/* * 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) * * Copyright (c) 2017 Andrey Semashev */ /*! * \file atomic/detail/hwcaps_gcc_arm.hpp * * This header defines hardware capabilities macros for ARM */ #ifndef BOOST_ATOMIC_DETAIL_HWCAPS_GCC_ARM_HPP_INCLUDED_ #define BOOST_ATOMIC_DETAIL_HWCAPS_GCC_ARM_HPP_INCLUDED_ #include #include #ifdef BOOST_HAS_PRAGMA_ONCE #pragma once #endif #if defined(__GNUC__) && defined(__arm__) && (BOOST_ATOMIC_DETAIL_ARM_ARCH+0) >= 6 #if BOOST_ATOMIC_DETAIL_ARM_ARCH > 6 // ARMv7 and later have dmb instruction #define BOOST_ATOMIC_DETAIL_ARM_HAS_DMB 1 #endif #if defined(__ARM_FEATURE_LDREX) #if (__ARM_FEATURE_LDREX & 1) #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXB_STREXB 1 #endif #if (__ARM_FEATURE_LDREX & 2) #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXH_STREXH 1 #endif #if (__ARM_FEATURE_LDREX & 8) #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXD_STREXD 1 #endif #else // defined(__ARM_FEATURE_LDREX) #if !(defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6Z__)) // ARMv6k and ARMv7 have 8 and 16-bit ldrex/strex variants, but at least GCC 4.7 fails to compile them. GCC 4.9 is known to work. #if (__GNUC__ * 100 + __GNUC_MINOR__) >= 409 #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXB_STREXB 1 #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXH_STREXH 1 #endif #if !(((defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6ZK__)) && defined(__thumb__)) || defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7M__)) // ARMv6k and ARMv7 except ARMv7-M have 64-bit ldrex/strex variants. // Unfortunately, GCC (at least 4.7.3 on Ubuntu) does not allocate register pairs properly when targeting ARMv6k Thumb, // which is required for ldrexd/strexd instructions, so we disable 64-bit support. When targeting ARMv6k ARM // or ARMv7 (both ARM and Thumb 2) it works as expected. #define BOOST_ATOMIC_DETAIL_ARM_HAS_LDREXD_STREXD 1 #endif #endif // !(defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6Z__)) #endif // defined(__ARM_FEATURE_LDREX) #endif // defined(__GNUC__) && defined(__arm__) && (BOOST_ATOMIC_DETAIL_ARM_ARCH+0) >= 6 #endif // BOOST_ATOMIC_DETAIL_HWCAPS_GCC_ARM_HPP_INCLUDED_