1 //! Type context book-keeping.
3 #![allow(rustc::usage_of_ty_tykind)]
5 use crate::arena::Arena;
6 use crate::dep_graph::{DepGraph, DepKindStruct};
7 use crate::infer::canonical::{CanonicalVarInfo, CanonicalVarInfos};
8 use crate::lint::struct_lint_level;
9 use crate::middle::codegen_fn_attrs::CodegenFnAttrs;
10 use crate::middle::resolve_lifetime;
11 use crate::middle::stability;
12 use crate::mir::interpret::{self, Allocation, ConstAllocation};
14 Body, BorrowCheckResult, Field, Local, Place, PlaceElem, ProjectionKind, Promoted,
16 use crate::thir::Thir;
18 use crate::ty::query::{self, TyCtxtAt};
20 self, AdtDef, AdtDefData, AdtKind, Binder, Const, ConstData, DefIdTree, FloatTy, FloatVar,
21 FloatVid, GenericParamDefKind, ImplPolarity, InferTy, IntTy, IntVar, IntVid, List, ParamConst,
22 ParamTy, PolyExistentialPredicate, PolyFnSig, Predicate, PredicateKind, Region, RegionKind,
23 ReprOptions, TraitObjectVisitor, Ty, TyKind, TyVar, TyVid, TypeAndMut, TypeckResults, UintTy,
26 use crate::ty::{GenericArg, InternalSubsts, SubstsRef};
28 use rustc_data_structures::fingerprint::Fingerprint;
29 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
30 use rustc_data_structures::intern::Interned;
31 use rustc_data_structures::memmap::Mmap;
32 use rustc_data_structures::profiling::SelfProfilerRef;
33 use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
34 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
35 use rustc_data_structures::steal::Steal;
36 use rustc_data_structures::sync::{self, Lock, Lrc, ReadGuard, WorkerLocal};
38 DecorateLint, DiagnosticBuilder, DiagnosticMessage, ErrorGuaranteed, MultiSpan,
41 use rustc_hir::def::DefKind;
42 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
43 use rustc_hir::definitions::Definitions;
44 use rustc_hir::intravisit::Visitor;
45 use rustc_hir::lang_items::LangItem;
47 Constness, ExprKind, HirId, ImplItemKind, ItemKind, Node, TraitCandidate, TraitItemKind,
49 use rustc_index::vec::IndexVec;
50 use rustc_macros::HashStable;
51 use rustc_query_system::dep_graph::DepNodeIndex;
52 use rustc_query_system::ich::StableHashingContext;
53 use rustc_serialize::opaque::{FileEncodeResult, FileEncoder};
54 use rustc_session::config::CrateType;
55 use rustc_session::cstore::{CrateStoreDyn, Untracked};
56 use rustc_session::lint::Lint;
57 use rustc_session::Limit;
58 use rustc_session::Session;
59 use rustc_span::def_id::{DefPathHash, StableCrateId};
60 use rustc_span::source_map::SourceMap;
61 use rustc_span::symbol::{kw, sym, Ident, Symbol};
62 use rustc_span::{Span, DUMMY_SP};
63 use rustc_target::abi::{Layout, LayoutS, TargetDataLayout, VariantIdx};
64 use rustc_target::spec::abi;
65 use rustc_type_ir::sty::TyKind::*;
66 use rustc_type_ir::WithCachedTypeInfo;
67 use rustc_type_ir::{DynKind, InternAs, InternIteratorElement, Interner, TypeFlags};
70 use std::borrow::Borrow;
71 use std::cmp::Ordering;
73 use std::hash::{Hash, Hasher};
76 use std::ops::{Bound, Deref};
78 pub trait OnDiskCache<'tcx>: rustc_data_structures::sync::Sync {
79 /// Creates a new `OnDiskCache` instance from the serialized data in `data`.
80 fn new(sess: &'tcx Session, data: Mmap, start_pos: usize) -> Self
84 fn new_empty(source_map: &'tcx SourceMap) -> Self
88 fn drop_serialized_data(&self, tcx: TyCtxt<'tcx>);
90 fn serialize(&self, tcx: TyCtxt<'tcx>, encoder: FileEncoder) -> FileEncodeResult;
93 #[allow(rustc::usage_of_ty_tykind)]
94 impl<'tcx> Interner for TyCtxt<'tcx> {
95 type AdtDef = ty::AdtDef<'tcx>;
96 type SubstsRef = ty::SubstsRef<'tcx>;
99 type Const = ty::Const<'tcx>;
100 type Region = Region<'tcx>;
101 type TypeAndMut = TypeAndMut<'tcx>;
102 type Mutability = hir::Mutability;
103 type Movability = hir::Movability;
104 type PolyFnSig = PolyFnSig<'tcx>;
105 type ListBinderExistentialPredicate = &'tcx List<PolyExistentialPredicate<'tcx>>;
106 type BinderListTy = Binder<'tcx, &'tcx List<Ty<'tcx>>>;
107 type ListTy = &'tcx List<Ty<'tcx>>;
108 type AliasTy = ty::AliasTy<'tcx>;
109 type ParamTy = ParamTy;
110 type BoundTy = ty::BoundTy;
111 type PlaceholderType = ty::PlaceholderType;
112 type InferTy = InferTy;
113 type ErrorGuaranteed = ErrorGuaranteed;
114 type PredicateKind = ty::PredicateKind<'tcx>;
115 type AllocId = crate::mir::interpret::AllocId;
117 type EarlyBoundRegion = ty::EarlyBoundRegion;
118 type BoundRegion = ty::BoundRegion;
119 type FreeRegion = ty::FreeRegion;
120 type RegionVid = ty::RegionVid;
121 type PlaceholderRegion = ty::PlaceholderRegion;
124 type InternedSet<'tcx, T> = ShardedHashMap<InternedInSet<'tcx, T>, ()>;
126 pub struct CtxtInterners<'tcx> {
127 /// The arena that types, regions, etc. are allocated from.
128 arena: &'tcx WorkerLocal<Arena<'tcx>>,
130 // Specifically use a speedy hash algorithm for these hash sets, since
131 // they're accessed quite often.
132 type_: InternedSet<'tcx, WithCachedTypeInfo<TyKind<'tcx>>>,
133 const_lists: InternedSet<'tcx, List<ty::Const<'tcx>>>,
134 substs: InternedSet<'tcx, InternalSubsts<'tcx>>,
135 canonical_var_infos: InternedSet<'tcx, List<CanonicalVarInfo<'tcx>>>,
136 region: InternedSet<'tcx, RegionKind<'tcx>>,
137 poly_existential_predicates: InternedSet<'tcx, List<PolyExistentialPredicate<'tcx>>>,
138 predicate: InternedSet<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>,
139 predicates: InternedSet<'tcx, List<Predicate<'tcx>>>,
140 projs: InternedSet<'tcx, List<ProjectionKind>>,
141 place_elems: InternedSet<'tcx, List<PlaceElem<'tcx>>>,
142 const_: InternedSet<'tcx, ConstData<'tcx>>,
143 const_allocation: InternedSet<'tcx, Allocation>,
144 bound_variable_kinds: InternedSet<'tcx, List<ty::BoundVariableKind>>,
145 layout: InternedSet<'tcx, LayoutS<VariantIdx>>,
146 adt_def: InternedSet<'tcx, AdtDefData>,
149 impl<'tcx> CtxtInterners<'tcx> {
150 fn new(arena: &'tcx WorkerLocal<Arena<'tcx>>) -> CtxtInterners<'tcx> {
153 type_: Default::default(),
154 const_lists: Default::default(),
155 substs: Default::default(),
156 region: Default::default(),
157 poly_existential_predicates: Default::default(),
158 canonical_var_infos: Default::default(),
159 predicate: Default::default(),
160 predicates: Default::default(),
161 projs: Default::default(),
162 place_elems: Default::default(),
163 const_: Default::default(),
164 const_allocation: Default::default(),
165 bound_variable_kinds: Default::default(),
166 layout: Default::default(),
167 adt_def: Default::default(),
172 #[allow(rustc::usage_of_ty_tykind)]
174 fn intern_ty(&self, kind: TyKind<'tcx>, sess: &Session, untracked: &Untracked) -> Ty<'tcx> {
175 Ty(Interned::new_unchecked(
177 .intern(kind, |kind| {
178 let flags = super::flags::FlagComputation::for_kind(&kind);
179 let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
181 InternedInSet(self.arena.alloc(WithCachedTypeInfo {
185 outer_exclusive_binder: flags.outer_exclusive_binder,
192 fn stable_hash<'a, T: HashStable<StableHashingContext<'a>>>(
194 flags: &ty::flags::FlagComputation,
196 untracked: &'a Untracked,
199 // It's impossible to hash inference variables (and will ICE), so we don't need to try to cache them.
200 // Without incremental, we rarely stable-hash types, so let's not do it proactively.
201 if flags.flags.intersects(TypeFlags::NEEDS_INFER) || sess.opts.incremental.is_none() {
204 let mut hasher = StableHasher::new();
205 let mut hcx = StableHashingContext::new(sess, untracked);
206 val.hash_stable(&mut hcx, &mut hasher);
214 kind: Binder<'tcx, PredicateKind<'tcx>>,
216 untracked: &Untracked,
217 ) -> Predicate<'tcx> {
218 Predicate(Interned::new_unchecked(
220 .intern(kind, |kind| {
221 let flags = super::flags::FlagComputation::for_predicate(kind);
223 let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
225 InternedInSet(self.arena.alloc(WithCachedTypeInfo {
229 outer_exclusive_binder: flags.outer_exclusive_binder,
237 pub struct CommonTypes<'tcx> {
257 pub self_param: Ty<'tcx>,
259 /// Dummy type used for the `Self` of a `TraitRef` created for converting
260 /// a trait object, and which gets removed in `ExistentialTraitRef`.
261 /// This type must not appear anywhere in other converted types.
262 pub trait_object_dummy_self: Ty<'tcx>,
265 pub struct CommonLifetimes<'tcx> {
267 pub re_static: Region<'tcx>,
269 /// Erased region, used outside of type inference.
270 pub re_erased: Region<'tcx>,
273 pub struct CommonConsts<'tcx> {
274 pub unit: Const<'tcx>,
277 impl<'tcx> CommonTypes<'tcx> {
279 interners: &CtxtInterners<'tcx>,
281 untracked: &Untracked,
282 ) -> CommonTypes<'tcx> {
283 let mk = |ty| interners.intern_ty(ty, sess, untracked);
286 unit: mk(Tuple(List::empty())),
290 isize: mk(Int(ty::IntTy::Isize)),
291 i8: mk(Int(ty::IntTy::I8)),
292 i16: mk(Int(ty::IntTy::I16)),
293 i32: mk(Int(ty::IntTy::I32)),
294 i64: mk(Int(ty::IntTy::I64)),
295 i128: mk(Int(ty::IntTy::I128)),
296 usize: mk(Uint(ty::UintTy::Usize)),
297 u8: mk(Uint(ty::UintTy::U8)),
298 u16: mk(Uint(ty::UintTy::U16)),
299 u32: mk(Uint(ty::UintTy::U32)),
300 u64: mk(Uint(ty::UintTy::U64)),
301 u128: mk(Uint(ty::UintTy::U128)),
302 f32: mk(Float(ty::FloatTy::F32)),
303 f64: mk(Float(ty::FloatTy::F64)),
305 self_param: mk(ty::Param(ty::ParamTy { index: 0, name: kw::SelfUpper })),
307 trait_object_dummy_self: mk(Infer(ty::FreshTy(0))),
312 impl<'tcx> CommonLifetimes<'tcx> {
313 fn new(interners: &CtxtInterners<'tcx>) -> CommonLifetimes<'tcx> {
315 Region(Interned::new_unchecked(
316 interners.region.intern(r, |r| InternedInSet(interners.arena.alloc(r))).0,
320 CommonLifetimes { re_static: mk(ty::ReStatic), re_erased: mk(ty::ReErased) }
324 impl<'tcx> CommonConsts<'tcx> {
325 fn new(interners: &CtxtInterners<'tcx>, types: &CommonTypes<'tcx>) -> CommonConsts<'tcx> {
327 Const(Interned::new_unchecked(
328 interners.const_.intern(c, |c| InternedInSet(interners.arena.alloc(c))).0,
333 unit: mk_const(ty::ConstData {
334 kind: ty::ConstKind::Value(ty::ValTree::zst()),
341 /// This struct contains information regarding the `ReFree(FreeRegion)` corresponding to a lifetime
344 pub struct FreeRegionInfo {
345 /// `LocalDefId` corresponding to FreeRegion
346 pub def_id: LocalDefId,
347 /// the bound region corresponding to FreeRegion
348 pub boundregion: ty::BoundRegionKind,
349 /// checks if bound region is in Impl Item
350 pub is_impl_item: bool,
353 /// This struct should only be created by `create_def`.
354 #[derive(Copy, Clone)]
355 pub struct TyCtxtFeed<'tcx, KEY: Copy> {
356 pub tcx: TyCtxt<'tcx>,
357 // Do not allow direct access, as downstream code must not mutate this field.
361 impl<'tcx> TyCtxt<'tcx> {
362 pub fn feed_unit_query(self) -> TyCtxtFeed<'tcx, ()> {
363 TyCtxtFeed { tcx: self, key: () }
365 pub fn feed_local_crate(self) -> TyCtxtFeed<'tcx, CrateNum> {
366 TyCtxtFeed { tcx: self, key: LOCAL_CRATE }
370 impl<'tcx, KEY: Copy> TyCtxtFeed<'tcx, KEY> {
372 pub fn key(&self) -> KEY {
377 impl<'tcx> TyCtxtFeed<'tcx, LocalDefId> {
379 pub fn def_id(&self) -> LocalDefId {
384 /// The central data structure of the compiler. It stores references
385 /// to the various **arenas** and also houses the results of the
386 /// various **compiler queries** that have been performed. See the
387 /// [rustc dev guide] for more details.
389 /// [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/ty.html
390 #[derive(Copy, Clone)]
391 #[rustc_diagnostic_item = "TyCtxt"]
392 #[rustc_pass_by_value]
393 pub struct TyCtxt<'tcx> {
394 gcx: &'tcx GlobalCtxt<'tcx>,
397 impl<'tcx> Deref for TyCtxt<'tcx> {
398 type Target = &'tcx GlobalCtxt<'tcx>;
400 fn deref(&self) -> &Self::Target {
405 pub struct GlobalCtxt<'tcx> {
406 pub arena: &'tcx WorkerLocal<Arena<'tcx>>,
407 pub hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
409 interners: CtxtInterners<'tcx>,
411 pub sess: &'tcx Session,
413 /// This only ever stores a `LintStore` but we don't want a dependency on that type here.
415 /// FIXME(Centril): consider `dyn LintStoreMarker` once
416 /// we can upcast to `Any` for some additional type safety.
417 pub lint_store: Lrc<dyn Any + sync::Sync + sync::Send>,
419 pub dep_graph: DepGraph,
421 pub prof: SelfProfilerRef,
423 /// Common types, pre-interned for your convenience.
424 pub types: CommonTypes<'tcx>,
426 /// Common lifetimes, pre-interned for your convenience.
427 pub lifetimes: CommonLifetimes<'tcx>,
429 /// Common consts, pre-interned for your convenience.
430 pub consts: CommonConsts<'tcx>,
432 untracked: Untracked,
434 /// This provides access to the incremental compilation on-disk cache for query results.
435 /// Do not access this directly. It is only meant to be used by
436 /// `DepGraph::try_mark_green()` and the query infrastructure.
437 /// This is `None` if we are not incremental compilation mode
438 pub on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
440 pub queries: &'tcx dyn query::QueryEngine<'tcx>,
441 pub query_caches: query::QueryCaches<'tcx>,
442 pub(crate) query_kinds: &'tcx [DepKindStruct<'tcx>],
444 // Internal caches for metadata decoding. No need to track deps on this.
445 pub ty_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
446 pub pred_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Predicate<'tcx>>>,
448 /// Caches the results of trait selection. This cache is used
449 /// for things that do not have to do with the parameters in scope.
450 pub selection_cache: traits::SelectionCache<'tcx>,
452 /// Caches the results of trait evaluation. This cache is used
453 /// for things that do not have to do with the parameters in scope.
454 /// Merge this with `selection_cache`?
455 pub evaluation_cache: traits::EvaluationCache<'tcx>,
457 /// Data layout specification for the current target.
458 pub data_layout: TargetDataLayout,
460 /// Stores memory for globals (statics/consts).
461 pub(crate) alloc_map: Lock<interpret::AllocMap<'tcx>>,
464 impl<'tcx> TyCtxt<'tcx> {
465 /// Expects a body and returns its codegen attributes.
467 /// Unlike `codegen_fn_attrs`, this returns `CodegenFnAttrs::EMPTY` for
469 pub fn body_codegen_attrs(self, def_id: DefId) -> &'tcx CodegenFnAttrs {
470 let def_kind = self.def_kind(def_id);
471 if def_kind.has_codegen_attrs() {
472 self.codegen_fn_attrs(def_id)
475 DefKind::AnonConst | DefKind::AssocConst | DefKind::Const | DefKind::InlineConst
477 CodegenFnAttrs::EMPTY
480 "body_codegen_fn_attrs called on unexpected definition: {:?} {:?}",
487 pub fn typeck_opt_const_arg(
489 def: ty::WithOptConstParam<LocalDefId>,
490 ) -> &'tcx TypeckResults<'tcx> {
491 if let Some(param_did) = def.const_param_did {
492 self.typeck_const_arg((def.did, param_did))
498 pub fn mir_borrowck_opt_const_arg(
500 def: ty::WithOptConstParam<LocalDefId>,
501 ) -> &'tcx BorrowCheckResult<'tcx> {
502 if let Some(param_did) = def.const_param_did {
503 self.mir_borrowck_const_arg((def.did, param_did))
505 self.mir_borrowck(def.did)
509 pub fn alloc_steal_thir(self, thir: Thir<'tcx>) -> &'tcx Steal<Thir<'tcx>> {
510 self.arena.alloc(Steal::new(thir))
513 pub fn alloc_steal_mir(self, mir: Body<'tcx>) -> &'tcx Steal<Body<'tcx>> {
514 self.arena.alloc(Steal::new(mir))
517 pub fn alloc_steal_promoted(
519 promoted: IndexVec<Promoted, Body<'tcx>>,
520 ) -> &'tcx Steal<IndexVec<Promoted, Body<'tcx>>> {
521 self.arena.alloc(Steal::new(promoted))
524 pub fn alloc_adt_def(
528 variants: IndexVec<VariantIdx, ty::VariantDef>,
530 ) -> ty::AdtDef<'tcx> {
531 self.intern_adt_def(ty::AdtDefData::new(self, did, kind, variants, repr))
534 /// Allocates a read-only byte or string literal for `mir::interpret`.
535 pub fn allocate_bytes(self, bytes: &[u8]) -> interpret::AllocId {
536 // Create an allocation that just contains these bytes.
537 let alloc = interpret::Allocation::from_bytes_byte_aligned_immutable(bytes);
538 let alloc = self.intern_const_alloc(alloc);
539 self.create_memory_alloc(alloc)
542 /// Returns a range of the start/end indices specified with the
543 /// `rustc_layout_scalar_valid_range` attribute.
544 // FIXME(eddyb) this is an awkward spot for this method, maybe move it?
545 pub fn layout_scalar_valid_range(self, def_id: DefId) -> (Bound<u128>, Bound<u128>) {
547 let Some(attr) = self.get_attr(def_id, name) else {
548 return Bound::Unbounded;
550 debug!("layout_scalar_valid_range: attr={:?}", attr);
553 ast::NestedMetaItem::Lit(ast::MetaItemLit {
554 kind: ast::LitKind::Int(a, _),
558 ) = attr.meta_item_list().as_deref()
563 .delay_span_bug(attr.span, "invalid rustc_layout_scalar_valid_range attribute");
568 get(sym::rustc_layout_scalar_valid_range_start),
569 get(sym::rustc_layout_scalar_valid_range_end),
573 pub fn lift<T: Lift<'tcx>>(self, value: T) -> Option<T::Lifted> {
574 value.lift_to_tcx(self)
577 /// Creates a type context and call the closure with a `TyCtxt` reference
578 /// to the context. The closure enforces that the type context and any interned
579 /// value (types, substs, etc.) can only be used while `ty::tls` has a valid
580 /// reference to the context, to allow formatting values that need it.
581 pub fn create_global_ctxt(
583 lint_store: Lrc<dyn Any + sync::Send + sync::Sync>,
584 arena: &'tcx WorkerLocal<Arena<'tcx>>,
585 hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
586 untracked: Untracked,
588 on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
589 queries: &'tcx dyn query::QueryEngine<'tcx>,
590 query_kinds: &'tcx [DepKindStruct<'tcx>],
591 ) -> GlobalCtxt<'tcx> {
592 let data_layout = s.target.parse_data_layout().unwrap_or_else(|err| {
595 let interners = CtxtInterners::new(arena);
596 let common_types = CommonTypes::new(&interners, s, &untracked);
597 let common_lifetimes = CommonLifetimes::new(&interners);
598 let common_consts = CommonConsts::new(&interners, &common_types);
607 prof: s.prof.clone(),
609 lifetimes: common_lifetimes,
610 consts: common_consts,
614 query_caches: query::QueryCaches::default(),
616 ty_rcache: Default::default(),
617 pred_rcache: Default::default(),
618 selection_cache: Default::default(),
619 evaluation_cache: Default::default(),
621 alloc_map: Lock::new(interpret::AllocMap::new()),
625 /// Constructs a `TyKind::Error` type with current `ErrorGuaranteed`
627 pub fn ty_error_with_guaranteed(self, reported: ErrorGuaranteed) -> Ty<'tcx> {
628 self.mk_ty(Error(reported))
631 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
633 pub fn ty_error(self) -> Ty<'tcx> {
634 self.ty_error_with_message(DUMMY_SP, "TyKind::Error constructed but no error reported")
637 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg` to
638 /// ensure it gets used.
640 pub fn ty_error_with_message<S: Into<MultiSpan>>(self, span: S, msg: &str) -> Ty<'tcx> {
641 let reported = self.sess.delay_span_bug(span, msg);
642 self.mk_ty(Error(reported))
645 /// Like [TyCtxt::ty_error] but for constants, with current `ErrorGuaranteed`
647 pub fn const_error_with_guaranteed(
650 reported: ErrorGuaranteed,
652 self.mk_const(ty::ConstKind::Error(reported), ty)
655 /// Like [TyCtxt::ty_error] but for constants.
657 pub fn const_error(self, ty: Ty<'tcx>) -> Const<'tcx> {
658 self.const_error_with_message(
661 "ty::ConstKind::Error constructed but no error reported",
665 /// Like [TyCtxt::ty_error_with_message] but for constants.
667 pub fn const_error_with_message<S: Into<MultiSpan>>(
673 let reported = self.sess.delay_span_bug(span, msg);
674 self.mk_const(ty::ConstKind::Error(reported), ty)
677 pub fn consider_optimizing<T: Fn() -> String>(self, msg: T) -> bool {
678 let cname = self.crate_name(LOCAL_CRATE);
679 self.sess.consider_optimizing(cname.as_str(), msg)
682 /// Obtain all lang items of this crate and all dependencies (recursively)
683 pub fn lang_items(self) -> &'tcx rustc_hir::lang_items::LanguageItems {
684 self.get_lang_items(())
687 /// Obtain the given diagnostic item's `DefId`. Use `is_diagnostic_item` if you just want to
688 /// compare against another `DefId`, since `is_diagnostic_item` is cheaper.
689 pub fn get_diagnostic_item(self, name: Symbol) -> Option<DefId> {
690 self.all_diagnostic_items(()).name_to_id.get(&name).copied()
693 /// Obtain the diagnostic item's name
694 pub fn get_diagnostic_name(self, id: DefId) -> Option<Symbol> {
695 self.diagnostic_items(id.krate).id_to_name.get(&id).copied()
698 /// Check whether the diagnostic item with the given `name` has the given `DefId`.
699 pub fn is_diagnostic_item(self, name: Symbol, did: DefId) -> bool {
700 self.diagnostic_items(did.krate).name_to_id.get(&name) == Some(&did)
703 /// Returns `true` if the node pointed to by `def_id` is a generator for an async construct.
704 pub fn generator_is_async(self, def_id: DefId) -> bool {
705 matches!(self.generator_kind(def_id), Some(hir::GeneratorKind::Async(_)))
708 pub fn stability(self) -> &'tcx stability::Index {
709 self.stability_index(())
712 pub fn features(self) -> &'tcx rustc_feature::Features {
713 self.features_query(())
716 pub fn def_key(self, id: DefId) -> rustc_hir::definitions::DefKey {
717 // Accessing the DefKey is ok, since it is part of DefPathHash.
718 if let Some(id) = id.as_local() {
719 self.definitions_untracked().def_key(id)
721 self.untracked.cstore.def_key(id)
725 /// Converts a `DefId` into its fully expanded `DefPath` (every
726 /// `DefId` is really just an interned `DefPath`).
728 /// Note that if `id` is not local to this crate, the result will
729 /// be a non-local `DefPath`.
730 pub fn def_path(self, id: DefId) -> rustc_hir::definitions::DefPath {
731 // Accessing the DefPath is ok, since it is part of DefPathHash.
732 if let Some(id) = id.as_local() {
733 self.definitions_untracked().def_path(id)
735 self.untracked.cstore.def_path(id)
740 pub fn def_path_hash(self, def_id: DefId) -> rustc_hir::definitions::DefPathHash {
741 // Accessing the DefPathHash is ok, it is incr. comp. stable.
742 if let Some(def_id) = def_id.as_local() {
743 self.definitions_untracked().def_path_hash(def_id)
745 self.untracked.cstore.def_path_hash(def_id)
750 pub fn stable_crate_id(self, crate_num: CrateNum) -> StableCrateId {
751 if crate_num == LOCAL_CRATE {
752 self.sess.local_stable_crate_id()
754 self.untracked.cstore.stable_crate_id(crate_num)
758 /// Maps a StableCrateId to the corresponding CrateNum. This method assumes
759 /// that the crate in question has already been loaded by the CrateStore.
761 pub fn stable_crate_id_to_crate_num(self, stable_crate_id: StableCrateId) -> CrateNum {
762 if stable_crate_id == self.sess.local_stable_crate_id() {
765 self.untracked.cstore.stable_crate_id_to_crate_num(stable_crate_id)
769 /// Converts a `DefPathHash` to its corresponding `DefId` in the current compilation
770 /// session, if it still exists. This is used during incremental compilation to
771 /// turn a deserialized `DefPathHash` into its current `DefId`.
772 pub fn def_path_hash_to_def_id(self, hash: DefPathHash, err: &mut dyn FnMut() -> !) -> DefId {
773 debug!("def_path_hash_to_def_id({:?})", hash);
775 let stable_crate_id = hash.stable_crate_id();
777 // If this is a DefPathHash from the local crate, we can look up the
778 // DefId in the tcx's `Definitions`.
779 if stable_crate_id == self.sess.local_stable_crate_id() {
780 self.untracked.definitions.read().local_def_path_hash_to_def_id(hash, err).to_def_id()
782 // If this is a DefPathHash from an upstream crate, let the CrateStore map
784 let cstore = &*self.untracked.cstore;
785 let cnum = cstore.stable_crate_id_to_crate_num(stable_crate_id);
786 cstore.def_path_hash_to_def_id(cnum, hash)
790 pub fn def_path_debug_str(self, def_id: DefId) -> String {
791 // We are explicitly not going through queries here in order to get
792 // crate name and stable crate id since this code is called from debug!()
793 // statements within the query system and we'd run into endless
794 // recursion otherwise.
795 let (crate_name, stable_crate_id) = if def_id.is_local() {
796 (self.crate_name(LOCAL_CRATE), self.sess.local_stable_crate_id())
798 let cstore = &*self.untracked.cstore;
799 (cstore.crate_name(def_id.krate), cstore.stable_crate_id(def_id.krate))
805 // Don't print the whole stable crate id. That's just
806 // annoying in debug output.
807 stable_crate_id.to_u64() >> 8 * 6,
808 self.def_path(def_id).to_string_no_crate_verbose()
813 impl<'tcx> TyCtxtAt<'tcx> {
814 /// Create a new definition within the incr. comp. engine.
818 data: hir::definitions::DefPathData,
819 ) -> TyCtxtFeed<'tcx, LocalDefId> {
820 // This function modifies `self.definitions` using a side-effect.
821 // We need to ensure that these side effects are re-run by the incr. comp. engine.
822 // Depending on the forever-red node will tell the graph that the calling query
823 // needs to be re-evaluated.
824 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
826 // The following call has the side effect of modifying the tables inside `definitions`.
827 // These very tables are relied on by the incr. comp. engine to decode DepNodes and to
828 // decode the on-disk cache.
830 // Any LocalDefId which is used within queries, either as key or result, either:
831 // - has been created before the construction of the TyCtxt;
832 // - has been created by this call to `create_def`.
833 // As a consequence, this LocalDefId is always re-created before it is needed by the incr.
834 // comp. engine itself.
836 // This call also writes to the value of `source_span` and `expn_that_defined` queries.
837 // This is fine because:
838 // - those queries are `eval_always` so we won't miss their result changing;
839 // - this write will have happened before these queries are called.
840 let key = self.untracked.definitions.write().create_def(parent, data);
842 let feed = TyCtxtFeed { tcx: self.tcx, key };
843 feed.def_span(self.span);
848 impl<'tcx> TyCtxt<'tcx> {
849 pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> + 'tcx {
850 // Create a dependency to the red node to be sure we re-execute this when the amount of
851 // definitions change.
852 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
854 let definitions = &self.untracked.definitions;
855 std::iter::from_generator(|| {
858 // Recompute the number of definitions each time, because our caller may be creating
860 while i < { definitions.read().num_definitions() } {
861 let local_def_index = rustc_span::def_id::DefIndex::from_usize(i);
862 yield LocalDefId { local_def_index };
866 // Leak a read lock once we finish iterating on definitions, to prevent adding new ones.
871 pub fn def_path_table(self) -> &'tcx rustc_hir::definitions::DefPathTable {
872 // Create a dependency to the crate to be sure we re-execute this when the amount of
873 // definitions change.
874 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
876 // Leak a read lock once we start iterating on definitions, to prevent adding new ones
877 // while iterating. If some query needs to add definitions, it should be `ensure`d above.
878 let definitions = self.untracked.definitions.leak();
879 definitions.def_path_table()
882 pub fn def_path_hash_to_def_index_map(
884 ) -> &'tcx rustc_hir::def_path_hash_map::DefPathHashMap {
885 // Create a dependency to the crate to be sure we re-execute this when the amount of
886 // definitions change.
887 self.ensure().hir_crate(());
888 // Leak a read lock once we start iterating on definitions, to prevent adding new ones
889 // while iterating. If some query needs to add definitions, it should be `ensure`d above.
890 let definitions = self.untracked.definitions.leak();
891 definitions.def_path_hash_to_def_index_map()
894 /// Note that this is *untracked* and should only be used within the query
895 /// system if the result is otherwise tracked through queries
896 pub fn cstore_untracked(self) -> &'tcx CrateStoreDyn {
897 &*self.untracked.cstore
900 /// Note that this is *untracked* and should only be used within the query
901 /// system if the result is otherwise tracked through queries
903 pub fn definitions_untracked(self) -> ReadGuard<'tcx, Definitions> {
904 self.untracked.definitions.read()
907 /// Note that this is *untracked* and should only be used within the query
908 /// system if the result is otherwise tracked through queries
910 pub fn source_span_untracked(self, def_id: LocalDefId) -> Span {
911 self.untracked.source_span.get(def_id).copied().unwrap_or(DUMMY_SP)
915 pub fn with_stable_hashing_context<R>(
917 f: impl FnOnce(StableHashingContext<'_>) -> R,
919 f(StableHashingContext::new(self.sess, &self.untracked))
922 pub fn serialize_query_result_cache(self, encoder: FileEncoder) -> FileEncodeResult {
923 self.on_disk_cache.as_ref().map_or(Ok(0), |c| c.serialize(self, encoder))
926 /// If `true`, we should use lazy normalization for constants, otherwise
927 /// we still evaluate them eagerly.
929 pub fn lazy_normalization(self) -> bool {
930 let features = self.features();
931 // Note: We only use lazy normalization for generic const expressions.
932 features.generic_const_exprs
936 pub fn local_crate_exports_generics(self) -> bool {
937 debug_assert!(self.sess.opts.share_generics());
939 self.sess.crate_types().iter().any(|crate_type| {
941 CrateType::Executable
942 | CrateType::Staticlib
943 | CrateType::ProcMacro
944 | CrateType::Cdylib => false,
946 // FIXME rust-lang/rust#64319, rust-lang/rust#64872:
947 // We want to block export of generics from dylibs,
948 // but we must fix rust-lang/rust#65890 before we can
950 CrateType::Dylib => true,
952 CrateType::Rlib => true,
957 /// Returns the `DefId` and the `BoundRegionKind` corresponding to the given region.
958 pub fn is_suitable_region(self, region: Region<'tcx>) -> Option<FreeRegionInfo> {
959 let (suitable_region_binding_scope, bound_region) = match *region {
960 ty::ReFree(ref free_region) => {
961 (free_region.scope.expect_local(), free_region.bound_region)
963 ty::ReEarlyBound(ref ebr) => (
964 self.local_parent(ebr.def_id.expect_local()),
965 ty::BoundRegionKind::BrNamed(ebr.def_id, ebr.name),
967 _ => return None, // not a free region
970 let is_impl_item = match self.hir().find_by_def_id(suitable_region_binding_scope) {
971 Some(Node::Item(..) | Node::TraitItem(..)) => false,
972 Some(Node::ImplItem(..)) => {
973 self.is_bound_region_in_impl_item(suitable_region_binding_scope)
978 Some(FreeRegionInfo {
979 def_id: suitable_region_binding_scope,
980 boundregion: bound_region,
985 /// Given a `DefId` for an `fn`, return all the `dyn` and `impl` traits in its return type.
986 pub fn return_type_impl_or_dyn_traits(
988 scope_def_id: LocalDefId,
989 ) -> Vec<&'tcx hir::Ty<'tcx>> {
990 let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
991 let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id) else {
995 let mut v = TraitObjectVisitor(vec![], self.hir());
996 v.visit_ty(hir_output);
1000 /// Given a `DefId` for an `fn`, return all the `dyn` and `impl` traits in its return type and associated alias span when type alias is used
1001 pub fn return_type_impl_or_dyn_traits_with_type_alias(
1003 scope_def_id: LocalDefId,
1004 ) -> Option<(Vec<&'tcx hir::Ty<'tcx>>, Span)> {
1005 let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
1006 let mut v = TraitObjectVisitor(vec![], self.hir());
1007 // when the return type is a type alias
1008 if let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id)
1009 && let hir::TyKind::Path(hir::QPath::Resolved(
1011 hir::Path { res: hir::def::Res::Def(DefKind::TyAlias, def_id), .. }, )) = hir_output.kind
1012 && let Some(local_id) = def_id.as_local()
1013 && let Some(alias_ty) = self.hir().get_by_def_id(local_id).alias_ty() // it is type alias
1014 && let Some(alias_generics) = self.hir().get_by_def_id(local_id).generics()
1016 v.visit_ty(alias_ty);
1017 if !v.0.is_empty() {
1018 return Some((v.0, alias_generics.span));
1024 pub fn return_type_impl_trait(self, scope_def_id: LocalDefId) -> Option<(Ty<'tcx>, Span)> {
1025 // `type_of()` will fail on these (#55796, #86483), so only allow `fn`s or closures.
1026 match self.hir().get_by_def_id(scope_def_id) {
1027 Node::Item(&hir::Item { kind: ItemKind::Fn(..), .. }) => {}
1028 Node::TraitItem(&hir::TraitItem { kind: TraitItemKind::Fn(..), .. }) => {}
1029 Node::ImplItem(&hir::ImplItem { kind: ImplItemKind::Fn(..), .. }) => {}
1030 Node::Expr(&hir::Expr { kind: ExprKind::Closure { .. }, .. }) => {}
1034 let ret_ty = self.type_of(scope_def_id);
1035 match ret_ty.kind() {
1036 ty::FnDef(_, _) => {
1037 let sig = ret_ty.fn_sig(self);
1038 let output = self.erase_late_bound_regions(sig.output());
1039 if output.is_impl_trait() {
1040 let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
1041 let fn_decl = self.hir().fn_decl_by_hir_id(hir_id).unwrap();
1042 Some((output, fn_decl.output.span()))
1051 /// Checks if the bound region is in Impl Item.
1052 pub fn is_bound_region_in_impl_item(self, suitable_region_binding_scope: LocalDefId) -> bool {
1053 let container_id = self.parent(suitable_region_binding_scope.to_def_id());
1054 if self.impl_trait_ref(container_id).is_some() {
1055 // For now, we do not try to target impls of traits. This is
1056 // because this message is going to suggest that the user
1057 // change the fn signature, but they may not be free to do so,
1058 // since the signature must match the trait.
1060 // FIXME(#42706) -- in some cases, we could do better here.
1066 /// Determines whether identifiers in the assembly have strict naming rules.
1067 /// Currently, only NVPTX* targets need it.
1068 pub fn has_strict_asm_symbol_naming(self) -> bool {
1069 self.sess.target.arch.contains("nvptx")
1072 /// Returns `&'static core::panic::Location<'static>`.
1073 pub fn caller_location_ty(self) -> Ty<'tcx> {
1075 self.lifetimes.re_static,
1076 self.bound_type_of(self.require_lang_item(LangItem::PanicLocation, None))
1077 .subst(self, self.mk_substs([self.lifetimes.re_static.into()].iter())),
1081 /// Returns a displayable description and article for the given `def_id` (e.g. `("a", "struct")`).
1082 pub fn article_and_description(self, def_id: DefId) -> (&'static str, &'static str) {
1083 match self.def_kind(def_id) {
1084 DefKind::Generator => match self.generator_kind(def_id).unwrap() {
1085 rustc_hir::GeneratorKind::Async(..) => ("an", "async closure"),
1086 rustc_hir::GeneratorKind::Gen => ("a", "generator"),
1088 def_kind => (def_kind.article(), def_kind.descr(def_id)),
1092 pub fn type_length_limit(self) -> Limit {
1093 self.limits(()).type_length_limit
1096 pub fn recursion_limit(self) -> Limit {
1097 self.limits(()).recursion_limit
1100 pub fn move_size_limit(self) -> Limit {
1101 self.limits(()).move_size_limit
1104 pub fn const_eval_limit(self) -> Limit {
1105 self.limits(()).const_eval_limit
1108 pub fn all_traits(self) -> impl Iterator<Item = DefId> + 'tcx {
1109 iter::once(LOCAL_CRATE)
1110 .chain(self.crates(()).iter().copied())
1111 .flat_map(move |cnum| self.traits_in_crate(cnum).iter().copied())
1115 pub fn local_visibility(self, def_id: LocalDefId) -> Visibility {
1116 self.visibility(def_id).expect_local()
1120 /// A trait implemented for all `X<'a>` types that can be safely and
1121 /// efficiently converted to `X<'tcx>` as long as they are part of the
1122 /// provided `TyCtxt<'tcx>`.
1123 /// This can be done, for example, for `Ty<'tcx>` or `SubstsRef<'tcx>`
1124 /// by looking them up in their respective interners.
1126 /// However, this is still not the best implementation as it does
1127 /// need to compare the components, even for interned values.
1128 /// It would be more efficient if `TypedArena` provided a way to
1129 /// determine whether the address is in the allocated range.
1131 /// `None` is returned if the value or one of the components is not part
1132 /// of the provided context.
1133 /// For `Ty`, `None` can be returned if either the type interner doesn't
1134 /// contain the `TyKind` key or if the address of the interned
1135 /// pointer differs. The latter case is possible if a primitive type,
1136 /// e.g., `()` or `u8`, was interned in a different context.
1137 pub trait Lift<'tcx>: fmt::Debug {
1138 type Lifted: fmt::Debug + 'tcx;
1139 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted>;
1142 macro_rules! nop_lift {
1143 ($set:ident; $ty:ty => $lifted:ty) => {
1144 impl<'a, 'tcx> Lift<'tcx> for $ty {
1145 type Lifted = $lifted;
1146 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1147 if tcx.interners.$set.contains_pointer_to(&InternedInSet(&*self.0.0)) {
1148 // SAFETY: `self` is interned and therefore valid
1149 // for the entire lifetime of the `TyCtxt`.
1150 Some(unsafe { mem::transmute(self) })
1159 // Can't use the macros as we have reuse the `substs` here.
1161 // See `intern_type_list` for more info.
1162 impl<'a, 'tcx> Lift<'tcx> for &'a List<Ty<'a>> {
1163 type Lifted = &'tcx List<Ty<'tcx>>;
1164 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1165 if self.is_empty() {
1166 return Some(List::empty());
1168 if tcx.interners.substs.contains_pointer_to(&InternedInSet(self.as_substs())) {
1169 // SAFETY: `self` is interned and therefore valid
1170 // for the entire lifetime of the `TyCtxt`.
1171 Some(unsafe { mem::transmute::<&'a List<Ty<'a>>, &'tcx List<Ty<'tcx>>>(self) })
1178 macro_rules! nop_list_lift {
1179 ($set:ident; $ty:ty => $lifted:ty) => {
1180 impl<'a, 'tcx> Lift<'tcx> for &'a List<$ty> {
1181 type Lifted = &'tcx List<$lifted>;
1182 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1183 if self.is_empty() {
1184 return Some(List::empty());
1186 if tcx.interners.$set.contains_pointer_to(&InternedInSet(self)) {
1187 Some(unsafe { mem::transmute(self) })
1196 nop_lift! {type_; Ty<'a> => Ty<'tcx>}
1197 nop_lift! {region; Region<'a> => Region<'tcx>}
1198 nop_lift! {const_; Const<'a> => Const<'tcx>}
1199 nop_lift! {const_allocation; ConstAllocation<'a> => ConstAllocation<'tcx>}
1200 nop_lift! {predicate; Predicate<'a> => Predicate<'tcx>}
1202 nop_list_lift! {poly_existential_predicates; PolyExistentialPredicate<'a> => PolyExistentialPredicate<'tcx>}
1203 nop_list_lift! {predicates; Predicate<'a> => Predicate<'tcx>}
1204 nop_list_lift! {canonical_var_infos; CanonicalVarInfo<'a> => CanonicalVarInfo<'tcx>}
1205 nop_list_lift! {projs; ProjectionKind => ProjectionKind}
1206 nop_list_lift! {bound_variable_kinds; ty::BoundVariableKind => ty::BoundVariableKind}
1208 // This is the impl for `&'a InternalSubsts<'a>`.
1209 nop_list_lift! {substs; GenericArg<'a> => GenericArg<'tcx>}
1211 CloneLiftImpls! { for<'tcx> {
1212 Constness, traits::WellFormedLoc, ImplPolarity, crate::mir::ReturnConstraint,
1216 use super::{ptr_eq, GlobalCtxt, TyCtxt};
1218 use crate::dep_graph::TaskDepsRef;
1219 use crate::ty::query;
1220 use rustc_data_structures::sync::{self, Lock};
1221 use rustc_errors::Diagnostic;
1223 use thin_vec::ThinVec;
1225 #[cfg(not(parallel_compiler))]
1226 use std::cell::Cell;
1228 #[cfg(parallel_compiler)]
1229 use rustc_rayon_core as rayon_core;
1231 /// This is the implicit state of rustc. It contains the current
1232 /// `TyCtxt` and query. It is updated when creating a local interner or
1233 /// executing a new query. Whenever there's a `TyCtxt` value available
1234 /// you should also have access to an `ImplicitCtxt` through the functions
1237 pub struct ImplicitCtxt<'a, 'tcx> {
1238 /// The current `TyCtxt`.
1239 pub tcx: TyCtxt<'tcx>,
1241 /// The current query job, if any. This is updated by `JobOwner::start` in
1242 /// `ty::query::plumbing` when executing a query.
1243 pub query: Option<query::QueryJobId>,
1245 /// Where to store diagnostics for the current query job, if any.
1246 /// This is updated by `JobOwner::start` in `ty::query::plumbing` when executing a query.
1247 pub diagnostics: Option<&'a Lock<ThinVec<Diagnostic>>>,
1249 /// Used to prevent queries from calling too deeply.
1250 pub query_depth: usize,
1252 /// The current dep graph task. This is used to add dependencies to queries
1253 /// when executing them.
1254 pub task_deps: TaskDepsRef<'a>,
1257 impl<'a, 'tcx> ImplicitCtxt<'a, 'tcx> {
1258 pub fn new(gcx: &'tcx GlobalCtxt<'tcx>) -> Self {
1259 let tcx = TyCtxt { gcx };
1265 task_deps: TaskDepsRef::Ignore,
1270 /// Sets Rayon's thread-local variable, which is preserved for Rayon jobs
1271 /// to `value` during the call to `f`. It is restored to its previous value after.
1272 /// This is used to set the pointer to the new `ImplicitCtxt`.
1273 #[cfg(parallel_compiler)]
1275 fn set_tlv<F: FnOnce() -> R, R>(value: usize, f: F) -> R {
1276 rayon_core::tlv::with(value, f)
1279 /// Gets Rayon's thread-local variable, which is preserved for Rayon jobs.
1280 /// This is used to get the pointer to the current `ImplicitCtxt`.
1281 #[cfg(parallel_compiler)]
1283 pub fn get_tlv() -> usize {
1284 rayon_core::tlv::get()
1287 #[cfg(not(parallel_compiler))]
1289 /// A thread local variable that stores a pointer to the current `ImplicitCtxt`.
1290 static TLV: Cell<usize> = const { Cell::new(0) };
1293 /// Sets TLV to `value` during the call to `f`.
1294 /// It is restored to its previous value after.
1295 /// This is used to set the pointer to the new `ImplicitCtxt`.
1296 #[cfg(not(parallel_compiler))]
1298 fn set_tlv<F: FnOnce() -> R, R>(value: usize, f: F) -> R {
1299 let old = get_tlv();
1300 let _reset = rustc_data_structures::OnDrop(move || TLV.with(|tlv| tlv.set(old)));
1301 TLV.with(|tlv| tlv.set(value));
1305 /// Gets the pointer to the current `ImplicitCtxt`.
1306 #[cfg(not(parallel_compiler))]
1308 fn get_tlv() -> usize {
1309 TLV.with(|tlv| tlv.get())
1312 /// Sets `context` as the new current `ImplicitCtxt` for the duration of the function `f`.
1314 pub fn enter_context<'a, 'tcx, F, R>(context: &ImplicitCtxt<'a, 'tcx>, f: F) -> R
1316 F: FnOnce(&ImplicitCtxt<'a, 'tcx>) -> R,
1318 set_tlv(context as *const _ as usize, || f(&context))
1321 /// Allows access to the current `ImplicitCtxt` in a closure if one is available.
1323 pub fn with_context_opt<F, R>(f: F) -> R
1325 F: for<'a, 'tcx> FnOnce(Option<&ImplicitCtxt<'a, 'tcx>>) -> R,
1327 let context = get_tlv();
1331 // We could get an `ImplicitCtxt` pointer from another thread.
1332 // Ensure that `ImplicitCtxt` is `Sync`.
1333 sync::assert_sync::<ImplicitCtxt<'_, '_>>();
1335 unsafe { f(Some(&*(context as *const ImplicitCtxt<'_, '_>))) }
1339 /// Allows access to the current `ImplicitCtxt`.
1340 /// Panics if there is no `ImplicitCtxt` available.
1342 pub fn with_context<F, R>(f: F) -> R
1344 F: for<'a, 'tcx> FnOnce(&ImplicitCtxt<'a, 'tcx>) -> R,
1346 with_context_opt(|opt_context| f(opt_context.expect("no ImplicitCtxt stored in tls")))
1349 /// Allows access to the current `ImplicitCtxt` whose tcx field is the same as the tcx argument
1350 /// passed in. This means the closure is given an `ImplicitCtxt` with the same `'tcx` lifetime
1351 /// as the `TyCtxt` passed in.
1352 /// This will panic if you pass it a `TyCtxt` which is different from the current
1353 /// `ImplicitCtxt`'s `tcx` field.
1355 pub fn with_related_context<'tcx, F, R>(tcx: TyCtxt<'tcx>, f: F) -> R
1357 F: FnOnce(&ImplicitCtxt<'_, 'tcx>) -> R,
1359 with_context(|context| unsafe {
1360 assert!(ptr_eq(context.tcx.gcx, tcx.gcx));
1361 let context: &ImplicitCtxt<'_, '_> = mem::transmute(context);
1366 /// Allows access to the `TyCtxt` in the current `ImplicitCtxt`.
1367 /// Panics if there is no `ImplicitCtxt` available.
1369 pub fn with<F, R>(f: F) -> R
1371 F: for<'tcx> FnOnce(TyCtxt<'tcx>) -> R,
1373 with_context(|context| f(context.tcx))
1376 /// Allows access to the `TyCtxt` in the current `ImplicitCtxt`.
1377 /// The closure is passed None if there is no `ImplicitCtxt` available.
1379 pub fn with_opt<F, R>(f: F) -> R
1381 F: for<'tcx> FnOnce(Option<TyCtxt<'tcx>>) -> R,
1383 with_context_opt(|opt_context| f(opt_context.map(|context| context.tcx)))
1387 macro_rules! sty_debug_print {
1388 ($fmt: expr, $ctxt: expr, $($variant: ident),*) => {{
1389 // Curious inner module to allow variant names to be used as
1391 #[allow(non_snake_case)]
1393 use crate::ty::{self, TyCtxt};
1394 use crate::ty::context::InternedInSet;
1396 #[derive(Copy, Clone)]
1405 pub fn go(fmt: &mut std::fmt::Formatter<'_>, tcx: TyCtxt<'_>) -> std::fmt::Result {
1406 let mut total = DebugStat {
1413 $(let mut $variant = total;)*
1415 let shards = tcx.interners.type_.lock_shards();
1416 let types = shards.iter().flat_map(|shard| shard.keys());
1417 for &InternedInSet(t) in types {
1418 let variant = match t.internee {
1419 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
1420 ty::Float(..) | ty::Str | ty::Never => continue,
1421 ty::Error(_) => /* unimportant */ continue,
1422 $(ty::$variant(..) => &mut $variant,)*
1424 let lt = t.flags.intersects(ty::TypeFlags::HAS_RE_INFER);
1425 let ty = t.flags.intersects(ty::TypeFlags::HAS_TY_INFER);
1426 let ct = t.flags.intersects(ty::TypeFlags::HAS_CT_INFER);
1430 if lt { total.lt_infer += 1; variant.lt_infer += 1 }
1431 if ty { total.ty_infer += 1; variant.ty_infer += 1 }
1432 if ct { total.ct_infer += 1; variant.ct_infer += 1 }
1433 if lt && ty && ct { total.all_infer += 1; variant.all_infer += 1 }
1435 writeln!(fmt, "Ty interner total ty lt ct all")?;
1436 $(writeln!(fmt, " {:18}: {uses:6} {usespc:4.1}%, \
1437 {ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
1438 stringify!($variant),
1439 uses = $variant.total,
1440 usespc = $variant.total as f64 * 100.0 / total.total as f64,
1441 ty = $variant.ty_infer as f64 * 100.0 / total.total as f64,
1442 lt = $variant.lt_infer as f64 * 100.0 / total.total as f64,
1443 ct = $variant.ct_infer as f64 * 100.0 / total.total as f64,
1444 all = $variant.all_infer as f64 * 100.0 / total.total as f64)?;
1446 writeln!(fmt, " total {uses:6} \
1447 {ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
1449 ty = total.ty_infer as f64 * 100.0 / total.total as f64,
1450 lt = total.lt_infer as f64 * 100.0 / total.total as f64,
1451 ct = total.ct_infer as f64 * 100.0 / total.total as f64,
1452 all = total.all_infer as f64 * 100.0 / total.total as f64)
1456 inner::go($fmt, $ctxt)
1460 impl<'tcx> TyCtxt<'tcx> {
1461 pub fn debug_stats(self) -> impl std::fmt::Debug + 'tcx {
1462 struct DebugStats<'tcx>(TyCtxt<'tcx>);
1464 impl<'tcx> std::fmt::Debug for DebugStats<'tcx> {
1465 fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1489 writeln!(fmt, "InternalSubsts interner: #{}", self.0.interners.substs.len())?;
1490 writeln!(fmt, "Region interner: #{}", self.0.interners.region.len())?;
1493 "Const Allocation interner: #{}",
1494 self.0.interners.const_allocation.len()
1496 writeln!(fmt, "Layout interner: #{}", self.0.interners.layout.len())?;
1506 // This type holds a `T` in the interner. The `T` is stored in the arena and
1507 // this type just holds a pointer to it, but it still effectively owns it. It
1508 // impls `Borrow` so that it can be looked up using the original
1509 // (non-arena-memory-owning) types.
1510 struct InternedInSet<'tcx, T: ?Sized>(&'tcx T);
1512 impl<'tcx, T: 'tcx + ?Sized> Clone for InternedInSet<'tcx, T> {
1513 fn clone(&self) -> Self {
1514 InternedInSet(self.0)
1518 impl<'tcx, T: 'tcx + ?Sized> Copy for InternedInSet<'tcx, T> {}
1520 impl<'tcx, T: 'tcx + ?Sized> IntoPointer for InternedInSet<'tcx, T> {
1521 fn into_pointer(&self) -> *const () {
1522 self.0 as *const _ as *const ()
1526 #[allow(rustc::usage_of_ty_tykind)]
1527 impl<'tcx, T> Borrow<T> for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1528 fn borrow(&self) -> &T {
1533 impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1534 fn eq(&self, other: &InternedInSet<'tcx, WithCachedTypeInfo<T>>) -> bool {
1535 // The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
1537 self.0.internee == other.0.internee
1541 impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {}
1543 impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1544 fn hash<H: Hasher>(&self, s: &mut H) {
1545 // The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
1546 self.0.internee.hash(s)
1550 impl<'tcx, T> Borrow<[T]> for InternedInSet<'tcx, List<T>> {
1551 fn borrow(&self) -> &[T] {
1556 impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, List<T>> {
1557 fn eq(&self, other: &InternedInSet<'tcx, List<T>>) -> bool {
1558 // The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
1560 self.0[..] == other.0[..]
1564 impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, List<T>> {}
1566 impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, List<T>> {
1567 fn hash<H: Hasher>(&self, s: &mut H) {
1568 // The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
1573 macro_rules! direct_interners {
1574 ($($name:ident: $method:ident($ty:ty): $ret_ctor:ident -> $ret_ty:ty,)+) => {
1575 $(impl<'tcx> Borrow<$ty> for InternedInSet<'tcx, $ty> {
1576 fn borrow<'a>(&'a self) -> &'a $ty {
1581 impl<'tcx> PartialEq for InternedInSet<'tcx, $ty> {
1582 fn eq(&self, other: &Self) -> bool {
1583 // The `Borrow` trait requires that `x.borrow() == y.borrow()`
1589 impl<'tcx> Eq for InternedInSet<'tcx, $ty> {}
1591 impl<'tcx> Hash for InternedInSet<'tcx, $ty> {
1592 fn hash<H: Hasher>(&self, s: &mut H) {
1593 // The `Borrow` trait requires that `x.borrow().hash(s) ==
1599 impl<'tcx> TyCtxt<'tcx> {
1600 pub fn $method(self, v: $ty) -> $ret_ty {
1601 $ret_ctor(Interned::new_unchecked(self.interners.$name.intern(v, |v| {
1602 InternedInSet(self.interners.arena.alloc(v))
1610 region: mk_region(RegionKind<'tcx>): Region -> Region<'tcx>,
1611 const_: mk_const_internal(ConstData<'tcx>): Const -> Const<'tcx>,
1612 const_allocation: intern_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
1613 layout: intern_layout(LayoutS<VariantIdx>): Layout -> Layout<'tcx>,
1614 adt_def: intern_adt_def(AdtDefData): AdtDef -> AdtDef<'tcx>,
1617 macro_rules! slice_interners {
1618 ($($field:ident: $method:ident($ty:ty)),+ $(,)?) => (
1619 impl<'tcx> TyCtxt<'tcx> {
1620 $(pub fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
1621 self.interners.$field.intern_ref(v, || {
1622 InternedInSet(List::from_arena(&*self.arena, v))
1630 const_lists: _intern_const_list(Const<'tcx>),
1631 substs: _intern_substs(GenericArg<'tcx>),
1632 canonical_var_infos: _intern_canonical_var_infos(CanonicalVarInfo<'tcx>),
1633 poly_existential_predicates:
1634 _intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
1635 predicates: _intern_predicates(Predicate<'tcx>),
1636 projs: _intern_projs(ProjectionKind),
1637 place_elems: _intern_place_elems(PlaceElem<'tcx>),
1638 bound_variable_kinds: _intern_bound_variable_kinds(ty::BoundVariableKind),
1641 impl<'tcx> TyCtxt<'tcx> {
1642 /// Given a `fn` type, returns an equivalent `unsafe fn` type;
1643 /// that is, a `fn` type that is equivalent in every way for being
1645 pub fn safe_to_unsafe_fn_ty(self, sig: PolyFnSig<'tcx>) -> Ty<'tcx> {
1646 assert_eq!(sig.unsafety(), hir::Unsafety::Normal);
1647 self.mk_fn_ptr(sig.map_bound(|sig| ty::FnSig { unsafety: hir::Unsafety::Unsafe, ..sig }))
1650 /// Given the def_id of a Trait `trait_def_id` and the name of an associated item `assoc_name`
1651 /// returns true if the `trait_def_id` defines an associated item of name `assoc_name`.
1652 pub fn trait_may_define_assoc_type(self, trait_def_id: DefId, assoc_name: Ident) -> bool {
1653 self.super_traits_of(trait_def_id).any(|trait_did| {
1654 self.associated_items(trait_did)
1655 .find_by_name_and_kind(self, assoc_name, ty::AssocKind::Type, trait_did)
1660 /// Given a `ty`, return whether it's an `impl Future<...>`.
1661 pub fn ty_is_opaque_future(self, ty: Ty<'_>) -> bool {
1662 let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = ty.kind() else { return false };
1663 let future_trait = self.require_lang_item(LangItem::Future, None);
1665 self.explicit_item_bounds(def_id).iter().any(|(predicate, _)| {
1666 let ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) = predicate.kind().skip_binder() else {
1669 trait_predicate.trait_ref.def_id == future_trait
1670 && trait_predicate.polarity == ImplPolarity::Positive
1674 /// Computes the def-ids of the transitive supertraits of `trait_def_id`. This (intentionally)
1675 /// does not compute the full elaborated super-predicates but just the set of def-ids. It is used
1676 /// to identify which traits may define a given associated type to help avoid cycle errors.
1677 /// Returns a `DefId` iterator.
1678 fn super_traits_of(self, trait_def_id: DefId) -> impl Iterator<Item = DefId> + 'tcx {
1679 let mut set = FxHashSet::default();
1680 let mut stack = vec![trait_def_id];
1682 set.insert(trait_def_id);
1684 iter::from_fn(move || -> Option<DefId> {
1685 let trait_did = stack.pop()?;
1686 let generic_predicates = self.super_predicates_of(trait_did);
1688 for (predicate, _) in generic_predicates.predicates {
1689 if let ty::PredicateKind::Clause(ty::Clause::Trait(data)) =
1690 predicate.kind().skip_binder()
1692 if set.insert(data.def_id()) {
1693 stack.push(data.def_id());
1702 /// Given a closure signature, returns an equivalent fn signature. Detuples
1703 /// and so forth -- so e.g., if we have a sig with `Fn<(u32, i32)>` then
1704 /// you would get a `fn(u32, i32)`.
1705 /// `unsafety` determines the unsafety of the fn signature. If you pass
1706 /// `hir::Unsafety::Unsafe` in the previous example, then you would get
1707 /// an `unsafe fn (u32, i32)`.
1708 /// It cannot convert a closure that requires unsafe.
1709 pub fn signature_unclosure(
1711 sig: PolyFnSig<'tcx>,
1712 unsafety: hir::Unsafety,
1713 ) -> PolyFnSig<'tcx> {
1715 let params_iter = match s.inputs()[0].kind() {
1716 ty::Tuple(params) => params.into_iter(),
1719 self.mk_fn_sig(params_iter, s.output(), s.c_variadic, unsafety, abi::Abi::Rust)
1723 /// Same a `self.mk_region(kind)`, but avoids accessing the interners if
1726 pub fn reuse_or_mk_region(self, r: Region<'tcx>, kind: RegionKind<'tcx>) -> Region<'tcx> {
1727 if *r == kind { r } else { self.mk_region(kind) }
1730 #[allow(rustc::usage_of_ty_tykind)]
1732 pub fn mk_ty(self, st: TyKind<'tcx>) -> Ty<'tcx> {
1733 self.interners.intern_ty(
1736 // This is only used to create a stable hashing context.
1742 pub fn mk_predicate(self, binder: Binder<'tcx, PredicateKind<'tcx>>) -> Predicate<'tcx> {
1743 self.interners.intern_predicate(
1746 // This is only used to create a stable hashing context.
1752 pub fn reuse_or_mk_predicate(
1754 pred: Predicate<'tcx>,
1755 binder: Binder<'tcx, PredicateKind<'tcx>>,
1756 ) -> Predicate<'tcx> {
1757 if pred.kind() != binder { self.mk_predicate(binder) } else { pred }
1760 pub fn mk_mach_int(self, tm: IntTy) -> Ty<'tcx> {
1762 IntTy::Isize => self.types.isize,
1763 IntTy::I8 => self.types.i8,
1764 IntTy::I16 => self.types.i16,
1765 IntTy::I32 => self.types.i32,
1766 IntTy::I64 => self.types.i64,
1767 IntTy::I128 => self.types.i128,
1771 pub fn mk_mach_uint(self, tm: UintTy) -> Ty<'tcx> {
1773 UintTy::Usize => self.types.usize,
1774 UintTy::U8 => self.types.u8,
1775 UintTy::U16 => self.types.u16,
1776 UintTy::U32 => self.types.u32,
1777 UintTy::U64 => self.types.u64,
1778 UintTy::U128 => self.types.u128,
1782 pub fn mk_mach_float(self, tm: FloatTy) -> Ty<'tcx> {
1784 FloatTy::F32 => self.types.f32,
1785 FloatTy::F64 => self.types.f64,
1790 pub fn mk_static_str(self) -> Ty<'tcx> {
1791 self.mk_imm_ref(self.lifetimes.re_static, self.types.str_)
1795 pub fn mk_adt(self, def: AdtDef<'tcx>, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
1796 // Take a copy of substs so that we own the vectors inside.
1797 self.mk_ty(Adt(def, substs))
1801 pub fn mk_foreign(self, def_id: DefId) -> Ty<'tcx> {
1802 self.mk_ty(Foreign(def_id))
1805 fn mk_generic_adt(self, wrapper_def_id: DefId, ty_param: Ty<'tcx>) -> Ty<'tcx> {
1806 let adt_def = self.adt_def(wrapper_def_id);
1808 InternalSubsts::for_item(self, wrapper_def_id, |param, substs| match param.kind {
1809 GenericParamDefKind::Lifetime | GenericParamDefKind::Const { .. } => bug!(),
1810 GenericParamDefKind::Type { has_default, .. } => {
1811 if param.index == 0 {
1814 assert!(has_default);
1815 self.bound_type_of(param.def_id).subst(self, substs).into()
1819 self.mk_ty(Adt(adt_def, substs))
1823 pub fn mk_box(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1824 let def_id = self.require_lang_item(LangItem::OwnedBox, None);
1825 self.mk_generic_adt(def_id, ty)
1829 pub fn mk_lang_item(self, ty: Ty<'tcx>, item: LangItem) -> Option<Ty<'tcx>> {
1830 let def_id = self.lang_items().get(item)?;
1831 Some(self.mk_generic_adt(def_id, ty))
1835 pub fn mk_diagnostic_item(self, ty: Ty<'tcx>, name: Symbol) -> Option<Ty<'tcx>> {
1836 let def_id = self.get_diagnostic_item(name)?;
1837 Some(self.mk_generic_adt(def_id, ty))
1841 pub fn mk_maybe_uninit(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1842 let def_id = self.require_lang_item(LangItem::MaybeUninit, None);
1843 self.mk_generic_adt(def_id, ty)
1847 pub fn mk_ptr(self, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
1848 self.mk_ty(RawPtr(tm))
1852 pub fn mk_ref(self, r: Region<'tcx>, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
1853 self.mk_ty(Ref(r, tm.ty, tm.mutbl))
1857 pub fn mk_mut_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
1858 self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Mut })
1862 pub fn mk_imm_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
1863 self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Not })
1867 pub fn mk_mut_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1868 self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Mut })
1872 pub fn mk_imm_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1873 self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Not })
1877 pub fn mk_array(self, ty: Ty<'tcx>, n: u64) -> Ty<'tcx> {
1878 self.mk_ty(Array(ty, ty::Const::from_usize(self, n)))
1882 pub fn mk_slice(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1883 self.mk_ty(Slice(ty))
1887 pub fn intern_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
1888 self.mk_ty(Tuple(self.intern_type_list(&ts)))
1891 pub fn mk_tup<I: InternAs<Ty<'tcx>, Ty<'tcx>>>(self, iter: I) -> I::Output {
1892 iter.intern_with(|ts| self.mk_ty(Tuple(self.intern_type_list(&ts))))
1896 pub fn mk_unit(self) -> Ty<'tcx> {
1901 pub fn mk_diverging_default(self) -> Ty<'tcx> {
1902 if self.features().never_type_fallback { self.types.never } else { self.types.unit }
1909 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1911 let substs = self.check_substs(def_id, substs);
1912 self.mk_ty(FnDef(def_id, substs))
1919 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1920 ) -> SubstsRef<'tcx> {
1921 let substs = substs.into_iter().map(Into::into);
1922 #[cfg(debug_assertions)]
1924 let n = self.generics_of(_def_id).count();
1928 "wrong number of generic parameters for {_def_id:?}: {:?}",
1929 substs.collect::<Vec<_>>(),
1932 self.mk_substs(substs)
1936 pub fn mk_fn_ptr(self, fty: PolyFnSig<'tcx>) -> Ty<'tcx> {
1937 self.mk_ty(FnPtr(fty))
1943 obj: &'tcx List<PolyExistentialPredicate<'tcx>>,
1944 reg: ty::Region<'tcx>,
1947 self.mk_ty(Dynamic(obj, reg, repr))
1951 pub fn mk_projection(
1954 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1956 self.mk_ty(Alias(ty::Projection, self.mk_alias_ty(item_def_id, substs)))
1960 pub fn mk_closure(self, closure_id: DefId, closure_substs: SubstsRef<'tcx>) -> Ty<'tcx> {
1961 self.mk_ty(Closure(closure_id, closure_substs))
1965 pub fn mk_generator(
1968 generator_substs: SubstsRef<'tcx>,
1969 movability: hir::Movability,
1971 self.mk_ty(Generator(id, generator_substs, movability))
1975 pub fn mk_generator_witness(self, types: ty::Binder<'tcx, &'tcx List<Ty<'tcx>>>) -> Ty<'tcx> {
1976 self.mk_ty(GeneratorWitness(types))
1979 /// Creates a `&mut Context<'_>` [`Ty`] with erased lifetimes.
1980 pub fn mk_task_context(self) -> Ty<'tcx> {
1981 let context_did = self.require_lang_item(LangItem::Context, None);
1982 let context_adt_ref = self.adt_def(context_did);
1983 let context_substs = self.intern_substs(&[self.lifetimes.re_erased.into()]);
1984 let context_ty = self.mk_adt(context_adt_ref, context_substs);
1985 self.mk_mut_ref(self.lifetimes.re_erased, context_ty)
1989 pub fn mk_ty_var(self, v: TyVid) -> Ty<'tcx> {
1990 self.mk_ty_infer(TyVar(v))
1994 pub fn mk_const(self, kind: impl Into<ty::ConstKind<'tcx>>, ty: Ty<'tcx>) -> Const<'tcx> {
1995 self.mk_const_internal(ty::ConstData { kind: kind.into(), ty })
1999 pub fn mk_int_var(self, v: IntVid) -> Ty<'tcx> {
2000 self.mk_ty_infer(IntVar(v))
2004 pub fn mk_float_var(self, v: FloatVid) -> Ty<'tcx> {
2005 self.mk_ty_infer(FloatVar(v))
2009 pub fn mk_ty_infer(self, it: InferTy) -> Ty<'tcx> {
2010 self.mk_ty(Infer(it))
2014 pub fn mk_ty_param(self, index: u32, name: Symbol) -> Ty<'tcx> {
2015 self.mk_ty(Param(ParamTy { index, name }))
2018 pub fn mk_param_from_def(self, param: &ty::GenericParamDef) -> GenericArg<'tcx> {
2020 GenericParamDefKind::Lifetime => {
2021 self.mk_region(ty::ReEarlyBound(param.to_early_bound_region_data())).into()
2023 GenericParamDefKind::Type { .. } => self.mk_ty_param(param.index, param.name).into(),
2024 GenericParamDefKind::Const { .. } => self
2026 ParamConst { index: param.index, name: param.name },
2027 self.type_of(param.def_id),
2034 pub fn mk_opaque(self, def_id: DefId, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
2035 self.mk_ty(Alias(ty::Opaque, self.mk_alias_ty(def_id, substs)))
2038 pub fn mk_place_field(self, place: Place<'tcx>, f: Field, ty: Ty<'tcx>) -> Place<'tcx> {
2039 self.mk_place_elem(place, PlaceElem::Field(f, ty))
2042 pub fn mk_place_deref(self, place: Place<'tcx>) -> Place<'tcx> {
2043 self.mk_place_elem(place, PlaceElem::Deref)
2046 pub fn mk_place_downcast(
2049 adt_def: AdtDef<'tcx>,
2050 variant_index: VariantIdx,
2054 PlaceElem::Downcast(Some(adt_def.variant(variant_index).name), variant_index),
2058 pub fn mk_place_downcast_unnamed(
2061 variant_index: VariantIdx,
2063 self.mk_place_elem(place, PlaceElem::Downcast(None, variant_index))
2066 pub fn mk_place_index(self, place: Place<'tcx>, index: Local) -> Place<'tcx> {
2067 self.mk_place_elem(place, PlaceElem::Index(index))
2070 /// This method copies `Place`'s projection, add an element and reintern it. Should not be used
2071 /// to build a full `Place` it's just a convenient way to grab a projection and modify it in
2073 pub fn mk_place_elem(self, place: Place<'tcx>, elem: PlaceElem<'tcx>) -> Place<'tcx> {
2074 let mut projection = place.projection.to_vec();
2075 projection.push(elem);
2077 Place { local: place.local, projection: self.intern_place_elems(&projection) }
2080 pub fn intern_poly_existential_predicates(
2082 eps: &[PolyExistentialPredicate<'tcx>],
2083 ) -> &'tcx List<PolyExistentialPredicate<'tcx>> {
2084 assert!(!eps.is_empty());
2087 .all(|[a, b]| a.skip_binder().stable_cmp(self, &b.skip_binder())
2088 != Ordering::Greater)
2090 self._intern_poly_existential_predicates(eps)
2093 pub fn intern_predicates(self, preds: &[Predicate<'tcx>]) -> &'tcx List<Predicate<'tcx>> {
2094 // FIXME consider asking the input slice to be sorted to avoid
2095 // re-interning permutations, in which case that would be asserted
2097 if preds.is_empty() {
2098 // The macro-generated method below asserts we don't intern an empty slice.
2101 self._intern_predicates(preds)
2105 pub fn mk_const_list<I: InternAs<ty::Const<'tcx>, &'tcx List<ty::Const<'tcx>>>>(
2109 iter.intern_with(|xs| self.intern_const_list(xs))
2112 pub fn intern_const_list(self, cs: &[ty::Const<'tcx>]) -> &'tcx List<ty::Const<'tcx>> {
2113 if cs.is_empty() { List::empty() } else { self._intern_const_list(cs) }
2116 pub fn intern_type_list(self, ts: &[Ty<'tcx>]) -> &'tcx List<Ty<'tcx>> {
2120 // Actually intern type lists as lists of `GenericArg`s.
2122 // Transmuting from `Ty<'tcx>` to `GenericArg<'tcx>` is sound
2123 // as explained in ty_slice_as_generic_arg`. With this,
2124 // we guarantee that even when transmuting between `List<Ty<'tcx>>`
2125 // and `List<GenericArg<'tcx>>`, the uniqueness requirement for
2127 let substs = self._intern_substs(ty::subst::ty_slice_as_generic_args(ts));
2128 substs.try_as_type_list().unwrap()
2132 pub fn intern_substs(self, ts: &[GenericArg<'tcx>]) -> &'tcx List<GenericArg<'tcx>> {
2133 if ts.is_empty() { List::empty() } else { self._intern_substs(ts) }
2136 pub fn intern_projs(self, ps: &[ProjectionKind]) -> &'tcx List<ProjectionKind> {
2137 if ps.is_empty() { List::empty() } else { self._intern_projs(ps) }
2140 pub fn intern_place_elems(self, ts: &[PlaceElem<'tcx>]) -> &'tcx List<PlaceElem<'tcx>> {
2141 if ts.is_empty() { List::empty() } else { self._intern_place_elems(ts) }
2144 pub fn intern_canonical_var_infos(
2146 ts: &[CanonicalVarInfo<'tcx>],
2147 ) -> CanonicalVarInfos<'tcx> {
2148 if ts.is_empty() { List::empty() } else { self._intern_canonical_var_infos(ts) }
2151 pub fn intern_bound_variable_kinds(
2153 ts: &[ty::BoundVariableKind],
2154 ) -> &'tcx List<ty::BoundVariableKind> {
2155 if ts.is_empty() { List::empty() } else { self._intern_bound_variable_kinds(ts) }
2158 pub fn mk_fn_sig<I>(
2163 unsafety: hir::Unsafety,
2165 ) -> <I::Item as InternIteratorElement<Ty<'tcx>, ty::FnSig<'tcx>>>::Output
2167 I: Iterator<Item: InternIteratorElement<Ty<'tcx>, ty::FnSig<'tcx>>>,
2169 inputs.chain(iter::once(output)).intern_with(|xs| ty::FnSig {
2170 inputs_and_output: self.intern_type_list(xs),
2177 pub fn mk_poly_existential_predicates<
2178 I: InternAs<PolyExistentialPredicate<'tcx>, &'tcx List<PolyExistentialPredicate<'tcx>>>,
2183 iter.intern_with(|xs| self.intern_poly_existential_predicates(xs))
2186 pub fn mk_predicates<I: InternAs<Predicate<'tcx>, &'tcx List<Predicate<'tcx>>>>(
2190 iter.intern_with(|xs| self.intern_predicates(xs))
2193 pub fn mk_type_list<I: InternAs<Ty<'tcx>, &'tcx List<Ty<'tcx>>>>(self, iter: I) -> I::Output {
2194 iter.intern_with(|xs| self.intern_type_list(xs))
2197 pub fn mk_substs<I: InternAs<GenericArg<'tcx>, &'tcx List<GenericArg<'tcx>>>>(
2201 iter.intern_with(|xs| self.intern_substs(xs))
2204 pub fn mk_place_elems<I: InternAs<PlaceElem<'tcx>, &'tcx List<PlaceElem<'tcx>>>>(
2208 iter.intern_with(|xs| self.intern_place_elems(xs))
2211 pub fn mk_substs_trait(
2214 rest: impl IntoIterator<Item = GenericArg<'tcx>>,
2215 ) -> SubstsRef<'tcx> {
2216 self.mk_substs(iter::once(self_ty.into()).chain(rest))
2219 pub fn mk_trait_ref(
2221 trait_def_id: DefId,
2222 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
2223 ) -> ty::TraitRef<'tcx> {
2224 let substs = self.check_substs(trait_def_id, substs);
2225 ty::TraitRef { def_id: trait_def_id, substs, _use_mk_trait_ref_instead: () }
2231 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
2232 ) -> ty::AliasTy<'tcx> {
2233 let substs = self.check_substs(def_id, substs);
2234 ty::AliasTy { def_id, substs, _use_mk_alias_ty_instead: () }
2237 pub fn mk_bound_variable_kinds<
2238 I: InternAs<ty::BoundVariableKind, &'tcx List<ty::BoundVariableKind>>,
2243 iter.intern_with(|xs| self.intern_bound_variable_kinds(xs))
2246 /// Emit a lint at `span` from a lint struct (some type that implements `DecorateLint`,
2247 /// typically generated by `#[derive(LintDiagnostic)]`).
2248 pub fn emit_spanned_lint(
2250 lint: &'static Lint,
2252 span: impl Into<MultiSpan>,
2253 decorator: impl for<'a> DecorateLint<'a, ()>,
2255 let msg = decorator.msg();
2256 let (level, src) = self.lint_level_at_node(lint, hir_id);
2257 struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, |diag| {
2258 decorator.decorate_lint(diag)
2262 /// Emit a lint at the appropriate level for a hir node, with an associated span.
2264 /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
2266 /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
2267 #[rustc_lint_diagnostics]
2268 pub fn struct_span_lint_hir(
2270 lint: &'static Lint,
2272 span: impl Into<MultiSpan>,
2273 msg: impl Into<DiagnosticMessage>,
2274 decorate: impl for<'a, 'b> FnOnce(
2275 &'b mut DiagnosticBuilder<'a, ()>,
2276 ) -> &'b mut DiagnosticBuilder<'a, ()>,
2278 let (level, src) = self.lint_level_at_node(lint, hir_id);
2279 struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, decorate);
2282 /// Emit a lint from a lint struct (some type that implements `DecorateLint`, typically
2283 /// generated by `#[derive(LintDiagnostic)]`).
2286 lint: &'static Lint,
2288 decorator: impl for<'a> DecorateLint<'a, ()>,
2290 self.struct_lint_node(lint, id, decorator.msg(), |diag| decorator.decorate_lint(diag))
2293 /// Emit a lint at the appropriate level for a hir node.
2295 /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
2297 /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
2298 #[rustc_lint_diagnostics]
2299 pub fn struct_lint_node(
2301 lint: &'static Lint,
2303 msg: impl Into<DiagnosticMessage>,
2304 decorate: impl for<'a, 'b> FnOnce(
2305 &'b mut DiagnosticBuilder<'a, ()>,
2306 ) -> &'b mut DiagnosticBuilder<'a, ()>,
2308 let (level, src) = self.lint_level_at_node(lint, id);
2309 struct_lint_level(self.sess, lint, level, src, None, msg, decorate);
2312 pub fn in_scope_traits(self, id: HirId) -> Option<&'tcx [TraitCandidate]> {
2313 let map = self.in_scope_traits_map(id.owner)?;
2314 let candidates = map.get(&id.local_id)?;
2318 pub fn named_region(self, id: HirId) -> Option<resolve_lifetime::Region> {
2319 debug!(?id, "named_region");
2320 self.named_region_map(id.owner).and_then(|map| map.get(&id.local_id).cloned())
2323 pub fn is_late_bound(self, id: HirId) -> bool {
2324 self.is_late_bound_map(id.owner.def_id).map_or(false, |set| {
2325 let def_id = self.hir().local_def_id(id);
2326 set.contains(&def_id)
2330 pub fn late_bound_vars(self, id: HirId) -> &'tcx List<ty::BoundVariableKind> {
2331 self.mk_bound_variable_kinds(
2332 self.late_bound_vars_map(id.owner)
2333 .and_then(|map| map.get(&id.local_id).cloned())
2334 .unwrap_or_else(|| {
2335 bug!("No bound vars found for {:?} ({:?})", self.hir().node_to_string(id), id)
2341 /// Whether the `def_id` counts as const fn in the current crate, considering all active
2343 pub fn is_const_fn(self, def_id: DefId) -> bool {
2344 if self.is_const_fn_raw(def_id) {
2345 match self.lookup_const_stability(def_id) {
2346 Some(stability) if stability.is_const_unstable() => {
2347 // has a `rustc_const_unstable` attribute, check whether the user enabled the
2348 // corresponding feature gate.
2350 .declared_lib_features
2352 .any(|&(sym, _)| sym == stability.feature)
2354 // functions without const stability are either stable user written
2355 // const fn or the user is using feature gates and we thus don't
2356 // care what they do
2364 /// Whether the trait impl is marked const. This does not consider stability or feature gates.
2365 pub fn is_const_trait_impl_raw(self, def_id: DefId) -> bool {
2366 let Some(local_def_id) = def_id.as_local() else { return false };
2367 let hir_id = self.local_def_id_to_hir_id(local_def_id);
2368 let node = self.hir().get(hir_id);
2372 hir::Node::Item(hir::Item {
2373 kind: hir::ItemKind::Impl(hir::Impl { constness: hir::Constness::Const, .. }),
2380 impl<'tcx> TyCtxtAt<'tcx> {
2381 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
2383 pub fn ty_error(self) -> Ty<'tcx> {
2384 self.tcx.ty_error_with_message(self.span, "TyKind::Error constructed but no error reported")
2387 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg to
2388 /// ensure it gets used.
2390 pub fn ty_error_with_message(self, msg: &str) -> Ty<'tcx> {
2391 self.tcx.ty_error_with_message(self.span, msg)
2394 pub fn mk_trait_ref(
2396 trait_lang_item: LangItem,
2397 substs: impl IntoIterator<Item = impl Into<ty::GenericArg<'tcx>>>,
2398 ) -> ty::TraitRef<'tcx> {
2399 let trait_def_id = self.require_lang_item(trait_lang_item, Some(self.span));
2400 self.tcx.mk_trait_ref(trait_def_id, substs)
2404 /// Parameter attributes that can only be determined by examining the body of a function instead
2405 /// of just its signature.
2407 /// These can be useful for optimization purposes when a function is directly called. We compute
2408 /// them and store them into the crate metadata so that downstream crates can make use of them.
2410 /// Right now, we only have `read_only`, but `no_capture` and `no_alias` might be useful in the
2412 #[derive(Clone, Copy, PartialEq, Debug, Default, TyDecodable, TyEncodable, HashStable)]
2413 pub struct DeducedParamAttrs {
2414 /// The parameter is marked immutable in the function and contains no `UnsafeCell` (i.e. its
2415 /// type is freeze).
2416 pub read_only: bool,
2419 // We are comparing types with different invariant lifetimes, so `ptr::eq`
2420 // won't work for us.
2421 fn ptr_eq<T, U>(t: *const T, u: *const U) -> bool {
2422 t as *const () == u as *const ()
2425 pub fn provide(providers: &mut ty::query::Providers) {
2426 providers.module_reexports =
2427 |tcx, id| tcx.resolutions(()).reexport_map.get(&id).map(|v| &v[..]);
2428 providers.maybe_unused_trait_imports =
2429 |tcx, ()| &tcx.resolutions(()).maybe_unused_trait_imports;
2430 providers.maybe_unused_extern_crates =
2431 |tcx, ()| &tcx.resolutions(()).maybe_unused_extern_crates[..];
2432 providers.names_imported_by_glob_use = |tcx, id| {
2433 tcx.arena.alloc(tcx.resolutions(()).glob_map.get(&id).cloned().unwrap_or_default())
2436 providers.extern_mod_stmt_cnum =
2437 |tcx, id| tcx.resolutions(()).extern_crate_map.get(&id).cloned();
2438 providers.is_panic_runtime = |tcx, cnum| {
2439 assert_eq!(cnum, LOCAL_CRATE);
2440 tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::panic_runtime)
2442 providers.is_compiler_builtins = |tcx, cnum| {
2443 assert_eq!(cnum, LOCAL_CRATE);
2444 tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::compiler_builtins)
2446 providers.has_panic_handler = |tcx, cnum| {
2447 assert_eq!(cnum, LOCAL_CRATE);
2448 // We want to check if the panic handler was defined in this crate
2449 tcx.lang_items().panic_impl().map_or(false, |did| did.is_local())
2451 providers.source_span =
2452 |tcx, def_id| tcx.untracked.source_span.get(def_id).copied().unwrap_or(DUMMY_SP);