Note that the author is not defending the use of SSE3 (https://en.wikipedia.org/wiki/SSE3 https://en.wikipedia.org/wiki/SSE3), the author is defending the use o

Note that the author is not defending the use of SSE3 (https://en.wikipedia.org/wiki/SSE3 https://en.wikipedia.org/wiki/SSE3), the author is defending the use of SSSE3 (https://en.wikipedia.org/wiki/SSSE3 https://en.wikipedia.org/wiki/SSSE3), which is something completely different. In fact, the whole point of this post is a novel use of the PSHUFB instruction, which comes from SSSE3. I happen to have a somewhat old laptop right next to me (it originally came with Windows Vista). According to /proc/cpuinfo, it does have SSE, SSE2, and SSSE3 (but not SSE3), so even that old laptop is already new enough to run the proposed algorithm.