Small lnArray[] cleanup

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index d659fab6a1654f6bce5b1ed4d26e120d3962cb3a..2c4d5ece2eb237f861890d7ac4add6c1c8c273ed 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -23,6 +23,7 @@
 ////
 
 #include <cassert>
+#include <cmath>
 #include <cstring>
 #include <fstream>
 #include <iostream>
@@ -235,6 +236,10 @@ namespace {
   bool UseLogFile;
   std::ofstream LogFile;
 
+  // Natural logarithmic lookup table and its getter function
+  double lnArray[512];
+  inline double ln(int i) { return lnArray[i]; }
+
   // MP related variables
   int ActiveThreads = 1;
   Depth MinimumSplitDepth;
@@ -319,13 +324,6 @@ namespace {
 //// Functions
 ////
 
-//FIXME: HACK
-static double lnArray[512];
-
-inline double ln(int i)
-{
-    return lnArray[i];
-}
 
 /// perft() is our utility to verify move generation is bug free. All the legal
 /// moves up to given depth are generated and counted and the sum returned.
@@ -559,20 +557,18 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
 /// and initializes the split point stack and the global locks and condition
 /// objects.
 
-#include <cmath> //FIXME: HACK
-
 void init_threads() {
 
-  // FIXME: HACK!!
-  for (int i = 0; i < 512; i++)
-    lnArray[i] = log(double(i));
-
   volatile int i;
 
 #if !defined(_MSC_VER)
   pthread_t pthread[1];
 #endif
 
+  // Init our logarithmic lookup table
+  for (int i = 0; i < 512; i++)
+      lnArray[i] = log(double(i)); // log() returns base-e logarithm
+
   for (i = 0; i < THREAD_MAX; i++)
       Threads[i].activeSplitPoints = 0;
 
@@ -653,6 +649,7 @@ void SearchStack::init(int ply) {
   currentMove = threatMove = MOVE_NONE;
   reduction = Depth(0);
   eval = VALUE_NONE;
+  evalInfo = NULL;
 }
 
 void SearchStack::initKillers() {
@@ -886,7 +883,7 @@ namespace {
   Value root_search(Position& pos, SearchStack ss[], RootMoveList& rml, Value alpha, Value beta) {
 
     Value oldAlpha = alpha;
-    Value value;
+    Value value = -VALUE_INFINITE;
     CheckInfo ci(pos);
 
     // Loop through all the moves in the root move list
@@ -1105,7 +1102,7 @@ namespace {
     Value oldAlpha, value;
     bool isCheck, mateThreat, singleEvasion, moveIsCheck, captureOrPromotion, dangerous;
     int moveCount = 0;
-    Value bestValue = -VALUE_INFINITE;
+    Value bestValue = value = -VALUE_INFINITE;
 
     if (depth < OnePly)
         return qsearch(pos, ss, alpha, beta, Depth(0), ply, threadID);
@@ -1331,7 +1328,7 @@ namespace {
     bool isCheck, useFutilityPruning, singleEvasion, moveIsCheck, captureOrPromotion, dangerous;
     bool mateThreat = false;
     int moveCount = 0;
-    futilityValue = staticValue = bestValue = -VALUE_INFINITE;
+    futilityValue = staticValue = bestValue = value = -VALUE_INFINITE;
 
     if (depth < OnePly)
         return qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID);
@@ -1375,14 +1372,15 @@ 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;
@@ -1455,7 +1453,7 @@ namespace {
 
     // Go with internal iterative deepening if we don't have a TT move
     if (UseIIDAtNonPVNodes && ttMove == MOVE_NONE && depth >= 8*OnePly &&
-        !isCheck && evaluate(pos, ei, threadID) >= beta - IIDMargin)
+        !isCheck && ss[ply].eval >= beta - IIDMargin)
     {
         search(pos, ss, beta, Min(depth/2, depth-2*OnePly), ply, false, threadID);
         ttMove = ss[ply].pv[ply];
@@ -1808,7 +1806,7 @@ namespace {
     Position pos = Position(sp->pos);
     CheckInfo ci(pos);
     SearchStack* ss = sp->sstack[threadID];
-    Value value;
+    Value value = -VALUE_INFINITE;
     Move move;
     bool isCheck = pos.is_check();
     bool useFutilityPruning =     sp->depth < SelectiveDepth
@@ -1950,7 +1948,7 @@ namespace {
     Position pos = Position(sp->pos);
     CheckInfo ci(pos);
     SearchStack* ss = sp->sstack[threadID];
-    Value value;
+    Value value = -VALUE_INFINITE;
     Move move;
 
     while (    sp->alpha < sp->beta