------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- S Y S T E M . E X P O N T -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2022, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- Signed integer exponentiation (checks on) with Ada.Numerics.Big_Numbers.Big_Integers_Ghost; generic type Int is range <>; package System.Expont with Pure, SPARK_Mode is -- Preconditions in this unit are meant for analysis only, not for run-time -- checking, so that the expected exceptions are raised. This is enforced -- by setting the corresponding assertion policy to Ignore. Postconditions -- and contract cases should not be executed at runtime as well, in order -- not to slow down the execution of these functions. pragma Assertion_Policy (Pre => Ignore, Post => Ignore, Contract_Cases => Ignore, Ghost => Ignore); package BI_Ghost renames Ada.Numerics.Big_Numbers.Big_Integers_Ghost; subtype Big_Integer is BI_Ghost.Big_Integer with Ghost; use type BI_Ghost.Big_Integer; package Signed_Conversion is new BI_Ghost.Signed_Conversions (Int => Int); function Big (Arg : Int) return Big_Integer is (Signed_Conversion.To_Big_Integer (Arg)) with Ghost; function In_Int_Range (Arg : Big_Integer) return Boolean is (BI_Ghost.In_Range (Arg, Big (Int'First), Big (Int'Last))) with Ghost; function Expon (Left : Int; Right : Natural) return Int with Pre => In_Int_Range (Big (Left) ** Right), Post => Expon'Result = Left ** Right; end System.Expont;