关键词: 编译优化，指令级并行，谓词代码，指令调度

Abstract: A lot of branch instructions in program severely restrict the exploiting of parallelism of the architecture and the compiler. One of the major challenges to exploit effectively instruction level parallelism is overcoming the limitations imposed by branch instructions. Predicated execution can effectively delete branch instructions, and convert branch instructions to predicated code, which enlarges instruction scheduling scope and removes branch misprediction penalties.hhis paper described compiler optimization technology based on predicated code, such as instruction scheduling, software pipeline, register allocation, instruction merging. An instruction scheduling algorithm based on predicated code was designed and implemented. The experimental results show that compiler optimization based on predicated code can improve instruction parallelism degree, shorten code execution time effectively, and improve greatly the program' s performance.

Key words: Compiler optimization, Instruction level parallelism, Predicated code, Instruction scheduling