Initial Commit - Lesson 31 (Commit #1)

Plugins/GameLiftServerSDK/ThirdParty/concurrentqueue/benchmarks/tbb/scheduler_utility.h

@@ -0,0 +1,133 @@
+/*
+    Copyright 2005-2014 Intel Corporation.  All Rights Reserved.
+
+    This file is part of Threading Building Blocks. Threading Building Blocks is free software;
+    you can redistribute it and/or modify it under the terms of the GNU General Public License
+    version 2  as  published  by  the  Free Software Foundation.  Threading Building Blocks is
+    distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
+    implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+    See  the GNU General Public License for more details.   You should have received a copy of
+    the  GNU General Public License along with Threading Building Blocks; if not, write to the
+    Free Software Foundation, Inc.,  51 Franklin St,  Fifth Floor,  Boston,  MA 02110-1301 USA
+
+    As a special exception,  you may use this file  as part of a free software library without
+    restriction.  Specifically,  if other files instantiate templates  or use macros or inline
+    functions from this file, or you compile this file and link it with other files to produce
+    an executable,  this file does not by itself cause the resulting executable to be covered
+    by the GNU General Public License. This exception does not however invalidate any other
+    reasons why the executable file might be covered by the GNU General Public License.
+*/
+
+#ifndef _TBB_scheduler_utility_H
+#define _TBB_scheduler_utility_H
+
+#include "scheduler.h"
+
+namespace tbb {
+namespace internal {
+
+//------------------------------------------------------------------------
+// auto_empty_task
+//------------------------------------------------------------------------
+
+//! Smart holder for the empty task class with automatic destruction
+class auto_empty_task {
+    task* my_task;
+    generic_scheduler* my_scheduler;
+public:
+    auto_empty_task ( __TBB_CONTEXT_ARG(generic_scheduler *s, task_group_context* context) ) 
+        : my_task( new(&s->allocate_task(sizeof(empty_task), __TBB_CONTEXT_ARG(NULL, context))) empty_task )
+        , my_scheduler(s)
+    {}
+    // empty_task has trivial destructor, so there's no need to call it.
+    ~auto_empty_task () { my_scheduler->free_task<small_local_task>(*my_task); }
+
+    operator task& () { return *my_task; }
+    task* operator & () { return my_task; }
+    task_prefix& prefix () { return my_task->prefix(); }
+}; // class auto_empty_task
+
+//------------------------------------------------------------------------
+// fast_reverse_vector
+//------------------------------------------------------------------------
+
+//! Vector that grows without reallocations, and stores items in the reverse order.
+/** Requires to initialize its first segment with a preallocated memory chunk
+    (usually it is static array or an array allocated on the stack).
+    The second template parameter specifies maximal number of segments. Each next 
+    segment is twice as large as the previous one. **/
+template<typename T, size_t max_segments = 16>
+class fast_reverse_vector
+{
+public:
+    fast_reverse_vector ( T* initial_segment, size_t segment_size )
+        : m_cur_segment(initial_segment)
+        , m_cur_segment_size(segment_size)
+        , m_pos(segment_size)
+        , m_num_segments(0)
+        , m_size(0)
+    {
+        __TBB_ASSERT ( initial_segment && segment_size, "Nonempty initial segment must be supplied");
+    }
+
+    ~fast_reverse_vector ()
+    {
+        for ( size_t i = 1; i < m_num_segments; ++i )
+            NFS_Free( m_segments[i] );
+    }
+
+    size_t size () const { return m_size + m_cur_segment_size - m_pos; }
+
+    void push_back ( const T& val )
+    {
+        if ( !m_pos ) {
+            if ( !m_num_segments ) m_segments[m_num_segments++] = m_cur_segment;
+            m_size += m_cur_segment_size;
+            m_cur_segment_size *= 2;
+            m_pos = m_cur_segment_size;
+            m_segments[m_num_segments++] = m_cur_segment = (T*)NFS_Allocate( m_cur_segment_size, sizeof(T), NULL );
+            __TBB_ASSERT ( m_num_segments < max_segments, "Maximal capacity exceeded" );
+        }
+        m_cur_segment[--m_pos] = val;
+    }
+
+    //! Copies the contents of the vector into the dst array. 
+    /** Can only be used when T is a POD type, as copying does not invoke copy constructors. **/
+    void copy_memory ( T* dst ) const
+    {
+        size_t sz = m_cur_segment_size - m_pos;
+        memcpy( dst, m_cur_segment + m_pos, sz * sizeof(T) );
+        dst += sz;
+        sz = m_cur_segment_size / 2;
+        for ( long i = (long)m_num_segments - 2; i >= 0; --i ) {
+            memcpy( dst, m_segments[i], sz * sizeof(T) );
+            dst += sz;
+            sz /= 2;
+        }
+    }
+
+protected:
+    //! The current (not completely filled) segment
+    T       *m_cur_segment;
+
+    //! Capacity of m_cur_segment
+    size_t  m_cur_segment_size;
+
+    //! Insertion position in m_cur_segment
+    size_t  m_pos;
+
+    //! Array of segments (has fixed size specified by the second template parameter)
+    T       *m_segments[max_segments];
+    
+    //! Number of segments (the size of m_segments)
+    size_t  m_num_segments;
+
+    //! Number of items in the segments in m_segments
+    size_t  m_size;
+
+}; // class fast_reverse_vector
+
+} // namespace internal
+} // namespace tbb
+
+#endif /* _TBB_scheduler_utility_H */