Struct PoloniusContext

pub(crate) struct PoloniusContext {
    live_regions: Option<SparseBitMatrix<PointIndex, RegionVid>>,
    live_region_variances: BTreeMap<RegionVid, ConstraintDirection>,
}

This struct holds the data needed to create the Polonius localized constraints.

Fields

live_regions: Option<SparseBitMatrix<PointIndex, RegionVid>>

The set of regions that are live at a given point in the CFG, used to create localized outlives constraints between regions that are live at connected points in the CFG.

live_region_variances: BTreeMap<RegionVid, ConstraintDirection>

The expected edge direction per live region: the kind of directed edge we’ll create as liveness constraints depends on the variance of types with respect to each contained region.

Implementations

impl PoloniusContext

pub(crate) fn record_live_region_variance<'tcx>( &mut self, tcx: TyCtxt<'tcx>, universal_regions: &UniversalRegions<'tcx>, value: impl TypeVisitable<TyCtxt<'tcx>> + Relate<TyCtxt<'tcx>>, )

Record the variance of each region contained within the given value.

pub(crate) fn record_live_regions_per_point( &mut self, num_regions: usize, points_per_live_region: &SparseIntervalMatrix<RegionVid, PointIndex>, )

Unlike NLLs, in polonius we traverse the cfg to look for regions live across an edge, so we need to transpose the “points where each region is live” matrix to a “live regions per point” matrix.

impl PoloniusContext

pub(crate) fn new() -> PoloniusContext

pub(crate) fn create_localized_constraints<'tcx>( &self, tcx: TyCtxt<'tcx>, regioncx: &RegionInferenceContext<'tcx>, body: &Body<'tcx>, ) -> LocalizedOutlivesConstraintSet

Creates a constraint set for -Zpolonius=next by:

• converting NLL typeck constraints to be localized
• encoding liveness constraints

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 56 bytes