diff --git a/compiler/rustc_smir/src/rustc_internal/mod.rs b/compiler/rustc_smir/src/rustc_internal/mod.rs
index 527d5220564cc..d32215186a63d 100644
--- a/compiler/rustc_smir/src/rustc_internal/mod.rs
+++ b/compiler/rustc_smir/src/rustc_internal/mod.rs
@@ -31,6 +31,18 @@ pub fn adt_def(did: DefId) -> stable_mir::ty::AdtDef {
     with_tables(|t| t.adt_def(did))
 }
 
+pub fn foreign_def(did: DefId) -> stable_mir::ty::ForeignDef {
+    with_tables(|t| t.foreign_def(did))
+}
+
+pub fn fn_def(did: DefId) -> stable_mir::ty::FnDef {
+    with_tables(|t| t.fn_def(did))
+}
+
+pub fn closure_def(did: DefId) -> stable_mir::ty::ClosureDef {
+    with_tables(|t| t.closure_def(did))
+}
+
 impl<'tcx> Tables<'tcx> {
     pub fn item_def_id(&self, item: &stable_mir::CrateItem) -> DefId {
         self.def_ids[item.0]
@@ -44,6 +56,18 @@ impl<'tcx> Tables<'tcx> {
         stable_mir::ty::AdtDef(self.create_def_id(did))
     }
 
+    pub fn foreign_def(&mut self, did: DefId) -> stable_mir::ty::ForeignDef {
+        stable_mir::ty::ForeignDef(self.create_def_id(did))
+    }
+
+    pub fn fn_def(&mut self, did: DefId) -> stable_mir::ty::FnDef {
+        stable_mir::ty::FnDef(self.create_def_id(did))
+    }
+
+    pub fn closure_def(&mut self, did: DefId) -> stable_mir::ty::ClosureDef {
+        stable_mir::ty::ClosureDef(self.create_def_id(did))
+    }
+
     fn create_def_id(&mut self, did: DefId) -> stable_mir::DefId {
         // FIXME: this becomes inefficient when we have too many ids
         for (i, &d) in self.def_ids.iter().enumerate() {
diff --git a/compiler/rustc_smir/src/rustc_smir/mod.rs b/compiler/rustc_smir/src/rustc_smir/mod.rs
index 0e5de1e74d32d..daa1b1ebb9a43 100644
--- a/compiler/rustc_smir/src/rustc_smir/mod.rs
+++ b/compiler/rustc_smir/src/rustc_smir/mod.rs
@@ -8,7 +8,7 @@
 //! For now, we are developing everything inside `rustc`, thus, we keep this module private.
 
 use crate::rustc_internal::{self, opaque};
-use crate::stable_mir::ty::{AdtSubsts, FloatTy, GenericArgKind, IntTy, RigidTy, TyKind, UintTy};
+use crate::stable_mir::ty::{FloatTy, GenericArgKind, GenericArgs, IntTy, RigidTy, TyKind, UintTy};
 use crate::stable_mir::{self, Context};
 use rustc_middle::mir;
 use rustc_middle::ty::{self, Ty, TyCtxt};
@@ -96,7 +96,7 @@ impl<'tcx> Tables<'tcx> {
             },
             ty::Adt(adt_def, substs) => TyKind::RigidTy(RigidTy::Adt(
                 rustc_internal::adt_def(adt_def.did()),
-                AdtSubsts(
+                GenericArgs(
                     substs
                         .iter()
                         .map(|arg| match arg.unpack() {
@@ -113,7 +113,9 @@ impl<'tcx> Tables<'tcx> {
                         .collect(),
                 ),
             )),
-            ty::Foreign(_) => todo!(),
+            ty::Foreign(def_id) => {
+                TyKind::RigidTy(RigidTy::Foreign(rustc_internal::foreign_def(*def_id)))
+            }
             ty::Str => TyKind::RigidTy(RigidTy::Str),
             ty::Array(ty, constant) => {
                 TyKind::RigidTy(RigidTy::Array(self.intern_ty(*ty), opaque(constant)))
@@ -125,12 +127,48 @@ impl<'tcx> Tables<'tcx> {
             ty::Ref(region, ty, mutbl) => {
                 TyKind::RigidTy(RigidTy::Ref(opaque(region), self.intern_ty(*ty), mutbl.stable()))
             }
-            ty::FnDef(_, _) => todo!(),
+            ty::FnDef(def_id, generic_args) => TyKind::RigidTy(RigidTy::FnDef(
+                rustc_internal::fn_def(*def_id),
+                GenericArgs(
+                    generic_args
+                        .iter()
+                        .map(|arg| match arg.unpack() {
+                            ty::GenericArgKind::Lifetime(region) => {
+                                GenericArgKind::Lifetime(opaque(&region))
+                            }
+                            ty::GenericArgKind::Type(ty) => {
+                                GenericArgKind::Type(self.intern_ty(ty))
+                            }
+                            ty::GenericArgKind::Const(const_) => {
+                                GenericArgKind::Const(opaque(&const_))
+                            }
+                        })
+                        .collect(),
+                ),
+            )),
             ty::FnPtr(_) => todo!(),
             ty::Dynamic(_, _, _) => todo!(),
-            ty::Closure(_, _) => todo!(),
+            ty::Closure(def_id, generic_args) => TyKind::RigidTy(RigidTy::Closure(
+                rustc_internal::closure_def(*def_id),
+                GenericArgs(
+                    generic_args
+                        .iter()
+                        .map(|arg| match arg.unpack() {
+                            ty::GenericArgKind::Lifetime(region) => {
+                                GenericArgKind::Lifetime(opaque(&region))
+                            }
+                            ty::GenericArgKind::Type(ty) => {
+                                GenericArgKind::Type(self.intern_ty(ty))
+                            }
+                            ty::GenericArgKind::Const(const_) => {
+                                GenericArgKind::Const(opaque(&const_))
+                            }
+                        })
+                        .collect(),
+                ),
+            )),
             ty::Generator(_, _, _) => todo!(),
-            ty::Never => todo!(),
+            ty::Never => TyKind::RigidTy(RigidTy::Never),
             ty::Tuple(fields) => TyKind::RigidTy(RigidTy::Tuple(
                 fields.iter().map(|ty| self.intern_ty(ty)).collect(),
             )),
diff --git a/compiler/rustc_smir/src/stable_mir/ty.rs b/compiler/rustc_smir/src/stable_mir/ty.rs
index 7ae07efb729dd..758e0bb7de70d 100644
--- a/compiler/rustc_smir/src/stable_mir/ty.rs
+++ b/compiler/rustc_smir/src/stable_mir/ty.rs
@@ -25,12 +25,16 @@ pub enum RigidTy {
     Int(IntTy),
     Uint(UintTy),
     Float(FloatTy),
-    Adt(AdtDef, AdtSubsts),
+    Adt(AdtDef, GenericArgs),
+    Foreign(ForeignDef),
     Str,
     Array(Ty, Const),
     Slice(Ty),
     RawPtr(Ty, Mutability),
     Ref(Region, Ty, Mutability),
+    FnDef(FnDef, GenericArgs),
+    Closure(ClosureDef, GenericArgs),
+    Never,
     Tuple(Vec<Ty>),
 }
 
@@ -60,11 +64,20 @@ pub enum FloatTy {
     F64,
 }
 
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct ForeignDef(pub(crate) DefId);
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct FnDef(pub(crate) DefId);
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct ClosureDef(pub(crate) DefId);
+
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct AdtDef(pub(crate) DefId);
 
 #[derive(Clone, Debug)]
-pub struct AdtSubsts(pub Vec<GenericArgKind>);
+pub struct GenericArgs(pub Vec<GenericArgKind>);
 
 #[derive(Clone, Debug)]
 pub enum GenericArgKind {