5987130afd
Emscripten strongly advises the use of optimisation when compiling with
ASYNCIFY enabled. Testing the difference betwen O3 and Os for various
configurations gives:
flags firmware.wasm micropython.js perf
-O3 -s ASYNCIFY 1342003 212845 0 (baseline)
-O3 -s ASYNCIFY -s WASM=0 - 7064750 -30%
-O3 367131 196569 +140%
-O3 -s WASM=0 - 2818260 +30%
-Os -s ASYNCIFY 1135450 213064 +40%
-Os -s ASYNCIFY -s WASM=0 - 6239768 -30%
-Os 295028 196569 +180%
-Os -s WASM=0 - 2271358 +30%
The first row is prior to this commit. The second and third columns show
firmware size (add them to get the total size). The fourth column shows
the approximate change in performance compared to the baseline. The
performance was measured using run-perfbench.py and the error was large, up
to 20%, although general trends in the change in performance could still be
seen.
In summary, using using Os instead of O3 makes it a little bit faster in
all cases, and smaller output (wasm/js) in all cases.
Signed-off-by: Damien George <damien@micropython.org>
|
||
|---|---|---|
| .. | ||
| Makefile | ||
| README.md | ||
| library.h | ||
| library.js | ||
| main.c | ||
| modutime.c | ||
| mpconfigport.h | ||
| mphalport.c | ||
| mphalport.h | ||
| node_run.sh | ||
| qstrdefsport.h | ||
| wrapper.js | ||
README.md
MicroPython WebAssembly
MicroPython for WebAssembly.
Dependencies
Building webassembly port bears the same requirements as the standard MicroPython ports with the addition of Emscripten (and uglify-js for the minified file).
The output includes micropython.js (a JavaScript wrapper for the
MicroPython runtime) and firmware.wasm (actual MicroPython compiled to
WASM).
Build instructions
In order to build micropython.js, run:
$ make
To generate the minified file micropython.min.js, run:
$ make min
Running with Node.js
Access the repl with:
$ node build/micropython.js
Stack size may be modified using:
$ node build/micropython.js -X stack=64K
Where stack size may be represented in Bytes, KiB or MiB.
MicroPython scripts may be executed using:
$ node build/micropython.js hello.py
Alternatively micropython.js may by accessed by other javascript programs in node using the require command and the general API outlined below. For example:
var mp_js = require('./build/micropython.js');
mp_js_init(64 * 1024);
mp_js_do_str("print('hello world')\n");
Running with HTML
The prerequisite for browser operation of micropython.js is to listen to the
micropython-print event, which is passed data when MicroPython code prints
something to stdout. The following code demonstrates basic functionality:
<!doctype html>
<html>
<head>
<script src="build/micropython.js"></script>
</head>
<body>
<pre id="micropython-stdout"></pre>
<script>
document.addEventListener("micropython-print", function(e) {
let output = document.getElementById("micropython-stdout");
output.innerText += e.data;
}, false);
var mp_js_startup = Module["onRuntimeInitialized"];
Module["onRuntimeInitialized"] = async function() {
mp_js_startup();
mp_js_init(64 * 1024);
mp_js_do_str("print('hello world')");
};
</script>
</body>
</html>
MicroPython code execution will suspend the browser so be sure to atomize usage within this environment. Unfortunately interrupts have not been implemented for the browser.
Testing
Run the test suite using:
$ make test
API
The following functions have been exposed to javascript.
mp_js_init(stack_size)
Initialize MicroPython with the given stack size in bytes. This must be called before attempting to interact with MicroPython.
mp_js_do_str(code)
Execute the input code. code must be a string.
mp_js_init_repl()
Initialize MicroPython repl. Must be called before entering characters into the repl.
mp_js_process_char(char)
Input character into MicroPython repl. char must be of type number. This
will execute MicroPython code when necessary.