/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
assert(msb((mbSize << 20) / sizeof(TTEntry)) < 32);
- uint32_t size = 1 << msb((mbSize << 20) / sizeof(TTEntry[ClusterSize]));
+ uint32_t size = ClusterSize << msb((mbSize << 20) / sizeof(TTEntry[ClusterSize]));
- if (clusterMask == size - 1)
+ if (hashMask == size - ClusterSize)
return;
- clusterMask = size - 1;
- delete [] entries;
- entries = new (std::nothrow) TTEntry[size * ClusterSize];
+ hashMask = size - ClusterSize;
+ free(mem);
+ mem = calloc(size * sizeof(TTEntry) + CACHE_LINE_SIZE - 1, 1);
- if (!entries)
+ if (!mem)
{
std::cerr << "Failed to allocate " << mbSize
<< "MB for transposition table." << std::endl;
exit(EXIT_FAILURE);
}
- clear(); // Operator new is not guaranteed to initialize memory to zero
+ table = (TTEntry*)((uintptr_t(mem) + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1));
}
void TranspositionTable::clear() {
- memset(entries, 0, (clusterMask + 1) * sizeof(TTEntry[ClusterSize]));
+ std::memset(table, 0, (hashMask + ClusterSize) * sizeof(TTEntry));
+}
+
+
+/// TranspositionTable::probe() looks up the current position in the
+/// transposition table. Returns a pointer to the TTEntry or NULL if
+/// position is not found.
+
+const TTEntry* TranspositionTable::probe(const Key key) const {
+
+ const TTEntry* tte = first_entry(key);
+ uint32_t key32 = key >> 32;
+
+ for (unsigned i = 0; i < ClusterSize; i++, tte++)
+ if (tte->key() == key32)
+ return tte;
+
+ return NULL;
}
{
if (!tte->key() || tte->key() == key32) // Empty or overwrite old
{
- // Preserve any existing ttMove
- if (m == MOVE_NONE)
- m = tte->move();
+ if (!m)
+ m = tte->move(); // Preserve any existing ttMove
- tte->save(key32, v, t, d, m, generation, statV, kingD);
- return;
+ replace = tte;
+ break;
}
// Implement replace strategy
c1 = (replace->generation() == generation ? 2 : 0);
- c2 = (tte->generation() == generation || tte->type() == BOUND_EXACT ? -2 : 0);
+ c2 = (tte->generation() == generation || tte->bound() == BOUND_EXACT ? -2 : 0);
c3 = (tte->depth() < replace->depth() ? 1 : 0);
if (c1 + c2 + c3 > 0)
replace = tte;
}
- replace->save(key32, v, t, d, m, generation, statV, kingD);
-}
-
-
-/// TranspositionTable::probe() looks up the current position in the
-/// transposition table. Returns a pointer to the TTEntry or NULL if
-/// position is not found.
-
-TTEntry* TranspositionTable::probe(const Key key) const {
- TTEntry* tte = first_entry(key);
- uint32_t key32 = key >> 32;
-
- for (unsigned i = 0; i < ClusterSize; i++, tte++)
- if (tte->key() == key32)
- return tte;
-
- return NULL;
+ replace->save(key32, v, t, d, m, generation, statV, kingD);
}