#include <gromacs/utility/alignedallocator.h>

Description

template<class T>
class gmx::AlignedAllocator< T >

Aligned memory allocator.

Template Parameters

T	Type of objects to allocate

This class can be used for the optional allocator template parameter in standard library containers, which is necessary e.g. to use SIMD aligned load and store operations in those containers. The memory will always be aligned to 128 bytes, which is our estimate of the longest cache lines on architectures currently in use. It will also be padded by the same amount at the end of the area, to help avoid false cache sharing.

Exceptions

std::bad_alloc Instead of a GROMACS exception object we throw the standard one on allocation failures to make it as compatible as possible with the errors expected by code using the standard library containers.

Classes
struct	rebind
	Standard-required typedef to use allocator with different class. More...

Public Types
typedef T	value_type
	Type of allocated elements.

typedef T &	reference
	Reference to allocated elements.

typedef const T &	const_reference
	Constant reference to allocated elements.

typedef T *	pointer
	Pointer to allocated elements.

typedef const T *	const_pointer
	Constant pointer to allocated elements.

typedef std::size_t	size_type
	Integer type to use for size of objects.

typedef std::ptrdiff_t	difference_type
	Type to hold differences between pointers.

Public Member Functions
template<class U >
	AlignedAllocator (const AlignedAllocator< U > &)
	Templated copy constructor. More...

	AlignedAllocator ()
	Constructor. More...

pointer	address (reference r) const
	Return address of an object. More...

const_pointer	address (const_reference r) const
	Return address of a const object. More...

pointer	allocate (std::size_t n, typename std::allocator< void >::const_pointer hint=0)
	Do the actual memory allocation. More...

void	deallocate (pointer p, std::size_t n)
	Release memory. More...

template<class... Args>
void	construct (pointer p, Args &&...args)
	Construct an object without allocating memory. More...

void	destroy (pointer p)
	Call the destructor of object without releasing memory. More...

std::size_t	max_size () const
	Return largest number of objects that can be allocated. More...

template<class T2 >
bool	operator== (const AlignedAllocator< T2 > &rhs) const
	Return true if two allocators are identical. More...

bool	operator!= (const AlignedAllocator &rhs) const
	Return true if two allocators are different. More...

Constructor & Destructor Documentation

template<class T >

template<class U >

gmx::AlignedAllocator< T >::AlignedAllocator ( const AlignedAllocator< U > & )

inlineexplicit

Templated copy constructor.

This template constructor cannot be auto-generated, and is normally unused, except e.g. MSVC2015 standard library uses it in debug mode, presumably to implement some checks.

template<class T >

gmx::AlignedAllocator< T >::AlignedAllocator ( )

inline

Constructor.

No constructor can be auto-generated in the presence of any user-defined constructor, but we want the default constructor.

Member Function Documentation

template<class T >

pointer gmx::AlignedAllocator< T >::address ( reference r ) const

inline

Return address of an object.

Parameters

r	Reference to object of type T

Returns: Pointer to T memory

template<class T >

const_pointer gmx::AlignedAllocator< T >::address ( const_reference r ) const

inline

Return address of a const object.

Parameters

r	Const reference to object of type T

Returns: Pointer to T memory

template<class T >

pointer gmx::AlignedAllocator< T >::allocate	(	std::size_t	n,
		typename std::allocator< void >::const_pointer	hint = `0`
	)

inline

Do the actual memory allocation.

Parameters

n	Number of elements of type T to allocate. n can be 0 bytes, which will return a non-null properly aligned and padded pointer that should not be used.
hint	Optional value returned from previous call to allocate. For now this is not used.

Returns: Pointer to allocated memory

Exceptions

std::bad_alloc if the allocation fails.

template<class T >

template<class... Args>

void gmx::AlignedAllocator< T >::construct	(	pointer	p,
		Args &&...	args
	)

inline

Construct an object without allocating memory.

Template Parameters

Args	Variable-length list of types for constructor args

Parameters

p	Adress of memory where to construct object
args	Variable-length list of arguments to constructor

template<class T >

void gmx::AlignedAllocator< T >::deallocate	(	pointer	p,
		std::size_t	n
	)

inline

Release memory.

Parameters

p	Pointer to previously allocated memory returned from allocate()
n	number of objects previously passed to allocate()

template<class T >

void gmx::AlignedAllocator< T >::destroy ( pointer p )

inline

Call the destructor of object without releasing memory.

Parameters

p	Address of memory where to destroy object

template<class T >

std::size_t gmx::AlignedAllocator< T >::max_size ( ) const

inline

Return largest number of objects that can be allocated.

This will be set such that the number of objects T multiplied by the size of each object is the largest value that can be represented by size_type.

template<class T >

bool gmx::AlignedAllocator< T >::operator!= ( const AlignedAllocator< T > & rhs ) const

inline

Return true if two allocators are different.

Parameters

rhs	Other allocator.

This is a member function of the left-hand-side allocator.

template<class T >

template<class T2 >

bool gmx::AlignedAllocator< T >::operator== ( const AlignedAllocator< T2 > & rhs ) const

inline

Return true if two allocators are identical.

Parameters

rhs	Other allocator

This is a member function of the left-hand-side allocator.

The documentation for this class was generated from the following file:

src/gromacs/utility/alignedallocator.h

Description

template<class T> class gmx::AlignedAllocator< T >

Classes

Public Types

Public Member Functions

Constructor & Destructor Documentation

Member Function Documentation

template<class T>
class gmx::AlignedAllocator< T >