move_picker: swap-and-reduce for TT move - #191
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| private: | ||
| movegen::Move pickMove(uint16_t pos) |
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might improve performance a bit - it's a smaller method, so most likely worth it :)
Suggested change
| movegen::Move pickMove(uint16_t pos) | |
| inline movegen::Move pickMove(uint16_t pos) |
| return std::nullopt; | ||
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| m_moves.nullifyMove(i); | ||
| assert(!m_moves[m_syzygyHead].isNull()); |
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Don't think we need to check for null anymore - movegen does not generate nullmoves :)
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| for (uint16_t i = 0; i < m_moves.count(); i++) { | ||
| for (uint16_t i = 0; i < m_size; i++) { | ||
| if (!m_moves[i].isNull() && m_moves[i] == *m_ttMove) { |
Owner
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No need to check for null-move anymore :) (goes for all the picking now stages)
Suggested change
| if (!m_moves[i].isNull() && m_moves[i] == *m_ttMove) { | |
| if (m_moves[i] == *m_ttMove) { |
| std::optional<movegen::Move> bestMove { std::nullopt }; | ||
| int32_t bestScore = std::numeric_limits<int32_t>::min(); | ||
| uint16_t bestMoveIndex {}; | ||
| bool foundBestMove { false }; |
Owner
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Probably cleaner to use a std::optional for the index as it's used to pick the move :)
| std::optional<movegen::Move> bestMove {}; | ||
| int32_t bestScore = std::numeric_limits<int32_t>::min(); | ||
| uint16_t bestMoveIndex {}; | ||
| bool foundBestMove { false }; |
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| movegen::ValidMoves m_moves {}; | ||
| std::array<int32_t, s_maxMoves> m_scores {}; | ||
| uint16_t m_size {}; |
Owner
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maybe rename to align with the head used for syzygy :)
Suggested change
| uint16_t m_size {}; | |
| uint16_t m_tail {}; |
| movegen::ValidMoves m_moves {}; | ||
| std::array<int32_t, s_maxMoves> m_scores {}; | ||
| uint16_t m_size {}; | ||
| uint16_t m_syzygyHead {}; |
Owner
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I'd add a comment to each of these to explain how they're not connected (syzygy we pick from the front and otherwise we move the picked move to the back and decrease the tail etc)
| private: | ||
| movegen::Move pickMove(uint16_t pos) | ||
| { | ||
| auto pickedMove = m_moves[pos]; |
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Suggested change
| auto pickedMove = m_moves[pos]; | |
| const auto pickedMove = m_moves[pos]; |
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| } | ||
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| constexpr std::optional<movegen::Move> pickTtMove() | ||
| constexpr std::optional<movegen::Move> |
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Instead of leaving null 'holes' in the move picker, we move picked moves to the back of the array of all moves and reduce the size accordingly. Bench has changed, because quiet moves at the root have no history, and are therefore picked in their order of generation. So changing the move order has large effects down the search. Bench 1446371
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Instead of leaving null 'holes' in the move picker, we move picked moves to the back of the array of all moves and reduce the size accordingly.
Bench has changed, because quiet moves at the root have no history, and therefore picked in their order of generation. So changing the move order has large effects down the search.
https://openbench.bunny.beer/test/564/
Bench 1513294