Chris@16: //
Chris@16: // detail/gcc_x86_fenced_block.hpp
Chris@16: // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Chris@16: //
Chris@101: // Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com)
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: 
Chris@16: #ifndef BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
Chris@16: #define BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: # pragma once
Chris@16: #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
Chris@16: 
Chris@16: #include <boost/asio/detail/config.hpp>
Chris@16: 
Chris@16: #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
Chris@16: 
Chris@16: #include <boost/asio/detail/push_options.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace asio {
Chris@16: namespace detail {
Chris@16: 
Chris@16: class gcc_x86_fenced_block
Chris@16:   : private noncopyable
Chris@16: {
Chris@16: public:
Chris@16:   enum half_t { half };
Chris@16:   enum full_t { full };
Chris@16: 
Chris@16:   // Constructor for a half fenced block.
Chris@16:   explicit gcc_x86_fenced_block(half_t)
Chris@16:   {
Chris@16:   }
Chris@16: 
Chris@16:   // Constructor for a full fenced block.
Chris@16:   explicit gcc_x86_fenced_block(full_t)
Chris@16:   {
Chris@16:     lbarrier();
Chris@16:   }
Chris@16: 
Chris@16:   // Destructor.
Chris@16:   ~gcc_x86_fenced_block()
Chris@16:   {
Chris@16:     sbarrier();
Chris@16:   }
Chris@16: 
Chris@16: private:
Chris@16:   static int barrier()
Chris@16:   {
Chris@16:     int r = 0, m = 1;
Chris@16:     __asm__ __volatile__ (
Chris@16:         "xchgl %0, %1" :
Chris@16:         "=r"(r), "=m"(m) :
Chris@16:         "0"(1), "m"(m) :
Chris@16:         "memory", "cc");
Chris@16:     return r;
Chris@16:   }
Chris@16: 
Chris@16:   static void lbarrier()
Chris@16:   {
Chris@16: #if defined(__SSE2__)
Chris@101: # if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@101:     __builtin_ia32_lfence();
Chris@101: # else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@16:     __asm__ __volatile__ ("lfence" ::: "memory");
Chris@101: # endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@16: #else // defined(__SSE2__)
Chris@16:     barrier();
Chris@16: #endif // defined(__SSE2__)
Chris@16:   }
Chris@16: 
Chris@16:   static void sbarrier()
Chris@16:   {
Chris@16: #if defined(__SSE2__)
Chris@101: # if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@101:     __builtin_ia32_sfence();
Chris@101: # else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@16:     __asm__ __volatile__ ("sfence" ::: "memory");
Chris@101: # endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
Chris@16: #else // defined(__SSE2__)
Chris@16:     barrier();
Chris@16: #endif // defined(__SSE2__)
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: } // namespace detail
Chris@16: } // namespace asio
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #include <boost/asio/detail/pop_options.hpp>
Chris@16: 
Chris@16: #endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
Chris@16: 
Chris@16: #endif // BOOST_ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP