#include <algorithm>
#include <atomic>
#include <cstdint>
-#include <cstring> // For std::memset
+#include <cstring> // For std::memset and std::memcpy
#include <deque>
#include <fstream>
#include <iostream>
namespace {
+constexpr int TBPIECES = 6; // Max number of supported pieces
+
+enum TBType { WDL, DTZ }; // Used as template parameter
+
// 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, SingleValue = 128 };
static_assert(sizeof(LR) == 3, "LR tree entry must be 3 bytes");
-constexpr int TBPIECES = 6;
-
struct PairsData {
int flags;
size_t sizeofBlock; // Block size in bytes
Piece pieces[TBPIECES]; // Position pieces: the order of pieces defines the groups
uint64_t groupIdx[TBPIECES+1]; // Start index used for the encoding of the group's pieces
int groupLen[TBPIECES+1]; // Number of pieces in a given group: KRKN -> (3, 1)
+ uint16_t map_idx[4]; // WDLWin, WDLLoss, WDLCursedWin, WDLBlessedLoss (used in DTZ)
};
-// Helper struct to avoid manually defining entry copy constructor as we
-// should because the default one is not compatible with std::atomic_bool.
-struct Atomic {
- Atomic() = default;
- Atomic(const Atomic& e) { ready = e.ready.load(); } // MSVC 2013 wants assignment within body
- std::atomic_bool ready;
-};
-
-// We define types for the different parts of the WDLEntry and DTZEntry with
-// corresponding specializations for pieces or pawns.
-
-struct WDLEntryPiece {
- PairsData* precomp;
-};
+template<TBType Type>
+struct TBEntry {
+ typedef typename std::conditional<Type == WDL, WDLScore, int>::type Result;
-struct WDLEntryPawn {
- uint8_t pawnCount[2]; // [Lead color / other color]
- WDLEntryPiece file[2][4]; // [wtm / btm][FILE_A..FILE_D]
-};
-
-struct DTZEntryPiece {
- PairsData* precomp;
- uint16_t map_idx[4]; // WDLWin, WDLLoss, WDLCursedWin, WDLBlessedLoss
- uint8_t* map;
-};
-
-struct DTZEntryPawn {
- uint8_t pawnCount[2];
- DTZEntryPiece file[4];
- uint8_t* map;
-};
+ static constexpr int Sides = Type == WDL ? 2 : 1;
-struct TBEntry : public Atomic {
+ std::atomic_bool ready;
void* baseAddress;
+ uint8_t* map;
uint64_t mapping;
Key key;
Key key2;
int pieceCount;
bool hasPawns;
bool hasUniquePieces;
-};
+ uint8_t pawnCount[2]; // [Lead color / other color]
+ PairsData items[Sides][4]; // [wtm / btm][FILE_A..FILE_D or 0]
-// Now the main types: WDLEntry and DTZEntry
-struct WDLEntry : public TBEntry {
- WDLEntry(const std::string& code);
- ~WDLEntry();
- union {
- WDLEntryPiece pieceTable[2]; // [wtm / btm]
- WDLEntryPawn pawnTable;
- };
-};
+ PairsData* get(int stm, int f) {
+ return &items[stm % Sides][hasPawns ? f : 0];
+ }
-struct DTZEntry : public TBEntry {
- DTZEntry(const WDLEntry& wdl);
- ~DTZEntry();
- union {
- DTZEntryPiece pieceTable;
- DTZEntryPawn pawnTable;
- };
+ TBEntry() : ready(false), baseAddress(nullptr) {}
+ explicit TBEntry(const std::string& code);
+ explicit TBEntry(const TBEntry<WDL>& wdl);
+ ~TBEntry();
};
-typedef decltype(WDLEntry::pieceTable) WDLPieceTable;
-typedef decltype(DTZEntry::pieceTable) DTZPieceTable;
-typedef decltype(WDLEntry::pawnTable ) WDLPawnTable;
-typedef decltype(DTZEntry::pawnTable ) DTZPawnTable;
+template<>
+TBEntry<WDL>::TBEntry(const std::string& code) : TBEntry() {
+
+ StateInfo st;
+ Position pos;
+
+ key = pos.set(code, WHITE, &st).material_key();
+ pieceCount = popcount(pos.pieces());
+ hasPawns = pos.pieces(PAWN);
+
+ hasUniquePieces = false;
+ for (Color c = WHITE; c <= BLACK; ++c)
+ for (PieceType pt = PAWN; pt < KING; ++pt)
+ if (popcount(pos.pieces(c, pt)) == 1)
+ hasUniquePieces = true;
+
+ if (hasPawns) {
+ // Set the leading color. In case both sides have pawns the leading color
+ // is the side with less pawns because this leads to better compression.
+ bool c = !pos.count<PAWN>(BLACK)
+ || ( pos.count<PAWN>(WHITE)
+ && pos.count<PAWN>(BLACK) >= pos.count<PAWN>(WHITE));
-auto item(WDLPieceTable& e, int stm, int ) -> decltype(e[stm])& { return e[stm]; }
-auto item(DTZPieceTable& e, int , int ) -> decltype(e)& { return e; }
-auto item(WDLPawnTable& e, int stm, int f) -> decltype(e.file[stm][f])& { return e.file[stm][f]; }
-auto item(DTZPawnTable& e, int , int f) -> decltype(e.file[f])& { return e.file[f]; }
+ pawnCount[0] = pos.count<PAWN>(c ? WHITE : BLACK);
+ pawnCount[1] = pos.count<PAWN>(c ? BLACK : WHITE);
+ }
-template<typename E> struct Ret { typedef int type; };
-template<> struct Ret<WDLEntry> { typedef WDLScore type; };
+ key2 = pos.set(code, BLACK, &st).material_key();
+}
+
+template<>
+TBEntry<DTZ>::TBEntry(const TBEntry<WDL>& wdl) : TBEntry() {
+
+ key = wdl.key;
+ key2 = wdl.key2;
+ pieceCount = wdl.pieceCount;
+ hasPawns = wdl.hasPawns;
+ hasUniquePieces = wdl.hasUniquePieces;
+
+ if (hasPawns) {
+ pawnCount[0] = wdl.pawnCount[0];
+ pawnCount[1] = wdl.pawnCount[1];
+ }
+}
int MapPawns[SQUARE_NB];
int MapB1H1H7[SQUARE_NB];
class HashTable {
- typedef std::pair<WDLEntry*, DTZEntry*> EntryPair;
+ typedef std::pair<TBEntry<WDL>*, TBEntry<DTZ>*> EntryPair;
typedef std::pair<Key, EntryPair> Entry;
static constexpr int TBHASHBITS = 10;
Entry hashTable[1 << TBHASHBITS][HSHMAX];
- std::deque<WDLEntry> wdlTable;
- std::deque<DTZEntry> dtzTable;
+ std::deque<TBEntry<WDL>> wdlTable;
+ std::deque<TBEntry<DTZ>> dtzTable;
- void insert(Key key, WDLEntry* wdl, DTZEntry* dtz) {
- Entry* entry = hashTable[key >> (64 - TBHASHBITS)];
-
- for (int i = 0; i < HSHMAX; ++i, ++entry)
- if (!entry->second.first || entry->first == key) {
- *entry = std::make_pair(key, std::make_pair(wdl, dtz));
+ void insert(Key key, TBEntry<WDL>* wdl, TBEntry<DTZ>* dtz) {
+ for (Entry& entry : hashTable[key >> (64 - TBHASHBITS)])
+ if (!entry.second.first || entry.first == key) {
+ entry = std::make_pair(key, std::make_pair(wdl, dtz));
return;
}
}
public:
- template<typename E, int I = std::is_same<E, WDLEntry>::value ? 0 : 1>
- E* get(Key key) {
- Entry* entry = hashTable[key >> (64 - TBHASHBITS)];
-
- for (int i = 0; i < HSHMAX; ++i, ++entry)
- if (entry->first == key)
- return std::get<I>(entry->second);
-
- return nullptr;
- }
-
- void clear() {
- std::memset(hashTable, 0, sizeof(hashTable));
- wdlTable.clear();
- dtzTable.clear();
- }
- size_t size() const { return wdlTable.size(); }
- void insert(const std::vector<PieceType>& pieces);
+ template<TBType Type>
+ TBEntry<Type>* get(Key key) {
+ for (Entry& entry : hashTable[key >> (64 - TBHASHBITS)])
+ if (entry.first == key)
+ return std::get<Type>(entry.second);
+
+ return nullptr;
+ }
+
+ void clear() {
+ memset(hashTable, 0, sizeof(hashTable));
+ wdlTable.clear();
+ dtzTable.clear();
+ }
+ size_t size() const { return wdlTable.size(); }
+ void insert(const std::vector<PieceType>& pieces);
};
HashTable EntryTable;
std::string TBFile::Paths;
-WDLEntry::WDLEntry(const std::string& code) {
-
- StateInfo st;
- Position pos;
-
- memset(this, 0, sizeof(WDLEntry));
-
- ready = false;
- key = pos.set(code, WHITE, &st).material_key();
- pieceCount = popcount(pos.pieces());
- hasPawns = pos.pieces(PAWN);
-
- for (Color c = WHITE; c <= BLACK; ++c)
- for (PieceType pt = PAWN; pt < KING; ++pt)
- if (popcount(pos.pieces(c, pt)) == 1)
- hasUniquePieces = true;
-
- if (hasPawns) {
- // Set the leading color. In case both sides have pawns the leading color
- // is the side with less pawns because this leads to better compression.
- bool c = !pos.count<PAWN>(BLACK)
- || ( pos.count<PAWN>(WHITE)
- && pos.count<PAWN>(BLACK) >= pos.count<PAWN>(WHITE));
-
- pawnTable.pawnCount[0] = pos.count<PAWN>(c ? WHITE : BLACK);
- pawnTable.pawnCount[1] = pos.count<PAWN>(c ? BLACK : WHITE);
- }
-
- key2 = pos.set(code, BLACK, &st).material_key();
-}
-
-WDLEntry::~WDLEntry() {
-
- if (baseAddress)
- TBFile::unmap(baseAddress, mapping);
-
- for (int i = 0; i < 2; ++i)
- if (hasPawns)
- for (File f = FILE_A; f <= FILE_D; ++f)
- delete pawnTable.file[i][f].precomp;
- else
- delete pieceTable[i].precomp;
-}
-
-DTZEntry::DTZEntry(const WDLEntry& wdl) {
-
- memset(this, 0, sizeof(DTZEntry));
-
- ready = false;
- key = wdl.key;
- key2 = wdl.key2;
- pieceCount = wdl.pieceCount;
- hasPawns = wdl.hasPawns;
- hasUniquePieces = wdl.hasUniquePieces;
-
- if (hasPawns) {
- pawnTable.pawnCount[0] = wdl.pawnTable.pawnCount[0];
- pawnTable.pawnCount[1] = wdl.pawnTable.pawnCount[1];
- }
-}
-
-DTZEntry::~DTZEntry() {
-
+template<TBType Type>
+TBEntry<Type>::~TBEntry() {
if (baseAddress)
TBFile::unmap(baseAddress, mapping);
-
- if (hasPawns)
- for (File f = FILE_A; f <= FILE_D; ++f)
- delete pawnTable.file[f].precomp;
- else
- delete pieceTable.precomp;
}
void HashTable::insert(const std::vector<PieceType>& pieces) {
return d->btree[sym].get<LR::Value>();
}
-bool check_dtz_stm(WDLEntry*, int, File) { return true; }
-
-bool check_dtz_stm(DTZEntry* entry, int stm, File f) {
+bool check_dtz_stm(TBEntry<WDL>*, int, File) { return true; }
- int flags = entry->hasPawns ? entry->pawnTable.file[f].precomp->flags
- : entry->pieceTable.precomp->flags;
+bool check_dtz_stm(TBEntry<DTZ>* entry, int stm, File f) {
+ int flags = entry->get(stm, f)->flags;
return (flags & TBFlag::STM) == stm
|| ((entry->key == entry->key2) && !entry->hasPawns);
}
// values 0, 1, 2, ... in order of decreasing frequency. This is done for each
// of the four WDLScore values. The mapping information necessary to reconstruct
// the original values is stored in the TB file and read during map[] init.
-WDLScore map_score(WDLEntry*, File, int value, WDLScore) { return WDLScore(value - 2); }
+WDLScore map_score(TBEntry<WDL>*, File, int value, WDLScore) { return WDLScore(value - 2); }
-int map_score(DTZEntry* entry, File f, int value, WDLScore wdl) {
+int map_score(TBEntry<DTZ>* entry, File f, int value, WDLScore wdl) {
constexpr int WDLMap[] = { 1, 3, 0, 2, 0 };
- int flags = entry->hasPawns ? entry->pawnTable.file[f].precomp->flags
- : entry->pieceTable.precomp->flags;
-
- uint8_t* map = entry->hasPawns ? entry->pawnTable.map
- : entry->pieceTable.map;
+ int flags = entry->get(0, f)->flags;
- uint16_t* idx = entry->hasPawns ? entry->pawnTable.file[f].map_idx
- : entry->pieceTable.map_idx;
+ uint8_t* map = entry->map;
+ uint16_t* idx = entry->get(0, f)->map_idx;
if (flags & TBFlag::Mapped)
value = map[idx[WDLMap[wdl + 2]] + value];
//
// idx = Binomial[1][s1] + Binomial[2][s2] + ... + Binomial[k][sk]
//
-template<typename Entry, typename T = typename Ret<Entry>::type>
-T do_probe_table(const Position& pos, Entry* entry, WDLScore wdl, ProbeState* result) {
-
- constexpr bool IsWDL = std::is_same<Entry, WDLEntry>::value;
+template<TBType Type, typename T = typename TBEntry<Type>::Result>
+T do_probe_table(const Position& pos, TBEntry<Type>* entry, WDLScore wdl, ProbeState* result) {
Square squares[TBPIECES];
Piece pieces[TBPIECES];
// In all the 4 tables, pawns are at the beginning of the piece sequence and
// their color is the reference one. So we just pick the first one.
- Piece pc = Piece(item(entry->pawnTable, 0, 0).precomp->pieces[0] ^ flipColor);
+ Piece pc = Piece(entry->get(0, 0)->pieces[0] ^ flipColor);
assert(type_of(pc) == PAWN);
tbFile = file_of(squares[0]);
if (tbFile > FILE_D)
tbFile = file_of(squares[0] ^ 7); // Horizontal flip: SQ_H1 -> SQ_A1
-
- d = item(entry->pawnTable , stm, tbFile).precomp;
- } else
- d = item(entry->pieceTable, stm, tbFile).precomp;
+ }
// DTZ tables are one-sided, i.e. they store positions only for white to
// move or only for black to move, so check for side to move to be stm,
// early exit otherwise.
- if (!IsWDL && !check_dtz_stm(entry, stm, tbFile))
+ if (Type == DTZ && !check_dtz_stm(entry, stm, tbFile))
return *result = CHANGE_STM, T();
// Now we are ready to get all the position pieces (but the lead pawns) and
assert(size >= 2);
+ d = entry->get(stm, tbFile);
+
// Then we reorder the pieces to have the same sequence as the one stored
- // in precomp->pieces[i]: the sequence that ensures the best compression.
+ // in pieces[i]: the sequence that ensures the best compression.
for (int i = leadPawnsCnt; i < size; ++i)
for (int j = i; j < size; ++j)
if (d->pieces[i] == pieces[j])
Square* groupSq = squares + d->groupLen[0];
// Encode remainig pawns then pieces according to square, in ascending order
- bool remainingPawns = entry->hasPawns && entry->pawnTable.pawnCount[1];
+ bool remainingPawns = entry->hasPawns && entry->pawnCount[1];
while (d->groupLen[++next])
{
//
// The actual grouping depends on the TB generator and can be inferred from the
// sequence of pieces in piece[] array.
-template<typename T>
-void set_groups(T& e, PairsData* d, int order[], File f) {
+template<TBType Type>
+void set_groups(TBEntry<Type>& e, PairsData* d, int order[], File f) {
int n = 0, firstLen = e.hasPawns ? 0 : e.hasUniquePieces ? 3 : 2;
d->groupLen[n] = 1;
// pawns/pieces -> remainig pawns -> remaining pieces. In particular the
// first group is at order[0] position and the remaining pawns, when present,
// are at order[1] position.
- bool pp = e.hasPawns && e.pawnTable.pawnCount[1]; // Pawns on both sides
+ bool pp = e.hasPawns && e.pawnCount[1]; // Pawns on both sides
int next = pp ? 2 : 1;
int freeSquares = 64 - d->groupLen[0] - (pp ? d->groupLen[1] : 0);
uint64_t idx = 1;
return data + d->symlen.size() * sizeof(LR) + (d->symlen.size() & 1);
}
-template<typename T>
-uint8_t* set_dtz_map(WDLEntry&, T&, uint8_t*, File) { return nullptr; }
+uint8_t* set_dtz_map(TBEntry<WDL>&, uint8_t*, File) { return nullptr; }
-template<typename T>
-uint8_t* set_dtz_map(DTZEntry&, T& p, uint8_t* data, File maxFile) {
+uint8_t* set_dtz_map(TBEntry<DTZ>& e, uint8_t* data, File maxFile) {
- p.map = data;
+ e.map = data;
for (File f = FILE_A; f <= maxFile; ++f) {
- if (item(p, 0, f).precomp->flags & TBFlag::Mapped)
+ if (e.get(0, f)->flags & TBFlag::Mapped)
for (int i = 0; i < 4; ++i) { // Sequence like 3,x,x,x,1,x,0,2,x,x
- item(p, 0, f).map_idx[i] = (uint16_t)(data - p.map + 1);
+ e.get(0, f)->map_idx[i] = (uint16_t)(data - e.map + 1);
data += *data + 1;
}
}
return data += (uintptr_t)data & 1; // Word alignment
}
-template<typename Entry, typename T>
-void do_init(Entry& e, T& p, uint8_t* data) {
-
- const bool IsWDL = std::is_same<Entry, WDLEntry>::value;
+template<TBType Type>
+void do_init(TBEntry<Type>& e, uint8_t* data) {
PairsData* d;
data++; // First byte stores flags
- const int sides = IsWDL && (e.key != e.key2) ? 2 : 1;
+ const int sides = Type == WDL && (e.key != e.key2) ? 2 : 1;
const File maxFile = e.hasPawns ? FILE_D : FILE_A;
- bool pp = e.hasPawns && e.pawnTable.pawnCount[1]; // Pawns on both sides
+ bool pp = e.hasPawns && e.pawnCount[1]; // Pawns on both sides
- assert(!pp || e.pawnTable.pawnCount[0]);
+ assert(!pp || e.pawnCount[0]);
for (File f = FILE_A; f <= maxFile; ++f) {
for (int i = 0; i < sides; i++)
- item(p, i, f).precomp = new PairsData();
+ *e.get(i, f) = PairsData();
int order[][2] = { { *data & 0xF, pp ? *(data + 1) & 0xF : 0xF },
{ *data >> 4, pp ? *(data + 1) >> 4 : 0xF } };
for (int k = 0; k < e.pieceCount; ++k, ++data)
for (int i = 0; i < sides; i++)
- item(p, i, f).precomp->pieces[k] = Piece(i ? *data >> 4 : *data & 0xF);
+ e.get(i, f)->pieces[k] = Piece(i ? *data >> 4 : *data & 0xF);
for (int i = 0; i < sides; ++i)
- set_groups(e, item(p, i, f).precomp, order[i], f);
+ set_groups(e, e.get(i, f), order[i], f);
}
data += (uintptr_t)data & 1; // Word alignment
for (File f = FILE_A; f <= maxFile; ++f)
for (int i = 0; i < sides; i++)
- data = set_sizes(item(p, i, f).precomp, data);
+ data = set_sizes(e.get(i, f), data);
- if (!IsWDL)
- data = set_dtz_map(e, p, data, maxFile);
+ if (Type == DTZ)
+ data = set_dtz_map(e, data, maxFile);
for (File f = FILE_A; f <= maxFile; ++f)
for (int i = 0; i < sides; i++) {
- (d = item(p, i, f).precomp)->sparseIndex = (SparseEntry*)data;
+ (d = e.get(i, f))->sparseIndex = (SparseEntry*)data;
data += d->sparseIndexSize * sizeof(SparseEntry);
}
for (File f = FILE_A; f <= maxFile; ++f)
for (int i = 0; i < sides; i++) {
- (d = item(p, i, f).precomp)->blockLength = (uint16_t*)data;
+ (d = e.get(i, f))->blockLength = (uint16_t*)data;
data += d->blockLengthSize * sizeof(uint16_t);
}
for (File f = FILE_A; f <= maxFile; ++f)
for (int i = 0; i < sides; i++) {
data = (uint8_t*)(((uintptr_t)data + 0x3F) & ~0x3F); // 64 byte alignment
- (d = item(p, i, f).precomp)->data = data;
+ (d = e.get(i, f))->data = data;
data += d->blocksNum * d->sizeofBlock;
}
}
-template<typename Entry>
-void* init(Entry& e, const Position& pos) {
-
- constexpr bool IsWDL = std::is_same<Entry, WDLEntry>::value;
+template<TBType Type>
+void* init(TBEntry<Type>& e, const Position& pos) {
static Mutex mutex;
{ 0x71, 0xE8, 0x23, 0x5D } };
fname = (e.key == pos.material_key() ? w + 'v' + b : b + 'v' + w)
- + (IsWDL ? ".rtbw" : ".rtbz");
+ + (Type == WDL ? ".rtbw" : ".rtbz");
- uint8_t* data = TBFile(fname).map(&e.baseAddress, &e.mapping, TB_MAGIC[IsWDL]);
+ uint8_t* data = TBFile(fname).map(&e.baseAddress, &e.mapping,
+ TB_MAGIC[Type == WDL]);
if (data)
- e.hasPawns ? do_init(e, e.pawnTable, data) : do_init(e, e.pieceTable, data);
+ do_init(e, data);
e.ready.store(true, std::memory_order_release);
return e.baseAddress;
}
-template<typename E, typename T = typename Ret<E>::type>
+template<TBType Type, typename T = typename TBEntry<Type>::Result>
T probe_table(const Position& pos, ProbeState* result, WDLScore wdl = WDLDraw) {
if (!(pos.pieces() ^ pos.pieces(KING)))
return T(WDLDraw); // KvK
- E* entry = EntryTable.get<E>(pos.material_key());
+ TBEntry<Type>* entry = EntryTable.get<Type>(pos.material_key());
if (!entry || !init(*entry, pos))
return *result = FAIL, T();
value = bestValue;
else
{
- value = probe_table<WDLEntry>(pos, result);
+ value = probe_table<WDL>(pos, result);
if (*result == FAIL)
return WDLDraw;
if (*result == ZEROING_BEST_MOVE)
return dtz_before_zeroing(wdl);
- int dtz = probe_table<DTZEntry>(pos, result, wdl);
+ int dtz = probe_table<DTZ>(pos, result, wdl);
if (*result == FAIL)
return 0;
projects / stockfish / blobdiff