[44] | 1 | #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED |
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| 2 | #define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED |
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| 3 | |
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| 4 | // MS compatible compilers support #pragma once |
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| 5 | |
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| 6 | #if defined(_MSC_VER) && (_MSC_VER >= 1020) |
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| 7 | # pragma once |
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| 8 | #endif |
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| 9 | |
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| 10 | // detail/sp_counted_base_gcc_sparc.hpp - g++ on Sparc V8+ |
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| 11 | // |
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| 12 | // Copyright (c) 2006 Piotr Wyderski |
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| 13 | // Copyright (c) 2006 Tomas Puverle |
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| 14 | // Copyright (c) 2006 Peter Dimov |
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| 15 | // |
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| 16 | // Distributed under the Boost Software License, Version 1.0. |
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| 17 | // See accompanying file LICENSE_1_0.txt or copy at |
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| 18 | // http://www.boost.org/LICENSE_1_0.txt |
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| 19 | // |
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| 20 | // Thanks to Michael van der Westhuizen |
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| 21 | |
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| 22 | #include <boost/detail/sp_typeinfo.hpp> |
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| 23 | #include <inttypes.h> // int32_t |
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| 24 | |
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| 25 | namespace boost |
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| 26 | { |
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| 27 | |
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| 28 | namespace detail |
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| 29 | { |
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| 30 | |
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| 31 | inline int32_t compare_and_swap( int32_t * dest_, int32_t compare_, int32_t swap_ ) |
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| 32 | { |
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| 33 | __asm__ __volatile__( "cas [%1], %2, %0" |
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| 34 | : "+r" (swap_) |
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| 35 | : "r" (dest_), "r" (compare_) |
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| 36 | : "memory" ); |
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| 37 | |
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| 38 | return swap_; |
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| 39 | } |
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| 40 | |
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| 41 | inline int32_t atomic_fetch_and_add( int32_t * pw, int32_t dv ) |
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| 42 | { |
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| 43 | // long r = *pw; |
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| 44 | // *pw += dv; |
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| 45 | // return r; |
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| 46 | |
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| 47 | for( ;; ) |
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| 48 | { |
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| 49 | int32_t r = *pw; |
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| 50 | |
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| 51 | if( __builtin_expect((compare_and_swap(pw, r, r + dv) == r), 1) ) |
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| 52 | { |
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| 53 | return r; |
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| 54 | } |
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| 55 | } |
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| 56 | } |
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| 57 | |
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| 58 | inline void atomic_increment( int32_t * pw ) |
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| 59 | { |
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| 60 | atomic_fetch_and_add( pw, 1 ); |
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| 61 | } |
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| 62 | |
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| 63 | inline int32_t atomic_decrement( int32_t * pw ) |
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| 64 | { |
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| 65 | return atomic_fetch_and_add( pw, -1 ); |
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| 66 | } |
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| 67 | |
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| 68 | inline int32_t atomic_conditional_increment( int32_t * pw ) |
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| 69 | { |
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| 70 | // long r = *pw; |
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| 71 | // if( r != 0 ) ++*pw; |
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| 72 | // return r; |
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| 73 | |
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| 74 | for( ;; ) |
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| 75 | { |
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| 76 | int32_t r = *pw; |
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| 77 | |
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| 78 | if( r == 0 ) |
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| 79 | { |
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| 80 | return r; |
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| 81 | } |
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| 82 | |
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| 83 | if( __builtin_expect( ( compare_and_swap( pw, r, r + 1 ) == r ), 1 ) ) |
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| 84 | { |
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| 85 | return r; |
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| 86 | } |
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| 87 | } |
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| 88 | } |
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| 89 | |
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| 90 | class sp_counted_base |
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| 91 | { |
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| 92 | private: |
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| 93 | |
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| 94 | sp_counted_base( sp_counted_base const & ); |
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| 95 | sp_counted_base & operator= ( sp_counted_base const & ); |
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| 96 | |
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| 97 | int32_t use_count_; // #shared |
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| 98 | int32_t weak_count_; // #weak + (#shared != 0) |
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| 99 | |
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| 100 | public: |
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| 101 | |
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| 102 | sp_counted_base(): use_count_( 1 ), weak_count_( 1 ) |
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| 103 | { |
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| 104 | } |
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| 105 | |
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| 106 | virtual ~sp_counted_base() // nothrow |
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| 107 | { |
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| 108 | } |
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| 109 | |
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| 110 | // dispose() is called when use_count_ drops to zero, to release |
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| 111 | // the resources managed by *this. |
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| 112 | |
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| 113 | virtual void dispose() = 0; // nothrow |
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| 114 | |
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| 115 | // destroy() is called when weak_count_ drops to zero. |
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| 116 | |
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| 117 | virtual void destroy() // nothrow |
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| 118 | { |
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| 119 | delete this; |
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| 120 | } |
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| 121 | |
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| 122 | virtual void * get_deleter( sp_typeinfo const & ti ) = 0; |
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| 123 | |
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| 124 | void add_ref_copy() |
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| 125 | { |
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| 126 | atomic_increment( &use_count_ ); |
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| 127 | } |
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| 128 | |
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| 129 | bool add_ref_lock() // true on success |
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| 130 | { |
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| 131 | return atomic_conditional_increment( &use_count_ ) != 0; |
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| 132 | } |
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| 133 | |
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| 134 | void release() // nothrow |
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| 135 | { |
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| 136 | if( atomic_decrement( &use_count_ ) == 1 ) |
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| 137 | { |
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| 138 | dispose(); |
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| 139 | weak_release(); |
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| 140 | } |
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| 141 | } |
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| 142 | |
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| 143 | void weak_add_ref() // nothrow |
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| 144 | { |
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| 145 | atomic_increment( &weak_count_ ); |
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| 146 | } |
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| 147 | |
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| 148 | void weak_release() // nothrow |
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| 149 | { |
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| 150 | if( atomic_decrement( &weak_count_ ) == 1 ) |
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| 151 | { |
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| 152 | destroy(); |
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| 153 | } |
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| 154 | } |
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| 155 | |
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| 156 | long use_count() const // nothrow |
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| 157 | { |
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| 158 | return const_cast< int32_t const volatile & >( use_count_ ); |
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| 159 | } |
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| 160 | }; |
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| 161 | |
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| 162 | } // namespace detail |
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| 163 | |
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| 164 | } // namespace boost |
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| 165 | |
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| 166 | #endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED |
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