Modernization of Legacy Software

As hardware platforms age, manufacturers are less willing to support them and related technologies. Legacy weapons systems must eventually be modernized, but re-implementation of legacy software by hand is prohibitively expensive. A system is needed for automatically translating software written in obsolete languages like CMS-2 or assembly to a modern language like C. Previous attempts at translation have amounted to transliteration: they produced "high-level" code that closely mimics the low-level code. Some attempts even use global variables for registers. Translators that do more than this often assume that the low-level code was generated by a compiler, and hence adheres to certain conventions; such assumptions do not hold for legacy code. Under this OSD/NAVY SBIR contract, GrammaTech is developing a system for modernizing legacy software based on state-of-the-art static analysis.