Add the step builtin function support
Add the step builtin function support

Signed-off-by: Junyan He <8f73a735c668918c9613b750d3a88ebf2489599f@linux.intel.com>
Reviewed-by: Song, Ruiling <286a174c1339c6eff91abc41c3a1012c95030c95@intel.com>

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