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fuchsia / third_party / rust / 9a86ceb049380a2a684b7bc8fd6c76235f51d9d1 / . / compiler / rustc_middle / src / ty / context.rs
blob: 8aea2d8aedf982aeb936247069f5ee966fd32e02 [file] [log] [blame]
//! Type context book-keeping.
#![allow(rustc::usage_of_ty_tykind)]
pub mod tls;
use crate::arena::Arena;
use crate::dep_graph::{DepGraph, DepKindStruct};
use crate::infer::canonical::CanonicalVarInfo;
use crate::lint::struct_lint_level;
use crate::metadata::ModChild;
use crate::middle::codegen_fn_attrs::CodegenFnAttrs;
use crate::middle::resolve_bound_vars;
use crate::middle::stability;
use crate::mir::interpret::{self, Allocation, ConstAllocation};
use crate::mir::{Body, Local, Place, PlaceElem, ProjectionKind, Promoted};
use crate::query::on_disk_cache::OnDiskCache;
use crate::query::LocalCrate;
use crate::thir::Thir;
use crate::traits;
use crate::traits::solve;
use crate::traits::solve::{ExternalConstraints, ExternalConstraintsData};
use crate::ty::query::QuerySystem;
use crate::ty::query::QuerySystemFns;
use crate::ty::query::{self, TyCtxtAt};
use crate::ty::{
self, AdtDef, AdtDefData, AdtKind, Binder, Const, ConstData, FloatTy, FloatVar, FloatVid,
GenericParamDefKind, ImplPolarity, InferTy, IntTy, IntVar, IntVid, List, ParamConst, ParamTy,
PolyExistentialPredicate, PolyFnSig, Predicate, PredicateKind, Region, RegionKind, ReprOptions,
TraitObjectVisitor, Ty, TyKind, TyVar, TyVid, TypeAndMut, UintTy, Visibility,
};
use crate::ty::{GenericArg, InternalSubsts, SubstsRef};
use rustc_ast::{self as ast, attr};
use rustc_data_structures::fingerprint::Fingerprint;
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
use rustc_data_structures::intern::Interned;
use rustc_data_structures::profiling::SelfProfilerRef;
use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc_data_structures::steal::Steal;
use rustc_data_structures::sync::{self, Lock, Lrc, MappedReadGuard, ReadGuard, WorkerLocal};
use rustc_data_structures::unord::UnordSet;
use rustc_errors::{
DecorateLint, DiagnosticBuilder, DiagnosticMessage, ErrorGuaranteed, MultiSpan,
};
use rustc_hir as hir;
use rustc_hir::def::DefKind;
use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LOCAL_CRATE};
use rustc_hir::definitions::Definitions;
use rustc_hir::intravisit::Visitor;
use rustc_hir::lang_items::LangItem;
use rustc_hir::{
Constness, ExprKind, HirId, ImplItemKind, ItemKind, Node, TraitCandidate, TraitItemKind,
};
use rustc_index::IndexVec;
use rustc_macros::HashStable;
use rustc_query_system::dep_graph::DepNodeIndex;
use rustc_query_system::ich::StableHashingContext;
use rustc_serialize::opaque::{FileEncodeResult, FileEncoder};
use rustc_session::config::CrateType;
use rustc_session::cstore::{CrateStoreDyn, Untracked};
use rustc_session::lint::Lint;
use rustc_session::Limit;
use rustc_session::Session;
use rustc_span::def_id::{DefPathHash, StableCrateId};
use rustc_span::symbol::{kw, sym, Ident, Symbol};
use rustc_span::{Span, DUMMY_SP};
use rustc_target::abi::{FieldIdx, Layout, LayoutS, TargetDataLayout, VariantIdx};
use rustc_target::spec::abi;
use rustc_type_ir::sty::TyKind::*;
use rustc_type_ir::WithCachedTypeInfo;
use rustc_type_ir::{CollectAndApply, DynKind, Interner, TypeFlags};
use std::any::Any;
use std::assert_matches::debug_assert_matches;
use std::borrow::Borrow;
use std::cmp::Ordering;
use std::fmt;
use std::hash::{Hash, Hasher};
use std::iter;
use std::mem;
use std::ops::{Bound, Deref};
use super::query::IntoQueryParam;
const TINY_CONST_EVAL_LIMIT: Limit = Limit(20);
#[allow(rustc::usage_of_ty_tykind)]
impl<'tcx> Interner for TyCtxt<'tcx> {
type AdtDef = ty::AdtDef<'tcx>;
type SubstsRef = ty::SubstsRef<'tcx>;
type DefId = DefId;
type Binder<T> = Binder<'tcx, T>;
type Ty = Ty<'tcx>;
type Const = ty::Const<'tcx>;
type Region = Region<'tcx>;
type Predicate = Predicate<'tcx>;
type TypeAndMut = TypeAndMut<'tcx>;
type Mutability = hir::Mutability;
type Movability = hir::Movability;
type PolyFnSig = PolyFnSig<'tcx>;
type ListBinderExistentialPredicate = &'tcx List<PolyExistentialPredicate<'tcx>>;
type BinderListTy = Binder<'tcx, &'tcx List<Ty<'tcx>>>;
type ListTy = &'tcx List<Ty<'tcx>>;
type AliasTy = ty::AliasTy<'tcx>;
type ParamTy = ParamTy;
type BoundTy = ty::BoundTy;
type PlaceholderType = ty::PlaceholderType;
type InferTy = InferTy;
type ErrorGuaranteed = ErrorGuaranteed;
type PredicateKind = ty::PredicateKind<'tcx>;
type AllocId = crate::mir::interpret::AllocId;
type EarlyBoundRegion = ty::EarlyBoundRegion;
type BoundRegion = ty::BoundRegion;
type FreeRegion = ty::FreeRegion;
type RegionVid = ty::RegionVid;
type PlaceholderRegion = ty::PlaceholderRegion;
}
type InternedSet<'tcx, T> = ShardedHashMap<InternedInSet<'tcx, T>, ()>;
pub struct CtxtInterners<'tcx> {
/// The arena that types, regions, etc. are allocated from.
arena: &'tcx WorkerLocal<Arena<'tcx>>,
// Specifically use a speedy hash algorithm for these hash sets, since
// they're accessed quite often.
type_: InternedSet<'tcx, WithCachedTypeInfo<TyKind<'tcx>>>,
const_lists: InternedSet<'tcx, List<ty::Const<'tcx>>>,
substs: InternedSet<'tcx, InternalSubsts<'tcx>>,
type_lists: InternedSet<'tcx, List<Ty<'tcx>>>,
canonical_var_infos: InternedSet<'tcx, List<CanonicalVarInfo<'tcx>>>,
region: InternedSet<'tcx, RegionKind<'tcx>>,
poly_existential_predicates: InternedSet<'tcx, List<PolyExistentialPredicate<'tcx>>>,
predicate: InternedSet<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>,
predicates: InternedSet<'tcx, List<Predicate<'tcx>>>,
projs: InternedSet<'tcx, List<ProjectionKind>>,
place_elems: InternedSet<'tcx, List<PlaceElem<'tcx>>>,
const_: InternedSet<'tcx, ConstData<'tcx>>,
const_allocation: InternedSet<'tcx, Allocation>,
bound_variable_kinds: InternedSet<'tcx, List<ty::BoundVariableKind>>,
layout: InternedSet<'tcx, LayoutS>,
adt_def: InternedSet<'tcx, AdtDefData>,
external_constraints: InternedSet<'tcx, ExternalConstraintsData<'tcx>>,
fields: InternedSet<'tcx, List<FieldIdx>>,
}
impl<'tcx> CtxtInterners<'tcx> {
fn new(arena: &'tcx WorkerLocal<Arena<'tcx>>) -> CtxtInterners<'tcx> {
CtxtInterners {
arena,
type_: Default::default(),
const_lists: Default::default(),
substs: Default::default(),
type_lists: Default::default(),
region: Default::default(),
poly_existential_predicates: Default::default(),
canonical_var_infos: Default::default(),
predicate: Default::default(),
predicates: Default::default(),
projs: Default::default(),
place_elems: Default::default(),
const_: Default::default(),
const_allocation: Default::default(),
bound_variable_kinds: Default::default(),
layout: Default::default(),
adt_def: Default::default(),
external_constraints: Default::default(),
fields: Default::default(),
}
}
/// Interns a type. (Use `mk_*` functions instead, where possible.)
#[allow(rustc::usage_of_ty_tykind)]
#[inline(never)]
fn intern_ty(&self, kind: TyKind<'tcx>, sess: &Session, untracked: &Untracked) -> Ty<'tcx> {
Ty(Interned::new_unchecked(
self.type_
.intern(kind, |kind| {
let flags = super::flags::FlagComputation::for_kind(&kind);
let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
InternedInSet(self.arena.alloc(WithCachedTypeInfo {
internee: kind,
stable_hash,
flags: flags.flags,
outer_exclusive_binder: flags.outer_exclusive_binder,
}))
})
.0,
))
}
fn stable_hash<'a, T: HashStable<StableHashingContext<'a>>>(
&self,
flags: &ty::flags::FlagComputation,
sess: &'a Session,
untracked: &'a Untracked,
val: &T,
) -> Fingerprint {
// It's impossible to hash inference variables (and will ICE), so we don't need to try to cache them.
// Without incremental, we rarely stable-hash types, so let's not do it proactively.
if flags.flags.intersects(TypeFlags::HAS_INFER) || sess.opts.incremental.is_none() {
Fingerprint::ZERO
} else {
let mut hasher = StableHasher::new();
let mut hcx = StableHashingContext::new(sess, untracked);
val.hash_stable(&mut hcx, &mut hasher);
hasher.finish()
}
}
/// Interns a predicate. (Use `mk_predicate` instead, where possible.)
#[inline(never)]
fn intern_predicate(
&self,
kind: Binder<'tcx, PredicateKind<'tcx>>,
sess: &Session,
untracked: &Untracked,
) -> Predicate<'tcx> {
Predicate(Interned::new_unchecked(
self.predicate
.intern(kind, |kind| {
let flags = super::flags::FlagComputation::for_predicate(kind);
let stable_hash = self.stable_hash(&flags, sess, untracked, &kind);
InternedInSet(self.arena.alloc(WithCachedTypeInfo {
internee: kind,
stable_hash,
flags: flags.flags,
outer_exclusive_binder: flags.outer_exclusive_binder,
}))
})
.0,
))
}
}
// For these preinterned values, an alternative would be to have
// variable-length vectors that grow as needed. But that turned out to be
// slightly more complex and no faster.
const NUM_PREINTERNED_TY_VARS: u32 = 100;
const NUM_PREINTERNED_FRESH_TYS: u32 = 20;
const NUM_PREINTERNED_FRESH_INT_TYS: u32 = 3;
const NUM_PREINTERNED_FRESH_FLOAT_TYS: u32 = 3;
// This number may seem high, but it is reached in all but the smallest crates.
const NUM_PREINTERNED_RE_VARS: u32 = 500;
const NUM_PREINTERNED_RE_LATE_BOUNDS_I: u32 = 2;
const NUM_PREINTERNED_RE_LATE_BOUNDS_V: u32 = 20;
pub struct CommonTypes<'tcx> {
pub unit: Ty<'tcx>,
pub bool: Ty<'tcx>,
pub char: Ty<'tcx>,
pub isize: Ty<'tcx>,
pub i8: Ty<'tcx>,
pub i16: Ty<'tcx>,
pub i32: Ty<'tcx>,
pub i64: Ty<'tcx>,
pub i128: Ty<'tcx>,
pub usize: Ty<'tcx>,
pub u8: Ty<'tcx>,
pub u16: Ty<'tcx>,
pub u32: Ty<'tcx>,
pub u64: Ty<'tcx>,
pub u128: Ty<'tcx>,
pub f32: Ty<'tcx>,
pub f64: Ty<'tcx>,
pub str_: Ty<'tcx>,
pub never: Ty<'tcx>,
pub self_param: Ty<'tcx>,
/// Dummy type used for the `Self` of a `TraitRef` created for converting
/// a trait object, and which gets removed in `ExistentialTraitRef`.
/// This type must not appear anywhere in other converted types.
/// `Infer(ty::FreshTy(0))` does the job.
pub trait_object_dummy_self: Ty<'tcx>,
/// Pre-interned `Infer(ty::TyVar(n))` for small values of `n`.
pub ty_vars: Vec<Ty<'tcx>>,
/// Pre-interned `Infer(ty::FreshTy(n))` for small values of `n`.
pub fresh_tys: Vec<Ty<'tcx>>,
/// Pre-interned `Infer(ty::FreshIntTy(n))` for small values of `n`.
pub fresh_int_tys: Vec<Ty<'tcx>>,
/// Pre-interned `Infer(ty::FreshFloatTy(n))` for small values of `n`.
pub fresh_float_tys: Vec<Ty<'tcx>>,
}
pub struct CommonLifetimes<'tcx> {
/// `ReStatic`
pub re_static: Region<'tcx>,
/// Erased region, used outside of type inference.
pub re_erased: Region<'tcx>,
/// Pre-interned `ReVar(ty::RegionVar(n))` for small values of `n`.
pub re_vars: Vec<Region<'tcx>>,
/// Pre-interned values of the form:
/// `ReLateBound(DebruijnIndex(i), BoundRegion { var: v, kind: BrAnon(None) })`
/// for small values of `i` and `v`.
pub re_late_bounds: Vec<Vec<Region<'tcx>>>,
}
pub struct CommonConsts<'tcx> {
pub unit: Const<'tcx>,
}
impl<'tcx> CommonTypes<'tcx> {
fn new(
interners: &CtxtInterners<'tcx>,
sess: &Session,
untracked: &Untracked,
) -> CommonTypes<'tcx> {
let mk = |ty| interners.intern_ty(ty, sess, untracked);
let ty_vars =
(0..NUM_PREINTERNED_TY_VARS).map(|n| mk(Infer(ty::TyVar(TyVid::from(n))))).collect();
let fresh_tys: Vec<_> =
(0..NUM_PREINTERNED_FRESH_TYS).map(|n| mk(Infer(ty::FreshTy(n)))).collect();
let fresh_int_tys: Vec<_> =
(0..NUM_PREINTERNED_FRESH_INT_TYS).map(|n| mk(Infer(ty::FreshIntTy(n)))).collect();
let fresh_float_tys: Vec<_> =
(0..NUM_PREINTERNED_FRESH_FLOAT_TYS).map(|n| mk(Infer(ty::FreshFloatTy(n)))).collect();
CommonTypes {
unit: mk(Tuple(List::empty())),
bool: mk(Bool),
char: mk(Char),
never: mk(Never),
isize: mk(Int(ty::IntTy::Isize)),
i8: mk(Int(ty::IntTy::I8)),
i16: mk(Int(ty::IntTy::I16)),
i32: mk(Int(ty::IntTy::I32)),
i64: mk(Int(ty::IntTy::I64)),
i128: mk(Int(ty::IntTy::I128)),
usize: mk(Uint(ty::UintTy::Usize)),
u8: mk(Uint(ty::UintTy::U8)),
u16: mk(Uint(ty::UintTy::U16)),
u32: mk(Uint(ty::UintTy::U32)),
u64: mk(Uint(ty::UintTy::U64)),
u128: mk(Uint(ty::UintTy::U128)),
f32: mk(Float(ty::FloatTy::F32)),
f64: mk(Float(ty::FloatTy::F64)),
str_: mk(Str),
self_param: mk(ty::Param(ty::ParamTy { index: 0, name: kw::SelfUpper })),
trait_object_dummy_self: fresh_tys[0],
ty_vars,
fresh_tys,
fresh_int_tys,
fresh_float_tys,
}
}
}
impl<'tcx> CommonLifetimes<'tcx> {
fn new(interners: &CtxtInterners<'tcx>) -> CommonLifetimes<'tcx> {
let mk = |r| {
Region(Interned::new_unchecked(
interners.region.intern(r, |r| InternedInSet(interners.arena.alloc(r))).0,
))
};
let re_vars =
(0..NUM_PREINTERNED_RE_VARS).map(|n| mk(ty::ReVar(ty::RegionVid::from(n)))).collect();
let re_late_bounds = (0..NUM_PREINTERNED_RE_LATE_BOUNDS_I)
.map(|i| {
(0..NUM_PREINTERNED_RE_LATE_BOUNDS_V)
.map(|v| {
mk(ty::ReLateBound(
ty::DebruijnIndex::from(i),
ty::BoundRegion { var: ty::BoundVar::from(v), kind: ty::BrAnon(None) },
))
})
.collect()
})
.collect();
CommonLifetimes {
re_static: mk(ty::ReStatic),
re_erased: mk(ty::ReErased),
re_vars,
re_late_bounds,
}
}
}
impl<'tcx> CommonConsts<'tcx> {
fn new(interners: &CtxtInterners<'tcx>, types: &CommonTypes<'tcx>) -> CommonConsts<'tcx> {
let mk_const = |c| {
Const(Interned::new_unchecked(
interners.const_.intern(c, |c| InternedInSet(interners.arena.alloc(c))).0,
))
};
CommonConsts {
unit: mk_const(ty::ConstData {
kind: ty::ConstKind::Value(ty::ValTree::zst()),
ty: types.unit,
}),
}
}
}
/// This struct contains information regarding the `ReFree(FreeRegion)` corresponding to a lifetime
/// conflict.
#[derive(Debug)]
pub struct FreeRegionInfo {
/// `LocalDefId` corresponding to FreeRegion
pub def_id: LocalDefId,
/// the bound region corresponding to FreeRegion
pub boundregion: ty::BoundRegionKind,
/// checks if bound region is in Impl Item
pub is_impl_item: bool,
}
/// This struct should only be created by `create_def`.
#[derive(Copy, Clone)]
pub struct TyCtxtFeed<'tcx, KEY: Copy> {
pub tcx: TyCtxt<'tcx>,
// Do not allow direct access, as downstream code must not mutate this field.
key: KEY,
}
impl<'tcx> TyCtxt<'tcx> {
pub fn feed_unit_query(self) -> TyCtxtFeed<'tcx, ()> {
TyCtxtFeed { tcx: self, key: () }
}
pub fn feed_local_crate(self) -> TyCtxtFeed<'tcx, CrateNum> {
TyCtxtFeed { tcx: self, key: LOCAL_CRATE }
}
/// In order to break cycles involving `AnonConst`, we need to set the expected type by side
/// effect. However, we do not want this as a general capability, so this interface restricts
/// to the only allowed case.
pub fn feed_anon_const_type(self, key: LocalDefId, value: ty::EarlyBinder<Ty<'tcx>>) {
debug_assert_eq!(self.def_kind(key), DefKind::AnonConst);
TyCtxtFeed { tcx: self, key }.type_of(value)
}
}
impl<'tcx, KEY: Copy> TyCtxtFeed<'tcx, KEY> {
#[inline(always)]
pub fn key(&self) -> KEY {
self.key
}
}
impl<'tcx> TyCtxtFeed<'tcx, LocalDefId> {
#[inline(always)]
pub fn def_id(&self) -> LocalDefId {
self.key
}
}
/// The central data structure of the compiler. It stores references
/// to the various **arenas** and also houses the results of the
/// various **compiler queries** that have been performed. See the
/// [rustc dev guide] for more details.
///
/// [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/ty.html
#[derive(Copy, Clone)]
#[rustc_diagnostic_item = "TyCtxt"]
#[rustc_pass_by_value]
pub struct TyCtxt<'tcx> {
gcx: &'tcx GlobalCtxt<'tcx>,
}
impl<'tcx> Deref for TyCtxt<'tcx> {
type Target = &'tcx GlobalCtxt<'tcx>;
#[inline(always)]
fn deref(&self) -> &Self::Target {
&self.gcx
}
}
pub struct GlobalCtxt<'tcx> {
pub arena: &'tcx WorkerLocal<Arena<'tcx>>,
pub hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
interners: CtxtInterners<'tcx>,
pub sess: &'tcx Session,
/// This only ever stores a `LintStore` but we don't want a dependency on that type here.
///
/// FIXME(Centril): consider `dyn LintStoreMarker` once
/// we can upcast to `Any` for some additional type safety.
pub lint_store: Lrc<dyn Any + sync::Sync + sync::Send>,
pub dep_graph: DepGraph,
pub prof: SelfProfilerRef,
/// Common types, pre-interned for your convenience.
pub types: CommonTypes<'tcx>,
/// Common lifetimes, pre-interned for your convenience.
pub lifetimes: CommonLifetimes<'tcx>,
/// Common consts, pre-interned for your convenience.
pub consts: CommonConsts<'tcx>,
untracked: Untracked,
pub query_system: query::QuerySystem<'tcx>,
pub(crate) query_kinds: &'tcx [DepKindStruct<'tcx>],
// Internal caches for metadata decoding. No need to track deps on this.
pub ty_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
pub pred_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Predicate<'tcx>>>,
/// Caches the results of trait selection. This cache is used
/// for things that do not have to do with the parameters in scope.
pub selection_cache: traits::SelectionCache<'tcx>,
/// Caches the results of trait evaluation. This cache is used
/// for things that do not have to do with the parameters in scope.
/// Merge this with `selection_cache`?
pub evaluation_cache: traits::EvaluationCache<'tcx>,
/// Caches the results of goal evaluation in the new solver.
pub new_solver_evaluation_cache: solve::EvaluationCache<'tcx>,
/// Data layout specification for the current target.
pub data_layout: TargetDataLayout,
/// Stores memory for globals (statics/consts).
pub(crate) alloc_map: Lock<interpret::AllocMap<'tcx>>,
}
impl<'tcx> GlobalCtxt<'tcx> {
/// Installs `self` in a `TyCtxt` and `ImplicitCtxt` for the duration of
/// `f`.
pub fn enter<'a: 'tcx, F, R>(&'a self, f: F) -> R
where
F: FnOnce(TyCtxt<'tcx>) -> R,
{
let icx = tls::ImplicitCtxt::new(self);
tls::enter_context(&icx, || f(icx.tcx))
}
}
impl<'tcx> TyCtxt<'tcx> {
/// Expects a body and returns its codegen attributes.
///
/// Unlike `codegen_fn_attrs`, this returns `CodegenFnAttrs::EMPTY` for
/// constants.
pub fn body_codegen_attrs(self, def_id: DefId) -> &'tcx CodegenFnAttrs {
let def_kind = self.def_kind(def_id);
if def_kind.has_codegen_attrs() {
self.codegen_fn_attrs(def_id)
} else if matches!(
def_kind,
DefKind::AnonConst | DefKind::AssocConst | DefKind::Const | DefKind::InlineConst
) {
CodegenFnAttrs::EMPTY
} else {
bug!(
"body_codegen_fn_attrs called on unexpected definition: {:?} {:?}",
def_id,
def_kind
)
}
}
pub fn alloc_steal_thir(self, thir: Thir<'tcx>) -> &'tcx Steal<Thir<'tcx>> {
self.arena.alloc(Steal::new(thir))
}
pub fn alloc_steal_mir(self, mir: Body<'tcx>) -> &'tcx Steal<Body<'tcx>> {
self.arena.alloc(Steal::new(mir))
}
pub fn alloc_steal_promoted(
self,
promoted: IndexVec<Promoted, Body<'tcx>>,
) -> &'tcx Steal<IndexVec<Promoted, Body<'tcx>>> {
self.arena.alloc(Steal::new(promoted))
}
pub fn mk_adt_def(
self,
did: DefId,
kind: AdtKind,
variants: IndexVec<VariantIdx, ty::VariantDef>,
repr: ReprOptions,
) -> ty::AdtDef<'tcx> {
self.mk_adt_def_from_data(ty::AdtDefData::new(self, did, kind, variants, repr))
}
/// Allocates a read-only byte or string literal for `mir::interpret`.
pub fn allocate_bytes(self, bytes: &[u8]) -> interpret::AllocId {
// Create an allocation that just contains these bytes.
let alloc = interpret::Allocation::from_bytes_byte_aligned_immutable(bytes);
let alloc = self.mk_const_alloc(alloc);
self.create_memory_alloc(alloc)
}
/// Returns a range of the start/end indices specified with the
/// `rustc_layout_scalar_valid_range` attribute.
// FIXME(eddyb) this is an awkward spot for this method, maybe move it?
pub fn layout_scalar_valid_range(self, def_id: DefId) -> (Bound<u128>, Bound<u128>) {
let get = |name| {
let Some(attr) = self.get_attr(def_id, name) else {
return Bound::Unbounded;
};
debug!("layout_scalar_valid_range: attr={:?}", attr);
if let Some(
&[
ast::NestedMetaItem::Lit(ast::MetaItemLit {
kind: ast::LitKind::Int(a, _),
..
}),
],
) = attr.meta_item_list().as_deref()
{
Bound::Included(a)
} else {
self.sess
.delay_span_bug(attr.span, "invalid rustc_layout_scalar_valid_range attribute");
Bound::Unbounded
}
};
(
get(sym::rustc_layout_scalar_valid_range_start),
get(sym::rustc_layout_scalar_valid_range_end),
)
}
pub fn lift<T: Lift<'tcx>>(self, value: T) -> Option<T::Lifted> {
value.lift_to_tcx(self)
}
/// Creates a type context and call the closure with a `TyCtxt` reference
/// to the context. The closure enforces that the type context and any interned
/// value (types, substs, etc.) can only be used while `ty::tls` has a valid
/// reference to the context, to allow formatting values that need it.
pub fn create_global_ctxt(
s: &'tcx Session,
lint_store: Lrc<dyn Any + sync::Send + sync::Sync>,
arena: &'tcx WorkerLocal<Arena<'tcx>>,
hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
untracked: Untracked,
dep_graph: DepGraph,
on_disk_cache: Option<OnDiskCache<'tcx>>,
query_kinds: &'tcx [DepKindStruct<'tcx>],
query_system_fns: QuerySystemFns<'tcx>,
) -> GlobalCtxt<'tcx> {
let data_layout = s.target.parse_data_layout().unwrap_or_else(|err| {
s.emit_fatal(err);
});
let interners = CtxtInterners::new(arena);
let common_types = CommonTypes::new(&interners, s, &untracked);
let common_lifetimes = CommonLifetimes::new(&interners);
let common_consts = CommonConsts::new(&interners, &common_types);
GlobalCtxt {
sess: s,
lint_store,
arena,
hir_arena,
interners,
dep_graph,
prof: s.prof.clone(),
types: common_types,
lifetimes: common_lifetimes,
consts: common_consts,
untracked,
query_system: QuerySystem::new(query_system_fns, on_disk_cache),
query_kinds,
ty_rcache: Default::default(),
pred_rcache: Default::default(),
selection_cache: Default::default(),
evaluation_cache: Default::default(),
new_solver_evaluation_cache: Default::default(),
data_layout,
alloc_map: Lock::new(interpret::AllocMap::new()),
}
}
/// Constructs a `TyKind::Error` type with current `ErrorGuaranteed`
#[track_caller]
pub fn ty_error(self, reported: ErrorGuaranteed) -> Ty<'tcx> {
self.mk_ty_from_kind(Error(reported))
}
/// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
#[track_caller]
pub fn ty_error_misc(self) -> Ty<'tcx> {
self.ty_error_with_message(DUMMY_SP, "TyKind::Error constructed but no error reported")
}
/// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg` to
/// ensure it gets used.
#[track_caller]
pub fn ty_error_with_message<S: Into<MultiSpan>>(self, span: S, msg: &str) -> Ty<'tcx> {
let reported = self.sess.delay_span_bug(span, msg);
self.mk_ty_from_kind(Error(reported))
}
/// Constructs a `RegionKind::ReError` lifetime.
#[track_caller]
pub fn mk_re_error(self, reported: ErrorGuaranteed) -> Region<'tcx> {
self.intern_region(ty::ReError(reported))
}
/// Constructs a `RegionKind::ReError` lifetime and registers a `delay_span_bug` to ensure it
/// gets used.
#[track_caller]
pub fn mk_re_error_misc(self) -> Region<'tcx> {
self.mk_re_error_with_message(
DUMMY_SP,
"RegionKind::ReError constructed but no error reported",
)
}
/// Constructs a `RegionKind::ReError` lifetime and registers a `delay_span_bug` with the given
/// `msg` to ensure it gets used.
#[track_caller]
pub fn mk_re_error_with_message<S: Into<MultiSpan>>(self, span: S, msg: &str) -> Region<'tcx> {
let reported = self.sess.delay_span_bug(span, msg);
self.mk_re_error(reported)
}
/// Like [TyCtxt::ty_error] but for constants, with current `ErrorGuaranteed`
#[track_caller]
pub fn const_error_with_guaranteed(
self,
ty: Ty<'tcx>,
reported: ErrorGuaranteed,
) -> Const<'tcx> {
self.mk_const(ty::ConstKind::Error(reported), ty)
}
/// Like [TyCtxt::ty_error] but for constants.
#[track_caller]
pub fn const_error(self, ty: Ty<'tcx>) -> Const<'tcx> {
self.const_error_with_message(
ty,
DUMMY_SP,
"ty::ConstKind::Error constructed but no error reported",
)
}
/// Like [TyCtxt::ty_error_with_message] but for constants.
#[track_caller]
pub fn const_error_with_message<S: Into<MultiSpan>>(
self,
ty: Ty<'tcx>,
span: S,
msg: &str,
) -> Const<'tcx> {
let reported = self.sess.delay_span_bug(span, msg);
self.mk_const(ty::ConstKind::Error(reported), ty)
}
pub fn consider_optimizing<T: Fn() -> String>(self, msg: T) -> bool {
self.sess.consider_optimizing(|| self.crate_name(LOCAL_CRATE), msg)
}
/// Obtain all lang items of this crate and all dependencies (recursively)
pub fn lang_items(self) -> &'tcx rustc_hir::lang_items::LanguageItems {
self.get_lang_items(())
}
/// Obtain the given diagnostic item's `DefId`. Use `is_diagnostic_item` if you just want to
/// compare against another `DefId`, since `is_diagnostic_item` is cheaper.
pub fn get_diagnostic_item(self, name: Symbol) -> Option<DefId> {
self.all_diagnostic_items(()).name_to_id.get(&name).copied()
}
/// Obtain the diagnostic item's name
pub fn get_diagnostic_name(self, id: DefId) -> Option<Symbol> {
self.diagnostic_items(id.krate).id_to_name.get(&id).copied()
}
/// Check whether the diagnostic item with the given `name` has the given `DefId`.
pub fn is_diagnostic_item(self, name: Symbol, did: DefId) -> bool {
self.diagnostic_items(did.krate).name_to_id.get(&name) == Some(&did)
}
/// Returns `true` if the node pointed to by `def_id` is a generator for an async construct.
pub fn generator_is_async(self, def_id: DefId) -> bool {
matches!(self.generator_kind(def_id), Some(hir::GeneratorKind::Async(_)))
}
pub fn stability(self) -> &'tcx stability::Index {
self.stability_index(())
}
pub fn features(self) -> &'tcx rustc_feature::Features {
self.features_query(())
}
pub fn def_key(self, id: impl IntoQueryParam<DefId>) -> rustc_hir::definitions::DefKey {
let id = id.into_query_param();
// Accessing the DefKey is ok, since it is part of DefPathHash.
if let Some(id) = id.as_local() {
self.definitions_untracked().def_key(id)
} else {
self.cstore_untracked().def_key(id)
}
}
/// Converts a `DefId` into its fully expanded `DefPath` (every
/// `DefId` is really just an interned `DefPath`).
///
/// Note that if `id` is not local to this crate, the result will
/// be a non-local `DefPath`.
pub fn def_path(self, id: DefId) -> rustc_hir::definitions::DefPath {
// Accessing the DefPath is ok, since it is part of DefPathHash.
if let Some(id) = id.as_local() {
self.definitions_untracked().def_path(id)
} else {
self.cstore_untracked().def_path(id)
}
}
#[inline]
pub fn def_path_hash(self, def_id: DefId) -> rustc_hir::definitions::DefPathHash {
// Accessing the DefPathHash is ok, it is incr. comp. stable.
if let Some(def_id) = def_id.as_local() {
self.definitions_untracked().def_path_hash(def_id)
} else {
self.cstore_untracked().def_path_hash(def_id)
}
}
#[inline]
pub fn stable_crate_id(self, crate_num: CrateNum) -> StableCrateId {
if crate_num == LOCAL_CRATE {
self.sess.local_stable_crate_id()
} else {
self.cstore_untracked().stable_crate_id(crate_num)
}
}
/// Maps a StableCrateId to the corresponding CrateNum. This method assumes
/// that the crate in question has already been loaded by the CrateStore.
#[inline]
pub fn stable_crate_id_to_crate_num(self, stable_crate_id: StableCrateId) -> CrateNum {
if stable_crate_id == self.sess.local_stable_crate_id() {
LOCAL_CRATE
} else {
self.cstore_untracked().stable_crate_id_to_crate_num(stable_crate_id)
}
}
/// Converts a `DefPathHash` to its corresponding `DefId` in the current compilation
/// session, if it still exists. This is used during incremental compilation to
/// turn a deserialized `DefPathHash` into its current `DefId`.
pub fn def_path_hash_to_def_id(self, hash: DefPathHash, err: &mut dyn FnMut() -> !) -> DefId {
debug!("def_path_hash_to_def_id({:?})", hash);
let stable_crate_id = hash.stable_crate_id();
// If this is a DefPathHash from the local crate, we can look up the
// DefId in the tcx's `Definitions`.
if stable_crate_id == self.sess.local_stable_crate_id() {
self.untracked.definitions.read().local_def_path_hash_to_def_id(hash, err).to_def_id()
} else {
// If this is a DefPathHash from an upstream crate, let the CrateStore map
// it to a DefId.
let cstore = &*self.cstore_untracked();
let cnum = cstore.stable_crate_id_to_crate_num(stable_crate_id);
cstore.def_path_hash_to_def_id(cnum, hash)
}
}
pub fn def_path_debug_str(self, def_id: DefId) -> String {
// We are explicitly not going through queries here in order to get
// crate name and stable crate id since this code is called from debug!()
// statements within the query system and we'd run into endless
// recursion otherwise.
let (crate_name, stable_crate_id) = if def_id.is_local() {
(self.crate_name(LOCAL_CRATE), self.sess.local_stable_crate_id())
} else {
let cstore = &*self.cstore_untracked();
(cstore.crate_name(def_id.krate), cstore.stable_crate_id(def_id.krate))
};
format!(
"{}[{:04x}]{}",
crate_name,
// Don't print the whole stable crate id. That's just
// annoying in debug output.
stable_crate_id.as_u64() >> (8 * 6),
self.def_path(def_id).to_string_no_crate_verbose()
)
}
}
impl<'tcx> TyCtxtAt<'tcx> {
/// Create a new definition within the incr. comp. engine.
pub fn create_def(
self,
parent: LocalDefId,
data: hir::definitions::DefPathData,
) -> TyCtxtFeed<'tcx, LocalDefId> {
// This function modifies `self.definitions` using a side-effect.
// We need to ensure that these side effects are re-run by the incr. comp. engine.
// Depending on the forever-red node will tell the graph that the calling query
// needs to be re-evaluated.
self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
// The following call has the side effect of modifying the tables inside `definitions`.
// These very tables are relied on by the incr. comp. engine to decode DepNodes and to
// decode the on-disk cache.
//
// Any LocalDefId which is used within queries, either as key or result, either:
// - has been created before the construction of the TyCtxt;
// - has been created by this call to `create_def`.
// As a consequence, this LocalDefId is always re-created before it is needed by the incr.
// comp. engine itself.
//
// This call also writes to the value of `source_span` and `expn_that_defined` queries.
// This is fine because:
// - those queries are `eval_always` so we won't miss their result changing;
// - this write will have happened before these queries are called.
let key = self.untracked.definitions.write().create_def(parent, data);
let feed = TyCtxtFeed { tcx: self.tcx, key };
feed.def_span(self.span);
feed
}
}
impl<'tcx> TyCtxt<'tcx> {
pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> + 'tcx {
// Create a dependency to the red node to be sure we re-execute this when the amount of
// definitions change.
self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
let definitions = &self.untracked.definitions;
std::iter::from_generator(|| {
let mut i = 0;
// Recompute the number of definitions each time, because our caller may be creating
// new ones.
while i < { definitions.read().num_definitions() } {
let local_def_index = rustc_span::def_id::DefIndex::from_usize(i);
yield LocalDefId { local_def_index };
i += 1;
}
// Leak a read lock once we finish iterating on definitions, to prevent adding new ones.
definitions.leak();
})
}
pub fn def_path_table(self) -> &'tcx rustc_hir::definitions::DefPathTable {
// Create a dependency to the crate to be sure we re-execute this when the amount of
// definitions change.
self.dep_graph.read_index(DepNodeIndex::FOREVER_RED_NODE);
// Leak a read lock once we start iterating on definitions, to prevent adding new ones
// while iterating. If some query needs to add definitions, it should be `ensure`d above.
let definitions = self.untracked.definitions.leak();
definitions.def_path_table()
}
pub fn def_path_hash_to_def_index_map(
self,
) -> &'tcx rustc_hir::def_path_hash_map::DefPathHashMap {
// Create a dependency to the crate to be sure we re-execute this when the amount of
// definitions change.
self.ensure().hir_crate(());
// Leak a read lock once we start iterating on definitions, to prevent adding new ones
// while iterating. If some query needs to add definitions, it should be `ensure`d above.
let definitions = self.untracked.definitions.leak();
definitions.def_path_hash_to_def_index_map()
}
/// Note that this is *untracked* and should only be used within the query
/// system if the result is otherwise tracked through queries
#[inline]
pub fn cstore_untracked(self) -> MappedReadGuard<'tcx, CrateStoreDyn> {
ReadGuard::map(self.untracked.cstore.read(), |c| &**c)
}
/// Give out access to the untracked data without any sanity checks.
pub fn untracked(self) -> &'tcx Untracked {
&self.untracked
}
/// Note that this is *untracked* and should only be used within the query
/// system if the result is otherwise tracked through queries
#[inline]
pub fn definitions_untracked(self) -> ReadGuard<'tcx, Definitions> {
self.untracked.definitions.read()
}
/// Note that this is *untracked* and should only be used within the query
/// system if the result is otherwise tracked through queries
#[inline]
pub fn source_span_untracked(self, def_id: LocalDefId) -> Span {
self.untracked.source_span.get(def_id).unwrap_or(DUMMY_SP)
}
#[inline(always)]
pub fn with_stable_hashing_context<R>(
self,
f: impl FnOnce(StableHashingContext<'_>) -> R,
) -> R {
f(StableHashingContext::new(self.sess, &self.untracked))
}
pub fn serialize_query_result_cache(self, encoder: FileEncoder) -> FileEncodeResult {
self.query_system.on_disk_cache.as_ref().map_or(Ok(0), |c| c.serialize(self, encoder))
}
/// If `true`, we should use lazy normalization for constants, otherwise
/// we still evaluate them eagerly.
#[inline]
pub fn lazy_normalization(self) -> bool {
let features = self.features();
// Note: We only use lazy normalization for generic const expressions.
features.generic_const_exprs
}
#[inline]
pub fn local_crate_exports_generics(self) -> bool {
debug_assert!(self.sess.opts.share_generics());
self.sess.crate_types().iter().any(|crate_type| {
match crate_type {
CrateType::Executable
| CrateType::Staticlib
| CrateType::ProcMacro
| CrateType::Cdylib => false,
// FIXME rust-lang/rust#64319, rust-lang/rust#64872:
// We want to block export of generics from dylibs,
// but we must fix rust-lang/rust#65890 before we can
// do that robustly.
CrateType::Dylib => true,
CrateType::Rlib => true,
}
})
}
/// Returns the `DefId` and the `BoundRegionKind` corresponding to the given region.
pub fn is_suitable_region(self, region: Region<'tcx>) -> Option<FreeRegionInfo> {
let (suitable_region_binding_scope, bound_region) = match *region {
ty::ReFree(ref free_region) => {
(free_region.scope.expect_local(), free_region.bound_region)
}
ty::ReEarlyBound(ref ebr) => (
self.local_parent(ebr.def_id.expect_local()),
ty::BoundRegionKind::BrNamed(ebr.def_id, ebr.name),
),
_ => return None, // not a free region
};
let is_impl_item = match self.hir().find_by_def_id(suitable_region_binding_scope) {
Some(Node::Item(..) | Node::TraitItem(..)) => false,
Some(Node::ImplItem(..)) => {
self.is_bound_region_in_impl_item(suitable_region_binding_scope)
}
_ => return None,
};
Some(FreeRegionInfo {
def_id: suitable_region_binding_scope,
boundregion: bound_region,
is_impl_item,
})
}
/// Given a `DefId` for an `fn`, return all the `dyn` and `impl` traits in its return type.
pub fn return_type_impl_or_dyn_traits(
self,
scope_def_id: LocalDefId,
) -> Vec<&'tcx hir::Ty<'tcx>> {
let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id) else {
return vec![];
};
let mut v = TraitObjectVisitor(vec![], self.hir());
v.visit_ty(hir_output);
v.0
}
/// Given a `DefId` for an `fn`, return all the `dyn` and `impl` traits in
/// its return type, and the associated alias span when type alias is used,
/// along with a span for lifetime suggestion (if there are existing generics).
pub fn return_type_impl_or_dyn_traits_with_type_alias(
self,
scope_def_id: LocalDefId,
) -> Option<(Vec<&'tcx hir::Ty<'tcx>>, Span, Option<Span>)> {
let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
let mut v = TraitObjectVisitor(vec![], self.hir());
// when the return type is a type alias
if let Some(hir::FnDecl { output: hir::FnRetTy::Return(hir_output), .. }) = self.hir().fn_decl_by_hir_id(hir_id)
&& let hir::TyKind::Path(hir::QPath::Resolved(
None,
hir::Path { res: hir::def::Res::Def(DefKind::TyAlias, def_id), .. }, )) = hir_output.kind
&& let Some(local_id) = def_id.as_local()
&& let Some(alias_ty) = self.hir().get_by_def_id(local_id).alias_ty() // it is type alias
&& let Some(alias_generics) = self.hir().get_by_def_id(local_id).generics()
{
v.visit_ty(alias_ty);
if !v.0.is_empty() {
return Some((v.0, alias_generics.span, alias_generics.span_for_lifetime_suggestion()));
}
}
return None;
}
pub fn return_type_impl_trait(self, scope_def_id: LocalDefId) -> Option<(Ty<'tcx>, Span)> {
// `type_of()` will fail on these (#55796, #86483), so only allow `fn`s or closures.
match self.hir().get_by_def_id(scope_def_id) {
Node::Item(&hir::Item { kind: ItemKind::Fn(..), .. }) => {}
Node::TraitItem(&hir::TraitItem { kind: TraitItemKind::Fn(..), .. }) => {}
Node::ImplItem(&hir::ImplItem { kind: ImplItemKind::Fn(..), .. }) => {}
Node::Expr(&hir::Expr { kind: ExprKind::Closure { .. }, .. }) => {}
_ => return None,
}
let ret_ty = self.type_of(scope_def_id).subst_identity();
match ret_ty.kind() {
ty::FnDef(_, _) => {
let sig = ret_ty.fn_sig(self);
let output = self.erase_late_bound_regions(sig.output());
output.is_impl_trait().then(|| {
let hir_id = self.hir().local_def_id_to_hir_id(scope_def_id);
let fn_decl = self.hir().fn_decl_by_hir_id(hir_id).unwrap();
(output, fn_decl.output.span())
})
}
_ => None,
}
}
/// Checks if the bound region is in Impl Item.
pub fn is_bound_region_in_impl_item(self, suitable_region_binding_scope: LocalDefId) -> bool {
let container_id = self.parent(suitable_region_binding_scope.to_def_id());
if self.impl_trait_ref(container_id).is_some() {
// For now, we do not try to target impls of traits. This is
// because this message is going to suggest that the user
// change the fn signature, but they may not be free to do so,
// since the signature must match the trait.
//
// FIXME(#42706) -- in some cases, we could do better here.
return true;
}
false
}
/// Determines whether identifiers in the assembly have strict naming rules.
/// Currently, only NVPTX* targets need it.
pub fn has_strict_asm_symbol_naming(self) -> bool {
self.sess.target.arch.contains("nvptx")
}
/// Returns `&'static core::panic::Location<'static>`.
pub fn caller_location_ty(self) -> Ty<'tcx> {
self.mk_imm_ref(
self.lifetimes.re_static,
self.type_of(self.require_lang_item(LangItem::PanicLocation, None))
.subst(self, self.mk_substs(&[self.lifetimes.re_static.into()])),
)
}
/// Returns a displayable description and article for the given `def_id` (e.g. `("a", "struct")`).
pub fn article_and_description(self, def_id: DefId) -> (&'static str, &'static str) {
let kind = self.def_kind(def_id);
(self.def_kind_descr_article(kind, def_id), self.def_kind_descr(kind, def_id))
}
pub fn type_length_limit(self) -> Limit {
self.limits(()).type_length_limit
}
pub fn recursion_limit(self) -> Limit {
self.limits(()).recursion_limit
}
pub fn move_size_limit(self) -> Limit {
self.limits(()).move_size_limit
}
pub fn const_eval_limit(self) -> Limit {
if self.sess.opts.unstable_opts.tiny_const_eval_limit {
TINY_CONST_EVAL_LIMIT
} else {
self.limits(()).const_eval_limit
}
}
pub fn all_traits(self) -> impl Iterator<Item = DefId> + 'tcx {
iter::once(LOCAL_CRATE)
.chain(self.crates(()).iter().copied())
.flat_map(move |cnum| self.traits_in_crate(cnum).iter().copied())
}
#[inline]
pub fn local_visibility(self, def_id: LocalDefId) -> Visibility {
self.visibility(def_id).expect_local()
}
}
/// A trait implemented for all `X<'a>` types that can be safely and
/// efficiently converted to `X<'tcx>` as long as they are part of the
/// provided `TyCtxt<'tcx>`.
/// This can be done, for example, for `Ty<'tcx>` or `SubstsRef<'tcx>`
/// by looking them up in their respective interners.
///
/// However, this is still not the best implementation as it does
/// need to compare the components, even for interned values.
/// It would be more efficient if `TypedArena` provided a way to
/// determine whether the address is in the allocated range.
///
/// `None` is returned if the value or one of the components is not part
/// of the provided context.
/// For `Ty`, `None` can be returned if either the type interner doesn't
/// contain the `TyKind` key or if the address of the interned
/// pointer differs. The latter case is possible if a primitive type,
/// e.g., `()` or `u8`, was interned in a different context.
pub trait Lift<'tcx>: fmt::Debug {
type Lifted: fmt::Debug + 'tcx;
fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted>;
}
macro_rules! nop_lift {
($set:ident; $ty:ty => $lifted:ty) => {
impl<'a, 'tcx> Lift<'tcx> for $ty {
type Lifted = $lifted;
fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
tcx.interners
.$set
.contains_pointer_to(&InternedInSet(&*self.0.0))
// SAFETY: `self` is interned and therefore valid
// for the entire lifetime of the `TyCtxt`.
.then(|| unsafe { mem::transmute(self) })
}
}
};
}
macro_rules! nop_list_lift {
($set:ident; $ty:ty => $lifted:ty) => {
impl<'a, 'tcx> Lift<'tcx> for &'a List<$ty> {
type Lifted = &'tcx List<$lifted>;
fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
if self.is_empty() {
return Some(List::empty());
}
tcx.interners
.$set
.contains_pointer_to(&InternedInSet(self))
.then(|| unsafe { mem::transmute(self) })
}
}
};
}
nop_lift! {type_; Ty<'a> => Ty<'tcx>}
nop_lift! {region; Region<'a> => Region<'tcx>}
nop_lift! {const_; Const<'a> => Const<'tcx>}
nop_lift! {const_allocation; ConstAllocation<'a> => ConstAllocation<'tcx>}
nop_lift! {predicate; Predicate<'a> => Predicate<'tcx>}
nop_list_lift! {type_lists; Ty<'a> => Ty<'tcx>}
nop_list_lift! {poly_existential_predicates; PolyExistentialPredicate<'a> => PolyExistentialPredicate<'tcx>}
nop_list_lift! {predicates; Predicate<'a> => Predicate<'tcx>}
nop_list_lift! {canonical_var_infos; CanonicalVarInfo<'a> => CanonicalVarInfo<'tcx>}
nop_list_lift! {projs; ProjectionKind => ProjectionKind}
nop_list_lift! {bound_variable_kinds; ty::BoundVariableKind => ty::BoundVariableKind}
// This is the impl for `&'a InternalSubsts<'a>`.
nop_list_lift! {substs; GenericArg<'a> => GenericArg<'tcx>}
CloneLiftImpls! {
Constness,
traits::WellFormedLoc,
ImplPolarity,
crate::mir::ReturnConstraint,
}
macro_rules! sty_debug_print {
($fmt: expr, $ctxt: expr, $($variant: ident),*) => {{
// Curious inner module to allow variant names to be used as
// variable names.
#[allow(non_snake_case)]
mod inner {
use crate::ty::{self, TyCtxt};
use crate::ty::context::InternedInSet;
#[derive(Copy, Clone)]
struct DebugStat {
total: usize,
lt_infer: usize,
ty_infer: usize,
ct_infer: usize,
all_infer: usize,
}
pub fn go(fmt: &mut std::fmt::Formatter<'_>, tcx: TyCtxt<'_>) -> std::fmt::Result {
let mut total = DebugStat {
total: 0,
lt_infer: 0,
ty_infer: 0,
ct_infer: 0,
all_infer: 0,
};
$(let mut $variant = total;)*
let shards = tcx.interners.type_.lock_shards();
let types = shards.iter().flat_map(|shard| shard.keys());
for &InternedInSet(t) in types {
let variant = match t.internee {
ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
ty::Float(..) | ty::Str | ty::Never => continue,
ty::Error(_) => /* unimportant */ continue,
$(ty::$variant(..) => &mut $variant,)*
};
let lt = t.flags.intersects(ty::TypeFlags::HAS_RE_INFER);
let ty = t.flags.intersects(ty::TypeFlags::HAS_TY_INFER);
let ct = t.flags.intersects(ty::TypeFlags::HAS_CT_INFER);
variant.total += 1;
total.total += 1;
if lt { total.lt_infer += 1; variant.lt_infer += 1 }
if ty { total.ty_infer += 1; variant.ty_infer += 1 }
if ct { total.ct_infer += 1; variant.ct_infer += 1 }
if lt && ty && ct { total.all_infer += 1; variant.all_infer += 1 }
}
writeln!(fmt, "Ty interner total ty lt ct all")?;
$(writeln!(fmt, " {:18}: {uses:6} {usespc:4.1}%, \
{ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
stringify!($variant),
uses = $variant.total,
usespc = $variant.total as f64 * 100.0 / total.total as f64,
ty = $variant.ty_infer as f64 * 100.0 / total.total as f64,
lt = $variant.lt_infer as f64 * 100.0 / total.total as f64,
ct = $variant.ct_infer as f64 * 100.0 / total.total as f64,
all = $variant.all_infer as f64 * 100.0 / total.total as f64)?;
)*
writeln!(fmt, " total {uses:6} \
{ty:4.1}% {lt:5.1}% {ct:4.1}% {all:4.1}%",
uses = total.total,
ty = total.ty_infer as f64 * 100.0 / total.total as f64,
lt = total.lt_infer as f64 * 100.0 / total.total as f64,
ct = total.ct_infer as f64 * 100.0 / total.total as f64,
all = total.all_infer as f64 * 100.0 / total.total as f64)
}
}
inner::go($fmt, $ctxt)
}}
}
impl<'tcx> TyCtxt<'tcx> {
pub fn debug_stats(self) -> impl std::fmt::Debug + 'tcx {
struct DebugStats<'tcx>(TyCtxt<'tcx>);
impl<'tcx> std::fmt::Debug for DebugStats<'tcx> {
fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
sty_debug_print!(
fmt,
self.0,
Adt,
Array,
Slice,
RawPtr,
Ref,
FnDef,
FnPtr,
Placeholder,
Generator,
GeneratorWitness,
GeneratorWitnessMIR,
Dynamic,
Closure,
Tuple,
Bound,
Param,
Infer,
Alias,
Foreign
)?;
writeln!(fmt, "InternalSubsts interner: #{}", self.0.interners.substs.len())?;
writeln!(fmt, "Region interner: #{}", self.0.interners.region.len())?;
writeln!(
fmt,
"Const Allocation interner: #{}",
self.0.interners.const_allocation.len()
)?;
writeln!(fmt, "Layout interner: #{}", self.0.interners.layout.len())?;
Ok(())
}
}
DebugStats(self)
}
}
// This type holds a `T` in the interner. The `T` is stored in the arena and
// this type just holds a pointer to it, but it still effectively owns it. It
// impls `Borrow` so that it can be looked up using the original
// (non-arena-memory-owning) types.
struct InternedInSet<'tcx, T: ?Sized>(&'tcx T);
impl<'tcx, T: 'tcx + ?Sized> Clone for InternedInSet<'tcx, T> {
fn clone(&self) -> Self {
InternedInSet(self.0)
}
}
impl<'tcx, T: 'tcx + ?Sized> Copy for InternedInSet<'tcx, T> {}
impl<'tcx, T: 'tcx + ?Sized> IntoPointer for InternedInSet<'tcx, T> {
fn into_pointer(&self) -> *const () {
self.0 as *const _ as *const ()
}
}
#[allow(rustc::usage_of_ty_tykind)]
impl<'tcx, T> Borrow<T> for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
fn borrow(&self) -> &T {
&self.0.internee
}
}
impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
fn eq(&self, other: &InternedInSet<'tcx, WithCachedTypeInfo<T>>) -> bool {
// The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
// `x == y`.
self.0.internee == other.0.internee
}
}
impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, WithCachedTypeInfo<T>> {}
impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
fn hash<H: Hasher>(&self, s: &mut H) {
// The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
self.0.internee.hash(s)
}
}
impl<'tcx, T> Borrow<[T]> for InternedInSet<'tcx, List<T>> {
fn borrow(&self) -> &[T] {
&self.0[..]
}
}
impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, List<T>> {
fn eq(&self, other: &InternedInSet<'tcx, List<T>>) -> bool {
// The `Borrow` trait requires that `x.borrow() == y.borrow()` equals
// `x == y`.
self.0[..] == other.0[..]
}
}
impl<'tcx, T: Eq> Eq for InternedInSet<'tcx, List<T>> {}
impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, List<T>> {
fn hash<H: Hasher>(&self, s: &mut H) {
// The `Borrow` trait requires that `x.borrow().hash(s) == x.hash(s)`.
self.0[..].hash(s)
}
}
macro_rules! direct_interners {
($($name:ident: $vis:vis $method:ident($ty:ty): $ret_ctor:ident -> $ret_ty:ty,)+) => {
$(impl<'tcx> Borrow<$ty> for InternedInSet<'tcx, $ty> {
fn borrow<'a>(&'a self) -> &'a $ty {
&self.0
}
}
impl<'tcx> PartialEq for InternedInSet<'tcx, $ty> {
fn eq(&self, other: &Self) -> bool {
// The `Borrow` trait requires that `x.borrow() == y.borrow()`
// equals `x == y`.
self.0 == other.0
}
}
impl<'tcx> Eq for InternedInSet<'tcx, $ty> {}
impl<'tcx> Hash for InternedInSet<'tcx, $ty> {
fn hash<H: Hasher>(&self, s: &mut H) {
// The `Borrow` trait requires that `x.borrow().hash(s) ==
// x.hash(s)`.
self.0.hash(s)
}
}
impl<'tcx> TyCtxt<'tcx> {
$vis fn $method(self, v: $ty) -> $ret_ty {
$ret_ctor(Interned::new_unchecked(self.interners.$name.intern(v, |v| {
InternedInSet(self.interners.arena.alloc(v))
}).0))
}
})+
}
}
// Functions with a `mk_` prefix are intended for use outside this file and
// crate. Functions with an `intern_` prefix are intended for use within this
// file only, and have a corresponding `mk_` function.
direct_interners! {
region: intern_region(RegionKind<'tcx>): Region -> Region<'tcx>,
const_: intern_const(ConstData<'tcx>): Const -> Const<'tcx>,
const_allocation: pub mk_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
layout: pub mk_layout(LayoutS): Layout -> Layout<'tcx>,
adt_def: pub mk_adt_def_from_data(AdtDefData): AdtDef -> AdtDef<'tcx>,
external_constraints: pub mk_external_constraints(ExternalConstraintsData<'tcx>):
ExternalConstraints -> ExternalConstraints<'tcx>,
}
macro_rules! slice_interners {
($($field:ident: $vis:vis $method:ident($ty:ty)),+ $(,)?) => (
impl<'tcx> TyCtxt<'tcx> {
$($vis fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
if v.is_empty() {
List::empty()
} else {
self.interners.$field.intern_ref(v, || {
InternedInSet(List::from_arena(&*self.arena, v))
}).0
}
})+
}
);
}
// These functions intern slices. They all have a corresponding
// `mk_foo_from_iter` function that interns an iterator. The slice version
// should be used when possible, because it's faster.
slice_interners!(
const_lists: pub mk_const_list(Const<'tcx>),
substs: pub mk_substs(GenericArg<'tcx>),
type_lists: pub mk_type_list(Ty<'tcx>),
canonical_var_infos: pub mk_canonical_var_infos(CanonicalVarInfo<'tcx>),
poly_existential_predicates: intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
predicates: intern_predicates(Predicate<'tcx>),
projs: pub mk_projs(ProjectionKind),
place_elems: pub mk_place_elems(PlaceElem<'tcx>),
bound_variable_kinds: pub mk_bound_variable_kinds(ty::BoundVariableKind),
fields: pub mk_fields(FieldIdx),
);
impl<'tcx> TyCtxt<'tcx> {
/// Given a `fn` type, returns an equivalent `unsafe fn` type;
/// that is, a `fn` type that is equivalent in every way for being
/// unsafe.
pub fn safe_to_unsafe_fn_ty(self, sig: PolyFnSig<'tcx>) -> Ty<'tcx> {
assert_eq!(sig.unsafety(), hir::Unsafety::Normal);
self.mk_fn_ptr(sig.map_bound(|sig| ty::FnSig { unsafety: hir::Unsafety::Unsafe, ..sig }))
}
/// Given the def_id of a Trait `trait_def_id` and the name of an associated item `assoc_name`
/// returns true if the `trait_def_id` defines an associated item of name `assoc_name`.
pub fn trait_may_define_assoc_item(self, trait_def_id: DefId, assoc_name: Ident) -> bool {
self.super_traits_of(trait_def_id).any(|trait_did| {
self.associated_items(trait_did)
.filter_by_name_unhygienic(assoc_name.name)
.any(|item| self.hygienic_eq(assoc_name, item.ident(self), trait_did))
})
}
/// Given a `ty`, return whether it's an `impl Future<...>`.
pub fn ty_is_opaque_future(self, ty: Ty<'_>) -> bool {
let ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }) = ty.kind() else { return false };
let future_trait = self.require_lang_item(LangItem::Future, None);
self.explicit_item_bounds(def_id).skip_binder().iter().any(|&(predicate, _)| {
let ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) = predicate.kind().skip_binder() else {
return false;
};
trait_predicate.trait_ref.def_id == future_trait
&& trait_predicate.polarity == ImplPolarity::Positive
})
}
/// Computes the def-ids of the transitive supertraits of `trait_def_id`. This (intentionally)
/// does not compute the full elaborated super-predicates but just the set of def-ids. It is used
/// to identify which traits may define a given associated type to help avoid cycle errors.
/// Returns a `DefId` iterator.
fn super_traits_of(self, trait_def_id: DefId) -> impl Iterator<Item = DefId> + 'tcx {
let mut set = FxHashSet::default();
let mut stack = vec![trait_def_id];
set.insert(trait_def_id);
iter::from_fn(move || -> Option<DefId> {
let trait_did = stack.pop()?;
let generic_predicates = self.super_predicates_of(trait_did);
for (predicate, _) in generic_predicates.predicates {
if let ty::PredicateKind::Clause(ty::Clause::Trait(data)) =
predicate.kind().skip_binder()
{
if set.insert(data.def_id()) {
stack.push(data.def_id());
}
}
}
Some(trait_did)
})
}
/// Given a closure signature, returns an equivalent fn signature. Detuples
/// and so forth -- so e.g., if we have a sig with `Fn<(u32, i32)>` then
/// you would get a `fn(u32, i32)`.
/// `unsafety` determines the unsafety of the fn signature. If you pass
/// `hir::Unsafety::Unsafe` in the previous example, then you would get
/// an `unsafe fn (u32, i32)`.
/// It cannot convert a closure that requires unsafe.
pub fn signature_unclosure(
self,
sig: PolyFnSig<'tcx>,
unsafety: hir::Unsafety,
) -> PolyFnSig<'tcx> {
sig.map_bound(|s| {
let params = match s.inputs()[0].kind() {
ty::Tuple(params) => *params,
_ => bug!(),
};
self.mk_fn_sig(params, s.output(), s.c_variadic, unsafety, abi::Abi::Rust)
})
}
// Avoid this in favour of more specific `mk_*` methods, where possible.
#[allow(rustc::usage_of_ty_tykind)]
#[inline]
pub fn mk_ty_from_kind(self, st: TyKind<'tcx>) -> Ty<'tcx> {
self.interners.intern_ty(
st,
self.sess,
// This is only used to create a stable hashing context.
&self.untracked,
)
}
#[inline]
pub fn mk_predicate(self, binder: Binder<'tcx, PredicateKind<'tcx>>) -> Predicate<'tcx> {
self.interners.intern_predicate(
binder,
self.sess,
// This is only used to create a stable hashing context.
&self.untracked,
)
}
#[inline]
pub fn reuse_or_mk_predicate(
self,
pred: Predicate<'tcx>,
binder: Binder<'tcx, PredicateKind<'tcx>>,
) -> Predicate<'tcx> {
if pred.kind() != binder { self.mk_predicate(binder) } else { pred }
}
pub fn mk_mach_int(self, tm: IntTy) -> Ty<'tcx> {
match tm {
IntTy::Isize => self.types.isize,
IntTy::I8 => self.types.i8,
IntTy::I16 => self.types.i16,
IntTy::I32 => self.types.i32,
IntTy::I64 => self.types.i64,
IntTy::I128 => self.types.i128,
}
}
pub fn mk_mach_uint(self, tm: UintTy) -> Ty<'tcx> {
match tm {
UintTy::Usize => self.types.usize,
UintTy::U8 => self.types.u8,
UintTy::U16 => self.types.u16,
UintTy::U32 => self.types.u32,
UintTy::U64 => self.types.u64,
UintTy::U128 => self.types.u128,
}
}
pub fn mk_mach_float(self, tm: FloatTy) -> Ty<'tcx> {
match tm {
FloatTy::F32 => self.types.f32,
FloatTy::F64 => self.types.f64,
}
}
#[inline]
pub fn mk_static_str(self) -> Ty<'tcx> {
self.mk_imm_ref(self.lifetimes.re_static, self.types.str_)
}
#[inline]
pub fn mk_adt(self, def: AdtDef<'tcx>, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
// Take a copy of substs so that we own the vectors inside.
self.mk_ty_from_kind(Adt(def, substs))
}
#[inline]
pub fn mk_foreign(self, def_id: DefId) -> Ty<'tcx> {
self.mk_ty_from_kind(Foreign(def_id))
}
fn mk_generic_adt(self, wrapper_def_id: DefId, ty_param: Ty<'tcx>) -> Ty<'tcx> {
let adt_def = self.adt_def(wrapper_def_id);
let substs =
InternalSubsts::for_item(self, wrapper_def_id, |param, substs| match param.kind {
GenericParamDefKind::Lifetime | GenericParamDefKind::Const { .. } => bug!(),
GenericParamDefKind::Type { has_default, .. } => {
if param.index == 0 {
ty_param.into()
} else {
assert!(has_default);
self.type_of(param.def_id).subst(self, substs).into()
}
}
});
self.mk_ty_from_kind(Adt(adt_def, substs))
}
#[inline]
pub fn mk_box(self, ty: Ty<'tcx>) -> Ty<'tcx> {
let def_id = self.require_lang_item(LangItem::OwnedBox, None);
self.mk_generic_adt(def_id, ty)
}
#[inline]
pub fn mk_lang_item(self, ty: Ty<'tcx>, item: LangItem) -> Option<Ty<'tcx>> {
let def_id = self.lang_items().get(item)?;
Some(self.mk_generic_adt(def_id, ty))
}
#[inline]
pub fn mk_diagnostic_item(self, ty: Ty<'tcx>, name: Symbol) -> Option<Ty<'tcx>> {
let def_id = self.get_diagnostic_item(name)?;
Some(self.mk_generic_adt(def_id, ty))
}
#[inline]
pub fn mk_maybe_uninit(self, ty: Ty<'tcx>) -> Ty<'tcx> {
let def_id = self.require_lang_item(LangItem::MaybeUninit, None);
self.mk_generic_adt(def_id, ty)
}
#[inline]
pub fn mk_ptr(self, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(RawPtr(tm))
}
#[inline]
pub fn mk_ref(self, r: Region<'tcx>, tm: TypeAndMut<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(Ref(r, tm.ty, tm.mutbl))
}
#[inline]
pub fn mk_mut_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Mut })
}
#[inline]
pub fn mk_imm_ref(self, r: Region<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
self.mk_ref(r, TypeAndMut { ty, mutbl: hir::Mutability::Not })
}
#[inline]
pub fn mk_mut_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Mut })
}
#[inline]
pub fn mk_imm_ptr(self, ty: Ty<'tcx>) -> Ty<'tcx> {
self.mk_ptr(TypeAndMut { ty, mutbl: hir::Mutability::Not })
}
#[inline]
pub fn mk_array(self, ty: Ty<'tcx>, n: u64) -> Ty<'tcx> {
self.mk_ty_from_kind(Array(ty, ty::Const::from_target_usize(self, n)))
}
#[inline]
pub fn mk_array_with_const_len(self, ty: Ty<'tcx>, ct: Const<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(Array(ty, ct))
}
#[inline]
pub fn mk_slice(self, ty: Ty<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(Slice(ty))
}
#[inline]
pub fn mk_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
if ts.is_empty() {
self.types.unit
} else {
self.mk_ty_from_kind(Tuple(self.mk_type_list(&ts)))
}
}
pub fn mk_tup_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, Ty<'tcx>>,
{
T::collect_and_apply(iter, |ts| self.mk_tup(ts))
}
#[inline]
pub fn mk_unit(self) -> Ty<'tcx> {
self.types.unit
}
#[inline]
pub fn mk_diverging_default(self) -> Ty<'tcx> {
if self.features().never_type_fallback { self.types.never } else { self.types.unit }
}
#[inline]
pub fn mk_fn_def(
self,
def_id: DefId,
substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> Ty<'tcx> {
let substs = self.check_and_mk_substs(def_id, substs);
self.mk_ty_from_kind(FnDef(def_id, substs))
}
#[inline(always)]
pub(crate) fn check_and_mk_substs(
self,
_def_id: DefId,
substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> SubstsRef<'tcx> {
let substs = substs.into_iter().map(Into::into);
#[cfg(debug_assertions)]
{
let generics = self.generics_of(_def_id);
let n = if let DefKind::AssocTy = self.def_kind(_def_id)
&& let DefKind::Impl { of_trait: false } = self.def_kind(self.parent(_def_id))
{
// If this is an inherent projection.
generics.params.len() + 1
} else {
generics.count()
};
assert_eq!(
(n, Some(n)),
substs.size_hint(),
"wrong number of generic parameters for {_def_id:?}: {:?}",
substs.collect::<Vec<_>>(),
);
}
self.mk_substs_from_iter(substs)
}
#[inline]
pub fn mk_fn_ptr(self, fty: PolyFnSig<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(FnPtr(fty))
}
#[inline]
pub fn mk_dynamic(
self,
obj: &'tcx List<PolyExistentialPredicate<'tcx>>,
reg: ty::Region<'tcx>,
repr: DynKind,
) -> Ty<'tcx> {
self.mk_ty_from_kind(Dynamic(obj, reg, repr))
}
#[inline]
pub fn mk_projection(
self,
item_def_id: DefId,
substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> Ty<'tcx> {
self.mk_alias(ty::Projection, self.mk_alias_ty(item_def_id, substs))
}
#[inline]
pub fn mk_closure(self, closure_id: DefId, closure_substs: SubstsRef<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(Closure(closure_id, closure_substs))
}
#[inline]
pub fn mk_generator(
self,
id: DefId,
generator_substs: SubstsRef<'tcx>,
movability: hir::Movability,
) -> Ty<'tcx> {
self.mk_ty_from_kind(Generator(id, generator_substs, movability))
}
#[inline]
pub fn mk_generator_witness(self, types: ty::Binder<'tcx, &'tcx List<Ty<'tcx>>>) -> Ty<'tcx> {
self.mk_ty_from_kind(GeneratorWitness(types))
}
/// Creates a `&mut Context<'_>` [`Ty`] with erased lifetimes.
pub fn mk_task_context(self) -> Ty<'tcx> {
let context_did = self.require_lang_item(LangItem::Context, None);
let context_adt_ref = self.adt_def(context_did);
let context_substs = self.mk_substs(&[self.lifetimes.re_erased.into()]);
let context_ty = self.mk_adt(context_adt_ref, context_substs);
self.mk_mut_ref(self.lifetimes.re_erased, context_ty)
}
#[inline]
pub fn mk_generator_witness_mir(self, id: DefId, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
self.mk_ty_from_kind(GeneratorWitnessMIR(id, substs))
}
#[inline]
pub fn mk_const(self, kind: impl Into<ty::ConstKind<'tcx>>, ty: Ty<'tcx>) -> Const<'tcx> {
self.intern_const(ty::ConstData { kind: kind.into(), ty })
}
#[inline]
pub fn mk_ty_var(self, v: TyVid) -> Ty<'tcx> {
// Use a pre-interned one when possible.
self.types
.ty_vars
.get(v.as_usize())
.copied()
.unwrap_or_else(|| self.mk_ty_from_kind(Infer(TyVar(v))))
}
#[inline]
pub fn mk_int_var(self, v: IntVid) -> Ty<'tcx> {
self.mk_ty_from_kind(Infer(IntVar(v)))
}
#[inline]
pub fn mk_float_var(self, v: FloatVid) -> Ty<'tcx> {
self.mk_ty_from_kind(Infer(FloatVar(v)))
}
#[inline]
pub fn mk_fresh_ty(self, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
self.types
.fresh_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| self.mk_ty_from_kind(Infer(ty::FreshTy(n))))
}
#[inline]
pub fn mk_fresh_int_ty(self, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
self.types
.fresh_int_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| self.mk_ty_from_kind(Infer(ty::FreshIntTy(n))))
}
#[inline]
pub fn mk_fresh_float_ty(self, n: u32) -> Ty<'tcx> {
// Use a pre-interned one when possible.
self.types
.fresh_float_tys
.get(n as usize)
.copied()
.unwrap_or_else(|| self.mk_ty_from_kind(Infer(ty::FreshFloatTy(n))))
}
#[inline]
pub fn mk_ty_param(self, index: u32, name: Symbol) -> Ty<'tcx> {
self.mk_ty_from_kind(Param(ParamTy { index, name }))
}
pub fn mk_param_from_def(self, param: &ty::GenericParamDef) -> GenericArg<'tcx> {
match param.kind {
GenericParamDefKind::Lifetime => {
self.mk_re_early_bound(param.to_early_bound_region_data()).into()
}
GenericParamDefKind::Type { .. } => self.mk_ty_param(param.index, param.name).into(),
GenericParamDefKind::Const { .. } => self
.mk_const(
ParamConst { index: param.index, name: param.name },
self.type_of(param.def_id)
.no_bound_vars()
.expect("const parameter types cannot be generic"),
)
.into(),
}
}
#[inline]
pub fn mk_bound(self, index: ty::DebruijnIndex, bound_ty: ty::BoundTy) -> Ty<'tcx> {
self.mk_ty_from_kind(Bound(index, bound_ty))
}
#[inline]
pub fn mk_placeholder(self, placeholder: ty::PlaceholderType) -> Ty<'tcx> {
self.mk_ty_from_kind(Placeholder(placeholder))
}
#[inline]
pub fn mk_alias(self, kind: ty::AliasKind, alias_ty: ty::AliasTy<'tcx>) -> Ty<'tcx> {
debug_assert_matches!(
(kind, self.def_kind(alias_ty.def_id)),
(ty::Opaque, DefKind::OpaqueTy)
| (ty::Projection | ty::Inherent, DefKind::AssocTy)
| (ty::Opaque | ty::Projection, DefKind::ImplTraitPlaceholder)
);
self.mk_ty_from_kind(Alias(kind, alias_ty))
}
#[inline]
pub fn mk_opaque(self, def_id: DefId, substs: SubstsRef<'tcx>) -> Ty<'tcx> {
self.mk_alias(ty::Opaque, self.mk_alias_ty(def_id, substs))
}
#[inline]
pub fn mk_re_early_bound(self, early_bound_region: ty::EarlyBoundRegion) -> Region<'tcx> {
self.intern_region(ty::ReEarlyBound(early_bound_region))
}
#[inline]
pub fn mk_re_late_bound(
self,
debruijn: ty::DebruijnIndex,
bound_region: ty::BoundRegion,
) -> Region<'tcx> {
// Use a pre-interned one when possible.
if let ty::BoundRegion { var, kind: ty::BrAnon(None) } = bound_region
&& let Some(inner) = self.lifetimes.re_late_bounds.get(debruijn.as_usize())
&& let Some(re) = inner.get(var.as_usize()).copied()
{
re
} else {
self.intern_region(ty::ReLateBound(debruijn, bound_region))
}
}
#[inline]
pub fn mk_re_free(self, scope: DefId, bound_region: ty::BoundRegionKind) -> Region<'tcx> {
self.intern_region(ty::ReFree(ty::FreeRegion { scope, bound_region }))
}
#[inline]
pub fn mk_re_var(self, v: ty::RegionVid) -> Region<'tcx> {
// Use a pre-interned one when possible.
self.lifetimes
.re_vars
.get(v.as_usize())
.copied()
.unwrap_or_else(|| self.intern_region(ty::ReVar(v)))
}
#[inline]
pub fn mk_re_placeholder(self, placeholder: ty::PlaceholderRegion) -> Region<'tcx> {
self.intern_region(ty::RePlaceholder(placeholder))
}
// Avoid this in favour of more specific `mk_re_*` methods, where possible,
// to avoid the cost of the `match`.
pub fn mk_region_from_kind(self, kind: ty::RegionKind<'tcx>) -> Region<'tcx> {
match kind {
ty::ReEarlyBound(region) => self.mk_re_early_bound(region),
ty::ReLateBound(debruijn, region) => self.mk_re_late_bound(debruijn, region),
ty::ReFree(ty::FreeRegion { scope, bound_region }) => {
self.mk_re_free(scope, bound_region)
}
ty::ReStatic => self.lifetimes.re_static,
ty::ReVar(vid) => self.mk_re_var(vid),
ty::RePlaceholder(region) => self.mk_re_placeholder(region),
ty::ReErased => self.lifetimes.re_erased,
ty::ReError(reported) => self.mk_re_error(reported),
}
}
pub fn mk_place_field(self, place: Place<'tcx>, f: FieldIdx, ty: Ty<'tcx>) -> Place<'tcx> {
self.mk_place_elem(place, PlaceElem::Field(f, ty))
}
pub fn mk_place_deref(self, place: Place<'tcx>) -> Place<'tcx> {
self.mk_place_elem(place, PlaceElem::Deref)
}
pub fn mk_place_downcast(
self,
place: Place<'tcx>,
adt_def: AdtDef<'tcx>,
variant_index: VariantIdx,
) -> Place<'tcx> {
self.mk_place_elem(
place,
PlaceElem::Downcast(Some(adt_def.variant(variant_index).name), variant_index),
)
}
pub fn mk_place_downcast_unnamed(
self,
place: Place<'tcx>,
variant_index: VariantIdx,
) -> Place<'tcx> {
self.mk_place_elem(place, PlaceElem::Downcast(None, variant_index))
}
pub fn mk_place_index(self, place: Place<'tcx>, index: Local) -> Place<'tcx> {
self.mk_place_elem(place, PlaceElem::Index(index))
}
/// This method copies `Place`'s projection, add an element and reintern it. Should not be used
/// to build a full `Place` it's just a convenient way to grab a projection and modify it in
/// flight.
pub fn mk_place_elem(self, place: Place<'tcx>, elem: PlaceElem<'tcx>) -> Place<'tcx> {
let mut projection = place.projection.to_vec();
projection.push(elem);
Place { local: place.local, projection: self.mk_place_elems(&projection) }
}
pub fn mk_poly_existential_predicates(
self,
eps: &[PolyExistentialPredicate<'tcx>],
) -> &'tcx List<PolyExistentialPredicate<'tcx>> {
assert!(!eps.is_empty());
assert!(
eps.array_windows()
.all(|[a, b]| a.skip_binder().stable_cmp(self, &b.skip_binder())
!= Ordering::Greater)
);
self.intern_poly_existential_predicates(eps)
}
pub fn mk_predicates(self, preds: &[Predicate<'tcx>]) -> &'tcx List<Predicate<'tcx>> {
// FIXME consider asking the input slice to be sorted to avoid
// re-interning permutations, in which case that would be asserted
// here.
self.intern_predicates(preds)
}
pub fn mk_const_list_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<ty::Const<'tcx>, &'tcx List<ty::Const<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_const_list(xs))
}
// Unlike various other `mk_*_from_iter` functions, this one uses `I:
// IntoIterator` instead of `I: Iterator`, and it doesn't have a slice
// variant, because of the need to combine `inputs` and `output`. This
// explains the lack of `_from_iter` suffix.
pub fn mk_fn_sig<I, T>(
self,
inputs: I,
output: I::Item,
c_variadic: bool,
unsafety: hir::Unsafety,
abi: abi::Abi,
) -> T::Output
where
I: IntoIterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, ty::FnSig<'tcx>>,
{
T::collect_and_apply(inputs.into_iter().chain(iter::once(output)), |xs| ty::FnSig {
inputs_and_output: self.mk_type_list(xs),
c_variadic,
unsafety,
abi,
})
}
pub fn mk_poly_existential_predicates_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<
PolyExistentialPredicate<'tcx>,
&'tcx List<PolyExistentialPredicate<'tcx>>,
>,
{
T::collect_and_apply(iter, |xs| self.mk_poly_existential_predicates(xs))
}
pub fn mk_predicates_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<Predicate<'tcx>, &'tcx List<Predicate<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_predicates(xs))
}
pub fn mk_type_list_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, &'tcx List<Ty<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_type_list(xs))
}
pub fn mk_substs_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<GenericArg<'tcx>, &'tcx List<GenericArg<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_substs(xs))
}
pub fn mk_canonical_var_infos_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<CanonicalVarInfo<'tcx>, &'tcx List<CanonicalVarInfo<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_canonical_var_infos(xs))
}
pub fn mk_place_elems_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<PlaceElem<'tcx>, &'tcx List<PlaceElem<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_place_elems(xs))
}
pub fn mk_fields_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<FieldIdx, &'tcx List<FieldIdx>>,
{
T::collect_and_apply(iter, |xs| self.mk_fields(xs))
}
pub fn mk_substs_trait(
self,
self_ty: Ty<'tcx>,
rest: impl IntoIterator<Item = GenericArg<'tcx>>,
) -> SubstsRef<'tcx> {
self.mk_substs_from_iter(iter::once(self_ty.into()).chain(rest))
}
pub fn mk_alias_ty(
self,
def_id: DefId,
substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> ty::AliasTy<'tcx> {
let substs = self.check_and_mk_substs(def_id, substs);
ty::AliasTy { def_id, substs, _use_mk_alias_ty_instead: () }
}
pub fn mk_bound_variable_kinds_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<ty::BoundVariableKind, &'tcx List<ty::BoundVariableKind>>,
{
T::collect_and_apply(iter, |xs| self.mk_bound_variable_kinds(xs))
}
/// Emit a lint at `span` from a lint struct (some type that implements `DecorateLint`,
/// typically generated by `#[derive(LintDiagnostic)]`).
pub fn emit_spanned_lint(
self,
lint: &'static Lint,
hir_id: HirId,
span: impl Into<MultiSpan>,
decorator: impl for<'a> DecorateLint<'a, ()>,
) {
let msg = decorator.msg();
let (level, src) = self.lint_level_at_node(lint, hir_id);
struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, |diag| {
decorator.decorate_lint(diag)
})
}
/// Emit a lint at the appropriate level for a hir node, with an associated span.
///
/// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
///
/// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
#[rustc_lint_diagnostics]
pub fn struct_span_lint_hir(
self,
lint: &'static Lint,
hir_id: HirId,
span: impl Into<MultiSpan>,
msg: impl Into<DiagnosticMessage>,
decorate: impl for<'a, 'b> FnOnce(
&'b mut DiagnosticBuilder<'a, ()>,
) -> &'b mut DiagnosticBuilder<'a, ()>,
) {
let (level, src) = self.lint_level_at_node(lint, hir_id);
struct_lint_level(self.sess, lint, level, src, Some(span.into()), msg, decorate);
}
/// Emit a lint from a lint struct (some type that implements `DecorateLint`, typically
/// generated by `#[derive(LintDiagnostic)]`).
pub fn emit_lint(
self,
lint: &'static Lint,
id: HirId,
decorator: impl for<'a> DecorateLint<'a, ()>,
) {
self.struct_lint_node(lint, id, decorator.msg(), |diag| decorator.decorate_lint(diag))
}
/// Emit a lint at the appropriate level for a hir node.
///
/// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
///
/// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
#[rustc_lint_diagnostics]
pub fn struct_lint_node(
self,
lint: &'static Lint,
id: HirId,
msg: impl Into<DiagnosticMessage>,
decorate: impl for<'a, 'b> FnOnce(
&'b mut DiagnosticBuilder<'a, ()>,
) -> &'b mut DiagnosticBuilder<'a, ()>,
) {
let (level, src) = self.lint_level_at_node(lint, id);
struct_lint_level(self.sess, lint, level, src, None, msg, decorate);
}
pub fn in_scope_traits(self, id: HirId) -> Option<&'tcx [TraitCandidate]> {
let map = self.in_scope_traits_map(id.owner)?;
let candidates = map.get(&id.local_id)?;
Some(candidates)
}
pub fn named_bound_var(self, id: HirId) -> Option<resolve_bound_vars::ResolvedArg> {
debug!(?id, "named_region");
self.named_variable_map(id.owner).and_then(|map| map.get(&id.local_id).cloned())
}
pub fn is_late_bound(self, id: HirId) -> bool {
self.is_late_bound_map(id.owner).map_or(false, |set| set.contains(&id.local_id))
}
pub fn late_bound_vars(self, id: HirId) -> &'tcx List<ty::BoundVariableKind> {
self.mk_bound_variable_kinds(
&self
.late_bound_vars_map(id.owner)
.and_then(|map| map.get(&id.local_id).cloned())
.unwrap_or_else(|| {
bug!("No bound vars found for {}", self.hir().node_to_string(id))
}),
)
}
/// Whether the `def_id` counts as const fn in the current crate, considering all active
/// feature gates
pub fn is_const_fn(self, def_id: DefId) -> bool {
if self.is_const_fn_raw(def_id) {
match self.lookup_const_stability(def_id) {
Some(stability) if stability.is_const_unstable() => {
// has a `rustc_const_unstable` attribute, check whether the user enabled the
// corresponding feature gate.
self.features()
.declared_lib_features
.iter()
.any(|&(sym, _)| sym == stability.feature)
}
// functions without const stability are either stable user written
// const fn or the user is using feature gates and we thus don't
// care what they do
_ => true,
}
} else {
false
}
}
/// Whether the trait impl is marked const. This does not consider stability or feature gates.
pub fn is_const_trait_impl_raw(self, def_id: DefId) -> bool {
let Some(local_def_id) = def_id.as_local() else { return false };
let hir_id = self.local_def_id_to_hir_id(local_def_id);
let node = self.hir().get(hir_id);
matches!(
node,
hir::Node::Item(hir::Item {
kind: hir::ItemKind::Impl(hir::Impl { constness: hir::Constness::Const, .. }),
..
})
)
}
pub fn local_def_id_to_hir_id(self, local_def_id: LocalDefId) -> HirId {
self.opt_local_def_id_to_hir_id(local_def_id).unwrap()
}
pub fn trait_solver_next(self) -> bool {
self.sess.opts.unstable_opts.trait_solver == rustc_session::config::TraitSolver::Next
}
pub fn lower_impl_trait_in_trait_to_assoc_ty(self) -> bool {
self.sess.opts.unstable_opts.lower_impl_trait_in_trait_to_assoc_ty
}
pub fn is_impl_trait_in_trait(self, def_id: DefId) -> bool {
if self.lower_impl_trait_in_trait_to_assoc_ty() {
self.opt_rpitit_info(def_id).is_some()
} else {
self.def_kind(def_id) == DefKind::ImplTraitPlaceholder
}
}
/// Named module children from all kinds of items, including imports.
/// In addition to regular items this list also includes struct and variant constructors, and
/// items inside `extern {}` blocks because all of them introduce names into parent module.
///
/// Module here is understood in name resolution sense - it can be a `mod` item,
/// or a crate root, or an enum, or a trait.
///
/// This is not a query, making it a query causes perf regressions
/// (probably due to hashing spans in `ModChild`ren).
pub fn module_children_local(self, def_id: LocalDefId) -> &'tcx [ModChild] {
self.resolutions(()).module_children.get(&def_id).map_or(&[], |v| &v[..])
}
}
impl<'tcx> TyCtxtAt<'tcx> {
/// Constructs a `TyKind::Error` type and registers a `delay_span_bug` to ensure it gets used.
#[track_caller]
pub fn ty_error_misc(self) -> Ty<'tcx> {
self.tcx.ty_error_with_message(self.span, "TyKind::Error constructed but no error reported")
}
/// Constructs a `TyKind::Error` type and registers a `delay_span_bug` with the given `msg` to
/// ensure it gets used.
#[track_caller]
pub fn ty_error_with_message(self, msg: &str) -> Ty<'tcx> {
self.tcx.ty_error_with_message(self.span, msg)
}
}
/// Parameter attributes that can only be determined by examining the body of a function instead
/// of just its signature.
///
/// These can be useful for optimization purposes when a function is directly called. We compute
/// them and store them into the crate metadata so that downstream crates can make use of them.
///
/// Right now, we only have `read_only`, but `no_capture` and `no_alias` might be useful in the
/// future.
#[derive(Clone, Copy, PartialEq, Debug, Default, TyDecodable, TyEncodable, HashStable)]
pub struct DeducedParamAttrs {
/// The parameter is marked immutable in the function and contains no `UnsafeCell` (i.e. its
/// type is freeze).
pub read_only: bool,
}
pub fn provide(providers: &mut ty::query::Providers) {
providers.maybe_unused_trait_imports =
|tcx, ()| &tcx.resolutions(()).maybe_unused_trait_imports;
providers.names_imported_by_glob_use = |tcx, id| {
tcx.arena.alloc(UnordSet::from(
tcx.resolutions(()).glob_map.get(&id).cloned().unwrap_or_default(),
))
};
providers.extern_mod_stmt_cnum =
|tcx, id| tcx.resolutions(()).extern_crate_map.get(&id).cloned();
providers.is_panic_runtime =
|tcx, LocalCrate| attr::contains_name(tcx.hir().krate_attrs(), sym::panic_runtime);
providers.is_compiler_builtins =
|tcx, LocalCrate| attr::contains_name(tcx.hir().krate_attrs(), sym::compiler_builtins);
providers.has_panic_handler = |tcx, LocalCrate| {
// We want to check if the panic handler was defined in this crate
tcx.lang_items().panic_impl().map_or(false, |did| did.is_local())
};
providers.source_span = |tcx, def_id| tcx.untracked.source_span.get(def_id).unwrap_or(DUMMY_SP);
}