关键词: 无效代码删除, 编译优化, 数据流分析, 激进蝴蝶优化, SSA中间表示

Abstract: The purpose of compilation optimization technology is to explore the optimization space in the program and improve the efficiency of program compilation or operation. Dead code elimination optimization is one of the widely used compilation optimization technologies. It aims to delete the unreachable codes in the program to improve the execution efficiency of the programs. In many applications, the execution path is often related to the input parameter values at runtime, and some branch paths are combined with the runtime parameter values. There may be dead codes. It is difficult to deal with these dead codes through the existing dead code elimination optimization. To this end, this paper proposes an aggressive butterfly optimization method that relies on data flow analysis. According to the possible values of dynamic runtime parameters, the method uses SSA intermediate representation to automatically generate the branch code similar to butterfly shape for the program. At the stage of program compilation in compiler, it provides feasible optimization basis for related optimization. Finally, the effectiveness and feasibility of this method are verified through experiments.

Key words: dead code elimination, compilation optimization, data flow analysis, aggressive butterfly optimization, SSA intermediate representation