From 877b468e3e8a3b7f7482266007237c6974f7f282 Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Sat, 15 Jan 2011 11:21:00 +0100 Subject: [PATCH] Partially restore HistoryMax Should be not useful but better safe than sorry. No functional change. Signed-off-by: Marco Costalba --- src/history.h | 10 ++++------ src/movepick.cpp | 4 ++-- 2 files changed, 6 insertions(+), 8 deletions(-) diff --git a/src/history.h b/src/history.h index 9206cdf4..47543d54 100644 --- a/src/history.h +++ b/src/history.h @@ -45,6 +45,8 @@ public: Value gain(Piece p, Square to) const; void update_gain(Piece p, Square to, Value delta); + static const int MaxValue = (1 << 29); // To avoid an overflow + private: Value history[16][64]; // [piece][to_square] Value maxGains[16][64]; // [piece][to_square] @@ -60,7 +62,7 @@ inline int History::value(Piece p, Square to) const { } inline void History::update(Piece p, Square to, Value bonus) { - history[p][to] += bonus; + if (abs(history[p][to]) < MaxValue) history[p][to] += bonus; } inline Value History::gain(Piece p, Square to) const { @@ -68,11 +70,7 @@ inline Value History::gain(Piece p, Square to) const { } inline void History::update_gain(Piece p, Square to, Value gain) { - - if (gain >= maxGains[p][to]) - maxGains[p][to] = gain; - else - maxGains[p][to]--; + maxGains[p][to] = (gain >= maxGains[p][to] ? gain : maxGains[p][to] - 1); } #endif // !defined(HISTORY_H_INCLUDED) diff --git a/src/movepick.cpp b/src/movepick.cpp index ab79c22f..aa6f7c19 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -247,10 +247,10 @@ void MovePicker::score_evasions() { { m = cur->move; if ((seeScore = pos.see_sign(m)) < 0) - cur->score = seeScore - (1 << 29); // Be sure are at the bottom + cur->score = seeScore - History::MaxValue; // Be sure we are at the bottom else if (pos.move_is_capture(m)) cur->score = pos.midgame_value_of_piece_on(move_to(m)) - - pos.type_of_piece_on(move_from(m)) + (1 << 29); + - pos.type_of_piece_on(move_from(m)) + History::MaxValue; else cur->score = H.value(pos.piece_on(move_from(m)), move_to(m)); } -- 2.39.2