Modelling a JVM for polymorphic bytecode.

Abstract

In standard compilation of Java-like languages, the bytecode generated for a given source depends on both the source itself and the compilation environment. This latter dependency poses some unnecessary restrictions on which execution environments can be used to run the code. When using polymorphic bytecode, a binary depends only on its source and can be dynamically adapted to run on diverse environments. Dynamic linking is particularly suited to polymorphic bytecode, because it can be adapted to an execution environment as late as possible, maximizing the exibility of the approach. We analyze how polymorphic bytecode can be dynamically linked presenting a deterministic model of a Java Virtual Machine which interleaves loading and linking steps with execution. In our model, loading and execution phases are basically standard, whereas verication handles also type constraints, which are part of polymorphic bytecode, and resolution blends in verication.