gistfile1.txt

, { "BlackBox" :
    { "name"      : "CLaSH.Sized.Vector.fold"
    , "type"      : "fold :: (a -> a -> a) -> Vec (n+1) a -> a"
    , "comment"   : "THIS ONLY WORKS FOR POWER OF TWO LENGTH VECTORS"
    , "templateD" :
"-- fold begin
fold_~SYM[0] : block
  function pow2Index (d,n : in natural) return natural is
  begin
    return (2 ** d - 2 ** n);
  end function;

  signal intermediate : ~TYPM[1](0 to (2*~LENGTH[~TYP[1]])-2);
  constant levels : natural := (natural (ceil (log2 (real (~LENGTH[~TYP[1]])))));
begin
  intermediate(0 to ~LENGTH[~TYP[1]]-1) <= ~ARG[1];

  tree_depth : for d in levels-1 downto 0 generate
    tree_nf_loop: for i in 0 to (natural(2**d) - 1) generate
      ~INST 0
        ~OUTPUT <= intermediate(pow2Index(levels+1,d+1)+i)~ ~TYPO~
        ~INPUT  <= intermediate(pow2Index(levels+1,d+2)+(2*i))~ ~TYPO~
        ~INPUT  <= intermediate(pow2Index(levels+1,d+2)+(2*i)+1)~ ~TYPO~
      ~INST
    end generate;
  end generate;

  ~RESULT <= intermediate((2*~LENGTH[~TYP[1]])-2);
end block;
-- fold end"
    }
  }