Google Git Google Git
Sign in
rust/rust/af2ca5267d62cc3a9f77458e4fca17d9140c29bb/./compiler/rustc_middle/src/ty/context.rs
blob: 9edb12949f4cf707f399ee2a12f9c906a756da84 [file]
//! Type context book-keeping.
#![allow(rustc::usage_of_ty_tykind)]
mod impl_interner;
pub mod tls;
use std::borrow::{Borrow, Cow};
use std::cmp::Ordering;
use std::env::VarError;
use std::ffi::OsStr;
use std::hash::{Hash, Hasher};
use std::marker::PointeeSized;
use std::ops::Deref;
use std::sync::{Arc, OnceLock};
use std::{debug_assert_matches, fmt, iter, mem};
use rustc_abi::{ExternAbi, FieldIdx, Layout, LayoutData, TargetDataLayout, VariantIdx};
use rustc_ast as ast;
use rustc_attr_ir::find_attr;
use rustc_attr_ir::lang_items::LangItem;
use rustc_crate_store::{CrateStoreDyn, Untracked};
use rustc_data_structures::defer;
use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::intern::Interned;
use rustc_data_structures::profiling::SelfProfilerRef;
use rustc_data_structures::sharded::{IntoPointer, ShardedHashMap};
use rustc_data_structures::stable_hash::StableHash;
use rustc_data_structures::steal::Steal;
use rustc_data_structures::sync::{
self, DynSend, DynSync, FreezeReadGuard, Lock, RwLock, WorkerLocal,
};
use rustc_errors::{Applicability, Diag, DiagCtxtHandle, Diagnostic, MultiSpan};
use rustc_hir::def::DefKind;
use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE, LocalDefId};
use rustc_hir::definitions::{DefPathData, Definitions, PerParentDisambiguatorState};
use rustc_hir::intravisit::Visitor;
use rustc_hir::{self as hir, CRATE_HIR_ID, HirId, Node, TraitCandidate};
use rustc_index::IndexVec;
use rustc_lint_defs::Lint;
use rustc_lint_defs::builtin::UNUSED_FEATURES;
use rustc_macros::Diagnostic;
use rustc_session::{IncrCompSession, Session};
use rustc_span::def_id::{CRATE_DEF_ID, DefPathHash, StableCrateId};
use rustc_span::{DUMMY_SP, Ident, Span, Symbol, bug, kw, sym};
use rustc_structures::{CrateType, Limit};
use rustc_type_ir::TyKind::*;
pub use rustc_type_ir::lift::Lift;
use rustc_type_ir::{CollectAndApply, WithCachedTypeInfo, elaborate, search_graph};
use tracing::{debug, instrument};
use crate::arena::Arena;
use crate::dep_graph::dep_node::make_metadata;
use crate::dep_graph::{DepGraph, DepNodeIndex};
use crate::hir::{ProjectedMaybeOwner, ProjectedOwnerInfo};
use crate::ich::StableHashState;
use crate::infer::canonical::{CanonicalParamEnvCache, CanonicalVarKind};
use crate::lint::emit_lint_base;
use crate::middle::codegen_fn_attrs::{CodegenFnAttrs, TargetFeature};
use crate::middle::resolve::{ModChild, ResolverAstLowering};
use crate::middle::resolve_bound_vars;
use crate::mir::interpret::{self, Allocation, ConstAllocation};
use crate::mir::{Body, Local, Place, PlaceElem, ProjectionKind, Promoted};
use crate::query::{IntoQueryKey, LocalCrate, Providers, QuerySystem, TyCtxtAt};
use crate::thir::Thir;
use crate::traits;
use crate::traits::solve::{
CanonicalInput, CanonicalInputData, ExternalConstraints, ExternalConstraintsData,
PredefinedOpaques,
};
use crate::ty::predicate::ExistentialPredicateStableCmpExt as _;
use crate::ty::{
self, AdtDef, AdtDefData, AdtKind, Binder, Clause, ClausePolarity, Clauses, Const, ConstKind,
FnSigKind, GenericArg, GenericArgs, GenericArgsRef, GenericParamDefKind, List,
ListWithCachedTypeInfo, ParamConst, Pattern, PatternKind, PolyExistentialPredicate, PolyFnSig,
Predicate, PredicateKind, Region, RegionKind, ReprOptions, TraitObjectVisitor, Ty, TyKind,
TyVid, ValTree, ValTreeKind, Visibility,
};
impl<'tcx> rustc_type_ir::inherent::DefId<TyCtxt<'tcx>> for DefId {
fn is_local(self) -> bool {
self.is_local()
}
fn as_local(self) -> Option<LocalDefId> {
self.as_local()
}
}
impl<'tcx> rustc_type_ir::inherent::Safety<TyCtxt<'tcx>> for hir::Safety {
fn safe() -> Self {
hir::Safety::Safe
}
fn unsafe_mode() -> Self {
hir::Safety::Unsafe
}
fn is_safe(self) -> bool {
self.is_safe()
}
fn prefix_str(self) -> &'static str {
self.prefix_str()
}
}
impl<'tcx> rustc_type_ir::inherent::Features<TyCtxt<'tcx>> for &'tcx rustc_feature::Features {
fn generic_const_exprs(self) -> bool {
self.generic_const_exprs()
}
fn generic_const_args(self) -> bool {
self.generic_const_args()
}
fn coroutine_clone(self) -> bool {
self.coroutine_clone()
}
fn feature_bound_holds_in_crate(self, symbol: Symbol) -> bool {
// We don't consider feature bounds to hold in the crate when `staged_api` feature is
// enabled, even if it is enabled through `#[feature]`.
// This is to prevent accidentally leaking unstable APIs to stable.
!self.staged_api() && self.enabled(symbol)
}
}
impl<'tcx> rustc_type_ir::inherent::Span<TyCtxt<'tcx>> for Span {
fn dummy() -> Self {
DUMMY_SP
}
}
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>>>,
args: InternedSet<'tcx, GenericArgs<'tcx>>,
type_lists: InternedSet<'tcx, List<Ty<'tcx>>>,
canonical_var_kinds: InternedSet<'tcx, List<CanonicalVarKind<'tcx>>>,
region: InternedSet<'tcx, RegionKind<'tcx>>,
poly_existential_predicates: InternedSet<'tcx, List<PolyExistentialPredicate<'tcx>>>,
predicate: InternedSet<'tcx, WithCachedTypeInfo<ty::Binder<'tcx, PredicateKind<'tcx>>>>,
clauses: InternedSet<'tcx, ListWithCachedTypeInfo<Clause<'tcx>>>,
projs: InternedSet<'tcx, List<ProjectionKind>>,
place_elems: InternedSet<'tcx, List<PlaceElem<'tcx>>>,
const_: InternedSet<'tcx, WithCachedTypeInfo<ty::ConstKind<'tcx>>>,
pat: InternedSet<'tcx, PatternKind<'tcx>>,
const_allocation: InternedSet<'tcx, Allocation>,
bound_variable_kinds: InternedSet<'tcx, List<ty::BoundVariableKind<'tcx>>>,
layout: InternedSet<'tcx, LayoutData<FieldIdx, VariantIdx>>,
adt_def: InternedSet<'tcx, AdtDefData>,
external_constraints: InternedSet<'tcx, ExternalConstraintsData<TyCtxt<'tcx>>>,
predefined_opaques_in_body: InternedSet<'tcx, List<(ty::OpaqueTypeKey<'tcx>, Ty<'tcx>)>>,
fields: InternedSet<'tcx, List<FieldIdx>>,
local_def_ids: InternedSet<'tcx, List<LocalDefId>>,
captures: InternedSet<'tcx, List<&'tcx ty::CapturedPlace<'tcx>>>,
valtree: InternedSet<'tcx, ty::ValTreeKind<TyCtxt<'tcx>>>,
patterns: InternedSet<'tcx, List<ty::Pattern<'tcx>>>,
outlives: InternedSet<'tcx, List<ty::ArgOutlivesClause<'tcx>>>,
canonical_inputs: InternedSet<'tcx, CanonicalInputData<TyCtxt<'tcx>>>,
}
impl<'tcx> CtxtInterners<'tcx> {
fn new(arena: &'tcx WorkerLocal<Arena<'tcx>>) -> CtxtInterners<'tcx> {
// Default interner size - this value has been chosen empirically, and may need to be
// adjusted as the compiler evolves.
const N: usize = 2048;
CtxtInterners {
arena,
// The factors have been chosen by @FractalFir based on observed interner sizes, and
// local perf runs. To get the interner sizes, insert `eprintln` printing the size of
// the interner in functions like `intern_ty`. Bigger benchmarks tend to give more
// accurate ratios, so use something like `x perf eprintln --includes cargo`.
type_: InternedSet::with_capacity(N * 16),
const_lists: InternedSet::with_capacity(N * 4),
args: InternedSet::with_capacity(N * 4),
type_lists: InternedSet::with_capacity(N * 4),
region: InternedSet::with_capacity(N * 4),
poly_existential_predicates: InternedSet::with_capacity(N / 4),
canonical_var_kinds: InternedSet::with_capacity(N / 2),
predicate: InternedSet::with_capacity(N),
clauses: InternedSet::with_capacity(N),
projs: InternedSet::with_capacity(N * 4),
place_elems: InternedSet::with_capacity(N * 2),
const_: InternedSet::with_capacity(N * 2),
pat: InternedSet::with_capacity(N),
const_allocation: InternedSet::with_capacity(N),
bound_variable_kinds: InternedSet::with_capacity(N * 2),
layout: InternedSet::with_capacity(N),
adt_def: InternedSet::with_capacity(N),
external_constraints: InternedSet::with_capacity(N),
predefined_opaques_in_body: InternedSet::with_capacity(N),
fields: InternedSet::with_capacity(N * 4),
local_def_ids: InternedSet::with_capacity(N),
captures: InternedSet::with_capacity(N),
valtree: InternedSet::with_capacity(N),
patterns: InternedSet::with_capacity(N),
outlives: InternedSet::with_capacity(N),
canonical_inputs: InternedSet::with_capacity(N),
}
}
/// Interns a type. (Use `mk_*` functions instead, where possible.)
#[allow(rustc::usage_of_ty_tykind)]
#[inline(never)]
fn intern_ty(&self, kind: TyKind<'tcx>) -> Ty<'tcx> {
Ty(Interned::new_unchecked(
self.type_
.intern(kind, |kind| {
let flags = ty::FlagComputation::<TyCtxt<'tcx>>::for_kind(&kind);
InternedInSet(self.arena.alloc(WithCachedTypeInfo {
internee: kind,
flags: flags.flags,
outer_exclusive_binder: flags.outer_exclusive_binder,
}))
})
.0,
))
}
/// Interns a const. (Use `mk_*` functions instead, where possible.)
#[allow(rustc::usage_of_ty_tykind)]
#[inline(never)]
fn intern_const(&self, kind: ty::ConstKind<'tcx>) -> Const<'tcx> {
Const(Interned::new_unchecked(
self.const_
.intern(kind, |kind: ty::ConstKind<'_>| {
let flags = ty::FlagComputation::<TyCtxt<'tcx>>::for_const_kind(&kind);
InternedInSet(self.arena.alloc(WithCachedTypeInfo {
internee: kind,
flags: flags.flags,
outer_exclusive_binder: flags.outer_exclusive_binder,
}))
})
.0,
))
}
/// Interns a predicate. (Use `mk_predicate` instead, where possible.)
#[inline(never)]
fn intern_predicate(&self, kind: Binder<'tcx, PredicateKind<'tcx>>) -> Predicate<'tcx> {
Predicate(Interned::new_unchecked(
self.predicate
.intern(kind, |kind| {
let flags = ty::FlagComputation::<TyCtxt<'tcx>>::for_predicate(kind);
InternedInSet(self.arena.alloc(WithCachedTypeInfo {
internee: kind,
flags: flags.flags,
outer_exclusive_binder: flags.outer_exclusive_binder,
}))
})
.0,
))
}
fn intern_clauses(&self, clauses: &[Clause<'tcx>]) -> Clauses<'tcx> {
if clauses.is_empty() {
ListWithCachedTypeInfo::empty()
} else {
self.clauses
.intern_ref(clauses, || {
let flags = ty::FlagComputation::<TyCtxt<'tcx>>::for_clauses(clauses);
InternedInSet(ListWithCachedTypeInfo::from_arena(
&*self.arena,
flags.into(),
clauses,
))
})
.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;
const NUM_PREINTERNED_ANON_BOUND_TYS_I: u32 = 3;
// From general profiling of the *max vars during canonicalization* of a value:
// - about 90% of the time, there are no canonical vars
// - about 9% of the time, there is only one canonical var
// - there are rarely more than 3-5 canonical vars (with exceptions in particularly pathological
// cases)
// This may not match the number of bound vars found in `for`s.
// Given that this is all heap interned, it seems likely that interning fewer
// vars here won't make an appreciable difference. Though, if we were to inline the data (in an
// array), we may want to consider reducing the number for canonicalized vars down to 4 or so.
const NUM_PREINTERNED_ANON_BOUND_TYS_V: u32 = 20;
// 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_ANON_RE_BOUNDS_I: u32 = 3;
const NUM_PREINTERNED_ANON_RE_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 f16: Ty<'tcx>,
pub f32: Ty<'tcx>,
pub f64: Ty<'tcx>,
pub f128: Ty<'tcx>,
pub str_: Ty<'tcx>,
pub never: Ty<'tcx>,
pub self_param: Ty<'tcx>,
/// A dummy type that can be used as the self type of trait object types outside of
/// [`ty::ExistentialTraitRef`], [`ty::ExistentialProjection`], etc.
///
/// This is most useful or even necessary when you want to manipulate existential predicates
/// together with normal predicates or if you want to pass them to an API that only expects
/// normal predicates.
///
/// Indeed, you can sometimes use the trait object type itself as the self type instead of this
/// dummy type. However, that's not always correct: For example, if said trait object type can
/// also appear "naturally" in whatever type system entity you're working with (like predicates)
/// but you still need to be able to identify the erased self type later on.
/// That's when this dummy type comes in handy.
///
/// HIR ty lowering guarantees / has to guarantee that this dummy type doesn't appear in the
/// lowered types, so you can "freely" use it (see warning below).
///
/// <div class="warning">
///
/// Under the hood, this type is just `ty::Infer(ty::FreshTy(0))`. Consequently, you must be
/// sure that fresh types cannot appear by other means in whatever type system entity you're
/// working with.
///
/// Keep uses of this dummy type as local as possible and try not to leak it to subsequent
/// passes!
///
/// </div>
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>>,
/// Pre-interned values of the form:
/// `Bound(BoundVarIndexKind::Bound(DebruijnIndex(i)), BoundTy { var: v, kind:
/// BoundTyKind::Anon})` for small values of `i` and `v`.
pub anon_bound_tys: Vec<Vec<Ty<'tcx>>>,
// Pre-interned values of the form:
// `Bound(BoundVarIndexKind::Canonical, BoundTy { var: v, kind: BoundTyKind::Anon })`
// for small values of `v`.
pub anon_canonical_bound_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:
/// `ReBound(BoundVarIndexKind::Bound(DebruijnIndex(i)), BoundRegion { var: v, kind: BoundRegionKind::Anon })`
/// for small values of `i` and `v`.
pub anon_re_bounds: Vec<Vec<Region<'tcx>>>,
// Pre-interned values of the form:
// `ReBound(BoundVarIndexKind::Canonical, BoundRegion { var: v, kind: BoundRegionKind::Anon })`
// for small values of `v`.
pub anon_re_canonical_bounds: Vec<Region<'tcx>>,
}
pub struct CommonConsts<'tcx> {
pub unit: Const<'tcx>,
pub true_: Const<'tcx>,
pub false_: Const<'tcx>,
/// Use [`ty::ValTree::zst`] instead.
pub(crate) valtree_zst: ValTree<'tcx>,
}
impl<'tcx> CommonTypes<'tcx> {
fn new(interners: &CtxtInterners<'tcx>) -> CommonTypes<'tcx> {
let mk = |ty| interners.intern_ty(ty);
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();
let anon_bound_tys = (0..NUM_PREINTERNED_ANON_BOUND_TYS_I)
.map(|i| {
(0..NUM_PREINTERNED_ANON_BOUND_TYS_V)
.map(|v| {
mk(ty::Bound(
ty::BoundVarIndexKind::Bound(ty::DebruijnIndex::from(i)),
ty::BoundTy { var: ty::BoundVar::from(v), kind: ty::BoundTyKind::Anon },
))
})
.collect()
})
.collect();
let anon_canonical_bound_tys = (0..NUM_PREINTERNED_ANON_BOUND_TYS_V)
.map(|v| {
mk(ty::Bound(
ty::BoundVarIndexKind::Canonical,
ty::BoundTy { var: ty::BoundVar::from(v), kind: ty::BoundTyKind::Anon },
))
})
.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)),
f16: mk(Float(ty::FloatTy::F16)),
f32: mk(Float(ty::FloatTy::F32)),
f64: mk(Float(ty::FloatTy::F64)),
f128: mk(Float(ty::FloatTy::F128)),
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,
anon_bound_tys,
anon_canonical_bound_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 anon_re_bounds = (0..NUM_PREINTERNED_ANON_RE_BOUNDS_I)
.map(|i| {
(0..NUM_PREINTERNED_ANON_RE_BOUNDS_V)
.map(|v| {
mk(ty::ReBound(
ty::BoundVarIndexKind::Bound(ty::DebruijnIndex::from(i)),
ty::BoundRegion {
var: ty::BoundVar::from(v),
kind: ty::BoundRegionKind::Anon,
},
))
})
.collect()
})
.collect();
let anon_re_canonical_bounds = (0..NUM_PREINTERNED_ANON_RE_BOUNDS_V)
.map(|v| {
mk(ty::ReBound(
ty::BoundVarIndexKind::Canonical,
ty::BoundRegion { var: ty::BoundVar::from(v), kind: ty::BoundRegionKind::Anon },
))
})
.collect();
CommonLifetimes {
re_static: mk(ty::ReStatic),
re_erased: mk(ty::ReErased),
re_vars,
anon_re_bounds,
anon_re_canonical_bounds,
}
}
}
impl<'tcx> CommonConsts<'tcx> {
fn new(interners: &CtxtInterners<'tcx>, types: &CommonTypes<'tcx>) -> CommonConsts<'tcx> {
let mk_const = |c| interners.intern_const(c);
let mk_valtree = |v| {
ty::ValTree(Interned::new_unchecked(
interners.valtree.intern(v, |v| InternedInSet(interners.arena.alloc(v))).0,
))
};
let valtree_zst = mk_valtree(ty::ValTreeKind::Branch(List::empty()));
let valtree_true = mk_valtree(ty::ValTreeKind::Leaf(ty::ScalarInt::TRUE));
let valtree_false = mk_valtree(ty::ValTreeKind::Leaf(ty::ScalarInt::FALSE));
CommonConsts {
unit: mk_const(ty::ConstKind::Value(ty::Value {
ty: types.unit,
valtree: valtree_zst,
})),
true_: mk_const(ty::ConstKind::Value(ty::Value {
ty: types.bool,
valtree: valtree_true,
})),
false_: mk_const(ty::ConstKind::Value(ty::Value {
ty: types.bool,
valtree: valtree_false,
})),
valtree_zst,
}
}
}
/// This struct contains information regarding a free parameter region,
/// either a `ReEarlyParam` or `ReLateParam`.
#[derive(Debug)]
pub struct FreeRegionInfo {
/// `LocalDefId` of the scope.
pub scope: LocalDefId,
/// the `DefId` of the free region.
pub region_def_id: DefId,
/// 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, K: Copy> {
pub tcx: TyCtxt<'tcx>,
// Do not allow direct access, as downstream code must not mutate this field.
key: K,
}
/// Only queries that create a `DefId` are allowed to feed queries for that `DefId`.
impl<K: Copy> !StableHash for TyCtxtFeed<'_, K> {}
/// Some workarounds to use cases that cannot use `create_def`.
/// Do not add new ways to create `TyCtxtFeed` without consulting
/// with T-compiler and making an analysis about why your addition
/// does not cause incremental compilation issues.
impl<'tcx> TyCtxt<'tcx> {
/// Can only be fed before queries are run, and is thus exempt from any
/// incremental issues. Do not use except for the initial query feeding.
pub fn feed_unit_query(self) -> TyCtxtFeed<'tcx, ()> {
self.dep_graph.assert_ignored();
TyCtxtFeed { tcx: self, key: () }
}
/// Only used in the resolver to register the `CRATE_DEF_ID` `DefId` and feed
/// some queries for it. It will panic if used twice.
pub fn create_local_crate_def_id(self, span: Span) -> TyCtxtFeed<'tcx, LocalDefId> {
let key = self.untracked().source_span.push(span);
assert_eq!(key, CRATE_DEF_ID);
TyCtxtFeed { tcx: self, key }
}
/// 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<'tcx, Ty<'tcx>>) {
debug_assert_eq!(self.def_kind(key), DefKind::AnonConst);
debug_assert!(self.anon_const_kind(key) != ty::AnonConstKind::NonTypeSystemInline);
TyCtxtFeed { tcx: self, key }.type_of(value)
}
// Trait impl item visibility is inherited from its trait when not specified
// explicitly. In that case we cannot determine it in early resolve,
// but instead are feeding it in late resolve, where we don't have access to the
// `TyCtxtFeed` anymore.
// To avoid having to hash the `LocalDefId` multiple times for inserting and removing the
// `TyCtxtFeed` from a hash table, we add this hack to feed the visibility.
// Do not use outside of the resolver query.
pub fn feed_visibility_for_trait_impl_item(self, key: LocalDefId, vis: ty::Visibility) {
if cfg!(debug_assertions) {
match self.def_kind(self.local_parent(key)) {
DefKind::Impl { of_trait: true } => {}
other => bug!("{key:?} is not an assoc item of a trait impl: {other:?}"),
}
}
TyCtxtFeed { tcx: self, key }.visibility(vis.to_mod_id())
}
}
impl<'tcx, K: Copy> TyCtxtFeed<'tcx, K> {
#[inline(always)]
pub fn key(&self) -> K {
self.key
}
}
impl<'tcx> TyCtxtFeed<'tcx, LocalDefId> {
#[inline(always)]
pub fn def_id(&self) -> LocalDefId {
self.key
}
// Caller must ensure that `self.key` ID is indeed an owner.
pub fn feed_owner_id(&self) -> TyCtxtFeed<'tcx, hir::OwnerId> {
TyCtxtFeed { tcx: self.tcx, key: hir::OwnerId { def_id: self.key } }
}
// Fills in all the important parts needed by HIR queries
pub fn feed_hir(&self) {
self.hir_owner(ProjectedMaybeOwner::Owner(ProjectedOwnerInfo::new(
self.tcx.arena.alloc(hir::OwnerNodes::synthetic()),
self.tcx.arena.alloc(Default::default()),
self.tcx.arena.alloc(Default::default()),
self.tcx.arena.alloc(Steal::new(Default::default())),
)));
self.feed_owner_id().hir_attr_map(hir::AttributeMap::EMPTY);
}
}
/// An assortment of global caches used by various parts of the compiler.
///
/// The individual fields are mostly unrelated to each other, but have been grouped together to
/// reduce the number of top-level fields in [`GlobalCtxt`].
#[derive(Default)]
pub struct GlobalCaches<'tcx> {
// Internal caches for metadata decoding. No need to track deps on this.
pub ty_rcache: Lock<FxHashMap<ty::CReaderCacheKey, Ty<'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, ty::TypingEnv<'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, ty::TypingEnv<'tcx>>,
/// Caches the results of goal evaluation in the new solver.
new_solver_evaluation_cache: Lock<search_graph::GlobalCache<TyCtxt<'tcx>>>,
new_solver_canonical_param_env_cache: Lock<ty::CanonicalParamEnvCache<TyCtxt<'tcx>>>,
pub canonical_param_env_cache: CanonicalParamEnvCache<'tcx>,
/// Caches the index of the highest bound var in clauses in a canonical binder.
pub highest_var_in_clauses_cache: Lock<FxHashMap<ty::Clauses<'tcx>, usize>>,
/// Caches the instantiation of a canonical binder given a set of args.
pub clauses_cache:
Lock<FxHashMap<(ty::Clauses<'tcx>, &'tcx [ty::GenericArg<'tcx>]), ty::Clauses<'tcx>>>,
}
/// 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
///
/// An implementation detail: `TyCtxt` is a wrapper type for [GlobalCtxt],
/// which is the struct that actually holds all the data. `TyCtxt` derefs to
/// `GlobalCtxt`, and in practice `TyCtxt` is passed around everywhere, and all
/// operations are done via `TyCtxt`. A `TyCtxt` is obtained for a `GlobalCtxt`
/// by calling `enter` with a closure `f`. That function creates both the
/// `TyCtxt`, and an `ImplicitCtxt` around it that is put into TLS. Within `f`:
/// - The `ImplicitCtxt` is available implicitly via TLS.
/// - The `TyCtxt` is available explicitly via the `tcx` parameter, and also
/// implicitly within the `ImplicitCtxt`. Explicit access is preferred when
/// possible.
#[derive(Copy, Clone)]
#[rustc_diagnostic_item = "TyCtxt"]
#[rustc_pass_by_value]
pub struct TyCtxt<'tcx> {
gcx: &'tcx GlobalCtxt<'tcx>,
}
// Explicitly implement `DynSync` and `DynSend` for `TyCtxt` to short circuit trait resolution. Its
// field are asserted to implement these traits below, so this is trivially safe, and it greatly
// speeds-up compilation of this crate and its dependents.
unsafe impl DynSend for TyCtxt<'_> {}
unsafe impl DynSync for TyCtxt<'_> {}
fn _assert_tcx_fields() {
sync::assert_dyn_sync::<&'_ GlobalCtxt<'_>>();
sync::assert_dyn_send::<&'_ GlobalCtxt<'_>>();
}
impl<'tcx> Deref for TyCtxt<'tcx> {
type Target = &'tcx GlobalCtxt<'tcx>;
#[inline(always)]
fn deref(&self) -> &Self::Target {
&self.gcx
}
}
/// See [TyCtxt] for details about this type.
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,
crate_types: Vec<CrateType>,
/// The `stable_crate_id` is constructed out of the crate name and all the
/// `-C metadata` arguments passed to the compiler. Its value forms a unique
/// global identifier for the crate. It is used to allow multiple crates
/// with the same name to coexist. See the
/// `rustc_symbol_mangling` crate for more information.
stable_crate_id: StableCrateId,
pub incr_comp_session: Option<&'tcx IncrCompSession>,
pub dep_graph: DepGraph,
/// This duplicates `Session::prof` because this field is hot enough that accessing it via
/// `self.sess.prof` is a measurable slowdown (see #161332).
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>,
/// Hooks to be able to register functions in other crates that can then still
/// be called from rustc_middle.
pub(crate) hooks: crate::hooks::Providers,
untracked: Untracked,
pub query_system: QuerySystem<'tcx>,
pub caches: GlobalCaches<'tcx>,
/// Data layout specification for the current target.
pub data_layout: TargetDataLayout,
/// Stores memory for globals (statics/consts).
pub(crate) alloc_map: interpret::AllocMap<'tcx>,
current_gcx: CurrentGcx,
}
impl<'tcx> GlobalCtxt<'tcx> {
/// Installs `self` in a `TyCtxt` and `ImplicitCtxt` for the duration of
/// `f`.
pub fn enter<F, R>(&'tcx self, f: F) -> R
where
F: FnOnce(TyCtxt<'tcx>) -> R,
{
let icx = tls::ImplicitCtxt::new(self);
// Reset `current_gcx` to `None` when we exit.
let _on_drop = defer(move || {
*self.current_gcx.value.write() = None;
});
// Set this `GlobalCtxt` as the current one.
{
let mut guard = self.current_gcx.value.write();
assert!(guard.is_none(), "no `GlobalCtxt` is currently set");
*guard = Some(self as *const _ as *const ());
}
tls::enter_context(&icx, || f(icx.tcx))
}
}
/// This is used to get a reference to a `GlobalCtxt` if one is available.
///
/// This is needed to allow the deadlock handler access to `GlobalCtxt` to look for query cycles.
/// It cannot use the `TLV` global because that's only guaranteed to be defined on the thread
/// creating the `GlobalCtxt`. Other threads have access to the `TLV` only inside Rayon jobs, but
/// the deadlock handler is not called inside such a job.
#[derive(Clone)]
pub struct CurrentGcx {
/// This stores a pointer to a `GlobalCtxt`. This is set to `Some` inside `GlobalCtxt::enter`
/// and reset to `None` when that function returns or unwinds.
value: Arc<RwLock<Option<*const ()>>>,
}
unsafe impl DynSend for CurrentGcx {}
unsafe impl DynSync for CurrentGcx {}
impl CurrentGcx {
pub fn new() -> Self {
Self { value: Arc::new(RwLock::new(None)) }
}
pub fn access<R>(&self, f: impl for<'tcx> FnOnce(&'tcx GlobalCtxt<'tcx>) -> R) -> R {
let read_guard = self.value.read();
let gcx: *const GlobalCtxt<'_> = read_guard.unwrap() as *const _;
// SAFETY: We hold the read lock for the `GlobalCtxt` pointer. That prevents
// `GlobalCtxt::enter` from returning as it would first acquire the write lock.
// This ensures the `GlobalCtxt` is live during `f`.
f(unsafe { &*gcx })
}
}
impl<'tcx> TyCtxt<'tcx> {
pub fn has_typeck_results(self, def_id: LocalDefId) -> bool {
// Closures' typeck results come from their outermost function,
// as they are part of the same "inference environment".
let root = self.typeck_root_def_id_local(def_id);
self.hir_node_by_def_id(root).body_id().is_some()
}
/// 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::GlobalAsm
) {
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` with alignment 1.
/// Returns the same `AllocId` if called again with the same bytes.
pub fn allocate_bytes_dedup<'a>(
self,
bytes: impl Into<Cow<'a, [u8]>>,
salt: usize,
) -> 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.reserve_and_set_memory_dedup(alloc, salt)
}
/// Traits added on all bounds by default, excluding `Sized` which is treated separately.
pub fn default_traits(self) -> &'static [LangItem] {
if self.sess.opts.unstable_opts.experimental_default_bounds {
&[
LangItem::DefaultTrait1,
LangItem::DefaultTrait2,
LangItem::DefaultTrait3,
LangItem::DefaultTrait4,
]
} else {
&[]
}
}
pub fn is_default_trait(self, def_id: DefId) -> bool {
self.default_traits().iter().any(|&default_trait| self.is_lang_item(def_id, default_trait))
}
pub fn is_sizedness_trait(self, def_id: DefId) -> bool {
matches!(self.as_lang_item(def_id), Some(LangItem::Sized | LangItem::MetaSized))
}
pub fn lift<T: Lift<TyCtxt<'tcx>>>(self, value: T) -> T::Lifted {
value.lift_to_interner(self)
}
/// Creates a type context. To use the context call `fn enter` which
/// provides a `TyCtxt`.
///
/// By only providing the `TyCtxt` inside of the closure we enforce that the type
/// context and any interned value (types, args, 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<T>(
gcx_cell: &'tcx OnceLock<GlobalCtxt<'tcx>>,
sess: &'tcx Session,
crate_types: Vec<CrateType>,
stable_crate_id: StableCrateId,
arena: &'tcx WorkerLocal<Arena<'tcx>>,
hir_arena: &'tcx WorkerLocal<hir::Arena<'tcx>>,
untracked: Untracked,
incr_comp_session: Option<&'tcx IncrCompSession>,
dep_graph: DepGraph,
query_system: QuerySystem<'tcx>,
hooks: crate::hooks::Providers,
current_gcx: CurrentGcx,
f: impl FnOnce(TyCtxt<'tcx>) -> T,
) -> T {
let data_layout = sess.target.parse_data_layout().unwrap_or_else(|err| {
sess.dcx().emit_fatal(err);
});
let interners = CtxtInterners::new(arena);
let common_types = CommonTypes::new(&interners);
let common_lifetimes = CommonLifetimes::new(&interners);
let common_consts = CommonConsts::new(&interners, &common_types);
let gcx = gcx_cell.get_or_init(|| GlobalCtxt {
sess,
crate_types,
stable_crate_id,
arena,
hir_arena,
interners,
incr_comp_session,
dep_graph,
hooks,
prof: sess.prof.clone(),
types: common_types,
lifetimes: common_lifetimes,
consts: common_consts,
untracked,
query_system,
caches: Default::default(),
data_layout,
alloc_map: interpret::AllocMap::new(),
current_gcx,
});
// This is a separate function to work around a crash with parallel rustc (#135870)
gcx.enter(f)
}
/// Obtain all lang items of this crate and all dependencies (recursively)
pub fn lang_items(self) -> &'tcx rustc_attr_ir::lang_items::LanguageItems {
self.get_lang_items(())
}
/// Gets a `Ty` representing the [`LangItem::OrderingEnum`]
#[track_caller]
pub fn ty_ordering_enum(self, span: Span) -> Ty<'tcx> {
let ordering_enum = self.require_lang_item(LangItem::OrderingEnum, span);
self.type_of(ordering_enum).no_bound_vars().unwrap()
}
/// 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)
}
pub fn is_coroutine(self, def_id: DefId) -> bool {
self.coroutine_kind(def_id).is_some()
}
pub fn is_async_drop_in_place_coroutine(self, def_id: DefId) -> bool {
self.is_lang_item(self.parent(def_id), LangItem::AsyncDropInPlace)
}
/// Returns true if the const is guaranteed to have a directly represented RHS. This is either
/// because it has a directly represented RHS, or is a trait definition that is marked as
/// requiring its implementation to have a directly represented RHS.
///
/// Note: Be very careful with using this method - under `generic_const_args`, a trait can
/// declare a regular const, but an `impl` could implement it with a directly represented const
/// (a la refinement). This method would return false in such a case.
pub fn is_direct_const(self, def_id: DefId) -> bool {
debug_assert_matches!(self.def_kind(def_id), DefKind::Const | DefKind::AssocConst);
self.is_always_gca(def_id) || self.const_of_item(def_id).is_some()
}
/// Whether this is a projection const marked with `#[always_gca]`
pub fn is_always_gca(self, def_id: DefId) -> bool {
find_attr!(self, def_id, AlwaysGca)
}
/// Returns the movability of the coroutine of `def_id`, or panics
/// if given a `def_id` that is not a coroutine.
pub fn coroutine_movability(self, def_id: DefId) -> hir::Movability {
self.coroutine_kind(def_id).expect("expected a coroutine").movability()
}
/// Returns `true` if the node pointed to by `def_id` is a coroutine for an async construct.
pub fn coroutine_is_async(self, def_id: DefId) -> bool {
matches!(
self.coroutine_kind(def_id),
Some(hir::CoroutineKind::Desugared(hir::CoroutineDesugaring::Async, _))
)
}
// Whether the body owner is synthetic, which in this case means it does not correspond to
// meaningful HIR. This is currently used to skip over MIR borrowck.
pub fn is_synthetic_mir(self, def_id: impl Into<DefId>) -> bool {
matches!(self.def_kind(def_id.into()), DefKind::SyntheticCoroutineBody)
}
/// Returns `true` if the node pointed to by `def_id` is a general coroutine that implements `Coroutine`.
/// This means it is neither an `async` or `gen` construct.
pub fn is_general_coroutine(self, def_id: DefId) -> bool {
matches!(self.coroutine_kind(def_id), Some(hir::CoroutineKind::Coroutine(_)))
}
/// Returns `true` if the node pointed to by `def_id` is a coroutine for a `gen` construct.
pub fn coroutine_is_gen(self, def_id: DefId) -> bool {
matches!(
self.coroutine_kind(def_id),
Some(hir::CoroutineKind::Desugared(hir::CoroutineDesugaring::Gen, _))
)
}
/// Returns `true` if the node pointed to by `def_id` is a coroutine for a `async gen` construct.
pub fn coroutine_is_async_gen(self, def_id: DefId) -> bool {
matches!(
self.coroutine_kind(def_id),
Some(hir::CoroutineKind::Desugared(hir::CoroutineDesugaring::AsyncGen, _))
)
}
pub fn features(self) -> &'tcx rustc_feature::Features {
self.features_query(())
}
pub fn def_key(self, id: impl IntoQueryKey<DefId>) -> rustc_hir::definitions::DefKey {
let id = id.into_query_key();
// 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 crate_types(self) -> &'tcx [CrateType] {
&self.crate_types
}
pub fn needs_metadata(self) -> bool {
self.crate_types().iter().any(|ty| match *ty {
CrateType::Executable
| CrateType::StaticLib
| CrateType::Cdylib
| CrateType::Sdylib => false,
CrateType::Rlib | CrateType::Dylib | CrateType::ProcMacro => true,
})
}
pub fn needs_hir_hash(self) -> bool {
// Why is the hir hash needed for these configurations?
// - debug_assertions: for the "fingerprint the result" check in
// `rustc_query_impl::execution::execute_job`.
// - incremental: for query lookups.
// - needs_metadata: it is included in the crate metadata through the crate_hash query
// - instrument_coverage: for putting into coverage data (see
// `hash_mir_source`).
// - metrics_dir: metrics use the strict version hash in the filenames
// for dumped metrics files to prevent overwriting distinct metrics
// for similar source builds (may change in the future, this is part
// of the proof of concept impl for the metrics initiative project goal)
cfg!(debug_assertions)
|| self.sess.opts.incremental.is_some()
|| self.needs_metadata()
|| self.sess.instrument_coverage()
|| self.sess.opts.unstable_opts.metrics_dir.is_some()
}
#[inline]
pub fn stable_crate_id(self, crate_num: CrateNum) -> StableCrateId {
if crate_num == LOCAL_CRATE {
self.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.stable_crate_id(LOCAL_CRATE) {
LOCAL_CRATE
} else {
*self
.untracked()
.stable_crate_ids
.read()
.get(&stable_crate_id)
.unwrap_or_else(|| bug!("uninterned StableCrateId: {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) -> Option<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.stable_crate_id(LOCAL_CRATE) {
Some(self.untracked.definitions.read().local_def_path_hash_to_def_id(hash)?.to_def_id())
} else {
self.def_path_hash_to_def_id_extern(hash, stable_crate_id)
}
}
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.stable_crate_id(LOCAL_CRATE))
} 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()
)
}
pub fn dcx(self) -> DiagCtxtHandle<'tcx> {
self.sess.dcx()
}
/// Checks to see if the caller (`body_features`) has all the features required by the callee
/// (`callee_features`).
pub fn is_target_feature_call_safe(
self,
callee_features: &[TargetFeature],
body_features: &[TargetFeature],
) -> bool {
// If the called function has target features the calling function hasn't,
// the call requires `unsafe`. Don't check this on wasm
// targets, though. For more information on wasm see the
// is_like_wasm check in hir_analysis/src/collect.rs
self.sess.target.options.is_like_wasm
|| callee_features
.iter()
.all(|feature| body_features.iter().any(|f| f.name == feature.name))
}
/// Returns the safe version of the signature of the given function, if calling it
/// would be safe in the context of the given caller.
pub fn adjust_target_feature_sig(
self,
fun_def: DefId,
fun_sig: ty::Binder<'tcx, ty::FnSig<'tcx>>,
caller: DefId,
) -> Option<ty::Binder<'tcx, ty::FnSig<'tcx>>> {
let fun_features = &self.codegen_fn_attrs(fun_def).target_features;
let caller_features = &self.body_codegen_attrs(caller).target_features;
if self.is_target_feature_call_safe(&fun_features, &caller_features) {
return Some(fun_sig.map_bound(|sig| ty::FnSig {
fn_sig_kind: fun_sig.fn_sig_kind().set_safety(hir::Safety::Safe),
..sig
}));
}
None
}
/// Helper to get a tracked environment variable via. [`TyCtxt::env_var_os`] and converting to
/// UTF-8 like [`std::env::var`].
pub fn env_var<K: ?Sized + AsRef<OsStr>>(self, key: &'tcx K) -> Result<&'tcx str, VarError> {
match self.env_var_os(key.as_ref()) {
Some(value) => value.to_str().ok_or_else(|| VarError::NotUnicode(value.to_os_string())),
None => Err(VarError::NotPresent),
}
}
pub fn is_method(self, id: DefId) -> bool {
self.opt_associated_item(id).is_some_and(|item| item.is_method())
}
}
impl<'tcx> TyCtxtAt<'tcx> {
/// Create a new definition within the incr. comp. engine.
pub fn create_def(
self,
parent: LocalDefId,
name: Option<Symbol>,
def_kind: DefKind,
override_def_path_data: Option<DefPathData>,
disambiguator: &mut PerParentDisambiguatorState,
) -> TyCtxtFeed<'tcx, LocalDefId> {
let feed =
self.tcx.create_def(parent, name, def_kind, override_def_path_data, disambiguator);
feed.def_span(self.span);
feed
}
}
impl<'tcx> TyCtxt<'tcx> {
/// `tcx`-dependent operations performed for every created definition.
pub fn create_def(
self,
parent: LocalDefId,
name: Option<Symbol>,
def_kind: DefKind,
override_def_path_data: Option<DefPathData>,
disambiguator: &mut PerParentDisambiguatorState,
) -> TyCtxtFeed<'tcx, LocalDefId> {
let data = override_def_path_data.unwrap_or_else(|| def_kind.def_path_data(name));
// 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.
let def_id = self.untracked.definitions.write().create_def(parent, data, disambiguator);
// 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);
let feed = TyCtxtFeed { tcx: self, key: def_id };
feed.def_kind(def_kind);
// Unique types created for closures participate in type privacy checking.
// They have visibilities inherited from the module they are defined in.
// Visibilities for opaque types are meaningless, but still provided
// so that all items have visibilities.
if matches!(def_kind, DefKind::Closure | DefKind::OpaqueTy) {
let parent_mod = self.parent_module_from_def_id(def_id);
feed.visibility(ty::Visibility::Restricted(parent_mod.to_mod_id()));
}
feed
}
pub fn create_crate_num(
self,
stable_crate_id: StableCrateId,
) -> Result<TyCtxtFeed<'tcx, CrateNum>, CrateNum> {
let mut lock = self.untracked().stable_crate_ids.write();
if let Some(&existing) = lock.get(&stable_crate_id) {
return Err(existing);
}
let num = CrateNum::new(lock.len());
lock.insert(stable_crate_id, num);
Ok(TyCtxtFeed { key: num, tcx: self })
}
pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> {
// Depend on the `analysis` query to ensure compilation if finished.
self.ensure_ok().analysis(());
let definitions = &self.untracked.definitions;
gen {
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;
}
// Freeze definitions once we finish iterating on them, to prevent adding new ones.
definitions.freeze();
}
}
pub fn definitions(self) -> &'tcx rustc_hir::definitions::Definitions {
// Depend on the `analysis` query to ensure compilation if finished.
self.ensure_ok().analysis(());
// Freeze definitions once we start iterating on them, to prevent adding new ones
// while iterating. If some query needs to add definitions, it should be `ensure`d above.
self.untracked.definitions.freeze()
}
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_ok().hir_crate_items(());
// Freeze definitions once we start iterating on them, to prevent adding new ones
// while iterating. If some query needs to add definitions, it should be `ensure`d above.
self.untracked.definitions.freeze().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) -> FreezeReadGuard<'tcx, CrateStoreDyn> {
FreezeReadGuard::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) -> FreezeReadGuard<'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(StableHashState<'_>) -> R) -> R {
f(StableHashState::new(self.sess, &self.untracked))
}
#[inline]
pub fn local_crate_exports_generics(self) -> bool {
// compiler-builtins has some special treatment in codegen, which can result in confusing
// behavior if another crate ends up calling into its monomorphizations.
// https://github.com/rust-lang/rust/issues/150173
if self.is_compiler_builtins(LOCAL_CRATE) {
return false;
}
self.crate_types().iter().any(|crate_type| {
match crate_type {
CrateType::Executable
| CrateType::StaticLib
| CrateType::ProcMacro
| CrateType::Cdylib
| CrateType::Sdylib => 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,
generic_param_scope: LocalDefId,
mut region: Region<'tcx>,
) -> Option<FreeRegionInfo> {
let (suitable_region_binding_scope, region_def_id) = loop {
let def_id =
region.opt_param_def_id(self, generic_param_scope.to_def_id())?.as_local()?;
let scope = self.local_parent(def_id);
if self.def_kind(scope) == DefKind::OpaqueTy {
// Lifetime params of opaque types are synthetic and thus irrelevant to
// diagnostics. Map them back to their origin!
region = self.map_opaque_lifetime_to_parent_lifetime(def_id);
continue;
}
break (scope, def_id.into());
};
let is_impl_item = match self.hir_node_by_def_id(suitable_region_binding_scope) {
Node::Item(..) | Node::TraitItem(..) => false,
Node::ImplItem(impl_item) => match impl_item.impl_kind {
// 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.
hir::ImplItemImplKind::Trait { .. } => true,
_ => false,
},
_ => false,
};
Some(FreeRegionInfo { scope: suitable_region_binding_scope, region_def_id, 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.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![]);
v.visit_ty_unambig(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.local_def_id_to_hir_id(scope_def_id);
let mut v = TraitObjectVisitor(vec![]);
// 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_node_by_def_id(local_id).alias_ty() // it is type alias
&& let Some(alias_generics) = self.hir_node_by_def_id(local_id).generics()
{
v.visit_ty_unambig(alias_ty);
if !v.0.is_empty() {
return Some((
v.0,
alias_generics.span,
alias_generics.span_for_lifetime_suggestion(),
));
}
}
None
}
/// 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.llvm_target.starts_with("nvptx")
}
/// Returns `&'static core::panic::Location<'static>`.
pub fn caller_location_ty(self) -> Ty<'tcx> {
Ty::new_imm_ref(
self,
self.lifetimes.re_static,
self.type_of(self.require_lang_item(LangItem::PanicLocation, DUMMY_SP))
.instantiate(self, self.mk_args(&[self.lifetimes.re_static.into()]))
.skip_norm_wip(),
)
}
/// 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 pattern_complexity_limit(self) -> Limit {
self.limits(()).pattern_complexity_limit
}
/// All traits in the crate graph, including those not visible to the user.
pub fn all_traits_including_private(self) -> impl Iterator<Item = DefId> {
iter::once(LOCAL_CRATE)
.chain(self.crates(()).iter().copied())
.flat_map(move |cnum| self.traits(cnum).iter().copied())
}
/// All traits that are visible within the crate graph (i.e. excluding private dependencies).
pub fn visible_traits(self) -> impl Iterator<Item = DefId> {
let visible_crates =
self.crates(()).iter().copied().filter(move |cnum| self.is_user_visible_dep(*cnum));
iter::once(LOCAL_CRATE)
.chain(visible_crates)
.flat_map(move |cnum| self.traits(cnum).iter().copied())
}
#[inline]
pub fn local_visibility(self, def_id: LocalDefId) -> Visibility {
self.visibility(def_id).expect_local()
}
/// Returns the origin of the opaque type `def_id`.
#[instrument(skip(self), level = "trace", ret)]
pub fn local_opaque_ty_origin(self, def_id: LocalDefId) -> hir::OpaqueTyOrigin<LocalDefId> {
self.hir_expect_opaque_ty(def_id).origin
}
pub fn finish(self) {
// We assume that no queries are run past here. If there are new queries
// after this point, they'll show up as "<unknown>" in self-profiling data.
self.alloc_self_profile_query_strings();
self.save_dep_graph();
self.verify_query_key_hashes();
if let Err((path, error)) = self.dep_graph.finish_encoding() {
self.sess
.dcx()
.emit_fatal(crate::diagnostics::FailedWritingFile { path: &path, error });
}
}
pub fn report_unused_features(self) {
#[derive(Diagnostic)]
#[diag("feature `{$feature}` is declared but not used")]
struct UnusedFeature {
feature: Symbol,
}
// Collect first to avoid holding the lock while linting.
let used_features = self.query_system.used_features.lock();
let unused_features = self
.features()
.enabled_features_iter_stable_order()
.filter(|(f, _)| {
!used_features.contains_key(f)
// FIXME: `restricted_std` is used to tell a standard library built
// for a platform that it doesn't know how to support. But it
// could only gate a private mod (see `__restricted_std_workaround`)
// with `cfg(not(restricted_std))`, so it cannot be recorded as used
// in downstream crates. It should never be linted, but should we
// hack this in the linter to ignore it?
&& f.as_str() != "restricted_std"
// `doc_cfg` affects rustdoc behavior: rustdoc checks it via
// `tcx.features().doc_cfg()`, but a normal rustc compilation may
// never observe that use. Do not lint it as unused here.
&& *f != sym::doc_cfg
})
.collect::<Vec<_>>();
for (feature, span) in unused_features {
self.emit_node_span_lint(
UNUSED_FEATURES,
CRATE_HIR_ID,
span,
UnusedFeature { feature },
);
}
}
}
macro_rules! nop_lift {
($set:ident; $ty:ty => $lifted:ty) => {
impl<'a, 'tcx> Lift<TyCtxt<'tcx>> for $ty {
type Lifted = $lifted;
#[track_caller]
fn lift_to_interner(self, tcx: TyCtxt<'tcx>) -> Self::Lifted {
// Assert that the set has the right type.
// Given an argument that has an interned type, the return type has the type of
// the corresponding interner set. This won't actually return anything, we're
// just doing this to compute said type!
fn _intern_set_ty_from_interned_ty<'tcx, Inner>(
_x: Interned<'tcx, Inner>,
) -> InternedSet<'tcx, Inner> {
unreachable!()
}
fn _type_eq<T>(_x: &T, _y: &T) {}
fn _test<'tcx>(x: $lifted, tcx: TyCtxt<'tcx>) {
// If `x` is a newtype around an `Interned<T>`, then `interner` is an
// interner of appropriate type. (Ideally we'd also check that `x` is a
// newtype with just that one field. Not sure how to do that.)
let interner = _intern_set_ty_from_interned_ty(x.0);
// Now check that this is the same type as `interners.$set`.
_type_eq(&interner, &tcx.interners.$set);
}
assert!(tcx.interners.$set.contains_pointer_to(&InternedInSet(&*self.0.0)));
// SAFETY: we just checked that `self` is interned and therefore is valid for the
// entire lifetime of the `TyCtxt`.
unsafe { mem::transmute(self) }
}
}
};
}
macro_rules! nop_list_lift {
($set:ident; $ty:ty => $lifted:ty) => {
nop_list_lift! { $set: List; $ty => $lifted }
};
// Allows defining own list type
($set:ident: $list:ident; $ty:ty => $lifted:ty) => {
impl<'a, 'tcx> Lift<TyCtxt<'tcx>> for &'a $list<$ty> {
type Lifted = &'tcx $list<$lifted>;
fn lift_to_interner(self, tcx: TyCtxt<'tcx>) -> Self::Lifted {
// Assert that the set has the right type.
if false {
let _x: &InternedSet<'tcx, $list<$lifted>> = &tcx.interners.$set;
}
if self.is_empty() {
return $list::empty();
}
assert!(tcx.interners.$set.contains_pointer_to(&InternedInSet(self)));
// SAFETY: we just checked that `self` is interned and therefore is valid for the
// entire lifetime of the `TyCtxt`.
unsafe { mem::transmute(self) }
}
}
};
}
nop_lift! { type_; Ty<'a> => Ty<'tcx> }
nop_lift! { pat; Pattern<'a> => Pattern<'tcx> }
nop_lift! { const_allocation; ConstAllocation<'a> => ConstAllocation<'tcx> }
nop_lift! { predicate; Predicate<'a> => Predicate<'tcx> }
nop_lift! { predicate; Clause<'a> => Clause<'tcx> }
nop_lift! { layout; Layout<'a> => Layout<'tcx> }
nop_lift! { valtree; ValTree<'a> => ValTree<'tcx> }
impl<'a, 'tcx> Lift<TyCtxt<'tcx>> for Interned<'a, RegionKind<'a>> {
type Lifted = Interned<'tcx, RegionKind<'tcx>>;
#[track_caller]
fn lift_to_interner(self, tcx: TyCtxt<'tcx>) -> Self::Lifted {
assert!(tcx.interners.region.contains_pointer_to(&InternedInSet(&*self.0)));
// SAFETY: we just checked that `self` is interned in this `TyCtxt`, so
// its pointee is valid for the entire lifetime of the target `TyCtxt`.
unsafe { mem::transmute(self) }
}
}
// FIXME: unclear why exactly the macro doesn't work.
impl<'a, 'tcx> Lift<TyCtxt<'tcx>> for Interned<'a, WithCachedTypeInfo<ConstKind<'a>>> {
type Lifted = Interned<'tcx, WithCachedTypeInfo<ConstKind<'tcx>>>;
#[track_caller]
fn lift_to_interner(self, tcx: TyCtxt<'tcx>) -> Self::Lifted {
assert!(tcx.interners.const_.contains_pointer_to(&InternedInSet(&*self.0)));
// SAFETY: we just checked that `self` is interned in this `TyCtxt`, so
// its pointee is valid for the entire lifetime of the target `TyCtxt`.
unsafe { mem::transmute(self) }
}
}
nop_list_lift! { type_lists; Ty<'a> => Ty<'tcx> }
nop_list_lift! { clauses: ListWithCachedTypeInfo; Clause<'a> => Clause<'tcx> }
nop_list_lift! {
poly_existential_predicates; PolyExistentialPredicate<'a> => PolyExistentialPredicate<'tcx>
}
nop_list_lift! { bound_variable_kinds; ty::BoundVariableKind<'a> => ty::BoundVariableKind<'tcx> }
nop_list_lift! { patterns; Pattern<'a> => Pattern<'tcx> }
nop_list_lift! { outlives; ty::ArgOutlivesClause<'a> => ty::ArgOutlivesClause<'tcx> }
// This is the impl for `&'a GenericArgs<'a>`.
nop_list_lift! { args; GenericArg<'a> => GenericArg<'tcx> }
macro_rules! sty_debug_print {
($fmt: expr, $ctxt: expr, $($variant: ident),*) => {{
#[allow(non_snake_case, reason = "we're using variant names as local variables")]
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(crate) 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;)*
for shard in tcx.interners.type_.lock_shards() {
// It seems that ordering doesn't affect anything here.
#[allow(rustc::potential_query_instability)]
let types = shard.iter();
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 fmt::Debug {
fmt::from_fn(move |fmt| {
sty_debug_print!(
fmt,
self,
Adt,
Array,
Slice,
RawPtr,
Ref,
FnDef,
FnPtr,
UnsafeBinder,
Placeholder,
Coroutine,
CoroutineWitness,
Dynamic,
Closure,
CoroutineClosure,
Tuple,
Bound,
Param,
Infer,
Alias,
Pat,
Foreign
)?;
writeln!(fmt, "GenericArgs interner: #{}", self.interners.args.len())?;
writeln!(fmt, "Region interner: #{}", self.interners.region.len())?;
writeln!(fmt, "Const Allocation interner: #{}", self.interners.const_allocation.len())?;
writeln!(fmt, "Layout interner: #{}", self.interners.layout.len())?;
Ok(())
})
}
}
// 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 + PointeeSized>(&'tcx T);
impl<'tcx, T: 'tcx + ?Sized + PointeeSized> Clone for InternedInSet<'tcx, T> {
fn clone(&self) -> Self {
*self
}
}
impl<'tcx, T: 'tcx + ?Sized + PointeeSized> Copy for InternedInSet<'tcx, T> {}
impl<'tcx, T: 'tcx + ?Sized + PointeeSized> 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)
}
}
impl<'tcx, T> Borrow<[T]> for InternedInSet<'tcx, ListWithCachedTypeInfo<T>> {
fn borrow(&self) -> &[T] {
&self.0[..]
}
}
impl<'tcx, T: PartialEq> PartialEq for InternedInSet<'tcx, ListWithCachedTypeInfo<T>> {
fn eq(&self, other: &InternedInSet<'tcx, ListWithCachedTypeInfo<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, ListWithCachedTypeInfo<T>> {}
impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, ListWithCachedTypeInfo<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
// crate only, and have a corresponding `mk_` function.
direct_interners! {
region: pub(crate) intern_region(RegionKind<'tcx>): Region -> Region<'tcx>,
valtree: pub(crate) intern_valtree(ValTreeKind<TyCtxt<'tcx>>): ValTree -> ValTree<'tcx>,
pat: pub mk_pat(PatternKind<'tcx>): Pattern -> Pattern<'tcx>,
const_allocation: pub mk_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
layout: pub mk_layout(LayoutData<FieldIdx, VariantIdx>): Layout -> Layout<'tcx>,
adt_def: pub mk_adt_def_from_data(AdtDefData): AdtDef -> AdtDef<'tcx>,
external_constraints: pub mk_external_constraints(ExternalConstraintsData<TyCtxt<'tcx>>):
ExternalConstraints -> ExternalConstraints<'tcx>,
canonical_inputs: intern_canonical_input(CanonicalInputData<TyCtxt<'tcx>>): CanonicalInput -> CanonicalInput<'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>),
args: pub mk_args(GenericArg<'tcx>),
type_lists: pub mk_type_list(Ty<'tcx>),
canonical_var_kinds: pub mk_canonical_var_kinds(CanonicalVarKind<'tcx>),
poly_existential_predicates: intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
projs: pub mk_projs(ProjectionKind),
place_elems: pub mk_place_elems(PlaceElem<'tcx>),
bound_variable_kinds: pub mk_bound_variable_kinds(ty::BoundVariableKind<'tcx>),
fields: pub mk_fields(FieldIdx),
local_def_ids: intern_local_def_ids(LocalDefId),
captures: intern_captures(&'tcx ty::CapturedPlace<'tcx>),
patterns: pub mk_patterns(Pattern<'tcx>),
outlives: pub mk_outlives(ty::ArgOutlivesClause<'tcx>),
predefined_opaques_in_body: pub mk_predefined_opaques_in_body((ty::OpaqueTypeKey<'tcx>, Ty<'tcx>)),
);
impl<'tcx> TyCtxt<'tcx> {
/// Given a `fn` sig, 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!(sig.safety().is_safe());
Ty::new_fn_ptr(
self,
sig.map_bound(|sig| ty::FnSig {
fn_sig_kind: sig.fn_sig_kind.set_safety(hir::Safety::Unsafe),
..sig
}),
)
}
/// Given a `fn` sig, returns an equivalent `unsafe fn` sig;
/// that is, a `fn` sig that is equivalent in every way for being
/// unsafe.
pub fn safe_to_unsafe_sig(self, sig: PolyFnSig<'tcx>) -> PolyFnSig<'tcx> {
assert!(sig.safety().is_safe());
sig.map_bound(|sig| ty::FnSig {
fn_sig_kind: sig.fn_sig_kind.set_safety(hir::Safety::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 {
elaborate::supertrait_def_ids(self, 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::AliasTy { kind: ty::Opaque { def_id }, .. }) = *ty.kind() else {
return false;
};
let future_trait = self.require_lang_item(LangItem::Future, DUMMY_SP);
self.explicit_item_self_bounds(def_id).skip_binder().iter().any(|&(predicate, _)| {
let ty::ClauseKind::Trait(trait_predicate) = predicate.kind().skip_binder() else {
return false;
};
trait_predicate.trait_ref.def_id == future_trait
&& trait_predicate.polarity == ClausePolarity::Positive
})
}
/// 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::Safety::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>, safety: hir::Safety) -> PolyFnSig<'tcx> {
sig.map_bound(|s| {
let params = match s.inputs()[0].kind() {
ty::Tuple(params) => *params,
_ => bug!(),
};
// Ignore splatting, it is unsupported on closures.
assert!(s.splatted().is_none());
self.mk_fn_sig(
params,
s.output(),
s.fn_sig_kind.set_safety(safety).set_abi(ExternAbi::Rust),
)
})
}
#[inline]
pub fn mk_predicate(self, binder: Binder<'tcx, PredicateKind<'tcx>>) -> Predicate<'tcx> {
self.interners.intern_predicate(binder)
}
#[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 }
}
/// If you have a [`ty::Alias`], you should almost certainly be calling
/// [`Self::check_alias_term_args_compatible`] instead. This method assumes that inherent alias
/// consts always have `impl`-form args, and will return an invalid result if the `def_id` comes
/// from a [`ty::AliasConstKind::InherentSelf`] (see the doc on that for what "impl form args"
/// means).
pub fn check_args_compatible(self, def_id: DefId, args: &'tcx [ty::GenericArg<'tcx>]) -> bool {
let is_inherent_assoc_ty = matches!(self.def_kind(def_id), DefKind::AssocTy)
&& matches!(self.def_kind(self.parent(def_id)), DefKind::Impl { of_trait: false });
self.check_args_compatible_inner(def_id, args, is_inherent_assoc_ty)
}
pub fn check_alias_term_args_compatible(
self,
kind: ty::AliasTermKind<'tcx>,
args: &'tcx [ty::GenericArg<'tcx>],
) -> bool {
let (def_id, is_self_args) = match kind {
ty::AliasTermKind::ProjectionTy { def_id }
| ty::AliasTermKind::OpaqueTy { def_id }
| ty::AliasTermKind::FreeTy { def_id }
| ty::AliasTermKind::AnonConst { def_id }
| ty::AliasTermKind::ProjectionConst { def_id }
| ty::AliasTermKind::FreeConst { def_id }
| ty::AliasTermKind::InherentConstImpl { def_id } => (def_id, false),
ty::AliasTermKind::InherentTy { def_id }
| ty::AliasTermKind::InherentConstSelf { def_id } => (def_id, true),
};
self.check_args_compatible_inner(def_id, args, is_self_args)
}
fn check_args_compatible_inner(
self,
def_id: DefId,
args: &'tcx [ty::GenericArg<'tcx>],
is_self_args: bool,
) -> bool {
let generics = self.generics_of(def_id);
let own_args = if is_self_args {
if generics.own_params.len() + 1 != args.len() {
return false;
}
if !matches!(args[0].kind(), ty::GenericArgKind::Type(_)) {
return false;
}
&args[1..]
} else {
if generics.count() != args.len() {
return false;
}
let (parent_args, own_args) = args.split_at(generics.parent_count);
// In the type system, IATs and IACs (inherent associated types/consts) themselves have a
// weird arg setup (self + own args), but nested items *in* IATs (namely: opaques, i.e.
// ATPITs) do not. So, set `is_self_args` to false for the parent generic check.
if let Some(parent) = generics.parent
&& !self.check_args_compatible_inner(parent, parent_args, false)
{
return false;
}
own_args
};
for (param, arg) in std::iter::zip(&generics.own_params, own_args) {
match (&param.kind, arg.kind()) {
(ty::GenericParamDefKind::Type { .. }, ty::GenericArgKind::Type(_))
| (ty::GenericParamDefKind::Lifetime, ty::GenericArgKind::Lifetime(_))
| (ty::GenericParamDefKind::Const { .. }, ty::GenericArgKind::Const(_)) => {}
_ => return false,
}
}
true
}
/// With `cfg(debug_assertions)`, assert that args are compatible with their generics,
/// and print out the args if not.
///
/// If you have a [`ty::Alias`], you should use
/// [`Self::debug_assert_alias_term_args_compatible`] instead. See note on
/// [`Self::check_args_compatible`].
pub fn debug_assert_args_compatible(self, def_id: DefId, args: &'tcx [ty::GenericArg<'tcx>]) {
if cfg!(debug_assertions) && !self.check_args_compatible(def_id, args) {
let is_inherent_assoc_ty = matches!(self.def_kind(def_id), DefKind::AssocTy)
&& matches!(self.def_kind(self.parent(def_id)), DefKind::Impl { of_trait: false });
self.emit_bug_args_compatible(def_id, args, is_inherent_assoc_ty);
}
}
pub fn debug_assert_alias_term_args_compatible(
self,
kind: ty::AliasTermKind<'tcx>,
args: ty::GenericArgsRef<'tcx>,
) {
if cfg!(debug_assertions) {
self.debug_assert_alias_term_kind_matches_def_kind(kind);
if !self.check_alias_term_args_compatible(kind, args) {
let (def_id, is_self_args) = match kind {
ty::AliasTermKind::ProjectionTy { def_id }
| ty::AliasTermKind::OpaqueTy { def_id }
| ty::AliasTermKind::FreeTy { def_id }
| ty::AliasTermKind::AnonConst { def_id }
| ty::AliasTermKind::ProjectionConst { def_id }
| ty::AliasTermKind::FreeConst { def_id }
| ty::AliasTermKind::InherentConstImpl { def_id } => (def_id, false),
ty::AliasTermKind::InherentTy { def_id }
| ty::AliasTermKind::InherentConstSelf { def_id } => (def_id, true),
};
self.emit_bug_args_compatible(def_id, args, is_self_args);
}
}
}
fn debug_assert_alias_term_kind_matches_def_kind(self, kind: ty::AliasTermKind<'tcx>) {
match kind {
ty::AliasTermKind::ProjectionTy { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::AssocTy);
debug_assert_matches!(
self.def_kind(self.parent(def_id)),
DefKind::Trait | DefKind::Impl { of_trait: true }
);
}
ty::AliasTermKind::InherentTy { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::AssocTy);
debug_assert_matches!(
self.def_kind(self.parent(def_id)),
DefKind::Impl { of_trait: false }
);
}
ty::AliasTermKind::OpaqueTy { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::OpaqueTy);
}
ty::AliasTermKind::FreeTy { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::TyAlias);
}
ty::AliasTermKind::AnonConst { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::AnonConst);
}
ty::AliasTermKind::ProjectionConst { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::AssocConst);
debug_assert_matches!(
self.def_kind(self.parent(def_id)),
DefKind::Trait | DefKind::Impl { of_trait: true }
);
}
ty::AliasTermKind::InherentConstSelf { def_id }
| ty::AliasTermKind::InherentConstImpl { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::AssocConst);
debug_assert_matches!(
self.def_kind(self.parent(def_id)),
DefKind::Impl { of_trait: false }
);
}
ty::AliasTermKind::FreeConst { def_id } => {
debug_assert_matches!(self.def_kind(def_id), DefKind::Const);
}
}
}
fn emit_bug_args_compatible(
self,
def_id: DefId,
args: &'tcx [ty::GenericArg<'tcx>],
is_self_args: bool,
) -> ! {
if is_self_args {
bug!(
"args not compatible with generics for {}: args={:#?}, generics={:#?}",
self.def_path_str(def_id),
args,
// Make `[Self, GAT_ARGS...]` (this could be simplified)
self.mk_args_from_iter(
[self.types.self_param.into()].into_iter().chain(
self.generics_of(def_id)
.own_args(ty::GenericArgs::identity_for_item(self, def_id))
.iter()
.copied()
)
)
);
} else {
bug!(
"args not compatible with generics for {}: args={:#?}, generics={:#?}",
self.def_path_str(def_id),
args,
ty::GenericArgs::identity_for_item(self, def_id)
);
}
}
#[inline(always)]
pub(crate) fn check_and_mk_args(
self,
def_id: DefId,
args: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
) -> GenericArgsRef<'tcx> {
let args = self.mk_args_from_iter(args.into_iter().map(Into::into));
self.debug_assert_args_compatible(def_id, args);
args
}
#[inline]
pub fn mk_ct_from_kind(self, kind: ty::ConstKind<'tcx>) -> Const<'tcx> {
self.interners.intern_const(kind)
}
// Avoid this in favour of more specific `Ty::new_*` 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)
}
pub fn mk_param_from_def(self, param: &ty::GenericParamDef) -> GenericArg<'tcx> {
match param.kind {
GenericParamDefKind::Lifetime => {
ty::Region::new_early_param(self, param.to_early_bound_region_data()).into()
}
GenericParamDefKind::Type { .. } => Ty::new_param(self, param.index, param.name).into(),
GenericParamDefKind::Const { .. } => {
ty::Const::new_param(self, ParamConst { index: param.index, name: param.name })
.into()
}
}
}
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> {
Place {
local: place.local,
projection: self.mk_place_elems_from_iter(place.projection.iter().chain([elem])),
}
}
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_clauses(self, clauses: &[Clause<'tcx>]) -> Clauses<'tcx> {
// FIXME consider asking the input slice to be sorted to avoid
// re-interning permutations, in which case that would be asserted
// here.
self.interners.intern_clauses(clauses)
}
pub fn mk_local_def_ids(self, def_ids: &[LocalDefId]) -> &'tcx List<LocalDefId> {
// FIXME consider asking the input slice to be sorted to avoid
// re-interning permutations, in which case that would be asserted
// here.
self.intern_local_def_ids(def_ids)
}
pub fn mk_patterns_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<ty::Pattern<'tcx>, &'tcx List<ty::Pattern<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_patterns(xs))
}
pub fn mk_local_def_ids_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<LocalDefId, &'tcx List<LocalDefId>>,
{
T::collect_and_apply(iter, |xs| self.mk_local_def_ids(xs))
}
pub fn mk_captures_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<
&'tcx ty::CapturedPlace<'tcx>,
&'tcx List<&'tcx ty::CapturedPlace<'tcx>>,
>,
{
T::collect_and_apply(iter, |xs| self.intern_captures(xs))
}
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,
fn_sig_kind: FnSigKind<'tcx>,
) -> 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),
fn_sig_kind,
})
}
/// `mk_fn_sig`, but with a Rust ABI, and no C-variadic argument.
pub fn mk_fn_sig_rust_abi<I, T>(
self,
inputs: I,
output: I::Item,
safety: hir::Safety,
) -> T::Output
where
I: IntoIterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, ty::FnSig<'tcx>>,
{
self.mk_fn_sig(inputs, output, FnSigKind::default().set_safety(safety))
}
/// `mk_fn_sig`, but with a safe Rust ABI, and no C-variadic argument.
pub fn mk_fn_sig_safe_rust_abi<I, T>(self, inputs: I, output: I::Item) -> T::Output
where
I: IntoIterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, ty::FnSig<'tcx>>,
{
self.mk_fn_sig(inputs, output, FnSigKind::default().set_safety(hir::Safety::Safe))
}
/// `mk_fn_sig`, but with an **un**safe Rust ABI, and no C-variadic argument.
pub fn mk_fn_sig_unsafe_rust_abi<I, T>(self, inputs: I, output: I::Item) -> T::Output
where
I: IntoIterator<Item = T>,
T: CollectAndApply<Ty<'tcx>, ty::FnSig<'tcx>>,
{
self.mk_fn_sig(inputs, output, FnSigKind::default().set_safety(hir::Safety::Unsafe))
}
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_predefined_opaques_in_body_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<(ty::OpaqueTypeKey<'tcx>, Ty<'tcx>), PredefinedOpaques<'tcx>>,
{
T::collect_and_apply(iter, |xs| self.mk_predefined_opaques_in_body(xs))
}
pub fn mk_clauses_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<Clause<'tcx>, Clauses<'tcx>>,
{
T::collect_and_apply(iter, |xs| self.mk_clauses(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_args_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<GenericArg<'tcx>, ty::GenericArgsRef<'tcx>>,
{
T::collect_and_apply(iter, |xs| self.mk_args(xs))
}
pub fn mk_canonical_var_infos_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<CanonicalVarKind<'tcx>, &'tcx List<CanonicalVarKind<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_canonical_var_kinds(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_args_trait(
self,
self_ty: Ty<'tcx>,
rest: impl IntoIterator<Item = GenericArg<'tcx>>,
) -> GenericArgsRef<'tcx> {
self.mk_args_from_iter(iter::once(self_ty.into()).chain(rest))
}
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>, &'tcx List<ty::BoundVariableKind<'tcx>>>,
{
T::collect_and_apply(iter, |xs| self.mk_bound_variable_kinds(xs))
}
pub fn mk_outlives_from_iter<I, T>(self, iter: I) -> T::Output
where
I: Iterator<Item = T>,
T: CollectAndApply<
ty::ArgOutlivesClause<'tcx>,
&'tcx ty::List<ty::ArgOutlivesClause<'tcx>>,
>,
{
T::collect_and_apply(iter, |xs| self.mk_outlives(xs))
}
/// Emit a lint at `span` from a lint struct (some type that implements `Diagnostic`,
/// typically generated by `#[derive(Diagnostic)]`).
#[track_caller]
pub fn emit_node_span_lint(
self,
lint: &'static Lint,
hir_id: HirId,
span: impl Into<MultiSpan>,
decorator: impl for<'a> Diagnostic<'a>,
) {
let level_spec = self.lint_level_spec_at_node(lint, hir_id);
emit_lint_base(self.sess, lint, level_spec, Some(span.into()), decorator)
}
/// Find the appropriate span where `use` and outer attributes can be inserted at.
pub fn crate_level_attribute_injection_span(self) -> Span {
let node = self.hir_node(hir::CRATE_HIR_ID);
let hir::Node::Crate(m) = node else { bug!() };
m.spans.inject_use_span.shrink_to_lo()
}
pub fn disabled_nightly_features(
self,
diag: &mut Diag<'_>,
features: impl IntoIterator<Item = (String, Symbol)>,
) {
if !self.sess.is_nightly_build() {
return;
}
let span = self.crate_level_attribute_injection_span();
for (desc, feature) in features {
// FIXME: make this string translatable
let msg =
format!("add `#![feature({feature})]` to the crate attributes to enable{desc}");
diag.span_suggestion_verbose(
span,
msg,
format!("#![feature({feature})]\n"),
Applicability::MaybeIncorrect,
);
}
}
/// Emit a lint from a lint struct (some type that implements `Diagnostic`, typically generated
/// by `#[derive(Diagnostic)]`).
#[track_caller]
pub fn emit_node_lint(
self,
lint: &'static Lint,
id: HirId,
decorator: impl for<'a> Diagnostic<'a>,
) {
let level_spec = self.lint_level_spec_at_node(lint, id);
emit_lint_base(self.sess, lint, level_spec, None, decorator);
}
pub fn in_scope_traits(self, id: HirId) -> Option<&'tcx [TraitCandidate<'tcx>]> {
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).get(&id.local_id).cloned()
}
pub fn is_late_bound(self, id: HirId) -> bool {
self.is_late_bound_map(id.owner).is_some_and(|set| set.contains(&id.local_id))
}
pub fn late_bound_vars(self, id: HirId) -> &'tcx List<ty::BoundVariableKind<'tcx>> {
self.mk_bound_variable_kinds(
&self
.late_bound_vars_map(id.owner)
.get(&id.local_id)
.cloned()
.unwrap_or_else(|| bug!("No bound vars found for {}", self.hir_id_to_string(id))),
)
}
/// Given the def-id of an early-bound lifetime on an opaque corresponding to
/// a duplicated captured lifetime, map it back to the early- or late-bound
/// lifetime of the function from which it originally as captured. If it is
/// a late-bound lifetime, this will represent the liberated (`ReLateParam`) lifetime
/// of the signature.
// FIXME(RPITIT): if we ever synthesize new lifetimes for RPITITs and not just
// re-use the generics of the opaque, this function will need to be tweaked slightly.
pub fn map_opaque_lifetime_to_parent_lifetime(
self,
mut opaque_lifetime_param_def_id: LocalDefId,
) -> ty::Region<'tcx> {
debug_assert!(
matches!(self.def_kind(opaque_lifetime_param_def_id), DefKind::LifetimeParam),
"{opaque_lifetime_param_def_id:?} is a {}",
self.def_descr(opaque_lifetime_param_def_id.to_def_id())
);
loop {
let parent = self.local_parent(opaque_lifetime_param_def_id);
let lifetime_mapping = self.opaque_captured_lifetimes(parent);
let Some((lifetime, _)) = lifetime_mapping
.iter()
.find(|(_, duplicated_param)| *duplicated_param == opaque_lifetime_param_def_id)
else {
bug!("duplicated lifetime param should be present");
};
match *lifetime {
resolve_bound_vars::ResolvedArg::EarlyBound(ebv) => {
let new_parent = self.local_parent(ebv);
// If we map to another opaque, then it should be a parent
// of the opaque we mapped from. Continue mapping.
if matches!(self.def_kind(new_parent), DefKind::OpaqueTy) {
debug_assert_eq!(self.local_parent(parent), new_parent);
opaque_lifetime_param_def_id = ebv;
continue;
}
let generics = self.generics_of(new_parent);
return ty::Region::new_early_param(
self,
ty::EarlyParamRegion {
index: generics
.param_def_id_to_index(self, ebv.to_def_id())
.expect("early-bound var should be present in fn generics"),
name: self.item_name(ebv.to_def_id()),
},
);
}
resolve_bound_vars::ResolvedArg::LateBound(_, _, lbv) => {
let new_parent = self.local_parent(lbv);
return ty::Region::new_late_param(
self,
new_parent.to_def_id(),
ty::LateParamRegionKind::Named(lbv.to_def_id()),
);
}
resolve_bound_vars::ResolvedArg::Error(guar) => {
return ty::Region::new_error(self, guar);
}
_ => {
return ty::Region::new_error_with_message(
self,
self.def_span(opaque_lifetime_param_def_id),
"cannot resolve lifetime",
);
}
}
}
}
/// Whether `def_id` is a stable const fn (i.e., doesn't need any feature gates to be called).
///
/// When this is `false`, the function may still be callable as a `const fn` due to features
/// being enabled!
pub fn is_stable_const_fn(self, def_id: DefId) -> bool {
self.is_const_fn(def_id)
&& match self.lookup_const_stability(def_id) {
None => true, // a fn in a non-staged_api crate
Some(stability) if stability.is_const_stable() => true,
_ => false,
}
}
/// Whether the trait impl is marked const. This does not consider stability or feature gates.
pub fn is_const_trait_impl(self, def_id: DefId) -> bool {
self.def_kind(def_id) == DefKind::Impl { of_trait: true }
&& matches!(
self.impl_trait_header(def_id).constness,
hir::Constness::Const { always: false }
)
}
pub fn is_sdylib_interface_build(self) -> bool {
self.sess.opts.unstable_opts.build_sdylib_interface
}
pub fn intrinsic(self, def_id: impl IntoQueryKey<DefId>) -> Option<ty::IntrinsicDef> {
let def_id = def_id.into_query_key();
match self.def_kind(def_id) {
DefKind::Fn | DefKind::AssocFn => self.intrinsic_raw(def_id),
_ => None,
}
}
pub fn next_trait_solver_globally(self) -> bool {
self.sess.opts.unstable_opts.next_solver.globally && !self.features().generic_const_exprs()
}
pub fn next_trait_solver_in_coherence(self) -> bool {
self.sess.opts.unstable_opts.next_solver.coherence
}
pub fn disable_trait_solver_fast_paths(self) -> bool {
self.sess.opts.unstable_opts.disable_fast_paths
}
pub fn disable_param_env_normalization_hack(self) -> bool {
self.sess.opts.unstable_opts.disable_param_env_normalization_hack
}
pub fn renormalize_rigid_aliases(self) -> bool {
self.sess.opts.unstable_opts.renormalize_rigid_aliases
}
#[allow(rustc::bad_opt_access)]
pub fn use_typing_mode_post_typeck_until_borrowck(self) -> bool {
self.next_trait_solver_globally()
|| self.sess.opts.unstable_opts.typing_mode_post_typeck_until_borrowck
}
pub fn assumptions_on_binders(self) -> bool {
self.sess.opts.unstable_opts.assumptions_on_binders
}
pub fn is_impl_trait_in_trait(self, def_id: DefId) -> bool {
self.opt_rpitit_info(def_id).is_some()
}
pub fn get_impl_future_output_ty(self, ty: Ty<'tcx>) -> Option<Ty<'tcx>> {
let (def_id, args) = match *ty.kind() {
ty::Alias(_, ty::AliasTy { kind: ty::Opaque { def_id }, args, .. }) => (def_id, args),
ty::Alias(_, ty::AliasTy { kind: ty::Projection { def_id }, args, .. })
if self.is_impl_trait_in_trait(def_id) =>
{
(def_id, args)
}
_ => return None,
};
let future_trait = self.require_lang_item(LangItem::Future, DUMMY_SP);
let item_def_id = self.associated_item_def_ids(future_trait)[0];
self.explicit_item_self_bounds(def_id)
.iter_instantiated_copied(self, args)
.map(ty::Unnormalized::skip_norm_wip)
.find_map(|(predicate, _)| {
predicate
.kind()
.map_bound(|kind| match kind {
ty::ClauseKind::Projection(projection_predicate)
if projection_predicate.def_id() == item_def_id =>
{
projection_predicate.term.as_type()
}
_ => None,
})
.no_bound_vars()
.flatten()
})
}
/// 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[..])
}
/// Return the crate imported by given use item.
pub fn extern_mod_stmt_cnum(self, def_id: LocalDefId) -> Option<CrateNum> {
self.resolutions(()).extern_crate_map.get(&def_id).copied()
}
pub fn resolver_for_lowering(
self,
) -> (&'tcx Steal<ResolverAstLowering<'tcx>>, &'tcx Steal<ast::Crate>) {
let (resolver, krate, _) = self.resolver_for_lowering_raw(());
(resolver, krate)
}
pub fn metadata_dep_node(self) -> crate::dep_graph::DepNode {
make_metadata(self)
}
pub fn needs_coroutine_by_move_body_def_id(self, def_id: DefId) -> bool {
if let Some(hir::CoroutineKind::Desugared(_, hir::CoroutineSource::Closure)) =
self.coroutine_kind(def_id)
&& let ty::Coroutine(_, args) =
self.type_of(def_id).instantiate_identity().skip_norm_wip().kind()
&& args.as_coroutine().kind_ty().to_opt_closure_kind() != Some(ty::ClosureKind::FnOnce)
{
true
} else {
false
}
}
/// Whether this is a trait implementation that has `#[diagnostic::do_not_recommend]`
pub fn do_not_recommend_impl(self, def_id: DefId) -> bool {
find_attr!(self, def_id, DoNotRecommend)
}
pub fn is_trivial_const(self, def_id: impl IntoQueryKey<DefId>) -> bool {
let def_id = def_id.into_query_key();
self.trivial_const(def_id).is_some()
}
/// Whether this def is one of the special bin crate entrypoint functions that must have a
/// monomorphization and also not be internalized in the bin crate.
pub fn is_entrypoint(self, def_id: DefId) -> bool {
if self.is_lang_item(def_id, LangItem::Start) {
return true;
}
if let Some((entry_def_id, _)) = self.entry_fn(())
&& entry_def_id == def_id
{
return true;
}
false
}
}
pub fn provide(providers: &mut Providers) {
providers.is_panic_runtime = |tcx, LocalCrate| find_attr!(tcx, crate, PanicRuntime);
providers.is_compiler_builtins = |tcx, LocalCrate| find_attr!(tcx, crate, CompilerBuiltins);
providers.has_panic_handler = |tcx, LocalCrate| {
// We want to check if the panic handler was defined in this crate
tcx.lang_items().panic_impl().is_some_and(|did| did.is_local())
};
providers.source_span = |tcx, def_id| tcx.untracked.source_span.get(def_id).unwrap_or(DUMMY_SP);
}