diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/fold.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/fold.rs | 44 |
1 files changed, 21 insertions, 23 deletions
diff --git a/compiler/rustc_middle/src/ty/fold.rs b/compiler/rustc_middle/src/ty/fold.rs index 00529a1e0..3e64f9a2a 100644 --- a/compiler/rustc_middle/src/ty/fold.rs +++ b/compiler/rustc_middle/src/ty/fold.rs @@ -68,12 +68,10 @@ impl<'tcx> TyCtxt<'tcx> { /// Folds over the substructure of a type, visiting its component /// types and all regions that occur *free* within it. /// -/// That is, `Ty` can contain function or method types that bind -/// regions at the call site (`ReLateBound`), and occurrences of -/// regions (aka "lifetimes") that are bound within a type are not -/// visited by this folder; only regions that occur free will be +/// That is, function pointer types and trait object can introduce +/// new bound regions which are not visited by this visitors as +/// they are not free; only regions that occur free will be /// visited by `fld_r`. - pub struct RegionFolder<'a, 'tcx> { tcx: TyCtxt<'tcx>, @@ -117,7 +115,7 @@ impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for RegionFolder<'a, 'tcx> { #[instrument(skip(self), level = "debug", ret)] fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { match *r { - ty::ReLateBound(debruijn, _) if debruijn < self.current_index => { + ty::ReBound(debruijn, _) if debruijn < self.current_index => { debug!(?self.current_index, "skipped bound region"); r } @@ -205,15 +203,15 @@ where fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { match *r { - ty::ReLateBound(debruijn, br) if debruijn == self.current_index => { + ty::ReBound(debruijn, br) if debruijn == self.current_index => { let region = self.delegate.replace_region(br); - if let ty::ReLateBound(debruijn1, br) = *region { - // If the callback returns a late-bound region, + if let ty::ReBound(debruijn1, br) = *region { + // If the callback returns a bound region, // that region should always use the INNERMOST // debruijn index. Then we adjust it to the // correct depth. assert_eq!(debruijn1, ty::INNERMOST); - ty::Region::new_late_bound(self.tcx, debruijn, br) + ty::Region::new_bound(self.tcx, debruijn, br) } else { region } @@ -252,7 +250,7 @@ impl<'tcx> TyCtxt<'tcx> { /// /// This method only replaces late bound regions. Any types or /// constants bound by `value` will cause an ICE. - pub fn replace_late_bound_regions<T, F>( + pub fn instantiate_bound_regions<T, F>( self, value: Binder<'tcx, T>, mut fld_r: F, @@ -263,11 +261,11 @@ impl<'tcx> TyCtxt<'tcx> { { let mut region_map = BTreeMap::new(); let real_fld_r = |br: ty::BoundRegion| *region_map.entry(br).or_insert_with(|| fld_r(br)); - let value = self.replace_late_bound_regions_uncached(value, real_fld_r); + let value = self.instantiate_bound_regions_uncached(value, real_fld_r); (value, region_map) } - pub fn replace_late_bound_regions_uncached<T, F>( + pub fn instantiate_bound_regions_uncached<T, F>( self, value: Binder<'tcx, T>, mut replace_regions: F, @@ -327,8 +325,8 @@ impl<'tcx> TyCtxt<'tcx> { where T: TypeFoldable<TyCtxt<'tcx>>, { - self.replace_late_bound_regions_uncached(value, |br| { - ty::Region::new_free(self, all_outlive_scope, br.kind) + self.instantiate_bound_regions_uncached(value, |br| { + ty::Region::new_late_param(self, all_outlive_scope, br.kind) }) } @@ -341,7 +339,7 @@ impl<'tcx> TyCtxt<'tcx> { value, FnMutDelegate { regions: &mut |r: ty::BoundRegion| { - ty::Region::new_late_bound( + ty::Region::new_bound( self, ty::INNERMOST, ty::BoundRegion { var: shift_bv(r.var), kind: r.kind }, @@ -363,11 +361,11 @@ impl<'tcx> TyCtxt<'tcx> { /// Replaces any late-bound regions bound in `value` with `'erased`. Useful in codegen but also /// method lookup and a few other places where precise region relationships are not required. - pub fn erase_late_bound_regions<T>(self, value: Binder<'tcx, T>) -> T + pub fn instantiate_bound_regions_with_erased<T>(self, value: Binder<'tcx, T>) -> T where T: TypeFoldable<TyCtxt<'tcx>>, { - self.replace_late_bound_regions(value, |_| self.lifetimes.re_erased).0 + self.instantiate_bound_regions(value, |_| self.lifetimes.re_erased).0 } /// Anonymize all bound variables in `value`, this is mostly used to improve caching. @@ -388,7 +386,7 @@ impl<'tcx> TyCtxt<'tcx> { .or_insert_with(|| ty::BoundVariableKind::Region(ty::BrAnon)) .expect_region(); let br = ty::BoundRegion { var, kind }; - ty::Region::new_late_bound(self.tcx, ty::INNERMOST, br) + ty::Region::new_bound(self.tcx, ty::INNERMOST, br) } fn replace_ty(&mut self, bt: ty::BoundTy) -> Ty<'tcx> { let entry = self.map.entry(bt.var); @@ -454,9 +452,9 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for Shifter<'tcx> { fn fold_region(&mut self, r: ty::Region<'tcx>) -> ty::Region<'tcx> { match *r { - ty::ReLateBound(debruijn, br) if debruijn >= self.current_index => { + ty::ReBound(debruijn, br) if debruijn >= self.current_index => { let debruijn = debruijn.shifted_in(self.amount); - ty::Region::new_late_bound(self.tcx, debruijn, br) + ty::Region::new_bound(self.tcx, debruijn, br) } _ => r, } @@ -496,8 +494,8 @@ pub fn shift_region<'tcx>( amount: u32, ) -> ty::Region<'tcx> { match *region { - ty::ReLateBound(debruijn, br) if amount > 0 => { - ty::Region::new_late_bound(tcx, debruijn.shifted_in(amount), br) + ty::ReBound(debruijn, br) if amount > 0 => { + ty::Region::new_bound(tcx, debruijn.shifted_in(amount), br) } _ => region, } |