Rollup of 6 pull requests

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -329,41 +329,52 @@ fn bounds_from_generic_predicates<'tcx>(
             _ => {}
         }
     }
-    let generics = if types.is_empty() {
-        "".to_string()
-    } else {
-        format!(
-            "<{}>",
-            types
-                .keys()
-                .filter_map(|t| match t.kind() {
-                    ty::Param(_) => Some(t.to_string()),
-                    // Avoid suggesting the following:
-                    // fn foo<T, <T as Trait>::Bar>(_: T) where T: Trait, <T as Trait>::Bar: Other {}
-                    _ => None,
-                })
-                .collect::<Vec<_>>()
-                .join(", ")
-        )
-    };
+
     let mut where_clauses = vec![];
+    let mut types_str = vec![];
     for (ty, bounds) in types {
-        where_clauses
-            .extend(bounds.into_iter().map(|bound| format!("{}: {}", ty, tcx.def_path_str(bound))));
-    }
-    for projection in &projections {
-        let p = projection.skip_binder();
-        // FIXME: this is not currently supported syntax, we should be looking at the `types` and
-        // insert the associated types where they correspond, but for now let's be "lazy" and
-        // propose this instead of the following valid resugaring:
-        // `T: Trait, Trait::Assoc = K` → `T: Trait<Assoc = K>`
-        where_clauses.push(format!("{} = {}", tcx.def_path_str(p.projection_ty.def_id), p.term));
+        if let ty::Param(_) = ty.kind() {
+            let mut bounds_str = vec![];
+            for bound in bounds {
+                let mut projections_str = vec![];
+                for projection in &projections {
+                    let p = projection.skip_binder();
+                    let alias_ty = p.projection_ty;
+                    if bound == tcx.parent(alias_ty.def_id) && alias_ty.self_ty() == ty {
+                        let name = tcx.item_name(alias_ty.def_id);
+                        projections_str.push(format!("{} = {}", name, p.term));
+                    }
+                }
+                let bound_def_path = tcx.def_path_str(bound);
+                if projections_str.is_empty() {
+                    where_clauses.push(format!("{}: {}", ty, bound_def_path));
+                } else {
+                    bounds_str.push(format!("{}<{}>", bound_def_path, projections_str.join(", ")));
+                }
+            }
+            if bounds_str.is_empty() {
+                types_str.push(ty.to_string());
+            } else {
+                types_str.push(format!("{}: {}", ty, bounds_str.join(" + ")));
+            }
+        } else {
+            // Avoid suggesting the following:
+            // fn foo<T, <T as Trait>::Bar>(_: T) where T: Trait, <T as Trait>::Bar: Other {}
+            where_clauses.extend(
+                bounds.into_iter().map(|bound| format!("{}: {}", ty, tcx.def_path_str(bound))),
+            );
+        }
     }
+
+    let generics =
+        if types_str.is_empty() { "".to_string() } else { format!("<{}>", types_str.join(", ")) };
+
     let where_clauses = if where_clauses.is_empty() {
-        String::new()
+        "".to_string()
     } else {
         format!(" where {}", where_clauses.join(", "))
     };
+
     (generics, where_clauses)
 }
 

compiler/rustc_smir/src/rustc_internal/mod.rs

@@ -86,6 +86,10 @@ impl<'tcx> Tables<'tcx> {
         stable_mir::ty::ImplDef(self.create_def_id(did))
     }
 
+    pub fn region_def(&mut self, did: DefId) -> stable_mir::ty::RegionDef {
+        stable_mir::ty::RegionDef(self.create_def_id(did))
+    }
+
     pub fn prov(&mut self, aid: AllocId) -> stable_mir::ty::Prov {
         stable_mir::ty::Prov(self.create_alloc_id(aid))
     }

compiler/rustc_smir/src/rustc_smir/mod.rs

@@ -7,7 +7,8 @@
 //!
 //! For now, we are developing everything inside `rustc`, thus, we keep this module private.
 
-use hir::def::DefKind;
+use crate::rustc_smir::hir::def::DefKind;
+use crate::rustc_smir::stable_mir::ty::{BoundRegion, EarlyBoundRegion, Region};
 use rustc_hir as hir;
 use rustc_middle::mir;
 use rustc_middle::mir::interpret::{alloc_range, AllocId};
@@ -1500,9 +1501,39 @@ impl<'tcx> Stable<'tcx> for ty::ImplPolarity {
 impl<'tcx> Stable<'tcx> for ty::Region<'tcx> {
     type T = stable_mir::ty::Region;
 
-    fn stable(&self, _: &mut Tables<'tcx>) -> Self::T {
-        // FIXME: add a real implementation of stable regions
-        opaque(self)
+    fn stable(&self, tables: &mut Tables<'tcx>) -> Self::T {
+        Region { kind: self.kind().stable(tables) }
+    }
+}
+
+impl<'tcx> Stable<'tcx> for ty::RegionKind<'tcx> {
+    type T = stable_mir::ty::RegionKind;
+
+    fn stable(&self, tables: &mut Tables<'tcx>) -> Self::T {
+        use stable_mir::ty::RegionKind;
+        match self {
+            ty::ReEarlyBound(early_reg) => RegionKind::ReEarlyBound(EarlyBoundRegion {
+                def_id: tables.region_def(early_reg.def_id),
+                index: early_reg.index,
+                name: early_reg.name.to_string(),
+            }),
+            ty::ReLateBound(db_index, bound_reg) => RegionKind::ReLateBound(
+                db_index.as_u32(),
+                BoundRegion { var: bound_reg.var.as_u32(), kind: bound_reg.kind.stable(tables) },
+            ),
+            ty::ReStatic => RegionKind::ReStatic,
+            ty::RePlaceholder(place_holder) => {
+                RegionKind::RePlaceholder(stable_mir::ty::Placeholder {
+                    universe: place_holder.universe.as_u32(),
+                    bound: BoundRegion {
+                        var: place_holder.bound.var.as_u32(),
+                        kind: place_holder.bound.kind.stable(tables),
+                    },
+                })
+            }
+            ty::ReErased => RegionKind::ReErased,
+            _ => unreachable!("{self:?}"),
+        }
     }
 }
 

compiler/stable_mir/src/fold.rs

@@ -4,17 +4,20 @@ use crate::Opaque;
 
 use super::ty::{
     Allocation, Binder, Const, ConstDef, ConstantKind, ExistentialPredicate, FnSig, GenericArgKind,
-    GenericArgs, Promoted, RigidTy, TermKind, Ty, TyKind, UnevaluatedConst,
+    GenericArgs, Promoted, Region, RigidTy, TermKind, Ty, TyKind, UnevaluatedConst,
 };
 
 pub trait Folder: Sized {
     type Break;
-    fn visit_ty(&mut self, ty: &Ty) -> ControlFlow<Self::Break, Ty> {
+    fn fold_ty(&mut self, ty: &Ty) -> ControlFlow<Self::Break, Ty> {
         ty.super_fold(self)
     }
     fn fold_const(&mut self, c: &Const) -> ControlFlow<Self::Break, Const> {
         c.super_fold(self)
     }
+    fn fold_reg(&mut self, reg: &Region) -> ControlFlow<Self::Break, Region> {
+        reg.super_fold(self)
+    }
 }
 
 pub trait Foldable: Sized + Clone {
@@ -26,7 +29,7 @@ pub trait Foldable: Sized + Clone {
 
 impl Foldable for Ty {
     fn fold<V: Folder>(&self, folder: &mut V) -> ControlFlow<V::Break, Self> {
-        folder.visit_ty(self)
+        folder.fold_ty(self)
     }
     fn super_fold<V: Folder>(&self, folder: &mut V) -> ControlFlow<V::Break, Self> {
         let mut kind = self.kind();
@@ -106,6 +109,15 @@ impl Foldable for GenericArgs {
     }
 }
 
+impl Foldable for Region {
+    fn fold<V: Folder>(&self, folder: &mut V) -> ControlFlow<V::Break, Self> {
+        folder.fold_reg(self)
+    }
+    fn super_fold<V: Folder>(&self, _: &mut V) -> ControlFlow<V::Break, Self> {
+        ControlFlow::Continue(self.clone())
+    }
+}
+
 impl Foldable for GenericArgKind {
     fn super_fold<V: Folder>(&self, folder: &mut V) -> ControlFlow<V::Break, Self> {
         let mut this = self.clone();
@@ -136,7 +148,10 @@ impl Foldable for RigidTy {
             }
             RigidTy::Slice(inner) => *inner = inner.fold(folder)?,
             RigidTy::RawPtr(ty, _) => *ty = ty.fold(folder)?,
-            RigidTy::Ref(_, ty, _) => *ty = ty.fold(folder)?,
+            RigidTy::Ref(reg, ty, _) => {
+                *reg = reg.fold(folder)?;
+                *ty = ty.fold(folder)?
+            }
             RigidTy::FnDef(_, args) => *args = args.fold(folder)?,
             RigidTy::FnPtr(sig) => *sig = sig.fold(folder)?,
             RigidTy::Closure(_, args) => *args = args.fold(folder)?,
@@ -214,7 +229,7 @@ pub enum Never {}
 impl Folder for GenericArgs {
     type Break = Never;
 
-    fn visit_ty(&mut self, ty: &Ty) -> ControlFlow<Self::Break, Ty> {
+    fn fold_ty(&mut self, ty: &Ty) -> ControlFlow<Self::Break, Ty> {
         ControlFlow::Continue(match ty.kind() {
             TyKind::Param(p) => self[p],
             _ => *ty,

compiler/stable_mir/src/ty.rs

@@ -1,7 +1,7 @@
 use super::{
     mir::Safety,
     mir::{Body, Mutability},
-    with, AllocId, DefId,
+    with, AllocId, DefId, Symbol,
 };
 use crate::Opaque;
 use std::fmt::{self, Debug, Formatter};
@@ -34,7 +34,46 @@ pub struct Const {
 }
 
 type Ident = Opaque;
-pub type Region = Opaque;
+
+#[derive(Debug, Clone)]
+pub struct Region {
+    pub kind: RegionKind,
+}
+
+#[derive(Debug, Clone)]
+pub enum RegionKind {
+    ReEarlyBound(EarlyBoundRegion),
+    ReLateBound(DebruijnIndex, BoundRegion),
+    ReStatic,
+    RePlaceholder(Placeholder<BoundRegion>),
+    ReErased,
+}
+
+pub(crate) type DebruijnIndex = u32;
+
+#[derive(Debug, Clone)]
+pub struct EarlyBoundRegion {
+    pub def_id: RegionDef,
+    pub index: u32,
+    pub name: Symbol,
+}
+
+pub(crate) type BoundVar = u32;
+
+#[derive(Debug, Clone)]
+pub struct BoundRegion {
+    pub var: BoundVar,
+    pub kind: BoundRegionKind,
+}
+
+pub(crate) type UniverseIndex = u32;
+
+#[derive(Debug, Clone)]
+pub struct Placeholder<T> {
+    pub universe: UniverseIndex,
+    pub bound: T,
+}
+
 #[derive(Clone, Copy, PartialEq, Eq)]
 pub struct Span(pub usize);
 
@@ -152,6 +191,9 @@ pub struct ConstDef(pub DefId);
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct ImplDef(pub DefId);
 
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct RegionDef(pub DefId);
+
 #[derive(Clone, Debug)]
 pub struct GenericArgs(pub Vec<GenericArgKind>);
 

compiler/stable_mir/src/visitor.rs

@@ -4,7 +4,7 @@ use crate::Opaque;
 
 use super::ty::{
     Allocation, Binder, Const, ConstDef, ExistentialPredicate, FnSig, GenericArgKind, GenericArgs,
-    Promoted, RigidTy, TermKind, Ty, UnevaluatedConst,
+    Promoted, Region, RigidTy, TermKind, Ty, UnevaluatedConst,
 };
 
 pub trait Visitor: Sized {
@@ -15,6 +15,9 @@ pub trait Visitor: Sized {
     fn visit_const(&mut self, c: &Const) -> ControlFlow<Self::Break> {
         c.super_visit(self)
     }
+    fn visit_reg(&mut self, reg: &Region) -> ControlFlow<Self::Break> {
+        reg.super_visit(self)
+    }
 }
 
 pub trait Visitable {
@@ -101,6 +104,16 @@ impl Visitable for GenericArgs {
     }
 }
 
+impl Visitable for Region {
+    fn visit<V: Visitor>(&self, visitor: &mut V) -> ControlFlow<V::Break> {
+        visitor.visit_reg(self)
+    }
+
+    fn super_visit<V: Visitor>(&self, _: &mut V) -> ControlFlow<V::Break> {
+        ControlFlow::Continue(())
+    }
+}
+
 impl Visitable for GenericArgKind {
     fn super_visit<V: Visitor>(&self, visitor: &mut V) -> ControlFlow<V::Break> {
         match self {
@@ -128,7 +141,10 @@ impl Visitable for RigidTy {
             }
             RigidTy::Slice(inner) => inner.visit(visitor),
             RigidTy::RawPtr(ty, _) => ty.visit(visitor),
-            RigidTy::Ref(_, ty, _) => ty.visit(visitor),
+            RigidTy::Ref(reg, ty, _) => {
+                reg.visit(visitor);
+                ty.visit(visitor)
+            }
             RigidTy::FnDef(_, args) => args.visit(visitor),
             RigidTy::FnPtr(sig) => sig.visit(visitor),
             RigidTy::Closure(_, args) => args.visit(visitor),

library/core/src/sync/exclusive.rs

@@ -2,6 +2,8 @@
 
 use core::fmt;
 use core::future::Future;
+use core::marker::Tuple;
+use core::ops::{Generator, GeneratorState};
 use core::pin::Pin;
 use core::task::{Context, Poll};
 
@@ -168,10 +170,52 @@ impl<T> From<T> for Exclusive<T> {
 }
 
 #[unstable(feature = "exclusive_wrapper", issue = "98407")]
-impl<T: Future + ?Sized> Future for Exclusive<T> {
+impl<F, Args> FnOnce<Args> for Exclusive<F>
+where
+    F: FnOnce<Args>,
+    Args: Tuple,
+{
+    type Output = F::Output;
+
+    extern "rust-call" fn call_once(self, args: Args) -> Self::Output {
+        self.into_inner().call_once(args)
+    }
+}
+
+#[unstable(feature = "exclusive_wrapper", issue = "98407")]
+impl<F, Args> FnMut<Args> for Exclusive<F>
+where
+    F: FnMut<Args>,
+    Args: Tuple,
+{
+    extern "rust-call" fn call_mut(&mut self, args: Args) -> Self::Output {
+        self.get_mut().call_mut(args)
+    }
+}
+
+#[unstable(feature = "exclusive_wrapper", issue = "98407")]
+impl<T> Future for Exclusive<T>
+where
+    T: Future + ?Sized,
+{
     type Output = T::Output;
+
     #[inline]
     fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         self.get_pin_mut().poll(cx)
     }
 }
+
+#[unstable(feature = "generator_trait", issue = "43122")] // also #98407
+impl<R, G> Generator<R> for Exclusive<G>
+where
+    G: Generator<R> + ?Sized,
+{
+    type Yield = G::Yield;
+    type Return = G::Return;
+
+    #[inline]
+    fn resume(self: Pin<&mut Self>, arg: R) -> GeneratorState<Self::Yield, Self::Return> {
+        G::resume(self.get_pin_mut(), arg)
+    }
+}