Mobile application processors are soon to replace desktop processors as the focus of innovation in microprocessor technology. Already, these processors have largely caught up to their more power hungry cousins, supporting out-of order execution and multicore processing. The natural evolution of mobile application processors is to use this dark silicon to create hundreds of automatically generated energy-saving cores, called conservation cores, which can reduce energy consumption by an order of magnitude. Conservation cores, or c-cores, are specialized processors that focus on reducing energy and energy-delay instead of increasing performance. This focus on energy makes c-cores an excellent match for many applications that would be poor candidates for hardware acceleration (e.g., irregular integer codes).This paper presents a toolchain for automatically synthesizing c-cores from application source code and demonstrates that they can significantly reduce energy for a wide range of applications. The c-cores support patching, a form of targeted reconfigurability, that allows them to adapt to new versions of the software they target. Conservation cores can reduce energy consumption by up to 16.0× for functions and by up to 2.1× for whole applications, while patching can extend the useful lifetime of individual ccores to match that of conventional processors.

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greendroid greendroid arcitecture CMOS scaling c- cores Dark silicon