diff --git a/dnn/scripts/gen_tablegen.py b/dnn/scripts/gen_tablegen.py
index 751e7578..f1c174c3 100755
--- a/dnn/scripts/gen_tablegen.py
+++ b/dnn/scripts/gen_tablegen.py
@@ -11,6 +11,11 @@ import io
 
 from gen_param_defs import member_defs, ParamDef, IndentWriterBase
 
+# FIXME: move supportToString flag definition into the param def source file
+ENUM_TO_STRING_SPECIAL_RULES = [
+    ("Elemwise", "Mode"),
+    ("ElemwiseMultiType", "Mode")
+]
 
 class ConverterWriter(IndentWriterBase):
     _skip_current_param = False
@@ -86,7 +91,10 @@ class ConverterWriter(IndentWriterBase):
         def format(v):
             return '\"{}\"'.format(str(v))
         enum_def += ','.join(format(i) for i in e.members)
-        enum_def += "]>"
+        enum_def += "]"
+        if ENUM_TO_STRING_SPECIAL_RULES.count((p.name, e.name)):
+            enum_def += ", 1" # whether generate ToStringTrait
+        enum_def += ">"
         self._write("def {} : {};".format(td_class, enum_def))
 
         if self._skip_current_param:
diff --git a/imperative/src/include/megbrain/imperative/ops/autogen.h b/imperative/src/include/megbrain/imperative/ops/autogen.h
index 96e39a52..e2540278 100644
--- a/imperative/src/include/megbrain/imperative/ops/autogen.h
+++ b/imperative/src/include/megbrain/imperative/ops/autogen.h
@@ -12,6 +12,7 @@
 #pragma once
 
 #include "megbrain/imperative/op_def.h"
+#include "megbrain/imperative/utils/to_string.h"
 #include "megdnn/opr_param_defs.h"
 #include "megbrain/opr/param_defs.h"
 
diff --git a/imperative/tablegen/autogen.cpp b/imperative/tablegen/autogen.cpp
index a86788ad..eec1a5ec 100644
--- a/imperative/tablegen/autogen.cpp
+++ b/imperative/tablegen/autogen.cpp
@@ -179,6 +179,34 @@ static void gen_op_def_c_header_single(raw_ostream &os, MgbOp& op) {
     );
 }
 
+static void gen_to_string_trait_for_enum(raw_ostream &os, MgbOp& op) {
+    for (auto &&i : op.getMgbAttributes()) {
+        if (auto attr = llvm::dyn_cast<MgbEnumAttr>(&i.attr)) {
+            if (attr->supportToString()) {
+                std::vector<std::string> case_body;
+                std::string ename = formatv("{0}::{1}",
+                    op.getCppClassName(), attr->getEnumName());
+                llvm::for_each(attr->getEnumMembers(), [&](auto&& v){
+                    case_body.push_back(formatv(
+                        "case {0}::{1}: return \"{1}\";", ename, v));
+                });
+                os << formatv(R"(
+template <>
+struct ToStringTrait<{0}> {
+    std::string operator()({0} e) const {
+        switch (e) {
+            {1}
+            default:
+                return "{0}::Unknown";
+        }
+    }
+};
+)", ename, llvm::join(case_body, "\n"));
+            }
+        }
+    }
+}
+
 static void gen_op_def_c_body_single(raw_ostream &os, MgbOp& op) {
     auto&& className = op.getCppClassName();
     os << formatv(
@@ -241,7 +269,13 @@ static void gen_op_def_c_body_single(raw_ostream &os, MgbOp& op) {
         os << formatv(
             "std::string {0}(const OpDef& def_) {{\n", formatMethImpl("make_name")
         );
-        os << mlir::tblgen::tgfmt(hashable->getNameFunctionTemplate(), &ctx);
+        os << formatv(
+            "    auto&& op_ = def_.cast_final_safe<{0}>();\n"
+            "    static_cast<void>(op_);\n",
+            className
+        );
+        ctx.withSelf("op_");
+        os << mlir::tblgen::tgfmt(op.getNameFunctionTemplate(), &ctx);
         os << "}\n";
 
         os << "} // anonymous namespace\n";
@@ -577,6 +611,7 @@ static void for_each_operator(raw_ostream &os, RecordKeeper &keeper,
 
 static bool gen_op_def_c_header(raw_ostream &os, RecordKeeper &keeper) {
     for_each_operator(os, keeper, gen_op_def_c_header_single);
+    for_each_operator(os, keeper, gen_to_string_trait_for_enum);
     return false;
 }
 
diff --git a/imperative/tablegen/helper.h b/imperative/tablegen/helper.h
index 9145d387..c5f084e4 100644
--- a/imperative/tablegen/helper.h
+++ b/imperative/tablegen/helper.h
@@ -74,6 +74,9 @@ struct MgbEnumAttrMixin : public MgbAttrWrapperBase {
     std::vector<StringRef> getEnumMembers() const {
         return getBaseRecord()->getValueAsListOfStrings("enumMembers");
     }
+    bool supportToString() const {
+        return getBaseRecord()->getValueAsBit("supportToString");
+    }
 };
 
 struct MgbHashableAttrMixin : public MgbAttrWrapperBase {
@@ -170,6 +173,12 @@ public:
         }
         return ret;
     }
+    std::string getNameFunctionTemplate() const {
+        if (auto f = getDef().getValueAsOptionalString("nameFunction")) {
+            return f.getValue().str();
+        }
+        return formatv("    return \"{0}\";\n", getCppClassName());
+    }
 };
 
 struct MgbHashableOpMixin : public MgbOpBase {
@@ -241,30 +250,6 @@ private:
         body += "    return props_;\n";
         return body;
     }
-    std::string getModeName() const {
-        std::string body = formatv(
-            "    auto&& op_ = def_.cast_final_safe<{0}>();\n"
-            "    static_cast<void>(op_);\n",
-            getCppClassName()
-        );
-        for (auto&& it : getMgbAttributes()) {
-            if (it.name == "mode") {
-                auto* enumAttr = llvm::dyn_cast<MgbEnumAttrMixin>(&it.attr);
-                body += "    switch (op_.mode){\n";
-                for (auto&& enumMember: enumAttr->getEnumMembers()) {
-                    body += formatv(
-                        "        case {0}::{1}::{2}:\n",
-                        getCppClassName(), enumAttr->getEnumName(), enumMember
-                    );
-                    body += formatv("            return \"{0}\";\n", enumMember);
-                }
-                body += formatv(
-                    "        default: return \"{0}::Unknown\";\n", getCppClassName());
-                body += "    }\n";
-            }
-        }
-        return body;
-    }
 public:
     static bool classof(const Operator* op) {
         return op->getDef().isSubClassOf("MgbHashableOpMixin");
@@ -288,12 +273,6 @@ public:
         }
         return getDefaultPropsFunction();
     }
-    std::string getNameFunctionTemplate() const {
-        if (getDef().getValueAsBit("usingModeName")) {
-            return getModeName();
-        }
-        return formatv("    return \"{0}\";\n", getCppClassName());
-    }
 };
 
 } // namespace tblgen
diff --git a/src/core/include/megbrain/ir/base.td b/src/core/include/megbrain/ir/base.td
index 2b11392d..d1f35ebc 100644
--- a/src/core/include/megbrain/ir/base.td
+++ b/src/core/include/megbrain/ir/base.td
@@ -33,10 +33,11 @@ class MgbHashableAttrMixin {
   string reprFunction = "std::to_string($0)";
 }
 
-class MgbEnumAttrMixin<string namespace, string name, list<string> members> {
+class MgbEnumAttrMixin<string namespace, string name, list<string> members, bit toString> {
   string parentNamespace = namespace;
   string enumName = name;
   list<string> enumMembers = members;
+  bit supportToString = toString;
 }
 
 class MgbAttrWrapper;
@@ -165,8 +166,8 @@ class MgbTupleAttr<list<MgbAttrWrapper> args>:
 }
 
 // -- enum types
-class MgbEnumAttr<string namespace, string enumName, list<string> members>:
-    HashableAttr<namespace # "::" # enumName>, MgbEnumAttrMixin<namespace, enumName, members> {
+class MgbEnumAttr<string namespace, string enumName, list<string> members, bit toString=0>:
+    HashableAttr<namespace # "::" # enumName>, MgbEnumAttrMixin<namespace, enumName, members, toString> {
   let storageType = "::mlir::IntegerAttr";
   let convertFromStorage = "static_cast<" # returnType # ">($_self.getInt())";
   let constBuilderCall = "$_builder.getI32IntegerAttr(static_cast<int32_t>($0))";
@@ -242,7 +243,6 @@ class MgbPackedParamBase<string className, string accessor>:
 class MgbHashableOpMixin {
   string hashFunction = ?;
   string cmpFunction = ?;
-  bit usingModeName = 0;
 }
 
 class MgbOp<string mnemonic, list<MgbParamBase> params=[], list<OpTrait> traits=[]>:
@@ -251,6 +251,7 @@ class MgbOp<string mnemonic, list<MgbParamBase> params=[], list<OpTrait> traits=
   dag extraArguments = (ins);
   // TODO: remove it
   code extraOpdefDecl = ?;
+  code nameFunction = ?;
 
   let arguments = !con(
     !foldl(inputs, params, args, param, !con(args, param.fields)),
diff --git a/src/core/include/megbrain/ir/ops.td b/src/core/include/megbrain/ir/ops.td
index 674acc7e..8dae0591 100644
--- a/src/core/include/megbrain/ir/ops.td
+++ b/src/core/include/megbrain/ir/ops.td
@@ -21,7 +21,9 @@ include "mlir/Interfaces/SideEffectInterfaces.td"
 def Elemwise : MgbHashableOp<"Elemwise", [ElemwiseParam], [NoSideEffect]> {
   let inputs = (ins Variadic<AnyType>:$input);
   let results = (outs AnyType);
-  let usingModeName = 1;
+  let nameFunction = [{
+    return to_string($_self.mode);
+  }];
 }
 
 def Reduce: MgbHashableOp<"Reduce", [ReduceParam]>;
@@ -248,7 +250,9 @@ def ElemwiseMultiType: MgbHashableOp<"ElemwiseMultiType", [ElemwiseMultiTypePara
   let extraArguments = (ins
     MgbDTypeAttr:$dtype
   );
-  let usingModeName = 1;
+  let nameFunction = [{
+    return to_string($_self.mode);
+  }];
 }
 
 def InplaceAdd: MgbHashableOp<"InplaceAdd", [EmptyParam]>;