General Program Synthesis Using Guided Corpus Generation and Automatic Refactoring

Abstract

Program synthesis aims to produce source code based on a user specification, raising the abstraction level of building systems and opening the potential for non-programmers to synthesise their own bespoke services. Both genetic programming (GP) and neural code synthesis have proposed a wide range of approaches to solving this problem, but both have limitations in generality and scope. We propose a hybrid search-based approach which combines (i) a genetic algorithm to autonomously generate a training corpus of programs centred around a set of highly abstracted hints describing interesting features; and (ii) a neural network which trains on this data and automatically refactors it towards a form which makes a more ideal use of the neural network's representational capacity. When given an unseen program represented as a small set of input and output examples, our neural network is used to generate a rank-ordered search space of what it sees as the most promising programs; we then iterate through this list up to a given maximum search depth. Our results show that this approach is able to find up to 60% of a human-useful target set of programs that it has never seen before, including applying a clip function to the values in an array to restrict them to a given maximum, and offsetting all values in an array.

Multi-donor Neural Transfer Learning for Genetic Programming

“…We use a Turing-complete language for synthesis (previously used by the authors of [39]), which can be cross-compiled directly into C/Java/Python. Unusually, for general program synthesis, the language features primitive loop operators, variable declarations, and conditional branch operators; a full listing of its operators is given in Appendix A.…”