Interflow: interprocedural flow-sensitive type inference and method duplication

Scala heavily relies on a number of object-oriented abstractions to support its feature-rich collections library. There are known techniques that optimize those abstractions away in just-in-time (JIT) compilers, but applying them in the ahead-of-time (AOT) setting is problematic. Profile-guided optimization (PGO) lets AOT compilers apply some of the same optimizations that JIT compilers employ, but it comes at a high complexity cost.