#ifndef ATOMIC_MSC_INCLUDED
#define ATOMIC_MSC_INCLUDED

/* Copyright (c) 2006, 2021, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program 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 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#include <windows.h>

static inline int my_atomic_cas32(int32 volatile *a, int32 *cmp, int32 set)
{
  int32 initial_cmp= *cmp;
  int32 initial_a= InterlockedCompareExchange((volatile LONG*)a,
                                              set, initial_cmp);
  int ret= (initial_a == initial_cmp);
  if (!ret)
    *cmp= initial_a;
  return ret;
}

static inline int my_atomic_cas64(int64 volatile *a, int64 *cmp, int64 set)
{
  int64 initial_cmp= *cmp;
  int64 initial_a= InterlockedCompareExchange64((volatile LONGLONG*)a,
                                                (LONGLONG)set,
                                                (LONGLONG)initial_cmp);
  int ret= (initial_a == initial_cmp);
  if (!ret)
    *cmp= initial_a;
  return ret;
}

static inline int my_atomic_casptr(void * volatile *a, void **cmp, void *set)
{
  void *initial_cmp= *cmp;
  void *initial_a= InterlockedCompareExchangePointer(a, set, initial_cmp);
  int ret= (initial_a == initial_cmp);
  if (!ret)
    *cmp= initial_a;
  return ret;
}

static inline int32 my_atomic_add32(int32 volatile *a, int32 v)
{
  return (int32)InterlockedExchangeAdd((volatile LONG*)a, v);
}

static inline int64 my_atomic_add64(int64 volatile *a, int64 v)
{
  return (int64)InterlockedExchangeAdd64((volatile LONGLONG*)a, (LONGLONG)v);
}

static inline int32 my_atomic_load32(int32 volatile *a)
{
  return (int32)InterlockedCompareExchange((volatile LONG *)a, 0, 0);
}

static inline int64 my_atomic_load64(int64 volatile *a)
{
  return (int64)InterlockedCompareExchange64((volatile LONGLONG *)a, 0, 0);
}

static inline void* my_atomic_loadptr(void * volatile *a)
{
  return InterlockedCompareExchangePointer(a, 0, 0);
}

static inline int32 my_atomic_fas32(int32 volatile *a, int32 v)
{
  return (int32)InterlockedExchange((volatile LONG*)a, v);
}

static inline int64 my_atomic_fas64(int64 volatile *a, int64 v)
{
  return (int64)InterlockedExchange64((volatile LONGLONG*)a, v);
}

static inline void * my_atomic_fasptr(void * volatile *a, void * v)
{
  return InterlockedExchangePointer(a, v);
}

static inline void my_atomic_store32(int32 volatile *a, int32 v)
{
  (void)InterlockedExchange((volatile LONG*)a, v);
}

static inline void my_atomic_store64(int64 volatile *a, int64 v)
{
  (void)InterlockedExchange64((volatile LONGLONG*)a, v);
}

static inline void my_atomic_storeptr(void * volatile *a, void *v)
{
  (void)InterlockedExchangePointer(a, v);
}


/*
  my_yield_processor (equivalent of x86 PAUSE instruction) should be used
  to improve performance on hyperthreaded CPUs. Intel recommends to use it in
  spin loops also on non-HT machines to reduce power consumption (see e.g
  http://softwarecommunity.intel.com/articles/eng/2004.htm)

  Running benchmarks for spinlocks implemented with InterlockedCompareExchange
  and YieldProcessor shows that much better performance is achieved by calling
  YieldProcessor in a loop - that is, yielding longer. On Intel boxes setting
  loop count in the range 200-300 brought best results.
 */
#define YIELD_LOOPS 200

static inline int my_yield_processor()
{
  int i;
  for (i=0; i<YIELD_LOOPS; i++)
  {
    YieldProcessor();
  }
  return 1;
}

#define LF_BACKOFF my_yield_processor()

#endif /* ATOMIC_MSC_INCLUDED */
