gcc/ada/s-unstyp.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                          GNAT RUN-TIME 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 --          Copyright (C) 1992-2009, 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 of standard unsigned types that
  33 --  correspond in size to the standard signed types declared in Standard,
  34 --  and (unlike the types in Interfaces) have corresponding names. It
  35 --  also contains some related definitions for other specialized types
  36 --  used by the compiler in connection with packed array types.
  37
  38 pragma Warnings (Off);
  39 pragma Compiler_Unit;
  40 pragma Warnings (On);
  41
  42 package System.Unsigned_Types is
  43    pragma Pure;
  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_Bytes array
  57
  58    type Packed_Bytes1 is array (Natural range <>) of Packed_Byte;
  59    for Packed_Bytes1'Alignment use 1;
  60    for Packed_Bytes1'Component_Size use Packed_Byte'Size;
  61    --  This is the type used to implement packed arrays where no alignment
  62    --  is required. This includes the cases of 1,2,4 (where we use direct
  63    --  masking operations), and all odd component sizes (where the clusters
  64    --  are not aligned anyway, see, e.g. System.Pack_07 in file s-pack07
  65    --  for details.
  66
  67    type Packed_Bytes2 is new Packed_Bytes1;
  68    for Packed_Bytes2'Alignment use Integer'Min (2, Standard'Maximum_Alignment);
  69    --  This is the type used to implement packed arrays where an alignment
  70    --  of 2 (is possible) is helpful for maximum efficiency of the get and
  71    --  set routines in the corresponding library unit. This is true of all
  72    --  component sizes that are even but not divisible by 4 (other than 2 for
  73    --  which we use direct masking operations). In such cases, the clusters
  74    --  can be assumed to be 2-byte aligned if the array is aligned. See for
  75    --  example System.Pack_10 in file s-pack10).
  76
  77    type Packed_Bytes4 is new Packed_Bytes1;
  78    for Packed_Bytes4'Alignment use Integer'Min (4, Standard'Maximum_Alignment);
  79    --  This is the type used to implement packed arrays where an alignment
  80    --  of 4 (if possible) is helpful for maximum efficiency of the get and
  81    --  set routines in the corresponding library unit. This is true of all
  82    --  component sizes that are divisible by 4 (other than powers of 2, which
  83    --  are either handled by direct masking or not packed at all). In such
  84    --  cases the clusters can be assumed to be 4-byte aligned if the array
  85    --  is aligned (see System.Pack_12 in file s-pack12 as an example).
  86
  87    type Bits_1 is mod 2**1;
  88    type Bits_2 is mod 2**2;
  89    type Bits_4 is mod 2**4;
  90    --  Types used for packed array conversions
  91
  92    subtype Bytes_F is Packed_Bytes4 (1 .. Float'Size / 8);
  93    --  Type used in implementation of Is_Negative intrinsic (see Exp_Intr)
  94
  95    function Shift_Left
  96      (Value  : Short_Short_Unsigned;
  97       Amount : Natural) return Short_Short_Unsigned;
  98
  99    function Shift_Right
 100      (Value  : Short_Short_Unsigned;
 101       Amount : Natural) return Short_Short_Unsigned;
 102
 103    function Shift_Right_Arithmetic
 104      (Value  : Short_Short_Unsigned;
 105       Amount : Natural) return Short_Short_Unsigned;
 106
 107    function Rotate_Left
 108      (Value  : Short_Short_Unsigned;
 109       Amount : Natural) return Short_Short_Unsigned;
 110
 111    function Rotate_Right
 112      (Value  : Short_Short_Unsigned;
 113       Amount : Natural) return Short_Short_Unsigned;
 114
 115    function Shift_Left
 116      (Value  : Short_Unsigned;
 117       Amount : Natural) return Short_Unsigned;
 118
 119    function Shift_Right
 120      (Value  : Short_Unsigned;
 121       Amount : Natural) return Short_Unsigned;
 122
 123    function Shift_Right_Arithmetic
 124      (Value  : Short_Unsigned;
 125       Amount : Natural) return Short_Unsigned;
 126
 127    function Rotate_Left
 128      (Value  : Short_Unsigned;
 129       Amount : Natural) return Short_Unsigned;
 130
 131    function Rotate_Right
 132      (Value  : Short_Unsigned;
 133       Amount : Natural) return Short_Unsigned;
 134
 135    function Shift_Left
 136      (Value  : Unsigned;
 137       Amount : Natural) return Unsigned;
 138
 139    function Shift_Right
 140      (Value  : Unsigned;
 141       Amount : Natural) return Unsigned;
 142
 143    function Shift_Right_Arithmetic
 144      (Value  : Unsigned;
 145       Amount : Natural) return Unsigned;
 146
 147    function Rotate_Left
 148      (Value  : Unsigned;
 149       Amount : Natural) return Unsigned;
 150
 151    function Rotate_Right
 152      (Value  : Unsigned;
 153       Amount : Natural) return Unsigned;
 154
 155    function Shift_Left
 156      (Value  : Long_Unsigned;
 157       Amount : Natural) return Long_Unsigned;
 158
 159    function Shift_Right
 160      (Value  : Long_Unsigned;
 161       Amount : Natural) return Long_Unsigned;
 162
 163    function Shift_Right_Arithmetic
 164      (Value  : Long_Unsigned;
 165       Amount : Natural) return Long_Unsigned;
 166
 167    function Rotate_Left
 168      (Value  : Long_Unsigned;
 169       Amount : Natural) return Long_Unsigned;
 170
 171    function Rotate_Right
 172      (Value  : Long_Unsigned;
 173       Amount : Natural) return Long_Unsigned;
 174
 175    function Shift_Left
 176      (Value  : Long_Long_Unsigned;
 177       Amount : Natural) return Long_Long_Unsigned;
 178
 179    function Shift_Right
 180      (Value  : Long_Long_Unsigned;
 181       Amount : Natural) return Long_Long_Unsigned;
 182
 183    function Shift_Right_Arithmetic
 184      (Value  : Long_Long_Unsigned;
 185       Amount : Natural) return Long_Long_Unsigned;
 186
 187    function Rotate_Left
 188      (Value  : Long_Long_Unsigned;
 189       Amount : Natural) return Long_Long_Unsigned;
 190
 191    function Rotate_Right
 192      (Value  : Long_Long_Unsigned;
 193       Amount : Natural) return Long_Long_Unsigned;
 194
 195    pragma Import (Intrinsic, Shift_Left);
 196    pragma Import (Intrinsic, Shift_Right);
 197    pragma Import (Intrinsic, Shift_Right_Arithmetic);
 198    pragma Import (Intrinsic, Rotate_Left);
 199    pragma Import (Intrinsic, Rotate_Right);
 200
 201    --  The following definitions are obsolescent. They were needed by the
 202    --  previous version of the compiler and runtime, but are not needed
 203    --  by the current version. We retain them to help with bootstrap path
 204    --  problems. Also they seem harmless, and if any user programs have
 205    --  been (rather improperly) using these types, why discombobulate them?
 206
 207    subtype Packed_Bytes           is Packed_Bytes4;
 208    subtype Packed_Bytes_Unaligned is Packed_Bytes1;
 209
 210 end System.Unsigned_Types;