Whole program type driven optimizations

EDIC candidacy exam
Exam president: Prof. Viktor Kuncak
Thesis advisor: Prof. Martin Odersky
Co-examiner: Prof. Christoph Koch

Abstract
Scala has a rich set of high level type abstractions that unfortunately can come with a cost on the performance of the generated code. When using external libraries (such as the standard library) the compiler must take conservative decisions to ensure compatibility of the interfaces. In Dotty we now have Tasty a precompiled AST representation of the program. It could be used to get all the high level abstractions information that is usually gone when linking with a library and even re-optimize the parts of the library that are needed for this particular application.

Background papers
Call graphs for languages with parametric polymorphism, by Petrashko D., et al.
Practical and effective higher-order optimizations, by Bergström L., et al.
Design and implementation of generics for the .NET Common language runtime, by Kennedy A., Syme D.