diff --git a/modules/Nncase.Modules.CPU/CodeGen/CPU/CSourceBuiltn.cs b/modules/Nncase.Modules.CPU/CodeGen/CPU/CSourceBuiltn.cs
index 85441998bf..9f8bd17ff9 100644
--- a/modules/Nncase.Modules.CPU/CodeGen/CPU/CSourceBuiltn.cs
+++ b/modules/Nncase.Modules.CPU/CodeGen/CPU/CSourceBuiltn.cs
@@ -40,7 +40,7 @@ public static class CSourceBuiltn
 #include <nncase/ntt/ntt.h>
 using namespace nncase::ntt;
 using namespace nncase::ntt::distributed;
-using namespace nncase::ntt::distributed::dist_policy;
+using namespace nncase::ntt::distributed::shard_policy;
 
 ";
 
diff --git a/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelCSourceConvertVisitor.cs b/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelCSourceConvertVisitor.cs
index b67ca8c90d..2ba6e5135a 100644
--- a/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelCSourceConvertVisitor.cs
+++ b/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelCSourceConvertVisitor.cs
@@ -526,7 +526,11 @@ protected override CSymbol VisitCall(Call expr)
 #if DEBUG_PRINT
             IndentScope.Writer.IndWrite($"runtime_util->printf(\"call {deviceFunc.Name} bid %d tid %d\\n\", bid, tid);\n");
 #endif
-            var arguments = expr.Arguments.AsValueEnumerable().Select(Visit).ToArray();
+            var arguments = expr.Arguments.AsValueEnumerable().Select(x => x switch
+            {
+                TIR.Buffer b => VisitBuffer(b, local: true),
+                _ => Visit(x),
+            }).ToArray();
             _refFuncs.Add(deviceFunc);
             IndentScope.Writer.IndWrite($"{deviceFunc.Name}({string.Join(",", arguments.Select(arg => arg.Name))});\n");
         }
diff --git a/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelUtility.cs b/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelUtility.cs
index 4084888032..84c249313c 100644
--- a/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelUtility.cs
+++ b/modules/Nncase.Modules.CPU/CodeGen/CPU/KernelUtility.cs
@@ -80,8 +80,8 @@ public static string DistributedToC(DistributedType distributedType)
             }
         }
 
-        var nonAxisPolicy = ndSBP.Any(x => x is SBPPartialSum) ? "P" : "B";
-        sb.Append('>');
+        var implicitPolicy = ndSBP.Any(x => x is SBPPartialSum) ? "P<reduce_op::sum>" : "B";
+        sb.Append($">, {implicitPolicy}");
 
         for (int axis = 0; axis < distributedType.TensorType.Shape.Rank; axis++)
         {
@@ -94,7 +94,7 @@ public static string DistributedToC(DistributedType distributedType)
             }
             else
             {
-                sb.Append($", {nonAxisPolicy}");
+                sb.Append($", I");
             }
         }
 
diff --git a/ntt/include/nncase/ntt/sharding.h b/ntt/include/nncase/ntt/sharding.h
index d98cec698d..57757a466d 100644
--- a/ntt/include/nncase/ntt/sharding.h
+++ b/ntt/include/nncase/ntt/sharding.h
@@ -18,9 +18,17 @@
 #include "shape.h"
 
 namespace nncase::ntt::distributed {
-namespace dist_policy {
+namespace shard_policy {
 // Broadcast
-struct B {
+struct B {};
+
+// Partial
+template <reduce_op ReduceOp> struct P {
+    static constexpr ntt::reduce_op reduce_op = ReduceOp;
+};
+
+// Implicit
+struct I {
     template <class Mesh>
     static constexpr size_t local_dim(size_t global_dim) noexcept {
         return global_dim;
@@ -37,15 +45,7 @@ template <size_t... Axes> struct S {
         return ntt::ceil_div(global_dim, divider);
     }
 };
-
-// Partial
-struct P {
-    template <class Mesh>
-    static constexpr size_t local_dim(size_t global_dim) noexcept {
-        return global_dim;
-    }
-};
-} // namespace dist_policy
+} // namespace shard_policy
 
 template <topology Scope, size_t... Dims> struct mesh {
     using shape_type = fixed_shape<Dims...>;
@@ -57,11 +57,13 @@ template <topology Scope, size_t... Dims> struct mesh {
     remote_program_id(ranked_shape<shape_type::rank()> index) noexcept;
 };
 
-template <class Mesh, class... Policies> struct sharding {
+template <class Mesh, class ImplicitPolicy, class... AxisPolicies>
+struct sharding {
     using mesh_type = Mesh;
+    using implicit_policy_type = ImplicitPolicy;
+    using axis_policy_type = std::tuple<AxisPolicies...>;
 
-    static constexpr std::tuple<Policies...> policies = {Policies{}...};
-    static constexpr size_t policies_size = sizeof...(Policies);
+    static constexpr size_t axis_policies_size = sizeof...(AxisPolicies);
 };
 
 namespace detail {
@@ -103,11 +105,11 @@ constexpr size_t get_submesh_start() noexcept {
 
 template <class Sharding, size_t Axis, class GlobalShape>
 constexpr size_t get_local_shard_dim(GlobalShape shape) noexcept {
-    static_assert(GlobalShape::rank() == Sharding::policies_size,
+    static_assert(GlobalShape::rank() == Sharding::axis_policies_size,
                   "Invalid sharding.");
 
     auto local_dim = shape.at(Axis);
-    return std::get<Axis>(Sharding::policies)
+    return std::get<Axis>(typename Sharding::axis_policy_type{})
         .template local_dim<typename Sharding::mesh_type>(local_dim);
 }