Retrofitting JIT Compilers into C Interpreters

Article

• Technique to add JIT compilation to existing C-based interpreters
• Uses a modified LLVM fork to enable runtime IR tracing
• Achieves speedups without rewriting the interpreter from scratch

Discussion

• Commenters impressed: compile arbitrary C with forked LLVM, get JIT tracing
• Caveat: ~2x speedup vs Lua baseline, while LuaJIT achieves 5–10x
• One commenter needed to re-read to grasp it’s interpreters written in C, not a C interpreter
• Self-deprecating awe: ‘posts like this make me realize I don’t even rate as a computing nerd’

Discuss on HN