This paper presents a new DSP-oriented code optimization method to enhance performance by exploiting the specific architectural features of digital signal processors. In the proposed method, a source code is translated into the static single assignment form while preserving the high-level information related to the address computation of array accesses. The information is used in generating auto-modification addressing operations provided by most digital signal processors. In addition to the conventional control-data flow graph, a new graph is employed to find auto-modification addressing modes efficiently. Experimental results on benchmark programs show that the proposed method is effective in improving performance and reducing code size.