关键词: 非正规化循环, 单指令多数据向量化, 展开压紧, 依赖关系分析

Abstract: Concerning that the upper, lower bounds and stride of the non-normalized loop are uncertain, some issues were normalized based on a transform method such as that loop conditions were logical expression, increment-reduction statement and do-while. An unroll-jam method was proposed to deal with the loops that cannot be normalized, which mined the unroll-jam results by Superword Level Parellelism (SLP) vectorization. Compared with the existing Single Instruction Multiple Data (SIMD) vectorization method for non-normalized loops, the experimental results show that the transform method and unroll-jam method are better to explore the parallelism of the non-normalized loops, which can improve the performance by more than 6%.

Key words: non-noramlized loop, Single Instruction Multiple Data (SIMD) vectorization, unroll and jam, data dependence analysis