kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-29 08:13:08 +00:00
Code Issues Releases Wiki Activity

ValueType needs only 2 bits to be stored in TT

Browse source 
Also update some more TT documentation

No functional change

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Joona Kiiski 2010-07-22 16:11:08 +03:00 • committed by Marco Costalba
parent 23db43e698
commit 6aef4429fd
1 changed files with 11 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
src/tt.h
View file

@ -48,8 +48,8 @@
/// the 32 bits of the data field are so defined
///
/// bit 0-16: move
/// bit 17-19: not used
/// bit 20-22: value type
/// bit 17-20: not used
/// bit 21-22: value type
/// bit 23-31: generation
class TTEntry {
@ -58,7 +58,7 @@ public:
void save(uint32_t k, Value v, ValueType t, Depth d, Move m, int g, Value statV, Value kd) {
key32 = k;
data = (m & 0x1FFFF) | (t << 20) | (g << 23);
data = (m & 0x1FFFF) | (t << 21) | (g << 23);
value16 = int16_t(v);
depth16 = int16_t(d);
staticValue = int16_t(statV);
@ -69,7 +69,7 @@ public:
Depth depth() const { return Depth(depth16); }
Move move() const { return Move(data & 0x1FFFF); }
Value value() const { return Value(value16); }
ValueType type() const { return ValueType((data >> 20) & 7); }
ValueType type() const { return ValueType((data >> 21) & 3); }
int generation() const { return data >> 23; }
Value static_value() const { return Value(staticValue); }
Value king_danger() const { return Value(kingDanger); }
@ -84,13 +84,12 @@ private:
};
/// This is the number of TTEntry slots for each position
/// This is the number of TTEntry slots for each cluster
const int ClusterSize = 4;
/// Each group of ClusterSize number of TTEntry form a TTCluster
/// that is indexed by a single position key. TTCluster size must
/// be not bigger then a cache line size, in case it is less then
/// it should be padded to guarantee always aligned accesses.
/// TTCluster consists of ClusterSize number of TTEntries.
/// Size of TTCluster must not be bigger than a cache line size.
/// In case it is less, it should be padded to guarantee always aligned accesses.
struct TTCluster {
TTEntry data[ClusterSize];
@ -98,7 +97,7 @@ struct TTCluster {
/// The transposition table class. This is basically just a huge array
/// containing TTEntry objects, and a few methods for writing new entries
/// containing TTCluster objects, and a few methods for writing new entries
/// and reading new ones.
class TranspositionTable {
@ -123,8 +122,8 @@ extern TranspositionTable TT;
/// TranspositionTable::first_entry returns a pointer to the first
/// entry of a cluster given a position. The low 32 bits of the key
/// are used to get the index in the table.
/// entry of a cluster given a position. The lowest order bits of the key
/// are used to get the index of the cluster.
inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {