/*
    Copyright 2005-2012 Intel Corporation.  All Rights Reserved.

    This file is part of Threading Building Blocks.

    Threading Building Blocks is free software; you can redistribute it
    and/or modify it under the terms of the GNU General Public License
    version 2 as published by the Free Software Foundation.

    Threading Building Blocks 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 for more details.

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

    As a special exception, you may use this file as part of a free software
    library without restriction.  Specifically, if other files instantiate
    templates or use macros or inline functions from this file, or you compile
    this file and link it with other files to produce an executable, this
    file does not by itself cause the resulting executable to be covered by
    the GNU General Public License.  This exception does not however
    invalidate any other reasons why the executable file might be covered by
    the GNU General Public License.
*/

#if !defined(__TBB_machine_H) || defined(__TBB_machine_gcc_generic_H)
#error Do not #include this internal file directly; use public TBB headers instead.
#endif

#define __TBB_machine_gcc_generic_H

#include <stdint.h>
#include <unistd.h>

#define __TBB_WORDSIZE      __SIZEOF_POINTER__

#if __TBB_GCC_64BIT_ATOMIC_BUILTINS_BROKEN
    #define __TBB_64BIT_ATOMICS 0
#endif

/** FPU control setting not available for non-Intel architectures on Android **/
#if __ANDROID__ && __TBB_generic_arch 
    #define __TBB_CPU_CTL_ENV_PRESENT 0
#endif

#ifdef __BYTE_ORDER__
    #if __BYTE_ORDER__==__ORDER_BIG_ENDIAN__
        #define __TBB_BIG_ENDIAN    1
    #elif __BYTE_ORDER__==__ORDER_LITTLE_ENDIAN__
        #define __TBB_BIG_ENDIAN    0
    #elif __BYTE_ORDER__==__ORDER_PDP_ENDIAN__
        #define __TBB_BIG_ENDIAN -1 // not currently supported
    #endif
#endif

/** As this generic implementation has absolutely no information about underlying
    hardware, its performance most likely will be sub-optimal because of full memory
    fence usages where a more lightweight synchronization means (or none at all)
    could suffice. Thus if you use this header to enable TBB on a new platform,
    consider forking it and relaxing below helpers as appropriate. **/
#define __TBB_acquire_consistency_helper()  __sync_synchronize()
#define __TBB_release_consistency_helper()  __sync_synchronize()
#define __TBB_full_memory_fence()           __sync_synchronize()
#define __TBB_control_consistency_helper()  __sync_synchronize()

#define __TBB_MACHINE_DEFINE_ATOMICS(S,T)                                                         \
inline T __TBB_machine_cmpswp##S( volatile void *ptr, T value, T comparand ) {                    \
    return __sync_val_compare_and_swap(reinterpret_cast<volatile T *>(ptr),comparand,value);      \
}                                                                                                 \
                                                                                                  \
inline T __TBB_machine_fetchadd##S( volatile void *ptr, T value ) {                               \
    return __sync_fetch_and_add(reinterpret_cast<volatile T *>(ptr),value);                       \
}                                                                                                 \

__TBB_MACHINE_DEFINE_ATOMICS(1,int8_t)
__TBB_MACHINE_DEFINE_ATOMICS(2,int16_t)
__TBB_MACHINE_DEFINE_ATOMICS(4,int32_t)
__TBB_MACHINE_DEFINE_ATOMICS(8,int64_t)

#undef __TBB_MACHINE_DEFINE_ATOMICS

namespace tbb{ namespace internal { namespace gcc_builtins {
    inline int clz(unsigned int x){ return __builtin_clz(x);};
    inline int clz(unsigned long int x){ return __builtin_clzl(x);};
    inline int clz(unsigned long long int x){ return __builtin_clzll(x);};
}}}
//gcc __builtin_clz builtin count _number_ of leading zeroes
static inline intptr_t __TBB_machine_lg( uintptr_t x ) {
    return sizeof(x)*8 - tbb::internal::gcc_builtins::clz(x) -1 ;
}

static inline void __TBB_machine_or( volatile void *ptr, uintptr_t addend ) {
    __sync_fetch_and_or(reinterpret_cast<volatile uintptr_t *>(ptr),addend);
}

static inline void __TBB_machine_and( volatile void *ptr, uintptr_t addend ) {
    __sync_fetch_and_and(reinterpret_cast<volatile uintptr_t *>(ptr),addend);
}


typedef unsigned char __TBB_Flag;

typedef __TBB_atomic __TBB_Flag __TBB_atomic_flag;

inline bool __TBB_machine_try_lock_byte( __TBB_atomic_flag &flag ) {
    return __sync_lock_test_and_set(&flag,1)==0;
}

inline void __TBB_machine_unlock_byte( __TBB_atomic_flag &flag , __TBB_Flag) {
    __sync_lock_release(&flag);
}

// Machine specific atomic operations
#define __TBB_AtomicOR(P,V)     __TBB_machine_or(P,V)
#define __TBB_AtomicAND(P,V)    __TBB_machine_and(P,V)

#define __TBB_TryLockByte   __TBB_machine_try_lock_byte
#define __TBB_UnlockByte    __TBB_machine_unlock_byte

// Definition of other functions
#define __TBB_Log2(V)           __TBB_machine_lg(V)

#define __TBB_USE_GENERIC_FETCH_STORE                       1
#define __TBB_USE_GENERIC_HALF_FENCED_LOAD_STORE            1
#define __TBB_USE_GENERIC_RELAXED_LOAD_STORE                1
#define __TBB_USE_GENERIC_SEQUENTIAL_CONSISTENCY_LOAD_STORE 1

#if __TBB_WORDSIZE==4
    #define __TBB_USE_GENERIC_DWORD_LOAD_STORE              1
#endif
