replace pad with pad2d

x2paddle/op_mapper/tf_op_mapper.py

@@ -667,8 +667,14 @@ class TFOpMapper(OpMapper):
         paddings = paddings.value.flatten().tolist()
         if input.tf_data_format == "NHWC" and len(input.out_shapes[0]) == 4:
             paddings = [paddings[i] for i in [0, 1, 6, 7, 2, 3, 4, 5]]
+
+        pad_op = "pad"
+        if len(input.out_shapes[0]) == 4:
+            if paddings[0] + paddings[1] + paddings[2] + paddings[3] == 0:
+                paddings = paddings[4:]
+                pad_op = "pad2d"
         attr = {"paddings": paddings}
-        node.fluid_code.add_layer("pad",
+        node.fluid_code.add_layer(pad_op,
                                   inputs=input,
                                   output=node,
                                   param_attr=attr)