/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008 Marco Costalba
+ Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+ Copyright (C) 2008-2009 Marco Costalba
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <cassert>
+#include "bitcount.h"
#include "movegen.h"
// Simple macro to wrap a very common while loop, no facny, no flexibility,
// hardcoded list name 'mlist' and from square 'from'.
#define SERIALIZE_MOVES(b) while (b) (*mlist++).move = make_move(from, pop_1st_bit(&b))
+// Version used for pawns, where the 'from' square is given as a delta from the 'to' square
+#define SERIALIZE_MOVES_D(b, d) while (b) { to = pop_1st_bit(&b); (*mlist++).move = make_move(to + (d), to); }
+
////
//// Local definitions
////
template<CastlingSide Side>
MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist);
- template<Color Us, Rank, Bitboard, SquareDelta>
+ template<Color Us>
MoveStack* generate_pawn_blocking_evasions(const Position&, Bitboard, Bitboard, MoveStack*);
- template<Color, Color, Bitboard, SquareDelta, SquareDelta, SquareDelta>
+ template<Color Us>
MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist);
- template<Color, Color, Bitboard, Bitboard, SquareDelta, SquareDelta, SquareDelta>
+ template<Color Us, SquareDelta Diagonal>
+ MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool promotion);
+
+ template<Color Us>
MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist);
- template<Color, Color, Bitboard, Bitboard, SquareDelta>
+ template<Color Us>
MoveStack* generate_pawn_checks(const Position&, Bitboard, Square, MoveStack*);
+ template<Color Us, SquareDelta Direction>
+ inline Bitboard move_pawns(Bitboard p) {
+
+ if (Direction == DELTA_N)
+ return Us == WHITE ? p << 8 : p >> 8;
+ else if (Direction == DELTA_NE)
+ return Us == WHITE ? p << 9 : p >> 7;
+ else if (Direction == DELTA_NW)
+ return Us == WHITE ? p << 7 : p >> 9;
+ else
+ return p;
+ }
+
// Template generate_piece_checks() with specializations
template<PieceType>
MoveStack* generate_piece_checks(const Position&, MoveStack*, Color, Bitboard, Square);
template<>
inline MoveStack* generate_piece_checks<PAWN>(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) {
- if (us == WHITE)
- return generate_pawn_checks<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_N>(p, dc, ksq, m);
- else
- return generate_pawn_checks<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_S>(p, dc, ksq, m);
-
+ return (us == WHITE ? generate_pawn_checks<WHITE>(p, dc, ksq, m)
+ : generate_pawn_checks<BLACK>(p, dc, ksq, m));
}
// Template generate_piece_moves() with specializations and overloads
assert(Piece == PAWN);
if (Type == CAPTURE)
- return (us == WHITE ? generate_pawn_captures<WHITE, BLACK, Rank8BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m)
- : generate_pawn_captures<BLACK, WHITE, Rank1BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m));
+ return (us == WHITE ? generate_pawn_captures<WHITE>(p, m)
+ : generate_pawn_captures<BLACK>(p, m));
else
- return (us == WHITE ? generate_pawn_noncaptures<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m)
- : generate_pawn_noncaptures<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m));
+ return (us == WHITE ? generate_pawn_noncaptures<WHITE>(p, m)
+ : generate_pawn_noncaptures<BLACK>(p, m));
}
template<PieceType>
template<>
inline MoveStack* generate_piece_moves<PAWN>(const Position& p, MoveStack* m,
Color us, Bitboard t, Bitboard pnd) {
- if (us == WHITE)
- return generate_pawn_blocking_evasions<WHITE, RANK_8, Rank3BB, DELTA_N>(p, pnd, t, m);
- else
- return generate_pawn_blocking_evasions<BLACK, RANK_1, Rank6BB, DELTA_S>(p, pnd, t, m);
+
+ return (us == WHITE ? generate_pawn_blocking_evasions<WHITE>(p, pnd, t, m)
+ : generate_pawn_blocking_evasions<BLACK>(p, pnd, t, m));
}
}
/// generate_captures generates() all pseudo-legal captures and queen
-/// promotions. The return value is the number of moves generated.
+/// promotions. The return value is the number of moves generated.
-int generate_captures(const Position& pos, MoveStack* mlist) {
+MoveStack* generate_captures(const Position& pos, MoveStack* mlist) {
assert(pos.is_ok());
assert(!pos.is_check());
Color us = pos.side_to_move();
Bitboard target = pos.pieces_of_color(opposite_color(us));
- MoveStack* mlist_start = mlist;
mlist = generate_piece_moves<QUEEN>(pos, mlist, us, target);
mlist = generate_piece_moves<ROOK>(pos, mlist, us, target);
mlist = generate_piece_moves<BISHOP>(pos, mlist, us, target);
mlist = generate_piece_moves<KNIGHT>(pos, mlist, us, target);
mlist = generate_piece_moves<PAWN, CAPTURE>(pos, mlist, us);
- mlist = generate_piece_moves<KING>(pos, mlist, us, target);
- return int(mlist - mlist_start);
+ return generate_piece_moves<KING>(pos, mlist, us, target);
}
/// generate_noncaptures() generates all pseudo-legal non-captures and
/// underpromotions. The return value is the number of moves generated.
-int generate_noncaptures(const Position& pos, MoveStack* mlist) {
+MoveStack* generate_noncaptures(const Position& pos, MoveStack* mlist) {
assert(pos.is_ok());
assert(!pos.is_check());
Color us = pos.side_to_move();
Bitboard target = pos.empty_squares();
- MoveStack* mlist_start = mlist;
mlist = generate_piece_moves<PAWN, NON_CAPTURE>(pos, mlist, us);
mlist = generate_piece_moves<KNIGHT>(pos, mlist, us, target);
mlist = generate_piece_moves<QUEEN>(pos, mlist, us, target);
mlist = generate_piece_moves<KING>(pos, mlist, us, target);
mlist = generate_castle_moves<KING_SIDE>(pos, mlist);
- mlist = generate_castle_moves<QUEEN_SIDE>(pos, mlist);
- return int(mlist - mlist_start);
+ return generate_castle_moves<QUEEN_SIDE>(pos, mlist);
}
-/// generate_checks() generates all pseudo-legal non-capturing, non-promoting
-/// checks. It returns the number of generated moves.
+/// generate_non_capture_checks() generates all pseudo-legal non-capturing,
+/// non-promoting checks. It returns the number of generated moves.
-int generate_checks(const Position& pos, MoveStack* mlist, Bitboard dc) {
+MoveStack* generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) {
assert(pos.is_ok());
assert(!pos.is_check());
Color us = pos.side_to_move();
Square ksq = pos.king_square(opposite_color(us));
- MoveStack* mlist_start = mlist;
- assert(pos.piece_on(ksq) == king_of_color(opposite_color(us)));
+ assert(pos.piece_on(ksq) == piece_of_color_and_type(opposite_color(us), KING));
// Pieces moves
mlist = generate_piece_checks<PAWN>(pos, mlist, us, dc, ksq);
&& castling_is_check(pos, KING_SIDE))
mlist = generate_castle_moves<KING_SIDE>(pos, mlist);
- return int(mlist - mlist_start);
+ return mlist;
}
/// in check. Unlike the other move generation functions, this one generates
/// only legal moves. It returns the number of generated moves.
-int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) {
+MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) {
assert(pos.is_ok());
assert(pos.is_check());
Color us = pos.side_to_move();
Color them = opposite_color(us);
Square ksq = pos.king_square(us);
- MoveStack* mlist_start = mlist;
- assert(pos.piece_on(ksq) == king_of_color(us));
+ assert(pos.piece_on(ksq) == piece_of_color_and_type(us, KING));
// The bitboard of occupied pieces without our king
Bitboard b_noKing = pos.occupied_squares();
}
}
}
- return int(mlist - mlist_start);
+ return mlist;
}
/// very hard to write an efficient legal move generator, but for the moment
/// we don't need it.
-int generate_legal_moves(const Position& pos, MoveStack* mlist) {
+MoveStack* generate_legal_moves(const Position& pos, MoveStack* mlist) {
assert(pos.is_ok());
return generate_evasions(pos, mlist, pinned);
// Generate pseudo-legal moves
- int n = generate_captures(pos, mlist);
- n += generate_noncaptures(pos, mlist + n);
+ MoveStack* last = generate_captures(pos, mlist);
+ last = generate_noncaptures(pos, last);
// Remove illegal moves from the list
- for (int i = 0; i < n; i++)
- if (!pos.pl_move_is_legal(mlist[i].move, pinned))
- mlist[i--].move = mlist[--n].move;
-
- return n;
+ for (MoveStack* cur = mlist; cur != last; cur++)
+ if (!pos.pl_move_is_legal(cur->move, pinned))
+ {
+ cur->move = (--last)->move;
+ cur--;
+ }
+ return last;
}
assert(pinned == pos.pinned_pieces(pos.side_to_move()));
Color us = pos.side_to_move();
- Color them = opposite_color(us);
Square from = move_from(m);
Piece pc = pos.piece_on(from);
if (color_of_piece(pc) != us)
return false;
+ Color them = opposite_color(us);
Square to = move_to(m);
// En passant moves
return false;
assert(pos.square_is_empty(to));
- assert(pos.piece_on(to - pawn_push(us)) == pawn_of_color(them));
+ assert(pos.piece_on(to - pawn_push(us)) == piece_of_color_and_type(them, PAWN));
// The move is pseudo-legal, check if it is also legal
return pos.pl_move_is_legal(m, pinned);
assert(from == pos.king_square(us));
assert(to == pos.initial_kr_square(us));
- assert(pos.piece_on(to) == rook_of_color(us));
+ assert(pos.piece_on(to) == piece_of_color_and_type(us, ROOK));
Square g1 = relative_square(us, SQ_G1);
Square f1 = relative_square(us, SQ_F1);
assert(from == pos.king_square(us));
assert(to == pos.initial_qr_square(us));
- assert(pos.piece_on(to) == rook_of_color(us));
+ assert(pos.piece_on(to) == piece_of_color_and_type(us, ROOK));
Square c1 = relative_square(us, SQ_C1);
Square d1 = relative_square(us, SQ_D1);
// Proceed according to the type of the moving piece.
if (type_of_piece(pc) == PAWN)
{
+ // Move direction must be compatible with pawn color
+ int direction = to - from;
+ if ((us == WHITE) != (direction > 0))
+ return false;
+
// If the destination square is on the 8/1th rank, the move must
// be a promotion.
if ( ( (square_rank(to) == RANK_8 && us == WHITE)
||(square_rank(to) == RANK_1 && us != WHITE))
- && !move_promotion(m))
+ && !move_is_promotion(m))
return false;
// Proceed according to the square delta between the source and
// destionation squares.
- switch (to - from)
+ switch (direction)
{
case DELTA_NW:
case DELTA_NE:
}
// Luckly we can handle all the other pieces in one go
- return ( pos.piece_attacks_square(from, to)
+ return ( pos.piece_attacks_square(pos.piece_on(from), from, to)
&& pos.pl_move_is_legal(m, pinned)
- && !move_promotion(m));
+ && !move_is_promotion(m));
+}
+
+
+/// Another version of move_is_legal(), which takes only a position and a move
+/// as input. This function does not require that the side to move is not in
+/// check. It is not optimized for speed, and is only used for verifying move
+/// legality when building a PV from the transposition table.
+
+bool move_is_legal(const Position& pos, const Move m) {
+
+ Bitboard pinned = pos.pinned_pieces(pos.side_to_move());
+ if (!pos.is_check())
+ return move_is_legal(pos, m, pinned);
+ else
+ {
+ Position p(pos);
+ MoveStack mlist[64];
+ MoveStack* last = generate_evasions(p, mlist, pinned);
+ for (MoveStack* cur = mlist; cur != last; cur++)
+ if (cur->move == m)
+ return true;
+
+ return false;
+ }
}
return mlist;
}
- template<Color Us, Color Them, Bitboard TRank8BB, SquareDelta TDELTA_NE,
- SquareDelta TDELTA_NW, SquareDelta TDELTA_N
- >
- MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) {
+ template<Color Us, SquareDelta Diagonal>
+ MoveStack* generate_pawn_captures_diagonal(MoveStack* mlist, Bitboard pawns, Bitboard enemyPieces, bool promotion) {
+
+ // Calculate our parametrized parameters at compile time
+ const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB);
+ const Bitboard TFileABB = (Diagonal == DELTA_NE ? FileABB : FileHBB);
+ const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE);
+ const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW);
+ const SquareDelta TTDELTA_NE = (Diagonal == DELTA_NE ? TDELTA_NE : TDELTA_NW);
Square to;
- Bitboard pawns = pos.pawns(Us);
- Bitboard enemyPieces = pos.pieces_of_color(Them);
- // Captures in the a1-h8 (a8-h1 for black) direction
- Bitboard b1 = (Us == WHITE ? pawns << 9 : pawns >> 7) & ~FileABB & enemyPieces;
+ // Captures in the a1-h8 (a8-h1 for black) diagonal or in the h1-a8 (h8-a1 for black)
+ Bitboard b1 = move_pawns<Us, Diagonal>(pawns) & ~TFileABB & enemyPieces;
// Capturing promotions
- Bitboard b2 = b1 & TRank8BB;
- while (b2)
+ if (promotion)
{
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, QUEEN);
+ Bitboard b2 = b1 & TRank8BB;
+ b1 &= ~TRank8BB;
+ while (b2)
+ {
+ to = pop_1st_bit(&b2);
+ (*mlist++).move = make_promotion_move(to - TTDELTA_NE, to, QUEEN);
+ }
}
// Capturing non-promotions
- b2 = b1 & ~TRank8BB;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_move(to - TDELTA_NE, to);
- }
+ SERIALIZE_MOVES_D(b1, -TTDELTA_NE);
+ return mlist;
+ }
- // Captures in the h1-a8 (h8-a1 for black) direction
- b1 = (Us == WHITE ? pawns << 7 : pawns >> 9) & ~FileHBB & enemyPieces;
+ template<Color Us>
+ MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) {
- // Capturing promotions
- b2 = b1 & TRank8BB;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, QUEEN);
- }
+ // Calculate our parametrized parameters at compile time
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB);
+ const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB);
+ const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S);
- // Capturing non-promotions
- b2 = b1 & ~TRank8BB;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_move(to - TDELTA_NW, to);
- }
+ Square to;
+ Bitboard pawns = pos.pawns(Us);
+ Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us));
+ bool possiblePromotion = (pawns & TRank7BB);
+
+ // Standard captures and capturing promotions in both directions
+ mlist = generate_pawn_captures_diagonal<Us, DELTA_NE>(mlist, pawns, enemyPieces, possiblePromotion);
+ mlist = generate_pawn_captures_diagonal<Us, DELTA_NW>(mlist, pawns, enemyPieces, possiblePromotion);
// Non-capturing promotions
- b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & pos.empty_squares() & TRank8BB;
- while (b1)
+ if (possiblePromotion)
{
- to = pop_1st_bit(&b1);
- (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN);
+ Bitboard b1 = move_pawns<Us, DELTA_N>(pawns) & pos.empty_squares() & TRank8BB;
+ while (b1)
+ {
+ to = pop_1st_bit(&b1);
+ (*mlist++).move = make_promotion_move(to - TDELTA_N, to, QUEEN);
+ }
}
// En passant captures
assert(Us != WHITE || square_rank(pos.ep_square()) == RANK_6);
assert(Us != BLACK || square_rank(pos.ep_square()) == RANK_3);
- b1 = pawns & pos.pawn_attacks(Them, pos.ep_square());
+ Bitboard b1 = pawns & pos.pawn_attacks(Them, pos.ep_square());
assert(b1 != EmptyBoardBB);
while (b1)
return mlist;
}
- template<Color Us, Color Them, Bitboard TRank8BB, Bitboard TRank3BB,
- SquareDelta TDELTA_NE, SquareDelta TDELTA_NW, SquareDelta TDELTA_N
- >
+ template<Color Us>
MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist) {
- Bitboard pawns = pos.pawns(Us);
- Bitboard enemyPieces = pos.pieces_of_color(Them);
- Bitboard emptySquares = pos.empty_squares();
+ // Calculate our parametrized parameters at compile time
+ const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB);
+ const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB);
+ const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
+ const SquareDelta TDELTA_NE = (Us == WHITE ? DELTA_NE : DELTA_SE);
+ const SquareDelta TDELTA_NW = (Us == WHITE ? DELTA_NW : DELTA_SW);
+ const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S);
+
Bitboard b1, b2;
Square to;
+ Bitboard pawns = pos.pawns(Us);
+ Bitboard emptySquares = pos.empty_squares();
- // Underpromotion captures in the a1-h8 (a8-h1 for black) direction
- b1 = (Us == WHITE ? pawns << 9 : pawns >> 7) & ~FileABB & enemyPieces & TRank8BB;
- while (b1)
+ if (pawns & TRank7BB) // There is some promotion candidate ?
{
- to = pop_1st_bit(&b1);
- (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, ROOK);
- (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, BISHOP);
- (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, KNIGHT);
- }
+ Bitboard enemyPieces = pos.pieces_of_color(opposite_color(Us));
- // Underpromotion captures in the h1-a8 (h8-a1 for black) direction
- b1 = (Us == WHITE ? pawns << 7 : pawns >> 9) & ~FileHBB & enemyPieces & TRank8BB;
- while (b1)
- {
- to = pop_1st_bit(&b1);
- (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, ROOK);
- (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, BISHOP);
- (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, KNIGHT);
+ // Underpromotion captures in the a1-h8 (a8-h1 for black) direction
+ b1 = move_pawns<Us, DELTA_NE>(pawns) & ~FileABB & enemyPieces & TRank8BB;
+ while (b1)
+ {
+ to = pop_1st_bit(&b1);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, ROOK);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, BISHOP);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NE, to, KNIGHT);
+ }
+
+ // Underpromotion captures in the h1-a8 (h8-a1 for black) direction
+ b1 = move_pawns<Us, DELTA_NW>(pawns) & ~FileHBB & enemyPieces & TRank8BB;
+ while (b1)
+ {
+ to = pop_1st_bit(&b1);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, ROOK);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, BISHOP);
+ (*mlist++).move = make_promotion_move(to - TDELTA_NW, to, KNIGHT);
+ }
+
+ // Underpromotion pawn pushes
+ b1 = move_pawns<Us, DELTA_N>(pawns) & emptySquares & TRank8BB;
+ while (b1)
+ {
+ to = pop_1st_bit(&b1);
+ (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK);
+ (*mlist++).move = make_promotion_move(to - TDELTA_N, to, BISHOP);
+ (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT);
+ }
}
// Single pawn pushes
- b1 = (Us == WHITE ? pawns << 8 : pawns >> 8) & emptySquares;
- b2 = b1 & TRank8BB;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_promotion_move(to - TDELTA_N, to, ROOK);
- (*mlist++).move = make_promotion_move(to - TDELTA_N, to, BISHOP);
- (*mlist++).move = make_promotion_move(to - TDELTA_N, to, KNIGHT);
- }
- b2 = b1 & ~TRank8BB;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_move(to - TDELTA_N, to);
- }
+ b2 = b1 = move_pawns<Us, DELTA_N>(pawns) & emptySquares & ~TRank8BB;
+ SERIALIZE_MOVES_D(b2, -TDELTA_N);
// Double pawn pushes
- b2 = (Us == WHITE ? (b1 & TRank3BB) << 8 : (b1 & TRank3BB) >> 8) & emptySquares;
- while (b2)
- {
- to = pop_1st_bit(&b2);
- (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to);
- }
+ b2 = move_pawns<Us, DELTA_N>(b1 & TRank3BB) & emptySquares;
+ SERIALIZE_MOVES_D(b2, -TDELTA_N -TDELTA_N);
return mlist;
}
- template<Color Us, Color Them, Bitboard TRank8BB, Bitboard TRank3BB, SquareDelta TDELTA_N>
+ template<Color Us>
MoveStack* generate_pawn_checks(const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist)
{
- // Find all friendly pawns not on the enemy king's file
+ // Calculate our parametrized parameters at compile time
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Bitboard TRank8BB = (Us == WHITE ? Rank8BB : Rank1BB);
+ const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
+ const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S);
+ const SquareDelta TDELTA_S = (Us == WHITE ? DELTA_S : DELTA_N);
+
+ Square to;
Bitboard b1, b2, b3;
- Bitboard empty = pos.empty_squares();
+ Bitboard pawns = pos.pawns(Us);
- if (dc != EmptyBoardBB)
+ if (dc & pawns)
{
+ Bitboard empty = pos.empty_squares();
+
// 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.
- b1 = pos.pawns(Us) & ~file_bb(ksq);
+ b1 = pawns & ~file_bb(ksq);
// Discovered checks, single pawn pushes, no promotions
- b2 = b3 = (Us == WHITE ? (b1 & dc) << 8 : (b1 & dc) >> 8) & empty & ~TRank8BB;
- while (b3)
- {
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N, to);
- }
+ b2 = b3 = move_pawns<Us, DELTA_N>(b1 & dc) & empty & ~TRank8BB;
+ SERIALIZE_MOVES_D(b3, -TDELTA_N);
// Discovered checks, double pawn pushes
- b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8) & empty;
- while (b3)
- {
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to);
- }
+ b3 = move_pawns<Us, DELTA_N>(b2 & TRank3BB) & empty;
+ SERIALIZE_MOVES_D(b3, -TDELTA_N -TDELTA_N);
}
// Direct checks. These are possible only for pawns on neighboring files
- // of the enemy king.
- b1 = pos.pawns(Us) & neighboring_files_bb(ksq) & ~dc;
+ // and in the two ranks that, after the push, are in front of the enemy king.
+ b1 = pawns & neighboring_files_bb(ksq) & ~dc;
+
+ // We can get false positives if (ksq + x) is not in [0,63] range but
+ // is not a problem, they will be filtered out later.
+ b2 = b1 & (rank_bb(ksq + 2 * TDELTA_S) | rank_bb(ksq + 3 * TDELTA_S));
+ if (!b2)
+ return mlist;
// Direct checks, single pawn pushes
- b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & empty;
+ Bitboard empty = pos.empty_squares();
+ b2 = move_pawns<Us, DELTA_N>(b1) & empty;
b3 = b2 & pos.pawn_attacks(Them, ksq);
- while (b3)
- {
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N, to);
- }
+ SERIALIZE_MOVES_D(b3, -TDELTA_N);
// Direct checks, double pawn pushes
- b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8)
- & empty
- & pos.pawn_attacks(Them, ksq);
- while (b3)
- {
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to);
- }
+ b3 = move_pawns<Us, DELTA_N>(b2 & TRank3BB) & empty & pos.pawn_attacks(Them, ksq);
+ SERIALIZE_MOVES_D(b3, -TDELTA_N -TDELTA_N);
return mlist;
}
// Direct checks
b = target & ~dc;
- if (Piece == KING || !b)
- return mlist;
-
- Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
- while (b)
+ if (Piece != KING || b)
{
- Square from = pop_1st_bit(&b);
- Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
- SERIALIZE_MOVES(bb);
+ Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
+ if (!checkSqs)
+ return mlist;
+
+ while (b)
+ {
+ Square from = pop_1st_bit(&b);
+ if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
+ || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs))
+ || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
+ continue;
+
+ Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
+ SERIALIZE_MOVES(bb);
+ }
}
return mlist;
}
- template<Color Us, Rank TRANK_8, Bitboard TRank3BB, SquareDelta TDELTA_N>
+ template<Color Us>
MoveStack* generate_pawn_blocking_evasions(const Position& pos, Bitboard pinned,
Bitboard blockSquares, MoveStack* mlist) {
+
+ // Calculate our parametrized parameters at compile time
+ const Rank TRANK_8 = (Us == WHITE ? RANK_8 : RANK_1);
+ const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
+ const SquareDelta TDELTA_N = (Us == WHITE ? DELTA_N : DELTA_S);
+
Square to;
- // Find non-pinned pawns
- Bitboard b1 = pos.pawns(Us) & ~pinned;
+ // Find non-pinned pawns and push them one square
+ Bitboard b1 = move_pawns<Us, DELTA_N>(pos.pawns(Us) & ~pinned);
- // Single pawn pushes. We don't have to AND with empty squares here,
+ // We don't have to AND with empty squares here,
// because the blocking squares will always be empty.
- Bitboard b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & blockSquares;
+ Bitboard b2 = b1 & blockSquares;
while (b2)
{
to = pop_1st_bit(&b2);
}
// Double pawn pushes
- b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & pos.empty_squares() & TRank3BB;
- b2 = (Us == WHITE ? b2 << 8 : b2 >> 8) & blockSquares;
+ b2 = b1 & pos.empty_squares() & TRank3BB;
+ b2 = move_pawns<Us, DELTA_N>(b2) & blockSquares;
while (b2)
{
to = pop_1st_bit(&b2);
Color them = opposite_color(us);
Square ksq = pos.king_square(us);
- assert(pos.piece_on(ksq) == king_of_color(us));
+ assert(pos.piece_on(ksq) == piece_of_color_and_type(us, KING));
Square rsq = (Side == KING_SIDE ? pos.initial_kr_square(us) : pos.initial_qr_square(us));
Square s1 = relative_square(us, Side == KING_SIDE ? SQ_G1 : SQ_C1);
Square s;
bool illegal = false;
- assert(pos.piece_on(rsq) == rook_of_color(us));
+ assert(pos.piece_on(rsq) == piece_of_color_and_type(us, ROOK));
// It is a bit complicated to correctly handle Chess960
for (s = Min(ksq, s1); s <= Max(ksq, s1); s++)
projects / stockfish / blobdiff