src/hotspot/os_cpu/linux_zero/atomic_linux_zero.hpp

rev 49986 : 8202080: Introduce ordering semantics for Atomic::add and other RMW atomics
Reviewed-by: lucy, rehn, dholmes

*** 1,7 ****
  /*
!  * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
   * Copyright 2007, 2008, 2011, 2015, Red Hat, Inc.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
--- 1,7 ----
  /*
!  * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
   * Copyright 2007, 2008, 2011, 2015, Red Hat, Inc.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
*** 33,66 ****
  template<size_t byte_size>
  struct Atomic::PlatformAdd
    : Atomic::AddAndFetch<Atomic::PlatformAdd<byte_size> >
  {
    template<typename I, typename D>
!   D add_and_fetch(I add_value, D volatile* dest) const;
  };
  
  template<>
  template<typename I, typename D>
! inline D Atomic::PlatformAdd<4>::add_and_fetch(I add_value, D volatile* dest) const {
    STATIC_ASSERT(4 == sizeof(I));
    STATIC_ASSERT(4 == sizeof(D));
  
    return __sync_add_and_fetch(dest, add_value);
  }
  
  template<>
  template<typename I, typename D>
! inline D Atomic::PlatformAdd<8>::add_and_fetch(I add_value, D volatile* dest) const {
    STATIC_ASSERT(8 == sizeof(I));
    STATIC_ASSERT(8 == sizeof(D));
    return __sync_add_and_fetch(dest, add_value);
  }
  
  template<>
  template<typename T>
  inline T Atomic::PlatformXchg<4>::operator()(T exchange_value,
!                                              T volatile* dest) const {
    STATIC_ASSERT(4 == sizeof(T));
    // __sync_lock_test_and_set is a bizarrely named atomic exchange
    // operation.  Note that some platforms only support this with the
    // limitation that the only valid value to store is the immediate
    // constant 1.  There is a test for this in JNI_CreateJavaVM().
--- 33,69 ----
  template<size_t byte_size>
  struct Atomic::PlatformAdd
    : Atomic::AddAndFetch<Atomic::PlatformAdd<byte_size> >
  {
    template<typename I, typename D>
!   D add_and_fetch(I add_value, D volatile* dest, atomic_memory_order order) const;
  };
  
  template<>
  template<typename I, typename D>
! inline D Atomic::PlatformAdd<4>::add_and_fetch(I add_value, D volatile* dest,
!                                                atomic_memory_order order) const {
    STATIC_ASSERT(4 == sizeof(I));
    STATIC_ASSERT(4 == sizeof(D));
  
    return __sync_add_and_fetch(dest, add_value);
  }
  
  template<>
  template<typename I, typename D>
! inline D Atomic::PlatformAdd<8>::add_and_fetch(I add_value, D volatile* dest,
!                                                atomic_memory_order order) const {
    STATIC_ASSERT(8 == sizeof(I));
    STATIC_ASSERT(8 == sizeof(D));
    return __sync_add_and_fetch(dest, add_value);
  }
  
  template<>
  template<typename T>
  inline T Atomic::PlatformXchg<4>::operator()(T exchange_value,
!                                              T volatile* dest,
!                                              atomic_memory_order order) const {
    STATIC_ASSERT(4 == sizeof(T));
    // __sync_lock_test_and_set is a bizarrely named atomic exchange
    // operation.  Note that some platforms only support this with the
    // limitation that the only valid value to store is the immediate
    // constant 1.  There is a test for this in JNI_CreateJavaVM().
*** 74,84 ****
  }
  
  template<>
  template<typename T>
  inline T Atomic::PlatformXchg<8>::operator()(T exchange_value,
!                                              T volatile* dest) const {
    STATIC_ASSERT(8 == sizeof(T));
    T result = __sync_lock_test_and_set (dest, exchange_value);
    __sync_synchronize();
    return result;
  }
--- 77,88 ----
  }
  
  template<>
  template<typename T>
  inline T Atomic::PlatformXchg<8>::operator()(T exchange_value,
!                                              T volatile* dest,
!                                              atomic_memory_order order) const {
    STATIC_ASSERT(8 == sizeof(T));
    T result = __sync_lock_test_and_set (dest, exchange_value);
    __sync_synchronize();
    return result;
  }
*** 90,110 ****
  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));
    return __sync_val_compare_and_swap(dest, compare_value, exchange_value);
  }
  
  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));
    return __sync_val_compare_and_swap(dest, compare_value, exchange_value);
  }
  
  template<>
--- 94,114 ----
  template<>
  template<typename T>
  inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value,
                                                  T volatile* dest,
                                                  T compare_value,
!                                                 atomic_memory_order order) const {
    STATIC_ASSERT(4 == sizeof(T));
    return __sync_val_compare_and_swap(dest, compare_value, exchange_value);
  }
  
  template<>
  template<typename T>
  inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value,
                                                  T volatile* dest,
                                                  T compare_value,
!                                                 atomic_memory_order order) const {
    STATIC_ASSERT(8 == sizeof(T));
    return __sync_val_compare_and_swap(dest, compare_value, exchange_value);
  }
  
  template<>