Implement Stable for Discr

Author: NotLebedev

compiler/rustc_smir/src/rustc_smir/context.rs

@@ -445,12 +445,9 @@ impl<'tcx> SmirCtxt<'tcx> {
     pub fn adt_discr_for_variant(&self, adt: AdtDef, variant: VariantIdx) -> Discr {
         let mut tables = self.0.borrow_mut();
         let tcx = tables.tcx;
-
-        let discr = adt
-            .internal(&mut *tables, tcx)
-            .discriminant_for_variant(tcx, variant.internal(&mut *tables, tcx));
-
-        Discr { val: discr.val, ty: discr.ty.stable(&mut *tables) }
+        let adt = adt.internal(&mut *tables, tcx);
+        let variant = variant.internal(&mut *tables, tcx);
+        adt.discriminant_for_variant(tcx, variant).stable(&mut *tables)
     }
 
     /// Discriminant for a given variand index and args of a coroutine
@@ -462,14 +459,10 @@ impl<'tcx> SmirCtxt<'tcx> {
     ) -> Discr {
         let mut tables = self.0.borrow_mut();
         let tcx = tables.tcx;
-
-        let discr = args.internal(&mut *tables, tcx).as_coroutine().discriminant_for_variant(
-            coroutine.def_id().internal(&mut *tables, tcx),
-            tcx,
-            variant.internal(&mut *tables, tcx),
-        );
-
-        Discr { val: discr.val, ty: discr.ty.stable(&mut *tables) }
+        let coroutine = coroutine.def_id().internal(&mut *tables, tcx);
+        let args = args.internal(&mut *tables, tcx);
+        let variant = variant.internal(&mut *tables, tcx);
+        args.as_coroutine().discriminant_for_variant(coroutine, tcx, variant).stable(&mut *tables)
     }
 
     /// The name of a variant.

compiler/rustc_smir/src/rustc_smir/convert/ty.rs

@@ -959,3 +959,11 @@ impl<'tcx> Stable<'tcx> for ty::ImplTraitInTraitData {
         }
     }
 }
+
+impl<'tcx> Stable<'tcx> for rustc_middle::ty::util::Discr<'tcx> {
+    type T = stable_mir::ty::Discr;
+
+    fn stable(&self, tables: &mut Tables<'_>) -> Self::T {
+        stable_mir::ty::Discr { val: self.val, ty: self.ty.stable(tables) }
+    }
+}