Minimizing Go Runtime, Building a Simple JIT Compiler, and Exploring Self‑Hosted Compilation

The author revisits Go language fundamentals, explains why the Go runtime is heavyweight, and proposes a technique to bypass the default runtime by redefining the program entry point ( _rt0_amd64_linux ) and linking directly to a custom entry function.

Using the standard Go toolchain ( go tool compile , go tool pack , go tool link ), the article walks through the full compilation process, from source to object files, archives, and the final executable, demonstrating how the custom entry point avoids runtime initialization.

Next, the article introduces a simple Just‑In‑Time (JIT) compiler for a subset of Python bytecode, translating bytecode to an intermediate representation (IR) based on SSA/TAC, applying basic optimizations (e.g., eliminating redundant push / pop pairs and no‑op moves), and finally emitting x86‑64 machine code that is executed via mmap and a function pointer.

Finally, the author shows how Go’s self‑hosting capabilities can be leveraged with LLVM: parsing Go source with go/parser , converting the AST to LLVM IR, defining a built‑in printf function, and using clang to compile the IR into a native executable. The complete workflow demonstrates a minimal Go compiler that produces correct output.

The article concludes that these techniques illustrate the power of IR, JIT, and self‑hosting in modern compiler design, encouraging readers to experiment further.