/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2013 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2011      Sandia National Laboratories. All rights reserved.
 * Copyright (c) 2014-2016 Los Alamos National Security, LLC. All rights
 *                         reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */

#ifndef OPAL_SYS_ARCH_ATOMIC_H
#define OPAL_SYS_ARCH_ATOMIC_H 1

#include <stdbool.h>

/**********************************************************************
 *
 * Memory Barriers
 *
 *********************************************************************/
#define OPAL_HAVE_ATOMIC_MEM_BARRIER 1

#define OPAL_HAVE_ATOMIC_MATH_32 1
#define OPAL_HAVE_ATOMIC_CMPSET_32 1
#define OPAL_HAVE_ATOMIC_ADD_32 1
#define OPAL_HAVE_ATOMIC_SUB_32 1
#define OPAL_HAVE_ATOMIC_SWAP_32 1
#define OPAL_HAVE_ATOMIC_MATH_64 1
#define OPAL_HAVE_ATOMIC_CMPSET_64 1
#define OPAL_HAVE_ATOMIC_ADD_64 1
#define OPAL_HAVE_ATOMIC_SUB_64 1
#define OPAL_HAVE_ATOMIC_SWAP_64 1


static inline void opal_atomic_mb(void)
{
    __atomic_thread_fence (__ATOMIC_SEQ_CST);
}

static inline void opal_atomic_rmb(void)
{
    __atomic_thread_fence (__ATOMIC_ACQUIRE);
}

static inline void opal_atomic_wmb(void)
{
    __atomic_thread_fence (__ATOMIC_RELEASE);
}

#define MB() opal_atomic_mb()

/**********************************************************************
 *
 * Atomic math operations
 *
 *********************************************************************/

static inline int opal_atomic_cmpset_acq_32( volatile int32_t *addr,
                                             int32_t oldval, int32_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
}


static inline int opal_atomic_cmpset_rel_32( volatile int32_t *addr,
                                             int32_t oldval, int32_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_RELEASE, __ATOMIC_RELAXED);
}

static inline int opal_atomic_cmpset_32( volatile int32_t *addr,
                                         int32_t oldval, int32_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
}

static inline int32_t opal_atomic_swap_32 (volatile int32_t *addr, int32_t newval)
{
    int32_t oldval;
    __atomic_exchange (addr, &newval, &oldval, __ATOMIC_RELAXED);
    return oldval;
}

static inline int32_t opal_atomic_add_32(volatile int32_t *addr, int32_t delta)
{
    return __atomic_add_fetch (addr, delta, __ATOMIC_RELAXED);
}

static inline int32_t opal_atomic_sub_32(volatile int32_t *addr, int32_t delta)
{
    return __atomic_sub_fetch (addr, delta, __ATOMIC_RELAXED);
}

static inline int opal_atomic_cmpset_acq_64( volatile int64_t *addr,
                                             int64_t oldval, int64_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
}

static inline int opal_atomic_cmpset_rel_64( volatile int64_t *addr,
                                             int64_t oldval, int64_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_RELEASE, __ATOMIC_RELAXED);
}


static inline int opal_atomic_cmpset_64( volatile int64_t *addr,
                                         int64_t oldval, int64_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
}

static inline int64_t opal_atomic_swap_64 (volatile int64_t *addr, int64_t newval)
{
    int64_t oldval;
    __atomic_exchange (addr, &newval, &oldval, __ATOMIC_RELAXED);
    return oldval;
}

static inline int64_t opal_atomic_add_64(volatile int64_t *addr, int64_t delta)
{
    return __atomic_add_fetch (addr, delta, __ATOMIC_RELAXED);
}

static inline int64_t opal_atomic_sub_64(volatile int64_t *addr, int64_t delta)
{
    return __atomic_sub_fetch (addr, delta, __ATOMIC_RELAXED);
}

#if OPAL_HAVE_GCC_BUILTIN_CSWAP_INT128

#define OPAL_HAVE_ATOMIC_CMPSET_128 1

static inline int opal_atomic_cmpset_128 (volatile opal_int128_t *addr,
                                          opal_int128_t oldval, opal_int128_t newval)
{
    return __atomic_compare_exchange_n (addr, &oldval, newval, false,
                                        __ATOMIC_ACQUIRE, __ATOMIC_RELAXED);
}

#elif defined(OPAL_HAVE_SYNC_BUILTIN_CSWAP_INT128) && OPAL_HAVE_SYNC_BUILTIN_CSWAP_INT128

#define OPAL_HAVE_ATOMIC_CMPSET_128 1

/* __atomic version is not lock-free so use legacy __sync version */

static inline int opal_atomic_cmpset_128 (volatile opal_int128_t *addr,
                                          opal_int128_t oldval, opal_int128_t newval)
{
    return __sync_bool_compare_and_swap (addr, oldval, newval);
}

#endif

#if defined(__HLE__)

#include <immintrin.h>

#define OPAL_HAVE_ATOMIC_SPINLOCKS 1

static inline void opal_atomic_init (opal_atomic_lock_t* lock, int32_t value)
{
   lock->u.lock = value;
}

static inline int opal_atomic_trylock(opal_atomic_lock_t *lock)
{
    int ret = __atomic_exchange_n (&lock->u.lock, OPAL_ATOMIC_LOCKED,
                                   __ATOMIC_ACQUIRE | __ATOMIC_HLE_ACQUIRE);
    if (OPAL_ATOMIC_LOCKED == ret) {
        /* abort the transaction */
        _mm_pause ();
        return 1;
    }

    return 0;
}

static inline void opal_atomic_lock (opal_atomic_lock_t *lock)
{
    while (OPAL_ATOMIC_LOCKED == __atomic_exchange_n (&lock->u.lock, OPAL_ATOMIC_LOCKED,
                                                      __ATOMIC_ACQUIRE | __ATOMIC_HLE_ACQUIRE)) {
        /* abort the transaction */
        _mm_pause ();
    }
}

static inline void opal_atomic_unlock (opal_atomic_lock_t *lock)
{
    __atomic_store_n (&lock->u.lock, OPAL_ATOMIC_UNLOCKED,
                       __ATOMIC_RELEASE | __ATOMIC_HLE_RELEASE);
}

#endif

#endif /* ! OPAL_SYS_ARCH_ATOMIC_H */
