On Wed, Dec 12, 2012 at 10:40 AM, Clark Gaebel <cgae...@uwaterloo.ca> wrote: > I just did a quick derivation from > http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2 to get > the highest bit mask, and did not reference FXT nor the containers > implementation. Here is my code: > > highestBitMask :: Word64 -> Word64 > highestBitMask x1 = let x2 = x1 .|. x1 `shiftR` 1 > x3 = x2 .|. x2 `shiftR` 2 > x4 = x3 .|. x3 `shiftR` 4 > x5 = x4 .|. x4 `shiftR` 8 > x6 = x5 .|. x5 `shiftR` 16 > x7 = x6 .|. x6 `shiftR` 32 > in x7 `xor` (x7 `shiftR` 1) > > This code is hereby released into the public domain. Problem solved.
I will integrate this into containers later today. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
