OpenCL-Based FPGA-Platform for Stencil Computation and Its Optimization Methodology

Stencil computation is widely used in scientific computations and many accelerators based on multicore CPUs and GPUs have been proposed. Stencil computation has a small operational intensity so that a large external memory bandwidth is usually required for high performance. FPGAs have the potential to solve this problem by utilizing large internal memory efficiently. However, a very large design, testing and debugging time is required to implement an FPGA architecture successfully. To solve this problem, we propose an FPGA-platform using C-like programming language called open computing language (OpenCL). We also propose an optimization methodology to find the optimal architecture for a given application using the proposed FPFA-platform. According to the experimental results, we achieved 119 <inline-formula><tex-math notation="LaTeX">$\sim$</tex-math><alternatives> <inline-graphic xlink:href="waidyasooriya-ieq1-2614981.gif"/></alternatives></inline-formula> 237 Gflop/s of processing power and higher processing speed compared to conventional GPU and multicore CPU implementations.

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