Practical Verification Condition Generation for a Bytecode Language

Automatic program verifiers typically generate verification conditions from the program and discharge them with an automated theorem prover. An important consideration is the manner in which program code and invariants are expressed. We have developed a bytecode language (similar, in spirit, to Java bytecode) on which verification is performed. This serves as both an intermediate language for use within the compiler, and a binary format with which dependencies (e.g. for libraries) can be resolved. Our bytecode language is a three-address code with semi-structured control-flow. Program code and invariants are represented uniformly to ensure bytecode programs are compact. In this paper, we present our bytecode language and outline a verification condition generator based on a path-sensitive forward-propagation algorithm.