// check whether all moves end up in wins for the opponent
// if we are here, all captures are losing
static int check_loss(int *pcs, long64 idx0, ubyte *table, bitboard occ, int *p)
{
int sq;
long64 idx, idx2;
bitboard bb;
int best = LOSS_IN_ONE;
int k = *pcs++;
if (k == 0) { // white king
bb = WhiteKingMoves;
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove0(idx0, sq);
int v = win_loss[table[idx2]];
if (!v) return 0;
if (v < best) best = v;
ClearFirst(bb);
}
} else { // otherwise k == 1, i.e. black king
bb = BlackKingMoves;
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove1(idx0, sq);
int v = win_loss[table[idx2]];
if (!v) return 0;
if (v < best) best = v;
ClearFirst(bb);
}
}
while ((k = *pcs++) >= 0) {
bb = PieceMoves(p[k], pt[k], occ);
idx = idx0 & ~mask[k];
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove2(idx, k, sq);
int v = win_loss[table[idx2]];
if (!v) return 0;
if (v < best) best = v;
ClearFirst(bb);
}
}
return best;
}
// captures should be taken care of already
int check_mate_pieces(int *pcs, long64 idx0, ubyte *table, bitboard occ, int *p)
{
int sq;
long64 idx, idx2;
bitboard bb;
do {
int k = *pcs;
bb = PieceMoves(p[k], pt[k], occ);
idx = idx0 & ~mask[k];
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove(idx, k, sq);
if (table[idx2] < WDL_ILLEGAL) return 0;
ClearFirst(bb);
}
} while (*(++pcs) >= 0);
return 1;
}
static int check_mate(int *pcs, long64 idx0, ubyte *table, bitboard occ, int *p)
{
int sq;
long64 idx, idx2;
bitboard bb;
int k = *pcs++;
if (k == 0) { // white king
bb = WhiteKingMoves;
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove0(idx0, sq);
if (table[idx2] != ILLEGAL) return 0;
ClearFirst(bb);
}
} else { // otherwise k == 1, i.e. black king
bb = BlackKingMoves;
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove1(idx0, sq);
if (table[idx2] != ILLEGAL) return 0;
ClearFirst(bb);
}
}
while ((k = *pcs++) >= 0) {
bb = PieceMoves(p[k], pt[k], occ);
idx = idx0 & ~mask[k];
while (bb) {
sq = FirstOne(bb);
idx2 = MakeMove2(idx, k, sq);
if (table[idx2] != ILLEGAL) return 0;
ClearFirst(bb);
}
}
return 1;
}
