Drizzled Public API Documentation

gcc_traits.h
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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4  * Copyright (C) 2009 Sun Microsystems, Inc.
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13  * GNU General Public License for more details.
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17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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19 
20 #pragma once
21 
22 namespace drizzled {
23 namespace internal {
24 
25 template<typename T, typename D>
27 {
28 
29 public:
30  typedef T value_type;
31 
32  gcc_traits() {}
33 
34  inline value_type add_and_fetch(volatile value_type *value, D addend )
35  {
36  return __sync_add_and_fetch(value, addend);
37  }
38 
39  inline value_type fetch_and_add(volatile value_type *value, D addend )
40  {
41  return __sync_fetch_and_add(value, addend);
42  }
43 
44  inline value_type fetch_and_increment(volatile value_type *value)
45  {
46  return __sync_fetch_and_add(value, 1);
47  }
48 
49  inline value_type fetch_and_decrement(volatile value_type *value)
50  {
51  return __sync_fetch_and_sub(value, 1);
52  }
53 
54  inline value_type fetch_and_store(volatile value_type *value,
55  value_type new_value)
56  {
57  return __sync_lock_test_and_set(value, new_value);
58  }
59 
60  inline bool compare_and_swap(volatile value_type *value,
61  value_type new_value,
62  value_type comparand )
63  {
64  return __sync_bool_compare_and_swap(value, comparand, new_value);
65  }
66 
67  inline value_type fetch(const volatile value_type *value) const volatile
68  {
69  /*
70  * This is necessary to ensure memory barriers are respected when
71  * simply returning the value pointed at. However, this does not
72  * compile on ICC.
73  *
74  * @todo
75  *
76  * Look at how to rewrite the below to something that ICC feels is
77  * OK and yet respects memory barriers.
78  */
79  return __sync_fetch_and_add(const_cast<value_type *>(value), 0);
80  }
81 
82  inline value_type store_with_release(volatile value_type *value,
83  value_type new_value)
84  {
85  *value= new_value;
86  return *value;
87  }
88 
89 }; /* gcc_traits */
90 
91 
92 } /* namespace internal */
93 } /* namespace drizzled */
94