Tools related to raw memory manipulation. More...

Typedefs
using	cpp::detail::AlignedMallocAlingOffset = std::uint8_t
	Type used to store the offset between the aligned pointer returned by aligned_malloc() and the beginning of the allocated block. More...

Functions
SIPLASPLAS_UTILITY_EXPORT char *	cpp::detail::aligned_ptr (char *pointer, std::size_t alignment)
	Returns an address aligned to an specific boundary. More...

SIPLASPLAS_UTILITY_EXPORT void *	cpp::detail::aligned_ptr (void *pointer, std::size_t alignment)
	Returns an address aligned to an specific boundary. More...

SIPLASPLAS_UTILITY_EXPORT const char *	cpp::detail::aligned_ptr (const char *pointer, std::size_t alignment)
	Returns an address aligned to an specific boundary. More...

SIPLASPLAS_UTILITY_EXPORT const void *	cpp::detail::aligned_ptr (const void *pointer, std::size_t alignment)
	Returns an address aligned to an specific boundary. More...

SIPLASPLAS_UTILITY_EXPORT bool	cpp::detail::is_aligned (char *pointer, std::size_t alignment)
	Checks if an address is aligned to a given boundary. More...

SIPLASPLAS_UTILITY_EXPORT bool	cpp::detail::is_aligned (void *pointer, std::size_t alignment)
	Checks if an address is aligned to a given boundary. More...

SIPLASPLAS_UTILITY_EXPORT bool	cpp::detail::is_aligned (const char *pointer, std::size_t alignment)
	Checks if an address is aligned to a given boundary. More...

SIPLASPLAS_UTILITY_EXPORT bool	cpp::detail::is_aligned (const void *pointer, std::size_t alignment)
	Checks if an address is aligned to a given boundary. More...

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t	cpp::detail::missalignment (const char *address, std::size_t alignment)
	Returns the distance between a memory address and the next address aligned to the given boundary. More...

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t	cpp::detail::missalignment (const void *address, std::size_t alignment)
	Returns the distance between a memory address and the next address aligned to the given boundary. More...

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t	cpp::detail::missalignment (char *address, std::size_t alignment)
	Returns the distance between a memory address and the next address aligned to the given boundary. More...

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t	cpp::detail::missalignment (void *address, std::size_t alignment)
	Returns the distance between a memory address and the next address aligned to the given boundary. More...

template<typename T , typename U >
T *	cpp::detail::tagPointer (T *pointer, U data)
	Tags a pointer with the specified data. More...

template<typename R , typename U , typename... Args>
auto	cpp::detail::tagPointer (R(*pointer)(Args...), U data) -> decltype(pointer)
	Tags a pointer with the specified data. More...

template<typename T >
T *	cpp::detail::untagPointer (T *pointer)
	Untags a pointer. More...

template<typename R , typename... Args>
auto	cpp::detail::untagPointer (R(*pointer)(Args...)) -> decltype(pointer)
	Untags a pointer. More...

template<typename T >
std::uint16_t	cpp::detail::readTaggedPointer (T *pointer)
	Reads the data stored in a tagged pointer. More...

template<typename R , typename... Args>
std::uint16_t	cpp::detail::readTaggedPointer (R(*pointer)(Args...))
	Reads the data stored in a tagged pointer. More...

SIPLASPLAS_UTILITY_EXPORT void *	cpp::detail::aligned_malloc (std::size_t size, std::size_t alignment, std::size_t offset=0)
	Allocates a block of memory of memory aligned to an specific boundary. More...

SIPLASPLAS_UTILITY_EXPORT void *	cpp::detail::aligned_malloc_block (void *pointer, std::size_t offset=0)
	Returns a pointer to the full block allocated by cpp::aligned_malloc() More...

SIPLASPLAS_UTILITY_EXPORT void	cpp::detail::aligned_free (void *pointer, std::size_t offset=0)
	Deallocates a block allocated by cpp::aligned_malloc() More...

Detailed Description

Tools related to raw memory manipulation.

Typedef Documentation

using cpp::detail::AlignedMallocAlingOffset = typedef std::uint8_t

Type used to store the offset between the aligned pointer returned by aligned_malloc() and the beginning of the allocated block.

This type limits the maximum alignment requirement that can be passed to aligned_malloc() stores the distance to the start of the allocated block so it can be deallocated in aligned_free(). To use as little extra memory as possible, a 8 bit unsigned integer is used by default, which means up to 256 byte alignment boundary is supported by default. Users can change that limit by defining SIPLASPLAS_UTILITY_ALIGNEDMALLOC_ALIGNOFFSET_BITS to the with in bits of the unsigned integer used for offset storage (8, 16, 32, and 64 are supported)

#define SIPLASPLAS_UTILITY_ALIGNEDMALLOC_ALIGNEDOFFSET_BITS 32
#include <siplasplas/utility/memory_manip.hpp>
void* ptr =cpp::aligned_malloc(1024, 1024); // Allocate 1024 bytes in the 1024 boundary

Function Documentation

SIPLASPLAS_UTILITY_EXPORT void cpp::detail::aligned_free	(	void *	pointer,
		std::size_t	offset = `0`
	)

Deallocates a block allocated by cpp::aligned_malloc()

Parameters

pointer	Pointer to the allocated block
offset	User offset. The behavior is undefined if it's different to the argument given to cpp::aligned_malloc() when allocating the block

SIPLASPLAS_UTILITY_EXPORT void* cpp::detail::aligned_malloc	(	std::size_t	size,
		std::size_t	alignment,
		std::size_t	offset = `0`
	)

Allocates a block of memory of memory aligned to an specific boundary.

This function allocates a memory block starting at a specific alignment boundary. Users can also set some extra bytes for bookeeping data before the returned block. To deallocate blocks allocated with aligned_malloc(), use aligned_free(), never std::free()

Parameters

size	Requested block size in bytes
alignment	Required alignment boundary. Must be a power of two
offset	Extra space reserved for the user right brefore the returned block. 0 by default.

Returns: A pointer to a memory block of size bytes, multiple of alignment. nullptr if fails

SIPLASPLAS_UTILITY_EXPORT void* cpp::detail::aligned_malloc_block	(	void *	pointer,
		std::size_t	offset = `0`
	)

Returns a pointer to the full block allocated by cpp::aligned_malloc()

aligned_malloc() allocates an oversized block in order to acomplish the alignment requirements While aligned_malloc() returns the expected aligned block, this function can be used to get the complete allocated block.

Parameters

pointer	Pointer to a block allocated by cpp::aligned_malloc()
offset	User offset. The behavior is undefined if it's different to the argument given to cpp::aligned_malloc() when allocating the block

Returns: A pointer to the beginning of the complete allocated block. This pointer can be deallocated by std::free().

SIPLASPLAS_UTILITY_EXPORT char* cpp::detail::aligned_ptr	(	char *	pointer,
		std::size_t	alignment
	)

Returns an address aligned to an specific boundary.

Parameters

pointer	Starting address
alignment	Alignment boundary. Must be a power of two

Returns: The next (upper) address from the given address that's aligned to the required boundary

SIPLASPLAS_UTILITY_EXPORT void* cpp::detail::aligned_ptr	(	void *	pointer,
		std::size_t	alignment
	)

Returns an address aligned to an specific boundary.

Parameters

pointer	Starting address
alignment	Alignment boundary. Must be a power of two

Returns: The next (upper) address from the given address that's aligned to the required boundary

SIPLASPLAS_UTILITY_EXPORT const char* cpp::detail::aligned_ptr	(	const char *	pointer,
		std::size_t	alignment
	)

Returns an address aligned to an specific boundary.

Parameters

pointer	Starting address
alignment	Alignment boundary. Must be a power of two

Returns: The next (upper) address from the given address that's aligned to the required boundary

SIPLASPLAS_UTILITY_EXPORT const void* cpp::detail::aligned_ptr	(	const void *	pointer,
		std::size_t	alignment
	)

Returns an address aligned to an specific boundary.

Parameters

pointer	Starting address
alignment	Alignment boundary. Must be a power of two

Returns: The next (upper) address from the given address that's aligned to the required boundary

SIPLASPLAS_UTILITY_EXPORT bool cpp::detail::is_aligned	(	char *	pointer,
		std::size_t	alignment
	)

Checks if an address is aligned to a given boundary.

Parameters

pointer	Address to check
alignment	Required alignment. Must be a power of two

Returns: true if pointer is aligned to alignment boundary. False otherwise.

SIPLASPLAS_UTILITY_EXPORT bool cpp::detail::is_aligned	(	void *	pointer,
		std::size_t	alignment
	)

Checks if an address is aligned to a given boundary.

Parameters

pointer	Address to check
alignment	Required alignment. Must be a power of two

Returns: true if pointer is aligned to alignment boundary. False otherwise.

SIPLASPLAS_UTILITY_EXPORT bool cpp::detail::is_aligned	(	const char *	pointer,
		std::size_t	alignment
	)

Checks if an address is aligned to a given boundary.

Parameters

pointer	Address to check
alignment	Required alignment. Must be a power of two

Returns: true if pointer is aligned to alignment boundary. False otherwise.

SIPLASPLAS_UTILITY_EXPORT bool cpp::detail::is_aligned	(	const void *	pointer,
		std::size_t	alignment
	)

Checks if an address is aligned to a given boundary.

Parameters

pointer	Address to check
alignment	Required alignment. Must be a power of two

Returns: true if pointer is aligned to alignment boundary. False otherwise.

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t cpp::detail::missalignment	(	const char *	address,
		std::size_t	alignment
	)

Returns the distance between a memory address and the next address aligned to the given boundary.

Parameters

address	Memory address
alignment	Required alignment. Must be a power of two

Returns: The distance in bytes to the next aligned address

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t cpp::detail::missalignment	(	const void *	address,
		std::size_t	alignment
	)

Returns the distance between a memory address and the next address aligned to the given boundary.

Parameters

address	Memory address
alignment	Required alignment. Must be a power of two

Returns: The distance in bytes to the next aligned address

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t cpp::detail::missalignment	(	char *	address,
		std::size_t	alignment
	)

Returns the distance between a memory address and the next address aligned to the given boundary.

Parameters

address	Memory address
alignment	Required alignment. Must be a power of two

Returns: The distance in bytes to the next aligned address

SIPLASPLAS_UTILITY_EXPORT std::uintptr_t cpp::detail::missalignment	(	void *	address,
		std::size_t	alignment
	)

Returns the distance between a memory address and the next address aligned to the given boundary.

Parameters

address	Memory address
alignment	Required alignment. Must be a power of two

Returns: The distance in bytes to the next aligned address

template<typename T >

std::uint16_t cpp::detail::readTaggedPointer ( T * pointer )

Reads the data stored in a tagged pointer.

Assuming the pointer is a tagged pointer, this function reads the data tagged in the 16 more significative bits of the pointer. Compilation fails if this function is used in non 64 bit architectures.

Parameters

pointer Tagged pointer to read

Returns: The 16 bit unsigned integer value tagged in the pointer

template<typename R , typename... Args>

std::uint16_t cpp::detail::readTaggedPointer ( R(*)(Args...) pointer )

Reads the data stored in a tagged pointer.

Assuming the pointer is a tagged pointer, this function reads the data tagged in the 16 more significative bits of the pointer. Compilation fails if this function is used in non 64 bit architectures.

Parameters

pointer Tagged pointer to read

Returns: The 16 bit unsigned integer value tagged in the pointer

template<typename T , typename U >

T* cpp::detail::tagPointer	(	T *	pointer,
		U	data
	)

Tags a pointer with the specified data.

This function uses the tagged pointer technique to store data in a 64 bit virtual memory address. Passing data of more than 16 bits wide has undefined behavior. Compilation fails if this function is used in non 64 bit architectures. Note accessing a tagged pointer directly may cause a segmentation fault. See cpp::untagPointer().

Template Parameters

T	Pointed type
U	Must be an integral type of max sizeof(U) = 16 bit

Parameters

pointer	pointer where to store data
data	data to store

Returns: A pointer of type T* with the data and the same address

template<typename R , typename U , typename... Args>

auto cpp::detail::tagPointer	(	R(*)(Args...)	pointer,
		U	data
	)		-> decltype(pointer)

Tags a pointer with the specified data.

This function uses the tagged pointer technique to store data in a 64 bit virtual memory address. Passing data of more than 16 bits wide has undefined behavior. Compilation fails if this function is used in non 64 bit architectures. Note accessing a tagged pointer directly may cause a segmentation fault. See cpp::untagPointer().

Template Parameters

U	Must be an integral type of max sizeof(U) = 16 bit

Parameters

pointer	pointer where to store data
data	data to store

Returns: A pointer of type T* with the data and the same address

template<typename T >

T* cpp::detail::untagPointer ( T * pointer )

Untags a pointer.

Assuming the pointer is a tagged pointer, this function removes the tagged data and returns the memory address ready to be referenced. Compilation fails if this function is used in non 64 bit architectures.

Parameters

pointer Tagged pointer to clear

Returns: The given pointer with the 16 upper bits cleared

template<typename R , typename... Args>

auto cpp::detail::untagPointer ( R(*)(Args...) pointer ) -> decltype(pointer)

Untags a pointer.

Assuming the pointer is a tagged pointer, this function removes the tagged data and returns the memory address ready to be referenced. Compilation fails if this function is used in non 64 bit architectures.

Parameters

pointer Tagged pointer to clear

Returns: The given pointer with the 16 upper bits cleared

Typedefs

Functions

Detailed Description

Typedef Documentation

Function Documentation