When ordering moves we push all captures with negative SEE values
to badCaptures[] array during the scoring phase.
This patch delays the costly SEE call up to when the move has been
picked up in pick_move_from_list(), this way we save some SEE calls
in case we get a cutoff.
It seems we have a speed gain of about 1-1.5 % in terms of nodes/sec
and profiling seems to confirm the small but real speed increase.
Idea from Pablo Vazquez on talkchess.com
http://www.talkchess.com/forum/viewtopic.php?t=29018&start=20
It would be a no functional change but actually it is not because
now sorting set is different and so std::sort(), that is not a
stable sort, does not guarantees the order of same scored moves to
remain the same as before.
After 952 games at 1+0 we are below error bar, almost equal just
6 games of difference (+2 ELO)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Marco Costalba
20224a5bbf