Auto merge of #115831 - nnethercote:remove-unused-Lift-impls, r=bjorn3

Remove unused `Lift` impls

r? `@bjorn3`

compiler/rustc_borrowck/src/diagnostics/region_name.rs

@@ -442,8 +442,8 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
         span: Span,
         counter: usize,
     ) -> RegionNameHighlight {
-        let mut highlight = RegionHighlightMode::new(self.infcx.tcx);
-        highlight.highlighting_region_vid(needle_fr, counter);
+        let mut highlight = RegionHighlightMode::default();
+        highlight.highlighting_region_vid(self.infcx.tcx, needle_fr, counter);
         let type_name =
             self.infcx.extract_inference_diagnostics_data(ty.into(), Some(highlight)).name;
 
@@ -804,8 +804,8 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             return None;
         }
 
-        let mut highlight = RegionHighlightMode::new(tcx);
-        highlight.highlighting_region_vid(fr, *self.next_region_name.try_borrow().unwrap());
+        let mut highlight = RegionHighlightMode::default();
+        highlight.highlighting_region_vid(tcx, fr, *self.next_region_name.try_borrow().unwrap());
         let type_name =
             self.infcx.extract_inference_diagnostics_data(yield_ty.into(), Some(highlight)).name;
 

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/placeholder_error.rs

@@ -385,7 +385,7 @@ impl<'tcx> NiceRegionError<'_, 'tcx> {
 
         let highlight_trait_ref = |trait_ref| Highlighted {
             tcx: self.tcx(),
-            highlight: RegionHighlightMode::new(self.tcx()),
+            highlight: RegionHighlightMode::default(),
             value: trait_ref,
         };
 

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs

@@ -67,9 +67,9 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         }
 
         impl<'tcx> HighlightBuilder<'tcx> {
-            fn build(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> RegionHighlightMode<'tcx> {
+            fn build(ty: Ty<'tcx>) -> RegionHighlightMode<'tcx> {
                 let mut builder =
-                    HighlightBuilder { highlight: RegionHighlightMode::new(tcx), counter: 1 };
+                    HighlightBuilder { highlight: RegionHighlightMode::default(), counter: 1 };
                 builder.visit_ty(ty);
                 builder.highlight
             }
@@ -85,12 +85,12 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             }
         }
 
-        let expected_highlight = HighlightBuilder::build(self.tcx(), expected);
+        let expected_highlight = HighlightBuilder::build(expected);
         let expected = self
             .cx
             .extract_inference_diagnostics_data(expected.into(), Some(expected_highlight))
             .name;
-        let found_highlight = HighlightBuilder::build(self.tcx(), found);
+        let found_highlight = HighlightBuilder::build(found);
         let found =
             self.cx.extract_inference_diagnostics_data(found.into(), Some(found_highlight)).name;
 

compiler/rustc_infer/src/infer/free_regions.rs

@@ -4,7 +4,7 @@
 //! and use that to decide when one free region outlives another, and so forth.
 
 use rustc_data_structures::transitive_relation::TransitiveRelation;
-use rustc_middle::ty::{Lift, Region, TyCtxt};
+use rustc_middle::ty::{Region, TyCtxt};
 
 /// Combines a `FreeRegionMap` and a `TyCtxt`.
 ///
@@ -101,10 +101,3 @@ impl<'tcx> FreeRegionMap<'tcx> {
         result
     }
 }
-
-impl<'a, 'tcx> Lift<'tcx> for FreeRegionMap<'a> {
-    type Lifted = FreeRegionMap<'tcx>;
-    fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<FreeRegionMap<'tcx>> {
-        self.relation.maybe_map(|fr| tcx.lift(fr)).map(|relation| FreeRegionMap { relation })
-    }
-}

compiler/rustc_middle/src/infer/canonical.rs

@@ -34,7 +34,7 @@ use std::ops::Index;
 /// variables have been rewritten to "canonical vars". These are
 /// numbered starting from 0 in order of first appearance.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TyDecodable, TyEncodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
+#[derive(HashStable, TypeFoldable, TypeVisitable)]
 pub struct Canonical<'tcx, V> {
     pub value: V,
     pub max_universe: ty::UniverseIndex,
@@ -72,7 +72,7 @@ impl<'tcx> ty::TypeFoldable<TyCtxt<'tcx>> for CanonicalVarInfos<'tcx> {
 /// variables. You will need to supply it later to instantiate the
 /// canonicalized query response.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TyDecodable, TyEncodable)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
+#[derive(HashStable, TypeFoldable, TypeVisitable)]
 pub struct CanonicalVarValues<'tcx> {
     pub var_values: ty::GenericArgsRef<'tcx>,
 }
@@ -311,7 +311,7 @@ pub enum CanonicalTyVarKind {
 /// After we execute a query with a canonicalized key, we get back a
 /// `Canonical<QueryResponse<..>>`. You can use
 /// `instantiate_query_result` to access the data in this result.
-#[derive(Clone, Debug, HashStable, TypeFoldable, TypeVisitable, Lift)]
+#[derive(Clone, Debug, HashStable, TypeFoldable, TypeVisitable)]
 pub struct QueryResponse<'tcx, R> {
     pub var_values: CanonicalVarValues<'tcx>,
     pub region_constraints: QueryRegionConstraints<'tcx>,
@@ -326,7 +326,7 @@ pub struct QueryResponse<'tcx, R> {
 }
 
 #[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
+#[derive(HashStable, TypeFoldable, TypeVisitable)]
 pub struct QueryRegionConstraints<'tcx> {
     pub outlives: Vec<QueryOutlivesConstraint<'tcx>>,
     pub member_constraints: Vec<MemberConstraint<'tcx>>,
@@ -432,7 +432,7 @@ impl<'tcx, V> Canonical<'tcx, V> {
 pub type QueryOutlivesConstraint<'tcx> =
     (ty::OutlivesPredicate<GenericArg<'tcx>, Region<'tcx>>, ConstraintCategory<'tcx>);
 
-TrivialTypeTraversalAndLiftImpls! {
+TrivialTypeTraversalImpls! {
     crate::infer::canonical::Certainty,
     crate::infer::canonical::CanonicalTyVarKind,
 }

compiler/rustc_middle/src/infer/mod.rs

@@ -13,7 +13,7 @@ use rustc_span::Span;
 /// R0 member of [O1..On]
 /// ```
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-#[derive(HashStable, TypeFoldable, TypeVisitable, Lift)]
+#[derive(HashStable, TypeFoldable, TypeVisitable)]
 pub struct MemberConstraint<'tcx> {
     /// The `DefId` and args of the opaque type causing this constraint.
     /// Used for error reporting.

compiler/rustc_middle/src/macros.rs

@@ -42,7 +42,7 @@ macro_rules! span_bug {
 // the impls for you.
 
 #[macro_export]
-macro_rules! CloneLiftImpls {
+macro_rules! TrivialLiftImpls {
     ($($ty:ty),+ $(,)?) => {
         $(
             impl<'tcx> $crate::ty::Lift<'tcx> for $ty {
@@ -96,6 +96,6 @@ macro_rules! TrivialTypeTraversalImpls {
 macro_rules! TrivialTypeTraversalAndLiftImpls {
     ($($t:tt)*) => {
         TrivialTypeTraversalImpls! { $($t)* }
-        CloneLiftImpls! { $($t)* }
+        TrivialLiftImpls! { $($t)* }
     }
 }

compiler/rustc_middle/src/mir/basic_blocks.rs

@@ -178,7 +178,7 @@ impl<'tcx> graph::WithPredecessors for BasicBlocks<'tcx> {
     }
 }
 
-TrivialTypeTraversalAndLiftImpls! { Cache }
+TrivialTypeTraversalImpls! { Cache }
 
 impl<S: Encoder> Encodable<S> for Cache {
     #[inline]

compiler/rustc_middle/src/mir/interpret/error.rs

@@ -67,7 +67,7 @@ impl Into<ErrorGuaranteed> for ReportedErrorInfo {
     }
 }
 
-TrivialTypeTraversalAndLiftImpls! { ErrorHandled }
+TrivialTypeTraversalImpls! { ErrorHandled }
 
 pub type EvalToAllocationRawResult<'tcx> = Result<ConstAlloc<'tcx>, ErrorHandled>;
 pub type EvalToConstValueResult<'tcx> = Result<ConstValue<'tcx>, ErrorHandled>;

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -162,7 +162,7 @@ pub use self::pointer::{Pointer, PointerArithmetic, Provenance};
 /// - A constant
 /// - A static
 #[derive(Copy, Clone, Debug, Eq, PartialEq, Hash, TyEncodable, TyDecodable)]
-#[derive(HashStable, Lift, TypeFoldable, TypeVisitable)]
+#[derive(HashStable, TypeFoldable, TypeVisitable)]
 pub struct GlobalId<'tcx> {
     /// For a constant or static, the `Instance` of the item itself.
     /// For a promoted global, the `Instance` of the function they belong to.

compiler/rustc_middle/src/mir/mod.rs

@@ -744,7 +744,7 @@ pub enum BindingForm<'tcx> {
     RefForGuard,
 }
 
-TrivialTypeTraversalAndLiftImpls! { BindingForm<'tcx> }
+TrivialTypeTraversalImpls! { BindingForm<'tcx> }
 
 mod binding_form_impl {
     use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
@@ -2295,7 +2295,7 @@ pub struct Constant<'tcx> {
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, TyEncodable, TyDecodable, Hash, HashStable, Debug)]
-#[derive(Lift, TypeFoldable, TypeVisitable)]
+#[derive(TypeFoldable, TypeVisitable)]
 pub enum ConstantKind<'tcx> {
     /// This constant came from the type system.
     ///
@@ -2615,7 +2615,7 @@ impl<'tcx> ConstantKind<'tcx> {
 }
 
 /// An unevaluated (potentially generic) constant used in MIR.
-#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, TyEncodable, TyDecodable, Lift)]
+#[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, TyEncodable, TyDecodable)]
 #[derive(Hash, HashStable, TypeFoldable, TypeVisitable)]
 pub struct UnevaluatedConst<'tcx> {
     pub def: DefId,

compiler/rustc_middle/src/mir/query.rs

@@ -334,7 +334,7 @@ rustc_data_structures::static_assert_size!(ConstraintCategory<'_>, 16);
 ///
 /// See also `rustc_const_eval::borrow_check::constraints`.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
-#[derive(TyEncodable, TyDecodable, HashStable, Lift, TypeVisitable, TypeFoldable)]
+#[derive(TyEncodable, TyDecodable, HashStable, TypeVisitable, TypeFoldable)]
 pub enum ConstraintCategory<'tcx> {
     Return(ReturnConstraint),
     Yield,

compiler/rustc_middle/src/mir/type_foldable.rs

@@ -5,7 +5,7 @@ use rustc_ast::InlineAsmTemplatePiece;
 use super::*;
 use crate::ty;
 
-TrivialTypeTraversalAndLiftImpls! {
+TrivialTypeTraversalImpls! {
     BlockTailInfo,
     MirPhase,
     SourceInfo,

compiler/rustc_middle/src/traits/mod.rs

@@ -13,7 +13,7 @@ use crate::infer::canonical::Canonical;
 use crate::mir::ConstraintCategory;
 use crate::ty::abstract_const::NotConstEvaluatable;
 use crate::ty::GenericArgsRef;
-use crate::ty::{self, AdtKind, Ty, TyCtxt};
+use crate::ty::{self, AdtKind, Ty};
 
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, Diagnostic};
@@ -86,7 +86,7 @@ pub enum Reveal {
 ///
 /// We do not want to intern this as there are a lot of obligation causes which
 /// only live for a short period of time.
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub struct ObligationCause<'tcx> {
     pub span: Span,
@@ -194,15 +194,15 @@ impl<'tcx> ObligationCause<'tcx> {
     }
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub struct UnifyReceiverContext<'tcx> {
     pub assoc_item: ty::AssocItem,
     pub param_env: ty::ParamEnv<'tcx>,
     pub args: GenericArgsRef<'tcx>,
 }
 
-#[derive(Clone, PartialEq, Eq, Lift, Default, HashStable)]
+#[derive(Clone, PartialEq, Eq, Default, HashStable)]
 #[derive(TypeVisitable, TypeFoldable, TyEncodable, TyDecodable)]
 pub struct InternedObligationCauseCode<'tcx> {
     /// `None` for `ObligationCauseCode::MiscObligation` (a common case, occurs ~60% of
@@ -238,7 +238,7 @@ impl<'tcx> std::ops::Deref for InternedObligationCauseCode<'tcx> {
     }
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub enum ObligationCauseCode<'tcx> {
     /// Not well classified or should be obvious from the span.
@@ -470,7 +470,7 @@ pub enum WellFormedLoc {
     },
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub struct ImplDerivedObligationCause<'tcx> {
     pub derived: DerivedObligationCause<'tcx>,
@@ -524,14 +524,7 @@ pub enum StatementAsExpression {
     NeedsBoxing,
 }
 
-impl<'tcx> ty::Lift<'tcx> for StatementAsExpression {
-    type Lifted = StatementAsExpression;
-    fn lift_to_tcx(self, _tcx: TyCtxt<'tcx>) -> Option<StatementAsExpression> {
-        Some(self)
-    }
-}
-
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub struct MatchExpressionArmCause<'tcx> {
     pub arm_block_id: Option<hir::HirId>,
@@ -547,7 +540,7 @@ pub struct MatchExpressionArmCause<'tcx> {
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[derive(Lift, TypeFoldable, TypeVisitable, HashStable, TyEncodable, TyDecodable)]
+#[derive(TypeFoldable, TypeVisitable, HashStable, TyEncodable, TyDecodable)]
 pub struct IfExpressionCause<'tcx> {
     pub then_id: hir::HirId,
     pub else_id: hir::HirId,
@@ -557,7 +550,7 @@ pub struct IfExpressionCause<'tcx> {
     pub opt_suggest_box_span: Option<Span>,
 }
 
-#[derive(Clone, Debug, PartialEq, Eq, Lift, HashStable, TyEncodable, TyDecodable)]
+#[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeVisitable, TypeFoldable)]
 pub struct DerivedObligationCause<'tcx> {
     /// The trait predicate of the parent obligation that led to the
@@ -570,7 +563,7 @@ pub struct DerivedObligationCause<'tcx> {
     pub parent_code: InternedObligationCauseCode<'tcx>,
 }
 
-#[derive(Clone, Debug, TypeVisitable, Lift)]
+#[derive(Clone, Debug, TypeVisitable)]
 pub enum SelectionError<'tcx> {
     /// The trait is not implemented.
     Unimplemented,
@@ -593,7 +586,7 @@ pub enum SelectionError<'tcx> {
     OpaqueTypeAutoTraitLeakageUnknown(DefId),
 }
 
-#[derive(Clone, Debug, TypeVisitable, Lift)]
+#[derive(Clone, Debug, TypeVisitable)]
 pub struct SelectionOutputTypeParameterMismatch<'tcx> {
     pub found_trait_ref: ty::PolyTraitRef<'tcx>,
     pub expected_trait_ref: ty::PolyTraitRef<'tcx>,
@@ -638,7 +631,7 @@ pub type SelectionResult<'tcx, T> = Result<Option<T>, SelectionError<'tcx>>;
 /// ### The type parameter `N`
 ///
 /// See explanation on `ImplSourceUserDefinedData`.
-#[derive(Clone, PartialEq, Eq, TyEncodable, TyDecodable, HashStable, Lift)]
+#[derive(Clone, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub enum ImplSource<'tcx, N> {
     /// ImplSource identifying a particular impl.
@@ -704,7 +697,7 @@ impl<'tcx, N> ImplSource<'tcx, N> {
 /// is `Obligation`, as one might expect. During codegen, however, this
 /// is `()`, because codegen only requires a shallow resolution of an
 /// impl, and nested obligations are satisfied later.
-#[derive(Clone, PartialEq, Eq, TyEncodable, TyDecodable, HashStable, Lift)]
+#[derive(Clone, PartialEq, Eq, TyEncodable, TyDecodable, HashStable)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct ImplSourceUserDefinedData<'tcx, N> {
     pub impl_def_id: DefId,
@@ -736,7 +729,7 @@ pub enum BuiltinImplSource {
     TupleUnsizing,
 }
 
-TrivialTypeTraversalAndLiftImpls! { BuiltinImplSource }
+TrivialTypeTraversalImpls! { BuiltinImplSource }
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash, HashStable, PartialOrd, Ord)]
 pub enum ObjectSafetyViolation {