C and C++ are very powerful and expressive programming languages. Even so, these languages lack the power to express certain programming details that can be critical to achieving good compiler performance. The role of a DSP Compiler Tuning Tool (CTT) is to recognize such situations, inform the developer about what is missing, and exactly how to address it. It is as if a compiler expert pores over the code and shows how to improve it specifically for a DSP. This paper explores how performance improvements obtained through use of a DSP CTT can be substantial.