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The logarithmic number system (LNS) has found appeal in digital arithmetic because it allows multiplication and division to be performed much faster and more accurately than with widely-used floating-point (FP) number formats. We present a comprehensive review and comparison of various techniques and architectures for performing arithmetic operations efficiently in LNS, using the sign/logarithm format, and focus on the European Logarithmic Microprocessor (ELM), a device built in the framework of a research project launched in 1999, as an important case study. Comparison of the arithmetic performance of ELM with that of a commercial superscalar pipelined FP processor of the same vintage and technology confirms that LNS has the potential for successful deployment in general-purpose systems. Besides paying due attention to LNS attributes beyond computational speed and accuracy, novel contributions of this survey include an exploration of the relationship of LNS with the emerging field of approximate computing and a discussion of the discrete logarithmic number system. [ABSTRACT FROM AUTHOR]

Today's computing is increasingly data-intensive, heralding the age of big data. With greater data volumes, come the needs for faster processing, greater storage capacity, and expanded communication bandwidth, all of which imply the expenditure of more energy. Thus, energy efficiency, already a major design consideration, will assume broader significance in the coming years. As important as storage and communications are, our focus in this paper is on better technology to reduce the computation (logic manipulation) power. We review majority logic, a special case of threshold logic, show how a number of common arithmetic/logic operations can be performed using the majority-gate primitive, and review an impressive array of atomic-scale logic technologies that are particularly efficient in realizing the majority or minority function. We conclude that a combination of orders of magnitude energy reduction by virtue of the technology used and implementation strategies that lead to comparable complexity in terms of majority gates when contrasted with currently used circuit primitives (AND, OR, XOR, NOT, mux) leads to energy-efficient realization of arithmetic/logic functions suitable for use in the age of big data. [ABSTRACT FROM AUTHOR]