/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
- Copyright (C) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
TranspositionTable TT; // Our global transposition table
-/// TTEntry::save populates the TTEntry with a new node's data, possibly
+/// TTEntry::save() populates the TTEntry with a new node's data, possibly
/// overwriting an old position. Update is not atomic and can be racy.
void TTEntry::save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev) {
// Preserve any existing move for the same position
- if (m || (k >> 48) != key16)
+ if (m || (uint16_t)k != key16)
move16 = (uint16_t)m;
- // Overwrite less valuable entries
- if ( (k >> 48) != key16
- || d - DEPTH_OFFSET > depth8 - 4
- || b == BOUND_EXACT)
+ // Overwrite less valuable entries (cheapest checks first)
+ if (b == BOUND_EXACT
+ || (uint16_t)k != key16
+ || d - DEPTH_OFFSET > depth8 - 4)
{
- assert(d >= DEPTH_OFFSET);
+ assert(d > DEPTH_OFFSET);
+ assert(d < 256 + DEPTH_OFFSET);
- key16 = (uint16_t)(k >> 48);
+ key16 = (uint16_t)k;
+ depth8 = (uint8_t)(d - DEPTH_OFFSET);
+ genBound8 = (uint8_t)(TT.generation8 | uint8_t(pv) << 2 | b);
value16 = (int16_t)v;
eval16 = (int16_t)ev;
- genBound8 = (uint8_t)(TT.generation8 | uint8_t(pv) << 2 | b);
- depth8 = (uint8_t)(d - DEPTH_OFFSET);
}
}
Threads.main()->wait_for_search_finished();
- if (mem)
- aligned_ttmem_free(mem);
-
- if (!mbSize)
- {
- mem = nullptr;
- return;
- }
+ aligned_large_pages_free(table);
clusterCount = mbSize * 1024 * 1024 / sizeof(Cluster);
- table = static_cast<Cluster*>(aligned_ttmem_alloc(clusterCount * sizeof(Cluster), mem));
- if (!mem)
+
+ table = static_cast<Cluster*>(aligned_large_pages_alloc(clusterCount * sizeof(Cluster)));
+ if (!table)
{
std::cerr << "Failed to allocate " << mbSize
<< "MB for transposition table." << std::endl;
WinProcGroup::bindThisThread(idx);
// Each thread will zero its part of the hash table
- const size_t stride = clusterCount / Options["Threads"],
- start = stride * idx,
+ const size_t stride = size_t(clusterCount / Options["Threads"]),
+ start = size_t(stride * idx),
len = idx != Options["Threads"] - 1 ?
stride : clusterCount - start;
});
}
- for (std::thread& th: threads)
+ for (std::thread& th : threads)
th.join();
}
+
/// TranspositionTable::probe() looks up the current position in the transposition
/// table. It returns true and a pointer to the TTEntry if the position is found.
/// Otherwise, it returns false and a pointer to an empty or least valuable TTEntry
TTEntry* TranspositionTable::probe(const Key key, bool& found) const {
TTEntry* const tte = first_entry(key);
- const uint16_t key16 = key >> 48; // Use the high 16 bits as key inside the cluster
+ const uint16_t key16 = (uint16_t)key; // Use the low 16 bits as key inside the cluster
for (int i = 0; i < ClusterSize; ++i)
- if (!tte[i].key16 || tte[i].key16 == key16)
+ if (tte[i].key16 == key16 || !tte[i].depth8)
{
tte[i].genBound8 = uint8_t(generation8 | (tte[i].genBound8 & 0x7)); // Refresh
- return found = (bool)tte[i].key16, &tte[i];
+ return found = (bool)tte[i].depth8, &tte[i];
}
// Find an entry to be replaced according to the replacement strategy
int cnt = 0;
for (int i = 0; i < 1000; ++i)
for (int j = 0; j < ClusterSize; ++j)
- cnt += (table[i].entry[j].genBound8 & 0xF8) == generation8;
+ cnt += table[i].entry[j].depth8 && (table[i].entry[j].genBound8 & 0xF8) == generation8;
return cnt / ClusterSize;
}