Combining range and inequality information for pointer disambiguation

With this new algorithm, we are able to disambiguate pointers with offsets, that commonly occur in C programs, in a precise and efficient way. Together with this new abstract domain we describe several implementation decisions that let us produce a practical pointer disambiguation algorithm on top of the LLVM compiler. Our alias analysis is able to handle programs as large as SPEC CPU2006's gcc in a few minutes. Furthermore, it improves on LLVM's industrial quality analyses. As an extreme example, we have observed a 4x improvement when analyzing SPEC's lbm.