MOVE-Pro: A low power and high code density TTA architecture

Transport Triggered Architectures (TTAs) possess many advantageous, such as modularity, flexibility, and scalability. As an exposed datapath architecture, TTAs can effectively reduce the register file (RF) pressure in both number of accesses and number of RF ports. However, the conventional TTAs also have some evident disadvantages, such as relative low code density, dynamic-power wasting due to separate scheduling of source operands, and inefficient support for variant immediate values. In order to preserve the merit of conventional TTAs, while solving these aforementioned issues, we propose, MOVE-Pro, a novel low power and high code density TTA architecture. With optimizations at instruction set architecture (ISA), architecture, circuit, and compiler levels, the low-power potential of TTAs is fully exploited. Moreover, with a much denser code size, TTAs performance is also improved accordingly. In a head-to-head comparison between a two-issue MOVE-Pro processor and its RISC counterpart, we shown that up to 80% of RF accesses can be reduced, and the reduction in RF power is successfully transferred to the total core power saving. Up to 11% reduction of the total core power is achieved by our MOVE-Pro processor, while the code density is almost the same as its RISC counterpart.