Compiling for the Molen Programming Paradigm

In this paper we present compiler extensions for the Molen programming paradigm, which is a sequential consistency paradigm for programming custom computing machines (CCM). The compiler supports instruction set extensions and register file extensions. Based on pragma annotations in the application code, it identifies the code fragments implemented on the reconfigurable hardware and automatically maps the application on the target reconfigurable architecture. We also define and implement a mechanism that allows multiple operations to be executed in parallel on the reconfigurable hardware. In a case study, the Molen processor has been evaluated. We considered two popular multimedia benchmarks: mpeg2enc and ijpeg and some well-known timeconsuming operations implemented in the reconfigurable hardware. The total number of executed instructions has been reduced with 72% for mpeg2enc and 35% for ijpeg encoder, compared to their pure software implementations on a general purpose processor (GPP).