Struct curve25519_dalek::backend::vector::avx2::edwards::CachedPoint

pub struct CachedPoint(pub(super) FieldElement2625x4);

This is supported on feature="simd_backend" and (target feature avx2 or target feature avx512ifma) and target feature avx2 and non-target feature avx512ifma only.

A cached point with some precomputed variables used for readdition.

Warning

It is not safe to negate this point more than once.

Invariant

As long as the CachedPoint is not repeatedly negated, its coefficients will be bounded with \( b < 1.0 \).

Trait Implementations

impl Identity for CachedPoint

fn identity() -> CachedPoint

Returns the identity element of the curve. Can be used as a constructor.

impl Clone for CachedPoint

fn clone(&self) -> CachedPoint

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CachedPoint

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl From<ExtendedPoint> for CachedPoint

fn from(P: ExtendedPoint) -> CachedPoint

Performs the conversion.

impl Copy for CachedPoint

impl<'a, 'b> Add<&'b CachedPoint> for &'a ExtendedPoint

type Output = ExtendedPoint

The resulting type after applying the + operator.

fn add(self, other: &'b CachedPoint) -> ExtendedPoint

Add an ExtendedPoint and a CachedPoint.

impl<'a, 'b> Sub<&'b CachedPoint> for &'a ExtendedPoint

type Output = ExtendedPoint

The resulting type after applying the - operator.

fn sub(self, other: &'b CachedPoint) -> ExtendedPoint

Implement subtraction by negating the point and adding.

Empirically, this seems about the same cost as a custom subtraction impl (maybe because the benefit is cancelled by increased code size?)

impl<'a> Neg for &'a CachedPoint

type Output = CachedPoint

The resulting type after applying the - operator.

fn neg(self) -> CachedPoint

Lazily negate the point.

Warning

Because this method does not perform a reduction, it is not safe to repeatedly negate a point.

impl Default for CachedPoint

fn default() -> CachedPoint

Returns the "default value" for a type.

impl ConditionallySelectable for CachedPoint

fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self

Select a or b according to choice.

fn conditional_assign(&mut self, other: &Self, choice: Choice)

Conditionally assign other to self, according to choice.

fn conditional_swap(a: &mut Self, b: &mut Self, choice: Choice)

Conditionally swap self and other if choice == 1; otherwise, reassign both unto themselves.