index with nulls

As part of yesterday's patch, I fixed a problem with indexing of nulls.
The old code did:


                    mask = (finalbit << 1) - 1;
                    if ((~n) & mask)
                        slow=1;

when it meant to do:

                    mask = (1 << finalbit) - 1;
                    if ((~n) & mask)
                        slow=1;

This may explain some problems people were reporing.

--
Bruce Momjian
maillist@candle.pha.pa.us