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fuchsia / third_party / rust / 1e5ec0a12c73efdd9a492fdc7ab661d90dc5bcf5 / . / compiler / rustc_middle / src / ty / mod.rs
blob: 12cefc23233c04026cb69798f82a056874b8286e [file] [log] [blame]
//! Defines how the compiler represents types internally.
//!
//! Two important entities in this module are:
//!
//! - [`rustc_middle::ty::Ty`], used to represent the semantics of a type.
//! - [`rustc_middle::ty::TyCtxt`], the central data structure in the compiler.
//!
//! For more information, see ["The `ty` module: representing types"] in the rustc-dev-guide.
//!
//! ["The `ty` module: representing types"]: https://rustc-dev-guide.rust-lang.org/ty.html
#![allow(rustc::usage_of_ty_tykind)]
pub use self::fold::{FallibleTypeFolder, TypeFoldable, TypeFolder, TypeSuperFoldable};
pub use self::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor};
pub use self::AssocItemContainer::*;
pub use self::BorrowKind::*;
pub use self::IntVarValue::*;
pub use self::Variance::*;
use crate::error::{OpaqueHiddenTypeMismatch, TypeMismatchReason};
use crate::metadata::ModChild;
use crate::middle::privacy::EffectiveVisibilities;
use crate::mir::{Body, CoroutineLayout};
use crate::query::Providers;
use crate::traits::{self, Reveal};
use crate::ty;
use crate::ty::fast_reject::SimplifiedType;
use crate::ty::util::Discr;
pub use adt::*;
pub use assoc::*;
pub use generic_args::*;
pub use generics::*;
pub use intrinsic::IntrinsicDef;
use rustc_ast as ast;
use rustc_ast::expand::StrippedCfgItem;
use rustc_ast::node_id::NodeMap;
pub use rustc_ast_ir::{try_visit, Movability, Mutability};
use rustc_attr as attr;
use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
use rustc_data_structures::intern::Interned;
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc_data_structures::steal::Steal;
use rustc_data_structures::tagged_ptr::CopyTaggedPtr;
use rustc_data_structures::unord::UnordMap;
use rustc_errors::{Diag, ErrorGuaranteed, StashKey};
use rustc_hir as hir;
use rustc_hir::def::{CtorKind, CtorOf, DefKind, DocLinkResMap, LifetimeRes, Res};
use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, LocalDefId, LocalDefIdMap};
use rustc_index::IndexVec;
use rustc_macros::{
Decodable, Encodable, HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable,
};
use rustc_query_system::ich::StableHashingContext;
use rustc_serialize::{Decodable, Encodable};
use rustc_session::lint::LintBuffer;
pub use rustc_session::lint::RegisteredTools;
use rustc_span::hygiene::MacroKind;
use rustc_span::symbol::{kw, sym, Ident, Symbol};
use rustc_span::{ExpnId, ExpnKind, Span};
use rustc_target::abi::{Align, FieldIdx, Integer, IntegerType, VariantIdx};
pub use rustc_target::abi::{ReprFlags, ReprOptions};
pub use rustc_type_ir::{DebugWithInfcx, InferCtxtLike, WithInfcx};
pub use vtable::*;
use std::assert_matches::assert_matches;
use std::fmt::Debug;
use std::hash::{Hash, Hasher};
use std::marker::PhantomData;
use std::mem;
use std::num::NonZero;
use std::ptr::NonNull;
use std::{fmt, str};
pub use crate::ty::diagnostics::*;
pub use rustc_type_ir::ConstKind::{
Bound as BoundCt, Error as ErrorCt, Expr as ExprCt, Infer as InferCt, Param as ParamCt,
Placeholder as PlaceholderCt, Unevaluated, Value,
};
pub use rustc_type_ir::*;
pub use self::closure::{
analyze_coroutine_closure_captures, is_ancestor_or_same_capture, place_to_string_for_capture,
BorrowKind, CaptureInfo, CapturedPlace, ClosureTypeInfo, MinCaptureInformationMap,
MinCaptureList, RootVariableMinCaptureList, UpvarCapture, UpvarId, UpvarPath,
CAPTURE_STRUCT_LOCAL,
};
pub use self::consts::{
Const, ConstData, ConstInt, ConstKind, Expr, ScalarInt, UnevaluatedConst, ValTree,
};
pub use self::context::{
tls, CtxtInterners, CurrentGcx, DeducedParamAttrs, Feed, FreeRegionInfo, GlobalCtxt, Lift,
TyCtxt, TyCtxtFeed,
};
pub use self::instance::{Instance, InstanceDef, ReifyReason, ShortInstance, UnusedGenericParams};
pub use self::list::{List, ListWithCachedTypeInfo};
pub use self::parameterized::ParameterizedOverTcx;
pub use self::pattern::{Pattern, PatternKind};
pub use self::predicate::{
Clause, ClauseKind, CoercePredicate, ExistentialPredicate, ExistentialProjection,
ExistentialTraitRef, NormalizesTo, OutlivesPredicate, PolyCoercePredicate,
PolyExistentialPredicate, PolyExistentialProjection, PolyExistentialTraitRef,
PolyProjectionPredicate, PolyRegionOutlivesPredicate, PolySubtypePredicate, PolyTraitPredicate,
PolyTraitRef, PolyTypeOutlivesPredicate, Predicate, PredicateKind, ProjectionPredicate,
RegionOutlivesPredicate, SubtypePredicate, ToPolyTraitRef, ToPredicate, TraitPredicate,
TraitRef, TypeOutlivesPredicate,
};
pub use self::region::{
BoundRegion, BoundRegionKind, BoundRegionKind::*, EarlyParamRegion, LateParamRegion, Region,
RegionKind, RegionVid,
};
pub use self::rvalue_scopes::RvalueScopes;
pub use self::sty::{
AliasTy, Article, Binder, BoundTy, BoundTyKind, BoundVariableKind, CanonicalPolyFnSig,
ClosureArgs, ClosureArgsParts, CoroutineArgs, CoroutineArgsParts, CoroutineClosureArgs,
CoroutineClosureArgsParts, CoroutineClosureSignature, FnSig, GenSig, InlineConstArgs,
InlineConstArgsParts, ParamConst, ParamTy, PolyFnSig, TyKind, TypeAndMut, UpvarArgs,
VarianceDiagInfo,
};
pub use self::trait_def::TraitDef;
pub use self::typeck_results::{
CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, IsIdentity,
TypeckResults, UserType, UserTypeAnnotationIndex,
};
pub mod _match;
pub mod abstract_const;
pub mod adjustment;
pub mod cast;
pub mod codec;
pub mod error;
pub mod fast_reject;
pub mod flags;
pub mod fold;
pub mod inhabitedness;
pub mod layout;
pub mod normalize_erasing_regions;
pub mod pattern;
pub mod print;
pub mod relate;
pub mod trait_def;
pub mod util;
pub mod visit;
pub mod vtable;
pub mod walk;
mod adt;
mod assoc;
mod closure;
mod consts;
mod context;
mod diagnostics;
mod erase_regions;
mod generic_args;
mod generics;
mod impls_ty;
mod instance;
mod intrinsic;
mod list;
mod opaque_types;
mod parameterized;
mod predicate;
mod region;
mod rvalue_scopes;
mod structural_impls;
#[allow(hidden_glob_reexports)]
mod sty;
mod typeck_results;
// Data types
pub struct ResolverOutputs {
pub global_ctxt: ResolverGlobalCtxt,
pub ast_lowering: ResolverAstLowering,
}
#[derive(Debug)]
pub struct ResolverGlobalCtxt {
pub visibilities_for_hashing: Vec<(LocalDefId, Visibility)>,
/// Item with a given `LocalDefId` was defined during macro expansion with ID `ExpnId`.
pub expn_that_defined: FxHashMap<LocalDefId, ExpnId>,
pub effective_visibilities: EffectiveVisibilities,
pub extern_crate_map: FxHashMap<LocalDefId, CrateNum>,
pub maybe_unused_trait_imports: FxIndexSet<LocalDefId>,
pub module_children: LocalDefIdMap<Vec<ModChild>>,
pub glob_map: FxHashMap<LocalDefId, FxHashSet<Symbol>>,
pub main_def: Option<MainDefinition>,
pub trait_impls: FxIndexMap<DefId, Vec<LocalDefId>>,
/// A list of proc macro LocalDefIds, written out in the order in which
/// they are declared in the static array generated by proc_macro_harness.
pub proc_macros: Vec<LocalDefId>,
/// Mapping from ident span to path span for paths that don't exist as written, but that
/// exist under `std`. For example, wrote `str::from_utf8` instead of `std::str::from_utf8`.
pub confused_type_with_std_module: FxHashMap<Span, Span>,
pub doc_link_resolutions: FxHashMap<LocalDefId, DocLinkResMap>,
pub doc_link_traits_in_scope: FxHashMap<LocalDefId, Vec<DefId>>,
pub all_macro_rules: FxHashMap<Symbol, Res<ast::NodeId>>,
pub stripped_cfg_items: Steal<Vec<StrippedCfgItem>>,
}
/// Resolutions that should only be used for lowering.
/// This struct is meant to be consumed by lowering.
#[derive(Debug)]
pub struct ResolverAstLowering {
pub legacy_const_generic_args: FxHashMap<DefId, Option<Vec<usize>>>,
/// Resolutions for nodes that have a single resolution.
pub partial_res_map: NodeMap<hir::def::PartialRes>,
/// Resolutions for import nodes, which have multiple resolutions in different namespaces.
pub import_res_map: NodeMap<hir::def::PerNS<Option<Res<ast::NodeId>>>>,
/// Resolutions for labels (node IDs of their corresponding blocks or loops).
pub label_res_map: NodeMap<ast::NodeId>,
/// Resolutions for lifetimes.
pub lifetimes_res_map: NodeMap<LifetimeRes>,
/// Lifetime parameters that lowering will have to introduce.
pub extra_lifetime_params_map: NodeMap<Vec<(Ident, ast::NodeId, LifetimeRes)>>,
pub next_node_id: ast::NodeId,
pub node_id_to_def_id: NodeMap<LocalDefId>,
pub trait_map: NodeMap<Vec<hir::TraitCandidate>>,
/// List functions and methods for which lifetime elision was successful.
pub lifetime_elision_allowed: FxHashSet<ast::NodeId>,
/// Lints that were emitted by the resolver and early lints.
pub lint_buffer: Steal<LintBuffer>,
/// Information about functions signatures for delegation items expansion
pub delegation_fn_sigs: LocalDefIdMap<DelegationFnSig>,
}
#[derive(Debug)]
pub struct DelegationFnSig {
pub header: ast::FnHeader,
pub param_count: usize,
pub has_self: bool,
pub c_variadic: bool,
}
#[derive(Clone, Copy, Debug)]
pub struct MainDefinition {
pub res: Res<ast::NodeId>,
pub is_import: bool,
pub span: Span,
}
impl MainDefinition {
pub fn opt_fn_def_id(self) -> Option<DefId> {
if let Res::Def(DefKind::Fn, def_id) = self.res { Some(def_id) } else { None }
}
}
/// The "header" of an impl is everything outside the body: a Self type, a trait
/// ref (in the case of a trait impl), and a set of predicates (from the
/// bounds / where-clauses).
#[derive(Clone, Debug, TypeFoldable, TypeVisitable)]
pub struct ImplHeader<'tcx> {
pub impl_def_id: DefId,
pub impl_args: ty::GenericArgsRef<'tcx>,
pub self_ty: Ty<'tcx>,
pub trait_ref: Option<TraitRef<'tcx>>,
pub predicates: Vec<Predicate<'tcx>>,
}
#[derive(Copy, Clone, Debug, TyEncodable, TyDecodable, HashStable)]
pub struct ImplTraitHeader<'tcx> {
pub trait_ref: ty::EarlyBinder<ty::TraitRef<'tcx>>,
pub polarity: ImplPolarity,
pub unsafety: hir::Unsafety,
}
#[derive(Copy, Clone, PartialEq, Eq, Debug, TypeFoldable, TypeVisitable)]
pub enum ImplSubject<'tcx> {
Trait(TraitRef<'tcx>),
Inherent(Ty<'tcx>),
}
#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, HashStable, Debug)]
#[derive(TypeFoldable, TypeVisitable)]
pub enum ImplPolarity {
/// `impl Trait for Type`
Positive,
/// `impl !Trait for Type`
Negative,
/// `#[rustc_reservation_impl] impl Trait for Type`
///
/// This is a "stability hack", not a real Rust feature.
/// See #64631 for details.
Reservation,
}
impl fmt::Display for ImplPolarity {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Positive => f.write_str("positive"),
Self::Negative => f.write_str("negative"),
Self::Reservation => f.write_str("reservation"),
}
}
}
/// Polarity for a trait predicate. May either be negative or positive.
/// Distinguished from [`ImplPolarity`] since we never compute goals with
/// "reservation" level.
#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, HashStable, Debug)]
#[derive(TypeFoldable, TypeVisitable)]
pub enum PredicatePolarity {
/// `Type: Trait`
Positive,
/// `Type: !Trait`
Negative,
}
impl PredicatePolarity {
/// Flips polarity by turning `Positive` into `Negative` and `Negative` into `Positive`.
pub fn flip(&self) -> PredicatePolarity {
match self {
PredicatePolarity::Positive => PredicatePolarity::Negative,
PredicatePolarity::Negative => PredicatePolarity::Positive,
}
}
}
impl fmt::Display for PredicatePolarity {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::Positive => f.write_str("positive"),
Self::Negative => f.write_str("negative"),
}
}
}
#[derive(Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable, HashStable, Debug)]
#[derive(TypeFoldable, TypeVisitable)]
pub enum Asyncness {
Yes,
No,
}
impl Asyncness {
pub fn is_async(self) -> bool {
matches!(self, Asyncness::Yes)
}
}
#[derive(Clone, Debug, PartialEq, Eq, Copy, Hash, Encodable, Decodable, HashStable)]
pub enum Visibility<Id = LocalDefId> {
/// Visible everywhere (including in other crates).
Public,
/// Visible only in the given crate-local module.
Restricted(Id),
}
impl Visibility {
pub fn to_string(self, def_id: LocalDefId, tcx: TyCtxt<'_>) -> String {
match self {
ty::Visibility::Restricted(restricted_id) => {
if restricted_id.is_top_level_module() {
"pub(crate)".to_string()
} else if restricted_id == tcx.parent_module_from_def_id(def_id).to_local_def_id() {
"pub(self)".to_string()
} else {
format!("pub({})", tcx.item_name(restricted_id.to_def_id()))
}
}
ty::Visibility::Public => "pub".to_string(),
}
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
pub enum BoundConstness {
/// `Type: Trait`
NotConst,
/// `Type: const Trait`
Const,
/// `Type: ~const Trait`
///
/// Requires resolving to const only when we are in a const context.
ConstIfConst,
}
impl BoundConstness {
pub fn as_str(self) -> &'static str {
match self {
Self::NotConst => "",
Self::Const => "const",
Self::ConstIfConst => "~const",
}
}
}
impl fmt::Display for BoundConstness {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Self::NotConst => f.write_str("normal"),
Self::Const => f.write_str("const"),
Self::ConstIfConst => f.write_str("~const"),
}
}
}
#[derive(Clone, Debug, PartialEq, Eq, Copy, Hash, TyEncodable, TyDecodable, HashStable)]
#[derive(TypeFoldable, TypeVisitable)]
pub struct ClosureSizeProfileData<'tcx> {
/// Tuple containing the types of closure captures before the feature `capture_disjoint_fields`
pub before_feature_tys: Ty<'tcx>,
/// Tuple containing the types of closure captures after the feature `capture_disjoint_fields`
pub after_feature_tys: Ty<'tcx>,
}
impl TyCtxt<'_> {
#[inline]
pub fn opt_parent(self, id: DefId) -> Option<DefId> {
self.def_key(id).parent.map(|index| DefId { index, ..id })
}
#[inline]
#[track_caller]
pub fn parent(self, id: DefId) -> DefId {
match self.opt_parent(id) {
Some(id) => id,
// not `unwrap_or_else` to avoid breaking caller tracking
None => bug!("{id:?} doesn't have a parent"),
}
}
#[inline]
#[track_caller]
pub fn opt_local_parent(self, id: LocalDefId) -> Option<LocalDefId> {
self.opt_parent(id.to_def_id()).map(DefId::expect_local)
}
#[inline]
#[track_caller]
pub fn local_parent(self, id: impl Into<LocalDefId>) -> LocalDefId {
self.parent(id.into().to_def_id()).expect_local()
}
pub fn is_descendant_of(self, mut descendant: DefId, ancestor: DefId) -> bool {
if descendant.krate != ancestor.krate {
return false;
}
while descendant != ancestor {
match self.opt_parent(descendant) {
Some(parent) => descendant = parent,
None => return false,
}
}
true
}
}
impl<Id> Visibility<Id> {
pub fn is_public(self) -> bool {
matches!(self, Visibility::Public)
}
pub fn map_id<OutId>(self, f: impl FnOnce(Id) -> OutId) -> Visibility<OutId> {
match self {
Visibility::Public => Visibility::Public,
Visibility::Restricted(id) => Visibility::Restricted(f(id)),
}
}
}
impl<Id: Into<DefId>> Visibility<Id> {
pub fn to_def_id(self) -> Visibility<DefId> {
self.map_id(Into::into)
}
/// Returns `true` if an item with this visibility is accessible from the given module.
pub fn is_accessible_from(self, module: impl Into<DefId>, tcx: TyCtxt<'_>) -> bool {
match self {
// Public items are visible everywhere.
Visibility::Public => true,
Visibility::Restricted(id) => tcx.is_descendant_of(module.into(), id.into()),
}
}
/// Returns `true` if this visibility is at least as accessible as the given visibility
pub fn is_at_least(self, vis: Visibility<impl Into<DefId>>, tcx: TyCtxt<'_>) -> bool {
match vis {
Visibility::Public => self.is_public(),
Visibility::Restricted(id) => self.is_accessible_from(id, tcx),
}
}
}
impl Visibility<DefId> {
pub fn expect_local(self) -> Visibility {
self.map_id(|id| id.expect_local())
}
/// Returns `true` if this item is visible anywhere in the local crate.
pub fn is_visible_locally(self) -> bool {
match self {
Visibility::Public => true,
Visibility::Restricted(def_id) => def_id.is_local(),
}
}
}
/// The crate variances map is computed during typeck and contains the
/// variance of every item in the local crate. You should not use it
/// directly, because to do so will make your pass dependent on the
/// HIR of every item in the local crate. Instead, use
/// `tcx.variances_of()` to get the variance for a *particular*
/// item.
#[derive(HashStable, Debug)]
pub struct CrateVariancesMap<'tcx> {
/// For each item with generics, maps to a vector of the variance
/// of its generics. If an item has no generics, it will have no
/// entry.
pub variances: DefIdMap<&'tcx [ty::Variance]>,
}
// Contains information needed to resolve types and (in the future) look up
// the types of AST nodes.
#[derive(Copy, Clone, PartialEq, Eq, Hash)]
pub struct CReaderCacheKey {
pub cnum: Option<CrateNum>,
pub pos: usize,
}
/// Use this rather than `TyKind`, whenever possible.
#[derive(Copy, Clone, PartialEq, Eq, Hash, HashStable)]
#[rustc_diagnostic_item = "Ty"]
#[rustc_pass_by_value]
pub struct Ty<'tcx>(Interned<'tcx, WithCachedTypeInfo<TyKind<'tcx>>>);
impl<'tcx> rustc_type_ir::inherent::IntoKind for Ty<'tcx> {
type Kind = TyKind<'tcx>;
fn kind(self) -> TyKind<'tcx> {
*self.kind()
}
}
impl<'tcx> rustc_type_ir::visit::Flags for Ty<'tcx> {
fn flags(&self) -> TypeFlags {
self.0.flags
}
fn outer_exclusive_binder(&self) -> DebruijnIndex {
self.0.outer_exclusive_binder
}
}
impl EarlyParamRegion {
/// Does this early bound region have a name? Early bound regions normally
/// always have names except when using anonymous lifetimes (`'_`).
pub fn has_name(&self) -> bool {
self.name != kw::UnderscoreLifetime && self.name != kw::Empty
}
}
/// The crate outlives map is computed during typeck and contains the
/// outlives of every item in the local crate. You should not use it
/// directly, because to do so will make your pass dependent on the
/// HIR of every item in the local crate. Instead, use
/// `tcx.inferred_outlives_of()` to get the outlives for a *particular*
/// item.
#[derive(HashStable, Debug)]
pub struct CratePredicatesMap<'tcx> {
/// For each struct with outlive bounds, maps to a vector of the
/// predicate of its outlive bounds. If an item has no outlives
/// bounds, it will have no entry.
pub predicates: DefIdMap<&'tcx [(Clause<'tcx>, Span)]>,
}
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Term<'tcx> {
ptr: NonNull<()>,
marker: PhantomData<(Ty<'tcx>, Const<'tcx>)>,
}
#[cfg(parallel_compiler)]
unsafe impl<'tcx> rustc_data_structures::sync::DynSend for Term<'tcx> where
&'tcx (Ty<'tcx>, Const<'tcx>): rustc_data_structures::sync::DynSend
{
}
#[cfg(parallel_compiler)]
unsafe impl<'tcx> rustc_data_structures::sync::DynSync for Term<'tcx> where
&'tcx (Ty<'tcx>, Const<'tcx>): rustc_data_structures::sync::DynSync
{
}
unsafe impl<'tcx> Send for Term<'tcx> where &'tcx (Ty<'tcx>, Const<'tcx>): Send {}
unsafe impl<'tcx> Sync for Term<'tcx> where &'tcx (Ty<'tcx>, Const<'tcx>): Sync {}
impl Debug for Term<'_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let data = if let Some(ty) = self.ty() {
format!("Term::Ty({ty:?})")
} else if let Some(ct) = self.ct() {
format!("Term::Ct({ct:?})")
} else {
unreachable!()
};
f.write_str(&data)
}
}
impl<'tcx> From<Ty<'tcx>> for Term<'tcx> {
fn from(ty: Ty<'tcx>) -> Self {
TermKind::Ty(ty).pack()
}
}
impl<'tcx> From<Const<'tcx>> for Term<'tcx> {
fn from(c: Const<'tcx>) -> Self {
TermKind::Const(c).pack()
}
}
impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for Term<'tcx> {
fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
self.unpack().hash_stable(hcx, hasher);
}
}
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Term<'tcx> {
fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
folder: &mut F,
) -> Result<Self, F::Error> {
Ok(self.unpack().try_fold_with(folder)?.pack())
}
}
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Term<'tcx> {
fn visit_with<V: TypeVisitor<TyCtxt<'tcx>>>(&self, visitor: &mut V) -> V::Result {
self.unpack().visit_with(visitor)
}
}
impl<'tcx, E: TyEncoder<I = TyCtxt<'tcx>>> Encodable<E> for Term<'tcx> {
fn encode(&self, e: &mut E) {
self.unpack().encode(e)
}
}
impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for Term<'tcx> {
fn decode(d: &mut D) -> Self {
let res: TermKind<'tcx> = Decodable::decode(d);
res.pack()
}
}
impl<'tcx> Term<'tcx> {
#[inline]
pub fn unpack(self) -> TermKind<'tcx> {
let ptr =
unsafe { self.ptr.map_addr(|addr| NonZero::new_unchecked(addr.get() & !TAG_MASK)) };
// SAFETY: use of `Interned::new_unchecked` here is ok because these
// pointers were originally created from `Interned` types in `pack()`,
// and this is just going in the other direction.
unsafe {
match self.ptr.addr().get() & TAG_MASK {
TYPE_TAG => TermKind::Ty(Ty(Interned::new_unchecked(
ptr.cast::<WithCachedTypeInfo<ty::TyKind<'tcx>>>().as_ref(),
))),
CONST_TAG => TermKind::Const(ty::Const(Interned::new_unchecked(
ptr.cast::<WithCachedTypeInfo<ty::ConstData<'tcx>>>().as_ref(),
))),
_ => core::intrinsics::unreachable(),
}
}
}
pub fn ty(&self) -> Option<Ty<'tcx>> {
if let TermKind::Ty(ty) = self.unpack() { Some(ty) } else { None }
}
pub fn ct(&self) -> Option<Const<'tcx>> {
if let TermKind::Const(c) = self.unpack() { Some(c) } else { None }
}
pub fn into_arg(self) -> GenericArg<'tcx> {
match self.unpack() {
TermKind::Ty(ty) => ty.into(),
TermKind::Const(c) => c.into(),
}
}
/// This function returns the inner `AliasTy` for a `ty::Alias` or `ConstKind::Unevaluated`.
pub fn to_alias_ty(&self, tcx: TyCtxt<'tcx>) -> Option<AliasTy<'tcx>> {
match self.unpack() {
TermKind::Ty(ty) => match *ty.kind() {
ty::Alias(_kind, alias_ty) => Some(alias_ty),
_ => None,
},
TermKind::Const(ct) => match ct.kind() {
ConstKind::Unevaluated(uv) => Some(AliasTy::new(tcx, uv.def, uv.args)),
_ => None,
},
}
}
pub fn is_infer(&self) -> bool {
match self.unpack() {
TermKind::Ty(ty) => ty.is_ty_var(),
TermKind::Const(ct) => ct.is_ct_infer(),
}
}
}
const TAG_MASK: usize = 0b11;
const TYPE_TAG: usize = 0b00;
const CONST_TAG: usize = 0b01;
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, TyEncodable, TyDecodable)]
#[derive(HashStable, TypeFoldable, TypeVisitable)]
pub enum TermKind<'tcx> {
Ty(Ty<'tcx>),
Const(Const<'tcx>),
}
impl<'tcx> TermKind<'tcx> {
#[inline]
fn pack(self) -> Term<'tcx> {
let (tag, ptr) = match self {
TermKind::Ty(ty) => {
// Ensure we can use the tag bits.
assert_eq!(mem::align_of_val(&*ty.0.0) & TAG_MASK, 0);
(TYPE_TAG, NonNull::from(ty.0.0).cast())
}
TermKind::Const(ct) => {
// Ensure we can use the tag bits.
assert_eq!(mem::align_of_val(&*ct.0.0) & TAG_MASK, 0);
(CONST_TAG, NonNull::from(ct.0.0).cast())
}
};
Term { ptr: ptr.map_addr(|addr| addr | tag), marker: PhantomData }
}
}
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum ParamTerm {
Ty(ParamTy),
Const(ParamConst),
}
impl ParamTerm {
pub fn index(self) -> usize {
match self {
ParamTerm::Ty(ty) => ty.index as usize,
ParamTerm::Const(ct) => ct.index as usize,
}
}
}
#[derive(Copy, Clone, Eq, PartialEq, Debug)]
pub enum TermVid {
Ty(ty::TyVid),
Const(ty::ConstVid),
}
impl From<ty::TyVid> for TermVid {
fn from(value: ty::TyVid) -> Self {
TermVid::Ty(value)
}
}
impl From<ty::ConstVid> for TermVid {
fn from(value: ty::ConstVid) -> Self {
TermVid::Const(value)
}
}
/// Represents the bounds declared on a particular set of type
/// parameters. Should eventually be generalized into a flag list of
/// where-clauses. You can obtain an `InstantiatedPredicates` list from a
/// `GenericPredicates` by using the `instantiate` method. Note that this method
/// reflects an important semantic invariant of `InstantiatedPredicates`: while
/// the `GenericPredicates` are expressed in terms of the bound type
/// parameters of the impl/trait/whatever, an `InstantiatedPredicates` instance
/// represented a set of bounds for some particular instantiation,
/// meaning that the generic parameters have been instantiated with
/// their values.
///
/// Example:
/// ```ignore (illustrative)
/// struct Foo<T, U: Bar<T>> { ... }
/// ```
/// Here, the `GenericPredicates` for `Foo` would contain a list of bounds like
/// `[[], [U:Bar<T>]]`. Now if there were some particular reference
/// like `Foo<isize,usize>`, then the `InstantiatedPredicates` would be `[[],
/// [usize:Bar<isize>]]`.
#[derive(Clone, Debug, TypeFoldable, TypeVisitable)]
pub struct InstantiatedPredicates<'tcx> {
pub predicates: Vec<Clause<'tcx>>,
pub spans: Vec<Span>,
}
impl<'tcx> InstantiatedPredicates<'tcx> {
pub fn empty() -> InstantiatedPredicates<'tcx> {
InstantiatedPredicates { predicates: vec![], spans: vec![] }
}
pub fn is_empty(&self) -> bool {
self.predicates.is_empty()
}
pub fn iter(&self) -> <&Self as IntoIterator>::IntoIter {
self.into_iter()
}
}
impl<'tcx> IntoIterator for InstantiatedPredicates<'tcx> {
type Item = (Clause<'tcx>, Span);
type IntoIter = std::iter::Zip<std::vec::IntoIter<Clause<'tcx>>, std::vec::IntoIter<Span>>;
fn into_iter(self) -> Self::IntoIter {
debug_assert_eq!(self.predicates.len(), self.spans.len());
std::iter::zip(self.predicates, self.spans)
}
}
impl<'a, 'tcx> IntoIterator for &'a InstantiatedPredicates<'tcx> {
type Item = (Clause<'tcx>, Span);
type IntoIter = std::iter::Zip<
std::iter::Copied<std::slice::Iter<'a, Clause<'tcx>>>,
std::iter::Copied<std::slice::Iter<'a, Span>>,
>;
fn into_iter(self) -> Self::IntoIter {
debug_assert_eq!(self.predicates.len(), self.spans.len());
std::iter::zip(self.predicates.iter().copied(), self.spans.iter().copied())
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
#[derive(TypeFoldable, TypeVisitable)]
pub struct OpaqueTypeKey<'tcx> {
pub def_id: LocalDefId,
pub args: GenericArgsRef<'tcx>,
}
impl<'tcx> OpaqueTypeKey<'tcx> {
pub fn iter_captured_args(
self,
tcx: TyCtxt<'tcx>,
) -> impl Iterator<Item = (usize, GenericArg<'tcx>)> {
std::iter::zip(self.args, tcx.variances_of(self.def_id)).enumerate().filter_map(
|(i, (arg, v))| match (arg.unpack(), v) {
(_, ty::Invariant) => Some((i, arg)),
(ty::GenericArgKind::Lifetime(_), ty::Bivariant) => None,
_ => bug!("unexpected opaque type arg variance"),
},
)
}
pub fn fold_captured_lifetime_args(
self,
tcx: TyCtxt<'tcx>,
mut f: impl FnMut(Region<'tcx>) -> Region<'tcx>,
) -> Self {
let Self { def_id, args } = self;
let args = std::iter::zip(args, tcx.variances_of(def_id)).map(|(arg, v)| {
match (arg.unpack(), v) {
(ty::GenericArgKind::Lifetime(_), ty::Bivariant) => arg,
(ty::GenericArgKind::Lifetime(lt), _) => f(lt).into(),
_ => arg,
}
});
let args = tcx.mk_args_from_iter(args);
Self { def_id, args }
}
}
#[derive(Copy, Clone, Debug, TypeFoldable, TypeVisitable, HashStable, TyEncodable, TyDecodable)]
pub struct OpaqueHiddenType<'tcx> {
/// The span of this particular definition of the opaque type. So
/// for example:
///
/// ```ignore (incomplete snippet)
/// type Foo = impl Baz;
/// fn bar() -> Foo {
/// // ^^^ This is the span we are looking for!
/// }
/// ```
///
/// In cases where the fn returns `(impl Trait, impl Trait)` or
/// other such combinations, the result is currently
/// over-approximated, but better than nothing.
pub span: Span,
/// The type variable that represents the value of the opaque type
/// that we require. In other words, after we compile this function,
/// we will be created a constraint like:
/// ```ignore (pseudo-rust)
/// Foo<'a, T> = ?C
/// ```
/// where `?C` is the value of this type variable. =) It may
/// naturally refer to the type and lifetime parameters in scope
/// in this function, though ultimately it should only reference
/// those that are arguments to `Foo` in the constraint above. (In
/// other words, `?C` should not include `'b`, even though it's a
/// lifetime parameter on `foo`.)
pub ty: Ty<'tcx>,
}
impl<'tcx> OpaqueHiddenType<'tcx> {
pub fn build_mismatch_error(
&self,
other: &Self,
opaque_def_id: LocalDefId,
tcx: TyCtxt<'tcx>,
) -> Result<Diag<'tcx>, ErrorGuaranteed> {
// We used to cancel here for slightly better error messages, but
// cancelling stashed diagnostics is no longer allowed because it
// causes problems when tracking whether errors have actually
// occurred.
tcx.sess.dcx().try_steal_modify_and_emit_err(
tcx.def_span(opaque_def_id),
StashKey::OpaqueHiddenTypeMismatch,
|_err| {},
);
(self.ty, other.ty).error_reported()?;
// Found different concrete types for the opaque type.
let sub_diag = if self.span == other.span {
TypeMismatchReason::ConflictType { span: self.span }
} else {
TypeMismatchReason::PreviousUse { span: self.span }
};
Ok(tcx.dcx().create_err(OpaqueHiddenTypeMismatch {
self_ty: self.ty,
other_ty: other.ty,
other_span: other.span,
sub: sub_diag,
}))
}
#[instrument(level = "debug", skip(tcx), ret)]
pub fn remap_generic_params_to_declaration_params(
self,
opaque_type_key: OpaqueTypeKey<'tcx>,
tcx: TyCtxt<'tcx>,
// typeck errors have subpar spans for opaque types, so delay error reporting until borrowck.
ignore_errors: bool,
) -> Self {
let OpaqueTypeKey { def_id, args } = opaque_type_key;
// Use args to build up a reverse map from regions to their
// identity mappings. This is necessary because of `impl
// Trait` lifetimes are computed by replacing existing
// lifetimes with 'static and remapping only those used in the
// `impl Trait` return type, resulting in the parameters
// shifting.
let id_args = GenericArgs::identity_for_item(tcx, def_id);
debug!(?id_args);
// This zip may have several times the same lifetime in `args` paired with a different
// lifetime from `id_args`. Simply `collect`ing the iterator is the correct behaviour:
// it will pick the last one, which is the one we introduced in the impl-trait desugaring.
let map = args.iter().zip(id_args).collect();
debug!("map = {:#?}", map);
// Convert the type from the function into a type valid outside
// the function, by replacing invalid regions with 'static,
// after producing an error for each of them.
self.fold_with(&mut opaque_types::ReverseMapper::new(tcx, map, self.span, ignore_errors))
}
}
/// The "placeholder index" fully defines a placeholder region, type, or const. Placeholders are
/// identified by both a universe, as well as a name residing within that universe. Distinct bound
/// regions/types/consts within the same universe simply have an unknown relationship to one
/// another.
#[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
#[derive(HashStable, TyEncodable, TyDecodable)]
pub struct Placeholder<T> {
pub universe: UniverseIndex,
pub bound: T,
}
pub type PlaceholderRegion = Placeholder<BoundRegion>;
impl rustc_type_ir::inherent::PlaceholderLike for PlaceholderRegion {
fn universe(self) -> UniverseIndex {
self.universe
}
fn var(self) -> BoundVar {
self.bound.var
}
fn with_updated_universe(self, ui: UniverseIndex) -> Self {
Placeholder { universe: ui, ..self }
}
fn new(ui: UniverseIndex, var: BoundVar) -> Self {
Placeholder { universe: ui, bound: BoundRegion { var, kind: BoundRegionKind::BrAnon } }
}
}
pub type PlaceholderType = Placeholder<BoundTy>;
impl rustc_type_ir::inherent::PlaceholderLike for PlaceholderType {
fn universe(self) -> UniverseIndex {
self.universe
}
fn var(self) -> BoundVar {
self.bound.var
}
fn with_updated_universe(self, ui: UniverseIndex) -> Self {
Placeholder { universe: ui, ..self }
}
fn new(ui: UniverseIndex, var: BoundVar) -> Self {
Placeholder { universe: ui, bound: BoundTy { var, kind: BoundTyKind::Anon } }
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable)]
#[derive(TyEncodable, TyDecodable)]
pub struct BoundConst<'tcx> {
pub var: BoundVar,
pub ty: Ty<'tcx>,
}
pub type PlaceholderConst = Placeholder<BoundVar>;
impl rustc_type_ir::inherent::PlaceholderLike for PlaceholderConst {
fn universe(self) -> UniverseIndex {
self.universe
}
fn var(self) -> BoundVar {
self.bound
}
fn with_updated_universe(self, ui: UniverseIndex) -> Self {
Placeholder { universe: ui, ..self }
}
fn new(ui: UniverseIndex, var: BoundVar) -> Self {
Placeholder { universe: ui, bound: var }
}
}
pub type Clauses<'tcx> = &'tcx ListWithCachedTypeInfo<Clause<'tcx>>;
impl<'tcx> rustc_type_ir::visit::Flags for Clauses<'tcx> {
fn flags(&self) -> TypeFlags {
(**self).flags()
}
fn outer_exclusive_binder(&self) -> DebruijnIndex {
(**self).outer_exclusive_binder()
}
}
/// When interacting with the type system we must provide information about the
/// environment. `ParamEnv` is the type that represents this information. See the
/// [dev guide chapter][param_env_guide] for more information.
///
/// [param_env_guide]: https://rustc-dev-guide.rust-lang.org/param_env/param_env_summary.html
#[derive(Copy, Clone, Hash, PartialEq, Eq)]
pub struct ParamEnv<'tcx> {
/// This packs both caller bounds and the reveal enum into one pointer.
///
/// Caller bounds are `Obligation`s that the caller must satisfy. This is
/// basically the set of bounds on the in-scope type parameters, translated
/// into `Obligation`s, and elaborated and normalized.
///
/// Use the `caller_bounds()` method to access.
///
/// Typically, this is `Reveal::UserFacing`, but during codegen we
/// want `Reveal::All`.
///
/// Note: This is packed, use the reveal() method to access it.
packed: CopyTaggedPtr<Clauses<'tcx>, ParamTag, true>,
}
#[derive(Copy, Clone)]
struct ParamTag {
reveal: traits::Reveal,
}
rustc_data_structures::impl_tag! {
impl Tag for ParamTag;
ParamTag { reveal: traits::Reveal::UserFacing },
ParamTag { reveal: traits::Reveal::All },
}
impl<'tcx> fmt::Debug for ParamEnv<'tcx> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("ParamEnv")
.field("caller_bounds", &self.caller_bounds())
.field("reveal", &self.reveal())
.finish()
}
}
impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ParamEnv<'tcx> {
fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
self.caller_bounds().hash_stable(hcx, hasher);
self.reveal().hash_stable(hcx, hasher);
}
}
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for ParamEnv<'tcx> {
fn try_fold_with<F: ty::fold::FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
folder: &mut F,
) -> Result<Self, F::Error> {
Ok(ParamEnv::new(
self.caller_bounds().try_fold_with(folder)?,
self.reveal().try_fold_with(folder)?,
))
}
}
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for ParamEnv<'tcx> {
fn visit_with<V: TypeVisitor<TyCtxt<'tcx>>>(&self, visitor: &mut V) -> V::Result {
try_visit!(self.caller_bounds().visit_with(visitor));
self.reveal().visit_with(visitor)
}
}
impl<'tcx> ParamEnv<'tcx> {
/// Construct a trait environment suitable for contexts where
/// there are no where-clauses in scope. Hidden types (like `impl
/// Trait`) are left hidden. In majority of cases it is incorrect
/// to use an empty environment. See the [dev guide section][param_env_guide]
/// for information on what a `ParamEnv` is and how to acquire one.
///
/// [param_env_guide]: https://rustc-dev-guide.rust-lang.org/param_env/param_env_summary.html
#[inline]
pub fn empty() -> Self {
Self::new(ListWithCachedTypeInfo::empty(), Reveal::UserFacing)
}
#[inline]
pub fn caller_bounds(self) -> Clauses<'tcx> {
self.packed.pointer()
}
#[inline]
pub fn reveal(self) -> traits::Reveal {
self.packed.tag().reveal
}
/// Construct a trait environment with no where-clauses in scope
/// where the values of all `impl Trait` and other hidden types
/// are revealed. This is suitable for monomorphized, post-typeck
/// environments like codegen or doing optimizations.
///
/// N.B., if you want to have predicates in scope, use `ParamEnv::new`,
/// or invoke `param_env.with_reveal_all()`.
#[inline]
pub fn reveal_all() -> Self {
Self::new(ListWithCachedTypeInfo::empty(), Reveal::All)
}
/// Construct a trait environment with the given set of predicates.
#[inline]
pub fn new(caller_bounds: Clauses<'tcx>, reveal: Reveal) -> Self {
ty::ParamEnv { packed: CopyTaggedPtr::new(caller_bounds, ParamTag { reveal }) }
}
pub fn with_user_facing(mut self) -> Self {
self.packed.set_tag(ParamTag { reveal: Reveal::UserFacing, ..self.packed.tag() });
self
}
/// Returns a new parameter environment with the same clauses, but
/// which "reveals" the true results of projections in all cases
/// (even for associated types that are specializable). This is
/// the desired behavior during codegen and certain other special
/// contexts; normally though we want to use `Reveal::UserFacing`,
/// which is the default.
/// All opaque types in the caller_bounds of the `ParamEnv`
/// will be normalized to their underlying types.
/// See PR #65989 and issue #65918 for more details
pub fn with_reveal_all_normalized(self, tcx: TyCtxt<'tcx>) -> Self {
if self.packed.tag().reveal == traits::Reveal::All {
return self;
}
ParamEnv::new(tcx.reveal_opaque_types_in_bounds(self.caller_bounds()), Reveal::All)
}
/// Returns this same environment but with no caller bounds.
#[inline]
pub fn without_caller_bounds(self) -> Self {
Self::new(ListWithCachedTypeInfo::empty(), self.reveal())
}
/// Creates a pair of param-env and value for use in queries.
pub fn and<T: TypeVisitable<TyCtxt<'tcx>>>(self, value: T) -> ParamEnvAnd<'tcx, T> {
ParamEnvAnd { param_env: self, value }
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TypeFoldable, TypeVisitable)]
#[derive(HashStable)]
pub struct ParamEnvAnd<'tcx, T> {
pub param_env: ParamEnv<'tcx>,
pub value: T,
}
impl<'tcx, T> ParamEnvAnd<'tcx, T> {
pub fn into_parts(self) -> (ParamEnv<'tcx>, T) {
(self.param_env, self.value)
}
}
#[derive(Copy, Clone, Debug, HashStable, Encodable, Decodable)]
pub struct Destructor {
/// The `DefId` of the destructor method
pub did: DefId,
/// The constness of the destructor method
pub constness: hir::Constness,
}
#[derive(Clone, Copy, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
pub struct VariantFlags(u8);
bitflags::bitflags! {
impl VariantFlags: u8 {
const NO_VARIANT_FLAGS = 0;
/// Indicates whether the field list of this variant is `#[non_exhaustive]`.
const IS_FIELD_LIST_NON_EXHAUSTIVE = 1 << 0;
/// Indicates whether this variant was obtained as part of recovering from
/// a syntactic error. May be incomplete or bogus.
const IS_RECOVERED = 1 << 1;
/// Indicates whether this variant has unnamed fields.
const HAS_UNNAMED_FIELDS = 1 << 2;
}
}
rustc_data_structures::external_bitflags_debug! { VariantFlags }
/// Definition of a variant -- a struct's fields or an enum variant.
#[derive(Debug, HashStable, TyEncodable, TyDecodable)]
pub struct VariantDef {
/// `DefId` that identifies the variant itself.
/// If this variant belongs to a struct or union, then this is a copy of its `DefId`.
pub def_id: DefId,
/// `DefId` that identifies the variant's constructor.
/// If this variant is a struct variant, then this is `None`.
pub ctor: Option<(CtorKind, DefId)>,
/// Variant or struct name, maybe empty for anonymous adt (struct or union).
pub name: Symbol,
/// Discriminant of this variant.
pub discr: VariantDiscr,
/// Fields of this variant.
pub fields: IndexVec<FieldIdx, FieldDef>,
/// Flags of the variant (e.g. is field list non-exhaustive)?
flags: VariantFlags,
}
impl VariantDef {
/// Creates a new `VariantDef`.
///
/// `variant_did` is the `DefId` that identifies the enum variant (if this `VariantDef`
/// represents an enum variant).
///
/// `ctor_did` is the `DefId` that identifies the constructor of unit or
/// tuple-variants/structs. If this is a `struct`-variant then this should be `None`.
///
/// `parent_did` is the `DefId` of the `AdtDef` representing the enum or struct that
/// owns this variant. It is used for checking if a struct has `#[non_exhaustive]` w/out having
/// to go through the redirect of checking the ctor's attributes - but compiling a small crate
/// requires loading the `AdtDef`s for all the structs in the universe (e.g., coherence for any
/// built-in trait), and we do not want to load attributes twice.
///
/// If someone speeds up attribute loading to not be a performance concern, they can
/// remove this hack and use the constructor `DefId` everywhere.
pub fn new(
name: Symbol,
variant_did: Option<DefId>,
ctor: Option<(CtorKind, DefId)>,
discr: VariantDiscr,
fields: IndexVec<FieldIdx, FieldDef>,
adt_kind: AdtKind,
parent_did: DefId,
recovered: bool,
is_field_list_non_exhaustive: bool,
has_unnamed_fields: bool,
) -> Self {
debug!(
"VariantDef::new(name = {:?}, variant_did = {:?}, ctor = {:?}, discr = {:?},
fields = {:?}, adt_kind = {:?}, parent_did = {:?}, has_unnamed_fields = {:?})",
name, variant_did, ctor, discr, fields, adt_kind, parent_did, has_unnamed_fields,
);
let mut flags = VariantFlags::NO_VARIANT_FLAGS;
if is_field_list_non_exhaustive {
flags |= VariantFlags::IS_FIELD_LIST_NON_EXHAUSTIVE;
}
if recovered {
flags |= VariantFlags::IS_RECOVERED;
}
if has_unnamed_fields {
flags |= VariantFlags::HAS_UNNAMED_FIELDS;
}
VariantDef { def_id: variant_did.unwrap_or(parent_did), ctor, name, discr, fields, flags }
}
/// Is this field list non-exhaustive?
#[inline]
pub fn is_field_list_non_exhaustive(&self) -> bool {
self.flags.intersects(VariantFlags::IS_FIELD_LIST_NON_EXHAUSTIVE)
}
/// Was this variant obtained as part of recovering from a syntactic error?
#[inline]
pub fn is_recovered(&self) -> bool {
self.flags.intersects(VariantFlags::IS_RECOVERED)
}
/// Does this variant contains unnamed fields
#[inline]
pub fn has_unnamed_fields(&self) -> bool {
self.flags.intersects(VariantFlags::HAS_UNNAMED_FIELDS)
}
/// Computes the `Ident` of this variant by looking up the `Span`
pub fn ident(&self, tcx: TyCtxt<'_>) -> Ident {
Ident::new(self.name, tcx.def_ident_span(self.def_id).unwrap())
}
#[inline]
pub fn ctor_kind(&self) -> Option<CtorKind> {
self.ctor.map(|(kind, _)| kind)
}
#[inline]
pub fn ctor_def_id(&self) -> Option<DefId> {
self.ctor.map(|(_, def_id)| def_id)
}
/// Returns the one field in this variant.
///
/// `panic!`s if there are no fields or multiple fields.
#[inline]
pub fn single_field(&self) -> &FieldDef {
assert!(self.fields.len() == 1);
&self.fields[FieldIdx::ZERO]
}
/// Returns the last field in this variant, if present.
#[inline]
pub fn tail_opt(&self) -> Option<&FieldDef> {
self.fields.raw.last()
}
/// Returns the last field in this variant.
///
/// # Panics
///
/// Panics, if the variant has no fields.
#[inline]
pub fn tail(&self) -> &FieldDef {
self.tail_opt().expect("expected unsized ADT to have a tail field")
}
}
impl PartialEq for VariantDef {
#[inline]
fn eq(&self, other: &Self) -> bool {
// There should be only one `VariantDef` for each `def_id`, therefore
// it is fine to implement `PartialEq` only based on `def_id`.
//
// Below, we exhaustively destructure `self` and `other` so that if the
// definition of `VariantDef` changes, a compile-error will be produced,
// reminding us to revisit this assumption.
let Self { def_id: lhs_def_id, ctor: _, name: _, discr: _, fields: _, flags: _ } = &self;
let Self { def_id: rhs_def_id, ctor: _, name: _, discr: _, fields: _, flags: _ } = other;
let res = lhs_def_id == rhs_def_id;
// Double check that implicit assumption detailed above.
if cfg!(debug_assertions) && res {
let deep = self.ctor == other.ctor
&& self.name == other.name
&& self.discr == other.discr
&& self.fields == other.fields
&& self.flags == other.flags;
assert!(deep, "VariantDef for the same def-id has differing data");
}
res
}
}
impl Eq for VariantDef {}
impl Hash for VariantDef {
#[inline]
fn hash<H: Hasher>(&self, s: &mut H) {
// There should be only one `VariantDef` for each `def_id`, therefore
// it is fine to implement `Hash` only based on `def_id`.
//
// Below, we exhaustively destructure `self` so that if the definition
// of `VariantDef` changes, a compile-error will be produced, reminding
// us to revisit this assumption.
let Self { def_id, ctor: _, name: _, discr: _, fields: _, flags: _ } = &self;
def_id.hash(s)
}
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
pub enum VariantDiscr {
/// Explicit value for this variant, i.e., `X = 123`.
/// The `DefId` corresponds to the embedded constant.
Explicit(DefId),
/// The previous variant's discriminant plus one.
/// For efficiency reasons, the distance from the
/// last `Explicit` discriminant is being stored,
/// or `0` for the first variant, if it has none.
Relative(u32),
}
#[derive(Debug, HashStable, TyEncodable, TyDecodable)]
pub struct FieldDef {
pub did: DefId,
pub name: Symbol,
pub vis: Visibility<DefId>,
}
impl PartialEq for FieldDef {
#[inline]
fn eq(&self, other: &Self) -> bool {
// There should be only one `FieldDef` for each `did`, therefore it is
// fine to implement `PartialEq` only based on `did`.
//
// Below, we exhaustively destructure `self` so that if the definition
// of `FieldDef` changes, a compile-error will be produced, reminding
// us to revisit this assumption.
let Self { did: lhs_did, name: _, vis: _ } = &self;
let Self { did: rhs_did, name: _, vis: _ } = other;
let res = lhs_did == rhs_did;
// Double check that implicit assumption detailed above.
if cfg!(debug_assertions) && res {
let deep = self.name == other.name && self.vis == other.vis;
assert!(deep, "FieldDef for the same def-id has differing data");
}
res
}
}
impl Eq for FieldDef {}
impl Hash for FieldDef {
#[inline]
fn hash<H: Hasher>(&self, s: &mut H) {
// There should be only one `FieldDef` for each `did`, therefore it is
// fine to implement `Hash` only based on `did`.
//
// Below, we exhaustively destructure `self` so that if the definition
// of `FieldDef` changes, a compile-error will be produced, reminding
// us to revisit this assumption.
let Self { did, name: _, vis: _ } = &self;
did.hash(s)
}
}
impl<'tcx> FieldDef {
/// Returns the type of this field. The resulting type is not normalized. The `arg` is
/// typically obtained via the second field of [`TyKind::Adt`].
pub fn ty(&self, tcx: TyCtxt<'tcx>, arg: GenericArgsRef<'tcx>) -> Ty<'tcx> {
tcx.type_of(self.did).instantiate(tcx, arg)
}
/// Computes the `Ident` of this variant by looking up the `Span`
pub fn ident(&self, tcx: TyCtxt<'_>) -> Ident {
Ident::new(self.name, tcx.def_ident_span(self.did).unwrap())
}
/// Returns whether the field is unnamed
pub fn is_unnamed(&self) -> bool {
self.name == rustc_span::symbol::kw::Underscore
}
}
#[derive(Debug, PartialEq, Eq)]
pub enum ImplOverlapKind {
/// These impls are always allowed to overlap.
Permitted {
/// Whether or not the impl is permitted due to the trait being a `#[marker]` trait
marker: bool,
},
/// These impls are allowed to overlap, but that raises an
/// issue #33140 future-compatibility warning (tracked in #56484).
///
/// Some background: in Rust 1.0, the trait-object types `Send + Sync` (today's
/// `dyn Send + Sync`) and `Sync + Send` (now `dyn Sync + Send`) were different.
///
/// The widely-used version 0.1.0 of the crate `traitobject` had accidentally relied on
/// that difference, doing what reduces to the following set of impls:
///
/// ```compile_fail,(E0119)
/// trait Trait {}
/// impl Trait for dyn Send + Sync {}
/// impl Trait for dyn Sync + Send {}
/// ```
///
/// Obviously, once we made these types be identical, that code causes a coherence
/// error and a fairly big headache for us. However, luckily for us, the trait
/// `Trait` used in this case is basically a marker trait, and therefore having
/// overlapping impls for it is sound.
///
/// To handle this, we basically regard the trait as a marker trait, with an additional
/// future-compatibility warning. To avoid accidentally "stabilizing" this feature,
/// it has the following restrictions:
///
/// 1. The trait must indeed be a marker-like trait (i.e., no items), and must be
/// positive impls.
/// 2. The trait-ref of both impls must be equal.
/// 3. The trait-ref of both impls must be a trait object type consisting only of
/// marker traits.
/// 4. Neither of the impls can have any where-clauses.
///
/// Once `traitobject` 0.1.0 is no longer an active concern, this hack can be removed.
FutureCompatOrderDepTraitObjects,
}
/// Useful source information about where a desugared associated type for an
/// RPITIT originated from.
#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Encodable, Decodable, HashStable)]
pub enum ImplTraitInTraitData {
Trait { fn_def_id: DefId, opaque_def_id: DefId },
Impl { fn_def_id: DefId },
}
impl<'tcx> TyCtxt<'tcx> {
pub fn typeck_body(self, body: hir::BodyId) -> &'tcx TypeckResults<'tcx> {
self.typeck(self.hir().body_owner_def_id(body))
}
pub fn provided_trait_methods(self, id: DefId) -> impl 'tcx + Iterator<Item = &'tcx AssocItem> {
self.associated_items(id)
.in_definition_order()
.filter(move |item| item.kind == AssocKind::Fn && item.defaultness(self).has_value())
}
pub fn repr_options_of_def(self, did: LocalDefId) -> ReprOptions {
let mut flags = ReprFlags::empty();
let mut size = None;
let mut max_align: Option<Align> = None;
let mut min_pack: Option<Align> = None;
// Generate a deterministically-derived seed from the item's path hash
// to allow for cross-crate compilation to actually work
let mut field_shuffle_seed =
self.def_path_hash(did.to_def_id()).0.to_smaller_hash().as_u64();
// If the user defined a custom seed for layout randomization, xor the item's
// path hash with the user defined seed, this will allowing determinism while
// still allowing users to further randomize layout generation for e.g. fuzzing
if let Some(user_seed) = self.sess.opts.unstable_opts.layout_seed {
field_shuffle_seed ^= user_seed;
}
for attr in self.get_attrs(did, sym::repr) {
for r in attr::parse_repr_attr(self.sess, attr) {
flags.insert(match r {
attr::ReprRust => ReprFlags::empty(),
attr::ReprC => ReprFlags::IS_C,
attr::ReprPacked(pack) => {
min_pack = Some(if let Some(min_pack) = min_pack {
min_pack.min(pack)
} else {
pack
});
ReprFlags::empty()
}
attr::ReprTransparent => ReprFlags::IS_TRANSPARENT,
attr::ReprSimd => ReprFlags::IS_SIMD,
attr::ReprInt(i) => {
size = Some(match i {
attr::IntType::SignedInt(x) => match x {
ast::IntTy::Isize => IntegerType::Pointer(true),
ast::IntTy::I8 => IntegerType::Fixed(Integer::I8, true),
ast::IntTy::I16 => IntegerType::Fixed(Integer::I16, true),
ast::IntTy::I32 => IntegerType::Fixed(Integer::I32, true),
ast::IntTy::I64 => IntegerType::Fixed(Integer::I64, true),
ast::IntTy::I128 => IntegerType::Fixed(Integer::I128, true),
},
attr::IntType::UnsignedInt(x) => match x {
ast::UintTy::Usize => IntegerType::Pointer(false),
ast::UintTy::U8 => IntegerType::Fixed(Integer::I8, false),
ast::UintTy::U16 => IntegerType::Fixed(Integer::I16, false),
ast::UintTy::U32 => IntegerType::Fixed(Integer::I32, false),
ast::UintTy::U64 => IntegerType::Fixed(Integer::I64, false),
ast::UintTy::U128 => IntegerType::Fixed(Integer::I128, false),
},
});
ReprFlags::empty()
}
attr::ReprAlign(align) => {
max_align = max_align.max(Some(align));
ReprFlags::empty()
}
});
}
}
// If `-Z randomize-layout` was enabled for the type definition then we can
// consider performing layout randomization
if self.sess.opts.unstable_opts.randomize_layout {
flags.insert(ReprFlags::RANDOMIZE_LAYOUT);
}
// This is here instead of layout because the choice must make it into metadata.
if !self.consider_optimizing(|| format!("Reorder fields of {:?}", self.def_path_str(did))) {
flags.insert(ReprFlags::IS_LINEAR);
}
ReprOptions { int: size, align: max_align, pack: min_pack, flags, field_shuffle_seed }
}
/// Look up the name of a definition across crates. This does not look at HIR.
pub fn opt_item_name(self, def_id: DefId) -> Option<Symbol> {
if let Some(cnum) = def_id.as_crate_root() {
Some(self.crate_name(cnum))
} else {
let def_key = self.def_key(def_id);
match def_key.disambiguated_data.data {
// The name of a constructor is that of its parent.
rustc_hir::definitions::DefPathData::Ctor => self
.opt_item_name(DefId { krate: def_id.krate, index: def_key.parent.unwrap() }),
_ => def_key.get_opt_name(),
}
}
}
/// Look up the name of a definition across crates. This does not look at HIR.
///
/// This method will ICE if the corresponding item does not have a name. In these cases, use
/// [`opt_item_name`] instead.
///
/// [`opt_item_name`]: Self::opt_item_name
pub fn item_name(self, id: DefId) -> Symbol {
self.opt_item_name(id).unwrap_or_else(|| {
bug!("item_name: no name for {:?}", self.def_path(id));
})
}
/// Look up the name and span of a definition.
///
/// See [`item_name`][Self::item_name] for more information.
pub fn opt_item_ident(self, def_id: DefId) -> Option<Ident> {
let def = self.opt_item_name(def_id)?;
let span = self
.def_ident_span(def_id)
.unwrap_or_else(|| bug!("missing ident span for {def_id:?}"));
Some(Ident::new(def, span))
}
pub fn opt_associated_item(self, def_id: DefId) -> Option<AssocItem> {
if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {
Some(self.associated_item(def_id))
} else {
None
}
}
/// If the def-id is an associated type that was desugared from a
/// return-position `impl Trait` from a trait, then provide the source info
/// about where that RPITIT came from.
pub fn opt_rpitit_info(self, def_id: DefId) -> Option<ImplTraitInTraitData> {
if let DefKind::AssocTy = self.def_kind(def_id) {
self.associated_item(def_id).opt_rpitit_info
} else {
None
}
}
pub fn find_field_index(self, ident: Ident, variant: &VariantDef) -> Option<FieldIdx> {
variant.fields.iter_enumerated().find_map(|(i, field)| {
self.hygienic_eq(ident, field.ident(self), variant.def_id).then_some(i)
})
}
/// Returns `true` if the impls are the same polarity and the trait either
/// has no items or is annotated `#[marker]` and prevents item overrides.
#[instrument(level = "debug", skip(self), ret)]
pub fn impls_are_allowed_to_overlap(
self,
def_id1: DefId,
def_id2: DefId,
) -> Option<ImplOverlapKind> {
let impl1 = self.impl_trait_header(def_id1).unwrap();
let impl2 = self.impl_trait_header(def_id2).unwrap();
let trait_ref1 = impl1.trait_ref.skip_binder();
let trait_ref2 = impl2.trait_ref.skip_binder();
// If either trait impl references an error, they're allowed to overlap,
// as one of them essentially doesn't exist.
if trait_ref1.references_error() || trait_ref2.references_error() {
return Some(ImplOverlapKind::Permitted { marker: false });
}
match (impl1.polarity, impl2.polarity) {
(ImplPolarity::Reservation, _) | (_, ImplPolarity::Reservation) => {
// `#[rustc_reservation_impl]` impls don't overlap with anything
return Some(ImplOverlapKind::Permitted { marker: false });
}
(ImplPolarity::Positive, ImplPolarity::Negative)
| (ImplPolarity::Negative, ImplPolarity::Positive) => {
// `impl AutoTrait for Type` + `impl !AutoTrait for Type`
return None;
}
(ImplPolarity::Positive, ImplPolarity::Positive)
| (ImplPolarity::Negative, ImplPolarity::Negative) => {}
};
let is_marker_impl = |trait_ref: TraitRef<'_>| self.trait_def(trait_ref.def_id).is_marker;
let is_marker_overlap = is_marker_impl(trait_ref1) && is_marker_impl(trait_ref2);
if is_marker_overlap {
return Some(ImplOverlapKind::Permitted { marker: true });
}
if let Some(self_ty1) =
self.self_ty_of_trait_impl_enabling_order_dep_trait_object_hack(def_id1)
&& let Some(self_ty2) =
self.self_ty_of_trait_impl_enabling_order_dep_trait_object_hack(def_id2)
{
if self_ty1 == self_ty2 {
return Some(ImplOverlapKind::FutureCompatOrderDepTraitObjects);
} else {
debug!("found {self_ty1:?} != {self_ty2:?}");
}
}
None
}
/// Returns `ty::VariantDef` if `res` refers to a struct,
/// or variant or their constructors, panics otherwise.
pub fn expect_variant_res(self, res: Res) -> &'tcx VariantDef {
match res {
Res::Def(DefKind::Variant, did) => {
let enum_did = self.parent(did);
self.adt_def(enum_did).variant_with_id(did)
}
Res::Def(DefKind::Struct | DefKind::Union, did) => self.adt_def(did).non_enum_variant(),
Res::Def(DefKind::Ctor(CtorOf::Variant, ..), variant_ctor_did) => {
let variant_did = self.parent(variant_ctor_did);
let enum_did = self.parent(variant_did);
self.adt_def(enum_did).variant_with_ctor_id(variant_ctor_did)
}
Res::Def(DefKind::Ctor(CtorOf::Struct, ..), ctor_did) => {
let struct_did = self.parent(ctor_did);
self.adt_def(struct_did).non_enum_variant()
}
_ => bug!("expect_variant_res used with unexpected res {:?}", res),
}
}
/// Returns the possibly-auto-generated MIR of a [`ty::InstanceDef`].
#[instrument(skip(self), level = "debug")]
pub fn instance_mir(self, instance: ty::InstanceDef<'tcx>) -> &'tcx Body<'tcx> {
match instance {
ty::InstanceDef::Item(def) => {
debug!("calling def_kind on def: {:?}", def);
let def_kind = self.def_kind(def);
debug!("returned from def_kind: {:?}", def_kind);
match def_kind {
DefKind::Const
| DefKind::Static { .. }
| DefKind::AssocConst
| DefKind::Ctor(..)
| DefKind::AnonConst
| DefKind::InlineConst => self.mir_for_ctfe(def),
// If the caller wants `mir_for_ctfe` of a function they should not be using
// `instance_mir`, so we'll assume const fn also wants the optimized version.
_ => self.optimized_mir(def),
}
}
ty::InstanceDef::VTableShim(..)
| ty::InstanceDef::ReifyShim(..)
| ty::InstanceDef::Intrinsic(..)
| ty::InstanceDef::FnPtrShim(..)
| ty::InstanceDef::Virtual(..)
| ty::InstanceDef::ClosureOnceShim { .. }
| ty::InstanceDef::ConstructCoroutineInClosureShim { .. }
| ty::InstanceDef::CoroutineKindShim { .. }
| ty::InstanceDef::DropGlue(..)
| ty::InstanceDef::CloneShim(..)
| ty::InstanceDef::ThreadLocalShim(..)
| ty::InstanceDef::FnPtrAddrShim(..)
| ty::InstanceDef::AsyncDropGlueCtorShim(..) => self.mir_shims(instance),
}
}
// FIXME(@lcnr): Remove this function.
pub fn get_attrs_unchecked(self, did: DefId) -> &'tcx [ast::Attribute] {
if let Some(did) = did.as_local() {
self.hir().attrs(self.local_def_id_to_hir_id(did))
} else {
self.item_attrs(did)
}
}
/// Gets all attributes with the given name.
pub fn get_attrs(
self,
did: impl Into<DefId>,
attr: Symbol,
) -> impl Iterator<Item = &'tcx ast::Attribute> {
let did: DefId = did.into();
let filter_fn = move |a: &&ast::Attribute| a.has_name(attr);
if let Some(did) = did.as_local() {
self.hir().attrs(self.local_def_id_to_hir_id(did)).iter().filter(filter_fn)
} else {
debug_assert!(rustc_feature::encode_cross_crate(attr));
self.item_attrs(did).iter().filter(filter_fn)
}
}
pub fn get_attrs_by_path<'attr>(
self,
did: DefId,
attr: &'attr [Symbol],
) -> impl Iterator<Item = &'tcx ast::Attribute> + 'attr
where
'tcx: 'attr,
{
let filter_fn = move |a: &&ast::Attribute| a.path_matches(attr);
if let Some(did) = did.as_local() {
self.hir().attrs(self.local_def_id_to_hir_id(did)).iter().filter(filter_fn)
} else {
self.item_attrs(did).iter().filter(filter_fn)
}
}
pub fn get_attr(self, did: impl Into<DefId>, attr: Symbol) -> Option<&'tcx ast::Attribute> {
if cfg!(debug_assertions) && !rustc_feature::is_valid_for_get_attr(attr) {
let did: DefId = did.into();
bug!("get_attr: unexpected called with DefId `{:?}`, attr `{:?}`", did, attr);
} else {
self.get_attrs(did, attr).next()
}
}
/// Determines whether an item is annotated with an attribute.
pub fn has_attr(self, did: impl Into<DefId>, attr: Symbol) -> bool {
self.get_attrs(did, attr).next().is_some()
}
/// Returns `true` if this is an `auto trait`.
pub fn trait_is_auto(self, trait_def_id: DefId) -> bool {
self.trait_def(trait_def_id).has_auto_impl
}
/// Returns `true` if this is coinductive, either because it is
/// an auto trait or because it has the `#[rustc_coinductive]` attribute.
pub fn trait_is_coinductive(self, trait_def_id: DefId) -> bool {
self.trait_def(trait_def_id).is_coinductive
}
/// Returns `true` if this is a trait alias.
pub fn trait_is_alias(self, trait_def_id: DefId) -> bool {
self.def_kind(trait_def_id) == DefKind::TraitAlias
}
/// Returns layout of a coroutine. Layout might be unavailable if the
/// coroutine is tainted by errors.
///
/// Takes `coroutine_kind` which can be acquired from the `CoroutineArgs::kind_ty`,
/// e.g. `args.as_coroutine().kind_ty()`.
pub fn coroutine_layout(
self,
def_id: DefId,
coroutine_kind_ty: Ty<'tcx>,
) -> Option<&'tcx CoroutineLayout<'tcx>> {
let mir = self.optimized_mir(def_id);
// Regular coroutine
if coroutine_kind_ty.is_unit() {
mir.coroutine_layout_raw()
} else {
// If we have a `Coroutine` that comes from an coroutine-closure,
// then it may be a by-move or by-ref body.
let ty::Coroutine(_, identity_args) =
*self.type_of(def_id).instantiate_identity().kind()
else {
unreachable!();
};
let identity_kind_ty = identity_args.as_coroutine().kind_ty();
// If the types differ, then we must be getting the by-move body of
// a by-ref coroutine.
if identity_kind_ty == coroutine_kind_ty {
mir.coroutine_layout_raw()
} else {
assert_matches!(coroutine_kind_ty.to_opt_closure_kind(), Some(ClosureKind::FnOnce));
assert_matches!(
identity_kind_ty.to_opt_closure_kind(),
Some(ClosureKind::Fn | ClosureKind::FnMut)
);
mir.coroutine_by_move_body().unwrap().coroutine_layout_raw()
}
}
}
/// Given the `DefId` of an impl, returns the `DefId` of the trait it implements.
/// If it implements no trait, returns `None`.
pub fn trait_id_of_impl(self, def_id: DefId) -> Option<DefId> {
self.impl_trait_ref(def_id).map(|tr| tr.skip_binder().def_id)
}
/// If the given `DefId` describes an item belonging to a trait,
/// returns the `DefId` of the trait that the trait item belongs to;
/// otherwise, returns `None`.
pub fn trait_of_item(self, def_id: DefId) -> Option<DefId> {
if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {
let parent = self.parent(def_id);
if let DefKind::Trait | DefKind::TraitAlias = self.def_kind(parent) {
return Some(parent);
}
}
None
}
/// If the given `DefId` describes a method belonging to an impl, returns the
/// `DefId` of the impl that the method belongs to; otherwise, returns `None`.
pub fn impl_of_method(self, def_id: DefId) -> Option<DefId> {
if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {
let parent = self.parent(def_id);
if let DefKind::Impl { .. } = self.def_kind(parent) {
return Some(parent);
}
}
None
}
/// Check if the given `DefId` is `#\[automatically_derived\]`, *and*
/// whether it was produced by expanding a builtin derive macro.
pub fn is_builtin_derived(self, def_id: DefId) -> bool {
if self.is_automatically_derived(def_id)
&& let Some(def_id) = def_id.as_local()
&& let outer = self.def_span(def_id).ctxt().outer_expn_data()
&& matches!(outer.kind, ExpnKind::Macro(MacroKind::Derive, _))
&& self.has_attr(outer.macro_def_id.unwrap(), sym::rustc_builtin_macro)
{
true
} else {
false
}
}
/// Check if the given `DefId` is `#\[automatically_derived\]`.
pub fn is_automatically_derived(self, def_id: DefId) -> bool {
self.has_attr(def_id, sym::automatically_derived)
}
/// Looks up the span of `impl_did` if the impl is local; otherwise returns `Err`
/// with the name of the crate containing the impl.
pub fn span_of_impl(self, impl_def_id: DefId) -> Result<Span, Symbol> {
if let Some(impl_def_id) = impl_def_id.as_local() {
Ok(self.def_span(impl_def_id))
} else {
Err(self.crate_name(impl_def_id.krate))
}
}
/// Hygienically compares a use-site name (`use_name`) for a field or an associated item with
/// its supposed definition name (`def_name`). The method also needs `DefId` of the supposed
/// definition's parent/scope to perform comparison.
pub fn hygienic_eq(self, use_name: Ident, def_name: Ident, def_parent_def_id: DefId) -> bool {
// We could use `Ident::eq` here, but we deliberately don't. The name
// comparison fails frequently, and we want to avoid the expensive
// `normalize_to_macros_2_0()` calls required for the span comparison whenever possible.
use_name.name == def_name.name
&& use_name
.span
.ctxt()
.hygienic_eq(def_name.span.ctxt(), self.expn_that_defined(def_parent_def_id))
}
pub fn adjust_ident(self, mut ident: Ident, scope: DefId) -> Ident {
ident.span.normalize_to_macros_2_0_and_adjust(self.expn_that_defined(scope));
ident
}
// FIXME(vincenzopalazzo): move the HirId to a LocalDefId
pub fn adjust_ident_and_get_scope(
self,
mut ident: Ident,
scope: DefId,
block: hir::HirId,
) -> (Ident, DefId) {
let scope = ident
.span
.normalize_to_macros_2_0_and_adjust(self.expn_that_defined(scope))
.and_then(|actual_expansion| actual_expansion.expn_data().parent_module)
.unwrap_or_else(|| self.parent_module(block).to_def_id());
(ident, scope)
}
#[inline]
pub fn is_const_fn_raw(self, def_id: DefId) -> bool {
matches!(
self.def_kind(def_id),
DefKind::Fn | DefKind::AssocFn | DefKind::Ctor(..) | DefKind::Closure
) && self.constness(def_id) == hir::Constness::Const
}
#[inline]
pub fn is_const_default_method(self, def_id: DefId) -> bool {
matches!(self.trait_of_item(def_id), Some(trait_id) if self.has_attr(trait_id, sym::const_trait))
}
pub fn impl_method_has_trait_impl_trait_tys(self, def_id: DefId) -> bool {
if self.def_kind(def_id) != DefKind::AssocFn {
return false;
}
let Some(item) = self.opt_associated_item(def_id) else {
return false;
};
if item.container != ty::AssocItemContainer::ImplContainer {
return false;
}
let Some(trait_item_def_id) = item.trait_item_def_id else {
return false;
};
return !self
.associated_types_for_impl_traits_in_associated_fn(trait_item_def_id)
.is_empty();
}
}
pub fn int_ty(ity: ast::IntTy) -> IntTy {
match ity {
ast::IntTy::Isize => IntTy::Isize,
ast::IntTy::I8 => IntTy::I8,
ast::IntTy::I16 => IntTy::I16,
ast::IntTy::I32 => IntTy::I32,
ast::IntTy::I64 => IntTy::I64,
ast::IntTy::I128 => IntTy::I128,
}
}
pub fn uint_ty(uty: ast::UintTy) -> UintTy {
match uty {
ast::UintTy::Usize => UintTy::Usize,
ast::UintTy::U8 => UintTy::U8,
ast::UintTy::U16 => UintTy::U16,
ast::UintTy::U32 => UintTy::U32,
ast::UintTy::U64 => UintTy::U64,
ast::UintTy::U128 => UintTy::U128,
}
}
pub fn float_ty(fty: ast::FloatTy) -> FloatTy {
match fty {
ast::FloatTy::F16 => FloatTy::F16,
ast::FloatTy::F32 => FloatTy::F32,
ast::FloatTy::F64 => FloatTy::F64,
ast::FloatTy::F128 => FloatTy::F128,
}
}
pub fn ast_int_ty(ity: IntTy) -> ast::IntTy {
match ity {
IntTy::Isize => ast::IntTy::Isize,
IntTy::I8 => ast::IntTy::I8,
IntTy::I16 => ast::IntTy::I16,
IntTy::I32 => ast::IntTy::I32,
IntTy::I64 => ast::IntTy::I64,
IntTy::I128 => ast::IntTy::I128,
}
}
pub fn ast_uint_ty(uty: UintTy) -> ast::UintTy {
match uty {
UintTy::Usize => ast::UintTy::Usize,
UintTy::U8 => ast::UintTy::U8,
UintTy::U16 => ast::UintTy::U16,
UintTy::U32 => ast::UintTy::U32,
UintTy::U64 => ast::UintTy::U64,
UintTy::U128 => ast::UintTy::U128,
}
}
pub fn provide(providers: &mut Providers) {
closure::provide(providers);
context::provide(providers);
erase_regions::provide(providers);
inhabitedness::provide(providers);
util::provide(providers);
print::provide(providers);
super::util::bug::provide(providers);
super::middle::provide(providers);
*providers = Providers {
trait_impls_of: trait_def::trait_impls_of_provider,
incoherent_impls: trait_def::incoherent_impls_provider,
const_param_default: consts::const_param_default,
vtable_allocation: vtable::vtable_allocation_provider,
..*providers
};
}
/// A map for the local crate mapping each type to a vector of its
/// inherent impls. This is not meant to be used outside of coherence;
/// rather, you should request the vector for a specific type via
/// `tcx.inherent_impls(def_id)` so as to minimize your dependencies
/// (constructing this map requires touching the entire crate).
#[derive(Clone, Debug, Default, HashStable)]
pub struct CrateInherentImpls {
pub inherent_impls: LocalDefIdMap<Vec<DefId>>,
pub incoherent_impls: UnordMap<SimplifiedType, Vec<LocalDefId>>,
}
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, HashStable)]
pub struct SymbolName<'tcx> {
/// `&str` gives a consistent ordering, which ensures reproducible builds.
pub name: &'tcx str,
}
impl<'tcx> SymbolName<'tcx> {
pub fn new(tcx: TyCtxt<'tcx>, name: &str) -> SymbolName<'tcx> {
SymbolName { name: tcx.arena.alloc_str(name) }
}
}
impl<'tcx> fmt::Display for SymbolName<'tcx> {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(&self.name, fmt)
}
}
impl<'tcx> fmt::Debug for SymbolName<'tcx> {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt::Display::fmt(&self.name, fmt)
}
}
#[derive(Debug, Default, Copy, Clone)]
pub struct InferVarInfo {
/// This is true if we identified that this Ty (`?T`) is found in a `?T: Foo`
/// obligation, where:
///
/// * `Foo` is not `Sized`
/// * `(): Foo` may be satisfied
pub self_in_trait: bool,
/// This is true if we identified that this Ty (`?T`) is found in a `<_ as
/// _>::AssocType = ?T`
pub output: bool,
}
/// The constituent parts of a type level constant of kind ADT or array.
#[derive(Copy, Clone, Debug, HashStable)]
pub struct DestructuredConst<'tcx> {
pub variant: Option<VariantIdx>,
pub fields: &'tcx [ty::Const<'tcx>],
}
// Some types are used a lot. Make sure they don't unintentionally get bigger.
#[cfg(target_pointer_width = "64")]
mod size_asserts {
use super::*;
use rustc_data_structures::static_assert_size;
// tidy-alphabetical-start
static_assert_size!(PredicateKind<'_>, 32);
static_assert_size!(WithCachedTypeInfo<TyKind<'_>>, 56);
// tidy-alphabetical-end
}