diff options
Diffstat (limited to 'compiler/rustc_infer/src/infer/canonical/instantiate.rs')
| -rw-r--r-- | compiler/rustc_infer/src/infer/canonical/instantiate.rs | 74 |
1 files changed, 18 insertions, 56 deletions
diff --git a/compiler/rustc_infer/src/infer/canonical/instantiate.rs b/compiler/rustc_infer/src/infer/canonical/instantiate.rs index cc052fbd85c..c215a9db2a0 100644 --- a/compiler/rustc_infer/src/infer/canonical/instantiate.rs +++ b/compiler/rustc_infer/src/infer/canonical/instantiate.rs @@ -11,7 +11,7 @@ use rustc_middle::ty::{ self, DelayedMap, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeSuperVisitable, TypeVisitableExt, TypeVisitor, }; -use rustc_type_ir::TypeVisitable; +use rustc_type_ir::{TypeFlags, TypeVisitable}; use crate::infer::canonical::{Canonical, CanonicalVarValues}; @@ -66,7 +66,6 @@ where value.fold_with(&mut CanonicalInstantiator { tcx, - current_index: ty::INNERMOST, var_values: var_values.var_values, cache: Default::default(), }) @@ -79,12 +78,9 @@ struct CanonicalInstantiator<'tcx> { // The values that the bound vars are are being instantiated with. var_values: ty::GenericArgsRef<'tcx>, - /// As with `BoundVarReplacer`, represents the index of a binder *just outside* - /// the ones we have visited. - current_index: ty::DebruijnIndex, - - // Instantiation is a pure function of `DebruijnIndex` and `Ty`. - cache: DelayedMap<(ty::DebruijnIndex, Ty<'tcx>), Ty<'tcx>>, + // Because we use `ty::BoundVarIndexKind::Canonical`, we can cache + // based only on the entire ty, not worrying about a `DebruijnIndex` + cache: DelayedMap<Ty<'tcx>, Ty<'tcx>>, } impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { @@ -92,29 +88,19 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { self.tcx } - fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>( - &mut self, - t: ty::Binder<'tcx, T>, - ) -> ty::Binder<'tcx, T> { - self.current_index.shift_in(1); - let t = t.super_fold_with(self); - self.current_index.shift_out(1); - t - } - fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> { match *t.kind() { - ty::Bound(debruijn, bound_ty) if debruijn == self.current_index => { + ty::Bound(ty::BoundVarIndexKind::Canonical, bound_ty) => { self.var_values[bound_ty.var.as_usize()].expect_ty() } _ => { - if !t.has_vars_bound_at_or_above(self.current_index) { + if !t.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) { t - } else if let Some(&t) = self.cache.get(&(self.current_index, t)) { + } else if let Some(&t) = self.cache.get(&t) { t } else { let res = t.super_fold_with(self); - assert!(self.cache.insert((self.current_index, t), res)); + assert!(self.cache.insert(t, res)); res } } @@ -123,7 +109,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { match r.kind() { - ty::ReBound(debruijn, br) if debruijn == self.current_index => { + ty::ReBound(ty::BoundVarIndexKind::Canonical, br) => { self.var_values[br.var.as_usize()].expect_region() } _ => r, @@ -132,7 +118,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> { match ct.kind() { - ty::ConstKind::Bound(debruijn, bound_const) if debruijn == self.current_index => { + ty::ConstKind::Bound(ty::BoundVarIndexKind::Canonical, bound_const) => { self.var_values[bound_const.var.as_usize()].expect_const() } _ => ct.super_fold_with(self), @@ -140,22 +126,14 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { } fn fold_predicate(&mut self, p: ty::Predicate<'tcx>) -> ty::Predicate<'tcx> { - if p.has_vars_bound_at_or_above(self.current_index) { p.super_fold_with(self) } else { p } + if p.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) { p.super_fold_with(self) } else { p } } fn fold_clauses(&mut self, c: ty::Clauses<'tcx>) -> ty::Clauses<'tcx> { - if !c.has_vars_bound_at_or_above(self.current_index) { + if !c.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) { return c; } - // Since instantiation is a function of `DebruijnIndex`, we don't want - // to have to cache more copies of clauses when we're inside of binders. - // Since we currently expect to only have clauses in the outermost - // debruijn index, we just fold if we're inside of a binder. - if self.current_index > ty::INNERMOST { - return c.super_fold_with(self); - } - // Our cache key is `(clauses, var_values)`, but we also don't care about // var values that aren't named in the clauses, since they can change without // affecting the output. Since `ParamEnv`s are cached first, we compute the @@ -185,45 +163,29 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for CanonicalInstantiator<'tcx> { fn highest_var_in_clauses<'tcx>(c: ty::Clauses<'tcx>) -> usize { struct HighestVarInClauses { max_var: usize, - current_index: ty::DebruijnIndex, } impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for HighestVarInClauses { - fn visit_binder<T: TypeVisitable<TyCtxt<'tcx>>>( - &mut self, - t: &ty::Binder<'tcx, T>, - ) -> Self::Result { - self.current_index.shift_in(1); - let t = t.super_visit_with(self); - self.current_index.shift_out(1); - t - } fn visit_ty(&mut self, t: Ty<'tcx>) { - if let ty::Bound(debruijn, bound_ty) = *t.kind() - && debruijn == self.current_index - { + if let ty::Bound(ty::BoundVarIndexKind::Canonical, bound_ty) = *t.kind() { self.max_var = self.max_var.max(bound_ty.var.as_usize()); - } else if t.has_vars_bound_at_or_above(self.current_index) { + } else if t.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) { t.super_visit_with(self); } } fn visit_region(&mut self, r: ty::Region<'tcx>) { - if let ty::ReBound(debruijn, bound_region) = r.kind() - && debruijn == self.current_index - { + if let ty::ReBound(ty::BoundVarIndexKind::Canonical, bound_region) = r.kind() { self.max_var = self.max_var.max(bound_region.var.as_usize()); } } fn visit_const(&mut self, ct: ty::Const<'tcx>) { - if let ty::ConstKind::Bound(debruijn, bound_const) = ct.kind() - && debruijn == self.current_index - { + if let ty::ConstKind::Bound(ty::BoundVarIndexKind::Canonical, bound_const) = ct.kind() { self.max_var = self.max_var.max(bound_const.var.as_usize()); - } else if ct.has_vars_bound_at_or_above(self.current_index) { + } else if ct.has_type_flags(TypeFlags::HAS_CANONICAL_BOUND) { ct.super_visit_with(self); } } } - let mut visitor = HighestVarInClauses { max_var: 0, current_index: ty::INNERMOST }; + let mut visitor = HighestVarInClauses { max_var: 0 }; c.visit_with(&mut visitor); visitor.max_var } |