if (getJitCompilerOptions()["ion.warmup.trigger"] > 30) setJitCompilerOption("ion.warmup.trigger", 30); function Iterate(items) { for (var value of items) {} } var iterable = { *[Symbol.iterator]() { return "pass"; (yield* iterable); } }; for (var i = 0; i < 20; ++i) { Iterate(iterable); }