gcc/ada/s-carun8.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                    GNAT RUN-TIME LIBRARY COMPONENTS                      --
   4 --                                                                          --
   5 --       S Y S T E M . C O M P A R E _ A R R A Y _ U N S I G N E D _ 8      --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 2002-2008, 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 --  This package contains functions for runtime comparisons on arrays whose
  35 --  elements are 8-bit discrete type values to be treated as unsigned.
  36
  37 pragma Warnings (Off);
  38 pragma Compiler_Unit;
  39 pragma Warnings (On);
  40
  41 package System.Compare_Array_Unsigned_8 is
  42
  43    --  Note: although the functions in this package are in a sense Pure, the
  44    --  package cannot be declared as Pure, since the arguments are addresses,
  45    --  not the data, and the result is not pure wrt the address values.
  46
  47    function Compare_Array_U8
  48      (Left      : System.Address;
  49       Right     : System.Address;
  50       Left_Len  : Natural;
  51       Right_Len : Natural) return Integer;
  52    --  Compare the array starting at address Left of length Left_Len with the
  53    --  array starting at address Right of length Right_Len. The comparison is
  54    --  in the normal Ada semantic sense of array comparison. The result is -1,
  55    --  0, +1 for Left < Right, Left = Right, Left > Right respectively. This
  56    --  function works with 4 byte words if the operands are aligned on 4-byte
  57    --  boundaries and long enough.
  58
  59    function Compare_Array_U8_Unaligned
  60      (Left      : System.Address;
  61       Right     : System.Address;
  62       Left_Len  : Natural;
  63       Right_Len : Natural) return Integer;
  64    --  Same functionality as Compare_Array_U8 but always proceeds by bytes.
  65    --  Used when the caller knows that the operands are unaligned, or short
  66    --  enough that it makes no sense to go by words.
  67
  68 end System.Compare_Array_Unsigned_8;