METHOD AND APPARATUS FOR ARITHMETIC OPERATION

摘要

An arithmetic operation apparatus for determining a cumulative sum of products, which produces a result from a plurality of separate input data items without carrying out any transfer or addition of data so that a smaller number of operation cycles may be required. Input data X and Y are processed through a first decoder (511), a first selector (521), a first partial product generator (531) and first full adder (541) in order to provide the product of higher bits of the data X and Y. The input data X and Y are also processed through a second decoder (512), a second selector (522), a second partial product generator (532) and second full adder (542) in order to provide the product of lower bits of the data X and Y. The results are supplied to a shifter (55) for an adjustment of the number of shifts. The output from the shifter is processed through a third full adder (56) and a carry propagation adder (58) to provide a cumulative sum of products, or data Z, which is fed back to the input of the third full adder (56).