A Parallelism Strategy Optimization Search Algorithm Based on Three-dimensional Deformable CNN Acceleration Architecture

Field Programmable Gate Array (FPGA) is widely used in Convolutional Neural Network (CNN) hardware acceleration. For better performance, a three-dimensional transformable CNN acceleration structure is proposed by Qu et al (2021). However, this structure brings an explosive growth of the parallelism strategy exploration space, thus the time cost to search the optimal parallelism has surged, which reduces severely the feasibility of accelerator implementation. To solve this issue, a fine-grained iterative optimization parallelism search algorithm is proposed in this paper. The algorithm uses multiple rounds of iterative data filtering to eliminate efficiently the redundant parallelism schemes, compressing more than 99% of the search space. At the same time, the algorithm uses pruning operation to delete invalid calculation branches, and reduces successfully the calculation time from 10(6) h to less than 10 s. The algorithm can achieve outstanding performance in different kinds of FPGAs, with an average computing resource utilization (R1, R2) up to (0.957, 0.962).