SPIRAL:: Code generation for DSP transforms

Fast changing, increasingly complex, and diverse computing platforms pose central problems in scientific computing: How to achieve, with reasonable effort, portable optimal performance? We present SPIRAL, which considers this problem for the performance-critical domain of linear digital signal processing (DSP) transforms. For a specified transform, SPIRAL automatically gen-crates high-performance code that is tuned to the given platform. SPIRAL formulates the timing as an optimization problem and exploits the domain-specific mathematical structure of transform algorithins to implement a feedback-driven optimizer Similar to a human expert, for a specified transform, SPIRAL intelligently generates and explores algorithmic and implementation choices to find the best match to the computer's microarchitecture. The intelligence is provided by search and learning techniques that exploit the structure of the algorithm and implementation space to guide the exploration and optimization. SPIRAL generates high-performance code for a broad set of DSP transforms, including the discrete Fourier transform, other trigonometric transforms, filter transforms, and discrete wavelet transforms. Experimental results show that the code generated by SPIRAL competes with, and sometimes outperforms, the best available human timed transform library code.