X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=0846344223137f93a2372c737b6a553609e8c5a4;hp=07decab1fd4c52e9c490f5468c5f4c94d9d73b31;hb=0ddf84870ad9f7fb4309e992e1e5eae968577958;hpb=d4876dc96395f5592bfbc25b2eca2360db0655e6 diff --git a/src/pawns.cpp b/src/pawns.cpp index 07decab1..08463442 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] = { @@ -78,26 +81,6 @@ namespace { //// Functions //// -/// PawnInfoTable c'tor and d'tor instantiated one each thread - -PawnInfoTable::PawnInfoTable() { - - entries = new PawnInfo[PawnTableSize]; - - if (!entries) - { - std::cerr << "Failed to allocate " << (PawnTableSize * sizeof(PawnInfo)) - << " bytes for pawn hash table." << std::endl; - Application::exit_with_failure(); - } -} - - -PawnInfoTable::~PawnInfoTable() { - - delete [] entries; -} - /// 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 @@ -109,8 +92,7 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const { assert(pos.is_ok()); Key key = pos.get_pawn_key(); - unsigned index = unsigned(key & (PawnTableSize - 1)); - PawnInfo* pi = entries + index; + PawnInfo* pi = find(key); // If pi->key matches the position's pawn hash key, it means that we // have analysed this pawn structure before, and we can simply return @@ -120,18 +102,19 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const { // Clear the PawnInfo object, and set the key 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; } @@ -150,11 +133,6 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns, const BitCountType Max15 = CpuIs64Bit ? CNT64_MAX15 : CNT32_MAX15; const Square* ptr = pos.piece_list_begin(Us, PAWN); - // Initialize halfOpenFiles[] - for (f = FILE_A; f <= FILE_H; f++) - if (!(ourPawns & file_bb(f))) - pi->halfOpenFiles[Us] |= (1 << f); - // Loop through all pawns of the current color and score each pawn while ((s = *ptr++) != SQ_NONE) { @@ -163,13 +141,16 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns, f = square_file(s); r = square_rank(s); + // 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(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; @@ -209,40 +190,27 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns, && (b = attack_span_mask(opposite_color(Us), s + pawn_push(Us)) & ourPawns) != EmptyBoardBB && count_1s(b) >= count_1s(attack_span_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; - // Mark the pawn as passed. Pawn will be properly scored in evaluation - // because we need full attack info to evaluate passed pawns. - if (passed) + // 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 (!opposed) - value -= IsolatedPawnPenalty[f] / 2; - } + value -= IsolatedPawnPenalty[opposed][f]; + if (doubled) - value -= DoubledPawnPenalty[f]; + value -= DoubledPawnPenalty[opposed][f]; if (backward) - { - value -= BackwardPawnPenalty[f]; - if (!opposed) - value -= BackwardPawnPenalty[f] / 2; - } + value -= BackwardPawnPenalty[opposed][f]; + if (chain) value += ChainBonus[f]; if (candidate) value += CandidateBonus[relative_rank(Us, s)]; } - return value; } -