Coun the number of bits set in a variable

[BumerSan]

I'm not a real programmer, but I can use your unit perfectly in my private projects.
If possible I would like a Function BitCount128(b: 128): integer;
Thanks for your great work.

[laoqiuqiu]

const
  M1: UInt64 = $5555555555555555;
  M2: UInt64 = $3333333333333333;
  M3: UInt64 = $0F0F0F0F0F0F0F0F;
  M4: UInt64 = $00FF00FF00FF00FF;
  M5: UInt64 = $0000FFFF0000FFFF;
  M6: UInt64 = $00000000FFFFFFFF;

Function BitCount64(V: UInt64): Integer; register;
begin
  V := (V and M1) + ((V shr 1) and M1);
  V := (V and M2) + ((V shr 2) and M2);
  V := (V and M3) + ((V shr 4) and M3);
  V := (V and M4) + ((V shr 8) and M4);
  V := (V and M5) + ((V shr 16) and M5);
  V := (V and M6) + ((V shr 32) and M6);
  Result := Integer(V);
end;

Function BitCount128(V: UInt128): Integer; register;
begin
  Result := BitCount64(V.dc0);      // c0 is low 64 bits
  if V.dc1 <> 0 then
    Inc(Result, BitCount64(V.dc1))  // c1 is high 64 bits
end;