X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=e3201081635be80e9aaa5a3520b13ff90cf3d21e;hp=c2d60e4b4b3b30b65b29f79d4c02e5711642b4db;hb=efeb37c33f15a903dbe5706529a7a26511e9ca58;hpb=9079bab84cab03c20f2c2d889d8b419f1d696a09 diff --git a/src/pawns.cpp b/src/pawns.cpp index c2d60e4b..e3201081 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -40,23 +40,26 @@ namespace { #define S(mg, eg) make_score(mg, eg) - // Doubled pawn penalty by file - const Score DoubledPawnPenalty[8] = { - S(13, 43), S(20, 48), S(23, 48), S(23, 48), - S(23, 48), S(23, 48), S(20, 48), S(13, 43) - }; - - // Isolated pawn penalty by file - const Score IsolatedPawnPenalty[8] = { - S(25, 30), S(36, 35), S(40, 35), S(40, 35), - S(40, 35), S(40, 35), S(36, 35), S(25, 30) - }; - - // Backward pawn penalty by file - const Score BackwardPawnPenalty[8] = { - S(20, 28), S(29, 31), S(33, 31), S(33, 31), - S(33, 31), S(33, 31), S(29, 31), S(20, 28) - }; + // Doubled pawn penalty by opposed flag and file + const Score DoubledPawnPenalty[2][8] = { + { S(13, 43), S(20, 48), S(23, 48), S(23, 48), + S(23, 48), S(23, 48), S(20, 48), S(13, 43) }, + { S(13, 43), S(20, 48), S(23, 48), S(23, 48), + S(23, 48), S(23, 48), S(20, 48), S(13, 43) }}; + + // Isolated pawn penalty by opposed flag and file + const Score IsolatedPawnPenalty[2][8] = { + { S(37, 45), S(54, 52), S(60, 52), S(60, 52), + S(60, 52), S(60, 52), S(54, 52), S(37, 45) }, + { S(25, 30), S(36, 35), S(40, 35), S(40, 35), + S(40, 35), S(40, 35), S(36, 35), S(25, 30) }}; + + // Backward pawn penalty by opposed flag and file + const Score BackwardPawnPenalty[2][8] = { + { S(30, 42), S(43, 46), S(49, 46), S(49, 46), + S(49, 46), S(49, 46), S(43, 46), S(30, 42) }, + { S(20, 28), S(29, 31), S(33, 31), S(33, 31), + S(33, 31), S(33, 31), S(29, 31), S(20, 28) }}; // Pawn chain membership bonus by file const Score ChainBonus[8] = { @@ -70,36 +73,6 @@ namespace { S(34,68), S(83,166), S(0, 0), S( 0, 0) }; - // Pawn storm tables for positions with opposite castling - const int QStormTable[64] = { - 0, 0, 0, 0, 0, 0, 0, 0, - -22,-22,-22,-14,-6, 0, 0, 0, - -6,-10,-10,-10,-6, 0, 0, 0, - 4, 12, 16, 12, 4, 0, 0, 0, - 16, 23, 23, 16, 0, 0, 0, 0, - 23, 31, 31, 23, 0, 0, 0, 0, - 23, 31, 31, 23, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0 - }; - - const int KStormTable[64] = { - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0,-10,-19,-28,-33,-33, - 0, 0, 0,-10,-15,-19,-24,-24, - 0, 0, 0, 0, 1, 1, 1, 1, - 0, 0, 0, 0, 1, 10, 19, 19, - 0, 0, 0, 0, 1, 19, 31, 27, - 0, 0, 0, 0, 0, 22, 31, 22, - 0, 0, 0, 0, 0, 0, 0, 0 - }; - - // Pawn storm open file bonuses by file - const int16_t KStormOpenFileBonus[8] = { 31, 31, 18, 0, 0, 0, 0, 0 }; - const int16_t QStormOpenFileBonus[8] = { 0, 0, 0, 0, 0, 26, 42, 26 }; - - // Pawn storm lever bonuses by file - const int StormLeverBonus[8] = { -8, -8, -13, 0, 0, -13, -8, -8 }; - #undef S } @@ -110,15 +83,17 @@ namespace { /// PawnInfoTable c'tor and d'tor instantiated one each thread -PawnInfoTable::PawnInfoTable(unsigned numOfEntries) : size(numOfEntries) { +PawnInfoTable::PawnInfoTable() { + + entries = new PawnInfo[PawnTableSize]; - entries = new PawnInfo[size]; if (!entries) { - std::cerr << "Failed to allocate " << (numOfEntries * sizeof(PawnInfo)) + std::cerr << "Failed to allocate " << (PawnTableSize * sizeof(PawnInfo)) << " bytes for pawn hash table." << std::endl; - Application::exit_with_failure(); + exit(EXIT_FAILURE); } + memset(entries, 0, PawnTableSize * sizeof(PawnInfo)); } @@ -128,16 +103,6 @@ PawnInfoTable::~PawnInfoTable() { } -/// PawnInfo::clear() resets to zero the PawnInfo entry. Note that -/// kingSquares[] is initialized to SQ_NONE instead. - -void PawnInfo::clear() { - - memset(this, 0, sizeof(PawnInfo)); - kingSquares[WHITE] = kingSquares[BLACK] = SQ_NONE; -} - - /// PawnInfoTable::get_pawn_info() takes a position object as input, computes /// a PawnInfo object, and returns a pointer to it. The result is also stored /// in a hash table, so we don't have to recompute everything when the same @@ -148,7 +113,7 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const { assert(pos.is_ok()); Key key = pos.get_pawn_key(); - int index = int(key & (size - 1)); + unsigned index = unsigned(key & (PawnTableSize - 1)); PawnInfo* pi = entries + index; // If pi->key matches the position's pawn hash key, it means that we @@ -158,18 +123,20 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const { return pi; // Clear the PawnInfo object, and set the key - pi->clear(); + memset(pi, 0, sizeof(PawnInfo)); + pi->halfOpenFiles[WHITE] = pi->halfOpenFiles[BLACK] = 0xFF; + pi->kingSquares[WHITE] = pi->kingSquares[BLACK] = SQ_NONE; pi->key = key; // Calculate pawn attacks - Bitboard whitePawns = pos.pieces(PAWN, WHITE); - Bitboard blackPawns = pos.pieces(PAWN, BLACK); - pi->pawnAttacks[WHITE] = ((whitePawns << 9) & ~FileABB) | ((whitePawns << 7) & ~FileHBB); - pi->pawnAttacks[BLACK] = ((blackPawns >> 7) & ~FileABB) | ((blackPawns >> 9) & ~FileHBB); + Bitboard wPawns = pos.pieces(PAWN, WHITE); + Bitboard bPawns = pos.pieces(PAWN, BLACK); + pi->pawnAttacks[WHITE] = ((wPawns << 9) & ~FileABB) | ((wPawns << 7) & ~FileHBB); + pi->pawnAttacks[BLACK] = ((bPawns >> 7) & ~FileABB) | ((bPawns >> 9) & ~FileHBB); // Evaluate pawns for both colors - pi->value = evaluate_pawns(pos, whitePawns, blackPawns, pi) - - evaluate_pawns(pos, blackPawns, whitePawns, pi); + pi->value = evaluate_pawns(pos, wPawns, bPawns, pi) + - evaluate_pawns(pos, bPawns, wPawns, pi); return pi; } @@ -183,58 +150,44 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns, Square s; File f; Rank r; - int bonus; bool passed, isolated, doubled, opposed, chain, backward, candidate; - Score value = make_score(0, 0); + Score value = SCORE_ZERO; + const BitCountType Max15 = CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; const Square* ptr = pos.piece_list_begin(Us, PAWN); - // Initialize pawn storm scores by giving bonuses for open files - for (f = FILE_A; f <= FILE_H; f++) - if (!(ourPawns & file_bb(f))) - { - pi->ksStormValue[Us] += KStormOpenFileBonus[f]; - pi->qsStormValue[Us] += QStormOpenFileBonus[f]; - pi->halfOpenFiles[Us] |= (1 << f); - } - // Loop through all pawns of the current color and score each pawn while ((s = *ptr++) != SQ_NONE) { - f = square_file(s); - r = square_rank(s); - assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN)); - // Calculate kingside and queenside pawn storm scores for both colors to be - // used when evaluating middle game positions with opposite side castling. - bonus = (f >= FILE_F ? evaluate_pawn_storm(s, r, f, theirPawns) : 0); - pi->ksStormValue[Us] += KStormTable[relative_square(Us, s)] + bonus; + f = square_file(s); + r = square_rank(s); - bonus = (f <= FILE_C ? evaluate_pawn_storm(s, r, f, theirPawns) : 0); - pi->qsStormValue[Us] += QStormTable[relative_square(Us, s)] + bonus; + // This file cannot be half open + pi->halfOpenFiles[Us] &= ~(1 << f); // Our rank plus previous one. Used for chain detection. - b = rank_bb(r) | rank_bb(r + (Us == WHITE ? -1 : 1)); + b = rank_bb(r) | rank_bb(Us == WHITE ? r - Rank(1) : r + Rank(1)); // Passed, isolated, doubled or member of a pawn // chain (but not the backward one) ? passed = !(theirPawns & passed_pawn_mask(Us, s)); - doubled = ourPawns & squares_behind(Us, s); + doubled = ourPawns & squares_in_front_of(Us, s); opposed = theirPawns & squares_in_front_of(Us, s); isolated = !(ourPawns & neighboring_files_bb(f)); chain = ourPawns & neighboring_files_bb(f) & b; // Test for backward pawn // + backward = false; + // If the pawn is passed, isolated, or member of a pawn chain // it cannot be backward. If can capture an enemy pawn or if // there are friendly pawns behind on neighboring files it cannot // be backward either. - if ( (passed | isolated | chain) - || (ourPawns & outpost_mask(opposite_color(Us), s)) - || (pos.attacks_from(s, Us) & theirPawns)) - backward = false; - else + if ( !(passed | isolated | chain) + && !(ourPawns & attack_span_mask(opposite_color(Us), s)) + && !(pos.attacks_from(s, Us) & theirPawns)) { // We now know that there are no friendly pawns beside or behind this // pawn on neighboring files. We now check whether the pawn is @@ -252,98 +205,34 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns, backward = (b | (Us == WHITE ? b << 8 : b >> 8)) & theirPawns; } - assert(passed | opposed | (outpost_mask(Us, s) & theirPawns)); + assert(passed | opposed | (attack_span_mask(Us, s) & theirPawns)); // Test for candidate passed pawn candidate = !(opposed | passed) - && (b = outpost_mask(opposite_color(Us), s + pawn_push(Us)) & ourPawns) != EmptyBoardBB - && count_1s_max_15(b) >= count_1s_max_15(outpost_mask(Us, s) & theirPawns); - - // In order to prevent doubled passed pawns from receiving a too big - // bonus, only the frontmost passed pawn on each file is considered as - // a true passed pawn. - if (passed && (ourPawns & squares_in_front_of(Us, s))) - passed = false; + && (b = attack_span_mask(opposite_color(Us), s + pawn_push(Us)) & ourPawns) != EmptyBoardBB + && count_1s(b) >= count_1s(attack_span_mask(Us, s) & theirPawns); // Mark the pawn as passed. Pawn will be properly scored in evaluation - // because we need full attack info to evaluate passed pawns. - if (passed) - set_bit(&(pi->passedPawns), s); + // because we need full attack info to evaluate passed pawns. Only the + // frontmost passed pawn on each file is considered a true passed pawn. + if (passed && !doubled) + set_bit(&(pi->passedPawns[Us]), s); // Score this pawn if (isolated) - { - value -= IsolatedPawnPenalty[f]; - if (!(theirPawns & file_bb(f))) - value -= IsolatedPawnPenalty[f] / 2; - } + value -= IsolatedPawnPenalty[opposed][f]; + if (doubled) - value -= DoubledPawnPenalty[f]; + value -= DoubledPawnPenalty[opposed][f]; if (backward) - { - value -= BackwardPawnPenalty[f]; - if (!(theirPawns & file_bb(f))) - value -= BackwardPawnPenalty[f] / 2; - } + value -= BackwardPawnPenalty[opposed][f]; + if (chain) value += ChainBonus[f]; if (candidate) value += CandidateBonus[relative_rank(Us, s)]; } - return value; } - - -/// PawnInfoTable::evaluate_pawn_storm() evaluates each pawn which seems -/// to have good chances of creating an open file by exchanging itself -/// against an enemy pawn on an adjacent file. - -template -int PawnInfoTable::evaluate_pawn_storm(Square s, Rank r, File f, Bitboard theirPawns) const { - - const Bitboard StormFilesBB = (Side == KingSide ? FileFBB | FileGBB | FileHBB - : FileABB | FileBBB | FileCBB); - const int K = (Side == KingSide ? 2 : 4); - const File RookFile = (Side == KingSide ? FILE_H : FILE_A); - - Bitboard b = outpost_mask(Us, s) & theirPawns & StormFilesBB; - int bonus = 0; - - while (b) - { - // Give a bonus according to the distance of the nearest enemy pawn - Square s2 = pop_1st_bit(&b); - Rank r2 = square_rank(s2); - int v = StormLeverBonus[f] - K * rank_distance(r, r2); - - // If enemy pawn has no pawn beside itself is particularly vulnerable. - // Big bonus, especially against a weakness on the rook file - if (!(theirPawns & neighboring_files_bb(s2) & rank_bb(s2))) - v *= (square_file(s2) == RookFile ? 4 : 2); - - bonus += v; - } - return bonus; -} - - -/// PawnInfo::updateShelter calculates and caches king shelter. It is called -/// only when king square changes, about 20% of total get_king_shelter() calls. -int PawnInfo::updateShelter(const Position& pos, Color c, Square ksq) { - - Bitboard pawns = pos.pieces(PAWN, c) & this_and_neighboring_files_bb(ksq); - unsigned shelter = 0; - unsigned r = ksq & (7 << 3); - - for (int i = 1, k = (c ? -8 : 8); i < 4; i++) - { - r += k; - shelter += BitCount8Bit[(pawns >> r) & 0xFF] * (128 >> i); - } - kingSquares[c] = ksq; - kingShelters[c] = shelter; - return shelter; -}