gcc/ada/s-stoele.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --               S Y S T E M . S T O R A G E _ E L E M E N T S              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2004 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 2,  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 COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 with Unchecked_Conversion;
  35 package body System.Storage_Elements is
  36
  37    pragma Suppress (All_Checks);
  38
  39    function To_Address is new Unchecked_Conversion (Storage_Offset, Address);
  40    function To_Offset  is new Unchecked_Conversion (Address, Storage_Offset);
  41
  42    --  Address arithmetic
  43
  44    function "+" (Left : Address; Right : Storage_Offset) return Address is
  45    begin
  46       return To_Address (To_Integer (Left) + To_Integer (To_Address (Right)));
  47    end "+";
  48
  49    function "+" (Left : Storage_Offset; Right : Address) return Address is
  50    begin
  51       return To_Address (To_Integer (To_Address (Left)) + To_Integer (Right));
  52    end "+";
  53
  54    function "-" (Left : Address; Right : Storage_Offset) return Address is
  55    begin
  56       return To_Address (To_Integer (Left) - To_Integer (To_Address (Right)));
  57    end "-";
  58
  59    function "-" (Left, Right : Address) return Storage_Offset is
  60    begin
  61       return To_Offset (To_Address (To_Integer (Left) - To_Integer (Right)));
  62    end "-";
  63
  64    function "mod" (Left : Address; Right : Storage_Offset)
  65      return Storage_Offset is
  66    begin
  67       if Right >= 0 then
  68          return Storage_Offset
  69                   (To_Integer (Left) mod Integer_Address (Right));
  70       else
  71          return -Storage_Offset
  72                   (To_Integer (Left) mod Integer_Address (-Right));
  73       end if;
  74    end "mod";
  75
  76    --  Conversion to/from integers
  77
  78    function To_Address (Value : Integer_Address) return Address is
  79    begin
  80       return Address (Value);
  81    end To_Address;
  82
  83    function To_Integer (Value : Address) return Integer_Address is
  84    begin
  85       return Integer_Address (Value);
  86    end To_Integer;
  87
  88 end System.Storage_Elements;