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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . E X P I N T --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2025, 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 --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package implements Integer exponentiation (checks on)
-- Preconditions, postconditions, ghost code, loop invariants and assertions
-- in this unit are meant for analysis only, not for run-time checking, as it
-- would be too costly otherwise. This is enforced by setting the assertion
-- policy to Ignore.
pragma Assertion_Policy (Pre => Ignore,
Post => Ignore,
Ghost => Ignore,
Loop_Invariant => Ignore,
Assert => Ignore);
with System.Expont;
package System.Exp_Int
with SPARK_Mode
is
package Expont_Integer is new Expont (Integer);
function Exp_Integer (Left : Integer; Right : Natural) return Integer
renames Expont_Integer.Expon;
-- Return the power of ``Left`` by ``Right`` where ``Left`` is an
-- Integer.
--
-- This function is implemented using the standard logarithmic approach:
-- ``Right`` gets shifted right testing successive low order bits, and
-- ``Left`` is raised to the next power of 2.
--
-- In case of overflow, Constraint_Error is raised.
end System.Exp_Int;
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