FPGA code accelerators - the compiler perspective

FPGA-based accelerators have repeatedly demonstrated superior speed-ups on an ever-widening spectrum of applications. However, their use remains beyond the reach of traditionally trained applications code developers because of the complexity of their programming tool-chain. Compilers for high-level languages targeting FPGAs have to bridge a huge abstraction gap between two divergent computational models: a temporal, sequentially consistent, control driven execution in the stored program model versus a spatial, parallel, data-flow driven execution in the spatial hardware model. In this paper we discuss these challenges to the compiler designer and report on our experience with the ROCCC toolset.