Enum rustc_const_eval::interpret::Immediate

pub enum Immediate<Prov: Provenance = AllocId> {
    Scalar(Scalar<Prov>),
    ScalarPair(Scalar<Prov>, Scalar<Prov>),
    Uninit,
}

An Immediate represents a single immediate self-contained Rust value.

For optimization of a few very common cases, there is also a representation for a pair of primitive values (ScalarPair). It allows Miri to avoid making allocations for checked binary operations and wide pointers. This idea was taken from rustc’s codegen. In particular, thanks to ScalarPair, arithmetic operations and casts can be entirely defined on Immediate, and do not have to work with a Place.

Variants

Scalar(Scalar<Prov>)

A single scalar value (must have initialized Scalar ABI).

ScalarPair(Scalar<Prov>, Scalar<Prov>)

A pair of two scalar value (must have ScalarPair ABI where both fields are Scalar::Initialized).

Uninit

A value of fully uninitialized memory. Can have and size and layout.

Implementations

impl<Prov: Provenance> Immediate<Prov>

pub fn from_pointer(p: Pointer<Prov>, cx: &impl HasDataLayout) -> Self

pub fn from_maybe_pointer( p: Pointer<Option<Prov>>, cx: &impl HasDataLayout ) -> Self

pub fn new_slice(val: Scalar<Prov>, len: u64, cx: &impl HasDataLayout) -> Self

pub fn new_dyn_trait( val: Scalar<Prov>, vtable: Pointer<Option<Prov>>, cx: &impl HasDataLayout ) -> Self

pub fn to_scalar(self) -> Scalar<Prov>

pub fn to_scalar_pair(self) -> (Scalar<Prov>, Scalar<Prov>)

Trait Implementations

impl<Prov: Clone + Provenance> Clone for Immediate<Prov>

fn clone(&self) -> Immediate<Prov>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<Prov: Debug + Provenance> Debug for Immediate<Prov>

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

Formats the value using the given formatter.

impl<Prov: Provenance> From<Scalar<Prov>> for Immediate<Prov>

fn from(val: Scalar<Prov>) -> Self

Converts to this type from the input type.

impl<Prov: Copy + Provenance> Copy for Immediate<Prov>

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.