Compiling Gallina to go for the FSCQ file system

Abstract

Over the last decade, systems software verification has become increasingly practical. Many verified systems have been written in the language of a proof assistant, proved correct, and then made runnable using code extraction. However, due to the rigidity of extraction and the overhead of the target languages, the resulting code's CPU performance can suffer, with limited opportunity for optimization. This thesis contributes CoqGo, a proof-producing compiler from Coq's Gallina language to Go. We created Go', a stylized semantics of Go which enforce linearity, and implemented proof-producing compilation tactics from Gallina to Go' plus a straightforward translation from Go' to Go. Applying a prototype of CoqGo, we compiled a system call in the FSCQ file system, with minimal changes to FSCQ's source code. Taking advantage of the increased control given by CoqGo, we implemented three optimizations, bringing the system call's CPU performance to 19% faster than the extracted version.