Remove GeneratorWitness and rename GeneratorWitnessMIR.

10 files changed, 13 insertions, 65 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs
index 59f712721fb..acab4498a09 100644
--- a/compiler/rustc_trait_selection/src/traits/coherence.rs
+++ b/compiler/rustc_trait_selection/src/traits/coherence.rs
@@ -827,9 +827,7 @@ where
             // This should only be created when checking whether we have to check whether some
             // auto trait impl applies. There will never be multiple impls, so we can just
             // act as if it were a local type here.
-            ty::GeneratorWitness(_) | ty::GeneratorWitnessMIR(..) => {
-                ControlFlow::Break(OrphanCheckEarlyExit::LocalTy(ty))
-            }
+            ty::GeneratorWitness(..) => ControlFlow::Break(OrphanCheckEarlyExit::LocalTy(ty)),
             ty::Alias(ty::Opaque, ..) => {
                 // This merits some explanation.
                 // Normally, opaque types are not involved when performing
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
index d3e0d3b8b18..2a333a4f0e3 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -1847,7 +1847,6 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                 ty::Generator(..) => Some(18),
                 ty::Foreign(..) => Some(19),
                 ty::GeneratorWitness(..) => Some(20),
-                ty::GeneratorWitnessMIR(..) => Some(21),
                 ty::Placeholder(..) | ty::Bound(..) | ty::Infer(..) | ty::Error(_) => None,
             }
         }
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index 428267a923e..748ecdc01b4 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -2173,11 +2173,10 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     );
 
                     match *ty.kind() {
-                        ty::Generator(did, ..) | ty::GeneratorWitnessMIR(did, _) => {
+                        ty::Generator(did, ..) | ty::GeneratorWitness(did, _) => {
                             generator = generator.or(Some(did));
                             outer_generator = Some(did);
                         }
-                        ty::GeneratorWitness(..) => {}
                         ty::Tuple(_) if !seen_upvar_tys_infer_tuple => {
                             // By introducing a tuple of upvar types into the chain of obligations
                             // of a generator, the first non-generator item is now the tuple itself,
@@ -2203,11 +2202,10 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     );
 
                     match *ty.kind() {
-                        ty::Generator(did, ..) | ty::GeneratorWitnessMIR(did, ..) => {
+                        ty::Generator(did, ..) | ty::GeneratorWitness(did, ..) => {
                             generator = generator.or(Some(did));
                             outer_generator = Some(did);
                         }
-                        ty::GeneratorWitness(..) => {}
                         ty::Tuple(_) if !seen_upvar_tys_infer_tuple => {
                             // By introducing a tuple of upvar types into the chain of obligations
                             // of a generator, the first non-generator item is now the tuple itself,
@@ -2987,20 +2985,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 }
                                 err.span_note(self.tcx.def_span(def_id), msg)
                             }
-                            ty::GeneratorWitness(bound_tys) => {
-                                use std::fmt::Write;
-
-                                // FIXME: this is kind of an unusual format for rustc, can we make it more clear?
-                                // Maybe we should just remove this note altogether?
-                                // FIXME: only print types which don't meet the trait requirement
-                                let mut msg =
-                                    "required because it captures the following types: ".to_owned();
-                                for ty in bound_tys.skip_binder() {
-                                    with_forced_trimmed_paths!(write!(msg, "`{ty}`, ").unwrap());
-                                }
-                                err.note(msg.trim_end_matches(", ").to_string())
-                            }
-                            ty::GeneratorWitnessMIR(def_id, args) => {
+                            ty::GeneratorWitness(def_id, args) => {
                                 use std::fmt::Write;
 
                                 // FIXME: this is kind of an unusual format for rustc, can we make it more clear?
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 93e8e1f4bb1..154cc7a7141 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -1813,7 +1813,6 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         | ty::Closure(..)
                         | ty::Generator(..)
                         | ty::GeneratorWitness(..)
-                        | ty::GeneratorWitnessMIR(..)
                         | ty::Never
                         | ty::Tuple(..)
                         // Integers and floats always have `u8` as their discriminant.
@@ -1863,7 +1862,6 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         | ty::Closure(..)
                         | ty::Generator(..)
                         | ty::GeneratorWitness(..)
-                        | ty::GeneratorWitnessMIR(..)
                         | ty::Never
                         // Extern types have unit metadata, according to RFC 2850
                         | ty::Foreign(_)
diff --git a/compiler/rustc_trait_selection/src/traits/query/dropck_outlives.rs b/compiler/rustc_trait_selection/src/traits/query/dropck_outlives.rs
index 9484a50e3a9..86ea7a2bf83 100644
--- a/compiler/rustc_trait_selection/src/traits/query/dropck_outlives.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/dropck_outlives.rs
@@ -36,7 +36,6 @@ pub fn trivial_dropck_outlives<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
         | ty::FnPtr(_)
         | ty::Char
         | ty::GeneratorWitness(..)
-        | ty::GeneratorWitnessMIR(..)
         | ty::RawPtr(_)
         | ty::Ref(..)
         | ty::Str
@@ -218,8 +217,7 @@ pub fn dtorck_constraint_for_ty_inner<'tcx>(
         | ty::Ref(..)
         | ty::FnDef(..)
         | ty::FnPtr(_)
-        | ty::GeneratorWitness(..)
-        | ty::GeneratorWitnessMIR(..) => {
+        | ty::GeneratorWitness(..) => {
             // these types never have a destructor
         }
 
diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
index e3da87a2210..bead8758ad6 100644
--- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs
@@ -436,8 +436,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 | ty::Ref(_, _, _)
                 | ty::Closure(_, _)
                 | ty::Generator(_, _, _)
-                | ty::GeneratorWitness(_)
-                | ty::GeneratorWitnessMIR(_, _)
+                | ty::GeneratorWitness(..)
                 | ty::Never
                 | ty::Tuple(_)
                 | ty::Error(_) => return true,
@@ -569,8 +568,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 | ty::Generator(..)
                 | ty::Never
                 | ty::Tuple(_)
-                | ty::GeneratorWitness(_)
-                | ty::GeneratorWitnessMIR(..) => {
+                | ty::GeneratorWitness(..) => {
                     // Only consider auto impls if there are no manual impls for the root of `self_ty`.
                     //
                     // For example, we only consider auto candidates for `&i32: Auto` if no explicit impl
@@ -946,8 +944,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             | ty::Closure(..)
             | ty::Generator(..)
             | ty::Tuple(_)
-            | ty::GeneratorWitness(_)
-            | ty::GeneratorWitnessMIR(..) => {
+            | ty::GeneratorWitness(..) => {
                 // These are built-in, and cannot have a custom `impl const Destruct`.
                 candidates.vec.push(ConstDestructCandidate(None));
             }
@@ -1020,8 +1017,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             | ty::Dynamic(_, _, _)
             | ty::Closure(_, _)
             | ty::Generator(_, _, _)
-            | ty::GeneratorWitness(_)
-            | ty::GeneratorWitnessMIR(..)
+            | ty::GeneratorWitness(..)
             | ty::Never
             | ty::Alias(..)
             | ty::Param(_)
@@ -1083,7 +1079,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             | ty::Closure(..)
             | ty::Generator(..)
             | ty::GeneratorWitness(..)
-            | ty::GeneratorWitnessMIR(..)
             | ty::Never
             | ty::Tuple(..)
             | ty::Alias(..)
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index eadac70057c..08ee9c73bf8 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -1238,10 +1238,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                     let generator = args.as_generator();
                     stack.extend([generator.tupled_upvars_ty(), generator.witness()]);
                 }
-                ty::GeneratorWitness(tys) => {
-                    stack.extend(tcx.erase_late_bound_regions(tys).to_vec());
-                }
-                ty::GeneratorWitnessMIR(def_id, args) => {
+                ty::GeneratorWitness(def_id, args) => {
                     let tcx = self.tcx();
                     stack.extend(tcx.generator_hidden_types(def_id).map(|bty| {
                         let ty = bty.instantiate(tcx, args);
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index d4ca0c8a5c5..7d672e658c7 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -2131,7 +2131,6 @@ impl<'tcx> SelectionContext<'_, 'tcx> {
             | ty::Ref(..)
             | ty::Generator(..)
             | ty::GeneratorWitness(..)
-            | ty::GeneratorWitnessMIR(..)
             | ty::Array(..)
             | ty::Closure(..)
             | ty::Never
@@ -2230,22 +2229,7 @@ impl<'tcx> SelectionContext<'_, 'tcx> {
                 }
             }
 
-            ty::GeneratorWitness(binder) => {
-                let witness_tys = binder.skip_binder();
-                for witness_ty in witness_tys.iter() {
-                    let resolved = self.infcx.shallow_resolve(witness_ty);
-                    if resolved.is_ty_var() {
-                        return Ambiguous;
-                    }
-                }
-                // (*) binder moved here
-                let all_vars = self.tcx().mk_bound_variable_kinds_from_iter(
-                    obligation.predicate.bound_vars().iter().chain(binder.bound_vars().iter()),
-                );
-                Where(ty::Binder::bind_with_vars(witness_tys.to_vec(), all_vars))
-            }
-
-            ty::GeneratorWitnessMIR(def_id, ref args) => {
+            ty::GeneratorWitness(def_id, ref args) => {
                 let hidden_types = bind_generator_hidden_types_above(
                     self.infcx,
                     def_id,
@@ -2350,12 +2334,7 @@ impl<'tcx> SelectionContext<'_, 'tcx> {
                 t.rebind([ty].into_iter().chain(iter::once(witness)).collect())
             }
 
-            ty::GeneratorWitness(types) => {
-                debug_assert!(!types.has_escaping_bound_vars());
-                types.map_bound(|types| types.to_vec())
-            }
-
-            ty::GeneratorWitnessMIR(def_id, ref args) => {
+            ty::GeneratorWitness(def_id, ref args) => {
                 bind_generator_hidden_types_above(self.infcx, def_id, args, t.bound_vars())
             }
 
diff --git a/compiler/rustc_trait_selection/src/traits/structural_match.rs b/compiler/rustc_trait_selection/src/traits/structural_match.rs
index 0864e4dc841..fc9b424369a 100644
--- a/compiler/rustc_trait_selection/src/traits/structural_match.rs
+++ b/compiler/rustc_trait_selection/src/traits/structural_match.rs
@@ -79,7 +79,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for Search<'tcx> {
             ty::Closure(..) => {
                 return ControlFlow::Break(ty);
             }
-            ty::Generator(..) | ty::GeneratorWitness(..) | ty::GeneratorWitnessMIR(..) => {
+            ty::Generator(..) | ty::GeneratorWitness(..) => {
                 return ControlFlow::Break(ty);
             }
             ty::FnDef(..) => {
diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index f26310665f9..b04008d9ee5 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -609,7 +609,6 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
                 | ty::Error(_)
                 | ty::Str
                 | ty::GeneratorWitness(..)
-                | ty::GeneratorWitnessMIR(..)
                 | ty::Never
                 | ty::Param(_)
                 | ty::Bound(..)