X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=754e40317b96b07b27281dd203e7e6303433d0d3;hp=24c8c5d41c344dd3cd501d6e955024eb7988ff17;hb=c1c09844525c764f869b29360519808aab5a7069;hpb=5ee7dfebf7a8c969e45cba632d21e2fd5727ba60 diff --git a/src/endgame.cpp b/src/endgame.cpp index 24c8c5d4..754e4031 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -17,21 +17,13 @@ along with this program. If not, see . */ - -//// -//// Includes -//// - #include -#include "bitbase.h" #include "bitcount.h" #include "endgame.h" +#include "pawns.h" - -//// -//// Local definitions -//// +extern int probe_kpk_bitbase(Square wksq, Square wpsq, Square bksq, Color stm); namespace { @@ -69,9 +61,6 @@ namespace { // and knight in KR vs KN endgames. const int KRKNKingKnightDistancePenalty[8] = { 0, 0, 4, 10, 20, 32, 48, 70 }; - // Bitbase for KP vs K - uint8_t KPKBitbase[24576]; - // Various inline functions for accessing the above arrays inline Value mate_table(Square s) { return Value(MateTable[s]); @@ -89,22 +78,6 @@ namespace { return Value(KRKNKingKnightDistancePenalty[d]); } - // Function for probing the KP vs K bitbase - int probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm); - -} - - -//// -//// Functions -//// - -/// init_bitbases() is called during program initialization, and simply loads -/// bitbases from disk into memory. At the moment, there is only the bitbase -/// for KP vs K, but we may decide to add other bitbases later. - -void init_bitbases() { - generate_kpk_bitbase(KPKBitbase); } @@ -115,8 +88,8 @@ void init_bitbases() { template<> Value EvaluationFunction::apply(const Position& pos) const { - assert(pos.non_pawn_material(weakerSide) == Value(0)); - assert(pos.piece_count(weakerSide, PAWN) == Value(0)); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); + assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO); Square winnerKSq = pos.king_square(strongerSide); Square loserKSq = pos.king_square(weakerSide); @@ -141,8 +114,8 @@ Value EvaluationFunction::apply(const Position& pos) const { template<> Value EvaluationFunction::apply(const Position& pos) const { - assert(pos.non_pawn_material(weakerSide) == Value(0)); - assert(pos.piece_count(weakerSide, PAWN) == Value(0)); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); + assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO); assert(pos.non_pawn_material(strongerSide) == KnightValueMidgame + BishopValueMidgame); assert(pos.piece_count(strongerSide, BISHOP) == 1); assert(pos.piece_count(strongerSide, KNIGHT) == 1); @@ -155,7 +128,7 @@ Value EvaluationFunction::apply(const Position& pos) const { // kbnk_mate_table() tries to drive toward corners A1 or H8, // if we have a bishop that cannot reach the above squares we // mirror the kings so to drive enemy toward corners A8 or H1. - if (!same_color_squares(bishopSquare, SQ_A1)) + if (opposite_color_squares(bishopSquare, SQ_A1)) { winnerKSq = flop_square(winnerKSq); loserKSq = flop_square(loserKSq); @@ -173,8 +146,8 @@ Value EvaluationFunction::apply(const Position& pos) const { template<> Value EvaluationFunction::apply(const Position& pos) const { - assert(pos.non_pawn_material(strongerSide) == Value(0)); - assert(pos.non_pawn_material(weakerSide) == Value(0)); + assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); assert(pos.piece_count(strongerSide, PAWN) == 1); assert(pos.piece_count(weakerSide, PAWN) == 0); @@ -203,7 +176,7 @@ Value EvaluationFunction::apply(const Position& pos) const { wpsq = flop_square(wpsq); } - if (!probe_kpk(wksq, wpsq, bksq, stm)) + if (!probe_kpk_bitbase(wksq, wpsq, bksq, stm)) return VALUE_DRAW; Value result = VALUE_KNOWN_WIN @@ -357,7 +330,7 @@ Value EvaluationFunction::apply(const Position& pos) const { result += Value(square_distance(bksq, nsq) * 32); // Bonus for restricting the knight's mobility - result += Value((8 - count_1s_max_15(pos.attacks_from(nsq))) * 8); + result += Value((8 - count_1s(pos.attacks_from(nsq))) * 8); return strongerSide == pos.side_to_move() ? result : -result; } @@ -367,12 +340,12 @@ Value EvaluationFunction::apply(const Position& pos) const { /// king alone are always draw. template<> Value EvaluationFunction::apply(const Position&) const { - return Value(0); + return VALUE_DRAW; } template<> Value EvaluationFunction::apply(const Position&) const { - return Value(0); + return VALUE_DRAW; } /// KBPKScalingFunction scales endgames where the stronger side has king, @@ -401,8 +374,8 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square queeningSq = relative_square(strongerSide, make_square(pawnFile, RANK_8)); Square kingSq = pos.king_square(weakerSide); - if ( !same_color_squares(queeningSq, bishopSq) - && file_distance(square_file(kingSq), pawnFile) <= 1) + if ( opposite_color_squares(queeningSq, bishopSq) + && abs(square_file(kingSq) - pawnFile) <= 1) { // The bishop has the wrong color, and the defending king is on the // file of the pawn(s) or the neighboring file. Find the rank of the @@ -446,8 +419,8 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square kingSq = pos.king_square(weakerSide); if ( relative_rank(weakerSide, kingSq) <= RANK_2 && relative_rank(weakerSide, pos.king_square(strongerSide)) >= RANK_4 - && (pos.pieces(ROOK, weakerSide) & relative_rank_bb(weakerSide, RANK_3)) - && (pos.pieces(PAWN, weakerSide) & relative_rank_bb(weakerSide, RANK_2)) + && (pos.pieces(ROOK, weakerSide) & rank_bb(relative_rank(weakerSide, RANK_3))) + && (pos.pieces(PAWN, weakerSide) & rank_bb(relative_rank(weakerSide, RANK_2))) && (pos.attacks_from(kingSq) & pos.pieces(PAWN, weakerSide))) { Square rsq = pos.piece_list(weakerSide, ROOK, 0); @@ -625,9 +598,9 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { template<> ScaleFactor ScalingFunction::apply(const Position& pos) const { - assert(pos.non_pawn_material(strongerSide) == Value(0)); + assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO); assert(pos.piece_count(strongerSide, PAWN) >= 2); - assert(pos.non_pawn_material(weakerSide) == Value(0)); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); assert(pos.piece_count(weakerSide, PAWN) == 0); Square ksq = pos.king_square(weakerSide); @@ -678,12 +651,12 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // Case 1: Defending king blocks the pawn, and cannot be driven away if ( square_file(weakerKingSq) == square_file(pawnSq) && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq) - && ( !same_color_squares(weakerKingSq, strongerBishopSq) + && ( opposite_color_squares(weakerKingSq, strongerBishopSq) || relative_rank(strongerSide, weakerKingSq) <= RANK_6)) return SCALE_FACTOR_ZERO; // Case 2: Opposite colored bishops - if (!same_color_squares(strongerBishopSq, weakerBishopSq)) + if (opposite_color_squares(strongerBishopSq, weakerBishopSq)) { // We assume that the position is drawn in the following three situations: // @@ -699,11 +672,12 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { return SCALE_FACTOR_ZERO; else { - Bitboard ray = ray_bb(pawnSq, (strongerSide == WHITE)? SIGNED_DIR_N : SIGNED_DIR_S); - if (ray & pos.pieces(KING, weakerSide)) + Bitboard path = squares_in_front_of(strongerSide, pawnSq); + + if (path & pos.pieces(KING, weakerSide)) return SCALE_FACTOR_ZERO; - if ( (pos.attacks_from(weakerBishopSq) & ray) + if ( (pos.attacks_from(weakerBishopSq) & path) && square_distance(weakerBishopSq, pawnSq) >= 3) return SCALE_FACTOR_ZERO; } @@ -727,8 +701,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square wbsq = pos.piece_list(strongerSide, BISHOP, 0); Square bbsq = pos.piece_list(weakerSide, BISHOP, 0); - if (same_color_squares(wbsq, bbsq)) - // Not opposite-colored bishops, no scaling + if (!opposite_color_squares(wbsq, bbsq)) return SCALE_FACTOR_NONE; Square ksq = pos.king_square(weakerSide); @@ -756,7 +729,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // some square in the frontmost pawn's path. if ( square_file(ksq) == square_file(blockSq1) && relative_rank(strongerSide, ksq) >= relative_rank(strongerSide, blockSq1) - && !same_color_squares(ksq, wbsq)) + && opposite_color_squares(ksq, wbsq)) return SCALE_FACTOR_ZERO; else return SCALE_FACTOR_NONE; @@ -766,14 +739,14 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // in front of the frontmost pawn's path, and the square diagonally behind // this square on the file of the other pawn. if ( ksq == blockSq1 - && !same_color_squares(ksq, wbsq) + && opposite_color_squares(ksq, wbsq) && ( bbsq == blockSq2 || (pos.attacks_from(blockSq2) & pos.pieces(BISHOP, weakerSide)) - || rank_distance(r1, r2) >= 2)) + || abs(r1 - r2) >= 2)) return SCALE_FACTOR_ZERO; else if ( ksq == blockSq2 - && !same_color_squares(ksq, wbsq) + && opposite_color_squares(ksq, wbsq) && ( bbsq == blockSq1 || (pos.attacks_from(blockSq1) & pos.pieces(BISHOP, weakerSide)))) return SCALE_FACTOR_ZERO; @@ -807,7 +780,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { if ( square_file(weakerKingSq) == square_file(pawnSq) && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq) - && ( !same_color_squares(weakerKingSq, strongerBishopSq) + && ( opposite_color_squares(weakerKingSq, strongerBishopSq) || relative_rank(strongerSide, weakerKingSq) <= RANK_6)) return SCALE_FACTOR_ZERO; @@ -824,7 +797,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { assert(pos.non_pawn_material(strongerSide) == KnightValueMidgame); assert(pos.piece_count(strongerSide, KNIGHT) == 1); assert(pos.piece_count(strongerSide, PAWN) == 1); - assert(pos.non_pawn_material(weakerSide) == Value(0)); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); assert(pos.piece_count(weakerSide, PAWN) == 0); Square pawnSq = pos.piece_list(strongerSide, PAWN, 0); @@ -851,8 +824,8 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { template<> ScaleFactor ScalingFunction::apply(const Position& pos) const { - assert(pos.non_pawn_material(strongerSide) == Value(0)); - assert(pos.non_pawn_material(weakerSide) == Value(0)); + assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO); + assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); assert(pos.piece_count(WHITE, PAWN) == 1); assert(pos.piece_count(BLACK, PAWN) == 1); @@ -889,21 +862,5 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // Probe the KPK bitbase with the weakest side's pawn removed. If it's a // draw, it's probably at least a draw even with the pawn. - return probe_kpk(wksq, wpsq, bksq, stm) ? SCALE_FACTOR_NONE : SCALE_FACTOR_ZERO; -} - - -namespace { - - // Probe the KP vs K bitbase - - int probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm) { - - int wp = square_file(wpsq) + 4 * (square_rank(wpsq) - 1); - int index = int(stm) + 2 * bksq + 128 * wksq + 8192 * wp; - - assert(index >= 0 && index < 24576 * 8); - - return KPKBitbase[index / 8] & (1 << (index & 7)); - } + return probe_kpk_bitbase(wksq, wpsq, bksq, stm) ? SCALE_FACTOR_NONE : SCALE_FACTOR_ZERO; }