Struct LayoutCache 

pub struct LayoutCache { /* private fields */ }

Cached layout plans.

Offsets are invariant under endianness, so an entry serves both byte orders; it is keyed by everything else that moves one, which is LayoutKey::offset_key. Spec §7.

Implementations

impl LayoutCache

pub const fn new() -> Self

Empty cache.

pub fn layout( &mut self, ast: &Ast, type_: Id<TypeNode>, key: LayoutKey, ) -> Result<&TypeLayout, LayoutError>

The plan for a type, computing and caching it on first use.

Errors

Whatever plan returns — an unresolved reference, an unsupported construct, a little-endian key request.

pub fn invalidate(&mut self, changeset: &Changeset)

Evict everything whose plan consulted any node the changeset touched.

Precise rather than wholesale: a change to one type leaves plans for unrelated types in place, and evicts the ones that contain it however deeply. Spec §7.

pub fn clear(&mut self)

Evict every entry.

pub fn len(&self) -> usize

Number of cached plans.

pub fn is_empty(&self) -> bool

Whether nothing is cached.

pub const fn hits(&self) -> u64

How many lookups were served from the cache.

pub const fn misses(&self) -> u64

How many lookups had to compute a plan.

pub fn contains(&self, type_: NodeId, key: LayoutKey) -> bool

Whether a plan for this type and key is cached.

Trait Implementations

impl Clone for LayoutCache

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LayoutCache

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

Formats the value using the given formatter.

impl Default for LayoutCache

fn default() -> Self

Returns the “default value” for a type.