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- -------- SIMTEL20 Ada Software Repository Prologue ------------
- -- -*
- -- Unit name : Emulation of Machine Arithmetic
- -- Version : 1.0
- -- Author : SYSCON Corp
- -- : 3990 Sherman Street
- -- : San Diego, CA 92110
- -- : John Reddan
- -- : (619) 296-0085
- -- : Contact: Lt. Colonel Falgiano
- -- : ESD/SCW
- -- : Hanscom AFB, MA 01731
- -- DDN Address :
- -- Copyright : (c) 1985, SYSCON Corp
- -- Date created : June, 1985
- -- Release date : June, 1985
- -- Last update : June, 1985
- -- Machine/System Compiled/Run on : VAX/VMS TeleSoft
- -- -*
- ---------------------------------------------------------------
- -- -*
- -- Keywords :
- ----------------:
- --
- -- Abstract :
- ----------------: The purpose of this package is to emulate
- ----------------: 36 bit machine host arithmetic on a 32
- ----------------: bit host machine. This package will provide
- ----------------: support for 36 bit integer, real, and double
- ----------------: precision real numbers in the form of the
- ----------------: standard predefined arithmetic operations.
- ----------------: The ranges of the supported types are as
- ----------------: follows:
- ----------------:
- ----------------: Integer
- ----------------: range of -2**35 to 2**35-1
- ----------------: Real
- ----------------: range of 10**-38 to 10**38 and 0
- ----------------: mantissa => 27 bit binary fraction
- ----------------: exponent => -128 to 127
- ----------------: Double Precision Real
- ----------------: range of 10**-38 to 10**38 and 0
- ----------------: mantissa => 63 bit binary fraction
- ----------------: exponent => -128 to 127
- ----------------:
- ----------------: Any errors which occur during use of the arithmetic
- ----------------: exception declaration in the package specification can
- ----------------: be changed to a rename of the predefined exception
- ----------------: "NUMERIC_ERROR" for programs needing to handle
- ----------------: arithmetic errors in a general fashion.
- ----------------: Conversion functions are provided to assist in
- ----------------: programming mixed operand (32 and 36 bit)
- ----------------: arithmetic, and to facilitate IO. These functions
- ----------------: should be renamed if they will be used extensively so
- ----------------: that the impact of the readability of a program's
- ----------------: arithmetic expressions is minimized. The underlying
- ----------------: arithmetic will be performed in twos complement
- ----------------: arithmetic.
- ----------------:
- ----------------: This tool was developed as a precursor for
- ----------------: the WWMCCS Information System (WIS). An
- ----------------: executable version of the tool has been
- ----------------: demonstrated.
- ----------------:
- -- -*
- ------------------ Revision history ---------------------------
- -- -*
- -- DATE VERSION AUTHOR HISTORY
- -- 6/85 1.0 SYSCON Initial Release
- -- -*
- ------------------ Distribution and Copyright -----------------
- -- -*
- -- This prologue must be included in all copies of this software.
- --
- -- This software is copyright by the author.
- --
- -- This software is released to the Ada community.
- -- This software is released to the Public Domain (note:
- -- software released to the Public Domain is not subject
- -- to copyright protection).
- -- Restrictions on use or distribution: NONE
- -- -*
- ----------------- Disclaimer ----------------------------------
- -- -*
- -- This software and its documentation are provided "AS IS" and
- -- without any expressed or implied warranties whatsoever.
- --
- -- No warranties as to performance, merchantability, or fitness
- -- for a particular purpose exist.
- --
- -- Because of the diversity of conditions and hardware under
- -- which this software may be used, no warranty of fitness for
- -- a particular purpose is offered. The user is advised to
- -- test the software thoroughly before relying on it. The user
- -- must assume the entire risk and liability of using this
- -- software.
- --
- -- In no event shall any person or organization of people be
- -- held responsible for any direct, indirect, consequential
- -- or inconsequential damages or lost profits.
- -- -*
- ----------------- END-PROLOGUE -------------------------------
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