
Use packed 8-bit operations rather than unpack to 16-bit. Avoid spills. ~1.97x speedup on Haswell (x86-64). ~3.09x speedup on Haswell (x86 32-bit).
Use packed 8-bit operations rather than unpack to 16-bit. Avoid spills. ~1.97x speedup on Haswell (x86-64). ~3.09x speedup on Haswell (x86 32-bit).