bb::stdlib::straus_scalar_slices< Builder > Class Template Reference

straus_scalar_slices decomposes an input scalar into bit-slices of size table_bits. Used in batch_mul, which implements the Straus multiscalar multiplication algorithm. More...

#include <straus_scalar_slice.hpp>

Public Types
using	field_t = stdlib::field_t< Builder >

Public Member Functions
	straus_scalar_slices (Builder *context, const cycle_scalar< Builder > &scalars, size_t table_bits)
	Construct straus_scalar_slices from an input cycle_scalar and specified table_bits.
field_t	operator[] (size_t index)
	Return a bit-slice associated with round index.

Public Attributes
size_t	_table_bits
std::vector< field_t >	slices
std::vector< uint64_t >	slices_native

Static Private Member Functions
static std::pair< std::vector< field_t >, std::vector< uint64_t > >	compute_scalar_slices (Builder *context, const field_t &scalar, size_t num_bits, size_t table_bits)
	Convert an input cycle_scalar field element into a vector of bit-slices.

Detailed Description

template<typename Builder>
class bb::stdlib::straus_scalar_slices< Builder >

straus_scalar_slices decomposes an input scalar into bit-slices of size table_bits. Used in batch_mul, which implements the Straus multiscalar multiplication algorithm.

Definition at line 24 of file straus_scalar_slice.hpp.

Member Typedef Documentation

field_t

template<typename Builder >

using bb::stdlib::straus_scalar_slices< Builder >::field_t = stdlib::field_t<Builder>

Definition at line 26 of file straus_scalar_slice.hpp.

Constructor & Destructor Documentation

straus_scalar_slices()

template<typename Builder >

bb::stdlib::straus_scalar_slices< Builder >::straus_scalar_slices	(	Builder *	context,
		const cycle_scalar< Builder > &	scalar,
		size_t	table_bits
	)

Construct straus_scalar_slices from an input cycle_scalar and specified table_bits.

Performs an in-circuit decomposition of the input cycle_scalar into bit-slices of size table_bits.

Template Parameters

Builder

Parameters

context
scalar
table_bits

Definition at line 82 of file straus_scalar_slice.cpp.

Member Function Documentation

compute_scalar_slices()

template<typename Builder >

std::pair< std::vector< field_t< Builder > >, std::vector< uint64_t > > bb::stdlib::straus_scalar_slices< Builder >::compute_scalar_slices ( Builder *  context, const field_t &  scalar, size_t  num_bits, size_t  table_bits  )

staticprivate

Convert an input cycle_scalar field element into a vector of bit-slices.

Each slice contains table_bits bits. Also performs an implicit range check on the input slices via decompose_into_default_range

Template Parameters

Builder

Parameters

context	The circuit builder
scalar	The field element to decompose
num_bits	Number of bits in the scalar
table_bits	Number of bits per slice

Returns

pair of stdlib slices and native slices

Definition at line 28 of file straus_scalar_slice.cpp.

operator[]()

template<typename Builder >

field_t< Builder > bb::stdlib::straus_scalar_slices< Builder >::operator[]

(

size_t

index

)

Return a bit-slice associated with round index.

In Straus algorithm, index is a known parameter, so no need for expensive lookup tables

Template Parameters

Builder

Parameters

index

Returns

field_t<Builder>

Definition at line 114 of file straus_scalar_slice.cpp.

Member Data Documentation

_table_bits

template<typename Builder >

size_t bb::stdlib::straus_scalar_slices< Builder >::_table_bits

Definition at line 30 of file straus_scalar_slice.hpp.

slices

template<typename Builder >

std::vector<field_t> bb::stdlib::straus_scalar_slices< Builder >::slices

Definition at line 31 of file straus_scalar_slice.hpp.

slices_native

template<typename Builder >

std::vector<uint64_t> bb::stdlib::straus_scalar_slices< Builder >::slices_native

Definition at line 32 of file straus_scalar_slice.hpp.

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

• src/barretenberg/stdlib/primitives/group/straus_scalar_slice.hpp
• src/barretenberg/stdlib/primitives/group/straus_scalar_slice.cpp