Enum rustc_middle::mir::interpret::Scalar

pub enum Scalar<Tag = ()> {
    Raw {
        data: u128,
        size: u8,
    },
    Ptr(Pointer<Tag>),
}

A Scalar represents an immediate, primitive value existing outside of a memory::Allocation. It is in many ways like a small chunk of a Allocation, up to 8 bytes in size. Like a range of bytes in an Allocation, a Scalar can either represent the raw bytes of a simple value or a pointer into another Allocation

Variants

Raw

The raw bytes of a simple value.

Fields of Raw

data: u128

The first size bytes of data are the value. Do not try to read less or more bytes than that. The remaining bytes must be 0.

size: u8

Ptr(Pointer<Tag>)

A pointer into an Allocation. An Allocation in the memory module has a list of relocations, but a Scalar is only large enough to contain one, so we just represent the relocation and its associated offset together as a Pointer here.

Implementations

impl Scalar<()>

fn check_data(data: u128, size: u8)

Make sure the data fits in size. This is guaranteed by all constructors here, but since the enum variants are public, it could still be violated (even though no code outside this file should construct Scalars).

pub fn with_tag<Tag>(self, new_tag: Tag) -> Scalar<Tag>

Tag this scalar with new_tag if it is a pointer, leave it unchanged otherwise.

Used by MemPlace::replace_tag.

impl<'tcx, Tag> Scalar<Tag>

pub fn erase_tag(self) -> Scalar

Erase the tag from the scalar, if any.

Used by error reporting code to avoid having the error type depend on Tag.

pub fn null_ptr(cx: &impl HasDataLayout) -> Self

pub fn zst() -> Self

fn ptr_op(
    self,
    dl: &TargetDataLayout,
    f_int: impl FnOnce(u64) -> InterpResult<'tcx, u64>,
    f_ptr: impl FnOnce(Pointer<Tag>) -> InterpResult<'tcx, Pointer<Tag>>
) -> InterpResult<'tcx, Self>

pub fn ptr_offset(
    self,
    i: Size,
    cx: &impl HasDataLayout
) -> InterpResult<'tcx, Self>

pub fn ptr_wrapping_offset(self, i: Size, cx: &impl HasDataLayout) -> Self

pub fn ptr_signed_offset(
    self,
    i: i64,
    cx: &impl HasDataLayout
) -> InterpResult<'tcx, Self>

pub fn ptr_wrapping_signed_offset(self, i: i64, cx: &impl HasDataLayout) -> Self

pub fn from_bool(b: bool) -> Self

pub fn from_char(c: char) -> Self

pub fn try_from_uint(i: impl Into<u128>, size: Size) -> Option<Self>

pub fn from_uint(i: impl Into<u128>, size: Size) -> Self

pub fn from_u8(i: u8) -> Self

pub fn from_u16(i: u16) -> Self

pub fn from_u32(i: u32) -> Self

pub fn from_u64(i: u64) -> Self

pub fn from_machine_usize(i: u64, cx: &impl HasDataLayout) -> Self

pub fn try_from_int(i: impl Into<i128>, size: Size) -> Option<Self>

pub fn from_int(i: impl Into<i128>, size: Size) -> Self

pub fn from_i8(i: i8) -> Self

pub fn from_i16(i: i16) -> Self

pub fn from_i32(i: i32) -> Self

pub fn from_i64(i: i64) -> Self

pub fn from_machine_isize(i: i64, cx: &impl HasDataLayout) -> Self

pub fn from_f32(f: Single) -> Self

pub fn from_f64(f: Double) -> Self

pub fn to_bits_or_ptr(
    self,
    target_size: Size,
    cx: &impl HasDataLayout
) -> Result<u128, Pointer<Tag>>

This is very rarely the method you want! You should dispatch on the type and use force_bits/assert_bits/force_ptr/assert_ptr. This method only exists for the benefit of low-level memory operations as well as the implementation of the force_* methods.

fn to_bits(self, target_size: Size) -> InterpResult<'tcx, u128>

This method is intentionally private! It is just a helper for other methods in this file.

pub fn assert_bits(self, target_size: Size) -> u128

pub fn assert_ptr(self) -> Pointer<Tag>

pub fn is_bits(self) -> bool

Do not call this method! Dispatch based on the type instead.

pub fn is_ptr(self) -> bool

Do not call this method! Dispatch based on the type instead.

pub fn to_bool(self) -> InterpResult<'tcx, bool>

pub fn to_char(self) -> InterpResult<'tcx, char>

fn to_unsigned_with_bit_width(self, bits: u64) -> InterpResult<'static, u128>

pub fn to_u8(self) -> InterpResult<'static, u8>

Converts the scalar to produce an u8. Fails if the scalar is a pointer.

pub fn to_u16(self) -> InterpResult<'static, u16>

Converts the scalar to produce an u16. Fails if the scalar is a pointer.

pub fn to_u32(self) -> InterpResult<'static, u32>

Converts the scalar to produce an u32. Fails if the scalar is a pointer.

pub fn to_u64(self) -> InterpResult<'static, u64>

Converts the scalar to produce an u64. Fails if the scalar is a pointer.

pub fn to_machine_usize(
    self,
    cx: &impl HasDataLayout
) -> InterpResult<'static, u64>

fn to_signed_with_bit_width(self, bits: u64) -> InterpResult<'static, i128>

pub fn to_i8(self) -> InterpResult<'static, i8>

Converts the scalar to produce an i8. Fails if the scalar is a pointer.

pub fn to_i16(self) -> InterpResult<'static, i16>

Converts the scalar to produce an i16. Fails if the scalar is a pointer.

pub fn to_i32(self) -> InterpResult<'static, i32>

Converts the scalar to produce an i32. Fails if the scalar is a pointer.

pub fn to_i64(self) -> InterpResult<'static, i64>

Converts the scalar to produce an i64. Fails if the scalar is a pointer.

pub fn to_machine_isize(
    self,
    cx: &impl HasDataLayout
) -> InterpResult<'static, i64>

pub fn to_f32(self) -> InterpResult<'static, Single>

pub fn to_f64(self) -> InterpResult<'static, Double>

Trait Implementations

impl<Tag: Clone> Clone for Scalar<Tag>

fn clone(&self) -> Scalar<Tag>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<Tag: Copy> Copy for Scalar<Tag>

impl<Tag: Debug> Debug for Scalar<Tag>

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

Formats the value using the given formatter.

impl<'tcx, Tag, __D: TyDecoder<'tcx>> Decodable<__D> for Scalar<Tag> where
    Tag: Decodable<__D>, 

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

impl<Tag: Debug> Display for Scalar<Tag>

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

Formats the value using the given formatter.

impl<'tcx, Tag, __E: TyEncoder<'tcx>> Encodable<__E> for Scalar<Tag> where
    Tag: Encodable<__E>, 

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

impl<Tag: Eq> Eq for Scalar<Tag>

impl<Tag> From<IeeeFloat<DoubleS>> for Scalar<Tag>

fn from(f: Double) -> Self

Performs the conversion.

impl<Tag> From<IeeeFloat<SingleS>> for Scalar<Tag>

fn from(f: Single) -> Self

Performs the conversion.

impl<Tag> From<Pointer<Tag>> for Scalar<Tag>

fn from(ptr: Pointer<Tag>) -> Self

Performs the conversion.

impl<Tag> From<Scalar<Tag>> for ScalarMaybeUninit<Tag>

fn from(s: Scalar<Tag>) -> Self

Performs the conversion.

impl<Tag: Hash> Hash for Scalar<Tag>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<'__ctx, Tag> HashStable<StableHashingContext<'__ctx>> for Scalar<Tag> where
    Tag: HashStable<StableHashingContext<'__ctx>>, 

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

impl<Tag: Ord> Ord for Scalar<Tag>

fn cmp(&self, other: &Scalar<Tag>) -> Ordering

This method returns an [Ordering] between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<Tag: PartialEq> PartialEq<Scalar<Tag>> for Scalar<Tag>

fn eq(&self, other: &Scalar<Tag>) -> bool

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

fn ne(&self, other: &Scalar<Tag>) -> bool

This method tests for !=.

impl<Tag: PartialOrd> PartialOrd<Scalar<Tag>> for Scalar<Tag>

fn partial_cmp(&self, other: &Scalar<Tag>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Scalar<Tag>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Scalar<Tag>) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Scalar<Tag>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Scalar<Tag>) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<Tag> StructuralEq for Scalar<Tag>

impl<Tag> StructuralPartialEq for Scalar<Tag>