Cargo.lock

@@ -3958,6 +3958,7 @@ dependencies = [
  "rustc_session",
  "rustc_span",
  "rustc_target",
+ "rustc_type_ir",
  "smallvec",
  "thin-vec",
  "tracing",

compiler/rustc_ast/src/ast.rs

@@ -3075,7 +3075,8 @@ mod size_asserts {
     static_assert_size!(Block, 48);
     static_assert_size!(Expr, 104);
     static_assert_size!(ExprKind, 72);
-    static_assert_size!(Fn, 192);
+    #[cfg(not(bootstrap))]
+    static_assert_size!(Fn, 184);
     static_assert_size!(ForeignItem, 96);
     static_assert_size!(ForeignItemKind, 24);
     static_assert_size!(GenericArg, 24);

compiler/rustc_ast_lowering/src/expr.rs

@@ -849,21 +849,22 @@ impl<'hir> LoweringContext<'_, 'hir> {
             (body_id, generator_option)
         });
 
-        let bound_generic_params = self.lower_lifetime_binder(closure_id, generic_params);
-        // Lower outside new scope to preserve `is_in_loop_condition`.
-        let fn_decl = self.lower_fn_decl(decl, None, FnDeclKind::Closure, None);
-
-        let c = self.arena.alloc(hir::Closure {
-            binder: binder_clause,
-            capture_clause,
-            bound_generic_params,
-            fn_decl,
-            body: body_id,
-            fn_decl_span: self.lower_span(fn_decl_span),
-            movability: generator_option,
-        });
+        self.lower_lifetime_binder(closure_id, generic_params, |lctx, bound_generic_params| {
+            // Lower outside new scope to preserve `is_in_loop_condition`.
+            let fn_decl = lctx.lower_fn_decl(decl, None, FnDeclKind::Closure, None);
+
+            let c = lctx.arena.alloc(hir::Closure {
+                binder: binder_clause,
+                capture_clause,
+                bound_generic_params,
+                fn_decl,
+                body: body_id,
+                fn_decl_span: lctx.lower_span(fn_decl_span),
+                movability: generator_option,
+            });
 
-        hir::ExprKind::Closure(c)
+            hir::ExprKind::Closure(c)
+        })
     }
 
     fn generator_movability_for_fn(
@@ -950,23 +951,23 @@ impl<'hir> LoweringContext<'_, 'hir> {
             body_id
         });
 
-        let bound_generic_params = self.lower_lifetime_binder(closure_id, generic_params);
-
-        // We need to lower the declaration outside the new scope, because we
-        // have to conserve the state of being inside a loop condition for the
-        // closure argument types.
-        let fn_decl = self.lower_fn_decl(&outer_decl, None, FnDeclKind::Closure, None);
-
-        let c = self.arena.alloc(hir::Closure {
-            binder: binder_clause,
-            capture_clause,
-            bound_generic_params,
-            fn_decl,
-            body,
-            fn_decl_span: self.lower_span(fn_decl_span),
-            movability: None,
-        });
-        hir::ExprKind::Closure(c)
+        self.lower_lifetime_binder(closure_id, generic_params, |lctx, bound_generic_params| {
+            // We need to lower the declaration outside the new scope, because we
+            // have to conserve the state of being inside a loop condition for the
+            // closure argument types.
+            let fn_decl = lctx.lower_fn_decl(&outer_decl, None, FnDeclKind::Closure, None);
+
+            let c = lctx.arena.alloc(hir::Closure {
+                binder: binder_clause,
+                capture_clause,
+                bound_generic_params,
+                fn_decl,
+                body,
+                fn_decl_span: lctx.lower_span(fn_decl_span),
+                movability: None,
+            });
+            hir::ExprKind::Closure(c)
+        })
     }
 
     /// Destructure the LHS of complex assignments.
@@ -1128,8 +1129,11 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         &mut ImplTraitContext::Disallowed(ImplTraitPosition::Path),
                     );
                     // Destructure like a tuple struct.
-                    let tuple_struct_pat =
-                        hir::PatKind::TupleStruct(qpath, pats, rest.map(|r| r.0));
+                    let tuple_struct_pat = hir::PatKind::TupleStruct(
+                        qpath,
+                        pats,
+                        hir::DotDotPos::new(rest.map(|r| r.0)),
+                    );
                     return self.pat_without_dbm(lhs.span, tuple_struct_pat);
                 }
             }
@@ -1184,13 +1188,13 @@ impl<'hir> LoweringContext<'_, 'hir> {
             ExprKind::Tup(elements) => {
                 let (pats, rest) =
                     self.destructure_sequence(elements, "tuple", eq_sign_span, assignments);
-                let tuple_pat = hir::PatKind::Tuple(pats, rest.map(|r| r.0));
+                let tuple_pat = hir::PatKind::Tuple(pats, hir::DotDotPos::new(rest.map(|r| r.0)));
                 return self.pat_without_dbm(lhs.span, tuple_pat);
             }
             ExprKind::Paren(e) => {
                 // We special-case `(..)` for consistency with patterns.
                 if let ExprKind::Range(None, None, RangeLimits::HalfOpen) = e.kind {
-                    let tuple_pat = hir::PatKind::Tuple(&[], Some(0));
+                    let tuple_pat = hir::PatKind::Tuple(&[], hir::DotDotPos::new(Some(0)));
                     return self.pat_without_dbm(lhs.span, tuple_pat);
                 } else {
                     return self.destructure_assign_mut(e, eq_sign_span, assignments);

compiler/rustc_ast_lowering/src/lib.rs

@@ -810,23 +810,31 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     /// name resolver owing to lifetime elision; this also populates the resolver's node-id->def-id
     /// map, so that later calls to `opt_node_id_to_def_id` that refer to these extra lifetime
     /// parameters will be successful.
-    #[instrument(level = "debug", skip(self))]
+    #[instrument(level = "debug", skip(self, in_binder))]
     #[inline]
-    fn lower_lifetime_binder(
+    fn lower_lifetime_binder<R>(
         &mut self,
         binder: NodeId,
         generic_params: &[GenericParam],
-    ) -> &'hir [hir::GenericParam<'hir>] {
-        let mut generic_params: Vec<_> = self.lower_generic_params_mut(generic_params).collect();
+        in_binder: impl FnOnce(&mut Self, &'hir [hir::GenericParam<'hir>]) -> R,
+    ) -> R {
         let extra_lifetimes = self.resolver.take_extra_lifetime_params(binder);
         debug!(?extra_lifetimes);
-        generic_params.extend(extra_lifetimes.into_iter().filter_map(|(ident, node_id, res)| {
-            self.lifetime_res_to_generic_param(ident, node_id, res)
-        }));
+        let extra_lifetimes: Vec<_> = extra_lifetimes
+            .into_iter()
+            .filter_map(|(ident, node_id, res)| {
+                self.lifetime_res_to_generic_param(ident, node_id, res)
+            })
+            .collect();
+
+        let generic_params: Vec<_> = self
+            .lower_generic_params_mut(generic_params)
+            .chain(extra_lifetimes.into_iter())
+            .collect();
         let generic_params = self.arena.alloc_from_iter(generic_params);
         debug!(?generic_params);
 
-        generic_params
+        in_binder(self, generic_params)
     }
 
     fn with_dyn_type_scope<T>(&mut self, in_scope: bool, f: impl FnOnce(&mut Self) -> T) -> T {
@@ -1196,7 +1204,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 let lifetime_bound = this.elided_dyn_bound(t.span);
                 (bounds, lifetime_bound)
             });
-            let kind = hir::TyKind::TraitObject(bounds, lifetime_bound, TraitObjectSyntax::None);
+            let kind = hir::TyKind::TraitObject(bounds, &lifetime_bound, TraitObjectSyntax::None);
             return hir::Ty { kind, span: self.lower_span(t.span), hir_id: self.next_id() };
         }
 
@@ -1236,14 +1244,15 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 hir::TyKind::Rptr(lifetime, self.lower_mt(mt, itctx))
             }
             TyKind::BareFn(ref f) => {
-                let generic_params = self.lower_lifetime_binder(t.id, &f.generic_params);
-                hir::TyKind::BareFn(self.arena.alloc(hir::BareFnTy {
-                    generic_params,
-                    unsafety: self.lower_unsafety(f.unsafety),
-                    abi: self.lower_extern(f.ext),
-                    decl: self.lower_fn_decl(&f.decl, None, FnDeclKind::Pointer, None),
-                    param_names: self.lower_fn_params_to_names(&f.decl),
-                }))
+                self.lower_lifetime_binder(t.id, &f.generic_params, |lctx, generic_params| {
+                    hir::TyKind::BareFn(lctx.arena.alloc(hir::BareFnTy {
+                        generic_params,
+                        unsafety: lctx.lower_unsafety(f.unsafety),
+                        abi: lctx.lower_extern(f.ext),
+                        decl: lctx.lower_fn_decl(&f.decl, None, FnDeclKind::Pointer, None),
+                        param_names: lctx.lower_fn_params_to_names(&f.decl),
+                    }))
+                })
             }
             TyKind::Never => hir::TyKind::Never,
             TyKind::Tup(ref tys) => hir::TyKind::Tup(
@@ -1934,8 +1943,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 let res = res.unwrap_or(
                     self.resolver.get_lifetime_res(lifetime.id).unwrap_or(LifetimeRes::Error),
                 );
-                let l = self.new_named_lifetime_with_res(id, span, ident, res);
-                hir::GenericArg::Lifetime(l)
+                hir::GenericArg::Lifetime(self.new_named_lifetime_with_res(id, span, ident, res))
             },
         ));
 
@@ -2004,7 +2012,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         }
     }
 
-    fn lower_lifetime(&mut self, l: &Lifetime) -> hir::Lifetime {
+    fn lower_lifetime(&mut self, l: &Lifetime) -> &'hir hir::Lifetime {
         let span = self.lower_span(l.ident.span);
         let ident = self.lower_ident(l.ident);
         self.new_named_lifetime(l.id, l.id, span, ident)
@@ -2017,7 +2025,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         span: Span,
         ident: Ident,
         res: LifetimeRes,
-    ) -> hir::Lifetime {
+    ) -> &'hir hir::Lifetime {
         let name = match res {
             LifetimeRes::Param { param, .. } => {
                 let p_name = ParamName::Plain(ident);
@@ -2038,7 +2046,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         };
 
         debug!(?name);
-        hir::Lifetime { hir_id: self.lower_node_id(id), span: self.lower_span(span), name }
+        self.arena.alloc(hir::Lifetime {
+            hir_id: self.lower_node_id(id),
+            span: self.lower_span(span),
+            name,
+        })
     }
 
     #[instrument(level = "debug", skip(self))]
@@ -2048,7 +2060,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         new_id: NodeId,
         span: Span,
         ident: Ident,
-    ) -> hir::Lifetime {
+    ) -> &'hir hir::Lifetime {
         let res = self.resolver.get_lifetime_res(id).unwrap_or(LifetimeRes::Error);
         self.new_named_lifetime_with_res(new_id, span, ident, res)
     }
@@ -2140,10 +2152,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         p: &PolyTraitRef,
         itctx: &mut ImplTraitContext,
     ) -> hir::PolyTraitRef<'hir> {
-        let bound_generic_params =
-            self.lower_lifetime_binder(p.trait_ref.ref_id, &p.bound_generic_params);
-        let trait_ref = self.lower_trait_ref(&p.trait_ref, itctx);
-        hir::PolyTraitRef { bound_generic_params, trait_ref, span: self.lower_span(p.span) }
+        self.lower_lifetime_binder(
+            p.trait_ref.ref_id,
+            &p.bound_generic_params,
+            |lctx, bound_generic_params| {
+                let trait_ref = lctx.lower_trait_ref(&p.trait_ref, itctx);
+                hir::PolyTraitRef { bound_generic_params, trait_ref, span: lctx.lower_span(p.span) }
+            },
+        )
     }
 
     fn lower_mt(&mut self, mt: &MutTy, itctx: &mut ImplTraitContext) -> hir::MutTy<'hir> {
@@ -2462,14 +2478,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
     /// bound, like the bound in `Box<dyn Debug>`. This method is not invoked
     /// when the bound is written, even if it is written with `'_` like in
     /// `Box<dyn Debug + '_>`. In those cases, `lower_lifetime` is invoked.
-    fn elided_dyn_bound(&mut self, span: Span) -> hir::Lifetime {
+    fn elided_dyn_bound(&mut self, span: Span) -> &'hir hir::Lifetime {
         let r = hir::Lifetime {
             hir_id: self.next_id(),
             span: self.lower_span(span),
             name: hir::LifetimeName::ImplicitObjectLifetimeDefault,
         };
         debug!("elided_dyn_bound: r={:?}", r);
-        r
+        self.arena.alloc(r)
     }
 }
 

compiler/rustc_ast_lowering/src/pat.rs

@@ -116,7 +116,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         &mut self,
         pats: &[P<Pat>],
         ctx: &str,
-    ) -> (&'hir [hir::Pat<'hir>], Option<usize>) {
+    ) -> (&'hir [hir::Pat<'hir>], hir::DotDotPos) {
         let mut elems = Vec::with_capacity(pats.len());
         let mut rest = None;
 
@@ -160,7 +160,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             }
         }
 
-        (self.arena.alloc_from_iter(elems), rest.map(|(ddpos, _)| ddpos))
+        (self.arena.alloc_from_iter(elems), hir::DotDotPos::new(rest.map(|(ddpos, _)| ddpos)))
     }
 
     /// Lower a slice pattern of form `[pat_0, ..., pat_n]` into

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -135,7 +135,6 @@ pub struct RegionInferenceContext<'tcx> {
 /// adds a new lower bound to the SCC it is analyzing: so you wind up
 /// with `'R: 'O` where `'R` is the pick-region and `'O` is the
 /// minimal viable option.
-#[derive(Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
 pub(crate) struct AppliedMemberConstraint {
     /// The SCC that was affected. (The "member region".)
     ///

compiler/rustc_codegen_cranelift/src/discriminant.rs

@@ -42,10 +42,10 @@ pub(crate) fn codegen_set_discriminant<'tcx>(
         Variants::Multiple {
             tag: _,
             tag_field,
-            tag_encoding: TagEncoding::Niche { dataful_variant, ref niche_variants, niche_start },
+            tag_encoding: TagEncoding::Niche { untagged_variant, ref niche_variants, niche_start },
             variants: _,
         } => {
-            if variant_index != dataful_variant {
+            if variant_index != untagged_variant {
                 let niche = place.place_field(fx, mir::Field::new(tag_field));
                 let niche_value = variant_index.as_u32() - niche_variants.start().as_u32();
                 let niche_value = ty::ScalarInt::try_from_uint(
@@ -113,7 +113,7 @@ pub(crate) fn codegen_get_discriminant<'tcx>(
             let res = CValue::by_val(val, dest_layout);
             dest.write_cvalue(fx, res);
         }
-        TagEncoding::Niche { dataful_variant, ref niche_variants, niche_start } => {
+        TagEncoding::Niche { untagged_variant, ref niche_variants, niche_start } => {
             // Rebase from niche values to discriminants, and check
             // whether the result is in range for the niche variants.
 
@@ -169,8 +169,9 @@ pub(crate) fn codegen_get_discriminant<'tcx>(
                 fx.bcx.ins().iadd_imm(relative_discr, i64::from(niche_variants.start().as_u32()))
             };
 
-            let dataful_variant = fx.bcx.ins().iconst(cast_to, i64::from(dataful_variant.as_u32()));
-            let discr = fx.bcx.ins().select(is_niche, niche_discr, dataful_variant);
+            let untagged_variant =
+                fx.bcx.ins().iconst(cast_to, i64::from(untagged_variant.as_u32()));
+            let discr = fx.bcx.ins().select(is_niche, niche_discr, untagged_variant);
             let res = CValue::by_val(discr, dest_layout);
             dest.write_cvalue(fx, res);
         }