Struct rustc_mir_transform::dest_prop::Candidates

struct Candidates<'alloc> {
    c: &'alloc mut FxHashMap<Local, Vec<Local>>,
    reverse: &'alloc mut FxHashMap<Local, Vec<Local>>,
}

Fields

c: &'alloc mut FxHashMap<Local, Vec<Local>>

The set of candidates we are considering in this optimization.

We will always merge the key into at most one of its values.

Whether a place ends up in the key or the value does not correspond to whether it appears as the lhs or rhs of any assignment. As a matter of fact, the places in here might never appear in an assignment at all. This happens because if we see an assignment like this:

_1.0 = _2.0

We will still report that we would like to merge _1 and _2 in an attempt to allow us to remove that assignment.

reverse: &'alloc mut FxHashMap<Local, Vec<Local>>

A reverse index of the c set; if the c set contains a => Place { local: b, proj }, then this contains b => a.

Implementations

impl<'alloc> Candidates<'alloc>

fn vec_remove_debug(
    src: Local,
    v: &mut Vec<Local>,
    f: impl FnMut(Local) -> bool,
    at: Location
)

Just Vec::retain, but the condition is inverted and we add debugging output

fn entry_remove(
    entry: OccupiedEntry<'_, Local, Vec<Local>>,
    p: Local,
    f: impl FnMut(Local) -> bool,
    at: Location
)

vec_remove_debug but for an Entry

fn remove_candidates_if(
    &mut self,
    p: Local,
    f: impl FnMut(Local) -> bool,
    at: Location
)

Removes all candidates (p, q) or (q, p) where p is the indicated local and f(q) is true.

Trait Implementations

impl<'alloc> Debug for Candidates<'alloc>

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: 16 bytes