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move-gen: separate pawn capture from en-passant (easier later testing)

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Bruno Raoult
2024-03-18 09:13:51 +01:00
parent 9c2e76442d
commit 748953a767
1 changed files with 18 additions and 9 deletions
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27
src/move-gen.c
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@@ -79,7 +79,7 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
* 5th relative rank. To do so, we create an occupation bb without
* the 2 pawns.
*/
if (is_capture(move) && PIECE(pos->board[to]) == EMPTY) {
if (is_enpassant(move)) {
/* from rank bitboard */
bitboard_t rank5 = bb_sqrank[from];
/* enemy rooks/queens on from rank */
@@ -158,6 +158,7 @@ movelist_t *pos_all_legal(const pos_t *pos, movelist_t *dest)
* When immediately known, a few move flags are also applied in these cases:
* - castling: M_CASTLE_{K,Q}
* - pawn capture (incl. en-passant): M_CAPTURE
* en-passant: M_EN_PASSANT
* - promotion: M_PROMOTION
* - promotion and capture
*
@@ -188,7 +189,7 @@ int pos_gen_pseudomoves(pos_t *pos)
/* king - MUST BE FIRST ! */
from = pos->king[us];
movebits = bb_king_moves(not_my_pieces, from);
bit_for_each64(to, tmp2, movebits) {
bit_for_each64(to, tmp1, movebits) {
moves[nmoves++] = move_make(from, to);
}
if (popcount64(pos->checkers) > 1) /* double check, we stop here */
@@ -235,8 +236,6 @@ int pos_gen_pseudomoves(pos_t *pos)
// sizeof(RANK_3bb));
//bitboard_t rel_filea = (me == WHITE ? FILE_Abb : FILE_Hbb);
//bitboard_t rel_fileh = (me == WHITE ? FILE_Hbb : FILE_Abb);
int en_passant = pos->en_passant == SQUARE_NONE? 0: pos->en_passant;
bitboard_t enemy_avail = bb_sq[en_passant] | enemy_pieces;
/* pawn: ranks 2-6 push 1 and 2 squares */
movebits = pawn_shift_up(pos->bb[us][PAWN] & ~rel_rank7, us) & empty;
@@ -252,21 +251,31 @@ int pos_gen_pseudomoves(pos_t *pos)
moves[nmoves++] = move_make(from, to);
}
/* pawn: ranks 2-6 captures left, including en-passant */
/* pawn: ranks 2-6 captures left */
from_pawns = pos->bb[us][PAWN] & ~rel_rank7; // & ~rel_filea;
movebits = pawn_shift_upleft(from_pawns, us) & enemy_avail;
movebits = pawn_shift_upleft(from_pawns, us) & enemy_pieces;
bit_for_each64(to, tmp1, movebits) {
from = pawn_push_upleft(to, them); /* reverse capture */
moves[nmoves++] = move_make_capture(from, to);
}
/* pawn: ranks 2-6 captures right, including en-passant */
/* pawn: ranks 2-6 captures right */
from_pawns = pos->bb[us][PAWN] & ~rel_rank7; // & ~rel_fileh;
movebits = pawn_shift_upright(from_pawns, us) & enemy_avail;
movebits = pawn_shift_upright(from_pawns, us) & enemy_pieces;
bit_for_each64(to, tmp1, movebits) {
from = pawn_push_upright(to, them);
moves[nmoves++] = move_make_capture(from, to);
}
/* pawn: en-passant */
if ((to = pos->en_passant) != SQUARE_NONE) {
movebits = mask(to);
from_pawns = pos->bb[us][PAWN]
& (pawn_shift_upleft(movebits, them) | pawn_shift_upright(movebits, them));
bit_for_each64(from, tmp1, from_pawns) {
moves[nmoves++] = move_make_enpassant(from, to);
}
}
/* pawn: rank 7 push */
movebits = pawn_shift_up(pos->bb[us][PAWN] & rel_rank7, us) & empty;
bit_for_each64(to, tmp1, movebits) {
@@ -278,7 +287,7 @@ int pos_gen_pseudomoves(pos_t *pos)
}
/* pawn promotion: rank 7 captures left */
from_pawns = pos->bb[us][PAWN] & rel_rank7; // & ~rel_filea;
movebits = pawn_shift_upleft(from_pawns, us) & enemy_avail;
movebits = pawn_shift_upleft(from_pawns, us) & enemy_pieces;
bit_for_each64(to, tmp1, movebits) {
from = pawn_push_upleft(to, them); /* reverse capture */
moves[nmoves++] = move_make_promote_capture(from, to, QUEEN);