Allow SearchStack to link an EvalInfo object

This will allow to have wider access to attack
information, for instance from MovePicker.

Note that 'eval' field become obsolete, it is kept
just becasue when we get a position score from TT
we update 'eval' even without an EvalInfo object.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/search.cpp b/src/search.cpp
index d659fab6a1654f6bce5b1ed4d26e120d3962cb3a..403c9363abee5d95ea5589a4d524c92680ec324c 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -653,6 +653,7 @@ void SearchStack::init(int ply) {
   currentMove = threatMove = MOVE_NONE;
   reduction = Depth(0);
   eval = VALUE_NONE;
+  evalInfo = NULL;
 }
 
 void SearchStack::initKillers() {
@@ -1375,14 +1376,15 @@ namespace {
     const int FutilityValueMargin = 112 * bitScanReverse32(int(depth) * int(depth) / 2);
 
     // Evaluate the position statically
-    if (isCheck)
-        ss[ply].eval = VALUE_NONE;
-    else
+    if (!isCheck)
     {
         if (tte && (tte->type() & VALUE_TYPE_EVAL))
             staticValue = value_from_tt(tte->value(), ply);
         else
+        {
             staticValue = evaluate(pos, ei, threadID);
+            ss[ply].evalInfo = &ei;
+        }
 
         ss[ply].eval = staticValue;
         futilityValue = staticValue + FutilityValueMargin;

diff --git a/src/search.h b/src/search.h
index db9bef3c69fec6bed8d21a0386a08972321b7160..7b114bf2126ec4b20639bf8772219c8d2130888b 100644 (file)
--- a/src/search.h
+++ b/src/search.h
@@ -47,6 +47,7 @@ const int KILLER_MAX = 2;
 /// from nodes shallower and deeper in the tree during the search.  Each
 /// search thread has its own array of SearchStack objects, indexed by the
 /// current ply.
+struct EvalInfo;
 
 struct SearchStack {
   Move pv[PLY_MAX_PLUS_2];
@@ -56,6 +57,7 @@ struct SearchStack {
   Move killers[KILLER_MAX];
   Depth reduction;
   Value eval;
+  EvalInfo* evalInfo;
 
   void init(int ply);
   void initKillers();