SPIRAL: A System for Implementation and Platform-Adaptation of Signal Processing Algorithms. Jeremy Johnson Drexel University email: jjohnson@mcs.drexel.edu Markus Pueschel Carnegie Mellon University email: pueschel@ece.cmu.edu Abstract: The SPIRAL system allows the user to obtain high-performance platform-adapted implementations of fast signal transforms from a high-level mathematical formulation. At the simplest level, the user can specify the desired transforms by giving their names and sizes and ask for an implementation on a given platform. A more interactive session would allow the user to guide the implementation process selecting from a database of algorithm rules, implementation strategies, and search methods. A more sophisticated user can define new transforms and symbolic rules for deriving fast algorithms for the transform. Signal transforms can be represented by matrices and fast algorithms for computing the transform are derived by factoring the transform matrix into a product of sparse structured matrices. The SPIRAL system derives algorithm choices from symbolic rules corresponding to such matrix factorizations. Tools are provided for automatically deriving matrix factorizations (formula generator), translating matrix factorizations into efficient programs (SPL language and compiler), verifying the derived factorizations and implementations (verifier), and searching though the space of formulas and implementation strategies for the optimal implementation (search engine). This poster presents an implementation of the SPIRAL system using the GAP computer algebra system. SPIRAL is a joint project funded by DARPA. More information about the SPIRAL system and project can be obtained at http://www.ece.cmu.edu/~spiral.