Struct rustc_trait_selection::solve::search_graph::ProvisionalCacheEntry

source ·

struct ProvisionalCacheEntry<'tcx> {
    stack_depth: Option<StackDepth>,
    with_inductive_stack: Option<DetachedEntry<'tcx>>,
    with_coinductive_stack: Option<DetachedEntry<'tcx>>,
}

Expand description

Stores the stack depth of a currently evaluated goal and already computed results for goals which depend on other goals still on the stack.

The provisional result may depend on whether the stack above it is inductive or coinductive. Because of this, we store separate provisional results for each case. If an provisional entry is not applicable, it may be the case that we already have provisional result while computing a goal. In this case we prefer the provisional result to potentially avoid fixpoint iterations. See tests/ui/traits/next-solver/cycles/mixed-cycles-2.rs for an example.

The provisional cache can theoretically result in changes to the observable behavior, see tests/ui/traits/next-solver/cycles/provisional-cache-impacts-behavior.rs.

Fields§

§stack_depth: Option<StackDepth>§with_inductive_stack: Option<DetachedEntry<'tcx>>§with_coinductive_stack: Option<DetachedEntry<'tcx>>

Struct rustc_trait_selection::solve::search_graph::ProvisionalCacheEntry

Fields§

Implementations§

impl<'tcx> ProvisionalCacheEntry<'tcx>

fn is_empty(&self) -> bool

Trait Implementations§

impl<'tcx> Default for ProvisionalCacheEntry<'tcx>

fn default() -> ProvisionalCacheEntry<'tcx>

Auto Trait Implementations§

impl<'tcx> DynSend for ProvisionalCacheEntry<'tcx>

impl<'tcx> DynSync for ProvisionalCacheEntry<'tcx>

impl<'tcx> Freeze for ProvisionalCacheEntry<'tcx>

impl<'tcx> !RefUnwindSafe for ProvisionalCacheEntry<'tcx>

impl<'tcx> Send for ProvisionalCacheEntry<'tcx>

impl<'tcx> Sync for ProvisionalCacheEntry<'tcx>

impl<'tcx> Unpin for ProvisionalCacheEntry<'tcx>

impl<'tcx> !UnwindSafe for ProvisionalCacheEntry<'tcx>

Blanket Implementations§

impl<T> Aligned for T

const ALIGN: Alignment = _

impl<T> Any for Twhere T: 'static + ?Sized,

fn type_id(&self) -> TypeId

impl<T> Borrow<T> for Twhere T: ?Sized,

fn borrow(&self) -> &T

impl<T> BorrowMut<T> for Twhere T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

impl<T, R> CollectAndApply<T, R> for T

fn collect_and_apply<I, F>(iter: I, f: F) -> Rwhere I: Iterator<Item = T>, F: FnOnce(&[T]) -> R,

type Output = R

impl<T> Filterable for T

fn filterable( self, filter_name: &'static str ) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>

impl<T> From<T> for T

fn from(t: T) -> T

impl<T> Instrument for T

fn instrument(self, span: Span) -> Instrumented<Self>

fn in_current_span(self) -> Instrumented<Self>

impl<T, U> Into<U> for Twhere U: From<T>,

fn into(self) -> U

impl<P> IntoQueryParam<P> for P

fn into_query_param(self) -> P

impl<T> MaybeResult<T> for T

type Error = !

fn from(_: Result<T, <T as MaybeResult<T>>::Error>) -> T

fn to_result(self) -> Result<T, <T as MaybeResult<T>>::Error>

impl<T> Pointable for T

const ALIGN: usize = _

type Init = T

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

unsafe fn drop(ptr: usize)

impl<T> Same for T

type Output = T

impl<'tcx, T> ToPredicate<'tcx, T> for T

fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T

impl<T, U> TryFrom<U> for Twhere U: Into<T>,

type Error = Infallible

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

impl<V, T> VZip<V> for Twhere V: MultiLane<T>,

fn vzip(self) -> V

impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,

default fn from_cycle_error( tcx: Tcx, cycle_error: &CycleError, _guar: ErrorGuaranteed ) -> T

impl<T> WithSubscriber for T

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>where S: Into<Dispatch>,

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 Twhere T: Send + Sync,

Layout§

impl<T> Any for T
where T: 'static + ?Sized,

impl<T> Borrow<T> for T
where T: ?Sized,

impl<T> BorrowMut<T> for T
where T: ?Sized,

fn collect_and_apply<I, F>(iter: I, f: F) -> R
where I: Iterator<Item = T>, F: FnOnce(&[T]) -> R,

impl<T, U> Into<U> for T
where U: From<T>,

impl<T, U> TryFrom<U> for T
where U: Into<T>,

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

impl<V, T> VZip<V> for T
where V: MultiLane<T>,

impl<Tcx, T> Value<Tcx> for T
where Tcx: DepContext,

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

impl<'a, T> Captures<'a> for T
where T: ?Sized,

impl<T> ErasedDestructor for T
where T: 'static,

impl<T> MaybeSendSync for T
where T: Send + Sync,