pcsx2/common/include/Utilities/TlsVariable.inl

126 lines
3.9 KiB
C++

/* PCSX2 - PS2 Emulator for PCs
* Copyright (C) 2002-2010 PCSX2 Dev Team
*
* PCSX2 is free software: you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* PCSX2 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with PCSX2.
* If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "Threading.h"
#if PCSX2_THREAD_LOCAL
# define DeclareTls(x) __threadlocal x
#else
# define DeclareTls(x) Threading::TlsVariable<x>
#endif
namespace Threading
{
// --------------------------------------------------------------------------------------
// TlsVariable - Thread local storage
// --------------------------------------------------------------------------------------
// Wrapper class for pthread_getspecific, which is pthreads language for "thread local
// storage." This class enables code to act as a drop-in replacement for compiler-native
// thread local storage (typically specified via __threadlocal). Mac OS/X (Darwin) does
// not have TLS, which is the main reason for this class existing.
//
// Performance considerations: While certainly convenient, performance of this class can
// be sub-optimal when the operator overloads are used, since each one will most likely
// result in repeated calls to pthread_getspecific. (if the function inlines then it
// should actually optimize well enough, but I doubt it does).
//
template< typename T >
class TlsVariable
{
DeclareNoncopyableObject(TlsVariable);
protected:
pthread_key_t m_thread_key;
T m_initval;
public:
TlsVariable();
TlsVariable( T initval );
virtual ~TlsVariable() throw();
T* GetPtr() const;
T& GetRef() const { return *GetPtr(); }
TlsVariable& operator=( const T& src )
{
GetRef() = src;
return *this;
}
bool operator==( const T& src ) const { return GetRef() == src; }
bool operator!=( const T& src ) const { return GetRef() != src; }
bool operator>( const T& src ) const { return GetRef() > src; }
bool operator<( const T& src ) const { return GetRef() < src; }
bool operator>=( const T& src ) const { return GetRef() >= src; }
bool operator<=( const T& src ) const { return GetRef() <= src; }
T operator+( const T& src ) const { return GetRef() + src; }
T operator-( const T& src ) const { return GetRef() - src; }
void operator+=( const T& src ) { GetRef() += src; }
void operator-=( const T& src ) { GetRef() -= src; }
operator T&() const { return GetRef(); }
protected:
void CreateKey();
};
};
template< typename T >
Threading::TlsVariable<T>::TlsVariable()
{
CreateKey();
}
template< typename T >
Threading::TlsVariable<T>::TlsVariable( T initval )
{
CreateKey();
m_initval = initval;
}
template< typename T >
Threading::TlsVariable<T>::~TlsVariable() throw()
{
if( m_thread_key != NULL )
pthread_key_delete( m_thread_key );
}
template< typename T >
T* Threading::TlsVariable<T>::GetPtr() const
{
T* result = (T*)pthread_getspecific( m_thread_key );
if( result == NULL )
{
pthread_setspecific( m_thread_key, result = (T*)_aligned_malloc( sizeof(T), 16 ) );
if( result == NULL )
throw Exception::OutOfMemory( L"Out of memory allocating thread local storage variable." );
*result = m_initval;
}
return result;
}
template< typename T >
void Threading::TlsVariable<T>::CreateKey()
{
if( 0 != pthread_key_create(&m_thread_key, _aligned_free) )
{
pxFailRel( "Thread Local Storage Error: key creation failed." );
}
}