Struct rustc_mir_transform::simplify::UsedLocals

struct UsedLocals {
    increment: bool,
    arg_count: u32,
    use_count: IndexVec<Local, u32>,
}

Keeps track of used & unused locals.

Fields

increment: bool

arg_count: u32

use_count: IndexVec<Local, u32>

Implementations

impl UsedLocals

fn new(body: &Body<'_>) -> Self

Determines which locals are used & unused in the given body.

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

Checks if local is used.

Return place and arguments are always considered used.

fn statement_removed(&mut self, statement: &Statement<'_>)

Updates the use counts to reflect the removal of given statement.

fn visit_lhs(&mut self, place: &Place<'_>, location: Location)

Visits a left-hand side of an assignment.

Trait Implementations

impl<'tcx> Visitor<'tcx> for UsedLocals

fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location)

fn visit_local(&mut self, local: Local, _ctx: PlaceContext, _location: Location)

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

fn visit_basic_block_data(
    &mut self,
    block: BasicBlock,
    data: &BasicBlockData<'tcx>
)

fn visit_source_scope_data(&mut self, scope_data: &SourceScopeData<'tcx>)

fn visit_assign(
    &mut self,
    place: &Place<'tcx>,
    rvalue: &Rvalue<'tcx>,
    location: Location
)

fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location)

fn visit_assert_message(
    &mut self,
    msg: &AssertKind<Operand<'tcx>>,
    location: Location
)

fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location)

fn visit_operand(&mut self, operand: &Operand<'tcx>, location: Location)

fn visit_ascribe_user_ty(
    &mut self,
    place: &Place<'tcx>,
    variance: Variance,
    user_ty: &UserTypeProjection,
    location: Location
)

fn visit_coverage(&mut self, coverage: &Coverage, location: Location)

fn visit_retag(&mut self, kind: RetagKind, place: &Place<'tcx>, location: Location)

fn visit_place(
    &mut self,
    place: &Place<'tcx>,
    context: PlaceContext,
    location: Location
)

fn visit_projection(
    &mut self,
    place_ref: PlaceRef<'tcx>,
    context: PlaceContext,
    location: Location
)

fn visit_projection_elem(
    &mut self,
    local: Local,
    proj_base: &[ProjectionElem<Local, Ty<'tcx>, Ty<'tcx>>],
    elem: ProjectionElem<Local, Ty<'tcx>, Ty<'tcx>>,
    context: PlaceContext,
    location: Location
)

fn super_place(
    &mut self,
    place: &Place<'tcx>,
    context: PlaceContext,
    location: Location
)

fn super_projection(
    &mut self,
    place_ref: PlaceRef<'tcx>,
    context: PlaceContext,
    location: Location
)

fn super_projection_elem(
    &mut self,
    _local: Local,
    _proj_base: &[ProjectionElem<Local, Ty<'tcx>, Ty<'tcx>>],
    elem: ProjectionElem<Local, Ty<'tcx>, Ty<'tcx>>,
    _context: PlaceContext,
    location: Location
)

fn visit_constant(&mut self, constant: &Constant<'tcx>, location: Location)

fn visit_span(&mut self, span: Span)

fn visit_source_info(&mut self, source_info: &SourceInfo)

fn visit_ty(&mut self, ty: Ty<'tcx>, _: TyContext)

fn visit_user_type_projection(&mut self, ty: &UserTypeProjection)

fn visit_user_type_annotation(
    &mut self,
    index: UserTypeAnnotationIndex,
    ty: &CanonicalUserTypeAnnotation<'tcx>
)

fn visit_region(&mut self, region: Region<'tcx>, _: Location)

fn visit_substs(&mut self, substs: &&'tcx List<GenericArg<'tcx>>, _: Location)

fn visit_local_decl(&mut self, local: Local, local_decl: &LocalDecl<'tcx>)

fn visit_var_debug_info(&mut self, var_debug_info: &VarDebugInfo<'tcx>)

fn visit_source_scope(&mut self, scope: SourceScope)

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

fn super_basic_block_data(
    &mut self,
    block: BasicBlock,
    data: &BasicBlockData<'tcx>
)

fn super_source_scope_data(&mut self, scope_data: &SourceScopeData<'tcx>)

fn super_statement(&mut self, statement: &Statement<'tcx>, location: Location)

fn super_assign(
    &mut self,
    place: &Place<'tcx>,
    rvalue: &Rvalue<'tcx>,
    location: Location
)

fn super_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location)

fn super_assert_message(
    &mut self,
    msg: &AssertKind<Operand<'tcx>>,
    location: Location
)

fn super_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location)

fn super_operand(&mut self, operand: &Operand<'tcx>, location: Location)

fn super_ascribe_user_ty(
    &mut self,
    place: &Place<'tcx>,
    _variance: Variance,
    user_ty: &UserTypeProjection,
    location: Location
)

fn super_coverage(&mut self, _coverage: &Coverage, _location: Location)

fn super_retag(
    &mut self,
    _kind: RetagKind,
    place: &Place<'tcx>,
    location: Location
)

fn super_local_decl(&mut self, local: Local, local_decl: &LocalDecl<'tcx>)

fn super_var_debug_info(&mut self, var_debug_info: &VarDebugInfo<'tcx>)

fn super_source_scope(&mut self, _scope: SourceScope)

fn super_constant(&mut self, constant: &Constant<'tcx>, location: Location)

fn super_span(&mut self, _span: Span)

fn super_source_info(&mut self, source_info: &SourceInfo)

fn super_user_type_projection(&mut self, _ty: &UserTypeProjection)

fn super_user_type_annotation(
    &mut self,
    _index: UserTypeAnnotationIndex,
    ty: &CanonicalUserTypeAnnotation<'tcx>
)

fn super_ty(&mut self, _ty: Ty<'tcx>)

fn super_region(&mut self, _region: Region<'tcx>)

fn super_substs(&mut self, _substs: &&'tcx List<GenericArg<'tcx>>)

fn visit_location(&mut self, body: &Body<'tcx>, location: Location)

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: 32 bytes