diff --git a/imperative/python/test/unit/test_distributed.py b/imperative/python/test/unit/test_distributed.py
index dd5add7e5c529fa87d492dbb5a735777b14c1ee5..f81b9f42203c00f8932eaab14feba8098a935e9b 100644
--- a/imperative/python/test/unit/test_distributed.py
+++ b/imperative/python/test/unit/test_distributed.py
@@ -14,6 +14,7 @@ import pytest
 
 import megengine as mge
 import megengine.distributed as dist
+from megengine.core.ops.builtin import CollectiveComm, ParamPackConcat, ParamPackSplit
 from megengine.distributed.helper import get_device_count_by_fork
 
 
@@ -187,3 +188,10 @@ def test_synchronized():
     for p in procs:
         p.join(20)
         assert p.exitcode == 0
+
+
+def test_oprmm_hashable():
+    lhs = (CollectiveComm(), ParamPackConcat(), ParamPackSplit())
+    rhs = (CollectiveComm(), ParamPackConcat(), ParamPackSplit())
+    assert lhs == rhs
+    assert hash(lhs) == hash(rhs)
diff --git a/imperative/src/impl/ops/collective_comm.cpp b/imperative/src/impl/ops/collective_comm.cpp
index 4c23be99fd309ac47346f686c14fa64c6018f821..68a97bbb5fbc98c20f2bcdfcb92f2ed92a5e4d60 100644
--- a/imperative/src/impl/ops/collective_comm.cpp
+++ b/imperative/src/impl/ops/collective_comm.cpp
@@ -71,7 +71,7 @@ OP_TRAIT_REG(CollectiveComm, CollectiveComm, opr::CollectiveComm)
     .make_from_op_node(make_from_op_node)
     .fallback();
 } // anonymous namespace
-
+#endif // MGB_ENABLE_OPR_MM
 
 bool CollectiveComm::is_same_st(const Hashable& another) const{
     auto* comm_opr = another.try_cast_final<CollectiveComm>();
@@ -100,18 +100,6 @@ size_t CollectiveComm::hash() const{
     return xxhash.digest();
 }
 
-#else
-
-bool CollectiveComm::is_same_st(const Hashable& another) const{
-    return OpDef::is_same_st(another);
-}
-
-size_t CollectiveComm::hash() const{
-    return OpDef::hash();
-}
-
-#endif // MGB_ENABLE_OPR_MM
-
 MGB_DYN_TYPE_OBJ_FINAL_IMPL(CollectiveComm);
 
 }  // namespace imperative
diff --git a/imperative/src/include/megbrain/imperative/ops/tensor_manip.h b/imperative/src/include/megbrain/imperative/ops/tensor_manip.h
index 23a5bc31d20233b42d2a1830a62bef6d779df10f..8d3d44d38347de2b320e80d309fabbcb7cf14db4 100644
--- a/imperative/src/include/megbrain/imperative/ops/tensor_manip.h
+++ b/imperative/src/include/megbrain/imperative/ops/tensor_manip.h
@@ -64,11 +64,8 @@ public:
     }
 
     bool is_same_st(const Hashable& rhs) const override {
-        auto* pps = rhs.try_cast_final<ParamPackSplit>();
-        if(pps == nullptr){
-            return false;
-        }
-        return offsets == pps->offsets && shapes == pps->shapes;
+        auto&& pps = rhs.cast_final_safe<ParamPackSplit>();
+        return offsets == pps.offsets && shapes == pps.shapes;
     }
 };
 
@@ -94,11 +91,8 @@ public:
     }
 
     bool is_same_st(const Hashable& rhs) const override {
-        auto* ppc = rhs.try_cast_final<ParamPackConcat>();
-        if(ppc == nullptr){
-            return false;
-        }
-        return offsets == ppc->offsets;
+        auto&& ppc = rhs.cast_final_safe<ParamPackConcat>();
+        return offsets == ppc.offsets;
     }
 };