How to change the Tensor-RT input data dims dynamic ???

when using tensor-rt API to create an engine you must know input data dims, now i want to create an model that have one input and it’s dims not unique, what can i do?
for example:
DoInference1 : input : DimsNCHW{1,3,256,256}
DoInference2 : input : DimsNCHW{2,3,256,256}
DoInference3 : input : DimsNCHW{3,3,256,256}


Dynamic input is not supported by current TensorRT.
We are checking the possibility but no concrete schedule to share.