Fibonacci in My Language

In the past few days I have been plugging away at writing a language that compiles directly to WASM. You might say, there are many languages that compile to WASM, what makes this one special? And the answer is "nothing". Yet, anyway. All I have is a few binary expressions and loops. There is only one type: int, which is i32. I have not even implemented function calls yet!

Nonetheless, I passed today a tiny milestone. My language can now calculate Fibonacci sequences!

Here is the full module:

export fn fibonacci(n: int) int {
	if (n <= 0) return 0;

	var a, b, i = 0, 1, 1;
	while (i < n) {
    		const next = a + b;
    		a, b = b, next;
    		i += 1;
	};

	return b;
}

Which is given to my compiler producing WASM in text format, which is then passed to Binaryen's wasm-as and wasm-opt tools to give us this binary, with a break where the code section (0A) begins.

00000000 | 00 61 73 6D  01 00 00 00  01 06 01 60  01 7F 01 7F | ▁asm•▁▁▁•••`••••
00000010 | 03 02 01 00  07 0D 01 09  66 69 62 6F  6E 61 63 63 | •••▁•←•→fibonacc
00000020 | 69 00 00                                           | i▁▁
00000023 | 0A 38 01 36  01 03 7F 20  00 41 00 4C  04 40 41 00 | ↵8•6•••␣▁A▁L•@A▁
00000033 | 0F 0B 41 01  21 01 41 01  21 02 03 40  20 00 20 01 | ••A•!•A•!••@␣▁␣•
00000043 | 4A 04 40 20  03 20 02 22  03 6A 21 02  20 01 41 01 | J•@␣•␣•"•j!•␣•A•
00000053 | 6A 21 01 0C  01 0B 0B 20  02 0B                    | j!•••••␣••

Which is then invoked with the exported function name of fibonacci in any WASM runtime to give you the result you need!

% ❭ just invoke fibonacci 10
| fibonacci 10
> 55

Nifty, hah?

Three Days Leter

I can do function calls now! Here is the naive Fibonacci:

export fn fibonacci(n: int) int {
	if (n <= 1) return n;
	return fibonacci(n: n - 1) + fibonacci(n: n - 2);
}

00000000 | 00 61 73 6D  01 00 00 00  01 06 01 60  01 7F 01 7F | ▁asm•▁▁▁•••`••••
00000010 | 03 02 01 00  07 0D 01 09  66 69 62 6F  6E 61 63 63 | •••▁•←•→fibonacc
00000020 | 69 00 00 0A  1E 01 1C 00  20 00 41 01  4C 04 40 20 | i▁▁↵•••▁␣▁A•L•@␣
00000030 | 00 0F 0B 20  00 41 01 6B  10 00 20 00  41 02 6B 10 | ▁••␣▁A•k•▁␣▁A•k•
00000040 | 00 6A 0B                                           | ▁j•

Takes a bit longet to compute than the loop, though.