diff options
Diffstat (limited to 'include/tt.h')
| -rw-r--r-- | include/tt.h | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/include/tt.h b/include/tt.h index b8e1a2e..60b9b66 100644 --- a/include/tt.h +++ b/include/tt.h @@ -28,6 +28,10 @@ enum TT_FLAG { TT_EXACT, TT_LOWERBOUND, TT_UPPERBOUND }; +#ifdef RECORD_PV +#include <pv.h> +#endif + typedef struct tt_node_s { uint16_t gen; uint64_t key; @@ -35,6 +39,10 @@ typedef struct tt_node_s { uint8_t depth; float value; action_t action; +#ifdef RECORD_PV + // use for generating training data only + pv_leaf_t leaf; +#endif } tt_entry_t; // =================================================================== @@ -48,15 +56,25 @@ typedef struct tt_node_s { // Methods // =================================================================== -// Bump the generation counter, invalidating all entries (memsets the -// table on wraparound). Called from negamax_init when the board size -// (and hence the zobrist table) changes; entries are otherwise kept -// across plies on purpose (see negamax.c). +// Bump the generation counter, invalidating all entries. Called from +// negamax_init when the board size (and hence the zobrist table) changes; +// entries are otherwise kept across plies on purpose (see negamax.c). int tt_init(void); tt_entry_t *tt_seek(const uint64_t key); -int tt_insert(const uint64_t key, const enum TT_FLAG flag, const uint8_t depth, - const float value, const action_t action); +// Store a search result for `key', returning the entry it was written to, or +// NULL when the replacement policy keeps the current occupant instead. +// +// Replacement policy per slot: +// +// - generation and key match: always update +// +// - otherwise (empty slot, stale generation, or a different key): replace the +// occupant unless it is a deeper search of a different position, which is +// kept. +tt_entry_t *tt_store(const uint64_t key, const enum TT_FLAG flag, + const uint8_t depth, const float value, + const action_t action); #endif |