Fix compatibility with old Windows 95 and 98

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 856c003a3654f758f44cc5523264fb84910255d7..e3030490863f4289df4439ce287a4306bc297262 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -136,7 +136,7 @@ void Search::init() {
 
   // Init futility move count array
   for (d = 0; d < 32; d++)
-      FutilityMoveCounts[d] = int(3.001 + 0.25 * pow(d, 2.0));
+      FutilityMoveCounts[d] = int(3.001 + 0.25 * pow(double(d), 2.0));
 }
 
 
@@ -557,6 +557,8 @@ namespace {
             : ttValue >= beta ? (tte->type() & BOUND_LOWER)
                               : (tte->type() & BOUND_UPPER)))
     {
+        assert(ttValue != VALUE_NONE); // Due to depth > DEPTH_NONE
+
         TT.refresh(tte);
         ss->currentMove = ttMove; // Can be MOVE_NONE
 
@@ -574,6 +576,7 @@ namespace {
     // Step 5. Evaluate the position statically and update parent's gain statistics
     if (inCheck)
         ss->eval = ss->evalMargin = refinedValue = VALUE_NONE;
+
     else if (tte)
     {
         assert(tte->static_value() != VALUE_NONE);
@@ -818,6 +821,8 @@ split_point_start: // At split points actual search starts from here
           &&  pos.pl_move_is_legal(move, ci.pinned)
           &&  abs(ttValue) < VALUE_KNOWN_WIN)
       {
+          assert(ttValue != VALUE_NONE);
+
           Value rBeta = ttValue - int(depth);
           ss->excludedMove = move;
           ss->skipNullMove = true;
@@ -1111,6 +1116,8 @@ split_point_start: // At split points actual search starts from here
             : ttValue >= beta ? (tte->type() & BOUND_LOWER)
                               : (tte->type() & BOUND_UPPER)))
     {
+        assert(ttValue != VALUE_NONE); // Due to ttDepth > DEPTH_NONE
+
         ss->currentMove = ttMove; // Can be MOVE_NONE
         return ttValue;
     }
@@ -1368,13 +1375,10 @@ split_point_start: // At split points actual search starts from here
 
   Value value_to_tt(Value v, int ply) {
 
-    if (v >= VALUE_MATE_IN_MAX_PLY)
-      return v + ply;
+    assert(v != VALUE_NONE);
 
-    if (v <= VALUE_MATED_IN_MAX_PLY)
-      return v - ply;
-
-    return v;
+    return  v >= VALUE_MATE_IN_MAX_PLY  ? v + ply
+          : v <= VALUE_MATED_IN_MAX_PLY ? v - ply : v;
   }
 
 
@@ -1384,13 +1388,9 @@ split_point_start: // At split points actual search starts from here
 
   Value value_from_tt(Value v, int ply) {
 
-    if (v >= VALUE_MATE_IN_MAX_PLY)
-      return v - ply;
-
-    if (v <= VALUE_MATED_IN_MAX_PLY)
-      return v + ply;
-
-    return v;
+    return  v == VALUE_NONE             ? VALUE_NONE
+          : v >= VALUE_MATE_IN_MAX_PLY  ? v - ply
+          : v <= VALUE_MATED_IN_MAX_PLY ? v + ply : v;
   }
 
 
@@ -1435,11 +1435,13 @@ split_point_start: // At split points actual search starts from here
 
 
   // refine_eval() returns the transposition table score if possible, otherwise
-  // falls back on static position evaluation.
+  // falls back on static position evaluation. Note that we never return VALUE_NONE
+  // even if v == VALUE_NONE.
 
   Value refine_eval(const TTEntry* tte, Value v, Value defaultEval) {
 
       assert(tte);
+      assert(v != VALUE_NONE || !tte->type());
 
       if (   ((tte->type() & BOUND_LOWER) && v >= defaultEval)
           || ((tte->type() & BOUND_UPPER) && v < defaultEval))