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)
