Rework ty::Clause, use it more

Cargo.lock

@@ -67,9 +67,9 @@ dependencies = [
 
 [[package]]
 name = "allocator-api2"
-version = "0.2.14"
+version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4f263788a35611fba42eb41ff811c5d0360c58b97402570312a350736e2542e"
+checksum = "56fc6cf8dc8c4158eed8649f9b8b0ea1518eb62b544fe9490d66fa0b349eafe9"
 
 [[package]]
 name = "ammonia"

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -677,8 +677,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let tcx = self.infcx.tcx;
 
         // Find out if the predicates show that the type is a Fn or FnMut
-        let find_fn_kind_from_did = |(pred, _): (ty::Predicate<'tcx>, _)| {
-            if let ty::PredicateKind::Clause(ty::Clause::Trait(pred)) = pred.kind().skip_binder()
+        let find_fn_kind_from_did = |(pred, _): (ty::Clause<'tcx>, _)| {
+            if let ty::ClauseKind::Trait(pred) = pred.kind().skip_binder()
                 && pred.self_ty() == ty
             {
                 if Some(pred.def_id()) == tcx.lang_items().fn_trait() {
@@ -704,7 +704,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => tcx
                 .explicit_item_bounds(def_id)
                 .subst_iter_copied(tcx, substs)
-                .find_map(find_fn_kind_from_did),
+                .find_map(|(clause, span)| find_fn_kind_from_did((clause, span))),
             ty::Closure(_, substs) => match substs.as_closure().kind() {
                 ty::ClosureKind::Fn => Some(hir::Mutability::Not),
                 ty::ClosureKind::FnMut => Some(hir::Mutability::Mut),
@@ -775,7 +775,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let predicates: Result<Vec<_>, _> = errors
             .into_iter()
             .map(|err| match err.obligation.predicate.kind().skip_binder() {
-                PredicateKind::Clause(ty::Clause::Trait(predicate)) => {
+                PredicateKind::Clause(ty::ClauseKind::Trait(predicate)) => {
                     match predicate.self_ty().kind() {
                         ty::Param(param_ty) => Ok((
                             generics.type_param(param_ty, tcx),

compiler/rustc_borrowck/src/diagnostics/region_name.rs

@@ -928,7 +928,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
 
     fn any_param_predicate_mentions(
         &self,
-        predicates: &[ty::Predicate<'tcx>],
+        predicates: &[ty::Clause<'tcx>],
         ty: Ty<'tcx>,
         region: ty::EarlyBoundRegion,
     ) -> bool {
@@ -939,8 +939,8 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             {
                 predicates.iter().any(|pred| {
                     match pred.kind().skip_binder() {
-                        ty::PredicateKind::Clause(ty::Clause::Trait(data)) if data.self_ty() == ty => {}
-                        ty::PredicateKind::Clause(ty::Clause::Projection(data)) if data.projection_ty.self_ty() == ty => {}
+                        ty::ClauseKind::Trait(data) if data.self_ty() == ty => {}
+                        ty::ClauseKind::Projection(data) if data.projection_ty.self_ty() == ty => {}
                         _ => return false,
                     }
                     tcx.any_free_region_meets(pred, |r| {

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -330,8 +330,9 @@ fn check_opaque_type_well_formed<'tcx>(
     // Require the hidden type to be well-formed with only the generics of the opaque type.
     // Defining use functions may have more bounds than the opaque type, which is ok, as long as the
     // hidden type is well formed even without those bounds.
-    let predicate =
-        ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::WellFormed(definition_ty.into())));
+    let predicate = ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(
+        definition_ty.into(),
+    )));
     ocx.register_obligation(Obligation::misc(tcx, definition_span, def_id, param_env, predicate));
 
     // Check that all obligations are satisfied by the implementation's

compiler/rustc_borrowck/src/type_check/canonical.rs

@@ -89,11 +89,13 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         category: ConstraintCategory<'tcx>,
     ) {
         self.prove_predicate(
-            ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::Trait(ty::TraitPredicate {
-                trait_ref,
-                constness: ty::BoundConstness::NotConst,
-                polarity: ty::ImplPolarity::Positive,
-            }))),
+            ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::Trait(
+                ty::TraitPredicate {
+                    trait_ref,
+                    constness: ty::BoundConstness::NotConst,
+                    polarity: ty::ImplPolarity::Positive,
+                },
+            ))),
             locations,
             category,
         );

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -1420,7 +1420,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 // See #91068 for an example.
                 self.prove_predicates(
                     sig.inputs_and_output.iter().map(|ty| {
-                        ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::WellFormed(
+                        ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(
                             ty.into(),
                         )))
                     }),
@@ -1852,7 +1852,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
                 let array_ty = rvalue.ty(body.local_decls(), tcx);
                 self.prove_predicate(
-                    ty::PredicateKind::Clause(ty::Clause::WellFormed(array_ty.into())),
+                    ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(array_ty.into())),
                     Locations::Single(location),
                     ConstraintCategory::Boring,
                 );
@@ -2025,10 +2025,11 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                             ConstraintCategory::Cast,
                         );
 
-                        let outlives_predicate =
-                            tcx.mk_predicate(Binder::dummy(ty::PredicateKind::Clause(
-                                ty::Clause::TypeOutlives(ty::OutlivesPredicate(self_ty, *region)),
-                            )));
+                        let outlives_predicate = tcx.mk_predicate(Binder::dummy(
+                            ty::PredicateKind::Clause(ty::ClauseKind::TypeOutlives(
+                                ty::OutlivesPredicate(self_ty, *region),
+                            )),
+                        ));
                         self.prove_predicate(
                             outlives_predicate,
                             location.to_locations(),

compiler/rustc_hir_analysis/src/astconv/errors.rs

@@ -343,7 +343,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         let format_pred = |pred: ty::Predicate<'tcx>| {
             let bound_predicate = pred.kind();
             match bound_predicate.skip_binder() {
-                ty::PredicateKind::Clause(ty::Clause::Projection(pred)) => {
+                ty::PredicateKind::Clause(ty::ClauseKind::Projection(pred)) => {
                     let pred = bound_predicate.rebind(pred);
                     // `<Foo as Iterator>::Item = String`.
                     let projection_ty = pred.skip_binder().projection_ty;
@@ -364,7 +364,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     bound_span_label(projection_ty.self_ty(), &obligation, &quiet);
                     Some((obligation, projection_ty.self_ty()))
                 }
-                ty::PredicateKind::Clause(ty::Clause::Trait(poly_trait_ref)) => {
+                ty::PredicateKind::Clause(ty::ClauseKind::Trait(poly_trait_ref)) => {
                     let p = poly_trait_ref.trait_ref;
                     let self_ty = p.self_ty();
                     let path = p.print_only_trait_path();

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -945,38 +945,29 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
         let mut trait_bounds = vec![];
         let mut projection_bounds = vec![];
-        for (clause, span) in bounds.predicates() {
-            let pred: ty::Predicate<'tcx> = clause.to_predicate(tcx);
+        for (pred, span) in bounds.clauses() {
             let bound_pred = pred.kind();
             match bound_pred.skip_binder() {
-                ty::PredicateKind::Clause(clause) => match clause {
-                    ty::Clause::Trait(trait_pred) => {
-                        assert_eq!(trait_pred.polarity, ty::ImplPolarity::Positive);
-                        trait_bounds.push((
-                            bound_pred.rebind(trait_pred.trait_ref),
-                            span,
-                            trait_pred.constness,
-                        ));
-                    }
-                    ty::Clause::Projection(proj) => {
-                        projection_bounds.push((bound_pred.rebind(proj), span));
-                    }
-                    ty::Clause::TypeOutlives(_) => {
-                        // Do nothing, we deal with regions separately
-                    }
-                    ty::Clause::RegionOutlives(_)
-                    | ty::Clause::ConstArgHasType(..)
-                    | ty::Clause::WellFormed(_)
-                    | ty::Clause::ConstEvaluatable(_) => bug!(),
-                },
-                ty::PredicateKind::AliasRelate(..)
-                | ty::PredicateKind::ObjectSafe(_)
-                | ty::PredicateKind::ClosureKind(_, _, _)
-                | ty::PredicateKind::Subtype(_)
-                | ty::PredicateKind::Coerce(_)
-                | ty::PredicateKind::ConstEquate(_, _)
-                | ty::PredicateKind::TypeWellFormedFromEnv(_)
-                | ty::PredicateKind::Ambiguous => bug!(),
+                ty::ClauseKind::Trait(trait_pred) => {
+                    assert_eq!(trait_pred.polarity, ty::ImplPolarity::Positive);
+                    trait_bounds.push((
+                        bound_pred.rebind(trait_pred.trait_ref),
+                        span,
+                        trait_pred.constness,
+                    ));
+                }
+                ty::ClauseKind::Projection(proj) => {
+                    projection_bounds.push((bound_pred.rebind(proj), span));
+                }
+                ty::ClauseKind::TypeOutlives(_) => {
+                    // Do nothing, we deal with regions separately
+                }
+                ty::ClauseKind::RegionOutlives(_)
+                | ty::ClauseKind::ConstArgHasType(..)
+                | ty::ClauseKind::WellFormed(_)
+                | ty::ClauseKind::ConstEvaluatable(_) => {
+                    bug!()
+                }
             }
         }
 
@@ -1064,7 +1055,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
                 let bound_predicate = pred.kind();
                 match bound_predicate.skip_binder() {
-                    ty::PredicateKind::Clause(ty::Clause::Trait(pred)) => {
+                    ty::PredicateKind::Clause(ty::ClauseKind::Trait(pred)) => {
                         let pred = bound_predicate.rebind(pred);
                         associated_types.entry(span).or_default().extend(
                             tcx.associated_items(pred.def_id())
@@ -1074,7 +1065,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                                 .map(|item| item.def_id),
                         );
                     }
-                    ty::PredicateKind::Clause(ty::Clause::Projection(pred)) => {
+                    ty::PredicateKind::Clause(ty::ClauseKind::Projection(pred)) => {
                         let pred = bound_predicate.rebind(pred);
                         // A `Self` within the original bound will be substituted with a
                         // `trait_object_dummy_self`, so check for that.
@@ -1423,9 +1414,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             || {
                 traits::transitive_bounds_that_define_assoc_item(
                     tcx,
-                    predicates.iter().filter_map(|(p, _)| {
-                        Some(p.to_opt_poly_trait_pred()?.map_bound(|t| t.trait_ref))
-                    }),
+                    predicates
+                        .iter()
+                        .filter_map(|(p, _)| Some(p.as_trait_clause()?.map_bound(|t| t.trait_ref))),
                     assoc_name,
                 )
             },

compiler/rustc_hir_analysis/src/bounds.rs

@@ -2,7 +2,6 @@
 //! `ty` form from the HIR.
 
 use rustc_hir::LangItem;
-use rustc_middle::ty::Binder;
 use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt};
 use rustc_span::Span;
 
@@ -24,58 +23,58 @@ use rustc_span::Span;
 /// include the self type (e.g., `trait_bounds`) but in others we do not
 #[derive(Default, PartialEq, Eq, Clone, Debug)]
 pub struct Bounds<'tcx> {
-    pub predicates: Vec<(Binder<'tcx, ty::Clause<'tcx>>, Span)>,
+    pub predicates: Vec<(ty::Clause<'tcx>, Span)>,
 }
 
 impl<'tcx> Bounds<'tcx> {
     pub fn push_region_bound(
         &mut self,
-        _tcx: TyCtxt<'tcx>,
+        tcx: TyCtxt<'tcx>,
         region: ty::PolyTypeOutlivesPredicate<'tcx>,
         span: Span,
     ) {
-        self.predicates.push((region.map_bound(|p| ty::Clause::TypeOutlives(p)), span));
+        self.predicates
+            .push((region.map_bound(|p| ty::ClauseKind::TypeOutlives(p)).to_predicate(tcx), span));
     }
 
     pub fn push_trait_bound(
         &mut self,
-        _tcx: TyCtxt<'tcx>,
+        tcx: TyCtxt<'tcx>,
         trait_ref: ty::PolyTraitRef<'tcx>,
         span: Span,
         constness: ty::BoundConstness,
         polarity: ty::ImplPolarity,
     ) {
         self.predicates.push((
-            trait_ref.map_bound(|trait_ref| {
-                ty::Clause::Trait(ty::TraitPredicate { trait_ref, constness, polarity })
-            }),
+            trait_ref
+                .map_bound(|trait_ref| {
+                    ty::ClauseKind::Trait(ty::TraitPredicate { trait_ref, constness, polarity })
+                })
+                .to_predicate(tcx),
             span,
         ));
     }
 
     pub fn push_projection_bound(
         &mut self,
-        _tcx: TyCtxt<'tcx>,
+        tcx: TyCtxt<'tcx>,
         projection: ty::PolyProjectionPredicate<'tcx>,
         span: Span,
     ) {
-        self.predicates.push((projection.map_bound(|proj| ty::Clause::Projection(proj)), span));
+        self.predicates.push((
+            projection.map_bound(|proj| ty::ClauseKind::Projection(proj)).to_predicate(tcx),
+            span,
+        ));
     }
 
     pub fn push_sized(&mut self, tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, span: Span) {
         let sized_def_id = tcx.require_lang_item(LangItem::Sized, Some(span));
         let trait_ref = ty::TraitRef::new(tcx, sized_def_id, [ty]);
         // Preferable to put this obligation first, since we report better errors for sized ambiguity.
-        self.predicates.insert(
-            0,
-            (
-                ty::Binder::dummy(ty::Clause::Trait(trait_ref.without_const().to_predicate(tcx))),
-                span,
-            ),
-        );
+        self.predicates.insert(0, (trait_ref.to_predicate(tcx), span));
     }
 
-    pub fn predicates(&self) -> impl Iterator<Item = (Binder<'tcx, ty::Clause<'tcx>>, Span)> + '_ {
+    pub fn clauses(&self) -> impl Iterator<Item = (ty::Clause<'tcx>, Span)> + '_ {
         self.predicates.iter().cloned()
     }
 }

compiler/rustc_hir_analysis/src/check/check.rs

@@ -440,7 +440,7 @@ fn check_opaque_meets_bounds<'tcx>(
     // Defining use functions may have more bounds than the opaque type, which is ok, as long as the
     // hidden type is well formed even without those bounds.
     let predicate =
-        ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::WellFormed(hidden_ty.into())));
+        ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(hidden_ty.into())));
     ocx.register_obligation(Obligation::new(tcx, misc_cause, param_env, predicate));
 
     // Check that all obligations are satisfied by the implementation's

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -220,7 +220,7 @@ fn compare_method_predicate_entailment<'tcx>(
     // the new hybrid bounds we computed.
     let normalize_cause = traits::ObligationCause::misc(impl_m_span, impl_m_def_id);
     let param_env = ty::ParamEnv::new(
-        tcx.mk_predicates(&hybrid_preds.predicates),
+        tcx.mk_clauses(&hybrid_preds.predicates),
         Reveal::UserFacing,
         hir::Constness::NotConst,
     );
@@ -321,7 +321,7 @@ fn compare_method_predicate_entailment<'tcx>(
             infcx.tcx,
             ObligationCause::dummy(),
             param_env,
-            ty::Binder::dummy(ty::PredicateKind::Clause(ty::Clause::WellFormed(
+            ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(
                 unnormalized_impl_fty.into(),
             ))),
         ));
@@ -1835,7 +1835,7 @@ fn compare_type_predicate_entailment<'tcx>(
     let impl_ty_span = tcx.def_span(impl_ty_def_id);
     let normalize_cause = traits::ObligationCause::misc(impl_ty_span, impl_ty_def_id);
     let param_env = ty::ParamEnv::new(
-        tcx.mk_predicates(&hybrid_preds.predicates),
+        tcx.mk_clauses(&hybrid_preds.predicates),
         Reveal::UserFacing,
         hir::Constness::NotConst,
     );
@@ -2011,7 +2011,7 @@ pub(super) fn check_type_bounds<'tcx>(
                 .to_predicate(tcx),
             ),
         };
-        ty::ParamEnv::new(tcx.mk_predicates(&predicates), Reveal::UserFacing, param_env.constness())
+        ty::ParamEnv::new(tcx.mk_clauses(&predicates), Reveal::UserFacing, param_env.constness())
     };
     debug!(?normalize_param_env);
 

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -296,15 +296,15 @@ fn default_body_is_unstable(
 /// Re-sugar `ty::GenericPredicates` in a way suitable to be used in structured suggestions.
 fn bounds_from_generic_predicates<'tcx>(
     tcx: TyCtxt<'tcx>,
-    predicates: impl IntoIterator<Item = (ty::Predicate<'tcx>, Span)>,
+    predicates: impl IntoIterator<Item = (ty::Clause<'tcx>, Span)>,
 ) -> (String, String) {
     let mut types: FxHashMap<Ty<'tcx>, Vec<DefId>> = FxHashMap::default();
     let mut projections = vec![];
     for (predicate, _) in predicates {
         debug!("predicate {:?}", predicate);
         let bound_predicate = predicate.kind();
         match bound_predicate.skip_binder() {
-            ty::PredicateKind::Clause(ty::Clause::Trait(trait_predicate)) => {
+            ty::ClauseKind::Trait(trait_predicate) => {
                 let entry = types.entry(trait_predicate.self_ty()).or_default();
                 let def_id = trait_predicate.def_id();
                 if Some(def_id) != tcx.lang_items().sized_trait() {
@@ -313,7 +313,7 @@ fn bounds_from_generic_predicates<'tcx>(
                     entry.push(trait_predicate.def_id());
                 }
             }
-            ty::PredicateKind::Clause(ty::Clause::Projection(projection_pred)) => {
+            ty::ClauseKind::Projection(projection_pred) => {
                 projections.push(bound_predicate.rebind(projection_pred));
             }
             _ => {}
@@ -362,7 +362,7 @@ fn fn_sig_suggestion<'tcx>(
     tcx: TyCtxt<'tcx>,
     sig: ty::FnSig<'tcx>,
     ident: Ident,
-    predicates: impl IntoIterator<Item = (ty::Predicate<'tcx>, Span)>,
+    predicates: impl IntoIterator<Item = (ty::Clause<'tcx>, Span)>,
     assoc: ty::AssocItem,
 ) -> String {
     let args = sig