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#ifndef BOOST_DETAIL_SP_COUNTED_BASE_GCC_MIPS_HPP_INCLUDED
#define BOOST_DETAIL_SP_COUNTED_BASE_GCC_MIPS_HPP_INCLUDED
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
//
// detail/sp_counted_base_gcc_mips.hpp - g++ on MIPS
//
// Copyright (c) 2009, Spirent Communications, Inc.
//
// 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>
namespace boost
{
namespace detail
{
inline void atomic_increment( int * pw )
{
// ++*pw;
int tmp;
__asm__ __volatile__
(
"0:\n\t"
".set push\n\t"
".set mips2\n\t"
"ll %0, %1\n\t"
"addiu %0, 1\n\t"
"sc %0, %1\n\t"
".set pop\n\t"
"beqz %0, 0b":
"=&r"( tmp ), "=m"( *pw ):
"m"( *pw )
);
}
inline int atomic_decrement( int * pw )
{
// return --*pw;
int rv, tmp;
__asm__ __volatile__
(
"0:\n\t"
".set push\n\t"
".set mips2\n\t"
"ll %1, %2\n\t"
"addiu %0, %1, -1\n\t"
"sc %0, %2\n\t"
".set pop\n\t"
"beqz %0, 0b\n\t"
"addiu %0, %1, -1":
"=&r"( rv ), "=&r"( tmp ), "=m"( *pw ):
"m"( *pw ):
"memory"
);
return rv;
}
inline int atomic_conditional_increment( int * pw )
{
// if( *pw != 0 ) ++*pw;
// return *pw;
int rv, tmp;
__asm__ __volatile__
(
"0:\n\t"
".set push\n\t"
".set mips2\n\t"
"ll %0, %2\n\t"
"beqz %0, 1f\n\t"
"addiu %1, %0, 1\n\t"
"sc %1, %2\n\t"
".set pop\n\t"
"beqz %1, 0b\n\t"
"addiu %0, %0, 1\n\t"
"1:":
"=&r"( rv ), "=&r"( tmp ), "=m"( *pw ):
"m"( *pw ):
"memory"
);
return rv;
}
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_ );
}
};
} // namespace detail
} // namespace boost
#endif // #ifndef BOOST_DETAIL_SP_COUNTED_BASE_GCC_MIPS_HPP_INCLUDED
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