Relax.broadcast_to don't support?

Hi,

While I test with below script, I met error as: TVMError: CodeGenVM cannot handle this intrinsic now: Op(relax.broadcast_to)

I already add LegalizeOps before the build, not sure how to fix it… @Hzfengsy

def get_module(data_shape, bias_shape, dtype):
    with IRBuilder() as builder:
        with relax_builder.function():
            R.func_name("main")
            data = R.arg("data", R.Tensor(data_shape, dtype))
            bias = R.arg("bias", R.Tensor((1, 1, 1, bias_shape), dtype))

            with R.dataflow() as frame:
                bias = R.emit(R.broadcast_to(bias, R.shape_of(data)))
                bias = R.emit(R.reshape(bias, [-1]))
                data = R.emit(R.reshape(data, [-1]))

                output = R.emit(data+bias)
                R.output(output)

            R.func_ret_value(frame.output_vars[0])

    func = builder.get()
    return tvm.IRModule({"main": func})


data_shape = (1, 64, 64, 8)
bias_shape = 8
dtype = "float16"
mod = get_module(data_shape, bias_shape, dtype)
print(mod)
mod = relax.transform.LegalizeOps()(mod)

with tvm.target.Target("cuda"):
    mod = tvm.tir.transform.DefaultGPUSchedule()(mod)
print(mod)

with tvm.transform.PassContext():
    ex = relax.build(mod, "cuda")