Intel added the Galois Field instruction set (GFNI) extensions to their Sunny Cove and Tremont cores. What’s particularly interesting is that GFNI is the only new SIMD extension that came with SSE and VEX/AVX encodings (in addition to EVEX/AVX512), to allow it to be supported on all future Intel cores, including those which don’t support AVX512 (such as the Atom line, as well as Celeron/Pentium branded “big” cores).
I suspect GFNI was aimed at accelerating SM4 encryption, however, one of the instructions can be used for many other purposes. The extension includes three instructions, but of particular interest here is the Affine Transformation (GF2P8AFFINEQB), aka bit-matrix multiply, instruction.
There have been various articles which discuss out-of-band