• What's LLVMRuby

LLVMRuby is a set of bindings making the LLVM compiler infrastructure (llvm.org) usable from Ruby. This extention allows using LLVM as an abstract assembler and reflects a good chunk of the LLVM class hierarchy into Ruby. Included is an example of using this to build a simple JIT compiler, written entirely in Ruby, which is able to interact with the native Ruby 1.8/1.9 data types.

  • How to build

Get LLVM 2.9 from llvm.org/releases/2.9/llvm-2.9.tgz and build it separately following their instructions.

$ ./configure

Add the llvm bin directory to your path, extconf needs to be able to find llvm-conf:

$ export PATH=$PATH:/$LLVMDIR/Release/bin

Run rake

$ rake

Run the tests (you will need Rake installed)

$ rake test

Look in test.rb to see examples of use and start messing around. The project was recently reorganized in gem format with Ruby files in lib, and C/CPP and extension in ext. You will need to either load the library as a gem or make sure that both lib and ext dirs are in your load path.

  • Caveats

I primarily develop this on my home machine which is 64bit Fedora. I occasionally test it on a 32bit CentOS machine, and recently tested it on a 32bit MacBook. It built and passed tests with no issues. My knowledge of building either Ruby or LLVM on Windows is minimal. It should be doable, but I don't believe LLVM currently is usable with VC++, which is the main compiler for Ruby on Windows, so you may run into fun times trying to figure out a good way to make that go.

  • Things that definitely do not work right now

No attempt has been made to properly free LLVM objects. This probably isn't hard, LLVM api has easy to deal with memory management. Many LLVM objects end up owned by modules/execution engine and shouldn't be freed normally anyway.

There needs to be a lot more exception raising when arguments are of wrong number/type.

Malformed LLVM functions will cause the program to abort, even just from calling verify on a module. This seems like a bug in LLVM. Verification in theory is slow and should be used only for debugging, but it would nice if tests did not abort and die because of missing block terminators or whatever.

  • Copying

See the file COPYING

  • Author

For questions or answers, my email is: tomatobagby@gmail.com