/*
 * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#ifndef OS_CPU_BSD_X86_ATOMICACCESS_BSD_X86_HPP
#define OS_CPU_BSD_X86_ATOMICACCESS_BSD_X86_HPP

// Implementation of class AtomicAccess

template<size_t byte_size>
struct AtomicAccess::PlatformAdd {
  template<typename D, typename I>
  D fetch_then_add(D volatile* dest, I add_value, atomic_memory_order /* order */) const;

  template<typename D, typename I>
  D add_then_fetch(D volatile* dest, I add_value, atomic_memory_order order) const {
    return fetch_then_add(dest, add_value, order) + add_value;
  }
};

template<>
template<typename D, typename I>
inline D AtomicAccess::PlatformAdd<4>::fetch_then_add(D volatile* dest, I add_value,
                                                      atomic_memory_order /* order */) const {
  STATIC_ASSERT(4 == sizeof(I));
  STATIC_ASSERT(4 == sizeof(D));
  D old_value;
  __asm__ volatile (  "lock xaddl %0,(%2)"
                    : "=r" (old_value)
                    : "0" (add_value), "r" (dest)
                    : "cc", "memory");
  return old_value;
}

template<>
struct AtomicAccess::PlatformXchg<1> : AtomicAccess::XchgUsingCmpxchg<1> {};

template<>
template<typename T>
inline T AtomicAccess::PlatformXchg<4>::operator()(T volatile* dest,
                                                   T exchange_value,
                                                   atomic_memory_order /* order */) const {
  STATIC_ASSERT(4 == sizeof(T));
  __asm__ volatile (  "xchgl (%2),%0"
                    : "=r" (exchange_value)
                    : "0" (exchange_value), "r" (dest)
                    : "memory");
  return exchange_value;
}

template<>
template<typename T>
inline T AtomicAccess::PlatformCmpxchg<1>::operator()(T volatile* dest,
                                                      T compare_value,
                                                      T exchange_value,
                                                      atomic_memory_order /* order */) const {
  STATIC_ASSERT(1 == sizeof(T));
  __asm__ volatile (  "lock cmpxchgb %1,(%3)"
                    : "=a" (exchange_value)
                    : "q" (exchange_value), "a" (compare_value), "r" (dest)
                    : "cc", "memory");
  return exchange_value;
}

template<>
template<typename T>
inline T AtomicAccess::PlatformCmpxchg<4>::operator()(T volatile* dest,
                                                      T compare_value,
                                                      T exchange_value,
                                                      atomic_memory_order /* order */) const {
  STATIC_ASSERT(4 == sizeof(T));
  __asm__ volatile (  "lock cmpxchgl %1,(%3)"
                    : "=a" (exchange_value)
                    : "r" (exchange_value), "a" (compare_value), "r" (dest)
                    : "cc", "memory");
  return exchange_value;
}

template<>
template<typename D, typename I>
inline D AtomicAccess::PlatformAdd<8>::fetch_then_add(D volatile* dest, I add_value,
                                                      atomic_memory_order /* order */) const {
  STATIC_ASSERT(8 == sizeof(I));
  STATIC_ASSERT(8 == sizeof(D));
  D old_value;
  __asm__ __volatile__ (  "lock xaddq %0,(%2)"
                        : "=r" (old_value)
                        : "0" (add_value), "r" (dest)
                        : "cc", "memory");
  return old_value;
}

template<>
template<typename T>
inline T AtomicAccess::PlatformXchg<8>::operator()(T volatile* dest,
                                                   T exchange_value,
                                                   atomic_memory_order /* order */) const {
  STATIC_ASSERT(8 == sizeof(T));
  __asm__ __volatile__ ("xchgq (%2),%0"
                        : "=r" (exchange_value)
                        : "0" (exchange_value), "r" (dest)
                        : "memory");
  return exchange_value;
}

template<>
template<typename T>
inline T AtomicAccess::PlatformCmpxchg<8>::operator()(T volatile* dest,
                                                      T compare_value,
                                                      T exchange_value,
                                                      atomic_memory_order /* order */) const {
  STATIC_ASSERT(8 == sizeof(T));
  __asm__ __volatile__ (  "lock cmpxchgq %1,(%3)"
                        : "=a" (exchange_value)
                        : "r" (exchange_value), "a" (compare_value), "r" (dest)
                        : "cc", "memory");
  return exchange_value;
}

template<>
struct AtomicAccess::PlatformOrderedStore<1, RELEASE_X_FENCE>
{
  template <typename T>
  void operator()(volatile T* p, T v) const {
    __asm__ volatile (  "xchgb (%2),%0"
                      : "=q" (v)
                      : "0" (v), "r" (p)
                      : "memory");
  }
};

template<>
struct AtomicAccess::PlatformOrderedStore<2, RELEASE_X_FENCE>
{
  template <typename T>
  void operator()(volatile T* p, T v) const {
    __asm__ volatile (  "xchgw (%2),%0"
                      : "=r" (v)
                      : "0" (v), "r" (p)
                      : "memory");
  }
};

template<>
struct AtomicAccess::PlatformOrderedStore<4, RELEASE_X_FENCE>
{
  template <typename T>
  void operator()(volatile T* p, T v) const {
    __asm__ volatile (  "xchgl (%2),%0"
                      : "=r" (v)
                      : "0" (v), "r" (p)
                      : "memory");
  }
};

template<>
struct AtomicAccess::PlatformOrderedStore<8, RELEASE_X_FENCE>
{
  template <typename T>
  void operator()(volatile T* p, T v) const {
    __asm__ volatile (  "xchgq (%2), %0"
                      : "=r" (v)
                      : "0" (v), "r" (p)
                      : "memory");
  }
};

#endif // OS_CPU_BSD_X86_ATOMICACCESS_BSD_X86_HPP