  In this paper, we introduce the concept of a virtual machine with
graph-organised memory as a versatile backend for both explicit-state and
abstraction-driven verification of software. Our virtual machine uses the LLVM
IR as its instruction set, enriched with a small set of hypercalls. We show
that the provided hypercalls are sufficient to implement a small operating
system, which can then be linked with applications to provide a
POSIX-compatible verification environment. Finally, we demonstrate the
viability of the approach through a comparison with a more
traditionally-designed LLVM model checker.
