Application-driven design of DSP architectures and compilers

Current DSP architectures are designed to enhance the execution of computationally-intensive, kernel-like loops. Their peculiar architectural features are often difficult for high-level language compilers to exploit. Moreover, their tightly-encoded instruction sets usually restrict the exploitation of instruction-level parallelism beyond a few instances. The quality of compiler-generated code is therefore poor when compared to hand-coded assembly language. In this paper we argue for an application-driven approach to designing flexible DSP architectures and effective compilers. We show that the run-time behavior and architectural characteristics of DSP kernels are different from those of DSP applications. We also show that when given a sufficiently flexible target architecture, a compiler is capable of effectively exploiting instances of instruction-level parallelism and DSP-specific architectural features. Finally, we show that a suitable DSP architecture is one that provides the functionality to support digital signal processing requirements, and the flexibility that enables a compiler to generate efficient code.