mage::MemoryArena::Allocator< T > Class Template Reference

#include <memory_arena.hpp>

Public Types
using	value_type = T
using	size_type = std::size_t
using	difference_type = std::ptrdiff_t
using	propagate_on_container_move_assignment = std::true_type
using	is_always_equal = std::false_type

Public Member Functions
	Allocator (const Allocator &allocator) noexcept=default
	Allocator (Allocator &&allocator) noexcept=default
template<typename U >
	Allocator (const Allocator< U > &allocator) noexcept
	~Allocator ()=default
Allocator &	operator= (const Allocator &allocator)=delete
Allocator &	operator= (Allocator &&allocator) noexcept=default
T *	allocate (std::size_t count)
T *	allocate (std::size_t count, [[maybe_unused]] const void *hint)
void	deallocate ([[maybe_unused]] T *data, [[maybe_unused]] std::size_t count) const noexcept
template<typename U >
bool	operator== (const Allocator< U > &rhs) const noexcept
template<typename U >
bool	operator!= (const Allocator< U > &rhs) const noexcept

Private Member Functions
	Allocator (NotNull< MemoryArena * > memory_arena) noexcept

Private Attributes
NotNull< MemoryArena *>	m_memory_arena

Friends
class	MemoryArena

Detailed Description

template<typename T>
class mage::MemoryArena::Allocator< T >

A class of allocators for memory arenas.

Template Parameters

T	The data type.

Member Typedef Documentation

difference_type

template<typename T >

using mage::MemoryArena::Allocator< T >::difference_type = std::ptrdiff_t

is_always_equal

template<typename T >

using mage::MemoryArena::Allocator< T >::is_always_equal = std::false_type

propagate_on_container_move_assignment

template<typename T >

using mage::MemoryArena::Allocator< T >::propagate_on_container_move_assignment = std::true_type

size_type

template<typename T >

using mage::MemoryArena::Allocator< T >::size_type = std::size_t

value_type

template<typename T >

using mage::MemoryArena::Allocator< T >::value_type = T

Constructor & Destructor Documentation

Allocator() [1/4]

template<typename T >

mage::MemoryArena::Allocator< T >::Allocator ( const Allocator< T > &  allocator )

defaultnoexcept

Constructs an allocator from the given allocator.

Parameters

[in]

allocator

A reference to the allocator to copy.

Allocator() [2/4]

template<typename T >

mage::MemoryArena::Allocator< T >::Allocator ( Allocator< T > &&  allocator )

defaultnoexcept

Constructs an allocator by moving the given allocator.

Parameters

[in]

allocator

A reference to the allocator to move.

Allocator() [3/4]

template<typename T >

template<typename U >

mage::MemoryArena::Allocator< T >::Allocator ( const Allocator< U > &  allocator )

noexcept

Constructs an allocator from the given allocator.

Template Parameters

U	The data type.

Parameters

[in]

allocator

A reference to the allocator to copy.

~Allocator()

template<typename T >

mage::MemoryArena::Allocator< T >::~Allocator ( )

default

Destructs this allocator.

Allocator() [4/4]

template<typename T >

mage::MemoryArena::Allocator< T >::Allocator ( NotNull< MemoryArena * >  memory_arena )

explicitprivatenoexcept

Constructs an allocator.

Parameters

[in]

memory_arena

A pointer to the memory arena.

Member Function Documentation

allocate() [1/2]

template<typename T >

T* mage::MemoryArena::Allocator< T >::allocate

(

std::size_t

count

)

Allocates a block of storage with a size large enough to contain count elements of type T, and returns a pointer to the first element.

Parameters

[in]

count

The number of objects of type T to allocate in memory.

Returns

A pointer to the memory block that was allocated. The pointer is a multiple of the alignment.

Exceptions

std::bad_alloc

Failed to allocate the memory block.

allocate() [2/2]

template<typename T >

T* mage::MemoryArena::Allocator< T >::allocate	(	std::size_t	count,
		[[maybe_unused] ] const void *	hint
	)

Allocates a block of storage with a size large enough to contain count elements of type T, and returns a pointer to the first element.

Parameters

[in]	count	The number of objects of type T to allocate in memory.
[in]	hint	Either nullptr or a value previously obtained by another call to mage::MemoryArena::Allocator<T>::allocate(std::size_t) and not yet freed with mage::MemoryArena::Allocator<T>::deallocate(T*, std::size_t). When not equal to nullptr, this value may be used as a hint to improve performance by allocating the new block near the one specified. The address of an adjacent element is often a good choice.

Returns

A pointer to the memory block that was allocated. The pointer is a multiple of the alignment.

Exceptions

std::bad_alloc

Failed to allocate the memory block.

deallocate()

template<typename T >

void mage::MemoryArena::Allocator< T >::deallocate ( [[maybe_unused] ] T *  data, [[maybe_unused] ] std::size_t  count  ) const

noexcept

Releases a block of storage previously allocated with mage::MemoryArena::Allocator<T>::allocate(std::size_t) and not yet released.

Parameters

[in]	data	A pointer to the memory block that needs to be released.
[in]	count	The number of objects of type T allocated on the call to allocate this block of storage.

Note

The elements in the array are not destroyed.

operator!=()

template<typename T >

template<typename U >

bool mage::MemoryArena::Allocator< T >::operator!= ( const Allocator< U > &  rhs ) const

noexcept

Compares this allocator to the given allocator for non-equality.

Template Parameters

U	The data type.

Parameters

[in]

rhs

A reference to the allocator to compare with.

Returns

true if and only if storage allocated from this allocator cannot be deallocated from the given allocator, and vice versa. false otherwise.

operator=() [1/2]

template<typename T >

Allocator& mage::MemoryArena::Allocator< T >::operator= ( const Allocator< T > &  allocator )

delete

Copies the given allocator to this allocator.

Parameters

[in]

allocator

A reference to the allocator to copy.

Returns

A reference to the copy of the given allocator (i.e. this allocator).

operator=() [2/2]

template<typename T >

Allocator& mage::MemoryArena::Allocator< T >::operator= ( Allocator< T > &&  allocator )

defaultnoexcept

Moves the given allocator to this allocator.

Parameters

[in]

allocator

A reference to the allocator to move.

Returns

A reference to the moved allocator (i.e. this allocator).

operator==()

template<typename T >

template<typename U >

bool mage::MemoryArena::Allocator< T >::operator== ( const Allocator< U > &  rhs ) const

noexcept

Compares this allocator to the given allocator for equality.

Template Parameters

U	The data type.

Parameters

[in]

rhs

A reference to the allocator to compare with.

Returns

true if and only if storage allocated from this allocator can be deallocated from the given allocator, and vice versa. false otherwise.

Friends And Related Function Documentation

MemoryArena

template<typename T >

friend class MemoryArena

friend

Member Data Documentation

m_memory_arena

template<typename T >

NotNull< MemoryArena* > mage::MemoryArena::Allocator< T >::m_memory_arena

private

A pointer to the memory arena of this allocator.