Struct ValidityVisitor

struct ValidityVisitor<'rt, 'tcx, M: Machine<'tcx>> {
    path: Vec<PathElem>,
    ref_tracking: Option<&'rt mut RefTracking<MPlaceTy<'tcx, M::Provenance>, Vec<PathElem>>>,
    ctfe_mode: Option<CtfeValidationMode>,
    ecx: &'rt mut InterpCx<'tcx, M>,
    reset_provenance_and_padding: bool,
    data_bytes: Option<RangeSet>,
}

Fields

path: Vec<PathElem>

The path may be pushed to, but the part that is present when a function starts must not be changed! visit_fields and visit_array rely on this stack discipline.

ref_tracking: Option<&'rt mut RefTracking<MPlaceTy<'tcx, M::Provenance>, Vec<PathElem>>>

ctfe_mode: Option<CtfeValidationMode>

None indicates this is not validating for CTFE (but for runtime).

ecx: &'rt mut InterpCx<'tcx, M>

reset_provenance_and_padding: bool

Whether provenance should be reset outside of pointers (emulating the effect of a typed copy).

data_bytes: Option<RangeSet>

This tracks which byte ranges in this value contain data; the remaining bytes are padding. The ideal representation here would be pointer-length pairs, but to keep things more compact we only store a (range) set of offsets – the base pointer is the same throughout the entire visit, after all. If this is Some, then reset_provenance_and_padding must be true (but not vice versa: we might not track data vs padding bytes if the operand isn’t stored in memory anyway).

Implementations

impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M>

fn aggregate_field_path_elem( &mut self, layout: TyAndLayout<'tcx>, field: usize, ) -> PathElem

fn with_elem<R>( &mut self, elem: PathElem, f: impl FnOnce(&mut Self) -> InterpResult<'tcx, R>, ) -> InterpResult<'tcx, R>

fn read_immediate( &self, val: &PlaceTy<'tcx, M::Provenance>, expected: ExpectedKind, ) -> InterpResult<'tcx, ImmTy<'tcx, M::Provenance>>

fn read_scalar( &self, val: &PlaceTy<'tcx, M::Provenance>, expected: ExpectedKind, ) -> InterpResult<'tcx, Scalar<M::Provenance>>

fn deref_pointer( &mut self, val: &PlaceTy<'tcx, M::Provenance>, expected: ExpectedKind, ) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>>

fn check_wide_ptr_meta( &mut self, meta: MemPlaceMeta<M::Provenance>, pointee: TyAndLayout<'tcx>, ) -> InterpResult<'tcx>

fn check_safe_pointer( &mut self, value: &PlaceTy<'tcx, M::Provenance>, ptr_kind: PointerKind, ) -> InterpResult<'tcx>

Check a reference or Box.

fn try_visit_primitive( &mut self, value: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx, bool>

Check if this is a value of primitive type, and if yes check the validity of the value at that type. Return true if the type is indeed primitive.

Note that not all of these have FieldsShape::Primitive, e.g. wide references.

fn visit_scalar( &mut self, scalar: Scalar<M::Provenance>, scalar_layout: ScalarAbi, ) -> InterpResult<'tcx>

fn in_mutable_memory(&self, val: &PlaceTy<'tcx, M::Provenance>) -> bool

fn add_data_range(&mut self, ptr: Pointer<Option<M::Provenance>>, size: Size)

Add the given pointer-length pair to the “data” range of this visit.

fn add_data_range_place(&mut self, place: &PlaceTy<'tcx, M::Provenance>)

Add the entire given place to the “data” range of this visit.

fn data_range_offset( ecx: &InterpCx<'tcx, M>, place: &PlaceTy<'tcx, M::Provenance>, ) -> Size

Convert a place into the offset it starts at, for the purpose of data_range tracking. Must only be called if data_bytes is Some(_).

fn reset_padding( &mut self, place: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx>

fn union_data_range<'e>( ecx: &'e mut InterpCx<'tcx, M>, layout: TyAndLayout<'tcx>, ) -> Cow<'e, RangeSet>

Computes the data range of this union type: which bytes are inside a field (i.e., not padding.)

Trait Implementations

impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt, 'tcx, M>

type V = PlaceTy<'tcx, <M as Machine<'tcx>>::Provenance>

fn ecx(&self) -> &InterpCx<'tcx, M>

The visitor must have an InterpCx in it.

fn read_discriminant( &mut self, val: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx, VariantIdx>

read_discriminant can be hooked for better error messages.

fn visit_field( &mut self, old_val: &PlaceTy<'tcx, M::Provenance>, field: usize, new_val: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx>

Called each time we recurse down to a field of a “product-like” aggregate (structs, tuples, arrays and the like, but not enums), passing in old (outer) and new (inner) value. This gives the visitor the chance to track the stack of nested fields that we are descending through.

fn visit_variant( &mut self, old_val: &PlaceTy<'tcx, M::Provenance>, variant_id: VariantIdx, new_val: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx>

Called when recursing into an enum variant. This gives the visitor the chance to track the stack of nested fields that we are descending through.

fn visit_union( &mut self, val: &PlaceTy<'tcx, M::Provenance>, _fields: NonZero<usize>, ) -> InterpResult<'tcx>

Visits the given value as a union. No automatic recursion can happen here.

fn visit_box( &mut self, _box_ty: Ty<'tcx>, val: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx>

Visits the given value as the pointer of a Box. There is nothing to recurse into. The type of v will be a raw pointer to T, but this is a field of Box<T> and the pointee type is the actual T. box_ty provides the full type of the Box itself.

fn visit_value( &mut self, val: &PlaceTy<'tcx, M::Provenance>, ) -> InterpResult<'tcx>

Visits the given value, dispatching as appropriate to more specialized visitors.

fn aggregate_field_iter( memory_index: &IndexVec<FieldIdx, u32>, ) -> impl Iterator<Item = FieldIdx> + 'static

This function provides the chance to reorder the order in which fields are visited for FieldsShape::Aggregate.

fn walk_value(&mut self, v: &Self::V) -> InterpResult<'tcx>

Traversal logic; should not be overloaded.

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: 72 bytes