via HtP the IBM Journal of Research and Development - Application of full-system simulation in exploratory system design and development:

This paper describes the design and application of a full-system simulation environment that has been widely used in the exploration of the IBM PowerPC(R) processor and system design. The IBM full-system simulator has been developed to meet the needs of hardware and software designers for fast, accurate, execution-driven simulation of complete systems, incorporating parameterized architectural models. This environment enables the development and tuning of production-level operating systems, compilers, and critical software support well in advance of hardware availability, which can significantly shorten the critical path of system development. The ability to develop early versions of software can benefit hardware development by identifying design issues that may affect functionality and performance far earlier in the development cycle, when they are much less costly to correct. In this paper, we describe features of the simulation environment and present examples of its application in the context of the Sony-Toshiba-IBM Cell Broadband Engine(tm) and IBM PERCS development projects.

Of particular note is the fact that such a

"...simulation enabled the Cell BE software team to begin application development three years in advance of hardware availability. Tight coordination among the simulation, architecture, and software development teams helped finalize the specification and enabled early feedback to be incorporated into the processor architecture."

One for my computer architecture and design students methinks!