1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S Y S T E M . B I G N U M S -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 2012-2019, 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 package provides arbitrary precision signed integer arithmetic for 33-- use in computing intermediate values in expressions for the case where 34-- pragma Overflow_Check (Eliminated) is in effect. 35 36-- Note that we cannot use a straight instantiation of System.Generic_Bignums 37-- because the rtsfind mechanism is not ready to handle instantiations. 38 39package System.Bignums is 40 pragma Preelaborate; 41 42 type Bignum is private; 43 44 function Big_Add (X, Y : Bignum) return Bignum; -- "+" 45 function Big_Sub (X, Y : Bignum) return Bignum; -- "-" 46 function Big_Mul (X, Y : Bignum) return Bignum; -- "*" 47 function Big_Div (X, Y : Bignum) return Bignum; -- "/" 48 function Big_Exp (X, Y : Bignum) return Bignum; -- "**" 49 function Big_Mod (X, Y : Bignum) return Bignum; -- "mod" 50 function Big_Rem (X, Y : Bignum) return Bignum; -- "rem" 51 function Big_Neg (X : Bignum) return Bignum; -- "-" 52 function Big_Abs (X : Bignum) return Bignum; -- "abs" 53 -- Perform indicated arithmetic operation on bignum values. No exception 54 -- raised except for Div/Mod/Rem by 0 which raises Constraint_Error with 55 -- an appropriate message. 56 57 function Big_EQ (X, Y : Bignum) return Boolean; -- "=" 58 function Big_NE (X, Y : Bignum) return Boolean; -- "/=" 59 function Big_GE (X, Y : Bignum) return Boolean; -- ">=" 60 function Big_LE (X, Y : Bignum) return Boolean; -- "<=" 61 function Big_GT (X, Y : Bignum) return Boolean; -- ">" 62 function Big_LT (X, Y : Bignum) return Boolean; -- "<" 63 -- Perform indicated comparison on bignums, returning result as Boolean. 64 -- No exception raised for any input arguments. 65 66 function Bignum_In_LLI_Range (X : Bignum) return Boolean; 67 -- Returns True if the Bignum value is in the range of Long_Long_Integer, 68 -- so that a call to From_Bignum is guaranteed not to raise an exception. 69 70 function To_Bignum (X : Long_Long_Integer) return Bignum; 71 -- Convert Long_Long_Integer to Bignum. No exception can be raised for any 72 -- input argument. 73 74 function From_Bignum (X : Bignum) return Long_Long_Integer; 75 -- Convert Bignum to Long_Long_Integer. Constraint_Error raised with 76 -- appropriate message if value is out of range of Long_Long_Integer. 77 78private 79 80 type Bignum is new System.Address; 81 82 pragma Inline (Big_Add); 83 pragma Inline (Big_Sub); 84 pragma Inline (Big_Mul); 85 pragma Inline (Big_Div); 86 pragma Inline (Big_Exp); 87 pragma Inline (Big_Mod); 88 pragma Inline (Big_Rem); 89 pragma Inline (Big_Neg); 90 pragma Inline (Big_Abs); 91 pragma Inline (Big_EQ); 92 pragma Inline (Big_NE); 93 pragma Inline (Big_GE); 94 pragma Inline (Big_LE); 95 pragma Inline (Big_GT); 96 pragma Inline (Big_LT); 97 pragma Inline (Bignum_In_LLI_Range); 98 pragma Inline (To_Bignum); 99 pragma Inline (From_Bignum); 100 101end System.Bignums; 102