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Changed include path to be direct instead of relying upon project settings.

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git-svn-id: svn://svn.code.sf.net/p/loki-lib/code/trunk@271 7ec92016-0320-0410-acc4-a06ded1c099a
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rich_sposato 2005-09-26 21:38:54 +00:00
parent dcb1d09cd5
commit e529d13e1b
3 changed files with 333 additions and 180 deletions
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158
include/loki/SmallObj.h
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@ -41,52 +41,121 @@ namespace Loki
{
class FixedAllocator;
////////////////////////////////////////////////////////////////////////////////
// class SmallObjAllocator
// Manages pool of fixed-size allocators.
////////////////////////////////////////////////////////////////////////////////
/** @class SmallObjAllocator Manages pool of fixed-size allocators.
Designed to be a non-templated base class of AllocatorSingleton so that
implementation details can be safely hidden in the source code file.
*/
class SmallObjAllocator
{
protected:
/** The only available constructor needs certain parameters in order to
initialize all the FixedAllocator's. This throws only if
@param pageSize # of bytes in a page of memory.
@param maxObjectSize Max # of bytes which this may allocate.
@param objectAlignSize # of bytes between alignment boundaries.
*/
SmallObjAllocator( std::size_t pageSize, std::size_t maxObjectSize,
std::size_t objectAlignSize );
/** Destructor releases all blocks, all Chunks, and FixedAllocator's.
Any outstanding blocks are unavailable, and should not be used after
this destructor is called.
*/
~SmallObjAllocator( void );
public:
/** Allocates a block of memory of requested size. Complexity is often
constant-time, but might be O(C) where C is the number of Chunks in a
FixedAllocator.
@par Exception Safety Level
Provides either strong-exception safety, or no-throw exception-safety
level depending upon doThrow parameter. The reason it provides two
levels of exception safety is because it is used by both the nothrow
and throwing new operators. The underlying implementation will never
throw of its own accord, but this can decide to throw if it does not
allocate. The only exception it should emit is std::bad_alloc.
@par Allocation Failure
If it does not allocate, it will call TrimExcessMemory and attempt to
allocate again, before it decides to throw or return NULL. Many
allocators loop through several new_handler functions, and terminate
if they can not allocate, but not this one. It only makes one attempt
using its own implementation of the new_handler, and then returns NULL
or throws so that the program can decide what to do at a higher level.
(Side note: Even though the C++ Standard allows allocators and
new_handlers to terminate if they fail, the Loki allocator does not do
that since that policy is not polite to a host program.)
@param size # of bytes needed for allocation.
@param doThrow True if this should throw if unable to allocate, false
if it should provide no-throw exception safety level.
@return NULL if nothing allocated and doThrow is false. Else the
pointer to an available block of memory.
*/
void * Allocate( std::size_t size, bool doThrow );
/** Deallocates a block of memory at a given place and of a specific
size. Complexity is almost always constant-time, and is O(C) only if
it has to search for which Chunk deallocates. This never throws.
*/
void Deallocate( void * p, std::size_t size );
/** Deallocates a block of memory at a given place but of unknown size
size. Complexity is O(F + C) where F is the count of FixedAllocator's
in the pool, and C is the number of Chunks in all FixedAllocator's. This
does not throw exceptions. This overloaded version of Deallocate is
called by the nothow delete operator - which is called when the nothrow
new operator is used, but a constructor throws an exception.
*/
void Deallocate( void * p );
/// Returns max # of bytes which this can allocate.
inline std::size_t GetMaxObjectSize() const { return maxSmallObjectSize_; }
/// Returns # of bytes between allocation boundaries.
inline std::size_t GetAlignment() const { return objectAlignSize_; }
/** Releases empty Chunks from memory. Complexity is O(F + C) where F
is the count of FixedAllocator's in the pool, and C is the number of
Chunks in all FixedAllocator's. This will never throw. This is called
by AllocatorSingleto::ClearExtraMemory, the new_handler function for
Loki's allocator, and is called internally when an allocation fails.
@return True if any memory released, or false if none released.
*/
bool TrimExcessMemory( void );
private:
/// Default-constructor is not implemented.
SmallObjAllocator( void );
/// Copy-constructor is not implemented.
SmallObjAllocator( const SmallObjAllocator & );
/// Copy-assignment operator is not implemented.
SmallObjAllocator & operator = ( const SmallObjAllocator & );
/// Pointer to array of fixed-size allocators.
Loki::FixedAllocator * pool_;
/// Largest object size supported by allocators.
std::size_t maxSmallObjectSize_;
/// Size of alignment boundaries.
std::size_t objectAlignSize_;
};
////////////////////////////////////////////////////////////////////////////////
// class AllocatorSingleton
// This template class is derived from SmallObjAllocator in order to pass template
// arguments into SmallObjAllocator, and still have a default constructor for the
// singleton.
////////////////////////////////////////////////////////////////////////////////
/** @class AllocatorSingleton This template class is derived from
SmallObjAllocator in order to pass template arguments into it, and still
have a default constructor for the singleton. Each instance is a unique
combination of all the template parameters, and hence is singleton only
with respect to those parameters. The template parameters have default
values and the class has typedefs identical to both SmallObject and
SmallValueObject so that this class can be used directly instead of going
through SmallObject or SmallValueObject. That design feature allows
clients to use the new_handler without having the name of the new_handler
function show up in classes derived from SmallObject or SmallValueObject.
Thus, the only functions in the allocator which show up in SmallObject or
SmallValueObject inheritance heierarchies are the new and delete operators.
*/
template
<
template <class> class ThreadingModel = LOKI_DEFAULT_THREADING_NO_OBJ_LEVEL,
@ -110,16 +179,28 @@ namespace Loki
typedef Loki::SingletonHolder< MyAllocator, Loki::CreateStatic,
LifetimePolicy, ThreadingModel > MyAllocatorSingleton;
/// Returns reference to the singleton.
inline static AllocatorSingleton & Instance( void )
{
return MyAllocatorSingleton::Instance();
}
/// The default constructor is not meant to be called directly.
inline AllocatorSingleton() :
SmallObjAllocator( chunkSize, maxSmallObjectSize, objectAlignSize )
{}
/// The destructor is not meant to be called directly.
inline ~AllocatorSingleton( void ) {}
/** Clears any excess memory used by the allocator. Complexity is
O(F + C) where F is the count of FixedAllocator's in the pool, and C
is the number of Chunks in all FixedAllocator's. This never throws.
@note This function can be used as a new_handler when Loki and other
memory allocators can no longer allocate. Although the C++ Standard
allows new_handler functions to terminate the program when they can
not release any memory, this will not do so.
*/
static void ClearExtraMemory( void );
private:
@ -145,11 +226,12 @@ namespace Loki
}
////////////////////////////////////////////////////////////////////////////////
// class SmallObjectBase
// Base class for small object allocation classes.
////////////////////////////////////////////////////////////////////////////////
/** @class SmallObjectBase Base class for small object allocation classes.
The shared implementation of the new and delete operators are here instead
of being duplicated in both SmallObject or SmallValueObject. This class
is not meant to be used directly by clients, or derived from by clients.
Class has no data members so compilers can use Empty-Base-Optimization.
*/
template
<
template <class> class ThreadingModel,
@ -176,7 +258,7 @@ namespace Loki
public:
/// Throwing single-object new.
/// Throwing single-object new throws bad_alloc when allocation fails.
#ifdef _MSC_VER
/// @note MSVC complains about non-empty exception specification lists.
static void * operator new ( std::size_t size )
@ -189,7 +271,7 @@ namespace Loki
return MyAllocatorSingleton::Instance().Allocate( size, true );
}
/// Non-throwing single-object new.
/// Non-throwing single-object new returns NULL if allocation fails.
static void * operator new ( std::size_t size, const std::nothrow_t & ) throw ()
{
typename MyThreadingModel::Lock lock;
@ -197,7 +279,7 @@ namespace Loki
return MyAllocatorSingleton::Instance().Allocate( size, false );
}
/// Placement single-object new.
/// Placement single-object new merely calls global placement new.
inline static void * operator new ( std::size_t size, void * place )
{
return ::operator new( size, place );
@ -211,7 +293,9 @@ namespace Loki
MyAllocatorSingleton::Instance().Deallocate( p, size );
}
/// Non-throwing single-object delete.
/** Non-throwing single-object delete is only called when nothrow
new operator is used, and the constructor throws an exception.
*/
static void operator delete ( void * p, const std::nothrow_t & ) throw()
{
typename MyThreadingModel::Lock lock;
@ -219,7 +303,7 @@ namespace Loki
MyAllocatorSingleton::Instance().Deallocate( p );
}
/// Placement single-object delete.
/// Placement single-object delete merely calls global placement delete.
inline static void operator delete ( void * p, void * place )
{
::operator delete ( p, place );
@ -235,12 +319,13 @@ namespace Loki
}; // end class SmallObjectBase
////////////////////////////////////////////////////////////////////////////////
// class SmallObject
// Base class for polymorphic small objects, offers fast allocations &
// deallocations. Destructor is virtual and public.
////////////////////////////////////////////////////////////////////////////////
/** @class SmallObject Base class for polymorphic small objects, offers fast
allocations & deallocations. Destructor is virtual and public. Default
constructor is trivial. Copy-constructor and copy-assignment operator are
not implemented since polymorphic classes almost always disable those
operations. Class has no data members so compilers can use
Empty-Base-Optimization.
*/
template
<
template <class> class ThreadingModel = LOKI_DEFAULT_THREADING_NO_OBJ_LEVEL,
@ -266,12 +351,14 @@ namespace Loki
}; // end class SmallObject
////////////////////////////////////////////////////////////////////////////////
// class SmallValueObject
// Base class for small objects with value semantics - offers fast allocations &
// deallocations. Destructor is non-virtual, inline, and protected.
////////////////////////////////////////////////////////////////////////////////
/** @class SmallValueObject Base class for small objects with value-type
semantics - offers fast allocations & deallocations. Destructor is
non-virtual, inline, and protected to prevent unintentional destruction
through base class. Default constructor is trivial. Copy-constructor
and copy-assignment operator are trivial since value-types almost always
need those operations. Class has no data members so compilers can use
Empty-Base-Optimization.
*/
template
<
template <class> class ThreadingModel = LOKI_DEFAULT_THREADING_NO_OBJ_LEVEL,
@ -298,6 +385,9 @@ namespace Loki
// Nov. 26, 2004: re-implemented by Rich Sposato.
//
// $Log$
// Revision 1.10 2005/09/26 21:38:54 rich_sposato
// Changed include path to be direct instead of relying upon project settings.
//
// Revision 1.9 2005/09/26 07:33:04 syntheticpp
// move macros into LOKI_ namespace
//