Implement UtilitiesInstructions, CondSwapInstructions for MerkleChip

Author: therealyingtong

src/circuit/gadget/orchard_action/merkle.rs

@@ -165,3 +165,37 @@ impl<C: CurveAffine, const PATH_LENGTH: usize, const K: usize, const MAX_WORDS:
         SinsemillaChip::<C, K, MAX_WORDS>::extract(point)
     }
 }
+
+impl<C: CurveAffine, const PATH_LENGTH: usize, const K: usize, const MAX_WORDS: usize>
+    UtilitiesInstructions<C::Base> for MerkleChip<C, PATH_LENGTH, K, MAX_WORDS>
+{
+    type Var = CellValue<C::Base>;
+}
+
+impl<C: CurveAffine, const PATH_LENGTH: usize, const K: usize, const MAX_WORDS: usize>
+    CondSwapInstructions<C::Base> for MerkleChip<C, PATH_LENGTH, K, MAX_WORDS>
+{
+    type Var = CellValue<C::Base>;
+    type Swap = Swap;
+
+    #[allow(clippy::type_complexity)]
+    fn swap(
+        &self,
+        layouter: impl Layouter<C::Base>,
+        pair: (
+            <Self as CondSwapInstructions<C::Base>>::Var,
+            <Self as CondSwapInstructions<C::Base>>::Var,
+        ),
+        swap: Self::Swap,
+    ) -> Result<
+        (
+            <Self as CondSwapInstructions<C::Base>>::Var,
+            <Self as CondSwapInstructions<C::Base>>::Var,
+        ),
+        Error,
+    > {
+        let config = self.config().cond_swap_config.clone();
+        let chip = CondSwapChip::<C::Base>::construct(config);
+        chip.swap(layouter, pair, swap)
+    }
+}