From: Marco Costalba Date: Wed, 7 Jan 2009 13:17:50 +0000 (+0100) Subject: Another micro-optmization in valuate_passed_pawns() X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=5cacefe7c67b34dafe494e5155bce717289eeaf1;ds=sidebyside Another micro-optmization in valuate_passed_pawns() very small gain, but still a gain at the cost of an extra indentation level. Signed-off-by: Marco Costalba --- diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 4b98a13c..23597231 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -483,7 +483,7 @@ Value quick_evaluate(const Position &pos) { assert(pos.is_ok()); static const - ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; + ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; Value mgv = pos.mg_value(); Value egv = pos.eg_value(); @@ -814,7 +814,7 @@ namespace { && !bit_is_set(p.pinned_pieces(them), from) && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us)) && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))) - + ei.mateThreat[them] = make_move(from, to); } } @@ -932,50 +932,53 @@ namespace { Value ebonus = Value(10 + r * r * 10); // Adjust bonus based on king proximity - 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); - - // If the pawn is free to advance, increase bonus - if (tr != 0 && pos.square_is_empty(blockSq)) + if (tr != 0) { - b2 = squares_in_front_of(us, s); - b3 = b2 & ei.attacked_by(them); - b4 = b2 & ei.attacked_by(us); - - // If there is an enemy rook or queen attacking the pawn from behind, - // add all X-ray attacks by the rook or queen. - if ( bit_is_set(ei.attacked_by(them,ROOK) | ei.attacked_by(them,QUEEN),s) - && (squares_behind(us, s) & pos.rooks_and_queens(them))) - b3 = b2; + 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); - if ((b2 & pos.pieces_of_color(them)) == EmptyBoardBB) + // If the pawn is free to advance, increase bonus + if (pos.square_is_empty(blockSq)) { - // There are no enemy pieces in the pawn's path! Are any of the - // squares in the pawn's path attacked by the enemy? - if (b3 == EmptyBoardBB) - // No enemy attacks, huge bonus! - ebonus += Value(tr * (b2 == b4 ? 17 : 15)); + b2 = squares_in_front_of(us, s); + b3 = b2 & ei.attacked_by(them); + b4 = b2 & ei.attacked_by(us); + + // If there is an enemy rook or queen attacking the pawn from behind, + // add all X-ray attacks by the rook or queen. + if ( bit_is_set(ei.attacked_by(them,ROOK) | ei.attacked_by(them,QUEEN),s) + && (squares_behind(us, s) & pos.rooks_and_queens(them))) + b3 = b2; + + if ((b2 & pos.pieces_of_color(them)) == EmptyBoardBB) + { + // There are no enemy pieces in the pawn's path! Are any of the + // squares in the pawn's path attacked by the enemy? + if (b3 == EmptyBoardBB) + // No enemy attacks, huge bonus! + ebonus += Value(tr * (b2 == b4 ? 17 : 15)); + else + // OK, there are enemy attacks. 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 * ((b3 & b4) == b3 ? 13 : 8)); + } else - // OK, there are enemy attacks. 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 * ((b3 & b4) == b3 ? 13 : 8)); - } - else - { - // There are some enemy pieces in the pawn's path. While this is - // sad, we still assign a moderate bonus if all squares in the path - // which are either occupied by or attacked by enemy pieces are - // also attacked by us. - if (((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB) - ebonus += Value(tr * 6); + { + // There are some enemy pieces in the pawn's path. While this is + // sad, we still assign a moderate bonus if all squares in the path + // which are either occupied by or attacked by enemy pieces are + // also attacked by us. + if (((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB) + ebonus += Value(tr * 6); + } + // At last, add a small bonus when there are no *friendly* pieces + // in the pawn's path. + if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB) + ebonus += Value(tr); } - // At last, add a small bonus when there are no *friendly* pieces - // in the pawn's path. - if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB) - ebonus += Value(tr); } // If the pawn is supported by a friendly pawn, increase bonus