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 const TINY_CONST_EVAL_LIMIT: Limit = Limit(20);
80 pub trait OnDiskCache<'tcx>: rustc_data_structures::sync::Sync {
81 /// Creates a new `OnDiskCache` instance from the serialized data in `data`.
82 fn new(sess: &'tcx Session, data: Mmap, start_pos: usize) -> Self
86 fn new_empty(source_map: &'tcx SourceMap) -> Self
90 fn drop_serialized_data(&self, tcx: TyCtxt<'tcx>);
92 fn serialize(&self, tcx: TyCtxt<'tcx>, encoder: FileEncoder) -> FileEncodeResult;
95 #[allow(rustc::usage_of_ty_tykind)]
96 impl<'tcx> Interner for TyCtxt<'tcx> {
97 type AdtDef = ty::AdtDef<'tcx>;
98 type SubstsRef = ty::SubstsRef<'tcx>;
101 type Const = ty::Const<'tcx>;
102 type Region = Region<'tcx>;
103 type TypeAndMut = TypeAndMut<'tcx>;
104 type Mutability = hir::Mutability;
105 type Movability = hir::Movability;
106 type PolyFnSig = PolyFnSig<'tcx>;
107 type ListBinderExistentialPredicate = &'tcx List<PolyExistentialPredicate<'tcx>>;
108 type BinderListTy = Binder<'tcx, &'tcx List<Ty<'tcx>>>;
109 type ListTy = &'tcx List<Ty<'tcx>>;
110 type AliasTy = ty::AliasTy<'tcx>;
111 type ParamTy = ParamTy;
112 type BoundTy = ty::BoundTy;
113 type PlaceholderType = ty::PlaceholderType;
114 type InferTy = InferTy;
115 type ErrorGuaranteed = ErrorGuaranteed;
116 type PredicateKind = ty::PredicateKind<'tcx>;
117 type AllocId = crate::mir::interpret::AllocId;
119 type EarlyBoundRegion = ty::EarlyBoundRegion;
120 type BoundRegion = ty::BoundRegion;
121 type FreeRegion = ty::FreeRegion;
122 type RegionVid = ty::RegionVid;
123 type PlaceholderRegion = ty::PlaceholderRegion;
126 type InternedSet<'tcx, T> = ShardedHashMap<InternedInSet<'tcx, T>, ()>;
128 pub struct CtxtInterners<'tcx> {
129 /// The arena that types, regions, etc. are allocated from.
130 arena: &'tcx WorkerLocal<Arena<'tcx>>,
132 // Specifically use a speedy hash algorithm for these hash sets, since
133 // they're accessed quite often.
134 type_: InternedSet<'tcx, WithCachedTypeInfo<TyKind<'tcx>>>,
135 const_lists: InternedSet<'tcx, List<ty::Const<'tcx>>>,
136 substs: InternedSet<'tcx, InternalSubsts<'tcx>>,
137 canonical_var_infos: InternedSet<'tcx, List<CanonicalVarInfo<'tcx>>>,
138 region: InternedSet<'tcx, RegionKind<'tcx>>,
139 poly_existential_predicates: InternedSet<'tcx, List<PolyExistentialPredicate<'tcx>>>,
140 predicate: InternedSet<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>,
141 predicates: InternedSet<'tcx, List<Predicate<'tcx>>>,
142 projs: InternedSet<'tcx, List<ProjectionKind>>,
143 place_elems: InternedSet<'tcx, List<PlaceElem<'tcx>>>,
144 const_: InternedSet<'tcx, ConstData<'tcx>>,
145 const_allocation: InternedSet<'tcx, Allocation>,
146 bound_variable_kinds: InternedSet<'tcx, List<ty::BoundVariableKind>>,
147 layout: InternedSet<'tcx, LayoutS<VariantIdx>>,
148 adt_def: InternedSet<'tcx, AdtDefData>,
151 impl<'tcx> CtxtInterners<'tcx> {
152 fn new(arena: &'tcx WorkerLocal<Arena<'tcx>>) -> CtxtInterners<'tcx> {
155 type_: Default::default(),
156 const_lists: Default::default(),
157 substs: Default::default(),
158 region: Default::default(),
159 poly_existential_predicates: Default::default(),
160 canonical_var_infos: Default::default(),
161 predicate: Default::default(),
162 predicates: Default::default(),
163 projs: Default::default(),
164 place_elems: Default::default(),
165 const_: Default::default(),
166 const_allocation: Default::default(),
167 bound_variable_kinds: Default::default(),
168 layout: Default::default(),
169 adt_def: Default::default(),
174 #[allow(rustc::usage_of_ty_tykind)]
176 fn intern_ty(&self, kind: TyKind<'tcx>, sess: &Session, untracked: &Untracked) -> Ty<'tcx> {
177 Ty(Interned::new_unchecked(
179 .intern(kind, |kind| {
180 let flags = super::flags::FlagComputation::for_kind(&kind);
181 let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
183 InternedInSet(self.arena.alloc(WithCachedTypeInfo {
187 outer_exclusive_binder: flags.outer_exclusive_binder,
194 fn stable_hash<'a, T: HashStable<StableHashingContext<'a>>>(
196 flags: &ty::flags::FlagComputation,
198 untracked: &'a Untracked,
201 // It's impossible to hash inference variables (and will ICE), so we don't need to try to cache them.
202 // Without incremental, we rarely stable-hash types, so let's not do it proactively.
203 if flags.flags.intersects(TypeFlags::NEEDS_INFER) || sess.opts.incremental.is_none() {
206 let mut hasher = StableHasher::new();
207 let mut hcx = StableHashingContext::new(sess, untracked);
208 val.hash_stable(&mut hcx, &mut hasher);
216 kind: Binder<'tcx, PredicateKind<'tcx>>,
218 untracked: &Untracked,
219 ) -> Predicate<'tcx> {
220 Predicate(Interned::new_unchecked(
222 .intern(kind, |kind| {
223 let flags = super::flags::FlagComputation::for_predicate(kind);
225 let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
227 InternedInSet(self.arena.alloc(WithCachedTypeInfo {
231 outer_exclusive_binder: flags.outer_exclusive_binder,
239 pub struct CommonTypes<'tcx> {
259 pub self_param: Ty<'tcx>,
261 /// Dummy type used for the `Self` of a `TraitRef` created for converting
262 /// a trait object, and which gets removed in `ExistentialTraitRef`.
263 /// This type must not appear anywhere in other converted types.
264 pub trait_object_dummy_self: Ty<'tcx>,
267 pub struct CommonLifetimes<'tcx> {
269 pub re_static: Region<'tcx>,
271 /// Erased region, used outside of type inference.
272 pub re_erased: Region<'tcx>,
275 pub struct CommonConsts<'tcx> {
276 pub unit: Const<'tcx>,
279 impl<'tcx> CommonTypes<'tcx> {
281 interners: &CtxtInterners<'tcx>,
283 untracked: &Untracked,
284 ) -> CommonTypes<'tcx> {
285 let mk = |ty| interners.intern_ty(ty, sess, untracked);
288 unit: mk(Tuple(List::empty())),
292 isize: mk(Int(ty::IntTy::Isize)),
293 i8: mk(Int(ty::IntTy::I8)),
294 i16: mk(Int(ty::IntTy::I16)),
295 i32: mk(Int(ty::IntTy::I32)),
296 i64: mk(Int(ty::IntTy::I64)),
297 i128: mk(Int(ty::IntTy::I128)),
298 usize: mk(Uint(ty::UintTy::Usize)),
299 u8: mk(Uint(ty::UintTy::U8)),
300 u16: mk(Uint(ty::UintTy::U16)),
301 u32: mk(Uint(ty::UintTy::U32)),
302 u64: mk(Uint(ty::UintTy::U64)),
303 u128: mk(Uint(ty::UintTy::U128)),
304 f32: mk(Float(ty::FloatTy::F32)),
305 f64: mk(Float(ty::FloatTy::F64)),
307 self_param: mk(ty::Param(ty::ParamTy { index: 0, name: kw::SelfUpper })),
309 trait_object_dummy_self: mk(Infer(ty::FreshTy(0))),
314 impl<'tcx> CommonLifetimes<'tcx> {
315 fn new(interners: &CtxtInterners<'tcx>) -> CommonLifetimes<'tcx> {
317 Region(Interned::new_unchecked(
318 interners.region.intern(r, |r| InternedInSet(interners.arena.alloc(r))).0,
322 CommonLifetimes { re_static: mk(ty::ReStatic), re_erased: mk(ty::ReErased) }
326 impl<'tcx> CommonConsts<'tcx> {
327 fn new(interners: &CtxtInterners<'tcx>, types: &CommonTypes<'tcx>) -> CommonConsts<'tcx> {
329 Const(Interned::new_unchecked(
330 interners.const_.intern(c, |c| InternedInSet(interners.arena.alloc(c))).0,
335 unit: mk_const(ty::ConstData {
336 kind: ty::ConstKind::Value(ty::ValTree::zst()),
343 /// This struct contains information regarding the `ReFree(FreeRegion)` corresponding to a lifetime
346 pub struct FreeRegionInfo {
347 /// `LocalDefId` corresponding to FreeRegion
348 pub def_id: LocalDefId,
349 /// the bound region corresponding to FreeRegion
350 pub boundregion: ty::BoundRegionKind,
351 /// checks if bound region is in Impl Item
352 pub is_impl_item: bool,
355 /// This struct should only be created by `create_def`.
356 #[derive(Copy, Clone)]
357 pub struct TyCtxtFeed<'tcx, KEY: Copy> {
358 pub tcx: TyCtxt<'tcx>,
359 // Do not allow direct access, as downstream code must not mutate this field.
363 impl<'tcx> TyCtxt<'tcx> {
364 pub fn feed_unit_query(self) -> TyCtxtFeed<'tcx, ()> {
365 TyCtxtFeed { tcx: self, key: () }
367 pub fn feed_local_crate(self) -> TyCtxtFeed<'tcx, CrateNum> {
368 TyCtxtFeed { tcx: self, key: LOCAL_CRATE }
372 impl<'tcx, KEY: Copy> TyCtxtFeed<'tcx, KEY> {
374 pub fn key(&self) -> KEY {
379 impl<'tcx> TyCtxtFeed<'tcx, LocalDefId> {
381 pub fn def_id(&self) -> LocalDefId {
386 /// The central data structure of the compiler. It stores references
387 /// to the various **arenas** and also houses the results of the
388 /// various **compiler queries** that have been performed. See the
389 /// [rustc dev guide] for more details.
391 /// [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/ty.html
392 #[derive(Copy, Clone)]
393 #[rustc_diagnostic_item = "TyCtxt"]
394 #[rustc_pass_by_value]
395 pub struct TyCtxt<'tcx> {
396 gcx: &'tcx GlobalCtxt<'tcx>,
399 impl<'tcx> Deref for TyCtxt<'tcx> {
400 type Target = &'tcx GlobalCtxt<'tcx>;
402 fn deref(&self) -> &Self::Target {
407 pub struct GlobalCtxt<'tcx> {
408 pub arena: &'tcx WorkerLocal<Arena<'tcx>>,
409 pub hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
411 interners: CtxtInterners<'tcx>,
413 pub sess: &'tcx Session,
415 /// This only ever stores a `LintStore` but we don't want a dependency on that type here.
417 /// FIXME(Centril): consider `dyn LintStoreMarker` once
418 /// we can upcast to `Any` for some additional type safety.
419 pub lint_store: Lrc<dyn Any + sync::Sync + sync::Send>,
421 pub dep_graph: DepGraph,
423 pub prof: SelfProfilerRef,
425 /// Common types, pre-interned for your convenience.
426 pub types: CommonTypes<'tcx>,
428 /// Common lifetimes, pre-interned for your convenience.
429 pub lifetimes: CommonLifetimes<'tcx>,
431 /// Common consts, pre-interned for your convenience.
432 pub consts: CommonConsts<'tcx>,
434 untracked: Untracked,
436 /// This provides access to the incremental compilation on-disk cache for query results.
437 /// Do not access this directly. It is only meant to be used by
438 /// `DepGraph::try_mark_green()` and the query infrastructure.
439 /// This is `None` if we are not incremental compilation mode
440 pub on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
442 pub queries: &'tcx dyn query::QueryEngine<'tcx>,
443 pub query_caches: query::QueryCaches<'tcx>,
444 pub(crate) query_kinds: &'tcx [DepKindStruct<'tcx>],
446 // Internal caches for metadata decoding. No need to track deps on this.
447 pub ty_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
448 pub pred_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Predicate<'tcx>>>,
450 /// Caches the results of trait selection. This cache is used
451 /// for things that do not have to do with the parameters in scope.
452 pub selection_cache: traits::SelectionCache<'tcx>,
454 /// Caches the results of trait evaluation. This cache is used
455 /// for things that do not have to do with the parameters in scope.
456 /// Merge this with `selection_cache`?
457 pub evaluation_cache: traits::EvaluationCache<'tcx>,
459 /// Data layout specification for the current target.
460 pub data_layout: TargetDataLayout,
462 /// Stores memory for globals (statics/consts).
463 pub(crate) alloc_map: Lock<interpret::AllocMap<'tcx>>,
466 impl<'tcx> TyCtxt<'tcx> {
467 /// Expects a body and returns its codegen attributes.
469 /// Unlike `codegen_fn_attrs`, this returns `CodegenFnAttrs::EMPTY` for
471 pub fn body_codegen_attrs(self, def_id: DefId) -> &'tcx CodegenFnAttrs {
472 let def_kind = self.def_kind(def_id);
473 if def_kind.has_codegen_attrs() {
474 self.codegen_fn_attrs(def_id)
477 DefKind::AnonConst | DefKind::AssocConst | DefKind::Const | DefKind::InlineConst
479 CodegenFnAttrs::EMPTY
482 "body_codegen_fn_attrs called on unexpected definition: {:?} {:?}",
489 pub fn typeck_opt_const_arg(
491 def: ty::WithOptConstParam<LocalDefId>,
492 ) -> &'tcx TypeckResults<'tcx> {
493 if let Some(param_did) = def.const_param_did {
494 self.typeck_const_arg((def.did, param_did))
500 pub fn mir_borrowck_opt_const_arg(
502 def: ty::WithOptConstParam<LocalDefId>,
503 ) -> &'tcx BorrowCheckResult<'tcx> {
504 if let Some(param_did) = def.const_param_did {
505 self.mir_borrowck_const_arg((def.did, param_did))
507 self.mir_borrowck(def.did)
511 pub fn alloc_steal_thir(self, thir: Thir<'tcx>) -> &'tcx Steal<Thir<'tcx>> {
512 self.arena.alloc(Steal::new(thir))
515 pub fn alloc_steal_mir(self, mir: Body<'tcx>) -> &'tcx Steal<Body<'tcx>> {
516 self.arena.alloc(Steal::new(mir))
519 pub fn alloc_steal_promoted(
521 promoted: IndexVec<Promoted, Body<'tcx>>,
522 ) -> &'tcx Steal<IndexVec<Promoted, Body<'tcx>>> {
523 self.arena.alloc(Steal::new(promoted))
526 pub fn alloc_adt_def(
530 variants: IndexVec<VariantIdx, ty::VariantDef>,
532 ) -> ty::AdtDef<'tcx> {
533 self.intern_adt_def(ty::AdtDefData::new(self, did, kind, variants, repr))
536 /// Allocates a read-only byte or string literal for `mir::interpret`.
537 pub fn allocate_bytes(self, bytes: &[u8]) -> interpret::AllocId {
538 // Create an allocation that just contains these bytes.
539 let alloc = interpret::Allocation::from_bytes_byte_aligned_immutable(bytes);
540 let alloc = self.intern_const_alloc(alloc);
541 self.create_memory_alloc(alloc)
544 /// Returns a range of the start/end indices specified with the
545 /// `rustc_layout_scalar_valid_range` attribute.
546 // FIXME(eddyb) this is an awkward spot for this method, maybe move it?
547 pub fn layout_scalar_valid_range(self, def_id: DefId) -> (Bound<u128>, Bound<u128>) {
549 let Some(attr) = self.get_attr(def_id, name) else {
550 return Bound::Unbounded;
552 debug!("layout_scalar_valid_range: attr={:?}", attr);
555 ast::NestedMetaItem::Lit(ast::MetaItemLit {
556 kind: ast::LitKind::Int(a, _),
560 ) = attr.meta_item_list().as_deref()
565 .delay_span_bug(attr.span, "invalid rustc_layout_scalar_valid_range attribute");
570 get(sym::rustc_layout_scalar_valid_range_start),
571 get(sym::rustc_layout_scalar_valid_range_end),
575 pub fn lift<T: Lift<'tcx>>(self, value: T) -> Option<T::Lifted> {
576 value.lift_to_tcx(self)
579 /// Creates a type context and call the closure with a `TyCtxt` reference
580 /// to the context. The closure enforces that the type context and any interned
581 /// value (types, substs, etc.) can only be used while `ty::tls` has a valid
582 /// reference to the context, to allow formatting values that need it.
583 pub fn create_global_ctxt(
585 lint_store: Lrc<dyn Any + sync::Send + sync::Sync>,
586 arena: &'tcx WorkerLocal<Arena<'tcx>>,
587 hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
588 untracked: Untracked,
590 on_disk_cache: Option<&'tcx dyn OnDiskCache<'tcx>>,
591 queries: &'tcx dyn query::QueryEngine<'tcx>,
592 query_kinds: &'tcx [DepKindStruct<'tcx>],
593 ) -> GlobalCtxt<'tcx> {
594 let data_layout = s.target.parse_data_layout().unwrap_or_else(|err| {
597 let interners = CtxtInterners::new(arena);
598 let common_types = CommonTypes::new(&interners, s, &untracked);
599 let common_lifetimes = CommonLifetimes::new(&interners);
600 let common_consts = CommonConsts::new(&interners, &common_types);
609 prof: s.prof.clone(),
611 lifetimes: common_lifetimes,
612 consts: common_consts,
616 query_caches: query::QueryCaches::default(),
618 ty_rcache: Default::default(),
619 pred_rcache: Default::default(),
620 selection_cache: Default::default(),
621 evaluation_cache: Default::default(),
623 alloc_map: Lock::new(interpret::AllocMap::new()),
627 /// Constructs a `TyKind::Error` type with current `ErrorGuaranteed`
629 pub fn ty_error_with_guaranteed(self, reported: ErrorGuaranteed) -> Ty<'tcx> {
630 self.mk_ty(Error(reported))
633 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
635 pub fn ty_error(self) -> Ty<'tcx> {
636 self.ty_error_with_message(DUMMY_SP, "TyKind::Error constructed but no error reported")
639 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg` to
640 /// ensure it gets used.
642 pub fn ty_error_with_message<S: Into<MultiSpan>>(self, span: S, msg: &str) -> Ty<'tcx> {
643 let reported = self.sess.delay_span_bug(span, msg);
644 self.mk_ty(Error(reported))
647 /// Like [TyCtxt::ty_error] but for constants, with current `ErrorGuaranteed`
649 pub fn const_error_with_guaranteed(
652 reported: ErrorGuaranteed,
654 self.mk_const(ty::ConstKind::Error(reported), ty)
657 /// Like [TyCtxt::ty_error] but for constants.
659 pub fn const_error(self, ty: Ty<'tcx>) -> Const<'tcx> {
660 self.const_error_with_message(
663 "ty::ConstKind::Error constructed but no error reported",
667 /// Like [TyCtxt::ty_error_with_message] but for constants.
669 pub fn const_error_with_message<S: Into<MultiSpan>>(
675 let reported = self.sess.delay_span_bug(span, msg);
676 self.mk_const(ty::ConstKind::Error(reported), ty)
679 pub fn consider_optimizing<T: Fn() -> String>(self, msg: T) -> bool {
680 let cname = self.crate_name(LOCAL_CRATE);
681 self.sess.consider_optimizing(cname.as_str(), msg)
684 /// Obtain all lang items of this crate and all dependencies (recursively)
685 pub fn lang_items(self) -> &'tcx rustc_hir::lang_items::LanguageItems {
686 self.get_lang_items(())
689 /// Obtain the given diagnostic item's `DefId`. Use `is_diagnostic_item` if you just want to
690 /// compare against another `DefId`, since `is_diagnostic_item` is cheaper.
691 pub fn get_diagnostic_item(self, name: Symbol) -> Option<DefId> {
692 self.all_diagnostic_items(()).name_to_id.get(&name).copied()
695 /// Obtain the diagnostic item's name
696 pub fn get_diagnostic_name(self, id: DefId) -> Option<Symbol> {
697 self.diagnostic_items(id.krate).id_to_name.get(&id).copied()
700 /// Check whether the diagnostic item with the given `name` has the given `DefId`.
701 pub fn is_diagnostic_item(self, name: Symbol, did: DefId) -> bool {
702 self.diagnostic_items(did.krate).name_to_id.get(&name) == Some(&did)
705 /// Returns `true` if the node pointed to by `def_id` is a generator for an async construct.
706 pub fn generator_is_async(self, def_id: DefId) -> bool {
707 matches!(self.generator_kind(def_id), Some(hir::GeneratorKind::Async(_)))
710 pub fn stability(self) -> &'tcx stability::Index {
711 self.stability_index(())
714 pub fn features(self) -> &'tcx rustc_feature::Features {
715 self.features_query(())
718 pub fn def_key(self, id: DefId) -> rustc_hir::definitions::DefKey {
719 // Accessing the DefKey is ok, since it is part of DefPathHash.
720 if let Some(id) = id.as_local() {
721 self.definitions_untracked().def_key(id)
723 self.untracked.cstore.def_key(id)
727 /// Converts a `DefId` into its fully expanded `DefPath` (every
728 /// `DefId` is really just an interned `DefPath`).
730 /// Note that if `id` is not local to this crate, the result will
731 /// be a non-local `DefPath`.
732 pub fn def_path(self, id: DefId) -> rustc_hir::definitions::DefPath {
733 // Accessing the DefPath is ok, since it is part of DefPathHash.
734 if let Some(id) = id.as_local() {
735 self.definitions_untracked().def_path(id)
737 self.untracked.cstore.def_path(id)
742 pub fn def_path_hash(self, def_id: DefId) -> rustc_hir::definitions::DefPathHash {
743 // Accessing the DefPathHash is ok, it is incr. comp. stable.
744 if let Some(def_id) = def_id.as_local() {
745 self.definitions_untracked().def_path_hash(def_id)
747 self.untracked.cstore.def_path_hash(def_id)
752 pub fn stable_crate_id(self, crate_num: CrateNum) -> StableCrateId {
753 if crate_num == LOCAL_CRATE {
754 self.sess.local_stable_crate_id()
756 self.untracked.cstore.stable_crate_id(crate_num)
760 /// Maps a StableCrateId to the corresponding CrateNum. This method assumes
761 /// that the crate in question has already been loaded by the CrateStore.
763 pub fn stable_crate_id_to_crate_num(self, stable_crate_id: StableCrateId) -> CrateNum {
764 if stable_crate_id == self.sess.local_stable_crate_id() {
767 self.untracked.cstore.stable_crate_id_to_crate_num(stable_crate_id)
771 /// Converts a `DefPathHash` to its corresponding `DefId` in the current compilation
772 /// session, if it still exists. This is used during incremental compilation to
773 /// turn a deserialized `DefPathHash` into its current `DefId`.
774 pub fn def_path_hash_to_def_id(self, hash: DefPathHash, err: &mut dyn FnMut() -> !) -> DefId {
775 debug!("def_path_hash_to_def_id({:?})", hash);
777 let stable_crate_id = hash.stable_crate_id();
779 // If this is a DefPathHash from the local crate, we can look up the
780 // DefId in the tcx's `Definitions`.
781 if stable_crate_id == self.sess.local_stable_crate_id() {
782 self.untracked.definitions.read().local_def_path_hash_to_def_id(hash, err).to_def_id()
784 // If this is a DefPathHash from an upstream crate, let the CrateStore map
786 let cstore = &*self.untracked.cstore;
787 let cnum = cstore.stable_crate_id_to_crate_num(stable_crate_id);
788 cstore.def_path_hash_to_def_id(cnum, hash)
792 pub fn def_path_debug_str(self, def_id: DefId) -> String {
793 // We are explicitly not going through queries here in order to get
794 // crate name and stable crate id since this code is called from debug!()
795 // statements within the query system and we'd run into endless
796 // recursion otherwise.
797 let (crate_name, stable_crate_id) = if def_id.is_local() {
798 (self.crate_name(LOCAL_CRATE), self.sess.local_stable_crate_id())
800 let cstore = &*self.untracked.cstore;
801 (cstore.crate_name(def_id.krate), cstore.stable_crate_id(def_id.krate))
807 // Don't print the whole stable crate id. That's just
808 // annoying in debug output.
809 stable_crate_id.to_u64() >> 8 * 6,
810 self.def_path(def_id).to_string_no_crate_verbose()
815 impl<'tcx> TyCtxtAt<'tcx> {
816 /// Create a new definition within the incr. comp. engine.
820 data: hir::definitions::DefPathData,
821 ) -> TyCtxtFeed<'tcx, LocalDefId> {
822 // This function modifies `self.definitions` using a side-effect.
823 // We need to ensure that these side effects are re-run by the incr. comp. engine.
824 // Depending on the forever-red node will tell the graph that the calling query
825 // needs to be re-evaluated.
826 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
828 // The following call has the side effect of modifying the tables inside `definitions`.
829 // These very tables are relied on by the incr. comp. engine to decode DepNodes and to
830 // decode the on-disk cache.
832 // Any LocalDefId which is used within queries, either as key or result, either:
833 // - has been created before the construction of the TyCtxt;
834 // - has been created by this call to `create_def`.
835 // As a consequence, this LocalDefId is always re-created before it is needed by the incr.
836 // comp. engine itself.
838 // This call also writes to the value of `source_span` and `expn_that_defined` queries.
839 // This is fine because:
840 // - those queries are `eval_always` so we won't miss their result changing;
841 // - this write will have happened before these queries are called.
842 let key = self.untracked.definitions.write().create_def(parent, data);
844 let feed = TyCtxtFeed { tcx: self.tcx, key };
845 feed.def_span(self.span);
850 impl<'tcx> TyCtxt<'tcx> {
851 pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> + 'tcx {
852 // Create a dependency to the red node to be sure we re-execute this when the amount of
853 // definitions change.
854 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
856 let definitions = &self.untracked.definitions;
857 std::iter::from_generator(|| {
860 // Recompute the number of definitions each time, because our caller may be creating
862 while i < { definitions.read().num_definitions() } {
863 let local_def_index = rustc_span::def_id::DefIndex::from_usize(i);
864 yield LocalDefId { local_def_index };
868 // Leak a read lock once we finish iterating on definitions, to prevent adding new ones.
873 pub fn def_path_table(self) -> &'tcx rustc_hir::definitions::DefPathTable {
874 // Create a dependency to the crate to be sure we re-execute this when the amount of
875 // definitions change.
876 self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
878 // Leak a read lock once we start iterating on definitions, to prevent adding new ones
879 // while iterating. If some query needs to add definitions, it should be `ensure`d above.
880 let definitions = self.untracked.definitions.leak();
881 definitions.def_path_table()
884 pub fn def_path_hash_to_def_index_map(
886 ) -> &'tcx rustc_hir::def_path_hash_map::DefPathHashMap {
887 // Create a dependency to the crate to be sure we re-execute this when the amount of
888 // definitions change.
889 self.ensure().hir_crate(());
890 // Leak a read lock once we start iterating on definitions, to prevent adding new ones
891 // while iterating. If some query needs to add definitions, it should be `ensure`d above.
892 let definitions = self.untracked.definitions.leak();
893 definitions.def_path_hash_to_def_index_map()
896 /// Note that this is *untracked* and should only be used within the query
897 /// system if the result is otherwise tracked through queries
898 pub fn cstore_untracked(self) -> &'tcx CrateStoreDyn {
899 &*self.untracked.cstore
902 /// Note that this is *untracked* and should only be used within the query
903 /// system if the result is otherwise tracked through queries
905 pub fn definitions_untracked(self) -> ReadGuard<'tcx, Definitions> {
906 self.untracked.definitions.read()
909 /// Note that this is *untracked* and should only be used within the query
910 /// system if the result is otherwise tracked through queries
912 pub fn source_span_untracked(self, def_id: LocalDefId) -> Span {
913 self.untracked.source_span.get(def_id).copied().unwrap_or(DUMMY_SP)
917 pub fn with_stable_hashing_context<R>(
919 f: impl FnOnce(StableHashingContext<'_>) -> R,
921 f(StableHashingContext::new(self.sess, &self.untracked))
924 pub fn serialize_query_result_cache(self, encoder: FileEncoder) -> FileEncodeResult {
925 self.on_disk_cache.as_ref().map_or(Ok(0), |c| c.serialize(self, encoder))
928 /// If `true`, we should use lazy normalization for constants, otherwise
929 /// we still evaluate them eagerly.
931 pub fn lazy_normalization(self) -> bool {
932 let features = self.features();
933 // Note: We only use lazy normalization for generic const expressions.
934 features.generic_const_exprs
938 pub fn local_crate_exports_generics(self) -> bool {
939 debug_assert!(self.sess.opts.share_generics());
941 self.sess.crate_types().iter().any(|crate_type| {
943 CrateType::Executable
944 | CrateType::Staticlib
945 | CrateType::ProcMacro
946 | CrateType::Cdylib => false,
948 // FIXME rust-lang/rust#64319, rust-lang/rust#64872:
949 // We want to block export of generics from dylibs,
950 // but we must fix rust-lang/rust#65890 before we can
952 CrateType::Dylib => true,
954 CrateType::Rlib => true,
959 /// Returns the `DefId` and the `BoundRegionKind` corresponding to the given region.
960 pub fn is_suitable_region(self, region: Region<'tcx>) -> Option<FreeRegionInfo> {
961 let (suitable_region_binding_scope, bound_region) = match *region {
962 ty::ReFree(ref free_region) => {
963 (free_region.scope.expect_local(), free_region.bound_region)
965 ty::ReEarlyBound(ref ebr) => (
966 self.local_parent(ebr.def_id.expect_local()),
967 ty::BoundRegionKind::BrNamed(ebr.def_id, ebr.name),
969 _ => return None, // not a free region
972 let is_impl_item = match self.hir().find_by_def_id(suitable_region_binding_scope) {
973 Some(Node::Item(..) | Node::TraitItem(..)) => false,
974 Some(Node::ImplItem(..)) => {
975 self.is_bound_region_in_impl_item(suitable_region_binding_scope)
980 Some(FreeRegionInfo {
981 def_id: suitable_region_binding_scope,
982 boundregion: bound_region,
987 /// Given a `DefId` for an `fn`, return all the `dyn` and `impl` traits in its return type.
988 pub fn return_type_impl_or_dyn_traits(
990 scope_def_id: LocalDefId,
991 ) -> Vec<&'tcx hir::Ty<'tcx>> {
992 let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
993 let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id) else {
997 let mut v = TraitObjectVisitor(vec![], self.hir());
998 v.visit_ty(hir_output);
1002 pub fn return_type_impl_trait(self, scope_def_id: LocalDefId) -> Option<(Ty<'tcx>, Span)> {
1003 // `type_of()` will fail on these (#55796, #86483), so only allow `fn`s or closures.
1004 match self.hir().get_by_def_id(scope_def_id) {
1005 Node::Item(&hir::Item { kind: ItemKind::Fn(..), .. }) => {}
1006 Node::TraitItem(&hir::TraitItem { kind: TraitItemKind::Fn(..), .. }) => {}
1007 Node::ImplItem(&hir::ImplItem { kind: ImplItemKind::Fn(..), .. }) => {}
1008 Node::Expr(&hir::Expr { kind: ExprKind::Closure { .. }, .. }) => {}
1012 let ret_ty = self.type_of(scope_def_id);
1013 match ret_ty.kind() {
1014 ty::FnDef(_, _) => {
1015 let sig = ret_ty.fn_sig(self);
1016 let output = self.erase_late_bound_regions(sig.output());
1017 if output.is_impl_trait() {
1018 let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
1019 let fn_decl = self.hir().fn_decl_by_hir_id(hir_id).unwrap();
1020 Some((output, fn_decl.output.span()))
1029 /// Checks if the bound region is in Impl Item.
1030 pub fn is_bound_region_in_impl_item(self, suitable_region_binding_scope: LocalDefId) -> bool {
1031 let container_id = self.parent(suitable_region_binding_scope.to_def_id());
1032 if self.impl_trait_ref(container_id).is_some() {
1033 // For now, we do not try to target impls of traits. This is
1034 // because this message is going to suggest that the user
1035 // change the fn signature, but they may not be free to do so,
1036 // since the signature must match the trait.
1038 // FIXME(#42706) -- in some cases, we could do better here.
1044 /// Determines whether identifiers in the assembly have strict naming rules.
1045 /// Currently, only NVPTX* targets need it.
1046 pub fn has_strict_asm_symbol_naming(self) -> bool {
1047 self.sess.target.arch.contains("nvptx")
1050 /// Returns `&'static core::panic::Location<'static>`.
1051 pub fn caller_location_ty(self) -> Ty<'tcx> {
1053 self.lifetimes.re_static,
1054 self.bound_type_of(self.require_lang_item(LangItem::PanicLocation, None))
1055 .subst(self, self.mk_substs([self.lifetimes.re_static.into()].iter())),
1059 /// Returns a displayable description and article for the given `def_id` (e.g. `("a", "struct")`).
1060 pub fn article_and_description(self, def_id: DefId) -> (&'static str, &'static str) {
1061 match self.def_kind(def_id) {
1062 DefKind::Generator => match self.generator_kind(def_id).unwrap() {
1063 rustc_hir::GeneratorKind::Async(..) => ("an", "async closure"),
1064 rustc_hir::GeneratorKind::Gen => ("a", "generator"),
1066 def_kind => (def_kind.article(), def_kind.descr(def_id)),
1070 pub fn type_length_limit(self) -> Limit {
1071 self.limits(()).type_length_limit
1074 pub fn recursion_limit(self) -> Limit {
1075 self.limits(()).recursion_limit
1078 pub fn move_size_limit(self) -> Limit {
1079 self.limits(()).move_size_limit
1082 pub fn const_eval_limit(self) -> Limit {
1083 if self.sess.opts.unstable_opts.tiny_const_eval_limit {
1084 TINY_CONST_EVAL_LIMIT
1086 self.limits(()).const_eval_limit
1090 pub fn all_traits(self) -> impl Iterator<Item = DefId> + 'tcx {
1091 iter::once(LOCAL_CRATE)
1092 .chain(self.crates(()).iter().copied())
1093 .flat_map(move |cnum| self.traits_in_crate(cnum).iter().copied())
1097 pub fn local_visibility(self, def_id: LocalDefId) -> Visibility {
1098 self.visibility(def_id).expect_local()
1102 /// A trait implemented for all `X<'a>` types that can be safely and
1103 /// efficiently converted to `X<'tcx>` as long as they are part of the
1104 /// provided `TyCtxt<'tcx>`.
1105 /// This can be done, for example, for `Ty<'tcx>` or `SubstsRef<'tcx>`
1106 /// by looking them up in their respective interners.
1108 /// However, this is still not the best implementation as it does
1109 /// need to compare the components, even for interned values.
1110 /// It would be more efficient if `TypedArena` provided a way to
1111 /// determine whether the address is in the allocated range.
1113 /// `None` is returned if the value or one of the components is not part
1114 /// of the provided context.
1115 /// For `Ty`, `None` can be returned if either the type interner doesn't
1116 /// contain the `TyKind` key or if the address of the interned
1117 /// pointer differs. The latter case is possible if a primitive type,
1118 /// e.g., `()` or `u8`, was interned in a different context.
1119 pub trait Lift<'tcx>: fmt::Debug {
1120 type Lifted: fmt::Debug + 'tcx;
1121 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted>;
1124 macro_rules! nop_lift {
1125 ($set:ident; $ty:ty => $lifted:ty) => {
1126 impl<'a, 'tcx> Lift<'tcx> for $ty {
1127 type Lifted = $lifted;
1128 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1129 if tcx.interners.$set.contains_pointer_to(&InternedInSet(&*self.0.0)) {
1130 // SAFETY: `self` is interned and therefore valid
1131 // for the entire lifetime of the `TyCtxt`.
1132 Some(unsafe { mem::transmute(self) })
1141 // Can't use the macros as we have reuse the `substs` here.
1143 // See `intern_type_list` for more info.
1144 impl<'a, 'tcx> Lift<'tcx> for &'a List<Ty<'a>> {
1145 type Lifted = &'tcx List<Ty<'tcx>>;
1146 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1147 if self.is_empty() {
1148 return Some(List::empty());
1150 if tcx.interners.substs.contains_pointer_to(&InternedInSet(self.as_substs())) {
1151 // SAFETY: `self` is interned and therefore valid
1152 // for the entire lifetime of the `TyCtxt`.
1153 Some(unsafe { mem::transmute::<&'a List<Ty<'a>>, &'tcx List<Ty<'tcx>>>(self) })
1160 macro_rules! nop_list_lift {
1161 ($set:ident; $ty:ty => $lifted:ty) => {
1162 impl<'a, 'tcx> Lift<'tcx> for &'a List<$ty> {
1163 type Lifted = &'tcx List<$lifted>;
1164 fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
1165 if self.is_empty() {
1166 return Some(List::empty());
1168 if tcx.interners.$set.contains_pointer_to(&InternedInSet(self)) {
1169 Some(unsafe { mem::transmute(self) })
1178 nop_lift! {type_; Ty<'a> => Ty<'tcx>}
1179 nop_lift! {region; Region<'a> => Region<'tcx>}
1180 nop_lift! {const_; Const<'a> => Const<'tcx>}
1181 nop_lift! {const_allocation; ConstAllocation<'a> => ConstAllocation<'tcx>}
1182 nop_lift! {predicate; Predicate<'a> => Predicate<'tcx>}
1184 nop_list_lift! {poly_existential_predicates; PolyExistentialPredicate<'a> => PolyExistentialPredicate<'tcx>}
1185 nop_list_lift! {predicates; Predicate<'a> => Predicate<'tcx>}
1186 nop_list_lift! {canonical_var_infos; CanonicalVarInfo<'a> => CanonicalVarInfo<'tcx>}
1187 nop_list_lift! {projs; ProjectionKind => ProjectionKind}
1188 nop_list_lift! {bound_variable_kinds; ty::BoundVariableKind => ty::BoundVariableKind}
1190 // This is the impl for `&'a InternalSubsts<'a>`.
1191 nop_list_lift! {substs; GenericArg<'a> => GenericArg<'tcx>}
1193 CloneLiftImpls! { for<'tcx> {
1194 Constness, traits::WellFormedLoc, ImplPolarity, crate::mir::ReturnConstraint,
1198 use super::{ptr_eq, GlobalCtxt, TyCtxt};
1200 use crate::dep_graph::TaskDepsRef;
1201 use crate::ty::query;
1202 use rustc_data_structures::sync::{self, Lock};
1203 use rustc_errors::Diagnostic;
1205 use thin_vec::ThinVec;
1207 #[cfg(not(parallel_compiler))]
1208 use std::cell::Cell;
1210 #[cfg(parallel_compiler)]
1211 use rustc_rayon_core as rayon_core;
1213 /// This is the implicit state of rustc. It contains the current
1214 /// `TyCtxt` and query. It is updated when creating a local interner or
1215 /// executing a new query. Whenever there's a `TyCtxt` value available
1216 /// you should also have access to an `ImplicitCtxt` through the functions
1219 pub struct ImplicitCtxt<'a, 'tcx> {
1220 /// The current `TyCtxt`.
1221 pub tcx: TyCtxt<'tcx>,
1223 /// The current query job, if any. This is updated by `JobOwner::start` in
1224 /// `ty::query::plumbing` when executing a query.
1225 pub query: Option<query::QueryJobId>,
1227 /// Where to store diagnostics for the current query job, if any.
1228 /// This is updated by `JobOwner::start` in `ty::query::plumbing` when executing a query.
1229 pub diagnostics: Option<&'a Lock<ThinVec<Diagnostic>>>,
1231 /// Used to prevent queries from calling too deeply.
1232 pub query_depth: usize,
1234 /// The current dep graph task. This is used to add dependencies to queries
1235 /// when executing them.
1236 pub task_deps: TaskDepsRef<'a>,
1239 impl<'a, 'tcx> ImplicitCtxt<'a, 'tcx> {
1240 pub fn new(gcx: &'tcx GlobalCtxt<'tcx>) -> Self {
1241 let tcx = TyCtxt { gcx };
1247 task_deps: TaskDepsRef::Ignore,
1252 /// Sets Rayon's thread-local variable, which is preserved for Rayon jobs
1253 /// to `value` during the call to `f`. It is restored to its previous value after.
1254 /// This is used to set the pointer to the new `ImplicitCtxt`.
1255 #[cfg(parallel_compiler)]
1257 fn set_tlv<F: FnOnce() -> R, R>(value: usize, f: F) -> R {
1258 rayon_core::tlv::with(value, f)
1261 /// Gets Rayon's thread-local variable, which is preserved for Rayon jobs.
1262 /// This is used to get the pointer to the current `ImplicitCtxt`.
1263 #[cfg(parallel_compiler)]
1265 pub fn get_tlv() -> usize {
1266 rayon_core::tlv::get()
1269 #[cfg(not(parallel_compiler))]
1271 /// A thread local variable that stores a pointer to the current `ImplicitCtxt`.
1272 static TLV: Cell<usize> = const { Cell::new(0) };
1275 /// Sets TLV to `value` during the call to `f`.
1276 /// It is restored to its previous value after.
1277 /// This is used to set the pointer to the new `ImplicitCtxt`.
1278 #[cfg(not(parallel_compiler))]
1280 fn set_tlv<F: FnOnce() -> R, R>(value: usize, f: F) -> R {
1281 let old = get_tlv();
1282 let _reset = rustc_data_structures::OnDrop(move || TLV.with(|tlv| tlv.set(old)));
1283 TLV.with(|tlv| tlv.set(value));
1287 /// Gets the pointer to the current `ImplicitCtxt`.
1288 #[cfg(not(parallel_compiler))]
1290 fn get_tlv() -> usize {
1291 TLV.with(|tlv| tlv.get())
1294 /// Sets `context` as the new current `ImplicitCtxt` for the duration of the function `f`.
1296 pub fn enter_context<'a, 'tcx, F, R>(context: &ImplicitCtxt<'a, 'tcx>, f: F) -> R
1298 F: FnOnce(&ImplicitCtxt<'a, 'tcx>) -> R,
1300 set_tlv(context as *const _ as usize, || f(&context))
1303 /// Allows access to the current `ImplicitCtxt` in a closure if one is available.
1305 pub fn with_context_opt<F, R>(f: F) -> R
1307 F: for<'a, 'tcx> FnOnce(Option<&ImplicitCtxt<'a, 'tcx>>) -> R,
1309 let context = get_tlv();
1313 // We could get an `ImplicitCtxt` pointer from another thread.
1314 // Ensure that `ImplicitCtxt` is `Sync`.
1315 sync::assert_sync::<ImplicitCtxt<'_, '_>>();
1317 unsafe { f(Some(&*(context as *const ImplicitCtxt<'_, '_>))) }
1321 /// Allows access to the current `ImplicitCtxt`.
1322 /// Panics if there is no `ImplicitCtxt` available.
1324 pub fn with_context<F, R>(f: F) -> R
1326 F: for<'a, 'tcx> FnOnce(&ImplicitCtxt<'a, 'tcx>) -> R,
1328 with_context_opt(|opt_context| f(opt_context.expect("no ImplicitCtxt stored in tls")))
1331 /// Allows access to the current `ImplicitCtxt` whose tcx field is the same as the tcx argument
1332 /// passed in. This means the closure is given an `ImplicitCtxt` with the same `'tcx` lifetime
1333 /// as the `TyCtxt` passed in.
1334 /// This will panic if you pass it a `TyCtxt` which is different from the current
1335 /// `ImplicitCtxt`'s `tcx` field.
1337 pub fn with_related_context<'tcx, F, R>(tcx: TyCtxt<'tcx>, f: F) -> R
1339 F: FnOnce(&ImplicitCtxt<'_, 'tcx>) -> R,
1341 with_context(|context| unsafe {
1342 assert!(ptr_eq(context.tcx.gcx, tcx.gcx));
1343 let context: &ImplicitCtxt<'_, '_> = mem::transmute(context);
1348 /// Allows access to the `TyCtxt` in the current `ImplicitCtxt`.
1349 /// Panics if there is no `ImplicitCtxt` available.
1351 pub fn with<F, R>(f: F) -> R
1353 F: for<'tcx> FnOnce(TyCtxt<'tcx>) -> R,
1355 with_context(|context| f(context.tcx))
1358 /// Allows access to the `TyCtxt` in the current `ImplicitCtxt`.
1359 /// The closure is passed None if there is no `ImplicitCtxt` available.
1361 pub fn with_opt<F, R>(f: F) -> R
1363 F: for<'tcx> FnOnce(Option<TyCtxt<'tcx>>) -> R,
1365 with_context_opt(|opt_context| f(opt_context.map(|context| context.tcx)))
1369 macro_rules! sty_debug_print {
1370 ($fmt: expr, $ctxt: expr, $($variant: ident),*) => {{
1371 // Curious inner module to allow variant names to be used as
1373 #[allow(non_snake_case)]
1375 use crate::ty::{self, TyCtxt};
1376 use crate::ty::context::InternedInSet;
1378 #[derive(Copy, Clone)]
1387 pub fn go(fmt: &mut std::fmt::Formatter<'_>, tcx: TyCtxt<'_>) -> std::fmt::Result {
1388 let mut total = DebugStat {
1395 $(let mut $variant = total;)*
1397 let shards = tcx.interners.type_.lock_shards();
1398 let types = shards.iter().flat_map(|shard| shard.keys());
1399 for &InternedInSet(t) in types {
1400 let variant = match t.internee {
1401 ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
1402 ty::Float(..) | ty::Str | ty::Never => continue,
1403 ty::Error(_) => /* unimportant */ continue,
1404 $(ty::$variant(..) => &mut $variant,)*
1406 let lt = t.flags.intersects(ty::TypeFlags::HAS_RE_INFER);
1407 let ty = t.flags.intersects(ty::TypeFlags::HAS_TY_INFER);
1408 let ct = t.flags.intersects(ty::TypeFlags::HAS_CT_INFER);
1412 if lt { total.lt_infer += 1; variant.lt_infer += 1 }
1413 if ty { total.ty_infer += 1; variant.ty_infer += 1 }
1414 if ct { total.ct_infer += 1; variant.ct_infer += 1 }
1415 if lt && ty && ct { total.all_infer += 1; variant.all_infer += 1 }
1417 writeln!(fmt, "Ty interner total ty lt ct all")?;
1418 $(writeln!(fmt, " {:18}: {uses:6} {usespc:4.1}%, \
1419 {ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
1420 stringify!($variant),
1421 uses = $variant.total,
1422 usespc = $variant.total as f64 * 100.0 / total.total as f64,
1423 ty = $variant.ty_infer as f64 * 100.0 / total.total as f64,
1424 lt = $variant.lt_infer as f64 * 100.0 / total.total as f64,
1425 ct = $variant.ct_infer as f64 * 100.0 / total.total as f64,
1426 all = $variant.all_infer as f64 * 100.0 / total.total as f64)?;
1428 writeln!(fmt, " total {uses:6} \
1429 {ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
1431 ty = total.ty_infer as f64 * 100.0 / total.total as f64,
1432 lt = total.lt_infer as f64 * 100.0 / total.total as f64,
1433 ct = total.ct_infer as f64 * 100.0 / total.total as f64,
1434 all = total.all_infer as f64 * 100.0 / total.total as f64)
1438 inner::go($fmt, $ctxt)
1442 impl<'tcx> TyCtxt<'tcx> {
1443 pub fn debug_stats(self) -> impl std::fmt::Debug + 'tcx {
1444 struct DebugStats<'tcx>(TyCtxt<'tcx>);
1446 impl<'tcx> std::fmt::Debug for DebugStats<'tcx> {
1447 fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
1471 writeln!(fmt, "InternalSubsts interner: #{}", self.0.interners.substs.len())?;
1472 writeln!(fmt, "Region interner: #{}", self.0.interners.region.len())?;
1475 "Const Allocation interner: #{}",
1476 self.0.interners.const_allocation.len()
1478 writeln!(fmt, "Layout interner: #{}", self.0.interners.layout.len())?;
1488 // This type holds a `T` in the interner. The `T` is stored in the arena and
1489 // this type just holds a pointer to it, but it still effectively owns it. It
1490 // impls `Borrow` so that it can be looked up using the original
1491 // (non-arena-memory-owning) types.
1492 struct InternedInSet<'tcx, T: ?Sized>(&'tcx T);
1494 impl<'tcx, T: 'tcx + ?Sized> Clone for InternedInSet<'tcx, T> {
1495 fn clone(&self) -> Self {
1496 InternedInSet(self.0)
1500 impl<'tcx, T: 'tcx + ?Sized> Copy for InternedInSet<'tcx, T> {}
1502 impl<'tcx, T: 'tcx + ?Sized> IntoPointer for InternedInSet<'tcx, T> {
1503 fn into_pointer(&self) -> *const () {
1504 self.0 as *const _ as *const ()
1508 #[allow(rustc::usage_of_ty_tykind)]
1509 impl<'tcx, T> Borrow<T> for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1510 fn borrow(&self) -> &T {
1515 impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1516 fn eq(&self, other: &InternedInSet<'tcx, WithCachedTypeInfo<T>>) -> bool {
1517 // The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
1519 self.0.internee == other.0.internee
1523 impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {}
1525 impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
1526 fn hash<H: Hasher>(&self, s: &mut H) {
1527 // The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
1528 self.0.internee.hash(s)
1532 impl<'tcx, T> Borrow<[T]> for InternedInSet<'tcx, List<T>> {
1533 fn borrow(&self) -> &[T] {
1538 impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, List<T>> {
1539 fn eq(&self, other: &InternedInSet<'tcx, List<T>>) -> bool {
1540 // The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
1542 self.0[..] == other.0[..]
1546 impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, List<T>> {}
1548 impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, List<T>> {
1549 fn hash<H: Hasher>(&self, s: &mut H) {
1550 // The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
1555 macro_rules! direct_interners {
1556 ($($name:ident: $method:ident($ty:ty): $ret_ctor:ident -> $ret_ty:ty,)+) => {
1557 $(impl<'tcx> Borrow<$ty> for InternedInSet<'tcx, $ty> {
1558 fn borrow<'a>(&'a self) -> &'a $ty {
1563 impl<'tcx> PartialEq for InternedInSet<'tcx, $ty> {
1564 fn eq(&self, other: &Self) -> bool {
1565 // The `Borrow` trait requires that `x.borrow() == y.borrow()`
1571 impl<'tcx> Eq for InternedInSet<'tcx, $ty> {}
1573 impl<'tcx> Hash for InternedInSet<'tcx, $ty> {
1574 fn hash<H: Hasher>(&self, s: &mut H) {
1575 // The `Borrow` trait requires that `x.borrow().hash(s) ==
1581 impl<'tcx> TyCtxt<'tcx> {
1582 pub fn $method(self, v: $ty) -> $ret_ty {
1583 $ret_ctor(Interned::new_unchecked(self.interners.$name.intern(v, |v| {
1584 InternedInSet(self.interners.arena.alloc(v))
1592 region: mk_region(RegionKind<'tcx>): Region -> Region<'tcx>,
1593 const_: mk_const_internal(ConstData<'tcx>): Const -> Const<'tcx>,
1594 const_allocation: intern_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
1595 layout: intern_layout(LayoutS<VariantIdx>): Layout -> Layout<'tcx>,
1596 adt_def: intern_adt_def(AdtDefData): AdtDef -> AdtDef<'tcx>,
1599 macro_rules! slice_interners {
1600 ($($field:ident: $method:ident($ty:ty)),+ $(,)?) => (
1601 impl<'tcx> TyCtxt<'tcx> {
1602 $(pub fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
1603 self.interners.$field.intern_ref(v, || {
1604 InternedInSet(List::from_arena(&*self.arena, v))
1612 const_lists: _intern_const_list(Const<'tcx>),
1613 substs: _intern_substs(GenericArg<'tcx>),
1614 canonical_var_infos: _intern_canonical_var_infos(CanonicalVarInfo<'tcx>),
1615 poly_existential_predicates:
1616 _intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
1617 predicates: _intern_predicates(Predicate<'tcx>),
1618 projs: _intern_projs(ProjectionKind),
1619 place_elems: _intern_place_elems(PlaceElem<'tcx>),
1620 bound_variable_kinds: _intern_bound_variable_kinds(ty::BoundVariableKind),
1623 impl<'tcx> TyCtxt<'tcx> {
1624 /// Given a `fn` type, returns an equivalent `unsafe fn` type;
1625 /// that is, a `fn` type that is equivalent in every way for being
1627 pub fn safe_to_unsafe_fn_ty(self, sig: PolyFnSig<'tcx>) -> Ty<'tcx> {
1628 assert_eq!(sig.unsafety(), hir::Unsafety::Normal);
1629 self.mk_fn_ptr(sig.map_bound(|sig| ty::FnSig { unsafety: hir::Unsafety::Unsafe, ..sig }))
1632 /// Given the def_id of a Trait `trait_def_id` and the name of an associated item `assoc_name`
1633 /// returns true if the `trait_def_id` defines an associated item of name `assoc_name`.
1634 pub fn trait_may_define_assoc_type(self, trait_def_id: DefId, assoc_name: Ident) -> bool {
1635 self.super_traits_of(trait_def_id).any(|trait_did| {
1636 self.associated_items(trait_did)
1637 .find_by_name_and_kind(self, assoc_name, ty::AssocKind::Type, trait_did)
1642 /// Given a `ty`, return whether it's an `impl Future<...>`.
1643 pub fn ty_is_opaque_future(self, ty: Ty<'_>) -> bool {
1644 let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = ty.kind() else { return false };
1645 let future_trait = self.require_lang_item(LangItem::Future, None);
1647 self.explicit_item_bounds(def_id).iter().any(|(predicate, _)| {
1648 let ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) = predicate.kind().skip_binder() else {
1651 trait_predicate.trait_ref.def_id == future_trait
1652 && trait_predicate.polarity == ImplPolarity::Positive
1656 /// Computes the def-ids of the transitive supertraits of `trait_def_id`. This (intentionally)
1657 /// does not compute the full elaborated super-predicates but just the set of def-ids. It is used
1658 /// to identify which traits may define a given associated type to help avoid cycle errors.
1659 /// Returns a `DefId` iterator.
1660 fn super_traits_of(self, trait_def_id: DefId) -> impl Iterator<Item = DefId> + 'tcx {
1661 let mut set = FxHashSet::default();
1662 let mut stack = vec![trait_def_id];
1664 set.insert(trait_def_id);
1666 iter::from_fn(move || -> Option<DefId> {
1667 let trait_did = stack.pop()?;
1668 let generic_predicates = self.super_predicates_of(trait_did);
1670 for (predicate, _) in generic_predicates.predicates {
1671 if let ty::PredicateKind::Clause(ty::Clause::Trait(data)) =
1672 predicate.kind().skip_binder()
1674 if set.insert(data.def_id()) {
1675 stack.push(data.def_id());
1684 /// Given a closure signature, returns an equivalent fn signature. Detuples
1685 /// and so forth -- so e.g., if we have a sig with `Fn<(u32, i32)>` then
1686 /// you would get a `fn(u32, i32)`.
1687 /// `unsafety` determines the unsafety of the fn signature. If you pass
1688 /// `hir::Unsafety::Unsafe` in the previous example, then you would get
1689 /// an `unsafe fn (u32, i32)`.
1690 /// It cannot convert a closure that requires unsafe.
1691 pub fn signature_unclosure(
1693 sig: PolyFnSig<'tcx>,
1694 unsafety: hir::Unsafety,
1695 ) -> PolyFnSig<'tcx> {
1697 let params_iter = match s.inputs()[0].kind() {
1698 ty::Tuple(params) => params.into_iter(),
1701 self.mk_fn_sig(params_iter, s.output(), s.c_variadic, unsafety, abi::Abi::Rust)
1705 /// Same a `self.mk_region(kind)`, but avoids accessing the interners if
1708 pub fn reuse_or_mk_region(self, r: Region<'tcx>, kind: RegionKind<'tcx>) -> Region<'tcx> {
1709 if *r == kind { r } else { self.mk_region(kind) }
1712 #[allow(rustc::usage_of_ty_tykind)]
1714 pub fn mk_ty(self, st: TyKind<'tcx>) -> Ty<'tcx> {
1715 self.interners.intern_ty(
1718 // This is only used to create a stable hashing context.
1724 pub fn mk_predicate(self, binder: Binder<'tcx, PredicateKind<'tcx>>) -> Predicate<'tcx> {
1725 self.interners.intern_predicate(
1728 // This is only used to create a stable hashing context.
1734 pub fn reuse_or_mk_predicate(
1736 pred: Predicate<'tcx>,
1737 binder: Binder<'tcx, PredicateKind<'tcx>>,
1738 ) -> Predicate<'tcx> {
1739 if pred.kind() != binder { self.mk_predicate(binder) } else { pred }
1742 pub fn mk_mach_int(self, tm: IntTy) -> Ty<'tcx> {
1744 IntTy::Isize => self.types.isize,
1745 IntTy::I8 => self.types.i8,
1746 IntTy::I16 => self.types.i16,
1747 IntTy::I32 => self.types.i32,
1748 IntTy::I64 => self.types.i64,
1749 IntTy::I128 => self.types.i128,
1753 pub fn mk_mach_uint(self, tm: UintTy) -> Ty<'tcx> {
1755 UintTy::Usize => self.types.usize,
1756 UintTy::U8 => self.types.u8,
1757 UintTy::U16 => self.types.u16,
1758 UintTy::U32 => self.types.u32,
1759 UintTy::U64 => self.types.u64,
1760 UintTy::U128 => self.types.u128,
1764 pub fn mk_mach_float(self, tm: FloatTy) -> Ty<'tcx> {
1766 FloatTy::F32 => self.types.f32,
1767 FloatTy::F64 => self.types.f64,
1772 pub fn mk_static_str(self) -> Ty<'tcx> {
1773 self.mk_imm_ref(self.lifetimes.re_static, self.types.str_)
1777 pub fn mk_adt(self, def: AdtDef<'tcx>, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
1778 // Take a copy of substs so that we own the vectors inside.
1779 self.mk_ty(Adt(def, substs))
1783 pub fn mk_foreign(self, def_id: DefId) -> Ty<'tcx> {
1784 self.mk_ty(Foreign(def_id))
1787 fn mk_generic_adt(self, wrapper_def_id: DefId, ty_param: Ty<'tcx>) -> Ty<'tcx> {
1788 let adt_def = self.adt_def(wrapper_def_id);
1790 InternalSubsts::for_item(self, wrapper_def_id, |param, substs| match param.kind {
1791 GenericParamDefKind::Lifetime | GenericParamDefKind::Const { .. } => bug!(),
1792 GenericParamDefKind::Type { has_default, .. } => {
1793 if param.index == 0 {
1796 assert!(has_default);
1797 self.bound_type_of(param.def_id).subst(self, substs).into()
1801 self.mk_ty(Adt(adt_def, substs))
1805 pub fn mk_box(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1806 let def_id = self.require_lang_item(LangItem::OwnedBox, None);
1807 self.mk_generic_adt(def_id, ty)
1811 pub fn mk_lang_item(self, ty: Ty<'tcx>, item: LangItem) -> Option<Ty<'tcx>> {
1812 let def_id = self.lang_items().get(item)?;
1813 Some(self.mk_generic_adt(def_id, ty))
1817 pub fn mk_diagnostic_item(self, ty: Ty<'tcx>, name: Symbol) -> Option<Ty<'tcx>> {
1818 let def_id = self.get_diagnostic_item(name)?;
1819 Some(self.mk_generic_adt(def_id, ty))
1823 pub fn mk_maybe_uninit(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1824 let def_id = self.require_lang_item(LangItem::MaybeUninit, None);
1825 self.mk_generic_adt(def_id, ty)
1829 pub fn mk_ptr(self, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
1830 self.mk_ty(RawPtr(tm))
1834 pub fn mk_ref(self, r: Region<'tcx>, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
1835 self.mk_ty(Ref(r, tm.ty, tm.mutbl))
1839 pub fn mk_mut_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
1840 self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Mut })
1844 pub fn mk_imm_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
1845 self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Not })
1849 pub fn mk_mut_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1850 self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Mut })
1854 pub fn mk_imm_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1855 self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Not })
1859 pub fn mk_array(self, ty: Ty<'tcx>, n: u64) -> Ty<'tcx> {
1860 self.mk_ty(Array(ty, ty::Const::from_usize(self, n)))
1864 pub fn mk_slice(self, ty: Ty<'tcx>) -> Ty<'tcx> {
1865 self.mk_ty(Slice(ty))
1869 pub fn intern_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
1870 self.mk_ty(Tuple(self.intern_type_list(&ts)))
1873 pub fn mk_tup<I: InternAs<Ty<'tcx>, Ty<'tcx>>>(self, iter: I) -> I::Output {
1874 iter.intern_with(|ts| self.mk_ty(Tuple(self.intern_type_list(&ts))))
1878 pub fn mk_unit(self) -> Ty<'tcx> {
1883 pub fn mk_diverging_default(self) -> Ty<'tcx> {
1884 if self.features().never_type_fallback { self.types.never } else { self.types.unit }
1891 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1893 let substs = self.check_substs(def_id, substs);
1894 self.mk_ty(FnDef(def_id, substs))
1901 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1902 ) -> SubstsRef<'tcx> {
1903 let substs = substs.into_iter().map(Into::into);
1904 #[cfg(debug_assertions)]
1906 let n = self.generics_of(_def_id).count();
1910 "wrong number of generic parameters for {_def_id:?}: {:?}",
1911 substs.collect::<Vec<_>>(),
1914 self.mk_substs(substs)
1918 pub fn mk_fn_ptr(self, fty: PolyFnSig<'tcx>) -> Ty<'tcx> {
1919 self.mk_ty(FnPtr(fty))
1925 obj: &'tcx List<PolyExistentialPredicate<'tcx>>,
1926 reg: ty::Region<'tcx>,
1929 self.mk_ty(Dynamic(obj, reg, repr))
1933 pub fn mk_projection(
1936 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
1938 self.mk_ty(Alias(ty::Projection, self.mk_alias_ty(item_def_id, substs)))
1942 pub fn mk_closure(self, closure_id: DefId, closure_substs: SubstsRef<'tcx>) -> Ty<'tcx> {
1943 self.mk_ty(Closure(closure_id, closure_substs))
1947 pub fn mk_generator(
1950 generator_substs: SubstsRef<'tcx>,
1951 movability: hir::Movability,
1953 self.mk_ty(Generator(id, generator_substs, movability))
1957 pub fn mk_generator_witness(self, types: ty::Binder<'tcx, &'tcx List<Ty<'tcx>>>) -> Ty<'tcx> {
1958 self.mk_ty(GeneratorWitness(types))
1961 /// Creates a `&mut Context<'_>` [`Ty`] with erased lifetimes.
1962 pub fn mk_task_context(self) -> Ty<'tcx> {
1963 let context_did = self.require_lang_item(LangItem::Context, None);
1964 let context_adt_ref = self.adt_def(context_did);
1965 let context_substs = self.intern_substs(&[self.lifetimes.re_erased.into()]);
1966 let context_ty = self.mk_adt(context_adt_ref, context_substs);
1967 self.mk_mut_ref(self.lifetimes.re_erased, context_ty)
1971 pub fn mk_ty_var(self, v: TyVid) -> Ty<'tcx> {
1972 self.mk_ty_infer(TyVar(v))
1976 pub fn mk_const(self, kind: impl Into<ty::ConstKind<'tcx>>, ty: Ty<'tcx>) -> Const<'tcx> {
1977 self.mk_const_internal(ty::ConstData { kind: kind.into(), ty })
1981 pub fn mk_int_var(self, v: IntVid) -> Ty<'tcx> {
1982 self.mk_ty_infer(IntVar(v))
1986 pub fn mk_float_var(self, v: FloatVid) -> Ty<'tcx> {
1987 self.mk_ty_infer(FloatVar(v))
1991 pub fn mk_ty_infer(self, it: InferTy) -> Ty<'tcx> {
1992 self.mk_ty(Infer(it))
1996 pub fn mk_ty_param(self, index: u32, name: Symbol) -> Ty<'tcx> {
1997 self.mk_ty(Param(ParamTy { index, name }))
2000 pub fn mk_param_from_def(self, param: &ty::GenericParamDef) -> GenericArg<'tcx> {
2002 GenericParamDefKind::Lifetime => {
2003 self.mk_region(ty::ReEarlyBound(param.to_early_bound_region_data())).into()
2005 GenericParamDefKind::Type { .. } => self.mk_ty_param(param.index, param.name).into(),
2006 GenericParamDefKind::Const { .. } => self
2008 ParamConst { index: param.index, name: param.name },
2009 self.type_of(param.def_id),
2016 pub fn mk_opaque(self, def_id: DefId, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
2017 self.mk_ty(Alias(ty::Opaque, self.mk_alias_ty(def_id, substs)))
2020 pub fn mk_place_field(self, place: Place<'tcx>, f: Field, ty: Ty<'tcx>) -> Place<'tcx> {
2021 self.mk_place_elem(place, PlaceElem::Field(f, ty))
2024 pub fn mk_place_deref(self, place: Place<'tcx>) -> Place<'tcx> {
2025 self.mk_place_elem(place, PlaceElem::Deref)
2028 pub fn mk_place_downcast(
2031 adt_def: AdtDef<'tcx>,
2032 variant_index: VariantIdx,
2036 PlaceElem::Downcast(Some(adt_def.variant(variant_index).name), variant_index),
2040 pub fn mk_place_downcast_unnamed(
2043 variant_index: VariantIdx,
2045 self.mk_place_elem(place, PlaceElem::Downcast(None, variant_index))
2048 pub fn mk_place_index(self, place: Place<'tcx>, index: Local) -> Place<'tcx> {
2049 self.mk_place_elem(place, PlaceElem::Index(index))
2052 /// This method copies `Place`'s projection, add an element and reintern it. Should not be used
2053 /// to build a full `Place` it's just a convenient way to grab a projection and modify it in
2055 pub fn mk_place_elem(self, place: Place<'tcx>, elem: PlaceElem<'tcx>) -> Place<'tcx> {
2056 let mut projection = place.projection.to_vec();
2057 projection.push(elem);
2059 Place { local: place.local, projection: self.intern_place_elems(&projection) }
2062 pub fn intern_poly_existential_predicates(
2064 eps: &[PolyExistentialPredicate<'tcx>],
2065 ) -> &'tcx List<PolyExistentialPredicate<'tcx>> {
2066 assert!(!eps.is_empty());
2069 .all(|[a, b]| a.skip_binder().stable_cmp(self, &b.skip_binder())
2070 != Ordering::Greater)
2072 self._intern_poly_existential_predicates(eps)
2075 pub fn intern_predicates(self, preds: &[Predicate<'tcx>]) -> &'tcx List<Predicate<'tcx>> {
2076 // FIXME consider asking the input slice to be sorted to avoid
2077 // re-interning permutations, in which case that would be asserted
2079 if preds.is_empty() {
2080 // The macro-generated method below asserts we don't intern an empty slice.
2083 self._intern_predicates(preds)
2087 pub fn mk_const_list<I: InternAs<ty::Const<'tcx>, &'tcx List<ty::Const<'tcx>>>>(
2091 iter.intern_with(|xs| self.intern_const_list(xs))
2094 pub fn intern_const_list(self, cs: &[ty::Const<'tcx>]) -> &'tcx List<ty::Const<'tcx>> {
2095 if cs.is_empty() { List::empty() } else { self._intern_const_list(cs) }
2098 pub fn intern_type_list(self, ts: &[Ty<'tcx>]) -> &'tcx List<Ty<'tcx>> {
2102 // Actually intern type lists as lists of `GenericArg`s.
2104 // Transmuting from `Ty<'tcx>` to `GenericArg<'tcx>` is sound
2105 // as explained in ty_slice_as_generic_arg`. With this,
2106 // we guarantee that even when transmuting between `List<Ty<'tcx>>`
2107 // and `List<GenericArg<'tcx>>`, the uniqueness requirement for
2109 let substs = self._intern_substs(ty::subst::ty_slice_as_generic_args(ts));
2110 substs.try_as_type_list().unwrap()
2114 pub fn intern_substs(self, ts: &[GenericArg<'tcx>]) -> &'tcx List<GenericArg<'tcx>> {
2115 if ts.is_empty() { List::empty() } else { self._intern_substs(ts) }
2118 pub fn intern_projs(self, ps: &[ProjectionKind]) -> &'tcx List<ProjectionKind> {
2119 if ps.is_empty() { List::empty() } else { self._intern_projs(ps) }
2122 pub fn intern_place_elems(self, ts: &[PlaceElem<'tcx>]) -> &'tcx List<PlaceElem<'tcx>> {
2123 if ts.is_empty() { List::empty() } else { self._intern_place_elems(ts) }
2126 pub fn intern_canonical_var_infos(
2128 ts: &[CanonicalVarInfo<'tcx>],
2129 ) -> CanonicalVarInfos<'tcx> {
2130 if ts.is_empty() { List::empty() } else { self._intern_canonical_var_infos(ts) }
2133 pub fn intern_bound_variable_kinds(
2135 ts: &[ty::BoundVariableKind],
2136 ) -> &'tcx List<ty::BoundVariableKind> {
2137 if ts.is_empty() { List::empty() } else { self._intern_bound_variable_kinds(ts) }
2140 pub fn mk_fn_sig<I>(
2145 unsafety: hir::Unsafety,
2147 ) -> <I::Item as InternIteratorElement<Ty<'tcx>, ty::FnSig<'tcx>>>::Output
2149 I: Iterator<Item: InternIteratorElement<Ty<'tcx>, ty::FnSig<'tcx>>>,
2151 inputs.chain(iter::once(output)).intern_with(|xs| ty::FnSig {
2152 inputs_and_output: self.intern_type_list(xs),
2159 pub fn mk_poly_existential_predicates<
2160 I: InternAs<PolyExistentialPredicate<'tcx>, &'tcx List<PolyExistentialPredicate<'tcx>>>,
2165 iter.intern_with(|xs| self.intern_poly_existential_predicates(xs))
2168 pub fn mk_predicates<I: InternAs<Predicate<'tcx>, &'tcx List<Predicate<'tcx>>>>(
2172 iter.intern_with(|xs| self.intern_predicates(xs))
2175 pub fn mk_type_list<I: InternAs<Ty<'tcx>, &'tcx List<Ty<'tcx>>>>(self, iter: I) -> I::Output {
2176 iter.intern_with(|xs| self.intern_type_list(xs))
2179 pub fn mk_substs<I: InternAs<GenericArg<'tcx>, &'tcx List<GenericArg<'tcx>>>>(
2183 iter.intern_with(|xs| self.intern_substs(xs))
2186 pub fn mk_place_elems<I: InternAs<PlaceElem<'tcx>, &'tcx List<PlaceElem<'tcx>>>>(
2190 iter.intern_with(|xs| self.intern_place_elems(xs))
2193 pub fn mk_substs_trait(
2196 rest: impl IntoIterator<Item = GenericArg<'tcx>>,
2197 ) -> SubstsRef<'tcx> {
2198 self.mk_substs(iter::once(self_ty.into()).chain(rest))
2201 pub fn mk_trait_ref(
2203 trait_def_id: DefId,
2204 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
2205 ) -> ty::TraitRef<'tcx> {
2206 let substs = self.check_substs(trait_def_id, substs);
2207 ty::TraitRef { def_id: trait_def_id, substs, _use_mk_trait_ref_instead: () }
2213 substs: impl IntoIterator<Item = impl Into<GenericArg<'tcx>>>,
2214 ) -> ty::AliasTy<'tcx> {
2215 let substs = self.check_substs(def_id, substs);
2216 ty::AliasTy { def_id, substs, _use_mk_alias_ty_instead: () }
2219 pub fn mk_bound_variable_kinds<
2220 I: InternAs<ty::BoundVariableKind, &'tcx List<ty::BoundVariableKind>>,
2225 iter.intern_with(|xs| self.intern_bound_variable_kinds(xs))
2228 /// Emit a lint at `span` from a lint struct (some type that implements `DecorateLint`,
2229 /// typically generated by `#[derive(LintDiagnostic)]`).
2230 pub fn emit_spanned_lint(
2232 lint: &'static Lint,
2234 span: impl Into<MultiSpan>,
2235 decorator: impl for<'a> DecorateLint<'a, ()>,
2237 let msg = decorator.msg();
2238 let (level, src) = self.lint_level_at_node(lint, hir_id);
2239 struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, |diag| {
2240 decorator.decorate_lint(diag)
2244 /// Emit a lint at the appropriate level for a hir node, with an associated span.
2246 /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
2248 /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
2249 #[rustc_lint_diagnostics]
2250 pub fn struct_span_lint_hir(
2252 lint: &'static Lint,
2254 span: impl Into<MultiSpan>,
2255 msg: impl Into<DiagnosticMessage>,
2256 decorate: impl for<'a, 'b> FnOnce(
2257 &'b mut DiagnosticBuilder<'a, ()>,
2258 ) -> &'b mut DiagnosticBuilder<'a, ()>,
2260 let (level, src) = self.lint_level_at_node(lint, hir_id);
2261 struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, decorate);
2264 /// Emit a lint from a lint struct (some type that implements `DecorateLint`, typically
2265 /// generated by `#[derive(LintDiagnostic)]`).
2268 lint: &'static Lint,
2270 decorator: impl for<'a> DecorateLint<'a, ()>,
2272 self.struct_lint_node(lint, id, decorator.msg(), |diag| decorator.decorate_lint(diag))
2275 /// Emit a lint at the appropriate level for a hir node.
2277 /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
2279 /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
2280 #[rustc_lint_diagnostics]
2281 pub fn struct_lint_node(
2283 lint: &'static Lint,
2285 msg: impl Into<DiagnosticMessage>,
2286 decorate: impl for<'a, 'b> FnOnce(
2287 &'b mut DiagnosticBuilder<'a, ()>,
2288 ) -> &'b mut DiagnosticBuilder<'a, ()>,
2290 let (level, src) = self.lint_level_at_node(lint, id);
2291 struct_lint_level(self.sess, lint, level, src, None, msg, decorate);
2294 pub fn in_scope_traits(self, id: HirId) -> Option<&'tcx [TraitCandidate]> {
2295 let map = self.in_scope_traits_map(id.owner)?;
2296 let candidates = map.get(&id.local_id)?;
2300 pub fn named_region(self, id: HirId) -> Option<resolve_lifetime::Region> {
2301 debug!(?id, "named_region");
2302 self.named_region_map(id.owner).and_then(|map| map.get(&id.local_id).cloned())
2305 pub fn is_late_bound(self, id: HirId) -> bool {
2306 self.is_late_bound_map(id.owner.def_id).map_or(false, |set| {
2307 let def_id = self.hir().local_def_id(id);
2308 set.contains(&def_id)
2312 pub fn late_bound_vars(self, id: HirId) -> &'tcx List<ty::BoundVariableKind> {
2313 self.mk_bound_variable_kinds(
2314 self.late_bound_vars_map(id.owner)
2315 .and_then(|map| map.get(&id.local_id).cloned())
2316 .unwrap_or_else(|| {
2317 bug!("No bound vars found for {:?} ({:?})", self.hir().node_to_string(id), id)
2323 /// Whether the `def_id` counts as const fn in the current crate, considering all active
2325 pub fn is_const_fn(self, def_id: DefId) -> bool {
2326 if self.is_const_fn_raw(def_id) {
2327 match self.lookup_const_stability(def_id) {
2328 Some(stability) if stability.is_const_unstable() => {
2329 // has a `rustc_const_unstable` attribute, check whether the user enabled the
2330 // corresponding feature gate.
2332 .declared_lib_features
2334 .any(|&(sym, _)| sym == stability.feature)
2336 // functions without const stability are either stable user written
2337 // const fn or the user is using feature gates and we thus don't
2338 // care what they do
2346 /// Whether the trait impl is marked const. This does not consider stability or feature gates.
2347 pub fn is_const_trait_impl_raw(self, def_id: DefId) -> bool {
2348 let Some(local_def_id) = def_id.as_local() else { return false };
2349 let hir_id = self.local_def_id_to_hir_id(local_def_id);
2350 let node = self.hir().get(hir_id);
2354 hir::Node::Item(hir::Item {
2355 kind: hir::ItemKind::Impl(hir::Impl { constness: hir::Constness::Const, .. }),
2362 impl<'tcx> TyCtxtAt<'tcx> {
2363 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
2365 pub fn ty_error(self) -> Ty<'tcx> {
2366 self.tcx.ty_error_with_message(self.span, "TyKind::Error constructed but no error reported")
2369 /// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg to
2370 /// ensure it gets used.
2372 pub fn ty_error_with_message(self, msg: &str) -> Ty<'tcx> {
2373 self.tcx.ty_error_with_message(self.span, msg)
2376 pub fn mk_trait_ref(
2378 trait_lang_item: LangItem,
2379 substs: impl IntoIterator<Item = impl Into<ty::GenericArg<'tcx>>>,
2380 ) -> ty::TraitRef<'tcx> {
2381 let trait_def_id = self.require_lang_item(trait_lang_item, Some(self.span));
2382 self.tcx.mk_trait_ref(trait_def_id, substs)
2386 /// Parameter attributes that can only be determined by examining the body of a function instead
2387 /// of just its signature.
2389 /// These can be useful for optimization purposes when a function is directly called. We compute
2390 /// them and store them into the crate metadata so that downstream crates can make use of them.
2392 /// Right now, we only have `read_only`, but `no_capture` and `no_alias` might be useful in the
2394 #[derive(Clone, Copy, PartialEq, Debug, Default, TyDecodable, TyEncodable, HashStable)]
2395 pub struct DeducedParamAttrs {
2396 /// The parameter is marked immutable in the function and contains no `UnsafeCell` (i.e. its
2397 /// type is freeze).
2398 pub read_only: bool,
2401 // We are comparing types with different invariant lifetimes, so `ptr::eq`
2402 // won't work for us.
2403 fn ptr_eq<T, U>(t: *const T, u: *const U) -> bool {
2404 t as *const () == u as *const ()
2407 pub fn provide(providers: &mut ty::query::Providers) {
2408 providers.module_reexports =
2409 |tcx, id| tcx.resolutions(()).reexport_map.get(&id).map(|v| &v[..]);
2410 providers.maybe_unused_trait_imports =
2411 |tcx, ()| &tcx.resolutions(()).maybe_unused_trait_imports;
2412 providers.maybe_unused_extern_crates =
2413 |tcx, ()| &tcx.resolutions(()).maybe_unused_extern_crates[..];
2414 providers.names_imported_by_glob_use = |tcx, id| {
2415 tcx.arena.alloc(tcx.resolutions(()).glob_map.get(&id).cloned().unwrap_or_default())
2418 providers.extern_mod_stmt_cnum =
2419 |tcx, id| tcx.resolutions(()).extern_crate_map.get(&id).cloned();
2420 providers.is_panic_runtime = |tcx, cnum| {
2421 assert_eq!(cnum, LOCAL_CRATE);
2422 tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::panic_runtime)
2424 providers.is_compiler_builtins = |tcx, cnum| {
2425 assert_eq!(cnum, LOCAL_CRATE);
2426 tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::compiler_builtins)
2428 providers.has_panic_handler = |tcx, cnum| {
2429 assert_eq!(cnum, LOCAL_CRATE);
2430 // We want to check if the panic handler was defined in this crate
2431 tcx.lang_items().panic_impl().map_or(false, |did| did.is_local())
2433 providers.source_span =
2434 |tcx, def_id| tcx.untracked.source_span.get(def_id).copied().unwrap_or(DUMMY_SP);