Improving for nullmove, eval speedup, remove old cruft, bugfix in split / MP.

1 files changed, 15 insertions, 9 deletions

diff --git a/src/searchsup.c b/src/searchsup.c
index 72667c8..d2cbbbd 100644
--- a/src/searchsup.c
+++ b/src/searchsup.c
@@ -1089,14 +1089,14 @@ SelectNullmoveRFactor(SEARCHER_THREAD_CONTEXT *ctx,
 }
 
 
-FLAG
-WeShouldTryNullmovePruning(SEARCHER_THREAD_CONTEXT *ctx,
-                           SCORE iAlpha,
-                           SCORE iBeta,
-                           SCORE iRoughEval,
-                           ULONG uNullDepth) 
+FLAG WeShouldTryNullmovePruning(SEARCHER_THREAD_CONTEXT *ctx,
+                                SCORE iAlpha,
+                                SCORE iBeta,
+                                SCORE iRoughEval,
+	                            SCORE iImprovement,
+                                ULONG uNullDepth)
 {
-    static SCORE _iDistAlphaSkipNull[] = {
+    static SCORE iSkipNullMargins[] = {
       700, 950, 1110, 1150, 1190, 1230, 1270, 0
     };
     POSITION *pos = &ctx->sPosition;
@@ -1119,8 +1119,14 @@ WeShouldTryNullmovePruning(SEARCHER_THREAD_CONTEXT *ctx,
         {
             u = uNullDepth / ONE_PLY;
             ASSERT(u <= 6);
-            if ((iRoughEval + _iDistAlphaSkipNull[u] <= iAlpha) ||
-                ((iRoughEval + _iDistAlphaSkipNull[u] / 2 <= iAlpha) &&
+            SCORE iMargin = iSkipNullMargins[u];
+            if (iImprovement > 0)
+			{
+                iMargin -= iImprovement;
+				iMargin = MAX(0, iMargin);
+			}
+            if ((iRoughEval + iMargin <= iAlpha) ||
+                ((iRoughEval + iMargin / 2 <= iAlpha) &&
                  (ValueOfMaterialInTroubleAfterNull(ctx, pos->uToMove))))
             {
                 return FALSE;