WATaBoy: JIT-Ing Game Boy Instructions to WASM Beats a Native Interpreter

A Game Boy emulator called WATaBoy was built to demonstrate that JIT-compiling CPU instructions to WebAssembly bytecode can outperform a native interpreter, leveraging Apple's exception allowing JIT in web browsers. The project serves as a proof-of-concept and benchmark showing that this technique—previously unexplored for console emulators—can deliver performance gains by having the browser's JavaScript engine further compile the Wasm bytecode to native machine code.