compute shader compile in ES3_1

HI ,guy
I have a compute shader ,and it has compiled success in shader model 5.0 .But when I choose Settings->Preview Rending Levle ->High-End Mobile->Default High-End Mobile. UE4 is crashed and output message :
[2018.06.28-06.44.02:803][624]LogShaderCompilers: Error: Errors compiling global shader FMyComputeShader :
[2018.06.28-06.44.02:803][624]LogShaderCompilers: Error: (): Unrecognized shader frequency
So how can I use compute shader in es3_1 or mobile?