kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-07-11 19:49:14 +00:00
Code Issues Releases Wiki Activity

Sync qsearch with search

Browse source 
So to have the same layout and be as much similar as
possible. The only functional change is that now we
try ttMove as first also in PV nodes and at the end
we save the ttMove, as it happens in search. This
should have almost zero impact on ELO but it seems
the correct thing to do.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba 2010-01-08 11:45:46 +01:00
parent dba072c449
commit 5b21c10afb
1 changed files with 42 additions and 48 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

74
src/search.cpp
View file

@ -1400,7 +1400,7 @@ namespace {
const int FutilityMoveCountMargin = 3 + (1 << (3 * int(depth) / 8));
const int FutilityValueMargin = 112 * bitScanReverse32(int(depth) * int(depth) / 2);
// Enhance position with TT value if possible
// Enhance score accuracy with TT value if possible
futilityValue = staticValue + FutilityValueMargin;
staticValue = refine_eval(tte, staticValue, ply);
@ -1492,8 +1492,8 @@ namespace {
if (move == excludedMove)
continue;
singleEvasion = (isCheck && mp.number_of_evasions() == 1);
moveIsCheck = pos.move_is_check(move, ci);
singleEvasion = (isCheck && mp.number_of_evasions() == 1);
captureOrPromotion = pos.move_is_capture_or_promotion(move);
// Decide the new search depth
@ -1608,7 +1608,7 @@ namespace {
// All legal moves have been searched. A special case: If there were
// no legal moves, it must be mate or stalemate.
if (moveCount == 0)
if (!moveCount)
return excludedMove ? beta - 1 : (pos.is_check() ? value_mated_in(ply) : VALUE_DRAW);
// If the search is not aborted, update the transposition table,
@ -1622,12 +1622,13 @@ namespace {
{
BetaCounter.add(pos.side_to_move(), depth, threadID);
move = ss[ply].pv[ply];
TT.store(posKey, value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, move);
if (!pos.move_is_capture_or_promotion(move))
{
update_history(pos, move, depth, movesSearched, moveCount);
update_killers(move, ss[ply]);
}
TT.store(posKey, value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, depth, move);
}
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
@ -1652,7 +1653,7 @@ namespace {
EvalInfo ei;
StateInfo st;
Move ttMove, move;
Value staticValue, bestValue, value, futilityValue;
Value staticValue, bestValue, value, futilityBase, futilityValue;
bool isCheck, enoughMaterial, moveIsCheck;
const TTEntry* tte = NULL;
int moveCount = 0;
@ -1669,18 +1670,21 @@ namespace {
if (pos.is_draw())
return VALUE_DRAW;
// Transposition table lookup, only when not in PV
if (!pvNode)
{
if (ply >= PLY_MAX - 1)
return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID);
// Transposition table lookup. At PV nodes, we don't use the TT for
// pruning, but only for move ordering.
tte = TT.retrieve(pos.get_key());
if (tte && ok_to_use_TT(tte, depth, beta, ply))
ttMove = (tte ? tte->move() : MOVE_NONE);
if (!pvNode && tte && ok_to_use_TT(tte, depth, beta, ply))
{
assert(tte->type() != VALUE_TYPE_EVAL);
ss[ply].currentMove = ttMove; // Can be MOVE_NONE
return value_from_tt(tte->value(), ply);
}
}
ttMove = (tte ? tte->move() : MOVE_NONE);
isCheck = pos.is_check();
ei.futilityMargin = Value(0); // Manually initialize futilityMargin
@ -1688,20 +1692,11 @@ namespace {
// Evaluate the position statically
if (isCheck)
staticValue = -VALUE_INFINITE;
else if (tte && (tte->type() & VALUE_TYPE_EVAL))
{
// Use the cached evaluation score if possible
assert(ei.futilityMargin == Value(0));
staticValue = value_from_tt(tte->value(), ply);
}
else
staticValue = evaluate(pos, ei, threadID);
if (ply >= PLY_MAX - 1)
return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID);
// Initialize "stand pat score", and return it immediately if it is
// at least beta.
bestValue = staticValue;
@ -1724,6 +1719,7 @@ namespace {
MovePicker mp = MovePicker(pos, ttMove, depth, H);
CheckInfo ci(pos);
enoughMaterial = pos.non_pawn_material(pos.side_to_move()) > RookValueMidgame;
futilityBase = staticValue + FutilityMarginQS + ei.futilityMargin;
// Loop through the moves until no moves remain or a beta cutoff
// occurs.
@ -1732,11 +1728,12 @@ namespace {
{
assert(move_is_ok(move));
moveIsCheck = pos.move_is_check(move, ci);
// Update current move
moveCount++;
ss[ply].currentMove = move;
moveIsCheck = pos.move_is_check(move, ci);
// Futility pruning
if ( enoughMaterial
&& !isCheck
@ -1746,12 +1743,9 @@ namespace {
&& !move_is_promotion(move)
&& !pos.move_is_passed_pawn_push(move))
{
futilityValue = staticValue
+ Max(pos.midgame_value_of_piece_on(move_to(move)),
pos.endgame_value_of_piece_on(move_to(move)))
+ (move_is_ep(move) ? PawnValueEndgame : Value(0))
+ FutilityMarginQS
+ ei.futilityMargin;
futilityValue = futilityBase
+ pos.endgame_value_of_piece_on(move_to(move))
+ (move_is_ep(move) ? PawnValueEndgame : Value(0));
if (futilityValue < alpha)
{
@ -1792,26 +1786,26 @@ namespace {
if (!moveCount && pos.is_check()) // Mate!
return value_mated_in(ply);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
// Update transposition table
move = ss[ply].pv[ply];
if (!pvNode)
{
// If bestValue isn't changed it means it is still the static evaluation of
// the node, so keep this info to avoid a future costly evaluation() call.
ValueType type = (bestValue == staticValue && !ei.futilityMargin ? VALUE_TYPE_EV_UP : VALUE_TYPE_UPPER);
Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1));
if (bestValue < beta)
{
// If bestValue isn't changed it means it is still the static evaluation
// of the node, so keep this info to avoid a future evaluation() call.
ValueType type = (bestValue == staticValue && !ei.futilityMargin ? VALUE_TYPE_EV_UP : VALUE_TYPE_UPPER);
TT.store(pos.get_key(), value_to_tt(bestValue, ply), type, d, MOVE_NONE);
}
else
{
move = ss[ply].pv[ply];
TT.store(pos.get_key(), value_to_tt(bestValue, ply), VALUE_TYPE_LOWER, d, move);
// Update killers only for good checking moves
if (!pos.move_is_capture_or_promotion(move))
update_killers(move, ss[ply]);
}
// Update killers only for good check moves
if (alpha >= beta && !pos.move_is_capture_or_promotion(move))
update_killers(move, ss[ply]);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
return bestValue;
}