Synergistic Memory Optimisations: Precision Tuning in Heterogeneous Memory Hierarchies

Balancing energy efficiency and high performance in embedded systems requires fine-tuning hardware and software components to co-optimize their interaction. In this work, we address the automated optimization of memory usage through a compiler toolchain that leverages DMA-aware precision tuning and mathematical function memorization. The proposed solution extends the LLVM infrastructure, employing the TAFFO plugins for precision tuning, with the SeTHeT extension for DMA-aware precision tuning and LuTHeT for automated, DMA-aware mathematical function memorization. We performed an experimental assessment on hero, a heterogeneous platform employing RISC-v cores as a parallel accelerator. Our solution enables speedups ranging from 1.5× to 51.1× on AxBench benchmarks that employ trigonometrical functions and 4.23-48.4× on PolyBench benchmarks over the baseline hero platform.