Update and Restructure Legacy Code for ( or Before ) Parallel Processing

Transformation of an old large sequential applications into a parallel version is still a big challenge in the field of parallel computing. This paper presents a set of transformations to be applied on a medium/large numerical legacy code program having in mind the final objective of parallel computing. The steps are oriented to improve source code while preserving the software external behavior. Each of these transformations has been selected at least to turn old Fortran source code more readable and understandable in order to upgrade it and make it easier to be parallelized.