x = add(x, size-dataSize)
	}

	return x
}

// deductAssistCredit reduces the current G's assist credit
// by size bytes, and assists the GC if necessary.
//
// Caller must be preemptible.
//
// Returns the G for which the assist credit was accounted.
func deductAssistCredit(size uintptr) *g {
	var assistG *g
	if gcBlackenEnabled != 0 {

	// to do this before calling sysUsed because that may commit address space.
	bytesToScavenge := uintptr(0)
	forceScavenge := false
	if limit := gcController.memoryLimit.Load(); !gcCPULimiter.limiting() {
		// Assist with scavenging to maintain the memory limit by the amount
		// that we expect to page in.
		inuse := gcController.mappedReady.Load()
		// Be careful about overflow, especially with uintptrs. Even on 32-bit platforms

	// Omit idle marking time from the overall utilization here since it's "free".
	memstats.gc_cpu_fraction = float64(work.cpuStats.GCTotalTime-work.cpuStats.GCIdleTime) / float64(work.cpuStats.TotalTime)

	// Reset assist time and background time stats.
	//
	// Do this now, instead of at the start of the next GC cycle, because
	// these two may keep accumulating even if the GC is not active.
	scavenge.assistTime.Store(0)