Enigma
Another VM, Why? So I decided to dig into BEAM internals because I wanted to start contributing to Erlang development, and I learn best by building. That, plus writing this in Rust has been tons of fun (I also trust my Rust code a lot more than my C code).
Current aim is to be OTP 22 compatible, (sans the distributed bits for now). Performance? My TotallyLegit™ fibonacci benchmarks are currently on-par with OTP (albeit I'm missing 99% of the runtime).
Plan: implement all the instructions -> implement enough BIFs to get preloaded bootstrap to load -> implement enough to get the full system to boot -> OTP tests to run.
Installation
rustup to install latest rust (minimum version is 2018 edition).
cargo install to install the dependencies, cargo run to build. Expect heavy
crashes, but a basic spawn + send multi-process model already works.
Goals
- Explore using immix as a GC for Erlang
- Be able to run the Erlang bootstrap
- Be able to run Elixir
- Ideally one day, feature parity with OTP
- Write more documentation about more sparsely documented BEAM aspects (binary matching, time wheel, process monitors, etc).
(Initial?) non-goals
- Distributed Erlang nodes
- NIFs
Ideas/Experiments
- Process as a generator function (yield to suspend/on reduce)
TODO
-
full external term representation
-
bignum math
-
deep term comparison
-
GC!
-
exports global table? that way we can call any method
-
directly embed imports as some form of a pointer reference
-
focus on getting preloaded modules to load: {:preLoaded, [:atomics, :counters, :erl_init, :erl_prim_loader, :erl_tracer, :erlang, :erts_code_purger, :erts_dirty_process_signal_handler, :erts_internal, :erts_literal_area_collector, :init, :persistent_term, :prim_buffer, :prim_eval, :prim_file, :prim_inet, :prim_zip, :zlib]},
Special thanks
- Yorick Peterse's Inko, from which I've stolen the process scheduling code.
- @kvaks for ErlangRT which I've used for an extensive reference, along with his BEAM Wisdoms website.
- The BEAM Book
- bumpalo for the basis of bump allocation