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rust/rust/fc5a7077ca43894de1ea0d3f9f56ac627ceef5c7/./compiler/rustc_middle/src/ty/sty.rs
blob: 0d047b348d9e12d942be338f55396b5f44bc0396 [file]
//! This module contains `TyKind` and its major components.
#![allow(rustc::usage_of_ty_tykind)]
use std::borrow::Cow;
use std::debug_assert_matches;
use std::ops::{ControlFlow, Range};
use hir::def::{CtorKind, DefKind};
use rustc_abi::{FIRST_VARIANT, FieldIdx, ScalableElt, VariantIdx};
use rustc_errors::{ErrorGuaranteed, MultiSpan};
use rustc_hir as hir;
use rustc_hir::LangItem;
use rustc_hir::def_id::DefId;
use rustc_macros::{HashStable, TyDecodable, TyEncodable, TypeFoldable, extension};
use rustc_span::{DUMMY_SP, Span, Symbol, kw, sym};
use rustc_type_ir::TyKind::*;
use rustc_type_ir::solve::SizedTraitKind;
use rustc_type_ir::walk::TypeWalker;
use rustc_type_ir::{self as ir, BoundVar, CollectAndApply, TypeVisitableExt, elaborate};
use tracing::instrument;
use ty::util::IntTypeExt;
use super::GenericParamDefKind;
use crate::infer::canonical::Canonical;
use crate::traits::ObligationCause;
use crate::ty::InferTy::*;
use crate::ty::{
self, AdtDef, Const, Discr, GenericArg, GenericArgs, GenericArgsRef, List, ParamEnv, Region,
Ty, TyCtxt, TypeFlags, TypeSuperVisitable, TypeVisitable, TypeVisitor, UintTy, ValTree,
};
// Re-export and re-parameterize some `I = TyCtxt<'tcx>` types here
#[rustc_diagnostic_item = "TyKind"]
pub type TyKind<'tcx> = ir::TyKind<TyCtxt<'tcx>>;
pub type TypeAndMut<'tcx> = ir::TypeAndMut<TyCtxt<'tcx>>;
pub type AliasTy<'tcx> = ir::AliasTy<TyCtxt<'tcx>>;
pub type FnSig<'tcx> = ir::FnSig<TyCtxt<'tcx>>;
pub type Binder<'tcx, T> = ir::Binder<TyCtxt<'tcx>, T>;
pub type EarlyBinder<'tcx, T> = ir::EarlyBinder<TyCtxt<'tcx>, T>;
pub type TypingMode<'tcx> = ir::TypingMode<TyCtxt<'tcx>>;
pub type Placeholder<'tcx, T> = ir::Placeholder<TyCtxt<'tcx>, T>;
pub type PlaceholderRegion<'tcx> = ir::PlaceholderRegion<TyCtxt<'tcx>>;
pub type PlaceholderType<'tcx> = ir::PlaceholderType<TyCtxt<'tcx>>;
pub type PlaceholderConst<'tcx> = ir::PlaceholderConst<TyCtxt<'tcx>>;
pub type BoundTy<'tcx> = ir::BoundTy<TyCtxt<'tcx>>;
pub type BoundConst<'tcx> = ir::BoundConst<TyCtxt<'tcx>>;
pub type BoundRegion<'tcx> = ir::BoundRegion<TyCtxt<'tcx>>;
pub type BoundVariableKind<'tcx> = ir::BoundVariableKind<TyCtxt<'tcx>>;
pub type BoundRegionKind<'tcx> = ir::BoundRegionKind<TyCtxt<'tcx>>;
pub type BoundTyKind<'tcx> = ir::BoundTyKind<TyCtxt<'tcx>>;
pub trait Article {
fn article(&self) -> &'static str;
}
impl<'tcx> Article for TyKind<'tcx> {
/// Get the article ("a" or "an") to use with this type.
fn article(&self) -> &'static str {
match self {
Int(_) | Float(_) | Array(_, _) => "an",
Adt(def, _) if def.is_enum() => "an",
// This should never happen, but ICEing and causing the user's code
// to not compile felt too harsh.
Error(_) => "a",
_ => "a",
}
}
}
#[extension(pub trait CoroutineArgsExt<'tcx>)]
impl<'tcx> ty::CoroutineArgs<TyCtxt<'tcx>> {
/// Coroutine has not been resumed yet.
const UNRESUMED: usize = 0;
/// Coroutine has returned or is completed.
const RETURNED: usize = 1;
/// Coroutine has been poisoned.
const POISONED: usize = 2;
/// Number of variants to reserve in coroutine state. Corresponds to
/// `UNRESUMED` (beginning of a coroutine) and `RETURNED`/`POISONED`
/// (end of a coroutine) states.
const RESERVED_VARIANTS: usize = 3;
const UNRESUMED_NAME: &'static str = "Unresumed";
const RETURNED_NAME: &'static str = "Returned";
const POISONED_NAME: &'static str = "Panicked";
/// The valid variant indices of this coroutine.
#[inline]
fn variant_range(&self, def_id: DefId, tcx: TyCtxt<'tcx>) -> Range<VariantIdx> {
// FIXME requires optimized MIR
FIRST_VARIANT..tcx.coroutine_layout(def_id, self.args).unwrap().variant_fields.next_index()
}
/// The discriminant for the given variant. Panics if the `variant_index` is
/// out of range.
#[inline]
fn discriminant_for_variant(
&self,
def_id: DefId,
tcx: TyCtxt<'tcx>,
variant_index: VariantIdx,
) -> Discr<'tcx> {
// Coroutines don't support explicit discriminant values, so they are
// the same as the variant index.
assert!(self.variant_range(def_id, tcx).contains(&variant_index));
Discr { val: variant_index.as_usize() as u128, ty: self.discr_ty(tcx) }
}
/// The set of all discriminants for the coroutine, enumerated with their
/// variant indices.
#[inline]
fn discriminants(
self,
def_id: DefId,
tcx: TyCtxt<'tcx>,
) -> impl Iterator<Item = (VariantIdx, Discr<'tcx>)> {
self.variant_range(def_id, tcx).map(move |index| {
(index, Discr { val: index.as_usize() as u128, ty: self.discr_ty(tcx) })
})
}
/// Calls `f` with a reference to the name of the enumerator for the given
/// variant `v`.
fn variant_name(v: VariantIdx) -> Cow<'static, str> {
match v.as_usize() {
Self::UNRESUMED => Cow::from(Self::UNRESUMED_NAME),
Self::RETURNED => Cow::from(Self::RETURNED_NAME),
Self::POISONED => Cow::from(Self::POISONED_NAME),
_ => Cow::from(format!("Suspend{}", v.as_usize() - Self::RESERVED_VARIANTS)),
}
}
/// The type of the state discriminant used in the coroutine type.
#[inline]
fn discr_ty(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
tcx.types.u32
}
/// This returns the types of the MIR locals which had to be stored across suspension points.
/// It is calculated in rustc_mir_transform::coroutine::StateTransform.
/// All the types here must be in the tuple in CoroutineInterior.
///
/// The locals are grouped by their variant number. Note that some locals may
/// be repeated in multiple variants.
#[inline]
fn state_tys(
self,
def_id: DefId,
tcx: TyCtxt<'tcx>,
) -> impl Iterator<Item: Iterator<Item = Ty<'tcx>>> {
let layout = tcx.coroutine_layout(def_id, self.args).unwrap();
layout.variant_fields.iter().map(move |variant| {
variant.iter().map(move |field| {
if tcx.is_async_drop_in_place_coroutine(def_id) {
layout.field_tys[*field].ty
} else {
ty::EarlyBinder::bind(layout.field_tys[*field].ty).instantiate(tcx, self.args)
}
})
})
}
/// This is the types of the fields of a coroutine which are not stored in a
/// variant.
#[inline]
fn prefix_tys(self) -> &'tcx List<Ty<'tcx>> {
self.upvar_tys()
}
}
#[derive(Debug, Copy, Clone, HashStable, TypeFoldable, TypeVisitable)]
pub enum UpvarArgs<'tcx> {
Closure(GenericArgsRef<'tcx>),
Coroutine(GenericArgsRef<'tcx>),
CoroutineClosure(GenericArgsRef<'tcx>),
}
impl<'tcx> UpvarArgs<'tcx> {
/// Returns an iterator over the list of types of captured paths by the closure/coroutine.
/// In case there was a type error in figuring out the types of the captured path, an
/// empty iterator is returned.
#[inline]
pub fn upvar_tys(self) -> &'tcx List<Ty<'tcx>> {
let tupled_tys = match self {
UpvarArgs::Closure(args) => args.as_closure().tupled_upvars_ty(),
UpvarArgs::Coroutine(args) => args.as_coroutine().tupled_upvars_ty(),
UpvarArgs::CoroutineClosure(args) => args.as_coroutine_closure().tupled_upvars_ty(),
};
match tupled_tys.kind() {
TyKind::Error(_) => ty::List::empty(),
TyKind::Tuple(..) => self.tupled_upvars_ty().tuple_fields(),
TyKind::Infer(_) => bug!("upvar_tys called before capture types are inferred"),
ty => bug!("Unexpected representation of upvar types tuple {:?}", ty),
}
}
#[inline]
pub fn tupled_upvars_ty(self) -> Ty<'tcx> {
match self {
UpvarArgs::Closure(args) => args.as_closure().tupled_upvars_ty(),
UpvarArgs::Coroutine(args) => args.as_coroutine().tupled_upvars_ty(),
UpvarArgs::CoroutineClosure(args) => args.as_coroutine_closure().tupled_upvars_ty(),
}
}
}
/// An inline const is modeled like
/// ```ignore (illustrative)
/// const InlineConst<'l0...'li, T0...Tj, R>: R;
/// ```
/// where:
///
/// - 'l0...'li and T0...Tj are the generic parameters
/// inherited from the item that defined the inline const,
/// - R represents the type of the constant.
///
/// When the inline const is instantiated, `R` is instantiated as the actual inferred
/// type of the constant. The reason that `R` is represented as an extra type parameter
/// is the same reason that [`ty::ClosureArgs`] have `CS` and `U` as type parameters:
/// inline const can reference lifetimes that are internal to the creating function.
#[derive(Copy, Clone, Debug)]
pub struct InlineConstArgs<'tcx> {
/// Generic parameters from the enclosing item,
/// concatenated with the inferred type of the constant.
pub args: GenericArgsRef<'tcx>,
}
/// Struct returned by `split()`.
pub struct InlineConstArgsParts<'tcx, T> {
pub parent_args: &'tcx [GenericArg<'tcx>],
pub ty: T,
}
impl<'tcx> InlineConstArgs<'tcx> {
/// Construct `InlineConstArgs` from `InlineConstArgsParts`.
pub fn new(
tcx: TyCtxt<'tcx>,
parts: InlineConstArgsParts<'tcx, Ty<'tcx>>,
) -> InlineConstArgs<'tcx> {
InlineConstArgs {
args: tcx.mk_args_from_iter(
parts.parent_args.iter().copied().chain(std::iter::once(parts.ty.into())),
),
}
}
/// Divides the inline const args into their respective components.
/// The ordering assumed here must match that used by `InlineConstArgs::new` above.
fn split(self) -> InlineConstArgsParts<'tcx, GenericArg<'tcx>> {
match self.args[..] {
[ref parent_args @ .., ty] => InlineConstArgsParts { parent_args, ty },
_ => bug!("inline const args missing synthetics"),
}
}
/// Returns the generic parameters of the inline const's parent.
pub fn parent_args(self) -> &'tcx [GenericArg<'tcx>] {
self.split().parent_args
}
/// Returns the type of this inline const.
pub fn ty(self) -> Ty<'tcx> {
self.split().ty.expect_ty()
}
}
pub type PolyFnSig<'tcx> = Binder<'tcx, FnSig<'tcx>>;
pub type CanonicalPolyFnSig<'tcx> = Canonical<'tcx, Binder<'tcx, FnSig<'tcx>>>;
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, TyDecodable)]
#[derive(HashStable)]
pub struct ParamTy {
pub index: u32,
pub name: Symbol,
}
impl rustc_type_ir::inherent::ParamLike for ParamTy {
fn index(self) -> u32 {
self.index
}
}
impl<'tcx> ParamTy {
pub fn new(index: u32, name: Symbol) -> ParamTy {
ParamTy { index, name }
}
pub fn for_def(def: &ty::GenericParamDef) -> ParamTy {
ParamTy::new(def.index, def.name)
}
#[inline]
pub fn to_ty(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
Ty::new_param(tcx, self.index, self.name)
}
pub fn span_from_generics(self, tcx: TyCtxt<'tcx>, item_with_generics: DefId) -> Span {
let generics = tcx.generics_of(item_with_generics);
let type_param = generics.type_param(self, tcx);
tcx.def_span(type_param.def_id)
}
}
#[derive(Copy, Clone, Hash, TyEncodable, TyDecodable, Eq, PartialEq, Ord, PartialOrd)]
#[derive(HashStable)]
pub struct ParamConst {
pub index: u32,
pub name: Symbol,
}
impl rustc_type_ir::inherent::ParamLike for ParamConst {
fn index(self) -> u32 {
self.index
}
}
impl ParamConst {
pub fn new(index: u32, name: Symbol) -> ParamConst {
ParamConst { index, name }
}
pub fn for_def(def: &ty::GenericParamDef) -> ParamConst {
ParamConst::new(def.index, def.name)
}
#[instrument(level = "debug")]
pub fn find_const_ty_from_env<'tcx>(self, env: ParamEnv<'tcx>) -> Ty<'tcx> {
let mut candidates = env.caller_bounds().iter().filter_map(|clause| {
// `ConstArgHasType` are never desugared to be higher ranked.
match clause.kind().skip_binder() {
ty::ClauseKind::ConstArgHasType(param_ct, ty) => {
assert!(!(param_ct, ty).has_escaping_bound_vars());
match param_ct.kind() {
ty::ConstKind::Param(param_ct) if param_ct.index == self.index => Some(ty),
_ => None,
}
}
_ => None,
}
});
// N.B. it may be tempting to fix ICEs by making this function return
// `Option<Ty<'tcx>>` instead of `Ty<'tcx>`; however, this is generally
// considered to be a bandaid solution, since it hides more important
// underlying issues with how we construct generics and predicates of
// items. It's advised to fix the underlying issue rather than trying
// to modify this function.
let ty = candidates.next().unwrap_or_else(|| {
bug!("cannot find `{self:?}` in param-env: {env:#?}");
});
assert!(
candidates.next().is_none(),
"did not expect duplicate `ConstParamHasTy` for `{self:?}` in param-env: {env:#?}"
);
ty
}
}
/// Constructors for `Ty`
impl<'tcx> Ty<'tcx> {
/// Avoid using this in favour of more specific `new_*` methods, where possible.
/// The more specific methods will often optimize their creation.
#[allow(rustc::usage_of_ty_tykind)]
#[inline]
fn new(tcx: TyCtxt<'tcx>, st: TyKind<'tcx>) -> Ty<'tcx> {
tcx.mk_ty_from_kind(st)
}
#[inline]
pub fn new_infer(tcx: TyCtxt<'tcx>, infer: ty::InferTy) -> Ty<'tcx> {
Ty::new(tcx, TyKind::Infer(infer))
}
#[inline]
pub fn new_var(tcx: TyCtxt<'tcx>, v: ty::TyVid) -> Ty<'tcx> {
// Use a pre-interned one when possible.
tcx.types
.ty_vars
.get(v.as_usize())
.copied()
.unwrap_or_else(|| Ty::new(tcx, Infer(TyVar(v))))
}
#[inline]
pub fn new_int_var(tcx: TyCtxt<'tcx>, v: ty::IntVid) -> Ty<'tcx> {
Ty::new_infer(tcx, IntVar(v))
}
#[inline]
pub fn new_float_var(tcx: TyCtxt<'tcx>, v: ty::FloatVid) -> Ty<'tcx> {
Ty::new_infer(tcx, FloatVar(v))
}
#[inline]
pub fn new_fresh(tcx: TyCtxt<'tcx>, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
tcx.types
.fresh_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| Ty::new_infer(tcx, ty::FreshTy(n)))
}
#[inline]
pub fn new_fresh_int(tcx: TyCtxt<'tcx>, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
tcx.types
.fresh_int_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| Ty::new_infer(tcx, ty::FreshIntTy(n)))
}
#[inline]
pub fn new_fresh_float(tcx: TyCtxt<'tcx>, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
tcx.types
.fresh_float_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| Ty::new_infer(tcx, ty::FreshFloatTy(n)))
}
#[inline]
pub fn new_param(tcx: TyCtxt<'tcx>, index: u32, name: Symbol) -> Ty<'tcx> {
Ty::new(tcx, Param(ParamTy { index, name }))
}
#[inline]
pub fn new_bound(
tcx: TyCtxt<'tcx>,
index: ty::DebruijnIndex,
bound_ty: ty::BoundTy<'tcx>,
) -> Ty<'tcx> {
// Use a pre-interned one when possible.
if let ty::BoundTy { var, kind: ty::BoundTyKind::Anon } = bound_ty
&& let Some(inner) = tcx.types.anon_bound_tys.get(index.as_usize())
&& let Some(ty) = inner.get(var.as_usize()).copied()
{
ty
} else {
Ty::new(tcx, Bound(ty::BoundVarIndexKind::Bound(index), bound_ty))
}
}
#[inline]
pub fn new_canonical_bound(tcx: TyCtxt<'tcx>, var: BoundVar) -> Ty<'tcx> {
// Use a pre-interned one when possible.
if let Some(ty) = tcx.types.anon_canonical_bound_tys.get(var.as_usize()).copied() {
ty
} else {
Ty::new(
tcx,
Bound(
ty::BoundVarIndexKind::Canonical,
ty::BoundTy { var, kind: ty::BoundTyKind::Anon },
),
)
}
}
#[inline]
pub fn new_placeholder(tcx: TyCtxt<'tcx>, placeholder: ty::PlaceholderType<'tcx>) -> Ty<'tcx> {
Ty::new(tcx, Placeholder(placeholder))
}
#[inline]
pub fn new_alias(
tcx: TyCtxt<'tcx>,
kind: ty::AliasTyKind,
alias_ty: ty::AliasTy<'tcx>,
) -> Ty<'tcx> {
debug_assert_matches!(
(kind, tcx.def_kind(alias_ty.def_id)),
(ty::Opaque, DefKind::OpaqueTy)
| (ty::Projection | ty::Inherent, DefKind::AssocTy)
| (ty::Free, DefKind::TyAlias)
);
Ty::new(tcx, Alias(kind, alias_ty))
}
#[inline]
pub fn new_pat(tcx: TyCtxt<'tcx>, base: Ty<'tcx>, pat: ty::Pattern<'tcx>) -> Ty<'tcx> {
Ty::new(tcx, Pat(base, pat))
}
#[inline]
pub fn new_field_representing_type(
tcx: TyCtxt<'tcx>,
base: Ty<'tcx>,
variant: VariantIdx,
field: FieldIdx,
) -> Ty<'tcx> {
let Some(did) = tcx.lang_items().field_representing_type() else {
bug!("could not locate the `FieldRepresentingType` lang item")
};
let def = tcx.adt_def(did);
let args = tcx.mk_args(&[
base.into(),
Const::new_value(
tcx,
ValTree::from_scalar_int(tcx, variant.as_u32().into()),
tcx.types.u32,
)
.into(),
Const::new_value(
tcx,
ValTree::from_scalar_int(tcx, field.as_u32().into()),
tcx.types.u32,
)
.into(),
]);
Ty::new_adt(tcx, def, args)
}
#[inline]
#[instrument(level = "debug", skip(tcx))]
pub fn new_opaque(tcx: TyCtxt<'tcx>, def_id: DefId, args: GenericArgsRef<'tcx>) -> Ty<'tcx> {
Ty::new_alias(tcx, ty::Opaque, AliasTy::new_from_args(tcx, def_id, args))
}
/// Constructs a `TyKind::Error` type with current `ErrorGuaranteed`
pub fn new_error(tcx: TyCtxt<'tcx>, guar: ErrorGuaranteed) -> Ty<'tcx> {
Ty::new(tcx, Error(guar))
}
/// Constructs a `TyKind::Error` type and registers a `span_delayed_bug` to ensure it gets used.
#[track_caller]
pub fn new_misc_error(tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
Ty::new_error_with_message(tcx, DUMMY_SP, "TyKind::Error constructed but no error reported")
}
/// Constructs a `TyKind::Error` type and registers a `span_delayed_bug` with the given `msg` to
/// ensure it gets used.
#[track_caller]
pub fn new_error_with_message<S: Into<MultiSpan>>(
tcx: TyCtxt<'tcx>,
span: S,
msg: impl Into<Cow<'static, str>>,
) -> Ty<'tcx> {
let reported = tcx.dcx().span_delayed_bug(span, msg);
Ty::new(tcx, Error(reported))
}
#[inline]
pub fn new_int(tcx: TyCtxt<'tcx>, i: ty::IntTy) -> Ty<'tcx> {
use ty::IntTy::*;
match i {
Isize => tcx.types.isize,
I8 => tcx.types.i8,
I16 => tcx.types.i16,
I32 => tcx.types.i32,
I64 => tcx.types.i64,
I128 => tcx.types.i128,
}
}
#[inline]
pub fn new_uint(tcx: TyCtxt<'tcx>, ui: ty::UintTy) -> Ty<'tcx> {
use ty::UintTy::*;
match ui {
Usize => tcx.types.usize,
U8 => tcx.types.u8,
U16 => tcx.types.u16,
U32 => tcx.types.u32,
U64 => tcx.types.u64,
U128 => tcx.types.u128,
}
}
#[inline]
pub fn new_float(tcx: TyCtxt<'tcx>, f: ty::FloatTy) -> Ty<'tcx> {
use ty::FloatTy::*;
match f {
F16 => tcx.types.f16,
F32 => tcx.types.f32,
F64 => tcx.types.f64,
F128 => tcx.types.f128,
}
}
#[inline]
pub fn new_ref(
tcx: TyCtxt<'tcx>,
r: Region<'tcx>,
ty: Ty<'tcx>,
mutbl: ty::Mutability,
) -> Ty<'tcx> {
Ty::new(tcx, Ref(r, ty, mutbl))
}
#[inline]
pub fn new_mut_ref(tcx: TyCtxt<'tcx>, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
Ty::new_ref(tcx, r, ty, hir::Mutability::Mut)
}
#[inline]
pub fn new_imm_ref(tcx: TyCtxt<'tcx>, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
Ty::new_ref(tcx, r, ty, hir::Mutability::Not)
}
pub fn new_pinned_ref(
tcx: TyCtxt<'tcx>,
r: Region<'tcx>,
ty: Ty<'tcx>,
mutbl: ty::Mutability,
) -> Ty<'tcx> {
let pin = tcx.adt_def(tcx.require_lang_item(LangItem::Pin, DUMMY_SP));
Ty::new_adt(tcx, pin, tcx.mk_args(&[Ty::new_ref(tcx, r, ty, mutbl).into()]))
}
#[inline]
pub fn new_ptr(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, mutbl: ty::Mutability) -> Ty<'tcx> {
Ty::new(tcx, ty::RawPtr(ty, mutbl))
}
#[inline]
pub fn new_mut_ptr(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
Ty::new_ptr(tcx, ty, hir::Mutability::Mut)
}
#[inline]
pub fn new_imm_ptr(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
Ty::new_ptr(tcx, ty, hir::Mutability::Not)
}
#[inline]
pub fn new_adt(tcx: TyCtxt<'tcx>, def: AdtDef<'tcx>, args: GenericArgsRef<'tcx>) -> Ty<'tcx> {
tcx.debug_assert_args_compatible(def.did(), args);
if cfg!(debug_assertions) {
match tcx.def_kind(def.did()) {
DefKind::Struct | DefKind::Union | DefKind::Enum => {}
DefKind::Mod
| DefKind::Variant
| DefKind::Trait
| DefKind::TyAlias
| DefKind::ForeignTy
| DefKind::TraitAlias
| DefKind::AssocTy
| DefKind::TyParam
| DefKind::Fn
| DefKind::Const { .. }
| DefKind::ConstParam
| DefKind::Static { .. }
| DefKind::Ctor(..)
| DefKind::AssocFn
| DefKind::AssocConst { .. }
| DefKind::Macro(..)
| DefKind::ExternCrate
| DefKind::Use
| DefKind::ForeignMod
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::OpaqueTy
| DefKind::Field
| DefKind::LifetimeParam
| DefKind::GlobalAsm
| DefKind::Impl { .. }
| DefKind::Closure
| DefKind::SyntheticCoroutineBody => {
bug!("not an adt: {def:?} ({:?})", tcx.def_kind(def.did()))
}
}
}
Ty::new(tcx, Adt(def, args))
}
#[inline]
pub fn new_foreign(tcx: TyCtxt<'tcx>, def_id: DefId) -> Ty<'tcx> {
Ty::new(tcx, Foreign(def_id))
}
#[inline]
pub fn new_array(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, n: u64) -> Ty<'tcx> {
Ty::new(tcx, Array(ty, ty::Const::from_target_usize(tcx, n)))
}
#[inline]
pub fn new_array_with_const_len(
tcx: TyCtxt<'tcx>,
ty: Ty<'tcx>,
ct: ty::Const<'tcx>,
) -> Ty<'tcx> {
Ty::new(tcx, Array(ty, ct))
}
#[inline]
pub fn new_slice(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
Ty::new(tcx, Slice(ty))
}
#[inline]
pub fn new_tup(tcx: TyCtxt<'tcx>, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
if ts.is_empty() { tcx.types.unit } else { Ty::new(tcx, Tuple(tcx.mk_type_list(ts))) }
}
pub fn new_tup_from_iter<I, T>(tcx: TyCtxt<'tcx>, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, Ty<'tcx>>,
{
T::collect_and_apply(iter, |ts| Ty::new_tup(tcx, ts))
}
#[inline]
pub fn new_fn_def(
tcx: TyCtxt<'tcx>,
def_id: DefId,
args: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> Ty<'tcx> {
debug_assert_matches!(
tcx.def_kind(def_id),
DefKind::AssocFn | DefKind::Fn | DefKind::Ctor(_, CtorKind::Fn)
);
let args = tcx.check_and_mk_args(def_id, args);
Ty::new(tcx, FnDef(def_id, args))
}
#[inline]
pub fn new_fn_ptr(tcx: TyCtxt<'tcx>, fty: PolyFnSig<'tcx>) -> Ty<'tcx> {
let (sig_tys, hdr) = fty.split();
Ty::new(tcx, FnPtr(sig_tys, hdr))
}
#[inline]
pub fn new_unsafe_binder(tcx: TyCtxt<'tcx>, b: Binder<'tcx, Ty<'tcx>>) -> Ty<'tcx> {
Ty::new(tcx, UnsafeBinder(b.into()))
}
#[inline]
pub fn new_dynamic(
tcx: TyCtxt<'tcx>,
obj: &'tcx List<ty::PolyExistentialPredicate<'tcx>>,
reg: ty::Region<'tcx>,
) -> Ty<'tcx> {
if cfg!(debug_assertions) {
let projection_count = obj
.projection_bounds()
.filter(|item| !tcx.generics_require_sized_self(item.item_def_id()))
.count();
let expected_count: usize = obj
.principal_def_id()
.into_iter()
.flat_map(|principal_def_id| {
// IMPORTANT: This has to agree with HIR ty lowering of dyn trait!
elaborate::supertraits(
tcx,
ty::Binder::dummy(ty::TraitRef::identity(tcx, principal_def_id)),
)
.map(|principal| {
tcx.associated_items(principal.def_id())
.in_definition_order()
.filter(|item| item.is_type() || item.is_type_const())
.filter(|item| !item.is_impl_trait_in_trait())
.filter(|item| !tcx.generics_require_sized_self(item.def_id))
.count()
})
})
.sum();
assert_eq!(
projection_count, expected_count,
"expected {obj:?} to have {expected_count} projections, \
but it has {projection_count}"
);
}
Ty::new(tcx, Dynamic(obj, reg))
}
#[inline]
pub fn new_projection_from_args(
tcx: TyCtxt<'tcx>,
item_def_id: DefId,
args: ty::GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
Ty::new_alias(tcx, ty::Projection, AliasTy::new_from_args(tcx, item_def_id, args))
}
#[inline]
pub fn new_projection(
tcx: TyCtxt<'tcx>,
item_def_id: DefId,
args: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> Ty<'tcx> {
Ty::new_alias(tcx, ty::Projection, AliasTy::new(tcx, item_def_id, args))
}
#[inline]
pub fn new_closure(
tcx: TyCtxt<'tcx>,
def_id: DefId,
closure_args: GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
tcx.debug_assert_args_compatible(def_id, closure_args);
Ty::new(tcx, Closure(def_id, closure_args))
}
#[inline]
pub fn new_coroutine_closure(
tcx: TyCtxt<'tcx>,
def_id: DefId,
closure_args: GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
tcx.debug_assert_args_compatible(def_id, closure_args);
Ty::new(tcx, CoroutineClosure(def_id, closure_args))
}
#[inline]
pub fn new_coroutine(
tcx: TyCtxt<'tcx>,
def_id: DefId,
coroutine_args: GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
tcx.debug_assert_args_compatible(def_id, coroutine_args);
Ty::new(tcx, Coroutine(def_id, coroutine_args))
}
#[inline]
pub fn new_coroutine_witness(
tcx: TyCtxt<'tcx>,
def_id: DefId,
args: GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
if cfg!(debug_assertions) {
tcx.debug_assert_args_compatible(tcx.typeck_root_def_id(def_id), args);
}
Ty::new(tcx, CoroutineWitness(def_id, args))
}
pub fn new_coroutine_witness_for_coroutine(
tcx: TyCtxt<'tcx>,
def_id: DefId,
coroutine_args: GenericArgsRef<'tcx>,
) -> Ty<'tcx> {
tcx.debug_assert_args_compatible(def_id, coroutine_args);
// HACK: Coroutine witness types are lifetime erased, so they
// never reference any lifetime args from the coroutine. We erase
// the regions here since we may get into situations where a
// coroutine is recursively contained within itself, leading to
// witness types that differ by region args. This means that
// cycle detection in fulfillment will not kick in, which leads
// to unnecessary overflows in async code. See the issue:
// <https://github.com/rust-lang/rust/issues/145151>.
let args =
ty::GenericArgs::for_item(tcx, tcx.typeck_root_def_id(def_id), |def, _| {
match def.kind {
ty::GenericParamDefKind::Lifetime => tcx.lifetimes.re_erased.into(),
ty::GenericParamDefKind::Type { .. }
| ty::GenericParamDefKind::Const { .. } => coroutine_args[def.index as usize],
}
});
Ty::new_coroutine_witness(tcx, def_id, args)
}
// misc
#[inline]
pub fn new_static_str(tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
Ty::new_imm_ref(tcx, tcx.lifetimes.re_static, tcx.types.str_)
}
// lang and diagnostic tys
fn new_generic_adt(tcx: TyCtxt<'tcx>, wrapper_def_id: DefId, ty_param: Ty<'tcx>) -> Ty<'tcx> {
let adt_def = tcx.adt_def(wrapper_def_id);
let args = GenericArgs::for_item(tcx, wrapper_def_id, |param, args| match param.kind {
GenericParamDefKind::Lifetime | GenericParamDefKind::Const { .. } => bug!(),
GenericParamDefKind::Type { has_default, .. } => {
if param.index == 0 {
ty_param.into()
} else {
assert!(has_default);
tcx.type_of(param.def_id).instantiate(tcx, args).into()
}
}
});
Ty::new_adt(tcx, adt_def, args)
}
#[inline]
pub fn new_lang_item(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, item: LangItem) -> Option<Ty<'tcx>> {
let def_id = tcx.lang_items().get(item)?;
Some(Ty::new_generic_adt(tcx, def_id, ty))
}
#[inline]
pub fn new_diagnostic_item(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, name: Symbol) -> Option<Ty<'tcx>> {
let def_id = tcx.get_diagnostic_item(name)?;
Some(Ty::new_generic_adt(tcx, def_id, ty))
}
#[inline]
pub fn new_box(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
let def_id = tcx.require_lang_item(LangItem::OwnedBox, DUMMY_SP);
Ty::new_generic_adt(tcx, def_id, ty)
}
#[inline]
pub fn new_option(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
let def_id = tcx.require_lang_item(LangItem::Option, DUMMY_SP);
Ty::new_generic_adt(tcx, def_id, ty)
}
#[inline]
pub fn new_maybe_uninit(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
let def_id = tcx.require_lang_item(LangItem::MaybeUninit, DUMMY_SP);
Ty::new_generic_adt(tcx, def_id, ty)
}
/// Creates a `&mut Context<'_>` [`Ty`] with erased lifetimes.
pub fn new_task_context(tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
let context_did = tcx.require_lang_item(LangItem::Context, DUMMY_SP);
let context_adt_ref = tcx.adt_def(context_did);
let context_args = tcx.mk_args(&[tcx.lifetimes.re_erased.into()]);
let context_ty = Ty::new_adt(tcx, context_adt_ref, context_args);
Ty::new_mut_ref(tcx, tcx.lifetimes.re_erased, context_ty)
}
}
impl<'tcx> rustc_type_ir::inherent::Ty<TyCtxt<'tcx>> for Ty<'tcx> {
fn new_bool(tcx: TyCtxt<'tcx>) -> Self {
tcx.types.bool
}
fn new_u8(tcx: TyCtxt<'tcx>) -> Self {
tcx.types.u8
}
fn new_infer(tcx: TyCtxt<'tcx>, infer: ty::InferTy) -> Self {
Ty::new_infer(tcx, infer)
}
fn new_var(tcx: TyCtxt<'tcx>, vid: ty::TyVid) -> Self {
Ty::new_var(tcx, vid)
}
fn new_param(tcx: TyCtxt<'tcx>, param: ty::ParamTy) -> Self {
Ty::new_param(tcx, param.index, param.name)
}
fn new_placeholder(tcx: TyCtxt<'tcx>, placeholder: ty::PlaceholderType<'tcx>) -> Self {
Ty::new_placeholder(tcx, placeholder)
}
fn new_bound(
interner: TyCtxt<'tcx>,
debruijn: ty::DebruijnIndex,
var: ty::BoundTy<'tcx>,
) -> Self {
Ty::new_bound(interner, debruijn, var)
}
fn new_anon_bound(tcx: TyCtxt<'tcx>, debruijn: ty::DebruijnIndex, var: ty::BoundVar) -> Self {
Ty::new_bound(tcx, debruijn, ty::BoundTy { var, kind: ty::BoundTyKind::Anon })
}
fn new_canonical_bound(tcx: TyCtxt<'tcx>, var: ty::BoundVar) -> Self {
Ty::new_canonical_bound(tcx, var)
}
fn new_alias(
interner: TyCtxt<'tcx>,
kind: ty::AliasTyKind,
alias_ty: ty::AliasTy<'tcx>,
) -> Self {
Ty::new_alias(interner, kind, alias_ty)
}
fn new_error(interner: TyCtxt<'tcx>, guar: ErrorGuaranteed) -> Self {
Ty::new_error(interner, guar)
}
fn new_adt(
interner: TyCtxt<'tcx>,
adt_def: ty::AdtDef<'tcx>,
args: ty::GenericArgsRef<'tcx>,
) -> Self {
Ty::new_adt(interner, adt_def, args)
}
fn new_foreign(interner: TyCtxt<'tcx>, def_id: DefId) -> Self {
Ty::new_foreign(interner, def_id)
}
fn new_dynamic(
interner: TyCtxt<'tcx>,
preds: &'tcx List<ty::PolyExistentialPredicate<'tcx>>,
region: ty::Region<'tcx>,
) -> Self {
Ty::new_dynamic(interner, preds, region)
}
fn new_coroutine(
interner: TyCtxt<'tcx>,
def_id: DefId,
args: ty::GenericArgsRef<'tcx>,
) -> Self {
Ty::new_coroutine(interner, def_id, args)
}
fn new_coroutine_closure(
interner: TyCtxt<'tcx>,
def_id: DefId,
args: ty::GenericArgsRef<'tcx>,
) -> Self {
Ty::new_coroutine_closure(interner, def_id, args)
}
fn new_closure(interner: TyCtxt<'tcx>, def_id: DefId, args: ty::GenericArgsRef<'tcx>) -> Self {
Ty::new_closure(interner, def_id, args)
}
fn new_coroutine_witness(
interner: TyCtxt<'tcx>,
def_id: DefId,
args: ty::GenericArgsRef<'tcx>,
) -> Self {
Ty::new_coroutine_witness(interner, def_id, args)
}
fn new_coroutine_witness_for_coroutine(
interner: TyCtxt<'tcx>,
def_id: DefId,
coroutine_args: ty::GenericArgsRef<'tcx>,
) -> Self {
Ty::new_coroutine_witness_for_coroutine(interner, def_id, coroutine_args)
}
fn new_ptr(interner: TyCtxt<'tcx>, ty: Self, mutbl: hir::Mutability) -> Self {
Ty::new_ptr(interner, ty, mutbl)
}
fn new_ref(
interner: TyCtxt<'tcx>,
region: ty::Region<'tcx>,
ty: Self,
mutbl: hir::Mutability,
) -> Self {
Ty::new_ref(interner, region, ty, mutbl)
}
fn new_array_with_const_len(interner: TyCtxt<'tcx>, ty: Self, len: ty::Const<'tcx>) -> Self {
Ty::new_array_with_const_len(interner, ty, len)
}
fn new_slice(interner: TyCtxt<'tcx>, ty: Self) -> Self {
Ty::new_slice(interner, ty)
}
fn new_tup(interner: TyCtxt<'tcx>, tys: &[Ty<'tcx>]) -> Self {
Ty::new_tup(interner, tys)
}
fn new_tup_from_iter<It, T>(interner: TyCtxt<'tcx>, iter: It) -> T::Output
where
It: Iterator<Item = T>,
T: CollectAndApply<Self, Self>,
{
Ty::new_tup_from_iter(interner, iter)
}
fn tuple_fields(self) -> &'tcx ty::List<Ty<'tcx>> {
self.tuple_fields()
}
fn to_opt_closure_kind(self) -> Option<ty::ClosureKind> {
self.to_opt_closure_kind()
}
fn from_closure_kind(interner: TyCtxt<'tcx>, kind: ty::ClosureKind) -> Self {
Ty::from_closure_kind(interner, kind)
}
fn from_coroutine_closure_kind(
interner: TyCtxt<'tcx>,
kind: rustc_type_ir::ClosureKind,
) -> Self {
Ty::from_coroutine_closure_kind(interner, kind)
}
fn new_fn_def(interner: TyCtxt<'tcx>, def_id: DefId, args: ty::GenericArgsRef<'tcx>) -> Self {
Ty::new_fn_def(interner, def_id, args)
}
fn new_fn_ptr(interner: TyCtxt<'tcx>, sig: ty::Binder<'tcx, ty::FnSig<'tcx>>) -> Self {
Ty::new_fn_ptr(interner, sig)
}
fn new_pat(interner: TyCtxt<'tcx>, ty: Self, pat: ty::Pattern<'tcx>) -> Self {
Ty::new_pat(interner, ty, pat)
}
fn new_unsafe_binder(interner: TyCtxt<'tcx>, ty: ty::Binder<'tcx, Ty<'tcx>>) -> Self {
Ty::new_unsafe_binder(interner, ty)
}
fn new_unit(interner: TyCtxt<'tcx>) -> Self {
interner.types.unit
}
fn new_usize(interner: TyCtxt<'tcx>) -> Self {
interner.types.usize
}
fn discriminant_ty(self, interner: TyCtxt<'tcx>) -> Ty<'tcx> {
self.discriminant_ty(interner)
}
fn has_unsafe_fields(self) -> bool {
Ty::has_unsafe_fields(self)
}
}
/// Type utilities
impl<'tcx> Ty<'tcx> {
// It would be nicer if this returned the value instead of a reference,
// like how `Predicate::kind` and `Region::kind` do. (It would result in
// many fewer subsequent dereferences.) But that gives a small but
// noticeable performance hit. See #126069 for details.
#[inline(always)]
pub fn kind(self) -> &'tcx TyKind<'tcx> {
self.0.0
}
// FIXME(compiler-errors): Think about removing this.
#[inline(always)]
pub fn flags(self) -> TypeFlags {
self.0.0.flags
}
#[inline]
pub fn is_unit(self) -> bool {
match self.kind() {
Tuple(tys) => tys.is_empty(),
_ => false,
}
}
/// Check if type is an `usize`.
#[inline]
pub fn is_usize(self) -> bool {
matches!(self.kind(), Uint(UintTy::Usize))
}
/// Check if type is an `usize` or an integral type variable.
#[inline]
pub fn is_usize_like(self) -> bool {
matches!(self.kind(), Uint(UintTy::Usize) | Infer(IntVar(_)))
}
#[inline]
pub fn is_never(self) -> bool {
matches!(self.kind(), Never)
}
#[inline]
pub fn is_primitive(self) -> bool {
matches!(self.kind(), Bool | Char | Int(_) | Uint(_) | Float(_))
}
#[inline]
pub fn is_adt(self) -> bool {
matches!(self.kind(), Adt(..))
}
#[inline]
pub fn is_ref(self) -> bool {
matches!(self.kind(), Ref(..))
}
#[inline]
pub fn is_ty_var(self) -> bool {
matches!(self.kind(), Infer(TyVar(_)))
}
#[inline]
pub fn ty_vid(self) -> Option<ty::TyVid> {
match self.kind() {
&Infer(TyVar(vid)) => Some(vid),
_ => None,
}
}
#[inline]
pub fn is_ty_or_numeric_infer(self) -> bool {
matches!(self.kind(), Infer(_))
}
#[inline]
pub fn is_phantom_data(self) -> bool {
if let Adt(def, _) = self.kind() { def.is_phantom_data() } else { false }
}
#[inline]
pub fn is_bool(self) -> bool {
*self.kind() == Bool
}
/// Returns `true` if this type is a `str`.
#[inline]
pub fn is_str(self) -> bool {
*self.kind() == Str
}
/// Returns true if this type is `&str`. The reference's lifetime is ignored.
#[inline]
pub fn is_imm_ref_str(self) -> bool {
matches!(self.kind(), ty::Ref(_, inner, hir::Mutability::Not) if inner.is_str())
}
#[inline]
pub fn is_param(self, index: u32) -> bool {
match self.kind() {
ty::Param(data) => data.index == index,
_ => false,
}
}
#[inline]
pub fn is_slice(self) -> bool {
matches!(self.kind(), Slice(_))
}
#[inline]
pub fn is_array_slice(self) -> bool {
match self.kind() {
Slice(_) => true,
ty::RawPtr(ty, _) | Ref(_, ty, _) => matches!(ty.kind(), Slice(_)),
_ => false,
}
}
#[inline]
pub fn is_array(self) -> bool {
matches!(self.kind(), Array(..))
}
#[inline]
pub fn is_simd(self) -> bool {
match self.kind() {
Adt(def, _) => def.repr().simd(),
_ => false,
}
}
#[inline]
pub fn is_scalable_vector(self) -> bool {
match self.kind() {
Adt(def, _) => def.repr().scalable(),
_ => false,
}
}
pub fn sequence_element_type(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
match self.kind() {
Array(ty, _) | Slice(ty) => *ty,
Str => tcx.types.u8,
_ => bug!("`sequence_element_type` called on non-sequence value: {}", self),
}
}
pub fn scalable_vector_element_count_and_type(self, tcx: TyCtxt<'tcx>) -> (u16, Ty<'tcx>) {
let Adt(def, args) = self.kind() else {
bug!("`scalable_vector_size_and_type` called on invalid type")
};
let Some(ScalableElt::ElementCount(element_count)) = def.repr().scalable else {
bug!("`scalable_vector_size_and_type` called on non-scalable vector type");
};
let variant = def.non_enum_variant();
assert_eq!(variant.fields.len(), 1);
let field_ty = variant.fields[FieldIdx::ZERO].ty(tcx, args);
(element_count, field_ty)
}
pub fn simd_size_and_type(self, tcx: TyCtxt<'tcx>) -> (u64, Ty<'tcx>) {
let Adt(def, args) = self.kind() else {
bug!("`simd_size_and_type` called on invalid type")
};
assert!(def.repr().simd(), "`simd_size_and_type` called on non-SIMD type");
let variant = def.non_enum_variant();
assert_eq!(variant.fields.len(), 1);
let field_ty = variant.fields[FieldIdx::ZERO].ty(tcx, args);
let Array(f0_elem_ty, f0_len) = field_ty.kind() else {
bug!("Simd type has non-array field type {field_ty:?}")
};
// FIXME(repr_simd): https://github.com/rust-lang/rust/pull/78863#discussion_r522784112
// The way we evaluate the `N` in `[T; N]` here only works since we use
// `simd_size_and_type` post-monomorphization. It will probably start to ICE
// if we use it in generic code. See the `simd-array-trait` ui test.
(
f0_len
.try_to_target_usize(tcx)
.expect("expected SIMD field to have definite array size"),
*f0_elem_ty,
)
}
#[inline]
pub fn is_mutable_ptr(self) -> bool {
matches!(self.kind(), RawPtr(_, hir::Mutability::Mut) | Ref(_, _, hir::Mutability::Mut))
}
/// Get the mutability of the reference or `None` when not a reference
#[inline]
pub fn ref_mutability(self) -> Option<hir::Mutability> {
match self.kind() {
Ref(_, _, mutability) => Some(*mutability),
_ => None,
}
}
#[inline]
pub fn is_raw_ptr(self) -> bool {
matches!(self.kind(), RawPtr(_, _))
}
/// Tests if this is any kind of primitive pointer type (reference, raw pointer, fn pointer).
/// `Box` is *not* considered a pointer here!
#[inline]
pub fn is_any_ptr(self) -> bool {
self.is_ref() || self.is_raw_ptr() || self.is_fn_ptr()
}
#[inline]
pub fn is_box(self) -> bool {
match self.kind() {
Adt(def, _) => def.is_box(),
_ => false,
}
}
/// Tests whether this is a Box definitely using the global allocator.
///
/// If the allocator is still generic, the answer is `false`, but it may
/// later turn out that it does use the global allocator.
#[inline]
pub fn is_box_global(self, tcx: TyCtxt<'tcx>) -> bool {
match self.kind() {
Adt(def, args) if def.is_box() => {
let Some(alloc) = args.get(1) else {
// Single-argument Box is always global. (for "minicore" tests)
return true;
};
alloc.expect_ty().ty_adt_def().is_some_and(|alloc_adt| {
tcx.is_lang_item(alloc_adt.did(), LangItem::GlobalAlloc)
})
}
_ => false,
}
}
pub fn boxed_ty(self) -> Option<Ty<'tcx>> {
match self.kind() {
Adt(def, args) if def.is_box() => Some(args.type_at(0)),
_ => None,
}
}
pub fn pinned_ty(self) -> Option<Ty<'tcx>> {
match self.kind() {
Adt(def, args) if def.is_pin() => Some(args.type_at(0)),
_ => None,
}
}
/// Returns the type, pinnedness, mutability, and the region of a reference (`&T` or `&mut T`)
/// or a pinned-reference type (`Pin<&T>` or `Pin<&mut T>`).
///
/// Regarding the [`pin_ergonomics`] feature, one of the goals is to make pinned references
/// (`Pin<&T>` and `Pin<&mut T>`) behaves similar to normal references (`&T` and `&mut T`).
/// This function is useful when references and pinned references are processed similarly.
///
/// [`pin_ergonomics`]: https://github.com/rust-lang/rust/issues/130494
pub fn maybe_pinned_ref(
self,
) -> Option<(Ty<'tcx>, ty::Pinnedness, ty::Mutability, Region<'tcx>)> {
match self.kind() {
Adt(def, args)
if def.is_pin()
&& let &ty::Ref(region, ty, mutbl) = args.type_at(0).kind() =>
{
Some((ty, ty::Pinnedness::Pinned, mutbl, region))
}
&Ref(region, ty, mutbl) => Some((ty, ty::Pinnedness::Not, mutbl, region)),
_ => None,
}
}
/// Panics if called on any type other than `Box<T>`.
pub fn expect_boxed_ty(self) -> Ty<'tcx> {
self.boxed_ty()
.unwrap_or_else(|| bug!("`expect_boxed_ty` is called on non-box type {:?}", self))
}
/// A scalar type is one that denotes an atomic datum, with no sub-components.
/// (A RawPtr is scalar because it represents a non-managed pointer, so its
/// contents are abstract to rustc.)
#[inline]
pub fn is_scalar(self) -> bool {
matches!(
self.kind(),
Bool | Char
| Int(_)
| Float(_)
| Uint(_)
| FnDef(..)
| FnPtr(..)
| RawPtr(_, _)
| Infer(IntVar(_) | FloatVar(_))
)
}
/// Returns `true` if this type is a floating point type.
#[inline]
pub fn is_floating_point(self) -> bool {
matches!(self.kind(), Float(_) | Infer(FloatVar(_)))
}
#[inline]
pub fn is_trait(self) -> bool {
matches!(self.kind(), Dynamic(_, _))
}
#[inline]
pub fn is_enum(self) -> bool {
matches!(self.kind(), Adt(adt_def, _) if adt_def.is_enum())
}
#[inline]
pub fn is_union(self) -> bool {
matches!(self.kind(), Adt(adt_def, _) if adt_def.is_union())
}
#[inline]
pub fn is_closure(self) -> bool {
matches!(self.kind(), Closure(..))
}
#[inline]
pub fn is_coroutine(self) -> bool {
matches!(self.kind(), Coroutine(..))
}
#[inline]
pub fn is_coroutine_closure(self) -> bool {
matches!(self.kind(), CoroutineClosure(..))
}
#[inline]
pub fn is_integral(self) -> bool {
matches!(self.kind(), Infer(IntVar(_)) | Int(_) | Uint(_))
}
#[inline]
pub fn is_fresh_ty(self) -> bool {
matches!(self.kind(), Infer(FreshTy(_)))
}
#[inline]
pub fn is_fresh(self) -> bool {
matches!(self.kind(), Infer(FreshTy(_) | FreshIntTy(_) | FreshFloatTy(_)))
}
#[inline]
pub fn is_char(self) -> bool {
matches!(self.kind(), Char)
}
#[inline]
pub fn is_numeric(self) -> bool {
self.is_integral() || self.is_floating_point()
}
#[inline]
pub fn is_signed(self) -> bool {
matches!(self.kind(), Int(_))
}
#[inline]
pub fn is_ptr_sized_integral(self) -> bool {
matches!(self.kind(), Int(ty::IntTy::Isize) | Uint(ty::UintTy::Usize))
}
#[inline]
pub fn has_concrete_skeleton(self) -> bool {
!matches!(self.kind(), Param(_) | Infer(_) | Error(_))
}
/// Checks whether a type recursively contains another type
///
/// Example: `Option<()>` contains `()`
pub fn contains(self, other: Ty<'tcx>) -> bool {
struct ContainsTyVisitor<'tcx>(Ty<'tcx>);
impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for ContainsTyVisitor<'tcx> {
type Result = ControlFlow<()>;
fn visit_ty(&mut self, t: Ty<'tcx>) -> Self::Result {
if self.0 == t { ControlFlow::Break(()) } else { t.super_visit_with(self) }
}
}
let cf = self.visit_with(&mut ContainsTyVisitor(other));
cf.is_break()
}
/// Checks whether a type recursively contains any closure
///
/// Example: `Option<{closure@file.rs:4:20}>` returns true
pub fn contains_closure(self) -> bool {
struct ContainsClosureVisitor;
impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for ContainsClosureVisitor {
type Result = ControlFlow<()>;
fn visit_ty(&mut self, t: Ty<'tcx>) -> Self::Result {
if let ty::Closure(..) = t.kind() {
ControlFlow::Break(())
} else {
t.super_visit_with(self)
}
}
}
let cf = self.visit_with(&mut ContainsClosureVisitor);
cf.is_break()
}
/// Returns the deepest `async_drop_in_place::{closure}` implementation.
///
/// `async_drop_in_place<T>::{closure}`, when T is a coroutine, is a proxy-impl
/// to call async drop poll from impl coroutine.
pub fn find_async_drop_impl_coroutine<F: FnMut(Ty<'tcx>)>(
self,
tcx: TyCtxt<'tcx>,
mut f: F,
) -> Ty<'tcx> {
assert!(self.is_coroutine());
let mut cor_ty = self;
let mut ty = cor_ty;
loop {
let ty::Coroutine(def_id, args) = ty.kind() else { return cor_ty };
cor_ty = ty;
f(ty);
if !tcx.is_async_drop_in_place_coroutine(*def_id) {
return cor_ty;
}
ty = args.first().unwrap().expect_ty();
}
}
/// Returns the type of `*ty`.
///
/// The parameter `explicit` indicates if this is an *explicit* dereference.
/// Some types -- notably raw ptrs -- can only be dereferenced explicitly.
pub fn builtin_deref(self, explicit: bool) -> Option<Ty<'tcx>> {
match *self.kind() {
_ if let Some(boxed) = self.boxed_ty() => Some(boxed),
Ref(_, ty, _) => Some(ty),
RawPtr(ty, _) if explicit => Some(ty),
_ => None,
}
}
/// Returns the type of `ty[i]`.
pub fn builtin_index(self) -> Option<Ty<'tcx>> {
match self.kind() {
Array(ty, _) | Slice(ty) => Some(*ty),
_ => None,
}
}
#[tracing::instrument(level = "trace", skip(tcx))]
pub fn fn_sig(self, tcx: TyCtxt<'tcx>) -> PolyFnSig<'tcx> {
self.kind().fn_sig(tcx)
}
#[inline]
pub fn is_fn(self) -> bool {
matches!(self.kind(), FnDef(..) | FnPtr(..))
}
#[inline]
pub fn is_fn_ptr(self) -> bool {
matches!(self.kind(), FnPtr(..))
}
#[inline]
pub fn is_impl_trait(self) -> bool {
matches!(self.kind(), Alias(ty::Opaque, ..))
}
#[inline]
pub fn ty_adt_def(self) -> Option<AdtDef<'tcx>> {
match self.kind() {
Adt(adt, _) => Some(*adt),
_ => None,
}
}
/// Returns a list of tuple type arguments.
///
/// Panics when called on anything but a tuple.
#[inline]
pub fn tuple_fields(self) -> &'tcx List<Ty<'tcx>> {
match self.kind() {
Tuple(args) => args,
_ => bug!("tuple_fields called on non-tuple: {self:?}"),
}
}
/// Returns a list of tuple type arguments, or `None` if `self` isn't a tuple.
#[inline]
pub fn opt_tuple_fields(self) -> Option<&'tcx List<Ty<'tcx>>> {
match self.kind() {
Tuple(args) => Some(args),
_ => None,
}
}
/// If the type contains variants, returns the valid range of variant indices.
//
// FIXME: This requires the optimized MIR in the case of coroutines.
#[inline]
pub fn variant_range(self, tcx: TyCtxt<'tcx>) -> Option<Range<VariantIdx>> {
match self.kind() {
TyKind::Adt(adt, _) => Some(adt.variant_range()),
TyKind::Coroutine(def_id, args) => {
Some(args.as_coroutine().variant_range(*def_id, tcx))
}
_ => None,
}
}
/// If the type contains variants, returns the variant for `variant_index`.
/// Panics if `variant_index` is out of range.
//
// FIXME: This requires the optimized MIR in the case of coroutines.
#[inline]
pub fn discriminant_for_variant(
self,
tcx: TyCtxt<'tcx>,
variant_index: VariantIdx,
) -> Option<Discr<'tcx>> {
match self.kind() {
TyKind::Adt(adt, _) if adt.is_enum() => {
Some(adt.discriminant_for_variant(tcx, variant_index))
}
TyKind::Coroutine(def_id, args) => {
Some(args.as_coroutine().discriminant_for_variant(*def_id, tcx, variant_index))
}
_ => None,
}
}
/// Returns the type of the discriminant of this type.
pub fn discriminant_ty(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
match self.kind() {
ty::Adt(adt, _) if adt.is_enum() => adt.repr().discr_type().to_ty(tcx),
ty::Coroutine(_, args) => args.as_coroutine().discr_ty(tcx),
ty::Param(_) | ty::Alias(..) | ty::Infer(ty::TyVar(_)) => {
let assoc_items = tcx.associated_item_def_ids(
tcx.require_lang_item(hir::LangItem::DiscriminantKind, DUMMY_SP),
);
Ty::new_projection_from_args(tcx, assoc_items[0], tcx.mk_args(&[self.into()]))
}
ty::Pat(ty, _) => ty.discriminant_ty(tcx),
ty::Bool
| ty::Char
| ty::Int(_)
| ty::Uint(_)
| ty::Float(_)
| ty::Adt(..)
| ty::Foreign(_)
| ty::Str
| ty::Array(..)
| ty::Slice(_)
| ty::RawPtr(_, _)
| ty::Ref(..)
| ty::FnDef(..)
| ty::FnPtr(..)
| ty::Dynamic(..)
| ty::Closure(..)
| ty::CoroutineClosure(..)
| ty::CoroutineWitness(..)
| ty::Never
| ty::Tuple(_)
| ty::UnsafeBinder(_)
| ty::Error(_)
| ty::Infer(IntVar(_) | FloatVar(_)) => tcx.types.u8,
ty::Bound(..)
| ty::Placeholder(_)
| ty::Infer(FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => {
bug!("`discriminant_ty` applied to unexpected type: {:?}", self)
}
}
}
/// Returns the type of metadata for (potentially wide) pointers to this type,
/// or the struct tail if the metadata type cannot be determined.
pub fn ptr_metadata_ty_or_tail(
self,
tcx: TyCtxt<'tcx>,
normalize: impl FnMut(Ty<'tcx>) -> Ty<'tcx>,
) -> Result<Ty<'tcx>, Ty<'tcx>> {
let tail = tcx.struct_tail_raw(self, &ObligationCause::dummy(), normalize, || {});
match tail.kind() {
// Sized types
ty::Infer(ty::IntVar(_) | ty::FloatVar(_))
| ty::Uint(_)
| ty::Int(_)
| ty::Bool
| ty::Float(_)
| ty::FnDef(..)
| ty::FnPtr(..)
| ty::RawPtr(..)
| ty::Char
| ty::Ref(..)
| ty::Coroutine(..)
| ty::CoroutineWitness(..)
| ty::Array(..)
| ty::Closure(..)
| ty::CoroutineClosure(..)
| ty::Never
| ty::Error(_)
// Extern types have metadata = ().
| ty::Foreign(..)
// If returned by `struct_tail_raw` this is a unit struct
// without any fields, or not a struct, and therefore is Sized.
| ty::Adt(..)
// If returned by `struct_tail_raw` this is the empty tuple,
// a.k.a. unit type, which is Sized
| ty::Tuple(..) => Ok(tcx.types.unit),
ty::Str | ty::Slice(_) => Ok(tcx.types.usize),
ty::Dynamic(_, _) => {
let dyn_metadata = tcx.require_lang_item(LangItem::DynMetadata, DUMMY_SP);
Ok(tcx.type_of(dyn_metadata).instantiate(tcx, &[tail.into()]))
}
// We don't know the metadata of `self`, but it must be equal to the
// metadata of `tail`.
ty::Param(_) | ty::Alias(..) => Err(tail),
| ty::UnsafeBinder(_) => todo!("FIXME(unsafe_binder)"),
ty::Infer(ty::TyVar(_))
| ty::Pat(..)
| ty::Bound(..)
| ty::Placeholder(..)
| ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => bug!(
"`ptr_metadata_ty_or_tail` applied to unexpected type: {self:?} (tail = {tail:?})"
),
}
}
/// Returns the type of metadata for (potentially wide) pointers to this type.
/// Causes an ICE if the metadata type cannot be determined.
pub fn ptr_metadata_ty(
self,
tcx: TyCtxt<'tcx>,
normalize: impl FnMut(Ty<'tcx>) -> Ty<'tcx>,
) -> Ty<'tcx> {
match self.ptr_metadata_ty_or_tail(tcx, normalize) {
Ok(metadata) => metadata,
Err(tail) => bug!(
"`ptr_metadata_ty` failed to get metadata for type: {self:?} (tail = {tail:?})"
),
}
}
/// Given a pointer or reference type, returns the type of the *pointee*'s
/// metadata. If it can't be determined exactly (perhaps due to still
/// being generic) then a projection through `ptr::Pointee` will be returned.
///
/// This is particularly useful for getting the type of the result of
/// [`UnOp::PtrMetadata`](crate::mir::UnOp::PtrMetadata).
///
/// Panics if `self` is not dereferenceable.
#[track_caller]
pub fn pointee_metadata_ty_or_projection(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
let Some(pointee_ty) = self.builtin_deref(true) else {
bug!("Type {self:?} is not a pointer or reference type")
};
if pointee_ty.has_trivial_sizedness(tcx, SizedTraitKind::Sized) {
tcx.types.unit
} else {
match pointee_ty.ptr_metadata_ty_or_tail(tcx, |x| x) {
Ok(metadata_ty) => metadata_ty,
Err(tail_ty) => {
let metadata_def_id = tcx.require_lang_item(LangItem::Metadata, DUMMY_SP);
Ty::new_projection(tcx, metadata_def_id, [tail_ty])
}
}
}
}
/// When we create a closure, we record its kind (i.e., what trait
/// it implements, constrained by how it uses its borrows) into its
/// [`ty::ClosureArgs`] or [`ty::CoroutineClosureArgs`] using a type
/// parameter. This is kind of a phantom type, except that the
/// most convenient thing for us to are the integral types. This
/// function converts such a special type into the closure
/// kind. To go the other way, use [`Ty::from_closure_kind`].
///
/// Note that during type checking, we use an inference variable
/// to represent the closure kind, because it has not yet been
/// inferred. Once upvar inference (in `rustc_hir_analysis/src/check/upvar.rs`)
/// is complete, that type variable will be unified with one of
/// the integral types.
///
/// ```rust,ignore (snippet of compiler code)
/// if let TyKind::Closure(def_id, args) = closure_ty.kind()
/// && let Some(closure_kind) = args.as_closure().kind_ty().to_opt_closure_kind()
/// {
/// println!("{closure_kind:?}");
/// } else if let TyKind::CoroutineClosure(def_id, args) = closure_ty.kind()
/// && let Some(closure_kind) = args.as_coroutine_closure().kind_ty().to_opt_closure_kind()
/// {
/// println!("{closure_kind:?}");
/// }
/// ```
///
/// After upvar analysis, you should instead use [`ty::ClosureArgs::kind()`]
/// or [`ty::CoroutineClosureArgs::kind()`] to assert that the `ClosureKind`
/// has been constrained instead of manually calling this method.
///
/// ```rust,ignore (snippet of compiler code)
/// if let TyKind::Closure(def_id, args) = closure_ty.kind()
/// {
/// println!("{:?}", args.as_closure().kind());
/// } else if let TyKind::CoroutineClosure(def_id, args) = closure_ty.kind()
/// {
/// println!("{:?}", args.as_coroutine_closure().kind());
/// }
/// ```
pub fn to_opt_closure_kind(self) -> Option<ty::ClosureKind> {
match self.kind() {
Int(int_ty) => match int_ty {
ty::IntTy::I8 => Some(ty::ClosureKind::Fn),
ty::IntTy::I16 => Some(ty::ClosureKind::FnMut),
ty::IntTy::I32 => Some(ty::ClosureKind::FnOnce),
_ => bug!("cannot convert type `{:?}` to a closure kind", self),
},
// "Bound" types appear in canonical queries when the
// closure type is not yet known, and `Placeholder` and `Param`
// may be encountered in generic `AsyncFnKindHelper` goals.
Bound(..) | Placeholder(_) | Param(_) | Infer(_) => None,
Error(_) => Some(ty::ClosureKind::Fn),
_ => bug!("cannot convert type `{:?}` to a closure kind", self),
}
}
/// Inverse of [`Ty::to_opt_closure_kind`]. See docs on that method
/// for explanation of the relationship between `Ty` and [`ty::ClosureKind`].
pub fn from_closure_kind(tcx: TyCtxt<'tcx>, kind: ty::ClosureKind) -> Ty<'tcx> {
match kind {
ty::ClosureKind::Fn => tcx.types.i8,
ty::ClosureKind::FnMut => tcx.types.i16,
ty::ClosureKind::FnOnce => tcx.types.i32,
}
}
/// Like [`Ty::to_opt_closure_kind`], but it caps the "maximum" closure kind
/// to `FnMut`. This is because although we have three capability states,
/// `AsyncFn`/`AsyncFnMut`/`AsyncFnOnce`, we only need to distinguish two coroutine
/// bodies: by-ref and by-value.
///
/// See the definition of `AsyncFn` and `AsyncFnMut` and the `CallRefFuture`
/// associated type for why we don't distinguish [`ty::ClosureKind::Fn`] and
/// [`ty::ClosureKind::FnMut`] for the purpose of the generated MIR bodies.
///
/// This method should be used when constructing a `Coroutine` out of a
/// `CoroutineClosure`, when the `Coroutine`'s `kind` field is being populated
/// directly from the `CoroutineClosure`'s `kind`.
pub fn from_coroutine_closure_kind(tcx: TyCtxt<'tcx>, kind: ty::ClosureKind) -> Ty<'tcx> {
match kind {
ty::ClosureKind::Fn | ty::ClosureKind::FnMut => tcx.types.i16,
ty::ClosureKind::FnOnce => tcx.types.i32,
}
}
/// Fast path helper for testing if a type is `Sized` or `MetaSized`.
///
/// Returning true means the type is known to implement the sizedness trait. Returning `false`
/// means nothing -- could be sized, might not be.
///
/// Note that we could never rely on the fact that a type such as `[_]` is trivially `!Sized`
/// because we could be in a type environment with a bound such as `[_]: Copy`. A function with
/// such a bound obviously never can be called, but that doesn't mean it shouldn't typecheck.
/// This is why this method doesn't return `Option<bool>`.
#[instrument(skip(tcx), level = "debug")]
pub fn has_trivial_sizedness(self, tcx: TyCtxt<'tcx>, sizedness: SizedTraitKind) -> bool {
match self.kind() {
ty::Infer(ty::IntVar(_) | ty::FloatVar(_))
| ty::Uint(_)
| ty::Int(_)
| ty::Bool
| ty::Float(_)
| ty::FnDef(..)
| ty::FnPtr(..)
| ty::UnsafeBinder(_)
| ty::RawPtr(..)
| ty::Char
| ty::Ref(..)
| ty::Coroutine(..)
| ty::CoroutineWitness(..)
| ty::Array(..)
| ty::Pat(..)
| ty::Closure(..)
| ty::CoroutineClosure(..)
| ty::Never
| ty::Error(_) => true,
ty::Str | ty::Slice(_) | ty::Dynamic(_, _) => match sizedness {
SizedTraitKind::Sized => false,
SizedTraitKind::MetaSized => true,
},
ty::Foreign(..) => match sizedness {
SizedTraitKind::Sized | SizedTraitKind::MetaSized => false,
},
ty::Tuple(tys) => tys.last().is_none_or(|ty| ty.has_trivial_sizedness(tcx, sizedness)),
ty::Adt(def, args) => def
.sizedness_constraint(tcx, sizedness)
.is_none_or(|ty| ty.instantiate(tcx, args).has_trivial_sizedness(tcx, sizedness)),
ty::Alias(..) | ty::Param(_) | ty::Placeholder(..) | ty::Bound(..) => false,
ty::Infer(ty::TyVar(_)) => false,
ty::Infer(ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) => {
bug!("`has_trivial_sizedness` applied to unexpected type: {:?}", self)
}
}
}
/// Fast path helper for primitives which are always `Copy` and which
/// have a side-effect-free `Clone` impl.
///
/// Returning true means the type is known to be pure and `Copy+Clone`.
/// Returning `false` means nothing -- could be `Copy`, might not be.
///
/// This is mostly useful for optimizations, as these are the types
/// on which we can replace cloning with dereferencing.
pub fn is_trivially_pure_clone_copy(self) -> bool {
match self.kind() {
ty::Bool | ty::Char | ty::Never => true,
// These aren't even `Clone`
ty::Str | ty::Slice(..) | ty::Foreign(..) | ty::Dynamic(..) => false,
ty::Infer(ty::InferTy::FloatVar(_) | ty::InferTy::IntVar(_))
| ty::Int(..)
| ty::Uint(..)
| ty::Float(..) => true,
// ZST which can't be named are fine.
ty::FnDef(..) => true,
ty::Array(element_ty, _len) => element_ty.is_trivially_pure_clone_copy(),
// A 100-tuple isn't "trivial", so doing this only for reasonable sizes.
ty::Tuple(field_tys) => {
field_tys.len() <= 3 && field_tys.iter().all(Self::is_trivially_pure_clone_copy)
}
ty::Pat(ty, _) => ty.is_trivially_pure_clone_copy(),
// Sometimes traits aren't implemented for every ABI or arity,
// because we can't be generic over everything yet.
ty::FnPtr(..) => false,
// Definitely absolutely not copy.
ty::Ref(_, _, hir::Mutability::Mut) => false,
// The standard library has a blanket Copy impl for shared references and raw pointers,
// for all unsized types.
ty::Ref(_, _, hir::Mutability::Not) | ty::RawPtr(..) => true,
ty::Coroutine(..) | ty::CoroutineWitness(..) => false,
// Might be, but not "trivial" so just giving the safe answer.
ty::Adt(..) | ty::Closure(..) | ty::CoroutineClosure(..) => false,
ty::UnsafeBinder(_) => false,
// Needs normalization or revealing to determine, so no is the safe answer.
ty::Alias(..) => false,
ty::Param(..) | ty::Placeholder(..) | ty::Bound(..) | ty::Infer(..) | ty::Error(..) => {
false
}
}
}
pub fn is_trivially_wf(self, tcx: TyCtxt<'tcx>) -> bool {
match *self.kind() {
ty::Bool
| ty::Char
| ty::Int(_)
| ty::Uint(_)
| ty::Float(_)
| ty::Str
| ty::Never
| ty::Param(_)
| ty::Placeholder(_)
| ty::Bound(..) => true,
ty::Slice(ty) => {
ty.is_trivially_wf(tcx) && ty.has_trivial_sizedness(tcx, SizedTraitKind::Sized)
}
ty::RawPtr(ty, _) => ty.is_trivially_wf(tcx),
ty::FnPtr(sig_tys, _) => {
sig_tys.skip_binder().inputs_and_output.iter().all(|ty| ty.is_trivially_wf(tcx))
}
ty::Ref(_, ty, _) => ty.is_global() && ty.is_trivially_wf(tcx),
ty::Infer(infer) => match infer {
ty::TyVar(_) => false,
ty::IntVar(_) | ty::FloatVar(_) => true,
ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_) => true,
},
ty::Adt(_, _)
| ty::Tuple(_)
| ty::Array(..)
| ty::Foreign(_)
| ty::Pat(_, _)
| ty::FnDef(..)
| ty::UnsafeBinder(..)
| ty::Dynamic(..)
| ty::Closure(..)
| ty::CoroutineClosure(..)
| ty::Coroutine(..)
| ty::CoroutineWitness(..)
| ty::Alias(..)
| ty::Error(_) => false,
}
}
/// If `self` is a primitive, return its [`Symbol`].
pub fn primitive_symbol(self) -> Option<Symbol> {
match self.kind() {
ty::Bool => Some(sym::bool),
ty::Char => Some(sym::char),
ty::Float(f) => match f {
ty::FloatTy::F16 => Some(sym::f16),
ty::FloatTy::F32 => Some(sym::f32),
ty::FloatTy::F64 => Some(sym::f64),
ty::FloatTy::F128 => Some(sym::f128),
},
ty::Int(f) => match f {
ty::IntTy::Isize => Some(sym::isize),
ty::IntTy::I8 => Some(sym::i8),
ty::IntTy::I16 => Some(sym::i16),
ty::IntTy::I32 => Some(sym::i32),
ty::IntTy::I64 => Some(sym::i64),
ty::IntTy::I128 => Some(sym::i128),
},
ty::Uint(f) => match f {
ty::UintTy::Usize => Some(sym::usize),
ty::UintTy::U8 => Some(sym::u8),
ty::UintTy::U16 => Some(sym::u16),
ty::UintTy::U32 => Some(sym::u32),
ty::UintTy::U64 => Some(sym::u64),
ty::UintTy::U128 => Some(sym::u128),
},
ty::Str => Some(sym::str),
_ => None,
}
}
pub fn is_c_void(self, tcx: TyCtxt<'_>) -> bool {
match self.kind() {
ty::Adt(adt, _) => tcx.is_lang_item(adt.did(), LangItem::CVoid),
_ => false,
}
}
pub fn is_async_drop_in_place_coroutine(self, tcx: TyCtxt<'_>) -> bool {
match self.kind() {
ty::Coroutine(def, ..) => tcx.is_async_drop_in_place_coroutine(*def),
_ => false,
}
}
/// Returns `true` when the outermost type cannot be further normalized,
/// resolved, or instantiated. This includes all primitive types, but also
/// things like ADTs and trait objects, since even if their arguments or
/// nested types may be further simplified, the outermost [`TyKind`] or
/// type constructor remains the same.
pub fn is_known_rigid(self) -> bool {
self.kind().is_known_rigid()
}
/// Iterator that walks `self` and any types reachable from
/// `self`, in depth-first order. Note that just walks the types
/// that appear in `self`, it does not descend into the fields of
/// structs or variants. For example:
///
/// ```text
/// isize => { isize }
/// Foo<Bar<isize>> => { Foo<Bar<isize>>, Bar<isize>, isize }
/// [isize] => { [isize], isize }
/// ```
pub fn walk(self) -> TypeWalker<TyCtxt<'tcx>> {
TypeWalker::new(self.into())
}
}
impl<'tcx> rustc_type_ir::inherent::Tys<TyCtxt<'tcx>> for &'tcx ty::List<Ty<'tcx>> {
fn inputs(self) -> &'tcx [Ty<'tcx>] {
self.split_last().unwrap().1
}
fn output(self) -> Ty<'tcx> {
*self.split_last().unwrap().0
}
}
impl<'tcx> rustc_type_ir::inherent::Symbol<TyCtxt<'tcx>> for Symbol {
fn is_kw_underscore_lifetime(self) -> bool {
self == kw::UnderscoreLifetime
}
}
// Some types are used a lot. Make sure they don't unintentionally get bigger.
#[cfg(target_pointer_width = "64")]
mod size_asserts {
use rustc_data_structures::static_assert_size;
use super::*;
// tidy-alphabetical-start
static_assert_size!(TyKind<'_>, 24);
static_assert_size!(ty::WithCachedTypeInfo<TyKind<'_>>, 48);
// tidy-alphabetical-end
}