brainfuck-php

An optimizing brainfuck parser & interpreter written in PHP.

This is a rework of a very old project of mine, which was actually the first project I ever uploaded to GitHub!
If you want to see the old version, check out the old-version tag.
But be warned of the bad code :D

Note

Since this is just a little experiment, I won't go into too much detail about how it works, how to use it, or what exactly it does. Feel free to start a new discussion if you have any questions!

Requirements

• PHP 8.2 or newer

Usage

$ composer install

$ ./bin/bf ./examples/hello.bf
Hello World!

Feel free to check out all other example programs I have uploaded!
For example lost-kingdom.bf is pretty fun :)

Benchmarks

As far as I can see, this is one of, if not the fastest PHP brainfuck parser & interpreter around:

$ php -v
PHP 8.2.14 (cli) (built: Dec 21 2023 20:19:23) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.2.14, Copyright (c) Zend Technologies
    with Zend OPcache v8.2.14, Copyright (c), by Zend Technologies


# With only basic optimization like merging consecutive operators together:
$ time ./bin/bf ./examples/hanoi.bf
real    6m46,842s
user    6m46,457s
sys     0m0,144s

$ time php -dopcache.enable_cli=1 -dopcache.jit_buffer_size=100M -dopcache.jit=1255 ./bin/bf ./examples/hanoi.bf
real    3m25,252s
user    3m25,067s
sys     0m0,044s


# After adding the scan and clear opcodes:
$ time ./bin/bf ./examples/hanoi.bf
real    0m28,194s
user    0m28,132s
sys     0m0,036s

$ time php -dopcache.enable_cli=1 -dopcache.jit_buffer_size=100M -dopcache.jit=1255 ./bin/bf ./examples/hanoi.bf
real    0m15,726s
user    0m15,665s
sys     0m0,052s


# After adding the copy opcode:
$ time ./bin/bf ./examples/hanoi.bf
real    0m15,946s
user    0m15,881s
sys     0m0,056s

$ time php -dopcache.enable_cli=1 -dopcache.jit_buffer_size=100M -dopcache.jit=1255 ./bin/bf ./examples/hanoi.bf
real    0m9,347s
user    0m9,296s
sys     0m0,040s

If the above is not clear: the hanoi.bf brainfuck program only takes 9 seconds to run on my machine, which is pretty fast compared to where this project started at (7 whole minutes) and compared to other PHP brainfuck parsers & interpreters I could find on the internet!