func (dt *dynamicTable) evict() {
	var n int
	for dt.size > dt.maxSize && n < dt.table.len() {
		dt.size -= dt.table.ents[n].Size()
		n++
	}
	dt.table.evictOldest(n)
}

func (d *Decoder) maxTableIndex() int {
	// This should never overflow. RFC 7540 Section 6.5.2 limits the size of
	// the dynamic table to 2^32 bytes, where each entry will occupy more than
	// one byte. Further, the staticTable has a fixed, small length.