The UNRAU a Unified Numeric Representation Arithmetic Unit

A companion paper entitled, "A Unified Numeric Data Type in Pascal", proposes the substitution of the standard data type real of the language Pascal with a unified data representation termed numeric. The numeric data type can represent a variety of arithmetic operands such as integers, normalized floating point numbers, and centered-radius intervals. This paper describes an arithmetic unit which is capable of executing the standard arithmetic operations (addition, subtraction, multiplication, and division) on pairs of operands specified to be of the numeric data type. This arithmetic unit, called the UNRAU — Unified Numeric Representation Arithmetic Unit, supports operations on operands externally represented as 5-tuples (t, a, e, f, r). The UNRAU provides for automatic conversion among the various data types and can also be used to perform an explicit conversion on a single operand. It is intended to implement the UNRAU on a dynamically microprogrammable microprocessor to determine what host facilities are required to efficiently realize such an arithmetic unit and to experiment with the high level language support of such a unit.