From: Marco Costalba Date: Sun, 13 Apr 2014 11:35:58 +0000 (+0200) Subject: More readable trapped rook condition X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=7bce8831d361317e0cf5156a888ca2d3e568a2ff;hp=81a8c1118beb4fd961423eec69dcb56d7518457d More readable trapped rook condition Prefer file_of(s) < file_of(ksq) to the inidrect file_of(ksq) < FILE_E To evaluate if semiopen side to check is the left side. Also other small touches while there. No functional change. --- diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 859a1c38..1d52d30c 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -379,10 +379,10 @@ namespace { } // Give a bonus for a rook on a open or semi-open file - if (ei.pi->semiopen(Us, file_of(s))) - score += ei.pi->semiopen(Them, file_of(s)) ? RookOpenFile : RookSemiopenFile; + if (ei.pi->semiopen_file(Us, file_of(s))) + score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOpenFile : RookSemiopenFile; - if (mob > 3 || ei.pi->semiopen(Us, file_of(s))) + if (mob > 3 || ei.pi->semiopen_file(Us, file_of(s))) continue; Square ksq = pos.king_square(Us); @@ -391,8 +391,8 @@ namespace { // king has lost its castling capability. if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) - && !ei.pi->semiopen_on_side(Us, file_of(ksq), file_of(ksq) < FILE_E)) - score -= (TrappedRook - make_score(mob * 8, 0)) * (pos.can_castle(Us) ? 1 : 2); + && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + score -= (TrappedRook - make_score(mob * 8, 0)) * (1 + !pos.can_castle(Us)); } // An important Chess960 pattern: A cornered bishop blocked by a friendly diff --git a/src/pawns.cpp b/src/pawns.cpp index 6d90f6b5..64c8e4b6 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -280,12 +280,11 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) { } -/// Entry::update_safety() calculates and caches a bonus for king safety. -/// It is called only when king square changes, which is about 20% of total -/// king_safety() calls. +/// Entry::do_king_safety() calculates a bonus for king safety. It is called only +/// when king square changes, which is about 20% of total king_safety() calls. template -Score Entry::update_safety(const Position& pos, Square ksq) { +Score Entry::do_king_safety(const Position& pos, Square ksq) { kingSquares[Us] = ksq; castlingRights[Us] = pos.can_castle(Us); @@ -296,7 +295,7 @@ Score Entry::update_safety(const Position& pos, Square ksq) { while (!(DistanceRingsBB[ksq][minKPdistance[Us]++] & pawns)) {} if (relative_rank(Us, ksq) > RANK_4) - return kingSafety[Us] = make_score(0, -16 * minKPdistance[Us]); + return make_score(0, -16 * minKPdistance[Us]); Value bonus = shelter_storm(pos, ksq); @@ -307,11 +306,11 @@ Score Entry::update_safety(const Position& pos, Square ksq) { if (pos.can_castle(MakeCastling::right)) bonus = std::max(bonus, shelter_storm(pos, relative_square(Us, SQ_C1))); - return kingSafety[Us] = make_score(bonus, -16 * minKPdistance[Us]); + return make_score(bonus, -16 * minKPdistance[Us]); } // Explicit template instantiation -template Score Entry::update_safety(const Position& pos, Square ksq); -template Score Entry::update_safety(const Position& pos, Square ksq); +template Score Entry::do_king_safety(const Position& pos, Square ksq); +template Score Entry::do_king_safety(const Position& pos, Square ksq); } // namespace Pawns diff --git a/src/pawns.h b/src/pawns.h index 525a6dcc..28fe1c07 100644 --- a/src/pawns.h +++ b/src/pawns.h @@ -26,11 +26,9 @@ namespace Pawns { -/// Pawns::Entry contains various information about a pawn structure. Currently, -/// it only includes a middlegame and endgame pawn structure evaluation, and a -/// bitboard of passed pawns. We may want to add further information in the future. -/// A lookup to the pawn hash table (performed by calling the probe function) -/// returns a pointer to an Entry object. +/// Pawns::Entry contains various information about a pawn structure. A lookup +/// to the pawn hash table (performed by calling the probe function) returns a +/// pointer to an Entry object. struct Entry { @@ -38,37 +36,42 @@ struct Entry { Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; } Bitboard passed_pawns(Color c) const { return passedPawns[c]; } Bitboard candidate_pawns(Color c) const { return candidatePawns[c]; } - int pawns_on_same_color_squares(Color c, Square s) const { return pawnsOnSquares[c][!!(DarkSquares & s)]; } - int semiopen(Color c, File f) const { return semiopenFiles[c] & (1 << int(f)); } - int semiopen_on_side(Color c, File f, bool left) const { - return semiopenFiles[c] & (left ? ((1 << int(f)) - 1) : ~((1 << int(f+1)) - 1)); + int semiopen_file(Color c, File f) const { + return semiopenFiles[c] & (1 << f); + } + + int semiopen_side(Color c, File f, bool leftSide) const { + return semiopenFiles[c] & (leftSide ? (1 << f) - 1 : ~((1 << (f + 1)) - 1)); + } + + int pawns_on_same_color_squares(Color c, Square s) const { + return pawnsOnSquares[c][!!(DarkSquares & s)]; } template Score king_safety(const Position& pos, Square ksq) { - - return kingSquares[Us] == ksq && castlingRights[Us] == pos.can_castle(Us) - ? kingSafety[Us] : update_safety(pos, ksq); + return kingSquares[Us] == ksq && castlingRights[Us] == pos.can_castle(Us) + ? kingSafety[Us] : (kingSafety[Us] = do_king_safety(pos, ksq)); } template - Score update_safety(const Position& pos, Square ksq); + Score do_king_safety(const Position& pos, Square ksq); template Value shelter_storm(const Position& pos, Square ksq); Key key; + Score value; Bitboard passedPawns[COLOR_NB]; Bitboard candidatePawns[COLOR_NB]; Bitboard pawnAttacks[COLOR_NB]; Square kingSquares[COLOR_NB]; + Score kingSafety[COLOR_NB]; int minKPdistance[COLOR_NB]; int castlingRights[COLOR_NB]; - Score value; int semiopenFiles[COLOR_NB]; - Score kingSafety[COLOR_NB]; - int pawnsOnSquares[COLOR_NB][COLOR_NB]; + int pawnsOnSquares[COLOR_NB][COLOR_NB]; // [color][light/dark squares] }; typedef HashTable Table; @@ -76,6 +79,6 @@ typedef HashTable Table; void init(); Entry* probe(const Position& pos, Table& entries); -} +} // namespace Pawns #endif // #ifndef PAWNS_H_INCLUDED