On Sun, Jan 12, 2003 at 01:46:52AM +0100, Thomas Harte wrote in widescreen: > There is an entire web page somewhere dedicated to getting fast sqrts. I've > seen one > which uses only a 256 or 512 byte table but can do a 16bit sqrt in less than > 100 cycles.
Don't know how that works, but just out of interest, the fastest pure-code integer sqrt routine I know (producing an 8-bit number from a 16-bit input) has a loop of a bit over 100 cycles executed 8 times. It's based on this: x=arg(1)/2**16 p=0 do 8 x=4*x p=p+p if x >= p+1 then do x=x-(p+1) p=p+2 end end p=p/2 return p imc (who isn't here really)