Microptimize MoveList loop

[stockfish] / src / thread.cpp

diff --git a/src/thread.cpp b/src/thread.cpp
index 80765cdeba0a981e2bbe21120e1694f355c5040c..782cf1acc0dd5153fb8ba3bebad8cf69bc35da12 100644 (file)
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -19,7 +19,6 @@
 
 #include <algorithm> // For std::count
 #include <cassert>
-#include <cstring> // For memset
 #include <iostream>
 
 #include "movegen.h"
@@ -49,6 +48,7 @@ Thread::Thread() /* : splitPoints() */ { // Value-initialization bug in MSVC
   searching = exit = false;
   maxPly = splitPointsSize = 0;
   activeSplitPoint = NULL;
+  activePosition = NULL;
   idx = Threads.size();
 
   if (!thread_create(handle, start_routine, this))
@@ -281,8 +281,6 @@ void Thread::split(Position& pos, Stack* ss, Value alpha, Value beta, Value* bes
   sp.cutoff = false;
   sp.ss = ss;
 
-  memset(sp.slavesPositions, 0, sizeof(sp.slavesPositions));
-
   // Try to allocate available threads and ask them to start searching setting
   // 'searching' flag. This must be done under lock protection to avoid concurrent
   // allocation of the same slave by another master.
@@ -291,6 +289,7 @@ void Thread::split(Position& pos, Stack* ss, Value alpha, Value beta, Value* bes
 
   splitPointsSize++;
   activeSplitPoint = &sp;
+  activePosition = NULL;
 
   size_t slavesCnt = 1; // This thread is always included
   Thread* slave;
@@ -304,31 +303,33 @@ void Thread::split(Position& pos, Stack* ss, Value alpha, Value beta, Value* bes
       slave->notify_one(); // Could be sleeping
   }
 
-  sp.mutex.unlock();
-  Threads.mutex.unlock();
-
   // Everything is set up. The master thread enters the idle loop, from which
   // it will instantly launch a search, because its 'searching' flag is set.
   // The thread will return from the idle loop when all slaves have finished
   // their work at this split point.
   if (slavesCnt > 1 || Fake)
   {
+      sp.mutex.unlock();
+      Threads.mutex.unlock();
+
       Thread::idle_loop(); // Force a call to base class idle_loop()
 
       // In helpful master concept a master can help only a sub-tree of its split
       // point, and because here is all finished is not possible master is booked.
       assert(!searching);
-  }
+      assert(!activePosition);
 
-  // We have returned from the idle loop, which means that all threads are
-  // finished. Note that setting 'searching' and decreasing splitPointsSize is
-  // done under lock protection to avoid a race with Thread::is_available_to().
-  Threads.mutex.lock();
-  sp.mutex.lock();
+      // We have returned from the idle loop, which means that all threads are
+      // finished. Note that setting 'searching' and decreasing splitPointsSize is
+      // done under lock protection to avoid a race with Thread::is_available_to().
+      Threads.mutex.lock();
+      sp.mutex.lock();
+  }
 
   searching = true;
   splitPointsSize--;
   activeSplitPoint = sp.parentSplitPoint;
+  activePosition = &pos;
   pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
   *bestMove = sp.bestMove;
   *bestValue = sp.bestValue;
@@ -370,10 +371,10 @@ void ThreadPool::start_thinking(const Position& pos, const LimitsType& limits,
   SetupStates = states; // Ownership transfer here
   RootMoves.clear();
 
-  for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
+  for (MoveList<LEGAL> it(pos); *it; ++it)
       if (   searchMoves.empty()
-          || std::count(searchMoves.begin(), searchMoves.end(), ml.move()))
-          RootMoves.push_back(RootMove(ml.move()));
+          || std::count(searchMoves.begin(), searchMoves.end(), *it))
+          RootMoves.push_back(RootMove(*it));
 
   main_thread()->thinking = true;
   main_thread()->notify_one(); // Starts main thread