diff options
Diffstat (limited to 'compiler/rustc_infer/src/infer/outlives/verify.rs')
| -rw-r--r-- | compiler/rustc_infer/src/infer/outlives/verify.rs | 73 |
1 files changed, 27 insertions, 46 deletions
diff --git a/compiler/rustc_infer/src/infer/outlives/verify.rs b/compiler/rustc_infer/src/infer/outlives/verify.rs index f470b2eb8..94de9bc2d 100644 --- a/compiler/rustc_infer/src/infer/outlives/verify.rs +++ b/compiler/rustc_infer/src/infer/outlives/verify.rs @@ -1,11 +1,10 @@ use crate::infer::outlives::components::{compute_components_recursive, Component}; use crate::infer::outlives::env::RegionBoundPairs; use crate::infer::region_constraints::VerifyIfEq; -use crate::infer::{GenericKind, VerifyBound}; +use crate::infer::VerifyBound; use rustc_data_structures::sso::SsoHashSet; -use rustc_hir::def_id::DefId; use rustc_middle::ty::GenericArg; -use rustc_middle::ty::{self, EarlyBinder, OutlivesPredicate, SubstsRef, Ty, TyCtxt}; +use rustc_middle::ty::{self, OutlivesPredicate, Ty, TyCtxt}; use smallvec::smallvec; @@ -94,29 +93,26 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> { /// this list. pub fn approx_declared_bounds_from_env( &self, - generic: GenericKind<'tcx>, + alias_ty: ty::AliasTy<'tcx>, ) -> Vec<ty::Binder<'tcx, ty::OutlivesPredicate<Ty<'tcx>, ty::Region<'tcx>>>> { - let projection_ty = generic.to_ty(self.tcx); - let erased_projection_ty = self.tcx.erase_regions(projection_ty); - self.declared_generic_bounds_from_env_for_erased_ty(erased_projection_ty) + let erased_alias_ty = self.tcx.erase_regions(alias_ty.to_ty(self.tcx)); + self.declared_generic_bounds_from_env_for_erased_ty(erased_alias_ty) } #[instrument(level = "debug", skip(self, visited))] - pub fn projection_opaque_bounds( + pub fn alias_bound( &self, - generic: GenericKind<'tcx>, - def_id: DefId, - substs: SubstsRef<'tcx>, + alias_ty: ty::AliasTy<'tcx>, visited: &mut SsoHashSet<GenericArg<'tcx>>, ) -> VerifyBound<'tcx> { - let generic_ty = generic.to_ty(self.tcx); + let alias_ty_as_ty = alias_ty.to_ty(self.tcx); // Search the env for where clauses like `P: 'a`. - let projection_opaque_bounds = self - .approx_declared_bounds_from_env(generic) + let env_bounds = self + .approx_declared_bounds_from_env(alias_ty) .into_iter() .map(|binder| { - if let Some(ty::OutlivesPredicate(ty, r)) = binder.no_bound_vars() && ty == generic_ty { + if let Some(ty::OutlivesPredicate(ty, r)) = binder.no_bound_vars() && ty == alias_ty_as_ty { // Micro-optimize if this is an exact match (this // occurs often when there are no region variables // involved). @@ -126,19 +122,19 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> { VerifyBound::IfEq(verify_if_eq_b) } }); - // Extend with bounds that we can find from the trait. - let trait_bounds = - self.declared_region_bounds(def_id, substs).map(|r| VerifyBound::OutlivedBy(r)); + + // Extend with bounds that we can find from the definition. + let definition_bounds = + self.declared_bounds_from_definition(alias_ty).map(|r| VerifyBound::OutlivedBy(r)); // see the extensive comment in projection_must_outlive let recursive_bound = { let mut components = smallvec![]; - compute_components_recursive(self.tcx, generic_ty.into(), &mut components, visited); + compute_components_recursive(self.tcx, alias_ty_as_ty.into(), &mut components, visited); self.bound_from_components(&components, visited) }; - VerifyBound::AnyBound(projection_opaque_bounds.chain(trait_bounds).collect()) - .or(recursive_bound) + VerifyBound::AnyBound(env_bounds.chain(definition_bounds).collect()).or(recursive_bound) } fn bound_from_components( @@ -149,10 +145,8 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> { let mut bounds = components .iter() .map(|component| self.bound_from_single_component(component, visited)) - .filter(|bound| { - // Remove bounds that must hold, since they are not interesting. - !bound.must_hold() - }); + // Remove bounds that must hold, since they are not interesting. + .filter(|bound| !bound.must_hold()); match (bounds.next(), bounds.next()) { (Some(first), None) => first, @@ -170,19 +164,8 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> { match *component { Component::Region(lt) => VerifyBound::OutlivedBy(lt), Component::Param(param_ty) => self.param_bound(param_ty), - Component::Opaque(did, substs) => self.projection_opaque_bounds( - GenericKind::Opaque(did, substs), - did, - substs, - visited, - ), - Component::Projection(projection_ty) => self.projection_opaque_bounds( - GenericKind::Projection(projection_ty), - projection_ty.item_def_id, - projection_ty.substs, - visited, - ), - Component::EscapingProjection(ref components) => { + Component::Alias(alias_ty) => self.alias_bound(alias_ty, visited), + Component::EscapingAlias(ref components) => { self.bound_from_components(components, visited) } Component::UnresolvedInferenceVariable(v) => { @@ -298,20 +281,18 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> { /// /// This is for simplicity, and because we are not really smart /// enough to cope with such bounds anywhere. - pub fn declared_region_bounds( + pub fn declared_bounds_from_definition( &self, - def_id: DefId, - substs: SubstsRef<'tcx>, + alias_ty: ty::AliasTy<'tcx>, ) -> impl Iterator<Item = ty::Region<'tcx>> { let tcx = self.tcx; - let bounds = tcx.item_bounds(def_id); - trace!("{:#?}", bounds); + let bounds = tcx.item_bounds(alias_ty.def_id); + trace!("{:#?}", bounds.0); bounds - .into_iter() + .subst_iter(tcx, alias_ty.substs) .filter_map(|p| p.to_opt_type_outlives()) .filter_map(|p| p.no_bound_vars()) - .map(|b| b.1) - .map(move |r| EarlyBinder(r).subst(tcx, substs)) + .map(|OutlivesPredicate(_, r)| r) } /// Searches through a predicate list for a predicate `T: 'a`. |