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Use calloc() in TranspositionTable::set_size()

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Function calloc() already initializes memory to
zero, so avoid calling clear() afterwards.

Also some renaming while there (inspired by DiscoCheck).

No functional change.
This commit is contained in:
Marco Costalba
2013-06-29 10:23:43 +02:00
parent 17d41b3861
commit 203fdc9ac1
3 changed files with 42 additions and 44 deletions
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49
src/tt.cpp
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@@ -41,7 +41,7 @@ void TranspositionTable::set_size(size_t mbSize) {
hashMask = size - ClusterSize;
free(mem);
mem = malloc(size * sizeof(TTEntry) + CACHE_LINE_SIZE - 1);
mem = calloc(size * sizeof(TTEntry) + CACHE_LINE_SIZE - 1, 1);
if (!mem)
{
@@ -51,7 +51,6 @@ void TranspositionTable::set_size(size_t mbSize) {
}
table = (TTEntry*)((uintptr_t(mem) + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1));
clear(); // Operator new is not guaranteed to initialize memory to zero
}
@@ -65,6 +64,23 @@ void TranspositionTable::clear() {
}
/// 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;
}
/// TranspositionTable::store() writes a new entry containing position key and
/// valuable information of current position. The lowest order bits of position
/// key are used to decide on which cluster the position will be placed.
@@ -85,38 +101,21 @@ void TranspositionTable::store(const Key key, Value v, Bound t, Depth d, Move m,
{
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;
}