Measuring the gap between programmable and fixed-function accelerators: A case study on speech recognition

As power and energy consumption have become the key design constraint of mobile systems, mobile system-on-chip (SoC) architects have dedicated a progressively larger area budget to custom accelerators: graphics processors, audio/video codecs, and image signal processors abound. Fixed-function accelerators now occupy more than half of the die area of these chips [2], and we foresee this trend only to progress in the near future.