/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- // Evaluation weights
- int WeightMobilityMidgame = 0x100;
- int WeightMobilityEndgame = 0x100;
- int WeightPawnStructureMidgame = 0x100;
- int WeightPawnStructureEndgame = 0x100;
- int WeightPassedPawnsMidgame = 0x100;
- int WeightPassedPawnsEndgame = 0x100;
- int WeightKingSafety[2] = { 0x100, 0x100 };
+ // Evaluation weights, initialized from UCI options
+ int WeightMobilityMidgame, WeightMobilityEndgame;
+ int WeightPawnStructureMidgame, WeightPawnStructureEndgame;
+ int WeightPassedPawnsMidgame, WeightPassedPawnsEndgame;
+ int WeightKingSafety[2];
- // Internal evaluation weights. These are applied on top of the evaluation
- // weights read from UCI parameters. The purpose is to be able to change
+ // Internal evaluation weights. These are applied on top of the evaluation
+ // weights read from UCI parameters. The purpose is to be able to change
// the evaluation weights while keeping the default values of the UCI
// parameters at 100, which looks prettier.
//
// the evaluation weights while keeping the default values of the UCI
// parameters at 100, which looks prettier.
//
// Rooks on open files
const Value RookOpenFileBonus = Value(43);
const Value RookHalfOpenFileBonus = Value(19);
// Penalty for rooks trapped inside a friendly king which has lost the
// Rooks on open files
const Value RookOpenFileBonus = Value(43);
const Value RookHalfOpenFileBonus = Value(19);
// Penalty for rooks trapped inside a friendly king which has lost the
const Value TrappedRookPenalty = Value(180);
// Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by
const Value TrappedRookPenalty = Value(180);
// Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by
const Bitboard MaskA7H7[2] = {
((1ULL << SQ_A7) | (1ULL << SQ_H7)),
((1ULL << SQ_A2) | (1ULL << SQ_H2))
};
// Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
const Bitboard MaskA7H7[2] = {
((1ULL << SQ_A7) | (1ULL << SQ_H7)),
((1ULL << SQ_A2) | (1ULL << SQ_H2))
};
// Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
const Bitboard MaskA1H1[2] = {
((1ULL << SQ_A1) | (1ULL << SQ_H1)),
((1ULL << SQ_A8) | (1ULL << SQ_H8))
};
// The SpaceMask[color] contains area of the board which is consdered by
const Bitboard MaskA1H1[2] = {
((1ULL << SQ_A1) | (1ULL << SQ_H1)),
((1ULL << SQ_A8) | (1ULL << SQ_H8))
};
// The SpaceMask[color] contains area of the board which is consdered by
// based on how many squares inside this area are safe and available for
// friendly minor pieces.
const Bitboard SpaceMask[2] = {
// based on how many squares inside this area are safe and available for
// friendly minor pieces.
const Bitboard SpaceMask[2] = {
- /// King safety constants and variables. The king safety scores are taken
- /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
+ /// King safety constants and variables. The king safety scores are taken
+ /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
/// the strength of the attack are added up into an integer, which is used
/// as an index to SafetyTable[].
/// the strength of the attack are added up into an integer, which is used
/// as an index to SafetyTable[].
const int QueenAttackWeight = 5;
const int RookAttackWeight = 3;
const int BishopAttackWeight = 2;
const int KnightAttackWeight = 2;
const int QueenAttackWeight = 5;
const int RookAttackWeight = 3;
const int BishopAttackWeight = 2;
const int KnightAttackWeight = 2;
- // Bonuses for safe checks for each piece type.
- int QueenContactCheckBonus = 3;
- int QueenCheckBonus = 2;
- int RookCheckBonus = 1;
- int BishopCheckBonus = 1;
- int KnightCheckBonus = 1;
- int DiscoveredCheckBonus = 3;
+ // Bonuses for safe checks, initialized from UCI options
+ int QueenContactCheckBonus, DiscoveredCheckBonus;
+ int QueenCheckBonus, RookCheckBonus, BishopCheckBonus, KnightCheckBonus;
15, 15, 15, 15, 15, 15, 15, 15
};
15, 15, 15, 15, 15, 15, 15, 15
};
- PawnInfoTable *PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
- MaterialInfoTable *MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ PawnInfoTable* PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ MaterialInfoTable* MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
// Sizes of pawn and material hash tables
const int PawnTableSize = 16384;
const int MaterialTableSize = 1024;
// Sizes of pawn and material hash tables
const int PawnTableSize = 16384;
const int MaterialTableSize = 1024;
- template<PieceType Piece>
+ template<bool HasPopCnt>
+ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID);
+
+ template<PieceType Piece, bool HasPopCnt>
- void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo &ei);
+ void evaluate_pieces<KING, false>(const Position& p, Color us, EvalInfo &ei);
void evaluate_passed_pawns(const Position &pos, EvalInfo &ei);
void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
void evaluate_passed_pawns(const Position &pos, EvalInfo &ei);
void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
void evaluate_space(const Position &p, Color us, EvalInfo &ei);
inline Value apply_weight(Value v, int w);
void evaluate_space(const Position &p, Color us, EvalInfo &ei);
inline Value apply_weight(Value v, int w);
int compute_weight(int uciWeight, int internalWeight);
int weight_option(const std::string& opt, int weight);
int compute_weight(int uciWeight, int internalWeight);
int weight_option(const std::string& opt, int weight);
/// values, an endgame score and a middle game score, and interpolates
/// between them based on the remaining material.
/// values, an endgame score and a middle game score, and interpolates
/// between them based on the remaining material.
+Value evaluate(const Position& pos, EvalInfo& ei, int threadID) {
+
+ return CpuHasPOPCNT ? do_evaluate<true>(pos, ei, threadID)
+ : do_evaluate<false>(pos, ei, threadID);
+}
+
+namespace {
-Value evaluate(const Position &pos, EvalInfo &ei, int threadID) {
+template<bool HasPopCnt>
+Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) {
// 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);
// 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;
+ ei.kingAttackersCount[WHITE] = count_1s_max_15<HasPopCnt>(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
+ ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
- evaluate_pieces<KNIGHT>(pos, c, ei);
- evaluate_pieces<BISHOP>(pos, c, ei);
- evaluate_pieces<ROOK>(pos, c, ei);
- evaluate_pieces<QUEEN>(pos, c, ei);
+ evaluate_pieces<KNIGHT, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<BISHOP, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<ROOK, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<QUEEN, HasPopCnt>(pos, c, ei);
// Sum up all attacked squares
ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
// Sum up all attacked squares
ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
// because we need complete attack information for all pieces when computing
// the king safety evaluation.
for (Color c = WHITE; c <= BLACK; c++)
// because we need complete attack information for all pieces when computing
// the king safety evaluation.
for (Color c = WHITE; c <= BLACK; c++)
// Evaluate passed pawns. We evaluate passed pawns for both sides at once,
// because we need to know which side promotes first in positions where
// Evaluate passed pawns. We evaluate passed pawns for both sides at once,
// because we need to know which side promotes first in positions where
/// quick_evaluate() does a very approximate evaluation of the current position.
/// It currently considers only material and piece square table scores. Perhaps
/// quick_evaluate() does a very approximate evaluation of the current position.
/// It currently considers only material and piece square table scores. Perhaps
-/// scale_by_game_phase() interpolates between a middle game and an endgame
-/// 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, const ScaleFactor sf[]) {
-
- assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
- assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
- assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
-
- ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
-
- Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
- return Value(int(result) & ~(GrainSize - 1));
-}
-
int evaluate_common(const Position& p, const Bitboard& b, Color us, EvalInfo& ei, Square s = SQ_NONE) {
static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight };
int evaluate_common(const Position& p, const Bitboard& b, Color us, EvalInfo& ei, Square s = SQ_NONE) {
static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight };
- int mob = (Piece != QUEEN ? count_1s_max_15(bb & ~p.pieces_of_color(us))
- : count_1s(bb & ~p.pieces_of_color(us)));
+ int mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(bb & ~p.pieces_of_color(us))
+ : count_1s<HasPopCnt>(bb & ~p.pieces_of_color(us)));
ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
ei.egMobility += Sign[us] * EgBonus[Piece][mob];
// Bishop and Knight outposts
ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
ei.egMobility += Sign[us] * EgBonus[Piece][mob];
// Bishop and Knight outposts
- if ( (Piece != BISHOP && Piece != KNIGHT) // compile time condition
- || !p.square_is_weak(s, them))
- return mob;
-
- // Initial bonus based on square
- Value v, bonus;
- v = bonus = OutpostBonus[Piece][relative_square(us, s)];
-
- // Increase bonus if supported by pawn, especially if the opponent has
- // no minor piece which can exchange the outpost piece
- if (v && (p.pawn_attacks(them, s) & p.pawns(us)))
+ if ( (Piece == BISHOP || Piece == KNIGHT) // compile time condition
+ && p.square_is_weak(s, them))
- bonus += v / 2;
- if ( p.piece_count(them, KNIGHT) == 0
- && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
- bonus += v;
+ // Initial bonus based on square
+ Value v, bonus;
+ v = bonus = OutpostBonus[Piece][relative_square(us, s)];
+
+ // Increase bonus if supported by pawn, especially if the opponent has
+ // no minor piece which can exchange the outpost piece
+ if (v && (p.pawn_attacks(them, s) & p.pawns(us)))
+ {
+ bonus += v / 2;
+ if ( p.piece_count(them, KNIGHT) == 0
+ && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
+ bonus += v;
+ }
+ ei.mgValue += Sign[us] * bonus;
+ ei.egValue += Sign[us] * bonus;
b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us));
// Attacks, mobility and outposts
b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us));
// Attacks, mobility and outposts
- mob = evaluate_common<Piece>(pos, b, us, ei, s);
+ mob = evaluate_common<Piece, HasPopCnt>(pos, b, us, ei, s);
// Special patterns: trapped bishops on a7/h7/a2/h2
// and trapped bishops on a1/h1/a8/h8 in Chess960.
// Special patterns: trapped bishops on a7/h7/a2/h2
// and trapped bishops on a1/h1/a8/h8 in Chess960.
evaluate_trapped_bishop_a1h1(pos, s, us, ei);
}
evaluate_trapped_bishop_a1h1(pos, s, us, ei);
}
- if (Piece != ROOK && Piece != QUEEN)
- continue;
-
- // Queen or rook on 7th rank
- them = opposite_color(us);
-
- if ( relative_rank(us, s) == RANK_7
- && relative_rank(us, pos.king_square(them)) == RANK_8)
+ if (Piece == ROOK || Piece == QUEEN)
- ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
- ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ // Queen or rook on 7th rank
+ them = opposite_color(us);
+
+ if ( relative_rank(us, s) == RANK_7
+ && relative_rank(us, pos.king_square(them)) == RANK_8)
+ {
+ ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
+ ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ }
- ei.mgValue += Sign[us] * RookOpenFileBonus;
- ei.egValue += Sign[us] * RookOpenFileBonus;
- }
- else
- {
- ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
- ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ if (ei.pi->file_is_half_open(them, f))
+ {
+ ei.mgValue += Sign[us] * RookOpenFileBonus;
+ ei.egValue += Sign[us] * RookOpenFileBonus;
+ }
+ else
+ {
+ ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
+ ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ }
- // Penalize rooks which are trapped inside a king. Penalize more if
- // king has lost right to castle.
- if (mob > 6 || ei.pi->file_is_half_open(us, f))
- continue;
+ // Penalize rooks which are trapped inside a king. Penalize more if
+ // king has lost right to castle.
+ if (mob > 6 || ei.pi->file_is_half_open(us, f))
+ continue;
- if ( square_file(ksq) >= FILE_E
- && square_file(s) > square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
- }
- else if ( square_file(ksq) <= FILE_D
- && square_file(s) < square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
+ if ( square_file(ksq) >= FILE_E
+ && square_file(s) > square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
+ else if ( square_file(ksq) <= FILE_D
+ && square_file(s) < square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
- void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo& ei) {
+ void evaluate_pieces<KING, false>(const Position& p, Color us, EvalInfo& ei) {
int shelter = 0, sign = Sign[us];
Square s = p.king_square(us);
int shelter = 0, sign = Sign[us];
Square s = p.king_square(us);
- 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);
-
+ // Shelter cache lookup
+ shelter = ei.pi->kingShelter(us, s);
+ if (shelter == -1)
+ {
+ shelter = 0;
+ Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
+ Rank r = square_rank(s);
+ for (int i = 1; i < 4; i++)
+ shelter += BitCount8Bit[shiftRowsDown(pawns, r+i*sign) & 0xFF] * (128 >> i);
+
+ // Cache shelter value in pawn info
+ ei.pi->setKingShelter(us, s, shelter);
+ }
// quality of the pawn shelter.
int attackUnits =
Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
// quality of the pawn shelter.
int attackUnits =
Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
+ InitKingDanger[relative_square(us, s)] - (shelter >> 5);
// Analyse safe queen contact checks
+ InitKingDanger[relative_square(us, s)] - (shelter >> 5);
// Analyse safe queen contact checks
if ( bit_is_set(p.piece_attacks<QUEEN>(from), to)
&& !bit_is_set(p.pinned_pieces(them), from)
&& !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))
if ( bit_is_set(p.piece_attacks<QUEEN>(from), to)
&& !bit_is_set(p.pinned_pieces(them), from)
&& !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))
- int space = count_1s_max_15(safeSquares)
- + count_1s_max_15(behindFriendlyPawns & safeSquares);
+ int space = count_1s_max_15<false>(safeSquares)
+ + count_1s_max_15<false>(behindFriendlyPawns & safeSquares);
- // count_1s_8bit() counts the number of nonzero bits in the 8 least
- // significant bits of a Bitboard. This function is used by the king
- // shield evaluation.
+ // scale_by_game_phase() interpolates between a middle game and an endgame
+ // 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, const ScaleFactor sf[]) {
+
+ assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
+ assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
+ assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
+
+ ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);