diff options
Diffstat (limited to '')
-rw-r--r-- | compiler/rustc_borrowck/src/region_infer/mod.rs | 175 |
1 files changed, 24 insertions, 151 deletions
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs index 8b63294fb..90e2b6b69 100644 --- a/compiler/rustc_borrowck/src/region_infer/mod.rs +++ b/compiler/rustc_borrowck/src/region_infer/mod.rs @@ -6,10 +6,9 @@ use rustc_data_structures::frozen::Frozen; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_data_structures::graph::scc::Sccs; use rustc_errors::Diagnostic; -use rustc_hir::def_id::{DefId, CRATE_DEF_ID}; +use rustc_hir::def_id::CRATE_DEF_ID; use rustc_hir::CRATE_HIR_ID; use rustc_index::vec::IndexVec; -use rustc_infer::infer::canonical::QueryOutlivesConstraint; use rustc_infer::infer::outlives::test_type_match; use rustc_infer::infer::region_constraints::{GenericKind, VarInfos, VerifyBound, VerifyIfEq}; use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin, RegionVariableOrigin}; @@ -19,9 +18,7 @@ use rustc_middle::mir::{ }; use rustc_middle::traits::ObligationCause; use rustc_middle::traits::ObligationCauseCode; -use rustc_middle::ty::{ - self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable, -}; +use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable}; use rustc_span::Span; use crate::{ @@ -89,10 +86,6 @@ pub struct RegionInferenceContext<'tcx> { /// `member_region_scc`. member_constraints_applied: Vec<AppliedMemberConstraint>, - /// Map closure bounds to a `Span` that should be used for error reporting. - closure_bounds_mapping: - FxHashMap<Location, FxHashMap<(RegionVid, RegionVid), (ConstraintCategory<'tcx>, Span)>>, - /// Map universe indexes to information on why we created it. universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>, @@ -135,6 +128,7 @@ pub struct RegionInferenceContext<'tcx> { /// adds a new lower bound to the SCC it is analyzing: so you wind up /// with `'R: 'O` where `'R` is the pick-region and `'O` is the /// minimal viable option. +#[derive(Debug)] pub(crate) struct AppliedMemberConstraint { /// The SCC that was affected. (The "member region".) /// @@ -221,8 +215,8 @@ pub struct TypeTest<'tcx> { /// The region `'x` that the type must outlive. pub lower_bound: RegionVid, - /// Where did this constraint arise and why? - pub locations: Locations, + /// The span to blame. + pub span: Span, /// A test which, if met by the region `'x`, proves that this type /// constraint is satisfied. @@ -265,10 +259,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>, outlives_constraints: OutlivesConstraintSet<'tcx>, member_constraints_in: MemberConstraintSet<'tcx, RegionVid>, - closure_bounds_mapping: FxHashMap< - Location, - FxHashMap<(RegionVid, RegionVid), (ConstraintCategory<'tcx>, Span)>, - >, universe_causes: FxHashMap<ty::UniverseIndex, UniverseInfo<'tcx>>, type_tests: Vec<TypeTest<'tcx>>, liveness_constraints: LivenessValues<RegionVid>, @@ -310,7 +300,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { rev_scc_graph: None, member_constraints, member_constraints_applied: Vec::new(), - closure_bounds_mapping, universe_causes, scc_universes, scc_representatives, @@ -882,13 +871,13 @@ impl<'tcx> RegionInferenceContext<'tcx> { if deduplicate_errors.insert(( erased_generic_kind, type_test.lower_bound, - type_test.locations, + type_test.span, )) { debug!( "check_type_test: reporting error for erased_generic_kind={:?}, \ lower_bound_region={:?}, \ - type_test.locations={:?}", - erased_generic_kind, type_test.lower_bound, type_test.locations, + type_test.span={:?}", + erased_generic_kind, type_test.lower_bound, type_test.span, ); errors_buffer.push(RegionErrorKind::TypeTestError { type_test: type_test.clone() }); @@ -931,7 +920,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { ) -> bool { let tcx = infcx.tcx; - let TypeTest { generic_kind, lower_bound, locations, verify_bound: _ } = type_test; + let TypeTest { generic_kind, lower_bound, span: _, verify_bound: _ } = type_test; let generic_ty = generic_kind.to_ty(tcx); let Some(subject) = self.try_promote_type_test_subject(infcx, generic_ty) else { @@ -959,7 +948,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { propagated_outlives_requirements.push(ClosureOutlivesRequirement { subject, outlived_free_region: static_r, - blame_span: locations.span(body), + blame_span: type_test.span, category: ConstraintCategory::Boring, }); @@ -1011,7 +1000,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { let requirement = ClosureOutlivesRequirement { subject, outlived_free_region: upper_bound, - blame_span: locations.span(body), + blame_span: type_test.span, category: ConstraintCategory::Boring, }; debug!("try_promote_type_test: pushing {:#?}", requirement); @@ -1716,6 +1705,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { }); } + #[instrument(level = "debug", skip(self, infcx, errors_buffer))] fn check_member_constraints( &self, infcx: &InferCtxt<'tcx>, @@ -1723,22 +1713,21 @@ impl<'tcx> RegionInferenceContext<'tcx> { ) { let member_constraints = self.member_constraints.clone(); for m_c_i in member_constraints.all_indices() { - debug!("check_member_constraint(m_c_i={:?})", m_c_i); + debug!(?m_c_i); let m_c = &member_constraints[m_c_i]; let member_region_vid = m_c.member_region_vid; debug!( - "check_member_constraint: member_region_vid={:?} with value {}", - member_region_vid, - self.region_value_str(member_region_vid), + ?member_region_vid, + value = ?self.region_value_str(member_region_vid), ); let choice_regions = member_constraints.choice_regions(m_c_i); - debug!("check_member_constraint: choice_regions={:?}", choice_regions); + debug!(?choice_regions); // Did the member region wind up equal to any of the option regions? if let Some(o) = choice_regions.iter().find(|&&o_r| self.eval_equal(o_r, m_c.member_region_vid)) { - debug!("check_member_constraint: evaluated as equal to {:?}", o); + debug!("evaluated as equal to {:?}", o); continue; } @@ -1804,18 +1793,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { } } - pub(crate) fn retrieve_closure_constraint_info( - &self, - constraint: OutlivesConstraint<'tcx>, - ) -> Option<(ConstraintCategory<'tcx>, Span)> { - match constraint.locations { - Locations::All(_) => None, - Locations::Single(loc) => { - self.closure_bounds_mapping[&loc].get(&(constraint.sup, constraint.sub)).copied() - } - } - } - /// Finds a good `ObligationCause` to blame for the fact that `fr1` outlives `fr2`. pub(crate) fn find_outlives_blame_span( &self, @@ -1921,6 +1898,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { span: p_c.definition_span, category: ConstraintCategory::OpaqueType, variance_info: ty::VarianceDiagInfo::default(), + from_closure: false, }; handle_constraint(constraint); } @@ -2066,31 +2044,12 @@ impl<'tcx> RegionInferenceContext<'tcx> { // Classify each of the constraints along the path. let mut categorized_path: Vec<BlameConstraint<'tcx>> = path .iter() - .map(|constraint| { - let (category, span, from_closure, cause_code) = - if constraint.category == ConstraintCategory::ClosureBounds { - if let Some((category, span)) = - self.retrieve_closure_constraint_info(*constraint) - { - (category, span, true, ObligationCauseCode::MiscObligation) - } else { - ( - constraint.category, - constraint.span, - false, - ObligationCauseCode::MiscObligation, - ) - } - } else { - (constraint.category, constraint.span, false, cause_code.clone()) - }; - BlameConstraint { - category, - from_closure, - cause: ObligationCause::new(span, CRATE_HIR_ID, cause_code), - variance_info: constraint.variance_info, - outlives_constraint: *constraint, - } + .map(|constraint| BlameConstraint { + category: constraint.category, + from_closure: constraint.from_closure, + cause: ObligationCause::new(constraint.span, CRATE_HIR_ID, cause_code.clone()), + variance_info: constraint.variance_info, + outlives_constraint: *constraint, }) .collect(); debug!("categorized_path={:#?}", categorized_path); @@ -2274,92 +2233,6 @@ impl<'tcx> RegionDefinition<'tcx> { } } -pub trait ClosureRegionRequirementsExt<'tcx> { - fn apply_requirements( - &self, - tcx: TyCtxt<'tcx>, - closure_def_id: DefId, - closure_substs: SubstsRef<'tcx>, - ) -> Vec<QueryOutlivesConstraint<'tcx>>; -} - -impl<'tcx> ClosureRegionRequirementsExt<'tcx> for ClosureRegionRequirements<'tcx> { - /// Given an instance T of the closure type, this method - /// instantiates the "extra" requirements that we computed for the - /// closure into the inference context. This has the effect of - /// adding new outlives obligations to existing variables. - /// - /// As described on `ClosureRegionRequirements`, the extra - /// requirements are expressed in terms of regionvids that index - /// into the free regions that appear on the closure type. So, to - /// do this, we first copy those regions out from the type T into - /// a vector. Then we can just index into that vector to extract - /// out the corresponding region from T and apply the - /// requirements. - fn apply_requirements( - &self, - tcx: TyCtxt<'tcx>, - closure_def_id: DefId, - closure_substs: SubstsRef<'tcx>, - ) -> Vec<QueryOutlivesConstraint<'tcx>> { - debug!( - "apply_requirements(closure_def_id={:?}, closure_substs={:?})", - closure_def_id, closure_substs - ); - - // Extract the values of the free regions in `closure_substs` - // into a vector. These are the regions that we will be - // relating to one another. - let closure_mapping = &UniversalRegions::closure_mapping( - tcx, - closure_substs, - self.num_external_vids, - tcx.typeck_root_def_id(closure_def_id), - ); - debug!("apply_requirements: closure_mapping={:?}", closure_mapping); - - // Create the predicates. - self.outlives_requirements - .iter() - .map(|outlives_requirement| { - let outlived_region = closure_mapping[outlives_requirement.outlived_free_region]; - - match outlives_requirement.subject { - ClosureOutlivesSubject::Region(region) => { - let region = closure_mapping[region]; - debug!( - "apply_requirements: region={:?} \ - outlived_region={:?} \ - outlives_requirement={:?}", - region, outlived_region, outlives_requirement, - ); - ( - ty::Binder::dummy(ty::OutlivesPredicate( - region.into(), - outlived_region, - )), - ConstraintCategory::BoringNoLocation, - ) - } - - ClosureOutlivesSubject::Ty(ty) => { - debug!( - "apply_requirements: ty={:?} \ - outlived_region={:?} \ - outlives_requirement={:?}", - ty, outlived_region, outlives_requirement, - ); - ( - ty::Binder::dummy(ty::OutlivesPredicate(ty.into(), outlived_region)), - ConstraintCategory::BoringNoLocation, - ) - } - } - }) - .collect() - } -} - #[derive(Clone, Debug)] pub struct BlameConstraint<'tcx> { pub category: ConstraintCategory<'tcx>, |