Struct rustc_mir_dataflow::impls::MaybeInitializedPlaces
source · pub struct MaybeInitializedPlaces<'a, 'mir, 'tcx> {
tcx: TyCtxt<'tcx>,
body: &'mir Body<'tcx>,
move_data: &'a MoveData<'tcx>,
skip_unreachable_unwind: bool,
}
Expand description
MaybeInitializedPlaces
tracks all places that might be
initialized upon reaching a particular point in the control flow
for a function.
For example, in code like the following, we have corresponding dataflow information shown in the right-hand comments.
struct S;
fn foo(pred: bool) { // maybe-init:
// {}
let a = S; let mut b = S; let c; let d; // {a, b}
if pred {
drop(a); // { b}
b = S; // { b}
} else {
drop(b); // {a}
d = S; // {a, d}
} // {a, b, d}
c = S; // {a, b, c, d}
}
To determine whether a place must be initialized at a
particular control-flow point, one can take the set-difference
between this data and the data from MaybeUninitializedPlaces
at the
corresponding control-flow point.
Similarly, at a given drop
statement, the set-intersection
between this data and MaybeUninitializedPlaces
yields the set of
places that would require a dynamic drop-flag at that statement.
Fields§
§tcx: TyCtxt<'tcx>
§body: &'mir Body<'tcx>
§move_data: &'a MoveData<'tcx>
§skip_unreachable_unwind: bool
Implementations§
source§impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx>
pub fn new( tcx: TyCtxt<'tcx>, body: &'mir Body<'tcx>, move_data: &'a MoveData<'tcx>, ) -> Self
pub fn skipping_unreachable_unwind(self) -> Self
pub fn is_unwind_dead( &self, place: Place<'tcx>, state: &MaybeReachable<ChunkedBitSet<MovePathIndex>>, ) -> bool
source§impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx>
fn update_bits( trans: &mut impl GenKill<MovePathIndex>, path: MovePathIndex, state: DropFlagState, )
Trait Implementations§
source§impl<'tcx> AnalysisDomain<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx>
impl<'tcx> AnalysisDomain<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx>
source§type Domain = MaybeReachable<ChunkedBitSet<MovePathIndex>>
type Domain = MaybeReachable<ChunkedBitSet<MovePathIndex>>
There can be many more MovePathIndex
than there are locals in a MIR body.
We use a chunked bitset to avoid paying too high a memory footprint.
source§const NAME: &'static str = "maybe_init"
const NAME: &'static str = "maybe_init"
source§fn bottom_value(&self, _: &Body<'tcx>) -> Self::Domain
fn bottom_value(&self, _: &Body<'tcx>) -> Self::Domain
source§impl<'tcx> GenKillAnalysis<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx>
impl<'tcx> GenKillAnalysis<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx>
type Idx = MovePathIndex
fn domain_size(&self, _: &Body<'tcx>) -> usize
source§fn statement_effect(
&mut self,
trans: &mut impl GenKill<Self::Idx>,
statement: &Statement<'tcx>,
location: Location,
)
fn statement_effect( &mut self, trans: &mut impl GenKill<Self::Idx>, statement: &Statement<'tcx>, location: Location, )
Analysis::apply_statement_effect
. Note how the second arg differs.source§fn terminator_effect<'mir>(
&mut self,
state: &mut Self::Domain,
terminator: &'mir Terminator<'tcx>,
location: Location,
) -> TerminatorEdges<'mir, 'tcx>
fn terminator_effect<'mir>( &mut self, state: &mut Self::Domain, terminator: &'mir Terminator<'tcx>, location: Location, ) -> TerminatorEdges<'mir, 'tcx>
Analysis::apply_terminator_effect
.source§fn call_return_effect(
&mut self,
trans: &mut Self::Domain,
_block: BasicBlock,
return_places: CallReturnPlaces<'_, 'tcx>,
)
fn call_return_effect( &mut self, trans: &mut Self::Domain, _block: BasicBlock, return_places: CallReturnPlaces<'_, 'tcx>, )
Analysis::apply_call_return_effect
.source§fn switch_int_edge_effects<G: GenKill<Self::Idx>>(
&mut self,
block: BasicBlock,
discr: &Operand<'tcx>,
edge_effects: &mut impl SwitchIntEdgeEffects<G>,
)
fn switch_int_edge_effects<G: GenKill<Self::Idx>>( &mut self, block: BasicBlock, discr: &Operand<'tcx>, edge_effects: &mut impl SwitchIntEdgeEffects<G>, )
Analysis::apply_switch_int_edge_effects
.source§fn before_statement_effect(
&mut self,
_trans: &mut impl GenKill<Self::Idx>,
_statement: &Statement<'tcx>,
_location: Location,
)
fn before_statement_effect( &mut self, _trans: &mut impl GenKill<Self::Idx>, _statement: &Statement<'tcx>, _location: Location, )
Analysis::apply_before_statement_effect
. Note how the second arg
differs.source§fn before_terminator_effect(
&mut self,
_trans: &mut Self::Domain,
_terminator: &Terminator<'tcx>,
_location: Location,
)
fn before_terminator_effect( &mut self, _trans: &mut Self::Domain, _terminator: &Terminator<'tcx>, _location: Location, )
Analysis::apply_before_terminator_effect
.source§impl<'a, 'mir, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'mir, 'tcx>
Auto Trait Implementations§
impl<'a, 'mir, 'tcx> Freeze for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> !RefUnwindSafe for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> !Send for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> !Sync for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> Unpin for MaybeInitializedPlaces<'a, 'mir, 'tcx>
impl<'a, 'mir, 'tcx> !UnwindSafe for MaybeInitializedPlaces<'a, 'mir, 'tcx>
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T, R> CollectAndApply<T, R> for T
impl<T, R> CollectAndApply<T, R> for T
source§impl<T> Filterable for T
impl<T> Filterable for T
source§fn filterable(
self,
filter_name: &'static str,
) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>
fn filterable( self, filter_name: &'static str, ) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>
source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§impl<P> IntoQueryParam<P> for P
impl<P> IntoQueryParam<P> for P
fn into_query_param(self) -> P
source§impl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
source§impl<I, T, U> Upcast<I, U> for Twhere
U: UpcastFrom<I, T>,
impl<I, T, U> Upcast<I, U> for Twhere
U: UpcastFrom<I, T>,
source§impl<I, T> UpcastFrom<I, T> for T
impl<I, T> UpcastFrom<I, T> for T
fn upcast_from(from: T, _tcx: I) -> T
source§impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
default fn from_cycle_error( tcx: Tcx, cycle_error: &CycleError, _guar: ErrorGuaranteed, ) -> T
source§impl<T> WithSubscriber for T
impl<T> WithSubscriber for T
source§fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
source§fn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
impl<'a, T> Captures<'a> for Twhere
T: ?Sized,
impl<T> ErasedDestructor for Twhere
T: 'static,
impl<T> MaybeSendSync for T
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