------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S Y S T E M . A R I T H _ 6 4 -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2005, 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 2, 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. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- -- Boston, MA 02110-1301, USA. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- This unit provides software routines for doing arithmetic on 64-bit -- signed integer values in cases where either overflow checking is -- required, or intermediate results are longer than 64 bits. with Interfaces; package System.Arith_64 is pragma Pure; subtype Int64 is Interfaces.Integer_64; function Add_With_Ovflo_Check (X, Y : Int64) return Int64; -- Raises Constraint_Error if sum of operands overflows 64 bits, -- otherwise returns the 64-bit signed integer sum. function Subtract_With_Ovflo_Check (X, Y : Int64) return Int64; -- Raises Constraint_Error if difference of operands overflows 64 -- bits, otherwise returns the 64-bit signed integer difference. function Multiply_With_Ovflo_Check (X, Y : Int64) return Int64; -- Raises Constraint_Error if product of operands overflows 64 -- bits, otherwise returns the 64-bit signed integer product. procedure Scaled_Divide (X, Y, Z : Int64; Q, R : out Int64; Round : Boolean); -- Performs the division of (X * Y) / Z, storing the quotient in Q -- and the remainder in R. Constraint_Error is raised if Z is zero, -- or if the quotient does not fit in 64-bits. Round indicates if -- the result should be rounded. If Round is False, then Q, R are -- the normal quotient and remainder from a truncating division. -- If Round is True, then Q is the rounded quotient. the remainder -- R is not affected by the setting of the Round flag. procedure Double_Divide (X, Y, Z : Int64; Q, R : out Int64; Round : Boolean); -- Performs the division X / (Y * Z), storing the quotient in Q and -- the remainder in R. Constraint_Error is raised if Y or Z is zero, -- or if the quotient does not fit in 64-bits. Round indicates if the -- result should be rounded. If Round is False, then Q, R are the normal -- quotient and remainder from a truncating division. If Round is True, -- then Q is the rounded quotient. The remainder R is not affected by the -- setting of the Round flag. end System.Arith_64;