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pub use Integer::*;
pub use Primitive::*;
use crate::json::{Json, ToJson};
use std::ops::Deref;
use rustc_macros::HashStable_Generic;
pub mod call;
pub use rustc_abi::*;
impl ToJson for Endian {
fn to_json(&self) -> Json {
self.as_str().to_json()
}
}
/// 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.
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable_Generic)]
pub struct TyAndLayout<'a, Ty> {
pub ty: Ty,
pub layout: Layout<'a>,
}
impl<'a, Ty> Deref for TyAndLayout<'a, Ty> {
type Target = &'a LayoutS;
fn deref(&self) -> &&'a LayoutS {
&self.layout.0.0
}
}
/// Trait that needs to be implemented by the higher-level type representation
/// (e.g. `rustc_middle::ty::Ty`), to provide `rustc_target::abi` functionality.
pub trait TyAbiInterface<'a, C>: Sized {
fn ty_and_layout_for_variant(
this: TyAndLayout<'a, Self>,
cx: &C,
variant_index: VariantIdx,
) -> TyAndLayout<'a, Self>;
fn ty_and_layout_field(this: TyAndLayout<'a, Self>, cx: &C, i: usize) -> TyAndLayout<'a, Self>;
fn ty_and_layout_pointee_info_at(
this: TyAndLayout<'a, Self>,
cx: &C,
offset: Size,
) -> Option<PointeeInfo>;
fn is_adt(this: TyAndLayout<'a, Self>) -> bool;
fn is_never(this: TyAndLayout<'a, Self>) -> bool;
fn is_tuple(this: TyAndLayout<'a, Self>) -> bool;
fn is_unit(this: TyAndLayout<'a, Self>) -> bool;
}
impl<'a, Ty> TyAndLayout<'a, Ty> {
pub fn for_variant<C>(self, cx: &C, variant_index: VariantIdx) -> Self
where
Ty: TyAbiInterface<'a, C>,
{
Ty::ty_and_layout_for_variant(self, cx, variant_index)
}
pub fn field<C>(self, cx: &C, i: usize) -> Self
where
Ty: TyAbiInterface<'a, C>,
{
Ty::ty_and_layout_field(self, cx, i)
}
pub fn pointee_info_at<C>(self, cx: &C, offset: Size) -> Option<PointeeInfo>
where
Ty: TyAbiInterface<'a, C>,
{
Ty::ty_and_layout_pointee_info_at(self, cx, offset)
}
pub fn is_single_fp_element<C>(self, cx: &C) -> bool
where
Ty: TyAbiInterface<'a, C>,
C: HasDataLayout,
{
match self.abi {
Abi::Scalar(scalar) => matches!(scalar.primitive(), F32 | F64),
Abi::Aggregate { .. } => {
if self.fields.count() == 1 && self.fields.offset(0).bytes() == 0 {
self.field(cx, 0).is_single_fp_element(cx)
} else {
false
}
}
_ => false,
}
}
pub fn is_adt<C>(self) -> bool
where
Ty: TyAbiInterface<'a, C>,
{
Ty::is_adt(self)
}
pub fn is_never<C>(self) -> bool
where
Ty: TyAbiInterface<'a, C>,
{
Ty::is_never(self)
}
pub fn is_tuple<C>(self) -> bool
where
Ty: TyAbiInterface<'a, C>,
{
Ty::is_tuple(self)
}
pub fn is_unit<C>(self) -> bool
where
Ty: TyAbiInterface<'a, C>,
{
Ty::is_unit(self)
}
}
impl<'a, Ty> TyAndLayout<'a, Ty> {
/// Returns `true` if the layout corresponds to an unsized type.
pub fn is_unsized(&self) -> bool {
self.abi.is_unsized()
}
#[inline]
pub fn is_sized(&self) -> bool {
self.abi.is_sized()
}
/// Returns `true` if the type is a ZST and not unsized.
pub fn is_zst(&self) -> bool {
match self.abi {
Abi::Scalar(_) | Abi::ScalarPair(..) | Abi::Vector { .. } => false,
Abi::Uninhabited => self.size.bytes() == 0,
Abi::Aggregate { sized } => sized && self.size.bytes() == 0,
}
}
}
|
