-------------------------------------------------------------------------------- ---- GNAT COMPILER COMPONENTS ---- ---- S Y S T E M . A R I T H _ 6 4 ---- ---- S p e c ---- ---- $Revision: 1.7 $ ---- ---- Copyright (C) 1994,1995,1996 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, 59 Temple Place - Suite 330, Boston, ---- MA 02111-1307, 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. ---- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). ---- ---------------------------------------------------------------------------------- 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.withInterfaces;packageSystem.Arith_64ispragmaPure (Arith_64);subtypeInt64isInterfaces.Integer_64;functionAdd_With_Ovflo_Check (X, Y : Int64)returnInt64;-- Raises Constraint_Error if sum of operands overflows 64 bits,-- otherwise returns the 64-bit signed integer sum.functionSubtract_With_Ovflo_Check (X, Y : Int64)returnInt64;-- Raises Constraint_Error if difference of operands overflows 64-- bits, otherwise returns the 64-bit signed integer difference.functionMultiply_With_Ovflo_Check (X, Y : Int64)returnInt64;-- Raises Constraint_Error if product of operands overflows 64-- bits, otherwise returns the 64-bit signed integer difference.procedureScaled_Divide (X, Y, Z : Int64; Q, R :outInt64; 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.procedureDouble_Divide (X, Y, Z : Int64; Q, R :outInt64; 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.-- 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. The-- result is known to be in range except for the noted possibility of-- Y or Z being zero, so no other overflow checks are required.endSystem.Arith_64;