X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=1bf56c8ea59a4ea8190f3e58b182c1ace6610a9e;hp=b269962f9558f006899b5aca06d8973b1153e1c6;hb=5bb9da92872f298e6aedb59d728a42dc5719738e;hpb=fc234662364386800ec728643d7d6da610a560aa

diff --git a/src/search.cpp b/src/search.cpp
index b269962f..1bf56c8e 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -171,6 +171,9 @@ namespace {
   // evaluation of the position is more than NullMoveMargin below beta.
   const Value NullMoveMargin = Value(0x200);
 
+  // Depth limit for use of dynamic threat detection when null move fails low
+  const Depth ThreatDepth = 5 * OnePly;
+
   // Step 9. Internal iterative deepening
 
   const Depth IIDDepthAtPVNodes = 5 * OnePly;
@@ -195,36 +198,36 @@ namespace {
   // remaining ones we will extend it.
   const Value SingularExtensionMargin = Value(0x20);
 
+  // Step 12. Futility pruning
 
+  const Value FutilityMarginQS = Value(0x80);
 
-  // Search depth at iteration 1
-  const Depth InitialDepth = OnePly;
+  // Futility lookup tables (initialized at startup) and their getter functions
+  int32_t FutilityMarginsMatrix[14][64]; // [depth][moveNumber]
+  int FutilityMoveCountArray[32]; // [depth]
 
-  // Easy move margin. An easy move candidate must be at least this much
-  // better than the second best move.
-  const Value EasyMoveMargin = Value(0x200);
+  inline Value futility_margin(Depth d, int mn) { return Value(d < 7*OnePly ? FutilityMarginsMatrix[Max(d, 0)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
+  inline int futility_move_count(Depth d) { return d < 16*OnePly ? FutilityMoveCountArray[d] : 512; }
 
-  /// Lookup tables initialized at startup
+  // Step 14. Reduced search
 
-  // Reduction lookup tables and their getter functions
+  // Reduction lookup tables (initialized at startup) and their getter functions
   int8_t    PVReductionMatrix[64][64]; // [depth][moveNumber]
   int8_t NonPVReductionMatrix[64][64]; // [depth][moveNumber]
 
   inline Depth    pv_reduction(Depth d, int mn) { return (Depth)    PVReductionMatrix[Min(d / 2, 63)][Min(mn, 63)]; }
   inline Depth nonpv_reduction(Depth d, int mn) { return (Depth) NonPVReductionMatrix[Min(d / 2, 63)][Min(mn, 63)]; }
 
-  // Futility lookup tables and their getter functions
-  const Value FutilityMarginQS = Value(0x80);
-  int32_t FutilityMarginsMatrix[14][64]; // [depth][moveNumber]
-  int FutilityMoveCountArray[32]; // [depth]
 
-  inline Value futility_margin(Depth d, int mn) { return Value(d < 7*OnePly ? FutilityMarginsMatrix[Max(d, 0)][Min(mn, 63)] : 2 * VALUE_INFINITE); }
-  inline int futility_move_count(Depth d) { return d < 16*OnePly ? FutilityMoveCountArray[d] : 512; }
 
-  /// Variables initialized by UCI options
+  // Search depth at iteration 1
+  const Depth InitialDepth = OnePly;
 
-  // Depth limit for use of dynamic threat detection
-  Depth ThreatDepth;
+  // Easy move margin. An easy move candidate must be at least this much
+  // better than the second best move.
+  const Value EasyMoveMargin = Value(0x200);
+
+  /// Variables initialized by UCI options
 
   // Last seconds noise filtering (LSN)
   const bool UseLSNFiltering = true;
@@ -426,8 +429,6 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
   MateThreatExtension[1] = Depth(get_option_value_int("Mate Threat Extension (PV nodes)"));
   MateThreatExtension[0] = Depth(get_option_value_int("Mate Threat Extension (non-PV nodes)"));
 
-  ThreatDepth   = get_option_value_int("Threat Depth") * OnePly;
-
   Chess960 = get_option_value_bool("UCI_Chess960");
   ShowCurrentLine = get_option_value_bool("UCI_ShowCurrLine");
   UseLogFile = get_option_value_bool("Use Search Log");
@@ -1492,7 +1493,7 @@ namespace {
               continue;
 
           // Value based pruning
-          Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); //FIXME: We are ignoring condition: depth >= 3*OnePly, BUG??
+          Depth predictedDepth = newDepth - nonpv_reduction(depth, moveCount); // We illogically ignore reduction condition depth >= 3*OnePly
           futilityValueScaled =  ss[ply].eval + futility_margin(predictedDepth, moveCount)
                                + H.gain(pos.piece_on(move_from(move)), move_to(move)) + 45;