tor-browser

ion-inlinedcall-resumepoint.js (1195B)

---

var invalidatedFunction = function() { return false; }

var counter = 0;

function maybeInvalidate(iplusk) {
   if (iplusk === 0) {
       // This should happen only once; it will invalidate the call frame of
       // the ion() function, which should rewind to just after the wasm call
       // (if it got its own resume point).
       // Before the patch, the wasm call doesn't get its resume point, so
       // it's repeated and the importedFunc() is called once too many.
       counter++;
       invalidatedFunction = function () { return true; };
   }
}

function importedFunc(k) {
   for (let i = 100; i --> 0 ;) {
       maybeInvalidate(i + k);
   }
}

let { exports } = new WebAssembly.Instance(
   new WebAssembly.Module(
       wasmTextToBinary(`
       (module
           (func $imp (import "env" "importedFunc") (param i32))
           (func (export "exp") (param i32)
               local.get 0
               call $imp
           )
       )
       `)
   ), {
       env: {
           importedFunc
       }
   }
);

function ion(k) {
   exports.exp(k);
   invalidatedFunction();
}

for (let k = 100; k --> 0 ;) {
   ion(k);
}

assertEq(counter, 1);