基于动态分析的多面体模型非仿射扩展方法

摘要： 多面体模型只能表示循环中访存数组下标可以用仿射表达式表示的循环，针对这个限制设计一种基于动态分析的方法对多面体模型的表示范围进行扩展.该方法利用程序运行时的动态信息，将循环非仿射表达式中的循环全局参数用定值替换，推测生成非仿射循环的参数定值化版本，使之可以被多面体模型表示.该方法扩展了多面体模型的表示范围，使更多的代码区域可以被并行优化，提高了程序中SCoP的覆盖率，提高了程序运行的加速比.实验证明了该方法的有效性.

A Non-Affine Extension Method of Polyhedral Model Based on Dynamic Analysis

Abstract：The polyhedral model is now only applied in code regions with affine expressions in arrays’ indexes. A method is presented that extending polyhedral model to non affine expression. With the information acknowledged in runtime, non affine expressions can be transformed to affine expressions, which are led by parameters that do not change in the loop nest. Then a specialized version of the original loop is generated, which makes polyhedral techniques applicable. This method enables the polyhedral model to be applicable in more code regions. More SCoPs in the code regions are recognized and higher speedup is achieved, therefore the performance of the program is improved. The validity and efficiency of the presented method are demonstrated by a series of experiments.