| // |
| // detail/gcc_x86_fenced_block.hpp |
| // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| |
| #ifndef ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP |
| #define ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| |
| #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
| |
| #include "asio/detail/noncopyable.hpp" |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| namespace detail { |
| |
| class gcc_x86_fenced_block |
| : private noncopyable |
| { |
| public: |
| enum half_t { half }; |
| enum full_t { full }; |
| |
| // Constructor for a half fenced block. |
| explicit gcc_x86_fenced_block(half_t) |
| { |
| } |
| |
| // Constructor for a full fenced block. |
| explicit gcc_x86_fenced_block(full_t) |
| { |
| lbarrier(); |
| } |
| |
| // Destructor. |
| ~gcc_x86_fenced_block() |
| { |
| sbarrier(); |
| } |
| |
| private: |
| static int barrier() |
| { |
| int r = 0, m = 1; |
| __asm__ __volatile__ ( |
| "xchgl %0, %1" : |
| "=r"(r), "=m"(m) : |
| "0"(1), "m"(m) : |
| "memory", "cc"); |
| return r; |
| } |
| |
| static void lbarrier() |
| { |
| #if defined(__SSE2__) |
| # if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| __builtin_ia32_lfence(); |
| # else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| __asm__ __volatile__ ("lfence" ::: "memory"); |
| # endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| #else // defined(__SSE2__) |
| barrier(); |
| #endif // defined(__SSE2__) |
| } |
| |
| static void sbarrier() |
| { |
| #if defined(__SSE2__) |
| # if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| __builtin_ia32_sfence(); |
| # else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| __asm__ __volatile__ ("sfence" ::: "memory"); |
| # endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL) |
| #else // defined(__SSE2__) |
| barrier(); |
| #endif // defined(__SSE2__) |
| } |
| }; |
| |
| } // namespace detail |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
| |
| #endif // ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP |