atomic.h

説明を見る。

// -*- C++ -*-
#ifndef COIL_ATOMIC_H

#ifdef COIL_HAS_ATOMIC_OP

#include <bits/atomicity.h>

#define COIL_USES_ATOMIC_OP
#define atomic_add(x, y) __gnu_cxx::__atomic_add(x, y)
#define atomic_incr(x)   __gnu_cxx::__atomic_add(x, 1)
#define atomic_decr(x)   __gnu_cxx::__atomic_add(x, -1)
#define atomic_exchange_add(x, y) __gnu_cxx::__exchange_and_add(x, y)
#else

#include <coil/Mutex.h>
#include <coil/Guard.h>
#define COIL_USES_ATOMIC_OP coil::Mutex __mutex;

#define atomic_add(x, y)                        \
  {                                             \
    coil::Guard<coil::Mutex> guard(__mutex);    \
    *x = *x + y;                                \
  }

#define atomic_incr(x)                          \
  {                                             \
    coil::Guard<coil::Mutex> guard(__mutex);    \
    ++(*x);                                     \
  }

#define atomic_decr(x)                          \
  {                                             \
    coil::Guard<coil::Mutex> guard(__mutex);    \
    --(*x);                                     \
  }

int exchange_add(int* x, int y, coil::Mutex* mutex)
{
  coil::Guard<coil::Mutex> guard(*mutex);
  int tmp(*x);
  *x = *x + y;
  return tmp;
}

#define atomic_exchange_add(x, y)               \
  exchange_add(x, y, &__mutex)
    
#endif // COIL_HAS_ATOMIC_ADD
#endif // COIL_ATOMIC_H

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