Try hard not to lose on time

[stockfish] / src / thread.cpp

diff --git a/src/thread.cpp b/src/thread.cpp
index 8af9dc414f1c35c1a53f1640cb3bf2a3e5f50cec..cb0ab5e9c258eea998fe9c5892e77e88562308c2 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) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2012 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
@@ -23,6 +23,8 @@
 #include "thread.h"
 #include "ucioption.h"
 
+using namespace Search;
+
 ThreadsManager Threads; // Global object
 
 namespace { extern "C" {
@@ -110,11 +112,11 @@ bool Thread::is_available_to(int master) const {
 
 void ThreadsManager::read_uci_options() {
 
-  maxThreadsPerSplitPoint = Options["Maximum Number of Threads per Split Point"].value<int>();
-  minimumSplitDepth       = Options["Minimum Split Depth"].value<int>() * ONE_PLY;
-  useSleepingThreads      = Options["Use Sleeping Threads"].value<bool>();
+  maxThreadsPerSplitPoint = Options["Max Threads per Split Point"];
+  minimumSplitDepth       = Options["Min Split Depth"] * ONE_PLY;
+  useSleepingThreads      = Options["Use Sleeping Threads"];
 
-  set_size(Options["Threads"].value<int>());
+  set_size(Options["Threads"]);
 }
 
 
@@ -170,14 +172,14 @@ void ThreadsManager::init() {
   for (int i = 0; i <= MAX_THREADS; i++)
   {
       threads[i].is_searching = false;
-      threads[i].do_sleep = true;
+      threads[i].do_sleep = (i != 0); // Avoid a race with start_thinking()
       threads[i].threadID = i;
 
 #if defined(_MSC_VER)
-      threads[i].handle = CreateThread(NULL, 0, start_routine, (LPVOID)&threads[i], 0, NULL);
+      threads[i].handle = CreateThread(NULL, 0, start_routine, &threads[i], 0, NULL);
       bool ok = (threads[i].handle != NULL);
 #else
-      bool ok = !pthread_create(&threads[i].handle, NULL, start_routine, (void*)&threads[i]);
+      bool ok = !pthread_create(&threads[i].handle, NULL, start_routine, &threads[i]);
 #endif
 
       if (!ok)
@@ -195,12 +197,12 @@ void ThreadsManager::exit() {
 
   for (int i = 0; i <= MAX_THREADS; i++)
   {
-      threads[i].do_terminate = true;
+      threads[i].do_terminate = true; // Search must be already finished
       threads[i].wake_up();
 
       // Wait for thread termination
 #if defined(_MSC_VER)
-      WaitForSingleObject(threads[i].handle, 0);
+      WaitForSingleObject(threads[i].handle, INFINITE);
       CloseHandle(threads[i].handle);
 #else
       pthread_join(threads[i].handle, NULL);
@@ -257,11 +259,11 @@ bool ThreadsManager::split_point_finished(SplitPoint* sp) const {
 // search(). When all threads have returned from search() then split() returns.
 
 template <bool Fake>
-Value ThreadsManager::split(Position& pos, SearchStack* ss, Value alpha, Value beta,
+Value ThreadsManager::split(Position& pos, Stack* ss, Value alpha, Value beta,
                             Value bestValue, Depth depth, Move threatMove,
                             int moveCount, MovePicker* mp, int nodeType) {
   assert(pos.pos_is_ok());
-  assert(bestValue >= -VALUE_INFINITE);
+  assert(bestValue > -VALUE_INFINITE);
   assert(bestValue <= alpha);
   assert(alpha < beta);
   assert(beta <= VALUE_INFINITE);
@@ -359,12 +361,13 @@ Value ThreadsManager::split(Position& pos, SearchStack* ss, Value alpha, Value b
 }
 
 // Explicit template instantiations
-template Value ThreadsManager::split<false>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
-template Value ThreadsManager::split<true>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
+template Value ThreadsManager::split<false>(Position&, Stack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
+template Value ThreadsManager::split<true>(Position&, Stack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
 
 
 // Thread::timer_loop() is where the timer thread waits maxPly milliseconds and
 // then calls do_timer_event(). If maxPly is 0 thread sleeps until is woken up.
+extern void check_time();
 
 void Thread::timer_loop() {
 
@@ -373,7 +376,7 @@ void Thread::timer_loop() {
       lock_grab(&sleepLock);
       timed_wait(&sleepCond, &sleepLock, maxPly ? maxPly : INT_MAX);
       lock_release(&sleepLock);
-      do_timer_event();
+      check_time();
   }
 }
 
@@ -417,7 +420,7 @@ void Thread::main_loop() {
       if (do_terminate)
           return;
 
-      Search::think(); // This is the search entry point
+      think(); // This is the search entry point
   }
 }
 
@@ -427,7 +430,7 @@ void Thread::main_loop() {
 // then function returns immediately, otherwise caller is blocked waiting for
 // the search to finish.
 
-void ThreadsManager::start_thinking(const Position& pos, const Search::LimitsType& limits,
+void ThreadsManager::start_thinking(const Position& pos, const LimitsType& limits,
                                     const std::vector<Move>& searchMoves, bool asyncMode) {
   Thread& main = threads[0];
 
@@ -438,17 +441,39 @@ void ThreadsManager::start_thinking(const Position& pos, const Search::LimitsTyp
       cond_wait(&sleepCond, &main.sleepLock);
 
   // Copy input arguments to initialize the search
-  Search::RootPosition.copy(pos, 0);
-  Search::Limits = limits;
-  Search::RootMoves = searchMoves;
+  RootPosition.copy(pos, 0);
+  Limits = limits;
+  SearchMoves = searchMoves;
 
   // Reset signals before to start the new search
-  memset((void*)&Search::Signals, 0, sizeof(Search::Signals));
+  memset((void*)&Signals, 0, sizeof(Signals));
 
   main.do_sleep = false;
   cond_signal(&main.sleepCond); // Wake up main thread and start searching
 
   if (!asyncMode)
+      while (!main.do_sleep)
+          cond_wait(&sleepCond, &main.sleepLock);
+
+  lock_release(&main.sleepLock);
+}
+
+
+// ThreadsManager::stop_thinking() is used by UI thread to raise a stop request
+// and to wait for the main thread finishing the search. Needed to wait exiting
+// and terminate the threads after a 'quit' command.
+
+void ThreadsManager::stop_thinking() {
+
+  Thread& main = threads[0];
+
+  Search::Signals.stop = true;
+
+  lock_grab(&main.sleepLock);
+
+  cond_signal(&main.sleepCond); // In case is waiting for stop or ponderhit
+
+  while (!main.do_sleep)
       cond_wait(&sleepCond, &main.sleepLock);
 
   lock_release(&main.sleepLock);
@@ -464,13 +489,13 @@ void ThreadsManager::start_thinking(const Position& pos, const Search::LimitsTyp
 
 void ThreadsManager::wait_for_stop_or_ponderhit() {
 
-  Search::Signals.stopOnPonderhit = true;
+  Signals.stopOnPonderhit = true;
 
   Thread& main = threads[0];
 
   lock_grab(&main.sleepLock);
 
-  while (!Search::Signals.stop)
+  while (!Signals.stop)
       cond_wait(&main.sleepCond, &main.sleepLock);
 
   lock_release(&main.sleepLock);