Abstract: The existing SLP algorithms cannot handle dependent ring and the reduction of the inner loop,and generate a large number of redundant packet disassembly and assignment statements in a basic block boundary,which leads to the lower quantization efficiency.In order to solve the problem,this paper proposed a SLP optimization algorithm using cross basic block transformation and loop distribution．Based on the control flow graph,according to the basic blocks of the array variable between Define-Use and across basic block data relation between across basic block,the algorithm makes the quantized transform,orderly uses across basic block transform and loop distribution,and then expands inner loop within a basic block sentence parallelism as far as possible,making SLP automatic vectorization compiler to generate the vectorization code which has more SIMD instruction．The experimental results show that the algorithm can hide more across basic block redundancy operation cost,at the same time generate better SIMD instructions across basic block data dependence,effectively improving the vectorization program speedup.

Key words: SLP,Cross basic block,Loop distribution,Data dependence,Control flow graph,Define-Use relationship