Introduce Cut/All node definitions

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index e9c0ad26a27b1ba13e063c3d8d64ec7350c6491f..4ca9e9b8c0f834d8ccbcf91e3defdeae9fed24bd 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -91,7 +91,7 @@ namespace {
   CountermovesStats Countermoves;
 
   template <NodeType NT>
-  Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
+  Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, bool cutNode);
 
   template <NodeType NT, bool InCheck>
   Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
@@ -349,7 +349,7 @@ namespace {
             // research with bigger window until not failing high/low anymore.
             while (true)
             {
-                bestValue = search<Root>(pos, ss, alpha, beta, depth * ONE_PLY);
+                bestValue = search<Root>(pos, ss, alpha, beta, depth * ONE_PLY, false);
 
                 // Bring to front the best move. It is critical that sorting is
                 // done with a stable algorithm because all the values but the first
@@ -455,7 +455,7 @@ namespace {
                 Value rBeta = bestValue - 2 * PawnValueMg;
                 ss->excludedMove = RootMoves[0].pv[0];
                 ss->skipNullMove = true;
-                Value v = search<NonPV>(pos, ss, rBeta - 1, rBeta, (depth - 3) * ONE_PLY);
+                Value v = search<NonPV>(pos, ss, rBeta - 1, rBeta, (depth - 3) * ONE_PLY, true);
                 ss->skipNullMove = false;
                 ss->excludedMove = MOVE_NONE;
 
@@ -485,7 +485,7 @@ namespace {
   // here: This is taken care of after we return from the split point.
 
   template <NodeType NT>
-  Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth) {
+  Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, bool cutNode) {
 
     const bool PvNode   = (NT == PV || NT == Root || NT == SplitPointPV || NT == SplitPointRoot);
     const bool SpNode   = (NT == SplitPointPV || NT == SplitPointNonPV || NT == SplitPointRoot);
@@ -679,7 +679,7 @@ namespace {
         pos.do_null_move(st);
         (ss+1)->skipNullMove = true;
         nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -alpha, DEPTH_ZERO)
-                                      : - search<NonPV>(pos, ss+1, -beta, -alpha, depth-R);
+                                      : - search<NonPV>(pos, ss+1, -beta, -alpha, depth-R, !cutNode);
         (ss+1)->skipNullMove = false;
         pos.undo_null_move();
 
@@ -694,7 +694,7 @@ namespace {
 
             // Do verification search at high depths
             ss->skipNullMove = true;
-            Value v = search<NonPV>(pos, ss, alpha, beta, depth-R);
+            Value v = search<NonPV>(pos, ss, alpha, beta, depth-R, false);
             ss->skipNullMove = false;
 
             if (v >= beta)
@@ -744,7 +744,7 @@ namespace {
             {
                 ss->currentMove = move;
                 pos.do_move(move, st, ci, pos.move_gives_check(move, ci));
-                value = -search<NonPV>(pos, ss+1, -rbeta, -rbeta+1, rdepth);
+                value = -search<NonPV>(pos, ss+1, -rbeta, -rbeta+1, rdepth, !cutNode);
                 pos.undo_move(move);
                 if (value >= rbeta)
                     return value;
@@ -759,7 +759,7 @@ namespace {
         Depth d = depth - 2 * ONE_PLY - (PvNode ? DEPTH_ZERO : depth / 4);
 
         ss->skipNullMove = true;
-        search<PvNode ? PV : NonPV>(pos, ss, alpha, beta, d);
+        search<PvNode ? PV : NonPV>(pos, ss, alpha, beta, d, true);
         ss->skipNullMove = false;
 
         tte = TT.probe(posKey);
@@ -855,7 +855,7 @@ split_point_start: // At split points actual search starts from here
           Value rBeta = ttValue - int(depth);
           ss->excludedMove = move;
           ss->skipNullMove = true;
-          value = search<NonPV>(pos, ss, rBeta - 1, rBeta, depth / 2);
+          value = search<NonPV>(pos, ss, rBeta - 1, rBeta, depth / 2, cutNode);
           ss->skipNullMove = false;
           ss->excludedMove = MOVE_NONE;
 
@@ -955,7 +955,7 @@ split_point_start: // At split points actual search starts from here
           if (SpNode)
               alpha = splitPoint->alpha;
 
-          value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d);
+          value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, true);
 
           doFullDepthSearch = (value > alpha && ss->reduction != DEPTH_ZERO);
           ss->reduction = DEPTH_ZERO;
@@ -972,7 +972,7 @@ split_point_start: // At split points actual search starts from here
           value = newDepth < ONE_PLY ?
                           givesCheck ? -qsearch<NonPV,  true>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO)
                                      : -qsearch<NonPV, false>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO)
-                                     : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth);
+                                     : - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth, !cutNode);
       }
 
       // Only for PV nodes do a full PV search on the first move or after a fail
@@ -982,7 +982,7 @@ split_point_start: // At split points actual search starts from here
           value = newDepth < ONE_PLY ?
                           givesCheck ? -qsearch<PV,  true>(pos, ss+1, -beta, -alpha, DEPTH_ZERO)
                                      : -qsearch<PV, false>(pos, ss+1, -beta, -alpha, DEPTH_ZERO)
-                                     : - search<PV>(pos, ss+1, -beta, -alpha, newDepth);
+                                     : - search<PV>(pos, ss+1, -beta, -alpha, newDepth, false);
       // Step 17. Undo move
       pos.undo_move(move);
 
@@ -1057,7 +1057,7 @@ split_point_start: // At split points actual search starts from here
           assert(bestValue < beta);
 
           thisThread->split<FakeSplit>(pos, ss, alpha, beta, &bestValue, &bestMove,
-                                       depth, threatMove, moveCount, &mp, NT);
+                                       depth, threatMove, moveCount, &mp, NT, cutNode);
           if (bestValue >= beta)
               break;
       }
@@ -1705,13 +1705,13 @@ void Thread::idle_loop() {
 
           switch (sp->nodeType) {
           case Root:
-              search<SplitPointRoot>(pos, ss, sp->alpha, sp->beta, sp->depth);
+              search<SplitPointRoot>(pos, ss, sp->alpha, sp->beta, sp->depth, sp->cutNode);
               break;
           case PV:
-              search<SplitPointPV>(pos, ss, sp->alpha, sp->beta, sp->depth);
+              search<SplitPointPV>(pos, ss, sp->alpha, sp->beta, sp->depth, sp->cutNode);
               break;
           case NonPV:
-              search<SplitPointNonPV>(pos, ss, sp->alpha, sp->beta, sp->depth);
+              search<SplitPointNonPV>(pos, ss, sp->alpha, sp->beta, sp->depth, sp->cutNode);
               break;
           default:
               assert(false);