Merge branch 'simplify_eval' of https://github.com/glinscott/Stockfish

Test results are looking good after 12500 games.

ELO: 6.55 +- 99%: 8.02 95%: 6.09
LOS: 99.99%
Wins: 1968 Losses: 1732 Draws: 8813

Also, here are the noise.py results, which seem to have stabilized:
Games: 12526 , result: [1969, 1734, 8823]
Estimated ELO: 6.94963842777
Noise as function of number of games:
['81.89', '565.26', '110.87', '104.39', '38.22', '49.98', '18.56', '16.76',
'11.02', '8.90', '17.36', '9.84', '10.81', '5.13', '6.22', '3.32', '5.83',
'7.21', '15.27', '1.63', '4.04', '9.51', '0.54', '0.75', '1.06', '2.93',
'4.59', '6.85', '13.62', '9.87', '14.74', '20.46', '22.18', '24.33', '31.02',
'34.99', '35.22', '33.22', '32.46', '37.02', '29.10', '36.34', '42.11', '39.33',
'26.16', '28.25', '35.42', '31.04', '29.26', '23.91', '22.52', '23.49', '20.00',
'24.39', '17.22', '16.50', '10.69', '9.15', '9.57', '4.77', '6.67', '3.87', '2.57',
'2.84', '2.60', '3.32', '2.08', '2.93', '4.47', '4.41', '4.83', '4.86', '6.40',
'5.98', '6.10', '6.83', '5.83', '6.22', '5.71', '8.52', '9.25', '5.98', '7.52',
'7.76', '8.76', '8.55', '8.64', '7.19', '5.83', '4.59', '4.77', '4.26', '4.98',
'5.29', '5.41', '4.92', '5.59']

bench: 5229106

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 49dc07fe671ef0885ca9b5fbfd29a8fd2cc885ad..984a85a65e0492c3daaa46ddc72f06709ae32487 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -577,18 +577,6 @@ Value do_evaluate(const Position& pos, Value& margin) {
 
         mobility += MobilityBonus[Piece][mob];
 
-        // Add a bonus if a slider is pinning an enemy piece
-        if (   (Piece == BISHOP || Piece == ROOK || Piece == QUEEN)
-            && (PseudoAttacks[Piece][pos.king_square(Them)] & s))
-        {
-            b = BetweenBB[s][pos.king_square(Them)] & pos.pieces();
-
-            assert(b);
-
-            if (!more_than_one(b) && (b & pos.pieces(Them)))
-                score += ThreatBonus[Piece][type_of(pos.piece_on(lsb(b)))];
-        }
-
         // Decrease score if we are attacked by an enemy pawn. Remaining part
         // of threat evaluation must be done later when we have full attack info.
         if (ei.attackedBy[Them][PAWN] & s)
@@ -699,8 +687,7 @@ Value do_evaluate(const Position& pos, Value& margin) {
                       & ~ei.attackedBy[Them][0];
 
     if (undefendedMinors)
-        score += more_than_one(undefendedMinors) ? UndefendedMinorPenalty * 2
-                                                 : UndefendedMinorPenalty;
+        score += UndefendedMinorPenalty;
 
     // Enemy pieces not defended by a pawn and under our attack
     weakEnemies =  pos.pieces(Them)

diff --git a/src/search.cpp b/src/search.cpp
index e7fbbcf3dcb3566fc794870fd5b8e05b9fcf5d21..35d1eb5b4a390e0a567793a18e6ba51080295a86 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1343,7 +1343,6 @@ split_point_start: // At split points actual search starts from here
     Bitboard b = (enemies ^ ksq) & newAtt & ~oldAtt;
     while (b)
     {
-        // Note that here we generate illegal "double move"!
         if (futilityBase + PieceValue[EG][pos.piece_on(pop_lsb(&b))] >= beta)
             return true;
     }