return d.parseFieldLiteral(4, indexedNever)
	case b&224 == 32:
		// 6.3 Dynamic Table Size Update
		// Top three bits are '001'.
		// https://httpwg.org/specs/rfc7541.html#rfc.section.6.3
		return d.parseDynamicTableSizeUpdate()
	}

	return DecodingError{errors.New("invalid encoding")}
}

// (same invariants and behavior as parseHeaderFieldRepr)
func (d *Decoder) parseFieldIndexed() error {
	buf := d.buf