Struct ContextMap 

pub struct ContextMap { /* private fields */ }

Simple lossy hash table mapping context hashes to state bytes.

Each entry is a single byte (state from StateTable). On collision, the existing entry is silently overwritten.

Implementations

impl ContextMap

pub fn new(size: usize) -> Self

Create a new ContextMap with size entries. size must be a power of 2.

pub fn get(&self, hash: u32) -> u8

Get the current state for a context hash.

pub fn set(&mut self, hash: u32, state: u8)

Set the state for a context hash.

pub fn predict_and_update(&mut self, hash: u32, bit: u8) -> u8

Get state, then update it after observing bit. Returns the state before transition. Also transitions the state in-place.