Prefer template to name decoration
[stockfish] / src / evaluate.cpp
index 94e807f5d2aa5afc584b14d424ed4583d7dfd15e..4bda8466e1fdaeddc3e346376d4a37f2a038dbae 100644 (file)
@@ -270,11 +270,12 @@ namespace {
                                     EvalInfo &ei);
 
   inline Value apply_weight(Value v, int w);
-  Value scale_by_game_phase(Value mv, Value ev, Phase ph, ScaleFactor sf[]);
+  Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]);
 
   int count_1s_8bit(Bitboard b);
 
   int compute_weight(int uciWeight, int internalWeight);
+  int weight_option(const std::string& opt, int weight);
   void init_safety();
 
 }
@@ -289,141 +290,122 @@ namespace {
 /// between them based on the remaining material.
 
 Value evaluate(const Position &pos, EvalInfo &ei, int threadID) {
-  Color stm;
-  Square s;
-  ScaleFactor factor[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};
-  Phase phase;
-
-  memset(&ei, 0, sizeof(EvalInfo));
 
   assert(pos.is_ok());
   assert(threadID >= 0 && threadID < THREAD_MAX);
 
-  stm = pos.side_to_move();
+  memset(&ei, 0, sizeof(EvalInfo));
 
   // Initialize by reading the incrementally updated scores included in the
-  // position object (material + piece square tables):
+  // position object (material + piece square tables)
   ei.mgValue = pos.mg_value();
   ei.egValue = pos.eg_value();
 
-  // Probe the material hash table:
+  // Probe the material hash table
   ei.mi = MaterialTable[threadID]->get_material_info(pos);
   ei.mgValue += ei.mi->mg_value();
   ei.egValue += ei.mi->eg_value();
 
-  factor[WHITE] = ei.mi->scale_factor(pos, WHITE);
-  factor[BLACK] = ei.mi->scale_factor(pos, BLACK);
-
   // If we have a specialized evaluation function for the current material
-  // configuration, call it and return:
-  if(ei.mi->specialized_eval_exists())
-    return ei.mi->evaluate(pos);
+  // configuration, call it and return
+  if (ei.mi->specialized_eval_exists())
+      return ei.mi->evaluate(pos);
 
-  phase = pos.game_phase();
+  // After get_material_info() call that modifies them
+  ScaleFactor factor[2];
+  factor[WHITE] = ei.mi->scale_factor(pos, WHITE);
+  factor[BLACK] = ei.mi->scale_factor(pos, BLACK);
 
-  // Probe the pawn hash table:
+  // Probe the pawn hash table
   ei.pi = PawnTable[threadID]->get_pawn_info(pos);
   ei.mgValue += apply_weight(ei.pi->mg_value(), WeightPawnStructureMidgame);
   ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame);
 
-  // Initialize king attack bitboards and king attack zones for both sides:
-  ei.attackedBy[WHITE][KING] = pos.king_attacks(pos.king_square(WHITE));
-  ei.attackedBy[BLACK][KING] = pos.king_attacks(pos.king_square(BLACK));
-  ei.kingZone[WHITE] =
-    ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8);
-  ei.kingZone[BLACK] =
-    ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8);
-
-  // Initialize pawn attack bitboards for both sides:
-  ei.attackedBy[WHITE][PAWN] =
-    ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB);
-  ei.kingAttackersCount[WHITE] +=
-    count_1s_max_15(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
-  ei.attackedBy[BLACK][PAWN] =
-    ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB);
-  ei.kingAttackersCount[BLACK] +=
-    count_1s_max_15(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
-
-  // Evaluate pieces:
-  for(Color c = WHITE; c <= BLACK; c++) {
-    Bitboard b;
+  // Initialize king attack bitboards and king attack zones for both sides
+  ei.attackedBy[WHITE][KING] = pos.piece_attacks<KING>(pos.king_square(WHITE));
+  ei.attackedBy[BLACK][KING] = pos.piece_attacks<KING>(pos.king_square(BLACK));
+  ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8);
+  ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8);
+
+  // Initialize pawn attack bitboards for both sides
+  ei.attackedBy[WHITE][PAWN] = ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB);
+  ei.attackedBy[BLACK][PAWN] = ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB);
+  ei.kingAttackersCount[WHITE] = count_1s_max_15(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
+  ei.kingAttackersCount[BLACK] = count_1s_max_15(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
 
+  // Evaluate pieces
+  for (Color c = WHITE; c <= BLACK; c++)
+  {
     // Knights
-    for(int i = 0; i < pos.knight_count(c); i++) {
-      s = pos.knight_list(c, i);
-      evaluate_knight(pos, s, c, ei);
-    }
+    for (int i = 0; i < pos.knight_count(c); i++)
+        evaluate_knight(pos, pos.knight_list(c, i), c, ei);
 
     // Bishops
-    for(int i = 0; i < pos.bishop_count(c); i++) {
-      s = pos.bishop_list(c, i);
-      evaluate_bishop(pos, s, c, ei);
-    }
+    for (int i = 0; i < pos.bishop_count(c); i++)
+        evaluate_bishop(pos, pos.bishop_list(c, i), c, ei);
 
     // Rooks
-    for(int i = 0; i < pos.rook_count(c); i++) {
-      s = pos.rook_list(c, i);
-      evaluate_rook(pos, s, c, ei);
-    }
+    for (int i = 0; i < pos.rook_count(c); i++)
+        evaluate_rook(pos, pos.rook_list(c, i), c, ei);
 
     // Queens
-    for(int i = 0; i < pos.queen_count(c); i++) {
-      s = pos.queen_list(c, i);
-      evaluate_queen(pos, s, c, ei);
-    }
-
-    // Some special patterns:
+    for(int i = 0; i < pos.queen_count(c); i++)
+        evaluate_queen(pos, pos.queen_list(c, i), c, ei);
 
-    // Trapped bishops on a7/h7/a2/h2
-    b = pos.bishops(c) & MaskA7H7[c];
-    while(b) {
-      s = pop_1st_bit(&b);
-      evaluate_trapped_bishop_a7h7(pos, s, c, ei);
+    // Special pattern: trapped bishops on a7/h7/a2/h2
+    Bitboard b = pos.bishops(c) & MaskA7H7[c];
+    while (b)
+    {
+        Square s = pop_1st_bit(&b);
+        evaluate_trapped_bishop_a7h7(pos, s, c, ei);
     }
 
-    // Trapped bishops on a1/h1/a8/h8 in Chess960:
-    if(Chess960) {
-      b = pos.bishops(c) & MaskA1H1[c];
-      while(b) {
-        s = pop_1st_bit(&b);
-        evaluate_trapped_bishop_a1h1(pos, s, c, ei);
-      }
+    // Special pattern: trapped bishops on a1/h1/a8/h8 in Chess960:
+    if (Chess960)
+    {
+        b = pos.bishops(c) & MaskA1H1[c];
+        while (b)
+        {
+            Square s = pop_1st_bit(&b);
+            evaluate_trapped_bishop_a1h1(pos, s, c, ei);
+        }
     }
 
-    ei.attackedBy[c][0] =
-      ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
-      | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK]
-      | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING];
+    // Sum up all attacked squares
+    ei.attackedBy[c][0] =   ei.attackedBy[c][PAWN]   | ei.attackedBy[c][KNIGHT]
+                          | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK]
+                          | ei.attackedBy[c][QUEEN]  | ei.attackedBy[c][KING];
   }
 
   // Kings.  Kings are evaluated after all other pieces for both sides,
   // because we need complete attack information for all pieces when computing
   // the king safety evaluation.
-  for(Color c = WHITE; c <= BLACK; c++) {
-    s = pos.king_square(c);
-    evaluate_king(pos, s, c, ei);
-  }
+  for (Color c = WHITE; c <= BLACK; c++)
+      evaluate_king(pos, pos.king_square(c), c, ei);
 
   // Evaluate passed pawns.  We evaluate passed pawns for both sides at once,
   // because we need to know which side promotes first in positions where
   // both sides have an unstoppable passed pawn.
-  if(ei.pi->passed_pawns())
-    evaluate_passed_pawns(pos, ei);
+  if (ei.pi->passed_pawns())
+      evaluate_passed_pawns(pos, ei);
 
-  // Middle-game specific evaluation terms
-  if(phase > PHASE_ENDGAME) {
+  Phase phase = pos.game_phase();
 
+  // Middle-game specific evaluation terms
+  if (phase > PHASE_ENDGAME)
+  {
     // Pawn storms in positions with opposite castling.
-    if(square_file(pos.king_square(WHITE)) >= FILE_E &&
-       square_file(pos.king_square(BLACK)) <= FILE_D)
-      ei.mgValue +=
-        ei.pi->queenside_storm_value(WHITE) -
-        ei.pi->kingside_storm_value(BLACK);
-    else if(square_file(pos.king_square(WHITE)) <= FILE_D &&
-            square_file(pos.king_square(BLACK)) >= FILE_E)
-      ei.mgValue +=
-        ei.pi->kingside_storm_value(WHITE) -
-        ei.pi->queenside_storm_value(BLACK);
+    if (   square_file(pos.king_square(WHITE)) >= FILE_E
+        && square_file(pos.king_square(BLACK)) <= FILE_D)
+
+        ei.mgValue += ei.pi->queenside_storm_value(WHITE)
+                    - ei.pi->kingside_storm_value(BLACK);
+
+    else if (   square_file(pos.king_square(WHITE)) <= FILE_D
+             && square_file(pos.king_square(BLACK)) >= FILE_E)
+
+        ei.mgValue += ei.pi->kingside_storm_value(WHITE)
+                    - ei.pi->queenside_storm_value(BLACK);
   }
 
   // Mobility
@@ -432,46 +414,40 @@ Value evaluate(const Position &pos, EvalInfo &ei, int threadID) {
 
   // If we don't already have an unusual scale factor, check for opposite
   // colored bishop endgames, and use a lower scale for those:
-  if(phase < PHASE_MIDGAME && pos.opposite_colored_bishops()
-     && ((factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0)) ||
-         (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0)))) {
-    if(pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) ==
-       2*BishopValueMidgame) {
-      // Only the two bishops
-      if(pos.pawn_count(WHITE) + pos.pawn_count(BLACK) == 1) {
-        // KBP vs KB with only a single pawn; almost certainly a draw.
-        if(factor[WHITE] == SCALE_FACTOR_NORMAL)
-          factor[WHITE] = ScaleFactor(8);
-        if(factor[BLACK] == SCALE_FACTOR_NORMAL)
-          factor[BLACK] = ScaleFactor(8);
-      }
-      else {
-        // At least two pawns
-        if(factor[WHITE] == SCALE_FACTOR_NORMAL)
-          factor[WHITE] = ScaleFactor(32);
-        if(factor[BLACK] == SCALE_FACTOR_NORMAL)
-          factor[BLACK] = ScaleFactor(32);
+  if (   phase < PHASE_MIDGAME
+      && pos.opposite_colored_bishops()
+      && (   (factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0))
+          || (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0))))
+  {
+      ScaleFactor sf;
+
+      // Only the two bishops ?
+      if (   pos.non_pawn_material(WHITE) == BishopValueMidgame
+          && pos.non_pawn_material(BLACK) == BishopValueMidgame)
+      {
+          // Check for KBP vs KB with only a single pawn that is almost
+          // certainly a draw or at least two pawns.
+          bool one_pawn = (pos.pawn_count(WHITE) + pos.pawn_count(BLACK) == 1);
+          sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32);
       }
-    }
-    else {
-      // Endgame with opposite-colored bishops, but also other pieces.
-      // Still a bit drawish, but not as drawish as with only the two
-      // bishops.
-      if(factor[WHITE] == SCALE_FACTOR_NORMAL)
-        factor[WHITE] = ScaleFactor(50);
-      if(factor[BLACK] == SCALE_FACTOR_NORMAL)
-        factor[BLACK] = ScaleFactor(50);
-    }
+      else
+          // Endgame with opposite-colored bishops, but also other pieces. Still
+          // a bit drawish, but not as drawish as with only the two bishops.
+           sf = ScaleFactor(50);
+
+      if (factor[WHITE] == SCALE_FACTOR_NORMAL)
+          factor[WHITE] = sf;
+      if (factor[BLACK] == SCALE_FACTOR_NORMAL)
+          factor[BLACK] = sf;
   }
 
   // Interpolate between the middle game and the endgame score, and
-  // return:
-  Value value = scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor);
+  // return
+  Color stm = pos.side_to_move();
+
+  Value v = Sign[stm] * scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor);
 
-  if(ei.mateThreat[stm] != MOVE_NONE)
-    return 8 * QueenValueMidgame - Sign[stm] * value;
-  else
-    return Sign[stm] * value;
+  return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v);
 }
 
 
@@ -480,22 +456,18 @@ Value evaluate(const Position &pos, EvalInfo &ei, int threadID) {
 /// we should add scores from the pawn and material hash tables?
 
 Value quick_evaluate(const Position &pos) {
-  Color stm;
-  Value mgValue, egValue;
-  ScaleFactor factor[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};
-  Phase phase;
 
   assert(pos.is_ok());
 
-  stm = pos.side_to_move();
-
-  mgValue = pos.mg_value();
-  egValue = pos.eg_value();
-  phase = pos.game_phase();
+  static const
+  ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};  
 
-  Value value = scale_by_game_phase(mgValue, egValue, phase, factor);
+  Value mgv = pos.mg_value();
+  Value egv = pos.eg_value();
+  Phase ph = pos.game_phase();
+  Color stm = pos.side_to_move();
 
-  return Sign[stm] * value;
+  return Sign[stm] * scale_by_game_phase(mgv, egv, ph, sf);
 }
 
 
@@ -529,9 +501,11 @@ void init_eval(int threads) {
 /// quit_eval() releases heap-allocated memory at program termination.
 
 void quit_eval() {
-  for(int i = 0; i < THREAD_MAX; i++) {
-    delete PawnTable[i];
-    delete MaterialTable[i];
+
+  for (int i = 0; i < THREAD_MAX; i++)
+  {
+      delete PawnTable[i];
+      delete MaterialTable[i];
   }
 }
 
@@ -539,11 +513,6 @@ void quit_eval() {
 /// read_weights() reads evaluation weights from the corresponding UCI
 /// parameters.
 
-int weight_option(const std::string& opt, int weight) {
-
-    return compute_weight(get_option_value_int(opt), weight);
-}
-
 void read_weights(Color us) {
 
   WeightMobilityMidgame      = weight_option("Mobility (Middle Game)", WeightMobilityMidgameInternal);
@@ -575,11 +544,11 @@ namespace {
     // King attack
     if (b & ei.kingZone[us])
     {
-      ei.kingAttackersCount[us]++;
-      ei.kingAttackersWeight[us] += AttackWeight;
-      Bitboard bb = (b & ei.attackedBy[them][KING]);
-      if (bb)
-          ei.kingZoneAttacksCount[us] += count_1s_max_15(bb);
+        ei.kingAttackersCount[us]++;
+        ei.kingAttackersWeight[us] += AttackWeight;
+        Bitboard bb = (b & ei.attackedBy[them][KING]);
+        if (bb)
+            ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15(bb);
     }
 
     // Mobility
@@ -615,7 +584,7 @@ namespace {
 
   void evaluate_knight(const Position &p, Square s, Color us, EvalInfo &ei) {
 
-    Bitboard b = p.knight_attacks(s);
+    Bitboard b = p.piece_attacks<KNIGHT>(s);
     ei.attackedBy[us][KNIGHT] |= b;
 
     // King attack, mobility and outposts
@@ -681,7 +650,7 @@ namespace {
     // king has lost right to castle
     if (mob > 6 || ei.pi->file_is_half_open(us, f))
         return;
-    
+
     Square ksq = p.king_square(us);
 
     if (    square_file(ksq) >= FILE_E
@@ -710,7 +679,7 @@ namespace {
 
   void evaluate_queen(const Position &p, Square s, Color us, EvalInfo &ei) {
 
-    Bitboard b = p.queen_attacks(s);
+    Bitboard b = p.piece_attacks<QUEEN>(s);
     ei.attackedBy[us][QUEEN] |= b;
 
     // King attack and mobility
@@ -728,6 +697,10 @@ namespace {
     }
   }
 
+  inline Bitboard shiftRowsDown(const Bitboard& b, int num) {
+
+    return b >> (num << 3);
+  }
 
   // evaluate_king() assigns bonuses and penalties to a king of a given
   // color on a given square.
@@ -736,32 +709,37 @@ namespace {
 
     int shelter = 0, sign = Sign[us];
 
-    // King shelter.
-    if(relative_rank(us, s) <= RANK_4) {
-      Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
-      Rank r = square_rank(s);
-      for(int i = 0; i < 3; i++)
-        shelter += count_1s_8bit(pawns >> ((r+(i+1)*sign) * 8)) * (64>>i);
-      ei.mgValue += sign * Value(shelter);
+    // King shelter
+    if (relative_rank(us, s) <= RANK_4)
+    {
+        Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
+        Rank r = square_rank(s);
+        for (int i = 1; i < 4; i++)
+            shelter += count_1s_8bit(shiftRowsDown(pawns, r+i*sign)) * (128>>i);
+
+        ei.mgValue += sign * Value(shelter);
     }
 
     // King safety.  This is quite complicated, and is almost certainly far
     // from optimally tuned.
     Color them = opposite_color(us);
-    if(p.queen_count(them) >= 1 && ei.kingAttackersCount[them] >= 2
-       && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame
-       && ei.kingZoneAttacksCount[them]) {
 
+    if (   p.queen_count(them) >= 1
+        && ei.kingAttackersCount[them] >= 2
+        && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame
+        && ei.kingAdjacentZoneAttacksCount[them])
+    {
       // Is it the attackers turn to move?
       bool sente = (them == p.side_to_move());
 
       // Find the attacked squares around the king which has no defenders
-      // apart from the king itself:
+      // apart from the king itself
       Bitboard undefended =
-        ei.attacked_by(them) & ~ei.attacked_by(us, PAWN)
-        & ~ei.attacked_by(us, KNIGHT) & ~ei.attacked_by(us, BISHOP)
-        & ~ei.attacked_by(us, ROOK) & ~ei.attacked_by(us, QUEEN)
-        & ei.attacked_by(us, KING);
+             ei.attacked_by(them)       & ~ei.attacked_by(us, PAWN)
+          & ~ei.attacked_by(us, KNIGHT) & ~ei.attacked_by(us, BISHOP)
+          & ~ei.attacked_by(us, ROOK)   & ~ei.attacked_by(us, QUEEN)
+          & ei.attacked_by(us, KING);
+
       Bitboard occ = p.occupied_squares(), b, b2;
 
       // Initialize the 'attackUnits' variable, which is used later on as an
@@ -770,113 +748,134 @@ namespace {
       // undefended squares around the king, the square of the king, and the
       // quality of the pawn shelter.
       int attackUnits =
-        Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
-        + (ei.kingZoneAttacksCount[them] + count_1s_max_15(undefended)) * 3
-        + InitKingDanger[relative_square(us, s)] - shelter / 32;
+            Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
+          + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15(undefended)) * 3
+          + InitKingDanger[relative_square(us, s)] - shelter / 32;
 
-      // Analyse safe queen contact checks:
+      // Analyse safe queen contact checks
       b = undefended & ei.attacked_by(them, QUEEN) & ~p.pieces_of_color(them);
-      if(b) {
+      if (b)
+      {
         Bitboard attackedByOthers =
-          ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT)
-          | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK);
+              ei.attacked_by(them, PAWN)   | ei.attacked_by(them, KNIGHT)
+            | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK);
+
         b &= attackedByOthers;
-        if(b) {
+        if (b)
+        {
           // The bitboard b now contains the squares available for safe queen
           // contact checks.
           int count = count_1s_max_15(b);
-          attackUnits += QueenContactCheckBonus * count * (sente? 2 : 1);
+          attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1);
 
           // Is there a mate threat?
-          if(QueenContactMates && !p.is_check()) {
+          if (QueenContactMates && !p.is_check())
+          {
             Bitboard escapeSquares =
-              p.king_attacks(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
-            while(b) {
-              Square from, to = pop_1st_bit(&b);
-              if(!(escapeSquares
-                   & ~queen_attacks_bb(to, occ & clear_mask_bb(s)))) {
-                // We have a mate, unless the queen is pinned or there
-                // is an X-ray attack through the queen.
-                for(int i = 0; i < p.queen_count(them); i++) {
-                  from = p.queen_list(them, i);
-                  if(bit_is_set(p.queen_attacks(from), to)
-                     && !bit_is_set(p.pinned_pieces(them), from)
-                     && !(rook_attacks_bb(to, occ & clear_mask_bb(from))
-                          & p.rooks_and_queens(us))
-                     && !(rook_attacks_bb(to, occ & clear_mask_bb(from))
-                          & p.rooks_and_queens(us)))
-                    ei.mateThreat[them] = make_move(from, to);
+                p.piece_attacks<KING>(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
+
+            while (b)
+            {
+                Square from, to = pop_1st_bit(&b);
+                if (!(escapeSquares & ~queen_attacks_bb(to, occ & clear_mask_bb(s))))
+                {
+                    // We have a mate, unless the queen is pinned or there
+                    // is an X-ray attack through the queen.
+                    for (int i = 0; i < p.queen_count(them); i++)
+                    {
+                        from = p.queen_list(them, i);
+                        if (    bit_is_set(p.piece_attacks<QUEEN>(from), to)
+                            && !bit_is_set(p.pinned_pieces(them), from)
+                            && !(rook_attacks_bb(to, occ & clear_mask_bb(from)) & p.rooks_and_queens(us))
+                            && !(rook_attacks_bb(to, occ & clear_mask_bb(from)) & p.rooks_and_queens(us)))
+                            
+                            ei.mateThreat[them] = make_move(from, to);
+                    }
                 }
-              }
             }
           }
         }
       }
-
       // Analyse safe rook contact checks:
-      if(RookContactCheckBonus) {
-        b = undefended & ei.attacked_by(them, ROOK) & ~p.pieces_of_color(them);
-        if(b) {
-          Bitboard attackedByOthers =
-            ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT)
-            | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, QUEEN);
-          b &= attackedByOthers;
-          if(b) {
-            int count = count_1s_max_15(b);
-            attackUnits += (RookContactCheckBonus * count * (sente? 2 : 1));
+      if (RookContactCheckBonus)
+      {
+          b = undefended & ei.attacked_by(them, ROOK) & ~p.pieces_of_color(them);
+          if (b)
+          {
+              Bitboard attackedByOthers =
+                    ei.attacked_by(them, PAWN)   | ei.attacked_by(them, KNIGHT)
+                  | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, QUEEN);
+
+              b &= attackedByOthers;
+              if (b)
+              {
+                  int count = count_1s_max_15(b);
+                  attackUnits += (RookContactCheckBonus * count * (sente? 2 : 1));
+              }
           }
-        }
       }
-
       // Analyse safe distance checks:
-      if(QueenCheckBonus > 0 || RookCheckBonus > 0) {
-        b = p.rook_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
-
-        // Queen checks
-        b2 = b & ei.attacked_by(them, QUEEN);
-        if(b2) attackUnits += QueenCheckBonus * count_1s_max_15(b2);
-
-        // Rook checks
-        b2 = b & ei.attacked_by(them, ROOK);
-        if(b2) attackUnits += RookCheckBonus * count_1s_max_15(b2);
+      if (QueenCheckBonus > 0 || RookCheckBonus > 0)
+      {
+          b = p.piece_attacks<ROOK>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+
+          // Queen checks
+          b2 = b & ei.attacked_by(them, QUEEN);
+          if( b2)
+              attackUnits += QueenCheckBonus * count_1s_max_15(b2);
+
+          // Rook checks
+          b2 = b & ei.attacked_by(them, ROOK);
+          if (b2)
+              attackUnits += RookCheckBonus * count_1s_max_15(b2);
       }
-      if(QueenCheckBonus > 0 || BishopCheckBonus > 0) {
-        b = p.bishop_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
-        // Queen checks
-        b2 = b & ei.attacked_by(them, QUEEN);
-        if(b2) attackUnits += QueenCheckBonus * count_1s_max_15(b2);
-
-        // Bishop checks
-        b2 = b & ei.attacked_by(them, BISHOP);
-        if(b2) attackUnits += BishopCheckBonus * count_1s_max_15(b2);
+      if (QueenCheckBonus > 0 || BishopCheckBonus > 0)
+      {
+          b = p.piece_attacks<BISHOP>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+
+          // Queen checks
+          b2 = b & ei.attacked_by(them, QUEEN);
+          if (b2)
+              attackUnits += QueenCheckBonus * count_1s_max_15(b2);
+
+          // Bishop checks
+          b2 = b & ei.attacked_by(them, BISHOP);
+          if (b2)
+              attackUnits += BishopCheckBonus * count_1s_max_15(b2);
       }
-      if(KnightCheckBonus > 0) {
-        b = p.knight_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
-        // Knight checks
-        b2 = b & ei.attacked_by(them, KNIGHT);
-        if(b2) attackUnits += KnightCheckBonus * count_1s_max_15(b2);
+      if (KnightCheckBonus > 0)
+      {
+          b = p.piece_attacks<KNIGHT>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+
+          // Knight checks
+          b2 = b & ei.attacked_by(them, KNIGHT);
+          if (b2)
+              attackUnits += KnightCheckBonus * count_1s_max_15(b2);
       }
 
       // Analyse discovered checks (only for non-pawns right now, consider
       // adding pawns later).
-      if(DiscoveredCheckBonus) {
+      if (DiscoveredCheckBonus)
+      {
         b = p.discovered_check_candidates(them) & ~p.pawns();
-        if(b)
-          attackUnits +=
-            DiscoveredCheckBonus * count_1s_max_15(b) * (sente? 2 : 1);
+        if (b)
+          attackUnits += DiscoveredCheckBonus * count_1s_max_15(b) * (sente? 2 : 1);
       }
 
       // Has a mate threat been found?  We don't do anything here if the
       // side with the mating move is the side to move, because in that
       // case the mating side will get a huge bonus at the end of the main
       // evaluation function instead.
-      if(ei.mateThreat[them] != MOVE_NONE)
-        attackUnits += MateThreatBonus;
+      if (ei.mateThreat[them] != MOVE_NONE)
+          attackUnits += MateThreatBonus;
 
       // Ensure that attackUnits is between 0 and 99, in order to avoid array
       // out of bounds errors:
-      if(attackUnits < 0) attackUnits = 0;
-      if(attackUnits >= 100) attackUnits = 99;
+      if (attackUnits < 0)
+          attackUnits = 0;
+
+      if (attackUnits >= 100)
+          attackUnits = 99;
 
       // Finally, extract the king safety score from the SafetyTable[] array.
       // Add the score to the evaluation, and also to ei.futilityMargin.  The
@@ -885,9 +884,11 @@ namespace {
       // capturing a single attacking piece can therefore result in a score
       // change far bigger than the value of the captured piece.
       Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[us]);
+
       ei.mgValue -= sign * v;
-      if(us == p.side_to_move())
-        ei.futilityMargin += v;
+
+      if (us == p.side_to_move())
+          ei.futilityMargin += v;
     }
   }
 
@@ -1110,7 +1111,7 @@ namespace {
   // score, based on game phase.  It also scales the return value by a
   // ScaleFactor array.
 
-  Value scale_by_game_phase(Value mv, Value ev, Phase ph, ScaleFactor sf[]) {
+  Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) {
 
     assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
     assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
@@ -1147,6 +1148,13 @@ namespace {
   }
 
 
+  // helper used in read_weights()
+  int weight_option(const std::string& opt, int weight) {
+
+    return compute_weight(get_option_value_int(opt), weight);
+  }
+
+
   // init_safety() initizes the king safety evaluation, based on UCI
   // parameters.  It is called from read_weights().