X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=166ea80f65a8af4ec6dca96ada543142873e71c4;hp=ba9197ce4aabe43ab316b02f802f8efcdfc1a89a;hb=775f8239d3bec75c8deaf951ab24d3a030b671ee;hpb=3c07603dac03f0da20194097cf4eb1a396fea60d

diff --git a/src/thread.h b/src/thread.h
index ba9197ce..166ea80f 100644
--- a/src/thread.h
+++ b/src/thread.h
@@ -20,6 +20,7 @@
 #ifndef THREAD_H_INCLUDED
 #define THREAD_H_INCLUDED
 
+#include <atomic>
 #include <bitset>
 #include <condition_variable>
 #include <mutex>
@@ -34,10 +35,9 @@
 
 struct Thread;
 
-const int MAX_THREADS = 128;
-const int MAX_SPLITPOINTS_PER_THREAD = 8;
-
-struct Thread;
+const size_t MAX_THREADS = 128;
+const size_t MAX_SPLITPOINTS_PER_THREAD = 8;
+const size_t MAX_SLAVES_PER_SPLITPOINT = 4;
 
 /// SplitPoint struct stores information shared by the threads searching in
 /// parallel below the same split point. It is populated at splitting time.
@@ -47,7 +47,7 @@ struct SplitPoint {
   // Const data after split point has been setup
   const Position* pos;
   Search::Stack* ss;
-  Thread* masterThread;
+  Thread* master;
   Depth depth;
   Value beta;
   int nodeType;
@@ -70,13 +70,25 @@ struct SplitPoint {
 };
 
 
+/// Spinlock class wraps low level atomic operations to provide spin lock functionality
+
+class Spinlock {
+
+  std::atomic_flag lock;
+
+public:
+  Spinlock() { std::atomic_flag_clear(&lock); }
+  void acquire() { while (lock.test_and_set(std::memory_order_acquire)) {} }
+  void release() { lock.clear(std::memory_order_release); }
+};
+
+
 /// ThreadBase struct is the base of the hierarchy from where we derive all the
 /// specialized thread classes.
 
 struct ThreadBase {
 
-  ThreadBase() : exit(false) {}
-  virtual ~ThreadBase() {}
+  virtual ~ThreadBase() = default;
   virtual void idle_loop() = 0;
   void notify_one();
   void wait_for(volatile const bool& b);
@@ -84,7 +96,7 @@ struct ThreadBase {
   std::thread nativeThread;
   std::mutex mutex;
   std::condition_variable sleepCondition;
-  volatile bool exit;
+  volatile bool exit = false;
 };
 
 
@@ -111,7 +123,7 @@ struct Thread : public ThreadBase {
   size_t idx;
   int maxPly;
   SplitPoint* volatile activeSplitPoint;
-  volatile int splitPointsSize;
+  volatile size_t splitPointsSize;
   volatile bool searching;
 };
 
@@ -120,19 +132,17 @@ struct Thread : public ThreadBase {
 /// special threads: the main one and the recurring timer.
 
 struct MainThread : public Thread {
-  MainThread() : thinking(true) {} // Avoid a race with start_thinking()
   virtual void idle_loop();
-  volatile bool thinking;
+  volatile bool thinking = true; // Avoid a race with start_thinking()
 };
 
 struct TimerThread : public ThreadBase {
 
   static const int Resolution = 5; // Millisec between two check_time() calls
 
-  TimerThread() : run(false) {}
   virtual void idle_loop();
 
-  bool run;
+  bool run = false;
 };