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Implement futility margins matrix 

No functinal change

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
sf_2.3.1_base
Joona Kiiski 2010-02-07 09:40:14 +02:00 committed by Marco Costalba
parent 2e70a2873f
commit 4bfa0c429e
1 changed files with 22 additions and 44 deletions
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66
src/search.cpp
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@ -126,9 +126,6 @@ namespace {
// Search depth at iteration 1
const Depth InitialDepth = OnePly;
// Depth limit for selective search
const Depth SelectiveDepth = 7 * OnePly;
// Use internal iterative deepening?
const bool UseIIDAtPVNodes = true;
const bool UseIIDAtNonPVNodes = true;
@ -150,15 +147,6 @@ namespace {
// remaining ones we will extend it.
const Value SingleReplyMargin = Value(0x20);
// Margins for futility pruning in the quiescence search, and at frontier
// and near frontier nodes.
const Value FutilityMarginQS = Value(0x80);
Value FutilityMargins[2 * PLY_MAX_PLUS_2]; // Initialized at startup.
// Each move futility margin is decreased
const Value IncrementalFutilityMargin = Value(0x8);
// Depth limit for razoring
const Depth RazorDepth = 4 * OnePly;
@ -207,6 +195,12 @@ namespace {
bool UseLogFile;
std::ofstream LogFile;
// Futility lookup tables and their getter functions
const Value FutilityMarginQS = Value(0x80);
int32_t FutilityMarginsMatrix[14][64]; // [depth][moveNumber]
inline Value futility_margin(Depth d, int mn) { return (Value) (d < 14? FutilityMarginsMatrix[Max(d, 0)][Min(mn, 63)] : 2*VALUE_INFINITE); }
// Reduction lookup tables and their getter functions
// Initialized at startup
int8_t PVReductionMatrix[64][64]; // [depth][moveNumber]
@ -554,12 +548,11 @@ void init_threads() {
}
// Init futility margins array
FutilityMargins[0] = FutilityMargins[1] = Value(0);
for (i = 2; i < 2 * PLY_MAX_PLUS_2; i++)
{
FutilityMargins[i] = Value(112 * bitScanReverse32(i * i / 2)); // FIXME: test using log instead of BSR
}
for (i = 0; i < 14; i++) // i == depth (OnePly = 2)
for (int j = 0; j < 64; j++) // j == moveNumber
{
FutilityMarginsMatrix[i][j] = (i < 2 ? 0 : 112 * bitScanReverse32(i * i / 2)) - 8 * j; // FIXME: test using log instead of BSR
}
for (i = 0; i < THREAD_MAX; i++)
Threads[i].activeSplitPoints = 0;
@ -1389,7 +1382,7 @@ namespace {
}
ss[ply].eval = staticValue;
futilityValue = staticValue + FutilityMargins[int(depth)]; //FIXME: Remove me, only for split
futilityValue = staticValue + futility_margin(depth, 0); //FIXME: Remove me, only for split
staticValue = refine_eval(tte, staticValue, ply); // Enhance accuracy with TT value if possible
update_gains(pos, ss[ply - 1].currentMove, ss[ply - 1].eval, ss[ply].eval);
}
@ -1400,8 +1393,8 @@ namespace {
if ( !isCheck
&& allowNullmove
&& depth < RazorDepth
&& staticValue - FutilityMargins[int(depth)] >= beta)
return staticValue - FutilityMargins[int(depth)];
&& staticValue - futility_margin(depth, 0) >= beta)
return staticValue - futility_margin(depth, 0);
// Null move search
if ( allowNullmove
@ -1539,29 +1532,14 @@ namespace {
continue;
// Value based pruning
Depth predictedDepth = newDepth;
Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); //FIXME: We are ignoring condition: depth >= 3*OnePly, BUG??
futilityValueScaled = ss[ply].eval + futility_margin(predictedDepth, moveCount) + H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;
//FIXME: We are ignoring condition: depth >= 3*OnePly, BUG??
ss[ply].reduction = nonpv_reduction(depth, moveCount);
if (ss[ply].reduction)
predictedDepth -= ss[ply].reduction;
if (predictedDepth < SelectiveDepth)
if (futilityValueScaled < beta)
{
int preFutilityValueMargin = 0;
if (predictedDepth >= OnePly)
preFutilityValueMargin = FutilityMargins[int(predictedDepth)];
preFutilityValueMargin += H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;
futilityValueScaled = ss[ply].eval + preFutilityValueMargin - moveCount * IncrementalFutilityMargin;
if (futilityValueScaled < beta)
{
if (futilityValueScaled > bestValue)
bestValue = futilityValueScaled;
continue;
}
if (futilityValueScaled > bestValue)
bestValue = futilityValueScaled;
continue;
}
}
@ -1860,7 +1838,7 @@ namespace {
Move move;
int moveCount;
bool isCheck = pos.is_check();
bool useFutilityPruning = sp->depth < SelectiveDepth
bool useFutilityPruning = sp->depth < 7 * OnePly //FIXME: sync with search
&& !isCheck;
const int FutilityMoveCountMargin = 3 + (1 << (3 * int(sp->depth) / 8));
@ -1897,7 +1875,7 @@ namespace {
continue;
// Value based pruning
Value futilityValueScaled = sp->futilityValue - moveCount * IncrementalFutilityMargin;
Value futilityValueScaled = sp->futilityValue - moveCount * 8; //FIXME: sync with search
if (futilityValueScaled < sp->beta)
{