Enum rustc_middle::mir::StatementKind

pub enum StatementKind<'tcx> {
    Assign(Box<(Place<'tcx>, Rvalue<'tcx>)>),
    FakeRead(FakeReadCause, Box<Place<'tcx>>),
    SetDiscriminant {
        place: Box<Place<'tcx>>,
        variant_index: VariantIdx,
    },
    StorageLive(Local),
    StorageDead(Local),
    LlvmInlineAsm(Box<LlvmInlineAsm<'tcx>>),
    Retag(RetagKind, Box<Place<'tcx>>),
    AscribeUserType(Box<(Place<'tcx>, UserTypeProjection)>, Variance),
    Coverage(Box<Coverage>),
    Nop,
}

Variants

Assign(Box<(Place<'tcx>, Rvalue<'tcx>)>)

Write the RHS Rvalue to the LHS Place.

FakeRead(FakeReadCause, Box<Place<'tcx>>)

This represents all the reading that a pattern match may do (e.g., inspecting constants and discriminant values), and the kind of pattern it comes from. This is in order to adapt potential error messages to these specific patterns.

Note that this also is emitted for regular let bindings to ensure that locals that are never accessed still get some sanity checks for, e.g., let x: ! = ..;

SetDiscriminant

Write the discriminant for a variant to the enum Place.

Fields of SetDiscriminant

place: Box<Place<'tcx>>variant_index: VariantIdx

StorageLive(Local)

Start a live range for the storage of the local.

StorageDead(Local)

End the current live range for the storage of the local.

LlvmInlineAsm(Box<LlvmInlineAsm<'tcx>>)

Executes a piece of inline Assembly. Stored in a Box to keep the size of StatementKind low.

Retag(RetagKind, Box<Place<'tcx>>)

Retag references in the given place, ensuring they got fresh tags. This is part of the Stacked Borrows model. These statements are currently only interpreted by miri and only generated when "-Z mir-emit-retag" is passed. See https://internals.rust-lang.org/t/stacked-borrows-an-aliasing-model-for-rust/8153/ for more details.

AscribeUserType(Box<(Place<'tcx>, UserTypeProjection)>, Variance)

Encodes a user's type ascription. These need to be preserved intact so that NLL can respect them. For example:

let a: T = y;

The effect of this annotation is to relate the type T_y of the place y to the user-given type T. The effect depends on the specified variance:

• Covariant -- requires that T_y <: T
• Contravariant -- requires that T_y :> T
• Invariant -- requires that T_y == T
• Bivariant -- no effect

Coverage(Box<Coverage>)

Marks the start of a "coverage region", injected with '-Zinstrument-coverage'. A CoverageInfo statement carries metadata about the coverage region, used to inject a coverage map into the binary. The Counter kind also generates executable code, to increment a counter varible at runtime, each time the code region is executed.

Nop

No-op. Useful for deleting instructions without affecting statement indices.

Implementations

impl<'tcx> StatementKind<'tcx>

pub fn as_assign_mut(&mut self) -> Option<&mut Box<(Place<'tcx>, Rvalue<'tcx>)>>

Trait Implementations

impl<'tcx> Clone for StatementKind<'tcx>

pub fn clone(&self) -> StatementKind<'tcx>

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'tcx> Debug for StatementKind<'tcx>

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

Formats the value using the given formatter.

impl<'tcx, __D: TyDecoder<'tcx>> Decodable<__D> for StatementKind<'tcx>

pub fn decode(__decoder: &mut __D) -> Result<Self, <__D as Decoder>::Error>

impl<'tcx, __E: TyEncoder<'tcx>> Encodable<__E> for StatementKind<'tcx>

pub fn encode(&self, __encoder: &mut __E) -> Result<(), <__E as Encoder>::Error>

impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for StatementKind<'tcx>

pub fn hash_stable(
    &self,
    __hcx: &mut StableHashingContext<'__ctx>,
    __hasher: &mut StableHasher
)

impl<'tcx> PartialEq<StatementKind<'tcx>> for StatementKind<'tcx>

pub fn eq(&self, other: &StatementKind<'tcx>) -> bool

This method tests for self and other values to be equal, and is used by ==.

pub fn ne(&self, other: &StatementKind<'tcx>) -> bool

This method tests for !=.

impl<'tcx> StructuralPartialEq for StatementKind<'tcx>

impl<'tcx> TypeFoldable<'tcx> for StatementKind<'tcx>

pub fn super_fold_with<__F: TypeFolder<'tcx>>(self, __folder: &mut __F) -> Self

pub fn super_visit_with<__F: TypeVisitor<'tcx>>(
    &self,
    __folder: &mut __F
) -> ControlFlow<__F::BreakTy>

pub fn fold_with<F: TypeFolder<'tcx>>(self, folder: &mut F) -> Self

pub fn visit_with<V: TypeVisitor<'tcx>>(
    &self,
    visitor: &mut V
) -> ControlFlow<V::BreakTy>

pub fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool

Returns true if self has any late-bound regions that are either bound by binder or bound by some binder outside of binder. If binder is ty::INNERMOST, this indicates whether there are any late-bound regions that appear free.

pub fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool

Returns true if this self has any regions that escape binder (and hence are not bound by it).

pub fn has_escaping_bound_vars(&self) -> bool

pub fn has_type_flags(&self, flags: TypeFlags) -> bool

pub fn has_projections(&self) -> bool

pub fn has_opaque_types(&self) -> bool

pub fn references_error(&self) -> bool

pub fn has_param_types_or_consts(&self) -> bool

pub fn has_infer_regions(&self) -> bool

pub fn has_infer_types(&self) -> bool

pub fn has_infer_types_or_consts(&self) -> bool

pub fn needs_infer(&self) -> bool

pub fn has_placeholders(&self) -> bool

pub fn needs_subst(&self) -> bool

pub fn has_free_regions(&self) -> bool

"Free" regions in this context means that it has any region that is not (a) erased or (b) late-bound.

pub fn has_erased_regions(&self) -> bool

pub fn has_erasable_regions(&self) -> bool

True if there are any un-erased free regions.

pub fn is_global(&self) -> bool

Indicates whether this value references only 'global' generic parameters that are the same regardless of what fn we are in. This is used for caching.

pub fn has_late_bound_regions(&self) -> bool

True if there are any late-bound regions

pub fn still_further_specializable(&self) -> bool

Indicates whether this value still has parameters/placeholders/inference variables which could be replaced later, in a way that would change the results of impl specialization.