bit_Array_32);
 589
 590    function To_Bit_Array_32 (X : Unsigned_Longword) return Bit_Array_32
 591      renames To_Bit_Array_32_A;
 592
 593    function To_Unsigned_32_A is new
 594      Ada.Unchecked_Conversion (Bit_Array_32, Unsigned_32);
 595
 596    function To_Unsigned_32 (X : Bit_Array_32) return Unsigned_32
 597      renames To_Unsigned_32_A;
 598
 599    function To_Bit_Array_32_A is new
 600      Ada.Unchecked_Conversion (Unsigned_32, Bit_Array_32);
 601
 602    function To_Bit_Array_32 (X : Unsigned_32) return Bit_Array_32
 603      renames To_Bit_Array_32_A;
 604
 605    function To_Unsigned_Quadword_A is new
 606      Ada.Unchecked_Conversion (Bit_Array_64, Unsigned_Quadword);
 607
 608    function To_Unsigned_Quadword (X : Bit_Array_64) return Unsigned_Quadword
 609      renames To_Unsigned_Quadword_A;
 610
 611    function To_Bit_Array_64_A is new
 612      Ada.Unchecked_Conversion (Unsigned_Quadword, Bit_Array_64);
 613
 614    function To_Bit_Array_64 (X : Unsigned_Quadword) return Bit_Array_64
 615      renames To_Bit_Array_64_A;
 616
 617    pragma Warnings (Off);
 618    --  Turn warnings off. This is needed for systems with 64-bit integers,
 619    --  where some of these operations are of dubious meaning, but we do not
 620    --  want warnings when we compile on such systems.
 621
 622    function To_Address_A is new
 623      Ada.Unchecked_Conversion (Integer, Address);
 624    pragma Pure_Function (To_Address_A);
 625
 626    function To_Address (X : Integer) return Address
 627      renames To_Address_A;
 628    pragma Pure_Function (To_Address);
 629
 630    function To_Address_Long_A is new
 631      Ada.Unchecked_Conversion (Unsigned_Longword, Address);
 632    pragma Pure_Function (To_Address_Long_A);
 633
 634    function To_Address_Long (X : Unsigned_Longword) return Address
 635      renames To_Address_Long_A;
 636    pragma Pure_Function (To_Address_Long);
 637
 638    function To_Integer_A is new
 639      Ada.Unchecked_Conversion (Address, Integer);
 640
 641    function To_Integer (X : Address) return Integer
 642      renames To_Integer_A;
 643
 644    function To_Unsigned_Longword_A is new
 645      Ada.Unchecked_Conversion (Address, Unsigned_Longword);
 646
 647    function To_Unsigned_Longword (X : Address) return Unsigned_Longword
 648      renames To_Unsigned_Longword_A;
 649
 650    function To_Unsigned_Longword_A is new
 651      Ada.Unchecked_Conversion (AST_Handler, Unsigned_Longword);
 652
 653    function To_Unsigned_Longword (X : AST_Handler) return Unsigned_Longword
 654      renames To_Unsigned_Longword_A;
 655
 656    pragma Warnings (On);
 657
 658 end System.Aux_DEC;