ben_bot::TranspositionTable Class Reference

#include <libbenbot/data-structures/TranspositionTable.hpp>

Public Types
using	ProbedEval = std::pair<eval::Value, EvalType>

Public Member Functions
	TranspositionTable (const size_t initialSize=16uz)
	TranspositionTable (const TranspositionTable &)=delete
	TranspositionTable (TranspositionTable &&other) noexcept
	~TranspositionTable ()
void	clear ()
auto	find (const Position &pos) const -> std::optional< TTData >
auto	get_best_response (const Position &pos, Move move) const -> std::optional< Move >
auto	hashfull () const -> size_t
void	new_search () noexcept
TranspositionTable &	operator= (const TranspositionTable &)=delete
TranspositionTable &	operator= (TranspositionTable &&other) noexcept
void	prefetch (const Position &pos) const noexcept
auto	probe_eval (const Position &pos, size_t depth, const search::Bounds &bounds) const -> std::optional< ProbedEval >
void	resize (size_t sizeMB)
void	store (const Position &pos, const TTData &record)

Detailed Description

The transposition table data structure.

Definition at line 91 of file TranspositionTable.hpp.

Member Typedef Documentation

ProbedEval

using ben_bot::TranspositionTable::ProbedEval = std::pair<eval::Value, EvalType>

Represents a probed evaluation from the table. This is a pair of the evaluation value and the value type.

Definition at line 114 of file TranspositionTable.hpp.

Constructor & Destructor Documentation

TranspositionTable() [1/3]

ben_bot::TranspositionTable::TranspositionTable ( const size_t initialSize = 16uz )

inlineexplicit

Definition at line 93 of file TranspositionTable.hpp.

~TranspositionTable()

ben_bot::TranspositionTable::~TranspositionTable ( )

inline

Definition at line 98 of file TranspositionTable.hpp.

TranspositionTable() [2/3]

ben_bot::TranspositionTable::TranspositionTable ( const TranspositionTable & )

delete

TranspositionTable() [3/3]

ben_bot::TranspositionTable::TranspositionTable ( TranspositionTable && other )

noexcept

Member Function Documentation

clear()

void ben_bot::TranspositionTable::clear

(

)

Clears the contents of the table. Note that no memory is freed.

find()

auto ben_bot::TranspositionTable::find ( const Position & pos ) const -> std::optional< TTData >

nodiscard

Retrieves the stored record for the given position, or nullopt if the given position isn't in the table.

get_best_response()

auto ben_bot::TranspositionTable::get_best_response ( const Position & pos, Move move ) const -> std::optional< Move >

nodiscard

Returns the opponent's best response to the given move, if one is recorded.

hashfull()

auto ben_bot::TranspositionTable::hashfull ( ) const -> size_t

nodiscard

Returns an estimate of the percentage of entries (permille) that have been written to during this search.

new_search()

void ben_bot::TranspositionTable::new_search ( )

noexcept

This must be called at the beginning of a new search to keep track of entry aging.

operator=() [1/2]

TranspositionTable & ben_bot::TranspositionTable::operator= ( const TranspositionTable & )

delete

operator=() [2/2]

TranspositionTable & ben_bot::TranspositionTable::operator= ( TranspositionTable && other )

noexcept

prefetch()

void ben_bot::TranspositionTable::prefetch ( const Position & pos ) const

noexcept

Hints to the CPU to prefetch the memory bucket containing data for the given position. This function returns immediately.

probe_eval()

auto ben_bot::TranspositionTable::probe_eval ( const Position & pos, size_t depth, const search::Bounds & bounds ) const -> std::optional< ProbedEval >

nodiscard

Similar to find(), this function instead probes for an evaluation value of the given position, searched to at least the given depth and honoring the given search bounds.

Returns pair of the evaluation value and the value type.

resize()

void ben_bot::TranspositionTable::resize

(

size_t

sizeMB

)

Resizes the table to a given size in megabytes.

Exceptions

std::bad_alloc

An exception is thrown if sizeMB is 0 or if the allocation fails.

store()

void ben_bot::TranspositionTable::store	(	const Position &	pos,
		const TTData &	record )

Stores a record for a given position.

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The documentation for this class was generated from the following file:

• libbenbot/include/libbenbot/data-structures/TranspositionTable.hpp