fvm

fvm is a Clojure library for writing self-optimizing interpreters.

How it works

fvm provides a function called defnode for defining instruction nodes with the following signature:

(fvm/defnode <node-type> <opts> <handler-fn>)

• any node with the option {::fvm/jit? true} is considered a loop
• if such a node is executed frequently enough, its next execution is put in "trace-mode"
• in trace-mode, all the sub-nodes executed are logged in a "trace"
• the trace is effectively an unrolled version of the loop with function calls inlined
• once the node finishes executing, this trace is "compiled" into a Clojure function
• the compiled version is used on future executions of this node

Examples

ednlang is a simple stack-based concatenative language implemented using fvm.

ednlang is meant to showcase all the features of fvm, and is also used to test and profile fvm.

Work is ongoing to implement a lisp on top of fvm.

Status

This is EXPERIMENTAL software. Here be dragons.

License

Copyright © 2020 Divyansh Prakash

This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.

This Source Code may also be made available under the following Secondary Licenses when the conditions for such availability set forth in the Eclipse Public License, v. 2.0 are satisfied: GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version, with the GNU Classpath Exception which is available at https://www.gnu.org/software/classpath/license.html.