ceph/src/boost/boost/smart_ptr/detail/sp_thread_pause.hpp

   1 #ifndef BOOST_SMART_PTR_DETAIL_SP_THREAD_PAUSE_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_DETAIL_SP_THREAD_PAUSE_HPP_INCLUDED
   3
   4 // MS compatible compilers support #pragma once
   5
   6 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
   7 # pragma once
   8 #endif
   9
  10 // boost/smart_ptr/detail/sp_thread_pause.hpp
  11 //
  12 // inline void bost::detail::sp_thread_pause();
  13 //
  14 //   Emits a "pause" instruction.
  15 //
  16 // Copyright 2008, 2020 Peter Dimov
  17 // Distributed under the Boost Software License, Version 1.0
  18 // https://www.boost.org/LICENSE_1_0.txt
  19
  20 #if defined(_MSC_VER) && _MSC_VER >= 1310 && ( defined(_M_IX86) || defined(_M_X64) ) && !defined(__c2__)
  21
  22 extern "C" void _mm_pause();
  23
  24 #define BOOST_SP_PAUSE _mm_pause();
  25
  26 #elif defined(__GNUC__) && ( defined(__i386__) || defined(__x86_64__) )
  27
  28 #define BOOST_SP_PAUSE __asm__ __volatile__( "rep; nop" : : : "memory" );
  29
  30 #else
  31
  32 #define BOOST_SP_PAUSE
  33
  34 #endif
  35
  36 namespace boost
  37 {
  38 namespace detail
  39 {
  40
  41 inline void sp_thread_pause()
  42 {
  43     BOOST_SP_PAUSE
  44 }
  45
  46 } // namespace detail
  47 } // namespace boost
  48
  49 #undef BOOST_SP_PAUSE
  50
  51 #endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_THREAD_PAUSE_HPP_INCLUDED