Pack 32-bit integers into 512-bit SIMD words using elias gamma with vbyte for short lists. More...

#include <compress_integer_elias_gamma_simd_vb.h>

Inheritance diagram for JASS::compress_integer_elias_gamma_simd_vb:

Collaboration diagram for JASS::compress_integer_elias_gamma_simd_vb:

Public Member Functions
virtual size_t	encode (void encoded, size_t encoded_buffer_length, const integer source, size_t source_integers)
	Encode a sequence of integers returning the number of bytes used for the encoding, or 0 if the encoded sequence doesn't fit in the buffer. More...

virtual void	decode (integer decoded, size_t integers_to_decode, const void source, size_t source_length)
	Decode a sequence of integers encoded with this codex. More...

Public Member Functions inherited from JASS::compress_integer_variable_byte
	compress_integer_variable_byte ()
	Constructor.

virtual	~compress_integer_variable_byte ()
	Constructor.

Public Member Functions inherited from JASS::compress_integer
	compress_integer ()
	Constructor.

virtual	~compress_integer ()
	Destructor.

Static Public Member Functions
static void	unittest (void)
	Unit test this class.

Static Public Member Functions inherited from JASS::compress_integer_variable_byte
static void	static_decode (integer decoded, size_t integers_to_decode, const void source_as_void, size_t source_length)
	Decode a sequence of integers encoded with this codex. More...

static size_t	bytes_needed_for (uint32_t value)
	Return the number of bytes necessary to encode the integer value. More...

static size_t	bytes_needed_for (uint64_t value)
	Return the number of bytes necessary to encode the integer value. More...

template<typename DESTINATION >
static forceinline void	compress_into (DESTINATION &destination, uint32_t value)
	Encode the given integer placing the encoding into destination (whose size is not validated). More...

template<typename DESTINATION >
static forceinline void	compress_into (DESTINATION &destination, uint64_t value)
	Encode the given integer placing the encoding into destination (whose size is not validated). More...

template<typename SOURCE >
static forceinline void	decompress_into (uint16_t *decoded, SOURCE &source)
	Decode the given integer placing the encoding into destination (whose size is not validated). More...

template<typename SOURCE >
static forceinline void	decompress_into (uint32_t *decoded, SOURCE &source)
	Decode the given integer placing the encoding into destination (whose size is not validated). More...

template<typename SOURCE >
static forceinline void	decompress_into (uint64_t *decoded, SOURCE &source)
	Decode the given integer placing the encoding into destination (whose size is not validated). More...

static void	unittest (void)
	Unit test this class.

Static Public Member Functions inherited from JASS::compress_integer
static size_t	d1_encode (integer encoded, const integer source, size_t source_integers)
	Convert an array of integers into an array of D1 (delta, d-gap) encoded integers. More...

static size_t	d1_decode (integer decoded, const integer source, size_t source_integers)
	Convert a D1 encoded array of integers into an array of integers. More...

static size_t	dn_encode (integer encoded, const integer source, size_t source_integers, size_t n=1)
	Convert an array of integers into an array of Dn (delta, d-gap) encoded integers with a gap of n. More...

static size_t	dn_decode (integer decoded, const integer source, size_t source_integers, size_t n=1)
	Convert a Dn encoded array of integers into an array of integers. More...

static void	unittest_one (compress_integer &encoder, const std::vector< uint32_t > &sequence)
	Test one sequence to make sure it encodes and decodes to the same thing. Assert if not. More...

static void	unittest (compress_integer &compressor, uint32_t staring_from=0)
	Unit test this class, assert on failure. More...

Static Protected Member Functions
static uint32_t	compute_selector (const uint8_t *encodings)
	Computer the selector to use for this encoding. More...

static forceinline uint64_t	find_first_set_bit (uint64_t value)
	return the position of the least significant set bit (using a single machine code instruction) More...

Static Protected Attributes
static const uint32_t	mask_set [33][16]

Additional Inherited Members
Public Types inherited from JASS::compress_integer
typedef uint32_t	integer
	This class and descendants will work on integers of this size. Do not change without also changing JASS_COMPRESS_INTEGER_BITS_PER_INTEGER.

Detailed Description

Pack 32-bit integers into 512-bit SIMD words using elias gamma with vbyte for short lists.

see: A. Trotman, K. Lilly (2018), Elias Revisited: Group Elias SIMD Coding, Proceedings of The 23rd Australasian Document Computing Symposium (ADCS 2018)

Member Function Documentation

◆ compute_selector()

uint32_t compress_integer_elias_gamma_simd_vb::compute_selector ( const uint8_t * encodings )

staticprotected

Computer the selector to use for this encoding.

Parameters

encodings [in] The width (in bits) of the (at most) 32 integers. The first integer is at encodngs[0]. leading 0s are used to mark fewer than 32 integers.

Returns: The selector encoded as an integer

◆ decode()

void compress_integer_elias_gamma_simd_vb::decode	(	integer *	decoded,
		size_t	integers_to_decode,
		const void *	source,
		size_t	source_length
	)

virtual

Decode a sequence of integers encoded with this codex.

Parameters

decoded	[out] The sequence of decoded integers.
integers_to_decode	[in] The minimum number of integers to decode (it may decode more).
source	[in] The encoded integers.
source_length	[in] The length (in bytes) of the source buffer.

Reimplemented from JASS::compress_integer_variable_byte.

◆ encode()

size_t compress_integer_elias_gamma_simd_vb::encode	(	void *	encoded,
		size_t	encoded_buffer_length,
		const integer *	source,
		size_t	source_integers
	)

virtual

Encode a sequence of integers returning the number of bytes used for the encoding, or 0 if the encoded sequence doesn't fit in the buffer.

Parameters

encoded	[out] The sequence of bytes that is the encoded sequence.
encoded_buffer_length	[in] The length (in bytes) of the output buffer, encoded.
source	[in] The sequence of integers to encode.
source_integers	[in] The length (in integers) of the source buffer.

Returns: The number of bytes used to encode the integer sequence, or 0 on error (i.e. overflow).

Reimplemented from JASS::compress_integer_variable_byte.

◆ find_first_set_bit()

static forceinline uint64_t JASS::compress_integer_elias_gamma_simd_vb::find_first_set_bit ( uint64_t value )

inlinestaticprotected

return the position of the least significant set bit (using a single machine code instruction)

Parameters

[in] value the integer to check.

Returns: The position of the lowest set bit (or 0 if no bits are set)

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

source/compress_integer_elias_gamma_simd_vb.h
source/compress_integer_elias_gamma_simd_vb.cpp

Public Member Functions

Static Public Member Functions

Static Protected Member Functions

Static Protected Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ compute_selector()

◆ decode()

◆ encode()

◆ find_first_set_bit()