MULTIPLYING UNIT IN A COMPUTER SYSTEM, CAPABLE OF POPULATION COUNTING

摘要

Population counting in a computer system is performed by using a multiplying unit in the computer system. The multiplying unit includes several multiplying sub-units for simultaneously executing partial multiplication among elements obtained by dividing a multiplicand data and a multiplier data in a regular multiplication mode. In a population counting mode, an input data for the population counting is divided into population counting elements instead of the multiplier data. Population countings for the elements are performed simultaneously by using the multiplying sub-units, producing partial counted data of the population counting elements, and the partial counted data are sent to a pair of carry save and carry propagate adders by which a population counting result for the input data is obtained and output.