The document discusses and benchmarks various string search algorithms, including Quick Search, strstr, and a custom implementation using SSE4.2 instructions. It finds that for short substrings, strstr in GCC utilizing SSE4.2 performs best, while for longer substrings, a modified Quick Search algorithm is faster. The author's own implementation using pcmpestri outperforms all other algorithms, bei
![Quick Search algorithm and strstr](https://cdn-ak-scissors.b.st-hatena.com/image/square/5d9dd301d5534ec1c25fa8223d47e1da9e30e69e/height=288;version=1;width=512/https%3A%2F%2Fcdn.slidesharecdn.com%2Fss_thumbnails%2Fx86opti3-120331025552-phpapp02-thumbnail.jpg%3Fwidth%3D640%26height%3D640%26fit%3Dbounds)