From e6b5d03cc4bdc95cc50537b5fb25ffa31787041b Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Sun, 25 Apr 2010 08:39:24 +0100 Subject: [PATCH] Small passed pawns evaluation cleanup Moved evaluation of unstoppable pawns out of evauation of passed pawns because event frequency is much lower. Added evaluate_unstoppable_pawns() that is called very seldom and contains all the unstoppable pawn logic. No functional change. Signed-off-by: Marco Costalba --- src/evaluate.cpp | 125 ++++++++++++++++++++++++----------------------- 1 file changed, 63 insertions(+), 62 deletions(-) diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 9bb6c1c0..36f88f44 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -280,7 +280,7 @@ namespace { template void evaluate_space(const Position& pos, EvalInfo& ei); - void evaluate_passed_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); @@ -308,6 +308,9 @@ namespace { template Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { + Bitboard b; + ScaleFactor factor[2]; + assert(pos.is_ok()); assert(threadID >= 0 && threadID < MAX_THREADS); assert(!pos.is_check()); @@ -328,7 +331,6 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { return ei.mi->evaluate(pos); // After get_material_info() call that modifies them - ScaleFactor factor[2]; factor[WHITE] = ei.mi->scale_factor(pos, WHITE); factor[BLACK] = ei.mi->scale_factor(pos, BLACK); @@ -344,14 +346,14 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // Initialize pawn attack bitboards for both sides ei.attackedBy[WHITE][PAWN] = ei.pi->pawn_attacks(WHITE); - ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK); - Bitboard b1 = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING]; - Bitboard b2 = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING]; - if (b1) - ei.kingAttackersCount[WHITE] = count_1s_max_15(b1)/2; + b = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING]; + if (b) + ei.kingAttackersCount[WHITE] = count_1s_max_15(b)/2; - if (b2) - ei.kingAttackersCount[BLACK] = count_1s_max_15(b2)/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); @@ -363,16 +365,17 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { evaluate_king(pos, ei); evaluate_king(pos, ei); - // Evaluate tactical threats, we need full attack info + // Evaluate tactical threats, we need full attack info including king evaluate_threats(pos, ei); evaluate_threats(pos, ei); - // Evaluate passed pawns. We evaluate passed pawns for both sides at once, - // because we need to know which side promotes first in positions where - // both sides have an unstoppable passed pawn. To be called after all attacks - // are computed, included king. - if (ei.pi->passed_pawns()) - evaluate_passed_pawns(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); Phase phase = ei.mi->game_phase(); @@ -870,17 +873,14 @@ namespace { } - // evaluate_passed_pawns_of_color() evaluates the passed pawns of the given color + // evaluate_passed_pawns<>() evaluates the passed pawns of the given color template - void evaluate_passed_pawns_of_color(const Position& pos, int movesToGo[], Square pawnToGo[], EvalInfo& ei) { + void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); - Bitboard b2, b3, b4; - Square ourKingSq = pos.king_square(Us); - Square theirKingSq = pos.king_square(Them); - Bitboard b = ei.pi->passed_pawns() & pos.pieces(PAWN, Us); + Bitboard b = ei.pi->passed_pawns() & pos.pieces_of_color(Us); while (b) { @@ -901,23 +901,23 @@ namespace { { Square blockSq = s + pawn_push(Us); - ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr); - ebonus -= Value(square_distance(ourKingSq, blockSq + pawn_push(Us)) * 1 * tr); - ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr); + 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); // If the pawn is free to advance, increase bonus if (pos.square_is_empty(blockSq)) { // There are no enemy pawns in the pawn's path - b2 = squares_in_front_of(Us, s); + Bitboard b2 = squares_in_front_of(Us, s); assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB); // Squares attacked by us - b4 = b2 & ei.attacked_by(Us); + Bitboard b4 = b2 & ei.attacked_by(Us); // Squares attacked or occupied by enemy pieces - b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); + Bitboard b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); // If there is an enemy rook or queen attacking the pawn from behind, // add all X-ray attacks by the rook or queen. @@ -945,38 +945,12 @@ namespace { } // tr != 0 // If the pawn is supported by a friendly pawn, increase bonus - b2 = pos.pieces(PAWN, Us) & neighboring_files_bb(s); - if (b2 & rank_bb(s)) + Bitboard b1 = pos.pieces(PAWN, Us) & neighboring_files_bb(s); + if (b1 & rank_bb(s)) ebonus += Value(r * 20); - else if (pos.attacks_from(s, Them) & b2) + else if (pos.attacks_from(s, Them) & b1) ebonus += Value(r * 12); - // If the other side has only a king, check whether the pawn is - // unstoppable - if (pos.non_pawn_material(Them) == Value(0)) - { - Square qsq; - int d; - - qsq = relative_square(Us, make_square(square_file(s), RANK_8)); - d = square_distance(s, qsq) - - square_distance(theirKingSq, qsq) - + int(Us != pos.side_to_move()); - - if (d < 0) - { - int mtg = RANK_8 - relative_rank(Us, s); - int blockerCount = count_1s_max_15(squares_in_front_of(Us,s) & pos.occupied_squares()); - mtg += blockerCount; - d += blockerCount; - if (d < 0 && (!movesToGo[Us] || movesToGo[Us] > mtg)) - { - movesToGo[Us] = mtg; - pawnToGo[Us] = s; - } - } - } - // Rook pawns are a special case: They are sometimes worse, and // sometimes better than other passed pawns. It is difficult to find // good rules for determining whether they are good or bad. For now, @@ -999,16 +973,43 @@ namespace { } - // evaluate_passed_pawns() evaluates the passed pawns for both sides + // evaluate_unstoppable_pawns() evaluates the unstoppable passed pawns for both sides - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { + void evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei) { int movesToGo[2] = {0, 0}; Square pawnToGo[2] = {SQ_NONE, SQ_NONE}; - // Evaluate pawns for each color - evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); - evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); + for (Color c = WHITE; c <= BLACK; c++) + { + // Skip evaluation 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); + + 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; + } + } + } + } // Neither side has an unstoppable passed pawn? if (!(movesToGo[WHITE] | movesToGo[BLACK])) -- 2.39.2