Plumb iImprovement into LMR and futiltiy and parallel search.

Fix a bug (iEval) in HelpSearch
This commit changes the heuristics for: nullmove pruning, LMR, and EFP slightly.

1 files changed, 45 insertions, 42 deletions

diff --git a/src/split.c b/src/split.c
index 8bc4e60..b3fc659 100755
--- a/src/split.c
+++ b/src/split.c
@@ -246,7 +246,7 @@ Return value:
                  v++)
             {
                 ctx->sMoveStack.mvf[v] = g_SplitInfo[u].mvf[v];
-                ASSERT(SanityCheckMove(&ctx->sPosition, 
+                ASSERT(SanityCheckMove(&ctx->sPosition,
                                        g_SplitInfo[u].mvf[v].mv));
             }
 
@@ -459,6 +459,7 @@ SCORE
 StartParallelSearch(IN SEARCHER_THREAD_CONTEXT *ctx,
                     IN OUT SCORE *piAlpha,
                     IN SCORE iBeta,
+                    IN SCORE iImprovement,
                     IN OUT SCORE *piBestScore,
                     IN OUT MOVE *pmvBest,
                     IN ULONG uMoveNum,
@@ -565,6 +566,8 @@ Return value:
             memcpy(&(g_SplitInfo[u].sRootPosition),
                    GetRootPosition(),
                    sizeof(POSITION));
+            g_SplitInfo[u].iEval = ctx->sPlyInfo[ctx->uPly].iEval;
+            g_SplitInfo[u].iImprovement = iImprovement;
 #if DEBUG
             g_SplitInfo[u].uSplitPly = ctx->uPly;
             memcpy(&(g_SplitInfo[u].sSplitPosition),
@@ -579,7 +582,7 @@ Return value:
             // useless.  Before we grab any helper threads, see if we
             // need to bail out of this split.
             //
-            if (g_MoveTimer.bvFlags & TIMER_STOPPING) 
+            if (g_MoveTimer.bvFlags & TIMER_STOPPING)
             {
                 g_uNumSplitsAvailable++;
                 g_SplitInfo[u].uNumThreadsHelping = 0;
@@ -690,11 +693,11 @@ Return value:
             // Update the context of the thread that is initiating the
             // split with a pointer to the split info node we are using.
             //
-            for (uSplitNum = 0; 
-                 uSplitNum < NUM_SPLIT_PTRS_IN_CONTEXT; 
-                 uSplitNum++) 
+            for (uSplitNum = 0;
+                 uSplitNum < NUM_SPLIT_PTRS_IN_CONTEXT;
+                 uSplitNum++)
             {
-                if (ctx->pSplitInfo[uSplitNum] == NULL) 
+                if (ctx->pSplitInfo[uSplitNum] == NULL)
                 {
                     ctx->pSplitInfo[uSplitNum] = &(g_SplitInfo[u]);
                     break;
@@ -726,7 +729,7 @@ Return value:
                 if (g_fExitProgram) break;
             }
 
-            // 
+            //
             // Note: past this point we are the only ones using the
             // split until we return it to the pool by making its
             // refcount zero again.
@@ -848,7 +851,7 @@ Parameters:
     MOVE mv : move it just searched
     SCORE iScore : score of the move's subtree
     ULONG u : split node number
-    
+
 Return value:
 
     static void
@@ -856,13 +859,13 @@ Return value:
 **/
 {
     ULONG v;
-    
+
     AcquireSpinLock(&(g_SplitInfo[u].uLock));
 
     //
     // See if this split is shutting down
     //
-    if (TRUE == g_SplitInfo[u].fTerminate) 
+    if (TRUE == g_SplitInfo[u].fTerminate)
     {
         ReleaseSpinLock(&(g_SplitInfo[u].uLock));
         return;
@@ -909,8 +912,8 @@ Return value:
 }
 
 
-static void 
-_SetFinalStats(IN SEARCHER_THREAD_CONTEXT *ctx, 
+static void
+_SetFinalStats(IN SEARCHER_THREAD_CONTEXT *ctx,
                IN ULONG u)
 /**
 
@@ -934,13 +937,13 @@ Return value:
     // Before we stop searching this node, update some stuff.
     //
     AcquireSpinLock(&(g_SplitInfo[u].uLock));
-    
+
     //
     // Counters to persist in the main counter struct via the split.
     //
-    g_SplitInfo[u].sCounters.tree.u64TotalNodeCount += 
+    g_SplitInfo[u].sCounters.tree.u64TotalNodeCount +=
         ctx->sCounters.tree.u64TotalNodeCount;
-    g_SplitInfo[u].sCounters.tree.u64BetaCutoffs += 
+    g_SplitInfo[u].sCounters.tree.u64BetaCutoffs +=
         ctx->sCounters.tree.u64BetaCutoffs;
     g_SplitInfo[u].sCounters.tree.u64BetaCutoffsOnFirstMove +=
         ctx->sCounters.tree.u64BetaCutoffsOnFirstMove;
@@ -954,11 +957,11 @@ Return value:
     //
     // TODO: Any other counters we care about?
     //
-    
+
     //
     // IDEA: Save the killers from this context to bring back to main
     //
-    
+
     //
     // Decrement threadcount in this split.  Note: the main thread
     // incremented it by two.
@@ -970,18 +973,18 @@ Return value:
 }
 
 
-static MOVE 
-_GetNextParallelMove(OUT SCORE *piAlpha, 
-                     OUT SCORE *piBestScore, 
+static MOVE
+_GetNextParallelMove(OUT SCORE *piAlpha,
+                     OUT SCORE *piBestScore,
                      OUT ULONG *puMoveNumber,
                      IN ULONG u)
 /**
-  
+
 Routine description:
 
     Retrieve the next parallel move to search at the split node.  Also
     update alpha and bestscore.
-    
+
 Parameters:
 
     SCORE *piAlpha : current alpha
@@ -995,7 +998,7 @@ Return value:
 **/
 {
     MOVE mv = {0};
-    
+
     AcquireSpinLock(&(g_SplitInfo[u].uLock));
     if (g_SplitInfo[u].fTerminate)
     {
@@ -1012,7 +1015,7 @@ Return value:
 #ifdef DEBUG
         ASSERT(!(g_SplitInfo[u].mvf[g_SplitInfo[u].uOnDeckMove].bvFlags &
                  MVF_MOVE_SEARCHED));
-        g_SplitInfo[u].mvf[g_SplitInfo[u].uOnDeckMove].bvFlags |= 
+        g_SplitInfo[u].mvf[g_SplitInfo[u].uOnDeckMove].bvFlags |=
             MVF_MOVE_SEARCHED;
         ASSERT(mv.uMove);
         ASSERT(SanityCheckMove(&g_SplitInfo[u].sSplitPosition, mv));
@@ -1029,8 +1032,8 @@ Return value:
 }
 
 
-void 
-HelpSearch(IN OUT SEARCHER_THREAD_CONTEXT *ctx, 
+void
+HelpSearch(IN OUT SEARCHER_THREAD_CONTEXT *ctx,
            IN ULONG u)
 /**
 
@@ -1063,7 +1066,7 @@ Return value:
     SCORE iCheckSee;
 #ifdef DEBUG
     POSITION board;
-    
+
     memcpy(&board, &ctx->sPosition, sizeof(POSITION));
     ASSERT(PositionsAreEquivalent(&board, &g_SplitInfo[u].sSplitPosition));
 #endif
@@ -1072,21 +1075,24 @@ Return value:
     iBeta = g_SplitInfo[u].iBeta;
     uOrigDepth = g_SplitInfo[u].uDepth;
     ctx->sSearchFlags = g_SplitInfo[u].sSearchFlags;
+    SCORE iEval = g_SplitInfo[u].iEval;
+    SCORE iImprovement = g_SplitInfo[u].iImprovement;
+
     do
     {
         iExtend = iOrigExtend;
         uDepth = uOrigDepth;
         ASSERT(ctx->uPly == g_SplitInfo[u].uSplitPly);
-        
+
         mv = _GetNextParallelMove(&iAlpha,
-                                  &iBestScore, 
+                                  &iBestScore,
                                   &uMoveNum,
                                   u);
         if (mv.uMove == 0) break;              // Split is terminating
 
         ASSERT(IS_VALID_SCORE(iBestScore));
         ASSERT(uMoveNum < MAX_MOVES_PER_PLY);
-        ASSERT(IS_SAME_MOVE(mv, 
+        ASSERT(IS_SAME_MOVE(mv,
           ctx->sMoveStack.mvf[ctx->sMoveStack.uBegin[ctx->uPly]+uMoveNum].mv));
         ASSERT(uDepth <= MAX_DEPTH_PER_SEARCH);
         ASSERT(IS_VALID_SCORE(iAlpha));
@@ -1094,7 +1100,7 @@ Return value:
         ASSERT(iAlpha < iBeta);
         ASSERT(iExtend >= -ONE_PLY);
         ASSERT(iExtend <= +ONE_PLY);
-        
+
         // SEE on the PRE-move position -- see search.c's identical comment.
         iCheckSee = 0;
         if (IS_CHECKING_MOVE(mv))
@@ -1105,25 +1111,21 @@ Return value:
                                         uMoveNum);
         }
 
-        if (MakeMove(ctx, mv))
+        if (TRUE == MakeMove(ctx, mv))
         {
-            ASSERT((IS_CHECKING_MOVE(mv) &&
-                    InCheck(&ctx->sPosition, ctx->sPosition.uToMove)) ||
-                   (!IS_CHECKING_MOVE(mv) &&
-                    !InCheck(&ctx->sPosition, ctx->sPosition.uToMove)));
-            iRoughEval = GetRoughEvalScore(ctx, iAlpha, iBeta, TRUE);
+            ASSERT((IS_CHECKING_MOVE(mv) && InCheck(&ctx->sPosition, ctx->sPosition.uToMove)) ||
+                   (!IS_CHECKING_MOVE(mv) && !InCheck(&ctx->sPosition, ctx->sPosition.uToMove)));
 
             // Compute extension
             ComputeMoveExtension(ctx,
                                  iAlpha,
                                  iBeta,
-                                 (ctx->sMoveStack.uBegin[ctx->uPly - 1] +
-                                  uMoveNum),
-                                 iRoughEval,
+                                 (ctx->sMoveStack.uBegin[ctx->uPly - 1] + uMoveNum),
+                                 iEval,
                                  uDepth,
                                  iCheckSee,
                                  &iExtend);
-            
+
             //
             // Cap total extension plies spent on this line, same as the
             // non-split move loop in search.c does.
@@ -1139,9 +1141,10 @@ Return value:
             // Decide how much (if any) to reduce this move's depth.
             //
             {
-                INT iLMR = GetLMRReduction(iRoughEval,
+                INT iLMR = GetLMRReduction(iEval,
                                            iAlpha,
                                            iBeta,
+                                           iImprovement,
                                            ctx,
                                            uDepth,
                                            (g_SplitInfo[u].uAlreadyDone +