os0atomic.h

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/** @file include/os0atomic.h
 Macros for using atomics
 
 Created 2012-09-23 Sunny Bains (Split from os0sync.h)
 *******************************************************/
 
#ifndef os0atomic_h
#define os0atomic_h
 
#include "univ.i"
 
/** barrier definitions for memory ordering */
#ifdef HAVE_IB_GCC_ATOMIC_THREAD_FENCE
#define HAVE_MEMORY_BARRIER
#define os_rmb __atomic_thread_fence(__ATOMIC_ACQUIRE)
#define os_wmb __atomic_thread_fence(__ATOMIC_RELEASE)
#define IB_MEMORY_BARRIER_STARTUP_MSG \
  "GCC builtin __atomic_thread_fence() is used for memory barrier"
 
#elif defined(HAVE_IB_GCC_SYNC_SYNCHRONISE)
#define HAVE_MEMORY_BARRIER
#define os_rmb __sync_synchronize()
#define os_wmb __sync_synchronize()
#define IB_MEMORY_BARRIER_STARTUP_MSG \
  "GCC builtin __sync_synchronize() is used for memory barrier"
 
#elif defined(HAVE_IB_MACHINE_BARRIER_SOLARIS)
#define HAVE_MEMORY_BARRIER
#include <mbarrier.h>
#define os_rmb __machine_r_barrier()
#define os_wmb __machine_w_barrier()
#define IB_MEMORY_BARRIER_STARTUP_MSG \
  "Solaris memory ordering functions are used for memory barrier"
 
#elif defined(HAVE_WINDOWS_MM_FENCE) && defined(_WIN64)
#define HAVE_MEMORY_BARRIER
#include <mmintrin.h>
#define os_rmb _mm_lfence()
#define os_wmb _mm_sfence()
#define IB_MEMORY_BARRIER_STARTUP_MSG \
  "_mm_lfence() and _mm_sfence() are used for memory barrier"
 
#else
#define os_rmb
#define os_wmb
#define IB_MEMORY_BARRIER_STARTUP_MSG "Memory barrier is not used"
#endif
 
#endif /* !os0atomic_h */