#include "position.h"
#include "psqtab.h"
#include "san.h"
+#include "tt.h"
#include "ucioption.h"
using std::string;
}
+/// Position::setTranspositionTable() is used by search functions to pass
+/// the pointer to the used TT so that do_move() will prefetch TT access.
+
+void Position::setTranspositionTable(TranspositionTable* tt) {
+ TT = tt;
+}
+
+
/// Position::from_fen() initializes the position object with the given FEN
/// string. This function is not very robust - make sure that input FENs are
/// correct (this is assumed to be the responsibility of the GUI).
if (st->capture)
do_capture_move(st->capture, them, to);
- // Move the piece
- Bitboard move_bb = make_move_bb(from, to);
- do_move_bb(&(byColorBB[us]), move_bb);
- do_move_bb(&(byTypeBB[pt]), move_bb);
- do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares
-
- board[to] = board[from];
- board[from] = EMPTY;
-
// Update hash key
st->key ^= zobrist[us][pt][from] ^ zobrist[us][pt][to];
-
- // Update incremental scores
- st->mgValue += pst_delta<MidGame>(piece, from, to);
- st->egValue += pst_delta<EndGame>(piece, from, to);
-
- // If the moving piece was a king, update the king square
- if (pt == KING)
- kingSquare[us] = to;
+ st->key ^= zobSideToMove;
// Reset en passant square
if (st->epSquare != SQ_NONE)
st->epSquare = SQ_NONE;
}
+ // Update castle rights, try to shortcut a common case
+ if ((castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES)
+ {
+ st->key ^= zobCastle[st->castleRights];
+ st->castleRights &= castleRightsMask[from];
+ st->castleRights &= castleRightsMask[to];
+ st->key ^= zobCastle[st->castleRights];
+ }
+
+ bool checkEpSquare = (pt == PAWN && abs(int(to) - int(from)) == 16);
+
+ // Prefetch TT access as soon as we know key is updated
+ if (!checkEpSquare && TT)
+ TT->prefetch(st->key);
+
+ // Move the piece
+ Bitboard move_bb = make_move_bb(from, to);
+ do_move_bb(&(byColorBB[us]), move_bb);
+ do_move_bb(&(byTypeBB[pt]), move_bb);
+ do_move_bb(&(byTypeBB[0]), move_bb); // HACK: byTypeBB[0] == occupied squares
+
+ board[to] = board[from];
+ board[from] = EMPTY;
+
// If the moving piece was a pawn do some special extra work
if (pt == PAWN)
{
st->pawnKey ^= zobrist[us][PAWN][from] ^ zobrist[us][PAWN][to];
// Set en passant square, only if moved pawn can be captured
- if (abs(int(to) - int(from)) == 16)
+ if (checkEpSquare)
{
if ( (us == WHITE && (pawn_attacks(WHITE, from + DELTA_N) & pawns(BLACK)))
|| (us == BLACK && (pawn_attacks(BLACK, from + DELTA_S) & pawns(WHITE))))
}
}
+ // Prefetch only here in the few cases we needed zobEp[] to update the key
+ if (checkEpSquare && TT)
+ TT->prefetch(st->key);
+
+ // Update incremental scores
+ st->mgValue += pst_delta<MidGame>(piece, from, to);
+ st->egValue += pst_delta<EndGame>(piece, from, to);
+
+ // If the moving piece was a king, update the king square
+ if (pt == KING)
+ kingSquare[us] = to;
+
// Update piece lists
pieceList[us][pt][index[from]] = to;
index[to] = index[from];
- // Update castle rights, try to shortcut a common case
- if ((castleRightsMask[from] & castleRightsMask[to]) != ALL_CASTLES)
- {
- st->key ^= zobCastle[st->castleRights];
- st->castleRights &= castleRightsMask[from];
- st->castleRights &= castleRightsMask[to];
- st->key ^= zobCastle[st->castleRights];
- }
-
// Update checkers bitboard, piece must be already moved
st->checkersBB = EmptyBoardBB;
Square ksq = king_square(them);
}
// Finish
- st->key ^= zobSideToMove;
sideToMove = opposite_color(sideToMove);
gamePly++;
// Update checkers BB
st->checkersBB = attacks_to(king_square(them), us);
+
+ st->key ^= zobSideToMove;
}
// Update checkers BB
st->checkersBB = attacks_to(king_square(them), us);
+
+ st->key ^= zobSideToMove;
}
// Update checkers BB
st->checkersBB = attacks_to(king_square(them), us);
+
+ st->key ^= zobSideToMove;
}
history[gamePly] = st->key;
// Update the necessary information
- sideToMove = opposite_color(sideToMove);
if (st->epSquare != SQ_NONE)
st->key ^= zobEp[st->epSquare];
+ st->key ^= zobSideToMove;
+ TT->prefetch(st->key);
+ sideToMove = opposite_color(sideToMove);
st->epSquare = SQ_NONE;
st->rule50++;
gamePly++;
- st->key ^= zobSideToMove;
st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame;
st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame;
initialKFile = FILE_E;
initialKRFile = FILE_H;
initialQRFile = FILE_A;
+ TT = NULL;
}
// Initialize
TT.new_search();
+ p.setTranspositionTable(&TT);
H.clear();
for (int i = 0; i < 3; i++)
{
// Make and search the move
StateInfo st;
pos.do_move(move, st, dcCandidates);
- TT.prefetch(pos.get_key());
if (moveCount == 1) // The first move in list is the PV
value = -search_pv(pos, ss, -beta, -alpha, newDepth, ply+1, threadID);
StateInfo st;
pos.do_null_move(st);
- TT.prefetch(pos.get_key());
-
int R = (depth >= 5 * OnePly ? 4 : 3); // Null move dynamic reduction
Value nullValue = -search(pos, ss, -(beta-1), depth-R*OnePly, ply+1, false, threadID);
// Make and search the move
StateInfo st;
pos.do_move(move, st, dcCandidates);
- TT.prefetch(pos.get_key());
// Try to reduce non-pv search depth by one ply if move seems not problematic,
// if the move fails high will be re-searched at full depth.
// Make and search the move.
StateInfo st;
pos.do_move(move, st, dcCandidates);
- TT.prefetch(pos.get_key());
Value value = -qsearch(pos, ss, -beta, -alpha, depth-OnePly, ply+1, threadID);
pos.undo_move(move);
}
+/// TranspositionTable::first_entry returns a pointer to the first
+/// entry of a cluster given a position. The low 32 bits of the key
+/// are used to get the index in the table.
+
+inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
+
+ return entries + ((uint32_t(posKey) & (size - 1)) * ClusterSize);
+}
+
+
/// TranspositionTable::store writes a new entry containing a position,
/// a value, a value type, a search depth, and a best move to the
/// transposition table. Transposition table is organized in clusters of
TTEntry* TranspositionTable::retrieve(const Key posKey) const {
uint32_t posKey32 = posKey >> 32;
- TTEntry *tte = first_entry(posKey);
+ TTEntry* tte = first_entry(posKey);
for (int i = 0; i < ClusterSize; i++, tte++)
if (tte->key() == posKey32)
return NULL;
}
+
/// TranspositionTable::prefetch looks up the current position in the
/// transposition table and load it in L1/L2 cache. This is a non
/// blocking function and do not stalls the CPU waiting for data
_mm_prefetch((char*)first_entry(posKey), _MM_HINT_T0);
}
-/// TranspositionTable::first_entry returns a pointer to the first
-/// entry of a cluster given a position. The low 32 bits of the key
-/// are used to get the index in the table.
-
-inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
-
- return entries + ((uint32_t(posKey) & (size - 1)) * ClusterSize);
-}
/// TranspositionTable::new_search() is called at the beginning of every new
/// search. It increments the "generation" variable, which is used to