From c5c38cdee80e42c374a0afddeb843851abfd105b Mon Sep 17 00:00:00 2001
From: Santiago Pastorino <spastorino@gmail.com>
Date: Tue, 18 Jul 2023 12:19:41 -0300
Subject: [PATCH] Add Closure ty to SMIR

---
 compiler/rustc_smir/src/rustc_internal/mod.rs |  8 ++++++++
 compiler/rustc_smir/src/rustc_smir/mod.rs     | 20 ++++++++++++++++++-
 compiler/rustc_smir/src/stable_mir/ty.rs      |  4 ++++
 3 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/compiler/rustc_smir/src/rustc_internal/mod.rs b/compiler/rustc_smir/src/rustc_internal/mod.rs
index e4f129bc1d6..d32215186a6 100644
--- a/compiler/rustc_smir/src/rustc_internal/mod.rs
+++ b/compiler/rustc_smir/src/rustc_internal/mod.rs
@@ -39,6 +39,10 @@ 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]
@@ -60,6 +64,10 @@ 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 81ca0f985cc..b542cc84f6a 100644
--- a/compiler/rustc_smir/src/rustc_smir/mod.rs
+++ b/compiler/rustc_smir/src/rustc_smir/mod.rs
@@ -148,7 +148,25 @@ fn rustc_ty_to_ty(&mut self, ty: Ty<'tcx>) -> TyKind {
             )),
             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 => TyKind::RigidTy(RigidTy::Never),
             ty::Tuple(fields) => TyKind::RigidTy(RigidTy::Tuple(
diff --git a/compiler/rustc_smir/src/stable_mir/ty.rs b/compiler/rustc_smir/src/stable_mir/ty.rs
index f3dbde907a0..758e0bb7de7 100644
--- a/compiler/rustc_smir/src/stable_mir/ty.rs
+++ b/compiler/rustc_smir/src/stable_mir/ty.rs
@@ -33,6 +33,7 @@ pub enum RigidTy {
     RawPtr(Ty, Mutability),
     Ref(Region, Ty, Mutability),
     FnDef(FnDef, GenericArgs),
+    Closure(ClosureDef, GenericArgs),
     Never,
     Tuple(Vec<Ty>),
 }
@@ -69,6 +70,9 @@ pub enum FloatTy {
 #[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);