if h.growing() {
		evacuate_faststr(t, h, h.nevacuate)
	}
}

func evacuate_faststr(t *maptype, h *hmap, oldbucket uintptr) {
	b := (*bmap)(add(h.oldbuckets, oldbucket*uintptr(t.BucketSize)))
	newbit := h.noldbuckets()
	if !evacuated(b) {
		// TODO: reuse overflow buckets instead of using new ones, if there
		// is no iterator using the old buckets.  (If !oldIterator.)

		advanceEvacuationMark(h, t, newbit)
	}
}

func advanceEvacuationMark(h *hmap, t *maptype, newbit uintptr) {
	h.nevacuate++
	// Experiments suggest that 1024 is overkill by at least an order of magnitude.
	// Put it in there as a safeguard anyway, to ensure O(1) behavior.
	stop := h.nevacuate + 1024
	if stop > newbit {
		stop = newbit
	}