Struct rustc_ap_rustc_target::abi::TyAndLayout [−][src]
pub struct TyAndLayout<'a, Ty> { pub ty: Ty, pub layout: &'a Layout, }
Expand description
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.
Fields
ty: Ty
layout: &'a Layout
Implementations
pub fn homogeneous_aggregate<C>(
&self,
cx: &C
) -> Result<HomogeneousAggregate, Heterogeneous> where
Ty: TyAndLayoutMethods<'a, C> + Copy,
C: LayoutOf<Ty = Ty, TyAndLayout = Self>,
pub fn homogeneous_aggregate<C>(
&self,
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.
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>,
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>,
Returns true
if the layout corresponds to an unsized type.
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,
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
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
This method tests for !=
.
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
Mutably borrows from an owned value. Read more
Compare self to key
and return true
if they are equal.
Instruments this type with the provided Span
, returning an
Instrumented
wrapper. Read more
type Output = T
type Output = T
Should always be Self
pub fn vzip(self) -> V