gcc/ada/s-unstyp.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                          GNAT RUNTIME COMPONENTS                         --
   4 --                                                                          --
   5 --                S Y S T E M . U N S I G N E D _ T Y P E S                 --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                            $Revision: 1.20 $
  10 --                                                                          --
  11 --          Copyright (C) 1992-2001 Free Software Foundation, Inc.          --
  12 --                                                                          --
  13 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  14 -- terms of the  GNU General Public License as published  by the Free Soft- --
  15 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  16 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  17 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  18 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  19 -- for  more details.  You should have  received  a copy of the GNU General --
  20 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  21 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  22 -- MA 02111-1307, USA.                                                      --
  23 --                                                                          --
  24 -- As a special exception,  if other files  instantiate  generics from this --
  25 -- unit, or you link  this unit with other files  to produce an executable, --
  26 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  27 -- covered  by the  GNU  General  Public  License.  This exception does not --
  28 -- however invalidate  any other reasons why  the executable file  might be --
  29 -- covered by the  GNU Public License.                                      --
  30 --                                                                          --
  31 -- GNAT was originally developed  by the GNAT team at  New York University. --
  32 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
  33 --                                                                          --
  34 ------------------------------------------------------------------------------
  35
  36 --  This package contains definitions of standard unsigned types that
  37 --  correspond in size to the standard signed types declared in Standard.
  38 --  and (unlike the types in Interfaces have corresponding names). It
  39 --  also contains some related definitions for other specialized types
  40 --  used only by the expander.
  41
  42 package System.Unsigned_Types is
  43 pragma Pure (Unsigned_Types);
  44
  45    type Short_Short_Unsigned is mod 2 ** Short_Short_Integer'Size;
  46    type Short_Unsigned       is mod 2 ** Short_Integer'Size;
  47    type Unsigned             is mod 2 ** Integer'Size;
  48    type Long_Unsigned        is mod 2 ** Long_Integer'Size;
  49    type Long_Long_Unsigned   is mod 2 ** Long_Long_Integer'Size;
  50
  51    type Float_Unsigned       is mod 2 ** Float'Size;
  52    --  Used in the implementation of Is_Negative intrinsic (see Exp_Intr)
  53
  54    type Packed_Byte is mod 2 ** 8;
  55    for Packed_Byte'Size use 8;
  56    --  Component type for Packed_Butes array
  57
  58    type Packed_Bytes1 is array (Natural range <>) of Packed_Byte;
  59    for Packed_Bytes1'Alignment use 1;
  60    --  This is the type used to implement packed arrays where no alignment
  61    --  is required. This includes the cases of 1,2,4 (where we use direct
  62    --  masking operations), and all odd component sizes (where the clusters
  63    --  are not aligned anyway, see, e.g. System.Pack_07 in file s-pack07
  64    --  for details.
  65
  66    type Packed_Bytes2 is new Packed_Bytes1;
  67    for Packed_Bytes2'Alignment use 2;
  68    --  This is the type used to implement packed arrays where an alignment
  69    --  of 2 is helpful for maximum efficiency of the get and set routines
  70    --  in the corresponding library unit. This is true of all component
  71    --  sizes that are even but not divisible by 4 (other than 2 for which
  72    --  we use direct masking operations). In such cases, the clusters can
  73    --  be assumed to be 2-byte aligned if the array is aligned. See for
  74    --  example System.Pack_10 in file s-pack10).
  75
  76    type Packed_Bytes4 is new Packed_Bytes1;
  77    for Packed_Bytes4'Alignment use Integer'Min (4, Standard'Maximum_Alignment);
  78    --  This is the type used to implement packed arrays where an alignment
  79    --  of 4 is helpful for maximum efficiency of the get and set routines
  80    --  in the corresponding library unit. This is true of all component
  81    --  sizes that are divisible by 4 (other than powers of 2, which are
  82    --  either handled by direct masking or not packed at all). In such cases
  83    --  the clusters can be assumed to be 4-byte aligned if the array is
  84    --  aligned (see System.Pack_12 in file s-pack12 as an example).
  85
  86    type Bits_1 is mod 2**1;
  87    type Bits_2 is mod 2**2;
  88    type Bits_4 is mod 2**4;
  89    --  Types used for packed array conversions
  90
  91    subtype Bytes_F is Packed_Bytes4 (1 .. Float'Size / 8);
  92    --  Type used in implementation of Is_Negative instrinsic (see Exp_Intr)
  93
  94    function Shift_Left
  95      (Value  : Short_Short_Unsigned;
  96       Amount : Natural)
  97       return   Short_Short_Unsigned;
  98
  99    function Shift_Right
 100      (Value  : Short_Short_Unsigned;
 101       Amount : Natural)
 102       return   Short_Short_Unsigned;
 103
 104    function Shift_Right_Arithmetic
 105      (Value  : Short_Short_Unsigned;
 106       Amount : Natural)
 107       return   Short_Short_Unsigned;
 108
 109    function Rotate_Left
 110      (Value  : Short_Short_Unsigned;
 111       Amount : Natural)
 112       return   Short_Short_Unsigned;
 113
 114    function Rotate_Right
 115      (Value  : Short_Short_Unsigned;
 116       Amount : Natural)
 117       return   Short_Short_Unsigned;
 118
 119    function Shift_Left
 120      (Value  : Short_Unsigned;
 121       Amount : Natural)
 122       return   Short_Unsigned;
 123
 124    function Shift_Right
 125      (Value  : Short_Unsigned;
 126       Amount : Natural)
 127       return   Short_Unsigned;
 128
 129    function Shift_Right_Arithmetic
 130      (Value  : Short_Unsigned;
 131       Amount : Natural)
 132       return   Short_Unsigned;
 133
 134    function Rotate_Left
 135      (Value  : Short_Unsigned;
 136       Amount : Natural)
 137       return   Short_Unsigned;
 138
 139    function Rotate_Right
 140      (Value  : Short_Unsigned;
 141       Amount : Natural)
 142       return   Short_Unsigned;
 143
 144    function Shift_Left
 145      (Value  : Unsigned;
 146       Amount : Natural)
 147      return    Unsigned;
 148
 149    function Shift_Right
 150      (Value  : Unsigned;
 151       Amount : Natural)
 152       return   Unsigned;
 153
 154    function Shift_Right_Arithmetic
 155      (Value  : Unsigned;
 156       Amount : Natural)
 157       return   Unsigned;
 158
 159    function Rotate_Left
 160      (Value  : Unsigned;
 161       Amount : Natural)
 162       return   Unsigned;
 163
 164    function Rotate_Right
 165      (Value  : Unsigned;
 166       Amount : Natural)
 167       return   Unsigned;
 168
 169    function Shift_Left
 170      (Value  : Long_Unsigned;
 171       Amount : Natural)
 172      return    Long_Unsigned;
 173
 174    function Shift_Right
 175      (Value  : Long_Unsigned;
 176       Amount : Natural)
 177       return   Long_Unsigned;
 178
 179    function Shift_Right_Arithmetic
 180      (Value  : Long_Unsigned;
 181       Amount : Natural)
 182       return   Long_Unsigned;
 183
 184    function Rotate_Left
 185      (Value  : Long_Unsigned;
 186       Amount : Natural)
 187       return   Long_Unsigned;
 188
 189    function Rotate_Right
 190      (Value  : Long_Unsigned;
 191       Amount : Natural)
 192       return   Long_Unsigned;
 193
 194    function Shift_Left
 195      (Value  : Long_Long_Unsigned;
 196       Amount : Natural)
 197      return    Long_Long_Unsigned;
 198
 199    function Shift_Right
 200      (Value  : Long_Long_Unsigned;
 201       Amount : Natural)
 202       return   Long_Long_Unsigned;
 203
 204    function Shift_Right_Arithmetic
 205      (Value  : Long_Long_Unsigned;
 206       Amount : Natural)
 207       return   Long_Long_Unsigned;
 208
 209    function Rotate_Left
 210      (Value  : Long_Long_Unsigned;
 211       Amount : Natural)
 212       return   Long_Long_Unsigned;
 213
 214    function Rotate_Right
 215      (Value  : Long_Long_Unsigned;
 216       Amount : Natural)
 217       return   Long_Long_Unsigned;
 218
 219    pragma Import (Intrinsic, Shift_Left);
 220    pragma Import (Intrinsic, Shift_Right);
 221    pragma Import (Intrinsic, Shift_Right_Arithmetic);
 222    pragma Import (Intrinsic, Rotate_Left);
 223    pragma Import (Intrinsic, Rotate_Right);
 224
 225    --  The following definitions are obsolsecent. They were needed by the
 226    --  previous version of the compiler and runtime, but are not needed
 227    --  by the current version. We retain them to help with bootstrap path
 228    --  problems. Also they seem harmless, and if any user programs have
 229    --  been (rather improperly) using these types, why discombobulate them?
 230
 231    subtype Packed_Bytes           is Packed_Bytes4;
 232    subtype Packed_Bytes_Unaligned is Packed_Bytes1;
 233
 234 end System.Unsigned_Types;