public static double2 subadd(double2 a, double2 b)
{
if (Sse3.IsSse3Supported)
{
v128 temp = Sse3.addsub_pd(*(v128 *)&a, *(v128 *)&b);
return(*(double2 *)&temp);
}
else
{
return(a - math.select(b, -b, new bool2(false, true)));
}
}