versusvoid/build.sh

## build.sh
clang -cc1 -emit-llvm-bc -triple=wasm32-unknown-unknown-wasm -std=c11 test.c
llc -filetype=obj test.bc -o test.o
wasm-ld --no-entry test.o -o test.wasm --export=aligned --export=misaligned --import-memory
wasm2wat test.wasm

## test.c
const char a[] = {1,2,3,4,5,6,7,8};
int aligned(int i)
{
	const int start = i % 3;
	int value = ((int)a[start] << 0) + ((int)a[start + 1] << 8) + ((int)a[start + 2] << 16) + ((int)a[start + 3] << 24);
	return i * value;
}

int misaligned(int i)
{
	return i * (*(int*)(a + (i%3)));
}

## test.html
<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>WASM aligned read test</title>
    </head>
    <body>
        <script>
            async function main() {
                const resp = await fetch('test.wasm');
                const wasm = await resp.arrayBuffer();
                const memory = new WebAssembly.Memory({initial:10, maximum:100});
                const module = await WebAssembly.instantiate(wasm, { env: { memory } });
                const iterations = 100000000;

                let start = new Date();
                for (let i = 0; i < iterations; ++i) {
                    module.instance.exports.aligned(i);
                }
                console.log('aligned');
                console.log(new Date() - start);

                start = new Date();
                for (let i = 0; i < iterations; ++i) {
                    module.instance.exports.misaligned(i);
                }
                console.log('misaligned');
                console.log(new Date() - start);
            };
            main();
        </script>
    </body>
</html>
	clang -cc1 -emit-llvm-bc -triple=wasm32-unknown-unknown-wasm -std=c11 test.c
	llc -filetype=obj test.bc -o test.o
	wasm-ld --no-entry test.o -o test.wasm --export=aligned --export=misaligned --import-memory
	wasm2wat test.wasm
	const char a[] = {1,2,3,4,5,6,7,8};
	int aligned(int i)
	{
	const int start = i % 3;
	int value = ((int)a[start] << 0) + ((int)a[start + 1] << 8) + ((int)a[start + 2] << 16) + ((int)a[start + 3] << 24);
	return i * value;
	}

	int misaligned(int i)
	{
	return i * ((int)(a + (i%3)));
	}
	<!doctype html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>WASM aligned read test</title>
	</head>
	<body>
	<script>
	async function main() {
	const resp = await fetch('test.wasm');
	const wasm = await resp.arrayBuffer();
	const memory = new WebAssembly.Memory({initial:10, maximum:100});
	const module = await WebAssembly.instantiate(wasm, { env: { memory } });
	const iterations = 100000000;

	let start = new Date();
	for (let i = 0; i < iterations; ++i) {
	module.instance.exports.aligned(i);
	}
	console.log('aligned');
	console.log(new Date() - start);

	start = new Date();
	for (let i = 0; i < iterations; ++i) {
	module.instance.exports.misaligned(i);
	}
	console.log('misaligned');
	console.log(new Date() - start);
	};
	main();
	</script>
	</body>
	</html>