Generalized Fractured Integer Multiplier Based on Divide and Conquer with Tree Pruning

Abstract

Data parallel applications frequently work with data elements whose width is less than the processor dathpath width. However, most processors do not support parallelism of multiple sub-width elements but rather expand them to the datapath width and process them in a sequential manner. In this paper, we propose a set of systematic divide and conquer approaches to design a fractured integer multiplier unit which allows for either a single datapath-width multiplication or multiple sub-width multiplications to be simultaneously executed. The supported integer width can be configured at runtime. We also evaluate and compare the proposed approaches demonstrating the advantages and disadvantages of each. Such fractured multipliers are particularly suitable for vector and multimedia processors.