Reduce of one instruction. It seems a tad faster on
the profiler now. Very slightly but anyhow it is a
code semplification.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
// Locate the least valuable attacker for the side to move. The loop
// below looks like it is potentially infinite, but it isn't. We know
// that the side to move still has at least one attacker left.
// Locate the least valuable attacker for the side to move. The loop
// below looks like it is potentially infinite, but it isn't. We know
// that the side to move still has at least one attacker left.
- for (pt = PAWN; !(stmAttackers & pieces(pt)); pt++)
+ for (pt = PAWN; (b = stmAttackers & pieces(pt)) == 0; pt++)
assert(pt < KING);
// Remove the attacker we just found from the 'occupied' bitboard,
// and scan for new X-ray attacks behind the attacker.
assert(pt < KING);
// Remove the attacker we just found from the 'occupied' bitboard,
// and scan for new X-ray attacks behind the attacker.
- b = stmAttackers & pieces(pt);
occ ^= (b & (~b + 1));
attackers |= (attacks_bb<ROOK>(to, occ) & pieces(ROOK, QUEEN))
| (attacks_bb<BISHOP>(to, occ) & pieces(BISHOP, QUEEN));
occ ^= (b & (~b + 1));
attackers |= (attacks_bb<ROOK>(to, occ) & pieces(ROOK, QUEEN))
| (attacks_bb<BISHOP>(to, occ) & pieces(BISHOP, QUEEN));