razor margin extension. Bench: 5400244

vondele · Apr 19, 2017 · 07c44d9 · 07c44d9
1 parent d4b9ee0
commit 07c44d9
Showing 1 changed file with 4 additions and 4 deletions.
diff --git a/src/search.cpp b/src/search.cpp
@@ -68,7 +68,7 @@ namespace {
   const int skipPhase[] = { 0, 1, 0, 1, 2, 3, 0, 1, 2, 3, 4, 5, 0, 1, 2, 3, 4, 5, 6, 7 };
 
   // Razoring and futility margin based on depth
-  const int razor_margin[4] = { 483, 570, 603, 554 };
+  Value razor_margin(Depth d)    { return Value(600 - 2 * Eval::Tempo * (1 & d / ONE_PLY)); }
   Value futility_margin(Depth d) { return Value(150 * d / ONE_PLY); }
 
   // Futility and reductions lookup tables, initialized at startup
@@ -708,13 +708,13 @@ namespace {
 
     // Step 6. Razoring (skipped when in check)
     if (   !PvNode
-        &&  depth < 4 * ONE_PLY
-        &&  eval + razor_margin[depth / ONE_PLY] <= alpha)
+        &&  depth < 6 * ONE_PLY
+        &&  eval <= alpha - razor_margin(depth))
     {
         if (depth <= ONE_PLY)
             return qsearch<NonPV, false>(pos, ss, alpha, alpha+1);
 
-        Value ralpha = alpha - razor_margin[depth / ONE_PLY];
+        Value ralpha = alpha - razor_margin(depth);
         Value v = qsearch<NonPV, false>(pos, ss, ralpha, ralpha+1);
         if (v <= ralpha)
             return v;