/* * 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) 2009 Helge Bahmann * Copyright (c) 2012 Tim Blechmann * Copyright (c) 2014 Andrey Semashev */ /*! * \file atomic/detail/core_arch_ops_gcc_x86.hpp * * This header contains implementation of the \c core_arch_operations template. */ #ifndef BOOST_ATOMIC_DETAIL_CORE_ARCH_OPS_GCC_X86_HPP_INCLUDED_ #define BOOST_ATOMIC_DETAIL_CORE_ARCH_OPS_GCC_X86_HPP_INCLUDED_ #include #include #include #include #include #include #if defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG8B) || defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG16B) #include #include #include #include #endif #include #ifdef BOOST_HAS_PRAGMA_ONCE #pragma once #endif namespace boost { namespace atomics { namespace detail { struct core_arch_operations_gcc_x86_base { static BOOST_CONSTEXPR_OR_CONST bool full_cas_based = false; static BOOST_CONSTEXPR_OR_CONST bool is_always_lock_free = true; static BOOST_FORCEINLINE void fence_before(memory_order order) BOOST_NOEXCEPT { if ((static_cast< unsigned int >(order) & static_cast< unsigned int >(memory_order_release)) != 0u) __asm__ __volatile__ ("" ::: "memory"); } static BOOST_FORCEINLINE void fence_after(memory_order order) BOOST_NOEXCEPT { if ((static_cast< unsigned int >(order) & (static_cast< unsigned int >(memory_order_consume) | static_cast< unsigned int >(memory_order_acquire))) != 0u) __asm__ __volatile__ ("" ::: "memory"); } }; template< std::size_t Size, bool Signed, bool Interprocess, typename Derived > struct core_arch_operations_gcc_x86 : public core_arch_operations_gcc_x86_base { typedef typename storage_traits< Size >::type storage_type; static BOOST_CONSTEXPR_OR_CONST std::size_t storage_size = Size; static BOOST_CONSTEXPR_OR_CONST std::size_t storage_alignment = Size; static BOOST_CONSTEXPR_OR_CONST bool is_signed = Signed; static BOOST_CONSTEXPR_OR_CONST bool is_interprocess = Interprocess; static BOOST_FORCEINLINE void store(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT { if (order != memory_order_seq_cst) { fence_before(order); storage = v; fence_after(order); } else { Derived::exchange(storage, v, order); } } static BOOST_FORCEINLINE storage_type load(storage_type const volatile& storage, memory_order order) BOOST_NOEXCEPT { storage_type v = storage; fence_after(order); return v; } static BOOST_FORCEINLINE storage_type fetch_sub(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT { return Derived::fetch_add(storage, -v, order); } static BOOST_FORCEINLINE bool compare_exchange_weak( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { return Derived::compare_exchange_strong(storage, expected, desired, success_order, failure_order); } static BOOST_FORCEINLINE bool test_and_set(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT { return !!Derived::exchange(storage, (storage_type)1, order); } static BOOST_FORCEINLINE void clear(storage_type volatile& storage, memory_order order) BOOST_NOEXCEPT { store(storage, (storage_type)0, order); } }; template< bool Signed, bool Interprocess > struct core_arch_operations< 1u, Signed, Interprocess > : public core_arch_operations_gcc_x86< 1u, Signed, Interprocess, core_arch_operations< 1u, Signed, Interprocess > > { typedef core_arch_operations_gcc_x86< 1u, Signed, Interprocess, core_arch_operations< 1u, Signed, Interprocess > > base_type; typedef typename base_type::storage_type storage_type; typedef typename storage_traits< 4u >::type temp_storage_type; static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "lock; xaddb %0, %1" : "+q" (v), "+m" (storage) : : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return v; } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "xchgb %0, %1" : "+q" (v), "+m" (storage) : : "memory" ); return v; } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { storage_type previous = expected; bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgb %3, %1" : "+a" (previous), "+m" (storage), "=@ccz" (success) : "q" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgb %3, %1\n\t" "sete %2" : "+a" (previous), "+m" (storage), "=q" (success) : "q" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) expected = previous; return success; } #define BOOST_ATOMIC_DETAIL_CAS_LOOP(op, argument, result)\ temp_storage_type new_val;\ __asm__ __volatile__\ (\ ".align 16\n\t"\ "1: mov %[arg], %2\n\t"\ op " %%al, %b2\n\t"\ "lock; cmpxchgb %b2, %[storage]\n\t"\ "jne 1b"\ : [res] "+a" (result), [storage] "+m" (storage), "=&q" (new_val)\ : [arg] "ir" ((temp_storage_type)argument)\ : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory"\ ) static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("andb", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("orb", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("xorb", v, res); return res; } #undef BOOST_ATOMIC_DETAIL_CAS_LOOP }; template< bool Signed, bool Interprocess > struct core_arch_operations< 2u, Signed, Interprocess > : public core_arch_operations_gcc_x86< 2u, Signed, Interprocess, core_arch_operations< 2u, Signed, Interprocess > > { typedef core_arch_operations_gcc_x86< 2u, Signed, Interprocess, core_arch_operations< 2u, Signed, Interprocess > > base_type; typedef typename base_type::storage_type storage_type; typedef typename storage_traits< 4u >::type temp_storage_type; static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "lock; xaddw %0, %1" : "+q" (v), "+m" (storage) : : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return v; } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "xchgw %0, %1" : "+q" (v), "+m" (storage) : : "memory" ); return v; } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { storage_type previous = expected; bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgw %3, %1" : "+a" (previous), "+m" (storage), "=@ccz" (success) : "q" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgw %3, %1\n\t" "sete %2" : "+a" (previous), "+m" (storage), "=q" (success) : "q" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) expected = previous; return success; } #define BOOST_ATOMIC_DETAIL_CAS_LOOP(op, argument, result)\ temp_storage_type new_val;\ __asm__ __volatile__\ (\ ".align 16\n\t"\ "1: mov %[arg], %2\n\t"\ op " %%ax, %w2\n\t"\ "lock; cmpxchgw %w2, %[storage]\n\t"\ "jne 1b"\ : [res] "+a" (result), [storage] "+m" (storage), "=&q" (new_val)\ : [arg] "ir" ((temp_storage_type)argument)\ : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory"\ ) static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("andw", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("orw", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("xorw", v, res); return res; } #undef BOOST_ATOMIC_DETAIL_CAS_LOOP }; template< bool Signed, bool Interprocess > struct core_arch_operations< 4u, Signed, Interprocess > : public core_arch_operations_gcc_x86< 4u, Signed, Interprocess, core_arch_operations< 4u, Signed, Interprocess > > { typedef core_arch_operations_gcc_x86< 4u, Signed, Interprocess, core_arch_operations< 4u, Signed, Interprocess > > base_type; typedef typename base_type::storage_type storage_type; static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "lock; xaddl %0, %1" : "+r" (v), "+m" (storage) : : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return v; } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "xchgl %0, %1" : "+r" (v), "+m" (storage) : : "memory" ); return v; } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { storage_type previous = expected; bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgl %3, %1" : "+a" (previous), "+m" (storage), "=@ccz" (success) : "r" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgl %3, %1\n\t" "sete %2" : "+a" (previous), "+m" (storage), "=q" (success) : "r" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) expected = previous; return success; } #define BOOST_ATOMIC_DETAIL_CAS_LOOP(op, argument, result)\ storage_type new_val;\ __asm__ __volatile__\ (\ ".align 16\n\t"\ "1: mov %[arg], %[new_val]\n\t"\ op " %%eax, %[new_val]\n\t"\ "lock; cmpxchgl %[new_val], %[storage]\n\t"\ "jne 1b"\ : [res] "+a" (result), [storage] "+m" (storage), [new_val] "=&r" (new_val)\ : [arg] "ir" (argument)\ : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory"\ ) static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("andl", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("orl", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("xorl", v, res); return res; } #undef BOOST_ATOMIC_DETAIL_CAS_LOOP }; #if defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG8B) // Note: In the 32-bit PIC code guarded with BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX below we have to avoid using memory // operand constraints because the compiler may choose to use ebx as the base register for that operand. At least, clang // is known to do that. For this reason we have to pre-compute a pointer to storage and pass it in edi. For the same reason // we cannot save ebx to the stack with a mov instruction, so we use esi as a scratch register and restore it afterwards. // Alternatively, we could push/pop the register to the stack, but exchanging the registers is faster. // The need to pass a pointer in edi is a bit wasteful because normally the memory operand would use a base pointer // with an offset (e.g. `this` + offset). But unfortunately, there seems to be no way around it. template< bool Signed, bool Interprocess > struct gcc_dcas_x86 { typedef typename storage_traits< 8u >::type storage_type; typedef uint32_t BOOST_ATOMIC_DETAIL_MAY_ALIAS aliasing_uint32_t; #if defined(__SSE2__) typedef uint32_t xmm_t __attribute__((__vector_size__(16))); #elif defined(__SSE__) typedef float xmm_t __attribute__((__vector_size__(16))); #endif static BOOST_CONSTEXPR_OR_CONST std::size_t storage_size = 8u; static BOOST_CONSTEXPR_OR_CONST std::size_t storage_alignment = 8u; static BOOST_CONSTEXPR_OR_CONST bool is_signed = Signed; static BOOST_CONSTEXPR_OR_CONST bool is_interprocess = Interprocess; static BOOST_CONSTEXPR_OR_CONST bool full_cas_based = true; static BOOST_CONSTEXPR_OR_CONST bool is_always_lock_free = true; static BOOST_FORCEINLINE void store(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT { if (BOOST_LIKELY(order != memory_order_seq_cst && (((uintptr_t)&storage) & 7u) == 0u)) { #if defined(__SSE__) #if defined(__SSE2__) xmm_t value = { static_cast< uint32_t >(v), static_cast< uint32_t >(v >> 32u), 0u, 0u }; #else xmm_t value; BOOST_ATOMIC_DETAIL_MEMSET(&value, 0, sizeof(value)); BOOST_ATOMIC_DETAIL_MEMCPY(&value, &v, sizeof(v)); #endif __asm__ __volatile__ ( #if defined(__AVX__) "vmovq %[value], %[storage]\n\t" #elif defined(__SSE2__) "movq %[value], %[storage]\n\t" #else "movlps %[value], %[storage]\n\t" #endif : [storage] "=m" (storage) : [value] "x" (value) : "memory" ); #else // defined(__SSE__) __asm__ __volatile__ ( "fildll %[value]\n\t" "fistpll %[storage]\n\t" : [storage] "=m" (storage) : [value] "m" (v) : "memory" ); #endif // defined(__SSE__) } else { #if defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) __asm__ __volatile__ ( "xchgl %%ebx, %%esi\n\t" "movl %%eax, %%ebx\n\t" "movl (%[dest]), %%eax\n\t" "movl 4(%[dest]), %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b (%[dest])\n\t" "jne 1b\n\t" "xchgl %%ebx, %%esi\n\t" : : "a" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)), [dest] "D" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "edx", "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) __asm__ __volatile__ ( "movl %[dest_lo], %%eax\n\t" "movl %[dest_hi], %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b %[dest_lo]\n\t" "jne 1b\n\t" : [dest_lo] "=m" (storage), [dest_hi] "=m" (reinterpret_cast< volatile aliasing_uint32_t* >(&storage)[1]) : [value_lo] "b" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "eax", "edx", "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) } } static BOOST_FORCEINLINE storage_type load(storage_type const volatile& storage, memory_order) BOOST_NOEXCEPT { storage_type value; if (BOOST_LIKELY((((uintptr_t)&storage) & 7u) == 0u)) { #if defined(__SSE__) xmm_t v; __asm__ __volatile__ ( #if defined(__AVX__) "vmovq %[storage], %[value]\n\t" #elif defined(__SSE2__) "movq %[storage], %[value]\n\t" #else "xorps %[value], %[value]\n\t" "movlps %[storage], %[value]\n\t" #endif : [value] "=x" (v) : [storage] "m" (storage) : "memory" ); #if defined(__SSE2__) && (!defined(BOOST_GCC) || BOOST_GCC >= 40800) // gcc prior to 4.8 don't support subscript operator for vector types value = static_cast< storage_type >(v[0]) | (static_cast< storage_type >(v[1]) << 32u); #else BOOST_ATOMIC_DETAIL_MEMCPY(&value, &v, sizeof(value)); #endif #else // defined(__SSE__) __asm__ __volatile__ ( "fildll %[storage]\n\t" "fistpll %[value]\n\t" : [value] "=m" (value) : [storage] "m" (storage) : "memory" ); #endif // defined(__SSE__) } else { // Note that despite const qualification cmpxchg8b below may issue a store to the storage. The storage value // will not change, but this prevents the storage to reside in read-only memory. #if defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) uint32_t value_bits[2]; // We don't care for comparison result here; the previous value will be stored into value anyway. // Also we don't care for ebx and ecx values, they just have to be equal to eax and edx before cmpxchg8b. __asm__ __volatile__ ( "movl %%ebx, %%eax\n\t" "movl %%ecx, %%edx\n\t" "lock; cmpxchg8b %[storage]\n\t" : "=&a" (value_bits[0]), "=&d" (value_bits[1]) : [storage] "m" (storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); value = static_cast< storage_type >(value_bits[0]) | (static_cast< storage_type >(value_bits[1]) << 32u); #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) // We don't care for comparison result here; the previous value will be stored into value anyway. // Also we don't care for ebx and ecx values, they just have to be equal to eax and edx before cmpxchg8b. __asm__ __volatile__ ( "movl %%ebx, %%eax\n\t" "movl %%ecx, %%edx\n\t" "lock; cmpxchg8b %[storage]\n\t" : "=&A" (value) : [storage] "m" (storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) } return value; } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { #if defined(__clang__) // Clang cannot allocate eax:edx register pairs but it has sync intrinsics storage_type old_expected = expected; expected = __sync_val_compare_and_swap(&storage, old_expected, desired); return expected == old_expected; #elif defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "xchgl %%ebx, %%esi\n\t" "lock; cmpxchg8b (%[dest])\n\t" "xchgl %%ebx, %%esi\n\t" : "+A" (expected), [success] "=@ccz" (success) : "S" ((uint32_t)desired), "c" ((uint32_t)(desired >> 32u)), [dest] "D" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "xchgl %%ebx, %%esi\n\t" "lock; cmpxchg8b (%[dest])\n\t" "xchgl %%ebx, %%esi\n\t" "sete %[success]\n\t" : "+A" (expected), [success] "=qm" (success) : "S" ((uint32_t)desired), "c" ((uint32_t)(desired >> 32u)), [dest] "D" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) return success; #else // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchg8b %[dest]\n\t" : "+A" (expected), [dest] "+m" (storage), [success] "=@ccz" (success) : "b" ((uint32_t)desired), "c" ((uint32_t)(desired >> 32u)) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchg8b %[dest]\n\t" "sete %[success]\n\t" : "+A" (expected), [dest] "+m" (storage), [success] "=qm" (success) : "b" ((uint32_t)desired), "c" ((uint32_t)(desired >> 32u)) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) return success; #endif // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) } static BOOST_FORCEINLINE bool compare_exchange_weak( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { return compare_exchange_strong(storage, expected, desired, success_order, failure_order); } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) #if defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) uint32_t old_bits[2]; __asm__ __volatile__ ( "xchgl %%ebx, %%esi\n\t" "movl (%[dest]), %%eax\n\t" "movl 4(%[dest]), %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b (%[dest])\n\t" "jne 1b\n\t" "xchgl %%ebx, %%esi\n\t" : "=a" (old_bits[0]), "=d" (old_bits[1]) : "S" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)), [dest] "D" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); storage_type old_value; BOOST_ATOMIC_DETAIL_MEMCPY(&old_value, old_bits, sizeof(old_value)); return old_value; #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) storage_type old_value; __asm__ __volatile__ ( "xchgl %%ebx, %%esi\n\t" "movl (%[dest]), %%eax\n\t" "movl 4(%[dest]), %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b (%[dest])\n\t" "jne 1b\n\t" "xchgl %%ebx, %%esi\n\t" : "=A" (old_value) : "S" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)), [dest] "D" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return old_value; #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) #else // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) #if defined(__MINGW32__) && ((__GNUC__+0) * 100 + (__GNUC_MINOR__+0)) < 407 // MinGW gcc up to 4.6 has problems with allocating registers in the asm blocks below uint32_t old_bits[2]; __asm__ __volatile__ ( "movl (%[dest]), %%eax\n\t" "movl 4(%[dest]), %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b (%[dest])\n\t" "jne 1b\n\t" : "=&a" (old_bits[0]), "=&d" (old_bits[1]) : "b" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)), [dest] "DS" (&storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); storage_type old_value; BOOST_ATOMIC_DETAIL_MEMCPY(&old_value, old_bits, sizeof(old_value)); return old_value; #elif defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) uint32_t old_bits[2]; __asm__ __volatile__ ( "movl %[dest_lo], %%eax\n\t" "movl %[dest_hi], %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b %[dest_lo]\n\t" "jne 1b\n\t" : "=&a" (old_bits[0]), "=&d" (old_bits[1]), [dest_lo] "+m" (storage), [dest_hi] "+m" (reinterpret_cast< volatile aliasing_uint32_t* >(&storage)[1]) : "b" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); storage_type old_value; BOOST_ATOMIC_DETAIL_MEMCPY(&old_value, old_bits, sizeof(old_value)); return old_value; #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) storage_type old_value; __asm__ __volatile__ ( "movl %[dest_lo], %%eax\n\t" "movl %[dest_hi], %%edx\n\t" ".align 16\n\t" "1: lock; cmpxchg8b %[dest_lo]\n\t" "jne 1b\n\t" : "=&A" (old_value), [dest_lo] "+m" (storage), [dest_hi] "+m" (reinterpret_cast< volatile aliasing_uint32_t* >(&storage)[1]) : "b" ((uint32_t)v), "c" ((uint32_t)(v >> 32u)) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return old_value; #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) #endif // defined(BOOST_ATOMIC_DETAIL_X86_ASM_PRESERVE_EBX) } }; template< bool Signed, bool Interprocess > struct core_arch_operations< 8u, Signed, Interprocess > : public core_operations_cas_based< gcc_dcas_x86< Signed, Interprocess > > { }; #elif defined(__x86_64__) template< bool Signed, bool Interprocess > struct core_arch_operations< 8u, Signed, Interprocess > : public core_arch_operations_gcc_x86< 8u, Signed, Interprocess, core_arch_operations< 8u, Signed, Interprocess > > { typedef core_arch_operations_gcc_x86< 8u, Signed, Interprocess, core_arch_operations< 8u, Signed, Interprocess > > base_type; typedef typename base_type::storage_type storage_type; static BOOST_FORCEINLINE storage_type fetch_add(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "lock; xaddq %0, %1" : "+r" (v), "+m" (storage) : : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return v; } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { __asm__ __volatile__ ( "xchgq %0, %1" : "+r" (v), "+m" (storage) : : "memory" ); return v; } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { storage_type previous = expected; bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgq %3, %1" : "+a" (previous), "+m" (storage), "=@ccz" (success) : "r" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchgq %3, %1\n\t" "sete %2" : "+a" (previous), "+m" (storage), "=q" (success) : "r" (desired) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) expected = previous; return success; } #define BOOST_ATOMIC_DETAIL_CAS_LOOP(op, argument, result)\ storage_type new_val;\ __asm__ __volatile__\ (\ ".align 16\n\t"\ "1: movq %[arg], %[new_val]\n\t"\ op " %%rax, %[new_val]\n\t"\ "lock; cmpxchgq %[new_val], %[storage]\n\t"\ "jne 1b"\ : [res] "+a" (result), [storage] "+m" (storage), [new_val] "=&r" (new_val)\ : [arg] "r" (argument)\ : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory"\ ) static BOOST_FORCEINLINE storage_type fetch_and(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("andq", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_or(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("orq", v, res); return res; } static BOOST_FORCEINLINE storage_type fetch_xor(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { storage_type res = storage; BOOST_ATOMIC_DETAIL_CAS_LOOP("xorq", v, res); return res; } #undef BOOST_ATOMIC_DETAIL_CAS_LOOP }; #endif #if defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG16B) template< bool Signed, bool Interprocess > struct gcc_dcas_x86_64 { typedef typename storage_traits< 16u >::type storage_type; typedef uint64_t BOOST_ATOMIC_DETAIL_MAY_ALIAS aliasing_uint64_t; #if defined(__AVX__) typedef uint64_t __attribute__((__vector_size__(16))) xmm_t; #endif static BOOST_CONSTEXPR_OR_CONST std::size_t storage_size = 16u; static BOOST_CONSTEXPR_OR_CONST std::size_t storage_alignment = 16u; static BOOST_CONSTEXPR_OR_CONST bool is_signed = Signed; static BOOST_CONSTEXPR_OR_CONST bool is_interprocess = Interprocess; static BOOST_CONSTEXPR_OR_CONST bool full_cas_based = true; static BOOST_CONSTEXPR_OR_CONST bool is_always_lock_free = true; static BOOST_FORCEINLINE void store(storage_type volatile& storage, storage_type v, memory_order order) BOOST_NOEXCEPT { #if defined(__AVX__) if (BOOST_LIKELY(order != memory_order_seq_cst && (((uintptr_t)&storage) & 15u) == 0u)) { // According to SDM Volume 3, 8.1.1 Guaranteed Atomic Operations, processors supporting AVX guarantee // aligned vector moves to be atomic. #if defined(BOOST_HAS_INT128) xmm_t value = { static_cast< uint64_t >(v), static_cast< uint64_t >(v >> 64u) }; #else xmm_t value; BOOST_ATOMIC_DETAIL_MEMCPY(&value, &v, sizeof(v)); #endif __asm__ __volatile__ ( "vmovdqa %[value], %[storage]\n\t" : [storage] "=m" (storage) : [value] "x" (value) : "memory" ); return; } #endif // defined(__AVX__) __asm__ __volatile__ ( "movq %[dest_lo], %%rax\n\t" "movq %[dest_hi], %%rdx\n\t" ".align 16\n\t" "1: lock; cmpxchg16b %[dest_lo]\n\t" "jne 1b\n\t" : [dest_lo] "=m" (storage), [dest_hi] "=m" (reinterpret_cast< volatile aliasing_uint64_t* >(&storage)[1]) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&v)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&v)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "rax", "rdx", "memory" ); } static BOOST_FORCEINLINE storage_type load(storage_type const volatile& storage, memory_order) BOOST_NOEXCEPT { #if defined(__AVX__) if (BOOST_LIKELY((((uintptr_t)&storage) & 15u) == 0u)) { // According to SDM Volume 3, 8.1.1 Guaranteed Atomic Operations, processors supporting AVX guarantee // aligned vector moves to be atomic. xmm_t v; __asm__ __volatile__ ( "vmovdqa %[storage], %[value]\n\t" : [value] "=x" (v) : [storage] "m" (storage) : "memory" ); #if defined(BOOST_HAS_INT128) && (!defined(BOOST_GCC) || BOOST_GCC >= 40800) // gcc prior to 4.8 don't support subscript operator for vector types storage_type value = static_cast< storage_type >(v[0]) | (static_cast< storage_type >(v[1]) << 64u); #else storage_type value; BOOST_ATOMIC_DETAIL_MEMCPY(&value, &v, sizeof(v)); #endif return value; } #endif // defined(__AVX__) // Note that despite const qualification cmpxchg16b below may issue a store to the storage. The storage value // will not change, but this prevents the storage to reside in read-only memory. #if defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) uint64_t value_bits[2]; // We don't care for comparison result here; the previous value will be stored into value anyway. // Also we don't care for rbx and rcx values, they just have to be equal to rax and rdx before cmpxchg16b. __asm__ __volatile__ ( "movq %%rbx, %%rax\n\t" "movq %%rcx, %%rdx\n\t" "lock; cmpxchg16b %[storage]\n\t" : "=&a" (value_bits[0]), "=&d" (value_bits[1]) : [storage] "m" (storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #if defined(BOOST_HAS_INT128) storage_type value = static_cast< storage_type >(value_bits[0]) | (static_cast< storage_type >(value_bits[1]) << 64u); #else storage_type value; BOOST_ATOMIC_DETAIL_MEMCPY(&value, value_bits, sizeof(value)); #endif return value; #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) storage_type value; // We don't care for comparison result here; the previous value will be stored into value anyway. // Also we don't care for rbx and rcx values, they just have to be equal to rax and rdx before cmpxchg16b. __asm__ __volatile__ ( "movq %%rbx, %%rax\n\t" "movq %%rcx, %%rdx\n\t" "lock; cmpxchg16b %[storage]\n\t" : "=&A" (value) : [storage] "m" (storage) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return value; #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) } static BOOST_FORCEINLINE bool compare_exchange_strong( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order, memory_order) BOOST_NOEXCEPT { #if defined(__clang__) // Clang cannot allocate rax:rdx register pairs but it has sync intrinsics storage_type old_expected = expected; expected = __sync_val_compare_and_swap(&storage, old_expected, desired); return expected == old_expected; #elif defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) // Some compilers can't allocate rax:rdx register pair either but also don't support 128-bit __sync_val_compare_and_swap bool success; __asm__ __volatile__ ( "lock; cmpxchg16b %[dest]\n\t" "sete %[success]\n\t" : [dest] "+m" (storage), "+a" (reinterpret_cast< aliasing_uint64_t* >(&expected)[0]), "+d" (reinterpret_cast< aliasing_uint64_t* >(&expected)[1]), [success] "=q" (success) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return success; #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) bool success; #if defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchg16b %[dest]\n\t" : "+A" (expected), [dest] "+m" (storage), "=@ccz" (success) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #else // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) __asm__ __volatile__ ( "lock; cmpxchg16b %[dest]\n\t" "sete %[success]\n\t" : "+A" (expected), [dest] "+m" (storage), [success] "=qm" (success) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&desired)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #endif // defined(BOOST_ATOMIC_DETAIL_ASM_HAS_FLAG_OUTPUTS) return success; #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) } static BOOST_FORCEINLINE bool compare_exchange_weak( storage_type volatile& storage, storage_type& expected, storage_type desired, memory_order success_order, memory_order failure_order) BOOST_NOEXCEPT { return compare_exchange_strong(storage, expected, desired, success_order, failure_order); } static BOOST_FORCEINLINE storage_type exchange(storage_type volatile& storage, storage_type v, memory_order) BOOST_NOEXCEPT { #if defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) uint64_t old_bits[2]; __asm__ __volatile__ ( "movq %[dest_lo], %%rax\n\t" "movq %[dest_hi], %%rdx\n\t" ".align 16\n\t" "1: lock; cmpxchg16b %[dest_lo]\n\t" "jne 1b\n\t" : [dest_lo] "+m" (storage), [dest_hi] "+m" (reinterpret_cast< volatile aliasing_uint64_t* >(&storage)[1]), "=&a" (old_bits[0]), "=&d" (old_bits[1]) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&v)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&v)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); #if defined(BOOST_HAS_INT128) storage_type old_value = static_cast< storage_type >(old_bits[0]) | (static_cast< storage_type >(old_bits[1]) << 64u); #else storage_type old_value; BOOST_ATOMIC_DETAIL_MEMCPY(&old_value, old_bits, sizeof(old_value)); #endif return old_value; #else // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) storage_type old_value; __asm__ __volatile__ ( "movq %[dest_lo], %%rax\n\t" "movq %[dest_hi], %%rdx\n\t" ".align 16\n\t" "1: lock; cmpxchg16b %[dest_lo]\n\t" "jne 1b\n\t" : "=&A" (old_value), [dest_lo] "+m" (storage), [dest_hi] "+m" (reinterpret_cast< volatile aliasing_uint64_t* >(&storage)[1]) : "b" (reinterpret_cast< const aliasing_uint64_t* >(&v)[0]), "c" (reinterpret_cast< const aliasing_uint64_t* >(&v)[1]) : BOOST_ATOMIC_DETAIL_ASM_CLOBBER_CC_COMMA "memory" ); return old_value; #endif // defined(BOOST_ATOMIC_DETAIL_X86_NO_ASM_AX_DX_PAIRS) } }; template< bool Signed, bool Interprocess > struct core_arch_operations< 16u, Signed, Interprocess > : public core_operations_cas_based< gcc_dcas_x86_64< Signed, Interprocess > > { }; #endif // defined(BOOST_ATOMIC_DETAIL_X86_HAS_CMPXCHG16B) } // namespace detail } // namespace atomics } // namespace boost #include #endif // BOOST_ATOMIC_DETAIL_CORE_ARCH_OPS_GCC_X86_HPP_INCLUDED_