CREATE EXTENSION popcount;
ERROR:  extension "popcount" already exists
SELECT popcount256(15::bit(4));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(4));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(8));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(8));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(12));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(12));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(32));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(32));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(30::bit(32));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(127::bit(32));
 popcount256 
-------------
           7
(1 row)

SELECT popcount256(15::bit(256));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(256));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(512));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(512));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(b'10101010101010101010101010101010101101010101010101010101010101010101011010101010101010101010101010101010110101010101010101010101010101010101101010101010101010101010101010101011010101010101010101010101010101010110101010101010101010101010101010101101010101010101010101010101010101011010101010101010101010101010101010110101010101010101010101010101010101101010101010101010101010101010101011010101010101010101010101010101010110101010101010101010101010101010101101010101010101010101010101010101011010101010101010101010');
 popcount256 
-------------
         263
(1 row)

SELECT popcount256(15::bit(8192));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(8192));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(1234));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(1234));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(3000));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(3000));
 popcount256 
-------------
           3
(1 row)

SELECT popcount256(15::bit(8192));
 popcount256 
-------------
           4
(1 row)

SELECT popcount256(7::bit(8192));
 popcount256 
-------------
           3
(1 row)

SELECT sum(popcount256(x::bit(8192))) from generate_series(1,1000000) x;
   sum   
---------
 9884999
(1 row)

SELECT sum(popcount256(x::bit(8192))) from generate_series(1,1000000) x;
   sum   
---------
 9884999
(1 row)