Multipliers and Datapaths
Hesham Altwaijry, Michael J. Flynn · 1994
People traditionally have considered the number of counters in the critical path as the metric for the performance of a multiplier. This report presents the view that tree topologies which have the least number of levels do not always give the fastest possible multiplier when constrained to be part of a microprocessor. It proposes two new topologies: hybrid structure and higher order arrays which are faster than conventional tree topologies for typical datapaths. Key Words and Phrases: Floating-Point, Multiplication, Datapaths Copyright c fl 1994 by Hesham Al-Twaijry Michael Flynn Contents 1 Introduction 1 2 Background 2 3 Layout 3 4 Topology 5 5 Circuits 10 6 Simulation 10 7 Results 11 8 Conclusion 16 iii List of Figures 1 Multiplication Structures : : : : : : : : : : : : : : : : : : : : : : : : : : : : 1 2 IEEE Double Precision Format : : : : : : : : : : : : : : : : : : : : : : : : : 2 3 Datapath Structure : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 2 4 Mul...