Design space exploration tools for the ByoRISC configurable processor family
In this paper, the ByoRISC (Build your own RISC) configurable application-specific instruction-set processor (ASIP) family is presented. ByoRISCs, as vendor-independent cores, provide extensive architectural parameters over a baseline processor, which can be customized by application-specific hardware extensions (ASHEs). Such extensions realize multi-input multi-output (MIMO) custom instructions with local state and load/store accesses to the data memory. ByoRISCs incorporate a true multi-port register file, zero-overhead custom instruction decoding, and scalable data forwarding mechanisms. Given these design decisions, ByoRISCs provide a unique combination of features that allow their use as architectural testbeds and the seamless and rapid development of new high-performance ASIPs. 
The performance characteristics of ByoRISCs, implemented as vendor-independent cores, have been evaluated for both ASIC and FPGA implementations, and it is proved that they provide a viable solution in FPGA-based system-on-a-chip design. A case study of an image processing pipeline is also presented to highlight the process of utilizing a ByoRISC custom processor. A peak performance speedup of up to 8.5$\times$ can be observed, whereas an average performance speedup of 4.4$\times$ on Xilinx Virtex-4 targets is achieved. In addition, ByoRISC outperforms an experimental VLIW architecture named VEX even in its 16-wide configuration for a number of data-intensive application kernels.