X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=7cf4a8a3b583054b651d17b7c422564e859a7296;hp=5ea00331b9bd85b012f66f473295c092e0808066;hb=158864270a055fe20dca4a87f4b7a8aa9cedfeb9;hpb=ba1464751d1186f723a2d2a5d18c06ddfc9a4cb3 diff --git a/src/search.cpp b/src/search.cpp index 5ea00331..7cf4a8a3 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -27,7 +27,7 @@ #include "evaluate.h" #include "movegen.h" #include "movepick.h" -#include "rkiss.h" +#include "misc.h" #include "search.h" #include "timeman.h" #include "thread.h" @@ -195,9 +195,9 @@ void Search::think() { TimeMgr.init(Limits, RootPos.game_ply(), RootPos.side_to_move()); - int cf = Options["Contempt"] * PawnValueEg / 100; // From centipawns - DrawValue[ RootPos.side_to_move()] = VALUE_DRAW - Value(cf); - DrawValue[~RootPos.side_to_move()] = VALUE_DRAW + Value(cf); + int contempt = Options["Contempt"] * PawnValueEg / 100; // From centipawns + DrawValue[ RootPos.side_to_move()] = VALUE_DRAW - Value(contempt); + DrawValue[~RootPos.side_to_move()] = VALUE_DRAW + Value(contempt); TB::Hits = 0; TB::RootInTB = false; @@ -324,7 +324,7 @@ namespace { // Save the last iteration's scores before first PV line is searched and // all the move scores except the (new) PV are set to -VALUE_INFINITE. for (size_t i = 0; i < RootMoves.size(); ++i) - RootMoves[i].prevScore = RootMoves[i].score; + RootMoves[i].previousScore = RootMoves[i].score; // MultiPV loop. We perform a full root search for each PV line for (PVIdx = 0; PVIdx < std::min(multiPV, RootMoves.size()) && !Signals.stop; ++PVIdx) @@ -333,8 +333,8 @@ namespace { if (depth >= 5 * ONE_PLY) { delta = Value(16); - alpha = std::max(RootMoves[PVIdx].prevScore - delta,-VALUE_INFINITE); - beta = std::min(RootMoves[PVIdx].prevScore + delta, VALUE_INFINITE); + alpha = std::max(RootMoves[PVIdx].previousScore - delta,-VALUE_INFINITE); + beta = std::min(RootMoves[PVIdx].previousScore + delta, VALUE_INFINITE); } // Start with a small aspiration window and, in the case of a fail @@ -461,7 +461,7 @@ namespace { SplitPoint* splitPoint; Key posKey; Move ttMove, move, excludedMove, bestMove; - Depth ext, newDepth, predictedDepth; + Depth extension, newDepth, predictedDepth; Value bestValue, value, ttValue, eval, nullValue, futilityValue; bool inCheck, givesCheck, singularExtensionNode, improving; bool captureOrPromotion, dangerous, doFullDepthSearch; @@ -789,7 +789,7 @@ moves_loop: // When in check and at SpNode search starts from here if (PvNode) (ss+1)->pv = NULL; - ext = DEPTH_ZERO; + extension = DEPTH_ZERO; captureOrPromotion = pos.capture_or_promotion(move); givesCheck = type_of(move) == NORMAL && !ci.dcCandidates @@ -802,7 +802,7 @@ moves_loop: // When in check and at SpNode search starts from here // Step 12. Extend checks if (givesCheck && pos.see_sign(move) >= VALUE_ZERO) - ext = ONE_PLY; + extension = ONE_PLY; // Singular extension search. If all moves but one fail low on a search of // (alpha-s, beta-s), and just one fails high on (alpha, beta), then that move @@ -811,7 +811,7 @@ moves_loop: // When in check and at SpNode search starts from here // ttValue minus a margin then we extend the ttMove. if ( singularExtensionNode && move == ttMove - && !ext + && !extension && pos.legal(move, ci.pinned)) { Value rBeta = ttValue - 2 * depth / ONE_PLY; @@ -822,11 +822,11 @@ moves_loop: // When in check and at SpNode search starts from here ss->excludedMove = MOVE_NONE; if (value < rBeta) - ext = ONE_PLY; + extension = ONE_PLY; } // Update the current move (this must be done after singular extension search) - newDepth = depth - ONE_PLY + ext; + newDepth = depth - ONE_PLY + extension; // Step 13. Pruning at shallow depth (exclude PV nodes) if ( !PvNode @@ -1377,16 +1377,13 @@ moves_loop: // When in check and at SpNode search starts from here Move Skill::pick_move() { - static RKISS rk; - - // PRNG sequence should be not deterministic - for (int i = Time::now() % 50; i > 0; --i) - rk.rand(); + // PRNG sequence should be non-deterministic, so we seed it with the time at init + static PRNG rng(Time::now()); // RootMoves are already sorted by score in descending order int variance = std::min(RootMoves[0].score - RootMoves[candidates - 1].score, PawnValueMg); int weakness = 120 - 2 * level; - int max_s = -VALUE_INFINITE; + int maxScore = -VALUE_INFINITE; best = MOVE_NONE; // Choose best move. For each move score we add two terms both dependent on @@ -1394,19 +1391,19 @@ moves_loop: // When in check and at SpNode search starts from here // then we choose the move with the resulting highest score. for (size_t i = 0; i < candidates; ++i) { - int s = RootMoves[i].score; + int score = RootMoves[i].score; // Don't allow crazy blunders even at very low skills - if (i > 0 && RootMoves[i - 1].score > s + 2 * PawnValueMg) + if (i > 0 && RootMoves[i - 1].score > score + 2 * PawnValueMg) break; // This is our magic formula - s += ( weakness * int(RootMoves[0].score - s) - + variance * (rk.rand() % weakness)) / 128; + score += ( weakness * int(RootMoves[0].score - score) + + variance * (rng.rand() % weakness)) / 128; - if (s > max_s) + if (score > maxScore) { - max_s = s; + maxScore = score; best = RootMoves[i].pv[0]; } } @@ -1437,7 +1434,7 @@ moves_loop: // When in check and at SpNode search starts from here continue; Depth d = updated ? depth : depth - ONE_PLY; - Value v = updated ? RootMoves[i].score : RootMoves[i].prevScore; + Value v = updated ? RootMoves[i].score : RootMoves[i].previousScore; bool tb = TB::RootInTB && abs(v) < VALUE_MATE - MAX_PLY; v = tb ? TB::Score : v;