X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=86b37e3b045a63ae92ebe1b962d132f770b55555;hp=479deb9fe084bcdb0b50184ac1ab43004bf374f2;hb=6738b65be97af10e4b5b783dc8ad21ae0faf36a8;hpb=6c0b2f50032da8e4df0013177d6bb7e1bb1fae8e diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 479deb9f..86b37e3b 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -23,13 +23,14 @@ //// #include -#include +#include +#include +#include #include "bitcount.h" #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "scale.h" #include "thread.h" #include "ucioption.h" @@ -40,7 +41,44 @@ namespace { - const int Sign[2] = { 1, -1 }; + // Struct EvalInfo contains various information computed and collected + // by the evaluation functions. + struct EvalInfo { + + // Pointer to pawn hash table entry + PawnInfo* pi; + + // attackedBy[color][piece type] is a bitboard representing all squares + // attacked by a given color and piece type, attackedBy[color][0] contains + // all squares attacked by the given color. + Bitboard attackedBy[2][8]; + + // kingZone[color] is the zone around the enemy king which is considered + // by the king safety evaluation. This consists of the squares directly + // adjacent to the king, and the three (or two, for a king on an edge file) + // squares two ranks in front of the king. For instance, if black's king + // is on g8, kingZone[WHITE] is a bitboard containing the squares f8, h8, + // f7, g7, h7, f6, g6 and h6. + Bitboard kingZone[2]; + + // kingAttackersCount[color] is the number of pieces of the given color + // which attack a square in the kingZone of the enemy king. + int kingAttackersCount[2]; + + // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the + // given color which attack a square in the kingZone of the enemy king. The + // weights of the individual piece types are given by the variables + // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and + // KnightAttackWeight in evaluate.cpp + int kingAttackersWeight[2]; + + // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares + // directly adjacent to the king of the given color. Pieces which attack + // more than one square are counted multiple times. For instance, if black's + // king is on g8 and there's a white knight on g5, this knight adds + // 2 to kingAdjacentZoneAttacksCount[BLACK]. + int kingAdjacentZoneAttacksCount[2]; + }; // Evaluation grain size, must be a power of 2 const int GrainSize = 8; @@ -62,77 +100,50 @@ namespace { S(248, 271), S(233, 201), S(252, 259), S(46, 0), S(247, 0), S(259, 0) }; - // Knight mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly piecess. - const Score KnightMobilityBonus[16] = { - S(-38,-33), S(-25,-23), S(-12,-13), S( 0,-3), - S( 12, 7), S( 25, 17), S( 31, 22), S(38, 27), S(38, 27) - }; - - // Bishop mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. X-ray attacks through - // queens are also included. - const Score BishopMobilityBonus[16] = { - S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12), - S( 31, 26), S( 45, 40), S(57, 52), S(65, 60), - S( 71, 65), S( 74, 69), S(76, 71), S(78, 73), - S( 79, 74), S( 80, 75), S(81, 76), S(81, 76) - }; - - // Rook mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. X-ray attacks through - // queens and rooks are also included. - const Score RookMobilityBonus[16] = { - S(-20,-36), S(-14,-19), S(-8, -3), S(-2, 13), - S( 4, 29), S( 10, 46), S(14, 62), S(19, 79), - S( 23, 95), S( 26,106), S(27,111), S(28,114), - S( 29,116), S( 30,117), S(31,118), S(32,118) - }; - - // Queen mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. - const Score QueenMobilityBonus[32] = { - S(-10,-18), S(-8,-13), S(-6, -7), S(-3, -2), S(-1, 3), S( 1, 8), - S( 3, 13), S( 5, 19), S( 8, 23), S(10, 27), S(12, 32), S(15, 34), - S( 16, 35), S(17, 35), S(18, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35) - }; - - // Pointers table to access mobility tables through piece type - const Score* MobilityBonus[8] = { 0, 0, KnightMobilityBonus, BishopMobilityBonus, - RookMobilityBonus, QueenMobilityBonus, 0, 0 }; - - // Outpost bonuses for knights and bishops, indexed by square (from white's - // point of view). - const Value KnightOutpostBonus[64] = { - // A B C D E F G H - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 1 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2 - V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), // 3 - V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), // 4 - V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), // 5 - V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0), // 6 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8 + // MobilityBonus[PieceType][attacked] contains mobility bonuses for middle and + // end game, indexed by piece type and number of attacked squares not occupied + // by friendly pieces. + const Score MobilityBonus[][32] = { + {}, {}, + { S(-38,-33), S(-25,-23), S(-12,-13), S( 0, -3), S(12, 7), S(25, 17), // Knights + S( 31, 22), S( 38, 27), S( 38, 27) }, + { S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12), S(31, 26), S(45, 40), // Bishops + S( 57, 52), S( 65, 60), S( 71, 65), S(74, 69), S(76, 71), S(78, 73), + S( 79, 74), S( 80, 75), S( 81, 76), S(81, 76) }, + { S(-20,-36), S(-14,-19), S( -8, -3), S(-2, 13), S( 4, 29), S(10, 46), // Rooks + S( 14, 62), S( 19, 79), S( 23, 95), S(26,106), S(27,111), S(28,114), + S( 29,116), S( 30,117), S( 31,118), S(32,118) }, + { S(-10,-18), S( -8,-13), S( -6, -7), S(-3, -2), S(-1, 3), S( 1, 8), // Queens + S( 3, 13), S( 5, 19), S( 8, 23), S(10, 27), S(12, 32), S(15, 34), + S( 16, 35), S( 17, 35), S( 18, 35), S(20, 35), S(20, 35), S(20, 35), + S( 20, 35), S( 20, 35), S( 20, 35), S(20, 35), S(20, 35), S(20, 35), + S( 20, 35), S( 20, 35), S( 20, 35), S(20, 35), S(20, 35), S(20, 35), + S( 20, 35), S( 20, 35) } }; - const Value BishopOutpostBonus[64] = { + // OutpostBonus[PieceType][Square] contains outpost bonuses of knights and + // bishops, indexed by piece type and square (from white's point of view). + const Value OutpostBonus[][64] = { + { // A B C D E F G H - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 1 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2 - V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), // 3 - V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), // 4 - V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), // 5 - V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0), // 6 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8 + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), + V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), + V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), + V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), + V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0) }, + { + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Bishops + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), + V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), + V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), + V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), + V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) } }; - // ThreatBonus[attacking][attacked] contains bonus according to which - // piece type attacks which one. - const Score ThreatBonus[8][8] = { + // ThreatBonus[attacking][attacked] contains threat bonuses according to + // which piece type attacks which one. + const Score ThreatBonus[][8] = { {}, {}, { S(0, 0), S( 7, 39), S( 0, 0), S(24, 49), S(41,100), S(41,100) }, // KNIGHT { S(0, 0), S( 7, 39), S(24, 49), S( 0, 0), S(41,100), S(41,100) }, // BISHOP @@ -140,17 +151,14 @@ namespace { { S(0, 0), S(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN }; - // ThreatedByPawnPenalty[] contains a penalty according to which piece - // type is attacked by an enemy pawn. - const Score ThreatedByPawnPenalty[8] = { + // ThreatedByPawnPenalty[PieceType] contains a penalty according to which + // piece type is attacked by an enemy pawn. + const Score ThreatedByPawnPenalty[] = { S(0, 0), S(0, 0), S(56, 70), S(56, 70), S(76, 99), S(86, 118) }; #undef S - // Bonus for unstoppable passed pawns - const Value UnstoppablePawnValue = Value(0x500); - // Rooks and queens on the 7th rank (modified by Joona Kiiski) const Score RookOn7thBonus = make_score(47, 98); const Score QueenOn7thBonus = make_score(27, 54); @@ -163,59 +171,43 @@ namespace { // right to castle. const Value TrappedRookPenalty = Value(180); - // Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by - // enemy pawns. - const Score TrappedBishopA7H7Penalty = make_score(300, 300); - - // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black) - 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 // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only // happen in Chess960 games. const Score TrappedBishopA1H1Penalty = make_score(100, 100); - // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black) - const Bitboard MaskA1H1[2] = { - ((1ULL << SQ_A1) | (1ULL << SQ_H1)), - ((1ULL << SQ_A8) | (1ULL << SQ_H8)) - }; - - // The SpaceMask[color] contains the area of the board which is considered + // The SpaceMask[Color] contains the area of the board which is considered // by the space evaluation. In the middle game, each side is given a bonus // based on how many squares inside this area are safe and available for // friendly minor pieces. - const Bitboard SpaceMask[2] = { - (1ULL< - Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID); + template + Value do_evaluate(const Position& pos, Value& margin); template - void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei); + void init_eval_info(const Position& pos, EvalInfo& ei); - template - void evaluate_king(const Position& pos, EvalInfo& ei); + template + Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility); + + template + Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]); template - void evaluate_threats(const Position& pos, EvalInfo& ei); + Score evaluate_threats(const Position& pos, EvalInfo& ei); template - void evaluate_space(const Position& pos, EvalInfo& ei); + int evaluate_space(const Position& pos, EvalInfo& ei); template - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei); + Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei); + + template + Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei); - void evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei); - void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, EvalInfo& ei); - void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei); inline Score apply_weight(Score v, Score weight); - Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]); + Value scale_by_game_phase(const Score& v, Phase ph, ScaleFactor sf); Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight); void init_safety(); } -//// -//// Functions -//// +/// prefetchTables() is called in do_move() to prefetch pawn and material +/// hash tables data that will be needed shortly after in evaluation. + +void prefetchTables(Key pKey, Key mKey, int threadID) { + + PawnTable[threadID]->prefetch(pKey); + MaterialTable[threadID]->prefetch(mKey); +} + /// evaluate() is the main evaluation function. It always computes two /// 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) { +Value evaluate(const Position& pos, Value& margin) { - return CpuHasPOPCNT ? do_evaluate(pos, ei, threadID) - : do_evaluate(pos, ei, threadID); + return CpuHasPOPCNT ? do_evaluate(pos, margin) + : do_evaluate(pos, margin); } namespace { -template -Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { +double to_cp(Value v) { return double(v) / double(PawnValueMidgame); } + +void trace_add(int idx, Score term_w, Score term_b = Score(0)) { + + TracedTerms[WHITE][idx] = term_w; + TracedTerms[BLACK][idx] = term_b; +} + +template +Value do_evaluate(const Position& pos, Value& margin) { - Bitboard b; - ScaleFactor factor[2]; + EvalInfo ei; + Value margins[2]; + Score mobilityWhite, mobilityBlack; assert(pos.is_ok()); - assert(threadID >= 0 && threadID < MAX_THREADS); + assert(pos.thread() >= 0 && pos.thread() < MAX_THREADS); assert(!pos.is_check()); - memset(&ei, 0, sizeof(EvalInfo)); + // Initialize value by reading the incrementally updated scores included + // in the position object (material + piece square tables). + Score bonus = pos.value(); - // Initialize by reading the incrementally updated scores included in the - // position object (material + piece square tables) - ei.value = pos.value(); + // margins[] store the uncertainty estimation of position's evaluation + // that typically is used by the search for pruning decisions. + margins[WHITE] = margins[BLACK] = VALUE_ZERO; // Probe the material hash table - ei.mi = MaterialTable[threadID]->get_material_info(pos); - ei.value += ei.mi->material_value(); + MaterialInfo* mi = MaterialTable[pos.thread()]->get_material_info(pos); + bonus += mi->material_value(); // 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); - - // After get_material_info() call that modifies them - factor[WHITE] = ei.mi->scale_factor(pos, WHITE); - factor[BLACK] = ei.mi->scale_factor(pos, BLACK); + // configuration, call it and return. + if (mi->specialized_eval_exists()) + { + margin = VALUE_ZERO; + return mi->evaluate(pos); + } // Probe the pawn hash table - ei.pi = PawnTable[threadID]->get_pawn_info(pos); - ei.value += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); - - // Initialize king attack bitboards and king attack zones for both sides - ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.king_square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.attacks_from(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] = ei.pi->pawn_attacks(WHITE); - b = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING]; - if (b) - ei.kingAttackersCount[WHITE] = count_1s_max_15(b)/2; - - ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK); - b = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING]; - if (b) - ei.kingAttackersCount[BLACK] = count_1s_max_15(b)/2; - - // Evaluate pieces - evaluate_pieces_of_color(pos, ei); - evaluate_pieces_of_color(pos, ei); - - // 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. - evaluate_king(pos, ei); - evaluate_king(pos, ei); - - // Evaluate tactical threats, we need full attack info including king - evaluate_threats(pos, ei); - evaluate_threats(pos, ei); - - // Evaluate passed pawns, we need full attack info including king - evaluate_passed_pawns(pos, ei); - evaluate_passed_pawns(pos, ei); - - // If one side has only a king, check whether exsists any unstoppable passed pawn - if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK)) - evaluate_unstoppable_pawns(pos, ei); + ei.pi = PawnTable[pos.thread()]->get_pawn_info(pos); + bonus += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); - Phase phase = ei.mi->game_phase(); + // Initialize attack and king safety bitboards + init_eval_info(pos, ei); + init_eval_info(pos, ei); - // 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) + // Evaluate pieces and mobility + bonus += evaluate_pieces_of_color(pos, ei, mobilityWhite) + - evaluate_pieces_of_color(pos, ei, mobilityBlack); - ei.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0); + bonus += apply_weight(mobilityWhite - mobilityBlack, Weights[Mobility]); - else if ( square_file(pos.king_square(WHITE)) <= FILE_D - && square_file(pos.king_square(BLACK)) >= FILE_E) + // Evaluate kings after all other pieces because we need complete attack + // information when computing the king safety evaluation. + bonus += evaluate_king(pos, ei, margins) + - evaluate_king(pos, ei, margins); - ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0); + // Evaluate tactical threats, we need full attack information including king + bonus += evaluate_threats(pos, ei) + - evaluate_threats(pos, ei); - // Evaluate space for both sides - if (ei.mi->space_weight() > 0) - { - evaluate_space(pos, ei); - evaluate_space(pos, ei); - } + // Evaluate passed pawns, we need full attack information including king + bonus += evaluate_passed_pawns(pos, ei) + - evaluate_passed_pawns(pos, ei); + + // If one side has only a king, check whether exists any unstoppable passed pawn + if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK)) + { + bonus += evaluate_unstoppable_pawns(pos, ei); + + if (Trace) + trace_add(UNSTOPPABLE, evaluate_unstoppable_pawns(pos, ei)); } - // Mobility - ei.value += apply_weight(ei.mobility, Weights[Mobility]); + // Evaluate space for both sides, only in middle-game. + if (mi->space_weight()) + { + int s_w = evaluate_space(pos, ei); + int s_b = evaluate_space(pos, ei); + bonus += apply_weight(make_score((s_w - s_b) * mi->space_weight(), 0), Weights[Space]); + + if (Trace) + trace_add(SPACE, apply_weight(make_score(s_w * mi->space_weight(), make_score(0, 0)), Weights[Space]), + apply_weight(make_score(s_b * mi->space_weight(), make_score(0, 0)), Weights[Space])); + } + + // Scale winning side if position is more drawish that what it appears + ScaleFactor sf = eg_value(bonus) > VALUE_DRAW ? mi->scale_factor(pos, WHITE) + : mi->scale_factor(pos, BLACK); + Phase phase = mi->game_phase(); // If we don't already have an unusual scale factor, check for opposite - // colored bishop endgames, and use a lower scale for those + // colored bishop endgames, and use a lower scale for those. if ( phase < PHASE_MIDGAME && pos.opposite_colored_bishops() - && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && eg_value(ei.value) > Value(0)) - || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(ei.value) < Value(0)))) + && sf == SCALE_FACTOR_NORMAL) { - ScaleFactor sf; - // Only the two bishops ? if ( pos.non_pawn_material(WHITE) == BishopValueMidgame && pos.non_pawn_material(BLACK) == BishopValueMidgame) @@ -403,19 +401,36 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // 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 - return Sign[pos.side_to_move()] * scale_by_game_phase(ei.value, phase, factor); + margin = margins[pos.side_to_move()]; + Value v = scale_by_game_phase(bonus, phase, sf); + + if (Trace) + { + trace_add(PST, pos.value()); + trace_add(IMBALANCE, mi->material_value()); + trace_add(PAWN, apply_weight(ei.pi->pawns_value(), Weights[PawnStructure])); + trace_add(MOBILITY, apply_weight(mobilityWhite, Weights[Mobility]), apply_weight(mobilityBlack, Weights[Mobility])); + trace_add(THREAT, evaluate_threats(pos, ei), evaluate_threats(pos, ei)); + trace_add(PASSED, evaluate_passed_pawns(pos, ei), evaluate_passed_pawns(pos, ei)); + trace_add(TOTAL, bonus); + TraceStream << "\nUncertainty margin: White: " << to_cp(margins[WHITE]) + << ", Black: " << to_cp(margins[BLACK]) + << "\nScaling: " << std::noshowpos + << std::setw(6) << 100.0 * phase/128.0 << "% MG, " + << std::setw(6) << 100.0 * (1.0 - phase/128.0) << "% * " + << std::setw(6) << (100.0 * sf) / SCALE_FACTOR_NORMAL << "% EG.\n" + << "Total evaluation: " << to_cp(v); + } + + return pos.side_to_move() == WHITE ? v : -v; } } // namespace + /// init_eval() initializes various tables used by the evaluation function void init_eval(int threads) { @@ -424,18 +439,19 @@ void init_eval(int threads) { for (int i = 0; i < MAX_THREADS; i++) { - if (i >= threads) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - continue; - } - if (!PawnTable[i]) - PawnTable[i] = new PawnInfoTable(PawnTableSize); - if (!MaterialTable[i]) - MaterialTable[i] = new MaterialInfoTable(MaterialTableSize); + if (i >= threads) + { + delete PawnTable[i]; + delete MaterialTable[i]; + PawnTable[i] = NULL; + MaterialTable[i] = NULL; + continue; + } + if (!PawnTable[i]) + PawnTable[i] = new PawnInfoTable(); + + if (!MaterialTable[i]) + MaterialTable[i] = new MaterialInfoTable(); } } @@ -444,19 +460,13 @@ void init_eval(int threads) { void quit_eval() { - for (int i = 0; i < MAX_THREADS; i++) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - } + init_eval(0); } /// read_weights() reads evaluation weights from the corresponding UCI parameters -void read_weights(Color us) { +void read_evaluation_uci_options(Color us) { // King safety is asymmetrical. Our king danger level is weighted by // "Cowardice" UCI parameter, instead the opponent one by "Aggressiveness". @@ -472,7 +482,7 @@ void read_weights(Color us) { // If running in analysis mode, make sure we use symmetrical king safety. We do this // by replacing both Weights[kingDangerUs] and Weights[kingDangerThem] by their average. - if (get_option_value_bool("UCI_AnalyseMode")) + if (Options["UCI_AnalyseMode"].value()) Weights[kingDangerUs] = Weights[kingDangerThem] = (Weights[kingDangerUs] + Weights[kingDangerThem]) / 2; init_safety(); @@ -481,19 +491,45 @@ void read_weights(Color us) { namespace { + // init_eval_info() initializes king bitboards for given color adding + // pawn attacks. To be done at the beginning of the evaluation. + + template + void init_eval_info(const Position& pos, EvalInfo& ei) { + + const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; + const Color Them = (Us == WHITE ? BLACK : WHITE); + + Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.king_square(Them)); + ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); + + // Init king safety tables only if we are going to use them + if ( pos.piece_count(Us, QUEEN) + && pos.non_pawn_material(Us) >= QueenValueMidgame + RookValueMidgame) + { + ei.kingZone[Us] = (b | (Us == WHITE ? b >> 8 : b << 8)); + b &= ei.attackedBy[Us][PAWN]; + ei.kingAttackersCount[Us] = b ? count_1s(b) / 2 : 0; + ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0; + } else + ei.kingZone[Us] = ei.kingAttackersCount[Us] = 0; + } + + // evaluate_outposts() evaluates bishop and knight outposts squares template - void evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) { + Score evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) { const Color Them = (Us == WHITE ? BLACK : WHITE); + assert (Piece == BISHOP || Piece == KNIGHT); + // Initial bonus based on square - Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(Us, s)] - : KnightOutpostBonus[relative_square(Us, s)]); + Value bonus = OutpostBonus[Piece == BISHOP][relative_square(Us, s)]; // Increase bonus if supported by pawn, especially if the opponent has - // no minor piece which can exchange the outpost piece + // no minor piece which can exchange the outpost piece. if (bonus && bit_is_set(ei.attackedBy[Us][PAWN], s)) { if ( pos.pieces(KNIGHT, Them) == EmptyBoardBB @@ -502,23 +538,28 @@ namespace { else bonus += bonus / 2; } - ei.value += Sign[Us] * make_score(bonus, bonus); + return make_score(bonus, bonus); } // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given color - template - void evaluate_pieces(const Position& pos, EvalInfo& ei, Bitboard no_mob_area) { + template + Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard mobilityArea) { Bitboard b; Square s, ksq; int mob; File f; + Score bonus = SCORE_ZERO; + const BitCountType Full = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64 : CNT32; + const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; const Color Them = (Us == WHITE ? BLACK : WHITE); const Square* ptr = pos.piece_list_begin(Us, Piece); + ei.attackedBy[Us][Piece] = EmptyBoardBB; + while ((s = *ptr++) != SQ_NONE) { // Find attacked squares, including x-ray attacks for bishops and rooks @@ -541,41 +582,51 @@ namespace { ei.kingAttackersWeight[Us] += KingAttackWeights[Piece]; Bitboard bb = (b & ei.attackedBy[Them][KING]); if (bb) - ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15(bb); + ei.kingAdjacentZoneAttacksCount[Us] += count_1s(bb); } // Mobility - mob = (Piece != QUEEN ? count_1s_max_15(b & no_mob_area) - : count_1s(b & no_mob_area)); + mob = (Piece != QUEEN ? count_1s(b & mobilityArea) + : count_1s(b & mobilityArea)); - ei.mobility += Sign[Us] * MobilityBonus[Piece][mob]; + mobility += MobilityBonus[Piece][mob]; // 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 (bit_is_set(ei.attackedBy[Them][PAWN], s)) - ei.value -= Sign[Us] * ThreatedByPawnPenalty[Piece]; + bonus -= ThreatedByPawnPenalty[Piece]; // Bishop and knight outposts squares if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Us)) - evaluate_outposts(pos, ei, s); - - // Special patterns: trapped bishops on a7/h7/a2/h2 - // and trapped bishops on a1/h1/a8/h8 in Chess960. - if (Piece == BISHOP) - { - if (bit_is_set(MaskA7H7[Us], s)) - evaluate_trapped_bishop_a7h7(pos, s, Us, ei); - - if (Chess960 && bit_is_set(MaskA1H1[Us], s)) - evaluate_trapped_bishop_a1h1(pos, s, Us, ei); - } + bonus += evaluate_outposts(pos, ei, s); // Queen or rook on 7th rank if ( (Piece == ROOK || Piece == QUEEN) && relative_rank(Us, s) == RANK_7 && relative_rank(Us, pos.king_square(Them)) == RANK_8) { - ei.value += Sign[Us] * (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus); + bonus += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus); + } + + // Special extra evaluation for bishops + if (Piece == BISHOP && pos.is_chess960()) + { + // An important Chess960 pattern: A cornered bishop blocked by + // a friendly pawn diagonally in front of it is a very serious + // problem, especially when that pawn is also blocked. + if (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)) + { + Square d = pawn_push(Us) + (square_file(s) == FILE_A ? DELTA_E : DELTA_W); + if (pos.piece_on(s + d) == make_piece(Us, PAWN)) + { + if (!pos.square_is_empty(s + d + pawn_push(Us))) + bonus -= 2*TrappedBishopA1H1Penalty; + else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN)) + bonus -= TrappedBishopA1H1Penalty; + else + bonus -= TrappedBishopA1H1Penalty / 2; + } + } } // Special extra evaluation for rooks @@ -586,9 +637,9 @@ namespace { if (ei.pi->file_is_half_open(Us, f)) { if (ei.pi->file_is_half_open(Them, f)) - ei.value += Sign[Us] * RookOpenFileBonus; + bonus += RookOpenFileBonus; else - ei.value += Sign[Us] * RookHalfOpenFileBonus; + bonus += RookHalfOpenFileBonus; } // Penalize rooks which are trapped inside a king. Penalize more if @@ -604,8 +655,8 @@ namespace { { // 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.value -= Sign[Us] * make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 - : (TrappedRookPenalty - mob * 16), 0); + bonus -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 + : (TrappedRookPenalty - mob * 16), 0); } else if ( square_file(ksq) <= FILE_D && square_file(s) < square_file(ksq) @@ -613,11 +664,16 @@ namespace { { // 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.value -= Sign[Us] * make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 - : (TrappedRookPenalty - mob * 16), 0); + bonus -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 + : (TrappedRookPenalty - mob * 16), 0); } } } + + if (Trace) + TracedTerms[Us][Piece] = bonus; + + return bonus; } @@ -625,23 +681,23 @@ namespace { // and the type of attacked one. template - void evaluate_threats(const Position& pos, EvalInfo& ei) { + Score evaluate_threats(const Position& pos, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); Bitboard b; - Score bonus = make_score(0, 0); + Score bonus = SCORE_ZERO; // Enemy pieces not defended by a pawn and under our attack Bitboard weakEnemies = pos.pieces_of_color(Them) & ~ei.attackedBy[Them][PAWN] & ei.attackedBy[Us][0]; if (!weakEnemies) - return; + return SCORE_ZERO; - // Add bonus according to type of attacked enemy pieces and to the + // Add bonus according to type of attacked enemy piece and to the // type of attacking piece, from knights to queens. Kings are not - // considered because are already special handled in king evaluation. + // considered because are already handled in king evaluation. for (PieceType pt1 = KNIGHT; pt1 < KING; pt1++) { b = ei.attackedBy[Us][pt1] & weakEnemies; @@ -650,68 +706,62 @@ namespace { if (b & pos.pieces(pt2)) bonus += ThreatBonus[pt1][pt2]; } - ei.value += Sign[Us] * bonus; + return bonus; } // evaluate_pieces_of_color<>() assigns bonuses and penalties to all the // pieces of a given color. - template - void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei) { + template + Score evaluate_pieces_of_color(const Position& pos, EvalInfo& ei, Score& mobility) { const Color Them = (Us == WHITE ? BLACK : WHITE); + Score bonus = mobility = SCORE_ZERO; + // Do not include in mobility squares protected by enemy pawns or occupied by our pieces - const Bitboard no_mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us)); + const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us)); - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); + bonus += evaluate_pieces(pos, ei, mobility, mobilityArea); + bonus += evaluate_pieces(pos, ei, mobility, mobilityArea); + bonus += evaluate_pieces(pos, ei, mobility, mobilityArea); + bonus += evaluate_pieces(pos, ei, mobility, mobilityArea); // Sum up all attacked squares ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING]; + return bonus; } // evaluate_king<>() assigns bonuses and penalties to a king of a given color - template - void evaluate_king(const Position& pos, EvalInfo& ei) { + template + Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]) { + const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; const Color Them = (Us == WHITE ? BLACK : WHITE); Bitboard undefended, b, b1, b2, safe; - bool sente; - int attackUnits, shelter = 0; + int attackUnits; const Square ksq = pos.king_square(Us); // King shelter - if (relative_rank(Us, ksq) <= RANK_4) - { - shelter = ei.pi->get_king_shelter(pos, Us, ksq); - ei.value += Sign[Us] * make_score(shelter, 0); - } + Score bonus = ei.pi->king_shelter(pos, ksq); // King safety. This is quite complicated, and is almost certainly far // from optimally tuned. - if ( pos.piece_count(Them, QUEEN) >= 1 - && ei.kingAttackersCount[Them] >= 2 - && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame + if ( ei.kingAttackersCount[Them] >= 2 && ei.kingAdjacentZoneAttacksCount[Them]) { - // Is it the attackers turn to move? - sente = (Them == pos.side_to_move()); - // Find the attacked squares around the king which has no defenders // apart from the king itself - undefended = ei.attacked_by(Them) & ei.attacked_by(Us, KING); - undefended &= ~( 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)); + undefended = ei.attackedBy[Them][0] & ei.attackedBy[Us][KING]; + undefended &= ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] + | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK] + | ei.attackedBy[Us][QUEEN]); // Initialize the 'attackUnits' variable, which is used later on as an // index to the KingDangerTable[] array. The initial value is based on @@ -719,136 +769,154 @@ namespace { // attacked and undefended squares around our king, the square of the // king, and the quality of the pawn shelter. attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) - + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15(undefended)) + + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s(undefended)) + InitKingDanger[relative_square(Us, ksq)] - - shelter / 32; + - mg_value(ei.pi->king_shelter(pos, ksq)) / 32; // Analyse enemy's safe queen contact checks. First find undefended // squares around the king attacked by enemy queen... - b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them); + b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces_of_color(Them); if (b) { // ...then remove squares not supported by another enemy piece - b &= ( ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT) - | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK)); + b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); if (b) - attackUnits += QueenContactCheckBonus * count_1s_max_15(b) * (sente ? 2 : 1); + attackUnits += QueenContactCheckBonus + * count_1s(b) + * (Them == pos.side_to_move() ? 2 : 1); + } + + // Analyse enemy's safe rook contact checks. First find undefended + // squares around the king attacked by enemy rooks... + b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces_of_color(Them); + + // Consider only squares where the enemy rook gives check + b &= RookPseudoAttacks[ksq]; + + if (b) + { + // ...then remove squares not supported by another enemy piece + b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]); + if (b) + attackUnits += RookContactCheckBonus + * count_1s(b) + * (Them == pos.side_to_move() ? 2 : 1); } // Analyse enemy's safe distance checks for sliders and knights - safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us)); + safe = ~(pos.pieces_of_color(Them) | ei.attackedBy[Us][0]); b1 = pos.attacks_from(ksq) & safe; b2 = pos.attacks_from(ksq) & safe; // Enemy queen safe checks - b = (b1 | b2) & ei.attacked_by(Them, QUEEN); + b = (b1 | b2) & ei.attackedBy[Them][QUEEN]; if (b) - attackUnits += QueenCheckBonus * count_1s_max_15(b); + attackUnits += QueenCheckBonus * count_1s(b); // Enemy rooks safe checks - b = b1 & ei.attacked_by(Them, ROOK); + b = b1 & ei.attackedBy[Them][ROOK]; if (b) - attackUnits += RookCheckBonus * count_1s_max_15(b); + attackUnits += RookCheckBonus * count_1s(b); // Enemy bishops safe checks - b = b2 & ei.attacked_by(Them, BISHOP); + b = b2 & ei.attackedBy[Them][BISHOP]; if (b) - attackUnits += BishopCheckBonus * count_1s_max_15(b); + attackUnits += BishopCheckBonus * count_1s(b); // Enemy knights safe checks - b = pos.attacks_from(ksq) & ei.attacked_by(Them, KNIGHT) & safe; - if (b) - attackUnits += KnightCheckBonus * count_1s_max_15(b); - - // Analyse enemy's discovered checks (only for non-pawns right now, - // consider adding pawns later). - b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN); + b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe; if (b) - attackUnits += DiscoveredCheckBonus * count_1s_max_15(b) * (sente ? 2 : 1); + attackUnits += KnightCheckBonus * count_1s(b); // To index KingDangerTable[] attackUnits must be in [0, 99] range attackUnits = Min(99, Max(0, attackUnits)); // Finally, extract the king danger score from the KingDangerTable[] - // array and subtract the score from evaluation. Set also ei.kingDanger[] + // array and subtract the score from evaluation. Set also margins[] // value that will be used for pruning because this value can sometimes // be very big, and so capturing a single attacking piece can therefore // result in a score change far bigger than the value of the captured piece. - ei.value -= Sign[Us] * KingDangerTable[Us][attackUnits]; - ei.kingDanger[Us] = mg_value(KingDangerTable[Us][attackUnits]); + bonus -= KingDangerTable[Us][attackUnits]; + margins[Us] += mg_value(KingDangerTable[Us][attackUnits]); } + + if (Trace) + TracedTerms[Us][KING] = bonus; + + return bonus; } // evaluate_passed_pawns<>() evaluates the passed pawns of the given color template - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { + Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); + Score bonus = SCORE_ZERO; Bitboard squaresToQueen, defendedSquares, unsafeSquares, supportingPawns; - Bitboard b = ei.pi->passed_pawns() & pos.pieces_of_color(Us); + Bitboard b = ei.pi->passed_pawns(Us); - while (b) - { + if (!b) + return SCORE_ZERO; + + do { Square s = pop_1st_bit(&b); - assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN)); assert(pos.pawn_is_passed(Us, s)); int r = int(relative_rank(Us, s) - RANK_2); - int tr = Max(0, r * (r - 1)); + int rr = r * (r - 1); // Base bonus based on rank - Value mbonus = Value(20 * tr); - Value ebonus = Value(10 + r * r * 10); + Value mbonus = Value(20 * rr); + Value ebonus = Value(10 * (rr + r + 1)); - if (tr) + if (rr) { Square blockSq = s + pawn_push(Us); // Adjust bonus based on kings proximity - ebonus -= Value(square_distance(pos.king_square(Us), blockSq) * 3 * tr); - ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * 1 * tr); - ebonus += Value(square_distance(pos.king_square(Them), blockSq) * 6 * tr); + ebonus -= Value(square_distance(pos.king_square(Us), blockSq) * 3 * rr); + ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr); + ebonus += Value(square_distance(pos.king_square(Them), blockSq) * 6 * rr); // If the pawn is free to advance, increase bonus if (pos.square_is_empty(blockSq)) { squaresToQueen = squares_in_front_of(Us, s); - defendedSquares = squaresToQueen & ei.attacked_by(Us); - - // There are no enemy pawns in the pawn's path - assert(!(squaresToQueen & pos.pieces(PAWN, Them))); + defendedSquares = squaresToQueen & ei.attackedBy[Us][0]; // If there is an enemy rook or queen attacking the pawn from behind, // add all X-ray attacks by the rook or queen. Otherwise consider only // the squares in the pawn's path attacked or occupied by the enemy. - if ( (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them)) - && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from(s))) + if ( (squares_in_front_of(Them, s) & pos.pieces(ROOK, QUEEN, Them)) + && (squares_in_front_of(Them, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from(s))) unsafeSquares = squaresToQueen; else - unsafeSquares = squaresToQueen & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); + unsafeSquares = squaresToQueen & (ei.attackedBy[Them][0] | pos.pieces_of_color(Them)); // If there aren't enemy attacks or pieces along the path to queen give // huge bonus. Even bigger if we protect the pawn's path. if (!unsafeSquares) - ebonus += Value(tr * (squaresToQueen == defendedSquares ? 17 : 15)); + ebonus += Value(rr * (squaresToQueen == defendedSquares ? 17 : 15)); else // OK, there are enemy attacks or pieces (but not pawns). Are those // squares which are attacked by the enemy also attacked by us ? // If yes, big bonus (but smaller than when there are no enemy attacks), // if no, somewhat smaller bonus. - ebonus += Value(tr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8)); + ebonus += Value(rr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8)); // At last, add a small bonus when there are no *friendly* pieces // in the pawn's path. if (!(squaresToQueen & pos.pieces_of_color(Us))) - ebonus += Value(tr); + ebonus += Value(rr); } - } // tr != 0 + } // rr != 0 // Increase the bonus if the passed pawn is supported by a friendly pawn // on the same rank and a bit smaller if it's on the previous rank. @@ -866,169 +934,179 @@ namespace { // value if the other side has a rook or queen. if (square_file(s) == FILE_A || square_file(s) == FILE_H) { - if ( pos.non_pawn_material(Them) <= KnightValueMidgame - && pos.piece_count(Them, KNIGHT) <= 1) + if (pos.non_pawn_material(Them) <= KnightValueMidgame) ebonus += ebonus / 4; else if (pos.pieces(ROOK, QUEEN, Them)) ebonus -= ebonus / 4; } + bonus += make_score(mbonus, ebonus); - // Add the scores for this pawn to the middle game and endgame eval - ei.value += Sign[Us] * apply_weight(make_score(mbonus, ebonus), Weights[PassedPawns]); + } while (b); - } // while + // Add the scores to the middle game and endgame eval + return apply_weight(bonus, Weights[PassedPawns]); } - // evaluate_unstoppable_pawns() evaluates the unstoppable passed pawns for both sides + template + Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei) { - void evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei) { + const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; - int movesToGo[2] = {0, 0}; - Square pawnToGo[2] = {SQ_NONE, SQ_NONE}; + // Step 1. Hunt for unstoppable pawns. If we find at least one, record how many plies + // are required for promotion + int pliesToGo[2] = {256, 256}; for (Color c = WHITE; c <= BLACK; c++) { - // Skip evaluation if other side has non-pawn pieces + // Skip if other side has non-pawn pieces if (pos.non_pawn_material(opposite_color(c))) continue; - Bitboard b = ei.pi->passed_pawns() & pos.pieces_of_color(c); + Bitboard b = ei.pi->passed_pawns(c); while (b) { Square s = pop_1st_bit(&b); Square queeningSquare = relative_square(c, make_square(square_file(s), RANK_8)); - int d = square_distance(s, queeningSquare) - - square_distance(pos.king_square(opposite_color(c)), queeningSquare) - + int(c != pos.side_to_move()); - if (d < 0) - { - int mtg = RANK_8 - relative_rank(c, s); - int blockerCount = count_1s_max_15(squares_in_front_of(c, s) & pos.occupied_squares()); - mtg += blockerCount; - d += blockerCount; - if (d < 0 && (!movesToGo[c] || movesToGo[c] > mtg)) - { - movesToGo[c] = mtg; - pawnToGo[c] = s; - } - } + int mtg = RANK_8 - relative_rank(c, s) - int(relative_rank(c, s) == RANK_2); + int oppmtg = square_distance(pos.king_square(opposite_color(c)), queeningSquare) - int(c != pos.side_to_move()); + bool pathDefended = ((ei.attackedBy[c][0] & squares_in_front_of(c, s)) == squares_in_front_of(c, s)); + + if (mtg >= oppmtg && !pathDefended) + continue; + + int blockerCount = count_1s(squares_in_front_of(c, s) & pos.occupied_squares()); + mtg += blockerCount; + + if (mtg >= oppmtg && !pathDefended) + continue; + + int ptg = 2 * mtg - int(c == pos.side_to_move()); + + if (ptg < pliesToGo[c]) + pliesToGo[c] = ptg; } } - // Neither side has an unstoppable passed pawn? - if (!(movesToGo[WHITE] | movesToGo[BLACK])) - return; + // Step 2. If either side cannot promote at least three plies before the other side then + // situation becomes too complex and we give up. Otherwise we determine the possibly "winning side" + if (abs(pliesToGo[WHITE] - pliesToGo[BLACK]) < 3) + return make_score(0, 0); + + Color winnerSide = (pliesToGo[WHITE] < pliesToGo[BLACK] ? WHITE : BLACK); + Color loserSide = opposite_color(winnerSide); - // Does only one side have an unstoppable passed pawn? - if (!movesToGo[WHITE] || !movesToGo[BLACK]) + // Step 3. Can the losing side possibly create a new passed pawn and thus prevent the loss? + // We collect the potential candidates in potentialBB. + Bitboard pawnBB = pos.pieces(PAWN, loserSide); + Bitboard potentialBB = pawnBB; + const Bitboard passedBB = ei.pi->passed_pawns(loserSide); + + while(pawnBB) { - Color winnerSide = movesToGo[WHITE] ? WHITE : BLACK; - ei.value += make_score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * movesToGo[winnerSide]))); - } - else - { // Both sides have unstoppable pawns! Try to find out who queens - // first. We begin by transforming 'movesToGo' to the number of - // plies until the pawn queens for both sides. - movesToGo[WHITE] *= 2; - movesToGo[BLACK] *= 2; - movesToGo[pos.side_to_move()]--; - - Color winnerSide = movesToGo[WHITE] < movesToGo[BLACK] ? WHITE : BLACK; - Color loserSide = opposite_color(winnerSide); - - // If one side queens at least three plies before the other, that side wins - if (movesToGo[winnerSide] <= movesToGo[loserSide] - 3) - ei.value += Sign[winnerSide] * make_score(0, UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2))); - - // If one side queens one ply before the other and checks the king or attacks - // the undefended opponent's queening square, that side wins. To avoid cases - // where the opponent's king could move somewhere before first pawn queens we - // consider only free paths to queen for both pawns. - else if ( !(squares_in_front_of(WHITE, pawnToGo[WHITE]) & pos.occupied_squares()) - && !(squares_in_front_of(BLACK, pawnToGo[BLACK]) & pos.occupied_squares())) - { - assert(movesToGo[loserSide] - movesToGo[winnerSide] == 1); + Square psq = pop_1st_bit(&pawnBB); - Square winnerQSq = relative_square(winnerSide, make_square(square_file(pawnToGo[winnerSide]), RANK_8)); - Square loserQSq = relative_square(loserSide, make_square(square_file(pawnToGo[loserSide]), RANK_8)); + // Check direct advancement + int mtg = RANK_8 - relative_rank(loserSide, psq) - int(relative_rank(loserSide, psq) == RANK_2); + int ptg = 2 * mtg - int(loserSide == pos.side_to_move()); - Bitboard b = pos.occupied_squares(); - clear_bit(&b, pawnToGo[winnerSide]); - clear_bit(&b, pawnToGo[loserSide]); - b = queen_attacks_bb(winnerQSq, b); + // Check if (without even considering any obstacles) we're too far away + if (pliesToGo[winnerSide] + 3 <= ptg) + { + clear_bit(&potentialBB, psq); + continue; + } + + // If this is passed pawn, then it _may_ promote in time. We give up. + if (bit_is_set(passedBB, psq)) + return make_score(0, 0); - if ( (b & pos.pieces(KING, loserSide)) - ||(bit_is_set(b, loserQSq) && !bit_is_set(ei.attacked_by(loserSide), loserQSq))) - ei.value += Sign[winnerSide] * make_score(0, UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2))); + // Doubled pawn is worthless + if (squares_in_front_of(loserSide, psq) & (pos.pieces(PAWN, loserSide))) + { + clear_bit(&potentialBB, psq); + continue; } } - } + // Step 4. Check new passed pawn creation through king capturing and sacrifises + pawnBB = potentialBB; - // evaluate_trapped_bishop_a7h7() determines whether a bishop on a7/h7 - // (a2/h2 for black) is trapped by enemy pawns, and assigns a penalty - // if it is. + while(pawnBB) + { + Square psq = pop_1st_bit(&pawnBB); - void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, EvalInfo &ei) { + int mtg = RANK_8 - relative_rank(loserSide, psq) - int(relative_rank(loserSide, psq) == RANK_2); + int ptg = 2 * mtg - int(loserSide == pos.side_to_move()); - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + // Generate list of obstacles + Bitboard obsBB = passed_pawn_mask(loserSide, psq) & pos.pieces(PAWN, winnerSide); + const bool pawnIsOpposed = squares_in_front_of(loserSide, psq) & obsBB; + assert(obsBB); - Square b6 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B6 : SQ_G6); - Square b8 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B8 : SQ_G8); + // How many plies does it take to remove all the obstacles? + int sacptg = 0; + int realObsCount = 0; + int minKingDist = 256; - if ( pos.piece_on(b6) == piece_of_color_and_type(opposite_color(us), PAWN) - && pos.see(s, b6) < 0 - && pos.see(s, b8) < 0) - { - ei.value -= Sign[us] * TrappedBishopA7H7Penalty; - } - } + while(obsBB) + { + Square obSq = pop_1st_bit(&obsBB); + int minMoves = 256; + // Check pawns that can give support to overcome obstacle (Eg. wp: a4,b4 bp: b2. b4 is giving support) + if (!pawnIsOpposed && square_file(psq) != square_file(obSq)) + { + Bitboard supBB = in_front_bb(winnerSide, Square(obSq + (winnerSide == WHITE ? 8 : -8))) + & neighboring_files_bb(psq) & potentialBB; - // evaluate_trapped_bishop_a1h1() determines whether a bishop on a1/h1 - // (a8/h8 for black) is trapped by a friendly pawn on b2/g2 (b7/g7 for - // black), and assigns a penalty if it is. This pattern can obviously - // only occur in Chess960 games. + while(supBB) // This while-loop could be replaced with supSq = LSB/MSB(supBB) (depending on color) + { + Square supSq = pop_1st_bit(&supBB); + int dist = square_distance(obSq, supSq); + minMoves = Min(minMoves, dist - 2); + } - void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei) { + } - Piece pawn = piece_of_color_and_type(us, PAWN); - Square b2, b3, c3; + // Check pawns that can be sacrifised + Bitboard sacBB = passed_pawn_mask(winnerSide, obSq) & neighboring_files_bb(obSq) & potentialBB & ~(1ULL << psq); - assert(Chess960); - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + while(sacBB) // This while-loop could be replaced with sacSq = LSB/MSB(sacBB) (depending on color) + { + Square sacSq = pop_1st_bit(&sacBB); + int dist = square_distance(obSq, sacSq); + minMoves = Min(minMoves, dist - 2); + } - if (square_file(s) == FILE_A) - { - b2 = relative_square(us, SQ_B2); - b3 = relative_square(us, SQ_B3); - c3 = relative_square(us, SQ_C3); - } - else - { - b2 = relative_square(us, SQ_G2); - b3 = relative_square(us, SQ_G3); - c3 = relative_square(us, SQ_F3); - } + // If obstacle can be destroyed with immediate pawn sacrifise, it's not real obstacle + if (minMoves <= 0) + continue; - if (pos.piece_on(b2) == pawn) - { - Score penalty; + // Pawn sac calculations + sacptg += minMoves * 2; - if (!pos.square_is_empty(b3)) - penalty = 2 * TrappedBishopA1H1Penalty; - else if (pos.piece_on(c3) == pawn) - penalty = TrappedBishopA1H1Penalty; - else - penalty = TrappedBishopA1H1Penalty / 2; + // King capture calc + realObsCount++; + int kingDist = square_distance(pos.king_square(loserSide), obSq); + minKingDist = Min(minKingDist, kingDist); + } + + // Check if pawn sac plan _may_ save the day + if (pliesToGo[winnerSide] + 3 > ptg + sacptg) + return make_score(0, 0); - ei.value -= Sign[us] * penalty; + // Check if king capture plan _may_ save the day (contains some false positives) + int kingptg = (minKingDist + realObsCount) * 2; + if (pliesToGo[winnerSide] + 3 > ptg + kingptg) + return make_score(0, 0); } + + // Step 5. Assign bonus + const int Sign[2] = {1, -1}; + return Sign[winnerSide] * make_score(0, (Value) 0x500 - 0x20 * pliesToGo[winnerSide]); } @@ -1037,53 +1115,52 @@ namespace { // available for minor pieces on the central four files on ranks 2--4. Safe // squares one, two or three squares behind a friendly pawn are counted // twice. Finally, the space bonus is scaled by a weight taken from the - // material hash table. + // material hash table. The aim is to improve play on game opening. template - void evaluate_space(const Position& pos, EvalInfo& ei) { + int evaluate_space(const Position& pos, EvalInfo& ei) { + const BitCountType Max15 = HasPopCnt ? CNT_POPCNT : CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; const Color Them = (Us == WHITE ? BLACK : WHITE); // Find the safe squares for our pieces inside the area defined by - // SpaceMask[us]. A square is unsafe if it is attacked by an enemy + // SpaceMask[]. A square is unsafe if it is attacked by an enemy // pawn, or if it is undefended and attacked by an enemy piece. - Bitboard safeSquares = SpaceMask[Us] - & ~pos.pieces(PAWN, Us) - & ~ei.attacked_by(Them, PAWN) - & (ei.attacked_by(Us) | ~ei.attacked_by(Them)); + Bitboard safe = SpaceMask[Us] + & ~pos.pieces(PAWN, Us) + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][0] | ~ei.attackedBy[Them][0]); // Find all squares which are at most three squares behind some friendly pawn - Bitboard behindFriendlyPawns = pos.pieces(PAWN, Us); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 8 : behindFriendlyPawns << 8); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 16 : behindFriendlyPawns << 16); - - int space = count_1s_max_15(safeSquares) - + count_1s_max_15(behindFriendlyPawns & safeSquares); + Bitboard behind = pos.pieces(PAWN, Us); + behind |= (Us == WHITE ? behind >> 8 : behind << 8); + behind |= (Us == WHITE ? behind >> 16 : behind << 16); - ei.value += Sign[Us] * apply_weight(make_score(space * ei.mi->space_weight(), 0), Weights[Space]); + return count_1s(safe) + count_1s(behind & safe); } // apply_weight() applies an evaluation weight to a value trying to prevent overflow inline Score apply_weight(Score v, Score w) { - return make_score((int(mg_value(v)) * mg_value(w)) / 0x100, (int(eg_value(v)) * eg_value(w)) / 0x100); + return make_score((int(mg_value(v)) * mg_value(w)) / 0x100, + (int(eg_value(v)) * eg_value(w)) / 0x100); } - // 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. + // 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(const Score& v, Phase ph, const ScaleFactor sf[]) { + Value scale_by_game_phase(const Score& v, Phase ph, ScaleFactor sf) { assert(mg_value(v) > -VALUE_INFINITE && mg_value(v) < VALUE_INFINITE); assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE); assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); - Value ev = apply_scale_factor(eg_value(v), sf[(eg_value(v) > Value(0) ? WHITE : BLACK)]); + Value eg = eg_value(v); + Value ev = Value((eg * int(sf)) / SCALE_FACTOR_NORMAL); - int result = (mg_value(v) * ph + ev * (128 - ph)) / 128; - return Value(result & ~(GrainSize - 1)); + int result = (mg_value(v) * int(ph) + ev * int(128 - ph)) / 128; + return Value((result + GrainSize / 2) & ~(GrainSize - 1)); } @@ -1093,12 +1170,13 @@ namespace { Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { // Scale option value from 100 to 256 - int mg = get_option_value_int(mgOpt) * 256 / 100; - int eg = get_option_value_int(egOpt) * 256 / 100; + int mg = Options[mgOpt].value() * 256 / 100; + int eg = Options[egOpt].value() * 256 / 100; return apply_weight(make_score(mg, eg), internalWeight); } + // init_safety() initizes the king safety evaluation, based on UCI // parameters. It is called from read_weights(). @@ -1124,4 +1202,75 @@ namespace { for (int i = 0; i < 100; i++) KingDangerTable[c][i] = apply_weight(make_score(t[i], 0), Weights[KingDangerUs + c]); } + + + // trace_row() is an helper function used by tracing code to register the + // values of a single evaluation term. + + void trace_row(const char *name, int idx) { + + Score term_w = TracedTerms[WHITE][idx]; + Score term_b = TracedTerms[BLACK][idx]; + + switch (idx) { + case PST: case IMBALANCE: case PAWN: case UNSTOPPABLE: case TOTAL: + TraceStream << std::setw(20) << name << " | --- --- | --- --- | " + << std::setw(6) << to_cp(mg_value(term_w)) << " " + << std::setw(6) << to_cp(eg_value(term_w)) << " \n"; + break; + default: + TraceStream << std::setw(20) << name << " | " << std::noshowpos + << std::setw(5) << to_cp(mg_value(term_w)) << " " + << std::setw(5) << to_cp(eg_value(term_w)) << " | " + << std::setw(5) << to_cp(mg_value(term_b)) << " " + << std::setw(5) << to_cp(eg_value(term_b)) << " | " + << std::showpos + << std::setw(6) << to_cp(mg_value(term_w - term_b)) << " " + << std::setw(6) << to_cp(eg_value(term_w - term_b)) << " \n"; + } + } +} + + +/// trace_evaluate() is like evaluate() but instead of a value returns a string +/// suitable to be print on stdout with the detailed descriptions and values of +/// each evaluation term. Used mainly for debugging. + +std::string trace_evaluate(const Position& pos) { + + Value margin; + std::string totals; + + TraceStream.str(""); + TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2); + memset(TracedTerms, 0, 2 * 16 * sizeof(Score)); + + do_evaluate(pos, margin); + + totals = TraceStream.str(); + TraceStream.str(""); + + TraceStream << std::setw(21) << "Eval term " << "| White | Black | Total \n" + << " | MG EG | MG EG | MG EG \n" + << "---------------------+-------------+-------------+---------------\n"; + + trace_row("Material, PST, Tempo", PST); + trace_row("Material imbalance", IMBALANCE); + trace_row("Pawns", PAWN); + trace_row("Knights", KNIGHT); + trace_row("Bishops", BISHOP); + trace_row("Rooks", ROOK); + trace_row("Queens", QUEEN); + trace_row("Mobility", MOBILITY); + trace_row("King safety", KING); + trace_row("Threats", THREAT); + trace_row("Passed pawns", PASSED); + trace_row("Unstoppable pawns", UNSTOPPABLE); + trace_row("Space", SPACE); + + TraceStream << "---------------------+-------------+-------------+---------------\n"; + trace_row("Total", TOTAL); + TraceStream << totals; + + return TraceStream.str(); }