for _, ai := range mheap_.allArenas {
		arena := mheap_.arenas[ai.l1()][ai.l2()]
		bitmap := arena.checkmarks

		if bitmap == nil {
			// Allocate bitmap on first use.
			bitmap = (*checkmarksMap)(persistentalloc(unsafe.Sizeof(*bitmap), 0, &memstats.gcMiscSys))
			if bitmap == nil {
				throw("out of memory allocating checkmarks bitmap")
			}
			arena.checkmarks = bitmap
		} else {
			// Otherwise clear the existing bitmap.

		return
	}

	// If the object is pinned, it's safe to store it in C memory. The GC
	// ensures it will not be moved or freed.
	if isPinned(src) {
		return
	}

	// It's OK if writing to memory allocated by persistentalloc.
	// Do this check last because it is more expensive and rarely true.
	// If it is false the expense doesn't matter since we are crashing.
	if inPersistentAlloc(uintptr(unsafe.Pointer(dst))) {
		return
	}