Rapid prototyping and compact testing of CPU emulators

In this paper, we propose a novel rapid prototyping technique to produce a high quality CPU emulator at reduced development cost. Specification mining from published CPU manuals, automated code generation of both the emulator and its test vectors from the mined CPU specifications, and a hardware-oracle based test strategy all work together to close the gaps between specification analysis, development and testing. The hardware-oracle is a program which allows controlled execution of one or more instructions on the CPU, so that its outputs can be compared to that of the emulator. The hardware-oracle eliminates any guesswork about the true behavior of an actual CPU, and it helps in the identification of several discrepancies between the published specifications vs. the actual processor behavior, which would be very hard to detect otherwise.