mirror of
https://github.com/sockspls/badfish
synced 2025-04-30 08:43:09 +00:00
Revert saving of null search value in TT
Revert all the patches that introduced the change and more or less fixed the zugzwang issue. There is a gain against last current version and we can remove a lot of code. After 979 games at 1+0 on my QUAD Mod vs Orig +152 =688 -139 +5 ELO Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
parent
ec0a650dff
commit
65c2715d9a
3 changed files with 39 additions and 59 deletions
|
|
@ -104,13 +104,6 @@ namespace {
|
|||
|
||||
};
|
||||
|
||||
// FIXME: document me
|
||||
|
||||
enum NullStatus {
|
||||
ALLOW_NULLMOVE,
|
||||
FORBID_NULLMOVE,
|
||||
VERIFY_NULLMOVE
|
||||
};
|
||||
|
||||
// RootMove struct is used for moves at the root at the tree. For each
|
||||
// root move, we store a score, a node count, and a PV (really a refutation
|
||||
|
|
@ -288,7 +281,7 @@ namespace {
|
|||
Value id_loop(const Position& pos, Move searchMoves[]);
|
||||
Value root_search(Position& pos, SearchStack ss[], RootMoveList& rml, Value* alphaPtr, Value* betaPtr);
|
||||
Value search_pv(Position& pos, SearchStack ss[], Value alpha, Value beta, Depth depth, int ply, int threadID);
|
||||
Value search(Position& pos, SearchStack ss[], Value beta, Depth depth, int ply, NullStatus nullStatus, int threadID, Move excludedMove = MOVE_NONE);
|
||||
Value search(Position& pos, SearchStack ss[], Value beta, Depth depth, int ply, bool allowNullmove, int threadID, Move excludedMove = MOVE_NONE);
|
||||
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_pv(SplitPoint* sp, int threadID);
|
||||
|
|
@ -301,7 +294,7 @@ namespace {
|
|||
Depth extension(const Position&, Move, bool, bool, bool, bool, bool, bool*);
|
||||
bool ok_to_do_nullmove(const Position& pos);
|
||||
bool ok_to_prune(const Position& pos, Move m, Move threat);
|
||||
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply, bool allowNullmove);
|
||||
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
|
||||
Value refine_eval(const TTEntry* tte, Value defaultEval, int ply);
|
||||
void update_history(const Position& pos, Move move, Depth depth, Move movesSearched[], int moveCount);
|
||||
void update_killers(Move m, SearchStack& ss);
|
||||
|
|
@ -893,7 +886,7 @@ namespace {
|
|||
if (ss[0].reduction)
|
||||
{
|
||||
// Reduced depth non-pv search using alpha as upperbound
|
||||
value = -search(pos, ss, -alpha, newDepth-ss[0].reduction, 1, ALLOW_NULLMOVE, 0);
|
||||
value = -search(pos, ss, -alpha, newDepth-ss[0].reduction, 1, true, 0);
|
||||
doFullDepthSearch = (value > alpha);
|
||||
}
|
||||
}
|
||||
|
|
@ -903,7 +896,7 @@ namespace {
|
|||
{
|
||||
// Full depth non-pv search using alpha as upperbound
|
||||
ss[0].reduction = Depth(0);
|
||||
value = -search(pos, ss, -alpha, newDepth, 1, ALLOW_NULLMOVE, 0);
|
||||
value = -search(pos, ss, -alpha, newDepth, 1, true, 0);
|
||||
|
||||
// If we are above alpha then research at same depth but as PV
|
||||
// to get a correct score or eventually a fail high above beta.
|
||||
|
|
@ -1138,7 +1131,7 @@ namespace {
|
|||
|
||||
if (abs(ttValue) < VALUE_KNOWN_WIN)
|
||||
{
|
||||
Value excValue = search(pos, ss, ttValue - SingularExtensionMargin, depth / 2, ply, FORBID_NULLMOVE, threadID, move);
|
||||
Value excValue = search(pos, ss, ttValue - SingularExtensionMargin, depth / 2, ply, false, threadID, move);
|
||||
|
||||
if (excValue < ttValue - SingularExtensionMargin)
|
||||
ext = OnePly;
|
||||
|
|
@ -1174,7 +1167,7 @@ namespace {
|
|||
ss[ply].reduction = pv_reduction(depth, moveCount);
|
||||
if (ss[ply].reduction)
|
||||
{
|
||||
value = -search(pos, ss, -alpha, newDepth-ss[ply].reduction, ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -alpha, newDepth-ss[ply].reduction, ply+1, true, threadID);
|
||||
doFullDepthSearch = (value > alpha);
|
||||
}
|
||||
}
|
||||
|
|
@ -1183,7 +1176,7 @@ namespace {
|
|||
if (doFullDepthSearch)
|
||||
{
|
||||
ss[ply].reduction = Depth(0);
|
||||
value = -search(pos, ss, -alpha, newDepth, ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -alpha, newDepth, ply+1, true, threadID);
|
||||
|
||||
// Step extra. pv search (only in PV nodes)
|
||||
if (value > alpha && value < beta)
|
||||
|
|
@ -1258,7 +1251,7 @@ namespace {
|
|||
// search() is the search function for zero-width nodes.
|
||||
|
||||
Value search(Position& pos, SearchStack ss[], Value beta, Depth depth,
|
||||
int ply, NullStatus nullStatus, int threadID, Move excludedMove) {
|
||||
int ply, bool allowNullmove, int threadID, Move excludedMove) {
|
||||
|
||||
assert(beta >= -VALUE_INFINITE && beta <= VALUE_INFINITE);
|
||||
assert(ply >= 0 && ply < PLY_MAX);
|
||||
|
|
@ -1306,7 +1299,7 @@ namespace {
|
|||
tte = TT.retrieve(posKey);
|
||||
ttMove = (tte ? tte->move() : MOVE_NONE);
|
||||
|
||||
if (tte && ok_to_use_TT(tte, depth, beta, ply, nullStatus != VERIFY_NULLMOVE))
|
||||
if (tte && ok_to_use_TT(tte, depth, beta, ply))
|
||||
{
|
||||
ss[ply].currentMove = ttMove; // Can be MOVE_NONE
|
||||
return value_from_tt(tte->value(), ply);
|
||||
|
|
@ -1346,7 +1339,7 @@ namespace {
|
|||
// Step 7. Static null move pruning
|
||||
// We're betting that the opponent doesn't have a move that will reduce
|
||||
// the score by more than futility_margin(depth) if we do a null move.
|
||||
if ( nullStatus == ALLOW_NULLMOVE
|
||||
if ( allowNullmove
|
||||
&& depth < RazorDepth
|
||||
&& !isCheck
|
||||
&& !value_is_mate(beta)
|
||||
|
|
@ -1358,7 +1351,7 @@ namespace {
|
|||
// When we jump directly to qsearch() we do a null move only if static value is
|
||||
// at least beta. Otherwise we do a null move if static value is not more than
|
||||
// NullMoveMargin under beta.
|
||||
if ( nullStatus == ALLOW_NULLMOVE
|
||||
if ( allowNullmove
|
||||
&& depth > OnePly
|
||||
&& !isCheck
|
||||
&& !value_is_mate(beta)
|
||||
|
|
@ -1376,7 +1369,7 @@ namespace {
|
|||
|
||||
pos.do_null_move(st);
|
||||
|
||||
nullValue = -search(pos, ss, -(beta-1), depth-R*OnePly, ply+1, FORBID_NULLMOVE, threadID);
|
||||
nullValue = -search(pos, ss, -(beta-1), depth-R*OnePly, ply+1, false, threadID);
|
||||
|
||||
pos.undo_null_move();
|
||||
|
||||
|
|
@ -1386,20 +1379,13 @@ namespace {
|
|||
if (nullValue >= value_mate_in(PLY_MAX))
|
||||
nullValue = beta;
|
||||
|
||||
// Do zugzwang verification search for high depths, don't store in TT
|
||||
// if search was stopped.
|
||||
if ( ( depth < 6 * OnePly
|
||||
|| search(pos, ss, beta, depth-5*OnePly, ply, VERIFY_NULLMOVE, threadID) >= beta)
|
||||
&& !AbortSearch
|
||||
&& !TM.thread_should_stop(threadID))
|
||||
{
|
||||
assert(value_to_tt(nullValue, ply) == nullValue);
|
||||
|
||||
if (!tte)
|
||||
TT.store(posKey, nullValue, VALUE_TYPE_NS_LO, depth, MOVE_NONE);
|
||||
|
||||
if (depth < 6 * OnePly)
|
||||
return nullValue;
|
||||
|
||||
// Do zugzwang verification search
|
||||
Value v = search(pos, ss, beta, depth-5*OnePly, ply, false, threadID);
|
||||
if (v >= beta)
|
||||
return nullValue;
|
||||
}
|
||||
} else {
|
||||
// The null move failed low, which means that we may be faced with
|
||||
// some kind of threat. If the previous move was reduced, check if
|
||||
|
|
@ -1424,7 +1410,7 @@ namespace {
|
|||
&& !isCheck
|
||||
&& ss[ply].eval >= beta - IIDMargin)
|
||||
{
|
||||
search(pos, ss, beta, depth/2, ply, FORBID_NULLMOVE, threadID);
|
||||
search(pos, ss, beta, depth/2, ply, false, threadID);
|
||||
ttMove = ss[ply].pv[ply];
|
||||
tte = TT.retrieve(posKey);
|
||||
}
|
||||
|
|
@ -1466,7 +1452,7 @@ namespace {
|
|||
|
||||
if (abs(ttValue) < VALUE_KNOWN_WIN)
|
||||
{
|
||||
Value excValue = search(pos, ss, ttValue - SingularExtensionMargin, depth / 2, ply, FORBID_NULLMOVE, threadID, move);
|
||||
Value excValue = search(pos, ss, ttValue - SingularExtensionMargin, depth / 2, ply, false, threadID, move);
|
||||
|
||||
if (excValue < ttValue - SingularExtensionMargin)
|
||||
ext = OnePly;
|
||||
|
|
@ -1520,7 +1506,7 @@ namespace {
|
|||
ss[ply].reduction = nonpv_reduction(depth, moveCount);
|
||||
if (ss[ply].reduction)
|
||||
{
|
||||
value = -search(pos, ss, -(beta-1), newDepth-ss[ply].reduction, ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -(beta-1), newDepth-ss[ply].reduction, ply+1, true, threadID);
|
||||
doFullDepthSearch = (value >= beta);
|
||||
}
|
||||
}
|
||||
|
|
@ -1529,7 +1515,7 @@ namespace {
|
|||
if (doFullDepthSearch)
|
||||
{
|
||||
ss[ply].reduction = Depth(0);
|
||||
value = -search(pos, ss, -(beta-1), newDepth, ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -(beta-1), newDepth, ply+1, true, threadID);
|
||||
}
|
||||
|
||||
// Step 16. Undo move
|
||||
|
|
@ -1634,7 +1620,7 @@ namespace {
|
|||
tte = TT.retrieve(pos.get_key());
|
||||
ttMove = (tte ? tte->move() : MOVE_NONE);
|
||||
|
||||
if (!pvNode && tte && ok_to_use_TT(tte, depth, beta, ply, true))
|
||||
if (!pvNode && tte && ok_to_use_TT(tte, depth, beta, ply))
|
||||
{
|
||||
assert(tte->type() != VALUE_TYPE_EVAL);
|
||||
|
||||
|
|
@ -1879,7 +1865,7 @@ namespace {
|
|||
ss[sp->ply].reduction = nonpv_reduction(sp->depth, moveCount);
|
||||
if (ss[sp->ply].reduction)
|
||||
{
|
||||
value = -search(pos, ss, -(sp->beta-1), newDepth-ss[sp->ply].reduction, sp->ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -(sp->beta-1), newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID);
|
||||
doFullDepthSearch = (value >= sp->beta && !TM.thread_should_stop(threadID));
|
||||
}
|
||||
}
|
||||
|
|
@ -1888,7 +1874,7 @@ namespace {
|
|||
if (doFullDepthSearch)
|
||||
{
|
||||
ss[sp->ply].reduction = Depth(0);
|
||||
value = -search(pos, ss, -(sp->beta - 1), newDepth, sp->ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -(sp->beta - 1), newDepth, sp->ply+1, true, threadID);
|
||||
}
|
||||
|
||||
// Step 16. Undo move
|
||||
|
|
@ -1985,7 +1971,7 @@ namespace {
|
|||
if (ss[sp->ply].reduction)
|
||||
{
|
||||
Value localAlpha = sp->alpha;
|
||||
value = -search(pos, ss, -localAlpha, newDepth-ss[sp->ply].reduction, sp->ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -localAlpha, newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID);
|
||||
doFullDepthSearch = (value > localAlpha && !TM.thread_should_stop(threadID));
|
||||
}
|
||||
}
|
||||
|
|
@ -1995,7 +1981,7 @@ namespace {
|
|||
{
|
||||
Value localAlpha = sp->alpha;
|
||||
ss[sp->ply].reduction = Depth(0);
|
||||
value = -search(pos, ss, -localAlpha, newDepth, sp->ply+1, ALLOW_NULLMOVE, threadID);
|
||||
value = -search(pos, ss, -localAlpha, newDepth, sp->ply+1, true, threadID);
|
||||
|
||||
if (value > localAlpha && value < sp->beta && !TM.thread_should_stop(threadID))
|
||||
{
|
||||
|
|
@ -2315,18 +2301,14 @@ namespace {
|
|||
}
|
||||
|
||||
|
||||
// ok_to_use_TT() returns true if a transposition table score can be used at a
|
||||
// given point in search. To avoid zugzwang issues TT cutoffs at the root node
|
||||
// of a null move verification search are not allowed if the TT value was found
|
||||
// by a null search, this is implemented testing allowNullmove and TT entry type.
|
||||
// ok_to_use_TT() returns true if a transposition table score
|
||||
// can be used at a given point in search.
|
||||
|
||||
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply, bool allowNullmove) {
|
||||
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply) {
|
||||
|
||||
Value v = value_from_tt(tte->value(), ply);
|
||||
|
||||
return (allowNullmove || !(tte->type() & VALUE_TYPE_NULL))
|
||||
|
||||
&& ( tte->depth() >= depth
|
||||
return ( tte->depth() >= depth
|
||||
|| v >= Max(value_mate_in(PLY_MAX), beta)
|
||||
|| v < Min(value_mated_in(PLY_MAX), beta))
|
||||
|
||||
|
|
|
|||
8
src/tt.h
8
src/tt.h
|
|
@ -46,8 +46,8 @@
|
|||
/// the 32 bits of the data field are so defined
|
||||
///
|
||||
/// bit 0-16: move
|
||||
/// bit 17-18: not used
|
||||
/// bit 19-22: value type
|
||||
/// bit 17-19: not used
|
||||
/// bit 20-22: value type
|
||||
/// bit 23-31: generation
|
||||
|
||||
class TTEntry {
|
||||
|
|
@ -55,14 +55,14 @@ class TTEntry {
|
|||
public:
|
||||
TTEntry() {}
|
||||
TTEntry(uint32_t k, Value v, ValueType t, Depth d, Move m, int generation)
|
||||
: key_ (k), data((m & 0x1FFFF) | (t << 19) | (generation << 23)),
|
||||
: key_ (k), data((m & 0x1FFFF) | (t << 20) | (generation << 23)),
|
||||
value_(int16_t(v)), depth_(int16_t(d)) {}
|
||||
|
||||
uint32_t key() const { return key_; }
|
||||
Depth depth() const { return Depth(depth_); }
|
||||
Move move() const { return Move(data & 0x1FFFF); }
|
||||
Value value() const { return Value(value_); }
|
||||
ValueType type() const { return ValueType((data >> 19) & 0xF); }
|
||||
ValueType type() const { return ValueType((data >> 20) & 7); }
|
||||
int generation() const { return (data >> 23); }
|
||||
|
||||
private:
|
||||
|
|
|
|||
|
|
@ -36,13 +36,11 @@ enum ValueType {
|
|||
VALUE_TYPE_NONE = 0,
|
||||
VALUE_TYPE_UPPER = 1, // Upper bound
|
||||
VALUE_TYPE_LOWER = 2, // Lower bound
|
||||
VALUE_TYPE_EXACT = 3, // Exact score
|
||||
VALUE_TYPE_EVAL = 4, // Static evaluation value
|
||||
VALUE_TYPE_NULL = 8, // Null search value
|
||||
|
||||
VALUE_TYPE_EXACT = VALUE_TYPE_UPPER | VALUE_TYPE_LOWER,
|
||||
VALUE_TYPE_EV_UP = VALUE_TYPE_EVAL | VALUE_TYPE_UPPER,
|
||||
VALUE_TYPE_EV_LO = VALUE_TYPE_EVAL | VALUE_TYPE_LOWER,
|
||||
VALUE_TYPE_NS_LO = VALUE_TYPE_NULL | VALUE_TYPE_LOWER
|
||||
VALUE_TYPE_EV_LO = VALUE_TYPE_EVAL | VALUE_TYPE_LOWER
|
||||
};
|
||||
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue