Stockfish 1.7.1 displays weird mate scores

[Uri Blass]

I wonder how often stockfish has a big fail high that is a bad move and note that even if a big fail high from 0.00 evaluation is practically for a move that leads to a draw by the 50 move rule you then you still lose nothing from trusting the fail high.
Uri

Last time I tested enabling TT probe in PV (which fixes this behaviour), the difference was not measurable. And I've never so far observed this behaviour in real games, so there is no need to fix this. Accepting TT scores in PV causes so many difficult problems to deal with that I don't want it.

I suspect that the difference may be bigger at longer time control and I did not suggest to enable TT probe in PV

I suggested only that if you have a big fail high and fail low later at the same depth to trust the fail high and not to change the pv.

Uri

[mcostalba]

Code: Select all

bool deepChecks = (depth == -OnePly && staticValue >= beta - PawnValueMidgame / 8);

is easier to read.

Adding extra parentheses to the return statement would not be easier to read.
Redundant parentheses are in most cases bad for clarity.
The above example is an exception from this rule.

All IMHO. (Beauty is in the eye of the beholder)

Yes, that's exactly the reason.

As you and Sven have already pointed out, form the compiler point of view the two versions are identical, but I changed it for clarity.

[BBauer]

Looks like it is much faster with the Kiiski patch.

Code: Select all

29 -266 3135 140749324 Bc5+ Kc7 Ne8+ Kd7 Nxf6+ Ke6 Ng4 Qd3+ Kf4
30 -258 4222 200123976 Bc5+ Kc7 Ne8+ Kd7 Nxf6+ Ke6 Ng4 Qd3+ Kf4
31 -258 5971 295548223 Bc5+ Kc7 Ne8+ Kd7 Nxf6+ Ke6 Ng4 Qd3+ Kf4
31 -242 6426 317653665 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 -226 6505 321278015 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 -193 6635 325671430 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 -129 6825 331540362 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 +0 7100 345295021 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 +258 7763 378800150 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 +775 8696 423114107 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4 f3
31 +1810 12906 634000763 Ba5+ Kxa5 Nc4+ Kb5 Kf4 c5 d5 f5 Kg5 f4
31 +2509 17891 868739175 Ba5+ Kxa5 Nc4+ Kb5 Kf4 f5 Kg5 f4 f3 Qb6
32 +2973 18265 886341422 Ba5+ Kxa5 Nc4+ Kb5 Kf4 f5 Kg5 f4 f3 Qa4
33 +4824 18815 913314761 Ba5+ Qxa5 Nc4+ Kc7 Nxa5 Kd7 Kf4 Ke6 Nxc6
33 +6674 19164 930856205 Ba5+ Kxa5 Nc4+ Kb5 Kf4 f5 Kg5 f4 f3

or is it simply smp luck?
Results are optained with 4 threads on a 2.7 GHz machine.
kind regards
Bernhard