An area-effective datapath architecture for embedded microprocessors and scalable systems

We have proposed area-reduction techniques for superscalar datapath architectures with 34 SIMD instructions and have developed an integer-media unit based on these techniques. The unit's design is both functionally asymmetrical and integer-SIMD unified, and the resulting savings in area are 27%-48% as compared to other, functionally equivalent mid-level microprocessor designs, with performance that is, at most, only 7.2% lower. Further, in 2-D IDCT processing, the unit outperforms embedded microprocessor designs without SIMD functions by 49%-118%. Specifically, effective area reduction of adders, shifters, and multiply-and-adders has been achieved by using the unified design. These area-effective techniques are useful for embedded microprocessors and scalable systems that employ highly parallel superscalar and on-chip parallel architectures. The integer-media unit has been implemented in an evaluation chip fabricated with 0.15-μm 5-metal CMOS technology.