Hacker News Reader

Does anyone code directly in LLVM IR? I've had the thought of toying with it as a better portable assembly with a crazy optimizer behind it...but since the LLVM folk want it to be an implementation detail they warn against it due to how volatile it is across versions.

I'd be really interested to hear experiences of people who have done it though, even as a toy.

View on HN

I've coded directly in LLVM IR a few times (mostly for testing). It's not pleasant, primarily because you have to manage the SSA construction yourself, although the CFG can also be annoying.

There is a small, very restrictive class of LLVM IR that is going to be effectively stable, and even portable. Stripping debug information goes a long way to making your IR readable by newer versions of LLVM, and staying away from C ABI compatibility (especially structs) can make your code somewhat portable.

LLVM IR isn't exactly portable, so that doesn't really work.

The bitcode variant used by Apple for their OSes tends to be more clean in that regard.

Reply on news.ycombinator.com