////
namespace {
+
+ inline Bitboard forward_white(Bitboard b) { return b << 8; }
+ inline Bitboard forward_right_white(Bitboard b) { return b << 9; }
+ inline Bitboard forward_left_white(Bitboard b) { return b << 7; }
+
+ inline Bitboard forward_black(Bitboard b) { return b >> 8; }
+ inline Bitboard forward_right_black(Bitboard b) { return b >> 7; }
+ inline Bitboard forward_left_black(Bitboard b) { return b >> 9; }
+
+ struct PawnOffsets {
+
+ Bitboard Rank3BB, Rank8BB;
+ SquareDelta DELTA_N, DELTA_NE, DELTA_NW;
+ Color us, them;
+ typedef Bitboard (*Shift_fn)(Bitboard b);
+ Shift_fn forward, forward_left, forward_right;
+ };
+ const PawnOffsets WhitePawnOffsets = { Rank3BB, Rank8BB, DELTA_N, DELTA_NE, DELTA_NW, WHITE,
+ BLACK, &forward_white, forward_left_white, forward_right_white };
+
+ const PawnOffsets BlackPawnOffsets = { Rank6BB, Rank1BB, DELTA_S, DELTA_SE, DELTA_SW, BLACK,
+ WHITE, &forward_black, &forward_left_black, &forward_right_black };
- int generate_white_pawn_captures(const Position&, MoveStack*);
- int generate_black_pawn_captures(const Position&, MoveStack*);
+ int generate_pawn_captures(const PawnOffsets& ofs, const Position& pos, MoveStack* mlist);
int generate_white_pawn_noncaptures(const Position&, MoveStack*);
int generate_black_pawn_noncaptures(const Position&, MoveStack*);
int generate_piece_moves(PieceType, const Position&, MoveStack*, Color side, Bitboard t);
int generate_piece_checks(PieceType pce, const Position& pos, Bitboard target,
Bitboard dc, Square ksq, MoveStack* mlist, int n);
- inline Bitboard next_row_white(Bitboard b) { return b << 8; }
- inline Bitboard next_row_black(Bitboard b) { return b >> 8; }
-
- struct PawnOffsets {
-
- Bitboard Rank3BB;
- Bitboard Rank8BB;
- SquareDelta DELTA_N;
- Color them;
- Bitboard (*next_row_fn)(Bitboard b);
- };
- const PawnOffsets WhitePawnOffsets = { Rank3BB, Rank8BB, DELTA_N, BLACK, &next_row_white };
- const PawnOffsets BlackPawnOffsets = { Rank6BB, Rank1BB, DELTA_S, WHITE, &next_row_black };
-
int generate_pawn_checks(const PawnOffsets& ofs, const Position& pos, Bitboard dc,
Square ksq, MoveStack* mlist, int n);
}
int n;
if (us == WHITE)
- n = generate_white_pawn_captures(pos, mlist);
+ n = generate_pawn_captures(WhitePawnOffsets, pos, mlist);
else
- n = generate_black_pawn_captures(pos, mlist);
+ n = generate_pawn_captures(BlackPawnOffsets, pos, mlist);
for (PieceType pce = KNIGHT; pce <= KING; pce++)
n += generate_piece_moves(pce, pos, mlist+n, us, target);
assert(pos.is_ok());
assert(!pos.is_check());
+ int n;
Color us = pos.side_to_move();
Square ksq = pos.king_square(opposite_color(us));
- int n = 0;
assert(pos.piece_on(ksq) == king_of_color(opposite_color(us)));
namespace {
- int generate_white_pawn_captures(const Position &pos, MoveStack *mlist) {
+ int generate_pawn_captures(const PawnOffsets& ofs, const Position& pos, MoveStack* mlist) {
- Bitboard pawns = pos.pawns(WHITE);
- Bitboard enemyPieces = pos.pieces_of_color(BLACK);
+ Bitboard pawns = pos.pawns(ofs.us);
+ Bitboard enemyPieces = pos.pieces_of_color(ofs.them);
Square sq;
int n = 0;
- // Captures in the a1-h8 direction
- Bitboard b1 = (pawns << 9) & ~FileABB & enemyPieces;
+ // Captures in the a1-h8 (a8-h1 for black) direction
+ Bitboard b1 = (ofs.forward_right)(pawns) & ~FileABB & enemyPieces;
// Capturing promotions
- Bitboard b2 = b1 & Rank8BB;
+ Bitboard b2 = b1 & ofs.Rank8BB;
while (b2)
{
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_NE, sq, QUEEN);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NE, sq, QUEEN);
}
// Capturing non-promotions
- b2 = b1 & ~Rank8BB;
+ b2 = b1 & ~ofs.Rank8BB;
while (b2)
{
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_NE, sq);
+ mlist[n++].move = make_move(sq - ofs.DELTA_NE, sq);
}
- // Captures in the h1-a8 direction
- b1 = (pawns << 7) & ~FileHBB & enemyPieces;
+ // Captures in the h1-a8 (h8-a1 for black) direction
+ b1 = (ofs.forward_left)(pawns) & ~FileHBB & enemyPieces;
// Capturing promotions
- b2 = b1 & Rank8BB;
+ b2 = b1 & ofs.Rank8BB;
while (b2)
{
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_NW, sq, QUEEN);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NW, sq, QUEEN);
}
// Capturing non-promotions
- b2 = b1 & ~Rank8BB;
+ b2 = b1 & ~ofs.Rank8BB;
while (b2)
{
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_NW, sq);
+ mlist[n++].move = make_move(sq - ofs.DELTA_NW, sq);
}
// Non-capturing promotions
- b1 = (pawns << 8) & pos.empty_squares() & Rank8BB;
+ b1 = (ofs.forward)(pawns) & pos.empty_squares() & Rank8BB;
while (b1)
{
sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_N, sq, QUEEN);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_N, sq, QUEEN);
}
// En passant captures
if (pos.ep_square() != SQ_NONE)
{
- assert(square_rank(pos.ep_square()) == RANK_6);
- b1 = pawns & pos.black_pawn_attacks(pos.ep_square());
- assert(b1 != EmptyBoardBB);
- while (b1)
- {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_ep_move(sq, pos.ep_square());
- }
- }
- return n;
- }
+ assert(ofs.us != WHITE || square_rank(pos.ep_square()) == RANK_6);
+ assert(ofs.us != BLACK || square_rank(pos.ep_square()) == RANK_3);
-
- int generate_black_pawn_captures(const Position &pos, MoveStack *mlist) {
-
- Bitboard pawns = pos.pawns(BLACK);
- Bitboard enemyPieces = pos.pieces_of_color(WHITE);
- Square sq;
- int n = 0;
-
- // Captures in the a8-h1 direction
- Bitboard b1 = (pawns >> 7) & ~FileABB & enemyPieces;
-
- // Capturing promotions
- Bitboard b2 = b1 & Rank1BB;
- while (b2)
- {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_SE, sq, QUEEN);
- }
-
- // Capturing non-promotions
- b2 = b1 & ~Rank1BB;
- while (b2)
- {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_SE, sq);
- }
-
- // Captures in the h8-a1 direction
- b1 = (pawns >> 9) & ~FileHBB & enemyPieces;
-
- // Capturing promotions
- b2 = b1 & Rank1BB;
- while (b2)
- {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_SW, sq, QUEEN);
- }
-
- // Capturing Non-promotions
- b2 = b1 & ~Rank1BB;
- while (b2)
- {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_SW, sq);
- }
-
- // Non-capturing promotions
- b1 = (pawns >> 8) & pos.empty_squares() & Rank1BB;
- while (b1)
- {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_S, sq, QUEEN);
- }
-
- // En passant captures
- if (pos.ep_square() != SQ_NONE)
- {
- assert(square_rank(pos.ep_square()) == RANK_3);
- b1 = pawns & pos.white_pawn_attacks(pos.ep_square());
+ b1 = pawns & pos.pawn_attacks(ofs.them, pos.ep_square());
assert(b1 != EmptyBoardBB);
+
while (b1)
{
sq = pop_1st_bit(&b1);
Bitboard b1 = pos.pawns(pos.side_to_move()) & ~file_bb(ksq), b2, b3;
// Discovered checks, single pawn pushes
- b2 = b3 = (ofs.next_row_fn)(b1 & dc) & ~ofs.Rank8BB & empty;
+ b2 = b3 = (ofs.forward)(b1 & dc) & ~ofs.Rank8BB & empty;
while (b3)
{
Square to = pop_1st_bit(&b3);
}
// Discovered checks, double pawn pushes
- b3 = (ofs.next_row_fn)(b2 & ofs.Rank3BB) & empty;
+ b3 = (ofs.forward)(b2 & ofs.Rank3BB) & empty;
while (b3)
{
Square to = pop_1st_bit(&b3);
b1 &= (~dc & neighboring_files_bb(ksq)); // FIXME why ~dc ??
// Direct checks, single pawn pushes
- b2 = (ofs.next_row_fn)(b1) & empty;
+ b2 = (ofs.forward)(b1) & empty;
b3 = b2 & pos.pawn_attacks(ofs.them, ksq);
while (b3)
{
}
// Direct checks, double pawn pushes
- b3 = (ofs.next_row_fn)(b2 & ofs.Rank3BB) & empty & pos.pawn_attacks(ofs.them, ksq);
+ b3 = (ofs.forward)(b2 & ofs.Rank3BB) & empty & pos.pawn_attacks(ofs.them, ksq);
while (b3)
{
Square to = pop_1st_bit(&b3);