Walkabout-A Retargetable Dynamic Binary Translation Framework

Dynamic compilation techniques have found a renaissance in recent years due to their use in high-performance implementations of the Java™ language. Techniques origi-nally developed for use in virtual machines for such object-oriented languages as Smalltalk are now commonly used in Java virtual machines (JVM™) and Java just-in-time compilers. These techniques have also been applied to binary translation in recent years, most commonly appearing in binary optimizers for a given platform that improve the performance of binary programs while they execute.

The Walkabout project investigates and develops dynamic binary translation techniques that are based on properties of retargetability, ease of experimentation, separation of machine-dependent from machine-independent concerns, and good debugging support. Walkabout is a framework for experimenting with dynamic binary translation ideas, as well as techniques in related areas such as interpreters, instrumentation tools, and optimization.

In this report, we present the design of the Walkabout framework and its initial implementation. Tools generated from this initial framework include disassemblers, machine code interpreters (emulators), and binary rewriting tools for the SPARC® and x86 architectures.