Several cache lines, determined by C_NUM_WAYS,
are grouped to form a set. Each set is accessed by the index bits part of the address,
see the previous figure. An address can be mapped to any of the cache lines, also called
ways, in a set. The way that is used when allocating a cache line is firstly any free
way in a set, secondly already allocated lines
replaced
by a Least Recently Used (LRU) algorithm.