WASM Metal

A bare metal physical implementation of WebAssembly. That's right, a WebAssembly CPU. Inspired in part by this amazing talk.

Development

GUI Microarchitecture Simulator

git clone https://github.com/lastmjs/wasm-metal.git
cd wasm-metal
npm install
npm start

Go to http://localhost:5000 in your web browser.

RTL Microarchitecture Simulator

Not implemented yet.

Loading Microarchitecture Implementation to FPGA

Not implemented yet.

Roadmap

• Understand the WebAssembly ISA
• Implement the mircoarchitecture in HTML/CSS/JavaScript
  • This will be a GUI simulator of the microarchitecture
  • This simulator will become the specification for the microarchitecture
  • It will allow us to quickly experiment with hardware configurations
  • It will allow us to iterate and learn how the microarchitecture should work
• Implement the microarchitecture as an RTL design in an HDL
• Simulate the RTL design
• Test the implementation on an FPGA
• Design the ASIC

Why is this a good idea?

• Maybe it's not, but who cares
• The world is moving to WebAssembly
• Some of the biggest and potentially most world-changing projects are implementing their virtual machines as WebAssembly virtual machines (DFINITY, Ethereum)
• The bytecode is being designed as a compilation target for low-level languages first
• The bytecode is meant to execute at near-native speeds on a variety of underlying ISAs
• Java processors already offer potential benefits, even being compilation targets for a high-level language
• Cutting out the translation from WebAssembly to the underlying ISAs could provide efficiency benefits
• We could get rid of WebAssembly virtual machines entirely, and replace them with WebAssembly physical machines
• If all SIM cards are Java processors, imagine what WebAssembly processors could do. I'm betting that WebAssembly is a better bytecode than Java bytecode for what Java bytecode is doing with microcontrollers, so WebAssembly could take over all spaces that Java processors currently have

Prior art

• https://en.wikipedia.org/wiki/Jazelle
• https://stackoverflow.com/questions/1153076/does-android-castrate-the-arms-jazelle-technology
• https://en.wikipedia.org/wiki/Lisp_machine
• https://en.wikipedia.org/wiki/Java_processor
• https://en.wikipedia.org/wiki/High-level_language_computer_architecture