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+------------------------------------------------------------------------------
+-- --
+-- GNAT COMPILER COMPONENTS --
+-- --
+-- S Y S T E M . P O W T E N _ T A B L E --
+-- --
+-- S p e c --
+-- --
+-- Copyright (C) 1992-2009 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 provides a powers of ten table used for real conversions
+
+package System.Powten_Table is
+ pragma Pure;
+
+ Maxpow : constant := 22;
+ -- The number of entries in this table is chosen to include powers of ten
+ -- that are exactly representable with long_long_float. Assuming that on
+ -- all targets we have 53 bits of mantissa for the type, the upper bound is
+ -- given by 53/(log 5). If the scaling factor for a string is greater than
+ -- Maxpow, it can be obtained by several multiplications, which is less
+ -- efficient than with a bigger table, but avoids anomalies at end points.
+
+ Powten : constant array (0 .. Maxpow) of Long_Long_Float :=
+ (00 => 1.0E+00,
+ 01 => 1.0E+01,
+ 02 => 1.0E+02,
+ 03 => 1.0E+03,
+ 04 => 1.0E+04,
+ 05 => 1.0E+05,
+ 06 => 1.0E+06,
+ 07 => 1.0E+07,
+ 08 => 1.0E+08,
+ 09 => 1.0E+09,
+ 10 => 1.0E+10,
+ 11 => 1.0E+11,
+ 12 => 1.0E+12,
+ 13 => 1.0E+13,
+ 14 => 1.0E+14,
+ 15 => 1.0E+15,
+ 16 => 1.0E+16,
+ 17 => 1.0E+17,
+ 18 => 1.0E+18,
+ 19 => 1.0E+19,
+ 20 => 1.0E+20,
+ 21 => 1.0E+21,
+ 22 => 1.0E+22);
+
+end System.Powten_Table;