A reconfigurable multifunction computing cache architecture

A considerable portion of a microprocessor chip is dedicated to cache memory. However, not all applications need all the cache storage all the time, especially the computing bandwidth-limited applications. In addition, some applications have large embedded computations with a regular structure. Such applications may be able to use additional computing resources. If the unused portion of the cache could serve these computation needs, the on-chip resources would be utilized more efficiently. This presents an opportunity to explore the reconfiguration of a part of the cache memory for computing. Thus, we propose adaptive balanced computing (ABC)-dynamic resource configuration on demand from application-between memory and computing resources. In this paper, we present a cache architecture to convert a cache into a computing unit for either of the following two structured computations: finite impulse response and discrete/inverse discrete cosine transform. In order to convert a cache memory to a function unit, we include additional logic to embed multibit output lookup tables into the cache structure. The experimental results show that the reconfigurable module improves the execution time of applications with a large number of data elements by a factor as high as 50 and 60.