A Simple Algorithm for Global Value Numbering

TL;DR

This paper introduces a simplified algorithm for Global Value Numbering, an optimization technique for detecting redundant computations in programs, using value expressions for efficient equivalence representation.

Contribution

A new, simpler variant of Kildall's original GVN algorithm that employs value expressions for more compact and manageable equivalence information.

Findings

The algorithm effectively detects redundant computations.

It simplifies the implementation of GVN.

The approach improves efficiency over previous methods.

Abstract

Global Value Numbering(GVN) is a method for detecting redundant computations in programs. Here, we introduce the problem of Global Value Numbering in its original form, as conceived by Kildall(1973), and present an algorithm which is a simpler variant of Kildall's. The algorithm uses the concept of value expression - an abstraction of a set of expressions - enabling a representation of the equivalence information which is compact and simple to manipulate.