Struct State

struct State {
    values: IndexVec<ValueIndex, FlatSet<Loc>>,
}

The dataflow state for the PointsToAnalysis.

Every instance specifies a lattice that represents the possible values of a single tracked place. If we call this lattice V and set of tracked places P, then a State is an element of {unreachable} ∪ (P -> V). This again forms a lattice, where the bottom element is unreachable and the top element is the mapping p ↦ ⊤. Note that the mapping p ↦ ⊥ is not the bottom element (because joining an unreachable and any other reachable state yields a reachable state). All operations on unreachable states are ignored.

Flooding means assigning a value (by default ⊤) to all tracked projections of a given place.

Fields

values: IndexVec<ValueIndex, FlatSet<Loc>>

Implementations

impl State

fn flood(&mut self, place: PlaceRef<'_>, map: &Map)

fn flood_with(&mut self, place: PlaceRef<'_>, map: &Map, value: FlatSet<Loc>)

fn assign(&mut self, target: PlaceRef<'_>, result: PlaceOrValue, map: &Map)

Helper method to interpret target = result.

fn insert_idx(&mut self, target: PlaceIndex, result: PlaceOrValue, map: &Map)

Low-level method that assigns to a place. This does nothing if the place is not tracked.

The target place must have been flooded before calling this method.

fn insert_place_idx( &mut self, target: PlaceIndex, source: PlaceIndex, map: &Map, )

Copies source to target, including all tracked places beneath.

If target contains a place that is not contained in source, it will be overwritten with Top. Also, because this will copy all entries one after another, it may only be used for places that are non-overlapping or identical.

The target place must have been flooded before calling this method.

fn insert_value_idx( &mut self, target: PlaceIndex, value: FlatSet<Loc>, map: &Map, )

Low-level method that assigns a value to a place. This does nothing if the place is not tracked.

The target place must have been flooded before calling this method.

fn get(&self, place: PlaceRef<'_>, map: &Map) -> FlatSet<Loc>

Retrieve the value stored for a place, or ⊤ if it is not tracked.

fn get_idx(&self, place: PlaceIndex, map: &Map) -> FlatSet<Loc>

Retrieve the value stored for a place index, or ⊤ if it is not tracked.

fn get_tracked_idx(&self, place: PlaceIndex, map: &Map) -> Option<FlatSet<Loc>>

Retrieve the value stored for a place index if tracked

Trait Implementations

impl Clone for State

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for State

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

Formats the value using the given formatter.

impl DebugWithContext<PointsToAnalysis<'_>> for State

This is used to visualize the dataflow analysis.

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

fn fmt_diff_with( &self, old: &Self, ctxt: &PointsToAnalysis<'_>, f: &mut Formatter<'_>, ) -> Result

Print the difference between self and old.

impl JoinSemiLattice for State

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

Computes the least upper bound of two elements, storing the result in self and returning true if self has changed.

impl PartialEq for State

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for State

impl StructuralPartialEq for State