/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 Marco Costalba
+ Copyright (C) 2008-2009 Marco Costalba
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <cassert>
#include <cstring>
+#include "bitcount.h"
#include "evaluate.h"
#include "material.h"
#include "pawns.h"
namespace {
- const int Sign[2] = {1, -1};
+ const int Sign[2] = { 1, -1 };
- // Evaluation grain size, must be a power of 2.
+ // Evaluation grain size, must be a power of 2
const int GrainSize = 4;
- // Evaluation weights
- int WeightMobilityMidgame = 0x100;
- int WeightMobilityEndgame = 0x100;
- int WeightPawnStructureMidgame = 0x100;
- int WeightPawnStructureEndgame = 0x100;
- int WeightPassedPawnsMidgame = 0x100;
- int WeightPassedPawnsEndgame = 0x100;
- int WeightKingSafety[2] = { 0x100, 0x100 };
+ // Evaluation weights, initialized from UCI options
+ int WeightMobilityMidgame, WeightMobilityEndgame;
+ int WeightPawnStructureMidgame, WeightPawnStructureEndgame;
+ int WeightPassedPawnsMidgame, WeightPassedPawnsEndgame;
+ int WeightKingSafety[2];
int WeightSpace;
- // Internal evaluation weights. These are applied on top of the evaluation
- // weights read from UCI parameters. The purpose is to be able to change
+ // Internal evaluation weights. These are applied on top of the evaluation
+ // weights read from UCI parameters. The purpose is to be able to change
// the evaluation weights while keeping the default values of the UCI
// parameters at 100, which looks prettier.
//
// Values modified by Joona Kiiski
- const int WeightMobilityMidgameInternal = 0x0FA;
- const int WeightMobilityEndgameInternal = 0x10A;
- const int WeightPawnStructureMidgameInternal = 0x0EC;
- const int WeightPawnStructureEndgameInternal = 0x0CD;
- const int WeightPassedPawnsMidgameInternal = 0x108;
- const int WeightPassedPawnsEndgameInternal = 0x109;
- const int WeightKingSafetyInternal = 0x0F7;
- const int WeightKingOppSafetyInternal = 0x101;
- const int WeightSpaceInternal = 0x02F;
-
+ const int WeightMobilityMidgameInternal = 248;
+ const int WeightMobilityEndgameInternal = 271;
+ const int WeightPawnStructureMidgameInternal = 233;
+ const int WeightPawnStructureEndgameInternal = 201;
+ const int WeightPassedPawnsMidgameInternal = 252;
+ const int WeightPassedPawnsEndgameInternal = 259;
+ const int WeightKingSafetyInternal = 247;
+ const int WeightKingOppSafetyInternal = 259;
+ const int WeightSpaceInternal = 46;
+
+ // Mobility and outposts bonus modified by Joona Kiiski
+ //
// Visually better to define tables constants
typedef Value V;
// of attacked squares not occupied by friendly piecess.
const Value MidgameKnightMobilityBonus[] = {
// 0 1 2 3 4 5 6 7 8
- V(-30), V(-20),V(-10), V(0), V(10), V(20), V(25), V(30), V(30)
+ V(-38), V(-25),V(-12), V(0), V(12), V(25), V(31), V(38), V(38)
};
const Value EndgameKnightMobilityBonus[] = {
// 0 1 2 3 4 5 6 7 8
- V(-30), V(-20),V(-10), V(0), V(10), V(20), V(25), V(30), V(30)
+ V(-33), V(-23),V(-13), V(-3), V(7), V(17), V(22), V(27), V(27)
};
// Bishop mobility bonus in middle game and endgame, indexed by the number
- // of attacked squares not occupied by friendly pieces. X-ray attacks through
+ // of attacked squares not occupied by friendly pieces. X-ray attacks through
// queens are also included.
const Value MidgameBishopMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-30), V(-15), V(0), V(15), V(30), V(45), V(58), V(66),
+ V(-25), V(-11), V(3), V(17), V(31), V(45), V(57), V(65),
// 8 9 10 11 12 13 14 15
- V( 72), V( 76), V(78), V(80), V(81), V(82), V(83), V(83)
+ V( 71), V( 74), V(76), V(78), V(79), V(80), V(81), V(81)
};
const Value EndgameBishopMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-30), V(-15), V(0), V(15), V(30), V(45), V(58), V(66),
+ V(-30), V(-16), V(-2), V(12), V(26), V(40), V(52), V(60),
// 8 9 10 11 12 13 14 15
- V( 72), V( 76), V(78), V(80), V(81), V(82), V(83), V(83)
+ V( 65), V( 69), V(71), V(73), V(74), V(75), V(76), V(76)
};
// Rook mobility bonus in middle game and endgame, indexed by the number
- // of attacked squares not occupied by friendly pieces. X-ray attacks through
+ // of attacked squares not occupied by friendly pieces. X-ray attacks through
// queens and rooks are also included.
const Value MidgameRookMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-18), V(-12), V(-6), V(0), V(6), V(12), V(16), V(21),
+ V(-20), V(-14), V(-8), V(-2), V(4), V(10), V(14), V(19),
// 8 9 10 11 12 13 14 15
- V( 24), V( 27), V(28), V(29), V(30), V(31), V(32), V(33)
+ V( 23), V( 26), V(27), V(28), V(29), V(30), V(31), V(32)
};
const Value EndgameRookMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-30), V(-18), V(-6), V(6), V(18), V(30), V(42), V(54),
+ V(-36), V(-19), V(-3), V(13), V(29), V(46), V(62), V(79),
// 8 9 10 11 12 13 14 15
- V( 66), V( 74), V(78), V(80), V(81), V(82), V(83), V(83)
+ V( 95), V(106),V(111),V(114),V(116),V(117),V(118),V(118)
};
// Queen mobility bonus in middle game and endgame, indexed by the number
// of attacked squares not occupied by friendly pieces.
const Value MidgameQueenMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-10), V(-8), V(-6), V(-4), V(-2), V( 0), V( 2), V( 4),
+ V(-10), V(-8), V(-6), V(-3), V(-1), V( 1), V( 3), V( 5),
// 8 9 10 11 12 13 14 15
- V( 6), V( 8), V(10), V(12), V(13), V(14), V(15), V(16),
+ V( 8), V(10), V(12), V(15), V(16), V(17), V(18), V(20),
// 16 17 18 19 20 21 22 23
- V( 16), V(16), V(16), V(16), V(16), V(16), V(16), V(16),
+ V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20),
// 24 25 26 27 28 29 30 31
- V( 16), V(16), V(16), V(16), V(16), V(16), V(16), V(16)
+ V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20)
};
const Value EndgameQueenMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
- V(-20),V(-15),V(-10), V(-5), V( 0), V( 5), V(10), V(15),
+ V(-18),V(-13), V(-7), V(-2), V( 3), V (8), V(13), V(19),
// 8 9 10 11 12 13 14 15
- V( 19), V(23), V(27), V(29), V(30), V(30), V(30), V(30),
+ V( 23), V(27), V(32), V(34), V(35), V(35), V(35), V(35),
// 16 17 18 19 20 21 22 23
- V( 30), V(30), V(30), V(30), V(30), V(30), V(30), V(30),
+ V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35),
// 24 25 26 27 28 29 30 31
- V( 30), V(30), V(30), V(30), V(30), V(30), V(30), V(30)
+ V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35)
};
// Outpost bonuses for knights and bishops, indexed by square (from white's
// A B C D E F G H
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 1
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2
- V(0), V(0), V(5),V(10),V(10), V(5), V(0), V(0), // 3
- V(0), V(5),V(20),V(30),V(30),V(20), V(5), V(0), // 4
- V(0),V(10),V(30),V(40),V(40),V(30),V(10), V(0), // 5
- V(0), V(5),V(20),V(20),V(20),V(20), V(5), V(0), // 6
+ V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), // 3
+ V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), // 4
+ V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), // 5
+ V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0), // 6
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8
};
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2
V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), // 3
V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), // 4
- V(0),V(10),V(20),V(20),V(20),V(20),V(10), V(0), // 5
+ V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), // 5
V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0), // 6
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8
// Bonus for unstoppable passed pawns
const Value UnstoppablePawnValue = Value(0x500);
- // Rooks and queens on the 7th rank
+ // Rooks and queens on the 7th rank (modified by Joona Kiiski)
const Value MidgameRookOn7thBonus = Value(47);
const Value EndgameRookOn7thBonus = Value(98);
const Value MidgameQueenOn7thBonus = Value(27);
const Value EndgameQueenOn7thBonus = Value(54);
-
- // Rooks on open files
+ // Rooks on open files (modified by Joona Kiiski)
const Value RookOpenFileBonus = Value(43);
const Value RookHalfOpenFileBonus = Value(19);
// Penalty for rooks trapped inside a friendly king which has lost the
- // right to castle:
+ // right to castle.
const Value TrappedRookPenalty = Value(180);
// Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by
- // enemy pawns:
+ // enemy pawns.
const Value TrappedBishopA7H7Penalty = Value(300);
- // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black):
+ // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black)
const Bitboard MaskA7H7[2] = {
((1ULL << SQ_A7) | (1ULL << SQ_H7)),
((1ULL << SQ_A2) | (1ULL << SQ_H2))
};
// Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
- // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
+ // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
// happen in Chess960 games.
const Value TrappedBishopA1H1Penalty = Value(100);
- // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black):
+ // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black)
const Bitboard MaskA1H1[2] = {
((1ULL << SQ_A1) | (1ULL << SQ_H1)),
((1ULL << SQ_A8) | (1ULL << SQ_H8))
};
// The SpaceMask[color] contains area of the board which is consdered by
- // the space evaluation. In the middle game, each side is given a bonus
+ // the space evaluation. In the middle game, each side is given a bonus
// based on how many squares inside this area are safe and available for
// friendly minor pieces.
const Bitboard SpaceMask[2] = {
(1ULL<<SQ_C5) | (1ULL<<SQ_D5) | (1ULL<<SQ_E5) | (1ULL<<SQ_F5)
};
- /// King safety constants and variables. The king safety scores are taken
- /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
+ /// King safety constants and variables. The king safety scores are taken
+ /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
/// the strength of the attack are added up into an integer, which is used
/// as an index to SafetyTable[].
- // Attack weights for each piece type.
+ // Attack weights for each piece type
const int QueenAttackWeight = 5;
const int RookAttackWeight = 3;
const int BishopAttackWeight = 2;
const int KnightAttackWeight = 2;
- // Bonuses for safe checks for each piece type.
- int QueenContactCheckBonus = 3;
- int QueenCheckBonus = 2;
- int RookCheckBonus = 1;
- int BishopCheckBonus = 1;
- int KnightCheckBonus = 1;
- int DiscoveredCheckBonus = 3;
+ // Bonuses for safe checks, initialized from UCI options
+ int QueenContactCheckBonus, DiscoveredCheckBonus;
+ int QueenCheckBonus, RookCheckBonus, BishopCheckBonus, KnightCheckBonus;
// Scan for queen contact mates?
const bool QueenContactMates = true;
- // Bonus for having a mate threat.
- int MateThreatBonus = 3;
+ // Bonus for having a mate threat, initialized from UCI options
+ int MateThreatBonus;
// InitKingDanger[] contains bonuses based on the position of the defending
// king.
15, 15, 15, 15, 15, 15, 15, 15
};
- // SafetyTable[] contains the actual king safety scores. It is initialized
+ // SafetyTable[] contains the actual king safety scores. It is initialized
// in init_safety().
Value SafetyTable[100];
// Pawn and material hash tables, indexed by the current thread id
- PawnInfoTable *PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
- MaterialInfoTable *MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ PawnInfoTable* PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ MaterialInfoTable* MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
// Sizes of pawn and material hash tables
const int PawnTableSize = 16384;
const int MaterialTableSize = 1024;
- // Array which gives the number of nonzero bits in an 8-bit integer:
+ // Array which gives the number of nonzero bits in an 8-bit integer
uint8_t BitCount8Bit[256];
// Function prototypes
- template<PieceType Piece>
+ template<bool HasPopCnt>
+ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID);
+
+ template<PieceType Piece, bool HasPopCnt>
void evaluate_pieces(const Position& p, Color us, EvalInfo& ei);
- template<>
- void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo &ei);
+ template<bool HasPopCnt>
+ void evaluate_king(const Position& p, Color us, EvalInfo &ei);
void evaluate_passed_pawns(const Position &pos, EvalInfo &ei);
void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
EvalInfo &ei);
void evaluate_trapped_bishop_a1h1(const Position &pos, Square s, Color us,
EvalInfo &ei);
-
+ template<bool HasPopCnt>
void evaluate_space(const Position &p, Color us, EvalInfo &ei);
inline Value apply_weight(Value v, int w);
-
- int count_1s_8bit(Bitboard b);
+ Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]);
int compute_weight(int uciWeight, int internalWeight);
int weight_option(const std::string& opt, int weight);
//// Functions
////
-/// evaluate() is the main evaluation function. It always computes two
+/// evaluate() is the main evaluation function. It always computes two
/// values, an endgame score and a middle game score, and interpolates
/// between them based on the remaining material.
+Value evaluate(const Position& pos, EvalInfo& ei, int threadID) {
-Value evaluate(const Position &pos, EvalInfo &ei, int threadID) {
+ return CpuHasPOPCNT ? do_evaluate<true>(pos, ei, threadID)
+ : do_evaluate<false>(pos, ei, threadID);
+}
+
+namespace {
+
+template<bool HasPopCnt>
+Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) {
assert(pos.is_ok());
assert(threadID >= 0 && threadID < THREAD_MAX);
// Initialize pawn attack bitboards for both sides
ei.attackedBy[WHITE][PAWN] = ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB);
ei.attackedBy[BLACK][PAWN] = ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB);
- ei.kingAttackersCount[WHITE] = count_1s_max_15(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
- ei.kingAttackersCount[BLACK] = count_1s_max_15(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
+ ei.kingAttackersCount[WHITE] = count_1s_max_15<HasPopCnt>(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
+ ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
// Evaluate pieces
for (Color c = WHITE; c <= BLACK; c++)
{
- evaluate_pieces<KNIGHT>(pos, c, ei);
- evaluate_pieces<BISHOP>(pos, c, ei);
- evaluate_pieces<ROOK>(pos, c, ei);
- evaluate_pieces<QUEEN>(pos, c, ei);
+ evaluate_pieces<KNIGHT, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<BISHOP, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<ROOK, HasPopCnt>(pos, c, ei);
+ evaluate_pieces<QUEEN, HasPopCnt>(pos, c, ei);
// Sum up all attacked squares
ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
| ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING];
}
- // Kings. Kings are evaluated after all other pieces for both sides,
+ // Kings. Kings are evaluated after all other pieces for both sides,
// because we need complete attack information for all pieces when computing
// the king safety evaluation.
for (Color c = WHITE; c <= BLACK; c++)
- evaluate_pieces<KING>(pos, c, ei);
+ evaluate_king<HasPopCnt>(pos, c, ei);
// Evaluate passed pawns. We evaluate passed pawns for both sides at once,
// because we need to know which side promotes first in positions where
// Evaluate space for both sides
if (ei.mi->space_weight() > 0)
{
- evaluate_space(pos, WHITE, ei);
- evaluate_space(pos, BLACK, ei);
+ evaluate_space<HasPopCnt>(pos, WHITE, ei);
+ evaluate_space<HasPopCnt>(pos, BLACK, ei);
}
}
return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v);
}
+} // namespace
/// quick_evaluate() does a very approximate evaluation of the current position.
/// It currently considers only material and piece square table scores. Perhaps
}
for (Bitboard b = 0ULL; b < 256ULL; b++)
- BitCount8Bit[b] = count_1s(b);
+ {
+ assert(count_1s(b) == int(uint8_t(count_1s(b))));
+ BitCount8Bit[b] = (uint8_t)count_1s(b);
+ }
}
{
delete PawnTable[i];
delete MaterialTable[i];
+ PawnTable[i] = NULL;
+ MaterialTable[i] = NULL;
}
}
}
-/// scale_by_game_phase() interpolates between a middle game and an endgame
-/// score, based on game phase. It also scales the return value by a
-/// ScaleFactor array.
-
-Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) {
-
- assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
- assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
- assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
-
- ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
-
- Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
- return Value(int(result) & ~(GrainSize - 1));
-}
-
namespace {
- // evaluate_common() computes terms common to all pieces attack
+ // evaluate_mobility() computes mobility and attacks for every piece
- template<PieceType Piece>
- int evaluate_common(const Position& p, const Bitboard& b, Color us, EvalInfo& ei, Square s = SQ_NONE) {
+ template<PieceType Piece, bool HasPopCnt>
+ int evaluate_mobility(const Position& p, const Bitboard& b, Color us, Color them, EvalInfo& ei) {
static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight };
static const Value* MgBonus[] = { 0, 0, MidgameKnightMobilityBonus, MidgameBishopMobilityBonus, MidgameRookMobilityBonus, MidgameQueenMobilityBonus };
static const Value* EgBonus[] = { 0, 0, EndgameKnightMobilityBonus, EndgameBishopMobilityBonus, EndgameRookMobilityBonus, EndgameQueenMobilityBonus };
- static const Value* OutpostBonus[] = { 0, 0, KnightOutpostBonus, BishopOutpostBonus, 0, 0 };
-
- Color them = opposite_color(us);
// Update attack info
ei.attackedBy[us][Piece] |= b;
- // King attack
+ // King attacks
if (b & ei.kingZone[us])
{
ei.kingAttackersCount[us]++;
ei.kingAttackersWeight[us] += AttackWeight[Piece];
Bitboard bb = (b & ei.attackedBy[them][KING]);
if (bb)
- ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15(bb);
+ ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15<HasPopCnt>(bb);
}
// Remove squares protected by enemy pawns
Bitboard bb = (b & ~ei.attackedBy[them][PAWN]);
// Mobility
- int mob = (Piece != QUEEN ? count_1s_max_15(bb & ~p.pieces_of_color(us))
- : count_1s(bb & ~p.pieces_of_color(us)));
+ int mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(bb & ~p.pieces_of_color(us))
+ : count_1s<HasPopCnt>(bb & ~p.pieces_of_color(us)));
ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
ei.egMobility += Sign[us] * EgBonus[Piece][mob];
+ return mob;
+ }
- // Bishop and Knight outposts
- if ( (Piece != BISHOP && Piece != KNIGHT) // compile time condition
- || !p.square_is_weak(s, them))
- return mob;
+
+ // evaluate_outposts() evaluates bishop and knight outposts squares
+
+ template<PieceType Piece>
+ void evaluate_outposts(const Position& p, Color us, Color them, EvalInfo& ei, Square s) {
// Initial bonus based on square
- Value v, bonus;
- v = bonus = OutpostBonus[Piece][relative_square(us, s)];
+ Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(us, s)]
+ : KnightOutpostBonus[relative_square(us, s)]);
// Increase bonus if supported by pawn, especially if the opponent has
// no minor piece which can exchange the outpost piece
- if (v && (p.pawn_attacks(them, s) & p.pawns(us)))
+ if (bonus && (p.pawn_attacks(them, s) & p.pawns(us)))
{
- bonus += v / 2;
- if ( p.piece_count(them, KNIGHT) == 0
+ if ( p.knights(them) == EmptyBoardBB
&& (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
- bonus += v;
+ bonus += bonus + bonus / 2;
+ else
+ bonus += bonus / 2;
}
ei.mgValue += Sign[us] * bonus;
ei.egValue += Sign[us] * bonus;
- return mob;
}
// evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given
// color.
- template<PieceType Piece>
+ template<PieceType Piece, bool HasPopCnt>
void evaluate_pieces(const Position& pos, Color us, EvalInfo& ei) {
Bitboard b;
Square s, ksq;
- Color them;
int mob;
File f;
+ Color them = opposite_color(us);
for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++)
{
b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.queens(us));
else if (Piece == ROOK)
b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us));
+ else
+ assert(false);
- // Attacks, mobility and outposts
- mob = evaluate_common<Piece>(pos, b, us, ei, s);
+ // Attacks and mobility
+ mob = evaluate_mobility<Piece, HasPopCnt>(pos, b, us, them, ei);
+
+ // Bishop and knight outposts squares
+ if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, them))
+ evaluate_outposts<Piece>(pos, us, them, ei, s);
// Special patterns: trapped bishops on a7/h7/a2/h2
// and trapped bishops on a1/h1/a8/h8 in Chess960.
evaluate_trapped_bishop_a1h1(pos, s, us, ei);
}
- if (Piece != ROOK && Piece != QUEEN)
- continue;
-
- // Queen or rook on 7th rank
- them = opposite_color(us);
-
- if ( relative_rank(us, s) == RANK_7
- && relative_rank(us, pos.king_square(them)) == RANK_8)
+ if (Piece == ROOK || Piece == QUEEN)
{
- ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
- ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ // Queen or rook on 7th rank
+ if ( relative_rank(us, s) == RANK_7
+ && relative_rank(us, pos.king_square(them)) == RANK_8)
+ {
+ ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
+ ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ }
}
// Special extra evaluation for rooks
- if (Piece != ROOK)
- continue;
-
- // Open and half-open files
- f = square_file(s);
- if (ei.pi->file_is_half_open(us, f))
+ if (Piece == ROOK)
{
- if (ei.pi->file_is_half_open(them, f))
+ // Open and half-open files
+ f = square_file(s);
+ if (ei.pi->file_is_half_open(us, f))
{
- ei.mgValue += Sign[us] * RookOpenFileBonus;
- ei.egValue += Sign[us] * RookOpenFileBonus;
- }
- else
- {
- ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
- ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ if (ei.pi->file_is_half_open(them, f))
+ {
+ ei.mgValue += Sign[us] * RookOpenFileBonus;
+ ei.egValue += Sign[us] * RookOpenFileBonus;
+ }
+ else
+ {
+ ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
+ ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ }
}
- }
- // Penalize rooks which are trapped inside a king. Penalize more if
- // king has lost right to castle.
- if (mob > 6 || ei.pi->file_is_half_open(us, f))
- continue;
+ // Penalize rooks which are trapped inside a king. Penalize more if
+ // king has lost right to castle.
+ if (mob > 6 || ei.pi->file_is_half_open(us, f))
+ continue;
- ksq = pos.king_square(us);
+ ksq = pos.king_square(us);
- if ( square_file(ksq) >= FILE_E
- && square_file(s) > square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
- }
- else if ( square_file(ksq) <= FILE_D
- && square_file(s) < square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
+ if ( square_file(ksq) >= FILE_E
+ && square_file(s) > square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
+ else if ( square_file(ksq) <= FILE_D
+ && square_file(s) < square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
}
}
}
return b >> (num << 3);
}
- // evaluate_pieces<KING>() assigns bonuses and penalties to a king of a given
- // color.
+ // evaluate_king<>() assigns bonuses and penalties to a king of a given color.
- template<>
- void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo& ei) {
+ template<bool HasPopCnt>
+ void evaluate_king(const Position& p, Color us, EvalInfo& ei) {
int shelter = 0, sign = Sign[us];
Square s = p.king_square(us);
// King shelter
if (relative_rank(us, s) <= RANK_4)
{
- Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
- Rank r = square_rank(s);
- for (int i = 1; i < 4; i++)
- shelter += count_1s_8bit(shiftRowsDown(pawns, r+i*sign)) * (128>>i);
-
+ // Shelter cache lookup
+ shelter = ei.pi->kingShelter(us, s);
+ if (shelter == -1)
+ {
+ shelter = 0;
+ Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
+ Rank r = square_rank(s);
+ for (int i = 1; i < 4; i++)
+ shelter += BitCount8Bit[shiftRowsDown(pawns, r+i*sign) & 0xFF] * (128 >> i);
+
+ // Cache shelter value in pawn info
+ ei.pi->setKingShelter(us, s, shelter);
+ }
ei.mgValue += sign * Value(shelter);
}
- // King safety. This is quite complicated, and is almost certainly far
+ // King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
Color them = opposite_color(us);
// quality of the pawn shelter.
int attackUnits =
Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
- + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15(undefended)) * 3
+ + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15<HasPopCnt>(undefended)) * 3
+ InitKingDanger[relative_square(us, s)] - (shelter >> 5);
// Analyse safe queen contact checks
{
// The bitboard b now contains the squares available for safe queen
// contact checks.
- int count = count_1s_max_15(b);
+ int count = count_1s_max_15<HasPopCnt>(b);
attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1);
// Is there a mate threat?
if ( bit_is_set(p.piece_attacks<QUEEN>(from), to)
&& !bit_is_set(p.pinned_pieces(them), from)
&& !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))
- && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us)))
+ && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & p.bishops_and_queens(us)))
ei.mateThreat[them] = make_move(from, to);
}
// Queen checks
b2 = b & ei.attacked_by(them, QUEEN);
if( b2)
- attackUnits += QueenCheckBonus * count_1s_max_15(b2);
+ attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b2);
// Rook checks
b2 = b & ei.attacked_by(them, ROOK);
if (b2)
- attackUnits += RookCheckBonus * count_1s_max_15(b2);
+ attackUnits += RookCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
if (QueenCheckBonus > 0 || BishopCheckBonus > 0)
{
// Queen checks
b2 = b & ei.attacked_by(them, QUEEN);
if (b2)
- attackUnits += QueenCheckBonus * count_1s_max_15(b2);
+ attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b2);
// Bishop checks
b2 = b & ei.attacked_by(them, BISHOP);
if (b2)
- attackUnits += BishopCheckBonus * count_1s_max_15(b2);
+ attackUnits += BishopCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
if (KnightCheckBonus > 0)
{
// Knight checks
b2 = b & ei.attacked_by(them, KNIGHT);
if (b2)
- attackUnits += KnightCheckBonus * count_1s_max_15(b2);
+ attackUnits += KnightCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
// Analyse discovered checks (only for non-pawns right now, consider
{
b = p.discovered_check_candidates(them) & ~p.pawns();
if (b)
- attackUnits += DiscoveredCheckBonus * count_1s_max_15(b) * (sente? 2 : 1);
+ attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente? 2 : 1);
}
// Has a mate threat been found? We don't do anything here if the
&& (squares_behind(us, s) & pos.rooks_and_queens(them)))
b3 = b2;
- if ((b2 & pos.pieces_of_color(them)) == EmptyBoardBB)
- {
- // There are no enemy pieces in the pawn's path! Are any of the
- // squares in the pawn's path attacked by the enemy?
- if (b3 == EmptyBoardBB)
- // No enemy attacks, huge bonus!
- ebonus += Value(tr * (b2 == b4 ? 17 : 15));
- else
- // OK, there are enemy attacks. Are those squares which are
- // attacked by the enemy also attacked by us? If yes, big bonus
- // (but smaller than when there are no enemy attacks), if no,
- // somewhat smaller bonus.
- ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8));
- }
+ // Squares attacked or occupied by enemy pieces
+ b3 |= (b2 & pos.pieces_of_color(them));
+
+ // There are no enemy pawns in the pawn's path
+ assert((b2 & pos.pieces_of_color_and_type(them, PAWN)) == EmptyBoardBB);
+
+ // Are any of the squares in the pawn's path attacked or occupied by the enemy?
+ if (b3 == EmptyBoardBB)
+ // No enemy attacks or pieces, huge bonus!
+ ebonus += Value(tr * (b2 == b4 ? 17 : 15));
else
- {
- // There are some enemy pieces in the pawn's path. While this is
- // sad, we still assign a moderate bonus if all squares in the path
- // which are either occupied by or attacked by enemy pieces are
- // also attacked by us.
- if (((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB)
- ebonus += Value(tr * 6);
- }
+ // OK, there are enemy attacks or pieces (but not pawns). Are those
+ // squares which are attacked by the enemy also attacked by us?
+ // If yes, big bonus (but smaller than when there are no enemy attacks),
+ // if no, somewhat smaller bonus.
+ ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8));
+
// At last, add a small bonus when there are no *friendly* pieces
// in the pawn's path.
if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB)
}
}
}
- // Rook pawns are a special case: They are sometimes worse, and
+ // Rook pawns are a special case: They are sometimes worse, and
// sometimes better than other passed pawns. It is difficult to find
// good rules for determining whether they are good or bad. For now,
// we try the following: Increase the value for rook pawns if the
// value if the other side has a rook or queen.
if (square_file(s) == FILE_A || square_file(s) == FILE_H)
{
- if( pos.non_pawn_material(them) <= KnightValueMidgame
- && pos.piece_count(them, KNIGHT) <= 1)
+ if ( pos.non_pawn_material(them) <= KnightValueMidgame
+ && pos.piece_count(them, KNIGHT) <= 1)
ebonus += ebonus / 4;
- else if(pos.rooks_and_queens(them))
+ else if (pos.rooks_and_queens(them))
ebonus -= ebonus / 4;
}
// Does either side have an unstoppable passed pawn?
if (hasUnstoppable[WHITE] && !hasUnstoppable[BLACK])
- ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]);
+ ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]);
else if (hasUnstoppable[BLACK] && !hasUnstoppable[WHITE])
- ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]);
+ ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]);
else if (hasUnstoppable[BLACK] && hasUnstoppable[WHITE])
{
// Both sides have unstoppable pawns! Try to find out who queens
// squares one, two or three squares behind a friendly pawn are counted
// twice. Finally, the space bonus is scaled by a weight taken from the
// material hash table.
-
+ template<bool HasPopCnt>
void evaluate_space(const Position &pos, Color us, EvalInfo &ei) {
Color them = opposite_color(us);
behindFriendlyPawns |= (behindFriendlyPawns << 16);
}
- int space = count_1s_max_15(safeSquares)
- + count_1s_max_15(behindFriendlyPawns & safeSquares);
+ int space = count_1s_max_15<HasPopCnt>(safeSquares)
+ + count_1s_max_15<HasPopCnt>(behindFriendlyPawns & safeSquares);
ei.mgValue += Sign[us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace);
}
}
- // count_1s_8bit() counts the number of nonzero bits in the 8 least
- // significant bits of a Bitboard. This function is used by the king
- // shield evaluation.
+ // scale_by_game_phase() interpolates between a middle game and an endgame
+ // score, based on game phase. It also scales the return value by a
+ // ScaleFactor array.
+
+ Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) {
+
+ assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
+ assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
+ assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
+
+ ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
- int count_1s_8bit(Bitboard b) {
- return int(BitCount8Bit[b & 0xFF]);
+ Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
+ return Value(int(result) & ~(GrainSize - 1));
}