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https://github.com/sockspls/badfish
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Reshuffle stuff in movegen.cpp
No functional change. Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
parent
0026c88b3a
commit
cf247e7e30
1 changed files with 229 additions and 229 deletions
458
src/movegen.cpp
458
src/movegen.cpp
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@ -23,6 +23,7 @@
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#include "bitcount.h"
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#include "movegen.h"
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#include "position.h"
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#include "misc.h"
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// Simple macro to wrap a very common while loop, no facny, no flexibility,
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// hardcoded list name 'mlist' and from square 'from'.
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@ -33,16 +34,228 @@
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namespace {
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enum CastlingSide {
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KING_SIDE,
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QUEEN_SIDE
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};
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enum CastlingSide { KING_SIDE, QUEEN_SIDE };
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template<CastlingSide>
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MoveStack* generate_castle_moves(const Position&, MoveStack*, Color us);
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template<CastlingSide Side>
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MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist, Color us) {
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const CastleRight CR[] = { Side ? WHITE_OOO : WHITE_OO,
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Side ? BLACK_OOO : BLACK_OO };
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if (!pos.can_castle(CR[us]))
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return mlist;
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// After castling, the rook and king final positions are the same in Chess960
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// as they would be in standard chess.
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Square kfrom = pos.king_square(us);
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Square rfrom = pos.castle_rook_square(CR[us]);
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Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
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Square rto = relative_square(us, Side == KING_SIDE ? SQ_F1 : SQ_D1);
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Bitboard enemies = pos.pieces(flip(us));
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assert(!pos.in_check());
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assert(pos.piece_on(kfrom) == make_piece(us, KING));
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assert(pos.piece_on(rfrom) == make_piece(us, ROOK));
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// Unimpeded rule: All the squares between the king's initial and final squares
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// (including the final square), and all the squares between the rook's initial
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// and final squares (including the final square), must be vacant except for
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// the king and castling rook.
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for (Square s = std::min(rfrom, rto), e = std::max(rfrom, rto); s <= e; s++)
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if (s != kfrom && s != rfrom && !pos.square_is_empty(s))
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return mlist;
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for (Square s = std::min(kfrom, kto), e = std::max(kfrom, kto); s <= e; s++)
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if ( (s != kfrom && s != rfrom && !pos.square_is_empty(s))
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||(pos.attackers_to(s) & enemies))
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return mlist;
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// Because we generate only legal castling moves we need to verify that
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// when moving the castling rook we do not discover some hidden checker.
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// For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
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if (pos.is_chess960())
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{
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Bitboard occ = pos.occupied_squares();
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clear_bit(&occ, rfrom);
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if (pos.attackers_to(kto, occ) & enemies)
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return mlist;
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}
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(*mlist++).move = make_castle(kfrom, rfrom);
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return mlist;
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}
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template<Square Delta>
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inline Bitboard move_pawns(Bitboard p) {
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return Delta == DELTA_N ? p << 8 : Delta == DELTA_S ? p >> 8 :
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Delta == DELTA_NE ? p << 9 : Delta == DELTA_SE ? p >> 7 :
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Delta == DELTA_NW ? p << 7 : Delta == DELTA_SW ? p >> 9 : p;
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}
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template<Square Delta>
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inline MoveStack* generate_pawn_captures(MoveStack* mlist, Bitboard pawns, Bitboard target) {
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const Bitboard EdgeFileBB = ( Delta == DELTA_NE
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|| Delta == DELTA_SE ? FileABB : FileHBB);
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Bitboard b;
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Square to;
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b = move_pawns<Delta>(pawns) & target & ~EdgeFileBB;
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SERIALIZE_MOVES_D(b, -Delta);
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return mlist;
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}
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template<MoveType Type, Square Delta>
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inline MoveStack* generate_promotions(const Position& pos, MoveStack* mlist, Bitboard pawnsOn7, Bitboard target) {
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const Bitboard EdgeFileBB = ( Delta == DELTA_NE
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|| Delta == DELTA_SE ? FileABB : FileHBB);
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Bitboard b;
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Square to;
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b = move_pawns<Delta>(pawnsOn7) & target;
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if (Delta != DELTA_N && Delta != DELTA_S)
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b &= ~EdgeFileBB;
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while (b)
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{
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to = pop_1st_bit(&b);
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if (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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(*mlist++).move = make_promotion(to - Delta, to, QUEEN);
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if (Type == MV_NON_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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{
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(*mlist++).move = make_promotion(to - Delta, to, ROOK);
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(*mlist++).move = make_promotion(to - Delta, to, BISHOP);
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(*mlist++).move = make_promotion(to - Delta, to, KNIGHT);
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}
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// Knight under promotion is the only one that can give a check not
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// already included in the queen-promotion.
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if (Type == MV_CHECK)
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{
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Square ksq = pos.king_square(Delta > 0 ? BLACK : WHITE);
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if (bit_is_set(pos.attacks_from<KNIGHT>(to), ksq))
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(*mlist++).move = make_promotion(to - Delta, to, KNIGHT);
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}
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else
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(void)pos; // Silence a warning under MSVC
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}
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return mlist;
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}
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template<Color Us, MoveType Type>
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MoveStack* generate_pawn_moves(const Position& pos, MoveStack* mlist, Bitboard target, Square ksq) {
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// Calculate our parametrized parameters at compile time, named
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// according to the point of view of white side.
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const Color Them = (Us == WHITE ? BLACK : WHITE);
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const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB);
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const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
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const Square UP = (Us == WHITE ? DELTA_N : DELTA_S);
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const Square RIGHT_UP = (Us == WHITE ? DELTA_NE : DELTA_SW);
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const Square LEFT_UP = (Us == WHITE ? DELTA_NW : DELTA_SE);
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Square to;
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Bitboard b1, b2, dc1, dc2, pawnPushes, emptySquares;
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Bitboard pawns = pos.pieces(PAWN, Us);
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Bitboard pawnsOn7 = pawns & TRank7BB;
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Bitboard enemyPieces = (Type == MV_CAPTURE ? target : pos.pieces(Them));
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// Pre-calculate pawn pushes before changing emptySquares definition
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if (Type != MV_CAPTURE)
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{
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emptySquares = (Type == MV_NON_CAPTURE ? target : pos.empty_squares());
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pawnPushes = move_pawns<UP>(pawns & ~TRank7BB) & emptySquares;
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}
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if (Type == MV_EVASION)
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{
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emptySquares &= target; // Only blocking squares
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enemyPieces &= target; // Capture only the checker piece
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}
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// Promotions and underpromotions
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if (pawnsOn7)
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{
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if (Type == MV_CAPTURE)
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emptySquares = pos.empty_squares();
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pawns &= ~TRank7BB;
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mlist = generate_promotions<Type, RIGHT_UP>(pos, mlist, pawnsOn7, enemyPieces);
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mlist = generate_promotions<Type, LEFT_UP>(pos, mlist, pawnsOn7, enemyPieces);
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mlist = generate_promotions<Type, UP>(pos, mlist, pawnsOn7, emptySquares);
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}
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// Standard captures
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if (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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{
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mlist = generate_pawn_captures<RIGHT_UP>(mlist, pawns, enemyPieces);
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mlist = generate_pawn_captures<LEFT_UP>(mlist, pawns, enemyPieces);
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}
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// Single and double pawn pushes
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if (Type != MV_CAPTURE)
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{
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b1 = (Type != MV_EVASION ? pawnPushes : pawnPushes & emptySquares);
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b2 = move_pawns<UP>(pawnPushes & TRank3BB) & emptySquares;
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if (Type == MV_CHECK)
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{
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// Consider only pawn moves which give direct checks
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b1 &= pos.attacks_from<PAWN>(ksq, Them);
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b2 &= pos.attacks_from<PAWN>(ksq, Them);
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// Add pawn moves which gives discovered check. This is possible only
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// if the pawn is not on the same file as the enemy king, because we
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// don't generate captures.
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if (pawns & target) // For CHECK type target is dc bitboard
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{
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dc1 = move_pawns<UP>(pawns & target & ~file_bb(ksq)) & emptySquares;
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dc2 = move_pawns<UP>(dc1 & TRank3BB) & emptySquares;
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b1 |= dc1;
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b2 |= dc2;
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}
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}
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SERIALIZE_MOVES_D(b1, -UP);
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SERIALIZE_MOVES_D(b2, -UP -UP);
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}
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// En passant captures
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if ( (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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&& pos.ep_square() != SQ_NONE)
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{
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assert(Us != WHITE || rank_of(pos.ep_square()) == RANK_6);
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assert(Us != BLACK || rank_of(pos.ep_square()) == RANK_3);
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// An en passant capture can be an evasion only if the checking piece
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// is the double pushed pawn and so is in the target. Otherwise this
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// is a discovery check and we are forced to do otherwise.
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if (Type == MV_EVASION && !bit_is_set(target, pos.ep_square() - UP))
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return mlist;
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b1 = pawns & pos.attacks_from<PAWN>(pos.ep_square(), Them);
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assert(b1);
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while (b1)
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{
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to = pop_1st_bit(&b1);
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(*mlist++).move = make_enpassant(to, pos.ep_square());
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}
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}
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return mlist;
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}
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template<Color, MoveType>
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MoveStack* generate_pawn_moves(const Position&, MoveStack*, Bitboard, Square);
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template<PieceType Pt>
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inline MoveStack* generate_discovered_checks(const Position& pos, MoveStack* mlist, Square from) {
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@ -58,6 +271,7 @@ namespace {
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return mlist;
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}
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template<PieceType Pt>
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inline MoveStack* generate_direct_checks(const Position& pos, MoveStack* mlist, Color us,
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Bitboard dc, Square ksq) {
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@ -90,6 +304,7 @@ namespace {
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return mlist;
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}
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template<>
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FORCE_INLINE MoveStack* generate_direct_checks<PAWN>(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) {
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@ -97,6 +312,7 @@ namespace {
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: generate_pawn_moves<BLACK, MV_CHECK>(p, m, dc, ksq));
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}
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template<PieceType Pt, MoveType Type>
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FORCE_INLINE MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us, Bitboard t) {
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@ -105,6 +321,7 @@ namespace {
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: generate_pawn_moves<BLACK, Type>(p, m, t, SQ_NONE));
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}
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template<PieceType Pt>
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FORCE_INLINE MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) {
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@ -123,6 +340,7 @@ namespace {
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return mlist;
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}
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template<>
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FORCE_INLINE MoveStack* generate_piece_moves<KING>(const Position& pos, MoveStack* mlist, Color us, Bitboard target) {
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@ -134,7 +352,7 @@ namespace {
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return mlist;
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}
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}
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} // namespace
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/// generate<MV_CAPTURE> generates all pseudo-legal captures and queen
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@ -173,11 +391,8 @@ MoveStack* generate(const Position& pos, MoveStack* mlist) {
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if (Type != MV_CAPTURE && pos.can_castle(us))
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{
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if (pos.can_castle(us == WHITE ? WHITE_OO : BLACK_OO))
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mlist = generate_castle_moves<KING_SIDE>(pos, mlist, us);
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if (pos.can_castle(us == WHITE ? WHITE_OOO : BLACK_OOO))
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mlist = generate_castle_moves<QUEEN_SIDE>(pos, mlist, us);
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mlist = generate_castle_moves<KING_SIDE>(pos, mlist, us);
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mlist = generate_castle_moves<QUEEN_SIDE>(pos, mlist, us);
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}
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return mlist;
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@ -320,218 +535,3 @@ MoveStack* generate<MV_LEGAL>(const Position& pos, MoveStack* mlist) {
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return last;
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}
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namespace {
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template<Square Delta>
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inline Bitboard move_pawns(Bitboard p) {
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return Delta == DELTA_N ? p << 8 : Delta == DELTA_S ? p >> 8 :
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Delta == DELTA_NE ? p << 9 : Delta == DELTA_SE ? p >> 7 :
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Delta == DELTA_NW ? p << 7 : Delta == DELTA_SW ? p >> 9 : p;
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}
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template<Square Delta>
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inline MoveStack* generate_pawn_captures(MoveStack* mlist, Bitboard pawns, Bitboard target) {
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const Bitboard TFileABB = (Delta == DELTA_NE || Delta == DELTA_SE ? FileABB : FileHBB);
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Bitboard b;
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Square to;
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// Captures in the a1-h8 (a8-h1 for black) diagonal or in the h1-a8 (h8-a1 for black)
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b = move_pawns<Delta>(pawns) & target & ~TFileABB;
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SERIALIZE_MOVES_D(b, -Delta);
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return mlist;
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}
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template<MoveType Type, Square Delta>
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inline MoveStack* generate_promotions(const Position& pos, MoveStack* mlist, Bitboard pawnsOn7, Bitboard target) {
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const Bitboard TFileABB = (Delta == DELTA_NE || Delta == DELTA_SE ? FileABB : FileHBB);
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Bitboard b;
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Square to;
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// Promotions and under-promotions, both captures and non-captures
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b = move_pawns<Delta>(pawnsOn7) & target;
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if (Delta != DELTA_N && Delta != DELTA_S)
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b &= ~TFileABB;
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while (b)
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{
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to = pop_1st_bit(&b);
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if (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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(*mlist++).move = make_promotion(to - Delta, to, QUEEN);
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if (Type == MV_NON_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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{
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(*mlist++).move = make_promotion(to - Delta, to, ROOK);
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(*mlist++).move = make_promotion(to - Delta, to, BISHOP);
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(*mlist++).move = make_promotion(to - Delta, to, KNIGHT);
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}
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// This is the only possible under promotion that can give a check
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// not already included in the queen-promotion.
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if ( Type == MV_CHECK
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&& bit_is_set(pos.attacks_from<KNIGHT>(to), pos.king_square(Delta > 0 ? BLACK : WHITE)))
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(*mlist++).move = make_promotion(to - Delta, to, KNIGHT);
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else (void)pos; // Silence a warning under MSVC
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}
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return mlist;
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}
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template<Color Us, MoveType Type>
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MoveStack* generate_pawn_moves(const Position& pos, MoveStack* mlist, Bitboard target, Square ksq) {
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// Calculate our parametrized parameters at compile time, named
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// according to the point of view of white side.
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const Color Them = (Us == WHITE ? BLACK : WHITE);
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const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB);
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const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
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const Square UP = (Us == WHITE ? DELTA_N : DELTA_S);
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const Square RIGHT_UP = (Us == WHITE ? DELTA_NE : DELTA_SW);
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const Square LEFT_UP = (Us == WHITE ? DELTA_NW : DELTA_SE);
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Square to;
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Bitboard b1, b2, dc1, dc2, pawnPushes, emptySquares;
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Bitboard pawns = pos.pieces(PAWN, Us);
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Bitboard pawnsOn7 = pawns & TRank7BB;
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Bitboard enemyPieces = (Type == MV_CAPTURE ? target : pos.pieces(Them));
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// Pre-calculate pawn pushes before changing emptySquares definition
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if (Type != MV_CAPTURE)
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{
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emptySquares = (Type == MV_NON_CAPTURE ? target : pos.empty_squares());
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pawnPushes = move_pawns<UP>(pawns & ~TRank7BB) & emptySquares;
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}
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if (Type == MV_EVASION)
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{
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emptySquares &= target; // Only blocking squares
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enemyPieces &= target; // Capture only the checker piece
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}
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// Promotions and underpromotions
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if (pawnsOn7)
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{
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if (Type == MV_CAPTURE)
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emptySquares = pos.empty_squares();
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pawns &= ~TRank7BB;
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mlist = generate_promotions<Type, RIGHT_UP>(pos, mlist, pawnsOn7, enemyPieces);
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mlist = generate_promotions<Type, LEFT_UP>(pos, mlist, pawnsOn7, enemyPieces);
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mlist = generate_promotions<Type, UP>(pos, mlist, pawnsOn7, emptySquares);
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}
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// Standard captures
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if (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
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{
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mlist = generate_pawn_captures<RIGHT_UP>(mlist, pawns, enemyPieces);
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mlist = generate_pawn_captures<LEFT_UP>(mlist, pawns, enemyPieces);
|
||||
}
|
||||
|
||||
// Single and double pawn pushes
|
||||
if (Type != MV_CAPTURE)
|
||||
{
|
||||
b1 = (Type != MV_EVASION ? pawnPushes : pawnPushes & emptySquares);
|
||||
b2 = move_pawns<UP>(pawnPushes & TRank3BB) & emptySquares;
|
||||
|
||||
if (Type == MV_CHECK)
|
||||
{
|
||||
// Consider only pawn moves which give direct checks
|
||||
b1 &= pos.attacks_from<PAWN>(ksq, Them);
|
||||
b2 &= pos.attacks_from<PAWN>(ksq, Them);
|
||||
|
||||
// Add pawn moves which gives discovered check. This is possible only
|
||||
// if the pawn is not on the same file as the enemy king, because we
|
||||
// don't generate captures.
|
||||
if (pawns & target) // For CHECK type target is dc bitboard
|
||||
{
|
||||
dc1 = move_pawns<UP>(pawns & target & ~file_bb(ksq)) & emptySquares;
|
||||
dc2 = move_pawns<UP>(dc1 & TRank3BB) & emptySquares;
|
||||
|
||||
b1 |= dc1;
|
||||
b2 |= dc2;
|
||||
}
|
||||
}
|
||||
SERIALIZE_MOVES_D(b1, -UP);
|
||||
SERIALIZE_MOVES_D(b2, -UP -UP);
|
||||
}
|
||||
|
||||
// En passant captures
|
||||
if ( (Type == MV_CAPTURE || Type == MV_EVASION || Type == MV_NON_EVASION)
|
||||
&& pos.ep_square() != SQ_NONE)
|
||||
{
|
||||
assert(Us != WHITE || rank_of(pos.ep_square()) == RANK_6);
|
||||
assert(Us != BLACK || rank_of(pos.ep_square()) == RANK_3);
|
||||
|
||||
// An en passant capture can be an evasion only if the checking piece
|
||||
// is the double pushed pawn and so is in the target. Otherwise this
|
||||
// is a discovery check and we are forced to do otherwise.
|
||||
if (Type == MV_EVASION && !bit_is_set(target, pos.ep_square() - UP))
|
||||
return mlist;
|
||||
|
||||
b1 = pawns & pos.attacks_from<PAWN>(pos.ep_square(), Them);
|
||||
|
||||
assert(b1);
|
||||
|
||||
while (b1)
|
||||
{
|
||||
to = pop_1st_bit(&b1);
|
||||
(*mlist++).move = make_enpassant(to, pos.ep_square());
|
||||
}
|
||||
}
|
||||
return mlist;
|
||||
}
|
||||
|
||||
template<CastlingSide Side>
|
||||
MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist, Color us) {
|
||||
|
||||
CastleRight f = CastleRight((Side == KING_SIDE ? WHITE_OO : WHITE_OOO) << us);
|
||||
Color them = flip(us);
|
||||
|
||||
// After castling, the rook and king's final positions are exactly the same
|
||||
// in Chess960 as they would be in standard chess.
|
||||
Square kfrom = pos.king_square(us);
|
||||
Square rfrom = pos.castle_rook_square(f);
|
||||
Square kto = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
|
||||
Square rto = relative_square(us, Side == KING_SIDE ? SQ_F1 : SQ_D1);
|
||||
|
||||
assert(!pos.in_check());
|
||||
assert(pos.piece_on(kfrom) == make_piece(us, KING));
|
||||
assert(pos.piece_on(rfrom) == make_piece(us, ROOK));
|
||||
|
||||
// Unimpeded rule: All the squares between the king's initial and final squares
|
||||
// (including the final square), and all the squares between the rook's initial
|
||||
// and final squares (including the final square), must be vacant except for
|
||||
// the king and castling rook.
|
||||
for (Square s = std::min(kfrom, kto); s <= std::max(kfrom, kto); s++)
|
||||
if ( (s != kfrom && s != rfrom && !pos.square_is_empty(s))
|
||||
||(pos.attackers_to(s) & pos.pieces(them)))
|
||||
return mlist;
|
||||
|
||||
for (Square s = std::min(rfrom, rto); s <= std::max(rfrom, rto); s++)
|
||||
if (s != kfrom && s != rfrom && !pos.square_is_empty(s))
|
||||
return mlist;
|
||||
|
||||
// Because we generate only legal castling moves we need to verify that
|
||||
// when moving the castling rook we do not discover some hidden checker.
|
||||
// For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
|
||||
if (pos.is_chess960())
|
||||
{
|
||||
Bitboard occ = pos.occupied_squares();
|
||||
clear_bit(&occ, rfrom);
|
||||
if (pos.attackers_to(kto, occ) & pos.pieces(them))
|
||||
return mlist;
|
||||
}
|
||||
|
||||
(*mlist++).move = make_castle(kfrom, rfrom);
|
||||
|
||||
return mlist;
|
||||
}
|
||||
|
||||
} // namespace
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue