Introduce pawn structure based history

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index d2a49706fc27e34a5b75d0179cb9f16f7cec8d72..444477cf78efb9c086742aac25ddf0142d48527f 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -89,12 +89,14 @@ MovePicker::MovePicker(const Position&              p,
                        const ButterflyHistory*      mh,
                        const CapturePieceToHistory* cph,
                        const PieceToHistory**       ch,
+                       const PawnHistory&           ph,
                        Move                         cm,
                        const Move*                  killers) :
     pos(p),
     mainHistory(mh),
     captureHistory(cph),
     continuationHistory(ch),
+    pawnHistory(ph),
     ttMove(ttm),
     refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}},
     depth(d) {
@@ -110,11 +112,13 @@ MovePicker::MovePicker(const Position&              p,
                        const ButterflyHistory*      mh,
                        const CapturePieceToHistory* cph,
                        const PieceToHistory**       ch,
+                       const PawnHistory&           ph,
                        Square                       rs) :
     pos(p),
     mainHistory(mh),
     captureHistory(cph),
     continuationHistory(ch),
+    pawnHistory(ph),
     ttMove(ttm),
     recaptureSquare(rs),
     depth(d) {
@@ -125,9 +129,11 @@ MovePicker::MovePicker(const Position&              p,
 
 // Constructor for ProbCut: we generate captures with SEE greater
 // than or equal to the given threshold.
-MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph) :
+MovePicker::MovePicker(
+  const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph, const PawnHistory& ph) :
     pos(p),
     captureHistory(cph),
+    pawnHistory(ph),
     ttMove(ttm),
     threshold(th) {
     assert(!pos.checkers());
@@ -203,6 +209,8 @@ void MovePicker::score() {
                           : pt != PAWN ? bool(to & threatenedByPawn) * 15000
                                        : 0)
                        : 0;
+
+            m.value += pawnHistory[pawn_structure(pos)][pc][to];
         }
 
         else  // Type == EVASIONS
@@ -212,7 +220,8 @@ void MovePicker::score() {
                         + (1 << 28);
             else
                 m.value = (*mainHistory)[pos.side_to_move()][from_to(m)]
-                        + (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)];
+                        + (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
+                        + pawnHistory[pawn_structure(pos)][pos.moved_piece(m)][to_sq(m)];
         }
 }