hotspot/src/os_cpu/linux_sparc/vm/orderAccess_linux_sparc.inline.hpp
author dholmes
Tue, 03 Mar 2015 19:20:26 -0500
changeset 29456 cc1c5203e60d
parent 25715 d5a8dbdc5150
permissions -rw-r--r--
7143664: Clean up OrderAccess implementations and usage Summary: Clarify and correct the abstract model for memory barriers provided by the orderAccess class. Refactor the implementations using template specialization to allow the bulk of the code to be shared, with platform specific customizations applied as needed. Reviewed-by: acorn, dcubed, dholmes, dlong, goetz, kbarrett, sgehwolf Contributed-by: Erik Osterlund <erik.osterlund@lnu.se>

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#ifndef OS_CPU_LINUX_SPARC_VM_ORDERACCESS_LINUX_SPARC_INLINE_HPP
#define OS_CPU_LINUX_SPARC_VM_ORDERACCESS_LINUX_SPARC_INLINE_HPP

#include "runtime/orderAccess.hpp"

// Implementation of class OrderAccess.

// A compiler barrier, forcing the C++ compiler to invalidate all memory assumptions
static inline void compiler_barrier() {
  __asm__ volatile ("" : : : "memory");
}

// Assume TSO.

inline void OrderAccess::loadload()   { compiler_barrier(); }
inline void OrderAccess::storestore() { compiler_barrier(); }
inline void OrderAccess::loadstore()  { compiler_barrier(); }
inline void OrderAccess::storeload()  { fence();            }

inline void OrderAccess::acquire()    { compiler_barrier(); }
inline void OrderAccess::release()    { compiler_barrier(); }

inline void OrderAccess::fence() {
  __asm__ volatile ("membar  #StoreLoad" : : : "memory");
}

#define VM_HAS_GENERALIZED_ORDER_ACCESS 1

#endif // OS_CPU_LINUX_SPARC_VM_ORDERACCESS_LINUX_SPARC_INLINE_HPP