mirror of
https://github.com/sockspls/badfish
synced 2025-05-02 01:29:36 +00:00
Merge Joona's new aspiration window search
It seems very positive. After 999 games at 1'+0" result is: +249 -216 =534 +11 ELO And after another 456 games we still have: +122 -113 =221
This commit is contained in:
commit
4634be8ba6
1 changed files with 118 additions and 33 deletions
149
src/search.cpp
149
src/search.cpp
|
@ -47,6 +47,26 @@ namespace {
|
||||||
|
|
||||||
/// Types
|
/// Types
|
||||||
|
|
||||||
|
// IterationInfoType stores search results for each iteration
|
||||||
|
//
|
||||||
|
// Because we use relatively small (dynamic) aspiration window,
|
||||||
|
// there happens many fail highs and fail lows in root. And
|
||||||
|
// because we don't do researches in those cases, "value" stored
|
||||||
|
// here is not necessarily exact. Instead in case of fail high/low
|
||||||
|
// we guess what the right value might be and store our guess
|
||||||
|
// as a "speculated value" and then move on. Speculated values are
|
||||||
|
// used just to calculate aspiration window width, so also if are
|
||||||
|
// not exact is not big a problem.
|
||||||
|
|
||||||
|
struct IterationInfoType {
|
||||||
|
|
||||||
|
IterationInfoType(Value v = Value(0), Value sv = Value(0))
|
||||||
|
: value(v), speculatedValue(sv) {}
|
||||||
|
|
||||||
|
Value value, speculatedValue;
|
||||||
|
};
|
||||||
|
|
||||||
|
|
||||||
// The BetaCounterType class is used to order moves at ply one.
|
// The BetaCounterType class is used to order moves at ply one.
|
||||||
// Apart for the first one that has its score, following moves
|
// Apart for the first one that has its score, following moves
|
||||||
// normally have score -VALUE_INFINITE, so are ordered according
|
// normally have score -VALUE_INFINITE, so are ordered according
|
||||||
|
@ -196,7 +216,7 @@ namespace {
|
||||||
BetaCounterType BetaCounter;
|
BetaCounterType BetaCounter;
|
||||||
|
|
||||||
// Scores and number of times the best move changed for each iteration:
|
// Scores and number of times the best move changed for each iteration:
|
||||||
Value ValueByIteration[PLY_MAX_PLUS_2];
|
IterationInfoType IterationInfo[PLY_MAX_PLUS_2];
|
||||||
int BestMoveChangesByIteration[PLY_MAX_PLUS_2];
|
int BestMoveChangesByIteration[PLY_MAX_PLUS_2];
|
||||||
|
|
||||||
// MultiPV mode
|
// MultiPV mode
|
||||||
|
@ -214,6 +234,7 @@ namespace {
|
||||||
bool AbortSearch;
|
bool AbortSearch;
|
||||||
bool Quit;
|
bool Quit;
|
||||||
bool FailHigh;
|
bool FailHigh;
|
||||||
|
bool FailLow;
|
||||||
bool Problem;
|
bool Problem;
|
||||||
bool PonderingEnabled;
|
bool PonderingEnabled;
|
||||||
int ExactMaxTime;
|
int ExactMaxTime;
|
||||||
|
@ -246,13 +267,10 @@ namespace {
|
||||||
/// Functions
|
/// Functions
|
||||||
|
|
||||||
Value id_loop(const Position &pos, Move searchMoves[]);
|
Value id_loop(const Position &pos, Move searchMoves[]);
|
||||||
Value root_search(Position &pos, SearchStack ss[], RootMoveList &rml);
|
Value root_search(Position &pos, SearchStack ss[], RootMoveList &rml, Value alpha, Value beta);
|
||||||
Value search_pv(Position &pos, SearchStack ss[], Value alpha, Value beta,
|
Value search_pv(Position &pos, SearchStack ss[], Value alpha, Value beta, Depth depth, int ply, int threadID);
|
||||||
Depth depth, int ply, int threadID);
|
Value search(Position &pos, SearchStack ss[], Value beta, Depth depth, int ply, bool allowNullmove, int threadID);
|
||||||
Value search(Position &pos, SearchStack ss[], Value beta,
|
Value qsearch(Position &pos, SearchStack ss[], Value alpha, Value beta, Depth depth, int ply, int threadID);
|
||||||
Depth depth, int ply, bool allowNullmove, int threadID);
|
|
||||||
Value qsearch(Position &pos, SearchStack ss[], Value alpha, Value beta,
|
|
||||||
Depth depth, int ply, int threadID);
|
|
||||||
void sp_search(SplitPoint *sp, int threadID);
|
void sp_search(SplitPoint *sp, int threadID);
|
||||||
void sp_search_pv(SplitPoint *sp, int threadID);
|
void sp_search_pv(SplitPoint *sp, int threadID);
|
||||||
void init_node(SearchStack ss[], int ply, int threadID);
|
void init_node(SearchStack ss[], int ply, int threadID);
|
||||||
|
@ -380,6 +398,7 @@ void think(const Position &pos, bool infinite, bool ponder, int side_to_move,
|
||||||
AbortSearch = false;
|
AbortSearch = false;
|
||||||
Quit = false;
|
Quit = false;
|
||||||
FailHigh = false;
|
FailHigh = false;
|
||||||
|
FailLow = false;
|
||||||
Problem = false;
|
Problem = false;
|
||||||
ExactMaxTime = maxTime;
|
ExactMaxTime = maxTime;
|
||||||
|
|
||||||
|
@ -654,14 +673,13 @@ namespace {
|
||||||
ss[i].init(i);
|
ss[i].init(i);
|
||||||
ss[i].initKillers();
|
ss[i].initKillers();
|
||||||
}
|
}
|
||||||
ValueByIteration[0] = Value(0);
|
IterationInfo[1] = IterationInfoType(rml.get_move_score(0), rml.get_move_score(0));
|
||||||
ValueByIteration[1] = rml.get_move_score(0);
|
|
||||||
Iteration = 1;
|
Iteration = 1;
|
||||||
|
|
||||||
EasyMove = rml.scan_for_easy_move();
|
EasyMove = rml.scan_for_easy_move();
|
||||||
|
|
||||||
// Iterative deepening loop
|
// Iterative deepening loop
|
||||||
while (!AbortSearch && Iteration < PLY_MAX)
|
while (Iteration < PLY_MAX)
|
||||||
{
|
{
|
||||||
// Initialize iteration
|
// Initialize iteration
|
||||||
rml.sort();
|
rml.sort();
|
||||||
|
@ -672,8 +690,62 @@ namespace {
|
||||||
|
|
||||||
std::cout << "info depth " << Iteration << std::endl;
|
std::cout << "info depth " << Iteration << std::endl;
|
||||||
|
|
||||||
|
// Calculate dynamic search window based on previous iterations
|
||||||
|
Value alpha, beta;
|
||||||
|
|
||||||
|
if (MultiPV == 1 && Iteration >= 6)
|
||||||
|
{
|
||||||
|
int prevDelta1 = IterationInfo[Iteration - 1].speculatedValue - IterationInfo[Iteration - 2].speculatedValue;
|
||||||
|
int prevDelta2 = IterationInfo[Iteration - 2].speculatedValue - IterationInfo[Iteration - 3].speculatedValue;
|
||||||
|
|
||||||
|
int delta = Max(2 * abs(prevDelta1) + abs(prevDelta2), ProblemMargin);
|
||||||
|
|
||||||
|
alpha = Max(IterationInfo[Iteration - 1].value - delta, -VALUE_INFINITE);
|
||||||
|
beta = Min(IterationInfo[Iteration - 1].value + delta, VALUE_INFINITE);
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
alpha = - VALUE_INFINITE;
|
||||||
|
beta = VALUE_INFINITE;
|
||||||
|
}
|
||||||
|
|
||||||
// Search to the current depth
|
// Search to the current depth
|
||||||
ValueByIteration[Iteration] = root_search(p, ss, rml);
|
Value value = root_search(p, ss, rml, alpha, beta);
|
||||||
|
|
||||||
|
// Write PV to transposition table, in case the relevant entries have
|
||||||
|
// been overwritten during the search.
|
||||||
|
TT.insert_pv(p, ss[0].pv);
|
||||||
|
|
||||||
|
if (AbortSearch)
|
||||||
|
break; // Value cannot be trusted. Break out immediately!
|
||||||
|
|
||||||
|
//Save info about search result
|
||||||
|
Value speculatedValue;
|
||||||
|
bool fHigh = false;
|
||||||
|
bool fLow = false;
|
||||||
|
Value delta = value - IterationInfo[Iteration - 1].value;
|
||||||
|
|
||||||
|
if (value >= beta)
|
||||||
|
{
|
||||||
|
assert(delta > 0);
|
||||||
|
|
||||||
|
fHigh = true;
|
||||||
|
speculatedValue = value + delta;
|
||||||
|
BestMoveChangesByIteration[Iteration] += 2; // Allocate more time
|
||||||
|
}
|
||||||
|
else if (value <= alpha)
|
||||||
|
{
|
||||||
|
assert(value == alpha);
|
||||||
|
assert(delta < 0);
|
||||||
|
|
||||||
|
fLow = true;
|
||||||
|
speculatedValue = value + delta;
|
||||||
|
BestMoveChangesByIteration[Iteration] += 3; // Allocate more time
|
||||||
|
} else
|
||||||
|
speculatedValue = value;
|
||||||
|
|
||||||
|
speculatedValue = Min(Max(speculatedValue, -VALUE_INFINITE), VALUE_INFINITE);
|
||||||
|
IterationInfo[Iteration] = IterationInfoType(value, speculatedValue);
|
||||||
|
|
||||||
// Erase the easy move if it differs from the new best move
|
// Erase the easy move if it differs from the new best move
|
||||||
if (ss[0].pv[0] != EasyMove)
|
if (ss[0].pv[0] != EasyMove)
|
||||||
|
@ -692,13 +764,15 @@ namespace {
|
||||||
|
|
||||||
// Stop search early when the last two iterations returned a mate score
|
// Stop search early when the last two iterations returned a mate score
|
||||||
if ( Iteration >= 6
|
if ( Iteration >= 6
|
||||||
&& abs(ValueByIteration[Iteration]) >= abs(VALUE_MATE) - 100
|
&& abs(IterationInfo[Iteration].value) >= abs(VALUE_MATE) - 100
|
||||||
&& abs(ValueByIteration[Iteration-1]) >= abs(VALUE_MATE) - 100)
|
&& abs(IterationInfo[Iteration-1].value) >= abs(VALUE_MATE) - 100)
|
||||||
stopSearch = true;
|
stopSearch = true;
|
||||||
|
|
||||||
// Stop search early if one move seems to be much better than the rest
|
// Stop search early if one move seems to be much better than the rest
|
||||||
int64_t nodes = nodes_searched();
|
int64_t nodes = nodes_searched();
|
||||||
if ( Iteration >= 8
|
if ( Iteration >= 8
|
||||||
|
&& !fLow
|
||||||
|
&& !fHigh
|
||||||
&& EasyMove == ss[0].pv[0]
|
&& EasyMove == ss[0].pv[0]
|
||||||
&& ( ( rml.get_move_cumulative_nodes(0) > (nodes * 85) / 100
|
&& ( ( rml.get_move_cumulative_nodes(0) > (nodes * 85) / 100
|
||||||
&& current_search_time() > MaxSearchTime / 16)
|
&& current_search_time() > MaxSearchTime / 16)
|
||||||
|
@ -719,15 +793,13 @@ namespace {
|
||||||
|
|
||||||
if (stopSearch)
|
if (stopSearch)
|
||||||
{
|
{
|
||||||
|
//FIXME: Implement fail-low emergency measures
|
||||||
if (!PonderSearch)
|
if (!PonderSearch)
|
||||||
break;
|
break;
|
||||||
else
|
else
|
||||||
StopOnPonderhit = true;
|
StopOnPonderhit = true;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
// Write PV to transposition table, in case the relevant entries have
|
|
||||||
// been overwritten during the search:
|
|
||||||
TT.insert_pv(p, ss[0].pv);
|
|
||||||
|
|
||||||
if (MaxDepth && Iteration >= MaxDepth)
|
if (MaxDepth && Iteration >= MaxDepth)
|
||||||
break;
|
break;
|
||||||
|
@ -784,15 +856,23 @@ namespace {
|
||||||
// scheme (perhaps we should try to use this at internal PV nodes, too?)
|
// scheme (perhaps we should try to use this at internal PV nodes, too?)
|
||||||
// and prints some information to the standard output.
|
// and prints some information to the standard output.
|
||||||
|
|
||||||
Value root_search(Position &pos, SearchStack ss[], RootMoveList &rml) {
|
Value root_search(Position &pos, SearchStack ss[], RootMoveList &rml, Value alpha, Value beta) {
|
||||||
|
|
||||||
Value alpha = -VALUE_INFINITE;
|
Value oldAlpha = alpha;
|
||||||
Value beta = VALUE_INFINITE, value;
|
Value value;
|
||||||
Bitboard dcCandidates = pos.discovered_check_candidates(pos.side_to_move());
|
Bitboard dcCandidates = pos.discovered_check_candidates(pos.side_to_move());
|
||||||
|
|
||||||
// Loop through all the moves in the root move list
|
// Loop through all the moves in the root move list
|
||||||
for (int i = 0; i < rml.move_count() && !AbortSearch; i++)
|
for (int i = 0; i < rml.move_count() && !AbortSearch; i++)
|
||||||
{
|
{
|
||||||
|
if (alpha >= beta)
|
||||||
|
{
|
||||||
|
// We failed high, invalidate and skip next moves, leave node-counters
|
||||||
|
// and beta-counters as they are and quickly return, we will try to do
|
||||||
|
// a research at the next iteration with a bigger aspiration window.
|
||||||
|
rml.set_move_score(i, -VALUE_INFINITE);
|
||||||
|
continue;
|
||||||
|
}
|
||||||
int64_t nodes;
|
int64_t nodes;
|
||||||
Move move;
|
Move move;
|
||||||
StateInfo st;
|
StateInfo st;
|
||||||
|
@ -825,12 +905,12 @@ namespace {
|
||||||
|
|
||||||
if (i < MultiPV)
|
if (i < MultiPV)
|
||||||
{
|
{
|
||||||
value = -search_pv(pos, ss, -beta, VALUE_INFINITE, newDepth, 1, 0);
|
value = -search_pv(pos, ss, -beta, -alpha, newDepth, 1, 0);
|
||||||
// If the value has dropped a lot compared to the last iteration,
|
// If the value has dropped a lot compared to the last iteration,
|
||||||
// set the boolean variable Problem to true. This variable is used
|
// set the boolean variable Problem to true. This variable is used
|
||||||
// for time managment: When Problem is true, we try to complete the
|
// for time managment: When Problem is true, we try to complete the
|
||||||
// current iteration before playing a move.
|
// current iteration before playing a move.
|
||||||
Problem = (Iteration >= 2 && value <= ValueByIteration[Iteration-1] - ProblemMargin);
|
Problem = (Iteration >= 2 && value <= IterationInfo[Iteration-1].value - ProblemMargin);
|
||||||
|
|
||||||
if (Problem && StopOnPonderhit)
|
if (Problem && StopOnPonderhit)
|
||||||
StopOnPonderhit = false;
|
StopOnPonderhit = false;
|
||||||
|
@ -855,7 +935,7 @@ namespace {
|
||||||
// was aborted because the user interrupted the search or because we
|
// was aborted because the user interrupted the search or because we
|
||||||
// ran out of time. In this case, the return value of the search cannot
|
// ran out of time. In this case, the return value of the search cannot
|
||||||
// be trusted, and we break out of the loop without updating the best
|
// be trusted, and we break out of the loop without updating the best
|
||||||
// move and/or PV:
|
// move and/or PV.
|
||||||
if (AbortSearch)
|
if (AbortSearch)
|
||||||
break;
|
break;
|
||||||
|
|
||||||
|
@ -874,7 +954,7 @@ namespace {
|
||||||
rml.set_move_score(i, -VALUE_INFINITE);
|
rml.set_move_score(i, -VALUE_INFINITE);
|
||||||
else
|
else
|
||||||
{
|
{
|
||||||
// New best move!
|
// PV move or new best move!
|
||||||
|
|
||||||
// Update PV
|
// Update PV
|
||||||
rml.set_move_score(i, value);
|
rml.set_move_score(i, value);
|
||||||
|
@ -906,11 +986,12 @@ namespace {
|
||||||
LogFile << pretty_pv(pos, current_search_time(), Iteration, nodes_searched(), value, ss[0].pv)
|
LogFile << pretty_pv(pos, current_search_time(), Iteration, nodes_searched(), value, ss[0].pv)
|
||||||
<< std::endl;
|
<< std::endl;
|
||||||
|
|
||||||
|
if (value > alpha)
|
||||||
alpha = value;
|
alpha = value;
|
||||||
|
|
||||||
// Reset the global variable Problem to false if the value isn't too
|
// Reset the global variable Problem to false if the value isn't too
|
||||||
// far below the final value from the last iteration.
|
// far below the final value from the last iteration.
|
||||||
if (value > ValueByIteration[Iteration - 1] - NoProblemMargin)
|
if (value > IterationInfo[Iteration - 1].value - NoProblemMargin)
|
||||||
Problem = false;
|
Problem = false;
|
||||||
}
|
}
|
||||||
else // MultiPV > 1
|
else // MultiPV > 1
|
||||||
|
@ -934,7 +1015,11 @@ namespace {
|
||||||
}
|
}
|
||||||
alpha = rml.get_move_score(Min(i, MultiPV-1));
|
alpha = rml.get_move_score(Min(i, MultiPV-1));
|
||||||
}
|
}
|
||||||
}
|
} // New best move case
|
||||||
|
|
||||||
|
assert(alpha >= oldAlpha);
|
||||||
|
|
||||||
|
FailLow = (alpha == oldAlpha);
|
||||||
}
|
}
|
||||||
return alpha;
|
return alpha;
|
||||||
}
|
}
|
||||||
|
@ -1083,7 +1168,7 @@ namespace {
|
||||||
// (from the computer's point of view) since the previous iteration:
|
// (from the computer's point of view) since the previous iteration:
|
||||||
if ( ply == 1
|
if ( ply == 1
|
||||||
&& Iteration >= 2
|
&& Iteration >= 2
|
||||||
&& -value <= ValueByIteration[Iteration-1] - ProblemMargin)
|
&& -value <= IterationInfo[Iteration-1].value - ProblemMargin)
|
||||||
Problem = true;
|
Problem = true;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -1796,7 +1881,7 @@ namespace {
|
||||||
// (from the computer's point of view) since the previous iteration.
|
// (from the computer's point of view) since the previous iteration.
|
||||||
if ( sp->ply == 1
|
if ( sp->ply == 1
|
||||||
&& Iteration >= 2
|
&& Iteration >= 2
|
||||||
&& -value <= ValueByIteration[Iteration-1] - ProblemMargin)
|
&& -value <= IterationInfo[Iteration-1].value - ProblemMargin)
|
||||||
Problem = true;
|
Problem = true;
|
||||||
}
|
}
|
||||||
lock_release(&(sp->lock));
|
lock_release(&(sp->lock));
|
||||||
|
@ -2425,8 +2510,8 @@ namespace {
|
||||||
return;
|
return;
|
||||||
|
|
||||||
bool overTime = t > AbsoluteMaxSearchTime
|
bool overTime = t > AbsoluteMaxSearchTime
|
||||||
|| (RootMoveNumber == 1 && t > MaxSearchTime + ExtraSearchTime)
|
|| (RootMoveNumber == 1 && t > MaxSearchTime + ExtraSearchTime && !FailLow) //FIXME: We are not checking any problem flags, BUG?
|
||||||
|| ( !FailHigh && !fail_high_ply_1() && !Problem
|
|| ( !FailHigh && !FailLow && !fail_high_ply_1() && !Problem
|
||||||
&& t > 6*(MaxSearchTime + ExtraSearchTime));
|
&& t > 6*(MaxSearchTime + ExtraSearchTime));
|
||||||
|
|
||||||
if ( (Iteration >= 3 && (!InfiniteSearch && overTime))
|
if ( (Iteration >= 3 && (!InfiniteSearch && overTime))
|
||||||
|
@ -2447,8 +2532,8 @@ namespace {
|
||||||
(!InfiniteSearch && (StopOnPonderhit ||
|
(!InfiniteSearch && (StopOnPonderhit ||
|
||||||
t > AbsoluteMaxSearchTime ||
|
t > AbsoluteMaxSearchTime ||
|
||||||
(RootMoveNumber == 1 &&
|
(RootMoveNumber == 1 &&
|
||||||
t > MaxSearchTime + ExtraSearchTime) ||
|
t > MaxSearchTime + ExtraSearchTime && !FailLow) ||
|
||||||
(!FailHigh && !fail_high_ply_1() && !Problem &&
|
(!FailHigh && !FailLow && !fail_high_ply_1() && !Problem &&
|
||||||
t > 6*(MaxSearchTime + ExtraSearchTime)))))
|
t > 6*(MaxSearchTime + ExtraSearchTime)))))
|
||||||
AbortSearch = true;
|
AbortSearch = true;
|
||||||
}
|
}
|
||||||
|
|
Loading…
Add table
Reference in a new issue