/// Constructor
TranspositionTable::TranspositionTable(unsigned mbSize) {
+
size = 0;
generation = 0;
writes = 0;
entries = 0;
- this->set_size(mbSize);
+ set_size(mbSize);
}
/// Destructor
TranspositionTable::~TranspositionTable() {
+
delete [] entries;
}
/// measured in megabytes.
void TranspositionTable::set_size(unsigned mbSize) {
- unsigned newSize;
assert(mbSize >= 4 && mbSize <= 1024);
- for(newSize = 1024; newSize * 4 * (sizeof(TTEntry)) <= (mbSize << 20);
- newSize *= 2);
- newSize /= 2;
+ unsigned newSize = 1024;
- if(newSize != size) {
+ // We store a cluster of 4 TTEntry for each position and newSize is
+ // the maximum number of storable positions
+ for ( ; newSize * 4 * (sizeof(TTEntry)) <= (mbSize << 20); newSize *= 2);
+ newSize /= 2;
+ if (newSize != size)
+ {
size = newSize;
delete [] entries;
entries = new TTEntry[size * 4];
- if(entries == NULL) {
+ if (!entries)
+ {
std::cerr << "Failed to allocate " << mbSize
<< " MB for transposition table."
<< std::endl;
exit(EXIT_FAILURE);
}
- this->clear();
+ clear();
}
}
/// Perhaps we should also clear it when the "ucinewgame" command is recieved?
void TranspositionTable::clear() {
+
memset(entries, 0, size * 4 * sizeof(TTEntry));
}
TTEntry *tte, *replace;
tte = replace = entries + int(pos.get_key() & (size - 1)) * 4;
- for(int i = 0; i < 4; i++) {
- if((tte+i)->key() == pos.get_key()) {
- if(m == MOVE_NONE)
- m = (tte+i)->move();
- *(tte+i) = TTEntry(pos.get_key(), v, type, d, m, generation);
- return;
+ for (int i = 0; i < 4; i++)
+ {
+ if ((tte+i)->key() == pos.get_key())
+ {
+ if (m == MOVE_NONE)
+ m = (tte+i)->move();
+
+ *(tte+i) = TTEntry(pos.get_key(), v, type, d, m, generation);
+ return;
}
- if(replace->generation() == generation) {
- if((tte+i)->generation() != generation ||
- (tte+i)->depth() < replace->depth())
- replace = tte+i;
+ if (replace->generation() == generation)
+ {
+ if ((tte+i)->generation() != generation || (tte+i)->depth() < replace->depth())
+ replace = tte+i;
}
- else if((tte+i)->generation() != generation &&
- (tte+i)->depth() < replace->depth())
- replace = tte+i;
+ else if ((tte+i)->generation() != generation && (tte+i)->depth() < replace->depth())
+ replace = tte+i;
}
*replace = TTEntry(pos.get_key(), v, type, d, m, generation);
writes++;
bool found = false;
tte = entries + int(pos.get_key() & (size - 1)) * 4;
- for(int i = 0; i < 4 && !found ; i++)
- if((tte+i)->key() == pos.get_key()) {
- tte = tte + i;
- found = true;
- }
- if(!found) {
- *move = MOVE_NONE;
- return false;
+ for (int i = 0; i < 4 && !found ; i++)
+ if ((tte+i)->key() == pos.get_key())
+ {
+ tte = tte + i;
+ found = true;
+ }
+ if (!found) {
+ *move = MOVE_NONE;
+ return false;
}
-
*value = tte->value();
*type = tte->type();
*d = tte->depth();
*move = tte->move();
-
return true;
}
/// entries from the current search.
void TranspositionTable::new_search() {
+
generation++;
writes = 0;
}
/// overwritten.
void TranspositionTable::insert_pv(const Position &pos, Move pv[]) {
+
UndoInfo u;
Position p(pos);
- for(int i = 0; pv[i] != MOVE_NONE; i++) {
- this->store(p, VALUE_NONE, Depth(0), pv[i], VALUE_TYPE_NONE);
+ for (int i = 0; pv[i] != MOVE_NONE; i++)
+ {
+ store(p, VALUE_NONE, Depth(0), pv[i], VALUE_TYPE_NONE);
p.do_move(pv[i], u);
}
}
/// It is used to display the "info hashfull ..." information in UCI.
int TranspositionTable::full() {
+
double N = double(size) * 4.0;
return int(1000 * (1 - exp(writes * log(1.0 - 1.0/N))));
}
/// Functions for extracting data from TTEntry objects.
-Key TTEntry::key() const {
+inline Key TTEntry::key() const {
return key_;
}
-Depth TTEntry::depth() const {
+inline Depth TTEntry::depth() const {
return Depth(depth_);
}
-Move TTEntry::move() const {
+inline Move TTEntry::move() const {
return Move(data & 0x7FFFF);
}
-Value TTEntry::value() const {
+inline Value TTEntry::value() const {
return Value(value_);
}
-ValueType TTEntry::type() const {
+inline ValueType TTEntry::type() const {
return ValueType((data >> 20) & 3);
}
-int TTEntry::generation() const {
+inline int TTEntry::generation() const {
return (data >> 23);
}