Removing Redundant Arguments Automatically

TL;DR

This paper presents methods for analyzing and removing redundant arguments in programs modeled as term rewriting systems, aiming to optimize code by eliminating unnecessary parameters without altering program semantics.

Contribution

It introduces novel analysis and erasure techniques for redundant arguments in term rewriting systems, with a practical prototype implementation demonstrating effectiveness.

Findings

Redundant arguments can be identified and safely removed.

The erasure procedure preserves program semantics under certain conditions.

Prototype implementation shows practical applicability.

Abstract

The application of automatic transformation processes during the formal development and optimization of programs can introduce encumbrances in the generated code that programmers usually (or presumably) do not write. An example is the introduction of redundant arguments in the functions defined in the program. Redundancy of a parameter means that replacing it by any expression does not change the result. In this work, we provide methods for the analysis and elimination of redundant arguments in term rewriting systems as a model for the programs that can be written in more sophisticated languages. On the basis of the uselessness of redundant arguments, we also propose an erasure procedure which may avoid wasteful computations while still preserving the semantics (under ascertained conditions). A prototype implementation of these methods has been undertaken, which demonstrates the practicality of our approach.