Struct rustc_mir_transform::ssa::SsaLocals

pub struct SsaLocals {
    assignments: IndexVec<Local, Set1<LocationExtended>>,
    assignment_order: Vec<Local>,
    copy_classes: IndexVec<Local, Local>,
}

Fields

assignments: IndexVec<Local, Set1<LocationExtended>>

Assignments to each local. This defines whether the local is SSA.

assignment_order: Vec<Local>

We visit the body in reverse postorder, to ensure each local is assigned before it is used. We remember the order in which we saw the assignments to compute the SSA values in a single pass.

copy_classes: IndexVec<Local, Local>

Copy equivalence classes between locals. See copy_classes for documentation.

Implementations

impl SsaLocals

pub fn new<'tcx>( tcx: TyCtxt<'tcx>, param_env: ParamEnv<'tcx>, body: &Body<'tcx>, borrowed_locals: &BitSet<Local> ) -> SsaLocals

pub fn is_ssa(&self, local: Local) -> bool

pub fn assignments<'a, 'tcx>( &'a self, body: &'a Body<'tcx> ) -> impl Iterator<Item = (Local, &'a Rvalue<'tcx>)> + 'a

pub fn copy_classes(&self) -> &IndexSlice<Local, Local>

Compute the equivalence classes for locals, based on copy statements.

The returned vector maps each local to the one it copies. In the following case: _a = &mut _0 _b = move? _a _c = move? _a _d = move? _c We return the mapping _a => _a // not a copy so, represented by itself _b => _a _c => _a _d => _a // transitively through _c

Exception: we do not see through the return place, as it cannot be substituted.

pub fn meet_copy_equivalence(&self, property: &mut BitSet<Local>)

Make a property uniform on a copy equivalence class by removing elements.

Trait Implementations

impl Debug for SsaLocals

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: 72 bytes