152 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			152 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
|   | #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_ACC_IA64_HPP_INCLUDED | ||
|  | #define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_ACC_IA64_HPP_INCLUDED | ||
|  | 
 | ||
|  | // | ||
|  | //  detail/sp_counted_base_acc_ia64.hpp - aC++ on HP-UX IA64 | ||
|  | // | ||
|  | //  Copyright 2007 Baruch Zilber | ||
|  | //  Copyright 2007 Boris Gubenko | ||
|  | // | ||
|  | //  Distributed under the Boost Software License, Version 1.0. (See | ||
|  | //  accompanying file LICENSE_1_0.txt or copy at | ||
|  | //  http://www.boost.org/LICENSE_1_0.txt) | ||
|  | // | ||
|  | // | ||
|  | //  Lock-free algorithm by Alexander Terekhov | ||
|  | // | ||
|  | 
 | ||
|  | #include <boost/detail/sp_typeinfo.hpp> | ||
|  | #include <machine/sys/inline.h> | ||
|  | 
 | ||
|  | namespace boost | ||
|  | { | ||
|  | 
 | ||
|  | namespace detail | ||
|  | { | ||
|  | 
 | ||
|  | inline void atomic_increment( int * pw ) | ||
|  | { | ||
|  |     // ++*pw; | ||
|  | 
 | ||
|  |     _Asm_fetchadd(_FASZ_W, _SEM_REL, pw, +1, _LDHINT_NONE); | ||
|  | }  | ||
|  | 
 | ||
|  | inline int atomic_decrement( int * pw ) | ||
|  | { | ||
|  |     // return --*pw; | ||
|  | 
 | ||
|  |     int r = static_cast<int>(_Asm_fetchadd(_FASZ_W, _SEM_REL, pw, -1, _LDHINT_NONE)); | ||
|  |     if (1 == r) | ||
|  |     { | ||
|  |         _Asm_mf(); | ||
|  |     } | ||
|  |      | ||
|  |     return r - 1; | ||
|  | } | ||
|  | 
 | ||
|  | inline int atomic_conditional_increment( int * pw ) | ||
|  | { | ||
|  |     // if( *pw != 0 ) ++*pw; | ||
|  |     // return *pw; | ||
|  | 
 | ||
|  |     int v = *pw; | ||
|  |      | ||
|  |     for (;;) | ||
|  |     { | ||
|  |         if (0 == v) | ||
|  |         { | ||
|  |             return 0; | ||
|  |         } | ||
|  |          | ||
|  |         _Asm_mov_to_ar(_AREG_CCV, | ||
|  |                        v, | ||
|  |                        (_UP_CALL_FENCE | _UP_SYS_FENCE | _DOWN_CALL_FENCE | _DOWN_SYS_FENCE)); | ||
|  |         int r = static_cast<int>(_Asm_cmpxchg(_SZ_W, _SEM_ACQ, pw, v + 1, _LDHINT_NONE)); | ||
|  |         if (r == v) | ||
|  |         { | ||
|  |             return r + 1; | ||
|  |         } | ||
|  |          | ||
|  |         v = r; | ||
|  |     } | ||
|  | } | ||
|  | 
 | ||
|  | class sp_counted_base | ||
|  | { | ||
|  | private: | ||
|  | 
 | ||
|  |     sp_counted_base( sp_counted_base const & ); | ||
|  |     sp_counted_base & operator= ( sp_counted_base const & ); | ||
|  | 
 | ||
|  |     int use_count_;        // #shared | ||
|  |     int weak_count_;       // #weak + (#shared != 0) | ||
|  | 
 | ||
|  | public: | ||
|  | 
 | ||
|  |     sp_counted_base(): use_count_( 1 ), weak_count_( 1 ) | ||
|  |     { | ||
|  |     } | ||
|  | 
 | ||
|  |     virtual ~sp_counted_base() // nothrow | ||
|  |     { | ||
|  |     } | ||
|  | 
 | ||
|  |     // dispose() is called when use_count_ drops to zero, to release | ||
|  |     // the resources managed by *this. | ||
|  | 
 | ||
|  |     virtual void dispose() = 0; // nothrow | ||
|  | 
 | ||
|  |     // destroy() is called when weak_count_ drops to zero. | ||
|  | 
 | ||
|  |     virtual void destroy() // nothrow | ||
|  |     { | ||
|  |         delete this; | ||
|  |     } | ||
|  | 
 | ||
|  |     virtual void * get_deleter( sp_typeinfo const & ti ) = 0; | ||
|  |     virtual void * get_untyped_deleter() = 0; | ||
|  | 
 | ||
|  |     void add_ref_copy() | ||
|  |     { | ||
|  |         atomic_increment( &use_count_ ); | ||
|  |     } | ||
|  | 
 | ||
|  |     bool add_ref_lock() // true on success | ||
|  |     { | ||
|  |         return atomic_conditional_increment( &use_count_ ) != 0; | ||
|  |     } | ||
|  | 
 | ||
|  |     void release() // nothrow | ||
|  |     { | ||
|  |         if( atomic_decrement( &use_count_ ) == 0 ) | ||
|  |         { | ||
|  |             dispose(); | ||
|  |             weak_release(); | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     void weak_add_ref() // nothrow | ||
|  |     { | ||
|  |         atomic_increment( &weak_count_ ); | ||
|  |     } | ||
|  | 
 | ||
|  |     void weak_release() // nothrow | ||
|  |     { | ||
|  |         if( atomic_decrement( &weak_count_ ) == 0 ) | ||
|  |         { | ||
|  |             destroy(); | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     long use_count() const // nothrow | ||
|  |     { | ||
|  |         return static_cast<int const volatile &>( use_count_ ); // TODO use ld.acq here | ||
|  |     } | ||
|  | }; | ||
|  | 
 | ||
|  | } // namespace detail | ||
|  | 
 | ||
|  | } // namespace boost | ||
|  | 
 | ||
|  | #endif  // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_ACC_IA64_HPP_INCLUDED |