X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fhistory.cpp;h=6849839ca2305161b24b32e4be106de833126c2f;hp=29631489aac7c5e1e2e37f53f764f51a76e5a2bc;hb=3e38e61565c9ee6e3ff83dddfae22908bd2594b4;hpb=bb751d6c890f5c50c642366d601740366cfae8d0

diff --git a/src/history.cpp b/src/history.cpp
index 29631489..6849839c 100644
--- a/src/history.cpp
+++ b/src/history.cpp
@@ -1,17 +1,18 @@
 /*
-  Glaurung, a UCI chess playing engine.
-  Copyright (C) 2004-2008 Tord Romstad
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+  Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
 
-  Glaurung is free software: you can redistribute it and/or modify
+  Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
-  
-  Glaurung is distributed in the hope that it will be useful,
+
+  Stockfish is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
-  
+
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -22,6 +23,7 @@
 ////
 
 #include <cassert>
+#include <cstring>
 
 #include "history.h"
 
@@ -30,71 +32,67 @@
 //// Functions
 ////
 
+
 /// Constructor
 
-History::History() {
-  this->clear();
-}
+History::History() { clear(); }
 
 
-/// History::clear() clears the history tables.
+/// History::clear() clears the history tables
 
 void History::clear() {
-  memset(history, 0, 2 * 8 * 64 * sizeof(int));
-  memset(successCount, 0, 2 * 8 * 64 * sizeof(int));
-  memset(failureCount, 0, 2 * 8 * 64 * sizeof(int));
+  memset(history, 0, 16 * 64 * sizeof(int));
+  memset(maxStaticValueDelta, 0, 16 * 64 * sizeof(int));
 }
 
 
-/// History::success() registers a move as being successful.  This is done
+/// History::success() registers a move as being successful. This is done
 /// whenever a non-capturing move causes a beta cutoff in the main search.
-/// The three parameters are the moving piece, the move itself, and the
-/// search depth.
+/// The three parameters are the moving piece, the destination square, and
+/// the search depth.
+
+void History::success(Piece p, Square to, Depth d) {
 
-void History::success(Piece p, Move m, Depth d) {
   assert(piece_is_ok(p));
-  assert(move_is_ok(m));
+  assert(square_is_ok(to));
 
-  history[p][move_to(m)] += int(d) * int(d);
-  successCount[p][move_to(m)]++;
+  history[p][to] += int(d) * int(d);
 
-  // Prevent history overflow:
-  if(history[p][move_to(m)] >= HistoryMax)
-    for(int i = 0; i < 16; i++)
-      for(int j = 0; j < 64; j++)
-        history[i][j] /= 2;
+  // Prevent history overflow
+  if (history[p][to] >= HistoryMax)
+      for (int i = 0; i < 16; i++)
+          for (int j = 0; j < 64; j++)
+              history[i][j] /= 2;
 }
 
 
-/// History::failure() registers a move as being unsuccessful.  The function is
+/// History::failure() registers a move as being unsuccessful. The function is
 /// called for each non-capturing move which failed to produce a beta cutoff
 /// at a node where a beta cutoff was finally found.
 
-void History::failure(Piece p, Move m) {
-  assert(piece_is_ok(p));
-  assert(move_is_ok(m));
-
-  failureCount[p][move_to(m)]++;
-}
-
+void History::failure(Piece p, Square to, Depth d) {
 
-/// History::move_ordering_score() returns an integer value used to order the
-/// non-capturing moves in the MovePicker class.
-
-int History::move_ordering_score(Piece p, Move m) const {
   assert(piece_is_ok(p));
-  assert(move_is_ok(m));
+  assert(square_is_ok(to));
+
+  history[p][to] -= int(d) * int(d);
 
-  return history[p][move_to(m)];
+  // Prevent history underflow
+  if (history[p][to] <= -HistoryMax)
+      for (int i = 0; i < 16; i++)
+          for (int j = 0; j < 64; j++)
+              history[i][j] /= 2;
 }
 
 
-/// History::ok_to_prune() decides whether a move has been sufficiently
-/// unsuccessful that it makes sense to prune it entirely. 
+/// History::set_gain() and History::gain() store and retrieve the
+/// gain of a move given the delta of the static position evaluations
+/// before and after the move.
 
-bool History::ok_to_prune(Piece p, Move m, Depth d) const {
-  assert(piece_is_ok(p));
-  assert(move_is_ok(m));
+void History::set_gain(Piece p, Square to, Value delta) {
 
-  return (int(d) * successCount[p][move_to(m)] < failureCount[p][move_to(m)]);
+  if (delta >= maxStaticValueDelta[p][to])
+      maxStaticValueDelta[p][to] = delta;
+  else
+      maxStaticValueDelta[p][to]--;
 }