Struct rustc_hir_analysis::check::region::RegionResolutionVisitor
source · struct RegionResolutionVisitor<'tcx> {
tcx: TyCtxt<'tcx>,
expr_and_pat_count: usize,
pessimistic_yield: bool,
fixup_scopes: Vec<Scope>,
scope_tree: ScopeTree,
cx: Context,
terminating_scopes: FxHashSet<ItemLocalId>,
}
Fields§
§tcx: TyCtxt<'tcx>
§expr_and_pat_count: usize
§pessimistic_yield: bool
§fixup_scopes: Vec<Scope>
§scope_tree: ScopeTree
§cx: Context
§terminating_scopes: FxHashSet<ItemLocalId>
terminating_scopes
is a set containing the ids of each
statement, or conditional/repeating expression. These scopes
are calling “terminating scopes” because, when attempting to
find the scope of a temporary, by default we search up the
enclosing scopes until we encounter the terminating scope. A
conditional/repeating expression is one which is not
guaranteed to execute exactly once upon entering the parent
scope. This could be because the expression only executes
conditionally, such as the expression b
in a && b
, or
because the expression may execute many times, such as a loop
body. The reason that we distinguish such expressions is that,
upon exiting the parent scope, we cannot statically know how
many times the expression executed, and thus if the expression
creates temporaries we cannot know statically how many such
temporaries we would have to cleanup. Therefore, we ensure that
the temporaries never outlast the conditional/repeating
expression, preventing the need for dynamic checks and/or
arbitrary amounts of stack space. Terminating scopes end
up being contained in a DestructionScope that contains the
destructor’s execution.
Implementations§
source§impl<'tcx> RegionResolutionVisitor<'tcx>
impl<'tcx> RegionResolutionVisitor<'tcx>
sourcefn record_child_scope(&mut self, child_scope: Scope) -> ScopeDepth
fn record_child_scope(&mut self, child_scope: Scope) -> ScopeDepth
Records the current parent (if any) as the parent of child_scope
.
Returns the depth of child_scope
.
sourcefn enter_scope(&mut self, child_scope: Scope)
fn enter_scope(&mut self, child_scope: Scope)
Records the current parent (if any) as the parent of child_scope
,
and sets child_scope
as the new current parent.
fn enter_node_scope_with_dtor(&mut self, id: ItemLocalId)
fn enter_body(&mut self, hir_id: HirId, f: impl FnOnce(&mut Self))
Trait Implementations§
source§impl<'tcx> Visitor<'tcx> for RegionResolutionVisitor<'tcx>
impl<'tcx> Visitor<'tcx> for RegionResolutionVisitor<'tcx>
fn visit_block(&mut self, b: &'tcx Block<'tcx>)
fn visit_body(&mut self, body: &Body<'tcx>)
fn visit_arm(&mut self, a: &'tcx Arm<'tcx>)
fn visit_pat(&mut self, p: &'tcx Pat<'tcx>)
fn visit_stmt(&mut self, s: &'tcx Stmt<'tcx>)
fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>)
fn visit_local(&mut self, l: &'tcx LetStmt<'tcx>)
type Map = <Self::NestedFilter as NestedFilter<'v>>::Map
source§type NestedFilter = None
type NestedFilter = None
NestedFilter
for details. If you override this type, you
must also override nested_visit_map
. Read moresource§fn nested_visit_map(&mut self) -> Self::Map
fn nested_visit_map(&mut self) -> Self::Map
type NestedFilter
is set to visit nested items, this method
must also be overridden to provide a map to retrieve nested items.source§fn visit_nested_item(&mut self, id: ItemId) -> Self::Result
fn visit_nested_item(&mut self, id: ItemId) -> Self::Result
Self::NestedFilter
is nested_filter::None
, this method does
nothing. You probably don’t want to override this method –
instead, override Self::NestedFilter
or use the “shallow” or
“deep” visit patterns described at
rustc_hir::intravisit
. The only reason to override
this method is if you want a nested pattern but cannot supply a
Map
; see nested_visit_map
for advice.source§fn visit_nested_trait_item(&mut self, id: TraitItemId) -> Self::Result
fn visit_nested_trait_item(&mut self, id: TraitItemId) -> Self::Result
visit_nested_item()
, but for trait items. See
visit_nested_item()
for advice on when to override this
method.source§fn visit_nested_impl_item(&mut self, id: ImplItemId) -> Self::Result
fn visit_nested_impl_item(&mut self, id: ImplItemId) -> Self::Result
visit_nested_item()
, but for impl items. See
visit_nested_item()
for advice on when to override this
method.source§fn visit_nested_foreign_item(&mut self, id: ForeignItemId) -> Self::Result
fn visit_nested_foreign_item(&mut self, id: ForeignItemId) -> Self::Result
visit_nested_item()
, but for foreign items. See
visit_nested_item()
for advice on when to override this
method.source§fn visit_nested_body(&mut self, id: BodyId) -> Self::Result
fn visit_nested_body(&mut self, id: BodyId) -> Self::Result
visit_nested_item
, does nothing by default unless you override
Self::NestedFilter
.fn visit_param(&mut self, param: &'v Param<'v>) -> Self::Result
source§fn visit_item(&mut self, i: &'v Item<'v>) -> Self::Result
fn visit_item(&mut self, i: &'v Item<'v>) -> Self::Result
visit_nested_item
for details.fn visit_id(&mut self, _hir_id: HirId) -> Self::Result
fn visit_name(&mut self, _name: Symbol) -> Self::Result
fn visit_ident(&mut self, ident: Ident) -> Self::Result
fn visit_mod(&mut self, m: &'v Mod<'v>, _s: Span, n: HirId) -> Self::Result
fn visit_foreign_item(&mut self, i: &'v ForeignItem<'v>) -> Self::Result
fn visit_pat_field(&mut self, f: &'v PatField<'v>) -> Self::Result
fn visit_array_length(&mut self, len: &'v ArrayLen<'v>) -> Self::Result
fn visit_anon_const(&mut self, c: &'v AnonConst) -> Self::Result
fn visit_inline_const(&mut self, c: &'v ConstBlock) -> Self::Result
fn visit_const_arg(&mut self, c: &'v ConstArg<'v>) -> Self::Result
fn visit_expr_field(&mut self, field: &'v ExprField<'v>) -> Self::Result
fn visit_ty(&mut self, t: &'v Ty<'v>) -> Self::Result
fn visit_pattern_type_pattern(&mut self, _p: &'v Pat<'v>)
fn visit_generic_param(&mut self, p: &'v GenericParam<'v>) -> Self::Result
fn visit_const_param_default( &mut self, _param: HirId, ct: &'v ConstArg<'v>, ) -> Self::Result
fn visit_generics(&mut self, g: &'v Generics<'v>) -> Self::Result
fn visit_where_predicate( &mut self, predicate: &'v WherePredicate<'v>, ) -> Self::Result
fn visit_fn_ret_ty(&mut self, ret_ty: &'v FnRetTy<'v>) -> Self::Result
fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>) -> Self::Result
fn visit_fn( &mut self, fk: FnKind<'v>, fd: &'v FnDecl<'v>, b: BodyId, _: Span, id: LocalDefId, ) -> Self::Result
fn visit_use( &mut self, path: &'v Path<'v, SmallVec<[Res; 3]>>, hir_id: HirId, ) -> Self::Result
fn visit_trait_item(&mut self, ti: &'v TraitItem<'v>) -> Self::Result
fn visit_trait_item_ref(&mut self, ii: &'v TraitItemRef) -> Self::Result
fn visit_impl_item(&mut self, ii: &'v ImplItem<'v>) -> Self::Result
fn visit_foreign_item_ref(&mut self, ii: &'v ForeignItemRef) -> Self::Result
fn visit_impl_item_ref(&mut self, ii: &'v ImplItemRef) -> Self::Result
fn visit_trait_ref(&mut self, t: &'v TraitRef<'v>) -> Self::Result
fn visit_param_bound(&mut self, bounds: &'v GenericBound<'v>) -> Self::Result
fn visit_precise_capturing_arg( &mut self, arg: &'v PreciseCapturingArg<'v>, ) -> Self::Result
fn visit_poly_trait_ref(&mut self, t: &'v PolyTraitRef<'v>) -> Self::Result
fn visit_variant_data(&mut self, s: &'v VariantData<'v>) -> Self::Result
fn visit_field_def(&mut self, s: &'v FieldDef<'v>) -> Self::Result
fn visit_enum_def( &mut self, enum_definition: &'v EnumDef<'v>, item_id: HirId, ) -> Self::Result
fn visit_variant(&mut self, v: &'v Variant<'v>) -> Self::Result
fn visit_label(&mut self, label: &'v Label) -> Self::Result
fn visit_infer(&mut self, inf: &'v InferArg) -> Self::Result
fn visit_generic_arg(&mut self, generic_arg: &'v GenericArg<'v>) -> Self::Result
fn visit_lifetime(&mut self, lifetime: &'v Lifetime) -> Self::Result
fn visit_qpath( &mut self, qpath: &'v QPath<'v>, id: HirId, _span: Span, ) -> Self::Result
fn visit_path(&mut self, path: &Path<'v>, _id: HirId) -> Self::Result
fn visit_path_segment( &mut self, path_segment: &'v PathSegment<'v>, ) -> Self::Result
fn visit_generic_args( &mut self, generic_args: &'v GenericArgs<'v>, ) -> Self::Result
fn visit_assoc_item_constraint( &mut self, constraint: &'v AssocItemConstraint<'v>, ) -> Self::Result
fn visit_attribute(&mut self, _attr: &'v Attribute) -> Self::Result
fn visit_associated_item_kind( &mut self, kind: &'v AssocItemKind, ) -> Self::Result
fn visit_defaultness(&mut self, defaultness: &'v Defaultness) -> Self::Result
fn visit_inline_asm( &mut self, asm: &'v InlineAsm<'v>, id: HirId, ) -> Self::Result
Auto Trait Implementations§
impl<'tcx> Freeze for RegionResolutionVisitor<'tcx>
impl<'tcx> !RefUnwindSafe for RegionResolutionVisitor<'tcx>
impl<'tcx> !Send for RegionResolutionVisitor<'tcx>
impl<'tcx> !Sync for RegionResolutionVisitor<'tcx>
impl<'tcx> Unpin for RegionResolutionVisitor<'tcx>
impl<'tcx> !UnwindSafe for RegionResolutionVisitor<'tcx>
Blanket Implementations§
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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
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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>
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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
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fn into_query_param(self) -> P
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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: 312 bytes