Sync sp_search() with search()

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index bd482eaeb769d1a63f6e55c17903e29c797c38bb..6ec744c859596415703fa8bef8e520f7eba47879 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -52,9 +52,6 @@ using std::endl;
 
 namespace {
 
-  // Maximum number of allowed moves per position
-  const int MOVES_MAX = 256;
-
   // Types
   enum NodeType { NonPV, PV };
 
@@ -366,7 +363,7 @@ void init_search() {
 
   // Init futility move count array
   for (d = 0; d < 32; d++)
-      FutilityMoveCountArray[d] = 3 + (1 << (3 * d / 8));
+      FutilityMoveCountArray[d] = int(3.001 + 0.25 * pow(d, 2.0));
 }
 
 
@@ -633,7 +630,7 @@ namespace {
 
             // Add some extra time if the best move has changed during the last two iterations
             if (Iteration > 5 && Iteration <= 50)
-                TimeMgr.pv_unstability(BestMoveChangesByIteration[Iteration],
+                TimeMgr.pv_instability(BestMoveChangesByIteration[Iteration],
                                        BestMoveChangesByIteration[Iteration-1]);
 
             // Stop search if most of MaxSearchTime is consumed at the end of the
@@ -997,7 +994,7 @@ namespace {
 
     // Step 2. Check for aborted search and immediate draw
     if (AbortSearch || ThreadsMgr.thread_should_stop(threadID))
-        return VALUE_ZERO;
+        return VALUE_DRAW;
 
     if (pos.is_draw() || ply >= PLY_MAX - 1)
         return VALUE_DRAW;
@@ -1695,13 +1692,12 @@ namespace {
       if (value > sp->bestValue && !ThreadsMgr.thread_should_stop(threadID))
       {
           sp->bestValue = value;
-
-          if (sp->bestValue > sp->alpha)
+          if (value > sp->alpha)
           {
               if (!PvNode || value >= sp->beta)
                   sp->stopRequest = true;
 
-              if (PvNode && value < sp->beta) // This guarantees that always: sp->alpha < sp->beta
+              if (PvNode && value < sp->beta) // We want always sp->alpha < sp->beta
                   sp->alpha = value;
 
               sp->parentSstack->bestMove = ss->bestMove = move;
@@ -2387,6 +2383,8 @@ namespace {
             lock_grab(&(sp->lock));
             lock_release(&(sp->lock));
 
+            // In helpful master concept a master can help only a sub-tree, and
+            // because here is all finished is not possible master is booked.
             assert(threads[threadID].state == THREAD_AVAILABLE);
 
             threads[threadID].state = THREAD_SEARCHING;
@@ -2464,13 +2462,11 @@ namespace {
 
   void ThreadsManager::exit_threads() {
 
-    ActiveThreads = MAX_THREADS;  // HACK
-    AllThreadsShouldSleep = true;  // HACK
+    ActiveThreads = MAX_THREADS;  // Wake up all the threads
+    AllThreadsShouldExit = true;  // Let the woken up threads to exit idle_loop()
+    AllThreadsShouldSleep = true; // Avoid an assert in wake_sleeping_threads()
     wake_sleeping_threads();
 
-    // This makes the threads to exit idle_loop()
-    AllThreadsShouldExit = true;
-
     // Wait for thread termination
     for (int i = 1; i < MAX_THREADS; i++)
         while (threads[i].state != THREAD_TERMINATED) {}
@@ -2493,9 +2489,9 @@ namespace {
 
     assert(threadID >= 0 && threadID < ActiveThreads);
 
-    SplitPoint* sp;
+    SplitPoint* sp = threads[threadID].splitPoint;
 
-    for (sp = threads[threadID].splitPoint; sp && !sp->stopRequest; sp = sp->parent) {}
+    for ( ; sp && !sp->stopRequest; sp = sp->parent) {}
     return sp != NULL;
   }
 
@@ -2520,12 +2516,9 @@ namespace {
     // Make a local copy to be sure doesn't change under our feet
     int localActiveSplitPoints = threads[slave].activeSplitPoints;
 
-    if (localActiveSplitPoints == 0)
-        // No active split points means that the thread is available as
-        // a slave for any other thread.
-        return true;
-
-    if (ActiveThreads == 2)
+    // No active split points means that the thread is available as
+    // a slave for any other thread.
+    if (localActiveSplitPoints == 0 || ActiveThreads == 2)
         return true;
 
     // Apply the "helpful master" concept if possible. Use localActiveSplitPoints