This is only experimental right now.

The goal of the project is to be able to run WebAssembly binaries from PHP directly. So much fun coming!

There is a toy program in tests/, written in Rust:

#[no_mangle]
pub extern "C" fn sum(x: i32, y: i32) -> i32 {
    x + y
}

This program compiles to WASM, with just compile-toy. We end up with a tests/toy.wasm binary file.

Then, we can execute it in PHP (!) with the tests/toy.php file:

<?php

require_once dirname(__DIR__) . '/lib/WASM.php';

$instance = new WASM\Instance(__DIR__ . '/toy.wasm');
$result = $instance->sum(5, 37);

var_dump($result);

And then, finally, enjoy by running:

$ php -d extension=wasm tests/toy.php
int(42)

This is a very preliminary status, but it works!

The src/ directory contains a Rust library that exposes an API to instanciate a WASM binary and invoke functions on it. It relies on the wasmi library. The src/ directory also exposes a C binding.

The extension/ directory contains a PHP extension, written in C, and exposing the C API from the Rust library to Zend Engine (the PHP VM). Few low-level functions are exposed, such as wasm_read_binary, wasm_new_instance, wasm_invoke_arguments_builder, wasm_invoke_function etc.

Then, the lib/ directory contains a more user-friendly PHP API built upon the API provided by the PHP extension, with class like WASM\Instance.

To compile the entire thing, run the following commands:

$ just rust
$ just php
$ php -d extension=wasm tests/toy.php

(Yes, you need just).

• Read a WASM binary,
• Instanciate a WASM binary,
• Arguments builder,
• Invoke function:
  • with i32 as arguments or returned value,
  • with i64 as arguments or returned value,
  • with f32 as arguments or returned value,
  • with f64 as arguments or returned value.
• User-friendly PHP API above the low-level PHP extension API,
• Expose memory:
  • Array view for i32,
  • Array view for i64,
  • Array view for f32,
  • Array view for f64.
  • Readable array view,
  • Writable array view.
• Import functions:
  • Specify signatures,
  • Support callable,
  • Support closure,
  • Support named function.

The entire project is under the BSD-3-Clause license. Please read the LICENSE file.