ASYNCIFY_STACK_SIZE seems a little low

[yar2001]

Hi, thank you for your amazing library. Recently I met a problem related to asyncify stack memory region.

Run this code in node.js:

const { newAsyncContext } = require('quickjs-emscripten');

async function main() {
  const context = await newAsyncContext();
  let times = 0;
  const fooHandle = context.newAsyncifiedFunction('foo', async () => {
    times++;
    console.log('foo called', times);
  });

  fooHandle.consume((fn) => context.setProp(context.global, 'foo', fn));

  await context.evalCodeAsync(`
function a(){
  foo();
  a();
}
a();
`);
}

main();

And it will output:

foo called 1
foo called 2
foo called 3
foo called 4
foo called 5
foo called 6
foo called 7
foo called 8
foo called 9
foo called 10
foo called 11
foo called 12
Aborted(RuntimeError: unreachable)
/home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/generated/emscripten-module.WASM_RELEASE_ASYNCIFY.js:147
            a.onAbort(b); b = "Aborted(" + b + ")"; B(b); H = !0; b = new WebAssembly.RuntimeError(b + ". Build with -sASSERTIONS for more info."); l(b); throw b; }
                                                                      ^

RuntimeError: Aborted(RuntimeError: unreachable). Build with -sASSERTIONS for more info.
    at F (/home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/generated/emscripten-module.WASM_RELEASE_ASYNCIFY.js:147:71)
    at V (/home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/generated/emscripten-module.WASM_RELEASE_ASYNCIFY.js:195:13)
    at Aa.c.<computed> (/home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/generated/emscripten-module.WASM_RELEASE_ASYNCIFY.js:202:87)
    at /home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/generated/emscripten-module.WASM_RELEASE_ASYNCIFY.js:217:66
    at /home/yar2001/Documents/code/warriors-mono/node/node_modules/quickjs-emscripten/dist/module.js:130:25

Node.js v18.13.0

The aborted(runtimeerror: unreachable) error is likely caused by a stack overflow in the asyncify stack memory region. Notice that the function is nested 12 times and is unsuitable for some use cases (such as a little complicated web service). The linker option ASYNCIFY_STACK_SIZE is related to the size of the memory region, so maybe we can increase it to 81920 or more (20x than default).

[justjake]

Absolutely, I’m glad to accept a PR.