Struct Map 

pub struct Map<'tcx> {
    locals: IndexVec<Local, Option<PlaceIndex>>,
    projections: FxHashMap<(PlaceIndex, TrackElem), PlaceIndex>,
    places: IndexVec<PlaceIndex, PlaceInfo<'tcx>>,
    value_count: usize,
    mode: PlaceCollectionMode,
    inner_values: IndexVec<PlaceIndex, Range<usize>>,
    inner_values_buffer: Vec<ValueIndex>,
}

Partial mapping from Place to PlaceIndex, where some places also have a ValueIndex.

This data structure essentially maintains a tree of places and their projections. Some additional bookkeeping is done, to speed up traversal over this tree:

• For iteration, every PlaceInfo contains an intrusive linked list of its children.
• To directly get the child for a specific projection, there is a projections map.

Fields

locals: IndexVec<Local, Option<PlaceIndex>>

projections: FxHashMap<(PlaceIndex, TrackElem), PlaceIndex>

places: IndexVec<PlaceIndex, PlaceInfo<'tcx>>

value_count: usize

mode: PlaceCollectionMode

inner_values: IndexVec<PlaceIndex, Range<usize>>

inner_values_buffer: Vec<ValueIndex>

Implementations

impl<'tcx> Map<'tcx>

pub fn new( tcx: TyCtxt<'tcx>, body: &Body<'tcx>, mode: PlaceCollectionMode, ) -> Self

Returns a map that only tracks places whose type has scalar layout.

This is currently the only way to create a Map. The way in which the tracked places are chosen is an implementation detail and may not be relied upon (other than that their type are scalars).

fn register_locals(&mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>)

Register all non-excluded places that have scalar layout.

fn collect_places(&mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>)

Collect syntactic places from body, and create PlaceIndex for them.

fn propagate_assignments(&mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>)

Just collecting syntactic places is not enough. We may need to propagate this pattern: _1 = (const 5u32, const 13i64); _2 = _1; _3 = (_2.0 as u32);

_1.0 does not appear, but we still need to track it. This is achieved by propagating projections from assignments. We recorded an assignment between _2 and _1, so we want _1 and _2 to have the same sub-places.

fn create_values( &mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>, value_limit: Option<usize>, )

Create values for places whose type have scalar layout.

fn trim_useless_places(&mut self)

Trim useless places.

pub fn register_place_index( &mut self, ty: Ty<'tcx>, base: PlaceIndex, elem: TrackElem, ) -> PlaceIndex

pub fn register_place( &mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>, place: Place<'tcx>, tail: Option<TrackElem>, ) -> Option<PlaceIndex>

fn register_place_and_discr( &mut self, tcx: TyCtxt<'tcx>, body: &Body<'tcx>, place: Place<'tcx>, ) -> Option<PlaceIndex>

pub fn register_value( &mut self, tcx: TyCtxt<'tcx>, typing_env: TypingEnv<'tcx>, place: PlaceIndex, ) -> Option<ValueIndex>

pub fn register_copy_tree( &mut self, source: PlaceIndex, target: PlaceIndex, f: &mut impl FnMut(ValueIndex, ValueIndex), )

fn cache_preorder_invoke(&mut self, root: PlaceIndex)

Precompute the list of values inside root and store it inside as a slice within inner_values_buffer.

impl<'tcx> Map<'tcx>

pub fn apply(&self, place: PlaceIndex, elem: TrackElem) -> Option<PlaceIndex>

Applies a single projection element, yielding the corresponding child.

fn find_extra( &self, place: PlaceRef<'_>, extra: impl IntoIterator<Item = TrackElem>, ) -> Option<PlaceIndex>

Locates the given place, if it exists in the tree.

pub fn find(&self, place: PlaceRef<'_>) -> Option<PlaceIndex>

Locates the given place, if it exists in the tree.

pub fn find_discr(&self, place: PlaceRef<'_>) -> Option<PlaceIndex>

Locates the given place and applies Discriminant, if it exists in the tree.

pub fn find_len(&self, place: PlaceRef<'_>) -> Option<PlaceIndex>

Locates the given place and applies DerefLen, if it exists in the tree.

pub fn value(&self, place: PlaceIndex) -> Option<ValueIndex>

Locates the value corresponding to the given place.

pub fn find_value(&self, place: PlaceRef<'_>) -> Option<ValueIndex>

Locates the value corresponding to the given place.

pub fn find_discr_value(&self, place: PlaceRef<'_>) -> Option<ValueIndex>

Locates the value corresponding to the given discriminant.

pub fn find_len_value(&self, place: PlaceRef<'_>) -> Option<ValueIndex>

Locates the value corresponding to the given length.

fn children(&self, parent: PlaceIndex) -> impl Iterator<Item = PlaceIndex>

Iterate over all direct children.

pub fn for_each_aliasing_place( &self, place: PlaceRef<'_>, tail_elem: Option<TrackElem>, f: &mut impl FnMut(ValueIndex), )

Invoke a function on the given place and all places that may alias it.

In particular, when the given place has a variant downcast, we invoke the function on all the other variants.

tail_elem allows to support discriminants that are not a place in MIR, but that we track as such.

fn for_each_variant_sibling( &self, parent: PlaceIndex, preserved_child: Option<PlaceIndex>, f: &mut impl FnMut(ValueIndex), )

Invoke the given function on all the descendants of the given place, except one branch.

pub fn values_inside(&self, root: PlaceIndex) -> &[ValueIndex]

Return the range of value indices inside this place.

fn for_each_value_inside( &self, root: PlaceIndex, f: &mut impl FnMut(ValueIndex), )

Invoke a function on each value in the given place and all descendants.

pub fn for_each_projection_value<O>( &self, root: PlaceIndex, value: O, project: &mut impl FnMut(TrackElem, &O) -> Option<O>, f: &mut impl FnMut(PlaceIndex, &O), )

Invoke a function on each value in the given place and all descendants.

pub fn for_each_value_pair( &self, target: PlaceIndex, source: PlaceIndex, f: &mut impl FnMut(ValueIndex, ValueIndex), )

Recursively iterates on each value contained in target, paired with matching projection inside source.

Trait Implementations

impl<'tcx> Debug for Map<'tcx>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

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: 152 bytes