A C-to-RTL Flow as an Energy Efficient Alternative to Embedded Processors in Digital Systems

We present a high-level synthesis flow for mapping an algorithm description (in C) to a provably equivalent register transfer level (RTL) description of hardware. This flow uses an intermediate representation which is an orthogonal factorization of the program behavior into control, data and memory aspects, and is suitable for the description of large systems. We show that optimizations such as arbiter-less resource sharing can be efficiently computed on this representation. We apply the flow to a wide range of examples ranging from stream ciphers to database and linear algebra applications. The resulting RTL is then put through a standard ASIC tool chain (synthesis followed by automatic place-and-route), and the performance and power dissipation of the resulting layout is computed. We observe that the energy consumption (per completed task) of each resulting circuit is considerably lower than that of an equivalent executable running on a low-power processor, indicating that this C-to-RTL flow offers an energy efficient alternative to the use of embedded processors in mapping algorithms to digital VLSI systems.