/*
 * Copyright (c) 2003, 2016, 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
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#ifndef OS_CPU_WINDOWS_X86_VM_ORDERACCESS_WINDOWS_X86_INLINE_HPP
#define OS_CPU_WINDOWS_X86_VM_ORDERACCESS_WINDOWS_X86_INLINE_HPP

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

// Compiler version last used for testing: Microsoft Visual Studio 2010
// Please update this information when this file changes

// Implementation of class OrderAccess.

// A compiler barrier, forcing the C++ compiler to invalidate all memory assumptions
inline void compiler_barrier() {
  _ReadWriteBarrier();
}

// Note that in MSVC, volatile memory accesses are explicitly
// guaranteed to have acquire release semantics (w.r.t. compiler
// reordering) and therefore does not even need a compiler barrier
// for normal acquire release accesses. And all generalized
// bound calls like release_store go through OrderAccess::load
// and OrderAccess::store which do volatile memory accesses.
template<> inline void ScopedFence<X_ACQUIRE>::postfix()       { }
template<> inline void ScopedFence<RELEASE_X>::prefix()        { }
template<> inline void ScopedFence<RELEASE_X_FENCE>::prefix()  { }
template<> inline void ScopedFence<RELEASE_X_FENCE>::postfix() { OrderAccess::fence(); }

inline void OrderAccess::loadload()   { compiler_barrier(); }
inline void OrderAccess::storestore() { compiler_barrier(); }
inline void OrderAccess::loadstore()  { compiler_barrier(); }
inline void OrderAccess::storeload()  { fence(); }

inline void OrderAccess::acquire()    { compiler_barrier(); }
inline void OrderAccess::release()    { compiler_barrier(); }

inline void OrderAccess::fence() {
#ifdef AMD64
  StubRoutines_fence();
#else
  if (os::is_MP()) {
    __asm {
      lock add dword ptr [esp], 0;
    }
  }
#endif // AMD64
  compiler_barrier();
}

#ifndef AMD64
template<>
inline void OrderAccess::specialized_release_store_fence<jbyte> (volatile jbyte*  p, jbyte  v) {
  __asm {
    mov edx, p;
    mov al, v;
    xchg al, byte ptr [edx];
  }
}

template<>
inline void OrderAccess::specialized_release_store_fence<jshort>(volatile jshort* p, jshort v) {
  __asm {
    mov edx, p;
    mov ax, v;
    xchg ax, word ptr [edx];
  }
}

template<>
inline void OrderAccess::specialized_release_store_fence<jint>  (volatile jint*   p, jint   v) {
  __asm {
    mov edx, p;
    mov eax, v;
    xchg eax, dword ptr [edx];
  }
}
#endif // AMD64

template<>
inline void OrderAccess::specialized_release_store_fence<jfloat>(volatile jfloat*  p, jfloat  v) {
    release_store_fence((volatile jint*)p, jint_cast(v));
}
template<>
inline void OrderAccess::specialized_release_store_fence<jdouble>(volatile jdouble* p, jdouble v) {
    release_store_fence((volatile jlong*)p, jlong_cast(v));
}

#define VM_HAS_GENERALIZED_ORDER_ACCESS 1

#endif // OS_CPU_WINDOWS_X86_VM_ORDERACCESS_WINDOWS_X86_INLINE_HPP