fix(dnn): fix the modulo of int

GitOrigin-RevId: 6f7280246b

dnn/src/common/elemwise/kern_defs.cuh

@@ -229,7 +229,7 @@ DEF_KERN(dt_bool, EQ, x == y);
 DEF_KERN_INT(FLOOR_DIV, dispatch_floordiv_int(x, y));
 DEF_KERN_FLOAT(FLOOR_DIV, floorf(x / y));
 
-DEF_KERN_INT(MOD, x % y);
+DEF_KERN_INT(MOD, ((y + x % y) % y));  // consistent with python modulo
 DEF_KERN_FLOAT(MOD, fmodf(x, y));
 
 DEF_KERN_INT(SHL, x << y);

dnn/test/common/elemwise.cpp

@@ -878,8 +878,8 @@ DEF_TEST(all_modes) {
     } while (0)
 
         if (trait.allow_int) {
-            run(dtype::Int8{});
             run(dtype::Int32{});
+            run(dtype::Int8{});
         }
         if (trait.allow_float) {
             DNN_FLOAT16_SELECT(

dnn/test/naive/elemwise_multi_type.cpp

@@ -280,4 +280,24 @@ TEST_F(NAIVE, ELEMWISE_QUANTIZED_MODE_TERNARY) {
     }
 }
 
+TEST_F(NAIVE, ELELMWISE_INT_MODULO) {
+    Checker<Elemwise> checker(handle(), /* check_dispatch */ false);
+    Elemwise::Param param;
+    param.mode = Elemwise::Param::Mode::MOD;
+
+    checker.set_param(param).exect(
+            Testcase{
+                    TensorValue(
+                            {10}, dtype::Int32(),
+                            {10, 24, -6, -20, 10, -90, 45, 3, -1, 0}),
+                    TensorValue(
+                            {10}, dtype::Int32(), {3, 7, 5, -3, -6, 11, 7, -1, 8, -1}),
+                    {}},
+            Testcase{
+                    {},
+                    {},
+                    TensorValue(
+                            {10}, dtype::Int32(), {1, 3, 4, -2, -2, 9, 3, 0, 7, 0})});
+}
+
 // vim: syntax=cpp.doxygen

src/opr/test/basic_arith/elemwise.cpp

@@ -25,7 +25,7 @@ float do_mod(float a, float b) {
 }
 
 int do_mod(int a, int b) {
-    return a % b;
+    return (a % b + b) % b;
 }
 
 float do_floor_div(float a, float b) {