How QEMU executes foreign code: an inside look at the Tiny Code Generator

This article from YADRO on Habr provides an in-depth look at the internal workings of QEMU, specifically the Tiny Code Generator (TCG). QEMU is renowned for its ability to emulate various processor architectures, allowing programs compiled for one platform to run on an entirely different one. The author analyzes the JIT compilation process in detail, using the RISC-V architecture to demonstrate how machine instructions are converted into an intermediate representation and then into target code. The material covers the mechanisms of translation block formation, the role of block chaining, and the use of longjmp to optimize transitions. This technical breakdown is valuable for developers interested in low-level programming, emulation, and virtualization principles. The article offers a deep understanding of how QEMU achieves cross-platform compatibility at the instruction level without requiring hardware support from the host system.