That's just the code in Linux that calls RDRAND.

Here is the actual instruction in VHDL:

  --
  -- copyright NSA, Top Secret//UMBRA
  -- 

  entity RDRAND is
  port(	
    RND: out rnd_long
  );
  end RDRAND;  

  architecture RDRAND of x64_op is
  begin
      
    RND <=  x"4e5341746f524e44"; 

  end RDRAND;