/*
 * Copyright (c) 2020, Microsoft Corporation. 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
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 */

#ifndef OS_CPU_WINDOWS_AARCH64_ATOMIC_WINDOWS_AARCH64_HPP
#define OS_CPU_WINDOWS_AARCH64_ATOMIC_WINDOWS_AARCH64_HPP

#include <intrin.h>
#include "runtime/os.hpp"
#include "runtime/vm_version.hpp"


// As per atomic.hpp all read-modify-write operations have to provide two-way
// barriers semantics. The memory_order parameter is ignored - we always provide
// the strongest/most-conservative ordering
//
// For AARCH64 we add explicit barriers in the stubs.

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

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

// The Interlocked* APIs only take long and will not accept __int32. That is
// acceptable on Windows, since long is a 32-bits integer type.

#define DEFINE_INTRINSIC_ADD(IntrinsicName, IntrinsicType)                \
  template<>                                                              \
  template<typename D, typename I>                                        \
  inline D Atomic::PlatformAdd<sizeof(IntrinsicType)>::add_then_fetch(D volatile* dest, \
                                                                      I add_value, \
                                                                      atomic_memory_order order) const { \
    STATIC_ASSERT(sizeof(IntrinsicType) == sizeof(D));                    \
    return PrimitiveConversions::cast<D>(                                 \
      IntrinsicName(reinterpret_cast<IntrinsicType volatile *>(dest),     \
                    PrimitiveConversions::cast<IntrinsicType>(add_value))); \
  }

DEFINE_INTRINSIC_ADD(InterlockedAdd,   long)
DEFINE_INTRINSIC_ADD(InterlockedAdd64, __int64)

#undef DEFINE_INTRINSIC_ADD

#define DEFINE_INTRINSIC_XCHG(IntrinsicName, IntrinsicType)               \
  template<>                                                              \
  template<typename T>                                                    \
  inline T Atomic::PlatformXchg<sizeof(IntrinsicType)>::operator()(T volatile* dest, \
                                                                   T exchange_value, \
                                                                   atomic_memory_order order) const { \
    STATIC_ASSERT(sizeof(IntrinsicType) == sizeof(T));                    \
    return PrimitiveConversions::cast<T>(                                 \
      IntrinsicName(reinterpret_cast<IntrinsicType volatile *>(dest),     \
                    PrimitiveConversions::cast<IntrinsicType>(exchange_value))); \
  }

DEFINE_INTRINSIC_XCHG(InterlockedExchange,   long)
DEFINE_INTRINSIC_XCHG(InterlockedExchange64, __int64)

#undef DEFINE_INTRINSIC_XCHG

// Note: the order of the parameters is different between
// Atomic::PlatformCmpxchg<*>::operator() and the
// InterlockedCompareExchange* API.

#define DEFINE_INTRINSIC_CMPXCHG(IntrinsicName, IntrinsicType)            \
  template<>                                                              \
  template<typename T>                                                    \
  inline T Atomic::PlatformCmpxchg<sizeof(IntrinsicType)>::operator()(T volatile* dest, \
                                                                      T compare_value, \
                                                                      T exchange_value, \
                                                                      atomic_memory_order order) const { \
    STATIC_ASSERT(sizeof(IntrinsicType) == sizeof(T));                    \
    return PrimitiveConversions::cast<T>(                                 \
      IntrinsicName(reinterpret_cast<IntrinsicType volatile *>(dest),     \
                    PrimitiveConversions::cast<IntrinsicType>(exchange_value), \
                    PrimitiveConversions::cast<IntrinsicType>(compare_value))); \
  }

DEFINE_INTRINSIC_CMPXCHG(_InterlockedCompareExchange8, char) // Use the intrinsic as InterlockedCompareExchange8 does not exist
DEFINE_INTRINSIC_CMPXCHG(InterlockedCompareExchange,   long)
DEFINE_INTRINSIC_CMPXCHG(InterlockedCompareExchange64, __int64)

#undef DEFINE_INTRINSIC_CMPXCHG

#endif // OS_CPU_WINDOWS_AARCH64_ATOMIC_WINDOWS_AARCH64_HPP