#include <cassert>
#include "book.h"
-#include "mersenne.h"
#include "movegen.h"
using namespace std;
-////
-//// Global variables
-////
-
-Book OpeningBook;
-
-
////
//// Local definitions
////
namespace {
- /// Book entry size in bytes
+ // Book entry size in bytes
const int EntrySize = 16;
-
- /// Random numbers from PolyGlot, used to compute book hash keys
-
+ // Random numbers from PolyGlot, used to compute book hash keys
const uint64_t Random64[781] = {
0x9D39247E33776D41ULL, 0x2AF7398005AAA5C7ULL, 0x44DB015024623547ULL,
0x9C15F73E62A76AE2ULL, 0x75834465489C0C89ULL, 0x3290AC3A203001BFULL,
0xF8D626AAAF278509ULL
};
+ // Indices to the Random64[] array
+ const int PieceIdx = 0;
+ const int CastleIdx = 768;
+ const int EnPassantIdx = 772;
+ const int TurnIdx = 780;
- /// Indices to the Random64[] array
-
- const int RandomPiece = 0;
- const int RandomCastle = 768;
- const int RandomEnPassant = 772;
- const int RandomTurn = 780;
-
-
- /// Prototypes
-
+ // Local functions
uint64_t book_key(const Position& pos);
uint64_t book_piece_key(Piece p, Square s);
uint64_t book_castle_key(const Position& pos);
//// Functions
////
+// C'tor. Make random number generation less deterministic, for book moves
+Book::Book() {
+
+ for (int i = abs(get_system_time() % 10000); i > 0; i--)
+ RKiss.rand<unsigned>();
+}
+
/// Destructor. Be sure file is closed before we leave.
}
+/// Book::close() closes the file only if it is open, otherwise
+/// we can end up in a little mess due to how std::ifstream works.
+
+void Book::close() {
+
+ if (is_open())
+ ifstream::close();
+}
+
+
/// Book::open() opens a book file with a given file name
void Book::open(const string& fName) {
fileName = fName;
ifstream::open(fileName.c_str(), ifstream::in | ifstream::binary);
- if (!is_open())
- return;
-
- // Get the book size in number of entries
- seekg(0, ios::end);
- bookSize = long(tellg()) / EntrySize;
- seekg(0, ios::beg);
- if (!good())
+ if (is_open())
{
- cerr << "Failed to open book file " << fileName << endl;
- Application::exit_with_failure();
- }
-}
-
-
-/// Book::close() closes the file only if it is open, otherwise
-/// we can end up in a little mess due to how std::ifstream works.
+ // Get the book size in number of entries
+ seekg(0, ios::end);
+ bookSize = long(tellg()) / EntrySize;
+ seekg(0, ios::beg);
-void Book::close() {
-
- if (is_open())
- ifstream::close();
+ if (good())
+ return;
+ }
+ cerr << "Failed to open book file " << fileName << endl;
+ exit(EXIT_FAILURE);
}
BookEntry entry;
int bookMove = MOVE_NONE;
- int scoresSum = 0, bestScore = 0;
+ unsigned scoresSum = 0, bestScore = 0;
uint64_t key = book_key(pos);
// Choose a book move among the possible moves for the given position
if (entry.key != key)
break;
- int score = entry.count;
-
- assert(score > 0);
+ unsigned score = entry.count;
// If findBestMove is true choose highest rated book move
if (findBestMove)
// high score it has more probability to be choosen then a one with
// lower score. Note that first entry is always chosen.
scoresSum += score;
- if (int(genrand_int32() % scoresSum) < score)
+ if (RKiss.rand<unsigned>() % scoresSum < score)
bookMove = entry.move;
}
if (!bookMove)
return MOVE_NONE;
+ // Verify the book move is legal
MoveStack mlist[MOVES_MAX];
MoveStack* last = generate_moves(pos, mlist);
for (MoveStack* cur = mlist; cur != last; cur++)
assert(mid >= left && mid < right);
read_entry(entry, mid);
+
if (key <= entry.key)
right = mid;
else
assert(left == right);
read_entry(entry, left);
- return (entry.key == key)? left : bookSize;
+ return entry.key == key ? left : bookSize;
}
assert(is_open());
seekg(idx * EntrySize, ios_base::beg);
+
*this >> entry;
+
if (!good())
{
cerr << "Failed to read book entry at index " << idx << endl;
- Application::exit_with_failure();
+ exit(EXIT_FAILURE);
}
}
uint64_t Book::read_integer(int size) {
char buf[8];
+ uint64_t n = 0;
+
read(buf, size);
// Numbers are stored on disk as a binary byte stream
- uint64_t n = 0;
for (int i = 0; i < size; i++)
n = (n << 8) + (unsigned char)buf[i];
uint64_t book_key(const Position& pos) {
uint64_t result = 0;
+ Bitboard b = pos.occupied_squares();
- for (Color c = WHITE; c <= BLACK; c++)
+ while (b)
{
- Bitboard b = pos.pieces_of_color(c);
-
- while (b)
- {
- Square s = pop_1st_bit(&b);
- Piece p = pos.piece_on(s);
-
- assert(piece_is_ok(p));
- assert(color_of_piece(p) == c);
-
- result ^= book_piece_key(p, s);
- }
+ Square s = pop_1st_bit(&b);
+ result ^= book_piece_key(pos.piece_on(s), s);
}
+
result ^= book_castle_key(pos);
result ^= book_ep_key(pos);
result ^= book_color_key(pos);
uint64_t book_piece_key(Piece p, Square s) {
- /// Convert pieces to the range 0..11
+ // Convert pieces to the range 0..11
static const int PieceTo12[] = { 0, 0, 2, 4, 6, 8, 10, 0, 0, 1, 3, 5, 7, 9, 11 };
- return Random64[RandomPiece + (PieceTo12[int(p)]^1) * 64 + int(s)];
+ return Random64[PieceIdx + (PieceTo12[int(p)]^1) * 64 + int(s)];
}
uint64_t result = 0;
if (pos.can_castle_kingside(WHITE))
- result ^= Random64[RandomCastle+0];
+ result ^= Random64[CastleIdx + 0];
if (pos.can_castle_queenside(WHITE))
- result ^= Random64[RandomCastle+1];
+ result ^= Random64[CastleIdx + 1];
if (pos.can_castle_kingside(BLACK))
- result ^= Random64[RandomCastle+2];
+ result ^= Random64[CastleIdx + 2];
if (pos.can_castle_queenside(BLACK))
- result ^= Random64[RandomCastle+3];
+ result ^= Random64[CastleIdx + 3];
return result;
}
uint64_t book_ep_key(const Position& pos) {
- return pos.ep_square() == SQ_NONE ? 0 : Random64[RandomEnPassant + square_file(pos.ep_square())];
+
+ return pos.ep_square() == SQ_NONE ? 0 : Random64[EnPassantIdx + square_file(pos.ep_square())];
}
uint64_t book_color_key(const Position& pos) {
- return pos.side_to_move() == WHITE ? Random64[RandomTurn] : 0;
+
+ return pos.side_to_move() == WHITE ? Random64[TurnIdx] : 0;
}
}
projects / stockfish / blobdiff