honey-potion VS pl0c

Hi all! We are working on an eBPF backend for Elixir. It's called Honey Potion. The project is under development, but it is possible to write some useful programs at this point. For instance, in this video, one of the guys involved explains how to write a program to count system calls.

We have been working on an eBPF backend for the Elixir programming language. The current implementation is on this branch. EBPF is a bit like a virtual machine that runs on the Linux kernel. EBPF programs are typically used to implement network applications. The most interesting aspect of the backend is that Linux uses a verifier to ensure that eBPF programs always terminate and only access memory within allocated bounds.

Hi! We have been translating Elixir to C (which we translate to eBPF) in HoneyPotion. We used mostly Chapter 15 of Appel's Modern Compiler Implementation in Java to implement the code generator (that's "15. Functional Programming Languages"). I think the choice of C has been good thus far. The implementation of Elixir's pattern matching took much work, but if we had chosen a higher level target, we would still have to translate that to eBPF. Here's the entry point for the translator.

We have been working on a tool that translates Elixir to eBPF. We actually translate eBPF to C. Now that we have more stuff working, I really wonder if generating C was a good choice.

That's exactly what Honey Potion does, when we translate Elixir into Linux' eBPF!

> Some compilers tokenize while parsing, but for a different reason: it's faster and uses less memory to generate the AST

And some don't even generate an AST. :) Just read in and emit or interpret.

https://briancallahan.net/blog/20210814.html

Single-pass compiler tutorial

Let's Write a Compiler

I don’t think there will be an AST. https://briancallahan.net/blog/20210814.html: “We will be writing a single-pass compiler for a simple language and immediately output our final output code as soon as our compiler has enough information to do so”

That “as soon as” implies code will be generated before the entire program has been parsed.

Also, for me single-pass implies “no AST”, as you would need at least one pass to construct one, and iterating over an AST counts as another pass for me.