In the process of developping compiler for DSP based on compiler infrastructure Openimpact, the generation of debugging information is necessary for the support of debugging. Openimpact doesn't support the generation of debugging information which is only carried from source code to front end, stored in the form of advanced intermediate language Pcode. To support the generation of debugging information, it is necessary to make the corresponding expansion on Openimpact. It is discussed in detail that the concrete methods for expansion, containing the conversion of debugging information from Pcode to low-level intermediate language format Lcode and from Lcode format to assembly format.