// 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);
for (i = 0; i < THREAD_MAX; i++)
Threads[i].activeSplitPoints = 0;
+ // 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
+ }
+
// Initialize global locks
lock_init(&MPLock, NULL);
lock_init(&IOLock, NULL);
&& !captureOrPromotion
&& !move_is_castle(move))
{
- double red = 0.5 + ln(RootMoveNumber - MultiPV + 1) * ln(depth / 2) / 6.0;
- if (red >= 1.0)
+ ss[0].reduction = calculate_reduction(0.5, RootMoveNumber - MultiPV + 1, depth, 6.0);
+ if (ss[0].reduction)
{
- ss[0].reduction = Depth(int(floor(red * int(OnePly))));
value = -search(pos, ss, -alpha, newDepth-ss[0].reduction, 1, true, 0);
doFullDepthSearch = (value > alpha);
}
if (doFullDepthSearch)
{
+ ss[0].reduction = Depth(0);
value = -search(pos, ss, -alpha, newDepth, 1, true, 0);
if (value > alpha)
&& !move_is_castle(move)
&& !move_is_killer(move, ss[ply]))
{
- double red = 0.5 + ln(moveCount) * ln(depth / 2) / 6.0;
- if (red >= 1.0)
- {
- ss[ply].reduction = Depth(int(floor(red * int(OnePly))));
- value = -search(pos, ss, -alpha, newDepth-ss[ply].reduction, ply+1, true, threadID);
- doFullDepthSearch = (value > alpha);
- }
+ ss[ply].reduction = calculate_reduction(0.5, moveCount, depth, 6.0);
+ if (ss[ply].reduction)
+ {
+ value = -search(pos, ss, -alpha, newDepth-ss[ply].reduction, ply+1, true, threadID);
+ doFullDepthSearch = (value > alpha);
+ }
}
if (doFullDepthSearch) // Go with full depth non-pv search
// Calculate depth dependant futility pruning parameters
const int FutilityMoveCountMargin = 3 + (1 << (3 * int(depth) / 8));
- const int PostFutilityValueMargin = 112 * bitScanReverse32(int(depth) * int(depth) / 2);
+ const int PostFutilityValueMargin = FutilityMargins[int(depth)];
// Evaluate the position statically
if (!isCheck)
int preFutilityValueMargin = 0;
if (newDepth >= OnePly)
- preFutilityValueMargin = 112 * bitScanReverse32(int(newDepth) * int(newDepth) / 2);
+ preFutilityValueMargin = FutilityMargins[int(newDepth)];
Value futilityCaptureValue = ss[ply].eval + pos.endgame_value_of_piece_on(move_to(move)) + preFutilityValueMargin + ei.futilityMargin + 90;
// Value based pruning
Depth predictedDepth = newDepth;
- //FIXME HACK: awful code duplication
- double red = 0.5 + ln(moveCount) * ln(depth / 2) / 3.0;
- if (red >= 1.0)
- predictedDepth -= int(floor(red * int(OnePly)));
+ //FIXME: We are ignoring condition: depth >= 3*OnePly, BUG??
+ ss[ply].reduction = calculate_reduction(0.5, moveCount, depth, 3.0);
+ if (ss[ply].reduction)
+ predictedDepth -= ss[ply].reduction;
if (predictedDepth < SelectiveDepth)
{
int preFutilityValueMargin = 0;
if (predictedDepth >= OnePly)
- preFutilityValueMargin = 112 * bitScanReverse32(int(predictedDepth) * int(predictedDepth) / 2);
+ preFutilityValueMargin = FutilityMargins[int(predictedDepth)];
preFutilityValueMargin += H.gain(pos.piece_on(move_from(move)), move_from(move), move_to(move)) + 45;
&& !dangerous
&& !captureOrPromotion
&& !move_is_castle(move)
- && !move_is_killer(move, ss[ply])
- /* && move != ttMove*/)
+ && !move_is_killer(move, ss[ply]))
{
- double red = 0.5 + ln(moveCount) * ln(depth / 2) / 3.0;
- if (red >= 1.0)
+ ss[ply].reduction = calculate_reduction(0.5, moveCount, depth, 3.0);
+ if (ss[ply].reduction)
{
- ss[ply].reduction = Depth(int(floor(red * int(OnePly))));
value = -search(pos, ss, -(beta-1), newDepth-ss[ply].reduction, ply+1, true, threadID);
doFullDepthSearch = (value >= beta);
}
&& !move_is_castle(move)
&& !move_is_killer(move, ss[sp->ply]))
{
- double red = 0.5 + ln(moveCount) * ln(sp->depth / 2) / 3.0;
- if (red >= 1.0)
+ ss[sp->ply].reduction = calculate_reduction(0.5, moveCount, sp->depth, 3.0);
+ if (ss[sp->ply].reduction)
{
- ss[sp->ply].reduction = Depth(int(floor(red * int(OnePly))));
value = -search(pos, ss, -(sp->beta-1), newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID);
doFullDepthSearch = (value >= sp->beta);
}
&& !move_is_castle(move)
&& !move_is_killer(move, ss[sp->ply]))
{
- double red = 0.5 + ln(moveCount) * ln(sp->depth / 2) / 6.0;
- if (red >= 1.0)
+ ss[sp->ply].reduction = calculate_reduction(0.5, moveCount, sp->depth, 6.0);
+ if (ss[sp->ply].reduction)
{
Value localAlpha = sp->alpha;
- ss[sp->ply].reduction = Depth(int(floor(red * int(OnePly))));
value = -search(pos, ss, -localAlpha, newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID);
doFullDepthSearch = (value > localAlpha);
}