#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED | |
#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED | |
// MS compatible compilers support #pragma once | |
#if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
# pragma once | |
#endif | |
// detail/sp_counted_base_gcc_sparc.hpp - g++ on Sparc V8+ | |
// | |
// Copyright (c) 2006 Piotr Wyderski | |
// Copyright (c) 2006 Tomas Puverle | |
// Copyright (c) 2006 Peter Dimov | |
// | |
// 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 | |
// | |
// Thanks to Michael van der Westhuizen | |
#include <boost/detail/sp_typeinfo.hpp> | |
#include <inttypes.h> // int32_t | |
namespace boost | |
{ | |
namespace detail | |
{ | |
inline int32_t compare_and_swap( int32_t * dest_, int32_t compare_, int32_t swap_ ) | |
{ | |
__asm__ __volatile__( "cas [%1], %2, %0" | |
: "+r" (swap_) | |
: "r" (dest_), "r" (compare_) | |
: "memory" ); | |
return swap_; | |
} | |
inline int32_t atomic_fetch_and_add( int32_t * pw, int32_t dv ) | |
{ | |
// long r = *pw; | |
// *pw += dv; | |
// return r; | |
for( ;; ) | |
{ | |
int32_t r = *pw; | |
if( __builtin_expect((compare_and_swap(pw, r, r + dv) == r), 1) ) | |
{ | |
return r; | |
} | |
} | |
} | |
inline void atomic_increment( int32_t * pw ) | |
{ | |
atomic_fetch_and_add( pw, 1 ); | |
} | |
inline int32_t atomic_decrement( int32_t * pw ) | |
{ | |
return atomic_fetch_and_add( pw, -1 ); | |
} | |
inline int32_t atomic_conditional_increment( int32_t * pw ) | |
{ | |
// long r = *pw; | |
// if( r != 0 ) ++*pw; | |
// return r; | |
for( ;; ) | |
{ | |
int32_t r = *pw; | |
if( r == 0 ) | |
{ | |
return r; | |
} | |
if( __builtin_expect( ( compare_and_swap( pw, r, r + 1 ) == r ), 1 ) ) | |
{ | |
return r; | |
} | |
} | |
} | |
class sp_counted_base | |
{ | |
private: | |
sp_counted_base( sp_counted_base const & ); | |
sp_counted_base & operator= ( sp_counted_base const & ); | |
int32_t use_count_; // #shared | |
int32_t 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; | |
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_ ) == 1 ) | |
{ | |
dispose(); | |
weak_release(); | |
} | |
} | |
void weak_add_ref() // nothrow | |
{ | |
atomic_increment( &weak_count_ ); | |
} | |
void weak_release() // nothrow | |
{ | |
if( atomic_decrement( &weak_count_ ) == 1 ) | |
{ | |
destroy(); | |
} | |
} | |
long use_count() const // nothrow | |
{ | |
return const_cast< int32_t const volatile & >( use_count_ ); | |
} | |
}; | |
} // namespace detail | |
} // namespace boost | |
#endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_GCC_SPARC_HPP_INCLUDED |