> On Fri, Jun 13, 2003 at 03:16:24PM -0400, George Woltman wrote: > > 2) This case results from the way my C compiler treats floating point NaN. > > NaN stands for not a number. If NaN is converted to an integer, the integer > > is zero. So if the FFT data is all NaNs, prime95 will report a prime. > > I expect this is a FAQ and apologize in advance, but in the age of > SSE2 integer instructions why is it still necessary to use floating > point calculations?
precision. The extended FP multiply has 64 bits of mantissa. SSE2 is, I believe, restricted to 32bit multiplies, so it would take 4 times as many to equal one 64bit (gross simplification, but sufficient for the purposes here). _________________________________________________________________________ Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
