A superscalar RISC processor with pseudo vector processing feature

A novel architectural extension, in which floating-point data are transferred directly from main memory to floating-point registers, has been successfully implemented in a superscalar RISC processor. This extension allows main memory access throughput of 1.2 Gbyte/s, and effective performance reaches 267 MFLOPS (89% of the peak performance) for typical floating-point applications. The processor utilizes 0.3-micron 4-level metal CMOS technology with 2.5 V power supply and contains 3.9 million transistors in 15.7 mm/spl times/15.7 mm die size. Only 4.5% of the die area is used for the extension. Pipeline stage optimization and scoreboard-based dependency check method allow the extension to be realized without affecting the operating frequency.