#define S(mg, eg) make_score(mg, eg)
// Isolated pawn penalty
- const Score Isolated = S(13, 18);
+ constexpr Score Isolated = S(13, 18);
// Backward pawn penalty
- const Score Backward = S(24, 12);
+ constexpr Score Backward = S(24, 12);
// Connected pawn bonus by opposed, phalanx, #support and rank
Score Connected[2][2][3][RANK_NB];
// Doubled pawn penalty
- const Score Doubled = S(18, 38);
+ constexpr Score Doubled = S(18, 38);
// Weakness of our pawn shelter in front of the king by [isKingFile][distance from edge][rank].
// RANK_1 = 0 is used for files where we have no pawns or our pawn is behind our king.
- const Value ShelterWeakness[][int(FILE_NB) / 2][RANK_NB] = {
+ constexpr Value ShelterWeakness[][int(FILE_NB) / 2][RANK_NB] = {
{ { V( 98), V(20), V(11), V(42), V( 83), V( 84), V(101) }, // Not On King file
{ V(103), V( 8), V(33), V(86), V( 87), V(105), V(113) },
{ V(100), V( 2), V(65), V(95), V( 59), V( 89), V(115) },
// Danger of enemy pawns moving toward our king by [type][distance from edge][rank].
// For the unopposed and unblocked cases, RANK_1 = 0 is used when opponent has
// no pawn on the given file, or their pawn is behind our king.
- const Value StormDanger[][4][RANK_NB] = {
+ constexpr Value StormDanger[][4][RANK_NB] = {
{ { V( 0), V(-290), V(-274), V(57), V(41) }, // BlockedByKing
{ V( 0), V( 60), V( 144), V(39), V(13) },
{ V( 0), V( 65), V( 141), V(41), V(34) },
{ V( 1), V( 64), V( 143), V(26), V(13) },
{ V( 1), V( 47), V( 110), V(44), V(24) },
{ V( 0), V( 72), V( 127), V(50), V(31) } },
- { { V( 0), V( 0), V( 79), V(23), V( 1) }, // BlockedByPawn
- { V( 0), V( 0), V( 148), V(27), V( 2) },
- { V( 0), V( 0), V( 161), V(16), V( 1) },
- { V( 0), V( 0), V( 171), V(22), V(15) } },
+ { { V( 0), V( 0), V( 19), V(23), V( 1) }, // BlockedByPawn
+ { V( 0), V( 0), V( 88), V(27), V( 2) },
+ { V( 0), V( 0), V( 101), V(16), V( 1) },
+ { V( 0), V( 0), V( 111), V(22), V(15) } },
{ { V(22), V( 45), V( 104), V(62), V( 6) }, // Unblocked
{ V(31), V( 30), V( 99), V(39), V(19) },
{ V(23), V( 29), V( 96), V(41), V(15) },
// Max bonus for king safety. Corresponds to start position with all the pawns
// in front of the king and no enemy pawn on the horizon.
- const Value MaxSafetyBonus = V(258);
+ constexpr Value MaxSafetyBonus = V(258);
#undef S
#undef V
template<Color Us>
Score evaluate(const Position& pos, Pawns::Entry* e) {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Direction Up = (Us == WHITE ? NORTH : SOUTH);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
Bitboard lever, leverPush;
// not attacked more times than defended.
if ( !(stoppers ^ lever ^ leverPush)
&& !(ourPawns & forward_file_bb(Us, s))
- && popcount(supported) >= popcount(lever)
+ && popcount(supported) >= popcount(lever) - 1
&& popcount(phalanx) >= popcount(leverPush))
e->passedPawns[Us] |= s;
e->passedPawns[Us] |= s;
}
- if (e->passedPawns[Us] & s)
- e->asymmetry++;
-
// Score this pawn
if (supported | phalanx)
score += Connected[opposed][bool(phalanx)][popcount(supported)][relative_rank(Us, s)];
void init() {
- static const int Seed[RANK_NB] = { 0, 13, 24, 18, 76, 100, 175, 330 };
+ static constexpr int Seed[RANK_NB] = { 0, 13, 24, 18, 76, 100, 175, 330 };
for (int opposed = 0; opposed <= 1; ++opposed)
for (int phalanx = 0; phalanx <= 1; ++phalanx)
return e;
e->key = key;
- e->asymmetry = 0;
e->scores[WHITE] = evaluate<WHITE>(pos, e);
e->scores[BLACK] = evaluate<BLACK>(pos, e);
- e->asymmetry += popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
- e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
+ e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
+ e->asymmetry = popcount( (e->passedPawns[WHITE] | e->passedPawns[BLACK])
+ | (e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]));
return e;
}
template<Color Us>
Value Entry::shelter_storm(const Position& pos, Square ksq) {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
enum { BlockedByKing, Unopposed, BlockedByPawn, Unblocked };
- Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq));
+ File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
+ Bitboard b = pos.pieces(PAWN)
+ & (forward_ranks_bb(Us, ksq) | rank_bb(ksq))
+ & (adjacent_files_bb(center) | file_bb(center));
Bitboard ourPawns = b & pos.pieces(Us);
Bitboard theirPawns = b & pos.pieces(Them);
Value safety = MaxSafetyBonus;
- File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
for (File f = File(center - 1); f <= File(center + 1); ++f)
{