Speed up polynomial material imbalance loop

[stockfish] / src / material.cpp

diff --git a/src/material.cpp b/src/material.cpp
index eb271e8c94b6701c7eab1a308a451454f242cd76..27ea5923b492fc9caeb548a29e8dab6c1369da91 100644 (file)
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -41,17 +41,17 @@ namespace {
   const Value BishopPairEndgameBonus = Value(97);
 
   // Polynomial material balance parameters
-  const Value RedundantQueenPenalty = Value(358);
-  const Value RedundantRookPenalty  = Value(536);
-  const int LinearCoefficients[6]   = { 1740, -146, -1246, -197, 206, -7 };
+  const Value RedundantQueenPenalty = Value(320);
+  const Value RedundantRookPenalty  = Value(554);
+  const int LinearCoefficients[6]   = { 1709, -137, -1185, -166, 141, 59 };
 
   const int QuadraticCoefficientsSameColor[][6] = {
-  { 0, 0, 0, 0, 0, 0 }, { 31, -4, 0, 0, 0, 0 }, { 14, 267, -21, 0, 0, 0 },
-  { 0, 7, -26, 0, 0, 0 }, { -3, -1, 69, 162, 80, 0 }, { 40, 27, 119, 174, -64, -49 } };
+  { 0, 0, 0, 0, 0, 0 }, { 33, -6, 0, 0, 0, 0 }, { 29, 269, -12, 0, 0, 0 },
+  { 0, 19, -4, 0, 0, 0 }, { -35, -10, 40, 95, 50, 0 }, { 52, 23, 78, 144, -11, -33 } };
 
   const int QuadraticCoefficientsOppositeColor[][6] = {
-  { 0, 0, 0, 0, 0, 0 }, { -9, 0, 0, 0, 0, 0 }, { 49, 32, 0, 0, 0, 0 },
-  { -25, 19, -5, 0, 0, 0 }, { 97, -6, 39, -88, 0, 0 }, { 77, 69, -42, 104, 116, 0 } };
+  { 0, 0, 0, 0, 0, 0 }, { -5, 0, 0, 0, 0, 0 }, { -33, 23, 0, 0, 0, 0 },
+  { 17, 25, -3, 0, 0, 0 }, { 10, -2, -19, -67, 0, 0 }, { 69, 64, -41, 116, 137, 0 } };
 
   // Unmapped endgame evaluation and scaling functions, these
   // are accessed direcly and not through the function maps.
@@ -61,8 +61,6 @@ namespace {
   ScalingFunction<KQKRP>    ScaleKQKRP(WHITE),  ScaleKRPKQ(BLACK);
   ScalingFunction<KPsK>     ScaleKPsK(WHITE),   ScaleKKPs(BLACK);
   ScalingFunction<KPKP>     ScaleKPKPw(WHITE),  ScaleKPKPb(BLACK);
-
-  Key KNNKMaterialKey, KKNNMaterialKey;
 }
 
 
@@ -157,14 +155,6 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
   mi->clear();
   mi->key = key;
 
-  // A special case before looking for a specialized evaluation function
-  // KNN vs K is a draw.
-  if (key == KNNKMaterialKey || key == KKNNMaterialKey)
-  {
-      mi->factor[WHITE] = mi->factor[BLACK] = 0;
-      return mi;
-  }
-
   // Let's look if we have a specialized evaluation function for this
   // particular material configuration. First we look for a fixed
   // configuration one, then a generic one if previous search failed.
@@ -273,8 +263,10 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
   }
 
   // Evaluate the material balance
-
-  const int bishopsPair_count[2] = { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(BLACK, BISHOP) > 1 };
+  const int pieceCount[2][6] = { { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(WHITE, PAWN), pos.piece_count(WHITE, KNIGHT),
+                                   pos.piece_count(WHITE, BISHOP), pos.piece_count(WHITE, ROOK), pos.piece_count(WHITE, QUEEN) },
+                                 { pos.piece_count(BLACK, BISHOP) > 1, pos.piece_count(BLACK, PAWN), pos.piece_count(BLACK, KNIGHT),
+                                   pos.piece_count(BLACK, BISHOP), pos.piece_count(BLACK, ROOK), pos.piece_count(BLACK, QUEEN) } };
   Color c, them;
   int sign;
   int matValue = 0;
@@ -307,29 +299,26 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
     // Redundancy of major pieces, formula based on Kaufman's paper
     // "The Evaluation of Material Imbalances in Chess"
     // http://mywebpages.comcast.net/danheisman/Articles/evaluation_of_material_imbalance.htm
-    if (pos.piece_count(c, ROOK) >= 1)
-        matValue -= sign * ((pos.piece_count(c, ROOK) - 1) * RedundantRookPenalty + pos.piece_count(c, QUEEN) * RedundantQueenPenalty);
+    if (pieceCount[c][ROOK] >= 1)
+        matValue -= sign * ((pieceCount[c][ROOK] - 1) * RedundantRookPenalty + pieceCount[c][QUEEN] * RedundantQueenPenalty);
 
     // Second-degree polynomial material imbalance by Tord Romstad
     //
     // We use NO_PIECE_TYPE as a place holder for the bishop pair "extended piece",
     // this allow us to be more flexible in defining bishop pair bonuses.
     them = opposite_color(c);
-    for (PieceType pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
+    for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
     {
-        int c1, c2, c3;
-        c1 = sign * (pt1 != NO_PIECE_TYPE ? pos.piece_count(c, pt1) : bishopsPair_count[c]);
+        int c1 = sign * pieceCount[c][pt1];
         if (!c1)
             continue;
 
         matValue += c1 * LinearCoefficients[pt1];
 
-        for (PieceType pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
+        for (int pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
         {
-            c2 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(c,    pt2) : bishopsPair_count[c]);
-            c3 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(them, pt2) : bishopsPair_count[them]);
-            matValue += c1 * c2 * QuadraticCoefficientsSameColor[pt1][pt2];
-            matValue += c1 * c3 * QuadraticCoefficientsOppositeColor[pt1][pt2];
+            matValue += c1 * pieceCount[c][pt2] * QuadraticCoefficientsSameColor[pt1][pt2];
+            matValue += c1 * pieceCount[them][pt2] * QuadraticCoefficientsOppositeColor[pt1][pt2];
         }
     }
   }
@@ -348,9 +337,7 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
 
 EndgameFunctions::EndgameFunctions() {
 
-  KNNKMaterialKey = buildKey("KNNK");
-  KKNNMaterialKey = buildKey("KKNN");
-
+  add<EvaluationFunction<KNNK>  >("KNNK");
   add<EvaluationFunction<KPK>   >("KPK");
   add<EvaluationFunction<KBNK>  >("KBNK");
   add<EvaluationFunction<KRKP>  >("KRKP");