TARCAD: A template architecture for reconfigurable accelerator designs

In the race towards computational efficiency, accelerators are achieving prominence. Among the different types, accelerators built using reconfigurable fabric, such as FPGAs, have a tremendous potential due to the ability to customize the hardware to the application. However, the lack of a standard design methodology hinders the adoption of such devices and makes the portability and reusability across designs difficult. In addition, generation of highly customized circuits does not integrate nicely with high level synthesis tools. In this work, we introduce TARCAD, a template architecture to design reconfigurable accelerators. TARCAD enables high customization in the data management and compute engines while retaining a programming model based on generic programming principles. The template provides generality and scalable performance over a range of FPGAs. We describe the template architecture in detail and show how to implement five important scientific kernels: MxM, Acoustic Wave Equation, FFT, SpMV and Smith Waterman. TARCAD is compared with other High Level Synthesis models and is evaluated against GPUs, a well-known architecture that is far less customizable and, therefore, also easier to target from a simple and portable programming model. We analyze the TARCAD template and compare its efficiency on a large Xilinx Virtex-6 device to that of several recent GPU studies.