pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor Struct Reference

Cursor over one transform. More...

#include <zero_latency_convolver_support.hpp>

Public Types
enum class	Phase {   idle , gather , butterflies , conjugate ,   permute , scale }

Public Member Functions
bool	done () const
void	begin_forward_from_ring (const SampleType *ring, std::size_t base, std::size_t mask)
	Forward transform of ring[(base + i) & mask], i in [0, size).
void	begin_forward_in_place ()
	Forward transform of the already gathered natural-order data in data, using the in-place permutation and butterfly phases.
void	begin_inverse_in_place ()
	Inverse transform of whatever already sits in data, computed as conj(fft(conj(x)))/N.
void	cancel ()
long	advance (const SlicedFftPlanT &plan, std::complex< SampleType > *data, long budget)

Public Attributes
Phase	phase = Phase::idle
int	cursor = 0
int	stage = 1
bool	inverse = false
const SampleType *	gather_src = nullptr
std::size_t	gather_base = 0
std::size_t	gather_mask = 0

Detailed Description

template<typename SampleType>
struct pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor

Cursor over one transform.

begin_*() arms it; advance() performs work until the budget is spent or the transform completes.

The gather phase reads the source through a power-of-two ring (gather_src / gather_base / gather_mask) rather than from data, which is what lets the convolver's input history keep advancing while a transform over an older frame is still in flight — no snapshot copy is needed, and therefore no unsliceable O(K) memcpy lands in the block where the frame closes.

Member Enumeration Documentation

Phase

template<typename SampleType>

enum class pulp::signal::detail::SlicedFftPlanT::Cursor::Phase

strong

Enumerator
idle
gather
butterflies
conjugate
permute
scale

Member Function Documentation

advance()

template<typename SampleType>

long pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::advance ( const SlicedFftPlanT & plan, std::complex< SampleType > * data, long budget )

inline

begin_forward_from_ring()

template<typename SampleType>

void pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::begin_forward_from_ring ( const SampleType * ring, std::size_t base, std::size_t mask )

inline

Forward transform of ring[(base + i) & mask], i in [0, size).

begin_forward_in_place()

template<typename SampleType>

void pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::begin_forward_in_place ( )

inline

Forward transform of the already gathered natural-order data in data, using the in-place permutation and butterfly phases.

begin_inverse_in_place()

template<typename SampleType>

void pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::begin_inverse_in_place ( )

inline

Inverse transform of whatever already sits in data, computed as conj(fft(conj(x)))/N.

cancel()

template<typename SampleType>

void pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::cancel ( )

inline

done()

template<typename SampleType>

bool pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::done ( ) const

inline

Member Data Documentation

cursor

template<typename SampleType>

int pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::cursor = 0

gather_base

template<typename SampleType>

std::size_t pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::gather_base = 0

gather_mask

template<typename SampleType>

std::size_t pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::gather_mask = 0

gather_src

template<typename SampleType>

const SampleType* pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::gather_src = nullptr

inverse

template<typename SampleType>

bool pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::inverse = false

phase

template<typename SampleType>

Phase pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::phase = Phase::idle

stage

template<typename SampleType>

int pulp::signal::detail::SlicedFftPlanT< SampleType >::Cursor::stage = 1

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

• /home/runner/work/pulp/pulp/core/signal/include/pulp/signal/zero_latency_convolver_support.hpp