X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.h;h=5d0df726239cabb66cb13628ac3523e9fb676c9c;hp=e838b0902fb9c140c8cd7bea1c551a00d4878213;hb=a0005ba45f7d5c97a096b79065c0b83ae3d81afa;hpb=60b5da4cc8639d907d0beeee67055271b464779f diff --git a/src/tt.h b/src/tt.h index e838b090..5d0df726 100644 --- a/src/tt.h +++ b/src/tt.h @@ -70,10 +70,23 @@ private: uint32_t data; int16_t value_; int16_t depth_; - uint32_t pad_to_16_bytes; }; -/// The transposition table class. This is basically just a huge array + +/// This is the number of TTEntry slots for each position +const int ClusterSize = 5; + +/// Each group of ClusterSize number of TTEntry form a TTCluster +/// that is indexed by a single position key. Cluster is padded +/// to a cache line size so to guarantee always aligned accesses. + +struct TTCluster { + TTEntry data[ClusterSize]; + char cache_line_padding[64 - sizeof(TTEntry[ClusterSize])]; +}; + + +/// The transposition table class. This is basically just a huge array /// containing TTEntry objects, and a few methods for writing new entries /// and reading new ones. @@ -89,20 +102,20 @@ public: void prefetch(const Key posKey) const; void new_search(); void insert_pv(const Position& pos, Move pv[]); - void extract_pv(const Position& pos, Move pv[]); + void extract_pv(const Position& pos, Move pv[], const int PLY_MAX); int full() const; private: inline TTEntry* first_entry(const Key posKey) const; - // Be sure 'writes' is at least one cacheline away + // Be sure 'writes' is at least one cache line away // from read only variables. unsigned char pad_before[64 - sizeof(unsigned)]; unsigned writes; // heavy SMP read/write access here unsigned char pad_after[64]; unsigned size; - TTEntry* entries; + TTCluster* entries; uint8_t generation; };