Struct NibbleTables 

pub struct NibbleTables {
    pub tables: [[i8; 16]; 8],
    pub from_hi: [bool; 8],
}

The fused table factored per key position into 16-entry nibble tables, the shape NEON tbl / SSE pshufb consume: one in-register lookup per key position per 16 packed bytes.

Codes of width 1, 2 or 4 never cross a nibble boundary, so key k of a byte is a function of exactly one of its nibbles. The factorisation is verified over all 256 byte values when the Lut is built, so a Packing the tables cannot represent falls back to the scalar path instead of silently diverging from it.

Fields

tables: [[i8; 16]; 8]

Per key position: weights indexed by the source nibble’s value.

from_hi: [bool; 8]

Whether key k reads the byte’s high nibble (else the low one).

Trait Implementations

impl Clone for NibbleTables

fn clone(&self) -> NibbleTables

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NibbleTables

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

Formats the value using the given formatter.

impl Eq for NibbleTables

impl PartialEq for NibbleTables

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for NibbleTables