internal static v128 SByteToShort(v128 x) { if (Sse4_1.IsSse41Supported) { return(Sse4_1.cvtepi8_epi16(x)); } else if (Sse2.IsSse2Supported) { return(Sse2.unpacklo_epi8(x, Sse2.cmpgt_epi8(default(v128), x))); } else { throw new CPUFeatureCheckException(); } }