(17 . 6)(17 . 7)
------------------------------------------------------------------------------
------------------------------------------------------------------------------

with Words;    use Words;
with Word_Ops; use Word_Ops;
with W_Pred;   use W_Pred;
with W_Shifts; use W_Shifts;
(25 . 7)(26 . 7)
package body FZ_Measr is
   
   -- Find the index of eldest nonzero bit ( 0 if none, or 1 .. FZBitness )
   function FZ_Measure(N : in FZ) return Word is
   function FZ_Measure(N : in FZ) return FZBit_Index is
      
      -- The result (default : 0, will remain 0 if N is in fact zero)
      Index     : Word := 0;
(54 . 14)(55 . 17)
      
      -- Find, in constant time, eldest non-zero bit in that Word:
      for b in 1 .. Bitness loop
         
         -- If W is non-zero, advance the Index...
         Index := W_Mux(Index + 1, Index, W_ZeroP(W));
         Index := Index + W_NZeroP(W);
         
         -- ... in either case, advance W:
         W     := Shift_Right(W, 1);
         
      end loop;
      
      -- If N = 0, result will be 0; otherwise: index of the eldest 1 bit.
      return Index;
      return FZBit_Index(Index);
      
   end FZ_Measure;