Struct ByteMatrix 

pub struct ByteMatrix(/* private fields */);

An F_2-linear map on a byte, held the way the affine-byte instruction reads it.

Output bit i is the parity of the input byte against byte 7 - i of the quadword.

    out[i] = XOR over b of row[7 - i][b] * in[b]

Squaring, scaling by a constant, a basis change and a linearized polynomial all fit here.

Tabulated once, each becomes a single instruction per register.

Implementations

impl ByteMatrix

pub const ZERO: Self

The map sending every byte to zero.

pub const IDENTITY: Self

The map leaving every byte alone.

pub const fn from_images(images: [u8; 8]) -> Self

The map sending basis vector 1 << b to entry b of the argument.

A linear map is pinned down by where it sends each of the eight basis vectors.

pub const fn images(self) -> [u8; 8]

Where the map sends each of the eight basis vectors.

pub const fn apply(self, byte: u8) -> u8

The image of one byte.

pub const fn compose(self, first: Self) -> Self

The map applying the argument first and this one second.

pub const fn to_quadword(self) -> u64

The row layout the affine-byte instruction takes as its matrix operand.

pub const fn from_quadword(rows: u64) -> Self

The map already held in that row layout.

Every quadword is a matrix, so this cannot fail.

pub fn apply_slice(self, bytes: &mut [u8])

Replaces every byte of the slice with its image.

Inlined so a caller with a fixed-length block sweeps it without a call.

Trait Implementations

impl Clone for ByteMatrix

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ByteMatrix

impl Debug for ByteMatrix

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

Formats the value using the given formatter.

impl Default for ByteMatrix

fn default() -> Self

Returns the “default value” for a type.

impl Eq for ByteMatrix

impl Hash for ByteMatrix

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ByteMatrix

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ByteMatrix