Add stable Instance::body() and RustcInternal trait

The `Instance::body()` returns a monomorphized body.

For that, we had to implement visitor that monomorphize types and
constants. We are also introducing the RustcInternal trait that will
allow us to convert back from Stable to Internal.

Note that this trait is not yet visible for our users as it depends on
Tables. We should probably add a new trait that can be exposed.

1 files changed, 10 insertions, 0 deletions

diff --git a/compiler/rustc_smir/src/rustc_internal/mod.rs b/compiler/rustc_smir/src/rustc_internal/mod.rs
index 5ea805e5739..473a59f750a 100644
--- a/compiler/rustc_smir/src/rustc_internal/mod.rs
+++ b/compiler/rustc_smir/src/rustc_internal/mod.rs
@@ -20,6 +20,8 @@ use std::fmt::Debug;
 use std::hash::Hash;
 use std::ops::{ControlFlow, Index};
 
+mod internal;
+
 impl<'tcx> Index<stable_mir::DefId> for Tables<'tcx> {
     type Output = DefId;
 
@@ -231,3 +233,11 @@ impl<K: PartialEq + Hash + Eq, V: Copy + Debug + PartialEq + IndexedVal> Index<V
         k
     }
 }
+
+/// Trait used to translate a stable construct to its rustc counterpart.
+///
+/// This is basically a mirror of [crate::rustc_smir::Stable].
+pub(crate) trait RustcInternal<'tcx> {
+    type T;
+    fn internal(&self, tables: &mut Tables<'tcx>) -> Self::T;
+}