////
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_white_pawn_noncaptures(const Position&, MoveStack*);
- int generate_black_pawn_noncaptures(const Position&, MoveStack*);
+ int generate_pawn_captures(const PawnOffsets&, const Position&, MoveStack*);
+ int generate_pawn_noncaptures(const PawnOffsets&, const Position&, MoveStack*);
+ int generate_pawn_checks(const PawnOffsets&, const Position&, Bitboard dc, Square ksq, MoveStack*, int n);
int generate_piece_moves(PieceType, const Position&, MoveStack*, Color side, Bitboard t);
int generate_castle_moves(const Position&, MoveStack*, Color us);
int generate_piece_checks(PieceType pce, const Position& pos, Bitboard target,
- Bitboard dc, Square ksq, MoveStack* mlist);
+ 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);
int n;
if (us == WHITE)
- n = generate_white_pawn_noncaptures(pos, mlist);
+ n = generate_pawn_noncaptures(WhitePawnOffsets, pos, mlist);
else
- n = generate_black_pawn_noncaptures(pos, mlist);
+ n = generate_pawn_noncaptures(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());
- Color us, them;
- Square ksq, from, to;
- Bitboard empty, b1, b2, b3;
- int n = 0;
-
- us = pos.side_to_move();
- them = opposite_color(us);
+ int n;
+ Color us = pos.side_to_move();
+ Square ksq = pos.king_square(opposite_color(us));
- ksq = pos.king_square(them);
- assert(pos.piece_on(ksq) == king_of_color(them));
+ assert(pos.piece_on(ksq) == king_of_color(opposite_color(us)));
dc = pos.discovered_check_candidates(us);
- empty = pos.empty_squares();
-
- // Pawn moves. This is somewhat messy, and we use separate code for white
- // and black, because we can't shift by negative numbers in C/C++. :-(
-
- if (us == WHITE)
- {
- // Pawn moves which give 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.
-
- // Find all friendly pawns not on the enemy king's file
- b1 = pos.pawns(us) & ~file_bb(ksq);
-
- // Discovered checks, single pawn pushes
- b2 = b3 = ((b1 & dc) << 8) & ~Rank8BB & empty;
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_N, to);
- }
-
- // Discovered checks, double pawn pushes
- b3 = ((b2 & Rank3BB) << 8) & empty;
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_N - DELTA_N, to);
- }
-
- // Direct checks. These are possible only for pawns on neighboring files
- // of the enemy king
-
- b1 &= (~dc & neighboring_files_bb(ksq)); // FIXME why ~dc ??
-
- // Direct checks, single pawn pushes
- b2 = (b1 << 8) & empty;
- b3 = b2 & pos.pawn_attacks(BLACK, ksq);
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_N, to);
- }
-
- // Direct checks, double pawn pushes
- b3 = ((b2 & Rank3BB) << 8) & empty & pos.pawn_attacks(BLACK, ksq);
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_N - DELTA_N, to);
- }
- }
- else { // (us == BLACK)
- // Pawn moves which give 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.
-
- // Find all friendly pawns not on the enemy king's file:
- b1 = pos.pawns(us) & ~file_bb(ksq);
-
- // Discovered checks, single pawn pushes
- b2 = b3 = ((b1 & dc) >> 8) & ~Rank1BB & empty;
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_S, to);
- }
-
- // Discovered checks, double pawn pushes
- b3 = ((b2 & Rank6BB) >> 8) & empty;
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_S - DELTA_S, to);
- }
-
- // Direct checks. These are possible only for pawns on neighboring files
- // of the enemy king
-
- b1 &= (~dc & neighboring_files_bb(ksq));
-
- // Direct checks, single pawn pushes:
- b2 = (b1 >> 8) & empty;
- b3 = b2 & pos.pawn_attacks(WHITE, ksq);
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_S, to);
- }
-
- // Direct checks, double pawn pushes
- b3 = ((b2 & Rank6BB) >> 8) & empty & pos.pawn_attacks(WHITE, ksq);
- while (b3)
- {
- to = pop_1st_bit(&b3);
- mlist[n++].move = make_move(to - DELTA_S - DELTA_S, to);
- }
- }
+ // Pawn moves
+ if (us == WHITE)
+ n = generate_pawn_checks(WhitePawnOffsets, pos, dc, ksq, mlist, 0);
+ else
+ n = generate_pawn_checks(BlackPawnOffsets, pos, dc, ksq, mlist, 0);
- // Knight moves
- b1 = pos.knights(us);
- if (b1)
- n += generate_piece_checks(KNIGHT, pos, b1, dc, ksq, mlist);
+ // Pieces moves
+ Bitboard b = pos.knights(us);
+ if (b)
+ n = generate_piece_checks(KNIGHT, pos, b, dc, ksq, mlist, n);
- // Bishop moves
- b1 = pos.bishops(us);
- if (b1)
- n += generate_piece_checks(BISHOP, pos, b1, dc, ksq, mlist);
+ b = pos.bishops(us);
+ if (b)
+ n = generate_piece_checks(BISHOP, pos, b, dc, ksq, mlist, n);
- // Rook moves
- b1 = pos.rooks(us);
- if (b1)
- n += generate_piece_checks(ROOK, pos, b1, dc, ksq, mlist);
+ b = pos.rooks(us);
+ if (b)
+ n = generate_piece_checks(ROOK, pos, b, dc, ksq, mlist, n);
- // Queen moves
- b1 = pos.queens(us);
- if (b1)
- n += generate_piece_checks(QUEEN, pos, b1, dc, ksq, mlist);
+ b = pos.queens(us);
+ if (b)
+ n = generate_piece_checks(QUEEN, pos, b, dc, ksq, mlist, n);
// King moves
- from = pos.king_square(us);
+ Square from = pos.king_square(us);
if (bit_is_set(dc, from))
{
- b1 = pos.king_attacks(from) & empty & ~QueenPseudoAttacks[ksq];
- while (b1)
+ b = pos.king_attacks(from) & pos.empty_squares() & ~QueenPseudoAttacks[ksq];
+ while (b)
{
- to = pop_1st_bit(&b1);
+ Square to = pop_1st_bit(&b);
mlist[n++].move = make_move(from, to);
}
}
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(ofs.us != WHITE || square_rank(pos.ep_square()) == RANK_6);
+ assert(ofs.us != BLACK || square_rank(pos.ep_square()) == RANK_3);
+
+ b1 = pawns & pos.pawn_attacks(ofs.them, pos.ep_square());
assert(b1 != EmptyBoardBB);
+
while (b1)
{
sq = pop_1st_bit(&b1);
}
- int generate_black_pawn_captures(const Position &pos, MoveStack *mlist) {
+ int generate_pawn_noncaptures(const PawnOffsets& ofs, const Position& pos, MoveStack* mlist) {
- Bitboard pawns = pos.pawns(BLACK);
- Bitboard enemyPieces = pos.pieces_of_color(WHITE);
+ Bitboard pawns = pos.pawns(ofs.us);
+ Bitboard enemyPieces = pos.pieces_of_color(ofs.them);
+ Bitboard emptySquares = pos.empty_squares();
+ Bitboard b1, b2;
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)
+ // Underpromotion captures in the a1-h8 (a8-h1 for black) direction
+ b1 = ofs.forward_right(pawns) & ~FileABB & enemyPieces & ofs.Rank8BB;
+ while (b1)
{
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_SE, sq, QUEEN);
+ sq = pop_1st_bit(&b1);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NE, sq, ROOK);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NE, sq, BISHOP);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NE, sq, KNIGHT);
}
- // Capturing non-promotions
- b2 = b1 & ~Rank1BB;
- while (b2)
+ // Underpromotion captures in the h1-a8 (h8-a1 for black) direction
+ b1 = ofs.forward_left(pawns) & ~FileHBB & enemyPieces & ofs.Rank8BB;
+ while (b1)
{
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_SE, sq);
+ sq = pop_1st_bit(&b1);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NW, sq, ROOK);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NW, sq, BISHOP);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_NW, sq, KNIGHT);
}
- // Captures in the h8-a1 direction
- b1 = (pawns >> 9) & ~FileHBB & enemyPieces;
-
- // Capturing promotions
- b2 = b1 & Rank1BB;
+ // Single pawn pushes
+ b1 = ofs.forward(pawns) & emptySquares;
+ b2 = b1 & ofs.Rank8BB;
while (b2)
{
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_SW, sq, QUEEN);
+ sq = pop_1st_bit(&b2);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_N, sq, ROOK);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_N, sq, BISHOP);
+ mlist[n++].move = make_promotion_move(sq - ofs.DELTA_N, sq, KNIGHT);
}
-
- // Capturing Non-promotions
- b2 = b1 & ~Rank1BB;
+ b2 = b1 & ~ofs.Rank8BB;
while (b2)
{
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_SW, sq);
+ mlist[n++].move = make_move(sq - ofs.DELTA_N, 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)
+ // Double pawn pushes
+ b2 = (ofs.forward(b1 & ofs.Rank3BB)) & emptySquares;
+ while (b2)
{
- assert(square_rank(pos.ep_square()) == RANK_3);
- b1 = pawns & pos.white_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;
- }
-
-
- int generate_white_pawn_noncaptures(const Position &pos, MoveStack *mlist) {
-
- Bitboard pawns = pos.pawns(WHITE);
- Bitboard enemyPieces = pos.pieces_of_color(BLACK);
- Bitboard emptySquares = pos.empty_squares();
- Bitboard b1, b2;
- Square sq;
- int n = 0;
-
- // Underpromotion captures in the a1-h8 direction:
- b1 = (pawns << 9) & ~FileABB & enemyPieces & Rank8BB;
- while(b1) {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_NE, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_NE, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_NE, sq, KNIGHT);
- }
-
- // Underpromotion captures in the h1-a8 direction:
- b1 = (pawns << 7) & ~FileHBB & enemyPieces & Rank8BB;
- while(b1) {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_NW, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_NW, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_NW, sq, KNIGHT);
- }
-
- // Single pawn pushes:
- b1 = (pawns << 8) & emptySquares;
- b2 = b1 & Rank8BB;
- while(b2) {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_N, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_N, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_N, sq, KNIGHT);
- }
- b2 = b1 & ~Rank8BB;
- while(b2) {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_N, sq);
- }
-
- // Double pawn pushes:
- b2 = ((b1 & Rank3BB) << 8) & emptySquares;
- while(b2) {
sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_N - DELTA_N, sq);
+ mlist[n++].move = make_move(sq - ofs.DELTA_N - ofs.DELTA_N, sq);
}
-
- return n;
- }
-
-
- int generate_black_pawn_noncaptures(const Position &pos, MoveStack *mlist) {
- Bitboard pawns = pos.pawns(BLACK);
- Bitboard enemyPieces = pos.pieces_of_color(WHITE);
- Bitboard emptySquares = pos.empty_squares();
- Bitboard b1, b2;
- Square sq;
- int n = 0;
-
- // Underpromotion captures in the a8-h1 direction:
- b1 = (pawns >> 7) & ~FileABB & enemyPieces & Rank1BB;
- while(b1) {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_SE, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_SE, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_SE, sq, KNIGHT);
- }
-
- // Underpromotion captures in the h8-a1 direction:
- b1 = (pawns >> 9) & ~FileHBB & enemyPieces & Rank1BB;
- while(b1) {
- sq = pop_1st_bit(&b1);
- mlist[n++].move = make_promotion_move(sq - DELTA_SW, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_SW, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_SW, sq, KNIGHT);
- }
-
- // Single pawn pushes:
- b1 = (pawns >> 8) & emptySquares;
- b2 = b1 & Rank1BB;
- while(b2) {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_promotion_move(sq - DELTA_S, sq, ROOK);
- mlist[n++].move = make_promotion_move(sq - DELTA_S, sq, BISHOP);
- mlist[n++].move = make_promotion_move(sq - DELTA_S, sq, KNIGHT);
- }
- b2 = b1 & ~Rank1BB;
- while(b2) {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_S, sq);
- }
-
- // Double pawn pushes:
- b2 = ((b1 & Rank6BB) >> 8) & emptySquares;
- while(b2) {
- sq = pop_1st_bit(&b2);
- mlist[n++].move = make_move(sq - DELTA_S - DELTA_S, sq);
- }
-
return n;
}
}
int generate_piece_checks(PieceType pce, const Position& pos, Bitboard target,
- Bitboard dc, Square ksq, MoveStack* mlist) {
+ Bitboard dc, Square ksq, MoveStack* mlist, int n) {
const Piece_attacks_fn mem_fn = piece_attacks_fn[pce];
- int n = 0;
// Discovered checks
Bitboard b = target & dc;
}
return n;
}
+
+ int generate_pawn_checks(const PawnOffsets& ofs, const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist, int n)
+ {
+ // Pawn moves which give 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.
+ Bitboard empty = pos.empty_squares();
+
+ // Find all friendly pawns not on the enemy king's file
+ Bitboard b1 = pos.pawns(pos.side_to_move()) & ~file_bb(ksq), b2, b3;
+
+ // Discovered checks, single pawn pushes
+ b2 = b3 = (ofs.forward)(b1 & dc) & ~ofs.Rank8BB & empty;
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ mlist[n++].move = make_move(to - ofs.DELTA_N, to);
+ }
+
+ // Discovered checks, double pawn pushes
+ b3 = (ofs.forward)(b2 & ofs.Rank3BB) & empty;
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ mlist[n++].move = make_move(to - ofs.DELTA_N - ofs.DELTA_N, to);
+ }
+
+ // Direct checks. These are possible only for pawns on neighboring files
+ // of the enemy king
+
+ b1 &= (~dc & neighboring_files_bb(ksq)); // FIXME why ~dc ??
+
+ // Direct checks, single pawn pushes
+ b2 = (ofs.forward)(b1) & empty;
+ b3 = b2 & pos.pawn_attacks(ofs.them, ksq);
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ mlist[n++].move = make_move(to - ofs.DELTA_N, to);
+ }
+
+ // Direct checks, double pawn pushes
+ b3 = (ofs.forward)(b2 & ofs.Rank3BB) & empty & pos.pawn_attacks(ofs.them, ksq);
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ mlist[n++].move = make_move(to - ofs.DELTA_N - ofs.DELTA_N, to);
+ }
+ return n;
+ }
}