X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.cpp;h=1aa66a816619549c60f76f38cf8b030e0828a48d;hp=d095aefeb6a6f875746a67ab68d782e32d031e28;hb=27b593a94477a821f80a041320683f805114d4a3;hpb=e385f194e970f0675bd4c3509bca4a6c81b6df5e

diff --git a/src/thread.cpp b/src/thread.cpp
index d095aefe..1aa66a81 100644
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -1,8 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,24 +16,25 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <algorithm> // For std::count
 #include <cassert>
 
+#include <algorithm> // For std::count
 #include "movegen.h"
 #include "search.h"
 #include "thread.h"
+#include "uci.h"
 #include "syzygy/tbprobe.h"
+#include "tt.h"
 
 ThreadPool Threads; // Global object
 
 
 /// Thread constructor launches the thread and waits until it goes to sleep
-/// in idle_loop(). Note that 'searching' and 'exit' should be alredy set.
+/// in idle_loop(). Note that 'searching' and 'exit' should be already set.
 
 Thread::Thread(size_t n) : idx(n), stdThread(&Thread::idle_loop, this) {
 
   wait_for_search_finished();
-  clear(); // Zero-init histories (based on std::array)
 }
 
 
@@ -52,25 +51,42 @@ Thread::~Thread() {
 }
 
 
+/// Thread::bestMoveCount(Move move) return best move counter for the given root move
+
+int Thread::best_move_count(Move move) const {
+
+  auto rm = std::find(rootMoves.begin() + pvIdx,
+                      rootMoves.begin() + pvLast, move);
+
+  return rm != rootMoves.begin() + pvLast ? rm->bestMoveCount : 0;
+}
+
+
 /// Thread::clear() reset histories, usually before a new game
 
 void Thread::clear() {
 
   counterMoves.fill(MOVE_NONE);
   mainHistory.fill(0);
-
-  for (auto& to : contHistory)
-      for (auto& h : to)
-          h.fill(0);
-
-  contHistory[NO_PIECE][0].fill(Search::CounterMovePruneThreshold - 1);
+  lowPlyHistory.fill(0);
+  captureHistory.fill(0);
+
+  for (bool inCheck : { false, true })
+      for (StatsType c : { NoCaptures, Captures })
+      {
+          for (auto& to : continuationHistory[inCheck][c])
+                for (auto& h : to)
+                      h->fill(0);
+          continuationHistory[inCheck][c][NO_PIECE][0]->fill(Search::CounterMovePruneThreshold - 1);
+      }
 }
 
+
 /// Thread::start_searching() wakes up the thread that will start the search
 
 void Thread::start_searching() {
 
-  std::lock_guard<Mutex> lk(mutex);
+  std::lock_guard<std::mutex> lk(mutex);
   searching = true;
   cv.notify_one(); // Wake up the thread in idle_loop()
 }
@@ -81,7 +97,7 @@ void Thread::start_searching() {
 
 void Thread::wait_for_search_finished() {
 
-  std::unique_lock<Mutex> lk(mutex);
+  std::unique_lock<std::mutex> lk(mutex);
   cv.wait(lk, [&]{ return !searching; });
 }
 
@@ -91,11 +107,17 @@ void Thread::wait_for_search_finished() {
 
 void Thread::idle_loop() {
 
-  WinProcGroup::bindThisThread(idx);
+  // If OS already scheduled us on a different group than 0 then don't overwrite
+  // the choice, eventually we are one of many one-threaded processes running on
+  // some Windows NUMA hardware, for instance in fishtest. To make it simple,
+  // just check if running threads are below a threshold, in this case all this
+  // NUMA machinery is not needed.
+  if (Options["Threads"] > 8)
+      WinProcGroup::bindThisThread(idx);
 
   while (true)
   {
-      std::unique_lock<Mutex> lk(mutex);
+      std::unique_lock<std::mutex> lk(mutex);
       searching = false;
       cv.notify_one(); // Wake up anyone waiting for search finished
       cv.wait(lk, [&]{ return searching; });
@@ -109,39 +131,45 @@ void Thread::idle_loop() {
   }
 }
 
+/// ThreadPool::set() creates/destroys threads to match the requested number.
+/// Created and launched threads will immediately go to sleep in idle_loop.
+/// Upon resizing, threads are recreated to allow for binding if necessary.
 
-/// ThreadPool::init() creates and launches the threads that will go
-/// immediately to sleep in idle_loop. We cannot use the c'tor because
-/// Threads is a static object and we need a fully initialized engine at
-/// this point due to allocation of Endgames in the Thread constructor.
+void ThreadPool::set(size_t requested) {
 
-void ThreadPool::init(size_t requested) {
+  if (size() > 0) { // destroy any existing thread(s)
+      main()->wait_for_search_finished();
 
-  push_back(new MainThread(0));
-  set(requested);
-}
+      while (size() > 0)
+          delete back(), pop_back();
+  }
 
+  if (requested > 0) { // create new thread(s)
+      push_back(new MainThread(0));
 
-/// ThreadPool::exit() terminates threads before the program exits. Cannot be
-/// done in the destructor because threads must be terminated before deleting
-/// any static object, so before main() returns.
+      while (size() < requested)
+          push_back(new Thread(size()));
+      clear();
 
-void ThreadPool::exit() {
+      // Reallocate the hash with the new threadpool size
+      TT.resize(size_t(Options["Hash"]));
 
-  main()->wait_for_search_finished();
-  set(0);
+      // Init thread number dependent search params.
+      Search::init();
+  }
 }
 
 
-/// ThreadPool::set() creates/destroys threads to match the requested number
+/// ThreadPool::clear() sets threadPool data to initial values
 
-void ThreadPool::set(size_t requested) {
+void ThreadPool::clear() {
 
-  while (size() < requested)
-      push_back(new Thread(size()));
+  for (Thread* th : *this)
+      th->clear();
 
-  while (size() > requested)
-      delete back(), pop_back();
+  main()->callsCnt = 0;
+  main()->bestPreviousScore = VALUE_INFINITE;
+  main()->previousTimeReduction = 1.0;
 }
 
 
@@ -153,8 +181,9 @@ void ThreadPool::start_thinking(Position& pos, StateListPtr& states,
 
   main()->wait_for_search_finished();
 
-  stopOnPonderhit = stop = false;
-  ponder = ponderMode;
+  main()->stopOnPonderhit = stop = false;
+  increaseDepth = true;
+  main()->ponder = ponderMode;
   Search::Limits = limits;
   Search::RootMoves rootMoves;
 
@@ -164,7 +193,7 @@ void ThreadPool::start_thinking(Position& pos, StateListPtr& states,
           rootMoves.emplace_back(m);
 
   if (!rootMoves.empty())
-      Tablebases::filter_root_moves(pos, rootMoves);
+      Tablebases::rank_root_moves(pos, rootMoves);
 
   // After ownership transfer 'states' becomes empty, so if we stop the search
   // and call 'go' again without setting a new position states.get() == NULL.
@@ -175,20 +204,68 @@ void ThreadPool::start_thinking(Position& pos, StateListPtr& states,
 
   // We use Position::set() to set root position across threads. But there are
   // some StateInfo fields (previous, pliesFromNull, capturedPiece) that cannot
-  // be deduced from a fen string, so set() clears them and to not lose the info
-  // we need to backup and later restore setupStates->back(). Note that setupStates
-  // is shared by threads but is accessed in read-only mode.
-  StateInfo tmp = setupStates->back();
-
-  for (Thread* th : Threads)
+  // be deduced from a fen string, so set() clears them and they are set from
+  // setupStates->back() later. The rootState is per thread, earlier states are shared
+  // since they are read-only.
+  for (Thread* th : *this)
   {
-      th->nodes = th->tbHits = 0;
-      th->rootDepth = th->completedDepth = DEPTH_ZERO;
+      th->nodes = th->tbHits = th->nmpMinPly = th->bestMoveChanges = 0;
+      th->rootDepth = th->completedDepth = 0;
       th->rootMoves = rootMoves;
-      th->rootPos.set(pos.fen(), pos.is_chess960(), &setupStates->back(), th);
+      th->rootPos.set(pos.fen(), pos.is_chess960(), &th->rootState, th);
+      th->rootState = setupStates->back();
   }
 
-  setupStates->back() = tmp;
-
   main()->start_searching();
 }
+
+Thread* ThreadPool::get_best_thread() const {
+
+    Thread* bestThread = front();
+    std::map<Move, int64_t> votes;
+    Value minScore = VALUE_NONE;
+
+    // Find minimum score of all threads
+    for (Thread* th: *this)
+        minScore = std::min(minScore, th->rootMoves[0].score);
+
+    // Vote according to score and depth, and select the best thread
+    for (Thread* th : *this)
+    {
+        votes[th->rootMoves[0].pv[0]] +=
+            (th->rootMoves[0].score - minScore + 14) * int(th->completedDepth);
+
+          if (abs(bestThread->rootMoves[0].score) >= VALUE_TB_WIN_IN_MAX_PLY)
+          {
+              // Make sure we pick the shortest mate / TB conversion or stave off mate the longest
+              if (th->rootMoves[0].score > bestThread->rootMoves[0].score)
+                  bestThread = th;
+          }
+          else if (   th->rootMoves[0].score >= VALUE_TB_WIN_IN_MAX_PLY
+                   || (   th->rootMoves[0].score > VALUE_TB_LOSS_IN_MAX_PLY
+                       && votes[th->rootMoves[0].pv[0]] > votes[bestThread->rootMoves[0].pv[0]]))
+              bestThread = th;
+    }
+
+    return bestThread;
+}
+
+
+/// Start non-main threads
+
+void ThreadPool::start_searching() {
+
+    for (Thread* th : *this)
+        if (th != front())
+            th->start_searching();
+}
+
+
+/// Wait for non-main threads
+
+void ThreadPool::wait_for_search_finished() const {
+
+    for (Thread* th : *this)
+        if (th != front())
+            th->wait_for_search_finished();
+}