A power reduction technique with object code merging for application specific embedded processors

In this paper, a power reduction technique which merges frequently executed sequences of object codes into a set of single instructions is proposed. The merged sequence of object codes is restored by an instruction decompressor before decoding the object codes. The decompressor is implemented by a ROM. In many programs, only a few sequences of object codes are frequently executed. Therefore, merging these frequently executed sequences into a single instruction leads to a significant energy reduction. Our experiments with actual read only memory (ROM) modules and some benchmark program demonstrate significant energy reductions up to more than 65% at best case over an instruction memory without the object code merging.

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