Rename many interner functions.

(This is a large commit. The changes to
`compiler/rustc_middle/src/ty/context.rs` are the most important ones.)

The current naming scheme is a mess, with a mix of `_intern_`, `intern_`
and `mk_` prefixes, with little consistency. In particular, in many
cases it's easy to use an iterator interner when a (preferable) slice
interner is available.

The guiding principles of the new naming system:
- No `_intern_` prefixes.
- The `intern_` prefix is for internal operations.
- The `mk_` prefix is for external operations.
- For cases where there is a slice interner and an iterator interner,
  the former is `mk_foo` and the latter is `mk_foo_from_iter`.

Also, `slice_interners!` and `direct_interners!` can now be `pub` or
non-`pub`, which helps enforce the internal/external operations
division.

It's not perfect, but I think it's a clear improvement.

The following lists show everything that was renamed.

slice_interners
- const_list
  - mk_const_list -> mk_const_list_from_iter
  - intern_const_list -> mk_const_list
- substs
  - mk_substs -> mk_substs_from_iter
  - intern_substs -> mk_substs
  - check_substs -> check_and_mk_substs (this is a weird one)
- canonical_var_infos
  - intern_canonical_var_infos -> mk_canonical_var_infos
- poly_existential_predicates
  - mk_poly_existential_predicates -> mk_poly_existential_predicates_from_iter
  - intern_poly_existential_predicates -> mk_poly_existential_predicates
  - _intern_poly_existential_predicates -> intern_poly_existential_predicates
- predicates
  - mk_predicates -> mk_predicates_from_iter
  - intern_predicates -> mk_predicates
  - _intern_predicates -> intern_predicates
- projs
  - intern_projs -> mk_projs
- place_elems
  - mk_place_elems -> mk_place_elems_from_iter
  - intern_place_elems -> mk_place_elems
- bound_variable_kinds
  - mk_bound_variable_kinds -> mk_bound_variable_kinds_from_iter
  - intern_bound_variable_kinds -> mk_bound_variable_kinds

direct_interners
- region
  - intern_region (unchanged)
- const
  - mk_const_internal -> intern_const
- const_allocation
  - intern_const_alloc -> mk_const_alloc
- layout
  - intern_layout -> mk_layout
- adt_def
  - intern_adt_def -> mk_adt_def_from_data (unusual case, hard to avoid)
  - alloc_adt_def(!) -> mk_adt_def
- external_constraints
  - intern_external_constraints -> mk_external_constraints

Other
- type_list
  - mk_type_list -> mk_type_list_from_iter
  - intern_type_list -> mk_type_list
- tup
  - mk_tup -> mk_tup_from_iter
  - intern_tup -> mk_tup

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -1494,7 +1494,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         assert!(root_place.projection.is_empty());
         let proper_span = self.body.local_decls[root_place.local].source_info.span;
 
-        let root_place_projection = self.infcx.tcx.intern_place_elems(root_place.projection);
+        let root_place_projection = self.infcx.tcx.mk_place_elems(root_place.projection);
 
         if self.access_place_error_reported.contains(&(
             Place { local: root_place.local, projection: root_place_projection },

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -2633,7 +2633,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             DefKind::InlineConst => substs.as_inline_const().parent_substs(),
             other => bug!("unexpected item {:?}", other),
         };
-        let parent_substs = tcx.intern_substs(parent_substs);
+        let parent_substs = tcx.mk_substs(parent_substs);
 
         assert_eq!(typeck_root_substs.len(), parent_substs.len());
         if let Err(_) = self.eq_substs(

compiler/rustc_borrowck/src/universal_regions.rs

@@ -516,7 +516,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 let va_list_ty =
                     self.infcx.tcx.type_of(va_list_did).subst(self.infcx.tcx, &[region.into()]);
 
-                unnormalized_input_tys = self.infcx.tcx.mk_type_list(
+                unnormalized_input_tys = self.infcx.tcx.mk_type_list_from_iter(
                     unnormalized_input_tys.iter().copied().chain(iter::once(va_list_ty)),
                 );
             }
@@ -656,7 +656,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 assert_eq!(self.mir_def.did.to_def_id(), def_id);
                 let closure_sig = substs.as_closure().sig();
                 let inputs_and_output = closure_sig.inputs_and_output();
-                let bound_vars = tcx.mk_bound_variable_kinds(
+                let bound_vars = tcx.mk_bound_variable_kinds_from_iter(
                     inputs_and_output
                         .bound_vars()
                         .iter()
@@ -680,7 +680,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 };
 
                 ty::Binder::bind_with_vars(
-                    tcx.mk_type_list(
+                    tcx.mk_type_list_from_iter(
                         iter::once(closure_ty).chain(inputs).chain(iter::once(output)),
                     ),
                     bound_vars,
@@ -693,7 +693,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 let output = substs.as_generator().return_ty();
                 let generator_ty = tcx.mk_generator(def_id, substs, movability);
                 let inputs_and_output =
-                    self.infcx.tcx.intern_type_list(&[generator_ty, resume_ty, output]);
+                    self.infcx.tcx.mk_type_list(&[generator_ty, resume_ty, output]);
                 ty::Binder::dummy(inputs_and_output)
             }
 
@@ -709,13 +709,13 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 assert_eq!(self.mir_def.did.to_def_id(), def_id);
                 let ty = tcx.type_of(self.mir_def.def_id_for_type_of()).subst_identity();
                 let ty = indices.fold_to_region_vids(tcx, ty);
-                ty::Binder::dummy(tcx.intern_type_list(&[ty]))
+                ty::Binder::dummy(tcx.mk_type_list(&[ty]))
             }
 
             DefiningTy::InlineConst(def_id, substs) => {
                 assert_eq!(self.mir_def.did.to_def_id(), def_id);
                 let ty = substs.as_inline_const().ty();
-                ty::Binder::dummy(tcx.intern_type_list(&[ty]))
+                ty::Binder::dummy(tcx.mk_type_list(&[ty]))
             }
         }
     }

compiler/rustc_codegen_cranelift/src/abi/mod.rs

@@ -405,9 +405,9 @@ pub(crate) fn codegen_terminator_call<'tcx>(
     };
 
     let extra_args = &args[fn_sig.inputs().skip_binder().len()..];
-    let extra_args = fx
+    let extra_args = fx.tcx.mk_type_list_from_iter(
-        .tcx
+        extra_args.iter().map(|op_arg| fx.monomorphize(op_arg.ty(fx.mir, fx.tcx))),
-        .mk_type_list(extra_args.iter().map(|op_arg| fx.monomorphize(op_arg.ty(fx.mir, fx.tcx))));
+    );
     let fn_abi = if let Some(instance) = instance {
         RevealAllLayoutCx(fx.tcx).fn_abi_of_instance(instance, extra_args)
     } else {

compiler/rustc_codegen_cranelift/src/codegen_i128.rs

@@ -56,7 +56,7 @@ pub(crate) fn maybe_codegen<'tcx>(
                     Some(fx.easy_call("__multi3", &[lhs, rhs], val_ty))
                 }
             } else {
-                let out_ty = fx.tcx.intern_tup(&[lhs.layout().ty, fx.tcx.types.bool]);
+                let out_ty = fx.tcx.mk_tup(&[lhs.layout().ty, fx.tcx.types.bool]);
                 let oflow = CPlace::new_stack_slot(fx, fx.layout_of(fx.tcx.types.i32));
                 let lhs = lhs.load_scalar(fx);
                 let rhs = rhs.load_scalar(fx);
@@ -78,7 +78,7 @@ pub(crate) fn maybe_codegen<'tcx>(
         }
         BinOp::Add | BinOp::Sub | BinOp::Mul => {
             assert!(checked);
-            let out_ty = fx.tcx.intern_tup(&[lhs.layout().ty, fx.tcx.types.bool]);
+            let out_ty = fx.tcx.mk_tup(&[lhs.layout().ty, fx.tcx.types.bool]);
             let out_place = CPlace::new_stack_slot(fx, fx.layout_of(out_ty));
             let (param_types, args) = if fx.tcx.sess.target.is_like_windows {
                 let (lhs_ptr, lhs_extra) = lhs.force_stack(fx);

compiler/rustc_codegen_cranelift/src/intrinsics/llvm_x86.rs

@@ -191,7 +191,7 @@ fn llvm_add_sub<'tcx>(
     // carry0 | carry1 -> carry or borrow respectively
     let cb_out = fx.bcx.ins().bor(cb0, cb1);
 
-    let layout = fx.layout_of(fx.tcx.intern_tup(&[fx.tcx.types.u8, fx.tcx.types.u64]));
+    let layout = fx.layout_of(fx.tcx.mk_tup(&[fx.tcx.types.u8, fx.tcx.types.u64]));
     let val = CValue::by_val_pair(cb_out, c, layout);
     ret.write_cvalue(fx, val);
 }

compiler/rustc_codegen_cranelift/src/main_shim.rs

@@ -119,7 +119,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                     tcx,
                     ParamEnv::reveal_all(),
                     report.def_id,
-                    tcx.intern_substs(&[GenericArg::from(main_ret_ty)]),
+                    tcx.mk_substs(&[GenericArg::from(main_ret_ty)]),
                 )
                 .unwrap()
                 .unwrap()
@@ -146,7 +146,7 @@ pub(crate) fn maybe_create_entry_wrapper(
                     tcx,
                     ParamEnv::reveal_all(),
                     start_def_id,
-                    tcx.intern_substs(&[main_ret_ty.into()]),
+                    tcx.mk_substs(&[main_ret_ty.into()]),
                 )
                 .unwrap()
                 .unwrap()

compiler/rustc_codegen_cranelift/src/num.rs

@@ -289,7 +289,7 @@ pub(crate) fn codegen_checked_int_binop<'tcx>(
         _ => bug!("binop {:?} on checked int/uint lhs: {:?} rhs: {:?}", bin_op, in_lhs, in_rhs),
     };
 
-    let out_layout = fx.layout_of(fx.tcx.intern_tup(&[in_lhs.layout().ty, fx.tcx.types.bool]));
+    let out_layout = fx.layout_of(fx.tcx.mk_tup(&[in_lhs.layout().ty, fx.tcx.types.bool]));
     CValue::by_val_pair(res, has_overflow, out_layout)
 }
 

compiler/rustc_codegen_gcc/src/context.rs

@@ -383,7 +383,7 @@ impl<'gcc, 'tcx> MiscMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
                     tcx,
                     ty::ParamEnv::reveal_all(),
                     def_id,
-                    tcx.intern_substs(&[]),
+                    tcx.mk_substs(&[]),
                 )
                 .unwrap().unwrap(),
             ),

compiler/rustc_codegen_llvm/src/context.rs

@@ -520,14 +520,9 @@ impl<'ll, 'tcx> MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         let tcx = self.tcx;
         let llfn = match tcx.lang_items().eh_personality() {
             Some(def_id) if !wants_msvc_seh(self.sess()) => self.get_fn_addr(
-                ty::Instance::resolve(
+                ty::Instance::resolve(tcx, ty::ParamEnv::reveal_all(), def_id, tcx.mk_substs(&[]))
-                    tcx,
+                    .unwrap()
-                    ty::ParamEnv::reveal_all(),
+                    .unwrap(),
-                    def_id,
-                    tcx.intern_substs(&[]),
-                )
-                .unwrap()
-                .unwrap(),
             ),
             _ => {
                 let name = if wants_msvc_seh(self.sess()) {

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -373,7 +373,7 @@ fn upstream_monomorphizations_provider(
                 ExportedSymbol::Generic(def_id, substs) => (def_id, substs),
                 ExportedSymbol::DropGlue(ty) => {
                     if let Some(drop_in_place_fn_def_id) = drop_in_place_fn_def_id {
-                        (drop_in_place_fn_def_id, tcx.intern_substs(&[ty.into()]))
+                        (drop_in_place_fn_def_id, tcx.mk_substs(&[ty.into()]))
                     } else {
                         // `drop_in_place` in place does not exist, don't try
                         // to use it.

compiler/rustc_codegen_ssa/src/base.rs

@@ -476,7 +476,7 @@ pub fn maybe_create_entry_wrapper<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                     cx.tcx(),
                     ty::ParamEnv::reveal_all(),
                     start_def_id,
-                    cx.tcx().intern_substs(&[main_ret_ty.into()]),
+                    cx.tcx().mk_substs(&[main_ret_ty.into()]),
                 )
                 .unwrap()
                 .unwrap(),

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -783,7 +783,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         };
 
         let extra_args = &args[sig.inputs().skip_binder().len()..];
-        let extra_args = bx.tcx().mk_type_list(extra_args.iter().map(|op_arg| {
+        let extra_args = bx.tcx().mk_type_list_from_iter(extra_args.iter().map(|op_arg| {
             let op_ty = op_arg.ty(self.mir, bx.tcx());
             self.monomorphize(op_ty)
         }));
@@ -1547,7 +1547,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             slot
         } else {
             let layout = cx.layout_of(
-                cx.tcx().intern_tup(&[cx.tcx().mk_mut_ptr(cx.tcx().types.u8), cx.tcx().types.i32]),
+                cx.tcx().mk_tup(&[cx.tcx().mk_mut_ptr(cx.tcx().types.u8), cx.tcx().types.i32]),
             );
             let slot = PlaceRef::alloca(bx, layout);
             self.personality_slot = Some(slot);

compiler/rustc_codegen_ssa/src/mir/rvalue.rs

@@ -413,7 +413,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                     lhs.layout.ty,
                 );
                 let val_ty = op.ty(bx.tcx(), lhs.layout.ty, rhs.layout.ty);
-                let operand_ty = bx.tcx().intern_tup(&[val_ty, bx.tcx().types.bool]);
+                let operand_ty = bx.tcx().mk_tup(&[val_ty, bx.tcx().types.bool]);
                 OperandRef { val: result, layout: bx.cx().layout_of(operand_ty) }
             }
 

compiler/rustc_const_eval/src/const_eval/eval_queries.rs

@@ -180,7 +180,7 @@ pub(super) fn op_to_const<'tcx>(
                         (ecx.tcx.global_alloc(alloc_id).unwrap_memory(), offset.bytes())
                     }
                     (None, _offset) => (
-                        ecx.tcx.intern_const_alloc(Allocation::from_bytes_byte_aligned_immutable(
+                        ecx.tcx.mk_const_alloc(Allocation::from_bytes_byte_aligned_immutable(
                             b"" as &[u8],
                         )),
                         0,

compiler/rustc_const_eval/src/interpret/intern.rs

@@ -135,7 +135,7 @@ fn intern_shallow<'rt, 'mir, 'tcx, M: CompileTimeMachine<'mir, 'tcx, const_eval:
     };
     // link the alloc id to the actual allocation
     leftover_allocations.extend(alloc.provenance().ptrs().iter().map(|&(_, alloc_id)| alloc_id));
-    let alloc = tcx.intern_const_alloc(alloc);
+    let alloc = tcx.mk_const_alloc(alloc);
     tcx.set_alloc_id_memory(alloc_id, alloc);
     None
 }
@@ -437,7 +437,7 @@ pub fn intern_const_alloc_recursive<
                     alloc.mutability = Mutability::Not;
                 }
             }
-            let alloc = tcx.intern_const_alloc(alloc);
+            let alloc = tcx.mk_const_alloc(alloc);
             tcx.set_alloc_id_memory(alloc_id, alloc);
             for &(_, alloc_id) in alloc.inner().provenance().ptrs().iter() {
                 if leftover_allocations.insert(alloc_id) {
@@ -479,6 +479,6 @@ impl<'mir, 'tcx: 'mir, M: super::intern::CompileTimeMachine<'mir, 'tcx, !>>
         f(self, &dest.into())?;
         let mut alloc = self.memory.alloc_map.remove(&dest.ptr.provenance.unwrap()).unwrap().1;
         alloc.mutability = Mutability::Not;
-        Ok(self.tcx.intern_const_alloc(alloc))
+        Ok(self.tcx.mk_const_alloc(alloc))
     }
 }

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -45,7 +45,7 @@ fn numeric_intrinsic<Prov>(name: Symbol, bits: u128, kind: Primitive) -> Scalar<
 pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ConstAllocation<'tcx> {
     let path = crate::util::type_name(tcx, ty);
     let alloc = Allocation::from_bytes_byte_aligned_immutable(path.into_bytes());
-    tcx.intern_const_alloc(alloc)
+    tcx.mk_const_alloc(alloc)
 }
 
 /// The logic for all nullary intrinsics is implemented here. These intrinsics don't get evaluated

compiler/rustc_const_eval/src/interpret/intrinsics/caller_location.rs

@@ -96,7 +96,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         let loc_ty = self
             .tcx
             .type_of(self.tcx.require_lang_item(LangItem::PanicLocation, None))
-            .subst(*self.tcx, self.tcx.intern_substs(&[self.tcx.lifetimes.re_erased.into()]));
+            .subst(*self.tcx, self.tcx.mk_substs(&[self.tcx.lifetimes.re_erased.into()]));
         let loc_layout = self.layout_of(loc_ty).unwrap();
         let location = self.allocate(loc_layout, MemoryKind::CallerLocation).unwrap();
 

compiler/rustc_const_eval/src/interpret/operator.rs

@@ -19,7 +19,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     ) -> InterpResult<'tcx> {
         let (val, overflowed, ty) = self.overflowing_binary_op(op, &left, &right)?;
         debug_assert_eq!(
-            self.tcx.intern_tup(&[ty, self.tcx.types.bool]),
+            self.tcx.mk_tup(&[ty, self.tcx.types.bool]),
             dest.layout.ty,
             "type mismatch for result of {:?}",
             op,

compiler/rustc_const_eval/src/interpret/terminator.rs

@@ -73,7 +73,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let fn_sig =
                     self.tcx.normalize_erasing_late_bound_regions(self.param_env, fn_sig_binder);
                 let extra_args = &args[fn_sig.inputs().len()..];
-                let extra_args = self.tcx.mk_type_list(extra_args.iter().map(|arg| arg.layout.ty));
+                let extra_args =
+                    self.tcx.mk_type_list_from_iter(extra_args.iter().map(|arg| arg.layout.ty));
 
                 let (fn_val, fn_abi, with_caller_location) = match *func.layout.ty.kind() {
                     ty::FnPtr(_sig) => {

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -866,7 +866,7 @@ impl<'a, 'tcx> Promoter<'a, 'tcx> {
 
             let mut projection = vec![PlaceElem::Deref];
             projection.extend(place.projection);
-            place.projection = tcx.intern_place_elems(&projection);
+            place.projection = tcx.mk_place_elems(&projection);
 
             // Create a temp to hold the promoted reference.
             // This is because `*r` requires `r` to be a local,

compiler/rustc_const_eval/src/transform/validate.rs

@@ -315,7 +315,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 }
             }
             ProjectionElem::Field(f, ty) => {
-                let parent = Place { local, projection: self.tcx.intern_place_elems(proj_base) };
+                let parent = Place { local, projection: self.tcx.mk_place_elems(proj_base) };
                 let parent_ty = parent.ty(&self.body.local_decls, self.tcx);
                 let fail_out_of_bounds = |this: &Self, location| {
                     this.fail(location, format!("Out of bounds field {:?} for {:?}", f, parent_ty));

compiler/rustc_hir_analysis/src/astconv/errors.rs

@@ -377,7 +377,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                     // `<Foo as Iterator>::Item = String`.
                     let projection_ty = pred.skip_binder().projection_ty;
 
-                    let substs_with_infer_self = tcx.mk_substs(
+                    let substs_with_infer_self = tcx.mk_substs_from_iter(
                         std::iter::once(tcx.mk_ty_var(ty::TyVid::from_u32(0)).into())
                             .chain(projection_ty.substs.iter().skip(1)),
                     );

compiler/rustc_hir_analysis/src/astconv/generics.rs

@@ -370,7 +370,7 @@ pub fn create_substs_for_generic_args<'tcx, 'a>(
         }
     }
 
-    tcx.intern_substs(&substs)
+    tcx.mk_substs(&substs)
 }
 
 /// Checks that the correct number of generic arguments have been provided.

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -381,7 +381,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
         // here and so associated type bindings will be handled regardless of whether there are any
         // non-`Self` generic parameters.
         if generics.params.is_empty() {
-            return (tcx.intern_substs(parent_substs), arg_count);
+            return (tcx.mk_substs(parent_substs), arg_count);
         }
 
         struct SubstsForAstPathCtxt<'a, 'tcx> {
@@ -1529,7 +1529,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                         arg
                     })
                     .collect();
-                let substs = tcx.intern_substs(&substs[..]);
+                let substs = tcx.mk_substs(&substs);
 
                 let span = i.bottom().1;
                 let empty_generic_args = hir_trait_bounds.iter().any(|hir_bound| {
@@ -1591,7 +1591,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             arg
                         })
                         .collect();
-                    b.projection_ty.substs = tcx.intern_substs(&substs[..]);
+                    b.projection_ty.substs = tcx.mk_substs(&substs);
                 }
 
                 ty::ExistentialProjection::erase_self_ty(tcx, b)
@@ -1613,7 +1613,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
             .collect::<SmallVec<[_; 8]>>();
         v.sort_by(|a, b| a.skip_binder().stable_cmp(tcx, &b.skip_binder()));
         v.dedup();
-        let existential_predicates = tcx.intern_poly_existential_predicates(&v);
+        let existential_predicates = tcx.mk_poly_existential_predicates(&v);
 
         // Use explicitly-specified region bound.
         let region_bound = if !lifetime.is_elided() {
@@ -3020,7 +3020,9 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                 tcx.mk_ref(r, ty::TypeAndMut { ty: t, mutbl: mt.mutbl })
             }
             hir::TyKind::Never => tcx.types.never,
-            hir::TyKind::Tup(fields) => tcx.mk_tup(fields.iter().map(|t| self.ast_ty_to_ty(t))),
+            hir::TyKind::Tup(fields) => {
+                tcx.mk_tup_from_iter(fields.iter().map(|t| self.ast_ty_to_ty(t)))
+            }
             hir::TyKind::BareFn(bf) => {
                 require_c_abi_if_c_variadic(tcx, bf.decl, bf.abi, ast_ty.span);
 

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -196,7 +196,7 @@ 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.intern_predicates(&hybrid_preds.predicates),
+        tcx.mk_predicates(&hybrid_preds.predicates),
         Reveal::UserFacing,
         hir::Constness::NotConst,
     );
@@ -1795,7 +1795,7 @@ 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.intern_predicates(&hybrid_preds.predicates),
+        tcx.mk_predicates(&hybrid_preds.predicates),
         Reveal::UserFacing,
         hir::Constness::NotConst,
     );
@@ -1937,8 +1937,8 @@ pub(super) fn check_type_bounds<'tcx>(
             .into()
         }
     });
-    let bound_vars = tcx.intern_bound_variable_kinds(&bound_vars);
+    let bound_vars = tcx.mk_bound_variable_kinds(&bound_vars);
-    let impl_ty_substs = tcx.intern_substs(&substs);
+    let impl_ty_substs = tcx.mk_substs(&substs);
     let container_id = impl_ty.container_id(tcx);
 
     let rebased_substs = impl_ty_substs.rebase_onto(tcx, container_id, impl_trait_ref.substs);
@@ -1978,11 +1978,7 @@ pub(super) fn check_type_bounds<'tcx>(
                 .to_predicate(tcx),
             ),
         };
-        ty::ParamEnv::new(
+        ty::ParamEnv::new(tcx.mk_predicates(&predicates), Reveal::UserFacing, param_env.constness())
-            tcx.intern_predicates(&predicates),
-            Reveal::UserFacing,
-            param_env.constness(),
-        )
     };
     debug!(?normalize_param_env);
 

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -137,7 +137,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
     let intrinsic_name = tcx.item_name(intrinsic_id);
     let name_str = intrinsic_name.as_str();
 
-    let bound_vars = tcx.intern_bound_variable_kinds(&[
+    let bound_vars = tcx.mk_bound_variable_kinds(&[
         ty::BoundVariableKind::Region(ty::BrAnon(0, None)),
         ty::BoundVariableKind::Region(ty::BrEnv),
     ]);
@@ -165,7 +165,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
             "cxchg" | "cxchgweak" => (
                 1,
                 vec![tcx.mk_mut_ptr(param(0)), param(0), param(0)],
-                tcx.intern_tup(&[param(0), tcx.types.bool]),
+                tcx.mk_tup(&[param(0), tcx.types.bool]),
             ),
             "load" => (1, vec![tcx.mk_imm_ptr(param(0))], param(0)),
             "store" => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
@@ -317,7 +317,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
             | sym::bitreverse => (1, vec![param(0)], param(0)),
 
             sym::add_with_overflow | sym::sub_with_overflow | sym::mul_with_overflow => {
-                (1, vec![param(0), param(0)], tcx.intern_tup(&[param(0), tcx.types.bool]))
+                (1, vec![param(0), param(0)], tcx.mk_tup(&[param(0), tcx.types.bool]))
             }
 
             sym::ptr_guaranteed_cmp => {
@@ -372,7 +372,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
                 (
                     1,
                     vec![tcx.mk_imm_ref(tcx.mk_re_late_bound(ty::INNERMOST, br), param(0))],
-                    tcx.mk_projection(discriminant_def_id, tcx.intern_substs(&[param(0).into()])),
+                    tcx.mk_projection(discriminant_def_id, tcx.mk_substs(&[param(0).into()])),
                 )
             }
 

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -493,8 +493,9 @@ fn augment_param_env<'tcx>(
         return param_env;
     }
 
-    let bounds =
+    let bounds = tcx.mk_predicates_from_iter(
-        tcx.mk_predicates(param_env.caller_bounds().iter().chain(new_predicates.iter().cloned()));
+        param_env.caller_bounds().iter().chain(new_predicates.iter().cloned()),
+    );
     // FIXME(compiler-errors): Perhaps there is a case where we need to normalize this
     // i.e. traits::normalize_param_env_or_error
     ty::ParamEnv::new(bounds, param_env.reveal(), param_env.constness())
@@ -1476,7 +1477,7 @@ fn check_fn_or_method<'tcx>(
         |idx| hir_decl.inputs.get(idx).map_or(hir_decl.output.span(), |arg: &hir::Ty<'_>| arg.span);
 
     sig.inputs_and_output =
-        tcx.mk_type_list(sig.inputs_and_output.iter().enumerate().map(|(idx, ty)| {
+        tcx.mk_type_list_from_iter(sig.inputs_and_output.iter().enumerate().map(|(idx, ty)| {
             wfcx.normalize(
                 arg_span(idx),
                 Some(WellFormedLoc::Param {

compiler/rustc_hir_analysis/src/collect.rs

@@ -905,7 +905,7 @@ fn adt_def(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AdtDef<'_> {
         }
         _ => bug!(),
     };
-    tcx.alloc_adt_def(def_id.to_def_id(), kind, variants, repr)
+    tcx.mk_adt_def(def_id.to_def_id(), kind, variants, repr)
 }
 
 fn trait_def(tcx: TyCtxt<'_>, def_id: DefId) -> ty::TraitDef {

compiler/rustc_hir_analysis/src/collect/item_bounds.rs

@@ -103,7 +103,7 @@ pub(super) fn item_bounds(
     tcx: TyCtxt<'_>,
     def_id: DefId,
 ) -> ty::EarlyBinder<&'_ ty::List<ty::Predicate<'_>>> {
-    let bounds = tcx.mk_predicates(
+    let bounds = tcx.mk_predicates_from_iter(
         util::elaborate_predicates(
             tcx,
             tcx.explicit_item_bounds(def_id).iter().map(|&(bound, _span)| bound),

compiler/rustc_hir_typeck/src/callee.rs

@@ -232,7 +232,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let Some(trait_def_id) = opt_trait_def_id else { continue };
 
             let opt_input_type = opt_arg_exprs.map(|arg_exprs| {
-                self.tcx.mk_tup(arg_exprs.iter().map(|e| {
+                self.tcx.mk_tup_from_iter(arg_exprs.iter().map(|e| {
                     self.next_ty_var(TypeVariableOrigin {
                         kind: TypeVariableOriginKind::TypeInference,
                         span: e.span,

compiler/rustc_hir_typeck/src/closure.rs

@@ -127,7 +127,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // the `closures` table.
         let sig = bound_sig.map_bound(|sig| {
             self.tcx.mk_fn_sig(
-                [self.tcx.intern_tup(sig.inputs())],
+                [self.tcx.mk_tup(sig.inputs())],
                 sig.output(),
                 sig.c_variadic,
                 sig.unsafety,

compiler/rustc_hir_typeck/src/expr.rs

@@ -1492,7 +1492,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             }
             _ => self.check_expr_with_expectation(&e, NoExpectation),
         });
-        let tuple = self.tcx.mk_tup(elt_ts_iter);
+        let tuple = self.tcx.mk_tup_from_iter(elt_ts_iter);
         if let Err(guar) = tuple.error_reported() {
             self.tcx.ty_error(guar)
         } else {

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -102,7 +102,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
             let err_inputs = match tuple_arguments {
                 DontTupleArguments => err_inputs,
-                TupleArguments => vec![self.tcx.intern_tup(&err_inputs)],
+                TupleArguments => vec![self.tcx.mk_tup(&err_inputs)],
             };
 
             self.check_argument_types(
@@ -642,7 +642,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 && provided_arg_tys.len() == formal_and_expected_inputs.len() - 1 + tys.len()
             {
                 // Wrap up the N provided arguments starting at this position in a tuple.
-                let provided_as_tuple = tcx.mk_tup(
+                let provided_as_tuple = tcx.mk_tup_from_iter(
                     provided_arg_tys.iter().map(|(ty, _)| *ty).skip(mismatch_idx).take(tys.len()),
                 );
 

compiler/rustc_hir_typeck/src/generator_interior/mod.rs

@@ -311,8 +311,8 @@ pub fn resolve_interior<'a, 'tcx>(
     };
 
     // Extract type components to build the witness type.
-    let type_list = fcx.tcx.mk_type_list(type_causes.iter().map(|cause| cause.ty));
+    let type_list = fcx.tcx.mk_type_list_from_iter(type_causes.iter().map(|cause| cause.ty));
-    let bound_vars = fcx.tcx.intern_bound_variable_kinds(&bound_vars);
+    let bound_vars = fcx.tcx.mk_bound_variable_kinds(&bound_vars);
     let witness =
         fcx.tcx.mk_generator_witness(ty::Binder::bind_with_vars(type_list, bound_vars.clone()));
 

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -574,7 +574,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         // `<Foo as Iterator>::Item = String`.
                         let projection_ty = pred.skip_binder().projection_ty;
 
-                        let substs_with_infer_self = tcx.mk_substs(
+                        let substs_with_infer_self = tcx.mk_substs_from_iter(
                             iter::once(tcx.mk_ty_var(ty::TyVid::from_u32(0)).into())
                                 .chain(projection_ty.substs.iter().skip(1)),
                         );
@@ -1252,7 +1252,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             if let ty::Adt(def, substs) = target_ty.kind() {
                 // If there are any inferred arguments, (`{integer}`), we should replace
                 // them with underscores to allow the compiler to infer them
-                let infer_substs = self.tcx.mk_substs(substs.into_iter().map(|arg| {
+                let infer_substs = self.tcx.mk_substs_from_iter(substs.into_iter().map(|arg| {
                     if !arg.is_suggestable(self.tcx, true) {
                         has_unsuggestable_args = true;
                         match arg.unpack() {

compiler/rustc_hir_typeck/src/pat.rs

@@ -1302,8 +1302,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 TypeVariableOrigin { kind: TypeVariableOriginKind::TypeInference, span },
             )
         });
-        let element_tys = tcx.mk_type_list(element_tys_iter);
+        let element_tys = tcx.mk_type_list_from_iter(element_tys_iter);
-        let pat_ty = tcx.intern_tup(element_tys);
+        let pat_ty = tcx.mk_tup(element_tys);
         if let Some(mut err) = self.demand_eqtype_pat_diag(span, expected, pat_ty, ti) {
             let reported = err.emit();
             // Walk subpatterns with an expected type of `err` in this case to silence
@@ -1312,7 +1312,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             for (_, elem) in elements.iter().enumerate_and_adjust(max_len, ddpos) {
                 self.check_pat(elem, tcx.ty_error(reported), def_bm, ti);
             }
-            tcx.mk_tup(element_tys_iter)
+            tcx.mk_tup_from_iter(element_tys_iter)
         } else {
             for (i, elem) in elements.iter().enumerate_and_adjust(max_len, ddpos) {
                 self.check_pat(elem, element_tys[i], def_bm, ti);

compiler/rustc_hir_typeck/src/upvar.rs

@@ -301,7 +301,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Build a tuple (U0..Un) of the final upvar types U0..Un
         // and unify the upvar tuple type in the closure with it:
-        let final_tupled_upvars_type = self.tcx.intern_tup(&final_upvar_tys);
+        let final_tupled_upvars_type = self.tcx.mk_tup(&final_upvar_tys);
         self.demand_suptype(span, substs.tupled_upvars_ty(), final_tupled_upvars_type);
 
         let fake_reads = delegate
@@ -315,8 +315,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             self.typeck_results.borrow_mut().closure_size_eval.insert(
                 closure_def_id,
                 ClosureSizeProfileData {
-                    before_feature_tys: self.tcx.intern_tup(&before_feature_tys),
+                    before_feature_tys: self.tcx.mk_tup(&before_feature_tys),
-                    after_feature_tys: self.tcx.intern_tup(&after_feature_tys),
+                    after_feature_tys: self.tcx.mk_tup(&after_feature_tys),
                 },
             );
         }

compiler/rustc_infer/src/infer/canonical/canonicalizer.rs

@@ -572,7 +572,7 @@ impl<'cx, 'tcx> Canonicalizer<'cx, 'tcx> {
         debug_assert!(!out_value.needs_infer() && !out_value.has_placeholders());
 
         let canonical_variables =
-            tcx.intern_canonical_var_infos(&canonicalizer.universe_canonicalized_variables());
+            tcx.mk_canonical_var_infos(&canonicalizer.universe_canonicalized_variables());
 
         let max_universe = canonical_variables
             .iter()

compiler/rustc_infer/src/infer/canonical/mod.rs

@@ -88,7 +88,7 @@ impl<'tcx> InferCtxt<'tcx> {
         universe_map: impl Fn(ty::UniverseIndex) -> ty::UniverseIndex,
     ) -> CanonicalVarValues<'tcx> {
         CanonicalVarValues {
-            var_values: self.tcx.mk_substs(
+            var_values: self.tcx.mk_substs_from_iter(
                 variables
                     .iter()
                     .map(|info| self.instantiate_canonical_var(span, info, &universe_map)),

compiler/rustc_infer/src/infer/canonical/query_response.rs

@@ -474,8 +474,8 @@ impl<'tcx> InferCtxt<'tcx> {
         // given variable in the loop above, use that. Otherwise, use
         // a fresh inference variable.
         let result_subst = CanonicalVarValues {
-            var_values: self.tcx.mk_substs(query_response.variables.iter().enumerate().map(
+            var_values: self.tcx.mk_substs_from_iter(
-                |(index, info)| {
+                query_response.variables.iter().enumerate().map(|(index, info)| {
                     if info.is_existential() {
                         match opt_values[BoundVar::new(index)] {
                             Some(k) => k,
@@ -488,8 +488,8 @@ impl<'tcx> InferCtxt<'tcx> {
                             universe_map[u.as_usize()]
                         })
                     }
-                },
+                }),
-            )),
+            ),
         };
 
         let mut obligations = vec![];

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -925,7 +925,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
     ) -> Option<()> {
         // FIXME/HACK: Go back to `SubstsRef` to use its inherent methods,
         // ideally that shouldn't be necessary.
-        let sub = self.tcx.intern_substs(sub);
+        let sub = self.tcx.mk_substs(sub);
         for (i, ta) in sub.types().enumerate() {
             if ta == other_ty {
                 self.highlight_outer(&mut t1_out, &mut t2_out, path, sub, i, other_ty);

compiler/rustc_lint/src/builtin.rs

@@ -677,21 +677,21 @@ impl<'tcx> LateLintPass<'tcx> for MissingCopyImplementations {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
-                (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
+                (def, cx.tcx.mk_adt(def, cx.tcx.mk_substs(&[])))
             }
             hir::ItemKind::Union(_, ref ast_generics) => {
                 if !ast_generics.params.is_empty() {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
-                (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
+                (def, cx.tcx.mk_adt(def, cx.tcx.mk_substs(&[])))
             }
             hir::ItemKind::Enum(_, ref ast_generics) => {
                 if !ast_generics.params.is_empty() {
                     return;
                 }
                 let def = cx.tcx.adt_def(item.owner_id);
-                (def, cx.tcx.mk_adt(def, cx.tcx.intern_substs(&[])))
+                (def, cx.tcx.mk_adt(def, cx.tcx.mk_substs(&[])))
             }
             _ => return,
         };

compiler/rustc_metadata/src/native_libs.rs

@@ -502,7 +502,7 @@ impl<'tcx> Collector<'tcx> {
                 .subst_identity()
                 .fn_sig(self.tcx)
                 .inputs()
-                .map_bound(|slice| self.tcx.intern_type_list(slice)),
+                .map_bound(|slice| self.tcx.mk_type_list(slice)),
         );
 
         argument_types

compiler/rustc_metadata/src/rmeta/decoder.rs

@@ -910,7 +910,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
             std::iter::once(self.get_variant(&kind, item_id, did)).collect()
         };
 
-        tcx.alloc_adt_def(did, adt_kind, variants, repr)
+        tcx.mk_adt_def(did, adt_kind, variants, repr)
     }
 
     fn get_generics(self, item_id: DefIndex, sess: &Session) -> ty::Generics {

compiler/rustc_middle/src/infer/canonical.rs

@@ -47,7 +47,7 @@ impl<'tcx> ty::TypeFoldable<TyCtxt<'tcx>> for CanonicalVarInfos<'tcx> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_canonical_var_infos(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_canonical_var_infos(v))
     }
 }
 
@@ -342,7 +342,7 @@ impl<'tcx> CanonicalVarValues<'tcx> {
         infos: CanonicalVarInfos<'tcx>,
     ) -> CanonicalVarValues<'tcx> {
         CanonicalVarValues {
-            var_values: tcx.mk_substs(infos.iter().enumerate().map(
+            var_values: tcx.mk_substs_from_iter(infos.iter().enumerate().map(
                 |(i, info)| -> ty::GenericArg<'tcx> {
                     match info.kind {
                         CanonicalVarKind::Ty(_) | CanonicalVarKind::PlaceholderTy(_) => {

compiler/rustc_middle/src/mir/mod.rs

@@ -1620,7 +1620,7 @@ impl<'tcx> Place<'tcx> {
             &v
         };
 
-        Place { local: self.local, projection: tcx.intern_place_elems(new_projections) }
+        Place { local: self.local, projection: tcx.mk_place_elems(new_projections) }
     }
 }
 
@@ -2530,13 +2530,14 @@ impl<'tcx> ConstantKind<'tcx> {
         {
             InternalSubsts::identity_for_item(tcx, parent_did.to_def_id())
         } else {
-            tcx.intern_substs(&[])
+            tcx.mk_substs(&[])
         };
         debug!(?parent_substs);
 
         let did = def.did.to_def_id();
         let child_substs = InternalSubsts::identity_for_item(tcx, did);
-        let substs = tcx.mk_substs(parent_substs.into_iter().chain(child_substs.into_iter()));
+        let substs =
+            tcx.mk_substs_from_iter(parent_substs.into_iter().chain(child_substs.into_iter()));
         debug!(?substs);
 
         let hir_id = tcx.hir().local_def_id_to_hir_id(def.did);

compiler/rustc_middle/src/mir/tcx.rs

@@ -194,14 +194,16 @@ impl<'tcx> Rvalue<'tcx> {
                 let lhs_ty = lhs.ty(local_decls, tcx);
                 let rhs_ty = rhs.ty(local_decls, tcx);
                 let ty = op.ty(tcx, lhs_ty, rhs_ty);
-                tcx.intern_tup(&[ty, tcx.types.bool])
+                tcx.mk_tup(&[ty, tcx.types.bool])
             }
             Rvalue::UnaryOp(UnOp::Not | UnOp::Neg, ref operand) => operand.ty(local_decls, tcx),
             Rvalue::Discriminant(ref place) => place.ty(local_decls, tcx).ty.discriminant_ty(tcx),
             Rvalue::NullaryOp(NullOp::SizeOf | NullOp::AlignOf, _) => tcx.types.usize,
             Rvalue::Aggregate(ref ak, ref ops) => match **ak {
                 AggregateKind::Array(ty) => tcx.mk_array(ty, ops.len() as u64),
-                AggregateKind::Tuple => tcx.mk_tup(ops.iter().map(|op| op.ty(local_decls, tcx))),
+                AggregateKind::Tuple => {
+                    tcx.mk_tup_from_iter(ops.iter().map(|op| op.ty(local_decls, tcx)))
+                }
                 AggregateKind::Adt(did, _, substs, _, _) => tcx.type_of(did).subst(tcx, substs),
                 AggregateKind::Closure(did, substs) => tcx.mk_closure(did, substs),
                 AggregateKind::Generator(did, substs, movability) => {

compiler/rustc_middle/src/mir/type_foldable.rs

@@ -53,6 +53,6 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<PlaceElem<'tcx>> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_place_elems(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_place_elems(v))
     }
 }

compiler/rustc_middle/src/mir/visit.rs

@@ -1045,7 +1045,7 @@ macro_rules! visit_place_fns {
             self.visit_local(&mut place.local, context, location);
 
             if let Some(new_projection) = self.process_projection(&place.projection, location) {
-                place.projection = self.tcx().intern_place_elems(&new_projection);
+                place.projection = self.tcx().mk_place_elems(&new_projection);
             }
         }
 

compiler/rustc_middle/src/traits/solve.rs

@@ -30,20 +30,18 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for ExternalConstraints<'tcx> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        Ok(FallibleTypeFolder::interner(folder).intern_external_constraints(
+        Ok(FallibleTypeFolder::interner(folder).mk_external_constraints(ExternalConstraintsData {
-            ExternalConstraintsData {
+            regions: (),
-                regions: (),
+            opaque_types: self
-                opaque_types: self
+                .opaque_types
-                    .opaque_types
+                .iter()
-                    .iter()
+                .map(|opaque| opaque.try_fold_with(folder))
-                    .map(|opaque| opaque.try_fold_with(folder))
+                .collect::<Result<_, F::Error>>()?,
-                    .collect::<Result<_, F::Error>>()?,
+        }))
-            },
-        ))
     }
 
     fn fold_with<F: TypeFolder<TyCtxt<'tcx>>>(self, folder: &mut F) -> Self {
-        TypeFolder::interner(folder).intern_external_constraints(ExternalConstraintsData {
+        TypeFolder::interner(folder).mk_external_constraints(ExternalConstraintsData {
             regions: (),
             opaque_types: self.opaque_types.iter().map(|opaque| opaque.fold_with(folder)).collect(),
         })

compiler/rustc_middle/src/ty/adt.rs

@@ -54,7 +54,7 @@ bitflags! {
 
 /// The definition of a user-defined type, e.g., a `struct`, `enum`, or `union`.
 ///
-/// These are all interned (by `alloc_adt_def`) into the global arena.
+/// These are all interned (by `mk_adt_def`) into the global arena.
 ///
 /// The initialism *ADT* stands for an [*algebraic data type (ADT)*][adt].
 /// This is slightly wrong because `union`s are not ADTs.

compiler/rustc_middle/src/ty/codec.rs

@@ -244,7 +244,7 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for SubstsRef<'tcx> {
     fn decode(decoder: &mut D) -> Self {
         let len = decoder.read_usize();
         let tcx = decoder.interner();
-        tcx.mk_substs(
+        tcx.mk_substs_from_iter(
             (0..len).map::<ty::subst::GenericArg<'tcx>, _>(|_| Decodable::decode(decoder)),
         )
     }
@@ -254,7 +254,7 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for mir::Place<'tcx> {
     fn decode(decoder: &mut D) -> Self {
         let local: mir::Local = Decodable::decode(decoder);
         let len = decoder.read_usize();
-        let projection = decoder.interner().mk_place_elems(
+        let projection = decoder.interner().mk_place_elems_from_iter(
             (0..len).map::<mir::PlaceElem<'tcx>, _>(|_| Decodable::decode(decoder)),
         );
         mir::Place { local, projection }
@@ -272,7 +272,7 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for CanonicalVarInfos<'t
         let len = decoder.read_usize();
         let interned: Vec<CanonicalVarInfo<'tcx>> =
             (0..len).map(|_| Decodable::decode(decoder)).collect();
-        decoder.interner().intern_canonical_var_infos(interned.as_slice())
+        decoder.interner().mk_canonical_var_infos(&interned)
     }
 }
 
@@ -310,7 +310,9 @@ macro_rules! impl_decodable_via_ref {
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D> for ty::List<Ty<'tcx>> {
     fn decode(decoder: &mut D) -> &'tcx Self {
         let len = decoder.read_usize();
-        decoder.interner().mk_type_list((0..len).map::<Ty<'tcx>, _>(|_| Decodable::decode(decoder)))
+        decoder
+            .interner()
+            .mk_type_list_from_iter((0..len).map::<Ty<'tcx>, _>(|_| Decodable::decode(decoder)))
     }
 }
 
@@ -319,7 +321,7 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D>
 {
     fn decode(decoder: &mut D) -> &'tcx Self {
         let len = decoder.read_usize();
-        decoder.interner().mk_poly_existential_predicates(
+        decoder.interner().mk_poly_existential_predicates_from_iter(
             (0..len).map::<ty::Binder<'tcx, _>, _>(|_| Decodable::decode(decoder)),
         )
     }
@@ -342,13 +344,13 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D> for [ty::ValTre
 
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for ConstAllocation<'tcx> {
     fn decode(decoder: &mut D) -> Self {
-        decoder.interner().intern_const_alloc(Decodable::decode(decoder))
+        decoder.interner().mk_const_alloc(Decodable::decode(decoder))
     }
 }
 
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> Decodable<D> for AdtDef<'tcx> {
     fn decode(decoder: &mut D) -> Self {
-        decoder.interner().intern_adt_def(Decodable::decode(decoder))
+        decoder.interner().mk_adt_def_from_data(Decodable::decode(decoder))
     }
 }
 
@@ -375,7 +377,7 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D>
 {
     fn decode(decoder: &mut D) -> &'tcx Self {
         let len = decoder.read_usize();
-        decoder.interner().mk_bound_variable_kinds(
+        decoder.interner().mk_bound_variable_kinds_from_iter(
             (0..len).map::<ty::BoundVariableKind, _>(|_| Decodable::decode(decoder)),
         )
     }
@@ -384,18 +386,18 @@ impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D>
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D> for ty::List<ty::Const<'tcx>> {
     fn decode(decoder: &mut D) -> &'tcx Self {
         let len = decoder.read_usize();
-        decoder
+        decoder.interner().mk_const_list_from_iter(
-            .interner()
+            (0..len).map::<ty::Const<'tcx>, _>(|_| Decodable::decode(decoder)),
-            .mk_const_list((0..len).map::<ty::Const<'tcx>, _>(|_| Decodable::decode(decoder)))
+        )
     }
 }
 
 impl<'tcx, D: TyDecoder<I = TyCtxt<'tcx>>> RefDecodable<'tcx, D> for ty::List<ty::Predicate<'tcx>> {
     fn decode(decoder: &mut D) -> &'tcx Self {
         let len = decoder.read_usize();
-        let predicates: Vec<_> =
+        decoder.interner().mk_predicates_from_iter(
-            (0..len).map::<ty::Predicate<'tcx>, _>(|_| Decodable::decode(decoder)).collect();
+            (0..len).map::<ty::Predicate<'tcx>, _>(|_| Decodable::decode(decoder)),
-        decoder.interner().intern_predicates(&predicates)
+        )
     }
 }
 

compiler/rustc_middle/src/ty/context.rs

@@ -177,7 +177,7 @@ impl<'tcx> CtxtInterners<'tcx> {
         }
     }
 
-    /// Interns a type.
+    /// Interns a type. (Use `mk_*` functions instead, where possible.)
     #[allow(rustc::usage_of_ty_tykind)]
     #[inline(never)]
     fn intern_ty(&self, kind: TyKind<'tcx>, sess: &Session, untracked: &Untracked) -> Ty<'tcx> {
@@ -217,6 +217,7 @@ impl<'tcx> CtxtInterners<'tcx> {
         }
     }
 
+    /// Interns a predicate. (Use `mk_predicate` instead, where possible.)
     #[inline(never)]
     fn intern_predicate(
         &self,
@@ -615,21 +616,21 @@ impl<'tcx> TyCtxt<'tcx> {
         self.arena.alloc(Steal::new(promoted))
     }
 
-    pub fn alloc_adt_def(
+    pub fn mk_adt_def(
         self,
         did: DefId,
         kind: AdtKind,
         variants: IndexVec<VariantIdx, ty::VariantDef>,
         repr: ReprOptions,
     ) -> ty::AdtDef<'tcx> {
-        self.intern_adt_def(ty::AdtDefData::new(self, did, kind, variants, repr))
+        self.mk_adt_def_from_data(ty::AdtDefData::new(self, did, kind, variants, repr))
     }
 
     /// Allocates a read-only byte or string literal for `mir::interpret`.
     pub fn allocate_bytes(self, bytes: &[u8]) -> interpret::AllocId {
         // Create an allocation that just contains these bytes.
         let alloc = interpret::Allocation::from_bytes_byte_aligned_immutable(bytes);
-        let alloc = self.intern_const_alloc(alloc);
+        let alloc = self.mk_const_alloc(alloc);
         self.create_memory_alloc(alloc)
     }
 
@@ -1194,7 +1195,7 @@ impl<'tcx> TyCtxt<'tcx> {
         self.mk_imm_ref(
             self.lifetimes.re_static,
             self.type_of(self.require_lang_item(LangItem::PanicLocation, None))
-                .subst(self, self.intern_substs(&[self.lifetimes.re_static.into()])),
+                .subst(self, self.mk_substs(&[self.lifetimes.re_static.into()])),
         )
     }
 
@@ -1276,7 +1277,7 @@ macro_rules! nop_lift {
 
 // Can't use the macros as we have reuse the `substs` here.
 //
-// See `intern_type_list` for more info.
+// See `mk_type_list` for more info.
 impl<'a, 'tcx> Lift<'tcx> for &'a List<Ty<'a>> {
     type Lifted = &'tcx List<Ty<'tcx>>;
     fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<Self::Lifted> {
@@ -1517,7 +1518,7 @@ impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, List<T>> {
 }
 
 macro_rules! direct_interners {
-    ($($name:ident: $method:ident($ty:ty): $ret_ctor:ident -> $ret_ty:ty,)+) => {
+    ($($name:ident: $vis:vis $method:ident($ty:ty): $ret_ctor:ident -> $ret_ty:ty,)+) => {
         $(impl<'tcx> Borrow<$ty> for InternedInSet<'tcx, $ty> {
             fn borrow<'a>(&'a self) -> &'a $ty {
                 &self.0
@@ -1543,7 +1544,7 @@ macro_rules! direct_interners {
         }
 
         impl<'tcx> TyCtxt<'tcx> {
-            pub fn $method(self, v: $ty) -> $ret_ty {
+            $vis fn $method(self, v: $ty) -> $ret_ty {
                 $ret_ctor(Interned::new_unchecked(self.interners.$name.intern(v, |v| {
                     InternedInSet(self.interners.arena.alloc(v))
                 }).0))
@@ -1552,19 +1553,23 @@ macro_rules! direct_interners {
     }
 }
 
+// Functions with a `mk_` prefix are intended for use outside this file and
+// crate. Functions with an `intern_` prefix are intended for use within this
+// file only, and have a corresponding `mk_` function.
 direct_interners! {
     region: intern_region(RegionKind<'tcx>): Region -> Region<'tcx>,
-    const_: mk_const_internal(ConstData<'tcx>): Const -> Const<'tcx>,
+    const_: intern_const(ConstData<'tcx>): Const -> Const<'tcx>,
-    const_allocation: intern_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
+    const_allocation: pub mk_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
-    layout: intern_layout(LayoutS): Layout -> Layout<'tcx>,
+    layout: pub mk_layout(LayoutS): Layout -> Layout<'tcx>,
-    adt_def: intern_adt_def(AdtDefData): AdtDef -> AdtDef<'tcx>,
+    adt_def: pub mk_adt_def_from_data(AdtDefData): AdtDef -> AdtDef<'tcx>,
-    external_constraints: intern_external_constraints(ExternalConstraintsData<'tcx>): ExternalConstraints -> ExternalConstraints<'tcx>,
+    external_constraints: pub mk_external_constraints(ExternalConstraintsData<'tcx>):
+        ExternalConstraints -> ExternalConstraints<'tcx>,
 }
 
 macro_rules! slice_interners {
-    ($($field:ident: $method:ident($ty:ty)),+ $(,)?) => (
+    ($($field:ident: $vis:vis $method:ident($ty:ty)),+ $(,)?) => (
         impl<'tcx> TyCtxt<'tcx> {
-            $(pub fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
+            $($vis fn $method(self, v: &[$ty]) -> &'tcx List<$ty> {
                 if v.is_empty() {
                     List::empty()
                 } else {
@@ -1577,16 +1582,18 @@ macro_rules! slice_interners {
     );
 }
 
+// These functions intern slices. They all have a corresponding
+// `mk_foo_from_iter` function that interns an iterator. The slice version
+// should be used when possible, because it's faster.
 slice_interners!(
-    const_lists: intern_const_list(Const<'tcx>),
+    const_lists: pub mk_const_list(Const<'tcx>),
-    substs: intern_substs(GenericArg<'tcx>),
+    substs: pub mk_substs(GenericArg<'tcx>),
-    canonical_var_infos: intern_canonical_var_infos(CanonicalVarInfo<'tcx>),
+    canonical_var_infos: pub mk_canonical_var_infos(CanonicalVarInfo<'tcx>),
-    poly_existential_predicates:
+    poly_existential_predicates: intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
-        _intern_poly_existential_predicates(PolyExistentialPredicate<'tcx>),
+    predicates: intern_predicates(Predicate<'tcx>),
-    predicates: _intern_predicates(Predicate<'tcx>),
+    projs: pub mk_projs(ProjectionKind),
-    projs: intern_projs(ProjectionKind),
+    place_elems: pub mk_place_elems(PlaceElem<'tcx>),
-    place_elems: intern_place_elems(PlaceElem<'tcx>),
+    bound_variable_kinds: pub mk_bound_variable_kinds(ty::BoundVariableKind),
-    bound_variable_kinds: intern_bound_variable_kinds(ty::BoundVariableKind),
 );
 
 impl<'tcx> TyCtxt<'tcx> {
@@ -1834,16 +1841,16 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     #[inline]
-    pub fn intern_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
+    pub fn mk_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
-        if ts.is_empty() { self.types.unit } else { self.mk_ty(Tuple(self.intern_type_list(&ts))) }
+        if ts.is_empty() { self.types.unit } else { self.mk_ty(Tuple(self.mk_type_list(&ts))) }
     }
 
-    pub fn mk_tup<I, T>(self, iter: I) -> T::Output
+    pub fn mk_tup_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<Ty<'tcx>, Ty<'tcx>>,
     {
-        T::collect_and_apply(iter, |ts| self.intern_tup(ts))
+        T::collect_and_apply(iter, |ts| self.mk_tup(ts))
     }
 
     #[inline]
@@ -1862,12 +1869,12 @@ impl<'tcx> TyCtxt<'tcx> {
         def_id: DefId,
         substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
     ) -> Ty<'tcx> {
-        let substs = self.check_substs(def_id, substs);
+        let substs = self.check_and_mk_substs(def_id, substs);
         self.mk_ty(FnDef(def_id, substs))
     }
 
     #[inline(always)]
-    fn check_substs(
+    fn check_and_mk_substs(
         self,
         _def_id: DefId,
         substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
@@ -1883,7 +1890,7 @@ impl<'tcx> TyCtxt<'tcx> {
                 substs.collect::<Vec<_>>(),
             );
         }
-        self.mk_substs(substs)
+        self.mk_substs_from_iter(substs)
     }
 
     #[inline]
@@ -1934,7 +1941,7 @@ impl<'tcx> TyCtxt<'tcx> {
     pub fn mk_task_context(self) -> Ty<'tcx> {
         let context_did = self.require_lang_item(LangItem::Context, None);
         let context_adt_ref = self.adt_def(context_did);
-        let context_substs = self.intern_substs(&[self.lifetimes.re_erased.into()]);
+        let context_substs = self.mk_substs(&[self.lifetimes.re_erased.into()]);
         let context_ty = self.mk_adt(context_adt_ref, context_substs);
         self.mk_mut_ref(self.lifetimes.re_erased, context_ty)
     }
@@ -1946,7 +1953,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     #[inline]
     pub fn mk_const(self, kind: impl Into<ty::ConstKind<'tcx>>, ty: Ty<'tcx>) -> Const<'tcx> {
-        self.mk_const_internal(ty::ConstData { kind: kind.into(), ty })
+        self.intern_const(ty::ConstData { kind: kind.into(), ty })
     }
 
     #[inline]
@@ -2136,10 +2143,10 @@ impl<'tcx> TyCtxt<'tcx> {
         let mut projection = place.projection.to_vec();
         projection.push(elem);
 
-        Place { local: place.local, projection: self.intern_place_elems(&projection) }
+        Place { local: place.local, projection: self.mk_place_elems(&projection) }
     }
 
-    pub fn intern_poly_existential_predicates(
+    pub fn mk_poly_existential_predicates(
         self,
         eps: &[PolyExistentialPredicate<'tcx>],
     ) -> &'tcx List<PolyExistentialPredicate<'tcx>> {
@@ -2149,25 +2156,25 @@ impl<'tcx> TyCtxt<'tcx> {
                 .all(|[a, b]| a.skip_binder().stable_cmp(self, &b.skip_binder())
                     != Ordering::Greater)
         );
-        self._intern_poly_existential_predicates(eps)
+        self.intern_poly_existential_predicates(eps)
     }
 
-    pub fn intern_predicates(self, preds: &[Predicate<'tcx>]) -> &'tcx List<Predicate<'tcx>> {
+    pub fn mk_predicates(self, preds: &[Predicate<'tcx>]) -> &'tcx List<Predicate<'tcx>> {
         // FIXME consider asking the input slice to be sorted to avoid
         // re-interning permutations, in which case that would be asserted
         // here.
-        self._intern_predicates(preds)
+        self.intern_predicates(preds)
     }
 
-    pub fn mk_const_list<I, T>(self, iter: I) -> T::Output
+    pub fn mk_const_list_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<ty::Const<'tcx>, &'tcx List<ty::Const<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_const_list(xs))
+        T::collect_and_apply(iter, |xs| self.mk_const_list(xs))
     }
 
-    pub fn intern_type_list(self, ts: &[Ty<'tcx>]) -> &'tcx List<Ty<'tcx>> {
+    pub fn mk_type_list(self, ts: &[Ty<'tcx>]) -> &'tcx List<Ty<'tcx>> {
         // Actually intern type lists as lists of `GenericArg`s.
         //
         // Transmuting from `Ty<'tcx>` to `GenericArg<'tcx>` is sound
@@ -2175,15 +2182,14 @@ impl<'tcx> TyCtxt<'tcx> {
         // we guarantee that even when transmuting between `List<Ty<'tcx>>`
         // and `List<GenericArg<'tcx>>`, the uniqueness requirement for
         // lists is upheld.
-        let substs = self.intern_substs(ty::subst::ty_slice_as_generic_args(ts));
+        let substs = self.mk_substs(ty::subst::ty_slice_as_generic_args(ts));
         substs.try_as_type_list().unwrap()
     }
 
-    // Unlike various other `mk_*` functions, this one uses `I: IntoIterator`
+    // Unlike various other `mk_*_from_iter` functions, this one uses `I:
-    // instead of `I: Iterator`. Unlike those other functions, this one doesn't
+    // IntoIterator` instead of `I: Iterator`, and it doesn't have a slice
-    // have a `intern_fn_sig` variant that can be used for cases where `I` is
+    // variant, because of the need to combine `inputs` and `output`. This
-    // something like a `Vec`. That's because of the need to combine `inputs`
+    // explains the lack of `_from_iter` suffix.
-    // and `output`.
     pub fn mk_fn_sig<I, T>(
         self,
         inputs: I,
@@ -2197,14 +2203,14 @@ impl<'tcx> TyCtxt<'tcx> {
         T: CollectAndApply<Ty<'tcx>, ty::FnSig<'tcx>>,
     {
         T::collect_and_apply(inputs.into_iter().chain(iter::once(output)), |xs| ty::FnSig {
-            inputs_and_output: self.intern_type_list(xs),
+            inputs_and_output: self.mk_type_list(xs),
             c_variadic,
             unsafety,
             abi,
         })
     }
 
-    pub fn mk_poly_existential_predicates<I, T>(self, iter: I) -> T::Output
+    pub fn mk_poly_existential_predicates_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<
@@ -2212,39 +2218,39 @@ impl<'tcx> TyCtxt<'tcx> {
                 &'tcx List<PolyExistentialPredicate<'tcx>>,
             >,
     {
-        T::collect_and_apply(iter, |xs| self.intern_poly_existential_predicates(xs))
+        T::collect_and_apply(iter, |xs| self.mk_poly_existential_predicates(xs))
     }
 
-    pub fn mk_predicates<I, T>(self, iter: I) -> T::Output
+    pub fn mk_predicates_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<Predicate<'tcx>, &'tcx List<Predicate<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_predicates(xs))
+        T::collect_and_apply(iter, |xs| self.mk_predicates(xs))
     }
 
-    pub fn mk_type_list<I, T>(self, iter: I) -> T::Output
+    pub fn mk_type_list_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<Ty<'tcx>, &'tcx List<Ty<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_type_list(xs))
+        T::collect_and_apply(iter, |xs| self.mk_type_list(xs))
     }
 
-    pub fn mk_substs<I, T>(self, iter: I) -> T::Output
+    pub fn mk_substs_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<GenericArg<'tcx>, &'tcx List<GenericArg<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_substs(xs))
+        T::collect_and_apply(iter, |xs| self.mk_substs(xs))
     }
 
-    pub fn mk_place_elems<I, T>(self, iter: I) -> T::Output
+    pub fn mk_place_elems_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<PlaceElem<'tcx>, &'tcx List<PlaceElem<'tcx>>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_place_elems(xs))
+        T::collect_and_apply(iter, |xs| self.mk_place_elems(xs))
     }
 
     pub fn mk_substs_trait(
@@ -2252,7 +2258,7 @@ impl<'tcx> TyCtxt<'tcx> {
         self_ty: Ty<'tcx>,
         rest: impl IntoIterator<Item = GenericArg<'tcx>>,
     ) -> SubstsRef<'tcx> {
-        self.mk_substs(iter::once(self_ty.into()).chain(rest))
+        self.mk_substs_from_iter(iter::once(self_ty.into()).chain(rest))
     }
 
     pub fn mk_trait_ref(
@@ -2260,7 +2266,7 @@ impl<'tcx> TyCtxt<'tcx> {
         trait_def_id: DefId,
         substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
     ) -> ty::TraitRef<'tcx> {
-        let substs = self.check_substs(trait_def_id, substs);
+        let substs = self.check_and_mk_substs(trait_def_id, substs);
         ty::TraitRef { def_id: trait_def_id, substs, _use_mk_trait_ref_instead: () }
     }
 
@@ -2269,16 +2275,16 @@ impl<'tcx> TyCtxt<'tcx> {
         def_id: DefId,
         substs: impl IntoIterator<Item: Into<GenericArg<'tcx>>>,
     ) -> ty::AliasTy<'tcx> {
-        let substs = self.check_substs(def_id, substs);
+        let substs = self.check_and_mk_substs(def_id, substs);
         ty::AliasTy { def_id, substs, _use_mk_alias_ty_instead: () }
     }
 
-    pub fn mk_bound_variable_kinds<I, T>(self, iter: I) -> T::Output
+    pub fn mk_bound_variable_kinds_from_iter<I, T>(self, iter: I) -> T::Output
     where
         I: Iterator<Item = T>,
         T: CollectAndApply<ty::BoundVariableKind, &'tcx List<ty::BoundVariableKind>>,
     {
-        T::collect_and_apply(iter, |xs| self.intern_bound_variable_kinds(xs))
+        T::collect_and_apply(iter, |xs| self.mk_bound_variable_kinds(xs))
     }
 
     /// Emit a lint at `span` from a lint struct (some type that implements `DecorateLint`,
@@ -2363,7 +2369,7 @@ impl<'tcx> TyCtxt<'tcx> {
     }
 
     pub fn late_bound_vars(self, id: HirId) -> &'tcx List<ty::BoundVariableKind> {
-        self.intern_bound_variable_kinds(
+        self.mk_bound_variable_kinds(
             &self
                 .late_bound_vars_map(id.owner)
                 .and_then(|map| map.get(&id.local_id).cloned())

compiler/rustc_middle/src/ty/fold.rs

@@ -422,7 +422,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let mut map = Default::default();
         let delegate = Anonymize { tcx: self, map: &mut map };
         let inner = self.replace_escaping_bound_vars_uncached(value.skip_binder(), delegate);
-        let bound_vars = self.mk_bound_variable_kinds(map.into_values());
+        let bound_vars = self.mk_bound_variable_kinds_from_iter(map.into_values());
         Binder::bind_with_vars(inner, bound_vars)
     }
 }

compiler/rustc_middle/src/ty/impls_ty.rs

@@ -79,7 +79,7 @@ impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ty::subst::GenericArgKin
             // WARNING: We dedup cache the `HashStable` results for `List`
             // while ignoring types and freely transmute
             // between `List<Ty<'tcx>>` and `List<GenericArg<'tcx>>`.
-            // See `fn intern_type_list` for more details.
+            // See `fn mk_type_list` for more details.
             //
             // We therefore hash types without adding a hash for their discriminant.
             //

compiler/rustc_middle/src/ty/instance.rs

@@ -540,7 +540,7 @@ impl<'tcx> Instance<'tcx> {
 
     pub fn resolve_drop_in_place(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ty::Instance<'tcx> {
         let def_id = tcx.require_lang_item(LangItem::DropInPlace, None);
-        let substs = tcx.intern_substs(&[ty.into()]);
+        let substs = tcx.mk_substs(&[ty.into()]);
         Instance::expect_resolve(tcx, ty::ParamEnv::reveal_all(), def_id, substs)
     }
 

compiler/rustc_middle/src/ty/layout.rs

@@ -596,7 +596,7 @@ where
                     ty::Adt(def, _) => def.variant(variant_index).fields.len(),
                     _ => bug!(),
                 };
-                tcx.intern_layout(LayoutS {
+                tcx.mk_layout(LayoutS {
                     variants: Variants::Single { index: variant_index },
                     fields: match NonZeroUsize::new(fields) {
                         Some(fields) => FieldsShape::Union(fields),
@@ -609,7 +609,7 @@ where
                 })
             }
 
-            Variants::Multiple { ref variants, .. } => cx.tcx().intern_layout(variants[variant_index].clone()),
+            Variants::Multiple { ref variants, .. } => cx.tcx().mk_layout(variants[variant_index].clone()),
         };
 
         assert_eq!(*layout.variants(), Variants::Single { index: variant_index });
@@ -631,7 +631,7 @@ where
             let tcx = cx.tcx();
             let tag_layout = |tag: Scalar| -> TyAndLayout<'tcx> {
                 TyAndLayout {
-                    layout: tcx.intern_layout(LayoutS::scalar(cx, tag)),
+                    layout: tcx.mk_layout(LayoutS::scalar(cx, tag)),
                     ty: tag.primitive().to_ty(tcx),
                 }
             };
@@ -687,7 +687,7 @@ where
                         Increase this counter if you tried to implement this but
                         failed to do it without duplicating a lot of code from
                         other places in the compiler: 2
-                        tcx.intern_tup(&[
+                        tcx.mk_tup(&[
                             tcx.mk_array(tcx.types.usize, 3),
                             tcx.mk_array(Option<fn()>),
                         ])

compiler/rustc_middle/src/ty/mod.rs

@@ -757,7 +757,7 @@ impl<'tcx> Predicate<'tcx> {
         let new = EarlyBinder(shifted_pred).subst(tcx, trait_ref.skip_binder().substs);
         // 3) ['x] + ['b] -> ['x, 'b]
         let bound_vars =
-            tcx.mk_bound_variable_kinds(trait_bound_vars.iter().chain(pred_bound_vars));
+            tcx.mk_bound_variable_kinds_from_iter(trait_bound_vars.iter().chain(pred_bound_vars));
         tcx.reuse_or_mk_predicate(self, ty::Binder::bind_with_vars(new, bound_vars))
     }
 }

compiler/rustc_middle/src/ty/opaque_types.rs

@@ -79,7 +79,7 @@ impl<'tcx> ReverseMapper<'tcx> {
         // during codegen.
 
         let generics = self.tcx.generics_of(def_id);
-        self.tcx.mk_substs(substs.iter().enumerate().map(|(index, kind)| {
+        self.tcx.mk_substs_from_iter(substs.iter().enumerate().map(|(index, kind)| {
             if index < generics.parent_count {
                 // Accommodate missing regions in the parent kinds...
                 self.fold_kind_no_missing_regions_error(kind)

compiler/rustc_middle/src/ty/relate.rs

@@ -144,7 +144,7 @@ pub fn relate_substs<'tcx, R: TypeRelation<'tcx>>(
     a_subst: SubstsRef<'tcx>,
     b_subst: SubstsRef<'tcx>,
 ) -> RelateResult<'tcx, SubstsRef<'tcx>> {
-    relation.tcx().mk_substs(iter::zip(a_subst, b_subst).map(|(a, b)| {
+    relation.tcx().mk_substs_from_iter(iter::zip(a_subst, b_subst).map(|(a, b)| {
         relation.relate_with_variance(ty::Invariant, ty::VarianceDiagInfo::default(), a, b)
     }))
 }
@@ -171,7 +171,7 @@ pub fn relate_substs_with_variances<'tcx, R: TypeRelation<'tcx>>(
         relation.relate_with_variance(variance, variance_info, a, b)
     });
 
-    tcx.mk_substs(params)
+    tcx.mk_substs_from_iter(params)
 }
 
 impl<'tcx> Relate<'tcx> for ty::FnSig<'tcx> {
@@ -222,7 +222,7 @@ impl<'tcx> Relate<'tcx> for ty::FnSig<'tcx> {
                 r => r,
             });
         Ok(ty::FnSig {
-            inputs_and_output: tcx.mk_type_list(inputs_and_output)?,
+            inputs_and_output: tcx.mk_type_list_from_iter(inputs_and_output)?,
             c_variadic: a.c_variadic,
             unsafety,
             abi,
@@ -352,7 +352,8 @@ impl<'tcx> Relate<'tcx> for GeneratorWitness<'tcx> {
     ) -> RelateResult<'tcx, GeneratorWitness<'tcx>> {
         assert_eq!(a.0.len(), b.0.len());
         let tcx = relation.tcx();
-        let types = tcx.mk_type_list(iter::zip(a.0, b.0).map(|(a, b)| relation.relate(a, b)))?;
+        let types =
+            tcx.mk_type_list_from_iter(iter::zip(a.0, b.0).map(|(a, b)| relation.relate(a, b)))?;
         Ok(GeneratorWitness(types))
     }
 }
@@ -528,7 +529,7 @@ pub fn super_relate_tys<'tcx, R: TypeRelation<'tcx>>(
 
         (&ty::Tuple(as_), &ty::Tuple(bs)) => {
             if as_.len() == bs.len() {
-                Ok(tcx.mk_tup(iter::zip(as_, bs).map(|(a, b)| relation.relate(a, b)))?)
+                Ok(tcx.mk_tup_from_iter(iter::zip(as_, bs).map(|(a, b)| relation.relate(a, b)))?)
             } else if !(as_.is_empty() || bs.is_empty()) {
                 Err(TypeError::TupleSize(expected_found(relation, as_.len(), bs.len())))
             } else {
@@ -673,7 +674,7 @@ pub fn super_relate_consts<'tcx, R: TypeRelation<'tcx>>(
                     for (a_arg, b_arg) in aa.iter().zip(ba.iter()) {
                         related_args.push(r.consts(a_arg, b_arg)?);
                     }
-                    let related_args = tcx.intern_const_list(&related_args);
+                    let related_args = tcx.mk_const_list(&related_args);
                     Expr::FunctionCall(func, related_args)
                 }
                 _ => return Err(TypeError::ConstMismatch(expected_found(r, a, b))),
@@ -720,7 +721,7 @@ impl<'tcx> Relate<'tcx> for &'tcx ty::List<ty::PolyExistentialPredicate<'tcx>> {
                 _ => Err(TypeError::ExistentialMismatch(expected_found(relation, a, b))),
             }
         });
-        tcx.mk_poly_existential_predicates(v)
+        tcx.mk_poly_existential_predicates_from_iter(v)
     }
 }
 

compiler/rustc_middle/src/ty/structural_impls.rs

@@ -430,7 +430,7 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<ty::PolyExistentialPred
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_poly_existential_predicates(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_poly_existential_predicates(v))
     }
 }
 
@@ -439,7 +439,7 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<ty::Const<'tcx>> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_const_list(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_const_list(v))
     }
 }
 
@@ -448,7 +448,7 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<ProjectionKind> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_projs(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_projs(v))
     }
 }
 
@@ -636,7 +636,7 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<ty::Predicate<'tcx>> {
         self,
         folder: &mut F,
     ) -> Result<Self, F::Error> {
-        ty::util::fold_list(self, folder, |tcx, v| tcx.intern_predicates(v))
+        ty::util::fold_list(self, folder, |tcx, v| tcx.mk_predicates(v))
     }
 }
 

compiler/rustc_middle/src/ty/sty.rs

@@ -250,7 +250,7 @@ impl<'tcx> ClosureSubsts<'tcx> {
         parts: ClosureSubstsParts<'tcx, Ty<'tcx>>,
     ) -> ClosureSubsts<'tcx> {
         ClosureSubsts {
-            substs: tcx.mk_substs(
+            substs: tcx.mk_substs_from_iter(
                 parts.parent_substs.iter().copied().chain(
                     [parts.closure_kind_ty, parts.closure_sig_as_fn_ptr_ty, parts.tupled_upvars_ty]
                         .iter()
@@ -377,7 +377,7 @@ impl<'tcx> GeneratorSubsts<'tcx> {
         parts: GeneratorSubstsParts<'tcx, Ty<'tcx>>,
     ) -> GeneratorSubsts<'tcx> {
         GeneratorSubsts {
-            substs: tcx.mk_substs(
+            substs: tcx.mk_substs_from_iter(
                 parts.parent_substs.iter().copied().chain(
                     [
                         parts.resume_ty,
@@ -655,7 +655,7 @@ impl<'tcx> InlineConstSubsts<'tcx> {
         parts: InlineConstSubstsParts<'tcx, Ty<'tcx>>,
     ) -> InlineConstSubsts<'tcx> {
         InlineConstSubsts {
-            substs: tcx.mk_substs(
+            substs: tcx.mk_substs_from_iter(
                 parts.parent_substs.iter().copied().chain(std::iter::once(parts.ty.into())),
             ),
         }
@@ -853,7 +853,7 @@ impl<'tcx> TraitRef<'tcx> {
         substs: SubstsRef<'tcx>,
     ) -> ty::TraitRef<'tcx> {
         let defs = tcx.generics_of(trait_id);
-        tcx.mk_trait_ref(trait_id, tcx.intern_substs(&substs[..defs.params.len()]))
+        tcx.mk_trait_ref(trait_id, tcx.mk_substs(&substs[..defs.params.len()]))
     }
 }
 
@@ -899,7 +899,7 @@ impl<'tcx> ExistentialTraitRef<'tcx> {
 
         ty::ExistentialTraitRef {
             def_id: trait_ref.def_id,
-            substs: tcx.intern_substs(&trait_ref.substs[1..]),
+            substs: tcx.mk_substs(&trait_ref.substs[1..]),
         }
     }
 
@@ -1551,7 +1551,7 @@ impl<'tcx> ExistentialProjection<'tcx> {
     pub fn trait_ref(&self, tcx: TyCtxt<'tcx>) -> ty::ExistentialTraitRef<'tcx> {
         let def_id = tcx.parent(self.def_id);
         let subst_count = tcx.generics_of(def_id).count() - 1;
-        let substs = tcx.intern_substs(&self.substs[..subst_count]);
+        let substs = tcx.mk_substs(&self.substs[..subst_count]);
         ty::ExistentialTraitRef { def_id, substs }
     }
 
@@ -1579,7 +1579,7 @@ impl<'tcx> ExistentialProjection<'tcx> {
 
         Self {
             def_id: projection_predicate.projection_ty.def_id,
-            substs: tcx.intern_substs(&projection_predicate.projection_ty.substs[1..]),
+            substs: tcx.mk_substs(&projection_predicate.projection_ty.substs[1..]),
             term: projection_predicate.term,
         }
     }
@@ -2209,7 +2209,7 @@ impl<'tcx> Ty<'tcx> {
                 let assoc_items = tcx.associated_item_def_ids(
                     tcx.require_lang_item(hir::LangItem::DiscriminantKind, None),
                 );
-                tcx.mk_projection(assoc_items[0], tcx.intern_substs(&[self.into()]))
+                tcx.mk_projection(assoc_items[0], tcx.mk_substs(&[self.into()]))
             }
 
             ty::Bool

compiler/rustc_middle/src/ty/subst.rs

@@ -71,7 +71,7 @@ impl<'tcx> List<Ty<'tcx>> {
     /// Allows to freely switch between `List<Ty<'tcx>>` and `List<GenericArg<'tcx>>`.
     ///
     /// As lists are interned, `List<Ty<'tcx>>` and `List<GenericArg<'tcx>>` have
-    /// be interned together, see `intern_type_list` for more details.
+    /// be interned together, see `mk_type_list` for more details.
     #[inline]
     pub fn as_substs(&'tcx self) -> SubstsRef<'tcx> {
         assert_eq!(TYPE_TAG, 0);
@@ -319,7 +319,7 @@ impl<'tcx> InternalSubsts<'tcx> {
         let count = defs.count();
         let mut substs = SmallVec::with_capacity(count);
         Self::fill_item(&mut substs, tcx, defs, &mut mk_kind);
-        tcx.intern_substs(&substs)
+        tcx.mk_substs(&substs)
     }
 
     pub fn extend_to<F>(&self, tcx: TyCtxt<'tcx>, def_id: DefId, mut mk_kind: F) -> SubstsRef<'tcx>
@@ -468,11 +468,11 @@ impl<'tcx> InternalSubsts<'tcx> {
         target_substs: SubstsRef<'tcx>,
     ) -> SubstsRef<'tcx> {
         let defs = tcx.generics_of(source_ancestor);
-        tcx.mk_substs(target_substs.iter().chain(self.iter().skip(defs.params.len())))
+        tcx.mk_substs_from_iter(target_substs.iter().chain(self.iter().skip(defs.params.len())))
     }
 
     pub fn truncate_to(&self, tcx: TyCtxt<'tcx>, generics: &ty::Generics) -> SubstsRef<'tcx> {
-        tcx.mk_substs(self.iter().take(generics.count()))
+        tcx.mk_substs_from_iter(self.iter().take(generics.count()))
     }
 }
 
@@ -486,14 +486,14 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for SubstsRef<'tcx> {
         // The match arms are in order of frequency. The 1, 2, and 0 cases are
         // typically hit in 90--99.99% of cases. When folding doesn't change
         // the substs, it's faster to reuse the existing substs rather than
-        // calling `intern_substs`.
+        // calling `mk_substs`.
         match self.len() {
             1 => {
                 let param0 = self[0].try_fold_with(folder)?;
                 if param0 == self[0] {
                     Ok(self)
                 } else {
-                    Ok(folder.interner().intern_substs(&[param0]))
+                    Ok(folder.interner().mk_substs(&[param0]))
                 }
             }
             2 => {
@@ -502,11 +502,11 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for SubstsRef<'tcx> {
                 if param0 == self[0] && param1 == self[1] {
                     Ok(self)
                 } else {
-                    Ok(folder.interner().intern_substs(&[param0, param1]))
+                    Ok(folder.interner().mk_substs(&[param0, param1]))
                 }
             }
             0 => Ok(self),
-            _ => ty::util::fold_list(self, folder, |tcx, v| tcx.intern_substs(v)),
+            _ => ty::util::fold_list(self, folder, |tcx, v| tcx.mk_substs(v)),
         }
     }
 }
@@ -538,10 +538,10 @@ impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for &'tcx ty::List<Ty<'tcx>> {
                 if param0 == self[0] && param1 == self[1] {
                     Ok(self)
                 } else {
-                    Ok(folder.interner().intern_type_list(&[param0, param1]))
+                    Ok(folder.interner().mk_type_list(&[param0, param1]))
                 }
             }
-            _ => ty::util::fold_list(self, folder, |tcx, v| tcx.intern_type_list(v)),
+            _ => ty::util::fold_list(self, folder, |tcx, v| tcx.mk_type_list(v)),
         }
     }
 }

compiler/rustc_middle/src/ty/vtable.rs

@@ -112,5 +112,5 @@ pub(super) fn vtable_allocation_provider<'tcx>(
     }
 
     vtable.mutability = Mutability::Not;
-    tcx.create_memory_alloc(tcx.intern_const_alloc(vtable))
+    tcx.create_memory_alloc(tcx.mk_const_alloc(vtable))
 }

compiler/rustc_mir_build/src/build/expr/as_constant.rs

@@ -132,14 +132,14 @@ pub(crate) fn lit_to_mir_constant<'tcx>(
         (ast::LitKind::Str(s, _), ty::Ref(_, inner_ty, _)) if inner_ty.is_str() => {
             let s = s.as_str();
             let allocation = Allocation::from_bytes_byte_aligned_immutable(s.as_bytes());
-            let allocation = tcx.intern_const_alloc(allocation);
+            let allocation = tcx.mk_const_alloc(allocation);
             ConstValue::Slice { data: allocation, start: 0, end: s.len() }
         }
         (ast::LitKind::ByteStr(data, _), ty::Ref(_, inner_ty, _))
             if matches!(inner_ty.kind(), ty::Slice(_)) =>
         {
             let allocation = Allocation::from_bytes_byte_aligned_immutable(data as &[u8]);
-            let allocation = tcx.intern_const_alloc(allocation);
+            let allocation = tcx.mk_const_alloc(allocation);
             ConstValue::Slice { data: allocation, start: 0, end: data.len() }
         }
         (ast::LitKind::ByteStr(data, _), ty::Ref(_, inner_ty, _)) if inner_ty.is_array() => {

compiler/rustc_mir_build/src/build/expr/as_operand.rs

@@ -170,7 +170,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     // Return the operand *tmp0 to be used as the call argument
                     let place = Place {
                         local: operand,
-                        projection: tcx.intern_place_elems(&[PlaceElem::Deref]),
+                        projection: tcx.mk_place_elems(&[PlaceElem::Deref]),
                     };
 
                     return block.and(Operand::Move(place));

compiler/rustc_mir_build/src/build/expr/as_place.rs

@@ -263,7 +263,7 @@ impl<'tcx> PlaceBuilder<'tcx> {
         let resolved = self.resolve_upvar(cx);
         let builder = resolved.as_ref().unwrap_or(self);
         let PlaceBase::Local(local) = builder.base else { return None };
-        let projection = cx.tcx.intern_place_elems(&builder.projection);
+        let projection = cx.tcx.mk_place_elems(&builder.projection);
         Some(Place { local, projection })
     }
 
@@ -692,7 +692,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                             tcx.mk_imm_ref(tcx.lifetimes.re_erased, fake_borrow_deref_ty);
                         let fake_borrow_temp =
                             self.local_decls.push(LocalDecl::new(fake_borrow_ty, expr_span));
-                        let projection = tcx.intern_place_elems(&base_place.projection[..idx]);
+                        let projection = tcx.mk_place_elems(&base_place.projection[..idx]);
                         self.cfg.push_assign(
                             block,
                             source_info,

compiler/rustc_mir_build/src/build/expr/as_rvalue.rs

@@ -520,7 +520,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         let source_info = self.source_info(span);
         let bool_ty = self.tcx.types.bool;
         if self.check_overflow && op.is_checkable() && ty.is_integral() {
-            let result_tup = self.tcx.intern_tup(&[ty, bool_ty]);
+            let result_tup = self.tcx.mk_tup(&[ty, bool_ty]);
             let result_value = self.temp(result_tup, span);
 
             self.cfg.push_assign(

compiler/rustc_mir_build/src/build/matches/mod.rs

@@ -1206,7 +1206,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
                     fake_borrows.insert(Place {
                         local: source.local,
-                        projection: self.tcx.intern_place_elems(proj_base),
+                        projection: self.tcx.mk_place_elems(proj_base),
                     });
                 }
             }
@@ -1743,7 +1743,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             .map(|matched_place_ref| {
                 let matched_place = Place {
                     local: matched_place_ref.local,
-                    projection: tcx.intern_place_elems(matched_place_ref.projection),
+                    projection: tcx.mk_place_elems(matched_place_ref.projection),
                 };
                 let fake_borrow_deref_ty = matched_place.ty(&self.local_decls, tcx).ty;
                 let fake_borrow_ty = tcx.mk_imm_ref(tcx.lifetimes.re_erased, fake_borrow_deref_ty);

compiler/rustc_mir_build/src/build/mod.rs

@@ -859,7 +859,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
                     let use_place = Place {
                         local: ty::CAPTURE_STRUCT_LOCAL,
-                        projection: tcx.intern_place_elems(&projs),
+                        projection: tcx.mk_place_elems(&projs),
                     };
                     self.var_debug_info.push(VarDebugInfo {
                         name: *sym,

compiler/rustc_mir_build/src/thir/cx/expr.rs

@@ -307,7 +307,7 @@ impl<'tcx> Cx<'tcx> {
 
                     let arg_tys = args.iter().map(|e| self.typeck_results().expr_ty_adjusted(e));
                     let tupled_args = Expr {
-                        ty: tcx.mk_tup(arg_tys),
+                        ty: tcx.mk_tup_from_iter(arg_tys),
                         temp_lifetime,
                         span: expr.span,
                         kind: ExprKind::Tuple { fields: self.mirror_exprs(args) },

compiler/rustc_mir_build/src/thir/cx/mod.rs

@@ -133,9 +133,8 @@ impl<'tcx> Cx<'tcx> {
                     bug!("closure expr does not have closure type: {:?}", closure_ty);
                 };
 
-                let bound_vars = self
+                let bound_vars =
-                    .tcx
+                    self.tcx.mk_bound_variable_kinds(&[ty::BoundVariableKind::Region(ty::BrEnv)]);
-                    .intern_bound_variable_kinds(&[ty::BoundVariableKind::Region(ty::BrEnv)]);
                 let br = ty::BoundRegion {
                     var: ty::BoundVar::from_usize(bound_vars.len() - 1),
                     kind: ty::BrEnv,

compiler/rustc_mir_dataflow/src/move_paths/builder.rs

@@ -126,7 +126,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
                         BorrowedContent {
                             target_place: Place {
                                 local: place.local,
-                                projection: tcx.intern_place_elems(proj),
+                                projection: tcx.mk_place_elems(proj),
                             },
                         },
                     ));
@@ -165,7 +165,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
             if union_path.is_none() {
                 base = self.add_move_path(base, elem, |tcx| Place {
                     local: place.local,
-                    projection: tcx.intern_place_elems(&place.projection[..i + 1]),
+                    projection: tcx.mk_place_elems(&place.projection[..i + 1]),
                 });
             }
         }
@@ -476,7 +476,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
             // `ConstIndex` patterns. This is done to ensure that all move paths
             // are disjoint, which is expected by drop elaboration.
             let base_place =
-                Place { local: place.local, projection: self.builder.tcx.intern_place_elems(base) };
+                Place { local: place.local, projection: self.builder.tcx.mk_place_elems(base) };
             let base_path = match self.move_path_for(base_place) {
                 Ok(path) => path,
                 Err(MoveError::UnionMove { path }) => {

compiler/rustc_mir_transform/src/copy_prop.rs

@@ -124,7 +124,7 @@ impl<'tcx> MutVisitor<'tcx> for Replacer<'_, 'tcx> {
 
     fn visit_place(&mut self, place: &mut Place<'tcx>, ctxt: PlaceContext, loc: Location) {
         if let Some(new_projection) = self.process_projection(&place.projection, loc) {
-            place.projection = self.tcx().intern_place_elems(&new_projection);
+            place.projection = self.tcx().mk_place_elems(&new_projection);
         }
 
         let observes_address = match ctxt {

compiler/rustc_mir_transform/src/elaborate_box_derefs.rs

@@ -17,7 +17,7 @@ pub fn build_ptr_tys<'tcx>(
     unique_did: DefId,
     nonnull_did: DefId,
 ) -> (Ty<'tcx>, Ty<'tcx>, Ty<'tcx>) {
-    let substs = tcx.intern_substs(&[pointee.into()]);
+    let substs = tcx.mk_substs(&[pointee.into()]);
     let unique_ty = tcx.type_of(unique_did).subst(tcx, substs);
     let nonnull_ty = tcx.type_of(nonnull_did).subst(tcx, substs);
     let ptr_ty = tcx.mk_imm_ptr(pointee);
@@ -138,7 +138,7 @@ impl<'tcx> MirPass<'tcx> for ElaborateBoxDerefs {
 
                     if let Some(mut new_projections) = new_projections {
                         new_projections.extend_from_slice(&place.projection[last_deref..]);
-                        place.projection = tcx.intern_place_elems(&new_projections);
+                        place.projection = tcx.mk_place_elems(&new_projections);
                     }
                 }
             }

compiler/rustc_mir_transform/src/generator.rs

@@ -126,7 +126,7 @@ impl<'tcx> MutVisitor<'tcx> for DerefArgVisitor<'tcx> {
                 place,
                 Place {
                     local: SELF_ARG,
-                    projection: self.tcx().intern_place_elems(&[ProjectionElem::Deref]),
+                    projection: self.tcx().mk_place_elems(&[ProjectionElem::Deref]),
                 },
                 self.tcx,
             );
@@ -162,10 +162,9 @@ impl<'tcx> MutVisitor<'tcx> for PinArgVisitor<'tcx> {
                 place,
                 Place {
                     local: SELF_ARG,
-                    projection: self.tcx().intern_place_elems(&[ProjectionElem::Field(
+                    projection: self
-                        Field::new(0),
+                        .tcx()
-                        self.ref_gen_ty,
+                        .mk_place_elems(&[ProjectionElem::Field(Field::new(0), self.ref_gen_ty)]),
-                    )]),
                 },
                 self.tcx,
             );
@@ -187,7 +186,7 @@ fn replace_base<'tcx>(place: &mut Place<'tcx>, new_base: Place<'tcx>, tcx: TyCtx
     let mut new_projection = new_base.projection.to_vec();
     new_projection.append(&mut place.projection.to_vec());
 
-    place.projection = tcx.intern_place_elems(&new_projection);
+    place.projection = tcx.mk_place_elems(&new_projection);
 }
 
 const SELF_ARG: Local = Local::from_u32(1);
@@ -300,7 +299,7 @@ impl<'tcx> TransformVisitor<'tcx> {
         let mut projection = base.projection.to_vec();
         projection.push(ProjectionElem::Field(Field::new(idx), ty));
 
-        Place { local: base.local, projection: self.tcx.intern_place_elems(&projection) }
+        Place { local: base.local, projection: self.tcx.mk_place_elems(&projection) }
     }
 
     // Create a statement which changes the discriminant
@@ -427,7 +426,7 @@ fn make_generator_state_argument_pinned<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body
 
     let pin_did = tcx.require_lang_item(LangItem::Pin, Some(body.span));
     let pin_adt_ref = tcx.adt_def(pin_did);
-    let substs = tcx.intern_substs(&[ref_gen_ty.into()]);
+    let substs = tcx.mk_substs(&[ref_gen_ty.into()]);
     let pin_ref_gen_ty = tcx.mk_adt(pin_adt_ref, substs);
 
     // Replace the by ref generator argument
@@ -1450,13 +1449,13 @@ impl<'tcx> MirPass<'tcx> for StateTransform {
             // Compute Poll<return_ty>
             let poll_did = tcx.require_lang_item(LangItem::Poll, None);
             let poll_adt_ref = tcx.adt_def(poll_did);
-            let poll_substs = tcx.intern_substs(&[body.return_ty().into()]);
+            let poll_substs = tcx.mk_substs(&[body.return_ty().into()]);
             (poll_adt_ref, poll_substs)
         } else {
             // Compute GeneratorState<yield_ty, return_ty>
             let state_did = tcx.require_lang_item(LangItem::GeneratorState, None);
             let state_adt_ref = tcx.adt_def(state_did);
-            let state_substs = tcx.intern_substs(&[yield_ty.into(), body.return_ty().into()]);
+            let state_substs = tcx.mk_substs(&[yield_ty.into(), body.return_ty().into()]);
             (state_adt_ref, state_substs)
         };
         let ret_ty = tcx.mk_adt(state_adt_ref, state_substs);

compiler/rustc_mir_transform/src/inline.rs

@@ -888,7 +888,7 @@ impl<'tcx> Visitor<'tcx> for CostChecker<'_, 'tcx> {
         location: Location,
     ) {
         if let ProjectionElem::Field(f, ty) = elem {
-            let parent = Place { local, projection: self.tcx.intern_place_elems(proj_base) };
+            let parent = Place { local, projection: self.tcx.mk_place_elems(proj_base) };
             let parent_ty = parent.ty(&self.callee_body.local_decls, self.tcx);
             let check_equal = |this: &mut Self, f_ty| {
                 if !util::is_equal_up_to_subtyping(this.tcx, this.param_env, ty, f_ty) {

compiler/rustc_mir_transform/src/instcombine.rs

@@ -121,7 +121,7 @@ impl<'tcx> InstCombineContext<'tcx, '_> {
 
                 *rvalue = Rvalue::Use(Operand::Copy(Place {
                     local: base.local,
-                    projection: self.tcx.intern_place_elems(base.projection),
+                    projection: self.tcx.mk_place_elems(base.projection),
                 }));
             }
         }

compiler/rustc_mir_transform/src/large_enums.rs

@@ -114,7 +114,7 @@ impl EnumSizeOpt {
             tcx.data_layout.ptr_sized_integer().align(&tcx.data_layout).abi,
             Mutability::Not,
         );
-        let alloc = tcx.create_memory_alloc(tcx.intern_const_alloc(alloc));
+        let alloc = tcx.create_memory_alloc(tcx.mk_const_alloc(alloc));
         Some((*adt_def, num_discrs, *alloc_cache.entry(ty).or_insert(alloc)))
     }
     fn optim<'tcx>(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
@@ -197,9 +197,8 @@ impl EnumSizeOpt {
                             size_place,
                             Rvalue::Use(Operand::Copy(Place {
                                 local: size_array_local,
-                                projection: tcx.intern_place_elems(&[PlaceElem::Index(
+                                projection: tcx
-                                    discr_cast_place.local,
+                                    .mk_place_elems(&[PlaceElem::Index(discr_cast_place.local)]),
-                                )]),
                             })),
                         )),
                     };

compiler/rustc_mir_transform/src/lib.rs

@@ -192,7 +192,7 @@ fn remap_mir_for_const_eval_select<'tcx>(
                 let arguments = (0..num_args).map(|x| {
                     let mut place_elems = place_elems.to_vec();
                     place_elems.push(ProjectionElem::Field(x.into(), fields[x]));
-                    let projection = tcx.intern_place_elems(&place_elems);
+                    let projection = tcx.mk_place_elems(&place_elems);
                     let place = Place {
                         local: place.local,
                         projection,

compiler/rustc_mir_transform/src/shim.rs

@@ -147,7 +147,7 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>)
     assert!(!matches!(ty, Some(ty) if ty.is_generator()));
 
     let substs = if let Some(ty) = ty {
-        tcx.intern_substs(&[ty.into()])
+        tcx.mk_substs(&[ty.into()])
     } else {
         InternalSubsts::identity_for_item(tcx, def_id)
     };
@@ -597,7 +597,7 @@ fn build_call_shim<'tcx>(
         let untuple_args = sig.inputs();
 
         // Create substitutions for the `Self` and `Args` generic parameters of the shim body.
-        let arg_tup = tcx.intern_tup(untuple_args);
+        let arg_tup = tcx.mk_tup(untuple_args);
 
         (Some([ty.into(), arg_tup.into()]), Some(untuple_args))
     } else {
@@ -632,7 +632,7 @@ fn build_call_shim<'tcx>(
             Adjustment::Deref => tcx.mk_imm_ptr(fnty),
             Adjustment::RefMut => tcx.mk_mut_ptr(fnty),
         };
-        sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
+        sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
     }
 
     // FIXME(eddyb) avoid having this snippet both here and in
@@ -643,7 +643,7 @@ fn build_call_shim<'tcx>(
         let self_arg = &mut inputs_and_output[0];
         debug_assert!(tcx.generics_of(def_id).has_self && *self_arg == tcx.types.self_param);
         *self_arg = tcx.mk_mut_ptr(*self_arg);
-        sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
+        sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
     }
 
     let span = tcx.def_span(def_id);

compiler/rustc_mir_transform/src/sroa.rs

@@ -122,7 +122,7 @@ impl<'tcx> ReplacementMap<'tcx> {
         let &[PlaceElem::Field(f, _), ref rest @ ..] = place.projection else { return None; };
         let fields = self.fragments[place.local].as_ref()?;
         let (_, new_local) = fields[f]?;
-        Some(Place { local: new_local, projection: tcx.intern_place_elems(&rest) })
+        Some(Place { local: new_local, projection: tcx.mk_place_elems(&rest) })
     }
 
     fn place_fragments(

compiler/rustc_monomorphize/src/collector.rs

@@ -1298,7 +1298,7 @@ impl<'v> RootCollector<'_, 'v> {
             self.tcx,
             ty::ParamEnv::reveal_all(),
             start_def_id,
-            self.tcx.intern_substs(&[main_ret_ty.into()]),
+            self.tcx.mk_substs(&[main_ret_ty.into()]),
         )
         .unwrap()
         .unwrap();

compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs

@@ -675,7 +675,7 @@ fn transform_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, options: TransformTyOptio
         _ if ty.is_unit() => {}
 
         ty::Tuple(tys) => {
-            ty = tcx.mk_tup(tys.iter().map(|ty| transform_ty(tcx, ty, options)));
+            ty = tcx.mk_tup_from_iter(tys.iter().map(|ty| transform_ty(tcx, ty, options)));
         }
 
         ty::Array(ty0, len) => {
@@ -825,7 +825,7 @@ fn transform_substs<'tcx>(
             subst
         }
     });
-    tcx.mk_substs(substs)
+    tcx.mk_substs_from_iter(substs)
 }
 
 /// Returns a type metadata identifier for the specified FnAbi using the Itanium C++ ABI with vendor

compiler/rustc_trait_selection/src/solve/mod.rs

@@ -567,7 +567,7 @@ fn compute_external_query_constraints<'tcx>(
 ) -> Result<ExternalConstraints<'tcx>, NoSolution> {
     let region_obligations = infcx.take_registered_region_obligations();
     let opaque_types = infcx.take_opaque_types_for_query_response();
-    Ok(infcx.tcx.intern_external_constraints(ExternalConstraintsData {
+    Ok(infcx.tcx.mk_external_constraints(ExternalConstraintsData {
         // FIXME: Now that's definitely wrong :)
         //
         // Should also do the leak check here I think
@@ -616,8 +616,7 @@ pub(super) fn response_no_constraints<'tcx>(
             var_values: CanonicalVarValues::make_identity(tcx, goal.variables),
             // FIXME: maybe we should store the "no response" version in tcx, like
             // we do for tcx.types and stuff.
-            external_constraints: tcx
+            external_constraints: tcx.mk_external_constraints(ExternalConstraintsData::default()),
-                .intern_external_constraints(ExternalConstraintsData::default()),
             certainty,
         },
     })

compiler/rustc_trait_selection/src/solve/trait_goals.rs

@@ -343,9 +343,10 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
                     // Substitute just the unsizing params from B into A. The type after
                     // this substitution must be equal to B. This is so we don't unsize
                     // unrelated type parameters.
-                    let new_a_substs = tcx.mk_substs(a_substs.iter().enumerate().map(|(i, a)| {
+                    let new_a_substs =
-                        if unsizing_params.contains(i as u32) { b_substs[i] } else { a }
+                        tcx.mk_substs_from_iter(a_substs.iter().enumerate().map(|(i, a)| {
-                    }));
+                            if unsizing_params.contains(i as u32) { b_substs[i] } else { a }
+                        }));
                     let unsized_a_ty = tcx.mk_adt(a_def, new_a_substs);
 
                     // Finally, we require that `TailA: Unsize<TailB>` for the tail field
@@ -368,7 +369,8 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
                     let b_last_ty = b_tys.last().unwrap();
 
                     // Substitute just the tail field of B., and require that they're equal.
-                    let unsized_a_ty = tcx.mk_tup(a_rest_tys.iter().chain([b_last_ty]).copied());
+                    let unsized_a_ty =
+                        tcx.mk_tup_from_iter(a_rest_tys.iter().chain([b_last_ty]).copied());
                     let mut nested_goals = ecx.eq(goal.param_env, unsized_a_ty, b_ty)?;
 
                     // Similar to ADTs, require that the rest of the fields are equal.
@@ -425,7 +427,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
                             .map(ty::ExistentialPredicate::AutoTrait)
                             .map(ty::Binder::dummy),
                     );
-                let new_a_data = tcx.mk_poly_existential_predicates(new_a_data);
+                let new_a_data = tcx.mk_poly_existential_predicates_from_iter(new_a_data);
                 let new_a_ty = tcx.mk_dynamic(new_a_data, b_region, ty::Dyn);
 
                 // We also require that A's lifetime outlives B's lifetime.

compiler/rustc_trait_selection/src/solve/trait_goals/structural_traits.rs

@@ -189,11 +189,9 @@ pub(crate) fn extract_tupled_inputs_and_output_from_callable<'tcx>(
         ty::FnDef(def_id, substs) => Ok(Some(
             tcx.fn_sig(def_id)
                 .subst(tcx, substs)
-                .map_bound(|sig| (tcx.intern_tup(sig.inputs()), sig.output())),
+                .map_bound(|sig| (tcx.mk_tup(sig.inputs()), sig.output())),
         )),
-        ty::FnPtr(sig) => {
+        ty::FnPtr(sig) => Ok(Some(sig.map_bound(|sig| (tcx.mk_tup(sig.inputs()), sig.output())))),
-            Ok(Some(sig.map_bound(|sig| (tcx.intern_tup(sig.inputs()), sig.output()))))
-        }
         ty::Closure(_, substs) => {
             let closure_substs = substs.as_closure();
             match closure_substs.kind_ty().to_opt_closure_kind() {

compiler/rustc_trait_selection/src/traits/auto_trait.rs

@@ -350,14 +350,14 @@ impl<'tcx> AutoTraitFinder<'tcx> {
             )
             .map(|o| o.predicate);
             new_env = ty::ParamEnv::new(
-                tcx.mk_predicates(normalized_preds),
+                tcx.mk_predicates_from_iter(normalized_preds),
                 param_env.reveal(),
                 param_env.constness(),
             );
         }
 
         let final_user_env = ty::ParamEnv::new(
-            tcx.mk_predicates(user_computed_preds.into_iter()),
+            tcx.mk_predicates_from_iter(user_computed_preds.into_iter()),
             user_env.reveal(),
             user_env.constness(),
         );

compiler/rustc_trait_selection/src/traits/mod.rs

@@ -281,7 +281,7 @@ pub fn normalize_param_env_or_error<'tcx>(
     debug!("normalize_param_env_or_error: elaborated-predicates={:?}", predicates);
 
     let elaborated_env = ty::ParamEnv::new(
-        tcx.intern_predicates(&predicates),
+        tcx.mk_predicates(&predicates),
         unnormalized_env.reveal(),
         unnormalized_env.constness(),
     );
@@ -333,10 +333,9 @@ pub fn normalize_param_env_or_error<'tcx>(
     // Not sure whether it is better to include the unnormalized TypeOutlives predicates
     // here. I believe they should not matter, because we are ignoring TypeOutlives param-env
     // predicates here anyway. Keeping them here anyway because it seems safer.
-    let outlives_env: Vec<_> =
+    let outlives_env = non_outlives_predicates.iter().chain(&outlives_predicates).cloned();
-        non_outlives_predicates.iter().chain(&outlives_predicates).cloned().collect();
     let outlives_env = ty::ParamEnv::new(
-        tcx.intern_predicates(&outlives_env),
+        tcx.mk_predicates_from_iter(outlives_env),
         unnormalized_env.reveal(),
         unnormalized_env.constness(),
     );
@@ -356,7 +355,7 @@ pub fn normalize_param_env_or_error<'tcx>(
     predicates.extend(outlives_predicates);
     debug!("normalize_param_env_or_error: final predicates={:?}", predicates);
     ty::ParamEnv::new(
-        tcx.intern_predicates(&predicates),
+        tcx.mk_predicates(&predicates),
         unnormalized_env.reveal(),
         unnormalized_env.constness(),
     )

compiler/rustc_trait_selection/src/traits/object_safety.rs

@@ -18,10 +18,10 @@ use rustc_errors::{DelayDm, FatalError, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::subst::{GenericArg, InternalSubsts};
+use rustc_middle::ty::ToPredicate;
 use rustc_middle::ty::{
     self, EarlyBinder, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor,
 };
-use rustc_middle::ty::{Predicate, ToPredicate};
 use rustc_session::lint::builtin::WHERE_CLAUSES_OBJECT_SAFETY;
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
@@ -666,8 +666,9 @@ fn object_ty_for_trait<'tcx>(
     elaborated_predicates.sort_by(|a, b| a.skip_binder().stable_cmp(tcx, &b.skip_binder()));
     elaborated_predicates.dedup();
 
-    let existential_predicates = tcx
+    let existential_predicates = tcx.mk_poly_existential_predicates_from_iter(
-        .mk_poly_existential_predicates(iter::once(trait_predicate).chain(elaborated_predicates));
+        iter::once(trait_predicate).chain(elaborated_predicates),
+    );
     debug!(?existential_predicates);
 
     tcx.mk_dynamic(existential_predicates, lifetime, ty::Dyn)
@@ -766,11 +767,11 @@ fn receiver_is_dispatchable<'tcx>(
             ty::Binder::dummy(tcx.mk_trait_ref(trait_def_id, substs)).to_predicate(tcx)
         };
 
-        let caller_bounds: Vec<Predicate<'tcx>> =
+        let caller_bounds =
-            param_env.caller_bounds().iter().chain([unsize_predicate, trait_predicate]).collect();
+            param_env.caller_bounds().iter().chain([unsize_predicate, trait_predicate]);
 
         ty::ParamEnv::new(
-            tcx.intern_predicates(&caller_bounds),
+            tcx.mk_predicates_from_iter(caller_bounds),
             param_env.reveal(),
             param_env.constness(),
         )

compiler/rustc_trait_selection/src/traits/project.rs

@@ -1906,7 +1906,7 @@ fn confirm_builtin_candidate<'cx, 'tcx>(
 ) -> Progress<'tcx> {
     let tcx = selcx.tcx();
     let self_ty = obligation.predicate.self_ty();
-    let substs = tcx.intern_substs(&[self_ty.into()]);
+    let substs = tcx.mk_substs(&[self_ty.into()]);
     let lang_items = tcx.lang_items();
     let item_def_id = obligation.predicate.def_id;
     let trait_def_id = tcx.trait_of_item(item_def_id).unwrap();

compiler/rustc_trait_selection/src/traits/select/confirmation.rs

@@ -564,8 +564,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                                 .into()
                             }
                         });
-                        let bound_vars = tcx.intern_bound_variable_kinds(&bound_vars);
+                        let bound_vars = tcx.mk_bound_variable_kinds(&bound_vars);
-                        let assoc_ty_substs = tcx.intern_substs(&substs);
+                        let assoc_ty_substs = tcx.mk_substs(&substs);
                         let bound =
                             bound.map_bound(|b| b.kind().skip_binder()).subst(tcx, assoc_ty_substs);
                         tcx.mk_predicate(ty::Binder::bind_with_vars(bound, bound_vars))
@@ -880,7 +880,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                             .map(ty::ExistentialPredicate::AutoTrait)
                             .map(ty::Binder::dummy),
                     );
-                let existential_predicates = tcx.mk_poly_existential_predicates(iter);
+                let existential_predicates = tcx.mk_poly_existential_predicates_from_iter(iter);
                 let source_trait = tcx.mk_dynamic(existential_predicates, r_b, repr_a);
 
                 // Require that the traits involved in this upcast are **equal**;
@@ -979,7 +979,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                             .map(ty::ExistentialPredicate::AutoTrait)
                             .map(ty::Binder::dummy),
                     );
-                let existential_predicates = tcx.mk_poly_existential_predicates(iter);
+                let existential_predicates = tcx.mk_poly_existential_predicates_from_iter(iter);
                 let source_trait = tcx.mk_dynamic(existential_predicates, r_b, dyn_a);
 
                 // Require that the traits involved in this upcast are **equal**;
@@ -1099,7 +1099,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
                 // Check that the source struct with the target's
                 // unsizing parameters is equal to the target.
-                let substs = tcx.mk_substs(substs_a.iter().enumerate().map(|(i, k)| {
+                let substs = tcx.mk_substs_from_iter(substs_a.iter().enumerate().map(|(i, k)| {
                     if unsizing_params.contains(i as u32) { substs_b[i] } else { k }
                 }));
                 let new_struct = tcx.mk_adt(def, substs);
@@ -1131,7 +1131,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
                 // Check that the source tuple with the target's
                 // last element is equal to the target.
-                let new_tuple = tcx.mk_tup(a_mid.iter().copied().chain(iter::once(b_last)));
+                let new_tuple =
+                    tcx.mk_tup_from_iter(a_mid.iter().copied().chain(iter::once(b_last)));
                 let InferOk { obligations, .. } = self
                     .infcx
                     .at(&obligation.cause, obligation.param_env)

compiler/rustc_trait_selection/src/traits/select/mod.rs

@@ -2230,7 +2230,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                     }
                 }
                 // (*) binder moved here
-                let all_vars = self.tcx().mk_bound_variable_kinds(
+                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))
@@ -3034,7 +3034,7 @@ fn bind_generator_hidden_types_above<'tcx>(
     if considering_regions {
         debug_assert!(!hidden_types.has_erased_regions());
     }
-    let bound_vars = tcx.mk_bound_variable_kinds(bound_vars.iter().chain(
+    let bound_vars = tcx.mk_bound_variable_kinds_from_iter(bound_vars.iter().chain(
         (num_bound_variables..counter).map(|i| ty::BoundVariableKind::Region(ty::BrAnon(i, None))),
     ));
     ty::Binder::bind_with_vars(hidden_types, bound_vars)

compiler/rustc_trait_selection/src/traits/util.rs

@@ -292,7 +292,7 @@ pub fn closure_trait_ref_and_return_type<'tcx>(
     assert!(!self_ty.has_escaping_bound_vars());
     let arguments_tuple = match tuple_arguments {
         TupleArgumentsFlag::No => sig.skip_binder().inputs()[0],
-        TupleArgumentsFlag::Yes => tcx.intern_tup(sig.skip_binder().inputs()),
+        TupleArgumentsFlag::Yes => tcx.mk_tup(sig.skip_binder().inputs()),
     };
     let trait_ref = tcx.mk_trait_ref(fn_trait_def_id, [self_ty, arguments_tuple]);
     sig.map_bound(|sig| (trait_ref, sig.output()))

compiler/rustc_traits/src/chalk/lowering.rs

@@ -62,7 +62,9 @@ impl<'tcx> LowerInto<'tcx, chalk_ir::Substitution<RustInterner<'tcx>>> for Subst
 
 impl<'tcx> LowerInto<'tcx, SubstsRef<'tcx>> for &chalk_ir::Substitution<RustInterner<'tcx>> {
     fn lower_into(self, interner: RustInterner<'tcx>) -> SubstsRef<'tcx> {
-        interner.tcx.mk_substs(self.iter(interner).map(|subst| subst.lower_into(interner)))
+        interner
+            .tcx
+            .mk_substs_from_iter(self.iter(interner).map(|subst| subst.lower_into(interner)))
     }
 }
 

compiler/rustc_traits/src/chalk/mod.rs

@@ -96,7 +96,7 @@ pub(crate) fn evaluate_goal<'tcx>(
         use rustc_middle::infer::canonical::CanonicalVarInfo;
 
         let mut reverse_param_substitutor = ReverseParamsSubstitutor::new(tcx, params);
-        let var_values = tcx.mk_substs(
+        let var_values = tcx.mk_substs_from_iter(
             subst
                 .as_slice(interner)
                 .iter()
@@ -126,7 +126,7 @@ pub(crate) fn evaluate_goal<'tcx>(
         let max_universe = binders.iter(interner).map(|v| v.skip_kind().counter).max().unwrap_or(0);
         let sol = Canonical {
             max_universe: ty::UniverseIndex::from_usize(max_universe),
-            variables: tcx.intern_canonical_var_infos(&variables),
+            variables: tcx.mk_canonical_var_infos(&variables),
             value: QueryResponse {
                 var_values: CanonicalVarValues { var_values },
                 region_constraints: QueryRegionConstraints::default(),

compiler/rustc_ty_utils/src/abi.rs

@@ -54,7 +54,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 sig = sig.map_bound(|mut sig| {
                     let mut inputs_and_output = sig.inputs_and_output.to_vec();
                     inputs_and_output[0] = tcx.mk_mut_ptr(inputs_and_output[0]);
-                    sig.inputs_and_output = tcx.intern_type_list(&inputs_and_output);
+                    sig.inputs_and_output = tcx.mk_type_list(&inputs_and_output);
                     sig
                 });
             }
@@ -63,7 +63,7 @@ fn fn_sig_for_fn_abi<'tcx>(
         ty::Closure(def_id, substs) => {
             let sig = substs.as_closure().sig();
 
-            let bound_vars = tcx.mk_bound_variable_kinds(
+            let bound_vars = tcx.mk_bound_variable_kinds_from_iter(
                 sig.bound_vars().iter().chain(iter::once(ty::BoundVariableKind::Region(ty::BrEnv))),
             );
             let br = ty::BoundRegion {
@@ -88,7 +88,7 @@ fn fn_sig_for_fn_abi<'tcx>(
         ty::Generator(did, substs, _) => {
             let sig = substs.as_generator().poly_sig();
 
-            let bound_vars = tcx.mk_bound_variable_kinds(
+            let bound_vars = tcx.mk_bound_variable_kinds_from_iter(
                 sig.bound_vars().iter().chain(iter::once(ty::BoundVariableKind::Region(ty::BrEnv))),
             );
             let br = ty::BoundRegion {
@@ -99,7 +99,7 @@ fn fn_sig_for_fn_abi<'tcx>(
 
             let pin_did = tcx.require_lang_item(LangItem::Pin, None);
             let pin_adt_ref = tcx.adt_def(pin_did);
-            let pin_substs = tcx.intern_substs(&[env_ty.into()]);
+            let pin_substs = tcx.mk_substs(&[env_ty.into()]);
             let env_ty = tcx.mk_adt(pin_adt_ref, pin_substs);
 
             let sig = sig.skip_binder();
@@ -111,7 +111,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 // The signature should be `Future::poll(_, &mut Context<'_>) -> Poll<Output>`
                 let poll_did = tcx.require_lang_item(LangItem::Poll, None);
                 let poll_adt_ref = tcx.adt_def(poll_did);
-                let poll_substs = tcx.intern_substs(&[sig.return_ty.into()]);
+                let poll_substs = tcx.mk_substs(&[sig.return_ty.into()]);
                 let ret_ty = tcx.mk_adt(poll_adt_ref, poll_substs);
 
                 // We have to replace the `ResumeTy` that is used for type and borrow checking
@@ -133,7 +133,7 @@ fn fn_sig_for_fn_abi<'tcx>(
                 // The signature should be `Generator::resume(_, Resume) -> GeneratorState<Yield, Return>`
                 let state_did = tcx.require_lang_item(LangItem::GeneratorState, None);
                 let state_adt_ref = tcx.adt_def(state_did);
-                let state_substs = tcx.intern_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
+                let state_substs = tcx.mk_substs(&[sig.yield_ty.into(), sig.return_ty.into()]);
                 let ret_ty = tcx.mk_adt(state_adt_ref, state_substs);
 
                 (sig.resume_ty, ret_ty)

compiler/rustc_ty_utils/src/consts.rs

@@ -144,7 +144,7 @@ fn recurse_build<'tcx>(
             for &id in args.iter() {
                 new_args.push(recurse_build(tcx, body, id, root_span)?);
             }
-            let new_args = tcx.intern_const_list(&new_args);
+            let new_args = tcx.mk_const_list(&new_args);
             tcx.mk_const(Expr::FunctionCall(fun, new_args), node.ty)
         }
         &ExprKind::Binary { op, lhs, rhs } if check_binop(op) => {

compiler/rustc_ty_utils/src/implied_bounds.rs

@@ -19,16 +19,16 @@ fn assumed_wf_types(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::List<Ty<'_>> {
             let mut assumed_wf_types: Vec<_> =
                 tcx.assumed_wf_types(tcx.parent(def_id)).as_slice().into();
             assumed_wf_types.extend(liberated_sig.inputs_and_output);
-            tcx.intern_type_list(&assumed_wf_types)
+            tcx.mk_type_list(&assumed_wf_types)
         }
         DefKind::Impl { .. } => {
             match tcx.impl_trait_ref(def_id) {
                 Some(trait_ref) => {
                     let types: Vec<_> = trait_ref.skip_binder().substs.types().collect();
-                    tcx.intern_type_list(&types)
+                    tcx.mk_type_list(&types)
                 }
                 // Only the impl self type
-                None => tcx.intern_type_list(&[tcx.type_of(def_id).subst_identity()]),
+                None => tcx.mk_type_list(&[tcx.type_of(def_id).subst_identity()]),
             }
         }
         DefKind::AssocConst | DefKind::AssocTy => tcx.assumed_wf_types(tcx.parent(def_id)),