  We introduce a high-performance virtual machine (VM) written in a numerically
fast language like Fortran or C to evaluate very large expressions. We discuss
the general concept of how to perform computations in terms of a VM and present
specifically a VM that is able to compute tree-level cross sections for any
number of external legs, given the corresponding byte code from the optimal
matrix element generator, O'Mega. Furthermore, this approach allows to
formulate the parallel computation of a single phase space point in a simple
and obvious way. We analyze hereby the scaling behaviour with multiple threads
as well as the benefits and drawbacks that are introduced with this method. Our
implementation of a VM can run faster than the corresponding native, compiled
code for certain processes and compilers, especially for very high
multiplicities, and has in general runtimes in the same order of magnitude. By
avoiding the tedious compile and link steps, which may fail for source code
files of gigabyte sizes, new processes or complex higher order corrections that
are currently out of reach could be evaluated with a VM given enough computing
power.
