[][src]Struct rustc_target::abi::TyAndLayout

pub struct TyAndLayout<'a, Ty> {
    pub ty: Ty,
    pub layout: &'a Layout,

The layout of a type, alongside the type itself. Provides various type traversal APIs (e.g., recursing into fields).

Note that the layout is NOT guaranteed to always be identical to that obtained from layout_of(ty), as we need to produce layouts for which Rust types do not exist, such as enum variants or synthetic fields of enums (i.e., discriminants) and fat pointers.


ty: Tylayout: &'a Layout


impl<'a, Ty> TyAndLayout<'a, Ty>[src]

pub(in abi::call) fn is_aggregate(
) -> bool

pub fn homogeneous_aggregate<C>(
    cx: &C
) -> Result<HomogeneousAggregate, Heterogeneous> where
    Ty: TyAndLayoutMethods<'a, C> + Copy,
    C: LayoutOf<Ty = Ty, TyAndLayout = Self>, 

Returns Homogeneous if this layout is an aggregate containing fields of only a single type (e.g., (u32, u32)). Such aggregates are often special-cased in ABIs.

Note: We generally ignore fields of zero-sized type when computing this value (see #56877).

This is public so that it can be used in unit tests, but should generally only be relevant to the ABI details of specific targets.

impl<'a, Ty> TyAndLayout<'a, Ty>[src]

pub fn for_variant<C>(self, cx: &C, variant_index: VariantIdx) -> Self where
    Ty: TyAndLayoutMethods<'a, C>,
    C: LayoutOf<Ty = Ty>, 

pub fn field<C>(self, cx: &C, i: usize) -> C::TyAndLayout where
    Ty: TyAndLayoutMethods<'a, C>,
    C: LayoutOf<Ty = Ty>, 

Callers might want to use C: LayoutOf<Ty=Ty, TyAndLayout: MaybeResult<Self>> to allow recursion (see might_permit_zero_init below for an example).

pub fn pointee_info_at<C>(self, cx: &C, offset: Size) -> Option<PointeeInfo> where
    Ty: TyAndLayoutMethods<'a, C>,
    C: LayoutOf<Ty = Ty>, 

impl<'a, Ty> TyAndLayout<'a, Ty>[src]

pub fn is_unsized(&self) -> bool[src]

Returns true if the layout corresponds to an unsized type.

pub fn is_zst(&self) -> bool[src]

Returns true if the type is a ZST and not unsized.

pub fn might_permit_raw_init<C, E>(self, cx: &C, zero: bool) -> Result<bool, E> where
    Self: Copy,
    Ty: TyAndLayoutMethods<'a, C>,
    C: LayoutOf<Ty = Ty, TyAndLayout: MaybeResult<Self, Error = E>> + HasDataLayout

Determines if this type permits "raw" initialization by just transmuting some memory into an instance of T. zero indicates if the memory is zero-initialized, or alternatively left entirely uninitialized. This is conservative: in doubt, it will answer true.

FIXME: Once we removed all the conservatism, we could alternatively create an all-0/all-undef constant and run the const value validator to see if this is a valid value for the given type.

Methods from Deref<Target = &'a Layout>

Trait Implementations

impl<'a, Ty: Clone> Clone for TyAndLayout<'a, Ty>[src]

impl<'a, Ty: Copy> Copy for TyAndLayout<'a, Ty>[src]

impl<'a, Ty: Debug> Debug for TyAndLayout<'a, Ty>[src]

impl<'a, Ty> Deref for TyAndLayout<'a, Ty>[src]

type Target = &'a Layout

The resulting type after dereferencing.

impl<'a, Ty: Eq> Eq for TyAndLayout<'a, Ty>[src]

impl<'a, Ty: Hash> Hash for TyAndLayout<'a, Ty>[src]

impl<'a, Ty: PartialEq> PartialEq<TyAndLayout<'a, Ty>> for TyAndLayout<'a, Ty>[src]

impl<'a, Ty> StructuralEq for TyAndLayout<'a, Ty>[src]

impl<'a, Ty> StructuralPartialEq for TyAndLayout<'a, Ty>[src]

Auto Trait Implementations

impl<'a, Ty> RefUnwindSafe for TyAndLayout<'a, Ty> where
    Ty: RefUnwindSafe

impl<'a, Ty> Send for TyAndLayout<'a, Ty> where
    Ty: Send

impl<'a, Ty> Sync for TyAndLayout<'a, Ty> where
    Ty: Sync

impl<'a, Ty> Unpin for TyAndLayout<'a, Ty> where
    Ty: Unpin

impl<'a, Ty> UnwindSafe for TyAndLayout<'a, Ty> where
    Ty: UnwindSafe

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized

impl<T> Borrow<T> for T where
    T: ?Sized

impl<T> BorrowMut<T> for T where
    T: ?Sized

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 

impl<T> MaybeResult<T> for T[src]

type Error = !

impl<T> ToOwned for T where
    T: Clone

type Owned = T

The resulting type after obtaining ownership.

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.