/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (c) 2013 Ronald de Man
/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (c) 2013 Ronald de Man
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
constexpr int TBPIECES = 7; // Max number of supported pieces
enum { BigEndian, LittleEndian };
constexpr int TBPIECES = 7; // Max number of supported pieces
enum { BigEndian, LittleEndian };
// Each table has a set of flags: all of them refer to DTZ tables, the last one to WDL tables
enum TBFlag { STM = 1, Mapped = 2, WinPlies = 4, LossPlies = 8, Wide = 16, SingleValue = 128 };
inline WDLScore operator-(WDLScore d) { return WDLScore(-int(d)); }
// Each table has a set of flags: all of them refer to DTZ tables, the last one to WDL tables
enum TBFlag { STM = 1, Mapped = 2, WinPlies = 4, LossPlies = 8, Wide = 16, SingleValue = 128 };
inline WDLScore operator-(WDLScore d) { return WDLScore(-int(d)); }
inline Square operator^(Square s, int i) { return Square(int(s) ^ i); }
const std::string PieceToChar = " PNBRQK pnbrqk";
inline Square operator^(Square s, int i) { return Square(int(s) ^ i); }
const std::string PieceToChar = " PNBRQK pnbrqk";
- typedef std::tuple<Key, TBTable<WDL>*, TBTable<DTZ>*> Entry;
+ struct Entry
+ {
+ Key key;
+ TBTable<WDL>* wdl;
+ TBTable<DTZ>* dtz;
+
+ template <TBType Type>
+ TBTable<Type>* get() const {
+ return (TBTable<Type>*)(Type == WDL ? (void*)wdl : (void*)dtz);
+ }
+ };
+ static_assert(std::is_trivially_copyable<Entry>::value, "");
static constexpr int Size = 1 << 12; // 4K table, indexed by key's 12 lsb
static constexpr int Overflow = 1; // Number of elements allowed to map to the last bucket
static constexpr int Size = 1 << 12; // 4K table, indexed by key's 12 lsb
static constexpr int Overflow = 1; // Number of elements allowed to map to the last bucket
void insert(Key key, TBTable<WDL>* wdl, TBTable<DTZ>* dtz) {
uint32_t homeBucket = (uint32_t)key & (Size - 1);
void insert(Key key, TBTable<WDL>* wdl, TBTable<DTZ>* dtz) {
uint32_t homeBucket = (uint32_t)key & (Size - 1);
// Ensure last element is empty to avoid overflow when looking up
for (uint32_t bucket = homeBucket; bucket < Size + Overflow - 1; ++bucket) {
// Ensure last element is empty to avoid overflow when looking up
for (uint32_t bucket = homeBucket; bucket < Size + Overflow - 1; ++bucket) {
- Key otherKey = std::get<KEY>(hashTable[bucket]);
- if (otherKey == key || !std::get<WDL>(hashTable[bucket])) {
+ Key otherKey = hashTable[bucket].key;
+ if (otherKey == key || !hashTable[bucket].get<WDL>()) {
// insert here and search for a new spot for the other element instead.
uint32_t otherHomeBucket = (uint32_t)otherKey & (Size - 1);
if (otherHomeBucket > homeBucket) {
// insert here and search for a new spot for the other element instead.
uint32_t otherHomeBucket = (uint32_t)otherKey & (Size - 1);
if (otherHomeBucket > homeBucket) {
template<TBType Type>
TBTable<Type>* get(Key key) {
for (const Entry* entry = &hashTable[(uint32_t)key & (Size - 1)]; ; ++entry) {
template<TBType Type>
TBTable<Type>* get(Key key) {
for (const Entry* entry = &hashTable[(uint32_t)key & (Size - 1)]; ; ++entry) {
bool blackStronger = (pos.material_key() != entry->key);
int flipColor = (symmetricBlackToMove || blackStronger) * 8;
bool blackStronger = (pos.material_key() != entry->key);
int flipColor = (symmetricBlackToMove || blackStronger) * 8;
int stm = (symmetricBlackToMove || blackStronger) ^ pos.side_to_move();
// For pawns, TB files store 4 separate tables according if leading pawn is on
int stm = (symmetricBlackToMove || blackStronger) ^ pos.side_to_move();
// For pawns, TB files store 4 separate tables according if leading pawn is on
std::swap(squares[0], *std::max_element(squares, squares + leadPawnsCnt, pawns_comp));
std::swap(squares[0], *std::max_element(squares, squares + leadPawnsCnt, pawns_comp));
// Then we reorder the pieces to have the same sequence as the one stored
// in pieces[i]: the sequence that ensures the best compression.
// Then we reorder the pieces to have the same sequence as the one stored
// in pieces[i]: the sequence that ensures the best compression.
if (d->pieces[i] == pieces[j])
{
std::swap(pieces[i], pieces[j]);
if (d->pieces[i] == pieces[j])
{
std::swap(pieces[i], pieces[j]);
// the triangle A1-D1-D4.
if (file_of(squares[0]) > FILE_D)
for (int i = 0; i < size; ++i)
// the triangle A1-D1-D4.
if (file_of(squares[0]) > FILE_D)
for (int i = 0; i < size; ++i)
// Encode leading pawns starting with the one with minimum MapPawns[] and
// proceeding in ascending order.
// Encode leading pawns starting with the one with minimum MapPawns[] and
// proceeding in ascending order.
// piece is below RANK_5.
if (rank_of(squares[0]) > RANK_4)
for (int i = 0; i < size; ++i)
// piece is below RANK_5.
if (rank_of(squares[0]) > RANK_4)
for (int i = 0; i < size; ++i)
// Look for the first piece of the leading group not on the A1-D4 diagonal
// and ensure it is mapped below the diagonal.
// Look for the first piece of the leading group not on the A1-D4 diagonal
// and ensure it is mapped below the diagonal.