hotspot/src/os_cpu/solaris_sparc/vm/atomic_solaris_sparc.hpp
author eosterlund
Mon, 28 Aug 2017 13:31:20 +0200
changeset 46993 dd0f91c85ffc
parent 46958 a13bd8c6b7a2
permissions -rw-r--r--
8186476: Generalize Atomic::add with templates Reviewed-by: aph, dholmes Contributed-by: kim.barrett@oracle.com

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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#ifndef OS_CPU_SOLARIS_SPARC_VM_ATOMIC_SOLARIS_SPARC_HPP
#define OS_CPU_SOLARIS_SPARC_VM_ATOMIC_SOLARIS_SPARC_HPP

// Implementation of class atomic

inline void Atomic::store    (jbyte    store_value, jbyte*    dest) { *dest = store_value; }
inline void Atomic::store    (jshort   store_value, jshort*   dest) { *dest = store_value; }
inline void Atomic::store    (jint     store_value, jint*     dest) { *dest = store_value; }
inline void Atomic::store_ptr(intptr_t store_value, intptr_t* dest) { *dest = store_value; }
inline void Atomic::store_ptr(void*    store_value, void*     dest) { *(void**)dest = store_value; }

inline void Atomic::store    (jbyte    store_value, volatile jbyte*    dest) { *dest = store_value; }
inline void Atomic::store    (jshort   store_value, volatile jshort*   dest) { *dest = store_value; }
inline void Atomic::store    (jint     store_value, volatile jint*     dest) { *dest = store_value; }
inline void Atomic::store_ptr(intptr_t store_value, volatile intptr_t* dest) { *dest = store_value; }
inline void Atomic::store_ptr(void*    store_value, volatile void*     dest) { *(void* volatile *)dest = store_value; }

inline void Atomic::inc    (volatile jint*     dest) { (void)add    (1, dest); }
inline void Atomic::inc_ptr(volatile intptr_t* dest) { (void)add_ptr(1, dest); }
inline void Atomic::inc_ptr(volatile void*     dest) { (void)add_ptr(1, dest); }

inline void Atomic::dec    (volatile jint*     dest) { (void)add    (-1, dest); }
inline void Atomic::dec_ptr(volatile intptr_t* dest) { (void)add_ptr(-1, dest); }
inline void Atomic::dec_ptr(volatile void*     dest) { (void)add_ptr(-1, dest); }


inline void Atomic::store(jlong store_value, jlong* dest) { *dest = store_value; }
inline void Atomic::store(jlong store_value, volatile jlong* dest) { *dest = store_value; }
inline jlong Atomic::load(const volatile jlong* src) { return *src; }


// This is the interface to the atomic instructions in solaris_sparc.il.
// It's very messy because we need to support v8 and these instructions
// are illegal there.  When sparc v8 is dropped, we can drop out lots of
// this code.  Also compiler2 does not support v8 so the conditional code
// omits the instruction set check.

extern "C" jint     _Atomic_swap32(jint     exchange_value, volatile jint*     dest);
extern "C" intptr_t _Atomic_swap64(intptr_t exchange_value, volatile intptr_t* dest);

// Implement ADD using a CAS loop.
template<size_t byte_size>
struct Atomic::PlatformAdd VALUE_OBJ_CLASS_SPEC {
  template<typename I, typename D>
  inline D operator()(I add_value, D volatile* dest) const {
    D old_value = *dest;
    while (true) {
      D new_value = old_value + add_value;
      D result = cmpxchg(new_value, dest, old_value);
      if (result == old_value) break;
      old_value = result;
    }
    return old_value + add_value;
  }
};

inline jint     Atomic::xchg    (jint     exchange_value, volatile jint*     dest) {
  return _Atomic_swap32(exchange_value, dest);
}

inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) {
  return _Atomic_swap64(exchange_value, dest);
}

inline void*    Atomic::xchg_ptr(void*    exchange_value, volatile void*     dest) {
  return (void*)xchg_ptr((intptr_t)exchange_value, (volatile intptr_t*)dest);
}

// No direct support for cmpxchg of bytes; emulate using int.
template<>
struct Atomic::PlatformCmpxchg<1> : Atomic::CmpxchgByteUsingInt {};

template<>
template<typename T>
inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
                                                T volatile* dest,
                                                T compare_value,
                                                cmpxchg_memory_order order) const {
  STATIC_ASSERT(4 == sizeof(T));
  T rv;
  __asm__ volatile(
    " cas    [%2], %3, %0"
    : "=r" (rv)
    : "0" (exchange_value), "r" (dest), "r" (compare_value)
    : "memory");
  return rv;
}

template<>
template<typename T>
inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
                                                T volatile* dest,
                                                T compare_value,
                                                cmpxchg_memory_order order) const {
  STATIC_ASSERT(8 == sizeof(T));
  T rv;
  __asm__ volatile(
    " casx   [%2], %3, %0"
    : "=r" (rv)
    : "0" (exchange_value), "r" (dest), "r" (compare_value)
    : "memory");
  return rv;
}

#endif // OS_CPU_SOLARIS_SPARC_VM_ATOMIC_SOLARIS_SPARC_HPP