Butterfly match-line structure and search method implemented thereby

A search method implemented by a butterfly match-line structure, applying to a content-addressable memory and comprising the following steps:

• allocating a plurality of memory cells from said content-addressable memory;
• utilizing at least one set of hierarchical match lines to cascade said memory cells with each pair of the diagonally-neighboring said memory cells of the different said match lines linked to each other;
• comparing the first layer of said memory cells against an input signal;
• if the result is a match case, comparing the next layer of said memory cells against said input signal;
• if the results are always match cases, performing comparisons successively until the last layer of said memory cells;
• and
• if a miss case occurs in one said memory cell, stopping the comparing operation with more succeeding said memory cells not compared but turned off.