X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=43fb7067a4692a0ca8915c68316215125e109261;hp=44bd9530d3e6a5f362de24fcb1ce438b5e86d24c;hb=c01af5676913cbb8a522bd080b6d8559c7450f3a;hpb=e817a55bc6cc60b831f74ce5c180ec8b07c41d8a diff --git a/src/search.cpp b/src/search.cpp index 44bd9530..43fb7067 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -652,6 +652,8 @@ void SearchStack::init(int ply) { pv[ply] = pv[ply + 1] = MOVE_NONE; currentMove = threatMove = MOVE_NONE; reduction = Depth(0); + eval = VALUE_NONE; + evalInfo = NULL; } void SearchStack::initKillers() { @@ -885,7 +887,7 @@ namespace { Value root_search(Position& pos, SearchStack ss[], RootMoveList& rml, Value alpha, Value beta) { Value oldAlpha = alpha; - Value value; + Value value = -VALUE_INFINITE; CheckInfo ci(pos); // Loop through all the moves in the root move list @@ -954,6 +956,8 @@ namespace { { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. + bool doFullDepthSearch = true; + if ( depth >= 3*OnePly // FIXME was newDepth && !dangerous && !captureOrPromotion @@ -964,13 +968,11 @@ namespace { { ss[0].reduction = Depth(int(floor(red * int(OnePly)))); value = -search(pos, ss, -alpha, newDepth-ss[0].reduction, 1, true, 0); + doFullDepthSearch = (value > alpha); } - else - value = alpha + 1; // Just to trigger next condition - } else - value = alpha + 1; // Just to trigger next condition + } - if (value > alpha) + if (doFullDepthSearch) { value = -search(pos, ss, -alpha, newDepth, 1, true, 0); @@ -1097,7 +1099,6 @@ namespace { assert(threadID >= 0 && threadID < ActiveThreads); Move movesSearched[256]; - EvalInfo ei; StateInfo st; const TTEntry* tte; Move ttMove, move; @@ -1105,7 +1106,7 @@ namespace { Value oldAlpha, value; bool isCheck, mateThreat, singleEvasion, moveIsCheck, captureOrPromotion, dangerous; int moveCount = 0; - Value bestValue = -VALUE_INFINITE; + Value bestValue = value = -VALUE_INFINITE; if (depth < OnePly) return qsearch(pos, ss, alpha, beta, Depth(0), ply, threadID); @@ -1118,12 +1119,9 @@ namespace { if (AbortSearch || thread_should_stop(threadID)) return Value(0); - if (pos.is_draw()) + if (pos.is_draw() || ply >= PLY_MAX - 1) return VALUE_DRAW; - if (ply >= PLY_MAX - 1) - return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID); - // Mate distance pruning oldAlpha = alpha; alpha = Max(value_mated_in(ply), alpha); @@ -1210,6 +1208,8 @@ namespace { { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. + bool doFullDepthSearch = true; + if ( depth >= 3*OnePly && !dangerous && !captureOrPromotion @@ -1221,14 +1221,11 @@ namespace { { 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); } - else - value = alpha + 1; // Just to trigger next condition } - else - value = alpha + 1; // Just to trigger next condition - if (value > alpha) // Go with full depth non-pv search + if (doFullDepthSearch) // Go with full depth non-pv search { ss[ply].reduction = Depth(0); value = -search(pos, ss, -alpha, newDepth, ply+1, true, threadID); @@ -1331,11 +1328,11 @@ namespace { const TTEntry* tte; Move ttMove, move; Depth ext, newDepth; - Value staticValue, nullValue, value, futilityValue, futilityValueScaled; + Value bestValue, staticValue, nullValue, value, futilityValue, futilityValueScaled; bool isCheck, useFutilityPruning, singleEvasion, moveIsCheck, captureOrPromotion, dangerous; bool mateThreat = false; int moveCount = 0; - Value bestValue = -VALUE_INFINITE; + futilityValue = staticValue = bestValue = value = -VALUE_INFINITE; if (depth < OnePly) return qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID); @@ -1348,12 +1345,9 @@ namespace { if (AbortSearch || thread_should_stop(threadID)) return Value(0); - if (pos.is_draw()) + if (pos.is_draw() || ply >= PLY_MAX - 1) return VALUE_DRAW; - if (ply >= PLY_MAX - 1) - return pos.is_check() ? quick_evaluate(pos) : evaluate(pos, ei, threadID); - // Mate distance pruning if (value_mated_in(ply) >= beta) return beta; @@ -1376,23 +1370,26 @@ namespace { } isCheck = pos.is_check(); - ei.futilityMargin = Value(0); // Manually initialize futilityMargin - - // Evaluate the position statically - if (isCheck) - staticValue = quick_evaluate(pos); - else if (tte && (tte->type() & VALUE_TYPE_EVAL)) - staticValue = value_from_tt(tte->value(), ply); - else - staticValue = evaluate(pos, ei, threadID); // Calculate depth dependant futility pruning parameters const int FutilityMoveCountMargin = 3 + (1 << (3 * int(depth) / 8)); const int FutilityValueMargin = 112 * bitScanReverse32(int(depth) * int(depth) / 2); - // Enhance score accuracy with TT value if possible - futilityValue = staticValue + FutilityValueMargin; - staticValue = refine_eval(tte, staticValue, ply); + // Evaluate the position statically + if (!isCheck) + { + if (tte && (tte->type() & VALUE_TYPE_EVAL)) + staticValue = value_from_tt(tte->value(), ply); + else + { + staticValue = evaluate(pos, ei, threadID); + ss[ply].evalInfo = &ei; + } + + ss[ply].eval = staticValue; + futilityValue = staticValue + FutilityValueMargin; + staticValue = refine_eval(tte, staticValue, ply); // Enhance accuracy with TT value if possible + } // Null move search if ( allowNullmove @@ -1445,8 +1442,9 @@ namespace { } // Null move search not allowed, try razoring else if ( !value_is_mate(beta) + && !isCheck && depth < RazorDepth - && staticValue < beta - (depth > OnePly ? NullMoveMargin + 16 * depth : 2*NullMoveMargin) + && staticValue < beta - (NullMoveMargin + 16 * depth) && ss[ply - 1].currentMove != MOVE_NULL && ttMove == MOVE_NONE && !pos.has_pawn_on_7th(pos.side_to_move())) @@ -1459,7 +1457,7 @@ namespace { // Go with internal iterative deepening if we don't have a TT move if (UseIIDAtNonPVNodes && ttMove == MOVE_NONE && depth >= 8*OnePly && - !isCheck && evaluate(pos, ei, threadID) >= beta - IIDMargin) + !isCheck && ss[ply].eval >= beta - IIDMargin) { search(pos, ss, beta, Min(depth/2, depth-2*OnePly), ply, false, threadID); ttMove = ss[ply].pv[ply]; @@ -1544,6 +1542,8 @@ namespace { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. + bool doFullDepthSearch = true; + if ( depth >= 3*OnePly && !dangerous && !captureOrPromotion @@ -1556,14 +1556,11 @@ namespace { { 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); } - else - value = beta; // Just to trigger next condition } - else - value = beta; // Just to trigger next condition - if (value >= beta) // Go with full depth non-pv search + if (doFullDepthSearch) // Go with full depth non-pv search { ss[ply].reduction = Depth(0); value = -search(pos, ss, -(beta-1), newDepth, ply+1, true, threadID); @@ -1657,12 +1654,9 @@ namespace { if (AbortSearch || thread_should_stop(threadID)) return Value(0); - if (pos.is_draw()) + if (pos.is_draw() || ply >= PLY_MAX - 1) return VALUE_DRAW; - 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()); @@ -1677,7 +1671,6 @@ namespace { } isCheck = pos.is_check(); - ei.futilityMargin = Value(0); // Manually initialize futilityMargin // Evaluate the position statically if (isCheck) @@ -1817,14 +1810,13 @@ namespace { Position pos = Position(sp->pos); CheckInfo ci(pos); SearchStack* ss = sp->sstack[threadID]; - Value value; + Value value = -VALUE_INFINITE; Move move; bool isCheck = pos.is_check(); bool useFutilityPruning = sp->depth < SelectiveDepth && !isCheck; const int FutilityMoveCountMargin = 3 + (1 << (3 * int(sp->depth) / 8)); - const int FutilityValueMargin = 112 * bitScanReverse32(int(sp->depth) * int(sp->depth) / 2); while ( sp->bestValue < sp->beta && !thread_should_stop(threadID) @@ -1858,12 +1850,6 @@ namespace { continue; // Value based pruning - if (sp->futilityValue == VALUE_NONE) - { - EvalInfo ei; - sp->futilityValue = evaluate(pos, ei, threadID) + FutilityValueMargin; - } - Value futilityValueScaled = sp->futilityValue - moveCount * IncrementalFutilityMargin; if (futilityValueScaled < sp->beta) @@ -1885,6 +1871,8 @@ namespace { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. + bool doFullDepthSearch = true; + if ( !dangerous && !captureOrPromotion && !move_is_castle(move) @@ -1895,14 +1883,11 @@ namespace { { 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); } - else - value = sp->beta; // Just to trigger next condition } - else - value = sp->beta; // Just to trigger next condition - if (value >= sp->beta) // Go with full depth non-pv search + if (doFullDepthSearch) // Go with full depth non-pv search { ss[sp->ply].reduction = Depth(0); value = -search(pos, ss, -(sp->beta - 1), newDepth, sp->ply+1, true, threadID); @@ -1967,7 +1952,7 @@ namespace { Position pos = Position(sp->pos); CheckInfo ci(pos); SearchStack* ss = sp->sstack[threadID]; - Value value; + Value value = -VALUE_INFINITE; Move move; while ( sp->alpha < sp->beta @@ -1996,6 +1981,8 @@ namespace { // Try to reduce non-pv search depth by one ply if move seems not problematic, // if the move fails high will be re-searched at full depth. + bool doFullDepthSearch = true; + if ( !dangerous && !captureOrPromotion && !move_is_castle(move) @@ -2004,24 +1991,23 @@ namespace { double red = 0.5 + ln(moveCount) * ln(sp->depth / 2) / 6.0; if (red >= 1.0) { + Value localAlpha = sp->alpha; ss[sp->ply].reduction = Depth(int(floor(red * int(OnePly)))); - value = -search(pos, ss, -sp->alpha, newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID); + value = -search(pos, ss, -localAlpha, newDepth-ss[sp->ply].reduction, sp->ply+1, true, threadID); + doFullDepthSearch = (value > localAlpha); } - else - value = sp->alpha + 1; // Just to trigger next condition } - else - value = sp->alpha + 1; // Just to trigger next condition - if (value > sp->alpha) // Go with full depth non-pv search + if (doFullDepthSearch) // Go with full depth non-pv search { + Value localAlpha = sp->alpha; ss[sp->ply].reduction = Depth(0); - value = -search(pos, ss, -sp->alpha, newDepth, sp->ply+1, true, threadID); + value = -search(pos, ss, -localAlpha, newDepth, sp->ply+1, true, threadID); - if (value > sp->alpha && value < sp->beta) + if (value > localAlpha && value < sp->beta) { // When the search fails high at ply 1 while searching the first - // move at the root, set the flag failHighPly1. This is used for + // move at the root, set the flag failHighPly1. This is used for // time managment: We don't want to stop the search early in // such cases, because resolving the fail high at ply 1 could // result in a big drop in score at the root.