METHOD AND SYSTEM FOR THE EFFICIENT UNROLLING OF LOOP NESTS WITH AN IMPERFECT NEST STRUCTURE

摘要

A computer implemented method system and computer program product for efficient unrolling of imperfect loop nests. A virtual iteration space can be determined based on a UF (Unroll Factor) and the iteration space for each dimension of a nested loop can be divided into a residual iteration space and a non-residual iteration space utilizing unroll-and-jam transformation. The non-residual iteration space for one dimension can be utilized for categorizing the residual and non-residual iteration space for next dimension. This approach can be applied recursively to all dimensions and the non-residual iteration from last dimension can be removed in order to get a clean perfect loop nest. Such an approach can also be applied to triangular loop nests and nested loops having three or more dimensions.