Add Bound ty to SMIR

compiler/rustc_smir/src/rustc_smir/mod.rs

@@ -826,7 +826,9 @@ fn stable(&self, tables: &mut Tables<'tcx>) -> Self::T {
                 TyKind::Alias(alias_kind.stable(tables), alias_ty.stable(tables))
             }
             ty::Param(param_ty) => TyKind::Param(param_ty.stable(tables)),
-            ty::Bound(_, _) => todo!(),
+            ty::Bound(debruijn_idx, bound_ty) => {
+                TyKind::Bound(debruijn_idx.as_usize(), bound_ty.stable(tables))
+            }
             ty::Placeholder(..)
             | ty::GeneratorWitness(_)
             | ty::GeneratorWitnessMIR(_, _)
@@ -845,3 +847,11 @@ fn stable(&self, _: &mut Tables<'tcx>) -> Self::T {
         ParamTy { index: self.index, name: self.name.to_string() }
     }
 }
+
+impl<'tcx> Stable<'tcx> for rustc_middle::ty::BoundTy {
+    type T = stable_mir::ty::BoundTy;
+    fn stable(&self, tables: &mut Tables<'tcx>) -> Self::T {
+        use stable_mir::ty::BoundTy;
+        BoundTy { var: self.var.as_usize(), kind: self.kind.stable(tables) }
+    }
+}

compiler/rustc_smir/src/stable_mir/ty.rs

@@ -19,6 +19,7 @@ pub enum TyKind {
     RigidTy(RigidTy),
     Alias(AliasKind, AliasTy),
     Param(ParamTy),
+    Bound(usize, BoundTy),
 }
 
 #[derive(Clone, Debug)]
@@ -235,3 +236,9 @@ pub struct ParamTy {
     pub index: u32,
     pub name: String,
 }
+
+#[derive(Clone, Debug)]
+pub struct BoundTy {
+    pub var: usize,
+    pub kind: BoundTyKind,
+}