stellar

Improve transposition table, add stats info

4 files changed, 74 insertions(+), 7 deletions(-)

diff --git a/ CMakeLists.txt b/ CMakeLists.txt

@@ -3,7 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON) project( Stellar

VERSION 1.3.8

VERSION 1.3.9

DESCRIPTION "Chess engine written in C++" HOMEPAGE_URL https://git.dimitrijedobrota.com/stellar.git LANGUAGES CXX

diff --git a/ src/engine/CMakeLists.txt b/ src/engine/CMakeLists.txt

@@ -4,6 +4,10 @@ add_executable(engine uci.cpp )

option(STELLAR_STATS "Provide stats for analysis" OFF)

if(STELLAR_STATS)

add_definitions(-DUSE_STATS)

endif()

target_link_libraries(engine PRIVATE Stellar_version

diff --git a/ src/engine/engine.cpp b/ src/engine/engine.cpp

@@ -45,10 +45,44 @@ template <U64 size> class TTable_internal { public: static inline constexpr const int16_t unknown = 32500;

static void clear() { memset(table.data(), 0x00, size * sizeof(Hashe)); };

static void clear() {

memset(table.data(), 0x00, size * sizeof(Hashe));

#ifdef USE_STATS

accessed = 0, rewrite = 0, miss = 0;

#endif

};

#ifdef USE_STATS

static void print() {

std::cout << "Transposition table: " << std::endl;

std::cout << "\tSize: " << size << " entries (" << sizeof(Hashe) << "B per entry)" << std::endl;

std::cout << "\tSize: " << std::fixed << std::setprecision(2)

<< (double)size * sizeof(Hashe) / (1 << 20) << "MB" << std::endl;

std::cout << "\tReads: " << accessed << std::endl;

std::cout << "\tMisses: " << miss << "(" << (double)miss / accessed << "%)" << std::endl;

std::cout << "\tRewrite: " << rewrite << std::endl;

std::cout << "\tUsed " << (double)used() / size << "%" << std::endl;

}

static U64 used() {

U64 res = 0;

for (int i = 0; i < size; i++) {

if (table[i].key) res++;

}

return res;

}

#endif

static int16_t read(const Board &board, int ply, Move *best, int16_t alpha, int16_t beta, uint8_t depth) { U64 hash = board.get_hash();

const Hashe &phashe = table[hash % table.size()];

const Hashe &phashe = table[hash % size];

#ifdef USE_STATS

accessed++;

#endif

if (phashe.key == hash) { if (phashe.depth >= depth) { int16_t score = phashe.score;

@@ -62,26 +96,54 @@ template <U64 size> class TTable_internal { } *best = phashe.best; }

#ifdef USE_STATS

else {

miss++;

}

#endif

return unknown; } static void write(const Board &board, int ply, Move best, int16_t score, uint8_t depth, Hashe::Flag flag) { U64 hash = board.get_hash();

Hashe &phashe = table[hash % table.size()];

Hashe &phashe = table[hash % size];

if (score < -MATE_SCORE) score += ply; if (score > MATE_SCORE) score -= ply;

if (phashe.key == hash) {

if (phashe.depth > depth) return;

}

#ifdef USE_STATS

else {

rewrite++;

}

#endif

phashe = {hash, best, depth, score, flag}; } private: static std::array<Hashe, size> table;

#ifdef USE_STATS

static U64 accessed, rewrite, miss;

#endif

}; template <U64 size> std::array<Hashe, size> TTable_internal<size>::table;

#ifdef USE_STATS

template <U64 size> U64 TTable_internal<size>::accessed = 0;

template <U64 size> U64 TTable_internal<size>::rewrite = 0;

template <U64 size> U64 TTable_internal<size>::miss = 0;

#endif

using TTable = TTable_internal<C64(0x2000023)>;

TTable ttable;

class PVTable { public: Move best(uint8_t ply = 0) { return table[0][ply]; }

@@ -107,9 +169,6 @@ std::ostream &operator<<(std::ostream &os, const PVTable &pvtable) { return os; }

using TTable = TTable_internal<C64(0x2FB4377)>;

TTable ttable;

static const uci::Settings *settings = nullptr; static Board board; static repetition::Table rtable;

@@ -476,5 +535,8 @@ int main() { attack::init(); zobrist::init(); uci::loop();

#ifdef USE_STATS

engine::ttable.print();

#endif

return 0; }

diff --git a/ src/perft/perft.cpp b/ src/perft/perft.cpp

@@ -82,6 +82,7 @@ class Perft { void score(const Board &board, Move move) { local.node++;

std::cout << std::setw(16) << std::hex << board.get_hash() << std::endl;

#ifdef USE_FULL_COUNT if (board.is_check()) local.check++; if (move.is_capture()) local.capture++;