// An Await opcode is used in the codegen for an async function to suspend
// execution until the given wait handle is finished. In eager execution,
// the state is suspended into a new AsyncFunctionWaitHandle object so that
// the execution can continue later. We have just completed an Await, so
// the new AsyncFunctionWaitHandle is now available, and it can predict
// where execution will resume.
void CmdNext::stepAfterAwait() {
auto topObj = vmsp()->m_data.pobj;
assertx(topObj->instanceof(c_AsyncFunctionWaitHandle::classof()));
auto wh = static_cast<c_AsyncFunctionWaitHandle*>(topObj);
auto func = wh->actRec()->func();
Offset nextInst = wh->getNextExecutionOffset();
assertx(nextInst != InvalidAbsoluteOffset);
m_stepResumableId = wh->actRec();
TRACE(2,
"CmdNext: patch for cont step after Await at '%s' offset %d\n",
func->fullName()->data(), nextInst);
m_stepResumable = StepDestination(func->unit(), nextInst);
}
// A AsyncESuspend is used in the codegen for an async function to setup
// a Continuation and return a wait handle so execution can continue
// later. We have just completed a AsyncESuspend, so the new
// Continuation is available, and it can predict where execution will
// resume.
void CmdNext::stepAfterAsyncESuspend() {
auto topObj = g_context->getStack().topTV()->m_data.pobj;
assert(topObj->instanceof(c_AsyncFunctionWaitHandle::classof()));
auto wh = static_cast<c_AsyncFunctionWaitHandle*>(topObj);
auto func = wh->getActRec()->m_func;
Offset nextInst = wh->getNextExecutionOffset();
assert(nextInst != InvalidAbsoluteOffset);
m_stepContTag = wh->getActRec();
TRACE(2,
"CmdNext: patch for cont step after AsyncESuspend at '%s' offset %d\n",
func->fullName()->data(), nextInst);
m_stepCont = StepDestination(func->unit(), nextInst);
}
