FnCtxt normalization stuff

15 files changed, 41 insertions, 67 deletions

diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs
index 5f06db4038f..22ea83a13f0 100644
--- a/compiler/rustc_hir_analysis/src/astconv/mod.rs
+++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs
@@ -109,6 +109,9 @@ pub trait AstConv<'tcx> {
     ) -> Ty<'tcx>;
 
     /// Normalize an associated type coming from the user.
+    /// 
+    /// This should only be used by astconv. Use `FnCtxt::normalize`
+    /// or `ObligationCtxt::normalize` in downstream crates.
     fn normalize_ty(&self, span: Span, ty: Ty<'tcx>) -> Ty<'tcx>;
 
     /// Invoked when we encounter an error from some prior pass
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
index 8171a2ab270..894c0ba3415 100644
--- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs
+++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -53,6 +53,8 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> {
         self.ocx.infcx.tcx
     }
 
+    // Convenience function to normalize during wfcheck. This performs
+    // `ObligationCtxt::normalize`, but provides a nice `ObligationCauseCode`.
     fn normalize<T>(&self, span: Span, loc: Option<WellFormedLoc>, value: T) -> T
     where
         T: TypeFoldable<'tcx>,
diff --git a/compiler/rustc_hir_typeck/src/callee.rs b/compiler/rustc_hir_typeck/src/callee.rs
index e50d249849f..b09ddf80e2a 100644
--- a/compiler/rustc_hir_typeck/src/callee.rs
+++ b/compiler/rustc_hir_typeck/src/callee.rs
@@ -448,7 +448,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // previously appeared within a `Binder<>` and hence would not
         // have been normalized before.
         let fn_sig = self.replace_bound_vars_with_fresh_vars(call_expr.span, infer::FnCall, fn_sig);
-        let fn_sig = self.normalize_associated_types_in(call_expr.span, fn_sig);
+        let fn_sig = self.normalize(call_expr.span, fn_sig);
 
         // Call the generic checker.
         let expected_arg_tys = self.expected_inputs_for_expected_output(
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs
index 732b4bec58e..2a9679eed04 100644
--- a/compiler/rustc_hir_typeck/src/cast.rs
+++ b/compiler/rustc_hir_typeck/src/cast.rs
@@ -752,7 +752,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                 match *self.expr_ty.kind() {
                     ty::FnDef(..) => {
                         // Attempt a coercion to a fn pointer type.
-                        let f = fcx.normalize_associated_types_in(
+                        let f = fcx.normalize(
                             self.expr_span,
                             self.expr_ty.fn_sig(fcx.tcx),
                         );
diff --git a/compiler/rustc_hir_typeck/src/closure.rs b/compiler/rustc_hir_typeck/src/closure.rs
index e584d413c41..33c87768ec1 100644
--- a/compiler/rustc_hir_typeck/src/closure.rs
+++ b/compiler/rustc_hir_typeck/src/closure.rs
@@ -214,7 +214,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             if expected_sig.is_none()
                 && let ty::PredicateKind::Clause(ty::Clause::Projection(proj_predicate)) = bound_predicate.skip_binder()
             {
-                expected_sig = self.normalize_associated_types_in(
+                expected_sig = self.normalize(
                     obligation.cause.span,
                     self.deduce_sig_from_projection(
                     Some(obligation.cause.span),
@@ -623,7 +623,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         );
         // Astconv can't normalize inputs or outputs with escaping bound vars,
         // so normalize them here, after we've wrapped them in a binder.
-        let result = self.normalize_associated_types_in(self.tcx.hir().span(hir_id), result);
+        let result = self.normalize(self.tcx.hir().span(hir_id), result);
 
         let c_result = self.inh.infcx.canonicalize_response(result);
         self.typeck_results.borrow_mut().user_provided_sigs.insert(expr_def_id, c_result);
@@ -797,10 +797,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> ClosureSignatures<'tcx> {
         let liberated_sig =
             self.tcx().liberate_late_bound_regions(expr_def_id.to_def_id(), bound_sig);
-        let liberated_sig = self.inh.normalize_associated_types_in(
+        let liberated_sig = self.normalize(
             body.value.span,
-            self.tcx.hir().local_def_id_to_hir_id(expr_def_id),
-            self.param_env,
             liberated_sig,
         );
         ClosureSignatures { bound_sig, liberated_sig }
diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs
index b2d9d70fbd2..e93d95ee66d 100644
--- a/compiler/rustc_hir_typeck/src/coercion.rs
+++ b/compiler/rustc_hir_typeck/src/coercion.rs
@@ -1141,8 +1141,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 return Err(TypeError::IntrinsicCast);
             }
             // The signature must match.
-            let a_sig = self.normalize_associated_types_in(new.span, a_sig);
-            let b_sig = self.normalize_associated_types_in(new.span, b_sig);
+            let (a_sig, b_sig) = self.normalize(new.span, (a_sig, b_sig));
             let sig = self
                 .at(cause, self.param_env)
                 .trace(prev_ty, new_ty)
diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index 5166f1fd1c7..7b101fc5c66 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -1664,7 +1664,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         .fields
                         .iter()
                         .map(|f| {
-                            let fru_ty = self.normalize_associated_types_in(
+                            let fru_ty = self.normalize(
                                 expr_span,
                                 self.field_ty(base_expr.span, f, fresh_substs),
                             );
@@ -1749,7 +1749,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         .fields
                         .iter()
                         .map(|f| {
-                            self.normalize_associated_types_in(expr_span, f.ty(self.tcx, substs))
+                            self.normalize(expr_span, f.ty(self.tcx, substs))
                         })
                         .collect(),
                     _ => {
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
index 9ec85f0b142..8ce9e40cfdb 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
@@ -344,7 +344,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     {
         debug!("instantiate_type_scheme(value={:?}, substs={:?})", value, substs);
         let value = EarlyBinder(value).subst(self.tcx, substs);
-        let result = self.normalize_associated_types_in(span, value);
+        let result = self.normalize(span, value);
         debug!("instantiate_type_scheme = {:?}", result);
         result
     }
@@ -360,7 +360,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let bounds = self.tcx.predicates_of(def_id);
         let spans: Vec<Span> = bounds.predicates.iter().map(|(_, span)| *span).collect();
         let result = bounds.instantiate(self.tcx, substs);
-        let result = self.normalize_associated_types_in(span, result);
+        let result = self.normalize(span, result);
         debug!(
             "instantiate_bounds(bounds={:?}, substs={:?}) = {:?}, {:?}",
             bounds, substs, result, spans,
@@ -368,11 +368,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         (result, spans)
     }
 
-    pub(in super::super) fn normalize_associated_types_in<T>(&self, span: Span, value: T) -> T
+    pub(in super::super) fn normalize<T>(&self, span: Span, value: T) -> T
     where
         T: TypeFoldable<'tcx>,
     {
-        self.inh.normalize_associated_types_in(span, self.body_id, self.param_env, value)
+        self.register_infer_ok_obligations(
+            self.at(&self.misc(span), self.param_env).normalize(value),
+        )
     }
 
     pub(in super::super) fn normalize_associated_types_in_as_infer_ok<T>(
@@ -487,7 +489,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let span = self.tcx.def_span(anon_const.def_id);
                 let c = ty::Const::from_anon_const(self.tcx, anon_const.def_id);
                 self.register_wf_obligation(c.into(), span, ObligationCauseCode::WellFormed(None));
-                self.normalize_associated_types_in(span, c)
+                self.normalize(span, c)
             }
         }
     }
@@ -580,7 +582,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         field: &'tcx ty::FieldDef,
         substs: SubstsRef<'tcx>,
     ) -> Ty<'tcx> {
-        self.normalize_associated_types_in(span, field.ty(self.tcx, substs))
+        self.normalize(span, field.ty(self.tcx, substs))
     }
 
     pub(in super::super) fn resolve_rvalue_scopes(&self, def_id: DefId) {
@@ -1107,7 +1109,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         if let Res::Local(hid) = res {
             let ty = self.local_ty(span, hid).decl_ty;
-            let ty = self.normalize_associated_types_in(span, ty);
+            let ty = self.normalize(span, ty);
             self.write_ty(hir_id, ty);
             return (ty, res);
         }
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
index ed5f7f31764..ea141e815bf 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
@@ -288,7 +288,7 @@ impl<'a, 'tcx> AstConv<'tcx> for FnCtxt<'a, 'tcx> {
         if ty.has_escaping_bound_vars() {
             ty // FIXME: normalization and escaping regions
         } else {
-            self.normalize_associated_types_in(span, ty)
+            self.normalize(span, ty)
         }
     }
 
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
index 6c3526a71a3..10cc4e81819 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs
@@ -759,7 +759,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 debug!("suggest_missing_return_type: expected type {:?}", ty);
                 let bound_vars = self.tcx.late_bound_vars(fn_id);
                 let ty = Binder::bind_with_vars(ty, bound_vars);
-                let ty = self.normalize_associated_types_in(span, ty);
+                let ty = self.normalize(span, ty);
                 let ty = self.tcx.erase_late_bound_regions(ty);
                 if self.can_coerce(expected, ty) {
                     err.subdiagnostic(ExpectedReturnTypeLabel::Other { span, expected });
@@ -920,7 +920,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let ty = <dyn AstConv<'_>>::ast_ty_to_ty(self, ty);
             let bound_vars = self.tcx.late_bound_vars(fn_id);
             let ty = self.tcx.erase_late_bound_regions(Binder::bind_with_vars(ty, bound_vars));
-            let ty = self.normalize_associated_types_in(expr.span, ty);
+            let ty = self.normalize(expr.span, ty);
             let ty = match self.tcx.asyncness(fn_id.owner) {
                 hir::IsAsync::Async => {
                     let infcx = self.tcx.infer_ctxt().build();
diff --git a/compiler/rustc_hir_typeck/src/generator_interior/mod.rs b/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
index 4e044d39d50..3b1518ff79b 100644
--- a/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
+++ b/compiler/rustc_hir_typeck/src/generator_interior/mod.rs
@@ -235,7 +235,7 @@ pub fn resolve_interior<'a, 'tcx>(
                 counter += 1;
                 ty::BoundRegion { var, kind }
             };
-            let ty = fcx.normalize_associated_types_in(cause.span, cause.ty);
+            let ty = fcx.normalize(cause.span, cause.ty);
             let ty = fcx.tcx.fold_regions(ty, |region, current_depth| {
                 let br = match region.kind() {
                     ty::ReVar(vid) => {
diff --git a/compiler/rustc_hir_typeck/src/inherited.rs b/compiler/rustc_hir_typeck/src/inherited.rs
index 55179ff4011..e8a9e4980f6 100644
--- a/compiler/rustc_hir_typeck/src/inherited.rs
+++ b/compiler/rustc_hir_typeck/src/inherited.rs
@@ -7,13 +7,12 @@ use rustc_hir::def_id::LocalDefId;
 use rustc_hir::HirIdMap;
 use rustc_infer::infer;
 use rustc_infer::infer::{DefiningAnchor, InferCtxt, InferOk, TyCtxtInferExt};
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::def_id::LocalDefIdMap;
 use rustc_span::{self, Span};
 use rustc_trait_selection::traits::{
-    self, NormalizeExt, ObligationCause, ObligationCtxt, TraitEngine, TraitEngineExt as _,
+    self, ObligationCause, ObligationCtxt, TraitEngine, TraitEngineExt as _,
 };
 
 use std::cell::RefCell;
@@ -178,35 +177,4 @@ impl<'tcx> Inherited<'tcx> {
         self.register_predicates(infer_ok.obligations);
         infer_ok.value
     }
-
-    pub(super) fn normalize_associated_types_in<T>(
-        &self,
-        span: Span,
-        body_id: hir::HirId,
-        param_env: ty::ParamEnv<'tcx>,
-        value: T,
-    ) -> T
-    where
-        T: TypeFoldable<'tcx>,
-    {
-        self.normalize_associated_types_in_with_cause(
-            ObligationCause::misc(span, body_id),
-            param_env,
-            value,
-        )
-    }
-
-    pub(super) fn normalize_associated_types_in_with_cause<T>(
-        &self,
-        cause: ObligationCause<'tcx>,
-        param_env: ty::ParamEnv<'tcx>,
-        value: T,
-    ) -> T
-    where
-        T: TypeFoldable<'tcx>,
-    {
-        let ok = self.at(&cause, param_env).normalize(value);
-        debug!(?ok);
-        self.register_infer_ok_obligations(ok)
-    }
 }
diff --git a/compiler/rustc_hir_typeck/src/lib.rs b/compiler/rustc_hir_typeck/src/lib.rs
index 5104b448023..11c56b5fce6 100644
--- a/compiler/rustc_hir_typeck/src/lib.rs
+++ b/compiler/rustc_hir_typeck/src/lib.rs
@@ -48,6 +48,8 @@ pub use diverges::Diverges;
 pub use expectation::Expectation;
 pub use fn_ctxt::*;
 pub use inherited::{Inherited, InheritedBuilder};
+use rustc_infer::traits::ObligationCause;
+use rustc_trait_selection::traits::NormalizeExt;
 
 use crate::check::check_fn;
 use crate::coercion::DynamicCoerceMany;
@@ -245,12 +247,13 @@ fn typeck_with_fallback<'tcx>(
 
             // Compute the function signature from point of view of inside the fn.
             let fn_sig = tcx.liberate_late_bound_regions(def_id.to_def_id(), fn_sig);
-            let fn_sig = inh.normalize_associated_types_in(
-                body.value.span,
-                body_id.hir_id,
-                param_env,
-                fn_sig,
-            );
+            // FIXME(compiler-errors): Remove
+            let fn_sig = inh
+                .register_infer_ok_obligations(
+                    inh.at(&ObligationCause::misc(body.value.span, body_id.hir_id),
+                    param_env,
+                )
+                .normalize(fn_sig));
             check_fn(&inh, param_env, fn_sig, decl, def_id, body, None).0
         } else {
             let fcx = FnCtxt::new(&inh, param_env, body.value.hir_id);
@@ -304,7 +307,7 @@ fn typeck_with_fallback<'tcx>(
                     _ => fallback(),
                 });
 
-            let expected_type = fcx.normalize_associated_types_in(body.value.span, expected_type);
+            let expected_type = fcx.normalize(body.value.span, expected_type);
             fcx.require_type_is_sized(expected_type, body.value.span, traits::ConstSized);
 
             // Gather locals in statics (because of block expressions).
diff --git a/compiler/rustc_hir_typeck/src/method/confirm.rs b/compiler/rustc_hir_typeck/src/method/confirm.rs
index f50a16dcb23..03d0e7926de 100644
--- a/compiler/rustc_hir_typeck/src/method/confirm.rs
+++ b/compiler/rustc_hir_typeck/src/method/confirm.rs
@@ -106,7 +106,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
         // traits, no trait system method can be called before this point because they
         // could alter our Self-type, except for normalizing the receiver from the
         // signature (which is also done during probing).
-        let method_sig_rcvr = self.normalize_associated_types_in(self.span, method_sig.inputs()[0]);
+        let method_sig_rcvr = self.normalize(self.span, method_sig.inputs()[0]);
         debug!(
             "confirm: self_ty={:?} method_sig_rcvr={:?} method_sig={:?} method_predicates={:?}",
             self_ty, method_sig_rcvr, method_sig, method_predicates
@@ -114,7 +114,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
         self.unify_receivers(self_ty, method_sig_rcvr, &pick, all_substs);
 
         let (method_sig, method_predicates) =
-            self.normalize_associated_types_in(self.span, (method_sig, method_predicates));
+            self.normalize(self.span, (method_sig, method_predicates));
         let method_sig = ty::Binder::dummy(method_sig);
 
         // Make sure nobody calls `drop()` explicitly.
diff --git a/src/tools/clippy/clippy_utils/src/ty.rs b/src/tools/clippy/clippy_utils/src/ty.rs
index 82496f120e3..2ceda3511fe 100644
--- a/src/tools/clippy/clippy_utils/src/ty.rs
+++ b/src/tools/clippy/clippy_utils/src/ty.rs
@@ -22,8 +22,7 @@ use rustc_span::symbol::Ident;
 use rustc_span::{sym, Span, Symbol, DUMMY_SP};
 use rustc_target::abi::{Size, VariantIdx};
 use rustc_trait_selection::infer::InferCtxtExt;
-use rustc_trait_selection::traits::NormalizeExt;
-use rustc_trait_selection::traits::query::normalize::AtExt;
+use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt;
 use std::iter;
 
 use crate::{match_def_path, path_res, paths};
@@ -284,7 +283,7 @@ fn is_normalizable_helper<'tcx>(
     cache.insert(ty, false);
     let infcx = cx.tcx.infer_ctxt().build();
     let cause = rustc_middle::traits::ObligationCause::dummy();
-    let result = if infcx.at(&cause, param_env).normalize(ty).is_ok() {
+    let result = if infcx.at(&cause, param_env).query_normalize(ty).is_ok() {
         match ty.kind() {
             ty::Adt(def, substs) => def.variants().iter().all(|variant| {
                 variant