A JIT Compiler in 380 Lines of Ruby

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Unless I am mistaken, I think the title could do with being changed. It looks to me like the Jit compiler is written in C++. LLVM is not written in Ruby. What is implemented in Ruby here is a version of the toy Kaleidoscope language which is given as an example of how to use the LLVM Jit on the LLVM website.

Are the LLVM bindings for Ruby up-to-date? I thought about using them last night for a while, but ended up deciding to use peg to create a recursive descent parser for my language and am going to write some pretty generic code to do the AST myself. That way I can keep everything in C/C++.

You might be interested by the first steps that I have taken to generate llvm IR from boost::spirit (for the peg parser) even if the languages where too simple to warrant an ast. https://github.com/scientific-coder/Computer-Languages

Thanks, though I already have a small language working with the LLVM Jit that accepts the language described by this grammar: http://selmer.warwick.ac.uk/c.grm

I'm in the process of rewriting it to use peg though, as I was using a parser generator that is not open source, and it started to bug me that it wasn't.

> Are the LLVM bindings for Ruby up-to-date?

I believe so; MacRuby is under pretty serious development by a team within Apple.

The Kaleidoscope language reminds me of the hoc language. In Chapter 8 of the book "The Unix Programming Environment", Brian Kernighan and Rob Pike used hoc as an example to demonstrate how to use yacc, lex, and make to develop a compiler.

In hoc, you have control flows and can define your own functions. Unfortunately, hoc lost the battle to bc, that's why it's rarely known in the Unix community.