diff --git a/expression/builtin_arithmetic.go b/expression/builtin_arithmetic.go
index f2524dd0792fa..77ae11d93d7de 100644
--- a/expression/builtin_arithmetic.go
+++ b/expression/builtin_arithmetic.go
@@ -670,6 +670,7 @@ func (c *arithmeticIntDivideFunctionClass) getFunction(ctx sessionctx.Context, a
 			bf.tp.Flag |= mysql.UnsignedFlag
 		}
 		sig := &builtinArithmeticIntDivideIntSig{bf}
+		sig.setPbCode(tipb.ScalarFuncSig_IntDivideInt)
 		return sig, nil
 	}
 	bf := newBaseBuiltinFuncWithTp(ctx, args, types.ETInt, types.ETDecimal, types.ETDecimal)
@@ -677,6 +678,7 @@ func (c *arithmeticIntDivideFunctionClass) getFunction(ctx sessionctx.Context, a
 		bf.tp.Flag |= mysql.UnsignedFlag
 	}
 	sig := &builtinArithmeticIntDivideDecimalSig{bf}
+	sig.setPbCode(tipb.ScalarFuncSig_IntDivideDecimal)
 	return sig, nil
 }
 
@@ -834,6 +836,7 @@ func (c *arithmeticModFunctionClass) getFunction(ctx sessionctx.Context, args []
 			bf.tp.Flag |= mysql.UnsignedFlag
 		}
 		sig := &builtinArithmeticModRealSig{bf}
+		sig.setPbCode(tipb.ScalarFuncSig_ModReal)
 		return sig, nil
 	} else if lhsEvalTp == types.ETDecimal || rhsEvalTp == types.ETDecimal {
 		bf := newBaseBuiltinFuncWithTp(ctx, args, types.ETDecimal, types.ETDecimal, types.ETDecimal)
@@ -842,6 +845,7 @@ func (c *arithmeticModFunctionClass) getFunction(ctx sessionctx.Context, args []
 			bf.tp.Flag |= mysql.UnsignedFlag
 		}
 		sig := &builtinArithmeticModDecimalSig{bf}
+		sig.setPbCode(tipb.ScalarFuncSig_ModDecimal)
 		return sig, nil
 	} else {
 		bf := newBaseBuiltinFuncWithTp(ctx, args, types.ETInt, types.ETInt, types.ETInt)
@@ -849,6 +853,7 @@ func (c *arithmeticModFunctionClass) getFunction(ctx sessionctx.Context, args []
 			bf.tp.Flag |= mysql.UnsignedFlag
 		}
 		sig := &builtinArithmeticModIntSig{bf}
+		sig.setPbCode(tipb.ScalarFuncSig_ModInt)
 		return sig, nil
 	}
 }
diff --git a/expression/builtin_arithmetic_test.go b/expression/builtin_arithmetic_test.go
index a1e5afc63180d..dfc8af3d8f364 100644
--- a/expression/builtin_arithmetic_test.go
+++ b/expression/builtin_arithmetic_test.go
@@ -23,6 +23,7 @@ import (
 	"github.com/pingcap/tidb/util/chunk"
 	"github.com/pingcap/tidb/util/testleak"
 	"github.com/pingcap/tidb/util/testutil"
+	"github.com/pingcap/tipb/go-tipb"
 )
 
 func (s *testEvaluatorSuite) TestSetFlenDecimal4RealOrDecimal(c *C) {
@@ -376,6 +377,12 @@ func (s *testEvaluatorSuite) TestArithmeticDivide(c *C) {
 		sig, err := funcs[ast.Div].getFunction(s.ctx, s.datumsToConstants(types.MakeDatums(tc.args...)))
 		c.Assert(err, IsNil)
 		c.Assert(sig, NotNil)
+		switch sig.(type) {
+		case *builtinArithmeticIntDivideIntSig:
+			c.Assert(sig.PbCode(), Equals, tipb.ScalarFuncSig_IntDivideInt)
+		case *builtinArithmeticIntDivideDecimalSig:
+			c.Assert(sig.PbCode(), Equals, tipb.ScalarFuncSig_IntDivideDecimal)
+		}
 		val, err := evalBuiltinFunc(sig, chunk.Row{})
 		c.Assert(err, IsNil)
 		c.Assert(val, testutil.DatumEquals, types.NewDatum(tc.expect))
@@ -601,6 +608,14 @@ func (s *testEvaluatorSuite) TestArithmeticMod(c *C) {
 		c.Assert(err, IsNil)
 		c.Assert(sig, NotNil)
 		val, err := evalBuiltinFunc(sig, chunk.Row{})
+		switch sig.(type) {
+		case *builtinArithmeticModRealSig:
+			c.Assert(sig.PbCode(), Equals, tipb.ScalarFuncSig_ModReal)
+		case *builtinArithmeticModIntSig:
+			c.Assert(sig.PbCode(), Equals, tipb.ScalarFuncSig_ModInt)
+		case *builtinArithmeticModDecimalSig:
+			c.Assert(sig.PbCode(), Equals, tipb.ScalarFuncSig_ModDecimal)
+		}
 		c.Assert(err, IsNil)
 		c.Assert(val, testutil.DatumEquals, types.NewDatum(tc.expect))
 	}