Struct MaybeRequiresStorage 

pub struct MaybeRequiresStorage {
    killable_locals: FxHashMap<Location, SmallVec<[Local; 4]>>,
}

Dataflow analysis that determines whether each local requires storage at a given location; i.e. whether its storage can go away without being observed.

Fields

killable_locals: FxHashMap<Location, SmallVec<[Local; 4]>>

Used to kill locals that are fully moved and have not been borrowed.

Implementations

impl MaybeRequiresStorage

pub fn new<'tcx>( body: &Body<'tcx>, borrowed_locals: &Results<'tcx, MaybeBorrowedLocals>, ) -> Self

impl MaybeRequiresStorage

fn check_for_move( &self, state: &mut <Self as Analysis<'_>>::Domain, loc: Location, )

Kill locals that are fully moved and have not been borrowed.

Trait Implementations

impl<'tcx> Analysis<'tcx> for MaybeRequiresStorage

const NAME: &'static str = "requires_storage"

A descriptive name for this analysis. Used only for debugging.

type Domain = DenseBitSet<Local>

The type that holds the dataflow state at any given point in the program.

fn bottom_value(&self, body: &Body<'tcx>) -> Self::Domain

Returns the initial value of the dataflow state upon entry to each basic block.

fn initialize_start_block(&self, body: &Body<'tcx>, state: &mut Self::Domain)

Mutates the initial value of the dataflow state upon entry to the START_BLOCK.

fn apply_early_statement_effect( &self, state: &mut Self::Domain, stmt: &Statement<'tcx>, _loc: Location, )

Updates the current dataflow state with an “early” effect, i.e. one that occurs immediately before the given statement.

fn apply_primary_statement_effect( &self, state: &mut Self::Domain, stmt: &Statement<'tcx>, loc: Location, )

Updates the current dataflow state with the effect of evaluating a statement.

fn apply_early_terminator_effect( &self, state: &mut Self::Domain, terminator: &Terminator<'tcx>, _loc: Location, )

Updates the current dataflow state with an effect that occurs immediately before the given terminator.

fn apply_primary_terminator_effect( &self, state: &mut Self::Domain, terminator: &Terminator<'tcx>, loc: Location, )

Updates the current dataflow state with the effect of evaluating a terminator.

fn apply_call_return_effect( &self, state: &mut Self::Domain, _block: BasicBlock, return_places: CallReturnPlaces<'_, 'tcx>, )

Updates the current dataflow state with the effect of a successful return from a Call terminator.

type Direction = Forward

The direction of this analysis. Either Forward or Backward.

type SwitchIntData = !

Auxiliary data used for analyzing SwitchInt terminators, if necessary.

fn apply_effect<'mir>( &self, state: &mut Self::Domain, block: BasicBlock, block_data: &'mir BasicBlockData<'tcx>, idx: EffectIndex, )

Given an EffectIndex, calls the appropriate apply_* method in the {early,primary} x {statement,terminator} space.

fn get_terminator_edges<'mir>( &self, _state: &Self::Domain, terminator: &'mir Terminator<'tcx>, _location: Location, ) -> TerminatorEdges<'mir, 'tcx>

Gets the terminator edges. Used by forward analyses only. Called before apply_primary_terminator_effect is applied; this might seem strange but in practice MaybeInitializedPlaces needs that ordering and other analyses work with either ordering.

fn get_switch_int_data( &self, _block: BasicBlock, _targets: &SwitchTargets, _discr: &Operand<'tcx>, ) -> Option<Self::SwitchIntData>

Used to update the current dataflow state with the effect of taking a particular branch in a SwitchInt terminator.

fn apply_switch_int_edge_effect( &self, _state: &mut Self::Domain, _data: &Self::SwitchIntData, _target_idx: SwitchTargetIndex, )

See comments on get_switch_int_data.

fn iterate_to_fixpoint<'mir>( self, tcx: TyCtxt<'tcx>, body: &'mir Body<'tcx>, pass_name: Option<&'static str>, ) -> Results<'tcx, Self>

where Self: Sized, Self::Domain: DebugWithContext<Self>,

Finds the fixpoint for this dataflow problem.

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: 32 bytes