kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-07-13 04:29:15 +00:00
Code Issues Releases Wiki Activity

Reformat eval_init()

Browse source 
Move more code into eval_init, removing some
clutter in the main routine.

Write eval_init only from "our" point of view
(do not init the attackedBy[Them] bitboards).

Add mobilityArea to the evalinfo

A few edits while being there

tested for non-regression at STC
http://tests.stockfishchess.org/tests/view/587fab230ebc5915193f77d9
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 39585 W: 7183 L: 7094 D: 25308

Non functional change.
This commit is contained in:
Alain SAVARD 2017-01-17 21:40:31 -05:00 • committed by Marco Costalba
parent 9f8f093fd6
commit 243a9f5484
1 changed files with 63 additions and 65 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

128
src/evaluate.cpp
View file

@ -73,6 +73,11 @@ namespace {
// by the evaluation functions.
struct EvalInfo {
Material::Entry* me;
Pawns::Entry* pe;
Bitboard pinnedPieces[COLOR_NB];
Bitboard mobilityArea[COLOR_NB];
// attackedBy[color][piece type] is a bitboard representing all squares
// attacked by a given color and piece type (can be also ALL_PIECES).
Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
@ -106,17 +111,13 @@ namespace {
// a white knight on g5 and black's king is on g8, this white knight adds 2
// to kingAdjacentZoneAttacksCount[WHITE].
int kingAdjacentZoneAttacksCount[COLOR_NB];
Bitboard pinnedPieces[COLOR_NB];
Material::Entry* me;
Pawns::Entry* pi;
};
#define V(v) Value(v)
#define S(mg, eg) make_score(mg, eg)
// MobilityBonus[PieceType][attacked] contains bonuses for middle and end
// game, indexed by piece type and number of attacked squares in the MobilityArea.
// MobilityBonus[PieceType][attacked] contains bonuses for middle and end game,
// indexed by piece type and number of attacked squares in the mobility area.
const Score MobilityBonus[][32] = {
{}, {},
{ S(-75,-76), S(-56,-54), S( -9,-26), S( -2,-10), S( 6, 5), S( 15, 11), // Knights
@ -231,23 +232,35 @@ namespace {
void eval_init(const Position& pos, EvalInfo& ei) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
const Square Up = (Us == WHITE ? NORTH : SOUTH);
const Square Down = (Us == WHITE ? SOUTH : NORTH);
const Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB);
ei.pinnedPieces[Us] = pos.pinned_pieces(Us);
Bitboard b = ei.attackedBy[Them][KING];
ei.attackedBy[Them][ALL_PIECES] |= b;
ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
ei.attackedBy2[Us] = ei.attackedBy[Us][PAWN] & ei.attackedBy[Us][KING];
// Init king safety tables only if we are going to use them
if (pos.non_pawn_material(Us) >= QueenValueMg)
// Find our pawns on the first two ranks, and those which are blocked
Bitboard b = pos.pieces(Us, PAWN) & (shift<Down>(pos.pieces()) | LowRanks);
// Squares occupied by those pawns, by our king, or controlled by enemy pawns
// are excluded from the mobility area.
ei.mobilityArea[Us] = ~(b | pos.square<KING>(Us) | ei.pe->pawn_attacks(Them));
// Initialise the attack bitboards with the king and pawn information
b = ei.attackedBy[Us][KING] = pos.attacks_from<KING>(pos.square<KING>(Us));
ei.attackedBy[Us][PAWN] = ei.pe->pawn_attacks(Us);
ei.attackedBy2[Us] = b & ei.attackedBy[Us][PAWN];
ei.attackedBy[Us][ALL_PIECES] = b | ei.attackedBy[Us][PAWN];
// Init our king safety tables only if we are going to use them
if (pos.non_pawn_material(Them) >= QueenValueMg)
{
ei.kingRing[Them] = b | shift<Down>(b);
ei.kingAttackersCount[Us] = popcount(b & ei.attackedBy[Us][PAWN]);
ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0;
ei.kingRing[Us] = b | shift<Up>(b);
ei.kingAttackersCount[Them] = popcount(b & ei.pe->pawn_attacks(Them));
ei.kingAdjacentZoneAttacksCount[Them] = ei.kingAttackersWeight[Them] = 0;
}
else
ei.kingRing[Them] = ei.kingAttackersCount[Us] = 0;
ei.kingRing[Us] = ei.kingAttackersCount[Them] = 0;
}
@ -255,8 +268,8 @@ namespace {
// color and type.
template<bool DoTrace, Color Us = WHITE, PieceType Pt = KNIGHT>
Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility,
const Bitboard* mobilityArea) {
Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility) {
const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1));
const Color Them = (Us == WHITE ? BLACK : WHITE);
const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
@ -294,14 +307,14 @@ namespace {
| ei.attackedBy[Them][BISHOP]
| ei.attackedBy[Them][ROOK]);
int mob = popcount(b & mobilityArea[Us]);
int mob = popcount(b & ei.mobilityArea[Us]);
mobility[Us] += MobilityBonus[Pt][mob];
if (Pt == BISHOP || Pt == KNIGHT)
{
// Bonus for outpost squares
bb = OutpostRanks & ~ei.pi->pawn_attacks_span(Them);
bb = OutpostRanks & ~ei.pe->pawn_attacks_span(Them);
if (bb & s)
score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)];
else
@ -318,7 +331,7 @@ namespace {
// Penalty for pawns on the same color square as the bishop
if (Pt == BISHOP)
score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s);
score -= BishopPawns * ei.pe->pawns_on_same_color_squares(Us, s);
// An important Chess960 pattern: A cornered bishop blocked by a friendly
// pawn diagonally in front of it is a very serious problem, especially
@ -342,16 +355,16 @@ namespace {
score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]);
// Bonus when on an open or semi-open file
if (ei.pi->semiopen_file(Us, file_of(s)))
score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))];
if (ei.pe->semiopen_file(Us, file_of(s)))
score += RookOnFile[!!ei.pe->semiopen_file(Them, file_of(s))];
// Penalize when trapped by the king, even more if the king cannot castle
// Penalty when trapped by the king, even more if the king cannot castle
else if (mob <= 3)
{
Square ksq = pos.square<KING>(Us);
if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq)))
&& !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq)))
&& !ei.pe->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq)))
score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us));
}
}
@ -369,13 +382,13 @@ namespace {
Trace::add(Pt, Us, score);
// Recursively call evaluate_pieces() of next piece type until KING is excluded
return score - evaluate_pieces<DoTrace, Them, NextPt>(pos, ei, mobility, mobilityArea);
return score - evaluate_pieces<DoTrace, Them, NextPt>(pos, ei, mobility);
}
template<>
Score evaluate_pieces<false, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; }
Score evaluate_pieces<false, WHITE, KING>(const Position&, EvalInfo&, Score*) { return SCORE_ZERO; }
template<>
Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; }
Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*) { return SCORE_ZERO; }
// evaluate_king() assigns bonuses and penalties to a king of a given color
@ -400,12 +413,12 @@ namespace {
int kingDanger;
// King shelter and enemy pawns storm
Score score = ei.pi->king_safety<Us>(pos, ksq);
Score score = ei.pe->king_safety<Us>(pos, ksq);
// Main king safety evaluation
if (ei.kingAttackersCount[Them])
{
// Find the attacked squares which are defended only by the king...
// Find the attacked squares which are defended only by our king...
undefended = ei.attackedBy[Them][ALL_PIECES]
& ei.attackedBy[Us][KING]
& ~ei.attackedBy2[Us];
@ -427,20 +440,15 @@ namespace {
- 7 * mg_value(score) / 5 - 5;
// Analyse the enemy's safe queen contact checks. Firstly, find the
// undefended squares around the king reachable by the enemy queen...
// undefended squares around our king reachable by the enemy queen...
b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them);
// ...and keep squares supported by another enemy piece
// ...and keep squares supported by another enemy piece.
kingDanger += QueenContactCheck * popcount(b & ei.attackedBy2[Them]);
// Analyse the safe enemy's checks which are possible on next move...
// Analyse the safe enemy's checks which are possible on next move
safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them));
// ... and some other potential checks, only requiring the square to be
// safe from pawn-attacks, and not being occupied by a blocked pawn.
other = ~( ei.attackedBy[Us][PAWN]
| (pos.pieces(Them, PAWN) & shift<Up>(pos.pieces(PAWN))));
b1 = pos.attacks_from<ROOK >(ksq);
b2 = pos.attacks_from<BISHOP>(ksq);
@ -448,12 +456,18 @@ namespace {
if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe)
kingDanger += QueenCheck;
// For other pieces, also consider the square safe if attacked twice,
// and only defended by a queen.
// For minors and rooks, also consider the square safe if attacked twice,
// and only defended by our queen.
safe |= ei.attackedBy2[Them]
& ~(ei.attackedBy2[Us] | pos.pieces(Them))
& ei.attackedBy[Us][QUEEN];
// Some other potential checks are also analysed, even from squares
// currently occupied by the opponent own pieces, as long as the square
// is not attacked by our pawns, and is not occupied by a blocked pawn.
other = ~( ei.attackedBy[Us][PAWN]
| (pos.pieces(Them, PAWN) & shift<Up>(pos.pieces(PAWN))));
// Enemy rooks safe and other checks
if (b1 & ei.attackedBy[Them][ROOK] & safe)
kingDanger += RookCheck;
@ -476,7 +490,7 @@ namespace {
else if (b & other)
score -= OtherCheck;
// Compute the king danger score and subtract it from the evaluation
// Transform the kingDanger units into a Score, and substract it from the evaluation
if (kingDanger > 0)
score -= make_score(std::min(kingDanger * kingDanger / 4096, 2 * int(BishopValueMg)), 0);
}
@ -611,7 +625,7 @@ namespace {
Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares;
Score score = SCORE_ZERO;
b = ei.pi->passed_pawns(Us);
b = ei.pe->passed_pawns(Us);
while (b)
{
@ -719,10 +733,10 @@ namespace {
// Since SpaceMask[Us] is fully on our half of the board...
assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0);
// ...count safe + (behind & safe) with a single popcount
// ...count safe + (behind & safe) with a single popcount.
int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe));
bonus = std::min(16, bonus);
int weight = pos.count<ALL_PIECES>(Us) - 2 * ei.pi->open_files();
int weight = pos.count<ALL_PIECES>(Us) - 2 * ei.pe->open_files();
return make_score(bonus * weight * weight / 18, 0);
}
@ -824,8 +838,8 @@ Value Eval::evaluate(const Position& pos) {
Score score = pos.psq_score() + ei.me->imbalance();
// Probe the pawn hash table
ei.pi = Pawns::probe(pos);
score += ei.pi->pawns_score();
ei.pe = Pawns::probe(pos);
score += ei.pe->pawns_score();
// We have taken into account all cheap evaluation terms.
// If score exceeds a threshold return a lazy evaluation.
@ -834,27 +848,11 @@ Value Eval::evaluate(const Position& pos) {
return pos.side_to_move() == WHITE ? lazy : -lazy;
// Initialize attack and king safety bitboards
ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0;
ei.attackedBy[WHITE][KING] = pos.attacks_from<KING>(pos.square<KING>(WHITE));
ei.attackedBy[BLACK][KING] = pos.attacks_from<KING>(pos.square<KING>(BLACK));
eval_init<WHITE>(pos, ei);
eval_init<BLACK>(pos, ei);
// Pawns blocked or on ranks 2 and 3 will be excluded from the mobility area
Bitboard blockedPawns[] = {
pos.pieces(WHITE, PAWN) & (shift<SOUTH>(pos.pieces()) | Rank2BB | Rank3BB),
pos.pieces(BLACK, PAWN) & (shift<NORTH>(pos.pieces()) | Rank7BB | Rank6BB)
};
// Do not include in mobility area squares protected by enemy pawns, or occupied
// by our blocked pawns or king.
Bitboard mobilityArea[] = {
~(ei.attackedBy[BLACK][PAWN] | blockedPawns[WHITE] | pos.square<KING>(WHITE)),
~(ei.attackedBy[WHITE][PAWN] | blockedPawns[BLACK] | pos.square<KING>(BLACK))
};
// Evaluate all pieces but king and pawns
score += evaluate_pieces<DoTrace>(pos, ei, mobility, mobilityArea);
score += evaluate_pieces<DoTrace>(pos, ei, mobility);
score += mobility[WHITE] - mobility[BLACK];
// Evaluate kings after all other pieces because we need full attack
@ -876,7 +874,7 @@ Value Eval::evaluate(const Position& pos) {
- evaluate_space<BLACK>(pos, ei);
// Evaluate position potential for the winning side
score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score));
score += evaluate_initiative(pos, ei.pe->pawn_asymmetry(), eg_value(score));
// Evaluate scale factor for the winning side
ScaleFactor sf = evaluate_scale_factor(pos, ei, eg_value(score));
@ -892,7 +890,7 @@ Value Eval::evaluate(const Position& pos) {
{
Trace::add(MATERIAL, pos.psq_score());
Trace::add(IMBALANCE, ei.me->imbalance());
Trace::add(PAWN, ei.pi->pawns_score());
Trace::add(PAWN, ei.pe->pawns_score());
Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]);
if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222)
Trace::add(SPACE, evaluate_space<WHITE>(pos, ei)