Struct PoloniusLivenessContext

pub(crate) struct PoloniusLivenessContext {
    live_region_variances: BTreeMap<RegionVid, ConstraintDirection>,
    pub(crate) boring_nll_locals: FxHashSet<Local>,
}

This struct holds the liveness data created during MIR typeck, and which will be used later in the process, to compute the polonius localized constraints.

Fields

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.

boring_nll_locals: FxHashSet<Local>

The regions that outlive free regions are used to distinguish relevant live locals from boring locals. A boring local is one whose type contains only such regions. Polonius currently has more boring locals than NLLs so we record the latter to use in errors and diagnostics, to focus on the locals we consider relevant and match NLL diagnostics.

Implementations

impl PoloniusLivenessContext

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.

Trait Implementations

impl Default for PoloniusLivenessContext

fn default() -> PoloniusLivenessContext

Returns the “default value” for a type.

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