Expose EvalInfo struct to search

Allow to use EvalInfo struct, populated by
evaluation(), in search.

In particular we allocate Eval::Info on the stack
and pass a pointer to this to evaluate().

Also add to Search::Stack a pointer to Eval::Info,
this allows to reference eval info of previous/next
nodes.

WARNING: Eval::Info is NOT initialized and is populated
by evaluate(), only if the latter is called, and this
does not happen in all the code paths, so care should be
taken when accessing this struct.

No functional change.
This commit is contained in:
Marco Costalba
2013-04-25 12:43:55 +02:00
parent 79bcb2ca54
commit d810441b35
4 changed files with 76 additions and 69 deletions

View File

@@ -20,14 +20,56 @@
#if !defined(EVALUATE_H_INCLUDED)
#define EVALUATE_H_INCLUDED
#include "material.h"
#include "pawns.h"
#include "types.h"
class Position;
namespace Eval {
// Struct Eval::Info contains various information computed and collected
// by the evaluation functions.
struct Info {
// Pointers to material and pawn hash table entries
Material::Entry* mi;
Pawns::Entry* pi;
// attackedBy[color][piece type] is a bitboard representing all squares
// attacked by a given color and piece type, attackedBy[color][ALL_PIECES]
// contains all squares attacked by the given color.
Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
// kingRing[color] is the zone around the king which is considered
// by the king safety evaluation. This consists of the squares directly
// adjacent to the king, and the three (or two, for a king on an edge file)
// squares two ranks in front of the king. For instance, if black's king
// is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8,
// f7, g7, h7, f6, g6 and h6.
Bitboard kingRing[COLOR_NB];
// kingAttackersCount[color] is the number of pieces of the given color
// which attack a square in the kingRing of the enemy king.
int kingAttackersCount[COLOR_NB];
// kingAttackersWeight[color] is the sum of the "weight" of the pieces of the
// given color which attack a square in the kingRing of the enemy king. The
// weights of the individual piece types are given by the variables
// QueenAttackWeight, RookAttackWeight, BishopAttackWeight and
// KnightAttackWeight in evaluate.cpp
int kingAttackersWeight[COLOR_NB];
// kingAdjacentZoneAttacksCount[color] is the number of attacks to squares
// directly adjacent to the king of the given color. Pieces which attack
// more than one square are counted multiple times. For instance, if black's
// king is on g8 and there's a white knight on g5, this knight adds
// 2 to kingAdjacentZoneAttacksCount[BLACK].
int kingAdjacentZoneAttacksCount[COLOR_NB];
};
extern void init();
extern Value evaluate(const Position& pos, Value& margin);
extern Value evaluate(const Position& pos, Value& margin, Info* ei);
extern std::string trace(const Position& pos);
}