gcc/ada/libgnat/s-explllu.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                      S Y S T E M . E X P _ L L L U                       --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2024, 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 function performs exponentiation of unsigned types with binary modulus
  33 --  values exceeding that of System.Unsigned_Types.Long_Long_Unsigned.
  34 --  The result is always full width, the caller must do a masking operation if
  35 --  the modulus is less than 2 ** Long_Long_Long_Unsigned'Size.
  36
  37 --  Preconditions in this unit are meant for analysis only, not for run-time
  38 --  checking, so that the expected exceptions are raised. This is enforced
  39 --  by setting the corresponding assertion policy to Ignore. Postconditions
  40 --  and contract cases should not be executed at runtime as well, in order
  41 --  not to slow down the execution of these functions.
  42
  43 pragma Assertion_Policy (Pre            => Ignore,
  44                          Post           => Ignore,
  45                          Contract_Cases => Ignore,
  46                          Ghost          => Ignore);
  47
  48 with System.Exponu;
  49 with System.Unsigned_Types;
  50
  51 package System.Exp_LLLU
  52   with SPARK_Mode
  53 is
  54
  55    subtype Long_Long_Long_Unsigned is Unsigned_Types.Long_Long_Long_Unsigned;
  56
  57    function Exp_Long_Long_Long_Unsigned is
  58      new Exponu (Long_Long_Long_Unsigned);
  59    pragma Pure_Function (Exp_Long_Long_Long_Unsigned);
  60
  61 end System.Exp_LLLU;