Count passed pawns in asymmetry measure

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index a031534d3a4fd9b75d44e8c69ac97f99d8ef9c28..5c33577445dc22e6e1e8a69c4ae9a081e6b77f22 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -2,7 +2,7 @@
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
   Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -43,23 +43,17 @@ namespace {
   // Doubled pawn penalty
   const Score Doubled = S(18, 38);
 
-  // Lever bonus by rank
-  const Score Lever[RANK_NB] = {
-    S( 0,  0), S( 0,  0), S(0, 0), S(0, 0),
-    S(17, 16), S(33, 32), S(0, 0), S(0, 0)
-  };
-
   // Weakness of our pawn shelter in front of the king by [isKingFile][distance from edge][rank].
   // RANK_1 = 0 is used for files where we have no pawns or our pawn is behind our king.
   const Value ShelterWeakness[][int(FILE_NB) / 2][RANK_NB] = {
-    { { V( 97), V(17), V( 9), V(44), V( 84), V( 87), V( 99) }, // Not On King file
-      { V(106), V( 6), V(33), V(86), V( 87), V(104), V(112) },
-      { V(101), V( 2), V(65), V(98), V( 58), V( 89), V(115) },
-      { V( 73), V( 7), V(54), V(73), V( 84), V( 83), V(111) } },
-    { { V(104), V(20), V( 6), V(27), V( 86), V( 93), V( 82) }, // On King file
-      { V(123), V( 9), V(34), V(96), V(112), V( 88), V( 75) },
-      { V(120), V(25), V(65), V(91), V( 66), V( 78), V(117) },
-      { V( 81), V( 2), V(47), V(63), V( 94), V( 93), V(104) } }
+    { { V( 98), V(20), V(11), V(42), V( 83), V( 84), V(101) }, // Not On King file
+      { V(103), V( 8), V(33), V(86), V( 87), V(105), V(113) },
+      { V(100), V( 2), V(65), V(95), V( 59), V( 89), V(115) },
+      { V( 72), V( 6), V(52), V(74), V( 83), V( 84), V(112) } },
+    { { V(105), V(19), V( 3), V(27), V( 85), V( 93), V( 84) }, // On King file
+      { V(121), V( 7), V(33), V(95), V(112), V( 86), V( 72) },
+      { V(121), V(26), V(65), V(90), V( 65), V( 76), V(117) },
+      { V( 79), V( 0), V(45), V(65), V( 94), V( 92), V(105) } }
   };
 
   // Danger of enemy pawns moving toward our king by [type][distance from edge][rank].
@@ -94,10 +88,8 @@ namespace {
   template<Color Us>
   Score evaluate(const Position& pos, Pawns::Entry* e) {
 
-    const Color  Them  = (Us == WHITE ? BLACK      : WHITE);
-    const Square Up    = (Us == WHITE ? NORTH      : SOUTH);
-    const Square Right = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
-    const Square Left  = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
+    const Color     Them = (Us == WHITE ? BLACK : WHITE);
+    const Direction Up   = (Us == WHITE ? NORTH : SOUTH);
 
     Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
     Bitboard lever, leverPush;
@@ -112,7 +104,7 @@ namespace {
     e->passedPawns[Us] = e->pawnAttacksSpan[Us] = e->weakUnopposed[Us] = 0;
     e->semiopenFiles[Us] = 0xFF;
     e->kingSquares[Us]   = SQ_NONE;
-    e->pawnAttacks[Us]   = shift<Right>(ourPawns) | shift<Left>(ourPawns);
+    e->pawnAttacks[Us]   = pawn_attacks_bb<Us>(ourPawns);
     e->pawnsOnSquares[Us][BLACK] = popcount(ourPawns & DarkSquares);
     e->pawnsOnSquares[Us][WHITE] = pos.count<PAWN>(Us) - e->pawnsOnSquares[Us][BLACK];
 
@@ -172,6 +164,9 @@ namespace {
                     e->passedPawns[Us] |= s;
         }
 
+        if (e->passedPawns[Us] & s)
+            e->asymmetry++;
+
         // Score this pawn
         if (supported | phalanx)
             score += Connected[opposed][bool(phalanx)][popcount(supported)][relative_rank(Us, s)];
@@ -184,9 +179,6 @@ namespace {
 
         if (doubled && !supported)
             score -= Doubled;
-
-        if (lever)
-            score += Lever[relative_rank(Us, s)];
     }
 
     return score;
@@ -231,9 +223,12 @@ Entry* probe(const Position& pos) {
       return e;
 
   e->key = key;
-  e->score = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
-  e->asymmetry = popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
-  e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
+  e->asymmetry = 0;
+  e->scores[WHITE] = evaluate<WHITE>(pos, e);
+  e->scores[BLACK] = evaluate<BLACK>(pos, e);
+  e->asymmetry += popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
+  e->openFiles  = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
+
   return e;
 }
 
@@ -254,7 +249,7 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) {
   Value safety = MaxSafetyBonus;
   File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
 
-  for (File f = center - File(1); f <= center + File(1); ++f)
+  for (File f = File(center - 1); f <= File(center + 1); ++f)
   {
       b = ourPawns & file_bb(f);
       Rank rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1;
@@ -262,7 +257,7 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) {
       b = theirPawns & file_bb(f);
       Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
 
-      int d = std::min(f, FILE_H - f);
+      int d = std::min(f, ~f);
       safety -=  ShelterWeakness[f == file_of(ksq)][d][rkUs]
                + StormDanger
                  [f == file_of(ksq) && rkThem == relative_rank(Us, ksq) + 1 ? BlockedByKing  :